/
invoice.c
1978 lines (1741 loc) · 60.5 KB
/
invoice.c
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#include "config.h"
#include <ccan/array_size/array_size.h>
#include <ccan/asort/asort.h>
#include <ccan/cast/cast.h>
#include <ccan/json_escape/json_escape.h>
#include <ccan/str/hex/hex.h>
#include <ccan/tal/str/str.h>
#include <common/blindedpath.h>
#include <common/bolt11_json.h>
#include <common/bolt12_merkle.h>
#include <common/configdir.h>
#include <common/invoice_path_id.h>
#include <common/json_command.h>
#include <common/json_param.h>
#include <common/overflows.h>
#include <common/random_select.h>
#include <common/timeout.h>
#include <common/type_to_string.h>
#include <db/exec.h>
#include <errno.h>
#include <hsmd/hsmd_wiregen.h>
#include <lightningd/channel.h>
#include <lightningd/hsm_control.h>
#include <lightningd/invoice.h>
#include <lightningd/notification.h>
#include <lightningd/plugin_hook.h>
#include <lightningd/routehint.h>
#include <sodium/randombytes.h>
#include <wallet/invoices.h>
#include <wire/wire_sync.h>
const char *invoice_status_str(enum invoice_status state)
{
switch (state) {
case PAID:
return "paid";
case EXPIRED:
return "expired";
case UNPAID:
return "unpaid";
}
abort();
}
static void json_add_invoice_fields(struct json_stream *response,
const struct invoice_details *inv)
{
json_add_escaped_string(response, "label", inv->label);
if (inv->invstring)
json_add_invstring(response, inv->invstring);
json_add_sha256(response, "payment_hash", &inv->rhash);
if (inv->msat)
json_add_amount_msat(response, "amount_msat", *inv->msat);
json_add_string(response, "status", invoice_status_str(inv->state));
if (inv->state == PAID) {
json_add_u64(response, "pay_index", inv->pay_index);
json_add_amount_msat(response,
"amount_received_msat", inv->received);
json_add_u64(response, "paid_at", inv->paid_timestamp);
json_add_preimage(response, "payment_preimage", &inv->r);
}
if (inv->description)
json_add_string(response, "description", inv->description);
json_add_u64(response, "expires_at", inv->expiry_time);
if (inv->local_offer_id) {
char *fail;
struct tlv_invoice *tinv;
json_add_sha256(response, "local_offer_id", inv->local_offer_id);
/* Everyone loves seeing their own payer notes!
* Well: they will. Trust me. */
tinv = invoice_decode(tmpctx,
inv->invstring, strlen(inv->invstring),
NULL, NULL, &fail);
if (tinv && tinv->invreq_payer_note)
json_add_stringn(response, "invreq_payer_note",
tinv->invreq_payer_note,
tal_bytelen(tinv->invreq_payer_note));
}
json_add_u64(response, "created_index", inv->created_index);
if (inv->updated_index)
json_add_u64(response, "updated_index", inv->updated_index);
}
static void json_add_invoice(struct json_stream *response,
const char *fieldname,
const struct invoice_details *inv)
{
json_object_start(response, fieldname);
json_add_invoice_fields(response, inv);
json_object_end(response);
}
static struct command_result *tell_waiter(struct command *cmd, u64 inv_dbid)
{
struct json_stream *response;
const struct invoice_details *details;
details = invoices_get_details(cmd, cmd->ld->wallet->invoices, inv_dbid);
if (details->state == PAID) {
response = json_stream_success(cmd);
json_add_invoice_fields(response, details);
return command_success(cmd, response);
} else {
response = json_stream_fail(cmd, INVOICE_EXPIRED_DURING_WAIT,
"invoice expired during wait");
json_add_invoice_fields(response, details);
json_object_end(response);
return command_failed(cmd, response);
}
}
static void tell_waiter_deleted(struct command *cmd)
{
was_pending(command_fail(cmd, LIGHTNINGD,
"Invoice deleted during wait"));
}
