Merge pull request #1 from kyverno/GHSA-vfp6-jrw2-99g9-fix-in-cosign-…

…v1.13.1

feat: add GHSA-vfp6-jrw2-99g9 fixes in cosign v1.13.1

.github/workflows/kind-verify-attestation.yaml

@@ -36,7 +36,7 @@ jobs:
 
     env:
       KO_DOCKER_REPO: "registry.local:5000/policy-controller"
-      SCAFFOLDING_RELEASE_VERSION: "v0.4.8"
+      SCAFFOLDING_RELEASE_VERSION: "v0.6.8"
       GO111MODULE: on
       GOFLAGS: -ldflags=-s -ldflags=-w
       KOCACHE: ~/ko

Makefile

@@ -148,9 +148,9 @@ ko-sget:
 .PHONY: ko-local
 ko-local:
 	$(create_kocache_path)
-	LDFLAGS="$(LDFLAGS)" GIT_HASH=$(GIT_HASH) GIT_VERSION=$(GIT_VERSION) \
+	KO_DOCKER_REPO=ko.local LDFLAGS="$(LDFLAGS)" GIT_HASH=$(GIT_HASH) GIT_VERSION=$(GIT_VERSION) \
 	KOCACHE=$(KOCACHE_PATH) ko build --base-import-paths \
-		--tags $(GIT_VERSION) --tags $(GIT_HASH) --local \
+		--tags $(GIT_VERSION) --tags $(GIT_HASH) \
 		$(ARTIFACT_HUB_LABELS) \
 		github.com/sigstore/cosign/cmd/cosign
 

pkg/cosign/fetch.go

@@ -29,6 +29,8 @@ import (
 	"golang.org/x/sync/errgroup"
 )
 
+const maxAllowedSigsOrAtts = 100
+
 type SignedPayload struct {
 	Base64Signature string
 	Payload         []byte
@@ -78,6 +80,10 @@ func FetchSignaturesForReference(ctx context.Context, ref name.Reference, opts .
 		return nil, fmt.Errorf("no signatures associated with %s", ref)
 	}
 
+	if len(l) > maxAllowedSigsOrAtts {
+		return nil, fmt.Errorf("maximum number of signatures on an image is %d, found %d", maxAllowedSigsOrAtts, len(l))
+	}
+
 	signatures := make([]SignedPayload, len(l))
 	var g errgroup.Group
 	g.SetLimit(runtime.NumCPU())
@@ -130,6 +136,10 @@ func FetchAttestationsForReference(ctx context.Context, ref name.Reference, opts
 		return nil, fmt.Errorf("no attestations associated with %s", ref)
 	}
 
+	if len(l) > maxAllowedSigsOrAtts {
+		return nil, fmt.Errorf("maximum number of attestations on an image is %d, found %d", maxAllowedSigsOrAtts, len(l))
+	}
+
 	attestations := make([]AttestationPayload, len(l))
 	var g errgroup.Group
 	g.SetLimit(runtime.NumCPU())

test/e2e_test.go

@@ -361,6 +361,81 @@ func TestAttestationReplaceCreate(t *testing.T) {
 	}
 }
 
+func TestExcessiveAttestations(t *testing.T) {
+	repo, stop := reg(t)
+	defer stop()
+	td := t.TempDir()
+
+	imgName := path.Join(repo, "cosign-attest-download-e2e")
+
+	_, _, cleanup := mkimage(t, imgName)
+	defer cleanup()
+
+	_, privKeyPath, _ := keypair(t, td)
+	ko := options.KeyOpts{KeyRef: privKeyPath, PassFunc: passFunc}
+
+	ctx := context.Background()
+
+	slsaAttestation := `{ "buildType": "x", "builder": { "id": "2" }, "recipe": {} }`
+	slsaAttestationPath := filepath.Join(td, "attestation.slsa.json")
+	if err := os.WriteFile(slsaAttestationPath, []byte(slsaAttestation), 0600); err != nil {
+		t.Fatal(err)
+	}
+
+	vulnAttestation := `
+	{
+    "invocation": {
+      "parameters": null,
+      "uri": "invocation.example.com/cosign-testing",
+      "event_id": "",
+      "builder.id": ""
+    },
+    "scanner": {
+      "uri": "fakescanner.example.com/cosign-testing",
+      "version": "",
+      "db": {
+        "uri": "",
+        "version": ""
+      },
+      "result": null
+    },
+    "metadata": {
+      "scanStartedOn": "2022-04-12T00:00:00Z",
+      "scanFinishedOn": "2022-04-12T00:10:00Z"
+    }
+}
+`
+	ref, err := name.ParseReference(imgName)
+	if err != nil {
+		t.Fatal(err)
+	}
+	regOpts := options.RegistryOptions{}
+	ociremoteOpts, err := regOpts.ClientOpts(ctx)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for i := 0; i < 102; i++ {
+		vulnAttestationPath := filepath.Join(td, fmt.Sprintf("attestation-%d.vuln.json", i))
+		if err := os.WriteFile(vulnAttestationPath, []byte(vulnAttestation), 0600); err != nil {
+			t.Fatal(err)
+		}
+
+		// Attest again with replace=true, replacing the previous attestation
+		must(attest.AttestCmd(ctx, ko, options.RegistryOptions{}, imgName, "", "", false, vulnAttestationPath, false,
+			"vuln", false, 30*time.Second, false), t)
+	}
+
+	_, err = cosign.FetchAttestationsForReference(ctx, ref, ociremoteOpts...)
+	if err == nil {
+		t.Fatalf("Expected an error, but 'err' was 'nil'")
+	}
+	expectedError := "maximum number of attestations on an image is 100, found 102"
+	if err.Error() != expectedError {
+		t.Errorf("Exted the error to be: '%s' but it was '%s'", expectedError, err.Error())
+	}
+}
+
 func TestAttestationReplace(t *testing.T) {
 	repo, stop := reg(t)
 	defer stop()
@@ -505,6 +580,35 @@ func TestDuplicateSign(t *testing.T) {
 	}
 }
 
+func TestExcessiveSignatures(t *testing.T) {
+	repo, stop := reg(t)
+	defer stop()
+	td := t.TempDir()
+
+	imgName := path.Join(repo, "cosign-e2e")
+
+	_, _, cleanup := mkimage(t, imgName)
+	defer cleanup()
+
+	ctx := context.Background()
+
+	for i := 0; i < 102; i++ {
+		_, privKeyPath, _ := keypair(t, td)
+
+		// Sign the image
+		ko := options.KeyOpts{KeyRef: privKeyPath, PassFunc: passFunc}
+		must(sign.SignCmd(ro, ko, options.RegistryOptions{}, nil, []string{imgName}, "", "", true, "", "", "", false, false, "", false), t)
+	}
+	err := download.SignatureCmd(ctx, options.RegistryOptions{}, imgName)
+	if err == nil {
+		t.Fatal("Expected an error, but 'err' was 'nil'")
+	}
+	expectedErr := "maximum number of signatures on an image is 100, found 102"
+	if err.Error() != expectedErr {
+		t.Fatalf("Expected the error '%s', but got the error '%s'", expectedErr, err.Error())
+	}
+}
+
 func TestKeyURLVerify(t *testing.T) {
 	// TODO: re-enable once distroless images are being signed by the new client
 	t.Skip()