Files
attest/policy/match.go
James Carnegie 8982778507 refactor! remove pkg directory (#145)
* refactor!: remove pkg directory

* chore: include breaking changes in draft
2024-09-02 16:17:50 +01:00

66 lines
1.9 KiB
Go

package policy
import (
"fmt"
"github.com/docker/attest/config"
)
type matchType string
const (
matchTypePolicy matchType = "policy"
matchTypeMatchNoPolicy matchType = "match_no_policy"
matchTypeNoMatch matchType = "no_match"
)
type policyMatch struct {
matchType matchType
policy *config.PolicyMapping
rule *config.PolicyRule
matchedName string
}
func findPolicyMatch(imageName string, mappings *config.PolicyMappings) (*policyMatch, error) {
if mappings == nil {
return &policyMatch{matchType: matchTypeNoMatch, matchedName: imageName}, nil
}
return findPolicyMatchImpl(imageName, mappings, make(map[*config.PolicyRule]bool))
}
func findPolicyMatchImpl(imageName string, mappings *config.PolicyMappings, matched map[*config.PolicyRule]bool) (*policyMatch, error) {
for _, rule := range mappings.Rules {
if rule.Pattern.MatchString(imageName) {
switch {
case rule.PolicyID == "" && rule.Replacement == "":
return nil, fmt.Errorf("rule %s has neither policy-id nor rewrite", rule.Pattern)
case rule.PolicyID != "" && rule.Replacement != "":
return nil, fmt.Errorf("rule %s has both policy-id and rewrite", rule.Pattern)
case rule.PolicyID != "":
policy := mappings.Policies[rule.PolicyID]
if policy != nil {
return &policyMatch{
matchType: matchTypePolicy,
policy: policy,
rule: rule,
matchedName: imageName,
}, nil
}
return &policyMatch{
matchType: matchTypeMatchNoPolicy,
rule: rule,
matchedName: imageName,
}, nil
case rule.Replacement != "":
if matched[rule] {
return nil, fmt.Errorf("rewrite loop detected")
}
matched[rule] = true
imageName = rule.Pattern.ReplaceAllString(imageName, rule.Replacement)
return findPolicyMatchImpl(imageName, mappings, matched)
}
}
}
return &policyMatch{matchType: matchTypeNoMatch, matchedName: imageName}, nil
}