From f45ab2f25fe44b3ec6c2ea5a139409e731f3b409 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hern=C3=A1n=20Di=20Pietro?= <hernan.di.pietro@gmail.com>
Date: Fri, 19 Nov 2021 16:00:24 -0300
Subject: [PATCH] FIX:  Signature verification WORKS.

---
 teal/wormhole/pyteal/vaa-verify.py | 30 +++++++++++++++++++-----------
 test/testlib.js                    |  4 +++-
 2 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/teal/wormhole/pyteal/vaa-verify.py b/teal/wormhole/pyteal/vaa-verify.py
index e54e32a3..e7a9515f 100644
--- a/teal/wormhole/pyteal/vaa-verify.py
+++ b/teal/wormhole/pyteal/vaa-verify.py
@@ -31,6 +31,7 @@ SLOTID_RECOVERED_PK_Y = 241
 def sig_check(signatures, digest, keys):
     si = ScratchVar(TealType.uint64)
     ki = ScratchVar(TealType.uint64)
+    i = ScratchVar(TealType.uint64)
     rec_pk_x = ScratchVar(TealType.bytes, SLOTID_RECOVERED_PK_X)
     rec_pk_y = ScratchVar(TealType.bytes, SLOTID_RECOVERED_PK_Y)
 
@@ -39,34 +40,41 @@ def sig_check(signatures, digest, keys):
             rec_pk_x.store(Bytes("")),
             rec_pk_y.store(Bytes("")),
             For(Seq([
+                i.store(Int(0)),
                 si.store(Int(0)),
                 ki.store(Int(0))
             ]),
                 si.load() < Len(signatures),
                 Seq([
                     si.store(si.load() + Int(66)),
-                    ki.store(ki.load() + Int(32)),
+                    ki.store(ki.load() + Int(20)),
+                    i.store(i.load() + Int(1)),
                 ])).Do(
                     Seq([
+                        # Index must be sequential
+
+                        Assert(Btoi(Extract(signatures, si.load(), Int(1))) == 
+                             i.load() + (Txn.group_index() * Int(MAX_SIGNATURES_PER_VERIFICATION_STEP))),
+
                         InlineAssembly(
                             "ecdsa_pk_recover Secp256k1",
-                            digest,
-                            Btoi(Extract(signatures, si.load() + Int(64), Int(1))),
-                            Extract(signatures, si.load() + Int(32), Int(32)),
-                            Extract(signatures, si.load(), Int(32)),
+                            Keccak256(digest),
+                            Btoi(Extract(signatures, si.load() + Int(65), Int(1))),
+                            Extract(signatures, si.load() + Int(1), Int(32)),       # R
+                            Extract(signatures, si.load() + Int(33), Int(32)),      # S
                             type=TealType.none),
 
                         # returned values in stack, pass to scratch-vars
 
-                        InlineAssembly("store " + str(SLOTID_RECOVERED_PK_X)),
                         InlineAssembly("store " + str(SLOTID_RECOVERED_PK_Y)),
+                        InlineAssembly("store " + str(SLOTID_RECOVERED_PK_X)),
 
                         # Generate Ethereum-type public key, compare with guardian key.
 
                         Assert(
-                            Extract(keys, ki.load(), Int(32)) ==
-                            Extract(Keccak256(Concat(rec_pk_x.load(),
-                                    rec_pk_y.load())), Int(0), Int(20))
+                            Extract(keys, ki.load(), Int(20)) ==
+                            Substring(Keccak256(Concat(rec_pk_x.load(),
+                                    rec_pk_y.load())), Int(12), Int(32))
                         )
                     ])
 
@@ -79,7 +87,7 @@ def sig_check(signatures, digest, keys):
 
 """
 * Let N be the number of signatures per verification step, for the TX(i) in group, we verify signatures [j..k] where j = i*N, k = j+(N-1)
-* Input 0 is signatures [j..k] to verify as LogicSigArgs.
+* Input 0 is signatures [j..k] to verify as LogicSigArgs. (Format is GuardianIndex + signature)
 * Input 1 is signed digest of payload, contained in the note field of the TX in current slot.
 * Input 2 is public keys for guardians [j..k] contained in the first Argument  of the TX in current slot.
 * Input 3 is guardian set size contained in the second argument of the TX in current slot.
@@ -94,7 +102,7 @@ def vaa_verify_program(vaa_processor_app_id):
 
     return Seq([
         Assert(Txn.fee() <= Int(1000)),
-        Assert(Txn.application_args.length() == Int(1)),
+        Assert(Txn.application_args.length() == Int(3)),
         Assert(Len(signatures) == get_sig_count_in_step(
                 Txn.group_index(), Btoi(num_guardians)) * Int(66)),
         Assert(Txn.rekey_to() == Global.zero_address()),
diff --git a/test/testlib.js b/test/testlib.js
index 65ed0c28..21d8fa37 100644
--- a/test/testlib.js
+++ b/test/testlib.js
@@ -43,7 +43,9 @@ class TestLib {
       payload.substr(2)
     ]
 
-    const hash = web3Utils.soliditySha3(web3Utils.soliditySha3('0x' + body.join('')))
+    const hash = web3Utils.keccak256('0x' + body.join(''))
+
+    console.log('VAA body Hash: ', hash)
 
     let signatures = ''