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#include "bitcoin/feerate.h"
#include <bitcoin/privkey.h>
#include <bitcoin/script.h>
#include <ccan/tal/str/str.h>
#include <common/addr.h>
#include <common/channel_config.h>
#include <common/funding_tx.h>
#include <common/json_command.h>
#include <common/jsonrpc_errors.h>
#include <common/key_derive.h>
#include <common/param.h>
#include <common/per_peer_state.h>
#include <common/wallet_tx.h>
#include <common/wire_error.h>
#include <connectd/gen_connect_wire.h>
#include <errno.h>
#include <hsmd/gen_hsm_wire.h>
#include <lightningd/chaintopology.h>
#include <lightningd/channel_control.h>
#include <lightningd/closing_control.h>
#include <lightningd/hsm_control.h>
#include <lightningd/json.h>
#include <lightningd/jsonrpc.h>
#include <lightningd/lightningd.h>
#include <lightningd/log.h>
#include <lightningd/notification.h>
#include <lightningd/opening_control.h>
#include <lightningd/peer_control.h>
#include <lightningd/plugin_hook.h>
#include <lightningd/subd.h>
#include <openingd/gen_opening_wire.h>
#include <wire/wire.h>
#include <wire/wire_sync.h>
/* Channel we're still opening. */
struct uncommitted_channel {
/* peer->uncommitted_channel == this */
struct peer *peer;
/* openingd which is running now */
struct subd *openingd;
/* Reserved dbid for if we become a real struct channel */
u64 dbid;
/* For logging */
struct log *log;
/* Openingd can tell us stuff. */
const char *transient_billboard;
/* If we offered channel, this contains information, otherwise NULL */
struct funding_channel *fc;
/* Our basepoints for the channel. */
struct basepoints local_basepoints;
/* Public key for funding tx. */
struct pubkey local_funding_pubkey;
/* These are *not* filled in by new_uncommitted_channel: */
/* Minimum funding depth (if funder == REMOTE). */
u32 minimum_depth;
/* Our channel config. */
struct channel_config our_config;
};
struct funding_channel {
struct command *cmd; /* Which initially owns us until openingd request */
struct wallet_tx *wtx;
struct amount_msat push;
struct amount_sat funding;
u8 channel_flags;
/* Variables we need to compose fields in cmd's response */
const char *hextx;
struct channel_id cid;
/* Peer we're trying to reach. */
struct pubkey peerid;
/* Channel, subsequent owner of us */
struct uncommitted_channel *uc;
/* Whether or not this is in the middle of getting funded */
bool inflight;
/* Any commands trying to cancel us. */
struct command **cancels;
};
static void uncommitted_channel_disconnect(struct uncommitted_channel *uc,
const char *desc)
{
u8 *msg = towire_connectctl_peer_disconnected(tmpctx, &uc->peer->id);
log_info(uc->log, "%s", desc);
subd_send_msg(uc->peer->ld->connectd, msg);
if (uc->fc)
was_pending(command_fail(uc->fc->cmd, LIGHTNINGD, "%s", desc));
notify_disconnect(uc->peer->ld, &uc->peer->id);
}
void kill_uncommitted_channel(struct uncommitted_channel *uc,
const char *why)
{
log_info(uc->log, "Killing openingd: %s", why);
/* Close openingd. */
subd_release_channel(uc->openingd, uc);
uc->openingd = NULL;
uncommitted_channel_disconnect(uc, why);
tal_free(uc);
}
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_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 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 *remote_upfront_shutdown_script)
{
struct channel *channel;
struct amount_msat our_msat;
s64 final_key_idx;
/* 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;
}
} else
our_msat = push;
/* Feerates begin identical. */
channel_info->feerate_per_kw[LOCAL]
= channel_info->feerate_per_kw[REMOTE]
= feerate;
/* old_remote_per_commit not valid yet, copy valid one. */
channel_info->old_remote_per_commit = channel_info->remote_per_commit;
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,
