1/*
2 *  RFC 1321 compliant MD5 implementation
3 *
4 *  Based on XySSL: Copyright (C) 2006-2008  Christophe Devine
5 *
6 *  Copyright (C) 2009  Paul Bakker <polarssl_maintainer at polarssl dot org>
7 *
8 *  All rights reserved.
9 *
10 *  Redistribution and use in source and binary forms, with or without
11 *  modification, are permitted provided that the following conditions
12 *  are met:
13 *
14 *    * Redistributions of source code must retain the above copyright
15 *      notice, this list of conditions and the following disclaimer.
16 *    * Redistributions in binary form must reproduce the above copyright
17 *      notice, this list of conditions and the following disclaimer in the
18 *      documentation and/or other materials provided with the distribution.
19 *    * Neither the names of PolarSSL or XySSL nor the names of its contributors
20 *      may be used to endorse or promote products derived from this software
21 *      without specific prior written permission.
22 *
23 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
27 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
30 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35/*
36 *  The MD5 algorithm was designed by Ron Rivest in 1991.
37 *
38 *  http://www.ietf.org/rfc/rfc1321.txt
39 */
40
41#include "netif/ppp/ppp_opts.h"
42#if PPP_SUPPORT && LWIP_INCLUDED_POLARSSL_MD5
43
44#include "netif/ppp/polarssl/md5.h"
45
46#include <string.h>
47
48/*
49 * 32-bit integer manipulation macros (little endian)
50 */
51#ifndef GET_ULONG_LE
52#define GET_ULONG_LE(n,b,i)                             \
53{                                                       \
54    (n) = ( (unsigned long) (b)[(i)    ]       )        \
55        | ( (unsigned long) (b)[(i) + 1] <<  8 )        \
56        | ( (unsigned long) (b)[(i) + 2] << 16 )        \
57        | ( (unsigned long) (b)[(i) + 3] << 24 );       \
58}
59#endif
60
61#ifndef PUT_ULONG_LE
62#define PUT_ULONG_LE(n,b,i)                             \
63{                                                       \
64    (b)[(i)    ] = (unsigned char) ( (n)       );       \
65    (b)[(i) + 1] = (unsigned char) ( (n) >>  8 );       \
66    (b)[(i) + 2] = (unsigned char) ( (n) >> 16 );       \
67    (b)[(i) + 3] = (unsigned char) ( (n) >> 24 );       \
68}
69#endif
70
71/*
72 * MD5 context setup
73 */
74void md5_starts( md5_context *ctx )
75{
76    ctx->total[0] = 0;
77    ctx->total[1] = 0;
78
79    ctx->state[0] = 0x67452301;
80    ctx->state[1] = 0xEFCDAB89;
81    ctx->state[2] = 0x98BADCFE;
82    ctx->state[3] = 0x10325476;
83}
84
85static void md5_process( md5_context *ctx, const unsigned char data[64] )
86{
87    unsigned long X[16], A, B, C, D;
88
89    GET_ULONG_LE( X[ 0], data,  0 );
90    GET_ULONG_LE( X[ 1], data,  4 );
91    GET_ULONG_LE( X[ 2], data,  8 );
92    GET_ULONG_LE( X[ 3], data, 12 );
93    GET_ULONG_LE( X[ 4], data, 16 );
94    GET_ULONG_LE( X[ 5], data, 20 );
95    GET_ULONG_LE( X[ 6], data, 24 );
96    GET_ULONG_LE( X[ 7], data, 28 );
97    GET_ULONG_LE( X[ 8], data, 32 );
98    GET_ULONG_LE( X[ 9], data, 36 );
