monero/src/crypto/slow-hash.c
2014-10-06 17:44:23 -04:00

621 lines
20 KiB
C

// Copyright (c) 2014, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
#include <assert.h>
#include <stddef.h>
#include <stdint.h>
#include <string.h>
#include "common/int-util.h"
#include "hash-ops.h"
#include "oaes_lib.h"
#include <emmintrin.h>
#if defined(_MSC_VER)
#include <intrin.h>
#include <windows.h>
#define STATIC
#define INLINE __inline
#if !defined(RDATA_ALIGN16)
#define RDATA_ALIGN16 __declspec(align(16))
#endif
#elif defined(__MINGW32__)
#include <intrin.h>
#include <windows.h>
#define STATIC static
#define INLINE inline
#if !defined(RDATA_ALIGN16)
#define RDATA_ALIGN16 __attribute__ ((aligned(16)))
#endif
#else
#include <wmmintrin.h>
#include <sys/mman.h>
#define STATIC static
#define INLINE inline
#if !defined(RDATA_ALIGN16)
#define RDATA_ALIGN16 __attribute__ ((aligned(16)))
#endif
#endif
#if defined(__INTEL_COMPILER)
#define ASM __asm__
#elif !defined(_MSC_VER)
#define ASM __asm__
#else
#define ASM __asm
#endif
#define MEMORY (1 << 21) // 2MB scratchpad
#define ITER (1 << 20)
#define AES_BLOCK_SIZE 16
#define AES_KEY_SIZE 32
#define INIT_SIZE_BLK 8
#define INIT_SIZE_BYTE (INIT_SIZE_BLK * AES_BLOCK_SIZE)
#define TOTALBLOCKS (MEMORY / AES_BLOCK_SIZE)
#define U64(x) ((uint64_t *) (x))
#define R128(x) ((__m128i *) (x))
#define state_index(x) (((*((uint64_t *)x) >> 4) & (TOTALBLOCKS - 1)) << 4)
#if defined(_MSC_VER)
#if !defined(_WIN64)
#define __mul() lo = mul128(c[0], b[0], &hi);
#else
#define __mul() lo = _umul128(c[0], b[0], &hi);
#endif
#else
#if defined(__x86_64__)
#define __mul() ASM("mulq %3\n\t" : "=d"(hi), "=a"(lo) : "%a" (c[0]), "rm" (b[0]) : "cc");
#else
#define __mul() lo = mul128(c[0], b[0], &hi);
#endif
#endif
#define pre_aes() \
j = state_index(a); \
_c = _mm_load_si128(R128(&hp_state[j])); \
_a = _mm_load_si128(R128(a)); \
/*
* An SSE-optimized implementation of the second half of CryptoNight step 3.
* After using AES to mix a scratchpad value into _c (done by the caller),
* this macro xors it with _b and stores the result back to the same index (j) that it
* loaded the scratchpad value from. It then performs a second random memory
* read/write from the scratchpad, but this time mixes the values using a 64
* bit multiply.
* This code is based upon an optimized implementation by dga.
*/
#define post_aes() \
_mm_store_si128(R128(c), _c); \
_b = _mm_xor_si128(_b, _c); \
_mm_store_si128(R128(&hp_state[j]), _b); \
j = state_index(c); \
p = U64(&hp_state[j]); \
b[0] = p[0]; b[1] = p[1]; \
__mul(); \
a[0] += hi; a[1] += lo; \
p = U64(&hp_state[j]); \
p[0] = a[0]; p[1] = a[1]; \
a[0] ^= b[0]; a[1] ^= b[1]; \
_b = _c; \
#if defined(_MSC_VER)
#define THREADV __declspec(thread)
#else
#define THREADV __thread
#endif
extern int aesb_single_round(const uint8_t *in, uint8_t*out, const uint8_t *expandedKey);
extern int aesb_pseudo_round(const uint8_t *in, uint8_t *out, const uint8_t *expandedKey);
#pragma pack(push, 1)
union cn_slow_hash_state
{
union hash_state hs;
struct
{
uint8_t k[64];
uint8_t init[INIT_SIZE_BYTE];
};
};
#pragma pack(pop)
THREADV uint8_t *hp_state = NULL;
THREADV int hp_allocated = 0;
#if defined(_MSC_VER)
#define cpuid(info,x) __cpuidex(info,x,0)
#else
void cpuid(int CPUInfo[4], int InfoType)
{
ASM __volatile__
(
"cpuid":
"=a" (CPUInfo[0]),
"=b" (CPUInfo[1]),
"=c" (CPUInfo[2]),
"=d" (CPUInfo[3]) :
"a" (InfoType), "c" (0)
);
}
#endif
/**