false, /* !remote_funding_locked */
NULL, /* no scid yet */
/* 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,
NULL, /* No remote_shutdown_scriptpubkey yet */
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_block_height(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);
/* Now we finally put it in the database. */
wallet_channel_insert(ld->wallet, channel);
return channel;
}
static void funding_broadcast_failed(struct channel *channel,
int exitstatus, const char *msg)
{
struct funding_channel *fc = channel->peer->uncommitted_channel->fc;
struct command *cmd = fc->cmd;
/* Massage output into shape so it doesn't kill the JSON serialization */
char *output = tal_strjoin(cmd, tal_strsplit(cmd, msg, "\n", STR_NO_EMPTY), " ", STR_NO_TRAIL);
was_pending(command_fail(cmd, FUNDING_BROADCAST_FAIL,
"Error broadcasting funding transaction: %s", output));
/* Frees fc too */
tal_free(fc->uc);
/* Keep in state CHANNELD_AWAITING_LOCKIN until (manual) broadcast */
}
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 didn't work! */
for (size_t i = 0; i < tal_count(fc->cancels); i++)
was_pending(command_fail(fc->cancels[i], LIGHTNINGD,
"Funding succeeded before cancel"));
response = json_stream_success(cmd);
json_add_string(response, "channel_id",
type_to_string(tmpctx, struct channel_id, &fc->cid));
json_add_bool(response, "commitments_secured", true);
was_pending(command_success(cmd, response));
}
static void funding_broadcast_success(struct channel *channel)
{
struct json_stream *response;
struct funding_channel *fc = channel->peer->uncommitted_channel->fc;
struct command *cmd = fc->cmd;
response = json_stream_success(cmd);
json_add_string(response, "tx", fc->hextx);
json_add_txid(response, "txid", &channel->funding_txid);
json_add_string(response, "channel_id",
type_to_string(tmpctx, struct channel_id, &fc->cid));
was_pending(command_success(cmd, response));
/* Frees fc too */
tal_free(fc->uc);
}
static void funding_broadcast_failed_or_success(struct channel *channel,
int exitstatus, const char *msg)
{
if (exitstatus == 0) {
funding_broadcast_success(channel);
} else {
funding_broadcast_failed(channel, exitstatus, msg);
}
}
static void funding_started_success(struct funding_channel *fc,
u8 *scriptPubkey)
{
struct json_stream *response;
struct command *cmd = fc->cmd;
char *out;
response = json_stream_success(cmd);
out = encode_scriptpubkey_to_addr(cmd,
get_chainparams(cmd->ld)->bip173_name,
scriptPubkey);
if (out)
json_add_string(response, "funding_address", out);
/* 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;
if (!fromwire_opening_funder_start_reply(resp, resp,
&funding_scriptPubkey)) {
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;
}
funding_started_success(fc, funding_scriptPubkey);
/* Mark that we're in-flight */
fc->inflight = true;
return;
failed:
subd_release_channel(openingd, fc->uc);
fc->uc->openingd = NULL;
/* Frees fc too, and tmpctx */
tal_free(fc->uc);
}
static bool compose_and_broadcast_tx(struct lightningd *ld,
const u8 *resp,
struct funding_channel *fc,
struct channel_info *channel_info,
struct channel *channel,
struct bitcoin_txid *expected_txid,
u32 feerate)
{
u8 *msg;
struct pubkey changekey;
u16 funding_outnum;
struct bitcoin_tx *fundingtx;
struct amount_sat change;
struct bitcoin_txid funding_txid;
const struct chainparams *chainparams = get_chainparams(ld);
/* Generate the funding tx. */
if (!amount_sat_eq(fc->wtx->change, AMOUNT_SAT(0))
&& !bip32_pubkey(ld->wallet->bip32_base,
&changekey, fc->wtx->change_key_index))
fatal("Error deriving change key %u", fc->wtx->change_key_index);
fundingtx = funding_tx(tmpctx, chainparams, &funding_outnum,
fc->wtx->utxos, fc->wtx->amount,
&fc->uc->local_funding_pubkey,
&channel_info->remote_fundingkey,
