cli/pkg/cmd/attestation/verification/extensions.go
Meredith Lancaster 8336f797ad use sigstore-go certificate.Summary type for criteria
Signed-off-by: Meredith Lancaster <malancas@github.com>
2024-10-31 16:27:21 -06:00

65 lines
2.3 KiB
Go

package verification
import (
"errors"
"fmt"
"strings"
"github.com/sigstore/sigstore-go/pkg/fulcio/certificate"
)
var (
GitHubOIDCIssuer = "https://token.actions.githubusercontent.com"
GitHubTenantOIDCIssuer = "https://token.actions.%s.ghe.com"
)
func VerifyCertExtensions(results []*AttestationProcessingResult, ec EnforcementCriteria) error {
if len(results) == 0 {
return errors.New("no attestations proccessing results")
}
var atLeastOneVerified bool
for _, attestation := range results {
if err := verifyCertExtensions(*attestation.VerificationResult.Signature.Certificate, ec); err != nil {
return err
}
atLeastOneVerified = true
}
if atLeastOneVerified {
return nil
} else {
return ErrNoAttestationsVerified
}
}
func verifyCertExtensions(verifiedCert certificate.Summary, criteria EnforcementCriteria) error {
if criteria.Certificate.SourceRepositoryOwnerURI != "" {
sourceRepositoryOwnerURI := verifiedCert.Extensions.SourceRepositoryOwnerURI
if !strings.EqualFold(criteria.Certificate.SourceRepositoryOwnerURI, sourceRepositoryOwnerURI) {
return fmt.Errorf("expected SourceRepositoryOwnerURI to be %s, got %s", criteria.Certificate.SourceRepositoryOwnerURI, sourceRepositoryOwnerURI)
}
}
// if repo is set, check the SourceRepositoryURI field
if criteria.Certificate.SourceRepositoryURI != "" {
sourceRepositoryURI := verifiedCert.Extensions.SourceRepositoryURI
if !strings.EqualFold(criteria.Certificate.SourceRepositoryURI, sourceRepositoryURI) {
return fmt.Errorf("expected SourceRepositoryURI to be %s, got %s", criteria.Certificate.SourceRepositoryURI, sourceRepositoryURI)
}
}
// if issuer is anything other than the default, use the user-provided value;
// otherwise, select the appropriate default based on the tenant
if criteria.Certificate.Issuer != "" {
certIssuer := verifiedCert.Extensions.Issuer
if !strings.EqualFold(criteria.Certificate.Issuer, certIssuer) {
if strings.Index(certIssuer, criteria.Certificate.Issuer+"/") == 0 {
return fmt.Errorf("expected Issuer to be %s, got %s -- if you have a custom OIDC issuer policy for your enterprise, use the --cert-oidc-issuer flag with your expected issuer", criteria.Certificate.Issuer, certIssuer)
}
return fmt.Errorf("expected Issuer to be %s, got %s", criteria.Certificate.Issuer, certIssuer)
}
}
return nil
}