e576be50 |
1 | /* |
2 | * internal.h |
3 | * - declarations of private objects with external linkage (adns__*) |
4 | * - definitons of internal macros |
5 | * - comments regarding library data structures |
6 | */ |
7 | /* |
8 | * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson |
9 | * |
10 | * This program is free software; you can redistribute it and/or modify |
11 | * it under the terms of the GNU General Public License as published by |
12 | * the Free Software Foundation; either version 2, or (at your option) |
13 | * any later version. |
14 | * |
15 | * This program is distributed in the hope that it will be useful, |
16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
18 | * GNU General Public License for more details. |
19 | * |
20 | * You should have received a copy of the GNU General Public License |
21 | * along with this program; if not, write to the Free Software Foundation, |
22 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
23 | */ |
37e28fde |
24 | |
25 | #ifndef ADNS_INTERNAL_H_INCLUDED |
26 | #define ADNS_INTERNAL_H_INCLUDED |
27 | |
4353a5c4 |
28 | #define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b))) |
29 | typedef unsigned char byte; |
30 | |
31 | #include <stdarg.h> |
32 | #include <assert.h> |
33 | #include <unistd.h> |
34 | |
37e28fde |
35 | #include <sys/time.h> |
36 | |
37 | #include "adns.h" |
38 | |
39 | /* Configuration and constants */ |
40 | |
41 | #define MAXSERVERS 5 |
b9de380c |
42 | #define UDPMAXRETRIES /*15*/5 |
37e28fde |
43 | #define UDPRETRYMS 2000 |
44 | #define TCPMS 30000 |
45 | #define LOCALRESOURCEMS 20 |
b9de380c |
46 | |
98a3f706 |
47 | #define DNS_PORT 53 |
b9de380c |
48 | #define DNS_MAXUDP 512 |
49 | #define DNS_MAXDOMAIN 255 |
50 | #define DNS_HDRSIZE 12 |
51 | #define DNS_CLASS_IN 1 |
37e28fde |
52 | |
98a3f706 |
53 | typedef enum { |
54 | rcode_noerror, |
55 | rcode_formaterror, |
56 | rcode_servfail, |
57 | rcode_nxdomain, |
58 | rcode_notimp, |
59 | rcode_refused |
60 | } dns_rcode; |
61 | |
37e28fde |
62 | /* Shared data structures */ |
63 | |
4353a5c4 |
64 | typedef union { |
37e28fde |
65 | adns_status status; |
66 | char *cp; |
67 | adns_rrtype type; |
4353a5c4 |
68 | int i; |
37e28fde |
69 | struct in_addr ia; |
70 | unsigned long ul; |
4353a5c4 |
71 | } rr_align; |
72 | |
73 | typedef struct { |
74 | int used, avail; |
75 | byte *buf; |
76 | } vbuf; |
77 | |
78 | typedef union { |
79 | void *ext; |
80 | int dmaddr_index; |
81 | } qcontext; |
37e28fde |
82 | |
0ba0614a |
83 | typedef struct { |
0ba0614a |
84 | adns_rrtype type; |
68442019 |
85 | const char *name; |
98a3f706 |
86 | int rrsz; |
8e5b0abb |
87 | |
3955725c |
88 | adns_status (*parse)(adns_query qu, int serv, |
31144a72 |
89 | const byte *dgram, int dglen, int cbyte, int max, |
90 | void *store_r); |
91 | /* Parse one RR, in dgram of length dglen, starting at cbyte and |
92 | * extending until at most max. |
93 | * |
94 | * The RR should be stored at *store_r, of length qu->typei->rrsz. |
95 | * |
96 | * If there is an overrun which might indicate truncation, it should set |
97 | * *rdstart to -1; otherwise it may set it to anything else positive. |
8e5b0abb |
98 | */ |
99 | |
3955725c |
100 | void (*makefinal)(adns_query qu, void *data); |
8e5b0abb |
101 | /* Change memory management of *data. |
102 | * Previously, used alloc_interim, now use alloc_final. |
31144a72 |
103 | */ |
0ba0614a |
104 | } typeinfo; |
105 | |
8e5b0abb |
106 | typedef struct allocnode { |
107 | struct allocnode *next; |
108 | } allocnode; |
109 | |
110 | union maxalign { |
111 | byte d[1]; |
112 | struct in_addr ia; |
113 | long l; |
114 | void *p; |
115 | void (*fp)(void); |
116 | union maxalign *up; |
117 | } data; |
118 | |
37e28fde |
119 | struct adns__query { |
3955725c |
120 | adns_state ads; |
ddfda861 |
121 | enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state; |
4353a5c4 |
122 | adns_query back, next, parent; |
37e28fde |
123 | struct { adns_query head, tail; } children; |
124 | struct { adns_query back, next; } siblings; |
8e5b0abb |
125 | struct allocnode *allocations; |
68442019 |
126 | int interim_allocd; |
127 | void *final_allocspace; |
0ba0614a |
128 | |