static void wait_on_invoice(const u64 *inv_dbid, void *cmd)
{
if (inv_dbid)
tell_waiter((struct command *) cmd, *inv_dbid);
else
tell_waiter_deleted((struct command *) cmd);
}
static void wait_timed_out(struct command *cmd)
{
was_pending(command_fail(cmd, INVOICE_WAIT_TIMED_OUT,
"Timed out while waiting "
"for invoice to be paid"));
}
/* We derive invoice secret using 1-way function from payment_preimage
* (just a different one from the payment_hash!) */
static void invoice_secret(const struct preimage *payment_preimage,
struct secret *payment_secret)
{
struct preimage modified;
struct sha256 secret;
modified = *payment_preimage;
modified.r[0] ^= 1;
sha256(&secret, modified.r,
ARRAY_SIZE(modified.r) * sizeof(*modified.r));
BUILD_ASSERT(sizeof(secret.u.u8) == sizeof(payment_secret->data));
memcpy(payment_secret->data, secret.u.u8, sizeof(secret.u.u8));
}
/* FIXME: The spec should require a *real* secret: a signature of the
* payment_hash using the payer_id key. This just means they've
* *seen* the invoice! */
static void invoice_secret_bolt12(struct lightningd *ld,
const struct sha256 *payment_hash,
struct secret *payment_secret)
{
const void *path_id = invoice_path_id(tmpctx,
&ld->invoicesecret_base,
payment_hash);
assert(tal_bytelen(path_id) == sizeof(*payment_secret));
memcpy(payment_secret, path_id, sizeof(*payment_secret));
}
struct invoice_payment_hook_payload {
struct lightningd *ld;
/* Set to NULL if it is deleted while waiting for plugin */
struct htlc_set *set;
/* What invoice it's trying to pay. */
const struct json_escape *label;
/* Amount it's offering. */
struct amount_msat msat;
/* Preimage we'll give it if succeeds. */
struct preimage preimage;
/* FIXME: Include raw payload! */
};
#ifdef DEVELOPER
static void invoice_payment_add_tlvs(struct json_stream *stream,
struct htlc_set *hset)
{
struct htlc_in *hin;
const struct tlv_payload *tlvs;
assert(tal_count(hset->htlcs) > 0);
/* Pick the first HTLC as representative for the entire set. */
hin = hset->htlcs[0];
tlvs = hin->payload->tlv;
json_array_start(stream, "extratlvs");
for (size_t i = 0; i < tal_count(tlvs->fields); i++) {
struct tlv_field *field = &tlvs->fields[i];
/* If we have metadata attached it is not an extra TLV field. */
if (field->meta == NULL) {
json_object_start(stream, NULL);
json_add_u64(stream, "type", field->numtype);
json_add_num(stream, "length", field->length);
json_add_hex_talarr(stream, "value", field->value);
json_object_end(stream);
}
}
json_array_end(stream);
}
#endif
static void
invoice_payment_serialize(struct invoice_payment_hook_payload *payload,
struct json_stream *stream,
struct plugin *plugin)
{
json_object_start(stream, "payment");
json_add_escaped_string(stream, "label", payload->label);
json_add_preimage(stream, "preimage", &payload->preimage);
json_add_string(stream, "msat",
type_to_string(tmpctx, struct amount_msat,
&payload->msat));
#ifdef DEVELOPER
invoice_payment_add_tlvs(stream, payload->set);
#endif
json_object_end(stream); /* .payment */
}
/* Set times out or HTLC deleted? Remove set ptr from payload so we
* know to ignore plugin return */
static void invoice_payload_remove_set(struct htlc_set *set,
struct invoice_payment_hook_payload *payload)
{
assert(payload->set == set);
payload->set = NULL;
}
static const u8 *hook_gives_failmsg(const tal_t *ctx,
struct lightningd *ld,
const struct htlc_in *hin,
const char *buffer,
const jsmntok_t *toks)
{
const jsmntok_t *resulttok;
const jsmntok_t *t;
unsigned int val;
/* No plugin registered on hook at all? */
if (!buffer)
return NULL;
resulttok = json_get_member(buffer, toks, "result");
if (resulttok) {
if (json_tok_streq(buffer, resulttok, "continue")) {
