Signmessage

common/hsm_version.h

@@ -28,7 +28,8 @@
  * v6 no secret from get_per_commitment_point: 0cad1790beb3473d64355f4cb4f64daa80c28c8a241998b7ef0223385d7ffff9
  * v6 with sign_bolt12_2 (tweak using node id): 8fcb731279a10af3f95aeb8be1da6b2ced76a1984afa18c5f46a03515d70ea0e
  * v6 with dev_warn_on_overgrind: a273b68e19336073e551c01a78bcd1e1f8cc510da7d0dde3afc45e249f9830cc
-*/
+ * v6 with bip137_sign_message: 4bfe28b02e92aae276b8eca2228e32f32d5dee8d5381639e7364939fa2fa1370
+ */
 #define HSM_MIN_VERSION 5
 #define HSM_MAX_VERSION 6
 #endif /* LIGHTNING_COMMON_HSM_VERSION_H */

contrib/msggen/msggen/schema.json

@@ -32878,6 +32878,99 @@
         }
       ]
     },
+    "signmessagewithkey.json": {
+      "$schema": "../rpc-schema-draft.json",
+      "type": "object",
+      "rpc": "signmessagewithkey",
+      "title": "Command to create a signature using a key from the wallet",
+      "description": [
+        "The **signmessagewithkey** RPC command creates a digital signature of *message* using the key associated with the address provided in the input.",
+        "The signature scheme follows the BIP137 specification."
+      ],
+      "added": "v25.05",
+      "request": {
+        "required": [
+          "message",
+          "address"
+        ],
+        "additionalProperties": false,
+        "properties": {
+          "message": {
+            "type": "string",
+            "description": [
+              "Less than 65536 characters long message to be signed by the node."
+            ]
+          },
+          "address": {
+            "type": "string",
+            "description": [
+              "A Bitcoin accepted type address for lookup in the list of addresses issued to date.",
+              "Only P2WPKH type addresses are supported"
+            ]
+          }
+        }
+      },
+      "response": {
+        "required": [
+          "address",
+          "pubkey",
+          "signature",
+          "base64"
+        ],
+        "additionalProperties": false,
+        "properties": {
+          "address": {
+            "type": "string",
+            "description": [
+              "The bitcoin address used for signing."
+            ]
+          },
+          "pubkey": {
+            "type": "pubkey",
+            "description": [
+              "The public key associated with the bitcoin address provided."
+            ]
+          },
+          "signature": {
+            "type": "hex",
+            "description": [
+              "The signature."
+            ]
+          },
+          "base64": {
+            "type": "string",
+            "description": [
+              "The signature encoded in base64."
+            ]
+          }
+        }
+      },
+      "author": [
+        "Lagrang3 <<[email protected]>> is mainly responsible."
+      ],
+      "see_also": [],
+      "resources": [
+        "Main web site: <https://github.com/ElementsProject/lightning>"
+      ],
+      "examples": [
+        {
+          "request": {
+            "id": "example:signmessagewithkey#1",
+            "method": "signmessagewithkey",
+            "params": {
+              "message": "a test message",
+              "address": "bcrt1qgrh5vtf63mtayzhxwp480aww3j3qfr5qpq65un"
+            }
+          },
+          "response": {
+            "address": "bcrt1qgrh5vtf63mtayzhxwp480aww3j3qfr5qpq65un",
+            "pubkey": "03bc4a456585ba21ba26af4a0e5399ec76410b2e0ca67db0f3bcb2f47b232fa4b0",
+            "signature": "28564edf260a72d991cbb38cf608e293124f8b8f478d13d4544fe27b9d76c65df1284ca395ccdfd3d5f151729ef18f56c028f5f860155d6aa4d0aaaa176a00db01",
+            "base64": "KFZO3yYKctmRy7OM9gjikxJPi49HjRPUVE/ie512xl3xKEyjlczf09XxUXKe8Y9WwCj1+GAVXWqk0KqqF2oA2wE="
+          }
+        }
+      ]
+    },
     "signpsbt.json": {
       "$schema": "../rpc-schema-draft.json",
       "type": "object",

