1 /* 2 * mppe.h - Definitions for MPPE 3 * 4 * Copyright (c) 2008 Paul Mackerras. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 18 * 3. The name(s) of the authors of this software must not be used to 19 * endorse or promote products derived from this software without 20 * prior written permission. 21 * 22 * 4. Redistributions of any form whatsoever must retain the following 23 * acknowledgment: 24 * "This product includes software developed by Paul Mackerras 25 * <paulus@samba.org>". 26 * 27 * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO 28 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 29 * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY 30 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 31 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 32 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 33 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 34 */ 35 36 #define MPPE_PAD 4 /* MPPE growth per frame */ 37 #define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ 38 39 /* option bits for ccp_options.mppe */ 40 #define MPPE_OPT_40 0x01 /* 40 bit */ 41 #define MPPE_OPT_128 0x02 /* 128 bit */ 42 #define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ 43 /* unsupported opts */ 44 #define MPPE_OPT_56 0x08 /* 56 bit */ 45 #define MPPE_OPT_MPPC 0x10 /* MPPC compression */ 46 #define MPPE_OPT_D 0x20 /* Unknown */ 47 #define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) 48 #define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ 49 50 /* 51 * This is not nice ... the alternative is a bitfield struct though. 52 * And unfortunately, we cannot share the same bits for the option 53 * names above since C and H are the same bit. We could do a u_int32 54 * but then we have to do a htonl() all the time and/or we still need 55 * to know which octet is which. 56 */ 57 #define MPPE_C_BIT 0x01 /* MPPC */ 58 #define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ 59 #define MPPE_L_BIT 0x20 /* 40-bit */ 60 #define MPPE_S_BIT 0x40 /* 128-bit */ 61 #define MPPE_M_BIT 0x80 /* 56-bit, not supported */ 62 #define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ 63 64 /* Does not include H bit; used for least significant octet only. */ 65 #define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) 66 67 /* Build a CI from mppe opts (see RFC 3078) */ 68 #define MPPE_OPTS_TO_CI(opts, ci) \ 69 do { \ 70 u_char *ptr = ci; /* u_char[4] */ \ 71 \ 72 /* H bit */ \ 73 if (opts & MPPE_OPT_STATEFUL) \ 74 *ptr++ = 0x0; \ 75 else \ 76 *ptr++ = MPPE_H_BIT; \ 77 *ptr++ = 0; \ 78 *ptr++ = 0; \ 79 \ 80 /* S,L bits */ \ 81 *ptr = 0; \ 82 if (opts & MPPE_OPT_128) \ 83 *ptr |= MPPE_S_BIT; \ 84 if (opts & MPPE_OPT_40) \ 85 *ptr |= MPPE_L_BIT; \ 86 /* M,D,C bits not supported */ \ 87 } while (/* CONSTCOND */ 0) 88 89 /* The reverse of the above */ 90 #define MPPE_CI_TO_OPTS(ci, opts) \ 91 do { \ 92 u_char *ptr = ci; /* u_char[4] */ \ 93 \ 94 opts = 0; \ 95 \ 96 /* H bit */ \ 97 if (!(ptr[0] & MPPE_H_BIT)) \ 98 opts |= MPPE_OPT_STATEFUL; \ 99 \ 100 /* S,L bits */ \ 101 if (ptr[3] & MPPE_S_BIT) \ 102 opts |= MPPE_OPT_128; \ 103 if (ptr[3] & MPPE_L_BIT) \ 104 opts |= MPPE_OPT_40; \ 105 \ 106 /* M,D,C bits */ \ 107 if (ptr[3] & MPPE_M_BIT) \ 108 opts |= MPPE_OPT_56; \ 109 if (ptr[3] & MPPE_D_BIT) \ 110 opts |= MPPE_OPT_D; \ 111 if (ptr[3] & MPPE_C_BIT) \ 112 opts |= MPPE_OPT_MPPC; \ 113 \ 114 /* Other bits */ \ 115 if (ptr[0] & ~MPPE_H_BIT) \ 116 opts |= MPPE_OPT_UNKNOWN; \ 117 if (ptr[1] || ptr[2]) \ 118 opts |= MPPE_OPT_UNKNOWN; \ 119 if (ptr[3] & ~MPPE_ALL_BITS) \ 120 opts |= MPPE_OPT_UNKNOWN; \ 121 } while (/* CONSTCOND */ 0) 122