devtools: add privkey+hash printing to mkcommit/mkgossip

We updated the protocol spec tests to verify a sig from a hash
and a private key; this updates mkcommit + mkgossip utilities
to print out the procotol compatible SIG() notation for all signatures.

--verbose will print a computed signature and more data as well.

Also adds --verbose flag to mkgossip.

Changelog-None

bitcoin/signature.c

@@ -107,13 +107,14 @@ void sign_hash(const struct privkey *privkey,
 					  privkey->secret.data, NULL, extra_entropy);
 		((u32 *)extra_entropy)[0]++;
 	} while (!sig_has_low_r(s));
+
 	assert(ok);
 }
 
-static void bitcoin_tx_hash_for_sig(const struct bitcoin_tx *tx, unsigned int in,
-				    const u8 *script,
-				    enum sighash_type sighash_type,
-				    struct sha256_double *dest)
+void bitcoin_tx_hash_for_sig(const struct bitcoin_tx *tx, unsigned int in,
+			     const u8 *script,
+			     enum sighash_type sighash_type,
+			     struct sha256_double *dest)
 {
 	int ret;
 	u8 value[9];

bitcoin/signature.h

@@ -46,6 +46,20 @@ struct bitcoin_signature {
 	enum sighash_type sighash_type;
 };
 
+/**
+ * bitcoin_tx_hash_for_sig - produce hash for a transaction
+ *
+ * @tx - tx to hash
+ * @in - index that this 'hash' is for
+ * @script - script for the index that's being 'hashed for'
+ * @sighash_type - sighash_type to hash for
+ * @dest - hash result
+ */
+void bitcoin_tx_hash_for_sig(const struct bitcoin_tx *tx, unsigned int in,
+			     const u8 *script,
+			     enum sighash_type sighash_type,
+			     struct sha256_double *dest);
+
 /**
  * sign_hash - produce a raw secp256k1 signature (with low R value).
  * @p: secret key

devtools/mkcommit.c

@@ -162,16 +162,6 @@ static int parse_config(char *argv[],
 	return argnum;
 }
 
-static char *sig_as_hex(const struct bitcoin_signature *sig)
-{
-	u8 compact_sig[64];
-
-	secp256k1_ecdsa_signature_serialize_compact(secp256k1_ctx,
-						    compact_sig,
-						    &sig->s);
-	return tal_hexstr(NULL, compact_sig, sizeof(compact_sig));
-}
-
 static int parse_htlc(char *argv[],
 		      struct added_htlc **htlcs,
 		      enum htlc_state **htlc_states,
@@ -224,6 +214,33 @@ static const struct preimage *preimage_of(const struct sha256 *hash,
 	abort();
 }
 
+static char *sig_as_hex(const struct bitcoin_signature *sig)
+{
+	u8 compact_sig[64];
+
+	secp256k1_ecdsa_signature_serialize_compact(secp256k1_ctx,
+						    compact_sig,
+						    &sig->s);
+	return tal_hexstr(NULL, compact_sig, sizeof(compact_sig));
+}
+
+
+static char *sig_notation(const struct sha256_double *hash,
+			  const struct privkey *privkey,
+			  const struct bitcoin_signature *sig)
+{
+	const char *pstr = tal_hexstr(NULL, privkey->secret.data, sizeof(privkey->secret.data));
+	const char *hstr = type_to_string(NULL, struct sha256_double, hash);
+
+	if (verbose)
+		return tal_fmt(NULL,
+			       "SIG(%s:%s)\n privkey: %s\n tx_hash: %s\n"
+			       " sig: %s",
+			       pstr, hstr, pstr, hstr, sig_as_hex(sig));
+
+	return tal_fmt(NULL, "SIG(%s:%s)", pstr, hstr);
+}
+
 int main(int argc, char *argv[])
 {
 	struct secrets local, remote;
@@ -252,6 +269,7 @@ int main(int argc, char *argv[])
 	struct privkey local_htlc_privkey, remote_htlc_privkey;
 	struct pubkey local_htlc_pubkey, remote_htlc_pubkey;
 	bool option_static_remotekey = false;
+	struct sha256_double hash;
 
