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peer_htlcs.c
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#include <bitcoin/tx.h>
#include <ccan/build_assert/build_assert.h>
#include <ccan/crypto/ripemd160/ripemd160.h>
#include <ccan/mem/mem.h>
#include <ccan/tal/str/str.h>
#include <channeld/gen_channel_wire.h>
#include <common/json_escaped.h>
#include <common/overflows.h>
#include <common/sphinx.h>
#include <gossipd/gen_gossip_wire.h>
#include <lightningd/chaintopology.h>
#include <lightningd/htlc_end.h>
#include <lightningd/jsonrpc.h>
#include <lightningd/lightningd.h>
#include <lightningd/log.h>
#include <lightningd/pay.h>
#include <lightningd/peer_control.h>
#include <lightningd/peer_htlcs.h>
#include <lightningd/subd.h>
#include <onchaind/gen_onchain_wire.h>
#include <onchaind/onchain_wire.h>
#include <wallet/wallet.h>
#include <wire/gen_onion_wire.h>
static bool state_update_ok(struct channel *channel,
enum htlc_state oldstate, enum htlc_state newstate,
u64 htlc_id, const char *dir)
{
enum htlc_state expected = oldstate + 1;
/* We never get told about RCVD_REMOVE_HTLC, so skip over that
* (we initialize in SENT_ADD_HTLC / RCVD_ADD_COMMIT, so those
* work). */
if (expected == RCVD_REMOVE_HTLC)
expected = RCVD_REMOVE_COMMIT;
if (newstate != expected) {
channel_internal_error(channel,
"HTLC %s %"PRIu64" invalid update %s->%s",
dir, htlc_id,
htlc_state_name(oldstate),
htlc_state_name(newstate));
return false;
}
log_debug(channel->log, "HTLC %s %"PRIu64" %s->%s",
dir, htlc_id,
htlc_state_name(oldstate), htlc_state_name(newstate));
return true;
}
static bool htlc_in_update_state(struct channel *channel,
struct htlc_in *hin,
enum htlc_state newstate)
{
if (!state_update_ok(channel, hin->hstate, newstate, hin->key.id, "in"))
return false;
wallet_htlc_update(channel->peer->ld->wallet,
hin->dbid, newstate, hin->preimage);
hin->hstate = newstate;
htlc_in_check(hin, __func__);
return true;
}
static bool htlc_out_update_state(struct channel *channel,
struct htlc_out *hout,
enum htlc_state newstate)
{
if (!state_update_ok(channel, hout->hstate, newstate, hout->key.id,
"out"))
return false;
wallet_htlc_update(channel->peer->ld->wallet, hout->dbid, newstate,
NULL);
hout->hstate = newstate;
htlc_out_check(hout, __func__);
return true;
}
static void fail_in_htlc(struct htlc_in *hin,
enum onion_type failcode,
const u8 *failuremsg,
const struct short_channel_id *out_channelid)
{
assert(!hin->preimage);
assert(failcode || failuremsg);
hin->failcode = failcode;
if (failuremsg)
hin->failuremsg = tal_dup_arr(hin, u8, failuremsg, tal_len(failuremsg), 0);
/* We need this set, since we send it to channeld. */
if (hin->failcode & UPDATE)
hin->failoutchannel = *out_channelid;
else
memset(&hin->failoutchannel, 0, sizeof(hin->failoutchannel));
/* We update state now to signal it's in progress, for persistence. */
htlc_in_update_state(hin->key.channel, hin, SENT_REMOVE_HTLC);
/* Tell peer, if we can. */
if (!hin->key.channel->owner)
return;
/* onchaind doesn't care, it can't do anything but wait */
if (channel_on_chain(hin->key.channel))
return;
subd_send_msg(hin->key.channel->owner,
take(towire_channel_fail_htlc(hin,
hin->key.id,
hin->failuremsg,
hin->failcode,
&hin->failoutchannel)));
}
/* This is used for cases where we can immediately fail the HTLC. */
static void local_fail_htlc(struct htlc_in *hin, enum onion_type failcode,
const struct short_channel_id *out_channel)
{
log_info(hin->key.channel->log, "failed htlc %"PRIu64" code 0x%04x (%s)",
hin->key.id, failcode, onion_type_name(failcode));
fail_in_htlc(hin, failcode, NULL, out_channel);
}
/* localfail are for handing to the local payer if it's local. */
static void fail_out_htlc(struct htlc_out *hout, const char *localfail)
{
htlc_out_check(hout, __func__);
assert(hout->failcode || hout->failuremsg);
if (hout->in) {
fail_in_htlc(hout->in, hout->failcode, hout->failuremsg,
hout->key.channel->scid);
} else {
payment_failed(hout->key.channel->peer->ld, hout, localfail);
}
}
/* BOLT #4:
*
* * `amt_to_forward` - The amount in milli-satoshi to forward to the next
* (outgoing) hop specified within the routing information.
