#include "bitcoin/feerate.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include void json_add_uncommitted_channel(struct json_stream *response, const struct uncommitted_channel *uc) { struct amount_msat total, ours; if (!uc) return; /* If we're chatting but no channel, that's shown by connected: True */ if (!uc->fc) return; json_object_start(response, NULL); json_add_string(response, "state", "OPENINGD"); json_add_string(response, "owner", "lightning_openingd"); json_add_string(response, "funding", "LOCAL"); if (uc->transient_billboard) { json_array_start(response, "status"); json_add_string(response, NULL, uc->transient_billboard); json_array_end(response); } /* These should never fail. */ if (amount_sat_to_msat(&total, uc->fc->funding) && amount_msat_sub(&ours, total, uc->fc->push)) { json_add_amount_msat_compat(response, ours, "msatoshi_to_us", "to_us_msat"); json_add_amount_msat_compat(response, total, "msatoshi_total", "total_msat"); } json_array_start(response, "features"); if (feature_negotiated(uc->peer->ld->our_features, uc->peer->their_features, OPT_STATIC_REMOTEKEY)) json_add_string(response, NULL, "option_static_remotekey"); if (feature_negotiated(uc->peer->ld->our_features, uc->peer->their_features, OPT_ANCHOR_OUTPUTS)) json_add_string(response, NULL, "option_anchor_outputs"); json_array_end(response); json_object_end(response); } /* Steals fields from uncommitted_channel: returns NULL if can't generate a * key for this channel (shouldn't happen!). */ static struct channel * wallet_commit_channel(struct lightningd *ld, struct uncommitted_channel *uc, struct channel_id *cid, struct bitcoin_tx *remote_commit, struct bitcoin_signature *remote_commit_sig, const struct bitcoin_txid *funding_txid, u16 funding_outnum, struct amount_sat funding, struct amount_msat push, u8 channel_flags, struct channel_info *channel_info, u32 feerate, const u8 *our_upfront_shutdown_script, const u8 *remote_upfront_shutdown_script) { struct channel *channel; struct amount_msat our_msat; struct amount_sat local_funding; s64 final_key_idx; u64 static_remotekey_start; bool option_anchor_outputs; /* We cannot both be the fundee *and* have a `fundchannel_start` * command running! */ assert(!(uc->got_offer && uc->fc)); /* Get a key to use for closing outputs from this tx */ final_key_idx = wallet_get_newindex(ld); if (final_key_idx == -1) { log_broken(uc->log, "Can't get final key index"); return NULL; } if (uc->fc) { if (!amount_sat_sub_msat(&our_msat, funding, push)) { log_broken(uc->log, "push %s exceeds funding %s", type_to_string(tmpctx, struct amount_msat, &push), type_to_string(tmpctx, struct amount_sat, &funding)); return NULL; } local_funding = funding; } else { our_msat = push; local_funding = AMOUNT_SAT(0); } /* old_remote_per_commit not valid yet, copy valid one. */ channel_info->old_remote_per_commit = channel_info->remote_per_commit; /* BOLT #2: * 1. type: 35 (`funding_signed`) * 2. data: * * [`channel_id`:`channel_id`] * * [`signature`:`signature`] * * #### Requirements * * Both peers: * - if `option_static_remotekey` or `option_anchor_outputs` was negotiated: * - `option_static_remotekey` or `option_anchor_outputs` applies to all commitment * transactions * - otherwise: * - `option_static_remotekey` or `option_anchor_outputs` does not apply to any commitment * transactions */ /* i.e. We set it now for the channel permanently. */ if (feature_negotiated(ld->our_features, uc->peer->their_features, OPT_STATIC_REMOTEKEY)) static_remotekey_start = 0; else static_remotekey_start = 0x7FFFFFFFFFFFFFFF; option_anchor_outputs = feature_negotiated(ld->our_features, uc->peer->their_features, OPT_ANCHOR_OUTPUTS); channel = new_channel(uc->peer, uc->dbid, NULL, /* No shachain yet */ CHANNELD_AWAITING_LOCKIN, uc->fc ? LOCAL : REMOTE, uc->log, take(uc->transient_billboard), channel_flags, &uc->our_config, uc->minimum_depth, 1, 1, 0, funding_txid, funding_outnum, funding, push, local_funding, false, /* !remote_funding_locked */ NULL, /* no scid yet */ cid, /* The three arguments below are msatoshi_to_us, * msatoshi_to_us_min, and msatoshi_to_us_max. * Because, this is a newly-funded channel, * all three are same value. */ our_msat, our_msat, /* msat_to_us_min */ our_msat, /* msat_to_us_max */ remote_commit, remote_commit_sig, NULL, /* No HTLC sigs yet */ channel_info, take(new_fee_states(NULL, uc->fc ? LOCAL : REMOTE, &feerate)), NULL, /* No shutdown_scriptpubkey[REMOTE] yet */ our_upfront_shutdown_script, final_key_idx, false, NULL, /* No commit sent yet */ /* If we're fundee, could be a little before this * in theory, but it's only used for timing out. */ get_network_blockheight(ld->topology), feerate, feerate, /* We are connected */ true, &uc->local_basepoints, &uc->local_funding_pubkey, NULL, ld->config.fee_base, ld->config.fee_per_satoshi, remote_upfront_shutdown_script, static_remotekey_start, static_remotekey_start, option_anchor_outputs, NUM_SIDES, /* closer not yet known */ uc->fc ? REASON_USER : REASON_REMOTE, NULL); /* Now we finally put it in the database. */ wallet_channel_insert(ld->wallet, channel); return channel; } /** cancel_after_fundchannel_complete_success * * @brief Called to cancel a `fundchannel` after * a `fundchannel_complete` succeeds. * * @desc Specifically, this is called when a * `fundchannel_cancel` is blocked due to a * parallel `fundchannel_complete` still running. * After the `fundchannel_complete` succeeds, we * invoke this function to cancel the funding * after all. * * In effect, this forces the `fundchannel_cancel` * to be invoked after the `fundchannel_complete` * succeeds, leading to a reasonable serial * execution. * * @param cmd - The `fundchannel_cancel` command * that wants to cancel this. * @param channel - The channel being cancelled. */ static void cancel_after_fundchannel_complete_success(struct command *cmd, struct channel *channel) { was_pending(cancel_channel_before_broadcast(cmd, channel->peer)); } static void funding_success(struct channel *channel) { struct json_stream *response; struct funding_channel *fc = channel->peer->uncommitted_channel->fc; struct command *cmd = fc->cmd; /* Well, those cancels now need to trigger! */ for (size_t i = 0; i < tal_count(fc->cancels); i++) cancel_after_fundchannel_complete_success(fc->cancels[i], channel); response = json_stream_success(cmd); json_add_string(response, "channel_id", type_to_string(tmpctx, struct channel_id, &channel->cid)); json_add_bool(response, "commitments_secured", true); was_pending(command_success(cmd, response)); } static void funding_started_success(struct funding_channel *fc) { struct json_stream *response; struct command *cmd = fc->cmd; char *out; response = json_stream_success(cmd); out = encode_scriptpubkey_to_addr(cmd, chainparams, fc->funding_scriptpubkey); if (out) { json_add_string(response, "funding_address", out); json_add_hex_talarr(response, "scriptpubkey", fc->funding_scriptpubkey); if (fc->our_upfront_shutdown_script) json_add_hex_talarr(response, "close_to", fc->our_upfront_shutdown_script); } /* Clear this so cancel doesn't think it's still in progress */ fc->cmd = NULL; was_pending(command_success(cmd, response)); } static void opening_funder_start_replied(struct subd *openingd, const u8 *resp, const int *fds, struct funding_channel *fc) { u8 *funding_scriptPubkey; bool supports_shutdown_script; if (!fromwire_openingd_funder_start_reply(resp, resp, &funding_scriptPubkey, &supports_shutdown_script)) { log_broken(fc->uc->log, "bad OPENING_FUNDER_REPLY %s", tal_hex(resp, resp)); was_pending(command_fail(fc->cmd, LIGHTNINGD, "bad OPENING_FUNDER_REPLY %s", tal_hex(fc->cmd, resp))); goto failed; } /* If we're not using the upfront shutdown script, forget it */ if (!supports_shutdown_script) fc->our_upfront_shutdown_script = tal_free(fc->our_upfront_shutdown_script); /* Save this so we can indentify output for scriptpubkey */ fc->funding_scriptpubkey = tal_steal(fc, funding_scriptPubkey); funding_started_success(fc); /* Mark that we're in-flight */ fc->inflight = true; return; failed: subd_release_channel(openingd, fc->uc); fc->uc->open_daemon = NULL; /* Frees fc too, and tmpctx */ tal_free(fc->uc); } static void opening_funder_finished(struct subd *openingd, const u8 *resp, const int *fds, struct funding_channel *fc) { struct channel_info channel_info; struct channel_id cid; struct bitcoin_txid funding_txid; u16 funding_txout; struct bitcoin_signature remote_commit_sig; struct bitcoin_tx *remote_commit; u32 