return NULL;
} else if (json_tok_streq(buffer, resulttok, "reject")) {
return failmsg_incorrect_or_unknown(ctx, ld, hin);
} else
fatal("Invalid invoice_payment hook result: %.*s",
toks[0].end - toks[0].start, buffer);
}
t = json_get_member(buffer, toks, "failure_message");
if (t) {
const u8 *failmsg = json_tok_bin_from_hex(ctx, buffer, t);
if (!failmsg)
fatal("Invalid invoice_payment_hook failure_message: %.*s",
toks[0].end - toks[1].start, buffer);
return failmsg;
}
if (!ld->deprecated_apis)
return NULL;
t = json_get_member(buffer, toks, "failure_code");
if (!t) {
static bool warned = false;
if (!warned) {
warned = true;
log_unusual(ld->log,
"Plugin did not return object with "
"'result' or 'failure_message' fields. "
"This is now deprecated and you should "
"return {'result': 'continue' } or "
"{'result': 'reject'} or "
"{'failure_message'... instead.");
}
return failmsg_incorrect_or_unknown(ctx, ld, hin);
}
if (!json_to_number(buffer, t, &val))
fatal("Invalid invoice_payment_hook failure_code: %.*s",
toks[0].end - toks[1].start, buffer);
if (val == WIRE_TEMPORARY_NODE_FAILURE)
return towire_temporary_node_failure(ctx);
if (val != WIRE_INCORRECT_OR_UNKNOWN_PAYMENT_DETAILS)
log_broken(hin->key.channel->log,
"invoice_payment hook returned failcode %u,"
" changing to incorrect_or_unknown_payment_details",
val);
return failmsg_incorrect_or_unknown(ctx, ld, hin);
}
static void
invoice_payment_hooks_done(struct invoice_payment_hook_payload *payload STEALS)
{
u64 inv_dbid;
struct lightningd *ld = payload->ld;
tal_del_destructor2(payload->set, invoice_payload_remove_set, payload);
/* We want to free this, whatever happens. */
tal_steal(tmpctx, payload);
/* If invoice gets paid meanwhile (plugin responds out-of-order?) then
* we can also fail */
if (!invoices_find_by_label(ld->wallet->invoices, &inv_dbid, payload->label)) {
htlc_set_fail(payload->set, take(failmsg_incorrect_or_unknown(
NULL, ld, payload->set->htlcs[0])));
return;
}
/* Paid or expired in the meantime. */
if (!invoices_resolve(ld->wallet->invoices, inv_dbid, payload->msat,
payload->label)) {
htlc_set_fail(payload->set, take(failmsg_incorrect_or_unknown(
NULL, ld, payload->set->htlcs[0])));
return;
}
log_info(ld->log, "Resolved invoice '%s' with amount %s in %zu htlcs",
payload->label->s,
type_to_string(tmpctx, struct amount_msat, &payload->msat),
tal_count(payload->set->htlcs));
htlc_set_fulfill(payload->set, &payload->preimage);
notify_invoice_payment(ld, payload->msat, payload->preimage,
payload->label);
}
static bool
invoice_payment_deserialize(struct invoice_payment_hook_payload *payload,
const char *buffer,
const jsmntok_t *toks)
{
struct lightningd *ld = payload->ld;
const u8 *failmsg;
/* If peer dies or something, this can happen. */
if (!payload->set) {
log_debug(ld->log, "invoice '%s' paying htlc_in has gone!",
payload->label->s);
return false;
}
/* Did we have a hook result? */
failmsg = hook_gives_failmsg(NULL, ld,
payload->set->htlcs[0], buffer, toks);
if (failmsg) {
htlc_set_fail(payload->set, take(failmsg));
return false;
}
return true;
}
REGISTER_PLUGIN_HOOK(invoice_payment,
invoice_payment_deserialize,
invoice_payment_hooks_done,
invoice_payment_serialize,
struct invoice_payment_hook_payload *);
const struct invoice_details *
invoice_check_payment(const tal_t *ctx,
struct lightningd *ld,
const struct sha256 *payment_hash,
const struct amount_msat msat,
const struct secret *payment_secret,
const char **err)
{
u64 inv_dbid;
const struct invoice_details *details;
/* BOLT #4:
* - if the payment hash has already been paid:
* - MAY treat the payment hash as unknown.
