ZeroTierOne/node/Salsa20.cpp
2015-09-30 14:35:05 -07:00

430 lines
14 KiB
C++

/*
* Based on public domain code available at: http://cr.yp.to/snuffle.html
*
* Modifications and C-native SSE macro based SSE implementation by
* Adam Ierymenko <adam.ierymenko@zerotier.com>.
*
* Since the original was public domain, this is too.
*/
#include "Constants.hpp"
#include "Salsa20.hpp"
#define ROTATE(v,c) (((v) << (c)) | ((v) >> (32 - (c))))
#define XOR(v,w) ((v) ^ (w))
#define PLUS(v,w) ((uint32_t)((v) + (w)))
// Set up laod/store macros with appropriate endianness (we don't use these in SSE mode)
#ifndef ZT_SALSA20_SSE
#if __BYTE_ORDER == __LITTLE_ENDIAN
#ifdef ZT_NO_TYPE_PUNNING
// Slower version that does not use type punning
#define U8TO32_LITTLE(p) ( ((uint32_t)(p)[0]) | ((uint32_t)(p)[1] << 8) | ((uint32_t)(p)[2] << 16) | ((uint32_t)(p)[3] << 24) )
static inline void U32TO8_LITTLE(uint8_t *const c,const uint32_t v) { c[0] = (uint8_t)v; c[1] = (uint8_t)(v >> 8); c[2] = (uint8_t)(v >> 16); c[3] = (uint8_t)(v >> 24); }
#else
// Fast version that just does 32-bit load/store
#define U8TO32_LITTLE(p) (*((const uint32_t *)((const void *)(p))))
#define U32TO8_LITTLE(c,v) *((uint32_t *)((void *)(c))) = (v)
#endif // ZT_NO_TYPE_PUNNING
#else // __BYTE_ORDER == __BIG_ENDIAN (we don't support anything else... does MIDDLE_ENDIAN even still exist?)
#ifdef __GNUC__
// Use GNUC builtin bswap macros on big-endian machines if available
#define U8TO32_LITTLE(p) __builtin_bswap32(*((const uint32_t *)((const void *)(p))))
#define U32TO8_LITTLE(c,v) *((uint32_t *)((void *)(c))) = __builtin_bswap32((v))
#else // no __GNUC__
// Otherwise do it the slow, manual way on BE machines
#define U8TO32_LITTLE(p) ( ((uint32_t)(p)[0]) | ((uint32_t)(p)[1] << 8) | ((uint32_t)(p)[2] << 16) | ((uint32_t)(p)[3] << 24) )
static inline void U32TO8_LITTLE(uint8_t *const c,const uint32_t v) { c[0] = (uint8_t)v; c[1] = (uint8_t)(v >> 8); c[2] = (uint8_t)(v >> 16); c[3] = (uint8_t)(v >> 24); }
#endif // __GNUC__ or not
#endif // __BYTE_ORDER little or big?
