PolarSSL v1.2.11
md2.c
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1 /*
2  * RFC 1115/1319 compliant MD2 implementation
3  *
4  * Copyright (C) 2006-2013, Brainspark B.V.
5  *
6  * This file is part of PolarSSL (http://www.polarssl.org)
7  * Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
8  *
9  * All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License along
22  * with this program; if not, write to the Free Software Foundation, Inc.,
23  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24  */
25 /*
26  * The MD2 algorithm was designed by Ron Rivest in 1989.
27  *
28  * http://www.ietf.org/rfc/rfc1115.txt
29  * http://www.ietf.org/rfc/rfc1319.txt
30  */
31 
32 #include "polarssl/config.h"
33 
34 #if defined(POLARSSL_MD2_C)
35 
36 #include "polarssl/md2.h"
37 
38 #if defined(POLARSSL_FS_IO) || defined(POLARSSL_SELF_TEST)
39 #include <stdio.h>
40 #endif
41 
42 /* Implementation that should never be optimized out by the compiler */
43 static void polarssl_zeroize( void *v, size_t n ) {
44  volatile unsigned char *p = v; while( n-- ) *p++ = 0;
45 }
46 
47 #if !defined(POLARSSL_MD2_ALT)
48 
49 static const unsigned char PI_SUBST[256] =
50 {
51  0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36,
52  0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13, 0x62, 0xA7, 0x05, 0xF3,
53  0xC0, 0xC7, 0x73, 0x8C, 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C,
54  0x82, 0xCA, 0x1E, 0x9B, 0x57, 0x3C, 0xFD, 0xD4, 0xE0, 0x16,
55  0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12, 0xBE, 0x4E,
56  0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E,
57  0xBB, 0x2F, 0xEE, 0x7A, 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2,
58  0x07, 0x3F, 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21,
59  0x80, 0x7F, 0x5D, 0x9A, 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E,
60  0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03, 0xFF, 0x19, 0x30, 0xB3,
61  0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A, 0xAC, 0x56,
62  0xAA, 0xC6, 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6,
63  0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1, 0x45, 0x9D,
64  0x70, 0x59, 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65,
65  0xE6, 0x2D, 0xA8, 0x02, 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0,
66  0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69, 0x34, 0x40, 0x7E, 0x0F,
67  0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A, 0xC3, 0x5C,
68  0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26, 0x2C, 0x53, 0x0D, 0x6E,
69  0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81,
70  0x4D, 0x52, 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA,
71  0x24, 0xE1, 0x7B, 0x08, 0x0C, 0xBD, 0xB1, 0x4A, 0x78, 0x88,
72  0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D, 0xE9, 0xCB, 0xD5, 0xFE,
73  0x3B, 0x00, 0x1D, 0x39, 0xF2, 0xEF, 0xB7, 0x0E, 0x66, 0x58,
74  0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
75  0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99,
76  0x8D, 0x33, 0x9F, 0x11, 0x83, 0x14
77 };
78 
79 /*
80  * MD2 context setup
81  */
82 void md2_starts( md2_context *ctx )
83 {
84  memset( ctx->cksum, 0, 16 );
85  memset( ctx->state, 0, 46 );
86  memset( ctx->buffer, 0, 16 );
87  ctx->left = 0;
88 }
89 
90 static void md2_process( md2_context *ctx )
91 {
92  int i, j;
93  unsigned char t = 0;
94 
95  for( i = 0; i < 16; i++ )
96  {
97  ctx->state[i + 16] = ctx->buffer[i];
98  ctx->state[i + 32] =
99  (unsigned char)( ctx->buffer[i] ^ ctx->state[i]);
100  }
101 
102  for( i = 0; i < 18; i++ )
103  {
104  for( j = 0; j < 48; j++ )
105  {
106  ctx->state[j] = (unsigned char)
107  ( ctx->state[j] ^ PI_SUBST[t] );
108  t = ctx->state[j];