99    GET_ULONG_LE( X[10], data, 40 );
100    GET_ULONG_LE( X[11], data, 44 );
101    GET_ULONG_LE( X[12], data, 48 );
102    GET_ULONG_LE( X[13], data, 52 );
103    GET_ULONG_LE( X[14], data, 56 );
104    GET_ULONG_LE( X[15], data, 60 );
105
106#define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))
107
108#define P(a,b,c,d,k,s,t)                                \
109{                                                       \
110    a += F(b,c,d) + X[k] + t; a = S(a,s) + b;           \
111}
112
113    A = ctx->state[0];
114    B = ctx->state[1];
115    C = ctx->state[2];
116    D = ctx->state[3];
117
118#define F(x,y,z) (z ^ (x & (y ^ z)))
119
120    P( A, B, C, D,  0,  7, 0xD76AA478 );
121    P( D, A, B, C,  1, 12, 0xE8C7B756 );
122    P( C, D, A, B,  2, 17, 0x242070DB );
123    P( B, C, D, A,  3, 22, 0xC1BDCEEE );
124    P( A, B, C, D,  4,  7, 0xF57C0FAF );
125    P( D, A, B, C,  5, 12, 0x4787C62A );
126    P( C, D, A, B,  6, 17, 0xA8304613 );
127    P( B, C, D, A,  7, 22, 0xFD469501 );
128    P( A, B, C, D,  8,  7, 0x698098D8 );
129    P( D, A, B, C,  9, 12, 0x8B44F7AF );
130    P( C, D, A, B, 10, 17, 0xFFFF5BB1 );
131    P( B, C, D, A, 11, 22, 0x895CD7BE );
132    P( A, B, C, D, 12,  7, 0x6B901122 );
133    P( D, A, B, C, 13, 12, 0xFD987193 );
134    P( C, D, A, B, 14, 17, 0xA679438E );
135    P( B, C, D, A, 15, 22, 0x49B40821 );
136
137#undef F
138
139#define F(x,y,z) (y ^ (z & (x ^ y)))
140
141    P( A, B, C, D,  1,  5, 0xF61E2562 );
142    P( D, A, B, C,  6,  9, 0xC040B340 );
143    P( C, D, A, B, 11, 14, 0x265E5A51 );
144    P( B, C, D, A,  0, 20, 0xE9B6C7AA );
145    P( A, B, C, D,  5,  5, 0xD62F105D );
146    P( D, A, B, C, 10,  9, 0x02441453 );
147    P( C, D, A, B, 15, 14, 0xD8A1E681 );
148    P( B, C, D, A,  4, 20, 0xE7D3FBC8 );
149    P( A, B, C, D,  9,  5, 0x21E1CDE6 );
150    P( D, A, B, C, 14,  9, 0xC33707D6 );
151    P( C, D, A, B,  3, 14, 0xF4D50D87 );
152    P( B, C, D, A,  8, 20, 0x455A14ED );
153    P( A, B, C, D, 13,  5, 0xA9E3E905 );
154    P( D, A, B, C,  2,  9, 0xFCEFA3F8 );
155    P( C, D, A, B,  7, 14, 0x676F02D9 );
156    P( B, C, D, A, 12, 20, 0x8D2A4C8A );
157
158#undef F
159
160#define F(x,y,z) (x ^ y ^ z)
161
162    P( A, B, C, D,  5,  4, 0xFFFA3942 );
163    P( D, A, B, C,  8, 11, 0x8771F681 );
164    P( C, D, A, B, 11, 16, 0x6D9D6122 );
165    P( B, C, D, A, 14, 23, 0xFDE5380C );
166    P( A, B, C, D,  1,  4, 0xA4BEEA44 );
167    P( D, A, B, C,  4, 11, 0x4BDECFA9 );
168    P( C, D, A, B,  7, 16, 0xF6BB4B60 );
169    P( B, C, D, A, 10, 23, 0xBEBFBC70 );
170    P( A, B, C, D, 13,  4, 0x289B7EC6 );
171    P( D, A, B, C,  0, 11, 0xEAA127FA );
172    P( C, D, A, B,  3, 16, 0xD4EF3085 );
173    P( B, C, D, A,  6, 23, 0x04881D05 );
174    P( A, B, C, D,  9,  4, 0xD9D4D039 );
175    P( D, A, B, C, 12, 11, 0xE6DB99E5 );
176    P( C, D, A, B, 15, 16, 0x1FA27CF8 );
177    P( B, C, D, A,  2, 23, 0xC4AC5665 );
178
179#undef F
180
181#define F(x,y,z) (y ^ (x | ~z))
182
183    P( A, B, C, D,  0,  6, 0xF4292244 );
184    P( D, A, B, C,  7, 10, 0x432AFF97 );
185    P( C, D, A, B, 14, 15, 0xAB9423A7 );