#endif // !ZT_SALSA20_SSE
// Statically compute and define SSE constants
#ifdef ZT_SALSA20_SSE
class _s20sseconsts
{
public:
_s20sseconsts()
{
maskLo32 = _mm_shuffle_epi32(_mm_cvtsi32_si128(-1), _MM_SHUFFLE(1, 0, 1, 0));
maskHi32 = _mm_slli_epi64(maskLo32, 32);
}
__m128i maskLo32,maskHi32;
};
static const _s20sseconsts _S20SSECONSTANTS;
#endif
namespace ZeroTier {
void Salsa20::init(const void *key,unsigned int kbits,const void *iv,unsigned int rounds)
throw()
{
#ifdef ZT_SALSA20_SSE
const uint32_t *k = (const uint32_t *)key;
_state.i[0] = 0x61707865;
_state.i[3] = 0x6b206574;
_state.i[13] = k[0];
_state.i[10] = k[1];
_state.i[7] = k[2];
_state.i[4] = k[3];
if (kbits == 256) {
k += 4;
_state.i[1] = 0x3320646e;
_state.i[2] = 0x79622d32;
} else {
_state.i[1] = 0x3120646e;
_state.i[2] = 0x79622d36;
}
_state.i[15] = k[0];
_state.i[12] = k[1];
_state.i[9] = k[2];
_state.i[6] = k[3];
_state.i[14] = ((const uint32_t *)iv)[0];
_state.i[11] = ((const uint32_t *)iv)[1];
_state.i[5] = 0;
_state.i[8] = 0;
#else
const char *constants;
const uint8_t *k = (const uint8_t *)key;
_state.i[1] = U8TO32_LITTLE(k + 0);
_state.i[2] = U8TO32_LITTLE(k + 4);
_state.i[3] = U8TO32_LITTLE(k + 8);
_state.i[4] = U8TO32_LITTLE(k + 12);
if (kbits == 256) { /* recommended */
k += 16;
constants = "expand 32-byte k";
} else { /* kbits == 128 */
constants = "expand 16-byte k";
}
_state.i[5] = U8TO32_LITTLE(constants + 4);
_state.i[6] = U8TO32_LITTLE(((const uint8_t *)iv) + 0);
_state.i[7] = U8TO32_LITTLE(((const uint8_t *)iv) + 4);
_state.i[8] = 0;
_state.i[9] = 0;
_state.i[10] = U8TO32_LITTLE(constants + 8);
_state.i[11] = U8TO32_LITTLE(k + 0);
_state.i[12] = U8TO32_LITTLE(k + 4);
_state.i[13] = U8TO32_LITTLE(k + 8);
_state.i[14] = U8TO32_LITTLE(k + 12);
_state.i[15] = U8TO32_LITTLE(constants + 12);
_state.i[0] = U8TO32_LITTLE(constants + 0);
#endif
_roundsDiv4 = rounds / 4;
}
void Salsa20::encrypt(const void *in,void *out,unsigned int bytes)
throw()
{
uint8_t tmp[64];
const uint8_t *m = (const uint8_t *)in;
uint8_t *c = (uint8_t *)out;
uint8_t *ctarget = c;
unsigned int i;
#ifndef ZT_SALSA20_SSE
uint32_t x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15;
uint32_t j0, j1, j2, j3, j4, j5, j6, j7, j8, j9, j10, j11, j12, j13, j14, j15;
#endif
if (!bytes)
return;
#ifndef ZT_SALSA20_SSE
j0 = _state.i[0];
j1 = _state.i[1];
j2 = _state.i[2];
j3 = _state.i[3];
j4 = _state.i[4];
j5 = _state.i[5];
j6 = _state.i[6];
j7 = _state.i[7];
j8 = _state.i[8];
j9 = _state.i[9];
j10 = _state.i[10];
j11 = _state.i[11];
j12 = _state.i[12];
j13 = _state.i[13];
j14 = _state.i[14];
j15 = _state.i[15];
#endif
for (;;) {
if (bytes < 64) {
for (i = 0;i < bytes;++i)
tmp[i] = m[i];
m = tmp;
ctarget = c;
c = tmp;
}
#ifdef ZT_SALSA20_SSE
