add script parsing functions

Makefile

@@ -37,6 +37,7 @@ CFLAGS += -DUSE_PRECOMPUTED_IV=0 -DUSE_PRECOMPUTED_CP=0
 endif
 
 SRCS   = bignum.c ecdsa.c curves.c secp256k1.c nist256p1.c rand.c hmac.c bip32.c bip39.c pbkdf2.c base58.c
+SRCS  += script.c
 SRCS  += ripemd160.c
 SRCS  += sha2.c
 SRCS  += sha3.c

script.c

@@ -0,0 +1,64 @@
+/**
+ * Copyright (c) 2016 Pavol Rusnak
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <string.h>
+#include "base58.h"
+#include "script.h"
+
+int script_output_to_address(const uint8_t *script, int scriptlen, char *addr, int addrsize)
+{
+	uint8_t raw[35];
+
+	// P2PKH
+	if (scriptlen == 25 && script[0] == 0x76 && script[1] == 0xA9 && script[2] == 0x14 && script[23] == 0x88 && script[24] == 0xAC) {
+		raw[0] = 0x00;
+		memcpy(raw + 1, script + 3, 20);
+		return base58_encode_check(raw, 1 + 20, addr, addrsize);
+	}
+
+	// P2SH
+	if (scriptlen == 23 && script[0] == 0xA9 && script[1] == 0x14 && script[22] == 0x87) {
+		raw[0] = 0x05;
+		memcpy(raw + 1, script + 2, 20);
+		return base58_encode_check(raw, 1 + 20, addr, addrsize);
+	}
+
+	// P2WPKH
+	if (scriptlen == 22 && script[0] == 0x00 && script[1] == 0x14) {
+		raw[0] = 0x06;
+		raw[1] = 0x00;
+		raw[2] = 0x00;
+		memcpy(raw + 3, script + 2, 20);
+		return base58_encode_check(raw, 3 + 20, addr, addrsize);
+	}
+
+	// P2WSH
+	if (scriptlen == 34 && script[0] == 0x00 && script[1] == 0x20) {
+		raw[0] = 0x0A;
+		raw[1] = 0x00;
+		raw[2] = 0x00;
+		memcpy(raw + 3, script + 2, 32);
+		return base58_encode_check(raw, 3 + 32, addr, addrsize);
+	}
+
+	return 0;
+}

script.h

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2016 Pavol Rusnak
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __SCRIPT_H__
+#define __SCRIPT_H__
+
+#include <stdint.h>
+
+int script_output_to_address(const uint8_t *script, int scriptlen, char *addr, int addrsize);
+
+#endif

tests.c

@@ -42,6 +42,7 @@
 #include "secp256k1.h"
 #include "nist256p1.h"
 #include "ed25519.h"
+#include "script.h"
 
 uint8_t *fromhex(const char *str)
 {
@@ -1872,6 +1873,28 @@ START_TEST(test_ed25519) {
 }
 END_TEST
 
+START_TEST(test_output_script) {
+	static const char *vectors[] = {
+		"76A914010966776006953D5567439E5E39F86A0D273BEE88AC", "16UwLL9Risc3QfPqBUvKofHmBQ7wMtjvM",
+		"A914010966776006953D5567439E5E39F86A0D273BEE87", "31nVrspaydBz8aMpxH9WkS2DuhgqS1fCuG",
+		"0014010966776006953D5567439E5E39F86A0D273BEE", "p2xtZoXeX5X8BP8JfFhQK2nD3emtjch7UeFm",
+		"00200102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F20", "7XhPD7te3C6CVKnJWUhrTJbFTwudhHqfrjpS59AS6sMzL4RYFiCNg",
+		0, 0,
+	};
+	const char **scr, **adr;
+	scr = vectors;
+	adr = vectors + 1;
+	char address[60];
+	while (*scr && *adr) {
+		int r = script_output_to_address(fromhex(*scr), strlen(*scr)/2, address, 60);
+		ck_assert_int_eq(r, strlen(*adr) + 1);
+		ck_assert_str_eq(address, *adr);
+		scr += 2;
+		adr += 2;
+	}
+}
+END_TEST
+
 
 // define test suite and cases
 Suite *test_suite(void)
@@ -1975,6 +1998,10 @@ Suite *test_suite(void)
 	tcase_add_test(tc, test_ed25519);
 	suite_add_tcase(s, tc);
 
+	tc = tcase_create("script");
+	tcase_add_test(tc, test_output_script);
+	suite_add_tcase(s, tc);
+
 	return s;
 }