*
* This value MUST factor in the computed fee for this particular hop. When
* processing an incoming Sphinx packet along with the HTLC message it's
* encapsulated within, if the following inequality doesn't hold, then the
* HTLC should be rejected as it indicates a prior node in the path has
* deviated from the specified parameters:
*
* incoming_htlc_amt - fee >= amt_to_forward
*
* Where `fee` is calculated according to the receiving node's advertised fee
* schema as described in [BOLT 7](https://github.com/lightningnetwork/lightning-rfc/blob/master/07-routing-gossip.md#htlc-fees), or 0 if this node is the
* final hop.
*/
static bool check_amount(struct htlc_in *hin,
u64 amt_to_forward, u64 amt_in_htlc, u64 fee)
{
if (amt_in_htlc - fee >= amt_to_forward)
return true;
log_debug(hin->key.channel->log, "HTLC %"PRIu64" incorrect amount:"
" %"PRIu64" in, %"PRIu64" out, fee reqd %"PRIu64,
hin->key.id, amt_in_htlc, amt_to_forward, fee);
return false;
}
/* BOLT #4:
*
* * `outgoing_cltv_value` - The CLTV value that the _outgoing_ HTLC carrying
* the packet should have.
*
* cltv_expiry - cltv_expiry_delta >= outgoing_cltv_value
*
* Inclusion of this field allows a node to both authenticate the information
* specified by the original sender and the parameters of the HTLC forwarded,
* and ensure the original sender is using the current `cltv_expiry_delta` value.
* If there is no next hop, `cltv_expiry_delta` is zero.
* If the values don't correspond, then the HTLC should be failed+rejected as
* this indicates the incoming node has tampered with the intended HTLC
* values, or the origin has an obsolete `cltv_expiry_delta` value.
* The node MUST be consistent in responding to an unexpected
* `outgoing_cltv_value` whether it is the final hop or not, to avoid
* leaking that information.
*/
static bool check_cltv(struct htlc_in *hin,
u32 cltv_expiry, u32 outgoing_cltv_value, u32 delta)
{
if (cltv_expiry - delta >= outgoing_cltv_value)
return true;
log_debug(hin->key.channel->log, "HTLC %"PRIu64" incorrect CLTV:"
" %u in, %u out, delta reqd %u",
hin->key.id, cltv_expiry, outgoing_cltv_value, delta);
return false;
}
static void fulfill_htlc(struct htlc_in *hin, const struct preimage *preimage)
{
u8 *msg;
struct channel *channel = hin->key.channel;
struct wallet *wallet = channel->peer->ld->wallet;
hin->preimage = tal_dup(hin, struct preimage, preimage);
htlc_in_check(hin, __func__);
/* We update state now to signal it's in progress, for persistence. */
htlc_in_update_state(channel, hin, SENT_REMOVE_HTLC);
/* Update channel stats */
wallet_channel_stats_incr_in_fulfilled(wallet,
channel->dbid,
hin->msatoshi);
/* No owner? We'll either send to channeld in peer_htlcs, or
* onchaind in onchaind_tell_fulfill. */
if (!channel->owner) {
log_debug(channel->log, "HTLC fulfilled, but no owner.");
return;
}
if (channel_on_chain(channel)) {