devtools/.gitignore

@@ -20,3 +20,4 @@ topology
 fp16
 rune
 gossmap-compress
+bip137-verifysignature

devtools/Makefile

@@ -1,4 +1,4 @@
-DEVTOOLS := devtools/bolt11-cli devtools/decodemsg devtools/onion devtools/dump-gossipstore devtools/gossipwith devtools/create-gossipstore devtools/mkcommit devtools/mkfunding devtools/mkclose devtools/mkgossip devtools/mkencoded devtools/mkquery devtools/lightning-checkmessage devtools/topology devtools/route devtools/bolt12-cli devtools/encodeaddr devtools/features devtools/fp16 devtools/rune devtools/gossmap-compress
+DEVTOOLS := devtools/bolt11-cli devtools/decodemsg devtools/onion devtools/dump-gossipstore devtools/gossipwith devtools/create-gossipstore devtools/mkcommit devtools/mkfunding devtools/mkclose devtools/mkgossip devtools/mkencoded devtools/mkquery devtools/lightning-checkmessage devtools/topology devtools/route devtools/bolt12-cli devtools/encodeaddr devtools/features devtools/fp16 devtools/rune devtools/gossmap-compress devtools/bip137-verifysignature
 ifeq ($(HAVE_SQLITE3),1)
 DEVTOOLS += devtools/checkchannels
 endif
@@ -99,6 +99,8 @@ devtools/mkquery: $(DEVTOOLS_COMMON_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/t
 
 devtools/lightning-checkmessage: $(DEVTOOLS_COMMON_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o devtools/lightning-checkmessage.o
 
+devtools/bip137-verifysignature: $(DEVTOOLS_COMMON_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o devtools/bip137-verifysignature.o
+
 devtools/route: $(DEVTOOLS_COMMON_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o wire/tlvstream.o common/gossmap.o common/fp16.o common/random_select.o common/route.o common/dijkstra.o devtools/clean_topo.o devtools/route.o
 
 devtools/topology: $(DEVTOOLS_COMMON_OBJS) $(BITCOIN_OBJS) wire/fromwire.o wire/towire.o wire/tlvstream.o common/gossmap.o common/fp16.o common/random_select.o common/dijkstra.o common/route.o devtools/clean_topo.o devtools/topology.o