fc->wtx->change, &changekey,
ld->wallet->bip32_base);
log_debug(fc->uc->log, "Funding tx has %zi inputs, %zu outputs:",
fundingtx->wtx->num_inputs,
fundingtx->wtx->num_outputs);
for (size_t i = 0; i < fundingtx->wtx->num_inputs; i++) {
struct bitcoin_txid tmptxid;
bitcoin_tx_input_get_txid(fundingtx, i, &tmptxid);
log_debug(fc->uc->log, "%zi: %s (%s) %s\n",
i,
type_to_string(tmpctx, struct amount_sat,
&fc->wtx->utxos[i]->amount),
fc->wtx->utxos[i]->is_p2sh ? "P2SH" : "SEGWIT",
type_to_string(tmpctx, struct bitcoin_txid,
&tmptxid));
}
bitcoin_txid(fundingtx, &funding_txid);
if (!bitcoin_txid_eq(&funding_txid, expected_txid)) {
log_broken(fc->uc->log,
"Funding txid mismatch:"
" amount %s change %s"
" changeidx %u"
" localkey %s remotekey %s",
type_to_string(tmpctx, struct amount_sat,
&fc->wtx->amount),
type_to_string(tmpctx, struct amount_sat,
&fc->wtx->change),
fc->wtx->change_key_index,
type_to_string(fc, struct pubkey,
&fc->uc->local_funding_pubkey),
type_to_string(fc, struct pubkey,
&channel_info->remote_fundingkey));
was_pending(command_fail(fc->cmd, JSONRPC2_INVALID_PARAMS,
"Funding txid mismatch:"
" amount %s change %s"
" changeidx %u"
" localkey %s remotekey %s",
type_to_string(tmpctx,
struct amount_sat,
&fc->wtx->amount),
type_to_string(tmpctx,
struct amount_sat,
&fc->wtx->change),
fc->wtx->change_key_index,
type_to_string(fc, struct pubkey,
&fc->uc->local_funding_pubkey),
type_to_string(fc, struct pubkey,
&channel_info->remote_fundingkey)));
return false;
}
/* Get HSM to sign the funding tx. */
log_debug(channel->log, "Getting HSM to sign funding tx");
msg = towire_hsm_sign_funding(tmpctx, channel->funding,
fc->wtx->change,
fc->wtx->change_key_index,
&fc->uc->local_funding_pubkey,
&channel_info->remote_fundingkey,
fc->wtx->utxos);
if (!wire_sync_write(ld->hsm_fd, take(msg)))
fatal("Could not write to HSM: %s", strerror(errno));
msg = wire_sync_read(fc, ld->hsm_fd);
if (!fromwire_hsm_sign_funding_reply(tmpctx, msg, &fundingtx))
fatal("HSM gave bad sign_funding_reply %s",
tal_hex(msg, resp));
fundingtx->chainparams = chainparams;
/* Extract the change output and add it to the DB */
wallet_extract_owned_outputs(ld->wallet, fundingtx, NULL, &change);
/* Make sure we recognize our change output by its scriptpubkey in
* future. This assumes that we have only two outputs, may not be true
* if we add support for multifundchannel */
if (fundingtx->wtx->num_outputs == 2)
txfilter_add_scriptpubkey(ld->owned_txfilter, bitcoin_tx_output_get_script(tmpctx, fundingtx, !funding_outnum));
/* Send it out and watch for confirms. */
broadcast_tx(ld->topology, channel, fundingtx, funding_broadcast_failed_or_success);
/* Mark consumed outputs as spent */
wallet_confirm_utxos(ld->wallet, fc->wtx->utxos);
wallet_transaction_annotate(ld->wallet, &funding_txid,
TX_CHANNEL_FUNDING, channel->dbid);
/* We need these to compose cmd's response in funding_broadcast_success */
fc->hextx = tal_hex(fc, linearize_tx(fc->cmd, fundingtx));
return true;
}
static void opening_funder_finished(struct subd *openingd, const u8 *resp,
const int *fds,
struct funding_channel *fc)
{
struct channel_info channel_info;
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;
/* This is a new channel_info.their_config so set its ID to 0 */
channel_info.their_config.id = 0;
if (!fromwire_opening_funder_reply(resp, resp,
&channel_info.their_config,
&remote_commit,
&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 = get_chainparams(openingd->ld);
per_peer_state_set_fds_arr(pps, fds);
log_debug(ld->log,
"%s", type_to_string(tmpctx, struct pubkey,
&channel_info.remote_per_commit));
/* Steals fields from uc */
channel = wallet_commit_channel(ld, fc->uc,
remote_commit,
&remote_commit_sig,
&funding_txid,
funding_txout,
fc->funding,
fc->push,