msg = towire_onchain_known_preimage(hin, preimage);
} else {
msg = towire_channel_fulfill_htlc(hin, hin->key.id, preimage);
}
subd_send_msg(channel->owner, take(msg));
}
static void handle_localpay(struct htlc_in *hin,
u32 cltv_expiry,
const struct sha256 *payment_hash,
u64 amt_to_forward,
u32 outgoing_cltv_value)
{
enum onion_type failcode;
struct invoice invoice;
struct invoice_details details;
struct lightningd *ld = hin->key.channel->peer->ld;
/* BOLT #4:
*
* If the `amt_to_forward` is higher than `incoming_htlc_amt` of
* the HTLC at the final hop:
*
* 1. type: 19 (`final_incorrect_htlc_amount`)
* 2. data:
* * [`4`:`incoming_htlc_amt`]
*/
if (!check_amount(hin, amt_to_forward, hin->msatoshi, 0)) {
failcode = WIRE_FINAL_INCORRECT_HTLC_AMOUNT;
goto fail;
}
/* BOLT #4:
*
* If the `outgoing_cltv_value` does not match the `cltv_expiry` of
* the HTLC at the final hop:
*
* 1. type: 18 (`final_incorrect_cltv_expiry`)
* 2. data:
* * [`4`:`cltv_expiry`]
*/
if (!check_cltv(hin, cltv_expiry, outgoing_cltv_value, 0)) {
failcode = WIRE_FINAL_INCORRECT_CLTV_EXPIRY;
goto fail;
}
if (!wallet_invoice_find_unpaid(ld->wallet, &invoice, payment_hash)) {
failcode = WIRE_UNKNOWN_PAYMENT_HASH;
goto fail;
}
wallet_invoice_details(tmpctx, ld->wallet, invoice, &details);
/* BOLT #4:
*
* If the amount paid is less than the amount expected, the final node
* MUST fail the HTLC. If the amount paid is more than twice the
* amount expected, the final node SHOULD fail the HTLC. This allows
* the sender to reduce information leakage by altering the amount,
* without allowing accidental gross overpayment:
*
* 1. type: PERM|16 (`incorrect_payment_amount`)
*/
if (details.msatoshi != NULL && hin->msatoshi < *details.msatoshi) {
failcode = WIRE_INCORRECT_PAYMENT_AMOUNT;
goto fail;
} else if (details.msatoshi != NULL && hin->msatoshi > *details.msatoshi * 2) {
failcode = WIRE_INCORRECT_PAYMENT_AMOUNT;
goto fail;
}
/* BOLT #4:
*
* If the `cltv_expiry` is too low, the final node MUST fail the HTLC:
*/
if (get_block_height(ld->topology) + ld->config.cltv_final
> cltv_expiry) {
log_debug(hin->key.channel->log,
"Expiry cltv too soon %u < %u + %u",
cltv_expiry,
get_block_height(ld->topology),
ld->config.cltv_final);
failcode = WIRE_FINAL_EXPIRY_TOO_SOON;
goto fail;
}
log_info(ld->log, "Resolving invoice '%s' with HTLC %"PRIu64,
details.label->s, hin->key.id);
log_debug(ld->log, "%s: Actual amount %"PRIu64"msat, HTLC expiry %u",
details.label->s, hin->msatoshi, cltv_expiry);
fulfill_htlc(hin, &details.r);
wallet_invoice_resolve(ld->wallet, invoice, hin->msatoshi);
return;
fail:
/* Final hop never sends an UPDATE. */
assert(!(failcode & UPDATE));
local_fail_htlc(hin, failcode, NULL);
}
/*
* A catchall in case outgoing peer disconnects before getting fwd.
*
* We could queue this and wait for it to come back, but this is simple.
