include/libeosio/WIF.hpp: adding signature encode/decode functions.

include/libeosio/WIF.hpp

@@ -54,6 +54,20 @@ bool wif_pub_decode(ec_pubkey_t& pub, const std::string& data, size_t prefix_len
  */
 void wif_print_key(const struct ec_keypair *key, const std::string& prefix = "EOS");
 
+/**
+ * Signatures
+ */
+
+/**
+ * Encode an EC signature to WIF String.
+ */
+std::string wif_sig_encode(const ec_signature_t& sig);
+
+/**
+ * Decode an WIF String to EC signature
+ */
+bool wif_sig_decode(ec_signature_t& sig, const std::string& data);
+
 } // namespace libeosio
 
 #endif /* LIBEOSIO_WIF_H */

src/WIF.cpp

@@ -112,4 +112,60 @@ void wif_print_key(const struct ec_keypair *key, const std::string& prefix) {
 	std::cout << "Private: " << wif_priv_encode(key->secret) << std::endl;
 }
 
+// Just to make it "harder" the calculated checksum for a signature
+// has a "K1" suffix that is not present in the WIF encoded string.
+// So this function is a quick hack to calculate it.
+//
+// Should implement and use Init/Update/Finalize hash functions to do it inplace.
+checksum_t _calculate_sig_checksum(const unsigned char *in) {
+	unsigned char buf[EC_SIGNATURE_SIZE + 2];
+
+	memcpy(buf, in, EC_SIGNATURE_SIZE);
+	memcpy(buf + EC_SIGNATURE_SIZE, "K1", 2);
+
+	return checksum_ripemd160(buf, EC_SIGNATURE_SIZE + 2);
+}
+
+bool wif_sig_decode(ec_signature_t& sig, const std::string& data) {
+
+	checksum_t checksum;
+	std::vector<unsigned char> buf;
+
+	if (data.substr(0, 7) != "SIG_K1_") {
+		// Invalid prefix
+		return false;
+	}
+
+	if (!base58_decode(data.c_str() + 7, buf)) {
+		return false;
+	}
+
+	if (buf.size() != EC_SIGNATURE_SIZE + CHECKSUM_SIZE) {
+		return false;
+	}
+
+	// Calculate checksum
+	checksum = _calculate_sig_checksum(buf.data());
+
+	// And validate
+	if (memcmp(buf.data() + EC_SIGNATURE_SIZE, checksum.data(), CHECKSUM_SIZE)) {
+		return false;
+	}
+
+	// Copy data to output
+	memcpy(sig.data(), buf.data(), sig.size());
+	return true;
+}
+
+std::string wif_sig_encode(const ec_signature_t& sig) {
+
+	unsigned char buf[EC_SIGNATURE_SIZE + CHECKSUM_SIZE];
+	checksum_t check = _calculate_sig_checksum(sig.data());
+
+	memcpy(buf, sig.data(), sig.size());
+	memcpy(buf + EC_SIGNATURE_SIZE, check.data(), check.size());
+
+	return "SIG_K1_" + base58_encode(buf, buf + sizeof(buf));
+}
+
 } // namespace libeosio

tests/CMakeLists.txt

@@ -16,7 +16,8 @@ set(TEST_SRC
 	WIF/priv_decode.cpp
 	WIF/pub_encode.cpp
 	WIF/pub_decode.cpp
-)
+	WIF/sig_encode.cpp
+	WIF/sig_decode.cpp)
 
 add_executable(doctest ${TEST_SRC})
 target_link_libraries(doctest PRIVATE ${LIB_NAME})