109  }
110 
111  t = (unsigned char)( t + i );
112  }
113 
114  t = ctx->cksum[15];
115 
116  for( i = 0; i < 16; i++ )
117  {
118  ctx->cksum[i] = (unsigned char)
119  ( ctx->cksum[i] ^ PI_SUBST[ctx->buffer[i] ^ t] );
120  t = ctx->cksum[i];
121  }
122 }
123 
124 /*
125  * MD2 process buffer
126  */
127 void md2_update( md2_context *ctx, const unsigned char *input, size_t ilen )
128 {
129  size_t fill;
130 
131  while( ilen > 0 )
132  {
133  if( ctx->left + ilen > 16 )
134  fill = 16 - ctx->left;
135  else
136  fill = ilen;
137 
138  memcpy( ctx->buffer + ctx->left, input, fill );
139 
140  ctx->left += fill;
141  input += fill;
142  ilen -= fill;
143 
144  if( ctx->left == 16 )
145  {
146  ctx->left = 0;
147  md2_process( ctx );
148  }
149  }
150 }
151 
152 /*
153  * MD2 final digest
154  */
155 void md2_finish( md2_context *ctx, unsigned char output[16] )
156 {
157  size_t i;
158  unsigned char x;
159 
160  x = (unsigned char)( 16 - ctx->left );
161 
162  for( i = ctx->left; i < 16; i++ )
163  ctx->buffer[i] = x;
164 
165  md2_process( ctx );
166 
167  memcpy( ctx->buffer, ctx->cksum, 16 );
168  md2_process( ctx );
169 
170  memcpy( output, ctx->state, 16 );
171 }
172 
173 #endif /* !POLARSSL_MD2_ALT */
174 
175 /*
176  * output = MD2( input buffer )
177  */
178 void md2( const unsigned char *input, size_t ilen, unsigned char output[16] )
179 {
180  md2_context ctx;
181 
182  md2_starts( &ctx );
183  md2_update( &ctx, input, ilen );
184  md2_finish( &ctx, output );
185 
186  polarssl_zeroize( &ctx, sizeof( md2_context ) );
187 }
188 
189 #if defined(POLARSSL_FS_IO)
190 /*
191  * output = MD2( file contents )
192  */
193 int md2_file( const char *path, unsigned char output[16] )
194 {
195  FILE *f;
196  size_t n;
197  md2_context ctx;
198  unsigned char buf[1024];
199 
200  if( ( f = fopen( path, "rb" ) ) == NULL )
202 
203  md2_starts( &ctx );
204 
205  while( ( n = fread( buf, 1, sizeof( buf ), f ) ) > 0 )
206  md2_update( &ctx, buf, n );
207 
208  md2_finish( &ctx, output );
209 
210  polarssl_zeroize( &ctx, sizeof( md2_context ) );
211 
212  if( ferror( f ) != 0 )
213  {
214  fclose( f );
216  }
217 
218  fclose( f );
219  return( 0 );
220 }
221 #endif /* POLARSSL_FS_IO */
222 
223 /*
224  * MD2 HMAC context setup
225  */
226 void md2_hmac_starts( md2_context *ctx, const unsigned char *key, size_t keylen )
227 {
228  size_t i;
229  unsigned char sum[16];
230 
231  if( keylen > 16 )
232  {
233  md2( key, keylen, sum );
234  keylen = 16;
235  key = sum;
236  }
237 
238  memset( ctx->ipad, 0x36, 16 );
239  memset( ctx->opad, 0x5C, 16 );
240 
241  for( i = 0; i < keylen; i++ )
242  {
243  ctx->ipad[i] = (unsigned char)( ctx->ipad[i] ^ key[i] );
244  ctx->opad[i] = (unsigned char)( ctx->opad[i] ^ key[i] );
245  }
246 
247  md2_starts( ctx );
248  md2_update( ctx, ctx->ipad, 16 );
249 
250  polarssl_zeroize( sum, sizeof( sum ) );
251 }
252 
253 /*
254  * MD2 HMAC process buffer
255  */
256 void md2_hmac_update( md2_context *ctx, const unsigned char *input, size_t ilen )
257 {
258  md2_update( ctx, input, ilen );
259 }
260 
261 /*
262  * MD2 HMAC final digest
263  */
264 void md2_hmac_finish( md2_context *ctx, unsigned char output[16] )
265 {
266  unsigned char tmpbuf[16];
267 
268  md2_finish( ctx, tmpbuf );
269  md2_starts( ctx );
270  md2_update( ctx, ctx->opad, 16 );
271  md2_update( ctx, tmpbuf, 16 );
272  md2_finish( ctx, output );
273 
274  polarssl_zeroize( tmpbuf, sizeof( tmpbuf ) );
275 }
276 
277 /*
278  * MD2 HMAC context reset
279  */
280 void md2_hmac_reset( md2_context *ctx )
281 {
282  md2_starts( ctx );
283  md2_update( ctx, ctx->ipad, 16 );
284 }
285 
286 /*
287  * output = HMAC-MD2( hmac key, input buffer )
288  */