*/
static void destroy_hout_subd_died(struct htlc_out *hout)
{
log_debug(hout->key.channel->log,
"Failing HTLC %"PRIu64" due to peer death",
hout->key.id);
hout->failcode = WIRE_TEMPORARY_CHANNEL_FAILURE;
fail_out_htlc(hout, "Outgoing subdaemon died");
}
/* This is where channeld gives us the HTLC id, and also reports if it
* failed immediately. */
static void rcvd_htlc_reply(struct subd *subd, const u8 *msg, const int *fds UNUSED,
struct htlc_out *hout)
{
u16 failure_code;
u8 *failurestr;
struct lightningd *ld = subd->ld;
if (!fromwire_channel_offer_htlc_reply(msg, msg,
&hout->key.id,
&failure_code,
&failurestr)) {
channel_internal_error(subd->channel,
"Bad channel_offer_htlc_reply");
tal_free(hout);
return;
}
if (failure_code) {
hout->failcode = (enum onion_type) failure_code;
if (!hout->in) {
char *localfail = tal_fmt(msg, "%s: %.*s",
onion_type_name(failure_code),
(int)tal_len(failurestr),
(const char *)failurestr);
payment_failed(ld, hout, localfail);
} else
local_fail_htlc(hout->in, failure_code,
hout->key.channel->scid);
/* Prevent hout from being failed twice. */
tal_del_destructor(hout, destroy_hout_subd_died);
tal_free(hout);
return;
}
if (find_htlc_out(&subd->ld->htlcs_out, hout->key.channel, hout->key.id)
|| hout->key.id == HTLC_INVALID_ID) {
channel_internal_error(subd->channel,
"Bad offer_htlc_reply HTLC id %"PRIu64
" is a duplicate",
hout->key.id);
tal_free(hout);
return;
}
/* Add it to lookup table now we know id. */
connect_htlc_out(&subd->ld->htlcs_out, hout);
/* When channeld includes it in commitment, we'll make it persistent. */
}
enum onion_type send_htlc_out(struct channel *out, u64 amount, u32 cltv,
const struct sha256 *payment_hash,
const u8 *onion_routing_packet,
struct htlc_in *in,
struct htlc_out **houtp)
{
struct htlc_out *hout;
u8 *msg;
if (!channel_can_add_htlc(out)) {
log_info(out->log, "Attempt to send HTLC but not ready (%s)",
channel_state_name(out));
return WIRE_UNKNOWN_NEXT_PEER;
}
if (!out->owner) {
log_info(out->log, "Attempt to send HTLC but unowned (%s)",
channel_state_name(out));
return WIRE_TEMPORARY_CHANNEL_FAILURE;
}
/* Make peer's daemon own it, catch if it dies. */
hout = new_htlc_out(out->owner, out, amount, cltv,
payment_hash, onion_routing_packet, in);
tal_add_destructor(hout, destroy_hout_subd_died);
msg = towire_channel_offer_htlc(out, amount, cltv, payment_hash,
onion_routing_packet);
subd_req(out->peer->ld, out->owner, take(msg), -1, 0, rcvd_htlc_reply, hout);
if (houtp)
*houtp = hout;
return 0;
}
static void forward_htlc(struct htlc_in *hin,
u32 cltv_expiry,
u64 amt_to_forward,
u32 outgoing_cltv_value,
const struct pubkey *next_hop,
const u8 next_onion[TOTAL_PACKET_SIZE])
{
enum onion_type failcode;
u64 fee;
struct lightningd *ld = hin->key.channel->peer->ld;
struct channel *next = active_channel_by_id(ld, next_hop, NULL);
/* Unknown peer, or peer not ready. */
if (!next || !next->scid) {
local_fail_htlc(hin, WIRE_UNKNOWN_NEXT_PEER, NULL);
return;
}
/* BOLT #7:
*
* The node creating `channel_update` SHOULD accept HTLCs which pay a
* fee equal or greater than:
*
* fee_base_msat + amount_msat * fee_proportional_millionths / 1000000
*/
if (mul_overflows_u64(amt_to_forward,
ld->config.fee_per_satoshi)) {
failcode = WIRE_FEE_INSUFFICIENT;
goto fail;
}
fee = ld->config.fee_base
+ amt_to_forward * ld->config.fee_per_satoshi / 1000000;
if (!check_amount(hin, amt_to_forward, hin->msatoshi, fee)) {
failcode = WIRE_FEE_INSUFFICIENT;
goto fail;
}
if (!check_cltv(hin, cltv_expiry, outgoing_cltv_value,
ld->config.cltv_expiry_delta)) {
failcode = WIRE_INCORRECT_CLTV_EXPIRY;
goto fail;
}
/* BOLT #2:
*
* A node MUST estimate a timeout deadline for each HTLC it offers. A
* node MUST NOT offer an HTLC with a timeout deadline before its
* `cltv_expiry`
*/
/* In our case, G = 1, so we need to expire it one after it's expiration.