186    P( B, C, D, A,  5, 21, 0xFC93A039 );
187    P( A, B, C, D, 12,  6, 0x655B59C3 );
188    P( D, A, B, C,  3, 10, 0x8F0CCC92 );
189    P( C, D, A, B, 10, 15, 0xFFEFF47D );
190    P( B, C, D, A,  1, 21, 0x85845DD1 );
191    P( A, B, C, D,  8,  6, 0x6FA87E4F );
192    P( D, A, B, C, 15, 10, 0xFE2CE6E0 );
193    P( C, D, A, B,  6, 15, 0xA3014314 );
194    P( B, C, D, A, 13, 21, 0x4E0811A1 );
195    P( A, B, C, D,  4,  6, 0xF7537E82 );
196    P( D, A, B, C, 11, 10, 0xBD3AF235 );
197    P( C, D, A, B,  2, 15, 0x2AD7D2BB );
198    P( B, C, D, A,  9, 21, 0xEB86D391 );
199
200#undef F
201
202    ctx->state[0] += A;
203    ctx->state[1] += B;
204    ctx->state[2] += C;
205    ctx->state[3] += D;
206}
207
208/*
209 * MD5 process buffer
210 */
211void md5_update( md5_context *ctx, const unsigned char *input, int ilen )
212{
213    int fill;
214    unsigned long left;
215
216    if( ilen <= 0 )
217        return;
218
219    left = ctx->total[0] & 0x3F;
220    fill = 64 - left;
221
222    ctx->total[0] += ilen;
223    ctx->total[0] &= 0xFFFFFFFF;
224
225    if( ctx->total[0] < (unsigned long) ilen )
226        ctx->total[1]++;
227
228    if( left && ilen >= fill )
229    {
230        MEMCPY( (void *) (ctx->buffer + left),
231                input, fill );
232        md5_process( ctx, ctx->buffer );
233        input += fill;
234        ilen  -= fill;
235        left = 0;
236    }
237
238    while( ilen >= 64 )
239    {
240        md5_process( ctx, input );
241        input += 64;
242        ilen  -= 64;
243    }
244
245    if( ilen > 0 )
246    {
247        MEMCPY( (void *) (ctx->buffer + left),
248                input, ilen );
249    }
250}
251
252static const unsigned char md5_padding[64] =
253{
254 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
255    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
256    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
257    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
258};
259
260/*
261 * MD5 final digest
262 */
263void md5_finish( md5_context *ctx, unsigned char output[16] )
264{
265    unsigned long last, padn;
266    unsigned long high, low;
267    unsigned char msglen[8];
268
269    high = ( ctx->total[0] >> 29 )
270         | ( ctx->total[1] <<  3 );
271    low  = ( ctx->total[0] <<  3 );
272
273    PUT_ULONG_LE( low,  msglen, 0 );
274    PUT_ULONG_LE( high, msglen, 4 );
275
276    last = ctx->total[0] & 0x3F;
277    padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );
278
279    md5_update( ctx, md5_padding, padn );
280    md5_update( ctx, msglen, 8 );
281
282    PUT_ULONG_LE( ctx->state[0], output,  0 );
283    PUT_ULONG_LE( ctx->state[1], output,  4 );
284    PUT_ULONG_LE( ctx->state[2], output,  8 );
285    PUT_ULONG_LE( ctx->state[3], output, 12 );
286}
287
288/*
289 * output = MD5( input buffer )
290 */
291void md5( unsigned char *input, int ilen, unsigned char output[16] )
292{
293    md5_context ctx;
294
295    md5_starts( &ctx );
296    md5_update( &ctx, input, ilen );
297    md5_finish( &ctx, output );
298}
299
300#endif /* PPP_SUPPORT && LWIP_INCLUDED_POLARSSL_MD5 */
301