core-lightning/daemon/wallet.c
Rusty Russell a4fdaab5b3 Use global secp256k1_ctx instead of passing it around.
If I'd known how large this patch would be (though trivial), I'd
have done it in parts.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2016-12-02 18:12:58 +10:30

144 lines
3.5 KiB
C

/* Poor man's wallet.
* Needed because bitcoind doesn't (yet) produce segwit outputs, and we need
* such outputs for our anchor tx to make it immalleable.
*/
#include "bitcoin/base58.h"
#include "bitcoin/privkey.h"
#include "bitcoin/script.h"
#include "bitcoin/signature.h"
#include "bitcoin/tx.h"
#include "db.h"
#include "jsonrpc.h"
#include "lightningd.h"
#include "log.h"
#include "wallet.h"
#include <ccan/structeq/structeq.h>
#include <sodium/randombytes.h>
struct wallet {
struct list_node list;
struct privkey privkey;
struct pubkey pubkey;
struct ripemd160 p2sh;
};
bool restore_wallet_address(struct lightningd_state *dstate,
const struct privkey *privkey)
{
struct wallet *w = tal(dstate, struct wallet);
u8 *redeemscript;
struct sha256 h;
w->privkey = *privkey;
if (!pubkey_from_privkey(&w->privkey, &w->pubkey))
return false;
redeemscript = bitcoin_redeem_p2wpkh(w, &w->pubkey);
sha256(&h, redeemscript, tal_count(redeemscript));
ripemd160(&w->p2sh, h.u.u8, sizeof(h));
list_add_tail(&dstate->wallet, &w->list);
tal_free(redeemscript);
return true;
}
static void new_keypair(struct privkey *privkey, struct pubkey *pubkey)
{
do {
randombytes_buf(privkey->secret, sizeof(privkey->secret));
} while (!pubkey_from_privkey(privkey, pubkey));
}
static struct wallet *find_by_pubkey(struct lightningd_state *dstate,
const struct pubkey *walletkey)
{
struct wallet *w;
list_for_each(&dstate->wallet, w, list) {
if (pubkey_eq(walletkey, &w->pubkey))
return w;
}
return NULL;
}
bool wallet_add_signed_input(struct lightningd_state *dstate,
const struct pubkey *walletkey,
struct bitcoin_tx *tx,
unsigned int input_num)
{
u8 *redeemscript;
struct bitcoin_signature sig;
struct wallet *w = find_by_pubkey(dstate, walletkey);
assert(input_num < tx->input_count);
if (!w)
return false;
redeemscript = bitcoin_redeem_p2wpkh(tx, &w->pubkey);
sig.stype = SIGHASH_ALL;
sign_tx_input(tx, input_num,
redeemscript, tal_count(redeemscript),
p2wpkh_scriptcode(redeemscript, &w->pubkey),
&w->privkey,
&w->pubkey,
&sig.sig);
bitcoin_witness_p2sh_p2wpkh(tx->input,
&tx->input[input_num],
&sig,
&w->pubkey);
tal_free(redeemscript);
return true;
}
bool wallet_can_spend(struct lightningd_state *dstate,
const struct bitcoin_tx_output *output,
struct pubkey *walletkey)
{
struct ripemd160 h;
struct wallet *w;
if (!is_p2sh(output->script, output->script_length))
return NULL;
memcpy(&h, output->script + 2, 20);
list_for_each(&dstate->wallet, w, list) {
if (structeq(&h, &w->p2sh)) {
*walletkey = w->pubkey;
return true;
}
}
return false;
}
static void json_newaddr(struct command *cmd,
const char *buffer, const jsmntok_t *params)
{
struct json_result *response = new_json_result(cmd);
struct wallet *w = tal(cmd->dstate, struct wallet);
u8 *redeemscript;
struct sha256 h;
new_keypair(&w->privkey, &w->pubkey);
redeemscript = bitcoin_redeem_p2wpkh(cmd, &w->pubkey);
sha256(&h, redeemscript, tal_count(redeemscript));
ripemd160(&w->p2sh, h.u.u8, sizeof(h));
list_add_tail(&cmd->dstate->wallet, &w->list);
db_add_wallet_privkey(cmd->dstate, &w->privkey);
json_object_start(response, NULL);
json_add_string(response, "address",
p2sh_to_base58(cmd, cmd->dstate->testnet, &w->p2sh));
json_object_end(response);
command_success(cmd, response);
}
const struct json_command newaddr_command = {
"newaddr",
json_newaddr,
"Get a new address to fund a channel",
"Returns {address} a p2sh address"
};