fc->channel_flags,
&channel_info,
feerate,
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);
/* Needed for the success statement */
derive_channel_id(&fc->cid, &channel->funding_txid, funding_txout);
/* Was this an external wallet initiation ? */
if (fc->inflight) {
funding_success(channel);
peer_start_channeld(channel, pps, NULL, false);
goto cleanup;
}
if (!compose_and_broadcast_tx(ld, resp, fc, &channel_info,
channel, &funding_txid,
feerate))
goto cleanup;
/* Start normal channel daemon. */
peer_start_channeld(channel, pps, NULL, false);
subd_release_channel(openingd, fc->uc);
fc->uc->openingd = NULL;
return;
cleanup:
subd_release_channel(openingd, fc->uc);
fc->uc->openingd = 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)
{
u8 *funding_signed;
struct channel_info channel_info;
struct bitcoin_signature remote_commit_sig;
struct bitcoin_tx *remote_commit;
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;
struct per_peer_state *pps;
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_opening_fundee(tmpctx, reply,
&channel_info.their_config,
&remote_commit,
&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,
&funding_signed,
&uc->our_config.channel_reserve,
&remote_upfront_shutdown_script)) {
log_broken(uc->log, "bad OPENING_FUNDEE_REPLY %s",
tal_hex(reply, reply));
uncommitted_channel_disconnect(uc, "bad OPENING_FUNDEE_REPLY");
goto failed;
}
remote_commit->chainparams = get_chainparams(openingd->ld);
per_peer_state_set_fds_arr(pps, fds);
/* openingd should never accept them funding channel in this case. */
if (peer_active_channel(uc->peer)) {
log_broken(uc->log, "openingd accepted peer funding channel");
uncommitted_channel_disconnect(uc, "already have active channel");
goto failed;
}
/* Consumes uc */
channel = wallet_commit_channel(ld, uc,
remote_commit,
&remote_commit_sig,
&funding_txid,
funding_outnum,
funding,
push,
channel_flags,
&channel_info,
feerate,
remote_upfront_shutdown_script);
if (!channel) {
uncommitted_channel_disconnect(uc, "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);
/* On to normal operation! */
peer_start_channeld(channel, pps, funding_signed, false);
subd_release_channel(openingd, uc);
uc->openingd = NULL;
tal_free(uc);
return;
failed:
close(fds[0]);
close(fds[1]);
close(fds[3]);
tal_free(uc);
}
static void opening_funder_failed(struct subd *openingd, const u8 *msg,
struct uncommitted_channel *uc)
{
char *desc;
if (!fromwire_opening_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;
}
/* 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. */
uc->fc = tal_free(uc->fc);
}
static void opening_channel_errmsg(struct uncommitted_channel *uc,
struct per_peer_state *pps,
const struct channel_id *channel_id UNUSED,
const char *desc,
bool soft_error UNUSED,
const u8 *err_for_them UNUSED)
{
/* Close fds, if any. */
tal_free(pps);
uncommitted_channel_disconnect(uc, desc);
tal_free(uc);
}
/* There's nothing permanent in an unconfirmed transaction */
static void opening_channel_set_billboard(struct uncommitted_channel *uc,
bool perm UNUSED,
const char *happenings TAKES)
{
uc->transient_billboard = tal_free(uc->transient_billboard);
if (happenings)
uc->transient_billboard = tal_strdup(uc, happenings);
}
static void destroy_uncommitted_channel(struct uncommitted_channel *uc)
{
if (uc->openingd) {
struct subd *openingd = uc->openingd;
uc->openingd = NULL;
subd_release_channel(openingd, uc);
}
/* This is how shutdown_subdaemons tells us not to delete from db! */
if (!uc->peer->uncommitted_channel)
return;
uc->peer->uncommitted_channel = NULL;
maybe_delete_peer(uc->peer);
}
static struct uncommitted_channel *
new_uncommitted_channel(struct peer *peer)
{
struct lightningd *ld = peer->ld;
struct uncommitted_channel *uc = tal(ld, struct uncommitted_channel);
