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#include "bitcoin/block.h"
#include "bitcoin/tx.h"
#include "bitcoind.h"
#include "chaintopology.h"
#include "jsonrpc.h"
#include "lightningd.h"
#include "log.h"
#include "peer.h"
#include "timeout.h"
#include "utils.h"
#include "watch.h"
#include <ccan/array_size/array_size.h>
#include <ccan/asort/asort.h>
#include <ccan/io/io.h>
#include <ccan/structeq/structeq.h>
#include <ccan/tal/str/str.h>
#include <inttypes.h>
struct block {
int height;
/* Actual header. */
struct bitcoin_block_hdr hdr;
/* Previous block (if any). */
struct block *prev;
/* Next block (if any). */
struct block *next;
/* Key for hash table */
struct sha256_double blkid;
/* 0 if not enough predecessors. */
u32 mediantime;
/* Transactions in this block we care about */
struct sha256_double *txids;
/* And their associated index in the block */
u32 *txnums;
/* Full copy of txs (trimmed to txs list in connect_block) */
struct bitcoin_tx **full_txs;
};
/* Hash blocks by sha */
static const struct sha256_double *keyof_block_map(const struct block *b)
{
return &b->blkid;
}
static size_t hash_sha(const struct sha256_double *key)
{
size_t ret;
memcpy(&ret, key, sizeof(ret));
return ret;
}
static bool block_eq(const struct block *b, const struct sha256_double *key)
{
return structeq(&b->blkid, key);
}
HTABLE_DEFINE_TYPE(struct block, keyof_block_map, hash_sha, block_eq, block_map);
struct topology {
struct block *root;
struct block *tip;
struct block_map block_map;
u64 feerate;
bool startup;
};
static void start_poll_chaintip(struct lightningd_state *dstate);
static void next_topology_timer(struct lightningd_state *dstate)
{
if (dstate->topology->startup) {
dstate->topology->startup = false;
io_break(dstate);
}
new_reltimer(dstate, dstate, dstate->config.poll_time,
start_poll_chaintip, dstate);
}
static int cmp_times(const u32 *a, const u32 *b, void *unused)
{
if (*a > *b)
return -1;
else if (*b > * a)
return 1;
return 0;
}
/* Mediantime is median of this and previous 10 blocks. */
static u32 get_mediantime(const struct topology *topo, const struct block *b)
{
unsigned int i;
u32 times[11];
for (i = 0; i < ARRAY_SIZE(times); i++) {
if (!b)
return 0;
times[i] = le32_to_cpu(b->hdr.timestamp);
b = b->prev;
}
asort(times, ARRAY_SIZE(times), cmp_times, NULL);
return times[ARRAY_SIZE(times) / 2];
}
/* FIXME: Remove tx from block when peer done. */
static void add_tx_to_block(struct block *b, const struct sha256_double *txid, const u32 txnum)
{
size_t n = tal_count(b->txids);
tal_resize(&b->txids, n+1);
tal_resize(&b->txnums, n+1);
b->txids[n] = *txid;
b->txnums[n] = txnum;
}
static bool we_broadcast(struct lightningd_state *dstate,
const struct sha256_double *txid)
{
struct peer *peer;
list_for_each(&dstate->peers, peer, list) {
struct outgoing_tx *otx;
list_for_each(&peer->outgoing_txs, otx, list) {
if (structeq(&otx->txid, txid))
return true;
}
}
return false;
}
/* Fills in prev, height, mediantime. */
static void connect_block(struct lightningd_state *dstate,
struct block *prev,
struct block *b)
{
struct topology *topo = dstate->topology;
size_t i;
assert(b->height == -1);
assert(b->mediantime == 0);
assert(b->prev == NULL);
assert(prev->next == b);
b->prev = prev;
b->height = b->prev->height + 1;
b->mediantime = get_mediantime(topo, b);
block_map_add(&topo->block_map, b);
/* Now we see if any of those txs are interesting. */
for (i = 0; i < tal_count(b->full_txs); i++) {
struct bitcoin_tx *tx = b->full_txs[i];
struct sha256_double txid;
size_t j;
/* Tell them if it spends a txo we care about. */
for (j = 0; j < tx->input_count; j++) {
