| /* |
| * pppcrypt.c - PPP/DES linkage for MS-CHAP and EAP SRP-SHA1 |
| * |
| * Extracted from chap_ms.c by James Carlson. |
| * |
| * Copyright (c) 1995 Eric Rosenquist. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The name(s) of the authors of this software must not be used to |
| * endorse or promote products derived from this software without |
| * prior written permission. |
| * |
| * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO |
| * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY |
| * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY |
| * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
| * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN |
| * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING |
| * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| */ |
| |
| #include "netif/ppp/ppp_opts.h" |
| #if PPP_SUPPORT && MSCHAP_SUPPORT /* don't build if not necessary */ |
| |
| #include "netif/ppp/ppp_impl.h" |
| |
| #include "netif/ppp/pppcrypt.h" |
| |
| |
| static u_char pppcrypt_get_7bits(u_char *input, int startBit) { |
| unsigned int word; |
| |
| word = (unsigned)input[startBit / 8] << 8; |
| word |= (unsigned)input[startBit / 8 + 1]; |
| |
| word >>= 15 - (startBit % 8 + 7); |
| |
| return word & 0xFE; |
| } |
| |
| /* IN 56 bit DES key missing parity bits |
| * OUT 64 bit DES key with parity bits added |
| */ |
| void pppcrypt_56_to_64_bit_key(u_char *key, u_char * des_key) { |
| des_key[0] = pppcrypt_get_7bits(key, 0); |
| des_key[1] = pppcrypt_get_7bits(key, 7); |
| des_key[2] = pppcrypt_get_7bits(key, 14); |
| des_key[3] = pppcrypt_get_7bits(key, 21); |
| des_key[4] = pppcrypt_get_7bits(key, 28); |
| des_key[5] = pppcrypt_get_7bits(key, 35); |
| des_key[6] = pppcrypt_get_7bits(key, 42); |
| des_key[7] = pppcrypt_get_7bits(key, 49); |
| } |
| |
| #endif /* PPP_SUPPORT && MSCHAP_SUPPORT */ |