fix: canonicalize Ed25519 algorithm casing

Author: GsCommand

README.md

@@ -9,7 +9,7 @@ Canonical crypto and receipt verification primitives for CommandLayer CLAS.
 - `metadata.proof.canonicalization = "json.sorted_keys.v1"`
 - `metadata.proof.hash.alg = "SHA-256"`
 - `metadata.proof.hash.value = <lowercase hex digest>`
-- `metadata.proof.signature.alg = "ed25519"`
+- `metadata.proof.signature.alg = "Ed25519"`
 - `metadata.proof.signature.value = <base64 signature>`
 - `metadata.proof.signature.kid = <required key id>`
 

src/compat.ts

@@ -35,7 +35,7 @@ export interface CommandLayerReceipt {
 export interface CommandLayerProof {
   canonicalization: string;
   hash: { alg: "SHA-256"; value: string };
-  signature: { alg: typeof SIGNATURE_ALG; value: string; kid: string };
+  signature: { alg: typeof SIGNATURE_ALG | "ed25519"; value: string; kid: string };
 }
 
 export function buildCanonicalProof(receipt: CommandLayerReceipt): string {
@@ -121,7 +121,10 @@ export function verifyCommandLayerReceipt(
   if (proof.hash?.alg && proof.hash.alg !== "SHA-256") {
     errors.push("ERR_UNSUPPORTED_HASH_ALG");
   }
-  if (proof.signature?.alg && proof.signature.alg !== SIGNATURE_ALG) {
+  const signatureAlg = proof.signature?.alg === "ed25519"
+    ? SIGNATURE_ALG
+    : proof.signature?.alg;
+  if (signatureAlg && signatureAlg !== SIGNATURE_ALG) {
     errors.push("ERR_UNSUPPORTED_SIGNATURE_ALG");
   }
 

src/crypto.ts

@@ -17,7 +17,7 @@ import { sign, verify, generateKeyPairSync } from "node:crypto";
 
 export const PROTOCOL_VERSION = "1.1.0" as const;
 export const CANONICAL_METHOD = "json.sorted_keys.v1" as const;
-export const SIGNATURE_ALG = "ed25519" as const;
+export const SIGNATURE_ALG = "Ed25519" as const;
 
 /** The ENS text record key for the signer's public key. */
 export const ENS_KEY_PUB = "cl.sig.pub" as const;

src/receipt.ts

@@ -4,7 +4,7 @@
  * v1.1.0 signed layered receipt builder and verifier.
  *
  * Proof field names (canonical, matches clas schema):
- *   proof.alg        — signature algorithm ("ed25519")
+ *   proof.alg        — signature algorithm ("Ed25519")
  *   proof.kid        — key identifier (from ENS cl.sig.kid)
  *   proof.signer_id  — ENS name of signer (e.g. runtime.commandlayer.eth)
  *   proof.canonical  — canonicalization method ("json.sorted_keys.v1")
@@ -31,8 +31,8 @@ export interface ReceiptPayload {
 }
 
 export interface ReceiptProof {
-  /** Signature algorithm. Always "ed25519". */
-  alg: typeof SIGNATURE_ALG;
+  /** Signature algorithm. Canonical "Ed25519" (legacy lowercase accepted in verification). */
+  alg: typeof SIGNATURE_ALG | "ed25519";
   /** Key identifier from ENS cl.sig.kid */
   kid: string;
   /** ENS name of the signer */
@@ -177,7 +177,8 @@ export function verifyReceipt(
   checks.structureValid = true;
 
   // Algorithm check
-  if (proof.alg !== SIGNATURE_ALG) {
+  const normalizedAlg = proof.alg === "ed25519" ? SIGNATURE_ALG : proof.alg;
+  if (normalizedAlg !== SIGNATURE_ALG) {
     return {
       valid: false,
       checks,

test/compat.test.ts

@@ -23,7 +23,7 @@ describe("canonical CLAS proof envelope", () => {
     assert.equal(proof.canonicalization, "json.sorted_keys.v1");
     assert.equal(proof.hash.alg, "SHA-256");
     assert.ok(proof.hash.value);
-    assert.equal(proof.signature.alg, "ed25519");
+    assert.equal(proof.signature.alg, "Ed25519");
     assert.ok(proof.signature.value);
     assert.equal(proof.signature.kid, "testKid");
 