struct txwatch_output out;
struct txowatch *txo;
out.txid = tx->input[j].txid;
out.index = tx->input[j].index;
txo = txowatch_hash_get(&dstate->txowatches, &out);
if (txo)
txowatch_fire(dstate, txo, tx, j);
}
/* We did spends first, in case that tells us to watch tx. */
bitcoin_txid(tx, &txid);
if (watching_txid(dstate, &txid) || we_broadcast(dstate, &txid))
add_tx_to_block(b, &txid, i);
}
b->full_txs = tal_free(b->full_txs);
/* Tell peers about new block. */
peers_new_block(dstate, b->height);
}
static bool tx_in_block(const struct block *b,
const struct sha256_double *txid)
{
size_t i, n = tal_count(b->txids);
for (i = 0; i < n; i++) {
if (structeq(&b->txids[i], txid))
return true;
}
return false;
}
/* FIXME: Use hash table. */
static struct block *block_for_tx(struct lightningd_state *dstate,
const struct sha256_double *txid)
{
struct topology *topo = dstate->topology;
struct block *b;
for (b = topo->tip; b; b = b->prev) {
if (tx_in_block(b, txid))
return b;
}
return NULL;
}
size_t get_tx_depth(struct lightningd_state *dstate,
const struct sha256_double *txid)
{
struct topology *topo = dstate->topology;
const struct block *b;
b = block_for_tx(dstate, txid);
if (!b)
return 0;
return topo->tip->height - b->height + 1;
}
struct txs_to_broadcast {
/* We just sent txs[cursor] */
size_t cursor;
/* These are hex encoded already, for bitcoind_sendrawtx */
const char **txs;
/* Command to complete when we're done, iff dev-broadcast triggered */
struct command *cmd;
};
/* We just sent the last entry in txs[]. Shrink and send the next last. */
static void broadcast_remainder(struct lightningd_state *dstate,
int exitstatus, const char *msg,
struct txs_to_broadcast *txs)
{
/* These are expected. */
if (strstr(msg, "txn-mempool-conflict")
|| strstr(msg, "transaction already in block chain"))
log_debug(dstate->base_log,
"Expected error broadcasting tx %s: %s",
txs->txs[txs->cursor], msg);
else if (exitstatus)
log_unusual(dstate->base_log, "Broadcasting tx %s: %i %s",
txs->txs[txs->cursor], exitstatus, msg);
txs->cursor++;
if (txs->cursor == tal_count(txs->txs)) {
if (txs->cmd)
command_success(txs->cmd, null_response(txs->cmd));
tal_free(txs);
return;
}
/* Broadcast next one. */
bitcoind_sendrawtx(NULL, dstate, txs->txs[txs->cursor],
broadcast_remainder, txs);
}
/* FIXME: This is dumb. We can group txs and avoid bothering bitcoind
* if any one tx is in the main chain. */
static void rebroadcast_txs(struct lightningd_state *dstate,
struct command *cmd)
{
/* Copy txs now (peers may go away, and they own txs). */
size_t num_txs = 0;
struct txs_to_broadcast *txs;
struct peer *peer;
if (dstate->dev_no_broadcast)
return;
txs = tal(dstate, struct txs_to_broadcast);
txs->cmd = cmd;
/* Put any txs we want to broadcast in ->txs. */
txs->txs = tal_arr(txs, const char *, 0);
list_for_each(&dstate->peers, peer, list) {
struct outgoing_tx *otx;
list_for_each(&peer->outgoing_txs, otx, list) {
if (block_for_tx(dstate, &otx->txid))
continue;
tal_resize(&txs->txs, num_txs+1);
txs->txs[num_txs] = tal_strdup(txs, otx->hextx);
num_txs++;
}
}
/* Let this do the dirty work. */
txs->cursor = (size_t)-1;
broadcast_remainder(dstate, 0, "", txs);
}
static void destroy_outgoing_tx(struct outgoing_tx *otx)
{
list_del_from(&otx->peer->outgoing_txs, &otx->list);
}
static void broadcast_done(struct lightningd_state *dstate,
int exitstatus, const char *msg,
struct outgoing_tx *otx)
{
if (otx->failed && exitstatus != 0) {
otx->failed(otx->peer, exitstatus, msg);
tal_free(otx);
} else {
/* For continual rebroadcasting */
list_add_tail(&otx->peer->outgoing_txs, &otx->list);
tal_add_destructor(otx, destroy_outgoing_tx);
