PolarSSL v1.1.5
md2.c
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1 /*
2  * RFC 1115/1319 compliant MD2 implementation
3  *
4  * Copyright (C) 2006-2010, 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 static const unsigned char PI_SUBST[256] =
43 {
44  0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36,
45  0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13, 0x62, 0xA7, 0x05, 0xF3,
46  0xC0, 0xC7, 0x73, 0x8C, 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C,
47  0x82, 0xCA, 0x1E, 0x9B, 0x57, 0x3C, 0xFD, 0xD4, 0xE0, 0x16,
48  0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12, 0xBE, 0x4E,
49  0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E,
50  0xBB, 0x2F, 0xEE, 0x7A, 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2,
51  0x07, 0x3F, 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21,
52  0x80, 0x7F, 0x5D, 0x9A, 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E,
53  0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03, 0xFF, 0x19, 0x30, 0xB3,
54  0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A, 0xAC, 0x56,
55  0xAA, 0xC6, 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6,
56  0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1, 0x45, 0x9D,
57  0x70, 0x59, 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65,
58  0xE6, 0x2D, 0xA8, 0x02, 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0,
59  0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69, 0x34, 0x40, 0x7E, 0x0F,
60  0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A, 0xC3, 0x5C,
61  0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26, 0x2C, 0x53, 0x0D, 0x6E,
62  0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81,
63  0x4D, 0x52, 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA,
64  0x24, 0xE1, 0x7B, 0x08, 0x0C, 0xBD, 0xB1, 0x4A, 0x78, 0x88,
65  0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D, 0xE9, 0xCB, 0xD5, 0xFE,
66  0x3B, 0x00, 0x1D, 0x39, 0xF2, 0xEF, 0xB7, 0x0E, 0x66, 0x58,
67  0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
68  0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99,
69  0x8D, 0x33, 0x9F, 0x11, 0x83, 0x14
70 };
71 
72 /*
73  * MD2 context setup
74  */
75 void md2_starts( md2_context *ctx )
76 {
77  memset( ctx->cksum, 0, 16 );
78  memset( ctx->state, 0, 46 );
79  memset( ctx->buffer, 0, 16 );
80  ctx->left = 0;
81 }
82 
83 static void md2_process( md2_context *ctx )
84 {
85  int i, j;
86  unsigned char t = 0;
87 
88  for( i = 0; i < 16; i++ )
89  {
90  ctx->state[i + 16] = ctx->buffer[i];
91  ctx->state[i + 32] =
92  (unsigned char)( ctx->buffer[i] ^ ctx->state[i]);
93  }
94 
95  for( i = 0; i < 18; i++ )
96  {
97  for( j = 0; j < 48; j++ )
98  {
99  ctx->state[j] = (unsigned char)
100  ( ctx->state[j] ^ PI_SUBST[t] );
101  t = ctx->state[j];
102  }
103 
104  t = (unsigned char)( t + i );
105  }
106 
107  t = ctx->cksum[15];
108 
109  for( i = 0; i < 16; i++ )
110  {
111  ctx->cksum[i] = (unsigned char)
112  ( ctx->cksum[i] ^ PI_SUBST[ctx->buffer[i] ^ t] );
113  t = ctx->cksum[i];
114  }
115 }
116 
117 /*
118  * MD2 process buffer
119  */
120 void md2_update( md2_context *ctx, const unsigned char *input, size_t ilen )
121 {
122  size_t fill;
123 
124  while( ilen > 0 )
125  {
126  if( ctx->left + ilen > 16 )
127  fill = 16 - ctx->left;
128  else
129  fill = ilen;
130 
131  memcpy( ctx->buffer + ctx->left, input, fill );
132 
133  ctx->left += fill;
134  input += fill;
135  ilen -= fill;
136 
137  if( ctx->left == 16 )
138  {
139  ctx->left = 0;
140  md2_process( ctx );
141  }
142  }
143 }
144 
145 /*
146  * MD2 final digest
147  */
148 void md2_finish( md2_context *ctx, unsigned char output[16] )
149 {
150  size_t i;
151  unsigned char x;
152 
153  x = (unsigned char)( 16 - ctx->left );
154 
155  for( i = ctx->left; i < 16; i++ )
156  ctx->buffer[i] = x;
157 
158  md2_process( ctx );
159 
160  memcpy( ctx->buffer, ctx->cksum, 16 );
161  md2_process( ctx );
162 
163  memcpy( output, ctx->state, 16 );
164 }
165 
166 /*
167  * output = MD2( input buffer )
168  */
169 void md2( const unsigned char *input, size_t ilen, unsigned char output[16] )
170 {
171  md2_context ctx;
172 
173  md2_starts( &ctx );
174  md2_update( &ctx, input, ilen );
175  md2_finish( &ctx, output );
176 
177  memset( &ctx, 0, sizeof( md2_context ) );
178 }
179 
180 #if defined(POLARSSL_FS_IO)