* - MAY succeed in accepting the HTLC.
*...
* - if the payment hash is unknown:
* - MUST fail the HTLC.
* - MUST return an `incorrect_or_unknown_payment_details` error.
*/
if (!invoices_find_unpaid(ld->wallet->invoices, &inv_dbid, payment_hash)) {
if (invoices_find_by_rhash(ld->wallet->invoices, &inv_dbid, payment_hash)) {
*err = tal_fmt(ctx, "Already paid or expired invoice %s",
type_to_string(tmpctx, struct sha256, payment_hash));
} else {
*err = tal_fmt(ctx, "Unknown invoice %s",
type_to_string(tmpctx, struct sha256, payment_hash));
}
return NULL;
}
details = invoices_get_details(ctx, ld->wallet->invoices, inv_dbid);
/* BOLT #4:
* - if the `payment_secret` doesn't match the expected value for that
* `payment_hash`, or the `payment_secret` is required and is not
* present:
* - MUST fail the HTLC.
*/
if (feature_is_set(details->features, COMPULSORY_FEATURE(OPT_VAR_ONION))
&& !payment_secret) {
*err = tal_fmt(ctx, "Attempt to pay %s without secret",
type_to_string(tmpctx, struct sha256, &details->rhash));
return tal_free(details);
}
if (payment_secret) {
struct secret expected;
if (details->invstring && strstarts(details->invstring, "lni1"))
invoice_secret_bolt12(ld, payment_hash, &expected);
else
invoice_secret(&details->r, &expected);
if (!secret_eq_consttime(payment_secret, &expected)) {
*err = tal_fmt(ctx, "Attempt to pay %s with wrong secret",
type_to_string(tmpctx, struct sha256,
&details->rhash));
return tal_free(details);
}
}
/* BOLT #4:
*
* An _intermediate hop_ MUST NOT, but the _final node_:
*...
* - if the amount paid is less than the amount expected:
* - MUST fail the HTLC.
*/
if (details->msat != NULL) {
struct amount_msat twice;
if (amount_msat_less(msat, *details->msat)) {
*err = tal_fmt(ctx, "Attempt to pay %s with amount %s < %s",
type_to_string(tmpctx, struct sha256,
&details->rhash),
type_to_string(tmpctx, struct amount_msat, &msat),
type_to_string(tmpctx, struct amount_msat, details->msat));
return tal_free(details);
}
if (amount_msat_add(&twice, *details->msat, *details->msat)
&& amount_msat_greater(msat, twice)) {
*err = tal_fmt(ctx, "Attempt to pay %s with amount %s > %s",
type_to_string(tmpctx, struct sha256,
&details->rhash),
type_to_string(tmpctx, struct amount_msat, &msat),
type_to_string(tmpctx, struct amount_msat, &twice));
/* BOLT #4:
*
* - if the amount paid is more than twice the amount
* expected:
* - SHOULD fail the HTLC.
