fix: use a client pointing at Docker's TUF by default (#104)

`policy.Options` now contains the arguments to `tuf.Client`'s constructor rather than an actual Client. If these arguments are not provided, defaults pointing at Docker's TUF repo will be used. An actual TUF client can be passed in on the context (which is useful for testing). If this is not provided `attest.Verify` will create a TUF client using the options on `policy.Options`.

---------

Co-authored-by: Joel Kamp <joel.kamp@docker.com>

.github/workflows/test.yml

@@ -50,7 +50,7 @@ jobs:
           token: ${{ secrets.TC_CLOUD_TOKEN }}
       - name: go test including e2e
         if: matrix.os == 'ubuntu-latest' && github.actor != 'dependabot[bot]'
-        run: go test -tags=e2e -v ./... -coverprofile=coverage.out -covermode=atomic
+        run: go test -tags=e2e -v ./... -coverpkg=./... -coverprofile=coverage.out -covermode=atomic
       - name: go test excluding e2e
         if: matrix.os == 'macos-latest' || github.actor == 'dependabot[bot]'
         run: go test -v ./...

README.md

@@ -128,7 +128,10 @@ The input to the policy is an object with the following fields:
 
 - `digest` (string): the digest of the image being verified
 - `purl` (string): the package URL of the image being verified
-- `is_canonical` (bool): whether the image being verified was referenced by a 'canonical' name, i.e. one that contains a digest
+- `platform` (string): the platform of the image being verified
+- `normalized_name` (string): defaults are filled out. e.g. if the image is `alpine`, this would be `library/alpine`
+- `familiar_name` (string): short version of above (e.g. `alpine`)
+- `tag`: (string): tag of the image being verified (if present)
 
 ### Builtin Functions
 
@@ -345,7 +348,11 @@ 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"]

go.mod

@@ -4,7 +4,7 @@ go 1.22.5
 
 require (
 	github.com/Masterminds/semver/v3 v3.2.1
-	github.com/aws/aws-sdk-go-v2/config v1.27.27
+	github.com/aws/aws-sdk-go-v2/config v1.27.28
 	github.com/awslabs/amazon-ecr-credential-helper/ecr-login v0.0.0-20231024185945-8841054dbdb8
 	github.com/containerd/platforms v0.2.1
 	github.com/distribution/reference v0.6.0
@@ -24,7 +24,7 @@ require (
 	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 v0.191.0
+	google.golang.org/api v0.192.0
 	sigs.k8s.io/yaml v1.4.0
 )
 
@@ -33,7 +33,7 @@ replace github.com/google/go-containerregistry => github.com/docker/go-container
 
 require (
 	cloud.google.com/go v0.115.0 // indirect
-	cloud.google.com/go/auth v0.7.3 // indirect
+	cloud.google.com/go/auth v0.8.1 // 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 v1.1.12 // indirect
@@ -47,21 +47,21 @@ require (
 	github.com/ProtonMail/go-crypto v1.0.0 // indirect
 	github.com/agnivade/levenshtein v1.1.1 // indirect
 	github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2 // indirect
-	github.com/aws/aws-sdk-go-v2 v1.30.3 // indirect
+	github.com/aws/aws-sdk-go-v2 v1.30.4 // indirect
-	github.com/aws/aws-sdk-go-v2/credentials v1.17.27 // indirect
+	github.com/aws/aws-sdk-go-v2/credentials v1.17.28 // indirect
-	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.16.11 // indirect
+	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.16.12 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/configsources v1.3.15 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/configsources v1.3.16 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.6.15 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.6.16 // indirect
-	github.com/aws/aws-sdk-go-v2/internal/ini v1.8.0 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/ini v1.8.1 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ecr v1.29.1 // indirect
 	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/accept-encoding v1.11.4 // indirect
-	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.11.17 // indirect
+	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.11.18 // 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/sso v1.22.5 // indirect
-	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.4 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.5 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sts v1.30.3 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sts v1.30.4 // indirect
-	github.com/aws/smithy-go v1.20.3 // indirect
+	github.com/aws/smithy-go v1.20.4 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
 	github.com/blang/semver v3.5.1+incompatible // indirect
 	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
@@ -77,7 +77,7 @@ require (
 	github.com/digitorus/timestamp v0.0.0-20231217203849-220c5c2851b7 // 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 v27.1.1+incompatible // indirect
 	github.com/docker/docker-credential-helpers v0.8.1 // indirect
 	github.com/docker/go-connections v0.5.0 // indirect
 	github.com/docker/go-units v0.5.0 // indirect