* But never offer an expired HTLC; that's dumb. */
if (get_block_height(ld->topology) >= outgoing_cltv_value) {
log_debug(hin->key.channel->log,
"Expiry cltv %u too close to current %u",
outgoing_cltv_value,
get_block_height(ld->topology));
failcode = WIRE_EXPIRY_TOO_SOON;
goto fail;
}
/* BOLT #4:
*
* If the `cltv_expiry` is unreasonably far, we can also report an error:
*
* 1. type: 21 (`expiry_too_far`)
*/
if (get_block_height(ld->topology)
+ ld->config.locktime_max < outgoing_cltv_value) {
log_debug(hin->key.channel->log,
"Expiry cltv %u too far from current %u + max %u",
outgoing_cltv_value,
get_block_height(ld->topology),
ld->config.locktime_max);
failcode = WIRE_EXPIRY_TOO_FAR;
goto fail;
}
failcode = send_htlc_out(next, amt_to_forward,
outgoing_cltv_value, &hin->payment_hash,
next_onion, hin, NULL);
if (!failcode)
return;
fail:
local_fail_htlc(hin, failcode, next->scid);
}
/* Temporary information, while we resolve the next hop */
struct gossip_resolve {
struct short_channel_id next_channel;
u64 amt_to_forward;
u32 outgoing_cltv_value;
u8 *next_onion;
struct htlc_in *hin;
};
/* We received a resolver reply, which gives us the node_ids of the
* channel we want to forward over */
static void channel_resolve_reply(struct subd *gossip, const u8 *msg,
const int *fds UNUSED, struct gossip_resolve *gr)
{
struct pubkey *nodes, *peer_id;
if (!fromwire_gossip_resolve_channel_reply(msg, msg, &nodes)) {
log_broken(gossip->log,
"bad fromwire_gossip_resolve_channel_reply %s",
tal_hex(msg, msg));
return;
}
if (tal_count(nodes) == 0) {
local_fail_htlc(gr->hin, WIRE_UNKNOWN_NEXT_PEER, NULL);
return;
} else if (tal_count(nodes) != 2) {
log_broken(gossip->log,
"fromwire_gossip_resolve_channel_reply has %zu nodes",
tal_count(nodes));
return;
}
/* Get the other peer matching the id that is not us */
if (pubkey_cmp(&nodes[0], &gossip->ld->id) == 0) {
peer_id = &nodes[1];
} else {
peer_id = &nodes[0];
}
forward_htlc(gr->hin, gr->hin->cltv_expiry,
gr->amt_to_forward, gr->outgoing_cltv_value, peer_id,
gr->next_onion);
tal_free(gr);
}
/* Everyone is committed to this htlc of theirs */
static bool peer_accepted_htlc(struct channel *channel,
u64 id,
enum onion_type *failcode)
{
struct htlc_in *hin;
u8 *req;
struct route_step *rs;
struct onionpacket *op;
struct lightningd *ld = channel->peer->ld;
hin = find_htlc_in(&ld->htlcs_in, channel, id);
if (!hin) {
channel_internal_error(channel,
"peer_got_revoke unknown htlc %"PRIu64, id);
return false;
}
if (!htlc_in_update_state(channel, hin, RCVD_ADD_ACK_REVOCATION))
return false;
#if DEVELOPER
if (channel->peer->ignore_htlcs) {
log_debug(channel->log, "their htlc %"PRIu64" dev_ignore_htlcs",
id);
return true;
}
#endif
/* BOLT #2:
*
* A sending node SHOULD fail to route any HTLC added after it
* sent `shutdown`. */
if (channel->state == CHANNELD_SHUTTING_DOWN) {
*failcode = WIRE_PERMANENT_CHANNEL_FAILURE;
goto out;
}
/* BOLT #2:
*
* A node MUST estimate a fulfillment deadline for each HTLC it is
* attempting to fulfill. A node MUST fail (and not forward) an HTLC
* whose fulfillment deadline is already past
*/
/* Our deadline is half the cltv_delta we insist on, so this check is
* a subset of the cltv check done in handle_localpay and
* forward_htlc. */
/* channeld tests this, so it should have set ss to zeroes. */
op = parse_onionpacket(tmpctx, hin->onion_routing_packet,
sizeof(hin->onion_routing_packet));
if (!op) {
