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/* 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 <drepper@gnu.ai.mit.edu>, 1995.
* heavily modified for GnuPG by Werner Koch <wk@gnupg.org>
*/
/* 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 <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#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 = 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;
_gcry_md_block_write(hd, NULL, 0); /* flush */;
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);
hd->bctx.count = 56;
/* 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);
hd->bctx.count = 64 + 56;
/* 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, 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
_gcry_burn_stack (burn);
}
static byte *
md5_read( void *context )
{
MD5_CONTEXT *hd = (MD5_CONTEXT *) context;
return hd->bctx.buf;
}
static 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 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 },
};
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, NULL,
sizeof (MD5_CONTEXT)
};

File Metadata

Mime Type
text/x-c
Expires
Tue, Jun 3, 5:35 AM (10 h, 22 m)
Storage Engine
local-disk
Storage Format
Raw Data
Storage Handle
1b/28/59af0a917212cf8768bbfa729b30

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