Merge pull request #124 from docker/feat-generate-vsa-policy-uri

feat: add `digest` and `downloadLocation` to VSA policy
feat: add no policy file error
2024-08-14 16:50:16 -05:00 · 2024-08-14 16:25:41 -05:00 · 2024-08-14 16:13:36 -05:00 · 2024-08-14 16:10:54 -05:00 · 2024-08-14 15:27:02 -05:00 · 2024-08-14 15:01:01 -05:00
65 changed files with 1286 additions and 1002 deletions
--- a/README.md
+++ b/README.md
@@ -345,7 +345,11 @@ The VSA can be signed and published to the registry using the signing functions
    "timeVerified": "2024-04-19T08:00:00.01Z",
    "resourceUri": "pkg:docker/example.org/example-image@1.0?platform=linux%2Famd64&digest=sha256%3A49f717386e5462e945232569a97a05831cb83bef8c3369be3bb7ea1793686960",
    "policy": {
-      "uri": "https://example.org/internal-policy/v1"
+      "uri": "https://example.org/internal-policy/v1",
+      "downloadLocation": "https://docker.github.io/tuf-staging/targets/docker/d71d6b8f49fcba1295b16f5394dd5863a14e4277eb663d66d8c48e392509afe0.policy.rego",
+      "digest": {
+        "sha256": "d71d6b8f49fcba1295b16f5394dd5863a14e4277eb663d66d8c48e392509afe0"
+      }
    },
    "verificationResult": "PASSED",
    "verifiedLevels": ["SLSA_BUILD_LEVEL_3"]
--- a/codecov.yml
+++ b/codecov.yml
@@ -1,2 +1,5 @@
 ignore:
  - "internal/test"
+coverage:
+  status:
+    patch: false
--- a/go.mod
+++ b/go.mod
@@ -13,32 +13,32 @@ require (
 	github.com/google/go-containerregistry v0.20.1
 	github.com/hashicorp/go-cleanhttp v0.5.2
 	github.com/in-toto/in-toto-golang v0.9.0
-	github.com/open-policy-agent/opa v0.67.0
+	github.com/open-policy-agent/opa v0.67.1
 	github.com/opencontainers/image-spec v1.1.0
 	github.com/package-url/packageurl-go v0.1.3
 	github.com/secure-systems-lab/go-securesystemslib v0.8.0
-	github.com/sigstore/cosign/v2 v2.3.0
+	github.com/sigstore/cosign/v2 v2.4.0
 	github.com/sigstore/rekor v1.3.6
-	github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.7
-	github.com/sigstore/sigstore/pkg/signature/kms/gcp v1.8.7
+	github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.8
+	github.com/sigstore/sigstore/pkg/signature/kms/gcp v1.8.8
 	github.com/stretchr/testify v1.9.0
 	github.com/testcontainers/testcontainers-go/modules/registry v0.32.0
 	github.com/theupdateframework/go-tuf/v2 v2.0.0
-	google.golang.org/api v0.189.0
+	google.golang.org/api v0.191.0
 	sigs.k8s.io/yaml v1.4.0
 )

-// fork of a fork (in case it goes away) with changes to support ArtifactType (https://github.com/google/go-containerregistry/pull/1931)
-replace github.com/google/go-containerregistry => github.com/kipz/go-containerregistry v0.0.0-20240722163910-ebe90246535d
+// fork with changes to support ArtifactType (https://github.com/google/go-containerregistry/pull/1931)
+replace github.com/google/go-containerregistry => github.com/docker/go-containerregistry v0.0.0-20240808132857-c8bfc44af7c8

 require (
 	cloud.google.com/go v0.115.0 // indirect
-	cloud.google.com/go/auth v0.7.2 // indirect
+	cloud.google.com/go/auth v0.7.3 // indirect
 	cloud.google.com/go/auth/oauth2adapt v0.2.3 // indirect
 	cloud.google.com/go/compute/metadata v0.5.0 // indirect
-	cloud.google.com/go/iam v1.1.10 // indirect
-	cloud.google.com/go/kms v1.18.2 // indirect
-	cloud.google.com/go/longrunning v0.5.9 // indirect
+	cloud.google.com/go/iam v1.1.12 // indirect
+	cloud.google.com/go/kms v1.18.4 // indirect
+	cloud.google.com/go/longrunning v0.5.11 // indirect
 	dario.cat/mergo v1.0.0 // indirect
 	github.com/Azure/go-ansiterm v0.0.0-20230124172434-306776ec8161 // indirect
 	github.com/Microsoft/go-winio v0.6.2 // indirect
@@ -57,7 +57,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/ecrpublic v1.24.1 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.11.3 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.11.17 // indirect
-	github.com/aws/aws-sdk-go-v2/service/kms v1.35.1 // indirect
+	github.com/aws/aws-sdk-go-v2/service/kms v1.35.3 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sso v1.22.4 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.4 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.30.3 // indirect
@@ -75,7 +75,7 @@ require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/digitorus/pkcs7 v0.0.0-20230818184609-3a137a874352 // indirect
 	github.com/digitorus/timestamp v0.0.0-20231217203849-220c5c2851b7 // indirect
-	github.com/docker/cli v26.1.3+incompatible // indirect
+	github.com/docker/cli v27.1.1+incompatible // indirect
 	github.com/docker/distribution v2.8.3+incompatible // indirect
 	github.com/docker/docker v27.1.0+incompatible // indirect
 	github.com/docker/docker-credential-helpers v0.8.1 // indirect
@@ -101,13 +101,12 @@ require (
 	github.com/gobwas/glob v0.2.3 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
-	github.com/golang/protobuf v1.5.4 // indirect
 	github.com/golang/snappy v0.0.4 // indirect
 	github.com/google/certificate-transparency-go v1.2.1 // indirect
-	github.com/google/s2a-go v0.1.7 // indirect
+	github.com/google/s2a-go v0.1.8 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.2 // indirect
-	github.com/googleapis/gax-go/v2 v2.12.5 // indirect
+	github.com/googleapis/gax-go/v2 v2.13.0 // indirect
 	github.com/gorilla/mux v1.8.1 // indirect
 	github.com/hashicorp/go-retryablehttp v0.7.7 // indirect
 	github.com/hashicorp/hcl v1.0.1-vault-5 // indirect
@@ -149,7 +148,8 @@ require (
 	github.com/shibumi/go-pathspec v1.3.0 // indirect
 	github.com/shirou/gopsutil/v3 v3.24.4 // indirect
 	github.com/shoenig/go-m1cpu v0.1.6 // indirect
-	github.com/sigstore/sigstore v1.8.7 // indirect
+	github.com/sigstore/protobuf-specs v0.3.2 // indirect
+	github.com/sigstore/sigstore v1.8.8 // indirect
 	github.com/sigstore/timestamp-authority v1.2.2 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
@@ -184,17 +184,17 @@ require (
 	go.uber.org/zap v1.27.0 // indirect
 	golang.org/x/crypto v0.25.0 // indirect
 	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842 // indirect
-	golang.org/x/mod v0.17.0 // indirect
+	golang.org/x/mod v0.19.0 // indirect
 	golang.org/x/net v0.27.0 // indirect
-	golang.org/x/oauth2 v0.21.0 // indirect
-	golang.org/x/sync v0.7.0 // indirect
+	golang.org/x/oauth2 v0.22.0 // indirect
+	golang.org/x/sync v0.8.0 // indirect
 	golang.org/x/sys v0.22.0 // indirect
 	golang.org/x/term v0.22.0 // indirect
 	golang.org/x/text v0.16.0 // indirect
-	golang.org/x/time v0.5.0 // indirect
-	google.golang.org/genproto v0.0.0-20240722135656-d784300faade // indirect
-	google.golang.org/genproto/googleapis/api v0.0.0-20240701130421-f6361c86f094 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade // indirect
+	golang.org/x/time v0.6.0 // indirect
+	google.golang.org/genproto v0.0.0-20240730163845-b1a4ccb954bf // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20240725223205-93522f1f2a9f // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240730163845-b1a4ccb954bf // indirect
 	google.golang.org/grpc v1.65.0 // indirect
 	google.golang.org/protobuf v1.34.2 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
--- a/go.sum
+++ b/go.sum
@@ -1,18 +1,18 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 cloud.google.com/go v0.115.0 h1:CnFSK6Xo3lDYRoBKEcAtia6VSC837/ZkJuRduSFnr14=
 cloud.google.com/go v0.115.0/go.mod h1:8jIM5vVgoAEoiVxQ/O4BFTfHqulPZgs/ufEzMcFMdWU=
-cloud.google.com/go/auth v0.7.2 h1:uiha352VrCDMXg+yoBtaD0tUF4Kv9vrtrWPYXwutnDE=
-cloud.google.com/go/auth v0.7.2/go.mod h1:VEc4p5NNxycWQTMQEDQF0bd6aTMb6VgYDXEwiJJQAbs=
+cloud.google.com/go/auth v0.7.3 h1:98Vr+5jMaCZ5NZk6e/uBgf60phTk/XN84r8QEWB9yjY=
+cloud.google.com/go/auth v0.7.3/go.mod h1:HJtWUx1P5eqjy/f6Iq5KeytNpbAcGolPhOgyop2LlzA=
 cloud.google.com/go/auth/oauth2adapt v0.2.3 h1:MlxF+Pd3OmSudg/b1yZ5lJwoXCEaeedAguodky1PcKI=
 cloud.google.com/go/auth/oauth2adapt v0.2.3/go.mod h1:tMQXOfZzFuNuUxOypHlQEXgdfX5cuhwU+ffUuXRJE8I=
 cloud.google.com/go/compute/metadata v0.5.0 h1:Zr0eK8JbFv6+Wi4ilXAR8FJ3wyNdpxHKJNPos6LTZOY=
 cloud.google.com/go/compute/metadata v0.5.0/go.mod h1:aHnloV2TPI38yx4s9+wAZhHykWvVCfu7hQbF+9CWoiY=
-cloud.google.com/go/iam v1.1.10 h1:ZSAr64oEhQSClwBL670MsJAW5/RLiC6kfw3Bqmd5ZDI=
-cloud.google.com/go/iam v1.1.10/go.mod h1:iEgMq62sg8zx446GCaijmA2Miwg5o3UbO+nI47WHJps=
-cloud.google.com/go/kms v1.18.2 h1:EGgD0B9k9tOOkbPhYW1PHo2W0teamAUYMOUIcDRMfPk=
-cloud.google.com/go/kms v1.18.2/go.mod h1:YFz1LYrnGsXARuRePL729oINmN5J/5e7nYijgvfiIeY=
-cloud.google.com/go/longrunning v0.5.9 h1:haH9pAuXdPAMqHvzX0zlWQigXT7B0+CL4/2nXXdBo5k=
-cloud.google.com/go/longrunning v0.5.9/go.mod h1:HD+0l9/OOW0za6UWdKJtXoFAX/BGg/3Wj8p10NeWF7c=
+cloud.google.com/go/iam v1.1.12 h1:JixGLimRrNGcxvJEQ8+clfLxPlbeZA6MuRJ+qJNQ5Xw=
+cloud.google.com/go/iam v1.1.12/go.mod h1:9LDX8J7dN5YRyzVHxwQzrQs9opFFqn0Mxs9nAeB+Hhg=
+cloud.google.com/go/kms v1.18.4 h1:dYN3OCsQ6wJLLtOnI8DGUwQ5shMusXsWCCC+s09ATsk=
+cloud.google.com/go/kms v1.18.4/go.mod h1:SG1bgQ3UWW6/KdPo9uuJnzELXY5YTTMJtDYvajiQ22g=
+cloud.google.com/go/longrunning v0.5.11 h1:Havn1kGjz3whCfoD8dxMLP73Ph5w+ODyZB9RUsDxtGk=
+cloud.google.com/go/longrunning v0.5.11/go.mod h1:rDn7//lmlfWV1Dx6IB4RatCPenTwwmqXuiP0/RgoEO4=
 cuelabs.dev/go/oci/ociregistry v0.0.0-20240404174027-a39bec0462d2 h1:BnG6pr9TTr6CYlrJznYUDj6V7xldD1W+1iXPum0wT/w=
 cuelabs.dev/go/oci/ociregistry v0.0.0-20240404174027-a39bec0462d2/go.mod h1:pK23AUVXuNzzTpfMCA06sxZGeVQ/75FdVtW249de9Uo=
 cuelang.org/go v0.9.2 h1:pfNiry2PdRBr02G/aKm5k2vhzmqbAOoaB4WurmEbWvs=
@@ -29,12 +29,12 @@ github.com/AliyunContainerService/ack-ram-tool/pkg/credentials/alibabacloudsdkgo
 github.com/AliyunContainerService/ack-ram-tool/pkg/credentials/alibabacloudsdkgo/helper v0.2.0/go.mod h1:GgeIE+1be8Ivm7Sh4RgwI42aTtC9qrcj+Y9Y6CjJhJs=
 github.com/Azure/azure-sdk-for-go v68.0.0+incompatible h1:fcYLmCpyNYRnvJbPerq7U0hS+6+I79yEDJBqVNcqUzU=
 github.com/Azure/azure-sdk-for-go v68.0.0+incompatible/go.mod h1:9XXNKU+eRnpl9moKnB4QOLf1HestfXbmab5FXxiDBjc=
-github.com/Azure/azure-sdk-for-go/sdk/azcore v1.12.0 h1:1nGuui+4POelzDwI7RG56yfQJHCnKvwfMoU7VsEp+Zg=
-github.com/Azure/azure-sdk-for-go/sdk/azcore v1.12.0/go.mod h1:99EvauvlcJ1U06amZiksfYz/3aFGyIhWGHVyiZXtBAI=
+github.com/Azure/azure-sdk-for-go/sdk/azcore v1.13.0 h1:GJHeeA2N7xrG3q30L2UXDyuWRzDM900/65j70wcM4Ww=
+github.com/Azure/azure-sdk-for-go/sdk/azcore v1.13.0/go.mod h1:l38EPgmsp71HHLq9j7De57JcKOWPyhrsW1Awm1JS6K0=
 github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.7.0 h1:tfLQ34V6F7tVSwoTf/4lH5sE0o6eCJuNDTmH09nDpbc=
 github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.7.0/go.mod h1:9kIvujWAA58nmPmWB1m23fyWic1kYZMxD9CxaWn4Qpg=
-github.com/Azure/azure-sdk-for-go/sdk/internal v1.9.0 h1:H+U3Gk9zY56G3u872L82bk4thcsy2Gghb9ExT4Zvm1o=
-github.com/Azure/azure-sdk-for-go/sdk/internal v1.9.0/go.mod h1:mgrmMSgaLp9hmax62XQTd0N4aAqSE5E0DulSpVYK7vc=
+github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0 h1:ywEEhmNahHBihViHepv3xPBn1663uRv2t2q/ESv9seY=
+github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0/go.mod h1:iZDifYGJTIgIIkYRNWPENUnqx6bJ2xnSDFI2tjwZNuY=
 github.com/Azure/azure-sdk-for-go/sdk/security/keyvault/azkeys v1.1.0 h1:DRiANoJTiW6obBQe3SqZizkuV1PEgfiiGivmVocDy64=
 github.com/Azure/azure-sdk-for-go/sdk/security/keyvault/azkeys v1.1.0/go.mod h1:qLIye2hwb/ZouqhpSD9Zn3SJipvpEnz1Ywl3VUk9Y0s=
 github.com/Azure/azure-sdk-for-go/sdk/security/keyvault/internal v1.0.0 h1:D3occbWoio4EBLkbkevetNMAVX197GkzbUMtqjGWn80=
@@ -102,8 +102,8 @@ github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0 h1:jfIu9sQUG6Ig
 github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0/go.mod h1:t2tdKJDJF9BV14lnkjHmOQgcvEKgtqs5a1N3LNdJhGE=
 github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2 h1:DklsrG3dyBCFEj5IhUbnKptjxatkF07cF2ak3yi77so=
 github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
-github.com/aws/aws-sdk-go v1.54.19 h1:tyWV+07jagrNiCcGRzRhdtVjQs7Vy41NwsuOcl0IbVI=
-github.com/aws/aws-sdk-go v1.54.19/go.mod h1:eRwEWoyTWFMVYVQzKMNHWP5/RV4xIUGMQfXQHfHkpNU=
+github.com/aws/aws-sdk-go v1.55.5 h1:KKUZBfBoyqy5d3swXyiC7Q76ic40rYcbqH7qjh59kzU=
+github.com/aws/aws-sdk-go v1.55.5/go.mod h1:eRwEWoyTWFMVYVQzKMNHWP5/RV4xIUGMQfXQHfHkpNU=
 github.com/aws/aws-sdk-go-v2 v1.30.3 h1:jUeBtG0Ih+ZIFH0F4UkmL9w3cSpaMv9tYYDbzILP8dY=
 github.com/aws/aws-sdk-go-v2 v1.30.3/go.mod h1:nIQjQVp5sfpQcTc9mPSr1B0PaWK5ByX9MOoDadSN4lc=
 github.com/aws/aws-sdk-go-v2/config v1.27.27 h1:HdqgGt1OAP0HkEDDShEl0oSYa9ZZBSOmKpdpsDMdO90=
@@ -126,8 +126,8 @@ github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.11.3 h1:dT3MqvG
 github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.11.3/go.mod h1:GlAeCkHwugxdHaueRr4nhPuY+WW+gR8UjlcqzPr1SPI=
 github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.11.17 h1:HGErhhrxZlQ044RiM+WdoZxp0p+EGM62y3L6pwA4olE=
 github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.11.17/go.mod h1:RkZEx4l0EHYDJpWppMJ3nD9wZJAa8/0lq9aVC+r2UII=
-github.com/aws/aws-sdk-go-v2/service/kms v1.35.1 h1:0gP2OJJT6HM2BYltZ9x+A87OE8LJL96DXeAAdLv3t1M=
-github.com/aws/aws-sdk-go-v2/service/kms v1.35.1/go.mod h1:hGONorZkQCfR5DW6l2xdy7zC8vfO0r9pJlwyg6gmGeo=
+github.com/aws/aws-sdk-go-v2/service/kms v1.35.3 h1:UPTdlTOwWUX49fVi7cymEN6hDqCwe3LNv1vi7TXUutk=
+github.com/aws/aws-sdk-go-v2/service/kms v1.35.3/go.mod h1:gjDP16zn+WWalyaUqwCCioQ8gU8lzttCCc9jYsiQI/8=
 github.com/aws/aws-sdk-go-v2/service/sso v1.22.4 h1:BXx0ZIxvrJdSgSvKTZ+yRBeSqqgPM89VPlulEcl37tM=
 github.com/aws/aws-sdk-go-v2/service/sso v1.22.4/go.mod h1:ooyCOXjvJEsUw7x+ZDHeISPMhtwI3ZCB7ggFMcFfWLU=
 github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.4 h1:yiwVzJW2ZxZTurVbYWA7QOrAaCYQR72t0wrSBfoesUE=
@@ -142,8 +142,8 @@ github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
 github.com/blang/semver v3.5.1+incompatible h1:cQNTCjp13qL8KC3Nbxr/y2Bqb63oX6wdnnjpJbkM4JQ=
 github.com/blang/semver v3.5.1+incompatible/go.mod h1:kRBLl5iJ+tD4TcOOxsy/0fnwebNt5EWlYSAyrTnjyyk=
-github.com/buildkite/agent/v3 v3.75.1 h1:FJg1gss9nUESExTsfx6yWqs/g20Vyd4pHSEB9iuT4pI=
-github.com/buildkite/agent/v3 v3.75.1/go.mod h1:UXCAEaqJnw5UsoZjJ9NxMvdSGc4oMHBnQFQqzGPDM0Y=
+github.com/buildkite/agent/v3 v3.76.2 h1:SweFq3e0N20RikWsVeOXzTjfr0AoOskxm9c0bcNyI0E=
+github.com/buildkite/agent/v3 v3.76.2/go.mod h1:9ffbmJD7d7C/nOcElj6Qm+uIj1QoYh3NNvka4rkKkss=
 github.com/buildkite/go-pipeline v0.10.0 h1:EDffu+LfMY2k5u+iEdo6Jn3obGKsrL5wicc1O/yFeRs=
 github.com/buildkite/go-pipeline v0.10.0/go.mod h1:eMH1kiav5VeiTiu0Mk2/M7nZhKyFeL4iGj7Y7rj4f3w=
 github.com/buildkite/interpolate v0.1.3 h1:OFEhqji1rNTRg0u9DsSodg63sjJQEb1uWbENq9fUOBM=
@@ -218,8 +218,8 @@ github.com/dimchansky/utfbom v1.1.1 h1:vV6w1AhK4VMnhBno/TPVCoK9U/LP0PkLCS9tbxHdi
 github.com/dimchansky/utfbom v1.1.1/go.mod h1:SxdoEBH5qIqFocHMyGOXVAybYJdr71b1Q/j0mACtrfE=
 github.com/distribution/reference v0.6.0 h1:0IXCQ5g4/QMHHkarYzh5l+u8T3t73zM5QvfrDyIgxBk=
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-github.com/docker/cli v26.1.3+incompatible h1:bUpXT/N0kDE3VUHI2r5VMsYQgi38kYuoC0oL9yt3lqc=
-github.com/docker/cli v26.1.3+incompatible/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
+github.com/docker/cli v27.1.1+incompatible h1:goaZxOqs4QKxznZjjBWKONQci/MywhtRv2oNn0GkeZE=
+github.com/docker/cli v27.1.1+incompatible/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
 github.com/docker/distribution v2.8.3+incompatible h1:AtKxIZ36LoNK51+Z6RpzLpddBirtxJnzDrHLEKxTAYk=
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 github.com/docker/docker v27.1.0+incompatible h1:rEHVQc4GZ0MIQKifQPHSFGV/dVgaZafgRf8fCPtDYBs=
@@ -228,6 +228,8 @@ github.com/docker/docker-credential-helpers v0.8.1 h1:j/eKUktUltBtMzKqmfLB0PAgqY
 github.com/docker/docker-credential-helpers v0.8.1/go.mod h1:P3ci7E3lwkZg6XiHdRKft1KckHiO9a2rNtyFbZ/ry9M=
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+github.com/docker/go-containerregistry v0.0.0-20240808132857-c8bfc44af7c8 h1:T/wutVfQ1Oj4H5tbP5IZL5l6PZqzvapVJ5cB4Wy4Ucc=
+github.com/docker/go-containerregistry v0.0.0-20240808132857-c8bfc44af7c8/go.mod h1:z38EKdKh4h7IP2gSfUUqEvalZBqs6AoLeWfUy34nQC8=
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@@ -353,8 +355,8 @@ github.com/google/go-querystring v1.1.0/go.mod h1:Kcdr2DB4koayq7X8pmAG4sNG59So17
 github.com/google/gofuzz v1.2.0 h1:xRy4A+RhZaiKjJ1bPfwQ8sedCA+YS2YcCHW6ec7JMi0=
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-github.com/google/s2a-go v0.1.7 h1:60BLSyTrOV4/haCDW4zb1guZItoSq8foHCXrAnjBo/o=
-github.com/google/s2a-go v0.1.7/go.mod h1:50CgR4k1jNlWBu4UfS4AcfhVe1r6pdZPygJ3R8F0Qdw=
+github.com/google/s2a-go v0.1.8 h1:zZDs9gcbt9ZPLV0ndSyQk6Kacx2g/X+SKYovpnz3SMM=
+github.com/google/s2a-go v0.1.8/go.mod h1:6iNWHTpQ+nfNRN5E00MSdfDwVesa8hhS32PhPO8deJA=
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 github.com/google/trillian v1.6.0 h1:jMBeDBIkINFvS2n6oV5maDqfRlxREAc6CW9QYWQ0qT4=
@@ -364,8 +366,8 @@ github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/enterprise-certificate-proxy v0.3.2 h1:Vie5ybvEvT75RniqhfFxPRy3Bf7vr3h0cechB90XaQs=
 github.com/googleapis/enterprise-certificate-proxy v0.3.2/go.mod h1:VLSiSSBs/ksPL8kq3OBOQ6WRI2QnaFynd1DCjZ62+V0=
-github.com/googleapis/gax-go/v2 v2.12.5 h1:8gw9KZK8TiVKB6q3zHY3SBzLnrGp6HQjyfYBYGmXdxA=
-github.com/googleapis/gax-go/v2 v2.12.5/go.mod h1:BUDKcWo+RaKq5SC9vVYL0wLADa3VcfswbOMMRmB9H3E=
+github.com/googleapis/gax-go/v2 v2.13.0 h1:yitjD5f7jQHhyDsnhKEBU52NdvvdSeGzlAnDPT0hH1s=
+github.com/googleapis/gax-go/v2 v2.13.0/go.mod h1:Z/fvTZXF8/uw7Xu5GuslPw+bplx6SS338j1Is2S+B7A=
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@@ -417,8 +419,6 @@ github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8Hm
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
-github.com/kipz/go-containerregistry v0.0.0-20240722163910-ebe90246535d h1:5QaWAwKhslfqxEyMZY0ofvsbMJkMLcx5E30JFufMVj8=
-github.com/kipz/go-containerregistry v0.0.0-20240722163910-ebe90246535d/go.mod h1:YCMFNQeeXeLF+dnhhWkqDItx/JSkH01j1Kis4PsjzFI=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.17.8 h1:YcnTYrq7MikUT7k0Yb5eceMmALQPYBW/Xltxn0NAMnU=
@@ -493,8 +493,8 @@ github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1y
 github.com/onsi/gomega v1.17.0/go.mod h1:HnhC7FXeEQY45zxNK3PPoIUhzk/80Xly9PcubAlGdZY=
 github.com/onsi/gomega v1.19.0 h1:4ieX6qQjPP/BfC3mpsAtIGGlxTWPeA3Inl/7DtXw1tw=
 github.com/onsi/gomega v1.19.0/go.mod h1:LY+I3pBVzYsTBU1AnDwOSxaYi9WoWiqgwooUqq9yPro=
-github.com/open-policy-agent/opa v0.67.0 h1:FOdsO9yNhfmrh+72oVK7ImWmzruG+VSpfbr5IBqEWVs=
-github.com/open-policy-agent/opa v0.67.0/go.mod h1:aqKlHc8E2VAAylYE9x09zJYr/fYzGX+JKne89UGqFzk=
+github.com/open-policy-agent/opa v0.67.1 h1:rzy26J6g1X+CKknAcx0Vfbt41KqjuSzx4E0A8DAZf3E=
+github.com/open-policy-agent/opa v0.67.1/go.mod h1:aqKlHc8E2VAAylYE9x09zJYr/fYzGX+JKne89UGqFzk=
 github.com/opencontainers/go-digest v1.0.0 h1:apOUWs51W5PlhuyGyz9FCeeBIOUDA/6nW8Oi/yOhh5U=
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 github.com/opencontainers/image-spec v1.1.0 h1:8SG7/vwALn54lVB/0yZ/MMwhFrPYtpEHQb2IpWsCzug=
@@ -555,22 +555,26 @@ github.com/shoenig/go-m1cpu v0.1.6 h1:nxdKQNcEB6vzgA2E2bvzKIYRuNj7XNJ4S/aRSwKzFt
 github.com/shoenig/go-m1cpu v0.1.6/go.mod h1:1JJMcUBvfNwpq05QDQVAnx3gUHr9IYF7GNg9SUEw2VQ=
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 github.com/shoenig/test v0.6.4/go.mod h1:byHiCGXqrVaflBLAMq/srcZIHynQPQgeyvkvXnjqq0k=
-github.com/sigstore/cosign/v2 v2.3.0 h1:rBLVdKMYuER0blmaKMfMNkvawBdK1lTMz2L5PtTPrI8=
-github.com/sigstore/cosign/v2 v2.3.0/go.mod h1:tjACBZS6LoH3bap5hU8MxyGC4DIJiatqhZxuJWFcIJ0=
+github.com/sigstore/cosign/v2 v2.4.0 h1:2NdidNgClg+oXr/fDIr37E/BE6j00gqgUhSiBK2kjSQ=
+github.com/sigstore/cosign/v2 v2.4.0/go.mod h1:j+fH1DCUkcn92qp6ezDj4JbGMri6eG1nLJC+hs64rvc=
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-github.com/sigstore/sigstore v1.8.7 h1:L7/zKauHTg0d0Hukx7qlR4nifh6T6O6UIt9JBwAmTIg=
-github.com/sigstore/sigstore v1.8.7/go.mod h1:MPiQ/NIV034Fc3Kk2IX9/XmBQdK60wfmpvgK9Z1UjRA=
-github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.7 h1:SoahswHQm2JhO8h3KTAeX8IZeE7mSR2Lc53ay5choes=
-github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.7/go.mod h1:TOVOPOqldrrz4dP7x4/0DFQTs9QSXZUoHu21+JHmixA=
-github.com/sigstore/sigstore/pkg/signature/kms/azure v1.8.7 h1:jcdKxc5bvwfL7+ZbeCszaN/qsBd6180fGAHxeX5Ckm0=
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@@ -676,8 +680,8 @@ go.opentelemetry.io/otel/trace v1.28.0 h1:GhQ9cUuQGmNDd5BTCP2dAvv75RdMxEfTmYejp+
 go.opentelemetry.io/otel/trace v1.28.0/go.mod h1:jPyXzNPg6da9+38HEwElrQiHlVMTnVfM3/yv2OlIHaI=
 go.opentelemetry.io/proto/otlp v1.3.1 h1:TrMUixzpM0yuc/znrFTP9MMRh8trP93mkCiDVeXrui0=
 go.opentelemetry.io/proto/otlp v1.3.1/go.mod h1:0X1WI4de4ZsLrrJNLAQbFeLCm3T7yBkR0XqQ7niQU+8=
-go.step.sm/crypto v0.50.0 h1:BqI9sEgocoHDLLHiZnFqdqXl5FjdMvOWKMm/fKL/lrw=
-go.step.sm/crypto v0.50.0/go.mod h1:NCFMhLS6FJXQ9sD9PP282oHtsBWLrI6wXZY0eOkq7t8=
+go.step.sm/crypto v0.51.1 h1:ktUg/2hetEMiBAqgz502ktZDGoDoGrcHFg3XpkmkvvA=
+go.step.sm/crypto v0.51.1/go.mod h1:PdrhttNU/tG9/YsVd4fdlysBN+UV503p0o2irFZQlAw=
 go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
 go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
 go.uber.org/multierr v1.11.0 h1:blXXJkSxSSfBVBlC76pxqeO+LN3aDfLQo+309xJstO0=
@@ -702,8 +706,8 @@ golang.org/x/mod v0.2.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
-golang.org/x/mod v0.17.0 h1:zY54UmvipHiNd+pm+m0x9KhZ9hl1/7QNMyxXbc6ICqA=
-golang.org/x/mod v0.17.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
+golang.org/x/mod v0.19.0 h1:fEdghXQSo20giMthA7cd28ZC+jts4amQ3YMXiP5oMQ8=
+golang.org/x/mod v0.19.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180906233101-161cd47e91fd/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
@@ -726,8 +730,8 @@ golang.org/x/net v0.8.0/go.mod h1:QVkue5JL9kW//ek3r6jTKnTFis1tRmNAW2P1shuFdJc=
 golang.org/x/net v0.27.0 h1:5K3Njcw06/l2y9vpGCSdcxWOYHOUk3dVNGDXN+FvAys=
 golang.org/x/net v0.27.0/go.mod h1:dDi0PyhWNoiUOrAS8uXv/vnScO4wnHQO4mj9fn/RytE=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
-golang.org/x/oauth2 v0.21.0 h1:tsimM75w1tF/uws5rbeHzIWxEqElMehnc+iW793zsZs=
-golang.org/x/oauth2 v0.21.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
+golang.org/x/oauth2 v0.22.0 h1:BzDx2FehcG7jJwgWLELCdmLuxk2i+x9UDpSiss2u0ZA=
+golang.org/x/oauth2 v0.22.0/go.mod h1:XYTD2NtWslqkgxebSiOHnXEap4TF09sJSc7H1sXbhtI=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
@@ -735,8 +739,8 @@ golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.7.0 h1:YsImfSBoP9QPYL0xyKJPq0gcaJdG3rInoqxTWbfQu9M=
-golang.org/x/sync v0.7.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
+golang.org/x/sync v0.8.0 h1:3NFvSEYkUoMifnESzZl15y791HH1qU2xm6eCJU5ZPXQ=
+golang.org/x/sync v0.8.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -785,8 +789,8 @@ golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/text v0.8.0/go.mod h1:e1OnstbJyHTd6l/uOt8jFFHp6TRDWZR/bV3emEE/zU8=
 golang.org/x/text v0.16.0 h1:a94ExnEXNtEwYLGJSIUxnWoxoRz/ZcCsV63ROupILh4=
 golang.org/x/text v0.16.0/go.mod h1:GhwF1Be+LQoKShO3cGOHzqOgRrGaYc9AvblQOmPVHnI=
-golang.org/x/time v0.5.0 h1:o7cqy6amK/52YcAKIPlM3a+Fpj35zvRj2TP+e1xFSfk=
-golang.org/x/time v0.5.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
+golang.org/x/time v0.6.0 h1:eTDhh4ZXt5Qf0augr54TN6suAUudPcawVZeIAPU7D4U=
+golang.org/x/time v0.6.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
@@ -798,26 +802,26 @@ golang.org/x/tools v0.0.0-20201224043029-2b0845dc783e/go.mod h1:emZCQorbCU4vsT4f
 golang.org/x/tools v0.0.0-20210106214847-113979e3529a/go.mod h1:emZCQorbCU4vsT4fOWvOPXz4eW1wZW4PmDk9uLelYpA=
 golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
 golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
-golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d h1:vU5i/LfpvrRCpgM/VPfJLg5KjxD3E+hfT1SH+d9zLwg=
-golang.org/x/tools v0.21.1-0.20240508182429-e35e4ccd0d2d/go.mod h1:aiJjzUbINMkxbQROHiO6hDPo2LHcIPhhQsa9DLh0yGk=
+golang.org/x/tools v0.23.0 h1:SGsXPZ+2l4JsgaCKkx+FQ9YZ5XEtA1GZYuoDjenLjvg=
+golang.org/x/tools v0.23.0/go.mod h1:pnu6ufv6vQkll6szChhK3C3L/ruaIv5eBeztNG8wtsI=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20220517211312-f3a8303e98df/go.mod h1:K8+ghG5WaK9qNqU5K3HdILfMLy1f3aNYFI/wnl100a8=
-google.golang.org/api v0.189.0 h1:equMo30LypAkdkLMBqfeIqtyAnlyig1JSZArl4XPwdI=
-google.golang.org/api v0.189.0/go.mod h1:FLWGJKb0hb+pU2j+rJqwbnsF+ym+fQs73rbJ+KAUgy8=
+google.golang.org/api v0.191.0 h1:cJcF09Z+4HAB2t5qTQM1ZtfL/PemsLFkcFG67qq2afk=
+google.golang.org/api v0.191.0/go.mod h1:tD5dsFGxFza0hnQveGfVk9QQYKcfp+VzgRqyXFxE0+E=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98Agz4BDEuKkezgsaosCRResVns1a3J2ZsMNc=
 google.golang.org/genproto v0.0.0-20200526211855-cb27e3aa2013/go.mod h1:NbSheEEYHJ7i3ixzK3sjbqSGDJWnxyFXZblF3eUsNvo=
-google.golang.org/genproto v0.0.0-20240722135656-d784300faade h1:lKFsS7wpngDgSCeFn7MoLy+wBDQZ1UQIJD4UNM1Qvkg=
-google.golang.org/genproto v0.0.0-20240722135656-d784300faade/go.mod h1:FfBgJBJg9GcpPvKIuHSZ/aE1g2ecGL74upMzGZjiGEY=
-google.golang.org/genproto/googleapis/api v0.0.0-20240701130421-f6361c86f094 h1:0+ozOGcrp+Y8Aq8TLNN2Aliibms5LEzsq99ZZmAGYm0=
-google.golang.org/genproto/googleapis/api v0.0.0-20240701130421-f6361c86f094/go.mod h1:fJ/e3If/Q67Mj99hin0hMhiNyCRmt6BQ2aWIJshUSJw=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade h1:oCRSWfwGXQsqlVdErcyTt4A93Y8fo0/9D4b1gnI++qo=
-google.golang.org/genproto/googleapis/rpc v0.0.0-20240722135656-d784300faade/go.mod h1:Ue6ibwXGpU+dqIcODieyLOcgj7z8+IcskoNIgZxtrFY=
+google.golang.org/genproto v0.0.0-20240730163845-b1a4ccb954bf h1:OqdXDEakZCVtDiZTjcxfwbHPCT11ycCEsTKesBVKvyY=
+google.golang.org/genproto v0.0.0-20240730163845-b1a4ccb954bf/go.mod h1:mCr1K1c8kX+1iSBREvU3Juo11CB+QOEWxbRS01wWl5M=
+google.golang.org/genproto/googleapis/api v0.0.0-20240725223205-93522f1f2a9f h1:b1Ln/PG8orm0SsBbHZWke8dDp2lrCD4jSmfglFpTZbk=
+google.golang.org/genproto/googleapis/api v0.0.0-20240725223205-93522f1f2a9f/go.mod h1:AHT0dDg3SoMOgZGnZk29b5xTbPHMoEC8qthmBLJCpys=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240730163845-b1a4ccb954bf h1:liao9UHurZLtiEwBgT9LMOnKYsHze6eA6w1KQCMVN2Q=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20240730163845-b1a4ccb954bf/go.mod h1:Ue6ibwXGpU+dqIcODieyLOcgj7z8+IcskoNIgZxtrFY=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.23.0/go.mod h1:Y5yQAOtifL1yxbo5wqy6BxZv8vAUGQwXBOALyacEbxg=
 google.golang.org/grpc v1.25.1/go.mod h1:c3i+UQWmh7LiEpx4sFZnkU36qjEYZ0imhYfXVyQciAY=
@@ -875,8 +879,8 @@ k8s.io/utils v0.0.0-20240502163921-fe8a2dddb1d0 h1:jgGTlFYnhF1PM1Ax/lAlxUPE+KfCI
 k8s.io/utils v0.0.0-20240502163921-fe8a2dddb1d0/go.mod h1:OLgZIPagt7ERELqWJFomSt595RzquPNLL48iOWgYOg0=
 sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd h1:EDPBXCAspyGV4jQlpZSudPeMmr1bNJefnuqLsRAsHZo=
 sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd/go.mod h1:B8JuhiUyNFVKdsE8h686QcCxMaH6HrOAZj4vswFpcB0=
-sigs.k8s.io/release-utils v0.8.3 h1:KtOtA4qDmzJyeQ2zkDsFVI25+NViwms/o5eL2NftFdA=
-sigs.k8s.io/release-utils v0.8.3/go.mod h1:fp82Fma06OXBhEJ+GUJKqvcplDBomruK1R/1fWJnsrQ=
+sigs.k8s.io/release-utils v0.8.4 h1:4QVr3UgbyY/d9p74LBhg0njSVQofUsAZqYOzVZBhdBw=
+sigs.k8s.io/release-utils v0.8.4/go.mod h1:m1bHfscTemQp+z+pLCZnkXih9n0+WukIUU70n6nFnU0=
 sigs.k8s.io/structured-merge-diff/v4 v4.3.0 h1:UZbZAZfX0wV2zr7YZorDz6GXROfDFj6LvqCRm4VUVKk=
 sigs.k8s.io/structured-merge-diff/v4 v4.3.0/go.mod h1:N8hJocpFajUSSeSJ9bOZ77VzejKZaXsTtZo4/u7Io08=
 sigs.k8s.io/yaml v1.4.0 h1:Mk1wCc2gy/F0THH0TAp1QYyJNzRm2KCLy3o5ASXVI5E=
--- a/internal/test/test.go
+++ b/internal/test/test.go
@@ -2,21 +2,13 @@ package test