const char *idname;
uc->peer = peer;
assert(!peer->uncommitted_channel);
uc->transient_billboard = NULL;
uc->dbid = wallet_get_channel_dbid(ld->wallet);
idname = type_to_string(uc, struct node_id, &uc->peer->id);
uc->log = new_log(uc, uc->peer->log_book, "%s chan #%"PRIu64":",
idname, uc->dbid);
tal_free(idname);
uc->fc = NULL;
uc->our_config.id = 0;
get_channel_basepoints(ld, &uc->peer->id, uc->dbid,
&uc->local_basepoints, &uc->local_funding_pubkey);
uc->peer->uncommitted_channel = uc;
tal_add_destructor(uc, destroy_uncommitted_channel);
return uc;
}
static void channel_config(struct lightningd *ld,
struct channel_config *ours,
u32 *max_to_self_delay,
struct amount_msat *min_effective_htlc_capacity)
{
struct amount_msat dust_limit;
/* FIXME: depend on feerate. */
*max_to_self_delay = ld->config.locktime_max;
/* Take minimal effective capacity from config min_capacity_sat */
if (!amount_msat_from_sat_u64(min_effective_htlc_capacity,
ld->config.min_capacity_sat))
fatal("amount_msat overflow for config.min_capacity_sat");
/* Substract 2 * dust_limit, so fundchannel with min value is possible */
if (!amount_sat_to_msat(&dust_limit, get_chainparams(ld)->dust_limit))
fatal("amount_msat overflow for dustlimit");
if (!amount_msat_sub(min_effective_htlc_capacity,
*min_effective_htlc_capacity,
dust_limit))
*min_effective_htlc_capacity = AMOUNT_MSAT(0);
if (!amount_msat_sub(min_effective_htlc_capacity,
*min_effective_htlc_capacity,
dust_limit))
*min_effective_htlc_capacity = AMOUNT_MSAT(0);
/* BOLT #2:
*
* The sending node SHOULD:
*...
* - set `dust_limit_satoshis` to a sufficient value to allow
* commitment transactions to propagate through the Bitcoin network.
*/
ours->dust_limit = get_chainparams(ld)->dust_limit;
ours->max_htlc_value_in_flight = AMOUNT_MSAT(UINT64_MAX);
/* Don't care */
ours->htlc_minimum = AMOUNT_MSAT(0);
/* BOLT #2:
*
* The sending node SHOULD:
* - set `to_self_delay` sufficient to ensure the sender can
* irreversibly spend a commitment transaction output, in case of
* misbehavior by the receiver.
*/
ours->to_self_delay = ld->config.locktime_blocks;
/* BOLT #2:
*
* The receiving node MUST fail the channel if:
*...
* - `max_accepted_htlcs` is greater than 483.
*/
ours->max_accepted_htlcs = 483;
/* This is filled in by lightning_openingd, for consistency. */
ours->channel_reserve = AMOUNT_SAT(UINT64_MAX);
}
struct openchannel_hook_payload {
struct subd *openingd;
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;
};
static void
openchannel_hook_serialize(struct openchannel_hook_payload *payload,
struct json_stream *stream)
{
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_cb(struct openchannel_hook_payload *payload,
const char *buffer,
const jsmntok_t *toks)
{
struct subd *openingd = payload->openingd;
const char *errmsg = NULL;
/* 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 we had a hook, check what it says */
if (buffer) {
const jsmntok_t *t = json_get_member(buffer, toks, "result");
if (!t)
fatal("Plugin returned an invalid response to the"
" openchannel hook: %.*s",
toks[0].end - toks[0].start,
buffer + toks[0].start);
if (json_tok_streq(buffer, t, "reject")) {
t = json_get_member(buffer, toks, "error_message");
if (t)
errmsg = json_strdup(tmpctx, buffer, t);
else
errmsg = "";
log_debug(openingd->ld->log,
"openchannel_hook_cb says '%s'",
errmsg);
} else if (!json_tok_streq(buffer, t, "continue"))
fatal("Plugin returned an invalid result for the "
"openchannel hook: %.*s",
t->end - t->start, buffer + t->start);
}
subd_send_msg(openingd,
take(towire_opening_got_offer_reply(NULL, errmsg)));
}
REGISTER_PLUGIN_HOOK(openchannel,
openchannel_hook_cb,
struct openchannel_hook_payload *,
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_opening_got_offer_reply(NULL,
