| #define MPPE_PAD 4 /* MPPE growth per frame */ |
| #define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ |
| |
| /* option bits for ccp_options.mppe */ |
| #define MPPE_OPT_40 0x01 /* 40 bit */ |
| #define MPPE_OPT_128 0x02 /* 128 bit */ |
| #define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ |
| /* unsupported opts */ |
| #define MPPE_OPT_56 0x08 /* 56 bit */ |
| #define MPPE_OPT_MPPC 0x10 /* MPPC compression */ |
| #define MPPE_OPT_D 0x20 /* Unknown */ |
| #define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) |
| #define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ |
| |
| /* |
| * This is not nice ... the alternative is a bitfield struct though. |
| * And unfortunately, we cannot share the same bits for the option |
| * names above since C and H are the same bit. We could do a u_int32 |
| * but then we have to do a htonl() all the time and/or we still need |
| * to know which octet is which. |
| */ |
| #define MPPE_C_BIT 0x01 /* MPPC */ |
| #define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ |
| #define MPPE_L_BIT 0x20 /* 40-bit */ |
| #define MPPE_S_BIT 0x40 /* 128-bit */ |
| #define MPPE_M_BIT 0x80 /* 56-bit, not supported */ |
| #define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ |
| |
| /* Does not include H bit; used for least significant octet only. */ |
| #define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) |
| |
| /* Build a CI from mppe opts (see RFC 3078) */ |
| #define MPPE_OPTS_TO_CI(opts, ci) \ |
| do { \ |
| u_char *ptr = ci; /* u_char[4] */ \ |
| \ |
| /* H bit */ \ |
| if (opts & MPPE_OPT_STATEFUL) \ |
| *ptr++ = 0x0; \ |
| else \ |
| *ptr++ = MPPE_H_BIT; \ |
| *ptr++ = 0; \ |
| *ptr++ = 0; \ |
| \ |
| /* S,L bits */ \ |
| *ptr = 0; \ |
| if (opts & MPPE_OPT_128) \ |
| *ptr |= MPPE_S_BIT; \ |
| if (opts & MPPE_OPT_40) \ |
| *ptr |= MPPE_L_BIT; \ |
| /* M,D,C bits not supported */ \ |
| } while (/* CONSTCOND */ 0) |
| |
| /* The reverse of the above */ |
| #define MPPE_CI_TO_OPTS(ci, opts) \ |
| do { \ |
| u_char *ptr = ci; /* u_char[4] */ \ |
| \ |
| opts = 0; \ |
| \ |
| /* H bit */ \ |
| if (!(ptr[0] & MPPE_H_BIT)) \ |
| opts |= MPPE_OPT_STATEFUL; \ |
| \ |
| /* S,L bits */ \ |
| if (ptr[3] & MPPE_S_BIT) \ |
| opts |= MPPE_OPT_128; \ |
| if (ptr[3] & MPPE_L_BIT) \ |
| opts |= MPPE_OPT_40; \ |
| \ |
| /* M,D,C bits */ \ |
| if (ptr[3] & MPPE_M_BIT) \ |
| opts |= MPPE_OPT_56; \ |
| if (ptr[3] & MPPE_D_BIT) \ |
| opts |= MPPE_OPT_D; \ |
| if (ptr[3] & MPPE_C_BIT) \ |
| opts |= MPPE_OPT_MPPC; \ |
| \ |
| /* Other bits */ \ |
| if (ptr[0] & ~MPPE_H_BIT) \ |
| opts |= MPPE_OPT_UNKNOWN; \ |
| if (ptr[1] || ptr[2]) \ |
| opts |= MPPE_OPT_UNKNOWN; \ |
| if (ptr[3] & ~MPPE_ALL_BITS) \ |
| opts |= MPPE_OPT_UNKNOWN; \ |
| } while (/* CONSTCOND */ 0) |
