xref: /minix3/minix/lib/liblwip/dist/src/netif/ppp/pppcrypt.c (revision 5d5fbe79c1b60734f34c69330aec5496644e8651)
1*5d5fbe79SDavid van Moolenbroek /*
2*5d5fbe79SDavid van Moolenbroek  * pppcrypt.c - PPP/DES linkage for MS-CHAP and EAP SRP-SHA1
3*5d5fbe79SDavid van Moolenbroek  *
4*5d5fbe79SDavid van Moolenbroek  * Extracted from chap_ms.c by James Carlson.
5*5d5fbe79SDavid van Moolenbroek  *
6*5d5fbe79SDavid van Moolenbroek  * Copyright (c) 1995 Eric Rosenquist.  All rights reserved.
7*5d5fbe79SDavid van Moolenbroek  *
8*5d5fbe79SDavid van Moolenbroek  * Redistribution and use in source and binary forms, with or without
9*5d5fbe79SDavid van Moolenbroek  * modification, are permitted provided that the following conditions
10*5d5fbe79SDavid van Moolenbroek  * are met:
11*5d5fbe79SDavid van Moolenbroek  *
12*5d5fbe79SDavid van Moolenbroek  * 1. Redistributions of source code must retain the above copyright
13*5d5fbe79SDavid van Moolenbroek  *    notice, this list of conditions and the following disclaimer.
14*5d5fbe79SDavid van Moolenbroek  *
15*5d5fbe79SDavid van Moolenbroek  * 2. Redistributions in binary form must reproduce the above copyright
16*5d5fbe79SDavid van Moolenbroek  *    notice, this list of conditions and the following disclaimer in
17*5d5fbe79SDavid van Moolenbroek  *    the documentation and/or other materials provided with the
18*5d5fbe79SDavid van Moolenbroek  *    distribution.
19*5d5fbe79SDavid van Moolenbroek  *
20*5d5fbe79SDavid van Moolenbroek  * 3. The name(s) of the authors of this software must not be used to
21*5d5fbe79SDavid van Moolenbroek  *    endorse or promote products derived from this software without
22*5d5fbe79SDavid van Moolenbroek  *    prior written permission.
23*5d5fbe79SDavid van Moolenbroek  *
24*5d5fbe79SDavid van Moolenbroek  * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
25*5d5fbe79SDavid van Moolenbroek  * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
26*5d5fbe79SDavid van Moolenbroek  * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
27*5d5fbe79SDavid van Moolenbroek  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
28*5d5fbe79SDavid van Moolenbroek  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
29*5d5fbe79SDavid van Moolenbroek  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
30*5d5fbe79SDavid van Moolenbroek  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
31*5d5fbe79SDavid van Moolenbroek  */
32*5d5fbe79SDavid van Moolenbroek 
33*5d5fbe79SDavid van Moolenbroek #include "netif/ppp/ppp_opts.h"
34*5d5fbe79SDavid van Moolenbroek #if PPP_SUPPORT && MSCHAP_SUPPORT /* don't build if not necessary */
35*5d5fbe79SDavid van Moolenbroek 
36*5d5fbe79SDavid van Moolenbroek #include "netif/ppp/ppp_impl.h"
37*5d5fbe79SDavid van Moolenbroek 
38*5d5fbe79SDavid van Moolenbroek #include "netif/ppp/pppcrypt.h"
39*5d5fbe79SDavid van Moolenbroek 
40*5d5fbe79SDavid van Moolenbroek 
pppcrypt_get_7bits(u_char * input,int startBit)41*5d5fbe79SDavid van Moolenbroek static u_char pppcrypt_get_7bits(u_char *input, int startBit) {
42*5d5fbe79SDavid van Moolenbroek 	unsigned int word;
43*5d5fbe79SDavid van Moolenbroek 
44*5d5fbe79SDavid van Moolenbroek 	word  = (unsigned)input[startBit / 8] << 8;
45*5d5fbe79SDavid van Moolenbroek 	word |= (unsigned)input[startBit / 8 + 1];
46*5d5fbe79SDavid van Moolenbroek 
47*5d5fbe79SDavid van Moolenbroek 	word >>= 15 - (startBit % 8 + 7);
48*5d5fbe79SDavid van Moolenbroek 
49*5d5fbe79SDavid van Moolenbroek 	return word & 0xFE;
50*5d5fbe79SDavid van Moolenbroek }
51*5d5fbe79SDavid van Moolenbroek 
52*5d5fbe79SDavid van Moolenbroek /* IN  56 bit DES key missing parity bits
53*5d5fbe79SDavid van Moolenbroek  * OUT 64 bit DES key with parity bits added
54*5d5fbe79SDavid van Moolenbroek  */
pppcrypt_56_to_64_bit_key(u_char * key,u_char * des_key)55*5d5fbe79SDavid van Moolenbroek void pppcrypt_56_to_64_bit_key(u_char *key, u_char * des_key) {
56*5d5fbe79SDavid van Moolenbroek 	des_key[0] = pppcrypt_get_7bits(key,  0);
57*5d5fbe79SDavid van Moolenbroek 	des_key[1] = pppcrypt_get_7bits(key,  7);
58*5d5fbe79SDavid van Moolenbroek 	des_key[2] = pppcrypt_get_7bits(key, 14);
59*5d5fbe79SDavid van Moolenbroek 	des_key[3] = pppcrypt_get_7bits(key, 21);
60*5d5fbe79SDavid van Moolenbroek 	des_key[4] = pppcrypt_get_7bits(key, 28);
61*5d5fbe79SDavid van Moolenbroek 	des_key[5] = pppcrypt_get_7bits(key, 35);
62*5d5fbe79SDavid van Moolenbroek 	des_key[6] = pppcrypt_get_7bits(key, 42);
63*5d5fbe79SDavid van Moolenbroek 	des_key[7] = pppcrypt_get_7bits(key, 49);
64*5d5fbe79SDavid van Moolenbroek }
65*5d5fbe79SDavid van Moolenbroek 
66*5d5fbe79SDavid van Moolenbroek #endif /* PPP_SUPPORT && MSCHAP_SUPPORT */
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