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#include <ccan/build_assert/build_assert.h>
#include <daemon/log.h>
#ifndef TEST_STATE_COVERAGE
#include <daemon/peer.h>
#endif
#include <names.h>
#include <state.h>
static enum command_status next_state(struct peer *peer,
const enum state_input input,
enum command_status cstatus,
const enum state state)
{
assert(peer->state != state);
set_peer_state(peer, state, input_name(input));
return cstatus;
}
/*
* Simple marker to note we don't update state.
*
* This happens in three cases:
* - We're ignoring packets while closing.
* - We stop watching an on-chain HTLC: we indicate that we want
* INPUT_NO_MORE_HTLCS when we get the last one.
* - HTLC add/remove in STATE_NORMAL.
*/
static enum command_status unchanged_state(const struct peer *peer,
const enum state_input input,
enum command_status cstatus)
{
log_debug(peer->log, "%s: %s unchanged",
input_name(input), state_name(peer->state));
return cstatus;
}
static void set_peer_cond(struct peer *peer, enum state_peercond cond)
{
assert(peer->cond != cond);
peer->cond = cond;
}
static void change_peer_cond(struct peer *peer,
enum state_peercond old,
enum state_peercond new)
{
assert(peer->cond == old);
peer->cond = new;
}
static void complete_cmd(struct peer *peer, enum command_status *statusp,
enum command_status status)
{
change_peer_cond(peer, PEER_BUSY, PEER_CMD_OK);
*statusp = status;
}
/* FIXME: We do this when a command succeeds instantly, and
* state is unchanged. */
static enum command_status instant_cmd_success(struct peer *peer,
enum command_status cstatus)
{
assert(peer->cond == PEER_CMD_OK);
assert(cstatus == CMD_NONE);
return CMD_SUCCESS;
}
static void queue_tx_broadcast(const struct bitcoin_tx **broadcast,
const struct bitcoin_tx *tx)
{
assert(!*broadcast);
assert(tx);
*broadcast = tx;
}
enum command_status state(struct peer *peer,
const enum state_input input,
const union input *idata,
const struct bitcoin_tx **broadcast)
{
Pkt *err;
enum command_status cstatus = CMD_NONE;
*broadcast = NULL;
switch (peer->state) {
/*
* Initial channel opening states.
*/
case STATE_INIT:
if (input_is(input, CMD_OPEN_WITH_ANCHOR)) {
queue_pkt_open(peer,
OPEN_CHANNEL__ANCHOR_OFFER__WILL_CREATE_ANCHOR);
change_peer_cond(peer, PEER_CMD_OK, PEER_BUSY);
return next_state(peer, input, cstatus,
STATE_OPEN_WAIT_FOR_OPEN_WITHANCHOR);
} else if (input_is(input, CMD_OPEN_WITHOUT_ANCHOR)) {
change_peer_cond(peer, PEER_CMD_OK, PEER_BUSY);
queue_pkt_open(peer,
OPEN_CHANNEL__ANCHOR_OFFER__WONT_CREATE_ANCHOR);
return next_state(peer, input, cstatus,
STATE_OPEN_WAIT_FOR_OPEN_NOANCHOR);
}
break;
case STATE_OPEN_WAIT_FOR_OPEN_NOANCHOR:
if (input_is(input, PKT_OPEN)) {
err = accept_pkt_open(peer, idata->pkt);
if (err) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto err_breakdown;
}
return next_state(peer, input, cstatus, STATE_OPEN_WAIT_FOR_ANCHOR);
} else if (input_is(input, CMD_CLOSE)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto breakdown;
} else if (input_is_pkt(input)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAIT_FOR_OPEN_WITHANCHOR:
if (input_is(input, PKT_OPEN)) {
err = accept_pkt_open(peer, idata->pkt);
if (err) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto err_breakdown;
}
bitcoin_create_anchor(peer, BITCOIN_ANCHOR_CREATED);
return next_state(peer, input, cstatus,
STATE_OPEN_WAIT_FOR_ANCHOR_CREATE);
} else if (input_is(input, CMD_CLOSE)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto breakdown;
} else if (input_is_pkt(input)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAIT_FOR_ANCHOR_CREATE:
if (input_is(input, BITCOIN_ANCHOR_CREATED)) {
queue_pkt_anchor(peer);
return next_state(peer, input, cstatus,
STATE_OPEN_WAIT_FOR_COMMIT_SIG);
} else if (input_is(input, CMD_CLOSE)) {
bitcoin_release_anchor(peer, BITCOIN_ANCHOR_CREATED);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto breakdown;
} else if (input_is_pkt(input)) {
bitcoin_release_anchor(peer, BITCOIN_ANCHOR_CREATED);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAIT_FOR_ANCHOR:
if (input_is(input, PKT_OPEN_ANCHOR)) {
err = accept_pkt_anchor(peer, idata->pkt);
if (err) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto err_breakdown;
}
queue_pkt_open_commit_sig(peer);
peer_watch_anchor(peer,
BITCOIN_ANCHOR_DEPTHOK,
BITCOIN_ANCHOR_TIMEOUT);
return next_state(peer, input, cstatus,
STATE_OPEN_WAITING_THEIRANCHOR);
} else if (input_is(input, CMD_CLOSE)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto breakdown;