go.sum

@@ -1,8 +1,8 @@
 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 v0.7.3 h1:98Vr+5jMaCZ5NZk6e/uBgf60phTk/XN84r8QEWB9yjY=
+cloud.google.com/go/auth v0.8.1 h1:QZW9FjC5lZzN864p13YxvAtGUlQ+KgRL+8Sg45Z6vxo=
-cloud.google.com/go/auth v0.7.3/go.mod h1:HJtWUx1P5eqjy/f6Iq5KeytNpbAcGolPhOgyop2LlzA=
+cloud.google.com/go/auth v0.8.1/go.mod h1:qGVp/Y3kDRSDZ5gFD/XPUfYQ9xW1iI7q8RIRoCyBbJc=
 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=
@@ -104,38 +104,38 @@ github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2 h1:DklsrG3d
 github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2/go.mod h1:WaHUgvxTVq04UNunO+XhnAqY/wQc+bxr74GqbsZ/Jqw=
 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 v1.30.4 h1:frhcagrVNrzmT95RJImMHgabt99vkXGslubDaDagTk8=
-github.com/aws/aws-sdk-go-v2 v1.30.3/go.mod h1:nIQjQVp5sfpQcTc9mPSr1B0PaWK5ByX9MOoDadSN4lc=
+github.com/aws/aws-sdk-go-v2 v1.30.4/go.mod h1:CT+ZPWXbYrci8chcARI3OmI/qgd+f6WtuLOoaIA8PR0=
-github.com/aws/aws-sdk-go-v2/config v1.27.27 h1:HdqgGt1OAP0HkEDDShEl0oSYa9ZZBSOmKpdpsDMdO90=
+github.com/aws/aws-sdk-go-v2/config v1.27.28 h1:OTxWGW/91C61QlneCtnD62NLb4W616/NM1jA8LhJqbg=
-github.com/aws/aws-sdk-go-v2/config v1.27.27/go.mod h1:MVYamCg76dFNINkZFu4n4RjDixhVr51HLj4ErWzrVwg=
+github.com/aws/aws-sdk-go-v2/config v1.27.28/go.mod h1:uzVRVtJSU5EFv6Fu82AoVFKozJi2ZCY6WRCXj06rbvs=
-github.com/aws/aws-sdk-go-v2/credentials v1.17.27 h1:2raNba6gr2IfA0eqqiP2XiQ0UVOpGPgDSi0I9iAP+UI=
+github.com/aws/aws-sdk-go-v2/credentials v1.17.28 h1:m8+AHY/ND8CMHJnPoH7PJIRakWGa4gbfbxuY9TGTUXM=
-github.com/aws/aws-sdk-go-v2/credentials v1.17.27/go.mod h1:gniiwbGahQByxan6YjQUMcW4Aov6bLC3m+evgcoN4r4=
+github.com/aws/aws-sdk-go-v2/credentials v1.17.28/go.mod h1:6TF7dSc78ehD1SL6KpRIPKMA1GyyWflIkjqg+qmf4+c=
-github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.16.11 h1:KreluoV8FZDEtI6Co2xuNk/UqI9iwMrOx/87PBNIKqw=
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.16.12 h1:yjwoSyDZF8Jth+mUk5lSPJCkMC0lMy6FaCD51jm6ayE=
-github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.16.11/go.mod h1:SeSUYBLsMYFoRvHE0Tjvn7kbxaUhl75CJi1sbfhMxkU=
+github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.16.12/go.mod h1:fuR57fAgMk7ot3WcNQfb6rSEn+SUffl7ri+aa8uKysI=
-github.com/aws/aws-sdk-go-v2/internal/configsources v1.3.15 h1:SoNJ4RlFEQEbtDcCEt+QG56MY4fm4W8rYirAmq+/DdU=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.3.16 h1:TNyt/+X43KJ9IJJMjKfa3bNTiZbUP7DeCxfbTROESwY=
-github.com/aws/aws-sdk-go-v2/internal/configsources v1.3.15/go.mod h1:U9ke74k1n2bf+RIgoX1SXFed1HLs51OgUSs+Ph0KJP8=
+github.com/aws/aws-sdk-go-v2/internal/configsources v1.3.16/go.mod h1:2DwJF39FlNAUiX5pAc0UNeiz16lK2t7IaFcm0LFHEgc=
-github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.6.15 h1:C6WHdGnTDIYETAm5iErQUiVNsclNx9qbJVPIt03B6bI=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.6.16 h1:jYfy8UPmd+6kJW5YhY0L1/KftReOGxI/4NtVSTh9O/I=
-github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.6.15/go.mod h1:ZQLZqhcu+JhSrA9/NXRm8SkDvsycE+JkV3WGY41e+IM=
+github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.6.16/go.mod h1:7ZfEPZxkW42Afq4uQB8H2E2e6ebh6mXTueEpYzjCzcs=
-github.com/aws/aws-sdk-go-v2/internal/ini v1.8.0 h1:hT8rVHwugYE2lEfdFE0QWVo81lF7jMrYJVDWI+f+VxU=
+github.com/aws/aws-sdk-go-v2/internal/ini v1.8.1 h1:VaRN3TlFdd6KxX1x3ILT5ynH6HvKgqdiXoTxAF4HQcQ=
-github.com/aws/aws-sdk-go-v2/internal/ini v1.8.0/go.mod h1:8tu/lYfQfFe6IGnaOdrpVgEL2IrrDOf6/m9RQum4NkY=
+github.com/aws/aws-sdk-go-v2/internal/ini v1.8.1/go.mod h1:FbtygfRFze9usAadmnGJNc8KsP346kEe+y2/oyhGAGc=
 github.com/aws/aws-sdk-go-v2/service/ecr v1.29.1 h1:ywNLJrn/Qn4enDsz/XnKlvpnLqvJxFGQV2BltWltbis=
 github.com/aws/aws-sdk-go-v2/service/ecr v1.29.1/go.mod h1:WadVIk+UrTvWuAsCp6BKGX4i2snurpz8mPWhJQnS7Dg=
 github.com/aws/aws-sdk-go-v2/service/ecrpublic v1.24.1 h1:Eq9i/mvOlGghiKe9NtsmeD9Wlwg8p4fbsqrMb3nWirM=
 github.com/aws/aws-sdk-go-v2/service/ecrpublic v1.24.1/go.mod h1:VtOgEoLEPV1YADuq+Z2XOK6/wKkGW2YK6DjChZ/GvDs=
-github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.11.3 h1:dT3MqvGhSoaIhRseqw2I0yH81l7wiR2vjs57O51EAm8=
+github.com/aws/aws-sdk-go-v2/service/internal/accept-encoding v1.11.4 h1:KypMCbLPPHEmf9DgMGw51jMj77VfGPAN2Kv4cfhlfgI=
-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/accept-encoding v1.11.4/go.mod h1:Vz1JQXliGcQktFTN/LN6uGppAIRoLBR2bMvIMP0gOjc=
-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 v1.11.18 h1:tJ5RnkHCiSH0jyd6gROjlJtNwov0eGYNz8s8nFcR0jQ=
-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/internal/presigned-url v1.11.18/go.mod h1:++NHzT+nAF7ZPrHPsA+ENvsXkOO8wEu+C6RXltAG4/c=
 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 v1.22.5 h1:zCsFCKvbj25i7p1u94imVoO447I/sFv8qq+lGJhRN0c=
-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/sso v1.22.5/go.mod h1:ZeDX1SnKsVlejeuz41GiajjZpRSWR7/42q/EyA/QEiM=
-github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.4 h1:yiwVzJW2ZxZTurVbYWA7QOrAaCYQR72t0wrSBfoesUE=
+github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.5 h1:SKvPgvdvmiTWoi0GAJ7AsJfOz3ngVkD/ERbs5pUnHNI=
-github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.4/go.mod h1:0oxfLkpz3rQ/CHlx5hB7H69YUpFiI1tql6Q6Ne+1bCw=
+github.com/aws/aws-sdk-go-v2/service/ssooidc v1.26.5/go.mod h1:20sz31hv/WsPa3HhU3hfrIet2kxM4Pe0r20eBZ20Tac=
-github.com/aws/aws-sdk-go-v2/service/sts v1.30.3 h1:ZsDKRLXGWHk8WdtyYMoGNO7bTudrvuKpDKgMVRlepGE=
+github.com/aws/aws-sdk-go-v2/service/sts v1.30.4 h1:iAckBT2OeEK/kBDyN/jDtpEExhjeeA/Im2q4X0rJZT8=
-github.com/aws/aws-sdk-go-v2/service/sts v1.30.3/go.mod h1:zwySh8fpFyXp9yOr/KVzxOl8SRqgf/IDw5aUt9UKFcQ=
+github.com/aws/aws-sdk-go-v2/service/sts v1.30.4/go.mod h1:vmSqFK+BVIwVpDAGZB3CoCXHzurt4qBE8lf+I/kRTh0=
-github.com/aws/smithy-go v1.20.3 h1:ryHwveWzPV5BIof6fyDvor6V3iUL7nTfiTKXHiW05nE=
+github.com/aws/smithy-go v1.20.4 h1:2HK1zBdPgRbjFOHlfeQZfpC4r72MOb9bZkiFwggKO+4=
-github.com/aws/smithy-go v1.20.3/go.mod h1:krry+ya/rV9RDcV/Q16kpu6ypI4K2czasz0NC3qS14E=
+github.com/aws/smithy-go v1.20.4/go.mod h1:irrKGvNn1InZwb2d7fkIRNucdfwR8R+Ts3wxYa/cJHg=
 github.com/awslabs/amazon-ecr-credential-helper/ecr-login v0.0.0-20231024185945-8841054dbdb8 h1:SoFYaT9UyGkR0+nogNyD/Lj+bsixB+SNuAS4ABlEs6M=
 github.com/awslabs/amazon-ecr-credential-helper/ecr-login v0.0.0-20231024185945-8841054dbdb8/go.mod h1:2JF49jcDOrLStIXN/j/K1EKRq8a8R2qRnlZA6/o/c7c=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
@@ -222,8 +222,8 @@ github.com/docker/cli v27.1.1+incompatible h1:goaZxOqs4QKxznZjjBWKONQci/MywhtRv2
 github.com/docker/cli v27.1.1+incompatible/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
 github.com/docker/distribution v2.8.3+incompatible h1:AtKxIZ36LoNK51+Z6RpzLpddBirtxJnzDrHLEKxTAYk=
 github.com/docker/distribution v2.8.3+incompatible/go.mod h1:J2gT2udsDAN96Uj4KfcMRqY0/ypR+oyYUYmja8H+y+w=
-github.com/docker/docker v27.1.0+incompatible h1:rEHVQc4GZ0MIQKifQPHSFGV/dVgaZafgRf8fCPtDYBs=
+github.com/docker/docker v27.1.1+incompatible h1:hO/M4MtV36kzKldqnA37IWhebRA+LnqqcqDja6kVaKY=
-github.com/docker/docker v27.1.0+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
+github.com/docker/docker v27.1.1+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/docker-credential-helpers v0.8.1 h1:j/eKUktUltBtMzKqmfLB0PAgqYyMHOp5vfsD1807oKo=
 github.com/docker/docker-credential-helpers v0.8.1/go.mod h1:P3ci7E3lwkZg6XiHdRKft1KckHiO9a2rNtyFbZ/ry9M=
 github.com/docker/go-connections v0.5.0 h1:USnMq7hx7gwdVZq1L49hLXaFtUdTADjXGp+uj1Br63c=
@@ -809,8 +809,8 @@ golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8T
 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 v0.191.0 h1:cJcF09Z+4HAB2t5qTQM1ZtfL/PemsLFkcFG67qq2afk=
+google.golang.org/api v0.192.0 h1:PljqpNAfZaaSpS+TnANfnNAXKdzHM/B9bKhwRlo7JP0=
-google.golang.org/api v0.191.0/go.mod h1:tD5dsFGxFza0hnQveGfVk9QQYKcfp+VzgRqyXFxE0+E=
+google.golang.org/api v0.192.0/go.mod h1:9VcphjvAxPKLmSxVSzPlSRXy/5ARMEw5bf58WoVXafQ=
 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=

internal/test/test.go

@@ -2,22 +2,13 @@ package test
 
 import (
 	"context"
-	"encoding/base64"
-	"encoding/json"
-	"fmt"
 	"os"
 	"path/filepath"
-	"strings"
 	"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"
 )
 
@@ -30,6 +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)
@@ -89,108 +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)
-}

pkg/attest/README.md

@@ -0,0 +1,2 @@
+## attest
+This package implements the top-level signing and verification methods.

pkg/attest/example_verify_test.go

@@ -6,24 +6,12 @@ import (
 	"os"
 	"path/filepath"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
 	"github.com/docker/attest/pkg/tuf"
 )
 
-func createTufClient(outputPath string) (*tuf.Client, error) {
-	// using oci tuf metadata and targets
-	metadataURI := "registry-1.docker.io/docker/tuf-metadata:latest"
-	targetsURI := "registry-1.docker.io/docker/tuf-targets"
-	// example using http tuf metadata and targets
-	// metadataURI := "https://docker.github.io/tuf-staging/metadata"
-	// targetsURI := "https://docker.github.io/tuf-staging/targets"
-
-	return tuf.NewClient(embed.RootStaging.Data, outputPath, metadataURI, targetsURI, tuf.NewMockVersionChecker())
-}
-
 func ExampleVerify_remote() {
 	// create a tuf client
 	home, err := os.UserHomeDir()
@@ -31,10 +19,7 @@ func ExampleVerify_remote() {
 		panic(err)
 	}
 	tufOutputPath := filepath.Join(home, ".docker", "tuf")
-	tufClient, err := createTufClient(tufOutputPath)
+	tufClientOpts := tuf.NewDockerDefaultClientOptions(tufOutputPath)
-	if err != nil {
-		panic(err)
-	}
 
 	// create a resolver for remote attestations
 	image := "registry-1.docker.io/library/notary:server"
@@ -42,10 +27,10 @@ func ExampleVerify_remote() {
 
 	// configure policy options
 	opts := &policy.Options{
-		TUFClient:       tufClient,
+		TUFClientOptions: tufClientOpts,
-		LocalTargetsDir: filepath.Join(home, ".docker", "policy"), // location to store policy files downloaded from TUF
+		LocalTargetsDir:  filepath.Join(home, ".docker", "policy"), // location to store policy files downloaded from TUF
-		LocalPolicyDir:  "",                                       // overrides TUF policy for local policy files if set
+		LocalPolicyDir:   "",                                       // overrides TUF policy for local policy files if set
-		PolicyID:        "",                                       // set to ignore policy mapping and select a policy by id
+		PolicyID:         "",                                       // set to ignore policy mapping and select a policy by id
 	}
 
 	src, err := oci.ParseImageSpec(image, oci.WithPlatform(platform))

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)
 			}

pkg/attest/sign_test.go

@@ -1,10 +1,6 @@
 package attest
 
 import (
-	"encoding/json"
-	"fmt"
-	"net/http/httptest"
-	"net/url"
 	"path/filepath"
 	"testing"
 
