common: sphinx_path_new to take explicit len.

Useful if associated_data is not a tal pointer (xpay wants this).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

common/sphinx.c

@@ -58,10 +58,18 @@ struct sphinx_path {
 	struct pubkey *rendezvous_id;
 };
 
-struct sphinx_path *sphinx_path_new(const tal_t *ctx, const u8 *associated_data)
+struct sphinx_path *sphinx_path_new(const tal_t *ctx,
+				    const u8 *associated_data,
+				    size_t associated_data_len)
 {
 	struct sphinx_path *sp = tal(ctx, struct sphinx_path);
-	sp->associated_data = tal_dup_talarr(sp, u8, associated_data);
+	if (associated_data) {
+		sp->associated_data
+			= tal_dup_arr(sp, u8, associated_data, associated_data_len, 0);
+	} else {
+		assert(associated_data_len == 0);
+		sp->associated_data = NULL;
+	}
 	sp->session_key = NULL;
 	sp->rendezvous_id = NULL;
 	sp->hops = tal_arr(sp, struct sphinx_hop, 0);
@@ -70,9 +78,10 @@ struct sphinx_path *sphinx_path_new(const tal_t *ctx, const u8 *associated_data)
 
 struct sphinx_path *sphinx_path_new_with_key(const tal_t *ctx,
 					     const u8 *associated_data,
+					     size_t associated_data_len,
 					     const struct secret *session_key)
 {
-	struct sphinx_path *sp = sphinx_path_new(ctx, associated_data);
+	struct sphinx_path *sp = sphinx_path_new(ctx, associated_data, associated_data_len);
 	sp->session_key = tal_dup(sp, struct secret, session_key);
 	return sp;
 }

common/sphinx.h

@@ -182,7 +182,8 @@ u8 *unwrap_onionreply(const tal_t *ctx,
  * passed to `create_onionpacket` to generate the packet.
  */
 struct sphinx_path *sphinx_path_new(const tal_t *ctx,
-				    const u8 *associated_data);
+				    const u8 *associated_data,
+				    size_t associated_data_len);
 
 /**
  * Create a new empty sphinx_path with a given `session_key`.
@@ -192,6 +193,7 @@ struct sphinx_path *sphinx_path_new(const tal_t *ctx,
  */
 struct sphinx_path *sphinx_path_new_with_key(const tal_t *ctx,
 					     const u8 *associated_data,
+					     size_t associated_data_len,
 					     const struct secret *session_key);
 
 /**

common/test/run-blindedpath_onion.c

@@ -235,7 +235,7 @@ int main(int argc, char *argv[])
 	pubkey_from_privkey(&path_key[DAVE], &path_key_pub[DAVE]);
 
 	/* Create an onion which encodes this. */
-	sphinx_path = sphinx_path_new(tmpctx, NULL);
+	sphinx_path = sphinx_path_new(tmpctx, NULL, 0);
 	for (size_t i = 0; i < 4; i++) {
 		struct tlv_onionmsg_tlv *payload
 			= tlv_onionmsg_tlv_new(tmpctx);

common/test/run-onion-message-test.c

@@ -306,7 +306,7 @@ int main(int argc, char *argv[])
 	json_strfield("unknown_tag_1", "68656c6c6f");
 
 	/* Create the onionmessage */
-	sphinx_path = sphinx_path_new(tmpctx, NULL);
+	sphinx_path = sphinx_path_new(tmpctx, NULL, 0);
 	for (size_t i = 0; i < ARRAY_SIZE(erd); i++) {
 		struct tlv_onionmsg_tlv *tlv = tlv_onionmsg_tlv_new(tmpctx);
 		u8 *onionmsg_tlv;

common/test/run-onion-test-vector.c

@@ -161,7 +161,8 @@ int main(int argc, char *argv[])
 	generate_tok = json_get_member(json, toks, "generate");
 	json_to_secret(json, json_get_member(json, generate_tok, "session_key"), &session_key);
 	assoc_data = json_tok_bin_from_hex(tmpctx, json, json_get_member(json, generate_tok, "associated_data"));
-	sp = sphinx_path_new_with_key(tmpctx, assoc_data, &session_key);
+	sp = sphinx_path_new_with_key(tmpctx, assoc_data, tal_bytelen(assoc_data),
+				      &session_key);
 	json_for_each_arr(i, t, json_get_member(json, generate_tok, "hops")) {
 		struct pubkey k;
 		const u8 *cursor;

common/test/run-route_blinding_onion_test.c

@@ -171,7 +171,8 @@ int main(int argc, char *argv[])
 	}
 
 	/* Now, create onion! */
-	sp = sphinx_path_new_with_key(tmpctx, associated_data, &session_key);
+	sp = sphinx_path_new_with_key(tmpctx, associated_data, tal_bytelen(associated_data),
+				      &session_key);
 	for (i = 0; i < tal_count(ids); i++)
 		sphinx_add_hop_has_length(sp, &ids[i], onionhops[i]);