 import (
 	"context"
-	"encoding/base64"
-	"encoding/json"
-	"fmt"
 	"os"
-	"strings"
+	"path/filepath"
 	"testing"

-	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/policy"
 	"github.com/docker/attest/pkg/signerverifier"
 	"github.com/docker/attest/pkg/tlog"
-	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/google/go-containerregistry/pkg/v1/layout"
-	"github.com/google/go-containerregistry/pkg/v1/partial"
-	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	"github.com/secure-systems-lab/go-securesystemslib/dsse"
 )

@@ -29,6 +21,8 @@ const (
 	AWSKMSKeyARN = "arn:aws:kms:us-east-1:175142243308:alias/doi-signing" // sandbox
 )

+var UnsignedTestImage = filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
+
 func CreateTempDir(t *testing.T, dir, pattern string) string {
 	// Create a temporary directory for output oci layout
 	tempDir, err := os.MkdirTemp(dir, pattern)
@@ -45,6 +39,14 @@ func CreateTempDir(t *testing.T, dir, pattern string) string {
 	return tempDir
 }

+func GetMockSigner(_ context.Context) (dsse.SignerVerifier, error) {
+	priv, err := os.ReadFile(filepath.Join("..", "..", "test", "testdata", "test-signing-key.pem"))
+	if err != nil {
+		return nil, err
+	}
+	return signerverifier.LoadKeyPair(priv)
+}
+
 func Setup(t *testing.T) (context.Context, dsse.SignerVerifier) {
 	var tl tlog.TL
 	if UseMockTL {
@@ -80,108 +82,3 @@ func Setup(t *testing.T) (context.Context, dsse.SignerVerifier) {

 	return ctx, signer
 }
-
-type AnnotatedStatement struct {
-	OCIDescriptor   *v1.Descriptor
-	InTotoStatement *intoto.Statement
-	Annotations     map[string]string
-}
-
-func ExtractStatementsFromIndex(idx v1.ImageIndex, mediaType string) ([]*AnnotatedStatement, error) {
-	mfs2, err := idx.IndexManifest()
-	if err != nil {
-		return nil, fmt.Errorf("failed to extract IndexManifest from ImageIndex: %w", err)
-	}
-
-	var statements []*AnnotatedStatement
-
-	for i := range mfs2.Manifests {
-		mf := &mfs2.Manifests[i]
-		if mf.Annotations[attestation.DockerReferenceType] != "attestation-manifest" {
-			continue
-		}
-
-		attestationImage, err := idx.Image(mf.Digest)
-		if err != nil {
-			return nil, fmt.Errorf("failed to extract attestation image with digest %s: %w", mf.Digest.String(), err)
-		}
-		layers, err := attestationImage.Layers()
-		if err != nil {
-			return nil, fmt.Errorf("failed to extract layers from attestation image: %w", err)
-		}
-
-		for _, layer := range layers {
-			// parse layer blob as json
-			mt, err := layer.MediaType()
-			if err != nil {
-				return nil, fmt.Errorf("failed to get layer media type: %w", err)
-			}
-
-			if string(mt) != mediaType {
-				continue
-			}
-			r, err := layer.Uncompressed()
-			if err != nil {
-				return nil, fmt.Errorf("failed to get layer contents: %w", err)
-			}
-			defer r.Close()
-			inTotoStatement := new(intoto.Statement)
-			var desc *v1.Descriptor
-			if strings.HasSuffix(string(mt), "+dsse") {
-				env := new(attestation.Envelope)
-				err = json.NewDecoder(r).Decode(env)
-				if err != nil {
-					return nil, fmt.Errorf("failed to decode env: %w", err)
-				}
-				payload, err := base64.StdEncoding.Strict().DecodeString(env.Payload)
-				if err != nil {
-					return nil, fmt.Errorf("failed to decode payload: %w", err)
-				}
-				err = json.Unmarshal([]byte(payload), inTotoStatement)
-				if err != nil {
-					return nil, fmt.Errorf("failed to decode %s statement: %w", mediaType, err)
-				}
-			} else {
-				desc := new(v1.Descriptor)
-				err = json.NewDecoder(r).Decode(desc)
-				if err != nil {
-					return nil, fmt.Errorf("failed to decode statement: %w", err)
-				}
-			}
-
-			layerDesc, err := partial.Descriptor(layer)
-			if err != nil {
-				return nil, fmt.Errorf("failed to get descriptor for layer: %w", err)
-			}
-			annotations := make(map[string]string)
-			for k, v := range layerDesc.Annotations {
-				annotations[k] = v
-			}
-			statements = append(statements, &AnnotatedStatement{
-				OCIDescriptor:   desc,
-				InTotoStatement: inTotoStatement,
-				Annotations:     annotations,
-			})
-		}
-	}
-	return statements, nil
-}
-
-func ExtractAnnotatedStatements(path string, mediaType string) ([]*AnnotatedStatement, error) {
-	idx, err := layout.ImageIndexFromPath(path)
-	if err != nil {
-		return nil, fmt.Errorf("failed to load image index: %w", err)
-	}
-
-	idxm, err := idx.IndexManifest()
-	if err != nil {
-		return nil, fmt.Errorf("failed to get digest: %w", err)
-	}
-	idxDigest := idxm.Manifests[0].Digest
-
-	mfs, err := idx.ImageIndex(idxDigest)
-	if err != nil {
-		return nil, fmt.Errorf("failed to extract ImageIndex for digest %s: %w", idxDigest.String(), err)
-	}
-	return ExtractStatementsFromIndex(mfs, mediaType)
-}
--- a/pkg/attest/README.md
+++ b/pkg/attest/README.md
@@ -0,0 +1,2 @@
+## attest
+This package implements the top-level signing and verification methods.
--- a/pkg/attest/example_sign_test.go
+++ b/pkg/attest/example_sign_test.go
@@ -5,7 +5,6 @@ import (

 	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/mirror"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/signerverifier"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
@@ -55,7 +54,7 @@ func ExampleSignStatements_remote() {
 	}

 	// push image index with signed attestation-manifests
-	err = mirror.PushIndexToRegistry(signedIndex, ref)
+	err = oci.PushIndexToRegistry(signedIndex, ref)
 	if err != nil {
 		panic(err)
 	}
@@ -70,7 +69,7 @@ func ExampleSignStatements_remote() {
 			},
 		},
 	})
-	err = mirror.SaveIndexAsOCILayout(idx, path)
+	err = oci.SaveIndexAsOCILayout(idx, path)
 	if err != nil {
 		panic(err)
 	}
--- a/pkg/attest/sign.go
+++ b/pkg/attest/sign.go
@@ -12,14 +12,14 @@ import (
 // this is only relevant if there are (unsigned) in-toto statements.
 func SignStatements(ctx context.Context, idx v1.ImageIndex, signer dsse.SignerVerifier, opts *attestation.SigningOptions) ([]*attestation.Manifest, error) {
 	// extract attestation manifests from index
-	attestationManifests, err := attestation.GetAttestationManifestsFromIndex(idx)
+	attestationManifests, err := attestation.ManifestsFromIndex(idx)
 	if err != nil {
 		return nil, fmt.Errorf("failed to load attestation manifests from index: %w", err)
 	}
 	// sign every attestation layer in each manifest
 	for _, manifest := range attestationManifests {
 		for _, layer := range manifest.OriginalLayers {
-			err = manifest.AddAttestation(ctx, signer, layer.Statement, opts)
+			err = manifest.Add(ctx, signer, layer.Statement, opts)
 			if err != nil {
 				return nil, fmt.Errorf("failed to sign attestation layer %w", err)
 			}
--- a/pkg/attest/sign_test.go
+++ b/pkg/attest/sign_test.go
@@ -1,25 +1,13 @@
 package attest

 import (
-	"encoding/json"
-	"fmt"
-	"net/http/httptest"
-	"net/url"
 	"path/filepath"
 	"testing"

 	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/mirror"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
-	"github.com/google/go-containerregistry/pkg/registry"
-	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/google/go-containerregistry/pkg/v1/empty"
-	"github.com/google/go-containerregistry/pkg/v1/layout"
-	"github.com/google/go-containerregistry/pkg/v1/mutate"
-	"github.com/google/go-containerregistry/pkg/v1/static"
-	"github.com/google/go-containerregistry/pkg/v1/types"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	v02 "github.com/in-toto/in-toto-golang/in_toto/slsa_provenance/v0.2"
 	"github.com/stretchr/testify/assert"
@@ -27,7 +15,6 @@ import (
 )

 var (
-	UnsignedTestImage   = filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
 	NoProvenanceImage   = filepath.Join("..", "..", "test", "testdata", "no-provenance-image")
 	PassPolicyDir       = filepath.Join("..", "..", "test", "testdata", "local-policy-pass")
 	PassMirrorPolicyDir = filepath.Join("..", "..", "test", "testdata", "local-policy-mirror")
@@ -46,8 +33,8 @@ func TestSignVerifyOCILayout(t *testing.T) {
 		expectedAttestations int
 		replace              bool
 	}{
-		{"signed replaced", UnsignedTestImage, 0, 4, true},
-		{"without replace", UnsignedTestImage, 4, 4, false},
+		{"signed replaced", test.UnsignedTestImage, 0, 4, true},
+		{"without replace", test.UnsignedTestImage, 4, 4, false},
 		// image without provenance doesn't fail
 		{"no provenance (replace)", NoProvenanceImage, 0, 2, true},
 		{"no provenance (no replace)", NoProvenanceImage, 2, 2, false},
@@ -66,28 +53,18 @@ func TestSignVerifyOCILayout(t *testing.T) {
 			signedIndex := attIdx.Index
 			signedIndex, err = attestation.UpdateIndexImages(signedIndex, signedManifests, attestation.WithReplacedLayers(tc.replace))
 			require.NoError(t, err)
-			// output signed attestations
-			idx := v1.ImageIndex(empty.Index)
-			idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
-				Add: signedIndex,
-				Descriptor: v1.Descriptor{
-					Annotations: map[string]string{
-						oci.OCIReferenceTarget: attIdx.Name,
-					},
-				},
-			})
-			_, err = layout.Write(outputLayout, idx)
+			spec, err := oci.ParseImageSpec(oci.LocalPrefix + outputLayout)
 			require.NoError(t, err)
-			src, err := oci.ParseImageSpec("oci://" + outputLayout)
+			err = oci.SaveIndex([]*oci.ImageSpec{spec}, signedIndex, attIdx.Name)
 			require.NoError(t, err)
-			policy, err := Verify(ctx, src, policyOpts)
+			policy, err := Verify(ctx, spec, policyOpts)
 			require.NoError(t, err)
 			assert.Equalf(t, OutcomeSuccess, policy.Outcome, "Policy should have been found")

-			var allEnvelopes []*test.AnnotatedStatement
+			var allEnvelopes []*attestation.AnnotatedStatement
 			for _, predicate := range []string{intoto.PredicateSPDX, v02.PredicateSLSAProvenance, attestation.VSAPredicateType} {
 				mt, _ := attestation.DSSEMediaType(predicate)
-				statements, err := test.ExtractAnnotatedStatements(outputLayout, mt)
+				statements, err := attestation.ExtractAnnotatedStatements(outputLayout, mt)
 				require.NoError(t, err)
 				allEnvelopes = append(allEnvelopes, statements...)

