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#include <bitcoin/script.h>
#include <ccan/fdpass/fdpass.h>
#include <closingd/gen_closing_wire.h>
#include <common/close_tx.h>
#include <common/closing_fee.h>
#include <common/crypto_sync.h>
#include <common/derive_basepoints.h>
#include <common/htlc.h>
#include <common/memleak.h>
#include <common/peer_billboard.h>
#include <common/peer_failed.h>
#include <common/per_peer_state.h>
#include <common/read_peer_msg.h>
#include <common/socket_close.h>
#include <common/status.h>
#include <common/subdaemon.h>
#include <common/type_to_string.h>
#include <common/utils.h>
#include <common/version.h>
#include <common/wire_error.h>
#include <errno.h>
#include <gossipd/gen_gossip_peerd_wire.h>
#include <hsmd/gen_hsm_wire.h>
#include <inttypes.h>
#include <stdio.h>
#include <unistd.h>
#include <wire/peer_wire.h>
#include <wire/wire_sync.h>
/* stdin == requests, 3 == peer, 4 = gossip, 5 = gossip_store, 6 = hsmd */
#define REQ_FD STDIN_FILENO
#define HSM_FD 6
static struct bitcoin_tx *close_tx(const tal_t *ctx,
const struct chainparams *chainparams,
struct per_peer_state *pps,
const struct channel_id *channel_id,
u8 *scriptpubkey[NUM_SIDES],
const struct bitcoin_txid *funding_txid,
unsigned int funding_txout,
struct amount_sat funding,
const u8 *funding_wscript,
const struct amount_sat out[NUM_SIDES],
enum side opener,
struct amount_sat fee,
struct amount_sat dust_limit)
{
struct bitcoin_tx *tx;
struct amount_sat out_minus_fee[NUM_SIDES];
out_minus_fee[LOCAL] = out[LOCAL];
out_minus_fee[REMOTE] = out[REMOTE];
if (!amount_sat_sub(&out_minus_fee[opener], out[opener], fee))
peer_failed(pps, channel_id,
"Funder cannot afford fee %s (%s and %s)",
type_to_string(tmpctx, struct amount_sat, &fee),
type_to_string(tmpctx, struct amount_sat,
&out[LOCAL]),
type_to_string(tmpctx, struct amount_sat,
&out[REMOTE]));
status_debug("Making close tx at = %s/%s fee %s",
type_to_string(tmpctx, struct amount_sat, &out[LOCAL]),
type_to_string(tmpctx, struct amount_sat, &out[REMOTE]),
type_to_string(tmpctx, struct amount_sat, &fee));
/* FIXME: We need to allow this! */
tx = create_close_tx(ctx,
chainparams,
scriptpubkey[LOCAL], scriptpubkey[REMOTE],
funding_wscript,
funding_txid,
funding_txout,
funding,
out_minus_fee[LOCAL],
out_minus_fee[REMOTE],
dust_limit);
if (!tx)
peer_failed(pps, channel_id,
"Both outputs below dust limit:"
" funding = %s"
" fee = %s"
" dust_limit = %s"
" LOCAL = %s"
" REMOTE = %s",
type_to_string(tmpctx, struct amount_sat, &funding),
type_to_string(tmpctx, struct amount_sat, &fee),
type_to_string(tmpctx, struct amount_sat, &dust_limit),
type_to_string(tmpctx, struct amount_sat, &out[LOCAL]),
type_to_string(tmpctx, struct amount_sat, &out[REMOTE]));
return tx;
}
/* Handle random messages we might get, returning the first non-handled one. */
static u8 *closing_read_peer_msg(const tal_t *ctx,
struct per_peer_state *pps,
const struct channel_id *channel_id)
{
for (;;) {
u8 *msg;
bool from_gossipd;
clean_tmpctx();
msg = peer_or_gossip_sync_read(ctx, pps, &from_gossipd);
if (from_gossipd) {
handle_gossip_msg(pps, take(msg));
continue;
}
if (!handle_peer_gossip_or_error(pps, channel_id, false, msg))
return msg;
}
}
static struct pubkey get_per_commitment_point(u64 commitment_number)
{
u8 *msg;
struct pubkey commitment_point;