*/
return tal_free(details);
}
}
return details;
}
void invoice_try_pay(struct lightningd *ld,
struct htlc_set *set,
const struct invoice_details *details)
{
struct invoice_payment_hook_payload *payload;
payload = tal(NULL, struct invoice_payment_hook_payload);
payload->ld = ld;
payload->label = tal_steal(payload, details->label);
payload->msat = set->so_far;
payload->preimage = details->r;
payload->set = set;
tal_add_destructor2(set, invoice_payload_remove_set, payload);
plugin_hook_call_invoice_payment(ld, NULL, payload);
}
static bool hsm_sign_b11(const u5 *u5bytes,
const u8 *hrpu8,
secp256k1_ecdsa_recoverable_signature *rsig,
struct lightningd *ld)
{
const u8 *msg;
msg = hsm_sync_req(tmpctx, ld,
take(towire_hsmd_sign_invoice(NULL, u5bytes, hrpu8)));
if (!fromwire_hsmd_sign_invoice_reply(msg, rsig))
fatal("HSM gave bad sign_invoice_reply %s",
tal_hex(msg, msg));
return true;
}
static void hsm_sign_b12_invoice(struct lightningd *ld,
struct tlv_invoice *invoice)
{
struct sha256 merkle;
const u8 *msg;
assert(!invoice->signature);
merkle_tlv(invoice->fields, &merkle);
msg = towire_hsmd_sign_bolt12(NULL, "invoice", "signature", &merkle, NULL);
msg = hsm_sync_req(tmpctx, ld, take(msg));
invoice->signature = tal(invoice, struct bip340sig);
if (!fromwire_hsmd_sign_bolt12_reply(msg, invoice->signature))
fatal("HSM gave bad sign_invoice_reply %s",
tal_hex(msg, msg));
}
static struct command_result *parse_fallback(struct command *cmd,
const char *buffer,
const jsmntok_t *fallback,
const u8 **fallback_script)
{
enum address_parse_result fallback_parse;
fallback_parse
= json_to_address_scriptpubkey(cmd,
chainparams,
buffer, fallback,
fallback_script);
if (fallback_parse == ADDRESS_PARSE_UNRECOGNIZED) {
return command_fail(cmd, LIGHTNINGD,
"Fallback address not valid");
} else if (fallback_parse == ADDRESS_PARSE_WRONG_NETWORK) {
return command_fail(cmd, LIGHTNINGD,
"Fallback address does not match our network %s",
chainparams->network_name);
}
return NULL;
}
/*
* From array of incoming channels [inchan], find suitable ones for
* a payment-to-us of [amount_needed], using criteria:
* 1. Channel's peer is known, in state CHANNELD_NORMAL and is online.
* 2. Channel's peer capacity to pay us is sufficient.
*
* Then use weighted reservoir sampling, which makes probing channel balances
* harder, to choose one channel from the set of suitable channels. It favors
* channels that have less balance on our side as fraction of their capacity.
*/
static struct route_info **select_inchan(const tal_t *ctx,
struct lightningd *ld,
struct amount_msat amount_needed,
const struct routehint_candidate
*candidates)
{
/* BOLT11 struct wants an array of arrays (can provide multiple routes) */
struct route_info **r = NULL;
double total_weight = 0.0;
/* Collect suitable channels and assign each a weight. */
for (size_t i = 0; i < tal_count(candidates); i++) {
struct amount_msat excess, capacity;
struct amount_sat cumulative_reserve;
double excess_frac;
/* Does the peer have sufficient balance to pay us,
* even after having taken into account their reserve? */
if (!amount_msat_sub(&excess, candidates[i].capacity,
amount_needed))
continue;
/* Channel balance as seen by our node:
|<----------------- capacity ----------------->|
. .
. |<------------------ their_msat -------------------->|
. | . |
. |<----- capacity_to_pay_us ----->|<- their_reserve ->|
. | | |
. |<- amount_needed --><- excess ->| |
. | | |
|-------|-------------|--------------------------------|-------------------|
0 ^ ^ ^ funding
our_reserve our_msat */
/* Find capacity and calculate its excess fraction */
if (!amount_sat_add(&cumulative_reserve,
candidates[i].c->our_config.channel_reserve,
candidates[i].c->channel_info.their_config.channel_reserve)
|| !amount_sat_to_msat(&capacity, candidates[i].c->funding_sats)
|| !amount_msat_sub_sat(&capacity, capacity, cumulative_reserve)) {
log_broken(ld->log, "Channel %s capacity overflow!",
type_to_string(tmpctx, struct short_channel_id, candidates[i].c->scid));
continue;
}
/* We don't want a 0 probability if 0 excess; it might be the
* only one! So bump it by 1 msat */
if (!amount_msat_add(&excess, excess, AMOUNT_MSAT(1))) {
log_broken(ld->log, "Channel %s excess overflow!",
type_to_string(tmpctx,
struct short_channel_id,
candidates[i].c->scid));
continue;
}
excess_frac = amount_msat_ratio(excess, capacity);
if (random_select(excess_frac, &total_weight)) {
tal_free(r);
r = tal_arr(ctx, struct route_info *, 1);
r[0] = tal_dup(r, struct route_info, candidates[i].r);
}
}
return r;
}
static int cmp_rr_number(const struct routehint_candidate *a,
const struct routehint_candidate *b,
struct lightningd *ld)
{
if (a->c->rr_number > b->c->rr_number)
return 1;
if (a->c->rr_number < b->c->rr_number)
return -1;
/* They're unique, so can't be equal */
log_broken(ld->log, "Two equal candidates %p and %p, channels %p and %p, rr_number %"PRIu64" and %"PRIu64,
a, b, a->c, b->c, a->c->rr_number, b->c->rr_number);
return 0;
}
/** select_inchan_mpp
*
* @brief fallback in case select_inchan cannot find a *single*
* channel capable of accepting the payment as a whole.