}
}
void broadcast_tx(struct peer *peer, const struct bitcoin_tx *tx,
void (*failed)(struct peer *peer,
int exitstatus, const char *err))
{
struct outgoing_tx *otx = tal(peer, struct outgoing_tx);
const u8 *rawtx = linearize_tx(otx, tx);
otx->peer = peer;
bitcoin_txid(tx, &otx->txid);
otx->hextx = tal_hex(otx, rawtx);
otx->failed = failed;
tal_free(rawtx);
log_add_struct(peer->log, " (tx %s)", struct sha256_double, &otx->txid);
if (peer->dstate->dev_no_broadcast)
broadcast_done(peer->dstate, 0, "dev_no_broadcast", otx);
else
bitcoind_sendrawtx(peer, peer->dstate, otx->hextx,
broadcast_done, otx);
}
static void free_blocks(struct lightningd_state *dstate, struct block *b)
{
struct block *next;
while (b) {
size_t i, n = tal_count(b->txids);
/* Notify that txs are kicked out. */
for (i = 0; i < n; i++)
txwatch_fire(dstate, &b->txids[i], 0);
next = b->next;
tal_free(b);
b = next;
}
}
static void update_fee(struct lightningd_state *dstate, u64 rate, u64 *feerate)
{
log_debug(dstate->base_log, "Feerate %"PRIu64" -> %"PRIu64,
rate, *feerate);
*feerate = rate;
}
/* B is the new chain (linked by ->next); update topology */
static void topology_changed(struct lightningd_state *dstate,
struct block *prev,
struct block *b)
{
/* Eliminate any old chain. */
if (prev->next)
free_blocks(dstate, prev->next);
prev->next = b;
do {
connect_block(dstate, prev, b);
dstate->topology->tip = prev = b;
b = b->next;
} while (b);
/* Tell watch code to re-evaluate all txs. */
watch_topology_changed(dstate);
/* Maybe need to rebroadcast. */
rebroadcast_txs(dstate, NULL);
/* Once per new block head, update fee estimate. */
bitcoind_estimate_fee(dstate, update_fee, &dstate->topology->feerate);
}
static struct block *new_block(struct lightningd_state *dstate,
struct bitcoin_block *blk,
struct block *next)
{
struct topology *topo = dstate->topology;
struct block *b = tal(topo, struct block);
sha256_double(&b->blkid, &blk->hdr, sizeof(blk->hdr));
log_debug_struct(dstate->base_log, "Adding block %s",
struct sha256_double, &b->blkid);
assert(!block_map_get(&topo->block_map, &b->blkid));
b->next = next;
/* We fill these out in topology_changed */
b->height = -1;
b->mediantime = 0;
b->prev = NULL;
b->hdr = blk->hdr;
b->txids = tal_arr(b, struct sha256_double, 0);
b->txnums = tal_arr(b, u32, 0);
b->full_txs = tal_steal(b, blk->tx);
return b;
}
static void gather_blocks(struct lightningd_state *dstate,
struct bitcoin_block *blk,
struct block *next)
{
struct topology *topo = dstate->topology;
struct block *b, *prev;
b = new_block(dstate, blk, next);
/* Recurse if we need prev. */
prev = block_map_get(&topo->block_map, &blk->hdr.prev_hash);
if (!prev) {
bitcoind_getrawblock(dstate, &blk->hdr.prev_hash,
gather_blocks, b);
return;
}
/* All done. */
topology_changed(dstate, prev, b);
next_topology_timer(dstate);
}
static void check_chaintip(struct lightningd_state *dstate,
const struct sha256_double *tipid,
void *arg)
{
struct topology *topo = dstate->topology;
/* 0 is the main tip. */
if (!structeq(tipid, &topo->tip->blkid))
bitcoind_getrawblock(dstate, tipid, gather_blocks,
(struct block *)NULL);
else
/* Next! */
next_topology_timer(dstate);
}
static void start_poll_chaintip(struct lightningd_state *dstate)
{
if (!list_empty(&dstate->bitcoin_req)) {
log_unusual(dstate->base_log,
"Delaying start poll: commands in progress");
next_topology_timer(dstate);
} else
bitcoind_get_chaintip(dstate, check_chaintip, NULL);
}
static void init_topo(struct lightningd_state *dstate,
struct bitcoin_block *blk,
ptrint_t *p)
{
struct topology *topo = dstate->topology;