} else if (input_is_pkt(input)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAIT_FOR_COMMIT_SIG:
if (input_is(input, PKT_OPEN_COMMIT_SIG)) {
err = accept_pkt_open_commit_sig(peer, idata->pkt);
if (err) {
bitcoin_release_anchor(peer, INPUT_NONE);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto err_breakdown;
}
queue_tx_broadcast(broadcast, bitcoin_anchor(peer));
peer_watch_anchor(peer,
BITCOIN_ANCHOR_DEPTHOK,
INPUT_NONE);
return next_state(peer, input, cstatus,
STATE_OPEN_WAITING_OURANCHOR);
} else if (input_is(input, CMD_CLOSE)) {
bitcoin_release_anchor(peer, INPUT_NONE);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto breakdown;
} else if (input_is_pkt(input)) {
bitcoin_release_anchor(peer, INPUT_NONE);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAITING_OURANCHOR:
if (input_is(input, PKT_OPEN_COMPLETE)) {
err = accept_pkt_open_complete(peer, idata->pkt);
if (err) {
complete_cmd(peer, &cstatus, CMD_FAIL);
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
INPUT_NONE);
goto err_breakdown;
}
return next_state(peer, input, cstatus,
STATE_OPEN_WAITING_OURANCHOR_THEYCOMPLETED);
}
/* Fall thru */
case STATE_OPEN_WAITING_OURANCHOR_THEYCOMPLETED:
if (input_is(input, BITCOIN_ANCHOR_DEPTHOK)) {
queue_pkt_open_complete(peer);
if (peer->state == STATE_OPEN_WAITING_OURANCHOR_THEYCOMPLETED) {
complete_cmd(peer, &cstatus, CMD_SUCCESS);
return next_state(peer, input, cstatus, STATE_NORMAL);
}
return next_state(peer, input, cstatus,
STATE_OPEN_WAIT_FOR_COMPLETE_OURANCHOR);
} else if (input_is(input, CMD_CLOSE)) {
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
INPUT_NONE);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto start_clearing;
} else if (input_is(input, PKT_CLOSE_CLEARING)) {
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
INPUT_NONE);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto accept_clearing;
} else if (input_is_pkt(input)) {
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
INPUT_NONE);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAITING_THEIRANCHOR:
if (input_is(input, PKT_OPEN_COMPLETE)) {
err = accept_pkt_open_complete(peer, idata->pkt);
if (err) {
complete_cmd(peer, &cstatus, CMD_FAIL);
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
BITCOIN_ANCHOR_TIMEOUT);
goto err_breakdown;
}
return next_state(peer, input, cstatus,
STATE_OPEN_WAITING_THEIRANCHOR_THEYCOMPLETED);
}
/* Fall thru */
case STATE_OPEN_WAITING_THEIRANCHOR_THEYCOMPLETED:
if (input_is(input, BITCOIN_ANCHOR_TIMEOUT)) {
/* Anchor didn't reach blockchain in reasonable time. */
queue_pkt_err(peer, pkt_err(peer, "Anchor timed out"));
return next_state(peer, input, cstatus, STATE_ERR_ANCHOR_TIMEOUT);
} else if (input_is(input, BITCOIN_ANCHOR_DEPTHOK)) {
queue_pkt_open_complete(peer);
if (peer->state == STATE_OPEN_WAITING_THEIRANCHOR_THEYCOMPLETED) {
complete_cmd(peer, &cstatus, CMD_SUCCESS);
return next_state(peer, input, cstatus, STATE_NORMAL);
}
return next_state(peer, input, cstatus,
STATE_OPEN_WAIT_FOR_COMPLETE_THEIRANCHOR);
} else if (input_is(input, CMD_CLOSE)) {
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
BITCOIN_ANCHOR_TIMEOUT);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto start_clearing;
} else if (input_is(input, PKT_CLOSE_CLEARING)) {
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
BITCOIN_ANCHOR_TIMEOUT);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto accept_clearing;
} else if (input_is_pkt(input)) {
/* We no longer care about anchor depth. */
peer_unwatch_anchor_depth(peer,
BITCOIN_ANCHOR_DEPTHOK,
BITCOIN_ANCHOR_TIMEOUT);
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
case STATE_OPEN_WAIT_FOR_COMPLETE_OURANCHOR:
case STATE_OPEN_WAIT_FOR_COMPLETE_THEIRANCHOR:
if (input_is(input, PKT_OPEN_COMPLETE)) {
/* Ready for business! Anchorer goes first. */
if (peer->state == STATE_OPEN_WAIT_FOR_COMPLETE_OURANCHOR) {
complete_cmd(peer, &cstatus, CMD_SUCCESS);
return next_state(peer, input, cstatus, STATE_NORMAL);
} else {
complete_cmd(peer, &cstatus, CMD_SUCCESS);
return next_state(peer, input, cstatus, STATE_NORMAL);
}
} else if (input_is(input, CMD_CLOSE)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto start_clearing;
} else if (input_is(input, PKT_CLOSE_CLEARING)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto accept_clearing;
} else if (input_is_pkt(input)) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto unexpected_pkt;
}
break;
/*
* Channel normal operating states.
