/* md5.c - MD5 Message-Digest Algorithm * Copyright (C) 1995,1996,1998,1999,2001,2002, * 2003 Free Software Foundation, Inc. * * This file is part of Libgcrypt. * * Libgcrypt is free software; you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * Libgcrypt 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 Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA * * According to the definition of MD5 in RFC 1321 from April 1992. * NOTE: This is *not* the same file as the one from glibc. * Written by Ulrich Drepper , 1995. * heavily modified for GnuPG by Werner Koch */ /* Test values: * "" D4 1D 8C D9 8F 00 B2 04 E9 80 09 98 EC F8 42 7E * "a" 0C C1 75 B9 C0 F1 B6 A8 31 C3 99 E2 69 77 26 61 * "abc 90 01 50 98 3C D2 4F B0 D6 96 3F 7D 28 E1 7F 72 * "message digest" F9 6B 69 7D 7C B7 93 8D 52 5A 2F 31 AA F1 61 D0 */ #include #include #include #include #include "g10lib.h" #include "cipher.h" #include "bithelp.h" #include "bufhelp.h" #include "hash-common.h" typedef struct { gcry_md_block_ctx_t bctx; u32 A,B,C,D; /* chaining variables */ } MD5_CONTEXT; static unsigned int transform ( void *ctx, const unsigned char *data, size_t datalen ); static void md5_init( void *context, unsigned int flags) { MD5_CONTEXT *ctx = context; (void)flags; ctx->A = 0x67452301; ctx->B = 0xefcdab89; ctx->C = 0x98badcfe; ctx->D = 0x10325476; ctx->bctx.nblocks = 0; ctx->bctx.nblocks_high = 0; ctx->bctx.count = 0; ctx->bctx.blocksize_shift = _gcry_ctz(64); ctx->bctx.bwrite = transform; } /* These are the four functions used in the four steps of the MD5 algorithm and defined in the RFC 1321. The first function is a little bit optimized (as found in Colin Plumbs public domain implementation). */ /* #define FF(b, c, d) ((b & c) | (~b & d)) */ #define FF(b, c, d) (d ^ (b & (c ^ d))) #define FG(b, c, d) FF (d, b, c) #define FH(b, c, d) (b ^ c ^ d) #define FI(b, c, d) (c ^ (b | ~d)) /**************** * transform 64 bytes */ static unsigned int transform_blk ( void *c, const unsigned char *data ) { MD5_CONTEXT *ctx = c; u32 correct_words[16]; register u32 A = ctx->A; register u32 B = ctx->B; register u32 C = ctx->C; register u32 D = ctx->D; u32 *cwp = correct_words; int i; for ( i = 0; i < 16; i++ ) correct_words[i] = buf_get_le32(data + i * 4); #define OP(a, b, c, d, s, T) \ do \ { \ a += FF (b, c, d) + (*cwp++) + T; \ a = rol(a, s); \ a += b; \ } \ while (0) /* Before we start, one word about the strange constants. They are defined in RFC 1321 as T[i] = (int) (4294967296.0 * fabs (sin (i))), i=1..64 */ /* Round 1. */ OP (A, B, C, D, 7, 0xd76aa478); OP (D, A, B, C, 12, 0xe8c7b756); OP (C, D, A, B, 17, 0x242070db); OP (B, C, D, A, 22, 0xc1bdceee); OP (A, B, C, D, 7, 0xf57c0faf); OP (D, A, B, C, 12, 0x4787c62a); OP (C, D, A, B, 17, 0xa8304613); OP (B, C, D, A, 22, 0xfd469501); OP (A, B, C, D, 7, 0x698098d8); OP (D, A, B, C, 12, 0x8b44f7af); OP (C, D, A, B, 17, 0xffff5bb1); OP (B, C, D, A, 22, 0x895cd7be); OP (A, B, C, D, 7, 0x6b901122); OP (D, A, B, C, 12, 0xfd987193); OP (C, D, A, B, 17, 0xa679438e); OP (B, C, D, A, 22, 0x49b40821); #undef OP #define OP(f, a, b, c, d, k, s, T) \ do \ { \ a += f (b, c, d) + correct_words[k] + T; \ a = rol(a, s); \ a += b; \ } \ while (0) /* Round 2. */ OP (FG, A, B, C, D, 1, 5, 0xf61e2562); OP (FG, D, A, B, C, 6, 9, 0xc040b340); OP (FG, C, D, A, B, 11, 14, 0x265e5a51); OP (FG, B, C, D, A, 0, 20, 0xe9b6c7aa); OP (FG, A, B, C, D, 5, 5, 0xd62f105d); OP (FG, D, A, B, C, 10, 9, 0x02441453); OP (FG, C, D, A, B, 15, 14, 0xd8a1e681); OP (FG, B, C, D, A, 4, 20, 0xe7d3fbc8); OP (FG, A, B, C, D, 9, 5, 0x21e1cde6); OP (FG, D, A, B, C, 14, 9, 0xc33707d6); OP (FG, C, D, A, B, 3, 14, 0xf4d50d87); OP (FG, B, C, D, A, 8, 20, 0x455a14ed); OP (FG, A, B, C, D, 13, 5, 0xa9e3e905); OP (FG, D, A, B, C, 2, 9, 0xfcefa3f8); OP (FG, C, D, A, B, 7, 14, 0x676f02d9); OP (FG, B, C, D, A, 12, 20, 0x8d2a4c8a); /* Round 3. */ OP (FH, A, B, C, D, 5, 