struct secret *s;
/* Our current per-commitment point is the commitment point in the last
* received signed commitment; HSM gives us that and the previous
* secret (which we don't need). */
msg = towire_hsm_get_per_commitment_point(NULL,
commitment_number);
if (!wire_sync_write(HSM_FD, take(msg)))
status_failed(STATUS_FAIL_HSM_IO,
"Writing get_per_commitment_point to HSM: %s",
strerror(errno));
msg = wire_sync_read(tmpctx, HSM_FD);
if (!msg)
status_failed(STATUS_FAIL_HSM_IO,
"Reading resp get_per_commitment_point reply: %s",
strerror(errno));
if (!fromwire_hsm_get_per_commitment_point_reply(tmpctx, msg,
&commitment_point,
&s))
status_failed(STATUS_FAIL_HSM_IO,
"Bad per_commitment_point reply %s",
tal_hex(tmpctx, msg));
return commitment_point;
}
static void do_reconnect(struct per_peer_state *pps,
const struct channel_id *channel_id,
const u64 next_index[NUM_SIDES],
u64 revocations_received,
const u8 *channel_reestablish,
const u8 *final_scriptpubkey,
const struct secret *last_remote_per_commit_secret)
{
u8 *msg;
struct channel_id their_channel_id;
u64 next_local_commitment_number, next_remote_revocation_number;
struct pubkey my_current_per_commitment_point, next_commitment_point;
my_current_per_commitment_point = get_per_commitment_point(next_index[LOCAL]-1);
/* BOLT #2:
*
* - upon reconnection:
* - if a channel is in an error state:
* - SHOULD retransmit the error packet and ignore any other packets for
* that channel.
* - otherwise:
* - MUST transmit `channel_reestablish` for each channel.
* - MUST wait to receive the other node's `channel_reestablish`
* message before sending any other messages for that channel.
*
* The sending node:
* - MUST set `next_commitment_number` to the commitment number
* of the next `commitment_signed` it expects to receive.
* - MUST set `next_revocation_number` to the commitment number
* of the next `revoke_and_ack` message it expects to receive.
*/
/* We're always allowed to send extra fields, so we send dataloss_protect
* even if we didn't negotiate it */
msg = towire_channel_reestablish_option_data_loss_protect(NULL, channel_id,
next_index[LOCAL],
revocations_received,
last_remote_per_commit_secret,
&my_current_per_commitment_point);
sync_crypto_write(pps, take(msg));
/* They might have already sent reestablish, which triggered us */
if (!channel_reestablish) {
do {
tal_free(channel_reestablish);
channel_reestablish = closing_read_peer_msg(tmpctx, pps,
channel_id);
/* They *should* send reestablish first, but lnd
* sends other messages, which we can ignore since
* we're closing anyway... */
} while (fromwire_peektype(channel_reestablish)
!= WIRE_CHANNEL_REESTABLISH);
}
if (!fromwire_channel_reestablish(channel_reestablish, &their_channel_id,
&next_local_commitment_number,
&next_remote_revocation_number)) {
peer_failed(pps, channel_id,
"bad reestablish msg: %s %s",
wire_type_name(fromwire_peektype(channel_reestablish)),
tal_hex(tmpctx, channel_reestablish));
}
status_debug("Got reestablish commit=%"PRIu64" revoke=%"PRIu64,
next_local_commitment_number,
next_remote_revocation_number);
/* BOLT #2:
*
* A node:
*...
* - upon reconnection:
* - if it has sent a previous `shutdown`:
* - MUST retransmit `shutdown`.
*/
msg = towire_shutdown(NULL, channel_id, final_scriptpubkey);
sync_crypto_write(pps, take(msg));
/* BOLT #2:
*
* A node:
*...
