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//go:build debian_no_fulcio
// +build debian_no_fulcio
package signature
import (
"context"
"os"
"path"
"testing"
"github.com/containers/image/v5/directory"
"github.com/containers/image/v5/docker/reference"
"github.com/containers/image/v5/internal/image"
"github.com/containers/image/v5/internal/imagesource"
"github.com/containers/image/v5/internal/private"
"github.com/containers/image/v5/types"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
// dirImageMock returns a private.UnparsedImage for a directory, claiming a specified dockerReference.
func dirImageMock(t *testing.T, dir, dockerReference string) private.UnparsedImage {
ref, err := reference.ParseNormalizedNamed(dockerReference)
require.NoError(t, err)
return dirImageMockWithRef(t, dir, refImageReferenceMock{ref: ref})
}
// dirImageMockWithRef returns a private.UnparsedImage for a directory, claiming a specified ref.
func dirImageMockWithRef(t *testing.T, dir string, ref types.ImageReference) private.UnparsedImage {
srcRef, err := directory.NewReference(dir)
require.NoError(t, err)
src, err := srcRef.NewImageSource(context.Background(), nil)
require.NoError(t, err)
t.Cleanup(func() {
err := src.Close()
require.NoError(t, err)
})
return image.UnparsedInstance(&dirImageSourceMock{
ImageSource: imagesource.FromPublic(src),
ref: ref,
}, nil)
}
// dirImageSourceMock inherits dirImageSource, but overrides its Reference method.
type dirImageSourceMock struct {
private.ImageSource
ref types.ImageReference
}
func (d *dirImageSourceMock) Reference() types.ImageReference {
return d.ref
}
func TestPRSignedByIsSignatureAuthorAccepted(t *testing.T) {
ktGPG := SBKeyTypeGPGKeys
prm := NewPRMMatchExact()
testImage := dirImageMock(t, "fixtures/dir-img-valid", "testing/manifest:latest")
testImageSig, err := os.ReadFile("fixtures/dir-img-valid/signature-1")
require.NoError(t, err)
keyData, err := os.ReadFile("fixtures/public-key.gpg")
require.NoError(t, err)
// Successful validation, with KeyPath, KeyPaths and KeyData.
for _, fn := range []func() (PolicyRequirement, error){
func() (PolicyRequirement, error) {
return NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
},
// Test the files in both orders, to make sure the correct public keys accepted in either position.
func() (PolicyRequirement, error) {
return NewPRSignedByKeyPaths(ktGPG, []string{"fixtures/public-key-1.gpg", "fixtures/public-key-1.gpg"}, prm)
},
func() (PolicyRequirement, error) {
return NewPRSignedByKeyPaths(ktGPG, []string{"fixtures/public-key-2.gpg", "fixtures/public-key-1.gpg"}, prm)
},
func() (PolicyRequirement, error) {
return NewPRSignedByKeyData(ktGPG, keyData, prm)
},
} {
pr, err := fn()
require.NoError(t, err)
sar, parsedSig, err := pr.isSignatureAuthorAccepted(context.Background(), testImage, testImageSig)
assertSARAccepted(t, sar, parsedSig, err, Signature{
DockerManifestDigest: TestImageManifestDigest,
DockerReference: "testing/manifest:latest",
})
}
// Unimplemented and invalid KeyType values
for _, keyType := range []sbKeyType{SBKeyTypeSignedByGPGKeys,
SBKeyTypeX509Certificates,
SBKeyTypeSignedByX509CAs,
sbKeyType("This is invalid"),
} {
// Do not use NewPRSignedByKeyData, because it would reject invalid values.
pr := &prSignedBy{
KeyType: keyType,
KeyData: keyData,
SignedIdentity: prm,
}
// Pass nil pointers to, kind of, test that the return value does not depend on the parameters.
sar, parsedSig, err := pr.isSignatureAuthorAccepted(context.Background(), nil, nil)
assertSARRejected(t, sar, parsedSig, err)
}
// Invalid KeyPath/KeyPaths/KeyData combinations.