topo->root = new_block(dstate, blk, NULL);
topo->root->height = ptr2int(p);
block_map_add(&topo->block_map, topo->root);
topo->tip = topo->root;
/* Now grab chaintip immediately. */
bitcoind_get_chaintip(dstate, check_chaintip, NULL);
}
static void get_init_block(struct lightningd_state *dstate,
const struct sha256_double *blkid,
ptrint_t *blknum)
{
bitcoind_getrawblock(dstate, blkid, init_topo, blknum);
}
static void get_init_blockhash(struct lightningd_state *dstate, u32 blockcount,
void *unused)
{
u32 start;
struct peer *peer;
/* Start back before any reasonable forks. */
if (blockcount < dstate->config.forever_confirms)
start = 0;
else
start = blockcount - dstate->config.forever_confirms;
/* If loaded from database, go back to earliest possible peer anchor. */
list_for_each(&dstate->peers, peer, list) {
if (peer->anchor.min_depth && peer->anchor.min_depth < start)
start = peer->anchor.min_depth;
}
/* Start topology from 100 blocks back. */
bitcoind_getblockhash(dstate, start, get_init_block, int2ptr(start));
}
u32 get_tx_mediantime(struct lightningd_state *dstate,
const struct sha256_double *txid)
{
struct block *b;
b = block_for_tx(dstate, txid);
if (b)
return b->mediantime;
fatal("Tx %s not found for get_tx_mediantime",
tal_hexstr(dstate, txid, sizeof(*txid)));
}
u32 get_tip_mediantime(struct lightningd_state *dstate)
{
return dstate->topology->tip->mediantime;
}
u32 get_block_height(struct lightningd_state *dstate)
{
return dstate->topology->tip->height;
}
u64 get_feerate(struct lightningd_state *dstate)
{
if (dstate->config.override_fee_rate) {
log_debug(dstate->base_log,
"Forcing fee rate, ignoring estimate");
return dstate->config.override_fee_rate;
}
else if (dstate->topology->feerate == 0) {
log_info(dstate->base_log,
"No fee estimate: using default fee rate");
return dstate->config.default_fee_rate;
}
return dstate->topology->feerate;
}
struct txlocator *locate_tx(const void *ctx, struct lightningd_state *dstate,
const struct sha256_double *txid)
{
struct block *block = block_for_tx(dstate, txid);
if (block == NULL) {
return NULL;
}
struct txlocator *loc = talz(ctx, struct txlocator);
loc->blkheight = block->height;
size_t i, n = tal_count(block->txids);
for (i = 0; i < n; i++) {
if (structeq(&block->txids[i], txid)){
loc->index = block->txnums[i];
return loc;
}
}
return tal_free(loc);
}
static void json_dev_broadcast(struct command *cmd,
const char *buffer, const jsmntok_t *params)
{
jsmntok_t *enabletok;
bool enable;
if (!json_get_params(buffer, params,
"enable", &enabletok,
NULL)) {
command_fail(cmd, "Need enable");
return;
}
if (!json_tok_bool(buffer, enabletok, &enable)) {
command_fail(cmd, "enable must be true or false");
return;
}
log_debug(cmd->dstate->base_log, "dev-broadcast: broadcast %s",
enable ? "enabled" : "disabled");
cmd->dstate->dev_no_broadcast = !enable;
/* If enabling, flush and wait. */
if (enable)
rebroadcast_txs(cmd->dstate, cmd);
else
command_success(cmd, null_response(cmd));
}
static const struct json_command dev_broadcast_command = {
"dev-broadcast",
json_dev_broadcast,
"Pretend we broadcast txs, but don't send to bitcoind",
"Returns an empty result on success (waits for flush if enabled)"
};
AUTODATA(json_command, &dev_broadcast_command);
void setup_topology(struct lightningd_state *dstate)
{
dstate->topology = tal(dstate, struct topology);
block_map_init(&dstate->topology->block_map);
dstate->topology->startup = true;
dstate->topology->feerate = 0;
bitcoind_getblockcount(dstate, get_init_blockhash, NULL);
/* Once it gets topology, it calls io_break() and we return. */
io_loop(NULL, NULL);
assert(!dstate->topology->startup);
}