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Diffstat (limited to 'genisoimage/sha512.c')
| -rw-r--r-- | genisoimage/sha512.c | 338 |
1 files changed, 338 insertions, 0 deletions
diff --git a/genisoimage/sha512.c b/genisoimage/sha512.c new file mode 100644 index 0000000..c4987ce --- /dev/null +++ b/genisoimage/sha512.c @@ -0,0 +1,338 @@ +/* Functions to compute SHA512 message digest of files or memory blocks. + according to the definition of SHA512 in FIPS 180-2. + Copyright (C) 2007 Free Software Foundation, Inc. + + Copied here from the GNU C Library version 2.7 on the 10 May 2009 + by Steve McIntyre <93sam@debian.org>. This code was under LGPL v2.1 + in glibc, and that license gives us the option to use and + distribute the code under the terms of the GPL v2 instead. I'm + taking that option. + + 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 2, 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. */ + +/* Written by Ulrich Drepper <drepper@redhat.com>, 2007. */ + +#include <endian.h> +#include <stdlib.h> +#include <string.h> +#include <sys/types.h> + +#include "sha512.h" + +#if __BYTE_ORDER == __LITTLE_ENDIAN +# ifdef _LIBC +# include <byteswap.h> +# define SWAP(n) bswap_64 (n) +# else +# define SWAP(n) \ + (((n) << 56) \ + | (((n) & 0xff00) << 40) \ + | (((n) & 0xff0000) << 24) \ + | (((n) & 0xff000000) << 8) \ + | (((n) >> 8) & 0xff000000) \ + | (((n) >> 24) & 0xff0000) \ + | (((n) >> 40) & 0xff00) \ + | ((n) >> 56)) +# endif +#else +# define SWAP(n) (n) +#endif + + +/* This array contains the bytes used to pad the buffer to the next + 64-byte boundary. (FIPS 180-2:5.1.2) */ +static const unsigned char fillbuf[128] = { 0x80, 0 /* , 0, 0, ... */ }; + + +/* Constants for SHA512 from FIPS 180-2:4.2.3. */ +static const uint64_t K[80] = + { + UINT64_C (0x428a2f98d728ae22), UINT64_C (0x7137449123ef65cd), + UINT64_C (0xb5c0fbcfec4d3b2f), UINT64_C (0xe9b5dba58189dbbc), + UINT64_C (0x3956c25bf348b538), UINT64_C (0x59f111f1b605d019), + UINT64_C (0x923f82a4af194f9b), UINT64_C (0xab1c5ed5da6d8118), + UINT64_C (0xd807aa98a3030242), UINT64_C (0x12835b0145706fbe), + UINT64_C (0x243185be4ee4b28c), UINT64_C (0x550c7dc3d5ffb4e2), + UINT64_C (0x72be5d74f27b896f), UINT64_C (0x80deb1fe3b1696b1), + UINT64_C (0x9bdc06a725c71235), UINT64_C (0xc19bf174cf692694), + UINT64_C (0xe49b69c19ef14ad2), UINT64_C (0xefbe4786384f25e3), + UINT64_C (0x0fc19dc68b8cd5b5), UINT64_C (0x240ca1cc77ac9c65), + UINT64_C (0x2de92c6f592b0275), UINT64_C (0x4a7484aa6ea6e483), + UINT64_C (0x5cb0a9dcbd41fbd4), UINT64_C (0x76f988da831153b5), + UINT64_C (0x983e5152ee66dfab), UINT64_C (0xa831c66d2db43210), + UINT64_C (0xb00327c898fb213f), UINT64_C (0xbf597fc7beef0ee4), + UINT64_C (0xc6e00bf33da88fc2), UINT64_C (0xd5a79147930aa725), + UINT64_C (0x06ca6351e003826f), UINT64_C (0x142929670a0e6e70), + UINT64_C (0x27b70a8546d22ffc), UINT64_C (0x2e1b21385c26c926), + UINT64_C (0x4d2c6dfc5ac42aed), UINT64_C (0x53380d139d95b3df), + UINT64_C (0x650a73548baf63de), UINT64_C (0x766a0abb3c77b2a8), + UINT64_C (0x81c2c92e47edaee6), UINT64_C (0x92722c851482353b), + UINT64_C (0xa2bfe8a14cf10364), UINT64_C (0xa81a664bbc423001), + UINT64_C (0xc24b8b70d0f89791), UINT64_C (0xc76c51a30654be30), + UINT64_C (0xd192e819d6ef5218), UINT64_C (0xd69906245565a910), + UINT64_C (0xf40e35855771202a), UINT64_C (0x106aa07032bbd1b8), + UINT64_C (0x19a4c116b8d2d0c8), UINT64_C (0x1e376c085141ab53), + UINT64_C (0x2748774cdf8eeb99), UINT64_C (0x34b0bcb5e19b48a8), + UINT64_C (0x391c0cb3c5c95a63), UINT64_C (0x4ed8aa4ae3418acb), + UINT64_C (0x5b9cca4f7763e373), UINT64_C (0x682e6ff3d6b2b8a3), + UINT64_C (0x748f82ee5defb2fc), UINT64_C (0x78a5636f43172f60), + UINT64_C (0x84c87814a1f0ab72), UINT64_C (0x8cc702081a6439ec), + UINT64_C (0x90befffa23631e28), UINT64_C (0xa4506cebde82bde9), + UINT64_C (0xbef9a3f7b2c67915), UINT64_C (0xc67178f2e372532b), + UINT64_C (0xca273eceea26619c), UINT64_C (0xd186b8c721c0c207), + UINT64_C (0xeada7dd6cde0eb1e), UINT64_C (0xf57d4f7fee6ed178), + UINT64_C (0x06f067aa72176fba), UINT64_C (0x0a637dc5a2c898a6), + UINT64_C (0x113f9804bef90dae), UINT64_C (0x1b710b35131c471b), + UINT64_C (0x28db77f523047d84), UINT64_C (0x32caab7b40c72493), + UINT64_C (0x3c9ebe0a15c9bebc), UINT64_C (0x431d67c49c100d4c), + UINT64_C (0x4cc5d4becb3e42b6), UINT64_C (0x597f299cfc657e2a), + UINT64_C (0x5fcb6fab3ad6faec), UINT64_C (0x6c44198c4a475817) + }; + + +/* Process LEN bytes of BUFFER, accumulating context into CTX. + It is assumed that LEN % 128 == 0. */ +static void +sha512_process_block (const void *buffer, size_t len, struct sha512_ctx *ctx) +{ + const uint64_t *words = buffer; + size_t nwords = len / sizeof (uint64_t); + uint64_t a = ctx->H[0]; + uint64_t b = ctx->H[1]; + uint64_t c = ctx->H[2]; + uint64_t d = ctx->H[3]; + uint64_t e = ctx->H[4]; + uint64_t f = ctx->H[5]; + uint64_t g = ctx->H[6]; + uint64_t h = ctx->H[7]; + + /* First increment the byte count. FIPS 180-2 specifies the possible + length of the file up to 2^128 bits. Here we only compute the + number of bytes. Do a double word increment. */ + ctx->total[0] += len; + if (ctx->total[0] < len) + ++ctx->total[1]; + + /* Process all bytes in the buffer with 128 bytes in each round of + the loop. */ + while (nwords > 0) + { + uint64_t W[80]; + uint64_t a_save = a; + uint64_t b_save = b; + uint64_t c_save = c; + uint64_t d_save = d; + uint64_t e_save = e; + uint64_t f_save = f; + uint64_t g_save = g; + uint64_t h_save = h; + unsigned int t; + + /* Operators defined in FIPS 180-2:4.1.2. */ +#define Ch(x, y, z) ((x & y) ^ (~x & z)) +#define Maj(x, y, z) ((x & y) ^ (x & z) ^ (y & z)) +#define S0(x) (CYCLIC (x, 28) ^ CYCLIC (x, 34) ^ CYCLIC (x, 39)) +#define S1(x) (CYCLIC (x, 14) ^ CYCLIC (x, 18) ^ CYCLIC (x, 41)) +#define R0(x) (CYCLIC (x, 1) ^ CYCLIC (x, 8) ^ (x >> 7)) +#define R1(x) (CYCLIC (x, 19) ^ CYCLIC (x, 61) ^ (x >> 6)) + + /* It is unfortunate that C does not provide an operator for + cyclic rotation. Hope the C compiler is smart enough. */ +#define CYCLIC(w, s) ((w >> s) | (w << (64 - s))) + + /* Compute the message schedule according to FIPS 180-2:6.3.2 step 2. */ + for (t = 0; t < 16; ++t) + { + W[t] = SWAP (*words); + ++words; + } + for (t = 16; t < 80; ++t) + W[t] = R1 (W[t - 2]) + W[t - 7] + R0 (W[t - 15]) + W[t - 16]; + + /* The actual computation according to FIPS 180-2:6.3.2 step 3. */ + for (t = 0; t < 80; ++t) + { + uint64_t T1 = h + S1 (e) + Ch (e, f, g) + K[t] + W[t]; + uint64_t T2 = S0 (a) + Maj (a, b, c); + h = g; + g = f; + f = e; + e = d + T1; + d = c; + c = b; + b = a; + a = T1 + T2; + } + + /* Add the starting values of the context according to FIPS 180-2:6.3.2 + step 4. */ + a += a_save; + b += b_save; + c += c_save; + d += d_save; + e += e_save; + f += f_save; + g += g_save; + h += h_save; + + /* Prepare for the next round. */ + nwords -= 16; + } + + /* Put checksum in context given as argument. */ + ctx->H[0] = a; + ctx->H[1] = b; + ctx->H[2] = c; + ctx->H[3] = d; + ctx->H[4] = e; + ctx->H[5] = f; + ctx->H[6] = g; + ctx->H[7] = h; +} + + +/* Initialize