@@ -97,150 +74,9 @@ func TestSignVerifyOCILayout(t *testing.T) {
 				}
 			}
 			assert.Equalf(t, tc.expectedAttestations, len(allEnvelopes), "expected %d attestations, got %d", tc.expectedAttestations, len(allEnvelopes))
-			statements, err := test.ExtractAnnotatedStatements(outputLayout, intoto.PayloadType)
+			statements, err := attestation.ExtractAnnotatedStatements(outputLayout, intoto.PayloadType)
 			require.NoError(t, err)
 			assert.Equalf(t, tc.expectedStatements, len(statements), "expected %d statement, got %d", tc.expectedStatements, len(statements))
 		})
 	}
 }
-
-func TestAddSignedLayerAnnotations(t *testing.T) {
-	ctx, signer := test.Setup(t)
-	testCases := []struct {
-		name    string
-		replace bool
-	}{
-		{"replaced", true},
-		{"not replaced", false},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			data := []byte("signed")
-			testLayer := static.NewLayer(data, types.MediaType(intoto.PayloadType))
-			mediaType := types.OCIManifestSchema1
-			opts := &attestation.SigningOptions{}
-			originalLayer := &attestation.Layer{
-				Layer: testLayer,
-				Statement: &intoto.Statement{
-					StatementHeader: intoto.StatementHeader{
-						PredicateType: attestation.VSAPredicateType,
-					},
-				},
-				Annotations: map[string]string{"test": "test"},
-			}
-
-			manifest := &attestation.Manifest{
-				OriginalDescriptor: &v1.Descriptor{
-					MediaType: mediaType,
-				},
-				OriginalLayers: []*attestation.Layer{
-					originalLayer,
-				},
-				SubjectDescriptor: &v1.Descriptor{},
-			}
-			err := manifest.AddAttestation(ctx, signer, originalLayer.Statement, opts)
-			require.NoError(t, err)
-
-			newImg, err := manifest.BuildAttestationImage(attestation.WithReplacedLayers(tc.replace))
-			require.NoError(t, err)
-			mf, _ := newImg.RawManifest()
-			type Annotations struct {
-				Annotations map[string]string `json:"annotations"`
-			}
-			type Layers struct {
-				Layers []Annotations `json:"layers"`
-			}
-			l := &Layers{}
-			err = json.Unmarshal(mf, l)
-			require.NoError(t, err)
-			_, ok := l.Layers[0].Annotations["test"]
-			assert.Truef(t, ok, "missing annotations")
-		})
-	}
-}
-
-func TestSimpleStatementSigning(t *testing.T) {
-	ctx, signer := test.Setup(t)
-	empty := types.MediaType("application/vnd.oci.empty.v1+json")
-	testCases := []struct {
-		name    string
-		replace bool
-	}{
-		{"replaced", true},
-		{"not replaced", false},
-	}
-
-	for _, tc := range testCases {
-		t.Run(tc.name, func(t *testing.T) {
-			opts := &attestation.SigningOptions{}
-			statement := &intoto.Statement{
-				StatementHeader: intoto.StatementHeader{
-					PredicateType: attestation.VSAPredicateType,
-				},
-			}
-			statement2 := &intoto.Statement{
-				StatementHeader: intoto.StatementHeader{
-					PredicateType: attestation.VSAPredicateType,
-				},
-			}
-			digest, err := v1.NewHash("sha256:da8b190665956ea07890a0273e2a9c96bfe291662f08e2860e868eef69c34620")
-			require.NoError(t, err)
-			subject := &v1.Descriptor{
-				MediaType: "application/vnd.oci.image.manifest.v1+json",
-				Digest:    digest,
-			}
-			manifest, err := NewAttestationManifest(subject)
-			require.NoError(t, err)
-			err = manifest.AddAttestation(ctx, signer, statement, opts)
-			require.NoError(t, err)
-
-			err = manifest.AddAttestation(ctx, signer, statement2, opts)
-			require.NoError(t, err)
-
-			// fake that the manfifest was loaded from a real image
-			manifest.OriginalLayers = manifest.SignedLayers
-			envelopes, err := oci.ExtractEnvelopes(manifest, attestation.VSAPredicateType)
-			require.NoError(t, err)
-			assert.Len(t, envelopes, 2)
-
-			newImg, err := manifest.BuildAttestationImage(attestation.WithReplacedLayers(tc.replace))
-			require.NoError(t, err)
-			layers, err := newImg.Layers()
-			require.NoError(t, err)
-			if tc.replace {
-				assert.Len(t, layers, 2)
-			} else {
-				assert.Len(t, layers, 4)
-			}
-
-			newImgs, err := manifest.BuildReferringArtifacts()
-			require.NoError(t, err)
-			assert.Len(t, newImgs, 2)
-			for _, img := range newImgs {
-				mf, err := img.Manifest()
-				require.NoError(t, err)
-				assert.Contains(t, mf.ArtifactType, "application/vnd.in-toto")
-				assert.Contains(t, mf.ArtifactType, "+dsse")
-				assert.Equal(t, subject.MediaType, mf.MediaType)
-				assert.Equal(t, empty, mf.Config.MediaType)
-				assert.Equal(t, int64(2), mf.Config.Size)
-				assert.Equal(t, "{}", string(mf.Config.Data))
-				layers, err := img.Layers()
-				require.NoError(t, err)
-				assert.Len(t, layers, 1)
-			}
-			server := httptest.NewServer(registry.New(registry.WithReferrersSupport(true)))
-			defer server.Close()
-
-			u, err := url.Parse(server.URL)
-			require.NoError(t, err)
-
-			indexName := fmt.Sprintf("%s/repo:root", u.Host)
-			output, err := oci.ParseImageSpecs(indexName)
-			require.NoError(t, err)
-			err = mirror.SaveReferrers(manifest, output)
-			require.NoError(t, err)
-		})
-	}
-}
--- a/pkg/attest/verify.go
+++ b/pkg/attest/verify.go
@@ -11,7 +11,6 @@ import (
 	"github.com/docker/attest/pkg/config"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
-	v1 "github.com/google/go-containerregistry/pkg/v1"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 )

@@ -87,6 +86,8 @@ func toVerificationResult(p *policy.Policy, input *policy.Input, result *policy.
 		return nil, err
 	}

+	vsaPolicy := attestation.VSAPolicy{URI: result.Summary.PolicyURI, DownloadLocation: p.URI, Digest: p.Digest}
+
 	return &VerificationResult{
 		Policy:     p,
 		Outcome:    outcome,
@@ -104,7 +105,7 @@ func toVerificationResult(p *policy.Policy, input *policy.Input, result *policy.
 				},
 				TimeVerified:       time.Now().UTC().Format(time.RFC3339),
 				ResourceURI:        resourceURI,
-				Policy:             attestation.VSAPolicy{URI: result.Summary.PolicyURI},
+				Policy:             vsaPolicy,
 				VerificationResult: outcomeStr,
 				VerifiedLevels:     result.Summary.SLSALevels,
 			},
@@ -112,7 +113,7 @@ func toVerificationResult(p *policy.Policy, input *policy.Input, result *policy.
 	}, nil
 }

-func VerifyAttestations(ctx context.Context, resolver oci.AttestationResolver, pctx *policy.Policy) (*VerificationResult, error) {
+func VerifyAttestations(ctx context.Context, resolver attestation.Resolver, pctx *policy.Policy) (*VerificationResult, error) {
 	desc, err := resolver.ImageDescriptor(ctx)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get image descriptor: %w", err)
@@ -164,13 +165,3 @@ func VerifyAttestations(ctx context.Context, resolver oci.AttestationResolver, p
 	verificationResult.SubjectDescriptor = desc
 	return verificationResult, nil
 }
-
-func NewAttestationManifest(subject *v1.Descriptor) (*attestation.Manifest, error) {
-	return &attestation.Manifest{
-		OriginalDescriptor: &v1.Descriptor{
-			MediaType: "application/vnd.oci.image.manifest.v1+json",
-		},
-		OriginalLayers:    []*attestation.Layer{},
-		SubjectDescriptor: subject,
-	}, nil
-}
--- a/pkg/attest/verify_test.go
+++ b/pkg/attest/verify_test.go
@@ -10,12 +10,9 @@ import (

 	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/config"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
-	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/google/go-containerregistry/pkg/v1/empty"
-	"github.com/google/go-containerregistry/pkg/v1/layout"
-	"github.com/google/go-containerregistry/pkg/v1/mutate"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -34,7 +31,7 @@ func TestVerifyAttestations(t *testing.T) {
 	env := new(attestation.Envelope)
 	err = json.Unmarshal(ex, env)
 	assert.NoError(t, err)
-	resolver := &test.MockResolver{
+	resolver := &attestation.MockResolver{
 		Envs: []*attestation.Envelope{env},
 	}

@@ -50,7 +47,7 @@ func TestVerifyAttestations(t *testing.T) {
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			mockPE := policy.MockPolicyEvaluator{
-				EvaluateFunc: func(_ context.Context, _ oci.AttestationResolver, _ *policy.Policy, _ *policy.Input) (*policy.Result, error) {
+				EvaluateFunc: func(_ context.Context, _ attestation.Resolver, _ *policy.Policy, _ *policy.Input) (*policy.Result, error) {
 					return policy.AllowedResult(), tc.policyEvaluationError
 				},
 			}
@@ -75,7 +72,7 @@ func TestVSA(t *testing.T) {
 	outputLayout := test.CreateTempDir(t, "", TestTempDir)

 	opts := &attestation.SigningOptions{}
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	assert.NoError(t, err)
 	signedManifests, err := SignStatements(ctx, attIdx.Index, signer, opts)
 	require.NoError(t, err)
@@ -84,25 +81,17 @@ func TestVSA(t *testing.T) {
 	require.NoError(t, err)

 	// output signed attestations
-	idx := v1.ImageIndex(empty.Index)
-	idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
-		Add: signedIndex,
-		Descriptor: v1.Descriptor{
-			Annotations: map[string]string{
-				oci.OCIReferenceTarget: attIdx.Name,
-			},
-		},
-	})
-	_, err = layout.Write(outputLayout, idx)
+	spec, err := oci.ParseImageSpec(oci.LocalPrefix+outputLayout, oci.WithPlatform(LinuxAMD64))
+	require.NoError(t, err)
+	err = oci.SaveIndex([]*oci.ImageSpec{spec}, signedIndex, attIdx.Name)
 	assert.NoError(t, err)

 	// mocked vsa query should pass
 	policyOpts := &policy.Options{
-		LocalPolicyDir: PassPolicyDir,
+		LocalPolicyDir:   PassPolicyDir,
+		AttestationStyle: config.AttestationStyleAttached,
 	}
-	src, err := oci.ParseImageSpec("oci://"+outputLayout, oci.WithPlatform(LinuxAMD64))
-	require.NoError(t, err)
-	results, err := Verify(ctx, src, policyOpts)
+	results, err := Verify(ctx, spec, policyOpts)
 	require.NoError(t, err)
 	assert.Equal(t, OutcomeSuccess, results.Outcome)
 	assert.Empty(t, results.Violations)
@@ -123,7 +112,9 @@ func TestVSA(t *testing.T) {
 	assert.Equal(t, "PASSED", attestationPredicate.VerificationResult)
 	assert.Equal(t, "docker-official-images", attestationPredicate.Verifier.ID)
 	assert.Equal(t, []string{"SLSA_BUILD_LEVEL_3"}, attestationPredicate.VerifiedLevels)
+	assert.Equal(t, PassPolicyDir+"/policy.rego", attestationPredicate.Policy.DownloadLocation)
 	assert.Equal(t, "https://docker.com/official/policy/v0.1", attestationPredicate.Policy.URI)
+	assert.Equal(t, map[string]string{"sha256": "d71d6b8f49fcba1295b16f5394dd5863a14e4277eb663d66d8c48e392509afe0"}, attestationPredicate.Policy.Digest)
 }

 func TestVerificationFailure(t *testing.T) {
@@ -133,7 +124,7 @@ func TestVerificationFailure(t *testing.T) {
 	outputLayout := test.CreateTempDir(t, "", TestTempDir)

 	opts := &attestation.SigningOptions{}
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	assert.NoError(t, err)
 	signedManifests, err := SignStatements(ctx, attIdx.Index, signer, opts)
 	require.NoError(t, err)
@@ -142,25 +133,17 @@ func TestVerificationFailure(t *testing.T) {
 	require.NoError(t, err)

 	// output signed attestations
-	idx := v1.ImageIndex(empty.Index)
-	idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
-		Add: signedIndex,
-		Descriptor: v1.Descriptor{
-			Annotations: map[string]string{
-				oci.OCIReferenceTarget: attIdx.Name,
-			},
-		},
-	})
-	_, err = layout.Write(outputLayout, idx)
+	spec, err := oci.ParseImageSpec(oci.LocalPrefix+outputLayout, oci.WithPlatform(LinuxAMD64))
+	require.NoError(t, err)
+	err = oci.SaveIndex([]*oci.ImageSpec{spec}, signedIndex, attIdx.Name)
 	assert.NoError(t, err)

 	// mocked vsa query should fail
 	policyOpts := &policy.Options{
-		LocalPolicyDir: FailPolicyDir,
+		LocalPolicyDir:   FailPolicyDir,
+		AttestationStyle: config.AttestationStyleAttached,
 	}
-	src, err := oci.ParseImageSpec("oci://"+outputLayout, oci.WithPlatform(LinuxAMD64))
-	require.NoError(t, err)
-	results, err := Verify(ctx, src, policyOpts)
+	results, err := Verify(ctx, spec, policyOpts)
 	require.NoError(t, err)
 	assert.Equal(t, OutcomeFailure, results.Outcome)
 	assert.Len(t, results.Violations, 1)
@@ -181,7 +164,9 @@ func TestVerificationFailure(t *testing.T) {
 	assert.Equal(t, "FAILED", attestationPredicate.VerificationResult)
 	assert.Equal(t, "docker-official-images", attestationPredicate.Verifier.ID)
 	assert.Equal(t, []string{"SLSA_BUILD_LEVEL_3"}, attestationPredicate.VerifiedLevels)
+	assert.Equal(t, FailPolicyDir+"/policy.rego", attestationPredicate.Policy.DownloadLocation)
 	assert.Equal(t, "https://docker.com/official/policy/v0.1", attestationPredicate.Policy.URI)
+	assert.Equal(t, map[string]string{"sha256": "ad045e1bd7cd602d90196acf68f2c57d7b51565d59e6e30e30d94ae86aa16201"}, attestationPredicate.Policy.Digest)
 }

 func TestSignVerify(t *testing.T) {
@@ -204,7 +189,7 @@ func TestSignVerify(t *testing.T) {
 		{name: "mirror no match", signTL: true, policyDir: PassMirrorPolicyDir, imageName: "incorrect.org/library/test-image:test", expectError: true},
 	}

-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	assert.NoError(t, err)

 	for _, tc := range testCases {
@@ -224,24 +209,15 @@ func TestSignVerify(t *testing.T) {
 				imageName = attIdx.Name
 			}
 			// output signed attestations
-			idx := v1.ImageIndex(empty.Index)
-			idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
-				Add: signedIndex,
-				Descriptor: v1.Descriptor{
-					Annotations: map[string]string{
-						oci.OCIReferenceTarget: imageName,
-					},
-				},
-			})
-			_, err = layout.Write(outputLayout, idx)
-			assert.NoError(t, err)
+			spec, err := oci.ParseImageSpec(oci.LocalPrefix+outputLayout, oci.WithPlatform(LinuxAMD64))
+			require.NoError(t, err)
+			err = oci.SaveIndex([]*oci.ImageSpec{spec}, signedIndex, imageName)
+			require.NoError(t, err)

 			policyOpts := &policy.Options{
 				LocalPolicyDir: tc.policyDir,
 			}
-			src, err := oci.ParseImageSpec("oci://"+outputLayout, oci.WithPlatform(LinuxAMD64))
-			require.NoError(t, err)
-			results, err := Verify(ctx, src, policyOpts)
+			results, err := Verify(ctx, spec, policyOpts)
 			if tc.expectError {
 				require.Error(t, err)
 				return
--- a/pkg/attestation/README.md
+++ b/pkg/attestation/README.md
@@ -0,0 +1,4 @@
+## attestations
+This package is for components that deal with the creation, storage, and retrieval of signed attestions using OCI. 
+
+For more generic OCI components see the `oci` package.
--- a/pkg/attestation/attestation.go
+++ b/pkg/attestation/attestation.go
@@ -2,12 +2,16 @@ package attestation

 import (
 	"context"
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"maps"
+	"strings"

+	"github.com/docker/attest/pkg/oci"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/empty"
+	"github.com/google/go-containerregistry/pkg/v1/layout"
 	"github.com/google/go-containerregistry/pkg/v1/match"
 	"github.com/google/go-containerregistry/pkg/v1/mutate"
 	"github.com/google/go-containerregistry/pkg/v1/partial"
@@ -17,8 +21,19 @@ import (
 	"github.com/secure-systems-lab/go-securesystemslib/dsse"
 )

-// GetAttestationManifestsFromIndex extracts all attestation manifests from an index.
-func GetAttestationManifestsFromIndex(index v1.ImageIndex) ([]*Manifest, error) {
+// NewManifest creates a new attestation manifest from a descriptor.
+func NewManifest(subject *v1.Descriptor) (*Manifest, error) {
+	return &Manifest{
+		OriginalDescriptor: &v1.Descriptor{
+			MediaType: "application/vnd.oci.image.manifest.v1+json",
+		},
+		OriginalLayers:    []*Layer{},
+		SubjectDescriptor: subject,
+	}, nil
+}
+
+// ManifestsFromIndex extracts all attestation manifests from an index.
+func ManifestsFromIndex(index v1.ImageIndex) ([]*Manifest, error) {
 	idx, err := index.IndexManifest()
 	if err != nil {
 		return nil, fmt.Errorf("failed to extract IndexManifest from ImageIndex: %w", err)
@@ -41,7 +56,7 @@ func GetAttestationManifestsFromIndex(index v1.ImageIndex) ([]*Manifest, error)
 			if err != nil {
 				return nil, fmt.Errorf("failed to extract attestation image with digest %s: %w", desc.Digest.String(), err)
 			}
-			attestationLayers, err := GetAttestationsFromImage(attestationImage)
+			attestationLayers, err := layersFromImage(attestationImage)
 			if err != nil {
 				return nil, fmt.Errorf("failed to get attestations from image: %w", err)
 			}
@@ -56,8 +71,8 @@ func GetAttestationManifestsFromIndex(index v1.ImageIndex) ([]*Manifest, error)
 	return attestationManifests, nil
 }

-// GetAttestationsFromImage extracts all attestation layers from an image.
-func GetAttestationsFromImage(image v1.Image) ([]*Layer, error) {
+// LayersFromImage extracts all attestation layers from an image.
+func layersFromImage(image v1.Image) ([]*Layer, error) {
 	layers, err := image.Layers()
 	if err != nil {
 		return nil, fmt.Errorf("failed to extract layers from image: %w", err)
@@ -93,7 +108,7 @@ func GetAttestationsFromImage(image v1.Image) ([]*Layer, error) {
 	return attestationLayers, nil
 }

-func (manifest *Manifest) AddAttestation(ctx context.Context, signer dsse.SignerVerifier, statement *intoto.Statement, opts *SigningOptions) error {
+func (manifest *Manifest) Add(ctx context.Context, signer dsse.SignerVerifier, statement *intoto.Statement, opts *SigningOptions) error {
 	layer, err := createSignedImageLayer(ctx, statement, signer, opts)
 	if err != nil {
 		return fmt.Errorf("failed to create signed layer: %w", err)
@@ -104,7 +119,7 @@ func (manifest *Manifest) AddAttestation(ctx context.Context, signer dsse.Signer

 func createSignedImageLayer(ctx context.Context, statement *intoto.Statement, signer dsse.SignerVerifier, opts *SigningOptions) (*Layer, error) {
 	// sign the statement
-	env, err := SignInTotoStatement(ctx, statement, signer, opts)
+	env, err := signInTotoStatement(ctx, statement, signer, opts)
 	if err != nil {
 		return nil, fmt.Errorf("failed to sign statement: %w", err)
 	}
@@ -127,7 +142,7 @@ func createSignedImageLayer(ctx context.Context, statement *intoto.Statement, si
 	}, nil
 }

-func SignInTotoStatement(ctx context.Context, statement *intoto.Statement, signer dsse.SignerVerifier, opts *SigningOptions) (*Envelope, error) {
+func signInTotoStatement(ctx context.Context, statement *intoto.Statement, signer dsse.SignerVerifier, opts *SigningOptions) (*Envelope, error) {
 	payload, err := json.Marshal(statement)
 	if err != nil {
 		return nil, fmt.Errorf("failed to marshal statement: %w", err)
@@ -139,12 +154,12 @@ func SignInTotoStatement(ctx context.Context, statement *intoto.Statement, signe
 	return env, nil
 }

-func UpdateIndexImage(
+func updateImageIndex(
 	idx v1.ImageIndex,
 	manifest *Manifest,
 	options ...func(*ManifestImageOptions) error,
 ) (v1.ImageIndex, error) {
-	image, err := manifest.BuildAttestationImage(options...)
+	image, err := manifest.BuildImage(options...)
 	if err != nil {
 		return nil, fmt.Errorf("failed to build image: %w", err)
 	}
@@ -169,7 +184,7 @@ func UpdateIndexImage(
 func UpdateIndexImages(idx v1.ImageIndex, manifest []*Manifest, options ...func(*ManifestImageOptions) error) (v1.ImageIndex, error) {
 	var err error
 	for _, m := range manifest {
-		idx, err = UpdateIndexImage(idx, m, options...)
+		idx, err = updateImageIndex(idx, m, options...)
 		if err != nil {
 			return nil, fmt.Errorf("failed to add image to index: %w", err)
 		}
@@ -203,7 +218,7 @@ func WithReplacedLayers(replaceLayers bool) func(*ManifestImageOptions) error {
 }

 // build an image with signed attestations, optionally replacing existing layers with signed layers.
-func (manifest *Manifest) BuildAttestationImage(options ...func(*ManifestImageOptions) error) (v1.Image, error) {
+func (manifest *Manifest) BuildImage(options ...func(*ManifestImageOptions) error) (v1.Image, error) {
 	opts, err := newOptions(options...)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create options: %w", err)
@@ -228,7 +243,7 @@ func (manifest *Manifest) BuildAttestationImage(options ...func(*ManifestImageOp
 	}
 	// so that we attach all attestations to a single attestations image - as per current buildkit
 	opts.laxReferrers = true
-	newImg, err := buildImage(resultLayers, manifest.OriginalDescriptor, manifest.SubjectDescriptor, opts)
+	newImg, err := buildImageFromLayers(resultLayers, manifest.OriginalDescriptor, manifest.SubjectDescriptor, opts)
 	if err != nil {
 		return nil, fmt.Errorf("failed to build image: %w", err)
 	}
@@ -240,7 +255,7 @@ func (manifest *Manifest) BuildReferringArtifacts() ([]v1.Image, error) {
 	var images []v1.Image
 	for _, layer := range manifest.SignedLayers {
 		opts := &ManifestImageOptions{}
-		newImg, err := buildImage([]*Layer{layer}, manifest.OriginalDescriptor, manifest.SubjectDescriptor, opts)
+		newImg, err := buildImageFromLayers([]*Layer{layer}, manifest.OriginalDescriptor, manifest.SubjectDescriptor, opts)
 		if err != nil {
 			return nil, fmt.Errorf("failed to build image: %w", err)
 		}
@@ -249,8 +264,8 @@ func (manifest *Manifest) BuildReferringArtifacts() ([]v1.Image, error) {
 	return images, nil
 }

-// build and image containing only layers.
-func buildImage(layers []*Layer, manifest *v1.Descriptor, subject *v1.Descriptor, opts *ManifestImageOptions) (v1.Image, error) {
+// build an image containing only layers provided.
+func buildImageFromLayers(layers []*Layer, manifest *v1.Descriptor, subject *v1.Descriptor, opts *ManifestImageOptions) (v1.Image, error) {
 	newImg := empty.Image
 	var err error
 	if len(layers) == 0 {
@@ -295,37 +310,135 @@ func buildImage(layers []*Layer, manifest *v1.Descriptor, subject *v1.Descriptor
 	}
 	if !opts.laxReferrers {
 		// as per https://github.com/opencontainers/image-spec/blob/main/manifest.md#guidance-for-an-empty-descriptor
-		newImg = &EmptyConfigImage{newImg}
+		newImg = &oci.EmptyConfigImage{Image: newImg}
 	}
 	return newImg, nil
 }