4, 0xfffa3942); OP (FH, D, A, B, C, 8, 11, 0x8771f681); OP (FH, C, D, A, B, 11, 16, 0x6d9d6122); OP (FH, B, C, D, A, 14, 23, 0xfde5380c); OP (FH, A, B, C, D, 1, 4, 0xa4beea44); OP (FH, D, A, B, C, 4, 11, 0x4bdecfa9); OP (FH, C, D, A, B, 7, 16, 0xf6bb4b60); OP (FH, B, C, D, A, 10, 23, 0xbebfbc70); OP (FH, A, B, C, D, 13, 4, 0x289b7ec6); OP (FH, D, A, B, C, 0, 11, 0xeaa127fa); OP (FH, C, D, A, B, 3, 16, 0xd4ef3085); OP (FH, B, C, D, A, 6, 23, 0x04881d05); OP (FH, A, B, C, D, 9, 4, 0xd9d4d039); OP (FH, D, A, B, C, 12, 11, 0xe6db99e5); OP (FH, C, D, A, B, 15, 16, 0x1fa27cf8); OP (FH, B, C, D, A, 2, 23, 0xc4ac5665); /* Round 4. */ OP (FI, A, B, C, D, 0, 6, 0xf4292244); OP (FI, D, A, B, C, 7, 10, 0x432aff97); OP (FI, C, D, A, B, 14, 15, 0xab9423a7); OP (FI, B, C, D, A, 5, 21, 0xfc93a039); OP (FI, A, B, C, D, 12, 6, 0x655b59c3); OP (FI, D, A, B, C, 3, 10, 0x8f0ccc92); OP (FI, C, D, A, B, 10, 15, 0xffeff47d); OP (FI, B, C, D, A, 1, 21, 0x85845dd1); OP (FI, A, B, C, D, 8, 6, 0x6fa87e4f); OP (FI, D, A, B, C, 15, 10, 0xfe2ce6e0); OP (FI, C, D, A, B, 6, 15, 0xa3014314); OP (FI, B, C, D, A, 13, 21, 0x4e0811a1); OP (FI, A, B, C, D, 4, 6, 0xf7537e82); OP (FI, D, A, B, C, 11, 10, 0xbd3af235); OP (FI, C, D, A, B, 2, 15, 0x2ad7d2bb); OP (FI, B, C, D, A, 9, 21, 0xeb86d391); /* Put checksum in context given as argument. */ ctx->A += A; ctx->B += B; ctx->C += C; ctx->D += D; return /*burn_stack*/ 80+6*sizeof(void*); } static unsigned int transform ( void *c, const unsigned char *data, size_t nblks ) { unsigned int burn; do { burn = transform_blk (c, data); data += 64; } while (--nblks); return burn; } /* The routine final terminates the message-digest computation and * ends with the desired message digest in mdContext->digest[0...15]. * The handle is prepared for a new MD5 cycle. * Returns 16 bytes representing the digest. */ static void md5_final( void *context) { MD5_CONTEXT *hd = context; u32 t, th, msb, lsb; byte *p; unsigned int burn; t = hd->bctx.nblocks; if (sizeof t == sizeof hd->bctx.nblocks) th = hd->bctx.nblocks_high; else th = hd->bctx.nblocks >> 32; /* multiply by 64 to make a byte count */ lsb = t << 6; msb = (th << 6) | (t >> 26); /* add the count */ t = lsb; if( (lsb += hd->bctx.count) < t ) msb++; /* multiply by 8 to make a bit count */ t = lsb; lsb <<= 3; msb <<= 3; msb |= t >> 29; if (hd->bctx.count < 56) /* enough room */ { hd->bctx.buf[hd->bctx.count++] = 0x80; /* pad */ if (hd->bctx.count < 56) memset (&hd->bctx.buf[hd->bctx.count], 0, 56 - hd->bctx.count); /* append the 64 bit count */ buf_put_le32(hd->bctx.buf + 56, lsb); buf_put_le32(hd->bctx.buf + 60, msb); burn = transform (hd, hd->bctx.buf, 1); } else /* need one extra block */ { hd->bctx.buf[hd->bctx.count++] = 0x80; /* pad character */ /* fill pad and next block with zeroes */ memset (&hd->bctx.buf[hd->bctx.count], 0, 64 - hd->bctx.count + 56); /* append the 64 bit count */ buf_put_le32(hd->bctx.buf + 64 + 56, lsb); buf_put_le32(hd->bctx.buf + 64 + 60, msb); burn = transform (hd, hd->bctx.buf, 2); } p = hd->bctx.buf; #define X(a) do { buf_put_le32(p, hd->a); p += 4; } while(0) X(A); X(B); X(C); X(D); #undef X hd->bctx.count = 0; _gcry_burn_stack (burn); } static byte * md5_read( void *context ) { MD5_CONTEXT *hd = (MD5_CONTEXT *) context; return hd->bctx.buf; } static const byte asn[18] = /* Object ID is 1.2.840.113549.2.5 */ { 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86,0x48, 0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10 }; static const gcry_md_oid_spec_t oid_spec_md5[] = { /* iso.member-body.us.rsadsi.pkcs.pkcs-1.4 (md5WithRSAEncryption) */ { "1.2.840.113549.1.1.4" }, /* RSADSI digestAlgorithm MD5 */ { "1.2.840.113549.2.5" }, { NULL }, }; const gcry_md_spec_t _gcry_digest_spec_md5 = { GCRY_MD_MD5, {0, 0}, "MD5", asn, DIM (asn), oid_spec_md5, 16, md5_init, _gcry_md_block_write, md5_final, md5_read, NULL, NULL, sizeof (MD5_CONTEXT) };