* @brief a = (a xor b), where a and b point to 128 bit values
*/
STATIC INLINE void xor_blocks(uint8_t *a, const uint8_t *b)
{
U64(a)[0] ^= U64(b)[0];
U64(a)[1] ^= U64(b)[1];
}
/**
* @brief uses cpuid to determine if the CPU supports the AES instructions
* @return true if the CPU supports AES, false otherwise
*/
STATIC INLINE int check_aes_hw(void)
{
int cpuid_results[4];
static int supported = -1;
if(supported >= 0)
return supported;
cpuid(cpuid_results,1);
return supported = cpuid_results[2] & (1 << 25);
}
STATIC INLINE void aes_256_assist1(__m128i* t1, __m128i * t2)
{
__m128i t4;
*t2 = _mm_shuffle_epi32(*t2, 0xff);
t4 = _mm_slli_si128(*t1, 0x04);
*t1 = _mm_xor_si128(*t1, t4);
t4 = _mm_slli_si128(t4, 0x04);
*t1 = _mm_xor_si128(*t1, t4);
t4 = _mm_slli_si128(t4, 0x04);
*t1 = _mm_xor_si128(*t1, t4);
*t1 = _mm_xor_si128(*t1, *t2);
}
STATIC INLINE void aes_256_assist2(__m128i* t1, __m128i * t3)
{
__m128i t2, t4;
t4 = _mm_aeskeygenassist_si128(*t1, 0x00);
t2 = _mm_shuffle_epi32(t4, 0xaa);
t4 = _mm_slli_si128(*t3, 0x04);
*t3 = _mm_xor_si128(*t3, t4);
t4 = _mm_slli_si128(t4, 0x04);
*t3 = _mm_xor_si128(*t3, t4);
t4 = _mm_slli_si128(t4, 0x04);
*t3 = _mm_xor_si128(*t3, t4);
*t3 = _mm_xor_si128(*t3, t2);
}
/**
* @brief expands 'key' into a form it can be used for AES encryption.
*
* This is an SSE-optimized implementation of AES key schedule generation. It
* expands the key into multiple round keys, each of which is used in one round
* of the AES encryption used to fill (and later, extract randomness from)
* the large 2MB buffer. Note that CryptoNight does not use a completely
* standard AES encryption for its buffer expansion, so do not copy this
* function outside of Monero without caution! This version uses the hardware
* AESKEYGENASSIST instruction to speed key generation, and thus requires
* CPU AES support.
* For more information about these functions, see page 19 of Intel's AES instructions
* white paper:
* http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/aes-instructions-set-white-paper.pdf
*
* @param key the input 128 bit key
* @param expandedKey An output buffer to hold the generated key schedule
*/
STATIC INLINE void aes_expand_key(const uint8_t *key, uint8_t *expandedKey)
{
__m128i *ek = R128(expandedKey);
__m128i t1, t2, t3;
t1 = _mm_loadu_si128(R128(key));
t3 = _mm_loadu_si128(R128(key + 16));
ek[0] = t1;
ek[1] = t3;
t2 = _mm_aeskeygenassist_si128(t3, 0x01);
aes_256_assist1(&t1, &t2);
ek[2] = t1;
aes_256_assist2(&t1, &t3);
ek[3] = t3;
t2 = _mm_aeskeygenassist_si128(t3, 0x02);
aes_256_assist1(&t1, &t2);
ek[4] = t1;
aes_256_assist2(&t1, &t3);
ek[5] = t3;
t2 = _mm_aeskeygenassist_si128(t3, 0x04);
aes_256_assist1(&t1, &t2);
ek[6] = t1;
aes_256_assist2(&t1, &t3);
ek[7] = t3;
t2 = _mm_aeskeygenassist_si128(t3, 0x08);
aes_256_assist1(&t1, &t2);
ek[8] = t1;
aes_256_assist2(&t1, &t3);
ek[9] = t3;
t2 = _mm_aeskeygenassist_si128(t3, 0x10);
aes_256_assist1(&t1, &t2);
ek[10] = t1;
}
/**
* @brief a "pseudo" round of AES (similar to but slightly different from normal AES encryption)
*
* To fill its 2MB scratch buffer, CryptoNight uses a nonstandard implementation
* of AES encryption: It applies 10 rounds of the basic AES encryption operation
* to an input 128 bit chunk of data <in>. Unlike normal AES, however, this is
* all it does; it does not perform the initial AddRoundKey step (this is done
* in subsequent steps by aesenc_si128), and it does not use the simpler final round.
