/* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ /* This implementation is by Ted Krovetz and was submitted to SUPERCOP and * marked as public domain. It was been altered to allow for non-aligned inputs * and to allow the block counter to be passed in specifically. */ #include #include "chacha20.h" #ifndef CHACHA_RNDS #define CHACHA_RNDS 20 /* 8 (high speed), 20 (conservative), 12 (middle) */ #endif /* Architecture-neutral way to specify 16-byte vector of ints */ typedef unsigned vec __attribute__ ((vector_size (16))); /* This implementation is designed for Neon, SSE and AltiVec machines. The * following specify how to do certain vector operations efficiently on * each architecture, using intrinsics. * This implementation supports parallel processing of multiple blocks, * including potentially using general-purpose registers. */ #if __ARM_NEON__ #include #define GPR_TOO 1 #define VBPI 2 #define ONE (vec)vsetq_lane_u32(1,vdupq_n_u32(0),0) #define LOAD(m) (vec)(*((vec*)(m))) #define STORE(m,r) (*((vec*)(m))) = (r) #define ROTV1(x) (vec)vextq_u32((uint32x4_t)x,(uint32x4_t)x,1) #define ROTV2(x) (vec)vextq_u32((uint32x4_t)x,(uint32x4_t)x,2) #define ROTV3(x) (vec)vextq_u32((uint32x4_t)x,(uint32x4_t)x,3) #define ROTW16(x) (vec)vrev32q_u16((uint16x8_t)x) #if __clang__ #define ROTW7(x) (x << ((vec){ 7, 7, 7, 7})) ^ (x >> ((vec){25,25,25,25})) #define ROTW8(x) (x << ((vec){ 8, 8, 8, 8})) ^ (x >> ((vec){24,24,24,24})) #define ROTW12(x) (x << ((vec){12,12,12,12})) ^ (x >> ((vec){20,20,20,20})) #else #define ROTW7(x) (vec)vsriq_n_u32(vshlq_n_u32((uint32x4_t)x,7),(uint32x4_t)x,25) #define ROTW8(x) (vec)vsriq_n_u32(vshlq_n_u32((uint32x4_t)x,8),(uint32x4_t)x,24) #define ROTW12(x) (vec)vsriq_n_u32(vshlq_n_u32((uint32x4_t)x,12),(uint32x4_t)x,20) #endif #elif __SSE2__ #include #define GPR_TOO 0 #if __clang__ #define VBPI 4 #else #define VBPI 3 #endif #define ONE (vec)_mm_set_epi32(0,0,0,1) #define LOAD(m) (vec)_mm_loadu_si128((__m128i*)(m)) #define STORE(m,r) _mm_storeu_si128((__m128i*)(m), (__m128i) (r)) #define ROTV1(x) (vec)_mm_shuffle_epi32((__m128i)x,_MM_SHUFFLE(0,3,2,1)) #define ROTV2(x) (vec)_mm_shuffle_epi32((__m128i)x,_MM_SHUFFLE(1,0,3,2)) #define ROTV3(x) (vec)_mm_shuffle_epi32((__m128i)x,_MM_SHUFFLE(2,1,0,3)) #define ROTW7(x) (vec)(_mm_slli_epi32((__m128i)x, 7) ^ _mm_srli_epi32((__m128i)x,25)) #define ROTW12(x) (vec)(_mm_slli_epi32((__m128i)x,12) ^ _mm_srli_epi32((__m128i)x,20)) #if __SSSE3__ #include #define ROTW8(x) (vec)_mm_shuffle_epi8((__m128i)x,_mm_set_epi8(14,13,12,15,10,9,8,11,6,5,4,7,2,1,0,3)) #define ROTW16(x) (vec)_mm_shuffle_epi8((__m128i)x,_mm_set_epi8(13,12,15,14,9,8,11,10,5,4,7,6,1,0,3,2)) #else #define ROTW8(x) (vec)(_mm_slli_epi32((__m128i)x, 8) ^ _mm_srli_epi32((__m128i)x,24)) #define