@@ -12,10 +8,7 @@ import (
 	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
-	"github.com/google/go-containerregistry/pkg/registry"
+	"github.com/docker/attest/pkg/tuf"
-	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"
 	v02 "github.com/in-toto/in-toto-golang/in_toto/slsa_provenance/v0.2"
 	"github.com/stretchr/testify/assert"
@@ -23,17 +16,19 @@ 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")
 	PassNoTLPolicyDir   = filepath.Join("..", "..", "test", "testdata", "local-policy-no-tl")
 	FailPolicyDir       = filepath.Join("..", "..", "test", "testdata", "local-policy-fail")
+	InputsPolicyDir     = filepath.Join("..", "..", "test", "testdata", "local-policy-inputs")
+	EmptyPolicyDir      = filepath.Join("..", "..", "test", "testdata", "local-policy-no-policies")
 	TestTempDir         = "attest-sign-test"
 )
 
 func TestSignVerifyOCILayout(t *testing.T) {
 	ctx, signer := test.Setup(t)
+	ctx = tuf.WithDownloader(ctx, tuf.NewMockTufClient(EmptyPolicyDir, test.CreateTempDir(t, "", "tuf-dest")))
 
 	testCases := []struct {
 		name                 string
@@ -42,8 +37,8 @@ func TestSignVerifyOCILayout(t *testing.T) {
 		expectedAttestations int
 		replace              bool
 	}{
-		{"signed replaced", UnsignedTestImage, 0, 4, true},
+		{"signed replaced", test.UnsignedTestImage, 0, 4, true},
-		{"without replace", UnsignedTestImage, 4, 4, false},
+		{"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},
@@ -70,10 +65,10 @@ func TestSignVerifyOCILayout(t *testing.T) {
 			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...)
 
@@ -83,150 +78,9 @@ 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 = oci.SaveReferrers(manifest, output)
-			require.NoError(t, err)
-		})
-	}
-}

pkg/attest/verify.go

@@ -3,6 +3,8 @@ package attest
 import (
 	"context"
 	"fmt"
+	"os"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -11,7 +13,7 @@ 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"
+	"github.com/docker/attest/pkg/tuf"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 )
 
@@ -21,13 +23,20 @@ func Verify(ctx context.Context, src *oci.ImageSpec, opts *policy.Options) (resu
 	if err != nil {
 		return nil, fmt.Errorf("failed to create image details resolver: %w", err)
 	}
-	if opts.AttestationStyle == "" {
+	err = populateDefaultOptions(opts)
-		opts.AttestationStyle = config.AttestationStyleReferrers
+	if err != nil {
+		return nil, err
 	}
-	if opts.ReferrersRepo != "" && opts.AttestationStyle != config.AttestationStyleReferrers {
+
-		return nil, fmt.Errorf("referrers repo specified but attestation source not set to referrers")
+	tufClient, ok := tuf.GetDownloader(ctx)
+	if !ok {
+		tufClient, err = tuf.NewClient(opts.TUFClientOptions)
+		if err != nil {
+			return nil, fmt.Errorf("failed to create TUF client: %w", err)
+		}
 	}
-	pctx, err := policy.ResolvePolicy(ctx, detailsResolver, opts)
+
+	pctx, err := policy.ResolvePolicy(ctx, tufClient, detailsResolver, opts)
 	if err != nil {
 		return nil, fmt.Errorf("failed to resolve policy: %w", err)
 	}
@@ -61,6 +70,36 @@ func Verify(ctx context.Context, src *oci.ImageSpec, opts *policy.Options) (resu
 	return result, nil
 }
 
+func populateDefaultOptions(opts *policy.Options) (err error) {
+	if opts.LocalTargetsDir == "" {
+		opts.LocalTargetsDir, err = defaultLocalTargetsDir()
+		if err != nil {
+			return err
+		}
+	}
+
+	if opts.TUFClientOptions == nil {
+		opts.TUFClientOptions = tuf.NewDockerDefaultClientOptions(opts.LocalTargetsDir)
+	}
+
+	if opts.AttestationStyle == "" {
+		opts.AttestationStyle = config.AttestationStyleReferrers
+	}
+	if opts.ReferrersRepo != "" && opts.AttestationStyle != config.AttestationStyleReferrers {
+		return fmt.Errorf("referrers repo specified but attestation source not set to referrers")
+	}
+
+	return nil
+}
+
+func defaultLocalTargetsDir() (string, error) {
+	homeDir, err := os.UserHomeDir()
+	if err != nil {
+		return "", fmt.Errorf("failed to get user home directory: %w", err)
+	}
+	return filepath.Join(homeDir, ".docker", "tuf"), nil
+}
+
 func toVerificationResult(p *policy.Policy, input *policy.Input, result *policy.Result) (*VerificationResult, error) {
 	dgst, err := oci.SplitDigest(input.Digest)
 	if err != nil {
@@ -87,6 +126,8 @@ 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 +145,7 @@ 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 +153,7 @@ 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)
@@ -139,14 +180,34 @@ func VerifyAttestations(ctx context.Context, resolver oci.AttestationResolver, p
 		name = strings.Replace(name, oldName, pctx.ResolvedName, 1)
 	}
 
-	purl, canonical, err := oci.RefToPURL(name, platform)
+	ref, err := reference.ParseNormalizedNamed(name)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse ref %q: %w", ref, err)
+	}
+	purl, canonical, err := oci.RefToPURL(ref, platform)
 	if err != nil {
 		return nil, fmt.Errorf("failed to convert ref to purl: %w", err)
 	}
+	var tag string
+	if !canonical {
+		// unlike the function name indicates, this adds latest if no tag is present
+		ref = reference.TagNameOnly(ref)
+	}
+
+	if tagged, ok := ref.(reference.Tagged); ok {
+		tag = tagged.Tag()
+	}
 	input := &policy.Input{
-		Digest:      digest,
+		Digest:         digest,
-		PURL:        purl,
+		PURL:           purl,
-		IsCanonical: canonical,
+		Platform:       platform.String(),
+		Domain:         reference.Domain(ref),
+		NormalizedName: reference.Path(ref),
+		FamiliarName:   reference.FamiliarName(ref),
+	}
+	// rego has null strings
+	if tag != "" {
+		input.Tag = tag
 	}
 
 	evaluator, err := policy.GetPolicyEvaluator(ctx)
@@ -164,13 +225,3 @@ 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
-}

pkg/attest/verify_test.go

@@ -8,11 +8,13 @@ import (
 	"path/filepath"
 	"testing"
 
+	"github.com/distribution/reference"
 	"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"
+	"github.com/docker/attest/pkg/tuf"
 	intoto "github.com/in-toto/in-toto-golang/in_toto"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -31,7 +33,7 @@ func TestVerifyAttestations(t *testing.T) {
 	env := new(attestation.Envelope)
 	err = json.Unmarshal(ex, env)
 	assert.NoError(t, err)
-	resolver := &oci.MockResolver{
+	resolver := &attestation.MockResolver{
 		Envs: []*attestation.Envelope{env},
 	}
 
@@ -47,7 +49,7 @@ 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
 				},
 			}
@@ -68,11 +70,12 @@ func TestVerifyAttestations(t *testing.T) {
 func TestVSA(t *testing.T) {
 	ctx, signer := test.Setup(t)
 	ctx = policy.WithPolicyEvaluator(ctx, policy.NewRegoEvaluator(true))
+	ctx = tuf.WithDownloader(ctx, tuf.NewMockTufClient(EmptyPolicyDir, test.CreateTempDir(t, "", "tuf-dest")))
 	// setup an image with signed attestations
 	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)
@@ -98,7 +101,7 @@ func TestVSA(t *testing.T) {
 
 	if assert.NotNil(t, results.Input) {
 		assert.Equal(t, "sha256:da8b190665956ea07890a0273e2a9c96bfe291662f08e2860e868eef69c34620", results.Input.Digest)
-		assert.False(t, results.Input.IsCanonical)
+		assert.NotNil(t, results.Input.Tag)
 	}
 
 	assert.Equal(t, intoto.StatementInTotoV01, results.VSA.Type)
@@ -112,17 +115,20 @@ 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) {
 	ctx, signer := test.Setup(t)
 	ctx = policy.WithPolicyEvaluator(ctx, policy.NewRegoEvaluator(true))
+	ctx = tuf.WithDownloader(ctx, tuf.NewMockTufClient(EmptyPolicyDir, test.CreateTempDir(t, "", "tuf-dest")))
 	// setup an image with signed attestations
 	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)
@@ -162,30 +168,35 @@ 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) {
 	ctx, signer := test.Setup(t)
 	ctx = policy.WithPolicyEvaluator(ctx, policy.NewRegoEvaluator(true))
+	ctx = tuf.WithDownloader(ctx, tuf.NewMockTufClient(EmptyPolicyDir, test.CreateTempDir(t, "", "tuf-dest")))
 	// setup an image with signed attestations
 	outputLayout := test.CreateTempDir(t, "", TestTempDir)
 
 	testCases := []struct {
-		name        string
+		name      string
-		signTL      bool
+		signTL    bool
-		policyDir   string
+		policyDir string
-		imageName   string
+		imageName string
-		expectError bool
+
+		expectedNonSuccess Outcome
 	}{
 		{name: "happy path", signTL: true, policyDir: PassNoTLPolicyDir},
 		{name: "sign tl, verify no tl", signTL: true, policyDir: PassPolicyDir},
 		{name: "no tl", signTL: false, policyDir: PassPolicyDir},
 		{name: "mirror", signTL: true, policyDir: PassMirrorPolicyDir, imageName: "mirror.org/library/test-image:test"},
-		{name: "mirror no match", signTL: true, policyDir: PassMirrorPolicyDir, imageName: "incorrect.org/library/test-image:test", expectError: true},
+		{name: "mirror no match", signTL: true, policyDir: PassMirrorPolicyDir, imageName: "incorrect.org/library/test-image:test", expectedNonSuccess: OutcomeNoPolicy},
+		{name: "verify inputs", signTL: false, policyDir: InputsPolicyDir},
 	}
 