-type EmptyConfigImage struct {
-	v1.Image
-}
-
-func (i *EmptyConfigImage) RawConfigFile() ([]byte, error) {
-	return []byte("{}"), nil
-}
-
-func (i *EmptyConfigImage) Manifest() (*v1.Manifest, error) {
-	mf, err := i.Image.Manifest()
+func ExtractEnvelopes(manifest *Manifest, predicateType string) ([]*Envelope, error) {
+	var envs []*Envelope
+	dsseMediaType, err := DSSEMediaType(predicateType)
 	if err != nil {
-		return nil, fmt.Errorf("failed to get manifest: %w", err)
+		return nil, fmt.Errorf("failed to get DSSE media type for predicate '%s': %w", predicateType, err)
 	}
-	mf.Config = v1.Descriptor{
-		MediaType: "application/vnd.oci.empty.v1+json",
-		Size:      2,
-		Digest:    v1.Hash{Algorithm: "sha256", Hex: "44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a"},
-		Data:      []byte("{}"),
+	for _, attestationLayer := range manifest.OriginalLayers {
+		mt, err := attestationLayer.Layer.MediaType()
+		if err != nil {
+			return nil, fmt.Errorf("failed to get layer media type: %w", err)
+		}
+		if string(mt) == dsseMediaType {
+			reader, err := attestationLayer.Layer.Uncompressed()
+			if err != nil {
+				return nil, fmt.Errorf("failed to get layer contents: %w", err)
+			}
+			defer reader.Close()
+			env := new(Envelope)
+			err = json.NewDecoder(reader).Decode(&env)
+			if err != nil {
+				return nil, fmt.Errorf("failed to decode envelope: %w", err)
+			}
+			envs = append(envs, env)
+		}
 	}
-	return mf, nil
+
+	return envs, nil
 }

-func (i *EmptyConfigImage) RawManifest() ([]byte, error) {
-	mf, err := i.Manifest()
+func ExtractStatementsFromIndex(idx v1.ImageIndex, mediaType string) ([]*AnnotatedStatement, error) {
+	mfs2, err := idx.IndexManifest()
 	if err != nil {
-		return nil, fmt.Errorf("failed to get manifest: %w", err)
+		return nil, fmt.Errorf("failed to extract IndexManifest from ImageIndex: %w", err)
 	}
-	return json.Marshal(mf)
+
+	var statements []*AnnotatedStatement
+
+	for i := range mfs2.Manifests {
+		mf := &mfs2.Manifests[i]
+		if mf.Annotations[DockerReferenceType] != "attestation-manifest" {
+			continue
+		}
+
+		attestationImage, err := idx.Image(mf.Digest)
+		if err != nil {
+			return nil, fmt.Errorf("failed to extract attestation image with digest %s: %w", mf.Digest.String(), err)
+		}
+		layers, err := attestationImage.Layers()
+		if err != nil {
+			return nil, fmt.Errorf("failed to extract layers from attestation image: %w", err)
+		}
+
+		for _, layer := range layers {
+			// parse layer blob as json
+			mt, err := layer.MediaType()
+			if err != nil {
+				return nil, fmt.Errorf("failed to get layer media type: %w", err)
+			}
+
+			if string(mt) != mediaType {
+				continue
+			}
+			r, err := layer.Uncompressed()
+			if err != nil {
+				return nil, fmt.Errorf("failed to get layer contents: %w", err)
+			}
+			defer r.Close()
+			inTotoStatement := new(intoto.Statement)
+			var desc *v1.Descriptor
+			if strings.HasSuffix(string(mt), "+dsse") {
+				env := new(Envelope)
+				err = json.NewDecoder(r).Decode(env)
+				if err != nil {
+					return nil, fmt.Errorf("failed to decode env: %w", err)
+				}
+				payload, err := base64.StdEncoding.Strict().DecodeString(env.Payload)
+				if err != nil {
+					return nil, fmt.Errorf("failed to decode payload: %w", err)
+				}
+				err = json.Unmarshal([]byte(payload), inTotoStatement)
+				if err != nil {
+					return nil, fmt.Errorf("failed to decode %s statement: %w", mediaType, err)
+				}
+			} else {
+				desc := new(v1.Descriptor)
+				err = json.NewDecoder(r).Decode(desc)
+				if err != nil {
+					return nil, fmt.Errorf("failed to decode statement: %w", err)
+				}
+			}
+
+			layerDesc, err := partial.Descriptor(layer)
+			if err != nil {
+				return nil, fmt.Errorf("failed to get descriptor for layer: %w", err)
+			}
+			annotations := make(map[string]string)
+			for k, v := range layerDesc.Annotations {
+				annotations[k] = v
+			}
+			statements = append(statements, &AnnotatedStatement{
+				OCIDescriptor:   desc,
+				InTotoStatement: inTotoStatement,
+				Annotations:     annotations,
+			})
+		}
+	}
+	return statements, nil
+}
+
+func ExtractAnnotatedStatements(path string, mediaType string) ([]*AnnotatedStatement, error) {
+	idx, err := layout.ImageIndexFromPath(path)
+	if err != nil {
+		return nil, fmt.Errorf("failed to load image index: %w", err)
+	}
+
+	idxm, err := idx.IndexManifest()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get digest: %w", err)
+	}
+	idxDigest := idxm.Manifests[0].Digest
+
+	mfs, err := idx.ImageIndex(idxDigest)
+	if err != nil {
+		return nil, fmt.Errorf("failed to extract ImageIndex for digest %s: %w", idxDigest.String(), err)
+	}
+	return ExtractStatementsFromIndex(mfs, mediaType)
 }
--- a/pkg/attestation/attestation_test.go
+++ b/pkg/attestation/attestation_test.go
@@ -1,21 +1,18 @@
-package test
+package attestation_test

 import (
-	"path/filepath"
 	"testing"

+	"github.com/docker/attest/internal/test"
+	"github.com/docker/attest/pkg/attestation"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	"github.com/stretchr/testify/assert"
 )

-var UnsignedTestImage = filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
-
-const (
-	ExpectedStatements = 4
-)
+const ExpectedStatements = 4

 func TestExtractAnnotatedStatements(t *testing.T) {
-	statements, err := ExtractAnnotatedStatements(UnsignedTestImage, intoto.PayloadType)
+	statements, err := attestation.ExtractAnnotatedStatements(test.UnsignedTestImage, intoto.PayloadType)
 	assert.NoError(t, err)
 	assert.Equalf(t, len(statements), ExpectedStatements, "expected %d statement, got %d", ExpectedStatements, len(statements))
 }
--- a/pkg/attestation/example_attestation_manifest_test.go
+++ b/pkg/attestation/example_attestation_manifest_test.go
@@ -4,9 +4,7 @@ import (
 	"context"
 	"time"

-	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/mirror"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/signerverifier"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
@@ -63,13 +61,13 @@ func ExampleManifest() {
 	}

 	// create a new manifest to hold the attestation
-	manifest, err := attest.NewAttestationManifest(desc)
+	manifest, err := attestation.NewManifest(desc)
 	if err != nil {
 		panic(err)
 	}

 	// sign and add the attestation to the manifest
-	err = manifest.AddAttestation(context.Background(), signer, statement, opts)
+	err = manifest.Add(context.Background(), signer, statement, opts)
 	if err != nil {
 		panic(err)
 	}
@@ -80,7 +78,11 @@ func ExampleManifest() {
 	}

 	// save the manifest to the registry as a referrers artifact
-	err = mirror.SaveReferrers(manifest, output)
+	artifacts, err := manifest.BuildReferringArtifacts()
+	if err != nil {
+		panic(err)
+	}
+	err = oci.SaveImagesNoTag(artifacts, output)
 	if err != nil {
 		panic(err)
 	}
--- a/pkg/attestation/layout.go
+++ b/pkg/attestation/layout.go
@@ -1,36 +1,35 @@
-package oci
+package attestation

 import (
 	"context"
 	"encoding/json"
 	"fmt"

-	"github.com/docker/attest/pkg/attestation"
-	att "github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/layout"
 )

-// implementation of AttestationResolver that closes over attestations from an oci layout.
+// implementation of Resolver that closes over attestations from an oci layout.
 type LayoutResolver struct {
-	*attestation.Manifest
-	*ImageSpec
+	*Manifest
+	*oci.ImageSpec
 }

-func NewOCILayoutAttestationResolver(src *ImageSpec) (*LayoutResolver, error) {
+func NewOCILayoutResolver(src *oci.ImageSpec) (*LayoutResolver, error) {
 	r := &LayoutResolver{
 		ImageSpec: src,
 	}
-	_, err := r.fetchAttestationManifest()
+	_, err := r.fetchManifest()
 	if err != nil {
 		return nil, err
 	}
 	return r, nil
 }

-func (r *LayoutResolver) fetchAttestationManifest() (*attestation.Manifest, error) {
+func (r *LayoutResolver) fetchManifest() (*Manifest, error) {
 	if r.Manifest == nil {
-		m, err := attestationManifestFromOCILayout(r.Identifier, r.ImageSpec.Platform)
+		m, err := manifestFromOCILayout(r.Identifier, r.ImageSpec.Platform)
 		if err != nil {
 			return nil, err
 		}
@@ -40,9 +39,9 @@ func (r *LayoutResolver) fetchAttestationManifest() (*attestation.Manifest, erro
 	return r.Manifest, nil
 }

-func (r *LayoutResolver) Attestations(_ context.Context, predicateType string) ([]*att.Envelope, error) {
-	var envs []*att.Envelope
-	dsseMediaType, err := attestation.DSSEMediaType(predicateType)
+func (r *LayoutResolver) Attestations(_ context.Context, predicateType string) ([]*Envelope, error) {
+	var envs []*Envelope
+	dsseMediaType, err := DSSEMediaType(predicateType)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get DSSE media type for predicate '%s': %w", predicateType, err)
 	}
@@ -55,7 +54,7 @@ func (r *LayoutResolver) Attestations(_ context.Context, predicateType string) (
 		if mts != dsseMediaType {
 			continue
 		}
-		env := new(att.Envelope)
+		env := new(Envelope)
 		// parse layer blob as json
 		r, err := attestationLayer.Layer.Uncompressed()
 		if err != nil {
@@ -83,7 +82,7 @@ func (r *LayoutResolver) ImagePlatform(_ context.Context) (*v1.Platform, error)
 	return r.ImageSpec.Platform, nil
 }

-func attestationManifestFromOCILayout(path string, platform *v1.Platform) (*attestation.Manifest, error) {
+func manifestFromOCILayout(path string, platform *v1.Platform) (*Manifest, error) {
 	idx, err := layout.ImageIndexFromPath(path)
 	if err != nil {
 		return nil, err
@@ -95,7 +94,6 @@ func attestationManifestFromOCILayout(path string, platform *v1.Platform) (*atte
 	}

 	idxDescriptor := idxm.Manifests[0]
-	name := idxDescriptor.Annotations["org.opencontainers.image.ref.name"]
 	idxDigest := idxDescriptor.Digest

 	mfs, err := idx.ImageIndex(idxDigest)
@@ -109,18 +107,23 @@ func attestationManifestFromOCILayout(path string, platform *v1.Platform) (*atte
 	var subjectDescriptor *v1.Descriptor
 	for i := range mfs2.Manifests {
 		manifest := &mfs2.Manifests[i]
-		if manifest.Platform.Equals(*platform) {
-			subjectDescriptor = manifest
-			break
+		if manifest.Platform != nil {
+			if manifest.Platform.Equals(*platform) {
+				subjectDescriptor = manifest
+				break
+			}
 		}
 	}
+	if subjectDescriptor == nil {
+		return nil, fmt.Errorf("platform not found in index")
+	}
 	for i := range mfs2.Manifests {
 		mf := &mfs2.Manifests[i]
-		if mf.Annotations[att.DockerReferenceType] != attestation.AttestationManifestType {
+		if mf.Annotations[DockerReferenceType] != AttestationManifestType {
 			continue
 		}

-		if mf.Annotations[att.DockerReferenceDigest] != subjectDescriptor.Digest.String() {
+		if mf.Annotations[DockerReferenceDigest] != subjectDescriptor.Digest.String() {
 			continue
 		}

@@ -128,14 +131,14 @@ func attestationManifestFromOCILayout(path string, platform *v1.Platform) (*atte
 		if err != nil {
 			return nil, fmt.Errorf("failed to extract attestation image with digest %s: %w", mf.Digest.String(), err)
 		}
-		layers, err := attestation.GetAttestationsFromImage(attestationImage)
+		layers, err := layersFromImage(attestationImage)
 		if err != nil {
 			return nil, fmt.Errorf("failed to get attestations from image: %w", err)
 		}
-		attest := &attestation.Manifest{
+		attest := &Manifest{
 			OriginalLayers:     layers,
 			OriginalDescriptor: mf,
-			SubjectName:        name,
+			SubjectName:        idxDescriptor.Annotations["org.opencontainers.image.ref.name"],
 			SubjectDescriptor:  subjectDescriptor,
 		}
 		return attest, nil
--- a/pkg/attestation/layout_test.go
+++ b/pkg/attestation/layout_test.go
@@ -0,0 +1,68 @@
+package attestation_test
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/docker/attest/internal/test"
+	"github.com/docker/attest/pkg/attest"
+	"github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
+	"github.com/docker/attest/pkg/policy"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestAttestationFromOCILayout(t *testing.T) {
+	ctx, signer := test.Setup(t)
+	outputLayout := test.CreateTempDir(t, "", "attest-oci-layout")
+
+	invalidPlatform := &v1.Platform{
+		Architecture: "invalid",
+		OS:           "invalid",
+	}
+
+	opts := &attestation.SigningOptions{}
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
+	require.NoError(t, err)
+	signedManifests, err := attest.SignStatements(ctx, attIdx.Index, signer, opts)
+	require.NoError(t, err)
+	signedIndex := attIdx.Index
+	signedIndex, err = attestation.UpdateIndexImages(signedIndex, signedManifests)
+	require.NoError(t, err)
+	spec, err := oci.ParseImageSpec(oci.LocalPrefix + outputLayout)
+	require.NoError(t, err)
+	err = oci.SaveIndex([]*oci.ImageSpec{spec}, signedIndex, outputLayout)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		name     string
+		platform *v1.Platform
+		errorStr string
+	}{
+		{name: "nominal", platform: spec.Platform},
+		{name: "invalid platform", platform: invalidPlatform, errorStr: "platform not found in index"},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			spec := &oci.ImageSpec{
+				Type:       oci.OCI,
+				Identifier: outputLayout,
+				Platform:   tc.platform,
+			}
+			resolver, err := policy.CreateImageDetailsResolver(spec)
+			if tc.errorStr != "" {
+				require.Error(t, err)
+				assert.Contains(t, err.Error(), tc.errorStr)
+				return
+			}
+			require.NoError(t, err)
+			desc, err := resolver.ImageDescriptor(ctx)
+			require.NoError(t, err)
+			digest := desc.Digest.String()
+			assert.True(t, strings.Contains(digest, "sha256:"))
+		})
+	}
+}
--- a/pkg/attestation/mock.go
+++ b/pkg/attestation/mock.go
@@ -1,22 +1,17 @@
-package test
+package attestation

 import (
 	"context"
-	"os"
-	"path/filepath"

-	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/oci"
-	"github.com/docker/attest/pkg/signerverifier"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/secure-systems-lab/go-securesystemslib/dsse"
 )

 type MockResolver struct {
-	Envs []*attestation.Envelope
+	Envs []*Envelope
 }

-func (r MockResolver) Attestations(_ context.Context, _ string) ([]*attestation.Envelope, error) {
+func (r MockResolver) Attestations(_ context.Context, _ string) ([]*Envelope, error) {
 	return r.Envs, nil
 }

@@ -53,11 +48,3 @@ func (r *MockRegistryResolver) ImageDescriptor(_ context.Context) (*v1.Descripto
 func (r *MockRegistryResolver) ImageName(_ context.Context) (string, error) {
 	return r.ImageNameStr, nil
 }
-
-func GetMockSigner(_ context.Context) (dsse.SignerVerifier, error) {
-	priv, err := os.ReadFile(filepath.Join("..", "..", "test", "testdata", "test-signing-key.pem"))
-	if err != nil {
-		return nil, err
-	}
-	return signerverifier.LoadKeyPair(priv)
-}
--- a/pkg/attestation/referrers.go
+++ b/pkg/attestation/referrers.go
@@ -1,21 +1,21 @@
-package oci
+package attestation

 import (
 	"context"
 	"fmt"
+	"strings"

-	"github.com/docker/attest/pkg/attestation"
-	att "github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
 	"github.com/google/go-containerregistry/pkg/name"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 )

 type ReferrersResolver struct {
 	referrersRepo string
-	ImageDetailsResolver
+	oci.ImageDetailsResolver
 }

-func NewReferrersAttestationResolver(src ImageDetailsResolver, options ...func(*ReferrersResolver) error) (*ReferrersResolver, error) {
+func NewReferrersResolver(src oci.ImageDetailsResolver, options ...func(*ReferrersResolver) error) (*ReferrersResolver, error) {
 	res := &ReferrersResolver{
 		ImageDetailsResolver: src,
 	}
@@ -35,8 +35,8 @@ func WithReferrersRepo(repo string) func(*ReferrersResolver) error {
 	}
 }

-func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateType string) ([]*attestation.Manifest, error) {
-	dsseMediaType, err := attestation.DSSEMediaType(predicateType)
+func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateType string) ([]*Manifest, error) {
+	dsseMediaType, err := DSSEMediaType(predicateType)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get DSSE media type for predicate '%s': %w", predicateType, err)
 	}
@@ -53,19 +53,16 @@ func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateTy
 		return nil, fmt.Errorf("failed to get descriptor: %w", err)
 	}
 	subjectDigest := desc.Digest.String()
-	if err != nil {
-		return nil, fmt.Errorf("failed to get digest: %w", err)
-	}
 	var referrersSubjectRef name.Digest
 	if r.referrersRepo != "" {
-		referrersSubjectRef, err = name.NewDigest(fmt.Sprintf("%s@%s", r.referrersRepo, subjectDigest))
+		referrersSubjectRef, err = name.NewDigest(fmt.Sprintf("%s@%s", strings.TrimPrefix(r.referrersRepo, oci.RegistryPrefix), subjectDigest))
 		if err != nil {
 			return nil, fmt.Errorf("failed to create referrers reference: %w", err)
 		}
 	} else {
 		referrersSubjectRef = subjectRef.Context().Digest(subjectDigest)
 	}
-	options := WithOptions(ctx, nil)
+	options := oci.WithOptions(ctx, nil)
 	options = append(options, remote.WithFilter("artifactType", dsseMediaType))
 	referrersIndex, err := remote.Referrers(referrersSubjectRef, options...)
 	if err != nil {
@@ -75,16 +72,16 @@ func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateTy
 	if err != nil {
 		return nil, fmt.Errorf("failed to get index manifest: %w", err)
 	}
-	aManifests := make([]*attestation.Manifest, 0)
+	aManifests := make([]*Manifest, 0)
 	for i := range referrersIndexManifest.Manifests {
 		m := referrersIndexManifest.Manifests[i]
 		remoteRef := referrersSubjectRef.Context().Digest(m.Digest.String())
-		options = WithOptions(ctx, nil)
+		options = oci.WithOptions(ctx, nil)
 		attestationImage, err := remote.Image(remoteRef, options...)
 		if err != nil {
 			return nil, fmt.Errorf("failed to get referred image: %w", err)
 		}
-		layers, err := attestation.GetAttestationsFromImage(attestationImage)
+		layers, err := layersFromImage(attestationImage)
 		if err != nil {
 			return nil, fmt.Errorf("failed to get attestations from image: %w", err)
 		}
@@ -98,7 +95,7 @@ func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateTy
 		if string(mt) != dsseMediaType {
 			return nil, fmt.Errorf("expected layer media type %s, got %s", dsseMediaType, mt)
 		}
-		attest := &attestation.Manifest{
+		attest := &Manifest{
 			SubjectName:        imageName,
 			OriginalLayers:     layers,
 			OriginalDescriptor: &m,
@@ -109,12 +106,12 @@ func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateTy
 	return aManifests, nil
 }

-func (r *ReferrersResolver) Attestations(ctx context.Context, predicateType string) ([]*att.Envelope, error) {
+func (r *ReferrersResolver) Attestations(ctx context.Context, predicateType string) ([]*Envelope, error) {
 	manifests, err := r.resolveAttestations(ctx, predicateType)
 	if err != nil {
 		return nil, fmt.Errorf("failed to resolve attestations: %w", err)
 	}
-	var envs []*att.Envelope
+	var envs []*Envelope
 	for _, attest := range manifests {
 		es, err := ExtractEnvelopes(attest, predicateType)
 		if err != nil {
--- a/pkg/attestation/referrers_test.go
+++ b/pkg/attestation/referrers_test.go
@@ -11,7 +11,6 @@ import (
 	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/config"
-	"github.com/docker/attest/pkg/mirror"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
 	"github.com/google/go-containerregistry/pkg/name"
@@ -22,7 +21,6 @@ import (
 )

 var (
-	UnsignedTestImage   = filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
 	NoProvenanceImage   = filepath.Join("..", "..", "test", "testdata", "no-provenance-image")
 	PassPolicyDir       = filepath.Join("..", "..", "test", "testdata", "local-policy-pass")
 	LocalPolicy         = filepath.Join("..", "..", "test", "testdata", "local-policy")
@@ -93,7 +91,7 @@ func TestAttestationReferenceTypes(t *testing.T) {
 			opts := &attestation.SigningOptions{
 				SkipTL: true,
 			}
-			attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+			attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 			require.NoError(t, err)

 			indexName := fmt.Sprintf("%s/repo:root", u.Host)
@@ -112,14 +110,16 @@ func TestAttestationReferenceTypes(t *testing.T) {

 			// push subject image so that it can be resolved
 			require.NoError(t, err)
-			err = mirror.PushIndexToRegistry(attIdx.Index, indexName)
+			err = oci.PushIndexToRegistry(attIdx.Index, indexName)
 			require.NoError(t, err)

 			// upload referrers
 			output, err := oci.ParseImageSpec(outputRepo)
 			require.NoError(t, err)
 			for _, attIdx := range signedManifests {
-				err = mirror.SaveReferrers(attIdx, []*oci.ImageSpec{output})
+				images, err := attIdx.BuildReferringArtifacts()
+				require.NoError(t, err)
+				err = oci.SaveImagesNoTag(images, []*oci.ImageSpec{output})
 				require.NoError(t, err)
 			}

