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Add the RFC6979 PRNG

0.10
Pieter Wuille 10 years ago
parent
commit
3060e36098
  1. 2
      src/Makefile.am
  2. 47
      src/crypto/rfc6979_hmac_sha256.cpp
  3. 36
      src/crypto/rfc6979_hmac_sha256.h
  4. 36
      src/test/crypto_tests.cpp

2
src/Makefile.am

@ -206,12 +206,14 @@ crypto_libbitcoin_crypto_a_SOURCES = \ @@ -206,12 +206,14 @@ crypto_libbitcoin_crypto_a_SOURCES = \
crypto/sha256.cpp \
crypto/sha512.cpp \
crypto/hmac_sha256.cpp \
crypto/rfc6979_hmac_sha256.cpp \
crypto/hmac_sha512.cpp \
crypto/ripemd160.cpp \
crypto/common.h \
crypto/sha256.h \
crypto/sha512.h \
crypto/hmac_sha256.h \
crypto/rfc6979_hmac_sha256.h \
crypto/hmac_sha512.h \
crypto/sha1.h \
crypto/ripemd160.h

47
src/crypto/rfc6979_hmac_sha256.cpp

@ -0,0 +1,47 @@ @@ -0,0 +1,47 @@
// Copyright (c) 2014 The Bitcoin developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "crypto/rfc6979_hmac_sha256.h"
#include <string.h>
#include <algorithm>
static const unsigned char zero[1] = {0x00};
static const unsigned char one[1] = {0x01};
RFC6979_HMAC_SHA256::RFC6979_HMAC_SHA256(const unsigned char* key, size_t keylen, const unsigned char* msg, size_t msglen) : retry(false)
{
memset(V, 0x01, sizeof(V));
memset(K, 0x00, sizeof(K));
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Write(zero, sizeof(zero)).Write(key, keylen).Write(msg, msglen).Finalize(K);
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Finalize(V);
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Write(one, sizeof(one)).Write(key, keylen).Write(msg, msglen).Finalize(K);
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Finalize(V);
}
RFC6979_HMAC_SHA256::~RFC6979_HMAC_SHA256()
{
memset(V, 0x01, sizeof(V));
memset(K, 0x00, sizeof(K));
}
void RFC6979_HMAC_SHA256::Generate(unsigned char* output, size_t outputlen)
{
if (retry) {
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Write(zero, sizeof(zero)).Finalize(K);
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Finalize(V);
}
while (outputlen > 0) {
CHMAC_SHA256(K, sizeof(K)).Write(V, sizeof(V)).Finalize(V);
size_t len = std::min(outputlen, sizeof(V));
memcpy(output, V, len);
output += len;
outputlen -= len;
}
retry = true;
}

36
src/crypto/rfc6979_hmac_sha256.h

@ -0,0 +1,36 @@ @@ -0,0 +1,36 @@
// Copyright (c) 2014 The Bitcoin developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#ifndef BITCOIN_RFC6979_HMAC_SHA256_H
#define BITCOIN_RFC6979_HMAC_SHA256_H
#include "crypto/hmac_sha256.h"
#include <stdint.h>
#include <stdlib.h>
/** The RFC 6979 PRNG using HMAC-SHA256. */
class RFC6979_HMAC_SHA256
{
private:
unsigned char V[CHMAC_SHA256::OUTPUT_SIZE];
unsigned char K[CHMAC_SHA256::OUTPUT_SIZE];
bool retry;
public:
/**
* Construct a new RFC6979 PRNG, using the given key and message.
* The message is assumed to be already hashed.
*/
RFC6979_HMAC_SHA256(const unsigned char* key, size_t keylen, const unsigned char* msg, size_t msglen);
/**
* Generate a byte array.
*/
void Generate(unsigned char* output, size_t outputlen);
~RFC6979_HMAC_SHA256();
};
#endif // BITCOIN_RFC6979_HMAC_SHA256_H

36
src/test/crypto_tests.cpp

@ -2,6 +2,7 @@ @@ -2,6 +2,7 @@
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "crypto/rfc6979_hmac_sha256.h"
#include "crypto/ripemd160.h"
#include "crypto/sha1.h"
#include "crypto/sha256.h"
@ -13,6 +14,7 @@ @@ -13,6 +14,7 @@
#include <vector>
#include <boost/assign/list_of.hpp>
#include <boost/test/unit_test.hpp>
BOOST_AUTO_TEST_SUITE(crypto_tests)
@ -246,4 +248,38 @@ BOOST_AUTO_TEST_CASE(hmac_sha512_testvectors) { @@ -246,4 +248,38 @@ BOOST_AUTO_TEST_CASE(hmac_sha512_testvectors) {
"b6022cac3c4982b10d5eeb55c3e4de15134676fb6de0446065c97440fa8c6a58");
}
void TestRFC6979(const std::string& hexkey, const std::string& hexmsg, const std::vector<std::string>& hexout)
{
std::vector<unsigned char> key = ParseHex(hexkey);
std::vector<unsigned char> msg = ParseHex(hexmsg);
RFC6979_HMAC_SHA256 rng(&key[0], key.size(), &msg[0], msg.size());
for (unsigned int i = 0; i < hexout.size(); i++) {
std::vector<unsigned char> out = ParseHex(hexout[i]);
std::vector<unsigned char> gen;
gen.resize(out.size());
rng.Generate(&gen[0], gen.size());
BOOST_CHECK(out == gen);
}
}
BOOST_AUTO_TEST_CASE(rfc6979_hmac_sha256)
{
TestRFC6979(
"0102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f00",
"4bf5122f344554c53bde2ebb8cd2b7e3d1600ad631c385a5d7cce23c7785459a",
boost::assign::list_of
("4fe29525b2086809159acdf0506efb86b0ec932c7ba44256ab321e421e67e9fb")
("2bf0fff1d3c378a22dc5de1d856522325c65b504491a0cbd01cb8f3aa67ffd4a")
("f528b410cb541f77000d7afb6c5b53c5c471eab43e466d9ac5190c39c82fd82e"));
TestRFC6979(
"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF",
"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
boost::assign::list_of
("9c236c165b82ae0cd590659e100b6bab3036e7ba8b06749baf6981e16f1a2b95")
("df471061625bc0ea14b682feee2c9c02f235da04204c1d62a1536c6e17aed7a9")
("7597887cbd76321f32e30440679a22cf7f8d9d2eac390e581fea091ce202ba94"));
}
BOOST_AUTO_TEST_SUITE_END()

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