181 /*
182  * output = MD2( file contents )
183  */
184 int md2_file( const char *path, unsigned char output[16] )
185 {
186  FILE *f;
187  size_t n;
188  md2_context ctx;
189  unsigned char buf[1024];
190 
191  if( ( f = fopen( path, "rb" ) ) == NULL )
193 
194  md2_starts( &ctx );
195 
196  while( ( n = fread( buf, 1, sizeof( buf ), f ) ) > 0 )
197  md2_update( &ctx, buf, n );
198 
199  md2_finish( &ctx, output );
200 
201  memset( &ctx, 0, sizeof( md2_context ) );
202 
203  if( ferror( f ) != 0 )
204  {
205  fclose( f );
207  }
208 
209  fclose( f );
210  return( 0 );
211 }
212 #endif /* POLARSSL_FS_IO */
213 
214 /*
215  * MD2 HMAC context setup
216  */
217 void md2_hmac_starts( md2_context *ctx, const unsigned char *key, size_t keylen )
218 {
219  size_t i;
220  unsigned char sum[16];
221 
222  if( keylen > 16 )
223  {
224  md2( key, keylen, sum );
225  keylen = 16;
226  key = sum;
227  }
228 
229  memset( ctx->ipad, 0x36, 16 );
230  memset( ctx->opad, 0x5C, 16 );
231 
232  for( i = 0; i < keylen; i++ )
233  {
234  ctx->ipad[i] = (unsigned char)( ctx->ipad[i] ^ key[i] );
235  ctx->opad[i] = (unsigned char)( ctx->opad[i] ^ key[i] );
236  }
237 
238  md2_starts( ctx );
239  md2_update( ctx, ctx->ipad, 16 );
240 
241  memset( sum, 0, sizeof( sum ) );
242 }
243 
244 /*
245  * MD2 HMAC process buffer
246  */
247 void md2_hmac_update( md2_context *ctx, const unsigned char *input, size_t ilen )
248 {
249  md2_update( ctx, input, ilen );
250 }
251 
252 /*
253  * MD2 HMAC final digest
254  */
255 void md2_hmac_finish( md2_context *ctx, unsigned char output[16] )
256 {
257  unsigned char tmpbuf[16];
258 
259  md2_finish( ctx, tmpbuf );
260  md2_starts( ctx );
261  md2_update( ctx, ctx->opad, 16 );
262  md2_update( ctx, tmpbuf, 16 );
263  md2_finish( ctx, output );
264 
265  memset( tmpbuf, 0, sizeof( tmpbuf ) );
266 }
267 
268 /*
269  * MD2 HMAC context reset
270  */
271 void md2_hmac_reset( md2_context *ctx )
272 {
273  md2_starts( ctx );
274  md2_update( ctx, ctx->ipad, 16 );
275 }
276 
277 /*
278  * output = HMAC-MD2( hmac key, input buffer )
279  */
280 void md2_hmac( const unsigned char *key, size_t keylen,
281  const unsigned char *input, size_t ilen,
282  unsigned char output[16] )
283 {
284  md2_context ctx;
285 
286  md2_hmac_starts( &ctx, key, keylen );
287  md2_hmac_update( &ctx, input, ilen );
288  md2_hmac_finish( &ctx, output );
289 
290  memset( &ctx, 0, sizeof( md2_context ) );
291 }
292 
293 #if defined(POLARSSL_SELF_TEST)
294 
295 /*
296  * RFC 1319 test vectors
297  */
298 static const char md2_test_str[7][81] =
299 {
300  { "" },
301  { "a" },
302  { "abc" },
303  { "message digest" },
304  { "abcdefghijklmnopqrstuvwxyz" },
305  { "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" },
306  { "12345678901234567890123456789012345678901234567890123456789012" \
307  "345678901234567890" }
308 };
309 
310 static const unsigned char md2_test_sum[7][16] =
311 {
312  { 0x83, 0x50, 0xE5, 0xA3, 0xE2, 0x4C, 0x15, 0x3D,
313  0xF2, 0x27, 0x5C, 0x9F, 0x80, 0x69, 0x27, 0x73 },
314  { 0x32, 0xEC, 0x01, 0xEC, 0x4A, 0x6D, 0xAC, 0x72,
315  0xC0, 0xAB, 0x96, 0xFB, 0x34, 0xC0, 0xB5, 0xD1 },
316  { 0xDA, 0x85, 0x3B, 0x0D, 0x3F, 0x88, 0xD9, 0x9B,
317  0x30, 0x28, 0x3A, 0x69, 0xE6, 0xDE, 0xD6, 0xBB },
318  { 0xAB, 0x4F, 0x49, 0x6B, 0xFB, 0x2A, 0x53, 0x0B,
319  0x21, 0x9F, 0xF3, 0x30, 0x31, 0xFE, 0x06, 0xB0 },
320  { 0x4E, 0x8D, 0xDF, 0xF3, 0x65, 0x02, 0x92, 0xAB,
321  0x5A, 0x41, 0x08, 0xC3, 0xAA, 0x47, 0x94, 0x0B },
322  { 0xDA, 0x33, 0xDE, 0xF2, 0xA4, 0x2D, 0xF1, 0x39,
323  0x75, 0x35, 0x28, 0x46, 0xC3, 0x03, 0x38, 0xCD },
324  { 0xD5, 0x97, 0x6F, 0x79, 0xD8, 0x3D, 0x3A, 0x0D,
325  0xC9, 0x80, 0x6C, 0x3C, 0x66, 0xF3, 0xEF, 0xD8 }
326 };
327 
328 /*
329  * Checkup routine
330  */
331 int md2_self_test( int verbose )
332 {
333  int i;
334  unsigned char md2sum[16];
335 
336  for( i = 0; i < 7; i++ )
337  {
338  if( verbose != 0 )
339  printf( " MD2 test #%d: ", i + 1 );
340 
341  md2( (unsigned char *) md2_test_str[i],
342  strlen( md2_test_str[i] ), md2sum );
343 
344  if( memcmp( md2sum, md2_test_sum[i], 16 ) != 0 )
345  {
346  if( verbose != 0 )
347  printf( "failed\n" );
348 
349  return( 1 );
350  }
351 
352  if( verbose != 0 )
353  printf( "passed\n" );
354  }
355 
356  if( verbose != 0 )
357  printf( "\n" );
358 
359  return( 0 );
360 }
361 
362 #endif
363 
364 #endif