* - if `next_commitment_number` is 1 in both the `channel_reestablish` it sent and received:
* - MUST retransmit `funding_locked`.
*/
if (next_index[REMOTE] == 1 && next_index[LOCAL] == 1) {
status_debug("Retransmitting funding_locked for channel %s",
type_to_string(tmpctx, struct channel_id, channel_id));
next_commitment_point = get_per_commitment_point(next_index[LOCAL]);
msg = towire_funding_locked(NULL, channel_id, &next_commitment_point);
sync_crypto_write(pps, take(msg));
}
}
static void send_offer(struct per_peer_state *pps,
const struct chainparams *chainparams,
const struct channel_id *channel_id,
const struct pubkey funding_pubkey[NUM_SIDES],
const u8 *funding_wscript,
u8 *scriptpubkey[NUM_SIDES],
const struct bitcoin_txid *funding_txid,
unsigned int funding_txout,
struct amount_sat funding,
const struct amount_sat out[NUM_SIDES],
enum side opener,
struct amount_sat our_dust_limit,
struct amount_sat fee_to_offer)
{
struct bitcoin_tx *tx;
struct bitcoin_signature our_sig;
u8 *msg;
/* BOLT #2:
*
* - MUST set `signature` to the Bitcoin signature of the close
* transaction, as specified in [BOLT
* #3](03-transactions.md#closing-transaction).
*/
tx = close_tx(tmpctx, chainparams, pps, channel_id,
scriptpubkey,
funding_txid,
funding_txout,
funding,
funding_wscript,
out,
opener, fee_to_offer, our_dust_limit);
/* BOLT #3:
*
* ## Closing Transaction
*...
* Each node offering a signature... MAY eliminate its
* own output.
*/
/* (We don't do this). */
wire_sync_write(HSM_FD,
take(towire_hsm_sign_mutual_close_tx(NULL,
tx,
&funding_pubkey[REMOTE])));
msg = wire_sync_read(tmpctx, HSM_FD);
if (!fromwire_hsm_sign_tx_reply(msg, &our_sig))
status_failed(STATUS_FAIL_HSM_IO,
"Bad hsm_sign_mutual_close_tx reply %s",
tal_hex(tmpctx, msg));
status_debug("sending fee offer %s",
type_to_string(tmpctx, struct amount_sat, &fee_to_offer));
assert(our_sig.sighash_type == SIGHASH_ALL);
msg = towire_closing_signed(NULL, channel_id, fee_to_offer, &our_sig.s);
sync_crypto_write(pps, take(msg));
}
static void tell_master_their_offer(const struct bitcoin_signature *their_sig,
const struct bitcoin_tx *tx,
struct bitcoin_txid *tx_id)
{
u8 *msg = towire_closing_received_signature(NULL, their_sig, tx);
if (!wire_sync_write(REQ_FD, take(msg)))
status_failed(STATUS_FAIL_MASTER_IO,
"Writing received to master: %s",
strerror(errno));
/* Wait for master to ack, to make sure it's in db. */
msg = wire_sync_read(NULL, REQ_FD);
if (!fromwire_closing_received_signature_reply(msg, tx_id))
master_badmsg(WIRE_CLOSING_RECEIVED_SIGNATURE_REPLY, msg);
tal_free(msg);
}
/* Returns fee they offered. */
static struct amount_sat
receive_offer(struct per_peer_state *pps,
const struct chainparams *chainparams,
const struct channel_id *channel_id,
const struct pubkey funding_pubkey[NUM_SIDES],
const u8 *funding_wscript,
u8 *scriptpubkey[NUM_SIDES],
const struct bitcoin_txid *funding_txid,
unsigned int funding_txout,
struct amount_sat funding,
const struct amount_sat out[NUM_SIDES],
enum side opener,
struct amount_sat our_dust_limit,
struct amount_sat min_fee_to_accept,
struct bitcoin_txid *closing_txid)
{
u8 *msg;
struct channel_id their_channel_id;
struct amount_sat received_fee;
struct bitcoin_signature their_sig;
struct bitcoin_tx *tx;
/* Wait for them to say something interesting */
do {
msg = closing_read_peer_msg(tmpctx, pps, channel_id);
/* BOLT #2:
*
* - upon reconnection:
* - MUST ignore any redundant `funding_locked` it receives.