if (!memeqzero(&hin->shared_secret, sizeof(hin->shared_secret))){
channel_internal_error(channel,
"bad onion in got_revoke: %s",
tal_hexstr(channel, hin->onion_routing_packet,
sizeof(hin->onion_routing_packet)));
return false;
}
/* FIXME: could be bad version, bad key. */
*failcode = WIRE_INVALID_ONION_VERSION;
goto out;
}
/* Channeld sets this to zero if HSM won't ecdh it */
if (memeqzero(&hin->shared_secret, sizeof(hin->shared_secret))) {
*failcode = WIRE_INVALID_ONION_KEY;
goto out;
}
/* If it's crap, not channeld's fault, just fail it */
rs = process_onionpacket(tmpctx, op, hin->shared_secret.data,
hin->payment_hash.u.u8,
sizeof(hin->payment_hash));
if (!rs) {
*failcode = WIRE_INVALID_ONION_HMAC;
goto out;
}
/* Unknown realm isn't a bad onion, it's a normal failure. */
if (rs->hop_data.realm != 0) {
*failcode = WIRE_INVALID_REALM;
goto out;
}
if (rs->nextcase == ONION_FORWARD) {
struct gossip_resolve *gr = tal(ld, struct gossip_resolve);
gr->next_onion = serialize_onionpacket(gr, rs->next);
gr->next_channel = rs->hop_data.channel_id;
gr->amt_to_forward = rs->hop_data.amt_forward;
gr->outgoing_cltv_value = rs->hop_data.outgoing_cltv;
gr->hin = hin;
req = towire_gossip_resolve_channel_request(tmpctx,
&gr->next_channel);
log_debug(channel->log, "Asking gossip to resolve channel %s",
type_to_string(tmpctx, struct short_channel_id,
&gr->next_channel));
subd_req(hin, ld->gossip, req, -1, 0,
channel_resolve_reply, gr);
} else
handle_localpay(hin, hin->cltv_expiry, &hin->payment_hash,
rs->hop_data.amt_forward,
rs->hop_data.outgoing_cltv);
*failcode = 0;
out:
log_debug(channel->log, "their htlc %"PRIu64" %s",
id, *failcode ? onion_type_name(*failcode) : "locked");
return true;
}
static void fulfill_our_htlc_out(struct channel *channel, struct htlc_out *hout,
const struct preimage *preimage)
{
struct lightningd *ld = channel->peer->ld;
assert(!hout->preimage);
hout->preimage = tal_dup(hout, struct preimage, preimage);
htlc_out_check(hout, __func__);
wallet_htlc_update(ld->wallet, hout->dbid, hout->hstate, preimage);
/* Update channel stats */
wallet_channel_stats_incr_out_fulfilled(ld->wallet,
channel->dbid,
hout->msatoshi);
if (hout->in)
fulfill_htlc(hout->in, preimage);
else
payment_succeeded(ld, hout, preimage);
}
static bool peer_fulfilled_our_htlc(struct channel *channel,
const struct fulfilled_htlc *fulfilled)
{
struct lightningd *ld = channel->peer->ld;
struct htlc_out *hout;
hout = find_htlc_out(&ld->htlcs_out, channel, fulfilled->id);
if (!hout) {
channel_internal_error(channel,
"fulfilled_our_htlc unknown htlc %"PRIu64,
fulfilled->id);
return false;
}
if (!htlc_out_update_state(channel, hout, RCVD_REMOVE_COMMIT))
return false;
fulfill_our_htlc_out(channel, hout, &fulfilled->payment_preimage);
return true;
}
void onchain_fulfilled_htlc(struct channel *channel,
const struct preimage *preimage)
{
struct htlc_out_map_iter outi;
struct htlc_out *hout;
struct sha256 payment_hash;
struct lightningd *ld = channel->peer->ld;
sha256(&payment_hash, preimage, sizeof(*preimage));
/* FIXME: use db to look this up! */
for (hout = htlc_out_map_first(&ld->htlcs_out, &outi);
hout;
hout = htlc_out_map_next(&ld->htlcs_out, &outi)) {
if (hout->key.channel != channel)
continue;
/* It's possible that we failed some and succeeded one,
* if we got multiple errors. */
if (hout->failcode != 0 || hout->failuremsg)
continue;
if (!structeq(&hout->payment_hash, &payment_hash))
