diff options
Diffstat (limited to 'mdfour.c')
| -rw-r--r-- | mdfour.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/mdfour.c b/mdfour.c new file mode 100644 index 0000000..36b55fe --- /dev/null +++ b/mdfour.c @@ -0,0 +1,221 @@ +// Copyright (C) 1997-1998 Andrew Tridgell +// Copyright (C) 2009-2016 Joel Rosdahl +// +// This program is free software; you can redistribute it and/or modify it +// under the terms of the GNU General Public License as published by the Free +// Software Foundation; either version 3 of the License, or (at your option) +// any later version. +// +// This program is distributed in the hope that it will be useful, but WITHOUT +// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or +// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for +// more details. +// +// You should have received a copy of the GNU General Public License along with +// this program; if not, write to the Free Software Foundation, Inc., 51 +// Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +#include "ccache.h" + +// NOTE: This code makes no attempt to be fast! + +static struct mdfour *m; + +#define MASK32 (0xffffffff) + +#define F(X, Y, Z) ((((X)&(Y)) | ((~(X))&(Z)))) +#define G(X, Y, Z) ((((X)&(Y)) | ((X)&(Z)) | ((Y)&(Z)))) +#define H(X, Y, Z) (((X)^(Y)^(Z))) +#define lshift(x, s) (((((x)<<(s))&MASK32) | (((x)>>(32-(s)))&MASK32))) + +#define ROUND1(a, b, c, d, k, s) \ + a = lshift((a + F(b, c, d) + M[k])&MASK32, s) +#define ROUND2(a, b, c, d, k, s) \ + a = lshift((a + G(b, c, d) + M[k] + 0x5A827999)&MASK32, s) +#define ROUND3(a, b, c, d, k, s) \ + a = lshift((a + H(b, c, d) + M[k] + 0x6ED9EBA1)&MASK32, s) + +// This applies md4 to 64 byte chunks. +static void +mdfour64(uint32_t *M) +{ + uint32_t AA, BB, CC, DD; + uint32_t A, B, C, D; + + A = m->A; + B = m->B; + C = m->C; + D = m->D; + AA = A; + BB = B; + CC = C; + DD = D; + + ROUND1(A, B, C, D, 0, 3); ROUND1(D, A, B, C, 1, 7); + ROUND1(C, D, A, B, 2, 11); ROUND1(B, C, D, A, 3, 19); + ROUND1(A, B, C, D, 4, 3); ROUND1(D, A, B, C, 5, 7); + ROUND1(C, D, A, B, 6, 11); ROUND1(B, C, D, A, 7, 19); + ROUND1(A, B, C, D, 8, 3); ROUND1(D, A, B, C, 9, 7); + ROUND1(C, D, A, B, 10, 11); ROUND1(B, C, D, A, 11, 19); + ROUND1(A, B, C, D, 12, 3); ROUND1(D, A, B, C, 13, 7); + ROUND1(C, D, A, B, 14, 11); ROUND1(B, C, D, A, 15, 19); + + + ROUND2(A, B, C, D, 0, 3); ROUND2(D, A, B, C, 4, 5); + ROUND2(C, D, A, B, 8, 9); ROUND2(B, C, D, A, 12, 13); + ROUND2(A, B, C, D, 1, 3); ROUND2(D, A, B, C, 5, 5); + ROUND2(C, D, A, B, 9, 9); ROUND2(B, C, D, A, 13, 13); + ROUND2(A, B, C, D, 2, 3); ROUND2(D, A, B, C, 6, 5); + ROUND2(C, D, A, B, 10, 9); ROUND2(B, C, D, A, 14, 13); + ROUND2(A, B, C, D, 3, 3); ROUND2(D, A, B, C, 7, 5); + ROUND2(C, D, A, B, 