@@ -212,11 +212,11 @@ func TestReferencesInDifferentRepo(t *testing.T) {
 		opts := &attestation.SigningOptions{
 			SkipTL: true,
 		}
-		attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+		attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 		require.NoError(t, err)

 		indexName := fmt.Sprintf("%s/%s:latest", serverURL.Host, repoName)
-		err = mirror.PushIndexToRegistry(attIdx.Index, indexName)
+		err = oci.PushIndexToRegistry(attIdx.Index, indexName)
 		require.NoError(t, err)

 		signedManifests, err := attest.SignStatements(ctx, attIdx.Index, signer, opts)
@@ -225,9 +225,9 @@ func TestReferencesInDifferentRepo(t *testing.T) {
 		// push signed attestation image to the ref server
 		for _, signedManifest := range signedManifests {
 			// push references using subject-digest.att convention
-			image, err := signedManifest.BuildAttestationImage()
+			image, err := signedManifest.BuildImage()
 			require.NoError(t, err)
-			err = mirror.PushImageToRegistry(image, fmt.Sprintf("%s/%s:tag-does-not-matter", refServerURL.Host, repoName))
+			err = oci.PushImageToRegistry(image, fmt.Sprintf("%s/%s:tag-does-not-matter", refServerURL.Host, repoName))
 			require.NoError(t, err)

 			refServer := tc.refServer
@@ -238,11 +238,11 @@ func TestReferencesInDifferentRepo(t *testing.T) {
 			opts := &attestation.SigningOptions{
 				SkipTL: true,
 			}
-			attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+			attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 			require.NoError(t, err)

 			indexName := fmt.Sprintf("%s/%s:latest", serverURL.Host, repoName)
-			err = mirror.PushIndexToRegistry(attIdx.Index, indexName)
+			err = oci.PushIndexToRegistry(attIdx.Index, indexName)
 			require.NoError(t, err)

 			signedManifests, err := attest.SignStatements(ctx, attIdx.Index, signer, opts)
@@ -254,7 +254,7 @@ func TestReferencesInDifferentRepo(t *testing.T) {
 				imgs, err := mf.BuildReferringArtifacts()
 				require.NoError(t, err)
 				for _, img := range imgs {
-					err = mirror.PushImageToRegistry(img, fmt.Sprintf("%s/%s:tag-does-not-matter", refServerURL.Host, repoName))
+					err = oci.PushImageToRegistry(img, fmt.Sprintf("%s/%s:tag-does-not-matter", refServerURL.Host, repoName))
 					require.NoError(t, err)
 				}
 			}
@@ -293,11 +293,11 @@ func TestCorrectArtifactTypeInTagFallback(t *testing.T) {
 	opts := &attestation.SigningOptions{
 		SkipTL: true,
 	}
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	require.NoError(t, err)

 	indexName := fmt.Sprintf("%s/%s:latest", serverURL.Host, repoName)
-	err = mirror.PushIndexToRegistry(attIdx.Index, indexName)
+	err = oci.PushIndexToRegistry(attIdx.Index, indexName)
 	require.NoError(t, err)

 	signedManifests, err := attest.SignStatements(ctx, attIdx.Index, signer, opts)
@@ -308,7 +308,7 @@ func TestCorrectArtifactTypeInTagFallback(t *testing.T) {
 		imgs, err := mf.BuildReferringArtifacts()
 		require.NoError(t, err)
 		for _, img := range imgs {
-			err = mirror.PushImageToRegistry(img, fmt.Sprintf("%s/%s:tag-does-not-matter", serverURL.Host, repoName))
+			err = oci.PushImageToRegistry(img, fmt.Sprintf("%s/%s:tag-does-not-matter", serverURL.Host, repoName))
 			require.NoError(t, err)
 			mf, err := img.Manifest()
 			require.NoError(t, err)
--- a/pkg/attestation/registry.go
+++ b/pkg/attestation/registry.go
@@ -0,0 +1,101 @@
+package attestation
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/docker/attest/pkg/oci"
+	"github.com/google/go-containerregistry/pkg/name"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
+	"github.com/google/go-containerregistry/pkg/v1/remote"
+)
+
+type RegistryResolver struct {
+	*oci.RegistryImageDetailsResolver
+	*Manifest
+}
+
+func NewRegistryResolver(src *oci.RegistryImageDetailsResolver) (*RegistryResolver, error) {
+	return &RegistryResolver{
+		RegistryImageDetailsResolver: src,
+	}, nil
+}
+
+func (r *RegistryResolver) Attestations(ctx context.Context, predicateType string) ([]*Envelope, error) {
+	if r.Manifest == nil {
+		attest, err := FetchManifest(ctx, r.Identifier, r.ImageSpec.Platform)
+		if err != nil {
+			return nil, err
+		}
+		r.Manifest = attest
+	}
+	return ExtractEnvelopes(r.Manifest, predicateType)
+}
+
+func attestationDigestForImage(ix *v1.IndexManifest, imageDigest string, attestType string) (string, error) {
+	for i := range ix.Manifests {
+		m := &ix.Manifests[i]
+		if v, ok := m.Annotations[DockerReferenceType]; ok && v == attestType {
+			if d, ok := m.Annotations[DockerReferenceDigest]; ok && d == imageDigest {
+				return m.Digest.String(), nil
+			}
+		}
+	}
+	return "", fmt.Errorf("no attestation found for image %s", imageDigest)
+}
+
+func FetchManifest(ctx context.Context, image string, platform *v1.Platform) (*Manifest, error) {
+	// we want to get to the image index, so ignoring platform for now
+	options := oci.WithOptions(ctx, nil)
+	ref, err := name.ParseReference(image)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse reference: %w", err)
+	}
+	index, err := remote.Index(ref, options...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get index: %w", err)
+	}
+	indexManifest, err := index.IndexManifest()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get index manifest: %w", err)
+	}
+	subjectDescriptor, err := oci.ImageDescriptor(indexManifest, platform)
+	if err != nil {
+		return nil, fmt.Errorf("failed to obtain image for platform: %w", err)
+	}
+
+	digest := subjectDescriptor.Digest.String()
+	ref, err = name.ParseReference(fmt.Sprintf("%s@%s", ref.Context().Name(), digest))
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse attestation reference: %w", err)
+	}
+
+	attestationDigest, err := attestationDigestForImage(indexManifest, digest, "attestation-manifest")
+	if err != nil {
+		return nil, fmt.Errorf("failed to obtain attestation for image: %w", err)
+	}
+	ref, err = name.ParseReference(fmt.Sprintf("%s@%s", ref.Context().Name(), attestationDigest))
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse attestation reference: %w", err)
+	}
+	remoteDescriptor, err := remote.Get(ref, options...)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get attestation: %w", err)
+	}
+	attestationImage, err := remoteDescriptor.Image()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get attestation image: %w", err)
+	}
+
+	layers, err := layersFromImage(attestationImage)
+	if err != nil {
+		return nil, fmt.Errorf("failed to get attestations from image: %w", err)
+	}
+	attest := &Manifest{
+		OriginalLayers:     layers,
+		OriginalDescriptor: &remoteDescriptor.Descriptor,
+		SubjectName:        image,
+		SubjectDescriptor:  subjectDescriptor,
+	}
+	return attest, nil
+}
--- a/pkg/attestation/registry_test.go
+++ b/pkg/attestation/registry_test.go
@@ -1,4 +1,4 @@
-package oci_test
+package attestation_test

 import (
 	"fmt"
@@ -10,7 +10,6 @@ import (
 	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/mirror"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
 	"github.com/google/go-containerregistry/pkg/registry"
@@ -26,7 +25,7 @@ func TestRegistry(t *testing.T) {
 	require.NoError(t, err)

 	opts := &attestation.SigningOptions{}
-	attIdx, err := oci.IndexFromPath(oci.UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	require.NoError(t, err)
 	signedManifests, err := attest.SignStatements(ctx, attIdx.Index, signer, opts)
 	require.NoError(t, err)
@@ -36,7 +35,7 @@ func TestRegistry(t *testing.T) {

 	indexName := fmt.Sprintf("%s/repo:root", u.Host)
 	require.NoError(t, err)
-	err = mirror.PushIndexToRegistry(signedIndex, indexName)
+	err = oci.PushIndexToRegistry(signedIndex, indexName)
 	require.NoError(t, err)

 	spec, err := oci.ParseImageSpec(indexName)
--- a/pkg/attestation/resolver.go
+++ b/pkg/attestation/resolver.go
@@ -0,0 +1,12 @@
+package attestation
+
+import (
+	"context"
+
+	"github.com/docker/attest/pkg/oci"
+)
+
+type Resolver interface {
+	oci.ImageDetailsResolver
+	Attestations(ctx context.Context, mediaType string) ([]*Envelope, error)
+}
--- a/pkg/attestation/sign_test.go
+++ b/pkg/attestation/sign_test.go
@@ -6,12 +6,19 @@ import (
 	"crypto/rand"
 	"encoding/json"
 	"fmt"
+	"net/http/httptest"
+	"net/url"
 	"testing"
 	"time"

 	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/signerverifier"
+	"github.com/google/go-containerregistry/pkg/registry"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
+	"github.com/google/go-containerregistry/pkg/v1/static"
+	"github.com/google/go-containerregistry/pkg/v1/types"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -149,3 +156,146 @@ func TestSignVerifyAttestation(t *testing.T) {
 		})
 	}
 }
+
+func TestAddSignedLayerAnnotations(t *testing.T) {
+	ctx, signer := test.Setup(t)
+	testCases := []struct {
+		name    string
+		replace bool
+	}{
+		{"replaced", true},
+		{"not replaced", false},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			data := []byte("signed")
+			testLayer := static.NewLayer(data, types.MediaType(intoto.PayloadType))
+			mediaType := types.OCIManifestSchema1
+			opts := &attestation.SigningOptions{}
+			originalLayer := &attestation.Layer{
+				Layer: testLayer,
+				Statement: &intoto.Statement{
+					StatementHeader: intoto.StatementHeader{
+						PredicateType: attestation.VSAPredicateType,
+					},
+				},
+				Annotations: map[string]string{"test": "test"},
+			}
+
+			manifest := &attestation.Manifest{
+				OriginalDescriptor: &v1.Descriptor{
+					MediaType: mediaType,
+				},
+				OriginalLayers: []*attestation.Layer{
+					originalLayer,
+				},
+				SubjectDescriptor: &v1.Descriptor{},
+			}
+			err := manifest.Add(ctx, signer, originalLayer.Statement, opts)
+			require.NoError(t, err)
+
+			newImg, err := manifest.BuildImage(attestation.WithReplacedLayers(tc.replace))
+			require.NoError(t, err)
+			mf, _ := newImg.RawManifest()
+			type Annotations struct {
+				Annotations map[string]string `json:"annotations"`
+			}
+			type Layers struct {
+				Layers []Annotations `json:"layers"`
+			}
+			l := &Layers{}
+			err = json.Unmarshal(mf, l)
+			require.NoError(t, err)
+			_, ok := l.Layers[0].Annotations["test"]
+			assert.Truef(t, ok, "missing annotations")
+		})
+	}
+}
+
+func TestSimpleStatementSigning(t *testing.T) {
+	ctx, signer := test.Setup(t)
+	empty := types.MediaType("application/vnd.oci.empty.v1+json")
+	testCases := []struct {
+		name    string
+		replace bool
+	}{
+		{"replaced", true},
+		{"not replaced", false},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			opts := &attestation.SigningOptions{}
+			statement := &intoto.Statement{
+				StatementHeader: intoto.StatementHeader{
+					PredicateType: attestation.VSAPredicateType,
+				},
+			}
+			statement2 := &intoto.Statement{
+				StatementHeader: intoto.StatementHeader{
+					PredicateType: attestation.VSAPredicateType,
+				},
+			}
+			digest, err := v1.NewHash("sha256:da8b190665956ea07890a0273e2a9c96bfe291662f08e2860e868eef69c34620")
+			require.NoError(t, err)
+			subject := &v1.Descriptor{
+				MediaType: "application/vnd.oci.image.manifest.v1+json",
+				Digest:    digest,
+			}
+			manifest, err := attestation.NewManifest(subject)
+			require.NoError(t, err)
+			err = manifest.Add(ctx, signer, statement, opts)
+			require.NoError(t, err)
+
+			err = manifest.Add(ctx, signer, statement2, opts)
+			require.NoError(t, err)
+
+			// fake that the manfifest was loaded from a real image
+			manifest.OriginalLayers = manifest.SignedLayers
+			envelopes, err := attestation.ExtractEnvelopes(manifest, attestation.VSAPredicateType)
+			require.NoError(t, err)
+			assert.Len(t, envelopes, 2)
+
+			newImg, err := manifest.BuildImage(attestation.WithReplacedLayers(tc.replace))
+			require.NoError(t, err)
+			layers, err := newImg.Layers()
+			require.NoError(t, err)
+			if tc.replace {
+				assert.Len(t, layers, 2)
+			} else {
+				assert.Len(t, layers, 4)
+			}
+
+			newImgs, err := manifest.BuildReferringArtifacts()
+			require.NoError(t, err)
+			assert.Len(t, newImgs, 2)
+			for _, img := range newImgs {
+				mf, err := img.Manifest()
+				require.NoError(t, err)
+				assert.Contains(t, mf.ArtifactType, "application/vnd.in-toto")
+				assert.Contains(t, mf.ArtifactType, "+dsse")
+				assert.Equal(t, subject.MediaType, mf.MediaType)
+				assert.Equal(t, empty, mf.Config.MediaType)
+				assert.Equal(t, int64(2), mf.Config.Size)
+				assert.Equal(t, "{}", string(mf.Config.Data))
+				layers, err := img.Layers()
+				require.NoError(t, err)
+				assert.Len(t, layers, 1)
+			}
+			server := httptest.NewServer(registry.New(registry.WithReferrersSupport(true)))
+			defer server.Close()
+
+			u, err := url.Parse(server.URL)
+			require.NoError(t, err)
+
+			indexName := fmt.Sprintf("%s/repo:root", u.Host)
+			output, err := oci.ParseImageSpecs(indexName)
+			require.NoError(t, err)
+			artifacts, err := manifest.BuildReferringArtifacts()
+			require.NoError(t, err)
+			err = oci.SaveImagesNoTag(artifacts, output)
+			require.NoError(t, err)
+		})
+	}
+}
--- a/pkg/attestation/types.go
+++ b/pkg/attestation/types.go
@@ -36,7 +36,7 @@ type Manifest struct {

 	// accumulated during signing
 	SignedLayers []*Layer
-	// details of subect image
+	// details of subject image
 	SubjectName       string
 	SubjectDescriptor *v1.Descriptor
 }
@@ -64,6 +64,12 @@ type Extension struct {
 	Ext  *DockerDSSEExtension `json:"ext"`
 }

+type AnnotatedStatement struct {
+	OCIDescriptor   *v1.Descriptor
+	InTotoStatement *intoto.Statement
+	Annotations     map[string]string
+}
+
 type DockerDSSEExtension struct {
 	TL *DockerTLExtension `json:"tl"`
 }
@@ -83,6 +89,12 @@ type SigningOptions struct {
 	SkipTL bool
 }

+type Options struct {
+	NoReferrers   bool
+	Attach        bool
+	ReferrersRepo string
+}
+
 func DSSEMediaType(predicateType string) (string, error) {
 	var predicateName string
 	switch predicateType {
--- a/pkg/attestation/vsa.go
+++ b/pkg/attestation/vsa.go
@@ -16,7 +16,7 @@ type VSAPredicate struct {
 	TimeVerified       string                `json:"timeVerified"`
 	ResourceURI        string                `json:"resourceUri"`
 	Policy             VSAPolicy             `json:"policy"`
-	InputAttestations  []VSAInputAttestation `json:"inputAttestations"`
+	InputAttestations  []VSAInputAttestation `json:"inputAttestations,omitempty"`
 	VerificationResult string                `json:"verificationResult"`
 	VerifiedLevels     []string              `json:"verifiedLevels"`
 }
@@ -26,7 +26,9 @@ type VSAVerifier struct {
 }

 type VSAPolicy struct {
-	URI string `json:"uri"`
+	URI              string            `json:"uri,omitempty"`
+	Digest           map[string]string `json:"digest"`
+	DownloadLocation string            `json:"downloadLocation,omitempty"`
 }

 type VSAInputAttestation struct {
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -36,13 +36,13 @@ func LoadTUFMappings(tufClient tuf.Downloader, localTargetsDir string) (*PolicyM
 		return nil, fmt.Errorf("tuf client not set")
 	}
 	filename := MappingFilename
-	_, fileContents, err := tufClient.DownloadTarget(filename, filepath.Join(localTargetsDir, filename))
+	file, err := tufClient.DownloadTarget(filename, filepath.Join(localTargetsDir, filename))
 	if err != nil {
 		return nil, fmt.Errorf("failed to download policy mapping file %s: %w", filename, err)
 	}
 	mappings := &policyMappingsFile{}

-	err = yaml.Unmarshal(fileContents, mappings)
+	err = yaml.Unmarshal(file.Data, mappings)
 	if err != nil {
 		return nil, fmt.Errorf("failed to unmarshal policy mapping file %s: %w", filename, err)
 	}
--- a/pkg/mirror/README.md
+++ b/pkg/mirror/README.md
@@ -0,0 +1,2 @@
+## mirror
+This package contains components to mirror TUF metadata and targets to OCI.
--- a/pkg/mirror/example_mirror_test.go
+++ b/pkg/mirror/example_mirror_test.go
@@ -8,6 +8,7 @@ import (

 	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/pkg/mirror"
+	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/tuf"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 )
@@ -80,7 +81,7 @@ func ExampleNewTUFMirror() {
 func mirrorToRegistry(o *TufMirrorOutput) error {
 	// push metadata to registry
 	metadataRepo := "registry-1.docker.io/docker/tuf-metadata:latest"
-	err := mirror.PushImageToRegistry(o.metadata, metadataRepo)
+	err := oci.PushImageToRegistry(o.metadata, metadataRepo)
 	if err != nil {
 		return err
 	}
@@ -91,7 +92,7 @@ func mirrorToRegistry(o *TufMirrorOutput) error {
 			return fmt.Errorf("failed to get repo without tag: %s", metadataRepo)
 		}
 		imageName := fmt.Sprintf("%s:%s", repo, metadata.Tag)
-		err = mirror.PushImageToRegistry(metadata.Image, imageName)
+		err = oci.PushImageToRegistry(metadata.Image, imageName)
 		if err != nil {
 			return err
 		}
@@ -101,7 +102,7 @@ func mirrorToRegistry(o *TufMirrorOutput) error {
 	targetsRepo := "registry-1.docker.io/docker/tuf-targets"
 	for _, target := range o.targets {
 		imageName := fmt.Sprintf("%s:%s", targetsRepo, target.Tag)
-		err = mirror.PushImageToRegistry(target.Image, imageName)
+		err = oci.PushImageToRegistry(target.Image, imageName)
 		if err != nil {
 			return err
 		}
@@ -109,7 +110,7 @@ func mirrorToRegistry(o *TufMirrorOutput) error {
 	// push delegated targets to registry
 	for _, target := range o.delegatedTargets {
 		imageName := fmt.Sprintf("%s:%s", targetsRepo, target.Tag)
-		err = mirror.PushIndexToRegistry(target.Index, imageName)
+		err = oci.PushIndexToRegistry(target.Index, imageName)
 		if err != nil {
 			return err
 		}
@@ -119,14 +120,14 @@ func mirrorToRegistry(o *TufMirrorOutput) error {

 func mirrorToLocal(o *TufMirrorOutput, outputPath string) error {
 	// output metadata to local directory
-	err := mirror.SaveImageAsOCILayout(o.metadata, outputPath)
+	err := oci.SaveImageAsOCILayout(o.metadata, outputPath)
 	if err != nil {
 		return err
 	}
 	// output delegated metadata to local directory
 	for _, metadata := range o.delegatedMetadata {
 		path := filepath.Join(outputPath, metadata.Tag)
-		err = mirror.SaveImageAsOCILayout(metadata.Image, path)
+		err = oci.SaveImageAsOCILayout(metadata.Image, path)
 		if err != nil {
 			return err
 		}
@@ -135,7 +136,7 @@ func mirrorToLocal(o *TufMirrorOutput, outputPath string) error {
 	// output top-level targets to local directory
 	for _, target := range o.targets {
 		path := filepath.Join(outputPath, target.Tag)
-		err = mirror.SaveImageAsOCILayout(target.Image, path)
+		err = oci.SaveImageAsOCILayout(target.Image, path)
 		if err != nil {
 			return err
 		}
@@ -143,7 +144,7 @@ func mirrorToLocal(o *TufMirrorOutput, outputPath string) error {
 	// output delegated targets to local directory
 	for _, target := range o.delegatedTargets {
 		path := filepath.Join(outputPath, target.Tag)
-		err = mirror.SaveIndexAsOCILayout(target.Index, path)
+		err = oci.SaveIndexAsOCILayout(target.Index, path)
 		if err != nil {
 			return err
 		}
--- a/pkg/mirror/metadata.go
+++ b/pkg/mirror/metadata.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"strconv"

+	"github.com/docker/attest/pkg/oci"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/empty"
 	"github.com/google/go-containerregistry/pkg/v1/mutate"
@@ -17,7 +18,7 @@ import (
 // -----------------

 // GetMetadataManifest returns an image with TUF root metadata as layers.
-func (m *TUFMirror) GetMetadataManifest(metadataURL string) (v1.Image, error) {
+func (m *TUFMirror) GetMetadataManifest(metadataURL string) (*oci.EmptyConfigImage, error) {
 	metadata, err := m.getMetadataMirror(metadataURL)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get metadata: %w", err)
@@ -26,7 +27,7 @@ func (m *TUFMirror) GetMetadataManifest(metadataURL string) (v1.Image, error) {
 	if err != nil {
 		return nil, fmt.Errorf("failed to build metadata manifest: %w", err)
 	}
-	return manifest, nil
+	return &oci.EmptyConfigImage{Image: manifest}, nil
 }

 // getMetadataMirror returns a TufMetadata struct with TUF metadata as map of file names to bytes.
@@ -183,7 +184,7 @@ func (m *TUFMirror) buildDelegatedMetadataManifests(delegated []DelegatedTargetM
 		if err != nil {
 			return nil, fmt.Errorf("failed to append delegated targets layer to image: %w", err)
 		}
-		manifests = append(manifests, &Image{Image: img, Tag: role.Name})
+		manifests = append(manifests, &Image{Image: &oci.EmptyConfigImage{Image: img}, Tag: role.Name})
 	}
 	return manifests, nil
 }
--- a/pkg/mirror/metadata_test.go
+++ b/pkg/mirror/metadata_test.go
@@ -16,15 +16,20 @@ import (
 	"github.com/theupdateframework/go-tuf/v2/metadata"
 )

+const (
+	metadataPath = "/metadata"
+	targetsPath  = "/targets"
+)
+
 func TestGetTufMetadataMirror(t *testing.T) {
 	server := httptest.NewServer(http.FileServer(http.Dir(filepath.Join("..", "..", "test", "testdata", "tuf", "test-repo"))))
 	defer server.Close()

 	path := test.CreateTempDir(t, "", "tuf_temp")
-	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+"/metadata", server.URL+"/targets", tuf.NewMockVersionChecker())
+	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)

-	tufMetadata, err := m.getMetadataMirror(server.URL + "/metadata")
+	tufMetadata, err := m.getMetadataMirror(server.URL + metadataPath)
 	assert.NoError(t, err)

 	// check that all roles are not empty
@@ -39,10 +44,10 @@ func TestGetMetadataManifest(t *testing.T) {
 	defer server.Close()

 	path := test.CreateTempDir(t, "", "tuf_temp")
-	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+"/metadata", server.URL+"/targets", tuf.NewMockVersionChecker())
+	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)

-	img, err := m.GetMetadataManifest(server.URL + "/metadata")
+	img, err := m.GetMetadataManifest(server.URL + metadataPath)
 	assert.NoError(t, err)
 	assert.NotNil(t, img)

@@ -78,7 +83,7 @@ func TestGetDelegatedMetadataMirrors(t *testing.T) {
 	defer server.Close()

 	path := test.CreateTempDir(t, "", "tuf_temp")
-	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+"/metadata", server.URL+"/targets", tuf.NewMockVersionChecker())
+	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)

 	delegations, err := m.GetDelegatedMetadataMirrors()
--- a/pkg/mirror/mirror.go
+++ b/pkg/mirror/mirror.go
@@ -2,18 +2,9 @@ package mirror

 import (
 	"fmt"
-	"os"

 	"github.com/docker/attest/internal/embed"
-	"github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/tuf"
-	"github.com/google/go-containerregistry/pkg/name"
-	v1 "github.com/google/go-containerregistry/pkg/v1"
-	"github.com/google/go-containerregistry/pkg/v1/empty"
-	"github.com/google/go-containerregistry/pkg/v1/layout"
-	"github.com/google/go-containerregistry/pkg/v1/mutate"
-	"github.com/google/go-containerregistry/pkg/v1/remote"
 )

 func NewTUFMirror(root []byte, tufPath, metadataURL, targetsURL string, versionChecker tuf.VersionChecker) (*TUFMirror, error) {
@@ -26,132 +17,3 @@ func NewTUFMirror(root []byte, tufPath, metadataURL, targetsURL string, versionC
 	}
 	return &TUFMirror{TUFClient: tufClient, tufPath: tufPath, metadataURL: metadataURL, targetsURL: targetsURL}, nil
 }
-
-func PushImageToRegistry(image v1.Image, imageName string) error {
-	ref, err := name.ParseReference(imageName)
-	if err != nil {
-		return fmt.Errorf("Failed to parse image name '%s': %w", imageName, err)
-	}
-
-	// Push the image to the registry
-	return remote.Write(ref, image, oci.MultiKeychainOption())
-}
-
-func PushIndexToRegistry(index v1.ImageIndex, imageName string) error {
-	// Parse the index name
-	ref, err := name.ParseReference(imageName)
-	if err != nil {
-		return fmt.Errorf("Failed to parse image name: %w", err)
-	}
-
-	// Push the index to the registry
-	return remote.WriteIndex(ref, index, oci.MultiKeychainOption())
-}
-
-func SaveImageAsOCILayout(image v1.Image, path string) error {
-	// Save the image to the local filesystem
-	err := os.MkdirAll(path, os.ModePerm)
-	if err != nil {
-		return fmt.Errorf("failed to create directory: %w", err)
-	}
-	index := empty.Index
-	l, err := layout.Write(path, index)
-	if err != nil {
-		return fmt.Errorf("failed to create index: %w", err)
-	}
-	return l.AppendImage(image)
-}
-
-func SaveIndexAsOCILayout(image v1.ImageIndex, path string) error {
-	// Save the index to the local filesystem
-	err := os.MkdirAll(path, os.ModePerm)
-	if err != nil {
-		return fmt.Errorf("failed to create directory: %w", err)
-	}
-
-	_, err = layout.Write(path, image)
-	if err != nil {
-		return fmt.Errorf("failed to create index: %w", err)
-	}
-	return nil
-}
-
-func SaveIndex(outputs []*oci.ImageSpec, index v1.ImageIndex, indexName string) error {
-	// split output by comma and write or push each one
-	for _, output := range outputs {
-		if output.Type == oci.OCI {
-			idx := v1.ImageIndex(empty.Index)
-			idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
-				Add: index,
-				Descriptor: v1.Descriptor{
-					Annotations: map[string]string{
-						oci.OCIReferenceTarget: indexName,
-					},
-				},
-			})
-			err := SaveIndexAsOCILayout(idx, output.Identifier)
-			if err != nil {
-				return fmt.Errorf("failed to write signed image: %w", err)
-			}
-		} else {
-			err := PushIndexToRegistry(index, output.Identifier)
-			if err != nil {
-				return fmt.Errorf("failed to push signed image: %w", err)
-			}
-		}
-	}
-	return nil
-}
-
-func SaveImage(output *oci.ImageSpec, image v1.Image, imageName string) error {
-	if output.Type == oci.OCI {
-		idx := v1.ImageIndex(empty.Index)
-		idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
-			Add: image,
-			Descriptor: v1.Descriptor{
-				Annotations: map[string]string{
-					oci.OCIReferenceTarget: imageName,
-				},
-			},
-		})
-		err := SaveIndexAsOCILayout(idx, output.Identifier)
-		if err != nil {
-			return fmt.Errorf("failed to write signed image: %w", err)
-		}
-	} else {
-		err := PushImageToRegistry(image, output.Identifier)
-		if err != nil {
-			return fmt.Errorf("failed to push signed image: %w", err)
-		}
-	}
-	return nil
-}
-
-func SaveReferrers(manifest *attestation.Manifest, outputs []*oci.ImageSpec) error {
-	for _, output := range outputs {
-		if output.Type == oci.OCI {
-			continue
-		}
-		// so that we use the same tag each time to reduce number of tags (tags aren't needed for referrers but we must push one)
-		attOut, err := oci.ReplaceTagInSpec(output, manifest.SubjectDescriptor.Digest)
-		if err != nil {
-			return err
-		}
-		// otherwise we end up with the detected platform, though I'm not sure it matters
-		attOut.Platform = &v1.Platform{
-			OS:           "unknown",
-			Architecture: "unknown",
-		}
-		images, err := manifest.BuildReferringArtifacts()
-		if err != nil {
-			return fmt.Errorf("failed to build image: %w", err)
-		}
-		for _, image := range images {
-			err = SaveImage(attOut, image, "")
-		}
-		if err != nil {
-			return fmt.Errorf("failed to push image: %w", err)
-		}
-	}
-	return nil
-}
--- a/pkg/mirror/targets.go
+++ b/pkg/mirror/targets.go
@@ -5,6 +5,7 @@ import (
 	"path/filepath"
 	"strings"