129 | const typeinfo *typei; |
8e5b0abb |
130 | char *query_dgram; |
131 | int query_dglen; |
31144a72 |
132 | |
8e5b0abb |
133 | vbuf vb; |
134 | /* General-purpose messing-about buffer. |
135 | * Wherever a `big' interface is crossed, this may be corrupted/changed |
136 | * unless otherwise specified. |
137 | */ |
138 | |
139 | adns_answer *answer; |
140 | /* This is allocated when a query is submitted, to avoid being unable |
141 | * to relate errors to queries if we run out of memory. During |
142 | * query processing status, rrs is 0. cname is set if |
143 | * we found a cname (this corresponds to cname_dgram in the query |
144 | * structure). type is set from the word go. nrrs and rrs |
145 | * are set together, when we find how many rrs there are. |
146 | */ |
31144a72 |
147 | |
31144a72 |
148 | byte *cname_dgram; |
149 | int cname_dglen, cname_begin; |
3955725c |
150 | /* If non-0, has been allocated using . */ |
31144a72 |
151 | |
ddfda861 |
152 | int id, flags, udpretries; |
4353a5c4 |
153 | int udpnextserver; |
154 | unsigned long udpsent, tcpfailed; /* bitmap indexed by server */ |
37e28fde |
155 | struct timeval timeout; |
4353a5c4 |
156 | qcontext context; |
ddfda861 |
157 | |
37e28fde |
158 | /* Possible states: |
ddfda861 |
159 | * |
8e5b0abb |
160 | * state Queue child id nextudpserver sentudp failedtcp |
161 | * |
162 | * udp NONE null >=0 0 zero zero |
163 | * udp timew null >=0 any nonzero zero |
164 | * udp NONE null >=0 any nonzero zero |
165 | * |
166 | * tcpwait timew null >=0 irrelevant zero any |
167 | * tcpsent timew null >=0 irrelevant zero any |
168 | * |
169 | * child childw set >=0 irrelevant irrelevant irrelevant |
170 | * done output null -1 irrelevant irrelevant irrelevant |
ddfda861 |
171 | * |
172 | * +------------------------+ |
173 | * START -----> | udp/NONE | |
174 | * +------------------------+ |
175 | * / |\ \ |
176 | * too big for UDP / UDP timeout \ \ send via UDP |
177 | * do this ASAP! / more retries \ \ do this ASAP! |
178 | * |_ desired \ _| |
179 | * +---------------+ +-----------+ |
180 | * | tcpwait/timew | ____ | udp/timew | |
181 | * +---------------+ \ +-----------+ |
182 | * | ^ | | | |
183 | * TCP conn'd; | | TCP died | | | |
184 | * send via TCP | | more | UDP timeout | | |
185 | * do this ASAP! | | servers | no more | | |
186 | * v | to try | retries | | |
187 | * +---------------+ | desired | | |
188 | * | tcpsent/timew | ____ | | | |
189 | * +---------------+ \| | | |
190 | * \ \ TCP died | TCP | | |
191 | * \ \ no more | timeout / | |
192 | * \ \ servers | / | |
193 | * \ \ to try | / | |
194 | * got \ \ v |_ / got |
195 | * reply \ _| +------------------+ / reply |
196 | * \ | done/output FAIL | / |
197 | * \ +------------------+ / |
198 | * \ / |
199 | * _| |_ |
200 | * (..... got reply ....) |
201 | * / \ |
202 | * need child query/ies / \ no child query |
203 | * / \ |
204 | * |_ _| |
205 | * +--------------+ +----------------+ |
206 | * | child/childw | ----------------> | done/output OK | |
207 | * +--------------+ children done +----------------+ |
37e28fde |
208 | */ |
209 | }; |
210 | |
37e28fde |
211 | struct adns__state { |
37e28fde |
212 | adns_initflags iflags; |
213 | FILE *diagfile; |
ddfda861 |
214 | struct { adns_query head, tail; } timew, childw, output; |
4353a5c4 |
215 | int nextid, udpsocket, tcpsocket; |
8e5b0abb |
216 | vbuf tcpsend, tcprecv; |
37e28fde |
217 | int nservers, tcpserver; |
8402e34c |
218 | enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate; |
37e28fde |
219 | struct timeval tcptimeout; |
220 | struct server { |
221 | struct in_addr addr; |
222 | } servers[MAXSERVERS]; |
223 | }; |
224 | |
225 | /* From setup.c: */ |
226 | |
e576be50 |
227 | int adns__setnonblock(adns_state ads, int fd); /* => errno value */ |
228 | |
229 | /* From general.c: */ |
230 | |
4353a5c4 |
231 | void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent, |
68442019 |
232 | int serv, adns_query qu, const char *fmt, va_list al); |
31144a72 |
233 | |
234 | void adns__debug(adns_state ads, int serv, adns_query qu, |
68442019 |
235 | const char *fmt, ...) PRINTFFORMAT(4,5); |
31144a72 |
236 | void adns__warn(adns_state ads, int serv, adns_query qu, |