11, 9); ROUND2(B, C, D, A, 15, 13); + + ROUND3(A, B, C, D, 0, 3); ROUND3(D, A, B, C, 8, 9); + ROUND3(C, D, A, B, 4, 11); ROUND3(B, C, D, A, 12, 15); + ROUND3(A, B, C, D, 2, 3); ROUND3(D, A, B, C, 10, 9); + ROUND3(C, D, A, B, 6, 11); ROUND3(B, C, D, A, 14, 15); + ROUND3(A, B, C, D, 1, 3); ROUND3(D, A, B, C, 9, 9); + ROUND3(C, D, A, B, 5, 11); ROUND3(B, C, D, A, 13, 15); + ROUND3(A, B, C, D, 3, 3); ROUND3(D, A, B, C, 11, 9); + ROUND3(C, D, A, B, 7, 11); ROUND3(B, C, D, A, 15, 15); + + A += AA; + B += BB; + C += CC; + D += DD; + + A &= MASK32; + B &= MASK32; + C &= MASK32; + D &= MASK32; + + m->A = A; + m->B = B; + m->C = C; + m->D = D; +} + +static void +copy64(uint32_t *M, const unsigned char *in) +{ +#ifdef WORDS_BIGENDIAN + for (int i = 0; i < 16; i++) { + M[i] = (in[i*4+3]<<24) | (in[i*4+2]<<16) | + (in[i*4+1]<<8) | (in[i*4+0]<<0); + } +#else + memcpy(M, in, 16*4); +#endif +} + +static void +copy4(unsigned char *out, uint32_t x) +{ +#ifdef WORDS_BIGENDIAN + out[0] = x&0xFF; + out[1] = (x>>8)&0xFF; + out[2] = (x>>16)&0xFF; + out[3] = (x>>24)&0xFF; +#else + memcpy(out, &x, 4); +#endif +} + +void +mdfour_begin(struct mdfour *md) +{ + md->A = 0x67452301; + md->B = 0xefcdab89; + md->C = 0x98badcfe; + md->D = 0x10325476; + md->totalN = 0; + md->tail_len = 0; + md->finalized = 0; +} + +static +void mdfour_tail(const unsigned char *in, size_t n) +{ + m->totalN += n; + uint32_t b = m->totalN * 8; + unsigned char buf[128] = { 0 }; + uint32_t M[16]; + if (n) { + memcpy(buf, in, n); + } + buf[n] = 0x80; + + if (n <= 55) { + copy4(buf+56, b); + copy64(M, buf); + mdfour64(M); + } else { + copy4(buf+120, b); + copy64(M, buf); + mdfour64(M); + copy64(M, buf+64); + mdfour64(M); + } +} + +void +mdfour_update(struct mdfour *md, const unsigned char *in, size_t n) +{ +#ifdef CCACHE_DEBUG_HASH + if (getenv("CCACHE_DEBUG_HASH")) { + FILE *f = fopen("ccache-debug-hash.bin", "a"); + fwrite(in, 1, n, f); + fclose(f); + } +#endif + + m = md; + + if (!in) { + if (!md->finalized) { + mdfour_tail(md->tail, md->tail_len); + md->finalized = 1; + } + return; + } + + uint32_t M[16]; + if (md->tail_len) { + size_t len = 64 - md->tail_len; + if (len > n) { + len = n; + } + memcpy(md->tail+md->tail_len, in, len); + md->tail_len += len; + n -= len; + in += len; + if (md->tail_len == 64) { + copy64(M, md->tail); + mdfour64(M); + m->totalN += 64; + md->tail_len = 0; + } + } + + while (n >= 64) { + copy64(M, in); + mdfour64(M); + in += 64; + n -= 64; + m->totalN += 64; + } + + if (n) { + memcpy(md->tail, in, n); + md->tail_len = n; + } +} + +void +mdfour_result(struct mdfour *md, unsigned char *out) +{ + copy4(out, md->A); + copy4(out+4, md->B); + copy4(out+8, md->C); + copy4(out+12, md->D); +} |