devtools/bip137-verifysignature.c

@@ -0,0 +1,114 @@
+#include "config.h"
+#include <assert.h>
+#include <bitcoin/base58.h>
+#include <bitcoin/pubkey.h>
+#include <bitcoin/shadouble.h>
+#include <bitcoin/varint.h>
+#include <ccan/err/err.h>
+#include <common/addr.h>
+#include <common/bech32.h>
+#include <common/utils.h>
+#include <secp256k1_recovery.h>
+#include <stdio.h>
+#include <wally_core.h>
+
+static void usage(void)
+{
+	fprintf(stderr,
+		"Usage: bip137-verifysignature message hex-sig [address] [network]\n"
+		"If key does not match, signature is not valid!\n");
+	exit(1);
+}
+
+static char *encode_pubkey_to_p2wpkh_addr(const tal_t *ctx,
+					  const struct pubkey *pubkey,
+					  const struct chainparams *chain)
+{
+	char *out;
+	const char *hrp;
+	struct ripemd160 h160;
+        bool ok;
+	hrp = chain->onchain_hrp;
+
+	/* out buffer is 73 + strlen(human readable part),
+	 * see common/bech32.h*/
+	out = tal_arr(ctx, char, 73 + strlen(hrp));
+	pubkey_to_hash160(pubkey, &h160);
+	ok = segwit_addr_encode(out, hrp, 0, h160.u.u8, sizeof(h160));
+        if(!ok)
+                tal_free(out);
+	return out;
+}
+
+int main(int argc, char *argv[])
+{
+	u8 *sig;
+	u8 varint[VARINT_MAX_LEN];
+	size_t varintlen, msg_len;
+	secp256k1_ecdsa_recoverable_signature rsig;
+	struct sha256_ctx sctx = SHA256_INIT;
+	struct sha256_double shad;
+	struct pubkey reckey;
+	const char *addr;
+	const struct chainparams *chain = NULL;
+	const char *input_chain = NULL, *input_address = NULL;
+
+	setup_locale();
+	err_set_progname(argv[0]);
+	wally_init(0);
+	secp256k1_ctx = wally_get_secp_context();
+
+	if (argc != 3 && argc != 4 && argc != 5)
+		usage();
+	if (argc > 3)
+		input_address = argv[3];
+	if (argc > 4)
+		input_chain = argv[4];
+
+	sig = tal_hexdata(NULL, argv[2], strlen(argv[2]));
+	if (!sig)
+		errx(1, "Not a valid hex string");
+
+	if (sig[0] < 39 || sig[0] >= 43)
+		errx(1,
+		     "Signature header does not correspond to a P2WPKH type");
+
+	if (!secp256k1_ecdsa_recoverable_signature_parse_compact(
+		secp256k1_ctx, &rsig, sig + 1, sig[0] - 39))
+		errx(1, "Signature not parsable");
+
+	sha256_update(&sctx,
+		      "\x18"
+		      "Bitcoin Signed Message:\n",
+		      strlen("\x18"
+			     "Bitcoin Signed Message:\n"));
+	msg_len = strlen(argv[1]);
+	varintlen = varint_put(varint, msg_len);
+	sha256_update(&sctx, varint, varintlen);
+	sha256_update(&sctx, argv[1], msg_len);
+	sha256_double_done(&sctx, &shad);
+
+	if (!secp256k1_ecdsa_recover(secp256k1_ctx, &reckey.pubkey, &rsig,
+				     shad.sha.u.u8))
+		errx(1, "Signature not recoverable");
+
+	if (input_chain) {
+		chain = chainparams_for_network(input_chain);
+		if (!chain)
+			errx(1, "Invalid network");
+	} else {
+		/* By default, assume we are verifying a mainnet signature. */
+		chain = chainparams_for_network("bitcoin");
+	}
+	addr = encode_pubkey_to_p2wpkh_addr(NULL, &reckey, chain);
+	if (!addr)
+		errx(1, "Failed to derive address from recovered key");
+	if (input_address) {
+		if (!streq(addr, input_address))
+			errx(1, "Signature is invalid");
+		printf("Signature is valid!\n");
+	} else
+		printf("Signature claims to be from address %s\n", addr);
+	return 0;
+}
+