*/
case STATE_NORMAL:
/*
* FIXME: For simplicity, we disallow new staging requests
* while a commit is outstanding.
*/
/* You can only issue this command one at a time. */
if (input_is(input, CMD_SEND_COMMIT)) {
queue_pkt_commit(peer);
change_peer_cond(peer, PEER_CMD_OK, PEER_BUSY);
return next_state(peer, input, cstatus, STATE_NORMAL_COMMITTING);
} else if (input_is(input, CMD_SEND_HTLC_ADD)) {
/* We are to send an HTLC add. */
queue_pkt_htlc_add(peer, idata->htlc_prog);
return instant_cmd_success(peer, cstatus);
} else if (input_is(input, CMD_SEND_HTLC_FULFILL)) {
/* We are to send an HTLC fulfill. */
queue_pkt_htlc_fulfill(peer, idata->htlc_prog);
return instant_cmd_success(peer, cstatus);
} else if (input_is(input, CMD_SEND_HTLC_FAIL)) {
/* We are to send an HTLC fail. */
queue_pkt_htlc_fail(peer, idata->htlc_prog);
return instant_cmd_success(peer, cstatus);
}
/* Fall through... */
case STATE_NORMAL_COMMITTING:
/* Only expect revocation in STATE_NORMAL_COMMITTING */
if (peer->state == STATE_NORMAL_COMMITTING
&& input_is(input, PKT_UPDATE_REVOCATION)) {
err = accept_pkt_revocation(peer, idata->pkt);
if (err) {
complete_cmd(peer, &cstatus, CMD_FAIL);
goto err_breakdown;
}
complete_cmd(peer, &cstatus, CMD_SUCCESS);
return next_state(peer, input, cstatus, STATE_NORMAL);
}
if (input_is(input, CMD_CLOSE)) {
goto start_clearing;
} else if (input_is(input, PKT_UPDATE_ADD_HTLC)) {
err = accept_pkt_htlc_add(peer, idata->pkt);
if (err)
goto err_breakdown;
return unchanged_state(peer, input, cstatus);
} else if (input_is(input, PKT_UPDATE_FULFILL_HTLC)) {
err = accept_pkt_htlc_fulfill(peer, idata->pkt);
if (err)
goto err_breakdown;
return unchanged_state(peer, input, cstatus);
} else if (input_is(input, PKT_UPDATE_FAIL_HTLC)) {
err = accept_pkt_htlc_fail(peer, idata->pkt);
if (err)
goto err_breakdown;
return unchanged_state(peer, input, cstatus);
} else if (input_is(input, PKT_UPDATE_COMMIT)) {
err = accept_pkt_commit(peer, idata->pkt);
if (err)
goto err_breakdown;
queue_pkt_revocation(peer);
return unchanged_state(peer, input, cstatus);
} else if (input_is(input, PKT_CLOSE_CLEARING)) {
goto accept_clearing;
} else if (input_is_pkt(input)) {
goto unexpected_pkt;
}
break;
case STATE_US_CLEARING:
/* This is their reply once they're clearing too. */
if (input_is(input, PKT_CLOSE_CLEARING)) {
err = accept_pkt_close_clearing(peer, idata->pkt);
if (err)
goto err_breakdown;
/* Notify us when there are no more htlcs in
* either commit tx */
peer_watch_htlcs_cleared(peer, INPUT_HTLCS_CLEARED);
return next_state(peer, input, cstatus, STATE_BOTH_CLEARING);
/* FIXME: We must continue to allow fulfill & fail! */
} else if (input_is(input, CMD_SEND_HTLC_FAIL)
|| input_is(input, CMD_SEND_HTLC_FULFILL)) {
err = pkt_err(peer, "FIXME: cmd during clearing.");
goto err_breakdown;
} else if (input_is_pkt(input)) {
/* FIXME: We must continue to allow add, fulfill & fail packets */
goto unexpected_pkt;
}
break;
case STATE_BOTH_CLEARING:
