multi: make anchor tx version configurable and validate v3 with bitcoind

.github/actions/setup-bitcoind/action.yml

@@ -0,0 +1,34 @@
+name: "Setup bitcoind"
+description: "Install a pinned Bitcoin Core release for integration tests"
+inputs:
+  version:
+    description: "Bitcoin Core version to install"
+    required: false
+    default: "30.2"
+
+runs:
+  using: "composite"
+
+  steps:
+    - name: install bitcoind ${{ inputs.version }}
+      shell: bash
+      run: |
+        set -euo pipefail
+
+        if command -v bitcoind >/dev/null 2>&1; then
+          bitcoind --version
+          exit 0
+        fi
+
+        VERSION="${{ inputs.version }}"
+        ARCHIVE="bitcoin-${VERSION}-x86_64-linux-gnu.tar.gz"
+        URL="https://bitcoincore.org/bin/bitcoin-core-${VERSION}/${ARCHIVE}"
+        WORKDIR="$(mktemp -d)"
+
+        curl --fail --location --retry 5 --output "${WORKDIR}/${ARCHIVE}" "${URL}"
+        tar -C "${WORKDIR}" -xzf "${WORKDIR}/${ARCHIVE}"
+
+        sudo install -m 0755 "${WORKDIR}/bitcoin-${VERSION}/bin/bitcoind" /usr/local/bin/bitcoind
+        sudo install -m 0755 "${WORKDIR}/bitcoin-${VERSION}/bin/bitcoin-cli" /usr/local/bin/bitcoin-cli
+
+        bitcoind --version

.github/workflows/main.yaml

@@ -388,6 +388,9 @@ jobs:
           name: itest-binaries
           path: itest
 
+      - name: Setup bitcoind
+        uses: ./.github/actions/setup-bitcoind
+
       - name: Initialize environment
         run: |
           chmod +x itest/itest.test itest/btcd-itest itest/lnd-itest itest/tapd-itest itest/chantools/chantools
@@ -480,6 +483,9 @@ jobs:
           name: itest-binaries
           path: itest
 
+      - name: Setup bitcoind
+        uses: ./.github/actions/setup-bitcoind
+
       - name: Initialize environment
         run: |
           chmod +x itest/itest.test itest/btcd-itest itest/lnd-itest itest/tapd-itest itest/chantools/chantools
@@ -553,6 +559,40 @@ jobs:
           format: 'golang'
           parallel: true
 
+  integration-test-v3:
+    name: run v3 anchor itest
+    runs-on: ubuntu-latest
+    steps:
+      - name: git checkout
+        uses: actions/checkout@v5
+
+      - name: Setup go ${{ env.GO_VERSION }}
+        uses: ./.github/actions/setup-go
+        with:
+          go-version: '${{ env.GO_VERSION }}'
+          key-prefix: itest-v3
+
+      - name: Setup bitcoind
+        uses: ./.github/actions/setup-bitcoind
+
+      - name: Initialize environment
+        run: mkdir -p ~/.aperture
+
+      - name: run v3 anchor itest
+        run: make itest-v3
+
+      - name: Zip log files on failure
+        if: ${{ failure() }}
+        run: 7z a logs-itest-v3.zip itest/regtest/*.log itest/regtest/logs-tranche*/*.log || true
+
+      - name: Upload log files on failure
+        uses: actions/upload-artifact@v7
+        if: ${{ failure() }}
+        with:
+          name: logs-itest-v3
+          path: logs-itest-v3.zip
+          retention-days: 5
+
   # Custom channel integration tests.
   custom-channels-itest:
     name: run custom channels itests
@@ -572,6 +612,9 @@ jobs:
           name: itest-binaries
           path: itest
 
+      - name: Setup bitcoind
+        uses: ./.github/actions/setup-bitcoind
+
       - name: Initialize environment
         run: |
           chmod +x itest/tapd-integrated-itest itest/btcd-itest itest/custom_channels/itest-cc.test

Makefile

@@ -280,6 +280,9 @@ itest-cc-parallel: build-itest build-itest-cc-binary clean-cc-itest-logs
 
 itest: build-itest itest-only
 
+itest-v3:
+	$(MAKE) itest backend=bitcoind icase=anchor_tx_version_v3
+
 itest-trace: build-itest itest-only-trace
 
 itest-only: aperture-dir clean-itest-logs

asset/group_key_test.go

@@ -333,7 +333,7 @@ func TestNonSpendableLeafScript(t *testing.T) {
 
 			// Finally, we'll make the dummy spend transaction, and
 			// the output script that we'll attempt to spend.
-			spendTx := wire.NewMsgTx(1)
+			spendTx := wire.NewMsgTx(3)
 			spendTx.AddTxIn(&wire.TxIn{})
 
 			leafScript, err := txscript.PayToTaprootScript(

asset/mock.go

@@ -313,6 +313,11 @@ func virtualGenesisTx(newAsset *Asset) (*wire.MsgTx, error) {
 