* Also the main routehint-selector if we are completely unpublished
* (i.e. all our channels are unpublished), since if we are completely
* unpublished then the payer cannot fall back to just directly routing
* to us.
*/
static struct route_info **select_inchan_mpp(const tal_t *ctx,
struct lightningd *ld,
struct amount_msat amount_needed,
struct routehint_candidate
*candidates)
{
/* The total amount we have gathered for incoming channels. */
struct amount_msat gathered;
/* Routehint array. */
struct route_info **routehints;
gathered = AMOUNT_MSAT(0);
routehints = tal_arr(ctx, struct route_info *, 0);
/* Sort by rr_number, so we get fresh channels. */
asort(candidates, tal_count(candidates), cmp_rr_number, ld);
for (size_t i = 0; i < tal_count(candidates); i++) {
if (amount_msat_greater_eq(gathered, amount_needed))
break;
/* Add to current routehints set. */
if (!amount_msat_add(&gathered, gathered, candidates[i].capacity)) {
log_broken(ld->log,
"Gathered channel capacity overflow: "
"%s + %s",
type_to_string(tmpctx, struct amount_msat, &gathered),
type_to_string(tmpctx, struct amount_msat,
&candidates[i].capacity));
continue;
}
tal_arr_expand(&routehints,
tal_dup(routehints, struct route_info,
candidates[i].r));
/* Put to the back of the round-robin list */
candidates[i].c->rr_number = ld->rr_counter++;
}
return routehints;
}
/* Encapsulating struct while we wait for gossipd to give us incoming channels */
struct chanhints {
bool expose_all_private;
struct short_channel_id *hints;
};
struct invoice_info {
struct command *cmd;
struct preimage payment_preimage;
struct bolt11 *b11;
struct json_escape *label;
struct chanhints *chanhints;
};
/* Add routehints based on listincoming results: NULL means success. */
static struct command_result *
add_routehints(struct invoice_info *info,
const char *buffer,
const jsmntok_t *toks,
bool *warning_mpp,
bool *warning_capacity,
bool *warning_deadends,
bool *warning_offline,
bool *warning_private_unused)
{
const struct chanhints *chanhints = info->chanhints;
bool node_unpublished;
struct amount_msat avail_capacity, deadend_capacity, offline_capacity,
private_capacity;
struct routehint_candidate *candidates;
struct amount_msat total, needed;
/* Dev code can force routes. */
if (info->b11->routes) {
*warning_mpp = *warning_capacity = *warning_deadends
= *warning_offline = *warning_private_unused
= false;
return NULL;
}
candidates = routehint_candidates(tmpctx, info->cmd->ld,
buffer, toks,
chanhints ? &chanhints->expose_all_private : NULL,
chanhints ? chanhints->hints : NULL,
&node_unpublished,
&avail_capacity,
&private_capacity,
&deadend_capacity,
&offline_capacity);
/* If they told us to use scids and we couldn't, fail. */
if (tal_count(candidates) == 0
&& chanhints && tal_count(chanhints->hints) != 0) {
return command_fail(info->cmd,
INVOICE_HINTS_GAVE_NO_ROUTES,
"None of those hints were suitable local channels");
}
needed = info->b11->msat ? *info->b11->msat : AMOUNT_MSAT(1);
/* If we are not completely unpublished, try with reservoir
* sampling first.
*
* Why do we not do this if we are completely unpublished?
* Because it is possible that multiple invoices will, by
* chance, select the same channel as routehint.
