| Matt Domsch | b3f9b92 | 2005-11-08 09:40:47 -0800 | [diff] [blame] | 1 | #define MPPE_PAD 4 /* MPPE growth per frame */ |
| 2 | #define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ |
| 3 | |
| 4 | /* option bits for ccp_options.mppe */ |
| 5 | #define MPPE_OPT_40 0x01 /* 40 bit */ |
| 6 | #define MPPE_OPT_128 0x02 /* 128 bit */ |
| 7 | #define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ |
| 8 | /* unsupported opts */ |
| 9 | #define MPPE_OPT_56 0x08 /* 56 bit */ |
| 10 | #define MPPE_OPT_MPPC 0x10 /* MPPC compression */ |
| 11 | #define MPPE_OPT_D 0x20 /* Unknown */ |
| 12 | #define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) |
| 13 | #define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ |
| 14 | |
| 15 | /* |
| 16 | * This is not nice ... the alternative is a bitfield struct though. |
| 17 | * And unfortunately, we cannot share the same bits for the option |
| 18 | * names above since C and H are the same bit. We could do a u_int32 |
| 19 | * but then we have to do a htonl() all the time and/or we still need |
| 20 | * to know which octet is which. |
| 21 | */ |
| 22 | #define MPPE_C_BIT 0x01 /* MPPC */ |
| 23 | #define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ |
| 24 | #define MPPE_L_BIT 0x20 /* 40-bit */ |
| 25 | #define MPPE_S_BIT 0x40 /* 128-bit */ |
| 26 | #define MPPE_M_BIT 0x80 /* 56-bit, not supported */ |
| 27 | #define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ |
| 28 | |
| 29 | /* Does not include H bit; used for least significant octet only. */ |
| 30 | #define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) |
| 31 | |
| 32 | /* Build a CI from mppe opts (see RFC 3078) */ |
| 33 | #define MPPE_OPTS_TO_CI(opts, ci) \ |
| 34 | do { \ |
| 35 | u_char *ptr = ci; /* u_char[4] */ \ |
| 36 | \ |
| 37 | /* H bit */ \ |
| 38 | if (opts & MPPE_OPT_STATEFUL) \ |
| 39 | *ptr++ = 0x0; \ |
| 40 | else \ |
| 41 | *ptr++ = MPPE_H_BIT; \ |
| 42 | *ptr++ = 0; \ |
| 43 | *ptr++ = 0; \ |
| 44 | \ |
| 45 | /* S,L bits */ \ |
| 46 | *ptr = 0; \ |
| 47 | if (opts & MPPE_OPT_128) \ |
| 48 | *ptr |= MPPE_S_BIT; \ |
| 49 | if (opts & MPPE_OPT_40) \ |
| 50 | *ptr |= MPPE_L_BIT; \ |
| 51 | /* M,D,C bits not supported */ \ |
| 52 | } while (/* CONSTCOND */ 0) |
| 53 | |
| 54 | /* The reverse of the above */ |
| 55 | #define MPPE_CI_TO_OPTS(ci, opts) \ |
| 56 | do { \ |
| 57 | u_char *ptr = ci; /* u_char[4] */ \ |
| 58 | \ |
| 59 | opts = 0; \ |
| 60 | \ |
| 61 | /* H bit */ \ |
| 62 | if (!(ptr[0] & MPPE_H_BIT)) \ |
| 63 | opts |= MPPE_OPT_STATEFUL; \ |
| 64 | \ |
| 65 | /* S,L bits */ \ |
| 66 | if (ptr[3] & MPPE_S_BIT) \ |
| 67 | opts |= MPPE_OPT_128; \ |
| 68 | if (ptr[3] & MPPE_L_BIT) \ |
| 69 | opts |= MPPE_OPT_40; \ |
| 70 | \ |
| 71 | /* M,D,C bits */ \ |
| 72 | if (ptr[3] & MPPE_M_BIT) \ |
| 73 | opts |= MPPE_OPT_56; \ |
| 74 | if (ptr[3] & MPPE_D_BIT) \ |
| 75 | opts |= MPPE_OPT_D; \ |
| 76 | if (ptr[3] & MPPE_C_BIT) \ |
| 77 | opts |= MPPE_OPT_MPPC; \ |
| 78 | \ |
| 79 | /* Other bits */ \ |
| 80 | if (ptr[0] & ~MPPE_H_BIT) \ |
| 81 | opts |= MPPE_OPT_UNKNOWN; \ |
| 82 | if (ptr[1] || ptr[2]) \ |
| 83 | opts |= MPPE_OPT_UNKNOWN; \ |
| 84 | if (ptr[3] & ~MPPE_ALL_BITS) \ |
| 85 | opts |= MPPE_OPT_UNKNOWN; \ |
| 86 | } while (/* CONSTCOND */ 0) |