@@ -34,6 +34,38 @@ describe("canonical CLAS proof envelope", () => {
     assert.equal(isSignedCommandLayerReceipt(signed), true);
   });
 
+
+
+  test("verifies canonical Ed25519 algorithm without caller normalization", () => {
+    const signed = signCommandLayerReceipt(baseReceipt, { privateKeyPem: kp.privateKeyPem, kid: "testKid" });
+    const proof = signed.metadata!.proof!;
+
+    const canonical = verifyCommandLayerReceipt(
+      { ...signed, metadata: { ...signed.metadata!, proof: { ...proof, signature: { ...proof.signature, alg: "Ed25519" } } } },
+      { publicKeyPemOrDer: kp.publicKeyPem }
+    );
+    assert.equal(canonical.ok, true);
+
+    const legacy = verifyCommandLayerReceipt(
+      { ...signed, metadata: { ...signed.metadata!, proof: { ...proof, signature: { ...proof.signature, alg: "ed25519" } } } },
+      { publicKeyPemOrDer: kp.publicKeyPem }
+    );
+    assert.equal(legacy.ok, true);
+  });
+
+  test("fails on unsupported signature algorithms", () => {
+    const signed = signCommandLayerReceipt(baseReceipt, { privateKeyPem: kp.privateKeyPem, kid: "testKid" });
+    const proof = signed.metadata!.proof!;
+
+    const bad = verifyCommandLayerReceipt(
+      { ...signed, metadata: { ...signed.metadata!, proof: { ...proof, signature: { ...proof.signature, alg: "rsa" as never } } } },
+      { publicKeyPemOrDer: kp.publicKeyPem }
+    );
+
+    assert.equal(bad.status, "INVALID");
+    assert.ok(bad.errors.includes("ERR_UNSUPPORTED_SIGNATURE_ALG"));
+  });
+
   test("requires signature.kid to be a non-empty string", () => {
     const signed = signCommandLayerReceipt(baseReceipt, { privateKeyPem: kp.privateKeyPem, kid: "testKid" });
     const p = signed.metadata!.proof!;

test/receipt.test.ts

@@ -32,7 +32,7 @@ describe("signReceipt", () => {
 
     const proof = receipt.signature.proof;
     // Field names must match protocol spec
-    assert.strictEqual(proof.alg, "ed25519");          // not signature_alg
+    assert.strictEqual(proof.alg, "Ed25519");          // not signature_alg
     assert.strictEqual(proof.kid, "vC4WbcNoq2znSCiQ"); // not key_id
     assert.strictEqual(proof.signer_id, "runtime.commandlayer.eth"); // not signer
     assert.strictEqual(proof.canonical, "json.sorted_keys.v1");
@@ -163,6 +163,19 @@ describe("verifyReceipt — full round trip", () => {
     assert.strictEqual(result.checks.signatureValid, false);
   });
 
+
+
+  it("accepts legacy lowercase ed25519 for compatibility", () => {
+    const { privateKeyPem, rawPublicKey } = generateEd25519KeyPair();
+    const signed = signReceipt(makePayload(), {
+      privateKeyPem, kid: "kid1", signerEns: "test.eth",
+    });
+    (signed.signature.proof as Record<string, unknown>).alg = "ed25519";
+
+    const result = verifyReceipt(signed, { rawPublicKey });
+    assert.strictEqual(result.valid, true);
+  });
+
   it("rejects unknown algorithm", () => {
     const { privateKeyPem, rawPublicKey } = generateEd25519KeyPair();
     const signed = signReceipt(makePayload(), {
@@ -203,7 +216,7 @@ describe("isSignedLayeredReceipt", () => {
   it("returns false when signature is empty string", () => {
     const obj = {
       receipt: { verb: "test", version: "1.1.0", agent: "x", timestamp: "t" },
-      signature: { proof: { alg: "ed25519", signature: "", signer_id: "x", kid: "k", canonical: "json.sorted_keys.v1" } },
+      signature: { proof: { alg: "Ed25519", signature: "", signer_id: "x", kid: "k", canonical: "json.sorted_keys.v1" } },
     };
     assert.strictEqual(isSignedLayeredReceipt(obj), false);
   });