* Hence, this is a "pseudo" round - though the function actually implements 10 rounds together.
*
* Note that unlike aesb_pseudo_round, this function works on multiple data chunks.
*
* @param in a pointer to nblocks * 128 bits of data to be encrypted
* @param out a pointer to an nblocks * 128 bit buffer where the output will be stored
* @param expandedKey the expanded AES key
* @param nblocks the number of 128 blocks of data to be encrypted
*/
STATIC INLINE void aes_pseudo_round(const uint8_t *in, uint8_t *out,
const uint8_t *expandedKey, int nblocks)
{
__m128i *k = R128(expandedKey);
__m128i d;
int i;
for(i = 0; i < nblocks; i++)
{
d = _mm_loadu_si128(R128(in + i * AES_BLOCK_SIZE));
d = _mm_aesenc_si128(d, *R128(&k[0]));
d = _mm_aesenc_si128(d, *R128(&k[1]));
d = _mm_aesenc_si128(d, *R128(&k[2]));
d = _mm_aesenc_si128(d, *R128(&k[3]));
d = _mm_aesenc_si128(d, *R128(&k[4]));
d = _mm_aesenc_si128(d, *R128(&k[5]));
d = _mm_aesenc_si128(d, *R128(&k[6]));
d = _mm_aesenc_si128(d, *R128(&k[7]));
d = _mm_aesenc_si128(d, *R128(&k[8]));
d = _mm_aesenc_si128(d, *R128(&k[9]));
_mm_storeu_si128((R128(out + i * AES_BLOCK_SIZE)), d);
}
}
/**
* @brief aes_pseudo_round that loads data from *in and xors it with *xor first
*
* This function performs the same operations as aes_pseudo_round, but before
* performing the encryption of each 128 bit block from <in>, it xors
* it with the corresponding block from <xor>.
*
* @param in a pointer to nblocks * 128 bits of data to be encrypted
* @param out a pointer to an nblocks * 128 bit buffer where the output will be stored
* @param expandedKey the expanded AES key
* @param xor a pointer to an nblocks * 128 bit buffer that is xored into in before encryption (in is left unmodified)
* @param nblocks the number of 128 blocks of data to be encrypted
*/
STATIC INLINE void aes_pseudo_round_xor(const uint8_t *in, uint8_t *out,
const uint8_t *expandedKey, const uint8_t *xor, int nblocks)
{
__m128i *k = R128(expandedKey);
__m128i *x = R128(xor);
__m128i d;
int i;
for(i = 0; i < nblocks; i++)
{
d = _mm_loadu_si128(R128(in + i * AES_BLOCK_SIZE));
d = _mm_xor_si128(d, *R128(x++));
d = _mm_aesenc_si128(d, *R128(&k[0]));
d = _mm_aesenc_si128(d, *R128(&k[1]));
d = _mm_aesenc_si128(d, *R128(&k[2]));
d = _mm_aesenc_si128(d, *R128(&k[3]));
d = _mm_aesenc_si128(d, *R128(&k[4]));
d = _mm_aesenc_si128(d, *R128(&k[5]));
d = _mm_aesenc_si128(d, *R128(&k[6]));
d = _mm_aesenc_si128(d, *R128(&k[7]));
d = _mm_aesenc_si128(d, *R128(&k[8]));
d = _mm_aesenc_si128(d, *R128(&k[9]));
_mm_storeu_si128((R128(out + i * AES_BLOCK_SIZE)), d);
}
}
#if defined(_MSC_VER) || defined(__MINGW32__)
BOOL SetLockPagesPrivilege(HANDLE hProcess, BOOL bEnable)
{
struct
{
DWORD count;
LUID_AND_ATTRIBUTES privilege[1];
} info;
HANDLE token;
if(!OpenProcessToken(hProcess, TOKEN_ADJUST_PRIVILEGES, &token))
return FALSE;
info.count = 1;
info.privilege[0].Attributes = bEnable ? SE_PRIVILEGE_ENABLED : 0;
if(!LookupPrivilegeValue(NULL, SE_LOCK_MEMORY_NAME, &(info.privilege[0].Luid)))
return FALSE;
if(!AdjustTokenPrivileges(token, FALSE, (PTOKEN_PRIVILEGES) &info, 0, NULL, NULL))
return FALSE;
if (GetLastError() != ERROR_SUCCESS)
return FALSE;
CloseHandle(token);
return TRUE;
}
#endif
/**
* @brief allocate the 2MB scratch buffer using OS support for huge pages, if available
*
* This function tries to allocate the 2MB scratch buffer using a single
* 2MB "huge page" (instead of the usual 4KB page sizes) to reduce TLB misses
* during the random accesses to the scratch buffer. This is one of the
* important speed optimizations needed to make CryptoNight faster.