*/
/* This should only happen if we've made no commitments, but
* we don't have to check that: it's their problem. */
if (fromwire_peektype(msg) == WIRE_FUNDING_LOCKED)
msg = tal_free(msg);
/* BOLT #2:
* - if it has sent a previous `shutdown`:
* - MUST retransmit `shutdown`.
*/
else if (fromwire_peektype(msg) == WIRE_SHUTDOWN)
msg = tal_free(msg);
} while (!msg);
their_sig.sighash_type = SIGHASH_ALL;
if (!fromwire_closing_signed(msg, &their_channel_id,
&received_fee, &their_sig.s))
peer_failed(pps, channel_id,
"Expected closing_signed: %s",
tal_hex(tmpctx, msg));
/* BOLT #2:
*
* The receiving node:
* - if the `signature` is not valid for either variant of closing transaction
* specified in [BOLT #3](03-transactions.md#closing-transaction):
* - MUST fail the connection.
*/
tx = close_tx(tmpctx, chainparams, pps, channel_id,
scriptpubkey,
funding_txid,
funding_txout,
funding,
funding_wscript,
out, opener, received_fee, our_dust_limit);
if (!check_tx_sig(tx, 0, NULL, funding_wscript,
&funding_pubkey[REMOTE], &their_sig)) {
/* Trim it by reducing their output to minimum */
struct bitcoin_tx *trimmed;
struct amount_sat trimming_out[NUM_SIDES];
if (opener == REMOTE)
trimming_out[REMOTE] = received_fee;
else
trimming_out[REMOTE] = AMOUNT_SAT(0);
trimming_out[LOCAL] = out[LOCAL];
/* BOLT #3:
*
* Each node offering a signature:
* - MUST round each output down to whole satoshis.
* - MUST subtract the fee given by `fee_satoshis` from the
* output to the funder.
* - MUST remove any output below its own
* `dust_limit_satoshis`.
* - MAY eliminate its own output.
*/
trimmed = close_tx(tmpctx, chainparams, pps, channel_id,
scriptpubkey,
funding_txid,
funding_txout,
funding,
funding_wscript,
trimming_out,
opener, received_fee, our_dust_limit);
if (!trimmed
|| !check_tx_sig(trimmed, 0, NULL, funding_wscript,
&funding_pubkey[REMOTE], &their_sig)) {
peer_failed(pps, channel_id,
"Bad closing_signed signature for"
" %s (and trimmed version %s)",
type_to_string(tmpctx,
struct bitcoin_tx,
tx),
trimmed ?
type_to_string(tmpctx,
struct bitcoin_tx,
trimmed)
: "NONE");
}
tx = trimmed;
}
status_debug("Received fee offer %s",
type_to_string(tmpctx, struct amount_sat, &received_fee));
/* Master sorts out what is best offer, we just tell it any above min */
if (amount_sat_greater_eq(received_fee, min_fee_to_accept)) {
status_debug("...offer is reasonable");
tell_master_their_offer(&their_sig, tx, closing_txid);
}
return received_fee;
}
struct feerange {
enum side higher_side;
struct amount_sat min, max;
};
static void init_feerange(struct feerange *feerange,
struct amount_sat commitment_fee,
const struct amount_sat offer[NUM_SIDES])
{
feerange->min = AMOUNT_SAT(0);
/* BOLT #2:
*
* - MUST set `fee_satoshis` less than or equal to the base
* fee of the final commitment transaction, as calculated
* in [BOLT #3](03-transactions.md#fee-calculation).