continue;
/* We may have already fulfilled before going onchain, or
* we can fulfill onchain multiple times. */
if (!hout->preimage)
fulfill_our_htlc_out(channel, hout, preimage);
/* We keep going: this is something of a leak, but onchain
* we have no real way of distinguishing HTLCs anyway */
}
}
static bool peer_failed_our_htlc(struct channel *channel,
const struct failed_htlc *failed)
{
struct htlc_out *hout;
struct lightningd *ld = channel->peer->ld;
hout = find_htlc_out(&ld->htlcs_out, channel, failed->id);
if (!hout) {
channel_internal_error(channel,
"failed_our_htlc unknown htlc %"PRIu64,
failed->id);
return false;
}
if (!htlc_out_update_state(channel, hout, RCVD_REMOVE_COMMIT))
return false;
hout->failcode = failed->malformed;
if (!failed->malformed)
hout->failuremsg = tal_dup_arr(hout, u8, failed->failreason,
tal_len(failed->failreason), 0);
else
hout->failuremsg = NULL;
log_debug(channel->log, "Our HTLC %"PRIu64" failed (%u)", failed->id,
hout->failcode);
htlc_out_check(hout, __func__);
return true;
}
/* FIXME: Crazy slow! */
struct htlc_out *find_htlc_out_by_ripemd(const struct channel *channel,
const struct ripemd160 *ripemd)
{
struct htlc_out_map_iter outi;
struct htlc_out *hout;
struct lightningd *ld = channel->peer->ld;
for (hout = htlc_out_map_first(&ld->htlcs_out, &outi);
hout;
hout = htlc_out_map_next(&ld->htlcs_out, &outi)) {
struct ripemd160 hash;
if (hout->key.channel != channel)
continue;
ripemd160(&hash,
&hout->payment_hash, sizeof(hout->payment_hash));
if (structeq(&hash, ripemd))
return hout;
}
return NULL;
}
void onchain_failed_our_htlc(const struct channel *channel,
const struct htlc_stub *htlc,
const char *why)
{
struct lightningd *ld = channel->peer->ld;
struct htlc_out *hout = find_htlc_out_by_ripemd(channel, &htlc->ripemd);
/* Don't fail twice! */
if (hout->failuremsg || hout->failcode)
return;
hout->failcode = WIRE_PERMANENT_CHANNEL_FAILURE;
if (!hout->in) {
assert(why != NULL);
char *localfail = tal_fmt(channel, "%s: %s",
onion_type_name(WIRE_PERMANENT_CHANNEL_FAILURE),
why);
payment_failed(ld, hout, localfail);
tal_free(localfail);
} else
local_fail_htlc(hout->in, WIRE_PERMANENT_CHANNEL_FAILURE,
hout->key.channel->scid);
}
static void remove_htlc_in(struct channel *channel, struct htlc_in *hin)
{
htlc_in_check(hin, __func__);
assert(hin->failuremsg || hin->preimage || hin->failcode);
log_debug(channel->log, "Removing in HTLC %"PRIu64" state %s %s",
hin->key.id, htlc_state_name(hin->hstate),
hin->preimage ? "FULFILLED"
: hin->failcode ? onion_type_name(hin->failcode)
: "REMOTEFAIL");
/* If we fulfilled their HTLC, credit us. */
if (hin->preimage) {
log_debug(channel->log, "Balance %"PRIu64" -> %"PRIu64,
channel->our_msatoshi,
channel->our_msatoshi + hin->msatoshi);
channel->our_msatoshi += hin->msatoshi;
if (channel->our_msatoshi > channel->msatoshi_to_us_max)
channel->msatoshi_to_us_max = channel->our_msatoshi;
}
tal_free(hin);
}
static void remove_htlc_out(struct channel *channel, struct htlc_out *hout)
{
htlc_out_check(hout, __func__);
assert(hout->failuremsg || hout->preimage || hout->failcode);
log_debug(channel->log, "Removing out HTLC %"PRIu64" state %s %s",
hout->key.id, htlc_state_name(hout->hstate),
hout->preimage ? "FULFILLED"
: hout->failcode ? onion_type_name(hout->failcode)
: "REMOTEFAIL");
/* If it's failed, now we can forward since it's completely locked-in */
if (!hout->preimage) {