+	"github.com/docker/attest/pkg/oci"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/empty"
 	"github.com/google/go-containerregistry/pkg/v1/mutate"
@@ -22,7 +23,7 @@ func (m *TUFMirror) GetTUFTargetMirrors() ([]*Image, error) {
 	targets := md.Targets[metadata.TARGETS].Signed.Targets
 	for _, t := range targets {
 		// download target file
-		_, data, err := m.TUFClient.DownloadTarget(t.Path, filepath.Join(m.tufPath, "download"))
+		file, err := m.TUFClient.DownloadTarget(t.Path, filepath.Join(m.tufPath, "download"))
 		if err != nil {
 			return nil, fmt.Errorf("failed to download target %s: %w", t.Path, err)
 		}
@@ -37,12 +38,12 @@ func (m *TUFMirror) GetTUFTargetMirrors() ([]*Image, error) {
 		}
 		name := hash.String() + "." + t.Path
 		ann := map[string]string{tufFileAnnotation: name}
-		layer := mutate.Addendum{Layer: static.NewLayer(data, tufTargetMediaType), Annotations: ann}
+		layer := mutate.Addendum{Layer: static.NewLayer(file.Data, tufTargetMediaType), Annotations: ann}
 		img, err = mutate.Append(img, layer)
 		if err != nil {
 			return nil, fmt.Errorf("failed to append role layer to image: %w", err)
 		}
-		targetMirrors = append(targetMirrors, &Image{Image: img, Tag: name})
+		targetMirrors = append(targetMirrors, &Image{Image: &oci.EmptyConfigImage{Image: img}, Tag: name})
 	}
 	return targetMirrors, nil
 }
@@ -68,7 +69,7 @@ func (m *TUFMirror) GetDelegatedTargetMirrors() ([]*Index, error) {
 		// for each target file, create an image with the target file as a layer
 		for _, target := range roleMeta.Signed.Targets {
 			// download target file
-			_, data, err := m.TUFClient.DownloadTarget(target.Path, filepath.Join(m.tufPath, "download"))
+			file, err := m.TUFClient.DownloadTarget(target.Path, filepath.Join(m.tufPath, "download"))
 			if err != nil {
 				return nil, fmt.Errorf("failed to download target %s: %w", target.Path, err)
 			}
@@ -88,14 +89,15 @@ func (m *TUFMirror) GetDelegatedTargetMirrors() ([]*Index, error) {
 			}
 			name := hash.String() + "." + filename
 			ann := map[string]string{tufFileAnnotation: name}
-			layer := mutate.Addendum{Layer: static.NewLayer(data, tufTargetMediaType), Annotations: ann}
+			layer := mutate.Addendum{Layer: static.NewLayer(file.Data, tufTargetMediaType), Annotations: ann}
 			img, err = mutate.Append(img, layer)
 			if err != nil {
 				return nil, fmt.Errorf("failed to append role layer to image: %w", err)
 			}
+			emptyConfigImage := &oci.EmptyConfigImage{Image: img}
 			// append image to index with annotation
 			index = mutate.AppendManifests(index, mutate.IndexAddendum{
-				Add: img,
+				Add: emptyConfigImage,
 				Descriptor: v1.Descriptor{
 					Annotations: map[string]string{
 						tufFileAnnotation: fmt.Sprintf("%s/%s", subdir, name),
--- a/pkg/mirror/targets_test.go
+++ b/pkg/mirror/targets_test.go
@@ -27,7 +27,7 @@ func TestGetTufTargetsMirror(t *testing.T) {
 	defer server.Close()

 	path := test.CreateTempDir(t, "", "tuf_temp")
-	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+"/metadata", server.URL+"/targets", tuf.NewMockVersionChecker())
+	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)

 	targets, err := m.GetTUFTargetMirrors()
@@ -61,7 +61,7 @@ func TestTargetDelegationMetadata(t *testing.T) {
 	defer server.Close()

 	path := test.CreateTempDir(t, "", "tuf_temp")
-	tm, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+"/metadata", server.URL+"/targets", tuf.NewMockVersionChecker())
+	tm, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)

 	targets, err := tm.TUFClient.LoadDelegatedTargets("test-role", "targets")
@@ -74,7 +74,7 @@ func TestGetDelegatedTargetMirrors(t *testing.T) {
 	defer server.Close()

 	path := test.CreateTempDir(t, "", "tuf_temp")
-	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+"/metadata", server.URL+"/targets", tuf.NewMockVersionChecker())
+	m, err := NewTUFMirror(embed.RootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)

 	mirrors, err := m.GetDelegatedTargetMirrors()
--- a/pkg/mirror/types.go
+++ b/pkg/mirror/types.go
@@ -1,6 +1,7 @@
 package mirror

 import (
+	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/tuf"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/theupdateframework/go-tuf/v2/metadata"
@@ -32,7 +33,7 @@ type DelegatedTargetMetadata struct {
 }

 type Image struct {
-	Image v1.Image
+	Image *oci.EmptyConfigImage
 	Tag   string
 }

--- a/pkg/oci/README.md
+++ b/pkg/oci/README.md
@@ -0,0 +1,2 @@
+## oci
+This package is for generic OCI components. For attestation specific components see the `attestation` package.
--- a/pkg/mirror/authn_test.go
+++ b/pkg/mirror/authn_test.go
@@ -1,20 +1,17 @@
 //go:build e2e

-package mirror_test
+package oci_test

 import (
-	"path/filepath"
 	"testing"

-	"github.com/docker/attest/pkg/mirror"
+	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/stretchr/testify/require"
 )

 func TestRegistryAuth(t *testing.T) {
-	UnsignedTestImage := filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
-
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	require.NoError(t, err)
 	// test cases for ecr, gcr and dockerhub
 	testCases := []struct {
@@ -25,7 +22,7 @@ func TestRegistryAuth(t *testing.T) {
 	}
 	for _, tc := range testCases {
 		t.Run(tc.Image, func(t *testing.T) {
-			err := mirror.PushIndexToRegistry(attIdx.Index, tc.Image)
+			err := oci.PushIndexToRegistry(attIdx.Index, tc.Image)
 			require.NoError(t, err)
 			_, err = oci.IndexFromRemote(tc.Image)
 			require.NoError(t, err)
--- a/pkg/oci/oci.go
+++ b/pkg/oci/oci.go
@@ -2,14 +2,11 @@ package oci

 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"strings"

 	"github.com/containerd/platforms"
 	"github.com/distribution/reference"
-	"github.com/docker/attest/pkg/attestation"
-	att "github.com/docker/attest/pkg/attestation"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 	"github.com/in-toto/in-toto-golang/in_toto/slsa_provenance/common"
@@ -45,36 +42,7 @@ func WithOptions(ctx context.Context, platform *v1.Platform) []remote.Option {
 	return options
 }

-func ExtractEnvelopes(manifest *attestation.Manifest, predicateType string) ([]*att.Envelope, error) {
-	var envs []*att.Envelope
-	dsseMediaType, err := attestation.DSSEMediaType(predicateType)
-	if err != nil {
-		return nil, fmt.Errorf("failed to get DSSE media type for predicate '%s': %w", predicateType, err)
-	}
-	for _, attestationLayer := range manifest.OriginalLayers {
-		mt, err := attestationLayer.Layer.MediaType()
-		if err != nil {
-			return nil, fmt.Errorf("failed to get layer media type: %w", err)
-		}
-		if string(mt) == dsseMediaType {
-			reader, err := attestationLayer.Layer.Uncompressed()
-			if err != nil {
-				return nil, fmt.Errorf("failed to get layer contents: %w", err)
-			}
-			defer reader.Close()
-			env := new(att.Envelope)
-			err = json.NewDecoder(reader).Decode(&env)
-			if err != nil {
-				return nil, fmt.Errorf("failed to decode envelope: %w", err)
-			}
-			envs = append(envs, env)
-		}
-	}
-
-	return envs, nil
-}
-
-func imageDescriptor(ix *v1.IndexManifest, platform *v1.Platform) (*v1.Descriptor, error) {
+func ImageDescriptor(ix *v1.IndexManifest, platform *v1.Platform) (*v1.Descriptor, error) {
 	for i := range ix.Manifests {
 		m := &ix.Manifests[i]
 		if (m.MediaType == ocispec.MediaTypeImageManifest || m.MediaType == "application/vnd.docker.distribution.manifest.v2+json") && m.Platform.Equals(*platform) {
@@ -84,18 +52,6 @@ func imageDescriptor(ix *v1.IndexManifest, platform *v1.Platform) (*v1.Descripto
 	return nil, fmt.Errorf("no image found for platform %v", platform)
 }

-func attestationDigestForDigest(ix *v1.IndexManifest, imageDigest string, attestType string) (string, error) {
-	for i := range ix.Manifests {
-		m := &ix.Manifests[i]
-		if v, ok := m.Annotations[att.DockerReferenceType]; ok && v == attestType {
-			if d, ok := m.Annotations[att.DockerReferenceDigest]; ok && d == imageDigest {
-				return m.Digest.String(), nil
-			}
-		}
-	}
-	return "", fmt.Errorf("no attestation found for image %s", imageDigest)
-}
-
 func RefToPURL(ref string, platform *v1.Platform) (string, bool, error) {
 	var isCanonical bool
 	named, err := reference.ParseNormalizedNamed(ref)
@@ -150,7 +106,7 @@ func SplitDigest(digest string) (common.DigestSet, error) {
 }

 func ReplaceTagInSpec(src *ImageSpec, digest v1.Hash) (*ImageSpec, error) {
-	newName, err := replaceTag(src.Identifier, digest)
+	newName, err := ReplaceTag(src.Identifier, digest)
 	if err != nil {
 		return nil, fmt.Errorf("failed to parse repo name: %w", err)
 	}
@@ -162,7 +118,7 @@ func ReplaceTagInSpec(src *ImageSpec, digest v1.Hash) (*ImageSpec, error) {
 }

 // so that the index tag is replaced with a tag unique to the image digest and doesn't overwrite it.
-func replaceTag(image string, digest v1.Hash) (string, error) {
+func ReplaceTag(image string, digest v1.Hash) (string, error) {
 	if strings.HasPrefix(image, LocalPrefix) {
 		return image, nil
 	}
@@ -172,3 +128,26 @@ func replaceTag(image string, digest v1.Hash) (string, error) {
 	}
 	return fmt.Sprintf("%s:%s-%s.att", notag, digest.Algorithm, digest.Hex), nil
 }
+
+func ReplaceDigestInSpec(src *ImageSpec, digest v1.Hash) (*ImageSpec, error) {
+	newName, err := replaceDigest(src.Identifier, digest)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse repo name: %w", err)
+	}
+	return &ImageSpec{
+		Identifier: newName,
+		Type:       src.Type,
+		Platform:   src.Platform,
+	}, nil
+}
+
+func replaceDigest(image string, digest v1.Hash) (string, error) {
+	if strings.HasPrefix(image, LocalPrefix) {
+		return image, nil
+	}
+	notag, err := WithoutTag(image)
+	if err != nil {
+		return "", nil
+	}
+	return fmt.Sprintf("%s@%s:%s", notag, digest.Algorithm, digest.Hex), nil
+}
--- a/pkg/oci/oci_test.go
+++ b/pkg/oci/oci_test.go
@@ -1,9 +1,10 @@
-package oci
+package oci_test

 import (
-	"path/filepath"
 	"testing"

+	"github.com/docker/attest/internal/test"
+	"github.com/docker/attest/pkg/oci"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/layout"
 	"github.com/stretchr/testify/assert"
@@ -11,54 +12,52 @@ import (
 )

 func TestRefToPurl(t *testing.T) {
-	arm, err := ParsePlatform("arm64/linux")
+	arm, err := oci.ParsePlatform("arm64/linux")
 	require.NoError(t, err)
-	purl, canonical, err := RefToPURL("alpine", arm)
+	purl, canonical, err := oci.RefToPURL("alpine", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@latest?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("alpine:123", arm)
+	purl, canonical, err = oci.RefToPURL("alpine:123", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("google/alpine:123", arm)
+	purl, canonical, err = oci.RefToPURL("google/alpine:123", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/google/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("library/alpine:123", arm)
+	purl, canonical, err = oci.RefToPURL("library/alpine:123", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("docker.io/library/alpine:123", arm)
+	purl, canonical, err = oci.RefToPURL("docker.io/library/alpine:123", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("localhost:5001/library/alpine:123", arm)
+	purl, canonical, err = oci.RefToPURL("localhost:5001/library/alpine:123", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/localhost%3A5001/library/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("localhost:5001/alpine:123", arm)
+	purl, canonical, err = oci.RefToPURL("localhost:5001/alpine:123", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/localhost%3A5001/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)

-	purl, canonical, err = RefToPURL("localhost:5001/alpine@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b", arm)
+	purl, canonical, err = oci.RefToPURL("localhost:5001/alpine@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b", arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/localhost%3A5001/alpine?digest=sha256%3Ac5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b&platform=arm64%2Flinux", purl)
 	assert.True(t, canonical)
 }

-var UnsignedTestImage = filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
-
 // Test fix for https://github.com/docker/secure-artifacts-team-issues/issues/202
 func TestImageDigestForPlatform(t *testing.T) {
-	idx, err := layout.ImageIndexFromPath(UnsignedTestImage)
+	idx, err := layout.ImageIndexFromPath(test.UnsignedTestImage)
 	assert.NoError(t, err)

 	idxm, err := idx.IndexManifest()
@@ -72,16 +71,16 @@ func TestImageDigestForPlatform(t *testing.T) {
 	mfs2, err := mfs.IndexManifest()
 	assert.NoError(t, err)

-	p, err := ParsePlatform("linux/amd64")
+	p, err := oci.ParsePlatform("linux/amd64")
 	assert.NoError(t, err)
-	desc, err := imageDescriptor(mfs2, p)
+	desc, err := oci.ImageDescriptor(mfs2, p)
 	assert.NoError(t, err)
 	digest := desc.Digest.String()
 	assert.Equal(t, "sha256:da8b190665956ea07890a0273e2a9c96bfe291662f08e2860e868eef69c34620", digest)

-	p, err = ParsePlatform("linux/arm64")
+	p, err = oci.ParsePlatform("linux/arm64")
 	assert.NoError(t, err)
-	desc, err = imageDescriptor(mfs2, p)
+	desc, err = oci.ImageDescriptor(mfs2, p)
 	assert.NoError(t, err)
 	digest = desc.Digest.String()
 	assert.Equal(t, "sha256:7a76cec943853f9f7105b1976afa1bf7cd5bb6afc4e9d5852dd8da7cf81ae86e", digest)
@@ -95,14 +94,14 @@ func TestWithoutTag(t *testing.T) {
 		{name: "image:tag", expected: "index.docker.io/library/image"},
 		{name: "image", expected: "index.docker.io/library/image"},
 		{name: "image:sha256-digest.att", expected: "index.docker.io/library/image"},
-		{name: "docker://image:tag", expected: "docker://index.docker.io/library/image"},
+		{name: oci.RegistryPrefix + "image:tag", expected: oci.RegistryPrefix + "index.docker.io/library/image"},
 		{name: "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: "index.docker.io/library/image"},
-		{name: "docker://image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: "docker://index.docker.io/library/image"},
-		{name: "docker://127.0.0.1:36555/repo:latest", expected: "docker://127.0.0.1:36555/repo"},
+		{name: oci.RegistryPrefix + "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: oci.RegistryPrefix + "index.docker.io/library/image"},
+		{name: oci.RegistryPrefix + "127.0.0.1:36555/repo:latest", expected: oci.RegistryPrefix + "127.0.0.1:36555/repo"},
 	}
 	for _, c := range tc {
 		t.Run(c.name, func(t *testing.T) {
-			notag, _ := WithoutTag(c.name)
+			notag, _ := oci.WithoutTag(c.name)
 			assert.Equal(t, c.expected, notag)
 		})
 	}
@@ -116,11 +115,11 @@ func TestReplaceTag(t *testing.T) {
 		{name: "image:tag", expected: "index.docker.io/library/image:sha256-digest.att"},
 		{name: "image", expected: "index.docker.io/library/image:sha256-digest.att"},
 		{name: "image:sha256-digest.att", expected: "index.docker.io/library/image:sha256-digest.att"},
-		{name: "docker://image:tag", expected: "docker://index.docker.io/library/image:sha256-digest.att"},
+		{name: oci.RegistryPrefix + "image:tag", expected: oci.RegistryPrefix + "index.docker.io/library/image:sha256-digest.att"},
 		{name: "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: "index.docker.io/library/image:sha256-digest.att"},
-		{name: "oci://foobar", expected: "oci://foobar"},
-		{name: "docker://image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: "docker://index.docker.io/library/image:sha256-digest.att"},
-		{name: "docker://127.0.0.1:36555/repo:latest", expected: "docker://127.0.0.1:36555/repo:sha256-digest.att"},
+		{name: oci.LocalPrefix + "foobar", expected: oci.LocalPrefix + "foobar"},
+		{name: oci.RegistryPrefix + "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: oci.RegistryPrefix + "index.docker.io/library/image:sha256-digest.att"},
+		{name: oci.RegistryPrefix + "127.0.0.1:36555/repo:latest", expected: oci.RegistryPrefix + "127.0.0.1:36555/repo:sha256-digest.att"},
 	}

 	digest := v1.Hash{
@@ -129,7 +128,7 @@ func TestReplaceTag(t *testing.T) {
 	}
 	for _, c := range tc {
 		t.Run(c.name, func(t *testing.T) {
-			replaced, err := replaceTag(c.name, digest)
+			replaced, err := oci.ReplaceTag(c.name, digest)
 			require.NoError(t, err)
 			assert.Equal(t, c.expected, replaced)
 		})
--- a/pkg/oci/output.go
+++ b/pkg/oci/output.go
@@ -0,0 +1,144 @@
+package oci
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/google/go-containerregistry/pkg/name"
+	v1 "github.com/google/go-containerregistry/pkg/v1"
+	"github.com/google/go-containerregistry/pkg/v1/empty"
+	"github.com/google/go-containerregistry/pkg/v1/layout"
+	"github.com/google/go-containerregistry/pkg/v1/mutate"
+	"github.com/google/go-containerregistry/pkg/v1/remote"
+)
+
+// PushImageToRegistry pushes an image to the registry with the specified name.
+func PushImageToRegistry(image v1.Image, imageName string) error {
+	ref, err := name.ParseReference(imageName)
+	if err != nil {
+		return fmt.Errorf("Failed to parse image name '%s': %w", imageName, err)
+	}
+
+	// Push the image to the registry
+	return remote.Write(ref, image, MultiKeychainOption())
+}
+
+// PushIndexToRegistry pushes an index to the registry with the specified name.
+func PushIndexToRegistry(index v1.ImageIndex, imageName string) error {
+	// Parse the index name
+	ref, err := name.ParseReference(imageName)
+	if err != nil {
+		return fmt.Errorf("Failed to parse image name: %w", err)
+	}
+
+	// Push the index to the registry
+	return remote.WriteIndex(ref, index, MultiKeychainOption())
+}
+
+// SaveIndexAsOCILayout saves an image as an OCI layout to the specified path.
+func SaveImageAsOCILayout(image v1.Image, path string) error {
+	// Save the image to the local filesystem
+	err := os.MkdirAll(path, os.ModePerm)
+	if err != nil {
+		return fmt.Errorf("failed to create directory: %w", err)
+	}
+	index := empty.Index
+	l, err := layout.Write(path, index)
+	if err != nil {
+		return fmt.Errorf("failed to create index: %w", err)
+	}
+	return l.AppendImage(image)
+}
+
+// SaveIndexAsOCILayout saves an index as an OCI layout to the specified path.
+func SaveIndexAsOCILayout(image v1.ImageIndex, path string) error {
+	// Save the index to the local filesystem
+	err := os.MkdirAll(path, os.ModePerm)
+	if err != nil {
+		return fmt.Errorf("failed to create directory: %w", err)
+	}
+
+	_, err = layout.Write(path, image)
+	if err != nil {
+		return fmt.Errorf("failed to create index: %w", err)
+	}
+	return nil
+}
+
+// SaveIndex saves an index to the specified outputs.
+func SaveIndex(outputs []*ImageSpec, index v1.ImageIndex, indexName string) error {
+	// split output by comma and write or push each one
+	for _, output := range outputs {
+		if output.Type == OCI {
+			idx := v1.ImageIndex(empty.Index)
+			idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
+				Add: index,
+				Descriptor: v1.Descriptor{
+					Annotations: map[string]string{
+						OCIReferenceTarget: indexName,
+					},
+				},
+			})
+			err := SaveIndexAsOCILayout(idx, output.Identifier)
+			if err != nil {
+				return fmt.Errorf("failed to write signed image: %w", err)
+			}
+		} else {
+			err := PushIndexToRegistry(index, output.Identifier)
+			if err != nil {
+				return fmt.Errorf("failed to push signed image: %w", err)
+			}
+		}
+	}
+	return nil
+}
+
+// SaveImage saves an image to the specified output.
+func SaveImage(output *ImageSpec, image v1.Image, imageName string) error {
+	if output.Type == OCI {
+		idx := v1.ImageIndex(empty.Index)
+		idx = mutate.AppendManifests(idx, mutate.IndexAddendum{
+			Add: image,
+			Descriptor: v1.Descriptor{
+				Annotations: map[string]string{
+					OCIReferenceTarget: imageName,
+				},
+			},
+		})
+		err := SaveIndexAsOCILayout(idx, output.Identifier)
+		if err != nil {
+			return fmt.Errorf("failed to write signed image: %w", err)
+		}
+	} else {
+		err := PushImageToRegistry(image, output.Identifier)
+		if err != nil {
+			return fmt.Errorf("failed to push signed image: %w", err)
+		}
+	}
+	return nil
+}
+
+// SaveImagesNoTag saves a list of images by digest to the specified outputs.
+func SaveImagesNoTag(images []v1.Image, outputs []*ImageSpec) error {
+	for _, output := range outputs {
+		// OCI layout output not supported
+		if output.Type == OCI {
+			continue
+		}
+		for _, image := range images {
+			digest, err := image.Digest()
+			if err != nil {
+				return fmt.Errorf("failed to get image digest: %w", err)
+			}
+			spec, err := ReplaceDigestInSpec(output, digest)
+			if err != nil {
+				return fmt.Errorf("failed to create image spec: %w", err)
+			}
+			err = PushImageToRegistry(image, spec.Identifier)
+			if err != nil {
+				return fmt.Errorf("failed to push image: %w", err)
+			}
+		}
+	}
+	return nil
+}
--- a/pkg/mirror/mirror_test.go
+++ b/pkg/mirror/mirror_test.go
@@ -1,14 +1,12 @@
-package mirror
+package oci_test

 import (
 	"fmt"
 	"net/http/httptest"
 	"net/url"
-	"path/filepath"
 	"testing"

 	"github.com/docker/attest/internal/test"
-	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/google/go-containerregistry/pkg/registry"
@@ -19,9 +17,8 @@ import (
 )

 func TestSavingIndex(t *testing.T) {
-	UnsignedTestImage := filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
 	outputLayout := test.CreateTempDir(t, "", "mirror-test")
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	require.NoError(t, err)

 	server := httptest.NewServer(registry.New())
@@ -33,12 +30,12 @@ func TestSavingIndex(t *testing.T) {
 	indexName := fmt.Sprintf("%s/repo:root", u.Host)
 	output, err := oci.ParseImageSpecs(indexName)
 	require.NoError(t, err)
-	err = SaveIndex(output, attIdx.Index, indexName)
+	err = oci.SaveIndex(output, attIdx.Index, indexName)
 	require.NoError(t, err)

-	ociOutput, err := oci.ParseImageSpecs("oci://" + outputLayout)
+	ociOutput, err := oci.ParseImageSpecs(oci.LocalPrefix + outputLayout)
 	require.NoError(t, err)
-	err = SaveIndex(ociOutput, attIdx.Index, indexName)
+	err = oci.SaveIndex(ociOutput, attIdx.Index, indexName)
 	require.NoError(t, err)
 }

@@ -56,12 +53,12 @@ func TestSavingImage(t *testing.T) {
 	indexName := fmt.Sprintf("%s/repo:root", u.Host)
 	output, err := oci.ParseImageSpec(indexName)
 	require.NoError(t, err)
-	err = SaveImage(output, img, indexName)
+	err = oci.SaveImage(output, img, indexName)
 	require.NoError(t, err)