 	setup_locale();
 	chainparams = chainparams_for_network("bitcoin");
@@ -386,26 +404,33 @@ int main(int argc, char *argv[])
 				&local_per_commit_point, commitnum, LOCAL);
 
 	printf("## local_commitment\n"
-	       "# input amount %s, funding_wscript %s, key %s\n",
+	       "# input amount %s, funding_wscript %s, pubkey %s\n",
 	       type_to_string(NULL, struct amount_sat, &funding_amount),
 	       tal_hex(NULL, funding_wscript),
 	       type_to_string(NULL, struct pubkey, &funding_localkey));
 	printf("# unsigned local commitment tx: %s\n",
 	       tal_hex(NULL, linearize_tx(NULL, local_txs[0])));
 
+	/* Get the hash out, for printing */
+	bitcoin_tx_hash_for_sig(local_txs[0], 0, funding_wscript,
+				SIGHASH_ALL, &hash);
 	sign_tx_input(local_txs[0], 0, NULL, funding_wscript,
 		      &local.funding_privkey,
 		      &funding_localkey,
 		      SIGHASH_ALL,
 		      &local_sig);
-	printf("localsig_on_local: %s\n", sig_as_hex(&local_sig));
+	printf("localsig_on_local: %s\n", sig_notation(&hash,
+						       &local.funding_privkey,
+						       &local_sig));
 
 	sign_tx_input(local_txs[0], 0, NULL, funding_wscript,
 		      &remote.funding_privkey,
 		      &funding_remotekey,
 		      SIGHASH_ALL,
 		      &remote_sig);
-	printf("remotesig_on_local: %s\n", sig_as_hex(&remote_sig));
+	printf("remotesig_on_local: %s\n", sig_notation(&hash,
+							&remote.funding_privkey,
+							&remote_sig));
 
 	witness =
 		bitcoin_witness_2of2(NULL, &local_sig, &remote_sig,
@@ -452,6 +477,9 @@ int main(int argc, char *argv[])
 			= tal_dup(local_txs[1+i], struct amount_sat, &amt);
 
 		printf("# wscript: %s\n", tal_hex(NULL, wscripts[1+i]));
+
+		bitcoin_tx_hash_for_sig(local_txs[1+i], 0, wscripts[1+i],
+					SIGHASH_ALL, &hash);
 		sign_tx_input(local_txs[1+i], 0, NULL, wscripts[1+i],
 			      &local_htlc_privkey, &local_htlc_pubkey,
 			      SIGHASH_ALL, &local_htlc_sig);
@@ -459,9 +487,9 @@ int main(int argc, char *argv[])
 			      &remote_htlc_privkey, &remote_htlc_pubkey,
 			      SIGHASH_ALL, &remote_htlc_sig);
 		printf("localsig_on_local output %zu: %s\n",
-		       i, sig_as_hex(&local_htlc_sig));
+		       i, sig_notation(&hash, &local_htlc_privkey, &local_htlc_sig));
 		printf("remotesig_on_local output %zu: %s\n",
-		       i, sig_as_hex(&remote_htlc_sig));
+		       i, sig_notation(&hash, &remote_htlc_privkey, &remote_htlc_sig));
 
 		if (htlc_owner(htlcmap[i]) == LOCAL)
 			witness = bitcoin_witness_htlc_timeout_tx(NULL,
@@ -496,19 +524,25 @@ int main(int argc, char *argv[])
 	printf("# unsigned remote commitment tx: %s\n",
 	       tal_hex(NULL, linearize_tx(NULL, remote_txs[0])));
 