* This single channel might not be able to accept all the
* incoming payments on all the invoices generated.
* If we were published, that is fine because the payer can
* fall back to just attempting to route directly.
* But if we were unpublished, the only way for the payer to
* reach us would be via the routehints we provide, so we
* should make an effort to avoid overlapping incoming
* channels, which is done by select_inchan_mpp.
*/
if (!node_unpublished)
info->b11->routes = select_inchan(info->b11,
info->cmd->ld,
needed,
candidates);
/* If we are completely unpublished, or if the above reservoir
* sampling fails, select channels by round-robin. */
if (tal_count(info->b11->routes) == 0) {
info->b11->routes = select_inchan_mpp(info->b11,
info->cmd->ld,
needed,
candidates);
*warning_mpp = (tal_count(info->b11->routes) > 1);
} else {
*warning_mpp = false;
}
log_debug(info->cmd->ld->log, "needed = %s, avail_capacity = %s, private_capacity = %s, offline_capacity = %s, deadend_capacity = %s",
type_to_string(tmpctx, struct amount_msat, &needed),
type_to_string(tmpctx, struct amount_msat, &avail_capacity),
type_to_string(tmpctx, struct amount_msat, &private_capacity),
type_to_string(tmpctx, struct amount_msat, &offline_capacity),
type_to_string(tmpctx, struct amount_msat, &deadend_capacity));
if (!amount_msat_add(&total, avail_capacity, offline_capacity)
|| !amount_msat_add(&total, total, deadend_capacity)
|| !amount_msat_add(&total, total, private_capacity))
fatal("Cannot add %s + %s + %s + %s",
type_to_string(tmpctx, struct amount_msat,
&avail_capacity),
type_to_string(tmpctx, struct amount_msat,
&offline_capacity),
type_to_string(tmpctx, struct amount_msat,
&deadend_capacity),
type_to_string(tmpctx, struct amount_msat,
&private_capacity));
/* If we literally didn't have capacity at all, warn. */
*warning_capacity = amount_msat_greater_eq(needed, total);
/* We only warn about these if we didn't have capacity and
* they would have helped. */
*warning_offline = false;
*warning_deadends = false;
*warning_private_unused = false;
if (amount_msat_greater(needed, avail_capacity)) {
struct amount_msat tot;
/* We didn't get enough: would offline have helped? */
if (!amount_msat_add(&tot, avail_capacity, offline_capacity))
abort();
if (amount_msat_greater_eq(tot, needed)) {
*warning_offline = true;
goto done;
}
/* Hmm, what about deadends? */
if (!amount_msat_add(&tot, tot, deadend_capacity))
abort();
if (amount_msat_greater_eq(tot, needed)) {
*warning_deadends = true;
goto done;
}
/* What about private channels? */
if (!amount_msat_add(&tot, tot, private_capacity))
abort();
if (amount_msat_greater_eq(tot, needed)) {
*warning_private_unused = true;
goto done;
}
}
done:
return NULL;
}
static struct command_result *
invoice_complete(struct invoice_info *info,
bool warning_no_listincoming,
bool warning_mpp,
bool warning_capacity,
bool warning_deadends,
bool warning_offline,
bool warning_private_unused)
{
struct json_stream *response;
u64 inv_dbid;
char *b11enc;
const struct invoice_details *details;
struct secret payment_secret;
struct wallet *wallet = info->cmd->ld->wallet;
b11enc = bolt11_encode(info, info->b11, false,
hsm_sign_b11, info->cmd->ld);
/* Check duplicate preimage (unlikely unless they specified it!) */
if (invoices_find_by_rhash(wallet->invoices,
&inv_dbid, &info->b11->payment_hash)) {
return command_fail(info->cmd,
INVOICE_PREIMAGE_ALREADY_EXISTS,
"preimage already used");
}
if (!invoices_create(wallet->invoices,
&inv_dbid,
info->b11->msat,
info->label,
info->b11->expiry,
b11enc,
info->b11->description,
info->b11->features,
&info->payment_preimage,
&info->b11->payment_hash,
NULL)) {
return command_fail(info->cmd, INVOICE_LABEL_ALREADY_EXISTS,