*/
feerange->max = commitment_fee;
if (amount_sat_greater(offer[LOCAL], offer[REMOTE]))
feerange->higher_side = LOCAL;
else
feerange->higher_side = REMOTE;
status_debug("Feerange init %s-%s, %s higher",
type_to_string(tmpctx, struct amount_sat, &feerange->min),
type_to_string(tmpctx, struct amount_sat, &feerange->max),
feerange->higher_side == LOCAL ? "local" : "remote");
}
static void adjust_feerange(struct feerange *feerange,
struct amount_sat offer, enum side side)
{
bool ok;
/* BOLT #2:
*
* - MUST propose a value "strictly between" the received
* `fee_satoshis` and its previously-sent `fee_satoshis`.
*/
if (side == feerange->higher_side)
ok = amount_sat_sub(&feerange->max, offer, AMOUNT_SAT(1));
else
ok = amount_sat_add(&feerange->min, offer, AMOUNT_SAT(1));
status_debug("Feerange %s update %s: now %s-%s",
side == LOCAL ? "local" : "remote",
type_to_string(tmpctx, struct amount_sat, &offer),
type_to_string(tmpctx, struct amount_sat, &feerange->min),
type_to_string(tmpctx, struct amount_sat, &feerange->max));
if (!ok)
status_failed(STATUS_FAIL_INTERNAL_ERROR,
"Overflow in updating fee range");
}
/* Figure out what we should offer now. */
static struct amount_sat
adjust_offer(struct per_peer_state *pps, const struct channel_id *channel_id,
const struct feerange *feerange, struct amount_sat remote_offer,
struct amount_sat min_fee_to_accept, u64 fee_negotiation_step,
u8 fee_negotiation_step_unit)
{
struct amount_sat min_plus_one, range_len, step_sat, result;
struct amount_msat step_msat;
/* Within 1 satoshi? Agree. */
if (!amount_sat_add(&min_plus_one, feerange->min, AMOUNT_SAT(1)))
peer_failed(pps, channel_id,
"Fee offer %s min too large",
type_to_string(tmpctx, struct amount_sat,
&feerange->min));
if (amount_sat_greater_eq(min_plus_one, feerange->max))
return remote_offer;
/* feerange has already been adjusted so that our new offer is ok to be
* any number in [feerange->min, feerange->max] and after the following
* min_fee_to_accept is in that range. Thus, pick a fee in
* [min_fee_to_accept, feerange->max]. */
if (amount_sat_greater(feerange->min, min_fee_to_accept))
min_fee_to_accept = feerange->min;
/* Max is below our minimum acceptable? */
if (!amount_sat_sub(&range_len, feerange->max, min_fee_to_accept))
peer_failed(pps, channel_id,
"Feerange %s-%s"
" below minimum acceptable %s",
type_to_string(tmpctx, struct amount_sat,
&feerange->min),
type_to_string(tmpctx, struct amount_sat,
&feerange->max),
type_to_string(tmpctx, struct amount_sat,
&min_fee_to_accept));
if (fee_negotiation_step_unit ==
CLOSING_FEE_NEGOTIATION_STEP_UNIT_SATOSHI) {
/* -1 because the range boundary has already been adjusted with
* one from our previous proposal. So, if the user requested a
* step of 1 satoshi at a time we should just return our end of
* the range from this function. */
amount_msat_from_u64(&step_msat,
(fee_negotiation_step - 1) * MSAT_PER_SAT);
} else {
/* fee_negotiation_step is e.g. 20 to designate 20% from
* range_len (which is in satoshi), so:
* range_len * fee_negotiation_step / 100 [sat]
* is equivalent to:
* range_len * fee_negotiation_step * 10 [msat] */
amount_msat_from_u64(&step_msat,
range_len.satoshis /* Raw: % calc */ *
fee_negotiation_step * 10);
}
step_sat = amount_msat_to_sat_round_down(step_msat);
if (feerange->higher_side == LOCAL) {
if (!amount_sat_sub(&result, feerange->max, step_sat))
/* step_sat > feerange->max, unlikely */
return min_fee_to_accept;
if (amount_sat_less_eq(result, min_fee_to_accept))
return min_fee_to_accept;
} else {
if (!amount_sat_add(&result, min_fee_to_accept, step_sat))
/* overflow, unlikely */