 	// With our single input and output mapped, we're ready to construct our
 	// virtual transaction.
+	//
+	// IMPORTANT: The virtual transaction version must remain at v2 for
+	// backwards compatibility. Changing the version would invalidate all
+	// existing asset witness signatures. Only the anchor (real Bitcoin)
+	// transactions use v3.
 	virtualTx := wire.NewMsgTx(2)
 	virtualTx.AddTxIn(txIn)
 	virtualTx.AddTxOut(txOut)

authmailbox/client_test.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/btcsuite/btclog/v2"
+	"github.com/lightninglabs/taproot-assets/asset"
 	"github.com/lightninglabs/taproot-assets/fn"
 	"github.com/lightninglabs/taproot-assets/internal/test"
 	"github.com/lightninglabs/taproot-assets/proof"
@@ -169,6 +170,32 @@ func TestServerClientAuthAndRestart(t *testing.T) {
 	t.Cleanup(func() {
 		require.NoError(t, multiSub.Stop())
 	})
+	assertMultiSubConnected := func(targetKeys ...keychain.KeyDescriptor) {
+		t.Helper()
+
+		serverURL := url.URL{Host: clientCfg.ServerAddress}
+		require.Eventually(t, func() bool {
+			multiSub.RLock()
+			defer multiSub.RUnlock()
+
+			client, ok := multiSub.clients[serverURL]
+			if !ok {
+				return false
+			}
+
+			for _, targetKey := range targetKeys {
+				key := asset.ToSerialized(targetKey.PubKey)
+				subscription, ok := client.subscriptions[key]
+				if !ok || !subscription.IsSubscribed() {
+					return false
+				}
+			}
+
+			return true
+		}, testTimeout, testMinBackoff)
+	}
+	assertMultiSubConnected(clientKey1, clientKey2)
+
 	msgChan := multiSub.MessageChan()
 	readMultiSub := func(targetID ...uint64) {
 		t.Helper()
@@ -221,6 +248,7 @@ func TestServerClientAuthAndRestart(t *testing.T) {
 	harness.Start(t)
 	client1.assertConnected(t)
 	client2.assertConnected(t)
+	assertMultiSubConnected(clientKey1, clientKey2)
 
 	// Let's send another message to all clients.
 	msg2 := &Message{

authmailbox/receive_subscription.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"math"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/btcsuite/btclog/v2"
@@ -61,6 +62,7 @@ type receiveSubscription struct {
 	serverStream clientStream
 	streamMutex  sync.RWMutex
 	streamCancel func()
+	subscribed   atomic.Bool
 
 	authOkChan chan struct{}
 	msgChan    chan<- *ReceivedMessages
@@ -198,10 +200,7 @@ func (s *receiveSubscription) wait(backoff time.Duration) error {
 // IsSubscribed returns true if at least one account is in an active state and
 // the subscription stream to the server was established successfully.
 func (s *receiveSubscription) IsSubscribed() bool {
-	s.streamMutex.RLock()
-	defer s.streamMutex.RUnlock()
-
-	return s.serverStream != nil
+	return s.subscribed.Load()
 }
 
 // connectServerStream opens the initial connection to the server for the stream
@@ -412,6 +411,8 @@ func (s *receiveSubscription) readIncomingStream(ctx context.Context) {
 		// The server confirms the account subscription. Nothing for us
 		// to do here.
 		case *respTypeAuthSuccess:
+			s.subscribed.Store(true)
+
 			// Inform the subscription about the arrived auth
 			// confirmation.
 			select {
@@ -476,6 +477,7 @@ func (s *receiveSubscription) closeStream(ctx context.Context) error {
 
 	s.streamMutex.Lock()
 	defer s.streamMutex.Unlock()
+	s.subscribed.Store(false)
 
 	if s.streamCancel != nil {
 		s.streamCancel()

docs/release-notes/release-notes-0.8.0.md

@@ -264,6 +264,11 @@
   Add pagination support (offset, limit, direction) to the `ListAssets` RPC
   endpoint.
 
+- [PR#1857](https://github.com/lightninglabs/taproot-assets/pull/1857)
+  Add RPC support for selecting the version of newly created anchor
+  transactions in minting, send, and virtual-PSBT anchoring flows while
+  keeping v2 as the default.
+
 ## tapcli Updates
 
 - [PR#1995](https://github.com/lightninglabs/taproot-assets/pull/1995)
@@ -308,6 +313,10 @@
 
 ## Testing
 
+- [PR#1857](https://github.com/lightninglabs/taproot-assets/pull/1857)
+  Add a dedicated bitcoind-backed integration lane that verifies explicit
+  v3 anchor transactions end to end.
+
 - [Wallet Backup Integration Tests](https://github.com/lightninglabs/taproot-assets/pull/1980):
   Add two integration tests for wallet backup covering genesis backup/restore,
   idempotent import, all three backup modes with size comparison, post-restore