structure containing state of computation. + (FIPS 180-2:5.3.3) */ +void +sha512_init_ctx (ctx) + struct sha512_ctx *ctx; +{ + ctx->H[0] = UINT64_C (0x6a09e667f3bcc908); + ctx->H[1] = UINT64_C (0xbb67ae8584caa73b); + ctx->H[2] = UINT64_C (0x3c6ef372fe94f82b); + ctx->H[3] = UINT64_C (0xa54ff53a5f1d36f1); + ctx->H[4] = UINT64_C (0x510e527fade682d1); + ctx->H[5] = UINT64_C (0x9b05688c2b3e6c1f); + ctx->H[6] = UINT64_C (0x1f83d9abfb41bd6b); + ctx->H[7] = UINT64_C (0x5be0cd19137e2179); + + ctx->total[0] = ctx->total[1] = 0; + ctx->buflen = 0; +} + + +/* Process the remaining bytes in the internal buffer and the usual + prolog according to the standard and write the result to RESBUF. + + IMPORTANT: On some systems it is required that RESBUF is correctly + aligned for a 32 bits value. */ +void * +sha512_finish_ctx (ctx, resbuf) + struct sha512_ctx *ctx; + void *resbuf; +{ + /* Take yet unprocessed bytes into account. */ + uint64_t bytes = ctx->buflen; + size_t pad; + unsigned int i; + + /* Now count remaining bytes. */ + ctx->total[0] += bytes; + if (ctx->total[0] < bytes) + ++ctx->total[1]; + + pad = bytes >= 112 ? 128 + 112 - bytes : 112 - bytes; + memcpy (&ctx->buffer[bytes], fillbuf, pad); + + /* Put the 128-bit file length in *bits* at the end of the buffer. */ + *(uint64_t *) &ctx->buffer[bytes + pad + 8] = SWAP (ctx->total[0] << 3); + *(uint64_t *) &ctx->buffer[bytes + pad] = SWAP ((ctx->total[1] << 3) | + (ctx->total[0] >> 61)); + + /* Process last bytes. */ + sha512_process_block (ctx->buffer, bytes + pad + 16, ctx); + + /* Put result from CTX in first 64 bytes following RESBUF. */ + for (i = 0; i < 8; ++i) + ((uint64_t *) resbuf)[i] = SWAP (ctx->H[i]); + + return resbuf; +} + + +void +sha512_process_bytes (buffer, len, ctx) + const void *buffer; + size_t len; + struct sha512_ctx *ctx; +{ + /* When we already have some bits in our internal buffer concatenate + both inputs first. */ + if (ctx->buflen != 0) + { + size_t left_over = ctx->buflen; + size_t add = 256 - left_over > len ? len : 256 - left_over; + + memcpy (&ctx->buffer[left_over], buffer, add); + ctx->buflen += add; + + if (ctx->buflen > 128) + { + sha512_process_block (ctx->buffer, ctx->buflen & ~127, ctx); + + ctx->buflen &= 127; + /* The regions in the following copy operation cannot overlap. */ + memcpy (ctx->buffer, &ctx->buffer[(left_over + add) & ~127], + ctx->buflen); + } + + buffer = (const char *) buffer + add; + len -= add; + } + + /* Process available complete blocks. */ + if (len >= 128) + { +#if !_STRING_ARCH_unaligned +/* To check alignment gcc has an appropriate operator. Other + compilers don't. */ +# if __GNUC__ >= 2 +# define UNALIGNED_P(p) (((uintptr_t) p) % __alignof__ (uint64_t) != 0) +# else +# define UNALIGNED_P(p) (((uintptr_t) p) % sizeof (uint64_t) != 0) +# endif + if (UNALIGNED_P (buffer)) + while (len > 128) + { + sha512_process_block (memcpy (ctx->buffer, buffer, 128), 128, + ctx); + buffer = (const char *) buffer + 128; + len -= 128; + } + else +#endif + { + sha512_process_block (buffer, len & ~127, ctx); + buffer = (const char *) buffer + (len & ~127); + len &= 127; + } + } + + /* Move remaining bytes into internal buffer. */ + if (len > 0) + { + size_t left_over = ctx->buflen; + + memcpy (&ctx->buffer[left_over], buffer, len); + left_over += len; + if (left_over >= 128) + { + sha512_process_block (ctx->buffer, 128, ctx); + left_over -= 128; + memcpy (ctx->buffer, &ctx->buffer[128], left_over); + } + ctx->buflen = left_over; + } +} |