"Duplicate label '%s'",
info->label->s);
}
/* Get details */
details = invoices_get_details(info, wallet->invoices, inv_dbid);
response = json_stream_success(info->cmd);
json_add_sha256(response, "payment_hash", &details->rhash);
json_add_u64(response, "expires_at", details->expiry_time);
json_add_string(response, "bolt11", details->invstring);
invoice_secret(&details->r, &payment_secret);
json_add_secret(response, "payment_secret", &payment_secret);
json_add_u64(response, "created_index", details->created_index);
notify_invoice_creation(info->cmd->ld, info->b11->msat,
info->payment_preimage, info->label);
if (warning_no_listincoming)
json_add_string(response, "warning_listincoming",
"No listincoming command available, cannot add routehints to invoice");
if (warning_mpp)
json_add_string(response, "warning_mpp",
"The invoice is only payable by MPP-capable payers.");
if (warning_capacity)
json_add_string(response, "warning_capacity",
"Insufficient incoming channel capacity to pay invoice");
if (warning_deadends)
json_add_string(response, "warning_deadends",
"Insufficient incoming capacity, once dead-end peers were excluded");
if (warning_offline)
json_add_string(response, "warning_offline",
"Insufficient incoming capacity, once offline peers were excluded");
if (warning_private_unused)
json_add_string(response, "warning_private_unused",
"Insufficient incoming capacity, once private channels were excluded (try exposeprivatechannels=true?)");
return command_success(info->cmd, response);
}
/* Return from "listincoming". */
static void listincoming_done(const char *buffer,
const jsmntok_t *toks,
const jsmntok_t *idtok UNUSED,
struct invoice_info *info)
{
struct lightningd *ld = info->cmd->ld;
struct command_result *ret;
bool warning_mpp, warning_capacity, warning_deadends, warning_offline, warning_private_unused;
ret = add_routehints(info, buffer, toks,
&warning_mpp,
&warning_capacity,
&warning_deadends,
&warning_offline,
&warning_private_unused);
if (ret)
return;
/* We're actually outside a db transaction here: spooky! */
db_begin_transaction(ld->wallet->db);
invoice_complete(info,
false,
warning_mpp,
warning_capacity,
warning_deadends,
warning_offline,
warning_private_unused);
db_commit_transaction(ld->wallet->db);
}
#if DEVELOPER
/* Since this is a dev-only option, we will crash if dev-routes is not
* an array-of-arrays-of-correct-items. */
static struct route_info *unpack_route(const tal_t *ctx,
const char *buffer,
const jsmntok_t *routetok)
{
const jsmntok_t *t;
size_t i;
struct route_info *route = tal_arr(ctx, struct route_info, routetok->size);
json_for_each_arr(i, t, routetok) {
const jsmntok_t *pubkey, *fee_base, *fee_prop, *scid, *cltv;
struct route_info *r = &route[i];
u32 cltv_u32;
pubkey = json_get_member(buffer, t, "id");
scid = json_get_member(buffer, t, "short_channel_id");
fee_base = json_get_member(buffer, t, "fee_base_msat");
fee_prop = json_get_member(buffer, t,
"fee_proportional_millionths");
cltv = json_get_member(buffer, t, "cltv_expiry_delta");
if (!json_to_node_id(buffer, pubkey, &r->pubkey)
|| !json_to_short_channel_id(buffer, scid,
&r->short_channel_id)
|| !json_to_number(buffer, fee_base, &r->fee_base_msat)
|| !json_to_number(buffer, fee_prop,
&r->fee_proportional_millionths)
|| !json_to_number(buffer, cltv, &cltv_u32))
abort();
/* We don't have a json_to_u16 */
r->cltv_expiry_delta = cltv_u32;
}
return route;
}
static struct route_info **unpack_routes(const tal_t *ctx,
const char *buffer,
const jsmntok_t *routestok)
{
struct route_info **routes;
const jsmntok_t *t;
size_t i;
if (!routestok)
return NULL;
routes = tal_arr(ctx, struct route_info *, routestok->size);
json_for_each_arr(i, t, routestok)