for _, fn := range []func() (PolicyRequirement, error){
// Two or more of KeyPath, KeyPaths and KeyData set. Do not use NewPRSignedBy*, because it would reject this.
func() (PolicyRequirement, error) {
return &prSignedBy{KeyType: ktGPG, KeyPath: "fixtures/public-key.gpg", KeyPaths: []string{"fixtures/public-key-1.gpg", "fixtures/public-key-2.gpg"}, KeyData: keyData, SignedIdentity: prm}, nil
},
func() (PolicyRequirement, error) {
return &prSignedBy{KeyType: ktGPG, KeyPath: "fixtures/public-key.gpg", KeyPaths: []string{"fixtures/public-key-1.gpg", "fixtures/public-key-2.gpg"}, SignedIdentity: prm}, nil
},
func() (PolicyRequirement, error) {
return &prSignedBy{KeyType: ktGPG, KeyPath: "fixtures/public-key.gpg", KeyData: keyData, SignedIdentity: prm}, nil
},
func() (PolicyRequirement, error) {
return &prSignedBy{KeyType: ktGPG, KeyPaths: []string{"fixtures/public-key-1.gpg", "fixtures/public-key-2.gpg"}, KeyData: keyData, SignedIdentity: prm}, nil
},
// None of KeyPath, KeyPaths and KeyData set. Do not use NewPRSignedBy*, because it would reject this.
func() (PolicyRequirement, error) {
return &prSignedBy{KeyType: ktGPG, SignedIdentity: prm}, nil
},
func() (PolicyRequirement, error) { // Invalid KeyPath
return NewPRSignedByKeyPath(ktGPG, "/this/does/not/exist", prm)
},
func() (PolicyRequirement, error) { // Invalid KeyPaths
return NewPRSignedByKeyPaths(ktGPG, []string{"/this/does/not/exist"}, prm)
},
func() (PolicyRequirement, error) { // One of the KeyPaths is invalid
return NewPRSignedByKeyPaths(ktGPG, []string{"fixtures/public-key.gpg", "/this/does/not/exist"}, prm)
},
} {
pr, err := fn()
require.NoError(t, err)
// Pass nil pointers to, kind of, test that the return value does not depend on the parameters.
sar, parsedSig, err := pr.isSignatureAuthorAccepted(context.Background(), nil, nil)
assertSARRejected(t, sar, parsedSig, err)
}
// Errors initializing the temporary GPG directory and mechanism are not obviously easy to reach.
// KeyData has no public keys.
pr, err := NewPRSignedByKeyData(ktGPG, []byte{}, prm)
require.NoError(t, err)
// Pass nil pointers to, kind of, test that the return value does not depend on the parameters.
sar, parsedSig, err := pr.isSignatureAuthorAccepted(context.Background(), nil, nil)
assertSARRejectedPolicyRequirement(t, sar, parsedSig, err)
// A signature which does not GPG verify
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
// Pass a nil pointer to, kind of, test that the return value does not depend on the image parameter.
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), nil, []byte("invalid signature"))
assertSARRejected(t, sar, parsedSig, err)
// A valid signature using an unknown key.
// (This is (currently?) rejected through the "mech.Verify fails" path, not the "!identityFound" path,
// because we use a temporary directory and only import the trusted keys.)
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
sig, err := os.ReadFile("fixtures/unknown-key.signature")
require.NoError(t, err)
// Pass a nil pointer to, kind of, test that the return value does not depend on the image parameter..
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), nil, sig)
assertSARRejected(t, sar, parsedSig, err)
// A valid signature of an invalid JSON.
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
sig, err = os.ReadFile("fixtures/invalid-blob.signature")
require.NoError(t, err)
// Pass a nil pointer to, kind of, test that the return value does not depend on the image parameter..
