1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun #define MPPE_PAD 4 /* MPPE growth per frame */ 3*4882a593Smuzhiyun #define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ 4*4882a593Smuzhiyun 5*4882a593Smuzhiyun /* option bits for ccp_options.mppe */ 6*4882a593Smuzhiyun #define MPPE_OPT_40 0x01 /* 40 bit */ 7*4882a593Smuzhiyun #define MPPE_OPT_128 0x02 /* 128 bit */ 8*4882a593Smuzhiyun #define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ 9*4882a593Smuzhiyun /* unsupported opts */ 10*4882a593Smuzhiyun #define MPPE_OPT_56 0x08 /* 56 bit */ 11*4882a593Smuzhiyun #define MPPE_OPT_MPPC 0x10 /* MPPC compression */ 12*4882a593Smuzhiyun #define MPPE_OPT_D 0x20 /* Unknown */ 13*4882a593Smuzhiyun #define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) 14*4882a593Smuzhiyun #define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun /* 17*4882a593Smuzhiyun * This is not nice ... the alternative is a bitfield struct though. 18*4882a593Smuzhiyun * And unfortunately, we cannot share the same bits for the option 19*4882a593Smuzhiyun * names above since C and H are the same bit. We could do a u_int32 20*4882a593Smuzhiyun * but then we have to do a htonl() all the time and/or we still need 21*4882a593Smuzhiyun * to know which octet is which. 22*4882a593Smuzhiyun */ 23*4882a593Smuzhiyun #define MPPE_C_BIT 0x01 /* MPPC */ 24*4882a593Smuzhiyun #define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ 25*4882a593Smuzhiyun #define MPPE_L_BIT 0x20 /* 40-bit */ 26*4882a593Smuzhiyun #define MPPE_S_BIT 0x40 /* 128-bit */ 27*4882a593Smuzhiyun #define MPPE_M_BIT 0x80 /* 56-bit, not supported */ 28*4882a593Smuzhiyun #define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ 29*4882a593Smuzhiyun 30*4882a593Smuzhiyun /* Does not include H bit; used for least significant octet only. */ 31*4882a593Smuzhiyun #define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) 32*4882a593Smuzhiyun 33*4882a593Smuzhiyun /* Build a CI from mppe opts (see RFC 3078) */ 34*4882a593Smuzhiyun #define MPPE_OPTS_TO_CI(opts, ci) \ 35*4882a593Smuzhiyun do { \ 36*4882a593Smuzhiyun u_char *ptr = ci; /* u_char[4] */ \ 37*4882a593Smuzhiyun \ 38*4882a593Smuzhiyun /* H bit */ \ 39*4882a593Smuzhiyun if (opts & MPPE_OPT_STATEFUL) \ 40*4882a593Smuzhiyun *ptr++ = 0x0; \ 41*4882a593Smuzhiyun else \ 42*4882a593Smuzhiyun *ptr++ = MPPE_H_BIT; \ 43*4882a593Smuzhiyun *ptr++ = 0; \ 44*4882a593Smuzhiyun *ptr++ = 0; \ 45*4882a593Smuzhiyun \ 46*4882a593Smuzhiyun /* S,L bits */ \ 47*4882a593Smuzhiyun *ptr = 0; \ 48*4882a593Smuzhiyun if (opts & MPPE_OPT_128) \ 49*4882a593Smuzhiyun *ptr |= MPPE_S_BIT; \ 50*4882a593Smuzhiyun if (opts & MPPE_OPT_40) \ 51*4882a593Smuzhiyun *ptr |= MPPE_L_BIT; \ 52*4882a593Smuzhiyun /* M,D,C bits not supported */ \ 53*4882a593Smuzhiyun } while (/* CONSTCOND */ 0) 54*4882a593Smuzhiyun 55*4882a593Smuzhiyun /* The reverse of the above */ 56*4882a593Smuzhiyun #define MPPE_CI_TO_OPTS(ci, opts) \ 57*4882a593Smuzhiyun do { \ 58*4882a593Smuzhiyun u_char *ptr = ci; /* u_char[4] */ \ 59*4882a593Smuzhiyun \ 60*4882a593Smuzhiyun opts = 0; \ 61*4882a593Smuzhiyun \ 62*4882a593Smuzhiyun /* H bit */ \ 63*4882a593Smuzhiyun if (!(ptr[0] & MPPE_H_BIT)) \ 64*4882a593Smuzhiyun opts |= MPPE_OPT_STATEFUL; \ 65*4882a593Smuzhiyun \ 66*4882a593Smuzhiyun /* S,L bits */ \ 67*4882a593Smuzhiyun if (ptr[3] & MPPE_S_BIT) \ 68*4882a593Smuzhiyun opts |= MPPE_OPT_128; \ 69*4882a593Smuzhiyun if (ptr[3] & MPPE_L_BIT) \ 70*4882a593Smuzhiyun opts |= MPPE_OPT_40; \ 71*4882a593Smuzhiyun \ 72*4882a593Smuzhiyun /* M,D,C bits */ \ 73*4882a593Smuzhiyun if (ptr[3] & MPPE_M_BIT) \ 74*4882a593Smuzhiyun opts |= MPPE_OPT_56; \ 75*4882a593Smuzhiyun if (ptr[3] & MPPE_D_BIT) \ 76*4882a593Smuzhiyun opts |= MPPE_OPT_D; \ 77*4882a593Smuzhiyun if (ptr[3] & MPPE_C_BIT) \ 78*4882a593Smuzhiyun opts |= MPPE_OPT_MPPC; \ 79*4882a593Smuzhiyun \ 80*4882a593Smuzhiyun /* Other bits */ \ 81*4882a593Smuzhiyun if (ptr[0] & ~MPPE_H_BIT) \ 82*4882a593Smuzhiyun opts |= MPPE_OPT_UNKNOWN; \ 83*4882a593Smuzhiyun if (ptr[1] || ptr[2]) \ 84*4882a593Smuzhiyun opts |= MPPE_OPT_UNKNOWN; \ 85*4882a593Smuzhiyun if (ptr[3] & ~MPPE_ALL_BITS) \ 86*4882a593Smuzhiyun opts |= MPPE_OPT_UNKNOWN; \ 87*4882a593Smuzhiyun } while (/* CONSTCOND */ 0) 88