return feerange->max;
if (amount_sat_greater_eq(result, feerange->max))
return feerange->max;
}
return result;
}
#if DEVELOPER
/* FIXME: We should talk to lightningd anyway, rather than doing this */
static void closing_dev_memleak(const tal_t *ctx,
u8 *scriptpubkey[NUM_SIDES],
const u8 *funding_wscript)
{
struct htable *memtable;
memtable = memleak_enter_allocations(tmpctx,
scriptpubkey[LOCAL],
scriptpubkey[REMOTE]);
/* Now delete known pointers (these aren't really roots, just
* pointers we know are referenced).*/
memleak_remove_referenced(memtable, ctx);
memleak_remove_referenced(memtable, funding_wscript);
dump_memleak(memtable);
}
#endif /* DEVELOPER */
int main(int argc, char *argv[])
{
setup_locale();
const tal_t *ctx = tal(NULL, char);
struct per_peer_state *pps;
u8 *msg;
struct pubkey funding_pubkey[NUM_SIDES];
struct bitcoin_txid funding_txid, closing_txid;
u16 funding_txout;
struct amount_sat funding, out[NUM_SIDES];
struct amount_sat our_dust_limit;
struct amount_sat min_fee_to_accept, commitment_fee, offer[NUM_SIDES];
struct feerange feerange;
enum side opener;
u8 *scriptpubkey[NUM_SIDES], *funding_wscript;
u64 fee_negotiation_step;
u8 fee_negotiation_step_unit;
char fee_negotiation_step_str[32]; /* fee_negotiation_step + "sat" */
struct channel_id channel_id;
bool reconnected;
u64 next_index[NUM_SIDES], revocations_received;
enum side whose_turn;
u8 *channel_reestablish;
struct secret last_remote_per_commit_secret;
subdaemon_setup(argc, argv);
status_setup_sync(REQ_FD);
msg = wire_sync_read(tmpctx, REQ_FD);
if (!fromwire_closing_init(ctx, msg,
&chainparams,
&pps,
&funding_txid, &funding_txout,
&funding,
&funding_pubkey[LOCAL],
&funding_pubkey[REMOTE],
&opener,
&out[LOCAL],
&out[REMOTE],
&our_dust_limit,
&min_fee_to_accept, &commitment_fee,
&offer[LOCAL],
&scriptpubkey[LOCAL],
&scriptpubkey[REMOTE],
&fee_negotiation_step,
&fee_negotiation_step_unit,
&reconnected,
&next_index[LOCAL],
&next_index[REMOTE],
&revocations_received,
&channel_reestablish,
&last_remote_per_commit_secret,
&dev_fast_gossip))
master_badmsg(WIRE_CLOSING_INIT, msg);
/* stdin == requests, 3 == peer, 4 = gossip, 5 = gossip_store, 6 = hsmd */
per_peer_state_set_fds(pps, 3, 4, 5);
snprintf(fee_negotiation_step_str, sizeof(fee_negotiation_step_str),
"%" PRIu64 "%s", fee_negotiation_step,
fee_negotiation_step_unit ==
CLOSING_FEE_NEGOTIATION_STEP_UNIT_PERCENTAGE
? "%"
: "sat");
status_debug("out = %s/%s",
type_to_string(tmpctx, struct amount_sat, &out[LOCAL]),
type_to_string(tmpctx, struct amount_sat, &out[REMOTE]));
status_debug("dustlimit = %s",
type_to_string(tmpctx, struct amount_sat, &our_dust_limit));
status_debug("fee = %s",
type_to_string(tmpctx, struct amount_sat, &offer[LOCAL]));
status_debug("fee negotiation step = %s", fee_negotiation_step_str);
derive_channel_id(&channel_id, &funding_txid, funding_txout);
funding_wscript = bitcoin_redeem_2of2(ctx,
&funding_pubkey[LOCAL],
&funding_pubkey[REMOTE]);
if (reconnected)
do_reconnect(pps, &channel_id,
next_index, revocations_received,
channel_reestablish, scriptpubkey[LOCAL],
&last_remote_per_commit_secret);
peer_billboard(
true,
"Negotiating closing fee between %s and %s satoshi (ideal %s) "
"using step %s",
type_to_string(tmpctx, struct amount_sat, &min_fee_to_accept),
type_to_string(tmpctx, struct amount_sat, &commitment_fee),
type_to_string(tmpctx, struct amount_sat, &offer[LOCAL]),
fee_negotiation_step_str);
/* BOLT #2:
*
* The funding node:
* - after `shutdown` has been received, AND no HTLCs remain in either
* commitment transaction:
* - SHOULD send a `closing_signed` message.