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
+	attIdx, err := oci.IndexFromPath(test.UnsignedTestImage)
 	assert.NoError(t, err)
 
 	for _, tc := range testCases {
@@ -214,17 +225,84 @@ func TestSignVerify(t *testing.T) {
 				LocalPolicyDir: tc.policyDir,
 			}
 			results, err := Verify(ctx, spec, policyOpts)
-			if tc.expectError {
+			require.NoError(t, err)
-				require.Error(t, err)
+			if tc.expectedNonSuccess != "" {
+				assert.Equal(t, tc.expectedNonSuccess, results.Outcome)
 				return
 			}
-			require.NoError(t, err)
 			assert.Equal(t, OutcomeSuccess, results.Outcome)
 			platform, err := oci.ParsePlatform(LinuxAMD64)
 			require.NoError(t, err)
-			expectedPURL, _, err := oci.RefToPURL(attIdx.Name, platform)
+
+			ref, err := reference.ParseNormalizedNamed(attIdx.Name)
+			require.NoError(t, err)
+			expectedPURL, _, err := oci.RefToPURL(ref, platform)
 			require.NoError(t, err)
 			assert.Equal(t, expectedPURL, results.Input.PURL)
 		})
 	}
 }
+
+func TestDefaultOptions(t *testing.T) {
+	testCases := []struct {
+		name             string
+		tufOpts          *tuf.ClientOptions
+		localTargetsDir  string
+		attestationStyle config.AttestationStyle
+		referrersRepo    string
+		expectedError    string
+	}{
+		{name: "empty"},
+		{name: "tufClient provided", tufOpts: &tuf.ClientOptions{MetadataSource: "a", TargetsSource: "b"}},
+		{name: "localTargetsDir provided", localTargetsDir: test.CreateTempDir(t, "", TestTempDir)},
+		{name: "attestationStyle provided", attestationStyle: config.AttestationStyleAttached},
+		{name: "referrersRepo provided", referrersRepo: "referrers"},
+		{name: "referrersRepo provided with attached", referrersRepo: "referrers", attestationStyle: config.AttestationStyleAttached, expectedError: "referrers repo specified but attestation source not set to referrers"},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			defaultTargets, err := defaultLocalTargetsDir()
+			require.NoError(t, err)
+
+			opts := &policy.Options{
+				TUFClientOptions: tc.tufOpts,
+				LocalTargetsDir:  tc.localTargetsDir,
+				AttestationStyle: tc.attestationStyle,
+				ReferrersRepo:    tc.referrersRepo,
+			}
+
+			err = populateDefaultOptions(opts)
+			if tc.expectedError != "" {
+				require.Error(t, err)
+				assert.Equal(t, tc.expectedError, err.Error())
+				return
+			}
+
+			require.NoError(t, err)
+
+			if tc.localTargetsDir != "" {
+				assert.Equal(t, tc.localTargetsDir, opts.LocalTargetsDir)
+			} else {
+				assert.Equal(t, defaultTargets, opts.LocalTargetsDir)
+			}
+
+			if tc.attestationStyle != "" {
+				assert.Equal(t, tc.attestationStyle, opts.AttestationStyle)
+			} else {
+				assert.Equal(t, config.AttestationStyleReferrers, opts.AttestationStyle)
+			}
+
+			if tc.tufOpts != nil {
+				assert.Equal(t, tc.tufOpts, opts.TUFClientOptions)
+			} else {
+				assert.NotNil(t, opts.TUFClientOptions)
+			}
+
+			if tc.referrersRepo != "" {
+				assert.Equal(t, tc.referrersRepo, opts.ReferrersRepo)
+			} else {
+				assert.Empty(t, opts.ReferrersRepo)
+			}
+		})
+	}
+}

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.

pkg/attestation/attestation.go

@@ -1,14 +1,17 @@
 package attestation
 
 import (
-	"bytes"
 	"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"
@@ -18,8 +21,19 @@ import (
 	"github.com/secure-systems-lab/go-securesystemslib/dsse"
 )
 
-// GetAttestationManifestsFromIndex extracts all attestation manifests from an index.
+// NewManifest creates a new attestation manifest from a descriptor.
-func GetAttestationManifestsFromIndex(index v1.ImageIndex) ([]*Manifest, error) {
+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)
@@ -42,7 +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)
 			}
@@ -57,8 +71,8 @@ func GetAttestationManifestsFromIndex(index v1.ImageIndex) ([]*Manifest, error)
 	return attestationManifests, nil
 }
 
-// GetAttestationsFromImage extracts all attestation layers from an image.
+// LayersFromImage extracts all attestation layers from an image.
-func GetAttestationsFromImage(image v1.Image) ([]*Layer, error) {
+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)
@@ -94,7 +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)
@@ -105,7 +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)
 	}
@@ -128,7 +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)
@@ -140,12 +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)
 	}
@@ -170,7 +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)
 		}
@@ -204,7 +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)
@@ -229,7 +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)
 	}
@@ -241,7 +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)
 		}
@@ -250,8 +264,8 @@ func (manifest *Manifest) BuildReferringArtifacts() ([]v1.Image, error) {
 	return images, nil
 }
 
-// build an image containing only layers.
+// build an image containing only layers provided.
-func buildImage(layers []*Layer, manifest *v1.Descriptor, subject *v1.Descriptor, opts *ManifestImageOptions) (v1.Image, error) {
+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 {
@@ -296,46 +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 {
+func ExtractEnvelopes(manifest *Manifest, predicateType string) ([]*Envelope, error) {
-	v1.Image
+	var envs []*Envelope
-}
+	dsseMediaType, err := DSSEMediaType(predicateType)
-
-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)
+		return nil, fmt.Errorf("failed to get DSSE media type for predicate '%s': %w", predicateType, err)
 	}
-	mf.Config = v1.Descriptor{
+	for _, attestationLayer := range manifest.OriginalLayers {
-		MediaType: "application/vnd.oci.empty.v1+json",
+		mt, err := attestationLayer.Layer.MediaType()
-		Size:      2,
+		if err != nil {
-		Digest:    v1.Hash{Algorithm: "sha256", Hex: "44136fa355b3678a1146ad16f7e8649e94fb4fc21fe77e8310c060f61caaff8a"},
+			return nil, fmt.Errorf("failed to get layer media type: %w", err)
-		Data:      []byte("{}"),
+		}
+		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) {
+func ExtractStatementsFromIndex(idx v1.ImageIndex, mediaType string) ([]*AnnotatedStatement, error) {
-	mf, err := i.Manifest()
+	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 (i *EmptyConfigImage) Digest() (v1.Hash, error) {
+func ExtractAnnotatedStatements(path string, mediaType string) ([]*AnnotatedStatement, error) {
-	mb, err := i.RawManifest()
+	idx, err := layout.ImageIndexFromPath(path)
 	if err != nil {
-		return v1.Hash{}, err
+		return nil, fmt.Errorf("failed to load image index: %w", err)
 	}
-	digest, _, err := v1.SHA256(bytes.NewReader(mb))
+
-	return digest, 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)
 }

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))
 }

pkg/attestation/example_attestation_manifest_test.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"time"
 
-	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/signerverifier"
@@ -62,13 +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)
 	}
@@ -79,7 +78,11 @@ func ExampleManifest() {
 	}
 
 	// save the manifest to the registry as a referrers artifact
-	err = oci.SaveReferrers(manifest, output)
+	artifacts, err := manifest.BuildReferringArtifacts()
+	if err != nil {
+		panic(err)
+	}
+	err = oci.SaveImagesNoTag(artifacts, output)
 	if err != nil {
 		panic(err)
 	}

pkg/attestation/layout.go

@@ -1,36 +1,35 @@
-package oci
+package attestation
 
 import (
 	"context"
 	"encoding/json"
 	"fmt"
 
-	"github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
-	att "github.com/docker/attest/pkg/attestation"
 	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
+	*Manifest
-	*ImageSpec
+	*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) {
+func (r *LayoutResolver) Attestations(_ context.Context, predicateType string) ([]*Envelope, error) {
-	var envs []*att.Envelope
+	var envs []*Envelope
-	dsseMediaType, err := attestation.DSSEMediaType(predicateType)
+	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
@@ -120,11 +119,11 @@ func attestationManifestFromOCILayout(path string, platform *v1.Platform) (*atte
 	}
 	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
 		}
 
@@ -132,11 +131,11 @@ 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:        idxDescriptor.Annotations["org.opencontainers.image.ref.name"],

pkg/attestation/layout_test.go

@@ -1,4 +1,4 @@
-package oci_test
+package attestation_test
 
 import (
 	"strings"
@@ -24,7 +24,7 @@ func TestAttestationFromOCILayout(t *testing.T) {
 	}
 
 	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)

pkg/attestation/mock.go

@@ -1,17 +1,17 @@
-package oci
+package attestation
 
 import (
 	"context"
 
-	"github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 )
 
 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
 }
 
@@ -32,7 +32,7 @@ func (r MockResolver) ImageDescriptor(_ context.Context) (*v1.Descriptor, error)
 }
 
 func (r MockResolver) ImagePlatform(_ context.Context) (*v1.Platform, error) {
-	return ParsePlatform("linux/amd64")
+	return oci.ParsePlatform("linux/amd64")
 }
 
 type MockRegistryResolver struct {

pkg/attestation/referrers.go

@@ -1,22 +1,21 @@
-package oci
+package attestation
 
 import (
 	"context"
 	"fmt"
 	"strings"
 
-	"github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/oci"
-	att "github.com/docker/attest/pkg/attestation"
 	"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,
 	}
@@ -36,8 +35,8 @@ func WithReferrersRepo(repo string) func(*ReferrersResolver) error {
 	}
 }
 