doc/schemas/signmessagewithkey.json

@@ -0,0 +1,93 @@
+{
+  "$schema": "../rpc-schema-draft.json",
+  "type": "object",
+  "rpc": "signmessagewithkey",
+  "title": "Command to create a signature using a key from the wallet",
+  "description": [
+    "The **signmessagewithkey** RPC command creates a digital signature of *message* using the key associated with the address provided in the input.",
+    "The signature scheme follows the BIP137 specification."
+  ],
+  "added": "v25.05",
+  "request": {
+    "required": [
+      "message",
+      "address"
+    ],
+    "additionalProperties": false,
+    "properties": {
+      "message": {
+        "type": "string",
+        "description": [
+          "Less than 65536 characters long message to be signed by the node."
+        ]
+      },
+      "address": {
+        "type": "string",
+        "description": [
+          "A Bitcoin accepted type address for lookup in the list of addresses issued to date.",
+          "Only P2WPKH type addresses are supported"
+        ]
+      }
+    }
+  },
+  "response": {
+    "required": [
+      "address",
+      "pubkey",
+      "signature",
+      "base64"
+    ],
+    "additionalProperties": false,
+    "properties": {
+      "address": {
+        "type": "string",
+        "description": [
+          "The bitcoin address used for signing."
+        ]
+      },
+      "pubkey": {
+        "type": "pubkey",
+        "description": [
+          "The public key associated with the bitcoin address provided."
+        ]
+      },
+      "signature": {
+        "type": "hex",
+        "description": [
+          "The signature."
+        ]
+      },
+      "base64": {
+        "type": "string",
+        "description": [
+          "The signature encoded in base64."
+        ]
+      }
+    }
+  },
+  "author": [
+    "Lagrang3 <<[email protected]>> is mainly responsible."
+  ],
+  "see_also": [],
+  "resources": [
+    "Main web site: <https://github.com/ElementsProject/lightning>"
+  ],
+  "examples": [
+    {
+      "request": {
+        "id": "example:signmessagewithkey#1",
+        "method": "signmessagewithkey",
+        "params": {
+          "message": "a test message",
+          "address": "bcrt1qgrh5vtf63mtayzhxwp480aww3j3qfr5qpq65un"
+        }
+      },
+      "response": {
+        "address": "bcrt1qgrh5vtf63mtayzhxwp480aww3j3qfr5qpq65un",
+        "pubkey": "03bc4a456585ba21ba26af4a0e5399ec76410b2e0ca67db0f3bcb2f47b232fa4b0",
+        "signature": "28564edf260a72d991cbb38cf608e293124f8b8f478d13d4544fe27b9d76c65df1284ca395ccdfd3d5f151729ef18f56c028f5f860155d6aa4d0aaaa176a00db01",
+        "base64": "KFZO3yYKctmRy7OM9gjikxJPi49HjRPUVE/ie512xl3xKEyjlczf09XxUXKe8Y9WwCj1+GAVXWqk0KqqF2oA2wE="
+      }
+    }
+  ]
+}

hsmd/hsmd.c

@@ -692,6 +692,7 @@ static struct io_plan *handle_client(struct io_conn *conn, struct client *c)
 	case WIRE_HSMD_GET_CHANNEL_BASEPOINTS:
 	case WIRE_HSMD_SIGN_INVOICE:
 	case WIRE_HSMD_SIGN_MESSAGE:
+	case WIRE_HSMD_BIP137_SIGN_MESSAGE:
 	case WIRE_HSMD_SIGN_OPTION_WILL_FUND_OFFER:
 	case WIRE_HSMD_SIGN_BOLT12:
 	case WIRE_HSMD_SIGN_BOLT12_2:
@@ -748,6 +749,7 @@ static struct io_plan *handle_client(struct io_conn *conn, struct client *c)
 	case WIRE_HSMD_GET_CHANNEL_BASEPOINTS_REPLY:
 	case WIRE_HSMD_DEV_MEMLEAK_REPLY:
 	case WIRE_HSMD_SIGN_MESSAGE_REPLY:
+	case WIRE_HSMD_BIP137_SIGN_MESSAGE_REPLY:
 	case WIRE_HSMD_GET_OUTPUT_SCRIPTPUBKEY_REPLY:
 	case WIRE_HSMD_SIGN_BOLT12_REPLY:
 	case WIRE_HSMD_SIGN_BOLT12_2_REPLY:

hsmd/hsmd_wire.csv

@@ -364,6 +364,15 @@ msgdata,hsmd_sign_message,msg,u8,len
 msgtype,hsmd_sign_message_reply,123
 msgdata,hsmd_sign_message_reply,sig,secp256k1_ecdsa_recoverable_signature,
 
+# sign a raw message with a derived key
+msgtype,hsmd_bip137_sign_message,45
+msgdata,hsmd_bip137_sign_message,len,u16,
+msgdata,hsmd_bip137_sign_message,msg,u8,len
+msgdata,hsmd_bip137_sign_message,keyidx,u32,
+
+msgtype,hsmd_bip137_sign_message_reply,145
+msgdata,hsmd_bip137_sign_message_reply,sig,secp256k1_ecdsa_recoverable_signature,
+
 # lightningd needs to get a scriptPubkey for a utxo with closeinfo
 msgtype,hsmd_get_output_scriptpubkey,24
 msgdata,hsmd_get_output_scriptpubkey,channel_id,u64,