ROTW16(x) (vec)(_mm_slli_epi32((__m128i)x,16) ^ _mm_srli_epi32((__m128i)x,16)) #endif #else #error -- Implementation supports only machines with neon or SSE2 #endif #ifndef REVV_BE #define REVV_BE(x) (x) #endif #ifndef REVW_BE #define REVW_BE(x) (x) #endif #define BPI (VBPI + GPR_TOO) /* Blocks computed per loop iteration */ #define DQROUND_VECTORS(a,b,c,d) \ a += b; d ^= a; d = ROTW16(d); \ c += d; b ^= c; b = ROTW12(b); \ a += b; d ^= a; d = ROTW8(d); \ c += d; b ^= c; b = ROTW7(b); \ b = ROTV1(b); c = ROTV2(c); d = ROTV3(d); \ a += b; d ^= a; d = ROTW16(d); \ c += d; b ^= c; b = ROTW12(b); \ a += b; d ^= a; d = ROTW8(d); \ c += d; b ^= c; b = ROTW7(b); \ b = ROTV3(b); c = ROTV2(c); d = ROTV1(d); #define QROUND_WORDS(a,b,c,d) \ a = a+b; d ^= a; d = d<<16 | d>>16; \ c = c+d; b ^= c; b = b<<12 | b>>20; \ a = a+b; d ^= a; d = d<< 8 | d>>24; \ c = c+d; b ^= c; b = b<< 7 | b>>25; #define WRITE_XOR(in, op, d, v0, v1, v2, v3) \ STORE(op + d + 0, LOAD(in + d + 0) ^ REVV_BE(v0)); \ STORE(op + d + 4, LOAD(in + d + 4) ^ REVV_BE(v1)); \ STORE(op + d + 8, LOAD(in + d + 8) ^ REVV_BE(v2)); \ STORE(op + d +12, LOAD(in + d +12) ^ REVV_BE(v3)); void ChaCha20XOR(unsigned char *out, const unsigned char *in, unsigned int inlen, const unsigned char key[32], const unsigned char nonce[12], uint32_t counter) { unsigned iters, i, *op=(unsigned *)out, *ip=(unsigned *)in, *kp; #if defined(__ARM_NEON__) unsigned *np; #endif vec s0, s1, s2, s3; #if !defined(__ARM_NEON__) && !defined(__SSE2__) __attribute__ ((aligned (16))) unsigned key[8], nonce[4]; #endif __attribute__ ((aligned (16))) unsigned chacha_const[] = {0x61707865,0x3320646E,0x79622D32,0x6B206574}; #if defined(__ARM_NEON__) || defined(__SSE2__) kp = (unsigned *)key; #else ((vec *)key)[0] = REVV_BE(((vec *)key)[0]); ((vec *)key)[1] = REVV_BE(((vec *)key)[1]); ((unsigned *)nonce)[0] = REVW_BE(((unsigned *)nonce)[0]); ((unsigned *)nonce)[1] = REVW_BE(((unsigned *)nonce)[1]); ((unsigned *)nonce)[2] = REVW_BE(((unsigned *)nonce)[2]); ((unsigned *)nonce)[3] = REVW_BE(((unsigned *)nonce)[3]); kp = (unsigned *)key; np = (unsigned *)nonce; #endif #if defined(__ARM_NEON__) np = (unsigned*) nonce; #endif s0 = LOAD(chacha_const); s1 = LOAD(&((vec*)kp)[0]); s2 = LOAD(&((vec*)kp)[1]); s3 = (vec) { counter, ((uint32_t*)nonce)[0], ((uint32_t*)nonce)[1], ((uint32_t*)nonce)[2] }; for (iters = 0; iters < inlen/(BPI*64); iters++) { #if GPR_TOO register unsigned x0, x1, x2, x3, x4, x5, x6, x7, x8, x9, x10, x11, x12, x13, x14, x15; #endif #if VBPI > 2 vec v8,v9,v10,v11; #endif #if VBPI > 3 vec v12,v13,v14,v15; #endif vec v0,v1,v2,v3,v4,v5,v6,v7; v4 = v0 = s0; v5 = v1 = s1; v6 = v2 = s2; v3 = s3; v7 = v3 + ONE; #if VBPI > 2 v8 = v4; v9 = v5; v10 = v6; v11 = v7 + ONE; #endif #if VBPI > 3 v12 = v8; v13 = v9; v14 = v10; v15 = v11 + ONE; #endif #if GPR_TOO x0 = chacha_const[0]; x1 = chacha_const[1]; x2 = chacha_const[2]; x3 = chacha_const[3]; x4 = kp[0]; x5 = kp[1]; x6 = kp[2]; x7 = kp[3]; x8 = kp[4]; x9 = kp[5]; x10 = kp[6]; x11 = kp[7]; x12 = counter+BPI*iters+(BPI-1); x13 = np[0]; x14 = np[1]; x15 = np[2]; #endif for (i = CHACHA_RNDS/2; i; i--) { DQROUND_VECTORS(v0,v1,v2,v3) DQROUND_VECTORS(v4,v5,v6,v7) #if VBPI > 2 DQROUND_VECTORS(v8,v9,v10,v11) #endif #if VBPI > 3 DQROUND_VECTORS(v12,v13,v14,v15) #endif #if GPR_TOO QROUND_WORDS( x0, x4, x8,x12) QROUND_WORDS( x1, x5, x9,x13) QROUND_WORDS( x2, x6,x10,x14) QROUND_WORDS( x3, x7,x11,x15) QROUND_WORDS( x0, x5,x10,x15) QROUND_WORDS( x1, x6,x11,x12) QROUND_WORDS( x2, x7, x8,x13) QROUND_WORDS( x3, x4, x9,x14) #endif } WRITE_XOR(ip, op, 0, v0+s0, v1+s1, v2+s2, v3+s3) s3 += ONE; WRITE_XOR(ip, op, 16, v4+s0, v5+s1, v6+s2, v7+s3) s3 += ONE; #if VBPI > 2 WRITE_XOR(ip, op, 32, v8+s0, v9+s1, v10+s2, v11+s3) s3 += ONE; #endif #if VBPI > 3 WRITE_XOR(ip, op, 48, v12+s0, v13+s1, v14+s2, v15+s3) s3 += ONE; #endif ip += VBPI*16; op += VBPI*16; #if GPR_TOO op[0] = REVW_BE(REVW_BE(ip[0]) ^ (x0 + chacha_const[0])); op[1] = REVW_BE(REVW_BE(ip[1]) ^ (x1 + chacha_const[1])); op[2] = REVW_BE(REVW_BE(ip[2]) ^ (x2 + chacha_const[2])); op[3] = REVW_BE(REVW_BE(ip[3]) ^ (x3 + chacha_const[3])); op[4] = REVW_BE(REVW_BE(ip[4]) ^ (x4 + kp[0])); op[5] = REVW_BE(REVW_BE(ip[5]) ^ (x5 + kp[1])); op[6] = REVW_BE(REVW_BE(ip[6]) ^ (x6 + kp[2])); op[7] = REVW_BE(REVW_BE(ip[7]) ^ (x7 + kp[3])); op[8] = REVW_BE(REVW_BE(ip[8]) ^ (x8 + kp[4])); op[9] = REVW_BE(REVW_BE(ip[9]) ^ (x9 + kp[5])); op[10] = REVW_BE(REVW_BE(ip[10]) ^ (x10 + kp[6])); op[11] = REVW_BE(REVW_BE(ip[11]) ^ (x11 + kp[7])); op[12] = REVW_BE(REVW_BE(ip[12]) ^ (x12 + counter+BPI*iters+(BPI-1))); op[13] = REVW_BE(REVW_BE(ip[13]) ^ (x13 + np[0])); op[14] = REVW_BE(REVW_BE(ip[14]) ^ (x14 + np[1])); op[15] = REVW_BE(REVW_BE(ip[15]) ^ (x15 + np[2])); s3 += ONE; ip += 16; op += 16; #endif } for (iters = inlen%(BPI*64)/64; iters != 0; iters--) { vec v0 = s0, v1 = s1, v2 = s2, v3 = s3; for (i = CHACHA_RNDS/2; i; i--) { DQROUND_VECTORS(v0,v1,v2,v3); } WRITE_XOR(ip, op, 0, v0+s0, v1+s1, v2+s2, v3+s3) s3 += ONE; ip += 16; op += 16; } inlen = inlen % 64; if (inlen) { __attribute__ ((aligned (16))) vec buf[4]; vec v0,v1,v2,v3; v0 = s0; v1 = s1; v2 = s2; v3 = s3; for (i = CHACHA_RNDS/2; i; i--) { DQROUND_VECTORS(v0,v1,v2,v3); } if (inlen >= 16) { STORE(op + 0, LOAD(ip + 0) ^ REVV_BE(v0 + s0)); if (inlen >= 32) { STORE(op + 4, LOAD(ip + 4) ^ REVV_BE(v1 + s1)); if (inlen >= 48) { STORE(op + 8, LOAD(ip + 8) ^ REVV_BE(v2 + s2)); buf[3] = REVV_BE(v3 + s3); } else { buf[2] = REVV_BE(v2 + s2); } } else { buf[1] = REVV_BE(v1 + s1); } } else { buf[0] = REVV_BE(v0 + s0); } for (i=inlen & ~15; i