1 | /* $NetBSD: ppp-comp.h,v 1.16 2008/11/29 23:15:20 cube Exp $ */ |
2 | |
3 | /* |
4 | * ppp-comp.h - Definitions for doing PPP packet compression. |
5 | * |
6 | * Copyright (c) 1989-2002 Paul Mackerras. All rights reserved. |
7 | * |
8 | * Redistribution and use in source and binary forms, with or without |
9 | * modification, are permitted provided that the following conditions |
10 | * are met: |
11 | * |
12 | * 1. Redistributions of source code must retain the above copyright |
13 | * notice, this list of conditions and the following disclaimer. |
14 | * |
15 | * 2. Redistributions in binary form must reproduce the above copyright |
16 | * notice, this list of conditions and the following disclaimer in |
17 | * the documentation and/or other materials provided with the |
18 | * distribution. |
19 | * |
20 | * 3. The name(s) of the authors of this software must not be used to |
21 | * endorse or promote products derived from this software without |
22 | * prior written permission. |
23 | * |
24 | * 4. Redistributions of any form whatsoever must retain the following |
25 | * acknowledgment: |
26 | * "This product includes software developed by Paul Mackerras |
27 | * <paulus@samba.org>". |
28 | * |
29 | * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO |
30 | * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY |
31 | * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY |
32 | * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES |
33 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN |
34 | * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING |
35 | * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
36 | */ |
37 | |
38 | #ifndef _NET_PPP_COMP_H_ |
39 | #define _NET_PPP_COMP_H_ |
40 | |
41 | /* |
42 | * The following symbols control whether we include code for |
43 | * various compression methods. |
44 | */ |
45 | #ifndef DO_BSD_COMPRESS |
46 | #define DO_BSD_COMPRESS 1 /* by default, include BSD-Compress */ |
47 | #endif |
48 | #ifndef DO_DEFLATE |
49 | #define DO_DEFLATE 1 /* by default, include Deflate */ |
50 | #endif |
51 | #define DO_PREDICTOR_1 0 |
52 | #define DO_PREDICTOR_2 0 |
53 | |
54 | /* |
55 | * How many entries to make available in the compressors table |
56 | */ |
57 | #ifndef PPP_COMPRESSORS_MAX |
58 | #define PPP_COMPRESSORS_MAX 8 |
59 | #endif |
60 | |
61 | /* |
62 | * Structure giving methods for compression/decompression. |
63 | */ |
64 | #ifdef PACKETPTR |
65 | #include <sys/queue.h> |
66 | |
67 | struct compressor { |
68 | int compress_proto; /* CCP compression protocol number */ |
69 | |
70 | /* Allocate space for a compressor (transmit side) */ |
71 | void *(*comp_alloc)(u_char *, int); |
72 | /* Free space used by a compressor */ |
73 | void (*comp_free)(void *); |
74 | /* Initialize a compressor */ |
75 | int (*comp_init)(void *, u_char *, int, int, int, int); |
76 | /* Reset a compressor */ |
77 | void (*comp_reset)(void *); |
78 | /* Compress a packet */ |
79 | int (*compress)(void *, PACKETPTR *, PACKETPTR, int, int); |
80 | /* Return compression statistics */ |
81 | void (*comp_stat)(void *, struct compstat *); |
82 | |
83 | /* Allocate space for a decompressor (receive side) */ |
84 | void *(*decomp_alloc)(u_char *, int); |
85 | /* Free space used by a decompressor */ |
86 | void (*decomp_free)(void *); |
87 | /* Initialize a decompressor */ |
88 | int (*decomp_init)(void *, u_char *, int, int, int, int, int); |