__m128i X0 = _mm_loadu_si128((const __m128i *)&(_state.v[0]));
__m128i X1 = _mm_loadu_si128((const __m128i *)&(_state.v[1]));
__m128i X2 = _mm_loadu_si128((const __m128i *)&(_state.v[2]));
__m128i X3 = _mm_loadu_si128((const __m128i *)&(_state.v[3]));
__m128i X0s = X0;
__m128i X1s = X1;
__m128i X2s = X2;
__m128i X3s = X3;
for (i=0;i<_roundsDiv4;++i) {
__m128i T = _mm_add_epi32(X0, X3);
X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 7));
X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 25));
T = _mm_add_epi32(X1, X0);
X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
T = _mm_add_epi32(X2, X1);
X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 13));
X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 19));
T = _mm_add_epi32(X3, X2);
X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
X1 = _mm_shuffle_epi32(X1, 0x93);
X2 = _mm_shuffle_epi32(X2, 0x4E);
X3 = _mm_shuffle_epi32(X3, 0x39);
T = _mm_add_epi32(X0, X1);
X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 7));
X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 25));
T = _mm_add_epi32(X3, X0);
X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
T = _mm_add_epi32(X2, X3);
X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 13));
X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 19));
T = _mm_add_epi32(X1, X2);
X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
X1 = _mm_shuffle_epi32(X1, 0x39);
X2 = _mm_shuffle_epi32(X2, 0x4E);
X3 = _mm_shuffle_epi32(X3, 0x93);
// --
T = _mm_add_epi32(X0, X3);
X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 7));
X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 25));
T = _mm_add_epi32(X1, X0);
X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
T = _mm_add_epi32(X2, X1);
X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 13));
X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 19));
T = _mm_add_epi32(X3, X2);
X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
X1 = _mm_shuffle_epi32(X1, 0x93);
X2 = _mm_shuffle_epi32(X2, 0x4E);
X3 = _mm_shuffle_epi32(X3, 0x39);
T = _mm_add_epi32(X0, X1);
X3 = _mm_xor_si128(X3, _mm_slli_epi32(T, 7));
X3 = _mm_xor_si128(X3, _mm_srli_epi32(T, 25));
T = _mm_add_epi32(X3, X0);
X2 = _mm_xor_si128(X2, _mm_slli_epi32(T, 9));
X2 = _mm_xor_si128(X2, _mm_srli_epi32(T, 23));
T = _mm_add_epi32(X2, X3);
X1 = _mm_xor_si128(X1, _mm_slli_epi32(T, 13));
X1 = _mm_xor_si128(X1, _mm_srli_epi32(T, 19));
T = _mm_add_epi32(X1, X2);
X0 = _mm_xor_si128(X0, _mm_slli_epi32(T, 18));
X0 = _mm_xor_si128(X0, _mm_srli_epi32(T, 14));
X1 = _mm_shuffle_epi32(X1, 0x39);
X2 = _mm_shuffle_epi32(X2, 0x4E);
X3 = _mm_shuffle_epi32(X3, 0x93);
}
X0 = _mm_add_epi32(X0s,X0);
X1 = _mm_add_epi32(X1s,X1);
X2 = _mm_add_epi32(X2s,X2);