289 void md2_hmac( const unsigned char *key, size_t keylen,
290  const unsigned char *input, size_t ilen,
291  unsigned char output[16] )
292 {
293  md2_context ctx;
294 
295  md2_hmac_starts( &ctx, key, keylen );
296  md2_hmac_update( &ctx, input, ilen );
297  md2_hmac_finish( &ctx, output );
298 
299  polarssl_zeroize( &ctx, sizeof( md2_context ) );
300 }
301 
302 #if defined(POLARSSL_SELF_TEST)
303 
304 /*
305  * RFC 1319 test vectors
306  */
307 static const char md2_test_str[7][81] =
308 {
309  { "" },
310  { "a" },
311  { "abc" },
312  { "message digest" },
313  { "abcdefghijklmnopqrstuvwxyz" },
314  { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" },
315  { "12345678901234567890123456789012345678901234567890123456789012" \
316  "345678901234567890" }
317 };
318 
319 static const unsigned char md2_test_sum[7][16] =
320 {
321  { 0x83, 0x50, 0xE5, 0xA3, 0xE2, 0x4C, 0x15, 0x3D,
322  0xF2, 0x27, 0x5C, 0x9F, 0x80, 0x69, 0x27, 0x73 },
323  { 0x32, 0xEC, 0x01, 0xEC, 0x4A, 0x6D, 0xAC, 0x72,
324  0xC0, 0xAB, 0x96, 0xFB, 0x34, 0xC0, 0xB5, 0xD1 },
325  { 0xDA, 0x85, 0x3B, 0x0D, 0x3F, 0x88, 0xD9, 0x9B,
326  0x30, 0x28, 0x3A, 0x69, 0xE6, 0xDE, 0xD6, 0xBB },
327  { 0xAB, 0x4F, 0x49, 0x6B, 0xFB, 0x2A, 0x53, 0x0B,
328  0x21, 0x9F, 0xF3, 0x30, 0x31, 0xFE, 0x06, 0xB0 },
329  { 0x4E, 0x8D, 0xDF, 0xF3, 0x65, 0x02, 0x92, 0xAB,
330  0x5A, 0x41, 0x08, 0xC3, 0xAA, 0x47, 0x94, 0x0B },
331  { 0xDA, 0x33, 0xDE, 0xF2, 0xA4, 0x2D, 0xF1, 0x39,
332  0x75, 0x35, 0x28, 0x46, 0xC3, 0x03, 0x38, 0xCD },
333  { 0xD5, 0x97, 0x6F, 0x79, 0xD8, 0x3D, 0x3A, 0x0D,
334  0xC9, 0x80, 0x6C, 0x3C, 0x66, 0xF3, 0xEF, 0xD8 }
335 };
336 
337 /*
338  * Checkup routine
339  */
340 int md2_self_test( int verbose )
341 {
342  int i;
343  unsigned char md2sum[16];
344 
345  for( i = 0; i < 7; i++ )
346  {
347  if( verbose != 0 )
348  printf( " MD2 test #%d: ", i + 1 );
349 
350  md2( (unsigned char *) md2_test_str[i],
351  strlen( md2_test_str[i] ), md2sum );
352 
353  if( memcmp( md2sum, md2_test_sum[i], 16 ) != 0 )
354  {
355  if( verbose != 0 )
356  printf( "failed\n" );
357 
358  return( 1 );
359  }
360 
361  if( verbose != 0 )
362  printf( "passed\n" );
363  }
364 
365  if( verbose != 0 )
366  printf( "\n" );
367 
368  return( 0 );
369 }
370 
371 #endif
372 
373 #endif
void md2_update(md2_context *ctx, const unsigned char *input, size_t ilen)
MD2 process buffer.
void md2_hmac_update(md2_context *ctx, const unsigned char *input, size_t ilen)
MD2 HMAC process buffer.
unsigned char cksum[16]
Definition: md2.h:45
unsigned char state[48]
Definition: md2.h:46
Configuration options (set of defines)
void md2(const unsigned char *input, size_t ilen, unsigned char output[16])
Output = MD2( input buffer )
void md2_hmac_finish(md2_context *ctx, unsigned char output[16])
MD2 HMAC final digest.
unsigned char opad[16]
Definition: md2.h:50
int md2_file(const char *path, unsigned char output[16])
Output = MD2( file contents )
size_t left
Definition: md2.h:51
unsigned char buffer[16]
Definition: md2.h:47
#define POLARSSL_ERR_MD2_FILE_IO_ERROR
Read/write error in file.
Definition: md2.h:34
unsigned char ipad[16]
Definition: md2.h:49
int md2_self_test(int verbose)
Checkup routine.
void md2_starts(md2_context *ctx)
MD2 context setup.
void md2_hmac_starts(md2_context *ctx, const unsigned char *key, size_t keylen)
MD2 HMAC context setup.
void md2_hmac(const unsigned char *key, size_t keylen, const unsigned char *input, size_t ilen, unsigned char output[16])
Output = HMAC-MD2( hmac key, input buffer )
void md2_hmac_reset(md2_context *ctx)
MD2 HMAC context reset.
MD2 context structure.
Definition: md2.h:43
void md2_finish(md2_context *ctx, unsigned char output[16])
MD2 final digest.
MD2 message digest algorithm (hash function)