89 | /* Reset a decompressor */ |
90 | void (*decomp_reset)(void *); |
91 | /* Decompress a packet. */ |
92 | int (*decompress)(void *, PACKETPTR, PACKETPTR *); |
93 | /* Update state for an incompressible packet received */ |
94 | void (*incomp)(void *, PACKETPTR); |
95 | /* Return decompression statistics */ |
96 | void (*decomp_stat)(void *, struct compstat *); |
97 | |
98 | LIST_ENTRY(compressor) comp_list; |
99 | unsigned int comp_refcnt; |
100 | }; |
101 | #endif /* PACKETPTR */ |
102 | |
103 | /* |
104 | * Return values for decompress routine. |
105 | * We need to make these distinctions so that we can disable certain |
106 | * useful functionality, namely sending a CCP reset-request as a result |
107 | * of an error detected after decompression. This is to avoid infringing |
108 | * a patent held by Motorola. |
109 | * Don't you just lurve software patents. |
110 | */ |
111 | #define DECOMP_OK 0 /* everything went OK */ |
112 | #define DECOMP_ERROR 1 /* error detected before decomp. */ |
113 | #define DECOMP_FATALERROR 2 /* error detected after decomp. */ |
114 | |
115 | /* |
116 | * CCP codes. |
117 | */ |
118 | #define CCP_CONFREQ 1 |
119 | #define CCP_CONFACK 2 |
120 | #define CCP_CONFNAK 3 |
121 | #define CCP_CONFREJ 4 |
122 | #define CCP_TERMREQ 5 |
123 | #define CCP_TERMACK 6 |
124 | #define CCP_RESETREQ 14 |
125 | #define CCP_RESETACK 15 |
126 | |
127 | /* |
128 | * Max # bytes for a CCP option |
129 | */ |
130 | #define CCP_MAX_OPTION_LENGTH 64 |
131 | |
132 | /* |
133 | * Parts of a CCP packet. |
134 | */ |
135 | #define CCP_CODE(dp) ((dp)[0]) |
136 | #define CCP_ID(dp) ((dp)[1]) |
137 | #define CCP_LENGTH(dp) (((dp)[2] << 8) + (dp)[3]) |
138 | #define CCP_HDRLEN 4 |
139 | |
140 | #define CCP_OPT_CODE(dp) ((dp)[0]) |
141 | #define CCP_OPT_LENGTH(dp) ((dp)[1]) |
142 | #define CCP_OPT_MINLEN 2 |
143 | |
144 | /* |
145 | * Definitions for BSD-Compress. |
146 | */ |
147 | #define CI_BSD_COMPRESS 21 /* config. option for BSD-Compress */ |
148 | #define CILEN_BSD_COMPRESS 3 /* length of config. option */ |
149 | |
150 | /* Macros for handling the 3rd byte of the BSD-Compress config option. */ |
151 | #define BSD_NBITS(x) ((x) & 0x1F) /* number of bits requested */ |
152 | #define BSD_VERSION(x) ((x) >> 5) /* version of option format */ |
153 | #define BSD_CURRENT_VERSION 1 /* current version number */ |
154 | #define BSD_MAKE_OPT(v, n) (((v) << 5) | (n)) |
155 | |
156 | #define BSD_MIN_BITS 9 /* smallest code size supported */ |
157 | #define BSD_MAX_BITS 15 /* largest code size supported */ |
158 | |
159 | /* |
160 | * Definitions for Deflate. |
161 | */ |
162 | #define CI_DEFLATE 26 /* config option for Deflate */ |
163 | #define CI_DEFLATE_DRAFT 24 /* value used in original draft RFC */ |
164 | |
165 | #define CILEN_DEFLATE 4 /* length of its config option */ |
166 | |
167 | #define DEFLATE_MIN_SIZE 8 |
168 | #define DEFLATE_MAX_SIZE 15 |
169 | #define DEFLATE_METHOD_VAL 8 |
170 | #define DEFLATE_SIZE(x) (((x) >> 4) + DEFLATE_MIN_SIZE) |
171 | #define DEFLATE_METHOD(x) ((x) & 0x0F) |
172 | #define DEFLATE_MAKE_OPT(w) ((((w) - DEFLATE_MIN_SIZE) << 4) \ |
173 | + DEFLATE_METHOD_VAL) |
174 | #define DEFLATE_CHK_SEQUENCE 0 |
175 | |
176 | /* |
177 | * Definitions for MPPE. |
178 | */ |
179 | #define CI_MPPE 18 /* config option for MPPE */ |
180 | #define CILEN_MPPE 6 /* length of config option */ |
181 | |
182 | #define MPPE_PAD 4 /* MPPE growth per frame */ |
183 | #define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ |
184 | |
185 | /* option bits for ccp_options.mppe */ |
186 | #define MPPE_OPT_40 0x01 /* 40 bit */ |
187 | #define MPPE_OPT_128 0x02 /* 128 bit */ |
188 | #define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ |
189 | /* unsupported opts */ |
190 | #define MPPE_OPT_56 0x08 /* 56 bit */ |
191 | #define MPPE_OPT_MPPC 0x10 /* MPPC compression */ |
192 | #define MPPE_OPT_D 0x20 /* Unknown */ |
193 | #define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) |
194 | #define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ |
195 | |
196 | /* |
197 | * This is not nice ... the alternative is a bitfield struct though. |
198 | * And unfortunately, we cannot share the same bits for the option |
199 | * names above since C and H are the same bit. We could do a uint32_t |
200 | * but then we have to do a htonl() all the time and/or we still need |
201 | * to know which octet is which. |
202 | */ |
203 | #define MPPE_C_BIT 0x01 /* MPPC */ |
204 | #define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ |
205 | #define MPPE_L_BIT 0x20 /* 40-bit */ |
206 | #define MPPE_S_BIT 0x40 /* 128-bit */ |
207 | #define MPPE_M_BIT 0x80 /* 56-bit, not supported */ |
208 | #define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ |
209 | |
210 | /* Does not include H bit; used for least significant octet only. */ |
211 | #define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) |
212 | |
213 | /* Build a CI from mppe opts (see RFC 3078) */ |
214 | #define MPPE_OPTS_TO_CI(opts, ci) \ |
215 | do { \ |
216 | u_char *ptr = ci; /* u_char[4] */ \ |
217 | \ |
218 | /* H bit */ \ |
219 | if (opts & MPPE_OPT_STATEFUL) \ |
220 | *ptr++ = 0x0; \ |
221 | else \ |
222 | *ptr++ = MPPE_H_BIT; \ |
223 | *ptr++ = 0; \ |
224 | *ptr++ = 0; \ |
225 | \ |
226 | /* S,L bits */ \ |
227 | *ptr = 0; \ |
228 | if (opts & MPPE_OPT_128) \ |
229 | *ptr |= MPPE_S_BIT; \ |
230 | if (opts & MPPE_OPT_40) \ |
231 | *ptr |= MPPE_L_BIT; \ |
232 | /* M,D,C bits not supported */ \ |
233 | } while (/* CONSTCOND */ 0) |
234 | |
235 | /* The reverse of the above */ |
236 | #define MPPE_CI_TO_OPTS(ci, opts) \ |
237 | do { \ |
238 | u_char *ptr = ci; /* u_char[4] */ \ |
239 | \ |
240 | opts = 0; \ |
241 | \ |
242 | /* H bit */ \ |
243 | if (!(ptr[0] & MPPE_H_BIT)) \ |
244 | opts |= MPPE_OPT_STATEFUL; \ |
245 | \ |
246 | /* S,L bits */ \ |
247 | if (ptr[3] & MPPE_S_BIT) \ |
248 | opts |= MPPE_OPT_128; \ |
249 | if (ptr[3] & MPPE_L_BIT) \ |
250 | opts |= MPPE_OPT_40; \ |
251 | \ |
252 | /* M,D,C bits */ \ |
253 | if (ptr[3] & MPPE_M_BIT) \ |
254 | opts |= MPPE_OPT_56; \ |
255 | if (ptr[3] & MPPE_D_BIT) \ |
256 | opts |= MPPE_OPT_D; \ |
257 | if (ptr[3] & MPPE_C_BIT) \ |
258 | opts |= MPPE_OPT_MPPC; \ |
259 | \ |
260 | /* Other bits */ \ |
261 | if (ptr[0] & ~MPPE_H_BIT) \ |
262 | opts |= MPPE_OPT_UNKNOWN; \ |
263 | if (ptr[1] || ptr[2]) \ |
264 | opts |= MPPE_OPT_UNKNOWN; \ |
265 | if (ptr[3] & ~MPPE_ALL_BITS) \ |
266 | opts |= MPPE_OPT_UNKNOWN; \ |
267 | } while (/* CONSTCOND */ 0) |
268 | |
269 | /* |
270 | * Definitions for other, as yet unsupported, compression methods. |
271 | */ |
272 | #define CI_PREDICTOR_1 1 /* config option for Predictor-1 */ |
273 | #define CILEN_PREDICTOR_1 2 /* length of its config option */ |
274 | #define CI_PREDICTOR_2 2 /* config option for Predictor-2 */ |
275 | #define CILEN_PREDICTOR_2 2 /* length of its config option */ |
276 | |
277 | #endif /* !_NET_PPP_COMP_H_ */ |
278 | |