X3 = _mm_add_epi32(X3s,X3);
{
__m128i k02 = _mm_or_si128(_mm_slli_epi64(X0, 32), _mm_srli_epi64(X3, 32));
k02 = _mm_shuffle_epi32(k02, _MM_SHUFFLE(0, 1, 2, 3));
__m128i k13 = _mm_or_si128(_mm_slli_epi64(X1, 32), _mm_srli_epi64(X0, 32));
k13 = _mm_shuffle_epi32(k13, _MM_SHUFFLE(0, 1, 2, 3));
__m128i k20 = _mm_or_si128(_mm_and_si128(X2, _S20SSECONSTANTS.maskLo32), _mm_and_si128(X1, _S20SSECONSTANTS.maskHi32));
__m128i k31 = _mm_or_si128(_mm_and_si128(X3, _S20SSECONSTANTS.maskLo32), _mm_and_si128(X2, _S20SSECONSTANTS.maskHi32));
const float *const mv = (const float *)m;
float *const cv = (float *)c;
_mm_storeu_ps(cv,_mm_castsi128_ps(_mm_xor_si128(_mm_unpackhi_epi64(k02,k20),_mm_castps_si128(_mm_loadu_ps(mv)))));
_mm_storeu_ps(cv + 4,_mm_castsi128_ps(_mm_xor_si128(_mm_unpackhi_epi64(k13,k31),_mm_castps_si128(_mm_loadu_ps(mv + 4)))));
_mm_storeu_ps(cv + 8,_mm_castsi128_ps(_mm_xor_si128(_mm_unpacklo_epi64(k20,k02),_mm_castps_si128(_mm_loadu_ps(mv + 8)))));
_mm_storeu_ps(cv + 12,_mm_castsi128_ps(_mm_xor_si128(_mm_unpacklo_epi64(k31,k13),_mm_castps_si128(_mm_loadu_ps(mv + 12)))));
}
if (!(++_state.i[8])) {
++_state.i[5]; // state reordered for SSE
/* stopping at 2^70 bytes per nonce is user's responsibility */
}
#else
x0 = j0;
x1 = j1;
x2 = j2;
x3 = j3;
x4 = j4;
x5 = j5;
x6 = j6;
x7 = j7;
x8 = j8;
x9 = j9;
x10 = j10;
x11 = j11;
x12 = j12;
x13 = j13;
x14 = j14;
x15 = j15;
for(i=0;i<_roundsDiv4;++i) {
x4 = XOR( x4,ROTATE(PLUS( x0,x12), 7));
x8 = XOR( x8,ROTATE(PLUS( x4, x0), 9));
x12 = XOR(x12,ROTATE(PLUS( x8, x4),13));
x0 = XOR( x0,ROTATE(PLUS(x12, x8),18));
x9 = XOR( x9,ROTATE(PLUS( x5, x1), 7));
x13 = XOR(x13,ROTATE(PLUS( x9, x5), 9));
x1 = XOR( x1,ROTATE(PLUS(x13, x9),13));
x5 = XOR( x5,ROTATE(PLUS( x1,x13),18));
x14 = XOR(x14,ROTATE(PLUS(x10, x6), 7));
x2 = XOR( x2,ROTATE(PLUS(x14,x10), 9));
x6 = XOR( x6,ROTATE(PLUS( x2,x14),13));
x10 = XOR(x10,ROTATE(PLUS( x6, x2),18));
x3 = XOR( x3,ROTATE(PLUS(x15,x11), 7));
x7 = XOR( x7,ROTATE(PLUS( x3,x15), 9));
x11 = XOR(x11,ROTATE(PLUS( x7, x3),13));
x15 = XOR(x15,ROTATE(PLUS(x11, x7),18));
x1 = XOR( x1,ROTATE(PLUS( x0, x3), 7));
x2 = XOR( x2,ROTATE(PLUS( x1, x0), 9));
x3 = XOR( x3,ROTATE(PLUS( x2, x1),13));
x0 = XOR( x0,ROTATE(PLUS( x3, x2),18));
x6 = XOR( x6,ROTATE(PLUS( x5, x4), 7));
x7 = XOR( x7,ROTATE(PLUS( x6, x5), 9));
x4 = XOR( x4,ROTATE(PLUS( x7, x6),13));
x5 = XOR( x5,ROTATE(PLUS( x4, x7),18));
x11 = XOR(x11,ROTATE(PLUS(x10, x9), 7));
x8 = XOR( x8,ROTATE(PLUS(x11,x10), 9));
x9 = XOR( x9,ROTATE(PLUS( x8,x11),13));
x10 = XOR(x10,ROTATE(PLUS( x9, x8),18));
x12 = XOR(x12,ROTATE(PLUS(x15,x14), 7));
x13 = XOR(x13,ROTATE(PLUS(x12,x15), 9));
x14 = XOR(x14,ROTATE(PLUS(x13,x12),13));
x15 = XOR(x15,ROTATE(PLUS(x14,x13),18));
// --
x4 = XOR( x4,ROTATE(PLUS( x0,x12), 7));