-func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateType string) ([]*attestation.Manifest, error) {
+func (r *ReferrersResolver) resolveAttestations(ctx context.Context, predicateType string) ([]*Manifest, error) {
-	dsseMediaType, err := attestation.DSSEMediaType(predicateType)
+	dsseMediaType, err := DSSEMediaType(predicateType)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get DSSE media type for predicate '%s': %w", predicateType, err)
 	}
@@ -54,19 +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", strings.TrimPrefix(r.referrersRepo, RegistryPrefix), 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 {
@@ -76,16 +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)
 		}
@@ -99,7 +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,
@@ -110,12 +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 {

pkg/attestation/referrers_test.go

@@ -8,34 +8,34 @@ import (
 	"testing"
 
 	"github.com/docker/attest/internal/test"
-	"github.com/docker/attest/internal/util"
 	"github.com/docker/attest/pkg/attest"
 	"github.com/docker/attest/pkg/attestation"
 	"github.com/docker/attest/pkg/config"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/policy"
+	"github.com/docker/attest/pkg/tuf"
 	"github.com/google/go-containerregistry/pkg/name"
 	"github.com/google/go-containerregistry/pkg/registry"
-	"github.com/google/go-containerregistry/pkg/v1/empty"
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )
 
 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")
 	LocalPolicyAttached = filepath.Join("..", "..", "test", "testdata", "local-policy-attached")
 	PassNoTLPolicyDir   = filepath.Join("..", "..", "test", "testdata", "local-policy-no-tl")
 	FailPolicyDir       = filepath.Join("..", "..", "test", "testdata", "local-policy-fail")
+	EmptyTUFDir         = filepath.Join("..", "..", "test", "testdata", "local-policy-no-policies")
 	TestTempDir         = "attest-sign-test"
 )
 
 func TestAttestationReferenceTypes(t *testing.T) {
 	ctx, signer := test.Setup(t)
 	ctx = policy.WithPolicyEvaluator(ctx, policy.NewRegoEvaluator(true))
+	ctx = tuf.WithDownloader(ctx, tuf.NewMockTufClient(EmptyTUFDir, test.CreateTempDir(t, "", "tuf-dest")))
 	platforms := []string{"linux/amd64", "linux/arm64"}
 	for _, tc := range []struct {
 		name              string
@@ -94,7 +94,7 @@ 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)
@@ -120,7 +120,9 @@ func TestAttestationReferenceTypes(t *testing.T) {
 			output, err := oci.ParseImageSpec(outputRepo)
 			require.NoError(t, err)
 			for _, attIdx := range signedManifests {
-				err = oci.SaveReferrers(attIdx, []*oci.ImageSpec{output})
+				images, err := attIdx.BuildReferringArtifacts()
+				require.NoError(t, err)
+				err = oci.SaveImagesNoTag(images, []*oci.ImageSpec{output})
 				require.NoError(t, err)
 			}
 
@@ -183,6 +185,7 @@ func TestAttestationReferenceTypes(t *testing.T) {
 
 func TestReferencesInDifferentRepo(t *testing.T) {
 	ctx, signer := test.Setup(t)
+	ctx = tuf.WithDownloader(ctx, tuf.NewMockTufClient(EmptyTUFDir, test.CreateTempDir(t, "", "tuf-dest")))
 	repoName := "repo"
 	for _, tc := range []struct {
 		name      string
@@ -213,7 +216,7 @@ 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)
@@ -226,7 +229,7 @@ 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 = oci.PushImageToRegistry(image, fmt.Sprintf("%s/%s:tag-does-not-matter", refServerURL.Host, repoName))
 			require.NoError(t, err)
@@ -239,7 +242,7 @@ 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)
@@ -294,7 +297,7 @@ 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)
@@ -327,14 +330,3 @@ func TestCorrectArtifactTypeInTagFallback(t *testing.T) {
 		}
 	}
 }
-
-func TestEmptyConfigImageDigest(t *testing.T) {
-	empty := empty.Image
-	img := attestation.EmptyConfigImage{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)
-}

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
+}

pkg/attestation/registry_test.go

@@ -1,4 +1,4 @@
-package oci_test
+package attestation_test
 
 import (
 	"fmt"
@@ -25,7 +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)

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)
+}

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)
+		})
+	}
+}

pkg/attestation/types.go

@@ -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 {

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 {

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)
 	}

pkg/mirror/README.md

@@ -0,0 +1,2 @@
+## mirror
+This package contains components to mirror TUF metadata and targets to OCI.

pkg/mirror/example_mirror_test.go

@@ -6,7 +6,6 @@ import (
 	"path/filepath"
 	"strings"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/pkg/mirror"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/docker/attest/pkg/tuf"
@@ -30,7 +29,7 @@ func ExampleNewTUFMirror() {
 	// configure TUF mirror
 	metadataURI := "https://docker.github.io/tuf-staging/metadata"
 	targetsURI := "https://docker.github.io/tuf-staging/targets"
-	m, err := mirror.NewTUFMirror(embed.RootStaging.Data, tufOutputPath, metadataURI, targetsURI, tuf.NewMockVersionChecker())
+	m, err := mirror.NewTUFMirror(tuf.DockerTUFRootStaging.Data, tufOutputPath, metadataURI, targetsURI, tuf.NewMockVersionChecker())
 	if err != nil {
 		panic(err)
 	}

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
 }

pkg/mirror/metadata_test.go

@@ -9,22 +9,26 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/tuf"
 	"github.com/stretchr/testify/assert"
 	"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(tuf.DockerTUFRootDev.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 +43,10 @@ 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(tuf.DockerTUFRootDev.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 +82,7 @@ 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(tuf.DockerTUFRootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)
 
 	delegations, err := m.GetDelegatedMetadataMirrors()

pkg/mirror/mirror.go

@@ -3,15 +3,14 @@ package mirror
 import (
 	"fmt"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/pkg/tuf"
 )
 
 func NewTUFMirror(root []byte, tufPath, metadataURL, targetsURL string, versionChecker tuf.VersionChecker) (*TUFMirror, error) {
 	if root == nil {
-		root = embed.RootDefault.Data
+		root = tuf.DockerTUFRootDefault.Data
 	}
-	tufClient, err := tuf.NewClient(root, tufPath, metadataURL, targetsURL, versionChecker)
+	tufClient, err := tuf.NewClient(&tuf.ClientOptions{InitialRoot: root, Path: tufPath, MetadataSource: metadataURL, TargetsSource: targetsURL, VersionChecker: versionChecker})
 	if err != nil {
 		return nil, fmt.Errorf("failed to create TUF client: %w", err)
 	}

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),

pkg/mirror/targets_test.go

@@ -8,7 +8,6 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/internal/test"
 	"github.com/docker/attest/pkg/tuf"
 	"github.com/stretchr/testify/assert"
@@ -27,7 +26,7 @@ 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(tuf.DockerTUFRootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)
 
 	targets, err := m.GetTUFTargetMirrors()
@@ -61,7 +60,7 @@ 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(tuf.DockerTUFRootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)
 
 	targets, err := tm.TUFClient.LoadDelegatedTargets("test-role", "targets")
@@ -74,7 +73,7 @@ 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(tuf.DockerTUFRootDev.Data, path, server.URL+metadataPath, server.URL+targetsPath, tuf.NewMockVersionChecker())
 	assert.NoError(t, err)
 
 	mirrors, err := m.GetDelegatedTargetMirrors()

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
 }
 

pkg/oci/README.md

@@ -0,0 +1,2 @@
+## oci
+This package is for generic OCI components. For attestation specific components see the `attestation` package.

pkg/oci/authn_test.go

@@ -1,19 +1,17 @@
 //go:build e2e
 
-package mirror_test
+package oci_test
 
 import (
-	"path/filepath"
 	"testing"
 
+	"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(test.UnsignedTestImage)
-
-	attIdx, err := oci.IndexFromPath(UnsignedTestImage)
 	require.NoError(t, err)
 	// test cases for ecr, gcr and dockerhub
 	testCases := []struct {

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) {
+func ImageDescriptor(ix *v1.IndexManifest, platform *v1.Platform) (*v1.Descriptor, 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) {
 	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) {
@@ -84,24 +52,8 @@ 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) {
+func RefToPURL(named reference.Named, platform *v1.Platform) (string, bool, 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)
-	if err != nil {
-		return "", false, fmt.Errorf("failed to parse ref %q: %w", ref, err)
-	}
 	var qualifiers []packageurl.Qualifier
 
 	if canonical, ok := named.(reference.Canonical); ok {
@@ -150,7 +102,7 @@ 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 +114,7 @@ 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
 	}

pkg/oci/oci_test.go

@@ -1,56 +1,65 @@
-package oci
+package oci_test
 
 import (
-	"path/filepath"
 	"testing"
 
+	"github.com/distribution/reference"
+	"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"
 	"github.com/stretchr/testify/require"
 )
 
-var UnsignedTestImage = filepath.Join("..", "..", "test", "testdata", "unsigned-test-image")
-
 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)
+	ref, err := reference.ParseNormalizedNamed("alpine")
+	require.NoError(t, err)
+	purl, canonical, err := oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@latest?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("alpine:123")
-	purl, canonical, err = RefToPURL("alpine:123", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("google/alpine:123")
-	purl, canonical, err = RefToPURL("google/alpine:123", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/google/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("library/alpine:123")
-	purl, canonical, err = RefToPURL("library/alpine:123", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("docker.io/library/alpine:123")
-	purl, canonical, err = RefToPURL("docker.io/library/alpine:123", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("localhost:5001/library/alpine:123")
-	purl, canonical, err = RefToPURL("localhost:5001/library/alpine:123", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/localhost%3A5001/library/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("localhost:5001/alpine:123")
-	purl, canonical, err = RefToPURL("localhost:5001/alpine:123", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/localhost%3A5001/alpine@123?platform=arm64%2Flinux", purl)
 	assert.False(t, canonical)
-
+	ref, err = reference.ParseNormalizedNamed("localhost:5001/alpine@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b")
-	purl, canonical, err = RefToPURL("localhost:5001/alpine@sha256:c5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b", arm)
+	require.NoError(t, err)
+	purl, canonical, err = oci.RefToPURL(ref, arm)
 	assert.NoError(t, err)
 	assert.Equal(t, "pkg:docker/localhost%3A5001/alpine?digest=sha256%3Ac5b1261d6d3e43071626931fc004f70149baeba2c8ec672bd4f27761f8e1ad6b&platform=arm64%2Flinux", purl)
 	assert.True(t, canonical)
@@ -58,7 +67,7 @@ func TestRefToPurl(t *testing.T) {
 