"Already have active channel")));
return;
}
payload = tal(openingd->ld, struct openchannel_hook_payload);
payload->openingd = openingd;
if (!fromwire_opening_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, payload);
}
static unsigned int openingd_msg(struct subd *openingd,
const u8 *msg, const int *fds)
{
enum opening_wire_type t = fromwire_peektype(msg);
struct uncommitted_channel *uc = openingd->channel;
switch (t) {
case WIRE_OPENING_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_OPENING_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_OPENING_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_OPENING_FUNDEE:
if (tal_count(fds) != 3)
return 3;
opening_fundee_finished(openingd, msg, fds, uc);
return 0;
case WIRE_OPENING_GOT_OFFER:
opening_got_offer(openingd, msg, uc);
return 0;
/* We send these! */
case WIRE_OPENING_INIT:
case WIRE_OPENING_FUNDER:
case WIRE_OPENING_FUNDER_START:
case WIRE_OPENING_FUNDER_COMPLETE:
case WIRE_OPENING_FUNDER_CANCEL:
case WIRE_OPENING_GOT_OFFER_REPLY:
case WIRE_OPENING_DEV_MEMLEAK:
/* Replies never get here */
case WIRE_OPENING_DEV_MEMLEAK_REPLY:
break;
}
log_broken(openingd->log, "Unexpected msg %s: %s",
opening_wire_type_name(t), tal_hex(tmpctx, msg));
tal_free(openingd);
return 0;
}
void peer_start_openingd(struct peer *peer,
struct per_peer_state *pps,
const u8 *send_msg)
{
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->openingd = new_channel_subd(peer->ld,
"lightning_openingd",
uc, uc->log,
true, opening_wire_type_name,
openingd_msg,
opening_channel_errmsg,
opening_channel_set_billboard,
take(&pps->peer_fd),
take(&pps->gossip_fd),
take(&pps->gossip_store_fd),
take(&hsmfd), NULL);
if (!uc->openingd) {
uncommitted_channel_disconnect(uc,
tal_fmt(tmpctx,
"Running lightning_openingd: %s",
strerror(errno)));
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_opening_init(NULL,
&get_chainparams(peer->ld)->genesis_blockhash,
&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->localfeatures,
send_msg);
subd_send_msg(uc->openingd, take(msg));
}
static struct command_result *json_fund_channel_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;
u32 *funding_txout_num;
u16 funding_txout;
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();
if (*funding_txout_num > UINT16_MAX)
return command_fail(cmd, LIGHTNINGD,
"Invalid parameter: funding tx vout too large %u",
*funding_txout_num);
funding_txout = *funding_txout_num;
peer = peer_by_id(cmd->ld, id);
if (!peer) {
return command_fail(cmd, LIGHTNINGD, "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, LIGHTNINGD, "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.");
/* Set the cmd to this new cmd */
peer->uncommitted_channel->fc->cmd = cmd;
msg = towire_opening_funder_complete(NULL,
funding_txid,
funding_txout);
subd_send_msg(peer->uncommitted_channel->openingd, take(msg));
return command_still_pending(cmd);
}
/**
* json_fund_channel_cancel - Entrypoint for cancelling an in flight channel-funding
*/
static struct command_result *json_fund_channel_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, LIGHTNINGD, "Unknown peer");
}
if (!peer->uncommitted_channel) {
return command_fail(cmd, LIGHTNINGD, "Peer not connected");
}
if (!peer->uncommitted_channel->fc || !peer->uncommitted_channel->fc->inflight)
return command_fail(cmd, LIGHTNINGD, "No channel funding in progress.");
/**
* there's a question of 'state machinery' here. as is, we're not checking
* to see if you've already called `complete` -- we expect you
* the caller to EITHER pick 'complete' or 'cancel'.
* but if for some reason you've decided to test your luck, how much
* 'handling' can we do for that case? the easiest thing to do is to
* say "sorry you've already called complete", we can't cancel this.
