From aa6f13e524260c5c5630ed66465e216f3217629e Mon Sep 17 00:00:00 2001
From: Orbital <orbitalturtle@protonmail.com>
Date: Tue, 24 Oct 2023 17:54:25 -0500
Subject: [PATCH] itest: test SignMessage/VerifyMessage tag option
---
itest/lnd_signer_test.go | 70 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 70 insertions(+)
diff --git a/itest/lnd_signer_test.go b/itest/lnd_signer_test.go
index 1372e4502..52b42a29a 100644
--- a/itest/lnd_signer_test.go
+++ b/itest/lnd_signer_test.go
@@ -2,11 +2,13 @@ package itest
import (
"bytes"
+ "context"
"crypto/sha256"
"github.com/btcsuite/btcd/btcec/v2"
"github.com/btcsuite/btcd/btcec/v2/schnorr"
"github.com/btcsuite/btcd/btcutil"
+ "github.com/btcsuite/btcd/chaincfg/chainhash"
"github.com/btcsuite/btcd/txscript"
"github.com/btcsuite/btcd/wire"
"github.com/lightningnetwork/lnd/keychain"
@@ -458,4 +460,72 @@ func runSignVerifyMessage(ht *lntest.HarnessTest, alice *node.HarnessNode) {
}
verifyResp = alice.RPC.VerifyMessageSigner(verifyReq)
require.True(ht, verifyResp.Valid, "failed to verify message")
+
+ // Now let's try signing and verifying a tagged hash.
+ tag := []byte("lightninginvoice_requestsignature")
+
+ signMsgReq = &signrpc.SignMessageReq{
+ Msg: aliceMsg,
+ KeyLoc: keyLoc,
+ SchnorrSig: true,
+ Tag: tag,
+ }
+ signMsgResp = alice.RPC.SignMessageSigner(signMsgReq)
+ customPubKey = deriveCustomizedKey()
+
+ verifyReq = &signrpc.VerifyMessageReq{
+ Msg: aliceMsg,
+ Signature: signMsgResp.Signature,
+ Pubkey: schnorr.SerializePubKey(customPubKey),
+ IsSchnorrSig: true,
+ Tag: tag,
+ }
+ verifyResp = alice.RPC.VerifyMessageSigner(verifyReq)
+ require.True(ht, verifyResp.Valid, "failed to verify message")
+
+ // Verify that both SignMessage and VerifyMessage error if a tag is
+ // provided but the Schnorr option is not set.
+ signMsgReq = &signrpc.SignMessageReq{
+ Msg: aliceMsg,
+ KeyLoc: keyLoc,
+ Tag: tag,
+ }
+
+ expectedErr := "tag can only be used when the Schnorr signature " +
+ "option is set"
+ ctxt := context.Background()
+ _, err := alice.RPC.Signer.SignMessage(ctxt, signMsgReq)
+ require.ErrorContains(ht, err, expectedErr)
+
+ verifyReq = &signrpc.VerifyMessageReq{
+ Msg: aliceMsg,
+ Signature: signMsgResp.Signature,
+ Pubkey: schnorr.SerializePubKey(customPubKey),
+ Tag: tag,
+ }
+
+ _, err = alice.RPC.Signer.VerifyMessage(ctxt, verifyReq)
+ require.ErrorContains(ht, err, expectedErr)
+
+ // Make sure that SignMessage throws an error if a BIP0340 or
+ // TapSighash tag is provided.
+ signMsgReq = &signrpc.SignMessageReq{
+ Msg: aliceMsg,
+ KeyLoc: keyLoc,
+ SchnorrSig: true,
+ Tag: []byte("BIP0340/challenge"),
+ }
+
+ _, err = alice.RPC.Signer.SignMessage(ctxt, signMsgReq)
+ require.ErrorContains(ht, err, "tag cannot have BIP0340 prefix")
+
+ signMsgReq = &signrpc.SignMessageReq{
+ Msg: aliceMsg,
+ KeyLoc: keyLoc,
+ SchnorrSig: true,
+ Tag: chainhash.TagTapSighash,
+ }
+
+ _, err = alice.RPC.Signer.SignMessage(ctxt, signMsgReq)
+ require.ErrorContains(ht, err, "tag cannot be TapSighash")
}