+	bitcoin_tx_hash_for_sig(remote_txs[0], 0, funding_wscript,
+				SIGHASH_ALL, &hash);
 	sign_tx_input(remote_txs[0], 0, NULL, funding_wscript,
 		      &local.funding_privkey,
 		      &funding_localkey,
 		      SIGHASH_ALL,
 		      &local_sig);
-	printf("localsig_on_remote: %s\n", sig_as_hex(&local_sig));
+	printf("localsig_on_remote: %s\n", sig_notation(&hash,
+							&local.funding_privkey,
+							&local_sig));
 
 	sign_tx_input(remote_txs[0], 0, NULL, funding_wscript,
 		      &remote.funding_privkey,
 		      &funding_remotekey,
 		      SIGHASH_ALL,
 		      &remote_sig);
-	printf("remotesig_on_remote: %s\n", sig_as_hex(&remote_sig));
+	printf("remotesig_on_remote: %s\n", sig_notation(&hash,
+							 &remote.funding_privkey,
+							 &remote_sig));
 
 	witness =
 		bitcoin_witness_2of2(NULL, &local_sig, &remote_sig,
@@ -555,6 +589,8 @@ int main(int argc, char *argv[])
 			= tal_dup(remote_txs[1+i], struct amount_sat, &amt);
 
 		printf("# wscript: %s\n", tal_hex(NULL, wscripts[1+i]));
+		bitcoin_tx_hash_for_sig(remote_txs[1+i], 0, wscripts[1+i],
+					SIGHASH_ALL, &hash);
 		sign_tx_input(remote_txs[1+i], 0, NULL, wscripts[1+i],
 			      &local_htlc_privkey, &local_htlc_pubkey,
 			      SIGHASH_ALL, &local_htlc_sig);
@@ -562,9 +598,9 @@ int main(int argc, char *argv[])
 			      &remote_htlc_privkey, &remote_htlc_pubkey,
 			      SIGHASH_ALL, &remote_htlc_sig);
 		printf("localsig_on_remote output %zu: %s\n",
-		       i, sig_as_hex(&local_htlc_sig));
+		       i, sig_notation(&hash, &local_htlc_privkey, &local_htlc_sig));
 		printf("remotesig_on_remote output %zu: %s\n",
-		       i, sig_as_hex(&remote_htlc_sig));
+		       i, sig_notation(&hash, &remote_htlc_privkey, &remote_htlc_sig));
 
 		if (htlc_owner(htlcmap[i]) == REMOTE)
 			witness = bitcoin_witness_htlc_timeout_tx(NULL,

devtools/mkgossip.c

@@ -14,13 +14,17 @@
 #include <bitcoin/tx.h>
 #include <ccan/crc32c/crc32c.h>
 #include <ccan/err/err.h>
+#include <ccan/opt/opt.h>
 #include <ccan/str/hex/hex.h>
 #include <common/gossip_constants.h>
+#include <common/type_to_string.h>
 #include <common/utils.h>
 #include <inttypes.h>
 #include <wire/gen_peer_wire.h>
 #include <stdio.h>
 
+static bool verbose = false;
+
 struct update_opts {
 	u32 timestamp;
 	u32 cltv_expiry_delta;
@@ -79,6 +83,26 @@ static char *sig_as_hex(const secp256k1_ecdsa_signature *sig)
 	return tal_hexstr(NULL, compact_sig, sizeof(compact_sig));
 }
 
+static char *sig_notation(const struct privkey *privkey,
+			  struct sha256_double *hash,
+			  const secp256k1_ecdsa_signature *sig)
+{
+	const char *pstr = tal_hexstr(NULL, privkey->secret.data,
+				      sizeof(privkey->secret.data));
+	const char *hstr =
+		type_to_string(NULL, struct sha256_double, hash);
+
+	if (verbose)
+		return tal_fmt(NULL,
+			       "SIG(%s:%s)\n"
+			       "   -- privkey= %s\n"
+			       "   -- tx_hash= %s\n"
+			       "   -- computed_sig= %s",
+			       pstr, hstr, pstr, hstr, sig_as_hex(sig));
+
+	return tal_fmt(NULL, "SIG(%s:%s)", pstr, hstr);
+}
+
 /* BOLT #7:
  *
  * The checksum of a `channel_update` is the CRC32C checksum as specified in
@@ -145,7 +169,7 @@ static void print_update(const struct bitcoin_blkid *chainhash,
 	sign_hash(privkey, &hash, &sig);
 