*
* there's also the state you might end up in where you've called
* complete (and it's completed and been passed off to channeld) but
* you've decided (for whatever reason) not to broadcast the transaction
* so your channels have ended up in this 'waiting' state. neither of us
* are actually out any amount of cash, but it'd be nice if there's a way
* to signal to c-lightning (+ your peer) that this channel is dead on arrival.
* ... but also if you then broadcast this tx you'd be in trouble cuz we're
* both going to forget about it. the meta question here is how 'undoable'
* should we make any of this. how much tools do we give you, reader?
*
* for now, let's settle for the EITHER / OR case and disregard the larger
* question about 'how long cancelable'.
*/
/* Make sure this gets notified if we succeed or cancel */
tal_arr_expand(&peer->uncommitted_channel->fc->cancels, cmd);
msg = towire_opening_funder_cancel(NULL);
subd_send_msg(peer->uncommitted_channel->openingd, take(msg));
return command_still_pending(cmd);
}
/**
* json_fund_channel_start - Entrypoint for funding an externally funded channel
*/
static struct command_result *json_fund_channel_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 max_funding_satoshi, *amount;
max_funding_satoshi = get_chainparams(cmd->ld)->max_funding;
fc->cmd = cmd;
fc->cancels = tal_arr(fc, struct command *, 0);
fc->uc = NULL;
fc->inflight = false;
if (!param(fc->cmd, buffer, params,
p_req("id", param_node_id, &id),
p_req("satoshi", param_sat, &amount),
p_opt("feerate", param_feerate, &feerate_per_kw),
p_opt_def("announce", param_bool, &announce_channel, true),
NULL))
return command_param_failed();
if (amount_sat_greater(*amount, max_funding_satoshi))
return command_fail(cmd, FUND_MAX_EXCEEDED,
"Amount exceeded %s",
type_to_string(tmpctx, struct amount_sat,
&max_funding_satoshi));
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");
}
peer = peer_by_id(cmd->ld, id);
if (!peer) {
return command_fail(cmd, LIGHTNINGD, "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, LIGHTNINGD, "Peer not connected");
}
if (peer->uncommitted_channel->fc) {
return command_fail(cmd, LIGHTNINGD, "Already funding channel");
}
fc->push = 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));
}
assert(!amount_sat_greater(*amount, max_funding_satoshi));
peer->uncommitted_channel->fc = tal_steal(peer->uncommitted_channel, fc);
fc->uc = peer->uncommitted_channel;
msg = towire_opening_funder_start(NULL,
*amount,
fc->push,
*feerate_per_kw,
fc->channel_flags);
subd_send_msg(peer->uncommitted_channel->openingd, take(msg));
return command_still_pending(cmd);
}
/**
* json_fund_channel - Entrypoint for funding a channel
*/
static struct command_result *json_fund_channel(struct command *cmd,
const char *buffer,
const jsmntok_t *obj UNNEEDED,
const jsmntok_t *params)
{
struct command_result *res;
struct funding_channel * fc = tal(cmd, struct funding_channel);
struct node_id *id;
struct peer *peer;
struct channel *channel;
u32 *feerate_per_kw, *minconf, maxheight;
bool *announce_channel;
u8 *msg;
struct amount_sat max_funding_satoshi;
const struct utxo **chosen_utxos;
max_funding_satoshi = get_chainparams(cmd->ld)->max_funding;
fc->cmd = cmd;
fc->cancels = tal_arr(fc, struct command *, 0);
fc->uc = NULL;
fc->inflight = false;
fc->wtx = tal(fc, struct wallet_tx);
wtx_init(cmd, fc->wtx, max_funding_satoshi);
if (!param(fc->cmd, buffer, params,
p_req("id", param_node_id, &id),
p_req("satoshi", param_wtx, fc->wtx),
p_opt("feerate", param_feerate, &feerate_per_kw),
p_opt_def("announce", param_bool, &announce_channel, true),
p_opt_def("minconf", param_number, &minconf, 1),
p_opt("utxos", param_utxos, &chosen_utxos),
NULL))
return command_param_failed();
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");
}
peer = peer_by_id(cmd->ld, id);
if (!peer) {