if (input_is(input, INPUT_HTLCS_CLEARED)) {
goto start_closing_cleared;
} else if (input_is(input, CMD_SEND_HTLC_FAIL)
|| input_is(input, CMD_SEND_HTLC_FULFILL)) {
err = pkt_err(peer, "FIXME: cmd during clearing.");
goto err_breakdown;
} else if (input_is_pkt(input)) {
/* FIXME: We must continue to allow fulfill & fail packets */
goto unexpected_pkt;
}
break;
case STATE_WAIT_FOR_CLOSE_SIG:
if (input_is(input, PKT_CLOSE_SIGNATURE)) {
bool acked, we_agree;
err = accept_pkt_close_sig(peer, idata->pkt,
&acked, &we_agree);
if (err)
goto err_breakdown;
/* Are we about to offer the same fee they did? */
if (we_agree) {
/* Offer the new fee. */
queue_pkt_close_signature(peer);
acked = true;
}
/* Do fees now match? */
if (acked) {
/* Send close TX. */
queue_tx_broadcast(broadcast,
bitcoin_close(peer));
change_peer_cond(peer,
PEER_CLOSING, PEER_CLOSED);
return next_state(peer, input, cstatus,
STATE_CLOSE_WAIT_CLOSE);
}
/* Offer the new fee. */
queue_pkt_close_signature(peer);
return unchanged_state(peer, input, cstatus);
} else if (input_is(input, INPUT_CLOSE_COMPLETE_TIMEOUT)) {
err = pkt_err(peer, "Close timed out");
goto err_breakdown;
} else if (input_is_pkt(input)) {
goto unexpected_pkt;
}
break;
/* Should never happen. */
case STATE_ERR_INTERNAL:
case STATE_ERR_ANCHOR_TIMEOUT:
case STATE_ERR_INFORMATION_LEAK:
case STATE_ERR_BREAKDOWN:
case STATE_CLOSE_WAIT_CLOSE:
case STATE_CLOSED:
case STATE_MAX:
case STATE_CLOSE_ONCHAIN_CHEATED:
case STATE_CLOSE_ONCHAIN_THEIR_UNILATERAL:
case STATE_CLOSE_ONCHAIN_OUR_UNILATERAL:
case STATE_CLOSE_ONCHAIN_MUTUAL:
return next_state(peer, input, cstatus, STATE_ERR_INTERNAL);
}
/* State machine should handle all possible states. */
return next_state(peer, input, cstatus, STATE_ERR_INTERNAL);
unexpected_pkt:
peer_unexpected_pkt(peer, idata->pkt);
/* Don't reply to an error with an error. */
if (!input_is(input, PKT_ERROR)) {
goto breakdown;
}
err = pkt_err_unexpected(peer, idata->pkt);
err_breakdown:
queue_pkt_err(peer, err);
breakdown:
return next_state(peer, input, cstatus, STATE_ERR_BREAKDOWN);
start_clearing:
/*
* Start a mutual close: tell them we want to clear.
*/
queue_pkt_close_clearing(peer);
/* No more commands, we're already closing. */
set_peer_cond(peer, PEER_CLOSING);
return next_state(peer, input, cstatus, STATE_US_CLEARING);
start_closing_cleared:
/* As soon as we send packet, they could close. */
peer_calculate_close_fee(peer);
queue_pkt_close_signature(peer);
return next_state(peer, input, cstatus, STATE_WAIT_FOR_CLOSE_SIG);
accept_clearing:
err = accept_pkt_close_clearing(peer, idata->pkt);
if (err)
goto err_breakdown;
/* Notify us when there are no more htlcs in either commit tx */
peer_watch_htlcs_cleared(peer, INPUT_HTLCS_CLEARED);
/* No more commands, we're already closing. */
set_peer_cond(peer, PEER_CLOSING);
/* Tell them we're clearing too. */
queue_pkt_close_clearing(peer);
return next_state(peer, input, cstatus, STATE_BOTH_CLEARING);
}