-	ociOutput, err := oci.ParseImageSpec("oci://" + outputLayout)
+	ociOutput, err := oci.ParseImageSpec(oci.LocalPrefix + outputLayout)
 	require.NoError(t, err)
-	err = SaveImage(ociOutput, img, indexName)
+	err = oci.SaveImage(ociOutput, img, indexName)
 	require.NoError(t, err)
 }

@@ -80,9 +77,9 @@ func TestSavingReferrers(t *testing.T) {
 		MediaType: "application/vnd.oci.image.manifest.v1+json",
 		Digest:    digest,
 	}
-	manifest, err := attest.NewAttestationManifest(subject)
+	manifest, err := attestation.NewManifest(subject)
 	require.NoError(t, err)
-	err = manifest.AddAttestation(ctx, signer, statement, opts)
+	err = manifest.Add(ctx, signer, statement, opts)
 	require.NoError(t, err)
 	server := httptest.NewServer(registry.New(registry.WithReferrersSupport(true)))
 	defer server.Close()
@@ -93,16 +90,18 @@ func TestSavingReferrers(t *testing.T) {
 	indexName := fmt.Sprintf("%s/repo:root", u.Host)
 	output, err := oci.ParseImageSpecs(indexName)
 	require.NoError(t, err)
-	err = SaveReferrers(manifest, output)
+	artifacts, err := manifest.BuildReferringArtifacts()
+	require.NoError(t, err)
+	err = oci.SaveImagesNoTag(artifacts, output)
 	require.NoError(t, err)

-	reg := &test.MockRegistryResolver{
+	reg := &attestation.MockRegistryResolver{
 		Subject:      subject,
-		MockResolver: &test.MockResolver{},
+		MockResolver: &attestation.MockResolver{},
 		ImageNameStr: indexName,
 	}
 	require.NoError(t, err)
-	refResolver, err := oci.NewReferrersAttestationResolver(reg)
+	refResolver, err := attestation.NewReferrersResolver(reg)
 	require.NoError(t, err)
 	attestations, err := refResolver.Attestations(ctx, attestation.VSAPredicateType)
 	require.NoError(t, err)
--- a/pkg/oci/registry.go
+++ b/pkg/oci/registry.go
@@ -4,18 +4,11 @@ import (
 	"context"
 	"fmt"

-	"github.com/docker/attest/pkg/attestation"
-	att "github.com/docker/attest/pkg/attestation"
 	"github.com/google/go-containerregistry/pkg/name"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 )

-type RegistryResolver struct {
-	*RegistryImageDetailsResolver
-	*attestation.Manifest
-}
-
 type RegistryImageDetailsResolver struct {
 	*ImageSpec
 	descriptor *v1.Descriptor
@@ -27,12 +20,6 @@ func NewRegistryImageDetailsResolver(src *ImageSpec) (*RegistryImageDetailsResol
 	}, nil
 }

-func NewRegistryAttestationResolver(src *RegistryImageDetailsResolver) (*RegistryResolver, error) {
-	return &RegistryResolver{
-		RegistryImageDetailsResolver: src,
-	}, nil
-}
-
 func (r *RegistryImageDetailsResolver) ImageName(_ context.Context) (string, error) {
 	return r.Identifier, nil
 }
@@ -72,70 +59,3 @@ func (r *RegistryImageDetailsResolver) ImageDescriptor(ctx context.Context) (*v1
 	}
 	return r.descriptor, nil
 }
-
-func (r *RegistryResolver) Attestations(ctx context.Context, predicateType string) ([]*att.Envelope, error) {
-	if r.Manifest == nil {
-		attest, err := FetchAttestationManifest(ctx, r.Identifier, r.ImageSpec.Platform)
-		if err != nil {
-			return nil, err
-		}
-		r.Manifest = attest
-	}
-	return ExtractEnvelopes(r.Manifest, predicateType)
-}
-
-func FetchAttestationManifest(ctx context.Context, image string, platform *v1.Platform) (*attestation.Manifest, error) {
-	// we want to get to the image index, so ignoring platform for now
-	options := WithOptions(ctx, nil)
-	ref, err := name.ParseReference(image)
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse reference: %w", err)
-	}
-	index, err := remote.Index(ref, options...)
-	if err != nil {
-		return nil, fmt.Errorf("failed to get index: %w", err)
-	}
-	indexManifest, err := index.IndexManifest()
-	if err != nil {
-		return nil, fmt.Errorf("failed to get index manifest: %w", err)
-	}
-	subjectDescriptor, err := imageDescriptor(indexManifest, platform)
-	if err != nil {
-		return nil, fmt.Errorf("failed to obtain image for platform: %w", err)
-	}
-
-	digest := subjectDescriptor.Digest.String()
-	ref, err = name.ParseReference(fmt.Sprintf("%s@%s", ref.Context().Name(), digest))
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse attestation reference: %w", err)
-	}
-
-	attestationDigest, err := attestationDigestForDigest(indexManifest, digest, "attestation-manifest")
-	if err != nil {
-		return nil, fmt.Errorf("failed to obtain attestation for image: %w", err)
-	}
-	ref, err = name.ParseReference(fmt.Sprintf("%s@%s", ref.Context().Name(), attestationDigest))
-	if err != nil {
-		return nil, fmt.Errorf("failed to parse attestation reference: %w", err)
-	}
-	remoteDescriptor, err := remote.Get(ref, options...)
-	if err != nil {
-		return nil, fmt.Errorf("failed to get attestation: %w", err)
-	}
-	attestationImage, err := remoteDescriptor.Image()
-	if err != nil {
-		return nil, fmt.Errorf("failed to get attestation image: %w", err)
-	}
-
-	layers, err := attestation.GetAttestationsFromImage(attestationImage)
-	if err != nil {
-		return nil, fmt.Errorf("failed to get attestations from image: %w", err)
-	}
-	attest := &attestation.Manifest{
-		OriginalLayers:     layers,
-		OriginalDescriptor: &remoteDescriptor.Descriptor,
-		SubjectName:        image,
-		SubjectDescriptor:  subjectDescriptor,
-	}
-	return attest, nil
-}
--- a/pkg/oci/resolver.go
+++ b/pkg/oci/resolver.go
@@ -3,15 +3,9 @@ package oci
 import (
 	"context"

-	att "github.com/docker/attest/pkg/attestation"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 )

-type AttestationResolver interface {
-	ImageDetailsResolver
-	Attestations(ctx context.Context, mediaType string) ([]*att.Envelope, error)
-}
-
 type ImageDetailsResolver interface {
 	ImageName(ctx context.Context) (string, error)
 	ImagePlatform(ctx context.Context) (*v1.Platform, error)
--- a/pkg/oci/types.go
+++ b/pkg/oci/types.go
@@ -1,6 +1,8 @@
 package oci

 import (
+	"bytes"
+	"encoding/json"
 	"fmt"
 	"strings"

@@ -26,12 +28,6 @@ type (
 	}
 )

-type AttestationOptions struct {
-	NoReferrers   bool
-	Attach        bool
-	ReferrersRepo string
-}
-
 type ImageSpecOption func(*ImageSpec) error

 type ImageSpec struct {
@@ -180,3 +176,42 @@ func WithoutTag(image string) (string, error) {
 	repo := ref.Context().Name()
 	return prefix + repo, nil
 }
+
+type EmptyConfigImage struct {
+	v1.Image
+}
+
+func (i *EmptyConfigImage) RawConfigFile() ([]byte, error) {
+	return []byte("{}"), nil
+}
+
+func (i *EmptyConfigImage) Manifest() (*v1.Manifest, error) {
+	mf, err := i.Image.Manifest()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get manifest: %w", err)
+	}
+	mf.Config = v1.Descriptor{
+		MediaType: "application/vnd.oci.empty.v1+json",
+		Size:      2,
+		Digest:    v1.Hash{Algorithm: "sha256", Hex: "44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a"},
+		Data:      []byte("{}"),
+	}
+	return mf, nil
+}
+
+func (i *EmptyConfigImage) RawManifest() ([]byte, error) {
+	mf, err := i.Manifest()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get manifest: %w", err)
+	}
+	return json.Marshal(mf)
+}
+
+func (i *EmptyConfigImage) Digest() (v1.Hash, error) {
+	mb, err := i.RawManifest()
+	if err != nil {
+		return v1.Hash{}, err
+	}
+	digest, _, err := v1.SHA256(bytes.NewReader(mb))
+	return digest, err
+}
--- a/pkg/oci/types_test.go
+++ b/pkg/oci/types_test.go
@@ -0,0 +1,21 @@
+package oci
+
+import (
+	"testing"
+
+	"github.com/docker/attest/internal/util"
+	"github.com/google/go-containerregistry/pkg/v1/empty"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestEmptyConfigImageDigest(t *testing.T) {
+	empty := empty.Image
+	img := EmptyConfigImage{Image: empty}
+	mf, err := img.RawManifest()
+	require.NoError(t, err)
+	hash := util.SHA256Hex(mf)
+	digest, err := img.Digest()
+	require.NoError(t, err)
+	assert.Equal(t, digest.Hex, hash)
+}
--- a/pkg/policy/README.md
+++ b/pkg/policy/README.md
@@ -0,0 +1,2 @@
+## policy
+This package is for attestation policy mapping and evaluation.
--- a/pkg/policy/evaluator.go
+++ b/pkg/policy/evaluator.go
@@ -4,7 +4,7 @@ import (
 	"context"
 	"fmt"

-	"github.com/docker/attest/pkg/oci"
+	"github.com/docker/attest/pkg/attestation"
 )

 type policyEvaluatorCtxKeyType struct{}
@@ -26,5 +26,5 @@ func GetPolicyEvaluator(ctx context.Context) (Evaluator, error) {
 }

 type Evaluator interface {
-	Evaluate(ctx context.Context, resolver oci.AttestationResolver, pctx *Policy, input *Input) (*Result, error)
+	Evaluate(ctx context.Context, resolver attestation.Resolver, pctx *Policy, input *Input) (*Result, error)
 }
--- a/pkg/policy/mock.go
+++ b/pkg/policy/mock.go
@@ -3,14 +3,14 @@ package policy
 import (
 	"context"

-	"github.com/docker/attest/pkg/oci"
+	"github.com/docker/attest/pkg/attestation"
 )

 type MockPolicyEvaluator struct {
-	EvaluateFunc func(ctx context.Context, resolver oci.AttestationResolver, pctx *Policy, input *Input) (*Result, error)
+	EvaluateFunc func(ctx context.Context, resolver attestation.Resolver, pctx *Policy, input *Input) (*Result, error)
 }

-func (pe *MockPolicyEvaluator) Evaluate(ctx context.Context, resolver oci.AttestationResolver, pctx *Policy, input *Input) (*Result, error) {
+func (pe *MockPolicyEvaluator) Evaluate(ctx context.Context, resolver attestation.Resolver, pctx *Policy, input *Input) (*Result, error) {
 	if pe.EvaluateFunc != nil {
 		return pe.EvaluateFunc(ctx, resolver, pctx, input)
 	}
@@ -19,7 +19,7 @@ func (pe *MockPolicyEvaluator) Evaluate(ctx context.Context, resolver oci.Attest

 func GetMockPolicy() Evaluator {
 	return &MockPolicyEvaluator{
-		EvaluateFunc: func(_ context.Context, _ oci.AttestationResolver, _ *Policy, _ *Input) (*Result, error) {
+		EvaluateFunc: func(_ context.Context, _ attestation.Resolver, _ *Policy, _ *Input) (*Result, error) {
 			return AllowedResult(), nil
 		},
 	}
--- a/pkg/policy/policy.go
+++ b/pkg/policy/policy.go
@@ -8,6 +8,8 @@ import (
 	"path/filepath"

 	"github.com/distribution/reference"
+	"github.com/docker/attest/internal/util"
+	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/config"
 	"github.com/docker/attest/pkg/oci"
 )
@@ -16,6 +18,8 @@ func resolveLocalPolicy(opts *Options, mapping *config.PolicyMapping, imageName
 	if opts.LocalPolicyDir == "" {
 		return nil, fmt.Errorf("local policy dir not set")
 	}
+	var URI string
+	var digest map[string]string
 	files := make([]*File, 0, len(mapping.Files))
 	for _, f := range mapping.Files {
 		filename := f.Path
@@ -28,10 +32,24 @@ func resolveLocalPolicy(opts *Options, mapping *config.PolicyMapping, imageName
 			Path:    filename,
 			Content: fileContents,
 		})
+		// if the file is a policy file, store the URI and digest
+		if filepath.Ext(filename) == ".rego" {
+			// TODO: support multiple rego files, need some way to identify the main policy file
+			if URI != "" {
+				return nil, fmt.Errorf("multiple policy files found in policy mapping")
+			}
+			URI = filePath
+			digest = map[string]string{"sha256": util.SHA256Hex(fileContents)}
+		}
+	}
+	if URI == "" {
+		return nil, fmt.Errorf("no policy file found in policy mapping")
 	}
 	policy := &Policy{
 		InputFiles: files,
 		Mapping:    mapping,
+		URI:        URI,
+		Digest:     digest,
 	}
 	if imageName != matchedName {
 		policy.ResolvedName = matchedName
@@ -40,21 +58,37 @@ func resolveLocalPolicy(opts *Options, mapping *config.PolicyMapping, imageName
 }

 func resolveTUFPolicy(opts *Options, mapping *config.PolicyMapping, imageName string, matchedName string) (*Policy, error) {
+	var URI string
+	var digest map[string]string
 	files := make([]*File, 0, len(mapping.Files))
 	for _, f := range mapping.Files {
 		filename := f.Path
-		_, fileContents, err := opts.TUFClient.DownloadTarget(filename, filepath.Join(opts.LocalTargetsDir, filename))
+		file, err := opts.TUFClient.DownloadTarget(filename, filepath.Join(opts.LocalTargetsDir, filename))
 		if err != nil {
 			return nil, fmt.Errorf("failed to download policy file %s: %w", filename, err)
 		}
 		files = append(files, &File{
 			Path:    filename,
-			Content: fileContents,
+			Content: file.Data,
 		})
+		// if the file is a policy file, store the URI and digest
+		if filepath.Ext(filename) == ".rego" {
+			// TODO: support multiple rego files, need some way to identify the main policy file
+			if URI != "" {
+				return nil, fmt.Errorf("multiple policy files found in policy mapping")
+			}
+			URI = file.TargetURI
+			digest = map[string]string{"sha256": file.Digest}
+		}
+	}
+	if URI == "" {
+		return nil, fmt.Errorf("no policy file found in policy mapping")
 	}
 	policy := &Policy{
 		InputFiles: files,
 		Mapping:    mapping,
+		URI:        URI,
+		Digest:     digest,
 	}
 	if imageName != matchedName {
 		policy.ResolvedName = matchedName
@@ -211,27 +245,28 @@ func normalizeImageName(imageName string) (string, error) {
 func CreateImageDetailsResolver(imageSource *oci.ImageSpec) (oci.ImageDetailsResolver, error) {
 	switch imageSource.Type {
 	case oci.OCI:
-		return oci.NewOCILayoutAttestationResolver(imageSource)
+		return attestation.NewOCILayoutResolver(imageSource)
 	case oci.Docker:
 		return oci.NewRegistryImageDetailsResolver(imageSource)
 	}
 	return nil, fmt.Errorf("unsupported image source type: %s", imageSource.Type)
 }

-func CreateAttestationResolver(resolver oci.ImageDetailsResolver, mapping *config.PolicyMapping) (oci.AttestationResolver, error) {
-	switch resolver := resolver.(type) {
-	case *oci.RegistryImageDetailsResolver:
-		if mapping.Attestations != nil && mapping.Attestations.Style == config.AttestationStyleAttached {
-			return oci.NewRegistryAttestationResolver(resolver)
-		} else {
-			if mapping.Attestations != nil && mapping.Attestations.Repo != "" {
-				return oci.NewReferrersAttestationResolver(resolver, oci.WithReferrersRepo(mapping.Attestations.Repo))
+func CreateAttestationResolver(resolver oci.ImageDetailsResolver, mapping *config.PolicyMapping) (attestation.Resolver, error) {
+	if mapping.Attestations != nil {
+		if mapping.Attestations.Style == config.AttestationStyleAttached {
+			switch resolver := resolver.(type) {
+			case *oci.RegistryImageDetailsResolver:
+				return attestation.NewRegistryResolver(resolver)
+			case *attestation.LayoutResolver:
+				return resolver, nil
+			default:
+				return nil, fmt.Errorf("unsupported image details resolver type: %T", resolver)
 			}
-			return oci.NewReferrersAttestationResolver(resolver)
 		}
-	case *oci.LayoutResolver:
-		return resolver, nil
-	default:
-		return nil, fmt.Errorf("unsupported image details resolver type: %T", resolver)
+		if mapping.Attestations.Repo != "" {
+			return attestation.NewReferrersResolver(resolver, attestation.WithReferrersRepo(mapping.Attestations.Repo))
+		}
 	}
+	return attestation.NewReferrersResolver(resolver)
 }
--- a/pkg/policy/policy_test.go
+++ b/pkg/policy/policy_test.go
@@ -32,33 +32,34 @@ func loadAttestation(t *testing.T, path string) *attestation.Envelope {

 func TestRegoEvaluator_Evaluate(t *testing.T) {
 	ctx, _ := test.Setup(t)
-	errorStr := "failed to resolve policy by id: policy with id non-existent-policy-id not found"
+	resolveErrorStr := "failed to resolve policy by id: policy with id non-existent-policy-id not found"
 	TestDataPath := filepath.Join("..", "..", "test", "testdata")
 	ExampleAttestation := filepath.Join(TestDataPath, "example_attestation.json")

 	re := policy.NewRegoEvaluator(true)

-	defaultResolver := test.MockResolver{
+	defaultResolver := attestation.MockResolver{
 		Envs: []*attestation.Envelope{loadAttestation(t, ExampleAttestation)},
 	}

 	testCases := []struct {
-		repo          string
-		expectSuccess bool
-		isCanonical   bool
-		resolver      oci.AttestationResolver
-		policy        *policy.Options
-		policyID      string
-		errorStr      string
+		repo            string
+		expectSuccess   bool
+		isCanonical     bool
+		resolver        attestation.Resolver
+		policy          *policy.Options
+		policyID        string
+		resolveErrorStr string
 	}{
 		{repo: "testdata/mock-tuf-allow", expectSuccess: true, isCanonical: false, resolver: defaultResolver},
 		{repo: "testdata/mock-tuf-allow", expectSuccess: true, isCanonical: false, resolver: defaultResolver, policyID: "docker-official-images"},
-		{repo: "testdata/mock-tuf-allow", expectSuccess: false, isCanonical: false, resolver: defaultResolver, policyID: "non-existent-policy-id", errorStr: errorStr},
+		{repo: "testdata/mock-tuf-allow", expectSuccess: false, isCanonical: false, resolver: defaultResolver, policyID: "non-existent-policy-id", resolveErrorStr: resolveErrorStr},
 		{repo: "testdata/mock-tuf-deny", expectSuccess: false, isCanonical: false, resolver: defaultResolver},
 		{repo: "testdata/mock-tuf-verify-sig", expectSuccess: true, isCanonical: false, resolver: defaultResolver},
 		{repo: "testdata/mock-tuf-wrong-key", expectSuccess: false, isCanonical: false, resolver: defaultResolver},
 		{repo: "testdata/mock-tuf-allow-canonical", expectSuccess: true, isCanonical: true, resolver: defaultResolver},
 		{repo: "testdata/mock-tuf-allow-canonical", expectSuccess: false, isCanonical: false, resolver: defaultResolver},
+		{repo: "testdata/mock-tuf-no-rego", expectSuccess: false, isCanonical: false, resolver: defaultResolver, resolveErrorStr: "no policy file found in policy mapping"},
 	}

 	for _, tc := range testCases {
@@ -86,9 +87,9 @@ func TestRegoEvaluator_Evaluate(t *testing.T) {
 			resolver, err := policy.CreateImageDetailsResolver(src)
 			require.NoError(t, err)
 			policy, err := policy.ResolvePolicy(ctx, resolver, tc.policy)
-			if tc.errorStr != "" {
+			if tc.resolveErrorStr != "" {
 				require.Error(t, err)
-				assert.Contains(t, err.Error(), tc.errorStr)
+				assert.Contains(t, err.Error(), tc.resolveErrorStr)
 				return
 			}
 			require.NoErrorf(t, err, "failed to resolve policy")
@@ -115,3 +116,64 @@ func TestLoadingMappings(t *testing.T) {
 		}
 	}
 }
+
+func TestCreateAttestationResolver(t *testing.T) {
+	mockResolver := attestation.MockResolver{
+		Envs: []*attestation.Envelope{},
+	}
+	layoutResolver := &attestation.LayoutResolver{}
+	registryResolver := &oci.RegistryImageDetailsResolver{}
+
+	nilRepoReferrers := &config.PolicyMapping{
+		Attestations: &config.AttestationConfig{
+			Style: config.AttestationStyleReferrers,
+		},
+	}
+	referrers := &config.PolicyMapping{
+		Attestations: &config.AttestationConfig{
+			Repo:  "localhost:5000/repo",
+			Style: config.AttestationStyleReferrers,
+		},
+	}
+	attached := &config.PolicyMapping{
+		Attestations: &config.AttestationConfig{
+			Style: config.AttestationStyleAttached,
+		},
+	}
+
+	testCases := []struct {
+		name     string
+		resolver oci.ImageDetailsResolver
+		mapping  *config.PolicyMapping
+		errorStr string
+	}{
+		{name: "referrers", resolver: layoutResolver, mapping: referrers},
+		{name: "referrers (no mapped repo)", resolver: layoutResolver, mapping: nilRepoReferrers},
+		{name: "referrers (no mapping)", resolver: layoutResolver, mapping: &config.PolicyMapping{Attestations: nil}},
+		{name: "attached (registry)", resolver: registryResolver, mapping: attached},
+		{name: "attached (layout)", resolver: layoutResolver, mapping: attached},
+		{name: "attached (unsupported)", resolver: mockResolver, mapping: attached, errorStr: "unsupported image details resolver type"},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			resolver, err := policy.CreateAttestationResolver(tc.resolver, tc.mapping)
+			if tc.errorStr == "" {
+				require.NoError(t, err)
+			} else {
+				assert.Contains(t, err.Error(), tc.errorStr)
+			}
+			if tc.mapping.Attestations == nil {
+				return
+			}
+			switch resolver.(type) {
+			case *attestation.ReferrersResolver:
+				assert.Equal(t, tc.mapping.Attestations.Style, config.AttestationStyleReferrers)
+			case *attestation.RegistryResolver:
+				assert.Equal(t, tc.mapping.Attestations.Style, config.AttestationStyleAttached)
+			case *attestation.LayoutResolver:
+				assert.Equal(t, tc.mapping.Attestations.Style, config.AttestationStyleAttached)
+			}
+		})
+	}
+}
--- a/pkg/policy/rego.go
+++ b/pkg/policy/rego.go
@@ -7,8 +7,7 @@ import (
 	"os"
 	"path/filepath"

-	att "github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/oci"
+	"github.com/docker/attest/pkg/attestation"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	"github.com/open-policy-agent/opa/ast"
 	"github.com/open-policy-agent/opa/rego"
@@ -36,7 +35,7 @@ func NewRegoEvaluator(debug bool) Evaluator {
 	}
 }

-func (re *regoEvaluator) Evaluate(ctx context.Context, resolver oci.AttestationResolver, pctx *Policy, input *Input) (*Result, error) {
+func (re *regoEvaluator) Evaluate(ctx context.Context, resolver attestation.Resolver, pctx *Policy, input *Input) (*Result, error) {
 	var regoOpts []func(*rego.Rego)

 	// Create a new in-memory store
@@ -170,7 +169,7 @@ func handleErrors2(f func(rCtx *rego.BuiltinContext, a, b *ast.Term) (*ast.Term,
 	}
 }

-func RegoFunctions(resolver oci.AttestationResolver) []*tester.Builtin {
+func RegoFunctions(resolver attestation.Resolver) []*tester.Builtin {
 	return []*tester.Builtin{
 		{
 			Decl: verifyDecl,
@@ -197,7 +196,7 @@ func RegoFunctions(resolver oci.AttestationResolver) []*tester.Builtin {
 	}
 }

-func fetchInTotoAttestations(resolver oci.AttestationResolver) rego.Builtin1 {
+func fetchInTotoAttestations(resolver attestation.Resolver) rego.Builtin1 {
 	return func(rCtx rego.BuiltinContext, predicateTypeTerm *ast.Term) (*ast.Term, error) {
 		predicateTypeStr, ok := predicateTypeTerm.Value.(ast.String)
 		if !ok {
@@ -228,8 +227,8 @@ func fetchInTotoAttestations(resolver oci.AttestationResolver) rego.Builtin1 {
 }

 func verifyInTotoEnvelope(rCtx *rego.BuiltinContext, envTerm, optsTerm *ast.Term) (*ast.Term, error) {
-	env := new(att.Envelope)
-	opts := new(att.VerifyOptions)
+	env := new(attestation.Envelope)
+	opts := new(attestation.VerifyOptions)
 	err := ast.As(envTerm.Value, env)
 	if err != nil {
 		return nil, fmt.Errorf("failed to cast envelope: %w", err)
@@ -239,7 +238,7 @@ func verifyInTotoEnvelope(rCtx *rego.BuiltinContext, envTerm, optsTerm *ast.Term
 		return nil, fmt.Errorf("failed to cast verifier options: %w", err)
 	}