 // 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 +81,16 @@ 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 +104,14 @@ 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: RegistryPrefix + "image:tag", expected: RegistryPrefix + "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: RegistryPrefix + "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: RegistryPrefix + "index.docker.io/library/image"},
+		{name: oci.RegistryPrefix + "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: oci.RegistryPrefix + "index.docker.io/library/image"},
-		{name: RegistryPrefix + "127.0.0.1:36555/repo:latest", expected: RegistryPrefix + "127.0.0.1:36555/repo"},
+		{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 +125,11 @@ 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: RegistryPrefix + "image:tag", expected: RegistryPrefix + "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: LocalPrefix + "foobar", expected: LocalPrefix + "foobar"},
+		{name: oci.LocalPrefix + "foobar", expected: oci.LocalPrefix + "foobar"},
-		{name: RegistryPrefix + "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: RegistryPrefix + "index.docker.io/library/image:sha256-digest.att"},
+		{name: oci.RegistryPrefix + "image@sha256:166710df254975d4a6c4c407c315951c22753dcaa829e020a3fd5d18fff70dd2", expected: oci.RegistryPrefix + "index.docker.io/library/image:sha256-digest.att"},
-		{name: RegistryPrefix + "127.0.0.1:36555/repo:latest", expected: RegistryPrefix + "127.0.0.1:36555/repo: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 +138,7 @@ 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)
 		})

pkg/oci/output.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"os"
 
-	"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/empty"
@@ -13,6 +12,7 @@ import (
 	"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 {
@@ -23,6 +23,7 @@ func PushImageToRegistry(image v1.Image, imageName string) error {
 	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)
@@ -34,6 +35,7 @@ func PushIndexToRegistry(index v1.ImageIndex, imageName string) error {
 	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)
@@ -48,6 +50,7 @@ func SaveImageAsOCILayout(image v1.Image, path string) error {
 	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)
@@ -62,6 +65,7 @@ func SaveIndexAsOCILayout(image v1.ImageIndex, path string) error {
 	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 {
@@ -89,6 +93,7 @@ func SaveIndex(outputs []*ImageSpec, index v1.ImageIndex, indexName string) erro
 	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)
@@ -113,26 +118,23 @@ func SaveImage(output *ImageSpec, image v1.Image, imageName string) error {
 	return nil
 }
 
-func SaveReferrers(manifest *attestation.Manifest, outputs []*ImageSpec) error {
+// 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 for referrers not supported
+		// OCI layout output not supported
 		if output.Type == OCI {
 			continue
 		}
-		images, err := manifest.BuildReferringArtifacts()
-		if err != nil {
-			return fmt.Errorf("failed to build image: %w", err)
-		}
 		for _, image := range images {
 			digest, err := image.Digest()
 			if err != nil {
-				return fmt.Errorf("failed to get attestation image digest: %w", err)
+				return fmt.Errorf("failed to get image digest: %w", err)
 			}
-			attOut, err := ReplaceDigestInSpec(output, digest)
+			spec, err := ReplaceDigestInSpec(output, digest)
 			if err != nil {
-				return fmt.Errorf("failed to create attestation image spec: %w", err)
+				return fmt.Errorf("failed to create image spec: %w", err)
 			}
-			err = PushImageToRegistry(image, attOut.Identifier)
+			err = PushImageToRegistry(image, spec.Identifier)
 			if err != nil {
 				return fmt.Errorf("failed to push image: %w", err)
 			}

pkg/oci/output_test.go

@@ -4,11 +4,9 @@ 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())
@@ -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 = oci.SaveReferrers(manifest, output)
+	artifacts, err := manifest.BuildReferringArtifacts()
+	require.NoError(t, err)
+	err = oci.SaveImagesNoTag(artifacts, output)
 	require.NoError(t, err)
 
-	reg := &oci.MockRegistryResolver{
+	reg := &attestation.MockRegistryResolver{
 		Subject:      subject,
-		MockResolver: &oci.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)

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
-}

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)

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
+}

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)
+}

pkg/policy/README.md

@@ -0,0 +1,2 @@
+## policy
+This package is for attestation policy mapping and evaluation.

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)
 }

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
 		},
 	}

pkg/policy/policy.go

@@ -8,14 +8,19 @@ 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"
+	"github.com/docker/attest/pkg/tuf"
 )
 
 func resolveLocalPolicy(opts *Options, mapping *config.PolicyMapping, imageName string, matchedName string) (*Policy, error) {
 	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 +33,24 @@ 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
@@ -39,22 +58,38 @@ func resolveLocalPolicy(opts *Options, mapping *config.PolicyMapping, imageName
 	return policy, nil
 }
 
-func resolveTUFPolicy(opts *Options, mapping *config.PolicyMapping, imageName string, matchedName string) (*Policy, error) {
+func resolveTUFPolicy(opts *Options, tufClient tuf.Downloader, 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 := 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
@@ -120,7 +155,7 @@ func findPolicyMatchImpl(imageName string, mappings *config.PolicyMappings, matc
 	return &policyMatch{matchType: matchTypeNoMatch, matchedName: imageName}, nil
 }
 
-func resolvePolicyByID(opts *Options) (*Policy, error) {
+func resolvePolicyByID(opts *Options, tufClient tuf.Downloader) (*Policy, error) {
 	if opts.PolicyID != "" {
 		localMappings, err := config.LoadLocalMappings(opts.LocalPolicyDir)
 		if err != nil {
@@ -134,21 +169,21 @@ func resolvePolicyByID(opts *Options) (*Policy, error) {
 		}
 
 		// must check tuf
-		tufMappings, err := config.LoadTUFMappings(opts.TUFClient, opts.LocalTargetsDir)
+		tufMappings, err := config.LoadTUFMappings(tufClient, opts.LocalTargetsDir)
 		if err != nil {
 			return nil, fmt.Errorf("failed to load tuf policy mappings by id: %w", err)
 		}
 		policy := tufMappings.Policies[opts.PolicyID]
 		if policy != nil {
-			return resolveTUFPolicy(opts, policy, "", "")
+			return resolveTUFPolicy(opts, tufClient, policy, "", "")
 		}
 		return nil, fmt.Errorf("policy with id %s not found", opts.PolicyID)
 	}
 	return nil, nil
 }
 
-func ResolvePolicy(ctx context.Context, detailsResolver oci.ImageDetailsResolver, opts *Options) (*Policy, error) {
+func ResolvePolicy(ctx context.Context, tufClient tuf.Downloader, detailsResolver oci.ImageDetailsResolver, opts *Options) (*Policy, error) {
-	p, err := resolvePolicyByID(opts)
+	p, err := resolvePolicyByID(opts, tufClient)
 	if err != nil {
 		return nil, fmt.Errorf("failed to resolve policy by id: %w", err)
 	}
@@ -175,7 +210,7 @@ func ResolvePolicy(ctx context.Context, detailsResolver oci.ImageDetailsResolver
 		return resolveLocalPolicy(opts, match.policy, imageName, match.matchedName)
 	}
 	// must check tuf
-	tufMappings, err := config.LoadTUFMappings(opts.TUFClient, opts.LocalTargetsDir)
+	tufMappings, err := config.LoadTUFMappings(tufClient, opts.LocalTargetsDir)
 	if err != nil {
 		return nil, fmt.Errorf("failed to load tuf policy mappings as fallback: %w", err)
 	}
@@ -184,7 +219,7 @@ func ResolvePolicy(ctx context.Context, detailsResolver oci.ImageDetailsResolver
 	if match.matchType == matchTypeMatchNoPolicy {
 		for _, mapping := range tufMappings.Policies {
 			if mapping.ID == match.rule.PolicyID {
-				return resolveTUFPolicy(opts, mapping, imageName, match.matchedName)
+				return resolveTUFPolicy(opts, tufClient, mapping, imageName, match.matchedName)
 			}
 		}
 	}
@@ -195,7 +230,7 @@ func ResolvePolicy(ctx context.Context, detailsResolver oci.ImageDetailsResolver
 		return nil, err
 	}
 	if match.matchType == matchTypePolicy {
-		return resolveTUFPolicy(opts, match.policy, imageName, match.matchedName)
+		return resolveTUFPolicy(opts, tufClient, match.policy, imageName, match.matchedName)
 	}
 	return nil, nil
 }
@@ -211,28 +246,28 @@ 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) {
+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 oci.NewRegistryAttestationResolver(resolver)
+				return attestation.NewRegistryResolver(resolver)
-			case *oci.LayoutResolver:
+			case *attestation.LayoutResolver:
 				return resolver, nil
 			default:
 				return nil, fmt.Errorf("unsupported image details resolver type: %T", resolver)
 			}
 		}
 		if mapping.Attestations.Repo != "" {
-			return oci.NewReferrersAttestationResolver(resolver, oci.WithReferrersRepo(mapping.Attestations.Repo))
+			return attestation.NewReferrersResolver(resolver, attestation.WithReferrersRepo(mapping.Attestations.Repo))
 		}
 	}
-	return oci.NewReferrersAttestationResolver(resolver)
+	return attestation.NewReferrersResolver(resolver)
 }

pkg/policy/policy_test.go

@@ -32,47 +32,49 @@ 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 := oci.MockResolver{
+	defaultResolver := attestation.MockResolver{
 		Envs: []*attestation.Envelope{loadAttestation(t, ExampleAttestation)},
 	}
 