*
* No parameters. Updates a thread-local pointer, hp_state, to point to
* the allocated buffer.
*/
void slow_hash_allocate_state(void)
{
int state = 0;
if(hp_state != NULL)
return;
#if defined(_MSC_VER) || defined(__MINGW32__)
SetLockPagesPrivilege(GetCurrentProcess(), TRUE);
hp_state = (uint8_t *) VirtualAlloc(hp_state, MEMORY, MEM_LARGE_PAGES |
MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
#else
#if defined(__APPLE__) || defined(__FreeBSD__)
hp_state = mmap(0, MEMORY, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANON, 0, 0);
#else
hp_state = mmap(0, MEMORY, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB, 0, 0);
#endif
if(hp_state == MAP_FAILED)
hp_state = NULL;
#endif
hp_allocated = 1;
if(hp_state == NULL)
{
hp_allocated = 0;
hp_state = (uint8_t *) malloc(MEMORY);
}
}
/**
*@brief frees the state allocated by slow_hash_allocate_state
*/
void slow_hash_free_state(void)
{
if(hp_state == NULL)
return;
if(!hp_allocated)
free(hp_state);
else
{
#if defined(_MSC_VER) || defined(__MINGW32__)
VirtualFree(hp_state, MEMORY, MEM_RELEASE);
#else
munmap(hp_state, MEMORY);
#endif
}
hp_state = NULL;
hp_allocated = 0;
}
/**
* @brief the hash function implementing CryptoNight, used for the Monero proof-of-work
*
* Computes the hash of <data> (which consists of <length> bytes), returning the
* hash in <hash>. The CryptoNight hash operates by first using Keccak 1600,
* the 1600 bit variant of the Keccak hash used in SHA-3, to create a 200 byte
* buffer of pseudorandom data by hashing the supplied data. It then uses this
* random data to fill a large 2MB buffer with pseudorandom data by iteratively
* encrypting it using 10 rounds of AES per entry. After this initialization,
* it executes 500,000 rounds of mixing through the random 2MB buffer using
* AES (typically provided in hardware on modern CPUs) and a 64 bit multiply.
* Finally, it re-mixes this large buffer back into
* the 200 byte "text" buffer, and then hashes this buffer using one of four
* pseudorandomly selected hash functions (Blake, Groestl, JH, or Skein)
* to populate the output.
*
* The 2MB buffer and choice of functions for mixing are designed to make the
* algorithm "CPU-friendly" (and thus, reduce the advantage of GPU, FPGA,
* or ASIC-based implementations): the functions used are fast on modern
* CPUs, and the 2MB size matches the typical amount of L3 cache available per
* core on 2013-era CPUs. When available, this implementation will use hardware
* AES support on x86 CPUs.
*
* A diagram of the inner loop of this function can be found at
* http://www.cs.cmu.edu/~dga/crypto/xmr/cryptonight.png
*
* @param data the data to hash
* @param length the length in bytes of the data
* @param hash a pointer to a buffer in which the final 256 bit hash will be stored
*/
void cn_slow_hash(const void *data, size_t length, char *hash)
{
RDATA_ALIGN16 uint8_t expandedKey[240]; /* These buffers are aligned to use later with SSE functions */
uint8_t text[INIT_SIZE_BYTE];
RDATA_ALIGN16 uint64_t a[2];
RDATA_ALIGN16 uint64_t b[2];
RDATA_ALIGN16 uint64_t c[2];
union cn_slow_hash_state state;
__m128i _a, _b, _c;
uint64_t hi, lo;
size_t i, j;
uint64_t *p = NULL;
oaes_ctx *aes_ctx;
int useAes = check_aes_hw();
static void (*const extra_hashes[4])(const void *, size_t, char *) =
{
hash_extra_blake, hash_extra_groestl, hash_extra_jh, hash_extra_skein
};
// this isn't supposed to happen, but guard against it for now.
if(hp_state == NULL)
slow_hash_allocate_state();
/* CryptoNight Step 1: Use Keccak1600 to initialize the 'state' (and 'text') buffers from the data. */
hash_process(&state.hs, data, length);
memcpy(text, state.init, INIT_SIZE_BYTE);
/* CryptoNight Step 2: Iteratively encrypt the results from Keccak to fill
* the 2MB large random access buffer.