tests/WIF/sig_decode.cpp

@@ -0,0 +1,100 @@
+#include <libeosio/WIF.hpp>
+#include <libeosio/ec.hpp>
+#include <vector>
+#include <doctest.h>
+
+TEST_CASE("WIF::wif_sig_decode") {
+
+	struct testcase {
+		const char *name;
+		std::string input;
+		libeosio::ec_signature_t expected;
+		bool expectedRet;
+	};
+
+	std::vector<testcase> tests = {
+		{
+			"valid #1",
+			"SIG_K1_KYq4LKCQ1Pdk38TY4FqwxiHRQd53b2kffB7G2Lt5WiV8VzZAvwCdbRVC5AjZvEkmXSEwyFkAFACHj1hYos8hB7Ass7RY2f",
+			{
+				0x20,0x1f,0x32,0xfb,0x5f,0x24,0xd2,0x57,
+				0x5c,0xcc,0x51,0xf3,0xf1,0x60,0x47,0xf7,
+				0x5c,0x5e,0x8e,0xb0,0xb1,0xc2,0x6d,0x76,
+				0x07,0xc1,0x9e,0x24,0xd7,0xbb,0xc1,0x69,
+				0x9a,0x04,0xba,0xa7,0x32,0xc7,0xef,0x83,
+				0x1d,0xa9,0x40,0xde,0x9c,0xc8,0xf1,0xd9,
+				0x7b,0xe5,0x0e,0xaf,0x90,0xdf,0xce,0x98,
+				0xc5,0x34,0x55,0x04,0x9b,0x20,0x72,0x9a,
+				0x96
+			},
+			true
+		},
+		{
+			"valid #2",
+			"SIG_K1_K2Liiq4wXeeWfndxGM23xms5AR5oK99RvKRR9NpW9eemKWKD1FmpmnwEbpZUSBzQC77KwYptvW6cwGjWR6D3qDddH3w69J",
+			{
+				0x1f,0x36,0x28,0x1c,0xe3,0xda,0x53,0x40,
+				0x09,0x28,0xa8,0xad,0x68,0xb3,0x3a,0xb7,
+				0x90,0xf7,0x55,0xff,0x60,0xf0,0x51,0x9b,
+				0xb6,0xd8,0x48,0xff,0x09,0xbb,0x5d,0x17,
+				0xa2,0x1a,0xe0,0x55,0xe5,0x75,0xf4,0xb9,
+				0x67,0x5a,0x42,0x2c,0xf3,0x8f,0x40,0x32,
+				0x1d,0x76,0x23,0x54,0xae,0xdc,0xfb,0xb9,
+				0xf3,0x16,0x88,0x3e,0x62,0xec,0x7f,0x0d,
+				0x9f
+			},
+			true
+		},
+		{
+			"valid #3",
+			"SIG_K1_Jxm4D2csP298MurVbsntqZvU6RrMvLufVGQ1URtjdKQ6tdbkkifW5ptcbhW7oGP9nfJ6rzW7Jqhgu2RsDm9ToDyCmy9yk7",
+			{
+				0x1f,0x1a,0xca,0x19,0x60,0x39,0x18,0x63,0x53,0x18,0xea,0x29,0x6e,0x4a,0x16,0x81,0x8f,0xf0,0xdc,0xe,0xad,0x38,0x1e,0x5f,0x0,0xde,0xb1,0xd5,0x1d,0xf5,0xe4,0xfb,0x8e,0x6d,0xdd,0x5d,0x79,0xe2,0x1,0x5d,0xac,0x75,0x72,0xcd,0xe7,0x84,0x47,0x8d,0x49,0x68,0xa0,0x7f,0x31,0x22,0xbb,0x6d,0x49,0x9b,0x43,0x92,0x83,0xec,0xbf,0xf8,0x4
+			},
+			true
+		},
+		{
+			"invalid #1 - prefix",
+			"PREF_KaK2DE1we98JKmQRfEP1TXcySbHAfVqUBCqhZ2VtUo3v4QFyFNPg2YRmsiRHk5ePFxqxhX1Y8VS2NC5DYfhQyTFmouTLBi",
+			{},
+			false,
+		},
+		{
+			"invalid #2 - wrong checksum",
+			"SIG_K1_K2Liiq4wXeeWfndxGM23xms5AR5oK99RvKRR9NpW9eemKWKD1FmpmnwEbpZUSBzQC77KwYptvW6cwGjWR6D3qDddH3w6xx",
+			{},
+			false,
+		},
+		{
+			"invalid #3 - to long",
+			"SIG_K1_uns8EQ4m3QJgVPPNNNc9HFDgvmsXe7yrAB66nsCnNjhH3zhBvzoBLf22GtWDwmpUQWByr7VExHZ8aZnuTMEDkHEaS4dzP8oT2qupW7HsCzeRKfSXMZ48jKnMV4aqiK8VqH66KD9Mn",
+			{},
+			false,
+		},
+		{
+			"invalid #4 - to short",
+			"SIG_K1_8BTSpezp9ywsEwVPhMgMLgDMZV1xHuycq2DNbSrVcSZjriyK2FBrh5p518",
+			{},
+			false,
+		},
+		{
+			"invalid #5 - non-base58",
+			"SIG_K1_6sCX2LiY2EpKdJtK7DJMGUETSNdDBNP3MjoZlF1i2V6RFhjoqd1jZbIAobdeARzQxpqHBvJpOWhKxBdA28CsVYJQe0VdcL",
+			{},
+			false,
+		}
+	};
+
+	for(auto it = tests.begin(); it != tests.end(); it++) {
+		SUBCASE(it->name) {
+			libeosio::ec_signature_t result;
+
+			CHECK( libeosio::wif_sig_decode(result, it->input) == it->expectedRet );
+
+			if (it->expectedRet == true) {
+				CHECK( result == it->expected );
+			}
+		}
+	}
+}
+