x8 = XOR( x8,ROTATE(PLUS( x4, x0), 9));
x12 = XOR(x12,ROTATE(PLUS( x8, x4),13));
x0 = XOR( x0,ROTATE(PLUS(x12, x8),18));
x9 = XOR( x9,ROTATE(PLUS( x5, x1), 7));
x13 = XOR(x13,ROTATE(PLUS( x9, x5), 9));
x1 = XOR( x1,ROTATE(PLUS(x13, x9),13));
x5 = XOR( x5,ROTATE(PLUS( x1,x13),18));
x14 = XOR(x14,ROTATE(PLUS(x10, x6), 7));
x2 = XOR( x2,ROTATE(PLUS(x14,x10), 9));
x6 = XOR( x6,ROTATE(PLUS( x2,x14),13));
x10 = XOR(x10,ROTATE(PLUS( x6, x2),18));
x3 = XOR( x3,ROTATE(PLUS(x15,x11), 7));
x7 = XOR( x7,ROTATE(PLUS( x3,x15), 9));
x11 = XOR(x11,ROTATE(PLUS( x7, x3),13));
x15 = XOR(x15,ROTATE(PLUS(x11, x7),18));
x1 = XOR( x1,ROTATE(PLUS( x0, x3), 7));
x2 = XOR( x2,ROTATE(PLUS( x1, x0), 9));
x3 = XOR( x3,ROTATE(PLUS( x2, x1),13));
x0 = XOR( x0,ROTATE(PLUS( x3, x2),18));
x6 = XOR( x6,ROTATE(PLUS( x5, x4), 7));
x7 = XOR( x7,ROTATE(PLUS( x6, x5), 9));
x4 = XOR( x4,ROTATE(PLUS( x7, x6),13));
x5 = XOR( x5,ROTATE(PLUS( x4, x7),18));
x11 = XOR(x11,ROTATE(PLUS(x10, x9), 7));
x8 = XOR( x8,ROTATE(PLUS(x11,x10), 9));
x9 = XOR( x9,ROTATE(PLUS( x8,x11),13));
x10 = XOR(x10,ROTATE(PLUS( x9, x8),18));
x12 = XOR(x12,ROTATE(PLUS(x15,x14), 7));
x13 = XOR(x13,ROTATE(PLUS(x12,x15), 9));
x14 = XOR(x14,ROTATE(PLUS(x13,x12),13));
x15 = XOR(x15,ROTATE(PLUS(x14,x13),18));
}
x0 = PLUS(x0,j0);
x1 = PLUS(x1,j1);
x2 = PLUS(x2,j2);
x3 = PLUS(x3,j3);
x4 = PLUS(x4,j4);
x5 = PLUS(x5,j5);
x6 = PLUS(x6,j6);
x7 = PLUS(x7,j7);
x8 = PLUS(x8,j8);
x9 = PLUS(x9,j9);
x10 = PLUS(x10,j10);
x11 = PLUS(x11,j11);
x12 = PLUS(x12,j12);
x13 = PLUS(x13,j13);
x14 = PLUS(x14,j14);
x15 = PLUS(x15,j15);
U32TO8_LITTLE(c + 0,XOR(x0,U8TO32_LITTLE(m + 0)));
U32TO8_LITTLE(c + 4,XOR(x1,U8TO32_LITTLE(m + 4)));
U32TO8_LITTLE(c + 8,XOR(x2,U8TO32_LITTLE(m + 8)));
U32TO8_LITTLE(c + 12,XOR(x3,U8TO32_LITTLE(m + 12)));
U32TO8_LITTLE(c + 16,XOR(x4,U8TO32_LITTLE(m + 16)));
U32TO8_LITTLE(c + 20,XOR(x5,U8TO32_LITTLE(m + 20)));
U32TO8_LITTLE(c + 24,XOR(x6,U8TO32_LITTLE(m + 24)));
U32TO8_LITTLE(c + 28,XOR(x7,U8TO32_LITTLE(m + 28)));
U32TO8_LITTLE(c + 32,XOR(x8,U8TO32_LITTLE(m + 32)));
U32TO8_LITTLE(c + 36,XOR(x9,U8TO32_LITTLE(m + 36)));
U32TO8_LITTLE(c + 40,XOR(x10,U8TO32_LITTLE(m + 40)));
U32TO8_LITTLE(c + 44,XOR(x11,U8TO32_LITTLE(m + 44)));
U32TO8_LITTLE(c + 48,XOR(x12,U8TO32_LITTLE(m + 48)));
U32TO8_LITTLE(c + 52,XOR(x13,U8TO32_LITTLE(m + 52)));
U32TO8_LITTLE(c + 56,XOR(x14,U8TO32_LITTLE(m + 56)));
U32TO8_LITTLE(c + 60,XOR(x15,U8TO32_LITTLE(m + 60)));
if (!(++j8)) {
++j9;
/* stopping at 2^70 bytes per nonce is user's responsibility */
}
#endif
if (bytes <= 64) {
if (bytes < 64) {
for (i = 0;i < bytes;++i)
ctarget[i] = c[i];
}
#ifndef ZT_SALSA20_SSE
_state.i[8] = j8;
_state.i[9] = j9;
#endif
return;
}
bytes -= 64;
c += 64;
m += 64;
}
}
} // namespace ZeroTier