-	payload, err := att.VerifyDSSE(rCtx.Context, env, opts)
+	payload, err := attestation.VerifyDSSE(rCtx.Context, env, opts)
 	if err != nil {
 		return nil, err
 	}
--- a/pkg/policy/testdata/mock-tuf-no-rego/doi/policy.yaml
+++ b/pkg/policy/testdata/mock-tuf-no-rego/doi/policy.yaml
@@ -0,0 +1 @@
+policy: "this is not rego"
--- a/pkg/policy/testdata/mock-tuf-no-rego/mapping.yaml
+++ b/pkg/policy/testdata/mock-tuf-no-rego/mapping.yaml
@@ -0,0 +1,11 @@
+# map repos to policies
+version: v1
+kind: policy-mapping
+policies:
+  - id: docker-official-images
+    description: Docker Official Images
+    files:
+      - path: doi/policy.yaml
+rules:
+  - pattern: "^docker[.]io/library/(.*)$"
+    policy-id: docker-official-images
--- a/pkg/policy/types.go
+++ b/pkg/policy/types.go
@@ -40,6 +40,8 @@ type Policy struct {
 	Query        string
 	Mapping      *config.PolicyMapping
 	ResolvedName string
+	URI          string
+	Digest       map[string]string
 }

 type Input struct {
--- a/pkg/signerverifier/README.md
+++ b/pkg/signerverifier/README.md
@@ -0,0 +1,2 @@
+## signerverifier
+This package implements methods to sign and verify attestation envelopes.
--- a/pkg/tlog/README.md
+++ b/pkg/tlog/README.md
@@ -0,0 +1,2 @@
+## tlog
+This package implements transparency logging.
--- a/pkg/tuf/README.md
+++ b/pkg/tuf/README.md
@@ -0,0 +1,2 @@
+## tuf
+This package implements TUF clients for http and oci data sources.
--- a/pkg/tuf/example_registry_test.go
+++ b/pkg/tuf/example_registry_test.go
@@ -28,16 +28,13 @@ func ExampleNewClient_registry() {

 	// get trusted tuf metadata
 	trustedMetadata := registryClient.GetMetadata()
-	if err != nil {
-		panic(err)
-	}

 	// top-level target files
 	targets := trustedMetadata.Targets[metadata.TARGETS].Signed.Targets

 	for _, t := range targets {
 		// download target files
-		_, _, err := registryClient.DownloadTarget(t.Path, filepath.Join(tufOutputPath, "download"))
+		_, err := registryClient.DownloadTarget(t.Path, filepath.Join(tufOutputPath, "download"))
 		if err != nil {
 			panic(err)
 		}
--- a/pkg/tuf/mock.go
+++ b/pkg/tuf/mock.go
@@ -4,6 +4,8 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+
+	"github.com/docker/attest/internal/util"
 )

 type MockTufClient struct {
@@ -24,10 +26,11 @@ func NewMockTufClient(srcPath string, dstPath string) *MockTufClient {
 	}
 }

-func (dc *MockTufClient) DownloadTarget(target string, filePath string) (actualFilePath string, data []byte, err error) {
-	src, err := os.Open(filepath.Join(dc.srcPath, target))
+func (dc *MockTufClient) DownloadTarget(target string, filePath string) (file *TargetFile, err error) {
+	targetPath := filepath.Join(dc.srcPath, target)
+	src, err := os.Open(targetPath)
 	if err != nil {
-		return "", nil, err
+		return nil, err
 	}
 	defer src.Close()

@@ -40,11 +43,11 @@ func (dc *MockTufClient) DownloadTarget(target string, filePath string) (actualF

 	err = os.MkdirAll(filepath.Dir(dstFilePath), os.ModePerm)
 	if err != nil {
-		return "", nil, err
+		return nil, err
 	}
 	dst, err := os.Create(dstFilePath)
 	if err != nil {
-		return "", nil, err
+		return nil, err
 	}
 	defer dst.Close()

@@ -53,10 +56,10 @@ func (dc *MockTufClient) DownloadTarget(target string, filePath string) (actualF

 	b, err := io.ReadAll(tee)
 	if err != nil {
-		return "", nil, err
+		return nil, err
 	}

-	return dstFilePath, b, nil
+	return &TargetFile{ActualFilePath: dstFilePath, TargetURI: targetPath, Data: b, Digest: util.SHA256Hex(b)}, nil
 }

 type MockVersionChecker struct {
--- a/pkg/tuf/registry_test.go
+++ b/pkg/tuf/registry_test.go
@@ -32,6 +32,9 @@ const (
 	tufTargetMediaType = "application/vnd.tuf.target"
 	testRole           = "test-role"
 	tufMetadataRepo    = "tuf-metadata"
+	targetsPath        = "/tuf-targets"
+	metadataPath       = "/tuf-metadata"
+	targetsRepo        = "test" + targetsPath
 )

 func TestRegistryFetcher(t *testing.T) {
@@ -44,9 +47,9 @@ func TestRegistryFetcher(t *testing.T) {
 	}()
 	LoadRegistryTestData(t, regAddr, OCITUFTestDataPath)

-	metadataRepo := regAddr.Host + "/tuf-metadata"
+	metadataRepo := regAddr.Host + metadataPath
 	metadataImgTag := LatestTag
-	targetsRepo := regAddr.Host + "/tuf-targets"
+	targetsRepo := regAddr.Host + targetsPath
 	targetFile := "test.txt"
 	delegatedRole := testRole
 	dir := CreateTempDir(t, "", "tuf_temp")
@@ -122,7 +125,7 @@ func TestFindFileInManifest(t *testing.T) {
 	// make test image manifest
 	file := "test.json"
 	data := []byte("test")
-	hash := v1.Hash{Algorithm: "sha256", Hex: util.SHA256Hex(data)}
+	hash := v1.Hash{Hex: util.SHA256Hex(data)}
 	img := empty.Image
 	img = mutate.MediaType(img, types.OCIManifestSchema1)
 	img = mutate.ConfigMediaType(img, types.OCIConfigJSON)
@@ -150,7 +153,6 @@ func TestFindFileInManifest(t *testing.T) {
 	indexManifest, err := idx.RawManifest()
 	assert.NoError(t, err)
 	// cache image layer
-	targetsRepo := "test/tuf-targets"
 	d := &RegistryFetcher{
 		cache:       NewImageCache(),
 		targetsRepo: targetsRepo,
@@ -183,9 +185,8 @@ func TestFindFileInManifest(t *testing.T) {
 }

 func TestParseImgRef(t *testing.T) {
-	metadataRepo := "test/tuf-metadata"
+	metadataRepo := "test" + metadataPath
 	metadataTag := LatestTag
-	targetsRepo := "test/tuf-targets"
 	delegatedRole := testRole
 	testCases := []struct {
 		name         string
--- a/pkg/tuf/tuf.go
+++ b/pkg/tuf/tuf.go
@@ -36,7 +36,7 @@ var (
 )

 type Downloader interface {
-	DownloadTarget(target, filePath string) (actualFilePath string, data []byte, err error)
+	DownloadTarget(target, filePath string) (file *TargetFile, err error)
 }

 type Client struct {
@@ -44,6 +44,13 @@ type Client struct {
 	cfg     *config.UpdaterConfig
 }

+type TargetFile struct {
+	ActualFilePath string
+	TargetURI      string
+	Digest         string
+	Data           []byte
+}
+
 // NewClient creates a new TUF client.
 func NewClient(initialRoot []byte, tufPath, metadataSource, targetsSource string, versionChecker VersionChecker) (*Client, error) {
 	var tufSource Source
@@ -119,40 +126,69 @@ func NewClient(initialRoot []byte, tufPath, metadataSource, targetsSource string
 	return client, nil
 }

+func (t *Client) generateTargetURI(target *metadata.TargetFiles, digest string) (string, error) {
+	switch fetcher := t.cfg.Fetcher.(type) {
+	case *RegistryFetcher:
+		return fmt.Sprintf("%s@sha256:%s", t.cfg.RemoteTargetsURL, digest), nil
+	case *fetcher.DefaultFetcher:
+		targetBaseURL := ensureTrailingSlash(t.cfg.RemoteTargetsURL)
+		targetRemotePath := target.Path
+		// if PrefixTargetsWithHash is set, we need to prefix the target name with the hash and handle subdirectories
+		// similar logic to https://github.com/theupdateframework/go-tuf/blob/f95222bdd22d2ac4e5b8ed6fe912b645e213c3b5/metadata/updater/updater.go#L227-L247
+		if t.cfg.PrefixTargetsWithHash {
+			baseName := filepath.Base(targetRemotePath)
+			dirName, ok := strings.CutSuffix(targetRemotePath, "/"+baseName)
+			if !ok {
+				// <hash>.<target-name>
+				targetRemotePath = fmt.Sprintf("%s.%s", digest, baseName)
+			} else {
+				// <dir-prefix>/<hash>.<target-name>
+				targetRemotePath = fmt.Sprintf("%s/%s.%s", dirName, digest, baseName)
+			}
+		}
+		return fmt.Sprintf("%s%s", targetBaseURL, targetRemotePath), nil
+	default:
+		return "", fmt.Errorf("unsupported fetcher type: %T", fetcher)
+	}
+}
+
 // DownloadTarget downloads the target file using Updater. The Updater gets the target
 // information, verifies if the target is already cached, and if it is not cached,
 // downloads the target file.
-func (t *Client) DownloadTarget(target string, filePath string) (actualFilePath string, data []byte, err error) {
+func (t *Client) DownloadTarget(target string, filePath string) (file *TargetFile, err error) {
 	// search if the desired target is available
 	targetInfo, err := t.updater.GetTargetInfo(target)
 	if err != nil {
-		return "", nil, err
+		return nil, err
 	}

 	// check if filePath exists and create the directory if it doesn't
 	if _, err := os.Stat(filepath.Dir(filePath)); os.IsNotExist(err) {
 		err = os.MkdirAll(filepath.Dir(filePath), os.ModePerm)
 		if err != nil {
-			return "", nil, fmt.Errorf("failed to create target download directory '%s': %w", filepath.Dir(filePath), err)
+			return nil, fmt.Errorf("failed to create target download directory '%s': %w", filepath.Dir(filePath), err)
 		}
 	}

 	// target is available, so let's see if the target is already present locally
-	actualFilePath, data, err = t.updater.FindCachedTarget(targetInfo, filePath)
+	actualFilePath, data, err := t.updater.FindCachedTarget(targetInfo, filePath)
 	if err != nil {
-		return "", nil, fmt.Errorf("failed while finding a cached target: %w", err)
+		return nil, fmt.Errorf("failed while finding a cached target: %w", err)
 	}
 	if data != nil {
-		return actualFilePath, data, err
+		digest := util.SHA256Hex(data)
+		uri, err := t.generateTargetURI(targetInfo, digest)
+		return &TargetFile{ActualFilePath: actualFilePath, TargetURI: uri, Data: data, Digest: digest}, err
 	}

 	// target is not present locally, so let's try to download it
 	actualFilePath, data, err = t.updater.DownloadTarget(targetInfo, filePath, "")
 	if err != nil {
-		return "", nil, fmt.Errorf("failed to download target file %s - %w", target, err)
+		return nil, fmt.Errorf("failed to download target file %s - %w", target, err)
 	}
-
-	return actualFilePath, data, err
+	digest := util.SHA256Hex(data)
+	uri, err := t.generateTargetURI(targetInfo, digest)
+	return &TargetFile{ActualFilePath: actualFilePath, TargetURI: uri, Data: data, Digest: digest}, err
 }

 func (t *Client) GetMetadata() trustedmetadata.TrustedMetadata {
--- a/pkg/tuf/tuf_test.go
+++ b/pkg/tuf/tuf_test.go
@@ -122,14 +122,14 @@ func TestDownloadTarget(t *testing.T) {
 		targets := trustedMetadata.Targets[metadata.TARGETS].Signed.Targets
 		for _, target := range targets {
 			// download target files
-			_, _, err := tufClient.DownloadTarget(target.Path, filepath.Join(tufPath, "download"))
+			_, err := tufClient.DownloadTarget(target.Path, filepath.Join(tufPath, "download"))
 			assert.NoErrorf(t, err, "Failed to download target: %v", err)
 		}

 		// download delegated target
 		targetInfo, err := tufClient.updater.GetTargetInfo(delegatedTargetFile)
 		assert.NoError(t, err)
-		_, _, err = tufClient.DownloadTarget(targetInfo.Path, filepath.Join(tufPath, targetInfo.Path))
+		_, err = tufClient.DownloadTarget(targetInfo.Path, filepath.Join(tufPath, targetInfo.Path))
 		assert.NoError(t, err)
 	}
 }
--- a/pkg/tuf/version.go
+++ b/pkg/tuf/version.go
@@ -67,11 +67,11 @@ func (vc *DefaultVersionChecker) CheckVersion(client Downloader) error {

 	// see https://github.com/Masterminds/semver/blob/v3.2.1/README.md#checking-version-constraints
 	// for more information on the expected format of the version constraints in the TUF repo
-	_, versionConstraintsBytes, err := client.DownloadTarget("version-constraints", "")
+	target, err := client.DownloadTarget("version-constraints", "")
 	if err != nil {
 		return fmt.Errorf("failed to download version-constraints: %w", err)
 	}
-	versionConstraints, err := semver.NewConstraint(string(versionConstraintsBytes))
+	versionConstraints, err := semver.NewConstraint(string(target.Data))
 	if err != nil {
 		return fmt.Errorf("failed to parse minimum version: %w", err)
 	}
--- a/scripts/README.md
+++ b/scripts/README.md
@@ -0,0 +1,4 @@
+## scripts
+This directory contains project scripts.
+
+`gen-testdata.sh` - used to generate static test data saved in `/test/testdata/`
--- a/test/README.md
+++ b/test/README.md
@@ -0,0 +1,2 @@
+## test
+This directory contains static `testdata` used to run go tests.
Author	SHA1	Message	Date
Joel Kamp	a4a0bf3cbe	Merge pull request #124 from docker/feat-generate-vsa-policy-uri feat: add `digest` and `downloadLocation` to VSA policy	2024-08-14 16:50:16 -05:00
mrjoelkamp	52499053d2	feat: add no policy file error	2024-08-14 16:25:41 -05:00
mrjoelkamp	5f17f97229	test: change test to use yaml file instead	2024-08-14 16:13:36 -05:00
mrjoelkamp	8d8f09661f	test: add mapping no rego test	2024-08-14 16:10:54 -05:00
mrjoelkamp	059ee8926c	refactor: move fullURL only needed for DefaultFetcher	2024-08-14 15:27:02 -05:00
mrjoelkamp	cb47507650	chore: pr comments	2024-08-14 15:01:01 -05:00
Joel Kamp	7c0966de81	Update README.md Co-authored-by: David Dooling <141646279+whalelines@users.noreply.github.com>	2024-08-14 14:39:06 -05:00
mrjoelkamp	2bf7dec72e	feat: add policy.downloadLocation	2024-08-14 12:52:36 -05:00
mrjoelkamp	6de792c1b5	docs: update README with policy.digest	2024-08-14 11:33:15 -05:00
mrjoelkamp	d2a8348ae8	feat: generate vsa policy value from file	2024-08-14 10:57:15 -05:00
Joel Kamp	8c6df28540	Merge pull request #122 from docker/feat-mirror-empty-config-image feat: mirror empty config image	2024-08-13 10:09:35 -05:00
mrjoelkamp	5162cfa404	refactor: ensure tests are in correct pkg	2024-08-13 10:03:33 -05:00
mrjoelkamp	72f6517b2c	refactor: move empty config image test	2024-08-13 08:26:36 -05:00
mrjoelkamp	84cadeb97e	feat: output comments	2024-08-13 08:13:27 -05:00
mrjoelkamp	57a61cc266	fix: e2e auth test	2024-08-12 16:54:44 -05:00
mrjoelkamp	5a772633b0	feat: use EmptyConfigImage for mirror	2024-08-12 16:43:42 -05:00
mrjoelkamp	1febc55a19	fix: cyclical imports	2024-08-12 16:36:18 -05:00
mrjoelkamp	0db96d56aa	fix: err check not needed	2024-08-12 14:20:24 -05:00
Joel Kamp	d97d20eb93	Merge pull request #121 from docker/dependabot/go_modules/google.golang.org/api-0.191.0 feat(deps): bump google.golang.org/api from 0.190.0 to 0.191.0	2024-08-08 15:28:52 -05:00
Joel Kamp	42390b5fc2	Merge branch 'main' into dependabot/go_modules/google.golang.org/api-0.191.0	2024-08-08 15:18:54 -05:00
Joel Kamp	70e6345942	Merge pull request #119 from docker/dependabot/go_modules/github.com/sigstore/cosign/v2-2.4.0 feat(deps): bump github.com/sigstore/cosign/v2 from 2.3.0 to 2.4.0	2024-08-08 15:18:19 -05:00
dependabot[bot]	f853875eea	feat(deps): bump github.com/sigstore/cosign/v2 from 2.3.0 to 2.4.0 Bumps [github.com/sigstore/cosign/v2](https://github.com/sigstore/cosign) from 2.3.0 to 2.4.0. - [Release notes](https://github.com/sigstore/cosign/releases) - [Changelog](https://github.com/sigstore/cosign/blob/main/CHANGELOG.md) - [Commits](https://github.com/sigstore/cosign/compare/v2.3.0...v2.4.0) --- updated-dependencies: - dependency-name: github.com/sigstore/cosign/v2 dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com>	2024-08-08 20:11:27 +00:00
Joel Kamp	050497e5a7	Merge pull request #118 from docker/dependabot/go_modules/github.com/sigstore/sigstore/pkg/signature/kms/aws-1.8.8 feat(deps): bump github.com/sigstore/sigstore/pkg/signature/kms/aws from 1.8.7 to 1.8.8	2024-08-08 15:09:20 -05:00
dependabot[bot]	d69334a1e6	feat(deps): bump google.golang.org/api from 0.190.0 to 0.191.0 Bumps [google.golang.org/api](https://github.com/googleapis/google-api-go-client) from 0.190.0 to 0.191.0. - [Release notes](https://github.com/googleapis/google-api-go-client/releases) - [Changelog](https://github.com/googleapis/google-api-go-client/blob/main/CHANGES.md) - [Commits](https://github.com/googleapis/google-api-go-client/compare/v0.190.0...v0.191.0) --- updated-dependencies: - dependency-name: google.golang.org/api dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com>	2024-08-08 20:00:21 +00:00
dependabot[bot]	a84268b133	feat(deps): bump github.com/sigstore/sigstore/pkg/signature/kms/aws Bumps [github.com/sigstore/sigstore/pkg/signature/kms/aws](https://github.com/sigstore/sigstore) from 1.8.7 to 1.8.8. - [Release notes](https://github.com/sigstore/sigstore/releases) - [Commits](https://github.com/sigstore/sigstore/compare/v1.8.7...v1.8.8) --- updated-dependencies: - dependency-name: github.com/sigstore/sigstore/pkg/signature/kms/aws dependency-type: direct:production update-type: version-update:semver-patch ... Signed-off-by: dependabot[bot] <support@github.com>	2024-08-08 20:00:19 +00:00
Joel Kamp	2cd2e2da96	Merge pull request #117 from docker/dependabot/go_modules/github.com/sigstore/sigstore/pkg/signature/kms/gcp-1.8.8 feat(deps): bump github.com/sigstore/sigstore/pkg/signature/kms/gcp from 1.8.7 to 1.8.8	2024-08-08 14:58:19 -05:00
Joel Kamp	f1ece6893f	Merge branch 'main' into dependabot/go_modules/github.com/sigstore/sigstore/pkg/signature/kms/gcp-1.8.8	2024-08-08 14:48:59 -05:00
Joel Kamp	116b9ea770	Merge pull request #120 from docker/refactor-referrers-output feat!: push attestation artifacts by digest	2024-08-08 14:48:42 -05:00
mrjoelkamp	d291912208	refactor!: move oci output from mirror to oci pkg BREAKING_CHANGE: output methods to save and push images are now part of the oci pkg	2024-08-08 14:23:46 -05:00
mrjoelkamp	9cad88a687	fix: EmptyConfigImage digest	2024-08-08 13:06:56 -05:00
mrjoelkamp	77ccbc097b	feat: use docker/go-containerregistry	2024-08-08 11:37:45 -05:00
mrjoelkamp	45927967c8	test: debug push	2024-08-08 10:04:41 -05:00
mrjoelkamp	9aa56e564d	feat: push attestation artifacts by digest	2024-08-07 15:19:48 -05:00
dependabot[bot]	6d0a6de520	feat(deps): bump github.com/sigstore/sigstore/pkg/signature/kms/gcp Bumps [github.com/sigstore/sigstore/pkg/signature/kms/gcp](https://github.com/sigstore/sigstore) from 1.8.7 to 1.8.8. - [Release notes](https://github.com/sigstore/sigstore/releases) - [Commits](https://github.com/sigstore/sigstore/compare/v1.8.7...v1.8.8) --- updated-dependencies: - dependency-name: github.com/sigstore/sigstore/pkg/signature/kms/gcp dependency-type: direct:production update-type: version-update:semver-patch ... Signed-off-by: dependabot[bot] <support@github.com>	2024-08-07 09:10:08 +00:00
Joel Kamp	8767951fa2	Merge pull request #114 from docker/dependabot/go_modules/google.golang.org/api-0.190.0 feat(deps): bump google.golang.org/api from 0.189.0 to 0.190.0	2024-08-06 10:15:47 -05:00
Joel Kamp	f18b5877d3	Merge branch 'main' into dependabot/go_modules/google.golang.org/api-0.190.0	2024-08-06 10:09:55 -05:00
Joel Kamp	93fd9daeb9	Merge pull request #116 from docker/dependabot/go_modules/github.com/open-policy-agent/opa-0.67.1 feat(deps): bump github.com/open-policy-agent/opa from 0.67.0 to 0.67.1	2024-08-06 10:08:32 -05:00
Joel Kamp	5df79de1c7	Merge branch 'main' into dependabot/go_modules/github.com/open-policy-agent/opa-0.67.1	2024-08-06 09:37:08 -05:00
Joel Kamp	5b5e43b07a	Merge pull request #113 from docker/fix-oci-layout-referrers fix: let OCI layouts use referrers attestations	2024-08-06 09:24:53 -05:00
dependabot[bot]	4c5135eb1b	feat(deps): bump github.com/open-policy-agent/opa from 0.67.0 to 0.67.1 Bumps [github.com/open-policy-agent/opa](https://github.com/open-policy-agent/opa) from 0.67.0 to 0.67.1. - [Release notes](https://github.com/open-policy-agent/opa/releases) - [Changelog](https://github.com/open-policy-agent/opa/blob/main/CHANGELOG.md) - [Commits](https://github.com/open-policy-agent/opa/compare/v0.67.0...v0.67.1) --- updated-dependencies: - dependency-name: github.com/open-policy-agent/opa dependency-type: direct:production update-type: version-update:semver-patch ... Signed-off-by: dependabot[bot] <support@github.com>	2024-08-06 09:01:35 +00:00
mrjoelkamp	0133423f0d	feat: add nil pointer test	2024-08-05 16:50:40 -05:00
mrjoelkamp	501b9b442d	feat: add CreateAttestationResolver tests	2024-08-05 16:31:39 -05:00
Joel Kamp	d84ed4821c	Merge branch 'main' into fix-oci-layout-referrers	2024-08-05 16:01:36 -05:00
Joel Kamp	c9e2ddd448	Merge pull request #115 from docker/chore--disable-codecov-patch-status chore: disable codecov patch status	2024-08-05 16:01:25 -05:00
mrjoelkamp	165241de42	chore: disable codecov patch status	2024-08-05 15:56:06 -05:00
mrjoelkamp	c7d17faf05	fix: layout attestation resolver	2024-08-05 15:32:24 -05:00
mrjoelkamp	58021646e3	feat: add oci layout test	2024-08-05 11:24:28 -05:00
mrjoelkamp	3e7a85e9b8	fix: nil pointer dereference	2024-08-05 11:24:05 -05:00
mrjoelkamp	bb7a9a257e	chore: remove duplicate code	2024-08-05 11:23:32 -05:00
mrjoelkamp	c690d1090c	chore: use prefix const	2024-08-05 11:22:49 -05:00
mrjoelkamp	1d1c258f9c	fix: referrers resolver only works for registry resolvers	2024-08-05 10:20:40 -05:00
mrjoelkamp	5d096e226f	refactor: fix import cycle for mock resolver	2024-08-05 10:19:50 -05:00
dependabot[bot]	7fc7ceaba0	feat(deps): bump google.golang.org/api from 0.189.0 to 0.190.0 Bumps [google.golang.org/api](https://github.com/googleapis/google-api-go-client) from 0.189.0 to 0.190.0. - [Release notes](https://github.com/googleapis/google-api-go-client/releases) - [Changelog](https://github.com/googleapis/google-api-go-client/blob/main/CHANGES.md) - [Commits](https://github.com/googleapis/google-api-go-client/compare/v0.189.0...v0.190.0) --- updated-dependencies: - dependency-name: google.golang.org/api dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com>	2024-08-02 08:34:34 +00:00
mrjoelkamp	78ec0b7666	fix: use referrers repo img spec and resolver	2024-08-01 15:24:35 -05:00
Joel Kamp	053f764b8f	Merge branch 'main' into fix-oci-layout-referrers	2024-08-01 13:48:53 -05:00
mrjoelkamp	ad3b8b9e49	fix: let OCI layouts use referrers attestations	2024-08-01 13:41:49 -05:00