tests/WIF/sig_encode.cpp

@@ -0,0 +1,53 @@
+#include <libeosio/WIF.hpp>
+#include <libeosio/ec.hpp>
+#include <vector>
+#include <doctest.h>
+
+TEST_CASE("WIF::wif_sig_encode") {
+
+	struct testcase {
+		const char *name;
+		libeosio::ec_signature_t sig;
+		std::string expected;
+
+	};
+
+	std::vector<struct testcase> tests = {
+		{
+			"first",
+			{
+				0x20,0x1f,0x32,0xfb,0x5f,0x24,0xd2,0x57,
+				0x5c,0xcc,0x51,0xf3,0xf1,0x60,0x47,0xf7,
+				0x5c,0x5e,0x8e,0xb0,0xb1,0xc2,0x6d,0x76,
+				0x07,0xc1,0x9e,0x24,0xd7,0xbb,0xc1,0x69,
+				0x9a,0x04,0xba,0xa7,0x32,0xc7,0xef,0x83,
+				0x1d,0xa9,0x40,0xde,0x9c,0xc8,0xf1,0xd9,
+				0x7b,0xe5,0x0e,0xaf,0x90,0xdf,0xce,0x98,
+				0xc5,0x34,0x55,0x04,0x9b,0x20,0x72,0x9a,
+				0x96
+			},
+			"SIG_K1_KYq4LKCQ1Pdk38TY4FqwxiHRQd53b2kffB7G2Lt5WiV8VzZAvwCdbRVC5AjZvEkmXSEwyFkAFACHj1hYos8hB7Ass7RY2f"
+		},
+		{
+			"second",
+			{
+				0x1f,0x36,0x28,0x1c,0xe3,0xda,0x53,0x40,
+				0x09,0x28,0xa8,0xad,0x68,0xb3,0x3a,0xb7,
+				0x90,0xf7,0x55,0xff,0x60,0xf0,0x51,0x9b,
+				0xb6,0xd8,0x48,0xff,0x09,0xbb,0x5d,0x17,
+				0xa2,0x1a,0xe0,0x55,0xe5,0x75,0xf4,0xb9,
+				0x67,0x5a,0x42,0x2c,0xf3,0x8f,0x40,0x32,
+				0x1d,0x76,0x23,0x54,0xae,0xdc,0xfb,0xb9,
+				0xf3,0x16,0x88,0x3e,0x62,0xec,0x7f,0x0d,
+				0x9f
+			},
+			"SIG_K1_K2Liiq4wXeeWfndxGM23xms5AR5oK99RvKRR9NpW9eemKWKD1FmpmnwEbpZUSBzQC77KwYptvW6cwGjWR6D3qDddH3w69J"
+		},
+	};
+
+	for(auto it = tests.begin(); it != tests.end(); it++) {
+		SUBCASE(it->name) {
+			CHECK( libeosio::wif_sig_encode(it->sig) == it->expected );
+		}
+	}
+}