*/
whose_turn = opener;
for (size_t i = 0; i < 2; i++, whose_turn = !whose_turn) {
if (whose_turn == LOCAL) {
send_offer(pps, chainparams,
&channel_id, funding_pubkey, funding_wscript,
scriptpubkey, &funding_txid, funding_txout,
funding, out, opener,
our_dust_limit,
offer[LOCAL]);
} else {
if (i == 0)
peer_billboard(false, "Waiting for their initial"
" closing fee offer");
else
peer_billboard(false, "Waiting for their initial"
" closing fee offer:"
" ours was %s",
type_to_string(tmpctx,
struct amount_sat,
&offer[LOCAL]));
offer[REMOTE]
= receive_offer(pps, chainparams,
&channel_id, funding_pubkey,
funding_wscript,
scriptpubkey, &funding_txid,
funding_txout, funding,
out, opener,
our_dust_limit,
min_fee_to_accept,
&closing_txid);
}
}
/* Now we have first two points, we can init fee range. */
init_feerange(&feerange, commitment_fee, offer);
/* Apply (and check) opener offer now. */
adjust_feerange(&feerange, offer[opener], opener);
/* Now any extra rounds required. */
while (!amount_sat_eq(offer[LOCAL], offer[REMOTE])) {
/* Still don't agree: adjust feerange based on previous offer */
adjust_feerange(&feerange,
offer[!whose_turn], !whose_turn);
if (whose_turn == LOCAL) {
offer[LOCAL] = adjust_offer(pps,
&channel_id,
&feerange, offer[REMOTE],
min_fee_to_accept,
fee_negotiation_step,
fee_negotiation_step_unit);
send_offer(pps, chainparams, &channel_id,
funding_pubkey, funding_wscript,
scriptpubkey, &funding_txid, funding_txout,
funding, out, opener,
our_dust_limit,
offer[LOCAL]);
} else {
peer_billboard(false, "Waiting for another"
" closing fee offer:"
" ours was %"PRIu64" satoshi,"
" theirs was %"PRIu64" satoshi,",
offer[LOCAL], offer[REMOTE]);
offer[REMOTE]
= receive_offer(pps, chainparams, &channel_id,
funding_pubkey,
funding_wscript,
scriptpubkey, &funding_txid,
funding_txout, funding,
out, opener,
our_dust_limit,
min_fee_to_accept,
&closing_txid);
}
whose_turn = !whose_turn;
}
peer_billboard(true, "We agreed on a closing fee of %"PRIu64" satoshi for tx:%s",
offer[LOCAL],
type_to_string(tmpctx, struct bitcoin_txid, &closing_txid));
#if DEVELOPER
/* We don't listen for master commands, so always check memleak here */
closing_dev_memleak(ctx, scriptpubkey, funding_wscript);
#endif
/* We're done! */
/* Properly close the channel first. */
if (!socket_close(pps->peer_fd))
status_unusual("Closing and draining peerfd gave error: %s",
strerror(errno));
/* Sending the below will kill us! */
wire_sync_write(REQ_FD, take(towire_closing_complete(NULL)));
tal_free(ctx);
daemon_shutdown();
return 0;
}