 	printf("type=channel_update\n");
-	printf("   signature=%s\n", sig_as_hex(&sig));
+	printf("   signature=%s\n", sig_notation(privkey, &hash, &sig));
 	printf("   chain_hash=%s\n", tal_hexstr(NULL, chainhash, sizeof(*chainhash)));
 	printf("   short_channel_id=%s\n", short_channel_id_to_str(NULL, scid));
 	printf("   timestamp=%u\n", opts->timestamp);
@@ -189,7 +213,7 @@ static void print_nannounce(const struct node_id *nodeid,
 	sign_hash(privkey, &hash, &sig);
 
 	printf("type=node_announcement\n");
-	printf("   signature=%s\n", sig_as_hex(&sig));
+	printf("   signature=%s\n", sig_notation(privkey, &hash, &sig));
 	printf("   features=%s\n", tal_hex(NULL, NULL));
 	printf("   timestamp=%u\n", opts->timestamp);
 	printf("   node_id=%s\n", node_id_to_hexstr(NULL, nodeid));
@@ -220,7 +244,7 @@ int main(int argc, char *argv[])
 	secp256k1_ctx = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY |
 						 SECP256K1_CONTEXT_SIGN);
 
-	if (argc != 8 + 7 * 2)
+	if (argc < 8 + 7 * 2)
 		errx(1, "Usage: mkgossip <scid> <chainhash> <node-privkey1> <node-privkey2> <node1-funding-privkey> <node2-funding-privkey> <features-hex> update-opts-1 update-opts-2\n"
 			"Where <update-opts> is:\n"
 			"   <timestamp>\n"
@@ -231,6 +255,11 @@ int main(int argc, char *argv[])
 			"   <htlc_maximum_msat-or-empty>\n"
 			"   <hex-addrstr>");
 
+	opt_register_noarg("-v|--verbose", opt_set_bool, &verbose,
+			   "Increase verbosity");
+
+	opt_parse(&argc, argv, opt_log_stderr_exit);
+
 	argnum = 1;
 	if (!short_channel_id_from_str(argv[argnum], strlen(argv[argnum]), &scid))
 		errx(1, "Bad scid");
@@ -297,10 +326,14 @@ int main(int argc, char *argv[])
 	sign_hash(&funding_privkey[1], &hash, &bitcoinsig[1]);
 
 	printf("type=channel_announcement\n");
-	printf("   node_signature_1=%s\n", sig_as_hex(&nodesig[lesser_key]));
-	printf("   node_signature_2=%s\n", sig_as_hex(&nodesig[!lesser_key]));
-	printf("   bitcoin_signature_1=%s\n", sig_as_hex(&bitcoinsig[lesser_key]));
-	printf("   bitcoin_signature_2=%s\n", sig_as_hex(&bitcoinsig[!lesser_key]));
+	printf("   node_signature_1=%s\n",
+	       sig_notation(&node_privkey[lesser_key], &hash, &nodesig[lesser_key]));
+	printf("   node_signature_2=%s\n",
+	       sig_notation(&node_privkey[!lesser_key], &hash, &nodesig[!lesser_key]));
+	printf("   bitcoin_signature_1=%s\n",
+	       sig_notation(&funding_privkey[lesser_key], &hash, &bitcoinsig[lesser_key]));
+	printf("   bitcoin_signature_2=%s\n",
+	       sig_notation(&funding_privkey[!lesser_key], &hash, &bitcoinsig[!lesser_key]));
 	printf("   features=%s\n", tal_hex(NULL, features));
 	printf("   chain_hash=%s\n", tal_hexstr(NULL, &chainhash, sizeof(chainhash)));
 	printf("   short_channel_id=%s\n", short_channel_id_to_str(NULL, &scid));