return command_fail(cmd, LIGHTNINGD, "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, LIGHTNINGD, "Peer not connected");
}
if (peer->uncommitted_channel->fc) {
return command_fail(cmd, LIGHTNINGD, "Already funding channel");
}
/* FIXME: Support push_msat? */
fc->push = 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));
}
maxheight = minconf_to_maxheight(*minconf, cmd->ld);
if (chosen_utxos)
res = wtx_from_utxos(fc->wtx, *feerate_per_kw,
BITCOIN_SCRIPTPUBKEY_P2WSH_LEN, maxheight, chosen_utxos);
else
res = wtx_select_utxos(fc->wtx, *feerate_per_kw,
BITCOIN_SCRIPTPUBKEY_P2WSH_LEN, maxheight);
if (res)
return res;
assert(!amount_sat_greater(fc->wtx->amount, max_funding_satoshi));
/* Stash total amount in fc as well, as externally funded
* channels don't have a wtx */
fc->funding = fc->wtx->amount;
peer->uncommitted_channel->fc = tal_steal(peer->uncommitted_channel, fc);
fc->uc = peer->uncommitted_channel;
msg = towire_opening_funder(NULL,
fc->wtx->amount,
fc->push,
*feerate_per_kw,
fc->wtx->change,
fc->wtx->change_key_index,
fc->channel_flags,
fc->wtx->utxos,
cmd->ld->wallet->bip32_base);
/* Openingd will either succeed, or fail, or tell us the other side
* funded first. */
subd_send_msg(peer->uncommitted_channel->openingd, take(msg));
return command_still_pending(cmd);
}
static const struct json_command fund_channel_command = {
"fundchannel",
"channels",
json_fund_channel,
"Fund channel with {id} using {satoshi} (or 'all') satoshis, at optional "
"{feerate}. Only use outputs that have {minconf} confirmations."
};
AUTODATA(json_command, &fund_channel_command);
static const struct json_command fund_channel_start_command = {
"fundchannel_start",
"channels",
json_fund_channel_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, &fund_channel_start_command);
static const struct json_command fund_channel_cancel_command = {
"fundchannel_cancel",
"channels",
json_fund_channel_cancel,
"Cancel inflight channel establishment with peer {id}."
};
AUTODATA(json_command, &fund_channel_cancel_command);
static const struct json_command fund_channel_complete_command = {
"fundchannel_complete",
"channels",
json_fund_channel_complete,
"Complete channel establishment with peer {id} for funding transaction"
"with {txid}. Returns true on success, false otherwise."
};
AUTODATA(json_command, &fund_channel_complete_command);
#if DEVELOPER
/* Indented to avoid include ordering check */
#include <lightningd/memdump.h>
static void opening_died_forget_memleak(struct subd *openingd,
struct command *cmd)
{
/* FIXME: We ignore the remaining openingds in this case. */
opening_memleak_done(cmd, NULL);
}
/* Mutual recursion */
static void opening_memleak_req_next(struct command *cmd, struct peer *prev);
static void opening_memleak_req_done(struct subd *openingd,
const u8 *msg, const int *fds UNUSED,
struct command *cmd)
{
bool found_leak;
struct uncommitted_channel *uc = openingd->channel;
tal_del_destructor2(openingd, opening_died_forget_memleak, cmd);
if (!fromwire_opening_dev_memleak_reply(msg, &found_leak)) {
was_pending(command_fail(cmd, LIGHTNINGD,
"Bad opening_dev_memleak"));
return;
}
if (found_leak) {
opening_memleak_done(cmd, openingd);
return;
}
opening_memleak_req_next(cmd, uc->peer);
}
static void opening_memleak_req_next(struct command *cmd, struct peer *prev)
{
struct peer *p;
list_for_each(&cmd->ld->peers, p, list) {
if (!p->uncommitted_channel)
continue;
if (p == prev) {
prev = NULL;
continue;
}
if (prev != NULL)
continue;
subd_req(p,
p->uncommitted_channel->openingd,
take(towire_opening_dev_memleak(NULL)),
-1, 0, opening_memleak_req_done, cmd);
/* Just in case it dies before replying! */
tal_add_destructor2(p->uncommitted_channel->openingd,
opening_died_forget_memleak, cmd);
return;
}
opening_memleak_done(cmd, NULL);
}
void opening_dev_memleak(struct command *cmd)
{
opening_memleak_req_next(cmd, NULL);
}
#endif /* DEVELOPER */