fail_out_htlc(hout, NULL);
} else {
/* We paid for this HTLC, so deduct balance. */
log_debug(channel->log, "Balance %"PRIu64" -> %"PRIu64,
channel->our_msatoshi,
channel->our_msatoshi - hout->msatoshi);
channel->our_msatoshi -= hout->msatoshi;
if (channel->our_msatoshi < channel->msatoshi_to_us_min)
channel->msatoshi_to_us_min = channel->our_msatoshi;
}
tal_free(hout);
}
static bool update_in_htlc(struct channel *channel,
u64 id, enum htlc_state newstate)
{
struct htlc_in *hin;
struct lightningd *ld = channel->peer->ld;
hin = find_htlc_in(&ld->htlcs_in, channel, id);
if (!hin) {
channel_internal_error(channel, "Can't find in HTLC %"PRIu64, id);
return false;
}
if (!htlc_in_update_state(channel, hin, newstate))
return false;
if (newstate == SENT_REMOVE_ACK_REVOCATION)
remove_htlc_in(channel, hin);
return true;
}
static bool update_out_htlc(struct channel *channel,
u64 id, enum htlc_state newstate)
{
struct lightningd *ld = channel->peer->ld;
struct htlc_out *hout;
hout = find_htlc_out(&ld->htlcs_out, channel, id);
if (!hout) {
channel_internal_error(channel, "Can't find out HTLC %"PRIu64, id);
return false;
}
if (!hout->dbid) {
wallet_htlc_save_out(ld->wallet, channel, hout);
/* Update channel stats */
wallet_channel_stats_incr_out_offered(ld->wallet,
channel->dbid,
hout->msatoshi);
/* For our own HTLCs, we commit payment to db lazily */
if (hout->origin_htlc_id == 0)
payment_store(ld,
&hout->payment_hash);
}
if (!htlc_out_update_state(channel, hout, newstate))
return false;
/* First transition into commitment; now it outlives peer. */
if (newstate == SENT_ADD_COMMIT) {
tal_del_destructor(hout, destroy_hout_subd_died);
tal_steal(ld, hout);
} else if (newstate == RCVD_REMOVE_ACK_REVOCATION) {
remove_htlc_out(channel, hout);
}
return true;
}
static bool changed_htlc(struct channel *channel,
const struct changed_htlc *changed)
{
if (htlc_state_owner(changed->newstate) == LOCAL)
return update_out_htlc(channel, changed->id, changed->newstate);
else
return update_in_htlc(channel, changed->id, changed->newstate);
}
static bool peer_save_commitsig_received(struct channel *channel, u64 commitnum,
struct bitcoin_tx *tx,
const secp256k1_ecdsa_signature *commit_sig)
{
if (commitnum != channel->next_index[LOCAL]) {
channel_internal_error(channel,
"channel_got_commitsig: expected commitnum %"PRIu64
" got %"PRIu64,
channel->next_index[LOCAL], commitnum);
return false;
}
channel->next_index[LOCAL]++;
/* Update channel->last_sig and channel->last_tx before saving to db */
channel_set_last_tx(channel, tx, commit_sig);
return true;
}
static bool peer_save_commitsig_sent(struct channel *channel, u64 commitnum)
{
struct lightningd *ld = channel->peer->ld;
if (commitnum != channel->next_index[REMOTE]) {
channel_internal_error(channel,
"channel_sent_commitsig: expected commitnum %"PRIu64
" got %"PRIu64,
channel->next_index[REMOTE], commitnum);
return false;
}
channel->next_index[REMOTE]++;
/* FIXME: Save to database, with sig and HTLCs. */
wallet_channel_save(ld->wallet, channel);
return true;
}
void peer_sending_commitsig(struct channel *channel, const u8 *msg)
{
u64 commitnum;
u32 feerate;
struct changed_htlc *changed_htlcs;
size_t i, maxid = 0, num_local_added = 0;
secp256k1_ecdsa_signature commit_sig;
secp256k1_ecdsa_signature *htlc_sigs;
struct lightningd *ld = channel->peer->ld;
if (!fromwire_channel_sending_commitsig(msg, msg,
&commitnum,
&feerate,
&changed_htlcs,