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#include "bitcoin/pubkey.h"
#include "bitcoin/script.h"
#include "bitcoin/shadouble.h"
#include "bitcoin/tx.h"
#include "commit_tx.h"
#include "overflows.h"
#include "permute_tx.h"
#include "pkt.h"
#include "protobuf_convert.h"
struct bitcoin_tx *create_commit_tx(const tal_t *ctx,
OpenChannel *ours,
OpenChannel *theirs,
const struct sha256 *rhash,
int64_t delta,
const struct sha256_double *anchor_txid1,
unsigned int index1, uint64_t input_amount1,
const struct sha256_double *anchor_txid2,
unsigned int index2, uint64_t input_amount2,
size_t inmap[2])
{
struct bitcoin_tx *tx;
const u8 *redeemscript;
struct pubkey ourkey, theirkey, to_me;
u32 locktime;
/* Now create commitment tx: two inputs, two outputs. */
tx = bitcoin_tx(ctx, 2, 2);
/* Our inputs spend the anchor txs outputs. */
tx->input[0].txid = *anchor_txid1;
tx->input[0].index = index1;
tx->input[0].input_amount = input_amount1;
tx->input[1].txid = *anchor_txid2;
tx->input[1].index = index2;
tx->input[1].input_amount = input_amount2;
if (add_overflows_u64(tx->input[0].input_amount,
tx->input[1].input_amount))
return tal_free(tx);
/* Output goes to our final pubkeys */
if (!proto_to_pubkey(ours->final, &ourkey))
return tal_free(tx);
if (!proto_to_pubkey(theirs->final, &theirkey))
return tal_free(tx);
if (!proto_to_locktime(theirs, &locktime))
return tal_free(tx);
/* First output is a P2SH to a complex redeem script (usu. for me) */
redeemscript = bitcoin_redeem_secret_or_delay(tx, &ourkey,
locktime,
&theirkey,
rhash);
tx->output[0].script = scriptpubkey_p2sh(tx, redeemscript);
tx->output[0].script_length = tal_count(tx->output[0].script);
if (ours->total_input < ours->commitment_fee)
return tal_free(tx);
tx->output[0].amount = ours->total_input - ours->commitment_fee;
/* Asking for more than we have? */
if (delta < 0 && -delta > tx->output[0].amount)
return tal_free(tx);
tx->output[0].amount += delta;
/* Second output is a P2SH payment to them. */
if (!proto_to_pubkey(theirs->final, &to_me))
return tal_free(tx);
tx->output[1].script = scriptpubkey_p2sh(ctx,
bitcoin_redeem_single(ctx,
&to_me));
tx->output[1].script_length = tal_count(tx->output[1].script);
if (theirs->total_input < theirs->commitment_fee)
return tal_free(tx);
tx->output[1].amount = theirs->total_input - theirs->commitment_fee;
/* Asking for more than they have? */
if (delta > 0 && delta > tx->output[1].amount)
return tal_free(tx);
tx->output[0].amount -= delta;
/* Calculate fee; difference of inputs and outputs. */
tx->fee = tx->input[0].input_amount + tx->input[1].input_amount
- (tx->output[0].amount + tx->output[1].amount);
permute_inputs(tx->input, 2, inmap);
permute_outputs(tx->output, 2, NULL);
return tx;
}