 	testCases := []struct {
-		repo          string
+		repo            string
-		expectSuccess bool
+		expectSuccess   bool
-		isCanonical   bool
+		isCanonical     bool
-		resolver      oci.AttestationResolver
+		resolver        attestation.Resolver
-		policy        *policy.Options
+		policy          *policy.Options
-		policyID      string
+		policyID        string
-		errorStr      string
+		resolveErrorStr string
 	}{
-		{repo: "testdata/mock-tuf-allow", expectSuccess: true, isCanonical: false, resolver: defaultResolver},
+		{repo: "testdata/mock-tuf-allow", expectSuccess: true, resolver: defaultResolver},
-		{repo: "testdata/mock-tuf-allow", expectSuccess: true, isCanonical: false, resolver: defaultResolver, policyID: "docker-official-images"},
+		{repo: "testdata/mock-tuf-allow", expectSuccess: true, 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", resolver: defaultResolver, policyID: "non-existent-policy-id", resolveErrorStr: resolveErrorStr},
-		{repo: "testdata/mock-tuf-deny", expectSuccess: false, isCanonical: false, resolver: defaultResolver},
+		{repo: "testdata/mock-tuf-deny", resolver: defaultResolver},
-		{repo: "testdata/mock-tuf-verify-sig", expectSuccess: true, isCanonical: false, resolver: defaultResolver},
+		{repo: "testdata/mock-tuf-verify-sig", expectSuccess: true, resolver: defaultResolver},
-		{repo: "testdata/mock-tuf-wrong-key", expectSuccess: false, isCanonical: false, resolver: defaultResolver},
+		{repo: "testdata/mock-tuf-wrong-key", 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-allow-canonical", resolver: defaultResolver},
+		{repo: "testdata/mock-tuf-no-rego", resolver: defaultResolver, resolveErrorStr: "no policy file found in policy mapping"},
 	}
 
 	for _, tc := range testCases {
 		t.Run(tc.repo, func(t *testing.T) {
 			input := &policy.Input{
-				Digest:      "sha256:test-digest",
+				Digest: "sha256:test-digest",
-				PURL:        "test-purl",
+				PURL:   "test-purl",
-				IsCanonical: tc.isCanonical,
+			}
+			if !tc.isCanonical {
+				input.Tag = "test"
 			}
 
 			tufClient := tuf.NewMockTufClient(tc.repo, test.CreateTempDir(t, "", "tuf-dest"))
 			if tc.policy == nil {
 				tc.policy = &policy.Options{
-					TUFClient:       tufClient,
 					LocalTargetsDir: test.CreateTempDir(t, "", "tuf-targets"),
 					PolicyID:        tc.policyID,
 				}
@@ -85,10 +87,10 @@ func TestRegoEvaluator_Evaluate(t *testing.T) {
 			require.NoError(t, err)
 			resolver, err := policy.CreateImageDetailsResolver(src)
 			require.NoError(t, err)
-			policy, err := policy.ResolvePolicy(ctx, resolver, tc.policy)
+			policy, err := policy.ResolvePolicy(ctx, tufClient, 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")
@@ -117,10 +119,10 @@ func TestLoadingMappings(t *testing.T) {
 }
 
 func TestCreateAttestationResolver(t *testing.T) {
-	mockResolver := oci.MockResolver{
+	mockResolver := attestation.MockResolver{
 		Envs: []*attestation.Envelope{},
 	}
-	layoutResolver := &oci.LayoutResolver{}
+	layoutResolver := &attestation.LayoutResolver{}
 	registryResolver := &oci.RegistryImageDetailsResolver{}
 
 	nilRepoReferrers := &config.PolicyMapping{
@@ -166,11 +168,11 @@ func TestCreateAttestationResolver(t *testing.T) {
 				return
 			}
 			switch resolver.(type) {
-			case *oci.ReferrersResolver:
+			case *attestation.ReferrersResolver:
 				assert.Equal(t, tc.mapping.Attestations.Style, config.AttestationStyleReferrers)
-			case *oci.RegistryResolver:
+			case *attestation.RegistryResolver:
 				assert.Equal(t, tc.mapping.Attestations.Style, config.AttestationStyleAttached)
-			case *oci.LayoutResolver:
+			case *attestation.LayoutResolver:
 				assert.Equal(t, tc.mapping.Attestations.Style, config.AttestationStyleAttached)
 			}
 		})

pkg/policy/rego.go

@@ -7,8 +7,7 @@ import (
 	"os"
 	"path/filepath"
 
-	att "github.com/docker/attest/pkg/attestation"
+	"github.com/docker/attest/pkg/attestation"
-	"github.com/docker/attest/pkg/oci"
 	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)
+	env := new(attestation.Envelope)
-	opts := new(att.VerifyOptions)
+	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
 	}

pkg/policy/testdata/mock-tuf-allow-canonical/doi/policy.rego

@@ -2,6 +2,10 @@ package attest
 
 import rego.v1
 
-result := {
+default canonical = false
-  "success": input.isCanonical,
+
+canonical if {
+  not input.tag
 }
+
+result := {"success": canonical}

pkg/policy/testdata/mock-tuf-no-rego/doi/policy.yaml

@@ -0,0 +1 @@
+policy: "this is not rego"

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

pkg/policy/types.go

@@ -27,7 +27,7 @@ type Result struct {
 }
 
 type Options struct {
-	TUFClient        tuf.Downloader
+	TUFClientOptions *tuf.ClientOptions
 	LocalTargetsDir  string
 	LocalPolicyDir   string
 	PolicyID         string
@@ -40,12 +40,18 @@ type Policy struct {
 	Query        string
 	Mapping      *config.PolicyMapping
 	ResolvedName string
+	URI          string
+	Digest       map[string]string
 }
 
 type Input struct {
-	Digest      string `json:"digest"`
+	Digest         string `json:"digest"`
-	PURL        string `json:"purl"`
+	PURL           string `json:"purl"`
-	IsCanonical bool   `json:"isCanonical"`
+	Tag            string `json:"tag,omitempty"`
+	Domain         string `json:"domain"`
+	NormalizedName string `json:"normalized_name"`
+	FamiliarName   string `json:"familiar_name"`
+	Platform       string `json:"platform"`
 }
 
 type File struct {

pkg/signerverifier/README.md

@@ -0,0 +1,2 @@
+## signerverifier
+This package implements methods to sign and verify attestation envelopes.

pkg/tlog/README.md

@@ -0,0 +1,2 @@
+## tlog
+This package implements transparency logging.

pkg/tuf/README.md

@@ -0,0 +1,2 @@
+## tuf
+This package implements TUF clients for http and oci data sources.

pkg/tuf/example_registry_test.go

@@ -4,7 +4,6 @@ import (
 	"os"
 	"path/filepath"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/pkg/tuf"
 	"github.com/theupdateframework/go-tuf/v2/metadata"
 )
@@ -21,23 +20,20 @@ func ExampleNewClient_registry() {
 	metadataURI := "registry-1.docker.io/docker/tuf-metadata:latest"
 	targetsURI := "registry-1.docker.io/docker/tuf-targets"
 
-	registryClient, err := tuf.NewClient(embed.RootStaging.Data, tufOutputPath, metadataURI, targetsURI, tuf.NewMockVersionChecker())
+	registryClient, err := tuf.NewClient(&tuf.ClientOptions{tuf.DockerTUFRootStaging.Data, tufOutputPath, metadataURI, targetsURI, tuf.NewMockVersionChecker()})
 	if err != nil {
 		panic(err)
 	}
 
 	// 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)
 		}

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) {
+func (dc *MockTufClient) DownloadTarget(target string, filePath string) (file *TargetFile, err error) {
-	src, err := os.Open(filepath.Join(dc.srcPath, target))
+	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 {

pkg/tuf/registry_test.go

@@ -9,7 +9,6 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/docker/attest/internal/util"
 	"github.com/docker/attest/pkg/oci"
 	"github.com/google/go-containerregistry/pkg/crane"
@@ -32,6 +31,9 @@ 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) {
@@ -44,16 +46,16 @@ 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")
 	delegatedDir := CreateTempDir(t, dir, delegatedRole)
 	delegatedTargetFile := fmt.Sprintf("%s/%s", delegatedRole, targetFile)
 
-	cfg, err := config.New(metadataRepo, embed.RootDev.Data)
+	cfg, err := config.New(metadataRepo, DockerTUFRootDev.Data)
 	assert.NoError(t, err)
 
 	cfg.Fetcher = NewRegistryFetcher(metadataRepo, metadataImgTag, targetsRepo)
@@ -122,7 +124,7 @@ 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 +152,6 @@ 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 +184,8 @@ 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

pkg/tuf/tuf.go

@@ -1,6 +1,7 @@
 package tuf
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"io/fs"
@@ -20,6 +21,24 @@ import (
 	"github.com/theupdateframework/go-tuf/v2/metadata/updater"
 )
 
+type tufCtxKeyType struct{}
+
+var DownloaderCtxKey tufCtxKeyType
+
+// WithDownloader sets Downloader in context.
+func WithDownloader(ctx context.Context, downloader Downloader) context.Context {
+	return context.WithValue(ctx, DownloaderCtxKey, downloader)
+}
+
+// GetDownloader returns the Downloader from context and `true` if it exists, otherwise `nil` and `false`.
+func GetDownloader(ctx context.Context) (Downloader, bool) {
+	t, ok := ctx.Value(DownloaderCtxKey).(Downloader)
+	if !ok {
+		return nil, false
+	}
+	return t, true
+}
+
 type Source string
 
 const (
@@ -35,8 +54,13 @@ var (
 	DockerTUFRootDefault = embed.RootDefault
 )
 
