From b578fdb40b77e888e1e36ce5d816c4dfbdb0f0b4 Mon Sep 17 00:00:00 2001
From: Matthew Zipkin <pinheadmz@pm.me>
Date: Sat, 25 Oct 2025 09:03:00 -0400
Subject: [PATCH] commander: derive port and signet magic bytes automagically

---
 .../charts/bitcoincore/templates/pod.yaml     |  1 +
 resources/scenarios/commander.py              | 26 +++++++++++++++++--
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/resources/charts/bitcoincore/templates/pod.yaml b/resources/charts/bitcoincore/templates/pod.yaml
index f7e154147..f8b8d1de1 100644
--- a/resources/charts/bitcoincore/templates/pod.yaml
+++ b/resources/charts/bitcoincore/templates/pod.yaml
@@ -8,6 +8,7 @@ metadata:
         {{- toYaml . | nindent 4 }}
     {{- end }}
     chain: {{ .Values.global.chain }}
+    P2PPort: "{{ index .Values.global .Values.global.chain "P2PPort" }}"
     RPCPort: "{{ index .Values.global .Values.global.chain "RPCPort" }}"
     ZMQTxPort: "{{ .Values.global.ZMQTxPort }}"
     ZMQBlockPort: "{{ .Values.global.ZMQBlockPort }}"
diff --git a/resources/scenarios/commander.py b/resources/scenarios/commander.py
index cfdcfd53d..5d8badf9e 100644
--- a/resources/scenarios/commander.py
+++ b/resources/scenarios/commander.py
@@ -28,11 +28,12 @@
     CTxOut,
     from_binary,
     from_hex,
+    hash256,
     ser_string,
     ser_uint256,
     tx_from_hex,
 )
-from test_framework.p2p import NetworkThread
+from test_framework.p2p import MAGIC_BYTES, NetworkThread
 from test_framework.psbt import (
     PSBT,
     PSBT_GLOBAL_UNSIGNED_TX,
@@ -94,6 +95,7 @@
                 "tank": pod.metadata.name,
                 "namespace": pod.metadata.namespace,
                 "chain": pod.metadata.labels["chain"],
+                "p2pport": int(pod.metadata.labels["P2PPort"]),
                 "rpc_host": pod.status.pod_ip,
                 "rpc_port": int(pod.metadata.labels["RPCPort"]),
                 "rpc_user": "user",
@@ -263,6 +265,7 @@ def setup(self):
             )
             node.rpc_connected = True
             node.init_peers = int(tank["init_peers"])
+            node.p2pport = tank["p2pport"]
 
             self.nodes.append(node)
             self.tanks[tank["tank"]] = node
@@ -295,6 +298,25 @@ def setup(self):
 
         self.success = TestStatus.PASSED
 
+        if len(self.nodes) > 0 and self.nodes[0].chain == "signet":
+            # There's no garuntee that any nodes are responsive
+            # but we only need one to figure out the network magic bytes
+            for node in self.nodes:
+                try:
+                    # Times out after 60 seconds (!)
+                    template = node.getblocktemplate({"rules": ["segwit", "signet"]})
+                    challenge = template["signet_challenge"]
+                    challenge_bytes = bytes.fromhex(challenge)
+                    data = len(challenge_bytes).to_bytes() + challenge_bytes
+                    digest = hash256(data)
+                    MAGIC_BYTES["signet"] = digest[0:4]
+                    self.log.info(
+                        f"Got signet network magic bytes from {node.tank}: {MAGIC_BYTES['signet'].hex()}"
+                    )
+                    break
+                except Exception as e:
+                    self.log.info(f"Failed to get signet network magic bytes from {node.tank}: {e}")
+
     def parse_args(self):
         # Only print "outer" args from parent class when using --help
         help_parser = argparse.ArgumentParser(usage="%(prog)s [options]")
@@ -482,7 +504,7 @@ def connect_nodes(self, a, b, *, peer_advertises_v2=None, wait_for_connect: bool
         to_connection = self.nodes[b]
         from_num_peers = 1 + len(from_connection.getpeerinfo())
         to_num_peers = 1 + len(to_connection.getpeerinfo())
-        ip_port = self.nodes[b].rpchost + ":18444"
+        ip_port = f"{self.nodes[b].rpchost}:{self.nodes[b].p2pport}"
 
         if peer_advertises_v2 is None:
             peer_advertises_v2 = self.options.v2transport