lnsocket

commit c161f4d25ea5e484bc06b7f2381da7203e7945c3
parent 3ce5ac8682fc4bb84bf59317dab05ebb4efd1d41
Author: William Casarin <jb55@jb55.com>
Date:   Sun, 16 Jan 2022 12:55:39 -0800

write message

Diffstat:
M
crypto.c
 | 
6
+++++-
M
crypto.h
 | 
2
++
M
lnsocket.c
 | 
26
++++++++++++++++++++++++++
M
lnsocket.h
 | 
1
+
M
test.c
 | 
9
+++++++++

5 files changed, 43 insertions(+), 1 deletion(-)
diff --git a/crypto.c b/crypto.c
@@ -150,8 +150,12 @@ u8 *cryptomsg_encrypt_msg(struct crypto_state *cs, const u8 *msg, unsigned long 
 	be16 l;
 	int ret;
 
-	if (outcap < sizeof(l) + 16 + mlen + 16)
+	*outlen = sizeof(l) + 16 + mlen + 16; 
+
+	if (outcap < *outlen) {
+		*outlen = 0;
 		return NULL;
+	}
 
 	/* BOLT #8:
 	 *
diff --git a/crypto.h b/crypto.h
@@ -43,4 +43,6 @@ void hkdf_two_keys(struct secret *out1, struct secret *out2,
 			  const struct secret *in1,
 			  const struct secret *in2);
 
+unsigned char *cryptomsg_encrypt_msg(struct crypto_state *cs, const u8 *msg, unsigned long long mlen, u8 *out, size_t *outlen, size_t outcap);
+
 #endif /* LNSOCKET_CRYPTO_H */
diff --git a/lnsocket.c b/lnsocket.c
@@ -74,6 +74,32 @@ static int pubkey_from_node_id(secp256k1_context *secp, struct pubkey *key,
 					 sizeof(id->k));
 }
 
+int lnsocket_write(struct lnsocket *ln, const u8 *msg, int msglen)
+{
+	// this is just temporary so we don't need to move the memory cursor
+	u8 *out = ln->mem.p;
+	ssize_t outcap = ln->mem.end - ln->mem.p;
+	ssize_t writelen;
+	size_t outlen;
+
+	if (!ln->socket)
+		return note_error(&ln->errs, "not connected");
+
+	if (outcap <= 0)
+		return note_error(&ln->errs, "out of memory");
+
+	if (!cryptomsg_encrypt_msg(&ln->crypto_state, msg, msglen, out, &outlen, (size_t)outcap))
+		return note_error(&ln->errs, "encrypt message failed, out of memory");
+
+	if ((writelen = write(ln->socket, out, outlen)) != outlen)
+		return note_error(&ln->errs,
+				"write failed. wrote %ld bytes, expected %ld %s",
+				writelen, outlen,
+				writelen < 0 ? strerror(errno) : "");
+
+	return 1;
+}
+
 struct lnsocket *lnsocket_create_with(int memory)
 {
 	struct cursor mem;
diff --git a/lnsocket.h b/lnsocket.h
@@ -4,6 +4,7 @@
 struct lnsocket;
 
 int lnsocket_connect(struct lnsocket *, const char *node_id, const char *host);
+int lnsocket_write(struct lnsocket *, const unsigned char *msg, int msg_len);
 void lnsocket_genkey(struct lnsocket *);
 struct lnsocket *lnsocket_create();
 void lnsocket_destroy(struct lnsocket *);
diff --git a/test.c b/test.c
@@ -16,6 +16,15 @@ int main(int argc, const char *argv[])
 	}
 
 	printf("connected!\n");
+
+	const unsigned char msg[] = {'h', 'i'};
+
+	if (!lnsocket_write(ln, msg, sizeof(msg))) {
+		lnsocket_print_errors(ln);
+		goto done;
+	}
+
+	printf("wrote message.\n");
 done:
 	lnsocket_destroy(ln);
 	return !ok;