+const (
+	defaultMetadataSource = "docker/tuf-metadata:latest"
+	defaultTargetsSource  = "docker/tuf-targets"
+)
+
 type Downloader interface {
-	DownloadTarget(target, filePath string) (actualFilePath string, data []byte, err error)
+	DownloadTarget(target, filePath string) (file *TargetFile, err error)
 }
 
 type Client struct {
@@ -44,19 +68,44 @@ type Client struct {
 	cfg     *config.UpdaterConfig
 }
 
+type TargetFile struct {
+	ActualFilePath string
+	TargetURI      string
+	Digest         string
+	Data           []byte
+}
+
+type ClientOptions struct {
+	InitialRoot    []byte
+	Path           string
+	MetadataSource string
+	TargetsSource  string
+	VersionChecker VersionChecker
+}
+
+func NewDockerDefaultClientOptions(tufPath string) *ClientOptions {
+	return &ClientOptions{
+		InitialRoot:    DockerTUFRootDefault.Data,
+		Path:           tufPath,
+		MetadataSource: defaultMetadataSource,
+		TargetsSource:  defaultTargetsSource,
+		VersionChecker: NewDefaultVersionChecker(),
+	}
+}
+
 // NewClient creates a new TUF client.
-func NewClient(initialRoot []byte, tufPath, metadataSource, targetsSource string, versionChecker VersionChecker) (*Client, error) {
+func NewClient(opts *ClientOptions) (*Client, error) {
 	var tufSource Source
-	if strings.HasPrefix(metadataSource, "https://") || strings.HasPrefix(metadataSource, "http://") {
+	if strings.HasPrefix(opts.MetadataSource, "https://") || strings.HasPrefix(opts.MetadataSource, "http://") {
 		tufSource = HTTPSource
 	} else {
 		tufSource = OCISource
 	}
 
-	tufRootDigest := util.SHA256Hex(initialRoot)
+	tufRootDigest := util.SHA256Hex(opts.InitialRoot)
 
 	// create a directory for each initial root.json
-	metadataPath := filepath.Join(tufPath, tufRootDigest)
+	metadataPath := filepath.Join(opts.Path, tufRootDigest)
 	err := os.MkdirAll(metadataPath, os.ModePerm)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create directory '%s': %w", metadataPath, err)
@@ -69,29 +118,29 @@ func NewClient(initialRoot []byte, tufPath, metadataSource, targetsSource string
 			return nil, fmt.Errorf("failed to read root.json: %w", err)
 		}
 		// write the root.json file to the metadata directory
-		err = os.WriteFile(rootFile, initialRoot, 0o666) // #nosec G306
+		err = os.WriteFile(rootFile, opts.InitialRoot, 0o666) // #nosec G306
 		if err != nil {
 			return nil, fmt.Errorf("Failed to write root.json %w", err)
 		}
-		rootBytes = initialRoot
+		rootBytes = opts.InitialRoot
 	}
 
 	// create updater configuration
-	cfg, err := config.New(metadataSource, rootBytes) // default config
+	cfg, err := config.New(opts.MetadataSource, rootBytes) // default config
 	if err != nil {
 		return nil, fmt.Errorf("failed to create TUF updater configuration: %w", err)
 	}
 	cfg.LocalMetadataDir = metadataPath
 	cfg.LocalTargetsDir = filepath.Join(metadataPath, "download")
-	cfg.RemoteTargetsURL = targetsSource
+	cfg.RemoteTargetsURL = opts.TargetsSource
 
 	if tufSource == OCISource {
-		metadataRepo, metadataTag, found := strings.Cut(metadataSource, ":")
+		metadataRepo, metadataTag, found := strings.Cut(opts.MetadataSource, ":")
 		if !found {
 			fmt.Printf("metadata tag not found in URL, using latest\n")
 			metadataTag = LatestTag
 		}
-		cfg.Fetcher = NewRegistryFetcher(metadataRepo, metadataTag, targetsSource)
+		cfg.Fetcher = NewRegistryFetcher(metadataRepo, metadataTag, opts.TargetsSource)
 	}
 
 	// create a new Updater instance
@@ -111,7 +160,7 @@ func NewClient(initialRoot []byte, tufPath, metadataSource, targetsSource string
 		cfg:     cfg,
 	}
 
-	err = versionChecker.CheckVersion(client)
+	err = opts.VersionChecker.CheckVersion(client)
 	if err != nil {
 		return nil, err
 	}
@@ -119,40 +168,69 @@ 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)
 	}
-
+	digest := util.SHA256Hex(data)
-	return actualFilePath, data, err
+	uri, err := t.generateTargetURI(targetInfo, digest)
+	return &TargetFile{ActualFilePath: actualFilePath, TargetURI: uri, Data: data, Digest: digest}, err
 }
 
 func (t *Client) GetMetadata() trustedmetadata.TrustedMetadata {

pkg/tuf/tuf_test.go

@@ -9,8 +9,8 @@ import (
 	"path/filepath"
 	"testing"
 
-	"github.com/docker/attest/internal/embed"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"github.com/theupdateframework/go-tuf/v2/metadata"
 )
 
@@ -65,18 +65,18 @@ func TestRootInit(t *testing.T) {
 	}
 
 	for _, tc := range testCases {
-		_, err := NewClient(embed.RootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker)
+		_, err := NewClient(&ClientOptions{DockerTUFRootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker})
 		assert.NoErrorf(t, err, "Failed to create TUF client: %v", err)
 
 		// recreation should work with same root
-		_, err = NewClient(embed.RootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker)
+		_, err = NewClient(&ClientOptions{DockerTUFRootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker})
 		assert.NoErrorf(t, err, "Failed to recreate TUF client: %v", err)
 
-		_, err = NewClient([]byte("broken"), tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker)
+		_, err = NewClient(&ClientOptions{[]byte("broken"), tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker})
 		assert.Errorf(t, err, "Expected error recreating TUF client with broken root: %v", err)
 
-		_, err = NewClient(embed.RootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysBadVersionChecker)
+		_, err = NewClient(&ClientOptions{DockerTUFRootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysBadVersionChecker})
-		assert.Errorf(t, err, "Expected error creating TUF client with bad attest version: %v", err)
+		assert.Errorf(t, err, "Expected error recreating TUF client with bad version checker")
 	}
 }
 
@@ -108,11 +108,13 @@ func TestDownloadTarget(t *testing.T) {
 	}{
 		{"http", server.URL + "/metadata", server.URL + "/targets"},
 		{"oci", regAddr.Host + "/tuf-metadata:latest", regAddr.Host + "/tuf-targets"},
+		{"http, download before init", server.URL + "/metadata", server.URL + "/targets"},
 	}
 
 	for _, tc := range testCases {
-		tufClient, err := NewClient(embed.RootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker)
+		tufClient, err := NewClient(&ClientOptions{DockerTUFRootDev.Data, tufPath, tc.metadataSource, tc.targetsSource, alwaysGoodVersionChecker})
-		assert.NoErrorf(t, err, "Failed to create TUF client: %v", err)
+		require.NoErrorf(t, err, "Failed to create TUF client: %v", err)
+		require.NotNil(t, tufClient.updater, "Failed to create updater")
 
 		// get trusted tuf metadata
 		trustedMetadata := tufClient.updater.GetTrustedMetadataSet()
@@ -122,14 +124,14 @@ 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)
 	}
 }

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)
 	}

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/`

test/README.md

@@ -0,0 +1,2 @@
+## test
+This directory contains static `testdata` used to run go tests.

test/testdata/local-policy-inputs/doi/policy.rego

@@ -0,0 +1,43 @@
+package attest
+
+import rego.v1
+
+keys := [{
+	"id": "a0c296026645799b2a297913878e81b0aefff2a0c301e97232f717e14402f3e4",
+	"key": "-----BEGIN PUBLIC KEY-----\nMFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEgH23D1i2+ZIOtVjmfB7iFvX8AhVN\n9CPJ4ie9axw+WRHozGnRy99U2dRge3zueBBg2MweF0zrToXGig2v3YOrdw==\n-----END PUBLIC KEY-----",
+	"from": "2023-12-15T14:00:00Z",
+	"to": null,
+	"status": "active",
+	"signing-format": "dssev1",
+}]
+
+provs(pred) := p if {
+	res := attest.fetch(pred)
+	not res.error
+	p := res.value
+}
+
+atts := union({
+	provs("https://slsa.dev/provenance/v0.2"),
+	provs("https://spdx.dev/Document"),
+})
+
+success if {
+	input.domain == "docker.io"
+	input.familiar_name == "test-image"
+	input.normalized_name == "library/test-image"
+	input.platform == "linux/amd64"
+	input.tag == "test"
+}
+
+result := {
+	"success": success,
+	"violations": set(),
+	"attestations": set(),
+	"summary": {
+		"subjects": set(),
+		"slsa_level": "SLSA_BUILD_LEVEL_3",
+		"verifier": "docker-official-images",
+		"policy_uri": "https://docker.com/official/policy/v0.1",
+	},
+}

test/testdata/local-policy-inputs/mapping.yaml

@@ -0,0 +1,18 @@
+version: v1
+kind: policy-mapping
+policies:
+  - id: docker-official-images
+    description: Docker Official Images
+    files:
+      - path: doi/policy.rego
+rules:
+  - pattern: "^docker[.]io/library/(.*)$"
+    policy-id: docker-official-images
+  - pattern: "repo$"
+    policy-id: docker-official-images
+  - pattern: "test-image$"
+    policy-id: docker-official-images
+  - pattern: "image-signer-verifier-test$"
+    policy-id: docker-official-images
+  - pattern: "library/(.*)$"
+    rewrite: docker.io/library/$1

test/testdata/local-policy-mirror/policy.rego

@@ -38,7 +38,7 @@ subjects contains subject if {
 }
 
 success if {
-	print("input:",input)
+	# print("input:",input)
 	true
 }
 

test/testdata/local-policy-no-policies/mapping.yaml

@@ -0,0 +1,4 @@
+version: v1
+kind: policy-mapping
+policies:
+rules: