1/*
2 *  RFC 1186/1320 compliant MD4 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 MD4 algorithm was designed by Ron Rivest in 1990.
37 *
38 *  http://www.ietf.org/rfc/rfc1186.txt
39 *  http://www.ietf.org/rfc/rfc1320.txt
40 */
41
42#include "netif/ppp/ppp_opts.h"
43#if PPP_SUPPORT && LWIP_INCLUDED_POLARSSL_MD4
44
45#include "netif/ppp/polarssl/md4.h"
46
47#include <string.h>
48
49/*
50 * 32-bit integer manipulation macros (little endian)
51 */
52#ifndef GET_ULONG_LE
53#define GET_ULONG_LE(n,b,i)                             \
54{                                                       \
55    (n) = ( (unsigned long) (b)[(i)    ]       )        \
56        | ( (unsigned long) (b)[(i) + 1] <<  8 )        \
57        | ( (unsigned long) (b)[(i) + 2] << 16 )        \
58        | ( (unsigned long) (b)[(i) + 3] << 24 );       \
59}
60#endif
61
62#ifndef PUT_ULONG_LE
63#define PUT_ULONG_LE(n,b,i)                             \
64{                                                       \
65    (b)[(i)    ] = (unsigned char) ( (n)       );       \
66    (b)[(i) + 1] = (unsigned char) ( (n) >>  8 );       \
67    (b)[(i) + 2] = (unsigned char) ( (n) >> 16 );       \
68    (b)[(i) + 3] = (unsigned char) ( (n) >> 24 );       \
69}
70#endif
71
72/*
73 * MD4 context setup
74 */
75void md4_starts( md4_context *ctx )
76{
77    ctx->total[0] = 0;
78    ctx->total[1] = 0;
79
80    ctx->state[0] = 0x67452301;
81    ctx->state[1] = 0xEFCDAB89;
82    ctx->state[2] = 0x98BADCFE;
83    ctx->state[3] = 0x10325476;
84}
85
86static void md4_process( md4_context *ctx, const unsigned char data[64] )
87{
88    unsigned long X[16], A, B, C, D;
89
90    GET_ULONG_LE( X[ 0], data,  0 );
91    GET_ULONG_LE( X[ 1], data,  4 );
92    GET_ULONG_LE( X[ 2], data,  8 );
93    GET_ULONG_LE( X[ 3], data, 12 );
94    GET_ULONG_LE( X[ 4], data, 16 );
95    GET_ULONG_LE( X[ 5], data, 20 );
96    GET_ULONG_LE( X[ 6], data, 24 );
97    GET_ULONG_LE( X[ 7], data, 28 );
98    GET_ULONG_LE( X[ 8], data, 32 );
99    GET_ULONG_LE( X[ 9], data, 36 );
100    GET_ULONG_LE( X[10], data, 40 );
101    GET_ULONG_LE( X[11], data, 44 );
102    GET_ULONG_LE( X[12], data, 48 );
103    GET_ULONG_LE( X[13], data, 52 );
104    GET_ULONG_LE( X[14], data, 56 );
105    GET_ULONG_LE( X[15], data, 60 );
106
107#define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))
108
109    A = ctx->state[0];
110    B = ctx->state[1];
111    C = ctx->state[2];
112    D = ctx->state[3];
113
114#define F(x, y, z) ((x & y) | ((~x) & z))
115#define P(a,b,c,d,x,s) { a += F(b,c,d) + x; a = S(a,s); }
116
117    P( A, B, C, D, X[ 0],  3 );
118    P( D, A, B, C, X[ 1],  7 );
119    P( C, D, A, B, X[ 2], 11 );
120    P( B, C, D, A, X[ 3], 19 );
121    P( A, B, C, D, X[ 4],  3 );
122    P( D, A, B, C, X[ 5],  7 );
123    P( C, D, A, B, X[ 6], 11 );
124    P( B, C, D, A, X[ 7], 19 );
125    P( A, B, C, D, X[ 8],  3 );
126    P( D, A, B, C, X[ 9],  7 );
127    P( C, D, A, B, X[10], 11 );
128    P( B, C, D, A, X[11], 19 );
129    P( A, B, C, D, X[12],  3 );
130    P( D, A, B, C, X[13],  7 );
131    P( C, D, A, B, X[14], 11 );
132    P( B, C, D, A, X[15], 19 );
133
134#undef P
135#undef F
136
137#define F(x,y,z) ((x & y) | (x & z) | (y & z))
138#define P(a,b,c,d,x,s) { a += F(b,c,d) + x + 0x5A827999; a = S(a,s); }
139
140    P( A, B, C, D, X[ 0],  3 );
141    P( D, A, B, C, X[ 4],  5 );
142    P( C, D, A, B, X[ 8],  9 );
143    P( B, C, D, A, X[12], 13 );
144    P( A, B, C, D, X[ 1],  3 );
145    P( D, A, B, C, X[ 5],  5 );
146    P( C, D, A, B, X[ 9],  9 );
147    P( B, C, D, A, X[13], 13 );
148    P( A, B, C, D, X[ 2],  3 );
149    P( D, A, B, C, X[ 6],  5 );
150    P( C, D, A, B, X[10],  9 );
151    P( B, C, D, A, X[14], 13 );
152    P( A, B, C, D, X[ 3],  3 );
153    P( D, A, B, C, X[ 7],  5 );
154    P( C, D, A, B, X[11],  9 );
155    P( B, C, D, A, X[15], 13 );
156
157#undef P
158#undef F
159
160#define F(x,y,z) (x ^ y ^ z)
161#define P(a,b,c,d,x,s) { a += F(b,c,d) + x + 0x6ED9EBA1; a = S(a,s); }
162
163    P( A, B, C, D, X[ 0],  3 );
164    P( D, A, B, C, X[ 8],  9 );
165    P( C, D, A, B, X[ 4], 11 );
166    P( B, C, D, A, X[12], 15 );
167    P( A, B, C, D, X[ 2],  3 );
168    P( D, A, B, C, X[10],  9 );
169    P( C, D, A, B, X[ 6], 11 );
170    P( B, C, D, A, X[14], 15 );
171    P( A, B, C, D, X[ 1],  3 );
172    P( D, A, B, C, X[ 9],  9 );
173    P( C, D, A, B, X[ 5], 11 );
174    P( B, C, D, A, X[13], 15 );
175    P( A, B, C, D, X[ 3],  3 );
176    P( D, A, B, C, X[11],  9 );
177    P( C, D, A, B, X[ 7], 11 );
178    P( B, C, D, A, X[15], 15 );
179
180#undef F
181#undef P
182
183    ctx->state[0] += A;
184    ctx->state[1] += B;
185    ctx->state[2] += C;
186    ctx->state[3] += D;
187}
188
189/*
190 * MD4 process buffer
191 */
192void md4_update( md4_context *ctx, const unsigned char *input, int ilen )
193{
194    int fill;
195    unsigned long left;
196
197    if( ilen <= 0 )
198        return;
199
200    left = ctx->total[0] & 0x3F;
201    fill = 64 - left;
202
203    ctx->total[0] += ilen;
204    ctx->total[0] &= 0xFFFFFFFF;
205
206    if( ctx->total[0] < (unsigned long) ilen )
207        ctx->total[1]++;
208
209    if( left && ilen >= fill )
210    {
211        MEMCPY( (void *) (ctx->buffer + left),
212                input, fill );
213        md4_process( ctx, ctx->buffer );
214        input += fill;
215        ilen  -= fill;
216        left = 0;
217    }
218
219    while( ilen >= 64 )
220    {
221        md4_process( ctx, input );
222        input += 64;
223        ilen  -= 64;
224    }
225
226    if( ilen > 0 )
227    {
228        MEMCPY( (void *) (ctx->buffer + left),
229                input, ilen );
230    }
231}
232
233static const unsigned char md4_padding[64] =
234{
235 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
236    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
237    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
238    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
239};
240
241/*
242 * MD4 final digest
243 */
244void md4_finish( md4_context *ctx, unsigned char output[16] )
245{
246    unsigned long last, padn;
247    unsigned long high, low;
248    unsigned char msglen[8];
249
250    high = ( ctx->total[0] >> 29 )
251         | ( ctx->total[1] <<  3 );
252    low  = ( ctx->total[0] <<  3 );
253
254    PUT_ULONG_LE( low,  msglen, 0 );
255    PUT_ULONG_LE( high, msglen, 4 );
256
257    last = ctx->total[0] & 0x3F;
258    padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );
259
260    md4_update( ctx, md4_padding, padn );
261    md4_update( ctx, msglen, 8 );
262
263    PUT_ULONG_LE( ctx->state[0], output,  0 );
264    PUT_ULONG_LE( ctx->state[1], output,  4 );
265    PUT_ULONG_LE( ctx->state[2], output,  8 );
266    PUT_ULONG_LE( ctx->state[3], output, 12 );
267}
268
269/*
270 * output = MD4( input buffer )
271 */
272void md4( unsigned char *input, int ilen, unsigned char output[16] )
273{
274    md4_context ctx;
275
276    md4_starts( &ctx );
277    md4_update( &ctx, input, ilen );
278    md4_finish( &ctx, output );
279}
280
281#endif /* PPP_SUPPORT && LWIP_INCLUDED_POLARSSL_MD4 */
282