*/
if(useAes)
{
aes_expand_key(state.hs.b, expandedKey);
for(i = 0; i < MEMORY / INIT_SIZE_BYTE; i++)
{
aes_pseudo_round(text, text, expandedKey, INIT_SIZE_BLK);
memcpy(&hp_state[i * INIT_SIZE_BYTE], text, INIT_SIZE_BYTE);
}
}
else
{
aes_ctx = (oaes_ctx *) oaes_alloc();
oaes_key_import_data(aes_ctx, state.hs.b, AES_KEY_SIZE);
for(i = 0; i < MEMORY / INIT_SIZE_BYTE; i++)
{
for(j = 0; j < INIT_SIZE_BLK; j++)
aesb_pseudo_round(&text[AES_BLOCK_SIZE * j], &text[AES_BLOCK_SIZE * j], aes_ctx->key->exp_data);
memcpy(&hp_state[i * INIT_SIZE_BYTE], text, INIT_SIZE_BYTE);
}
}
U64(a)[0] = U64(&state.k[0])[0] ^ U64(&state.k[32])[0];
U64(a)[1] = U64(&state.k[0])[1] ^ U64(&state.k[32])[1];
U64(b)[0] = U64(&state.k[16])[0] ^ U64(&state.k[48])[0];
U64(b)[1] = U64(&state.k[16])[1] ^ U64(&state.k[48])[1];
/* CryptoNight Step 3: Bounce randomly 1 million times through the mixing buffer,
* using 500,000 iterations of the following mixing function. Each execution
* performs two reads and writes from the mixing buffer.
*/
_b = _mm_load_si128(R128(b));
// Two independent versions, one with AES, one without, to ensure that
// the useAes test is only performed once, not every iteration.
if(useAes)
{
for(i = 0; i < ITER / 2; i++)
{
pre_aes();
_c = _mm_aesenc_si128(_c, _a);
post_aes();
}
}
else
{
for(i = 0; i < ITER / 2; i++)
{
pre_aes();
aesb_single_round((uint8_t *) &_c, (uint8_t *) &_c, (uint8_t *) &_a);
post_aes();
}
}
/* CryptoNight Step 4: Sequentially pass through the mixing buffer and use 10 rounds
* of AES encryption to mix the random data back into the 'text' buffer. 'text'
* was originally created with the output of Keccak1600. */
memcpy(text, state.init, INIT_SIZE_BYTE);
if(useAes)
{
aes_expand_key(&state.hs.b[32], expandedKey);
for(i = 0; i < MEMORY / INIT_SIZE_BYTE; i++)
{
// add the xor to the pseudo round
aes_pseudo_round_xor(text, text, expandedKey, &hp_state[i * INIT_SIZE_BYTE], INIT_SIZE_BLK);
}
}
else
{
oaes_key_import_data(aes_ctx, &state.hs.b[32], AES_KEY_SIZE);
for(i = 0; i < MEMORY / INIT_SIZE_BYTE; i++)
{
for(j = 0; j < INIT_SIZE_BLK; j++)
{
xor_blocks(&text[j * AES_BLOCK_SIZE], &hp_state[i * INIT_SIZE_BYTE + j * AES_BLOCK_SIZE]);
aesb_pseudo_round(&text[AES_BLOCK_SIZE * j], &text[AES_BLOCK_SIZE * j], aes_ctx->key->exp_data);
}
}
oaes_free((OAES_CTX **) &aes_ctx);
}
/* CryptoNight Step 5: Apply Keccak to the state again, and then
* use the resulting data to select which of four finalizer
* hash functions to apply to the data (Blake, Groestl, JH, or Skein).
* Use this hash to squeeze the state array down
* to the final 256 bit hash output.
*/
memcpy(state.init, text, INIT_SIZE_BYTE);
hash_permutation(&state.hs);
extra_hashes[state.hs.b[0] & 3](&state, 200, hash);
}