/* vi: set sw=4 ts=4: */ /* * Based on shasum from http://www.netsw.org/crypto/hash/ * Majorly hacked up to use Dr Brian Gladman's sha1 code * * Copyright (C) 2002 Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK. * Copyright (C) 2003 Glenn L. McGrath * Copyright (C) 2003 Erik Andersen * * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. * * --------------------------------------------------------------------------- * Issue Date: 10/11/2002 * * This is a byte oriented version of SHA1 that operates on arrays of bytes * stored in memory. It runs at 22 cycles per byte on a Pentium P4 processor */ #include "libbb.h" #define SHA1_BLOCK_SIZE 64 #define SHA1_DIGEST_SIZE 20 #define SHA1_HASH_SIZE SHA1_DIGEST_SIZE #define SHA2_GOOD 0 #define SHA2_BAD 1 #define rotl32(x,n) (((x) << n) | ((x) >> (32 - n))) #define SHA1_MASK (SHA1_BLOCK_SIZE - 1) /* reverse byte order in 32-bit words */ #define ch(x,y,z) ((z) ^ ((x) & ((y) ^ (z)))) #define parity(x,y,z) ((x) ^ (y) ^ (z)) #define maj(x,y,z) (((x) & (y)) | ((z) & ((x) | (y)))) /* A normal version as set out in the FIPS. This version uses */ /* partial loop unrolling and is optimised for the Pentium 4 */ #define rnd(f,k) \ do { \ t = a; a = rotl32(a,5) + f(b,c,d) + e + k + w[i]; \ e = d; d = c; c = rotl32(b, 30); b = t; \ } while (0) static void sha1_compile(sha1_ctx_t *ctx) { uint32_t w[80], i, a, b, c, d, e, t; /* note that words are compiled from the buffer into 32-bit */ /* words in big-endian order so an order reversal is needed */ /* here on little endian machines */ for (i = 0; i < SHA1_BLOCK_SIZE / 4; ++i) w[i] = htonl(ctx->wbuf[i]); for (i = SHA1_BLOCK_SIZE / 4; i < 80; ++i) w[i] = rotl32(w[i - 3] ^ w[i - 8] ^ w[i - 14] ^ w[i - 16], 1); a = ctx->hash[0]; b = ctx->hash[1]; c = ctx->hash[2]; d = ctx->hash[3]; e = ctx->hash[4]; for (i = 0; i < 20; ++i) { rnd(ch, 0x5a827999); } for (i = 20; i < 40; ++i) { rnd(parity, 0x6ed9eba1); } for (i = 40; i < 60; ++i) { rnd(maj, 0x8f1bbcdc); } for (i = 60; i < 80; ++i) { rnd(parity, 0xca62c1d6); } ctx->hash[0] += a; ctx->hash[1] += b; ctx->hash[2] += c; ctx->hash[3] += d; ctx->hash[4] += e; } void sha1_begin(sha1_ctx_t *ctx) { ctx->count[0] = ctx->count[1] = 0; ctx->hash[0] = 0x67452301; ctx->hash[1] = 0xefcdab89; ctx->hash[2] = 0x98badcfe; ctx->hash[3] = 0x10325476; ctx->hash[4] = 0xc3d2e1f0; } /* SHA1 hash data in an array of bytes into hash buffer and call the */ /* hash_compile function as required. */ void sha1_hash(const void *data, size_t length, sha1_ctx_t *ctx) { uint32_t pos = (uint32_t) (ctx->count[0] & SHA1_MASK); uint32_t freeb = SHA1_BLOCK_SIZE - pos; const unsigned char *sp = data; if ((ctx->count[0] += length) < length) ++(ctx->count[1]); while (length >= freeb) { /* tranfer whole blocks while possible */ memcpy(((unsigned char *) ctx->wbuf) + pos, sp, freeb); sp += freeb; length -= freeb; freeb = SHA1_BLOCK_SIZE; pos = 0; sha1_compile(ctx); } memcpy(((unsigned char *) ctx->wbuf) + pos, sp, length); } void *sha1_end(void *resbuf, sha1_ctx_t *ctx) { /* SHA1 Final padding and digest calculation */ #if BB_BIG_ENDIAN static uint32_t mask[4] = { 0x00000000, 0xff000000, 0xffff0000, 0xffffff00 }; static uint32_t bits[4] = { 0x80000000, 0x00800000, 0x00008000, 0x00000080 }; #else static uint32_t mask[4] = { 0x00000000, 0x000000ff, 0x0000ffff, 0x00ffffff }; static uint32_t bits[4] = { 0x00000080, 0x00008000, 0x00800000, 0x80000000 }; #endif uint8_t *hval = resbuf; uint32_t i, cnt = (uint32_t) (ctx->count[0] & SHA1_MASK); /* mask out the rest of any partial 32-bit word and then set */ /* the next byte to 0x80. On big-endian machines any bytes in */ /* the buffer will be at the top end of 32 bit words, on little */ /* endian machines they will be at the bottom. Hence the AND */ /* and OR masks above are reversed for little endian systems */ ctx->wbuf[cnt >> 2] = (ctx->wbuf[cnt >> 2] & mask[cnt & 3]) | bits[cnt & 3]; /* we need 9 or more empty positions, one for the padding byte */ /* (above) and eight for the length count. If there is not */ /* enough space pad and empty the buffer */ if (cnt > SHA1_BLOCK_SIZE - 9) { if (cnt < 60) ctx->wbuf[15] = 0; sha1_compile(ctx); cnt = 0; } else /* compute a word index for the empty buffer positions */ cnt = (cnt >> 2) + 1; while (cnt < 14) /* and zero pad all but last two positions */ ctx->wbuf[cnt++] = 0; /* assemble the eight byte counter in the buffer in big-endian */ /* format */ ctx->wbuf[14] = htonl((ctx->count[1] << 3) | (ctx->count[0] >> 29)); ctx->wbuf[15] = htonl(ctx->count[0] << 3); sha1_compile(ctx); /* extract the hash value as bytes in case the hash buffer is */ /* misaligned for 32-bit words */ for (i = 0; i < SHA1_DIGEST_SIZE; ++i) hval[i] = (unsigned char) (ctx->hash[i >> 2] >> 8 * (~i & 3)); return resbuf; }