Merge pull request #6341 from BitGo/BTC-2226.refactor-extractAddressBufferFromPayGoAttestationProof

feat(utxo-core): extractMsgBufferFromPayGoAttestationProof refactor

Author: davidkaplanbitgo

modules/utxo-core/src/paygo/index.ts

@@ -1,2 +1,2 @@
-export * from './ExtractAddressPayGoAttestation';
+export * from './parsePayGoAttestation';
 export * from './psbt';

modules/utxo-core/src/paygo/ExtractAddressPayGoAttestation.ts renamed to modules/utxo-core/src/paygo/parsePayGoAttestation.ts

@@ -21,7 +21,11 @@ const EntropyLen = 64;
  * @param message
  * @param adressProofLength
  */
-export function extractAddressBufferFromPayGoAttestationProof(message: Buffer): Buffer {
+export function parsePayGoAttestation(message: Buffer): {
+  entropy: Buffer;
+  address: Buffer;
+  uuid: Buffer;
+} {
   if (message.length <= PrefixLength + EntropyLen + UuidBufferLength) {
     throw new Error('PayGo attestation proof is too short to contain a valid address');
   }
@@ -34,12 +38,14 @@ export function extractAddressBufferFromPayGoAttestationProof(message: Buffer):
   // https://en.bitcoin.it/wiki/Protocol_documentation
   const varInt = bufferutils.varuint.decode(message, offset);
   assert(varInt);
-  offset += 1;
+  offset += bufferutils.varuint.decode.bytes;
 
-  const addressLength = varInt - EntropyLen - UuidBufferLength;
+  const entropy = message.subarray(offset, offset + EntropyLen);
   offset += EntropyLen;
+  const address = message.subarray(offset, message.length - UuidBufferLength);
+  offset += address.length;
+  const uuid = message.subarray(message.length - UuidBufferLength);
 
-  // we return what the Buffer subarray from the offset (beginning of address)
-  // to the end of the address index in the buffer.
-  return message.subarray(offset, offset + addressLength);
+  // we break up the original message and retuen the entropy, address and uuid in their buffers
+  return { entropy, address, uuid };
 }

modules/utxo-core/test/paygo/ExtractAddressPayGoAttestation.ts renamed to modules/utxo-core/test/paygo/parsePayGoAttestation.ts

@@ -1,6 +1,6 @@
 import * as assert from 'assert';
 
-import { extractAddressBufferFromPayGoAttestationProof } from '../../src/paygo';
+import { parsePayGoAttestation } from '../../src/paygo';
 import { generatePayGoAttestationProof } from '../../src/testutil';
 
 const addressFromPubKeyBase58 = 'bitgoAddressToExtract';
@@ -12,31 +12,35 @@ describe('extractAddressBufferFromPayGoAttestationProof', () => {
       '00000000-0000-0000-0000-000000000000',
       bufferAddressPubKeyB58
     );
-    const addressFromProof = extractAddressBufferFromPayGoAttestationProof(paygoAttestationProof);
-    assert.deepStrictEqual(Buffer.compare(addressFromProof, bufferAddressPubKeyB58), 0);
+    const { entropy, address, uuid } = parsePayGoAttestation(paygoAttestationProof);
+    assert.deepStrictEqual(Buffer.compare(address, bufferAddressPubKeyB58), 0);
+    assert.deepStrictEqual(uuid.toString(), '00000000-0000-0000-0000-000000000000');
+    assert.deepStrictEqual(entropy.length, 64);
   });
 
   it('should extract the paygo address paygo attestation proof given a non nilUUID', () => {
     const paygoAttestationProof = generatePayGoAttestationProof(
       '12345678-1234-4567-6890-231928472123',
       bufferAddressPubKeyB58
     );
-    const addressFromProof = extractAddressBufferFromPayGoAttestationProof(paygoAttestationProof);
-    assert.deepStrictEqual(Buffer.compare(addressFromProof, bufferAddressPubKeyB58), 0);
+    const { entropy, address, uuid } = parsePayGoAttestation(paygoAttestationProof);
+    assert.deepStrictEqual(Buffer.compare(address, bufferAddressPubKeyB58), 0);
+    assert.deepStrictEqual(uuid.toString(), '12345678-1234-4567-6890-231928472123');
+    assert.deepStrictEqual(entropy.length, 64);
   });
 
   it('should not extract the correct address given a uuid of wrong format', () => {
     const paygoAttestationProof = generatePayGoAttestationProof(
       '000000000000000-000000-0000000-000000-0000000000000000',
       bufferAddressPubKeyB58
     );
-    const addressFromProof = extractAddressBufferFromPayGoAttestationProof(paygoAttestationProof);
-    assert.notDeepStrictEqual(Buffer.compare(addressFromProof, bufferAddressPubKeyB58), 0);
+    const { address } = parsePayGoAttestation(paygoAttestationProof);
+    assert.notDeepStrictEqual(Buffer.compare(address, bufferAddressPubKeyB58), 0);
   });
 
   it('should throw an error if the paygo attestation proof is too short', () => {
     assert.throws(
-      () => extractAddressBufferFromPayGoAttestationProof(Buffer.from('shortproof-shrug')),
+      () => parsePayGoAttestation(Buffer.from('shortproof-shrug')),
       'PayGo attestation proof is too short to contain a valid address.'
     );
   });