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), nil, sig)
assertSARRejected(t, sar, parsedSig, err)
assert.IsType(t, InvalidSignatureError{}, err)
// A valid signature with a rejected identity.
nonmatchingPRM, err := NewPRMExactReference("this/doesnt:match")
require.NoError(t, err)
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", nonmatchingPRM)
require.NoError(t, err)
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), testImage, testImageSig)
assertSARRejectedPolicyRequirement(t, sar, parsedSig, err)
// Error reading image manifest
image := dirImageMock(t, "fixtures/dir-img-no-manifest", "testing/manifest:latest")
sig, err = os.ReadFile("fixtures/dir-img-no-manifest/signature-1")
require.NoError(t, err)
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), image, sig)
assertSARRejected(t, sar, parsedSig, err)
// Error computing manifest digest
image = dirImageMock(t, "fixtures/dir-img-manifest-digest-error", "testing/manifest:latest")
sig, err = os.ReadFile("fixtures/dir-img-manifest-digest-error/signature-1")
require.NoError(t, err)
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), image, sig)
assertSARRejected(t, sar, parsedSig, err)
// A valid signature with a non-matching manifest
image = dirImageMock(t, "fixtures/dir-img-modified-manifest", "testing/manifest:latest")
sig, err = os.ReadFile("fixtures/dir-img-modified-manifest/signature-1")
require.NoError(t, err)
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
sar, parsedSig, err = pr.isSignatureAuthorAccepted(context.Background(), image, sig)
assertSARRejectedPolicyRequirement(t, sar, parsedSig, err)
}
// createInvalidSigDir creates a directory suitable for dirImageMock, in which image.Signatures()
// fails.
func createInvalidSigDir(t *testing.T) string {
dir := t.TempDir()
err := os.WriteFile(path.Join(dir, "manifest.json"), []byte("{}"), 0644)
require.NoError(t, err)
// Creating a 000-permissions file would work for unprivileged accounts, but root (in particular,
// in the Docker container we use for testing) would still have access. So, create a symlink
// pointing to itself, to cause an ELOOP. (Note that a symlink pointing to a nonexistent file would be treated
// just like a nonexistent signature file, and not an error.)
err = os.Symlink("signature-1", path.Join(dir, "signature-1"))
require.NoError(t, err)
return dir
}
func TestPRSignedByIsRunningImageAllowed(t *testing.T) {
ktGPG := SBKeyTypeGPGKeys
prm := NewPRMMatchExact()
// A simple success case: single valid signature.
image := dirImageMock(t, "fixtures/dir-img-valid", "testing/manifest:latest")
pr, err := NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err := pr.isRunningImageAllowed(context.Background(), image)
assertRunningAllowed(t, allowed, err)
// Error reading signatures
invalidSigDir := createInvalidSigDir(t)
image = dirImageMock(t, invalidSigDir, "testing/manifest:latest")
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err = pr.isRunningImageAllowed(context.Background(), image)
assertRunningRejected(t, allowed, err)
// No signatures
image = dirImageMock(t, "fixtures/dir-img-unsigned", "testing/manifest:latest")
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err = pr.isRunningImageAllowed(context.Background(), image)
assertRunningRejectedPolicyRequirement(t, allowed, err)
// 1 invalid signature: use dir-img-valid, but a non-matching Docker reference
image = dirImageMock(t, "fixtures/dir-img-valid", "testing/manifest:notlatest")
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err = pr.isRunningImageAllowed(context.Background(), image)
assertRunningRejectedPolicyRequirement(t, allowed, err)
// 2 valid signatures
image = dirImageMock(t, "fixtures/dir-img-valid-2", "testing/manifest:latest")
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err = pr.isRunningImageAllowed(context.Background(), image)
assertRunningAllowed(t, allowed, err)
// One invalid, one valid signature (in this order)
image = dirImageMock(t, "fixtures/dir-img-mixed", "testing/manifest:latest")
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err = pr.isRunningImageAllowed(context.Background(), image)
assertRunningAllowed(t, allowed, err)
// 2 invalid signatures: use dir-img-valid-2, but a non-matching Docker reference
image = dirImageMock(t, "fixtures/dir-img-valid-2", "testing/manifest:notlatest")
pr, err = NewPRSignedByKeyPath(ktGPG, "fixtures/public-key.gpg", prm)
require.NoError(t, err)
allowed, err = pr.isRunningImageAllowed(context.Background(), image)
assertRunningRejectedPolicyRequirement(t, allowed, err)
}
|
