refactor(reef): use Noble byte utilities

extensions/reef/protocol/audit.ts

@@ -1,7 +1,7 @@
 import { gcm } from "@noble/ciphers/aes.js";
 import { ed25519 } from "@noble/curves/ed25519.js";
 import { sha256 } from "@noble/hashes/sha2.js";
-import { randomBytes } from "@noble/hashes/utils.js";
+import { concatBytes, randomBytes } from "@noble/hashes/utils.js";
 import { canonicalBytes, canonicalJson } from "./canonical.js";
 import { base64, base64url, decodeUtf8, fromBase64, fromBase64url, hex, utf8 } from "./encoding.js";
 
@@ -187,10 +187,7 @@ function encryptSensitive(
           throw new Error("invalid audit nonce");
         }
         const ciphertext = gcm(key, nonce).encrypt(utf8(child));
-        const combined = new Uint8Array(nonce.length + ciphertext.length);
-        combined.set(nonce);
-        combined.set(ciphertext, nonce.length);
-        output[field] = { enc: base64(combined) };
+        output[field] = { enc: base64(concatBytes(nonce, ciphertext)) };
       } else {
         output[field] = encryptSensitive(child, key, rng);
       }
@@ -230,10 +227,7 @@ function decryptSensitive(value: unknown, key: Uint8Array, field?: string): unkn
 function hashEntry(previous: string, event: AuditEvent): string {
   const previousBytes = previous === "" ? new Uint8Array() : fromHex(previous);
   const eventBytes = canonicalBytes(event);
-  const combined = new Uint8Array(previousBytes.length + eventBytes.length);
-  combined.set(previousBytes);
-  combined.set(eventBytes, previousBytes.length);
-  return hex(sha256(combined));
+  return hex(sha256(concatBytes(previousBytes, eventBytes)));
 }
 
 function validateAuditKey(key: Uint8Array): Uint8Array {

extensions/reef/protocol/encoding.ts

@@ -1,13 +1,10 @@
-const encoder = new TextEncoder();
+export { bytesToHex as hex, equalBytes, utf8ToBytes as utf8 } from "@noble/ciphers/utils.js";
+
 const decoder = new TextDecoder("utf-8", { fatal: true });
 
 const alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
 const base64Alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 
-export function utf8(value: string): Uint8Array {
-  return encoder.encode(value);
-}
-
 export function decodeUtf8(value: Uint8Array): string {
   return decoder.decode(value);
 }
@@ -99,18 +96,3 @@ export function fromBase64(value: string): Uint8Array {
   }
   return output;
 }
-
-export function hex(value: Uint8Array): string {
-  return Array.from(value, (byte) => byte.toString(16).padStart(2, "0")).join("");
-}
-
-export function equalBytes(a: Uint8Array, b: Uint8Array): boolean {
-  if (a.length !== b.length) {
-    return false;
-  }
-  let difference = 0;
-  for (let index = 0; index < a.length; index++) {
-    difference |= a[index]! ^ b[index]!;
-  }
-  return difference === 0;
-}

extensions/reef/protocol/node.ts

@@ -1,7 +1,7 @@
 import { mkdir, open as openFile, readFile } from "node:fs/promises";
 import { dirname } from "node:path";
 import { gcm } from "@noble/ciphers/aes.js";
-import { randomBytes } from "@noble/hashes/utils.js";
+import { concatBytes, randomBytes } from "@noble/hashes/utils.js";
 import { createAuditEntry, verifyChain, type AuditEntry, type AuditStore } from "./audit.js";
 import { canonicalBytes } from "./canonical.js";
 import { base64, decodeUtf8, fromBase64 } from "./encoding.js";
@@ -293,10 +293,7 @@ function encryptReplayBody(
     throw new Error("replay body rng returned invalid nonce");
   }
   const ciphertext = gcm(key, nonce).encrypt(canonicalBytes(body));
-  const packed = new Uint8Array(nonce.length + ciphertext.length);
-  packed.set(nonce);
-  packed.set(ciphertext, nonce.length);
-  return { enc: base64(packed) };
+  return { enc: base64(concatBytes(nonce, ciphertext)) };
 }
 
 function decryptReplayBody(body: EncryptedReplayBody, key: Uint8Array): MessageBody {