feerate; struct channel *channel; struct lightningd *ld = openingd->ld; u8 *remote_upfront_shutdown_script; struct per_peer_state *pps; struct penalty_base *pbase; /* This is a new channel_info.their_config so set its ID to 0 */ channel_info.their_config.id = 0; if (!fromwire_openingd_funder_reply(resp, resp, &channel_info.their_config, &remote_commit, &pbase, &remote_commit_sig, &pps, &channel_info.theirbase.revocation, &channel_info.theirbase.payment, &channel_info.theirbase.htlc, &channel_info.theirbase.delayed_payment, &channel_info.remote_per_commit, &fc->uc->minimum_depth, &channel_info.remote_fundingkey, &funding_txid, &funding_txout, &feerate, &fc->uc->our_config.channel_reserve, &remote_upfront_shutdown_script)) { log_broken(fc->uc->log, "bad OPENING_FUNDER_REPLY %s", tal_hex(resp, resp)); was_pending(command_fail(fc->cmd, LIGHTNINGD, "bad OPENING_FUNDER_REPLY %s", tal_hex(fc->cmd, resp))); goto cleanup; } remote_commit->chainparams = chainparams; per_peer_state_set_fds_arr(pps, fds); log_debug(ld->log, "%s", type_to_string(tmpctx, struct pubkey, &channel_info.remote_per_commit)); /* Saved with channel to disk */ derive_channel_id(&cid, &funding_txid, funding_txout); /* old_remote_per_commit not valid yet, copy valid one. */ channel_info.old_remote_per_commit = channel_info.remote_per_commit; /* Steals fields from uc */ channel = wallet_commit_channel(ld, fc->uc, &cid, remote_commit, &remote_commit_sig, &funding_txid, funding_txout, fc->funding, fc->push, fc->channel_flags, &channel_info, feerate, fc->our_upfront_shutdown_script, remote_upfront_shutdown_script); if (!channel) { was_pending(command_fail(fc->cmd, LIGHTNINGD, "Key generation failure")); goto cleanup; } /* Watch for funding confirms */ channel_watch_funding(ld, channel); if (pbase) wallet_penalty_base_add(ld->wallet, channel->dbid, pbase); funding_success(channel); peer_start_channeld(channel, pps, NULL, false); cleanup: subd_release_channel(openingd, fc->uc); fc->uc->open_daemon = NULL; /* Frees fc too, and tmpctx */ tal_free(fc->uc); } static void opening_fundee_finished(struct subd *openingd, const u8 *reply, const int *fds, struct uncommitted_channel *uc) { const u8 *fwd_msg; struct channel_info channel_info; struct bitcoin_signature remote_commit_sig; struct bitcoin_tx *remote_commit; struct channel_id cid; struct lightningd *ld = openingd->ld; struct bitcoin_txid funding_txid; u16 funding_outnum; struct amount_sat funding; struct amount_msat push; u32 feerate; u8 channel_flags; struct channel *channel; u8 *remote_upfront_shutdown_script, *local_upfront_shutdown_script; struct per_peer_state *pps; struct penalty_base *pbase; log_debug(uc->log, "Got opening_fundee_finish_response"); /* This is a new channel_info.their_config, set its ID to 0 */ channel_info.their_config.id = 0; if (!fromwire_openingd_fundee(tmpctx, reply, &channel_info.their_config, &remote_commit, &pbase, &remote_commit_sig, &pps, &channel_info.theirbase.revocation, &channel_info.theirbase.payment, &channel_info.theirbase.htlc, &channel_info.theirbase.delayed_payment, &channel_info.remote_per_commit, &channel_info.remote_fundingkey, &funding_txid, &funding_outnum, &funding, &push, &channel_flags, &feerate, cast_const2(u8 **, &fwd_msg), &uc->our_config.channel_reserve, &local_upfront_shutdown_script, &remote_upfront_shutdown_script)) { log_broken(uc->log, "bad OPENING_FUNDEE_REPLY %s", tal_hex(reply, reply)); uncommitted_channel_disconnect(uc, LOG_BROKEN, "bad OPENING_FUNDEE_REPLY"); goto failed; } remote_commit->chainparams = chainparams; per_peer_state_set_fds_arr(pps, fds); /* openingd should never accept them funding channel in this case. */ if (peer_active_channel(uc->peer)) { uncommitted_channel_disconnect(uc, LOG_BROKEN, "already have active channel"); goto failed; } derive_channel_id(&cid, &funding_txid, funding_outnum); /* old_remote_per_commit not valid yet, copy valid one. */ channel_info.old_remote_per_commit = channel_info.remote_per_commit; /* Consumes uc */ channel = wallet_commit_channel(ld, uc, &cid, remote_commit, &remote_commit_sig, &funding_txid, funding_outnum, funding, push, channel_flags, &channel_info, feerate, local_upfront_shutdown_script, remote_upfront_shutdown_script); if (!channel) { uncommitted_channel_disconnect(uc, LOG_BROKEN, "Commit channel failed"); goto failed; } log_debug(channel->log, "Watching funding tx %s", type_to_string(reply, struct bitcoin_txid, &channel->funding_txid)); channel_watch_funding(ld, channel); /* Tell plugins about the success */ notify_channel_opened(ld, &channel->peer->id, &channel->funding, &channel->funding_txid, &channel->remote_funding_locked); if (pbase) wallet_penalty_base_add(ld->wallet, channel->dbid, pbase); /* On to normal operation! */ peer_start_channeld(channel, pps, fwd_msg, false); subd_release_channel(openingd, uc); uc->open_daemon = NULL; tal_free(uc); return; failed: close(fds[0]); close(fds[1]); close(fds[3]); tal_free(uc); } static void opening_funder_failed_cancel_commands(struct uncommitted_channel *uc, const char *desc) { /* If no funding command(s) pending, do nothing. */ if (!uc->fc) return; /* Tell anyone who was trying to cancel */ for (size_t i = 0; i < tal_count(uc->fc->cancels); i++) { struct json_stream *response; response = json_stream_success(uc->fc->cancels[i]); json_add_string(response, "cancelled", desc); was_pending(command_success(uc->fc->cancels[i], response)); } /* Tell any fundchannel_complete or fundchannel command */ if (uc->fc->cmd) was_pending(command_fail(uc->fc->cmd, LIGHTNINGD, "%s", desc)); /* Clear uc->fc, so we can try again, and so we don't fail twice * if they close. * This code is also used in the case where we turn out to already * be the fundee, in which case we should not have any `fc` at all, * so we definitely should clear this. */ uc->fc = tal_free(uc->fc); } static void opening_funder_failed(struct subd *openingd, const u8 *msg, struct uncommitted_channel *uc) { char *desc; if (!fromwire_openingd_funder_failed(msg, msg, &desc)) { log_broken(uc->log, "bad OPENING_FUNDER_FAILED %s", tal_hex(tmpctx, msg)); was_pending(command_fail(uc->fc->cmd, LIGHTNINGD, "bad OPENING_FUNDER_FAILED %s", tal_hex(uc->fc->cmd, msg))); tal_free(uc); return; } opening_funder_failed_cancel_commands(uc, desc); } struct openchannel_hook_payload { struct subd *openingd; struct uncommitted_channel* uc; struct amount_sat funding_satoshis; struct amount_msat push_msat; struct amount_sat dust_limit_satoshis; struct amount_msat max_htlc_value_in_flight_msat; struct amount_sat channel_reserve_satoshis; struct amount_msat htlc_minimum_msat; u32 feerate_per_kw; u16 to_self_delay; u16 max_accepted_htlcs; u8 channel_flags; u8 *shutdown_scriptpubkey; const u8 *our_upfront_shutdown_script; char *errmsg; }; static void openchannel_hook_serialize(struct openchannel_hook_payload *payload, struct json_stream *stream, struct plugin *plugin) { struct uncommitted_channel *uc = payload->openingd->channel; json_object_start(stream, "openchannel"); json_add_node_id(stream, "id", &uc->peer->id); json_add_amount_sat_only(stream, "funding_satoshis", payload->funding_satoshis); json_add_amount_msat_only(stream, "push_msat", payload->push_msat); json_add_amount_sat_only(stream, "dust_limit_satoshis", payload->dust_limit_satoshis); json_add_amount_msat_only(stream, "max_htlc_value_in_flight_msat", payload->max_htlc_value_in_flight_msat); json_add_amount_sat_only(stream, "channel_reserve_satoshis", payload->channel_reserve_satoshis); json_add_amount_msat_only(stream, "htlc_minimum_msat", payload->htlc_minimum_msat); json_add_num(stream, "feerate_per_kw", payload->feerate_per_kw); json_add_num(stream, "to_self_delay", payload->to_self_delay); json_add_num(stream, "max_accepted_htlcs", payload->max_accepted_htlcs); json_add_num(stream, "channel_flags", payload->channel_flags); if (tal_count(payload->shutdown_scriptpubkey) != 0) json_add_hex_talarr(stream, "shutdown_scriptpubkey", payload->shutdown_scriptpubkey); json_object_end(stream); /* .openchannel */ } /* openingd dies? Remove openingd ptr from payload */ static void openchannel_payload_remove_openingd(struct subd *openingd, struct openchannel_hook_payload *payload) { assert(payload->openingd == openingd); payload->openingd = NULL; } static void openchannel_hook_final(struct openchannel_hook_payload *payload STEALS) { struct subd *openingd = payload->openingd; const u8 *our_upfront_shutdown_script = payload->our_upfront_shutdown_script; const char *errmsg = payload->errmsg; struct uncommitted_channel* uc = payload->uc; /* We want to free this, whatever happens. */ tal_steal(tmpctx, payload); /* If openingd went away, don't send it anything! */ if (!openingd) return; tal_del_destructor2(openingd, openchannel_payload_remove_openingd, payload); if (!errmsg) { /* Plugins accepted the offer, cancel any of our * funder-side commands. */ opening_funder_failed_cancel_commands(uc, "Have in-progress " "`open_channel` from " "peer"); uc->got_offer = true; } subd_send_msg(openingd, take(towire_openingd_got_offer_reply(NULL, errmsg, our_upfront_shutdown_script))); } static bool openchannel_hook_deserialize(struct openchannel_hook_payload *payload, const char *buffer, const jsmntok_t *toks) { struct subd *openingd = payload->openingd; /* already rejected by prior plugin hook in the chain */ if (payload->errmsg != NULL) return true; if (!toks || !buffer) return true; const jsmntok_t *t_result = json_get_member(buffer, toks, "result"); const jsmntok_t *t_errmsg = json_get_member(buffer, toks, "error_message"); const jsmntok_t *t_closeto = json_get_member(buffer, toks, "close_to"); if (!t_result) fatal("Plugin returned an invalid response to the" " openchannel hook: %.*s", toks[0].end - toks[0].start, buffer + toks[0].start); /* reject */ if (json_tok_streq(buffer, t_result, "reject")) { payload->errmsg = ""; if (t_errmsg) payload->errmsg = json_strdup(payload, buffer, t_errmsg); log_debug(openingd->ld->log, "openchannel hook rejects and says '%s'", payload->errmsg); if (t_closeto) fatal("Plugin rejected openchannel but also set close_to"); openchannel_hook_final(payload); return false; } else if (!json_tok_streq(buffer, t_result, "continue")) { fatal("Plugin returned an invalid result for the " "openchannel hook: %.*s", t_result->end - t_result->start, buffer + t_result->start); } /* Check for a valid 'close_to' address passed back */ if (t_closeto) { /* First plugin can set close_to. Log others. */ if (payload->our_upfront_shutdown_script != NULL) { log_broken(openingd->ld->log, "openchannel hook close_to address was" " already set by other plugin. Ignoring!"); return true; } switch (json_to_address_scriptpubkey(tmpctx, chainparams, buffer, t_closeto, &payload->our_upfront_shutdown_script)) { case ADDRESS_PARSE_UNRECOGNIZED: fatal("Plugin returned an invalid response to" " the openchannel.close_to hook: %.*s", t_closeto->end - t_closeto->start, buffer + t_closeto->start); case ADDRESS_PARSE_WRONG_NETWORK: fatal("Plugin returned invalid response to the" " openchannel.close_to hook: address %s is" " not on network %s", tal_hex(NULL, payload->our_upfront_shutdown_script), chainparams->network_name); case ADDRESS_PARSE_SUCCESS: break; } } return true; } REGISTER_PLUGIN_HOOK(openchannel, openchannel_hook_deserialize, openchannel_hook_final, openchannel_hook_serialize, struct openchannel_hook_payload *); static void opening_got_offer(struct subd *openingd, const u8 *msg, struct uncommitted_channel *uc) { struct openchannel_hook_payload *payload; /* Tell them they can't open, if we already have open channel. */ if (peer_active_channel(uc->peer)) { subd_send_msg(openingd, take(towire_openingd_got_offer_reply(NULL, "Already have active channel", NULL))); return; } payload = tal(openingd, struct openchannel_hook_payload); payload->openingd = openingd; payload->uc = uc; payload->our_upfront_shutdown_script = NULL; payload->errmsg = NULL; if (!fromwire_openingd_got_offer(payload, msg, &payload->funding_satoshis, &payload->push_msat, &payload->dust_limit_satoshis, &payload->max_htlc_value_in_flight_msat, &payload->channel_reserve_satoshis, &payload->htlc_minimum_msat, &payload->feerate_per_kw, &payload->to_self_delay, &payload->max_accepted_htlcs, &payload->channel_flags, &payload->shutdown_scriptpubkey)) { log_broken(openingd->log, "Malformed opening_got_offer %s", tal_hex(tmpctx, msg)); tal_free(openingd); return; } tal_add_destructor2(openingd, openchannel_payload_remove_openingd, payload); plugin_hook_call_openchannel(openingd->ld, payload); } static unsigned int openingd_msg(struct subd *openingd, const u8 *msg, const int *fds) { enum openingd_wire t = fromwire_peektype(msg); struct uncommitted_channel *uc = openingd->channel; switch (t) { case WIRE_OPENINGD_FUNDER_REPLY: if (!uc->fc) { log_broken(openingd->log, "Unexpected FUNDER_REPLY %s", tal_hex(tmpctx, msg)); tal_free(openingd); return 0; } if (tal_count(fds) != 3) return 3; opening_funder_finished(openingd, msg, fds, uc->fc); return 0; case WIRE_OPENINGD_FUNDER_START_REPLY: if (!uc->fc) { log_broken(openingd->log, "Unexpected FUNDER_START_REPLY %s", tal_hex(tmpctx, msg)); tal_free(openingd); return 0; } opening_funder_start_replied(openingd, msg, fds, uc->fc); return 0; case WIRE_OPENINGD_FUNDER_FAILED: if (!uc->fc) { log_unusual(openingd->log, "Unexpected FUNDER_FAILED %s", tal_hex(tmpctx, msg)); tal_free(openingd); return 0; } opening_funder_failed(openingd, msg, uc); return 0; case WIRE_OPENINGD_FUNDEE: if (tal_count(fds) != 3) return 3; opening_fundee_finished(openingd, msg, fds, uc); return 0; case WIRE_OPENINGD_GOT_OFFER: opening_got_offer(openingd, msg, uc); return 0; /* We send these! */ case WIRE_OPENINGD_INIT: case WIRE_OPENINGD_FUNDER_START: case WIRE_OPENINGD_FUNDER_COMPLETE: case WIRE_OPENINGD_FUNDER_CANCEL: case WIRE_OPENINGD_GOT_OFFER_REPLY: case WIRE_OPENINGD_DEV_MEMLEAK: /* Replies never get here */ case WIRE_OPENINGD_DEV_MEMLEAK_REPLY: break; } switch ((enum common_wire)t) { #if DEVELOPER case WIRE_CUSTOMMSG_IN: handle_custommsg_in(openingd->ld, openingd->node_id, msg); return 0; #else case WIRE_CUSTOMMSG_IN: #endif /* We send these. */ case WIRE_CUSTOMMSG_OUT: break; } log_broken(openingd->log, "Unexpected msg %s: %s", openingd_wire_name(t), tal_hex(tmpctx, msg)); tal_free(openingd); return 0; } void peer_start_openingd(struct peer *peer, struct per_peer_state *pps) { int hsmfd; u32 max_to_self_delay; struct amount_msat min_effective_htlc_capacity; struct uncommitted_channel *uc; const u8 *msg; assert(!peer->uncommitted_channel); uc = peer->uncommitted_channel = new_uncommitted_channel(peer); hsmfd = hsm_get_client_fd(peer->ld, &uc->peer->id, uc->dbid, HSM_CAP_COMMITMENT_POINT | HSM_CAP_SIGN_REMOTE_TX); uc->open_daemon = new_channel_subd(peer->ld, "lightning_openingd", uc, &peer->id, uc->log, true, openingd_wire_name, openingd_msg, opend_channel_errmsg, opend_channel_set_billboard, take(&pps->peer_fd), take(&pps->gossip_fd), take(&pps->gossip_store_fd), take(&hsmfd), NULL); if (!uc->open_daemon) { uncommitted_channel_disconnect(uc, LOG_BROKEN, tal_fmt(tmpctx, "Running lightning_openingd: %s", strerror(errno))); tal_free(uc); return; } channel_config(peer->ld, &uc->our_config, &max_to_self_delay, &min_effective_htlc_capacity); /* BOLT #2: * * The sender: * - SHOULD set `minimum_depth` to a number of blocks it considers * reasonable to avoid double-spending of the funding transaction. */ uc->minimum_depth = peer->ld->config.anchor_confirms; msg = towire_openingd_init(NULL, chainparams, peer->ld->our_features, &uc->our_config, max_to_self_delay, min_effective_htlc_capacity, pps, &uc->local_basepoints, &uc->local_funding_pubkey, uc->minimum_depth, feerate_min(peer->ld, NULL), feerate_max(peer->ld, NULL), peer->their_features, feature_negotiated(peer->ld->our_features, peer->their_features, OPT_STATIC_REMOTEKEY), feature_negotiated(peer->ld->our_features, peer->their_features, OPT_ANCHOR_OUTPUTS), IFDEV(peer->ld->dev_force_tmp_channel_id, NULL), IFDEV(peer->ld->dev_fast_gossip, false)); subd_send_msg(uc->open_daemon, take(msg)); } static struct command_result *json_fundchannel_complete(struct command *cmd, const char *buffer, const jsmntok_t *obj UNNEEDED, const jsmntok_t *params) { u8 *msg; struct node_id *id; struct bitcoin_txid *funding_txid; struct peer *peer; struct channel *channel; struct wally_psbt *funding_psbt; u32 *funding_txout_num = NULL; struct funding_channel *fc; bool old_api; /* params is NULL for initial parameter desc generation! */ if (params && deprecated_apis) { /* We used to have a three-arg version. */ if (params->type == JSMN_ARRAY) old_api = (params->size == 3); else old_api = (json_get_member(buffer, params, "txid") != NULL); if (old_api) { if (!param(cmd, buffer, params, p_req("id", param_node_id, &id), p_req("txid", param_txid, &funding_txid), p_req("txout", param_number, &funding_txout_num), NULL)) return command_param_failed(); } } else old_api = false; if (!old_api) { if (!param(cmd, buffer, params, p_req("id", param_node_id, &id), p_req("psbt", param_psbt, &funding_psbt), NULL)) return command_param_failed(); } peer = peer_by_id(cmd->ld, id); if (!peer) { return command_fail(cmd, FUNDING_UNKNOWN_PEER, "Unknown peer"); } channel = peer_active_channel(peer); if (channel) return command_fail(cmd, LIGHTNINGD, "Peer already %s", channel_state_name(channel)); if (!peer->uncommitted_channel) return command_fail(cmd, FUNDING_PEER_NOT_CONNECTED, "Peer not connected"); if (!peer->uncommitted_channel->fc || !peer->uncommitted_channel->fc->inflight) return command_fail(cmd, LIGHTNINGD, "No channel funding in progress."); if (peer->uncommitted_channel->fc->cmd) return command_fail(cmd, LIGHTNINGD, "Channel funding in progress."); fc = peer->uncommitted_channel->fc; if (!old_api) { /* Figure out the correct output, and perform sanity checks. */ for (size_t i = 0; i < funding_psbt->tx->num_outputs; i++) { if (memeq(funding_psbt->tx->outputs[i].script, funding_psbt->tx->outputs[i].script_len, fc->funding_scriptpubkey, tal_bytelen(fc->funding_scriptpubkey))) { if (funding_txout_num) return command_fail(cmd, FUNDING_PSBT_INVALID, "Two outputs to open channel"); funding_txout_num = tal(cmd, u32); *funding_txout_num = i; } } if (!funding_txout_num) return command_fail(cmd, FUNDING_PSBT_INVALID, "No output to open channel"); /* Can't really check amounts for elements. */ if (!chainparams->is_elements && !amount_sat_eq(amount_sat(funding_psbt->tx->outputs [*funding_txout_num].satoshi), fc->funding)) return command_fail(cmd, FUNDING_PSBT_INVALID, "Output to open channel is %"PRIu64"sat," " should be %s", funding_psbt->tx->outputs [*funding_txout_num].satoshi, type_to_string(tmpctx, struct amount_sat, &fc->funding)); funding_txid = tal(cmd, struct bitcoin_txid); psbt_txid(NULL, funding_psbt, funding_txid, NULL); } /* Fun fact: our wire protocol only allows 16 bits for outnum. * That is reflected in our encoding scheme for short_channel_id. */ if (*funding_txout_num > UINT16_MAX) return command_fail(cmd, JSONRPC2_INVALID_PARAMS, "Invalid parameter: funding tx vout too large %u", *funding_txout_num); /* Set the cmd to this new cmd */ peer->uncommitted_channel->fc->cmd = cmd; msg = towire_openingd_funder_complete(NULL, funding_txid, *funding_txout_num); subd_send_msg(peer->uncommitted_channel->open_daemon, take(msg)); return command_still_pending(cmd); } /** * json_fundchannel_cancel - Entrypoint for cancelling a channel which funding isn't broadcast */ static struct command_result *json_fundchannel_cancel(struct command *cmd, const char *buffer, const jsmntok_t *obj UNNEEDED, const jsmntok_t *params) { struct node_id *id; struct peer *peer; u8 *msg; if (!param(cmd, buffer, params, p_req("id", param_node_id, &id), NULL)) return command_param_failed(); peer = peer_by_id(cmd->ld, id); if (!peer) { return command_fail(cmd, FUNDING_UNKNOWN_PEER, "Unknown peer"); } if (peer->uncommitted_channel) { if (!peer->uncommitted_channel->fc || !peer->uncommitted_channel->fc->inflight) return command_fail(cmd, FUNDING_NOTHING_TO_CANCEL, "No channel funding in progress."); /* Make sure this gets notified if we succeed or cancel */ tal_arr_expand(&peer->uncommitted_channel->fc->cancels, cmd); msg = towire_openingd_funder_cancel(NULL); subd_send_msg(peer->uncommitted_channel->open_daemon, take(msg)); return command_still_pending(cmd); } /* Handle `fundchannel_cancel` after `fundchannel_complete`. */ return cancel_channel_before_broadcast(cmd, peer); } /** * json_fundchannel_start - Entrypoint for funding a channel */ static struct command_result *json_fundchannel_start(struct command *cmd, const char *buffer, const jsmntok_t *obj UNNEEDED, const jsmntok_t *params) { struct funding_channel * fc = tal(cmd, struct funding_channel); struct node_id *id; struct peer *peer; struct channel *channel; bool *announce_channel; u32 *feerate_per_kw; u8 *msg = NULL; struct amount_sat *amount; struct amount_msat *push_msat; fc->cmd = cmd; fc->cancels = tal_arr(fc, struct command *, 0); fc->uc = NULL; fc->inflight = false; fc->funding_scriptpubkey = NULL; if (!param(fc->cmd, buffer, params, p_req("id", param_node_id, &id), p_req("amount", param_sat, &amount), p_opt("feerate", param_feerate, &feerate_per_kw), p_opt_def("announce", param_bool, &announce_channel, true), p_opt("close_to", param_bitcoin_address, &fc->our_upfront_shutdown_script), p_opt("push_msat", param_msat, &push_msat), NULL)) return command_param_failed(); if (push_msat && amount_msat_greater_sat(*push_msat, *amount)) return command_fail(cmd, FUND_CANNOT_AFFORD, "Requested to push_msat of %s is greater than " "available funding amount %s", type_to_string(tmpctx, struct amount_msat, push_msat), type_to_string(tmpctx, struct amount_sat, amount)); fc->funding = *amount; if (!feerate_per_kw) { feerate_per_kw = tal(cmd, u32); *feerate_per_kw = opening_feerate(cmd->ld->topology); if (!*feerate_per_kw) { return command_fail(cmd, LIGHTNINGD, "Cannot estimate fees"); } } if (*feerate_per_kw < feerate_floor()) { return command_fail(cmd, LIGHTNINGD, "Feerate below feerate floor"); } if (!topology_synced(cmd->ld->topology)) { return command_fail(cmd, FUNDING_STILL_SYNCING_BITCOIN, "Still syncing with bitcoin network"); } peer = peer_by_id(cmd->ld, id); if (!peer) { return command_fail(cmd, FUNDING_UNKNOWN_PEER, "Unknown peer"); } channel = peer_active_channel(peer); if (channel) { return command_fail(cmd, LIGHTNINGD, "Peer already %s", channel_state_name(channel)); } if (!peer->uncommitted_channel) { if (feature_negotiated(cmd->ld->our_features, peer->their_features, OPT_DUAL_FUND)) return command_fail(cmd, FUNDING_STATE_INVALID, "Peer negotiated" " `option_dual_fund`," " must use `openchannel_init` not" " `fundchannel_start`."); return command_fail(cmd, FUNDING_PEER_NOT_CONNECTED, "Peer not connected"); } if (peer->uncommitted_channel->fc) { return command_fail(cmd, LIGHTNINGD, "Already funding channel"); } if (peer->uncommitted_channel->got_offer) { return command_fail(cmd, LIGHTNINGD, "Have in-progress " "`open_channel` from " "peer"); } /* BOLT #2: * - if both nodes advertised `option_support_large_channel`: * - MAY set `funding_satoshis` greater than or equal to 2^24 satoshi. * - otherwise: * - MUST set `funding_satoshis` to less than 2^24 satoshi. */ if (!feature_negotiated(cmd->ld->our_features, peer->their_features, OPT_LARGE_CHANNELS) && amount_sat_greater(*amount, chainparams->max_funding)) return command_fail(cmd, FUND_MAX_EXCEEDED, "Amount exceeded %s", type_to_string(tmpctx, struct amount_sat, &chainparams->max_funding)); fc->push = push_msat ? *push_msat : AMOUNT_MSAT(0); fc->channel_flags = OUR_CHANNEL_FLAGS; if (!*announce_channel) { fc->channel_flags &= ~CHANNEL_FLAGS_ANNOUNCE_CHANNEL; log_info(peer->ld->log, "Will open private channel with node %s", type_to_string(fc, struct node_id, id)); } peer->uncommitted_channel->fc = tal_steal(peer->uncommitted_channel, fc); fc->uc = peer->uncommitted_channel; /* Needs to be stolen away from cmd */ if (fc->our_upfront_shutdown_script) fc->our_upfront_shutdown_script = tal_steal(fc, fc->our_upfront_shutdown_script); msg = towire_openingd_funder_start(NULL, *amount, fc->push, fc->our_upfront_shutdown_script, *feerate_per_kw, fc->channel_flags); subd_send_msg(peer->uncommitted_channel->open_daemon, take(msg)); return command_still_pending(cmd); } static const struct json_command fundchannel_start_command = { "fundchannel_start", "channels", json_fundchannel_start, "Start fund channel with {id} using {amount} satoshis. " "Returns a bech32 address to use as an output for a funding transaction." }; AUTODATA(json_command, &fundchannel_start_command); static const struct json_command fundchannel_cancel_command = { "fundchannel_cancel", "channels", json_fundchannel_cancel, "Cancel inflight channel establishment with peer {id}." }; AUTODATA(json_command, &fundchannel_cancel_command); static const struct json_command fundchannel_complete_command = { "fundchannel_complete", "channels", json_fundchannel_complete, "Complete channel establishment with peer {id} for funding transaction" "with {psbt}. Returns true on success, false otherwise." }; AUTODATA(json_command, &fundchannel_complete_command); struct subd *peer_get_owning_subd(struct peer *peer) { struct channel *channel; channel = peer_active_channel(peer); if (channel != NULL) { return channel->owner; } else if (peer->uncommitted_channel != NULL) { return peer->uncommitted_channel->open_daemon; } return NULL; }