From 9463e1b63035b0ca3142f656ff42c297ecfbc20f Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Wed, 9 Nov 2016 08:04:28 +1030
Subject: [PATCH] wallet: use pubkey as API, not pointer.

Much easier to save/restore to/from database in coming patch.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 daemon/peer.c   | 11 +++++------
 daemon/peer.h   |  2 +-
 daemon/wallet.c | 36 ++++++++++++++++++++++++++++--------
 daemon/wallet.h | 10 +++++-----
 4 files changed, 39 insertions(+), 20 deletions(-)

diff --git a/daemon/peer.c b/daemon/peer.c
index 993407bfe..1bfe73ac0 100644
--- a/daemon/peer.c
+++ b/daemon/peer.c
@@ -542,7 +542,8 @@ static void bitcoin_create_anchor(struct peer *peer)
 	tx->input[0].amount = tal_dup(tx->input, u64,
 				      &peer->anchor.input->amount);
 
-	wallet_add_signed_input(peer->dstate, peer->anchor.input->w, tx, 0);
+	wallet_add_signed_input(peer->dstate, &peer->anchor.input->walletkey,
+				tx, 0);
 
 	bitcoin_txid(tx, &peer->anchor.txid);
 	peer->anchor.tx = tx;
@@ -3150,14 +3151,12 @@ static void json_connect(struct command *cmd,
 	bitcoin_txid(tx, &connect->input->txid);
 
 	/* Find an output we know how to spend. */
-	connect->input->w = NULL;
 	for (output = 0; output < tx->output_count; output++) {
-		connect->input->w
-			= wallet_can_spend(cmd->dstate, &tx->output[output]);
-		if (connect->input->w)
+		if (wallet_can_spend(cmd->dstate, &tx->output[output],
+				     &connect->input->walletkey))
 			break;
 	}
-	if (!connect->input->w) {
+	if (output == tx->output_count) {
 		command_fail(cmd, "Tx doesn't send to wallet address");
 		return;
 	}
diff --git a/daemon/peer.h b/daemon/peer.h
index 9c68f1f23..7aa5219bc 100644
--- a/daemon/peer.h
+++ b/daemon/peer.h
@@ -25,7 +25,7 @@ struct anchor_input {
 	/* Amount of input (satoshis) */
 	u64 amount;
 	/* Wallet entry to use to spend. */
-	struct wallet *w;
+	struct pubkey walletkey;
 };
 
 /* Information we remember for their commitment txs which we signed.
diff --git a/daemon/wallet.c b/daemon/wallet.c
index 0f7269748..650cda713 100644
--- a/daemon/wallet.c
+++ b/daemon/wallet.c
@@ -50,15 +50,31 @@ static void new_keypair(struct lightningd_state *dstate,
 	} while (!pubkey_from_privkey(dstate->secpctx, privkey, pubkey));
 }
 
-void wallet_add_signed_input(struct lightningd_state *dstate,
-			     const struct wallet *w,
+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;
-	assert(input_num < tx->input_count);
+	struct wallet *w = find_by_pubkey(dstate, walletkey);
 
+	assert(input_num < tx->input_count);
+	if (!w)
+		return false;
+	
 	redeemscript = bitcoin_redeem_p2wpkh(tx, dstate->secpctx, &w->pubkey);
 
 	sig.stype = SIGHASH_ALL;
@@ -75,10 +91,12 @@ void wallet_add_signed_input(struct lightningd_state *dstate,
 				    &sig,
 				    &w->pubkey);
 	tal_free(redeemscript);
+	return true;
 }
 
-struct wallet *wallet_can_spend(struct lightningd_state *dstate,
-				const struct bitcoin_tx_output *output)
+bool wallet_can_spend(struct lightningd_state *dstate,
+		      const struct bitcoin_tx_output *output,
+		      struct pubkey *walletkey)
 {
 	struct ripemd160 h;
 	struct wallet *w;
@@ -88,10 +106,12 @@ struct wallet *wallet_can_spend(struct lightningd_state *dstate,
 
 	memcpy(&h, output->script + 2, 20);
 	list_for_each(&dstate->wallet, w, list) {
-		if (structeq(&h, &w->p2sh))
-			return w;
+		if (structeq(&h, &w->p2sh)) {
+			*walletkey = w->pubkey;
+			return true;
+		}
 	}
-	return NULL;
+	return false;
 }
 	
 static void json_newaddr(struct command *cmd,
diff --git a/daemon/wallet.h b/daemon/wallet.h
index ebcd59f81..753542d1c 100644
--- a/daemon/wallet.h
+++ b/daemon/wallet.h
@@ -2,7 +2,6 @@
 #define LIGHTNING_DAEMON_WALLET_H
 #include "config.h"
 
-struct wallet;
 struct lightningd_state;
 struct bitcoin_tx;
 struct bitcoin_tx_output;
@@ -10,12 +9,13 @@ struct bitcoin_tx_output;
 bool restore_wallet_address(struct lightningd_state *dstate,
 			    const struct privkey *privkey);
 
-void wallet_add_signed_input(struct lightningd_state *dstate,
-			     const struct wallet *w,
+bool wallet_add_signed_input(struct lightningd_state *dstate,
+			     const struct pubkey *walletkey,
 			     struct bitcoin_tx *tx,
 			     unsigned int input_num);
 
-struct wallet *wallet_can_spend(struct lightningd_state *dstate,
-				const struct bitcoin_tx_output *output);
+bool wallet_can_spend(struct lightningd_state *dstate,
+		      const struct bitcoin_tx_output *output,
+		      struct pubkey *walletkey);
 
 #endif /* LIGHTNING_DAEMON_WALLET_H */