From 8f0140c542e6cbc70de5f061e4e28ceeca95a0c6 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Fri, 24 Jul 2015 16:00:11 +0930
Subject: [PATCH] script: remove now-unnecessary 2of2 ops.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 bitcoin/script.c    | 54 ---------------------------------------------
 bitcoin/script.h    | 12 ----------
 bitcoin/signature.c | 20 -----------------
 bitcoin/signature.h |  6 -----
 4 files changed, 92 deletions(-)

diff --git a/bitcoin/script.c b/bitcoin/script.c
index 7b342d463..c7c0f1865 100644
--- a/bitcoin/script.c
+++ b/bitcoin/script.c
@@ -104,36 +104,6 @@ static void add_push_sig(u8 **scriptp, const struct bitcoin_signature *sig)
 #endif
 }
 
-/* FIXME: permute? */
-/* Is a < b? (If equal we don't care) */
-static bool key_less(const struct pubkey *a, const struct pubkey *b)
-{
-	/* Shorter one wins. */
-	if (pubkey_len(a) != pubkey_len(b))
-		return pubkey_len(a) < pubkey_len(b);
-
-	return memcmp(a->key, b->key, pubkey_len(a)) < 0;
-}
-	
-/* tal_count() gives the length of the script. */
-u8 *bitcoin_redeem_2of2(const tal_t *ctx,
-			const struct pubkey *key1,
-			const struct pubkey *key2)
-{
-	u8 *script = tal_arr(ctx, u8, 0);
-	add_number(&script, 2);
-	if (key_less(key1, key2)) {
-		add_push_key(&script, key1);
-		add_push_key(&script, key2);
-	} else {
-		add_push_key(&script, key2);
-		add_push_key(&script, key1);
-	}
-	add_number(&script, 2);
-	add_op(&script, OP_CHECKMULTISIG);
-	return script;
-}
-
 /* tal_count() gives the length of the script. */
 u8 *bitcoin_redeem_single(const tal_t *ctx, const struct pubkey *key)
 {
@@ -183,30 +153,6 @@ u8 *scriptsig_p2sh_single_sig(const tal_t *ctx,
 	return script;
 }
 	
-u8 *scriptsig_p2sh_2of2(const tal_t *ctx,
-			const struct bitcoin_signature *sig1,
-			const struct bitcoin_signature *sig2,
-			const struct pubkey *key1,
-			const struct pubkey *key2)
-{
-	u8 *script = tal_arr(ctx, u8, 0);
-	u8 *redeemscript;
-
-	/* OP_CHECKMULTISIG has an out-by-one bug, which MBZ */
-	add_number(&script, 0);
-	/* sig order should match key order. */
-	if (key_less(key1, key2)) {
-		add_push_sig(&script, sig1);
-		add_push_sig(&script, sig2);
-	} else {
-		add_push_sig(&script, sig2);
-		add_push_sig(&script, sig1);
-	}
-	redeemscript = bitcoin_redeem_2of2(script, key1, key2);
-	add_push_bytes(&script, redeemscript, tal_count(redeemscript));
-	return script;
-}
-
 /* Is this a normal pay to pubkey hash? */
 bool is_pay_to_pubkey_hash(const u8 *script, size_t script_len)
 {
diff --git a/bitcoin/script.h b/bitcoin/script.h
index 2bf47ba96..798842024 100644
--- a/bitcoin/script.h
+++ b/bitcoin/script.h
@@ -15,11 +15,6 @@ struct bitcoin_signature {
 	enum sighash_type stype;
 };
 
-/* tal_count() gives the length of the script. */
-u8 *bitcoin_redeem_2of2(const tal_t *ctx,
-			const struct pubkey *key1,
-			const struct pubkey *key2);
-
 /* tal_count() gives the length of the script. */
 u8 *bitcoin_redeem_single(const tal_t *ctx, const struct pubkey *key);
 
@@ -48,13 +43,6 @@ u8 *scriptsig_pay_to_pubkeyhash(const tal_t *ctx,
 				const struct pubkey *key,
 				const struct bitcoin_signature *sig);
 
-/* Create an input script to accept pay to pubkey */
-u8 *scriptsig_p2sh_2of2(const tal_t *ctx,
-			const struct bitcoin_signature *sig1,
-			const struct bitcoin_signature *sig2,
-			const struct pubkey *key1,
-			const struct pubkey *key2);
-
 /* Create an input script to spend anchor output (commit version). */
 u8 *scriptsig_p2sh_anchor_commit(const tal_t *ctx,
 				 const struct bitcoin_signature *their_sig,
diff --git a/bitcoin/signature.c b/bitcoin/signature.c
index 34fb48a61..e6c6b7ed9 100644
--- a/bitcoin/signature.c
+++ b/bitcoin/signature.c
@@ -198,26 +198,6 @@ bool check_tx_sig(struct bitcoin_tx *tx, size_t input_num,
 	return ret;
 }
 
-bool check_2of2_sig(struct bitcoin_tx *tx, size_t input_num,
-		    const u8 *redeemscript, size_t redeemscript_len,
-		    const struct pubkey *key1, const struct pubkey *key2,
-		    const struct bitcoin_signature *sig1,
-		    const struct bitcoin_signature *sig2)
-{
-	struct sha256_double hash;
-	assert(input_num < tx->input_count);
-
-	sha256_tx_one_input(tx, input_num, redeemscript, redeemscript_len,
-			    &hash);
-
-	/* We only use SIGHASH_ALL for the moment. */
-	if (sig1->stype != SIGHASH_ALL || sig2->stype != SIGHASH_ALL)
-		return false;
-	
-	return check_signed_hash(&hash, &sig1->sig, key1)
-		&& check_signed_hash(&hash, &sig2->sig, key2);
-}
-
 /* Stolen direct from bitcoin/src/script/sign.cpp:
 // Copyright (c) 2009-2010 Satoshi Nakamoto
 // Copyright (c) 2009-2014 The Bitcoin Core developers
diff --git a/bitcoin/signature.h b/bitcoin/signature.h
index 34692f539..e0c56e09e 100644
--- a/bitcoin/signature.h
+++ b/bitcoin/signature.h
@@ -40,12 +40,6 @@ bool check_tx_sig(struct bitcoin_tx *tx, size_t input_num,
 		  const struct pubkey *key,
 		  const struct bitcoin_signature *sig);
 
-bool check_2of2_sig(struct bitcoin_tx *tx, size_t input_num,
-		    const u8 *redeemscript, size_t redeemscript_len,
-		    const struct pubkey *key1, const struct pubkey *key2,
-		    const struct bitcoin_signature *sig1,
-		    const struct bitcoin_signature *sig2);
-
 /* Signature must have low S value. */
 bool sig_valid(const struct signature *s);