68442019 |
237 | const char *fmt, ...) PRINTFFORMAT(4,5); |
31144a72 |
238 | void adns__diag(adns_state ads, int serv, adns_query qu, |
68442019 |
239 | const char *fmt, ...) PRINTFFORMAT(4,5); |
37e28fde |
240 | |
4353a5c4 |
241 | int adns__vbuf_ensure(vbuf *vb, int want); |
9557e604 |
242 | int adns__vbuf_appendstr(vbuf *vb, const char *data); /* does not include nul */ |
4353a5c4 |
243 | int adns__vbuf_append(vbuf *vb, const byte *data, int len); |
ddfda861 |
244 | /* 1=>success, 0=>realloc failed */ |
4353a5c4 |
245 | void adns__vbuf_appendq(vbuf *vb, const byte *data, int len); |
246 | void adns__vbuf_init(vbuf *vb); |
8e5b0abb |
247 | void adns__vbuf_free(vbuf *vb); |
4353a5c4 |
248 | |
e576be50 |
249 | const char *adns__diag_domain(adns_state ads, int serv, adns_query qu, vbuf *vb, |
250 | int flags, const byte *dgram, int dglen, int cbyte); |
251 | /* Unpicks a domain in a datagram and returns a string suitable for |
252 | * printing it as. Never fails - if an error occurs, it will |
253 | * return some kind of string describing the error. |
254 | * |
3955725c |
255 | * serv may be -1 and qu may be 0. vb must have been initialised, |
e576be50 |
256 | * and will be left in an arbitrary consistent state. |
257 | * |
258 | * Returns either vb->buf, or a pointer to a string literal. Do not modify |
259 | * vb before using the return value. |
260 | */ |
261 | |
262 | /* From transmit.c: */ |
ddfda861 |
263 | |
3955725c |
264 | adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r, |
265 | const char *owner, int ol, |
e576be50 |
266 | const typeinfo *typei, adns_queryflags flags); |
267 | /* Assembles a query packet in vb, and returns id at *id_r. */ |
268 | |
3955725c |
269 | void adns__query_tcp(adns_query qu, struct timeval now); |
e576be50 |
270 | /* Query must be in state tcpwait/timew; it will be moved to a new state |
271 | * if possible and no further processing can be done on it for now. |
272 | * (Resulting state is one of tcpwait/timew (if server not connected), |
273 | * tcpsent/timew, child/childw or done/output.) |
274 | * |
275 | * adns__tcp_tryconnect should already have been called - _tcp |
276 | * will only use an existing connection (if there is one), which it |
277 | * may break. If the conn list lost then the caller is responsible for any |
278 | * reestablishment and retry. |
279 | */ |
280 | |
3955725c |
281 | void adns__query_udp(adns_query qu, struct timeval now); |
e576be50 |
282 | /* Query must be in state udp/NONE; it will be moved to a new state, |
283 | * and no further processing can be done on it for now. |
284 | * (Resulting state is one of udp/timew, tcpwait/timew (if server not connected), |
285 | * tcpsent/timew, child/childw or done/output.) |
286 | */ |
287 | |
288 | /* From query.c: */ |
37e28fde |
289 | |
8e5b0abb |
290 | int adns__internal_submit(adns_state ads, adns_query *query_r, |
3955725c |
291 | const typeinfo *typei, vbuf *qumsg_vb, int id, |
8e5b0abb |
292 | adns_queryflags flags, struct timeval now, |
293 | adns_status failstat, const qcontext *ctx); |
294 | /* Submits a query (for internal use, called during external submits). |
295 | * |
296 | * The new query is returned in *query_r, or we return adns_s_nomemory. |
297 | * |
68442019 |
298 | * The query datagram should already have been assembled in qumsg_vb; |
299 | * the memory for it is _taken over_ by this routine whether it |
300 | * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb). |
8e5b0abb |
301 | * |
302 | * If failstat is nonzero then if we are successful in creating the query |
303 | * it is immediately failed with code failstat (but _submit still succeds). |
304 | * |
305 | * ctx is copied byte-for-byte into the query. |
306 | */ |
307 | |
308 | void *adns__alloc_interim(adns_query qu, size_t sz); |
309 | /* Allocates some memory, and records which query it came from |
310 | * and how much there was. |
311 | * |
312 | * If an error occurs in the query, all its memory is simply freed. |
313 | * |
314 | * If the query succeeds, one large buffer will be made which is |
315 | * big enough for all these allocations, and then adns__alloc_final |
316 | * will get memory from this buffer. |
317 | * |
318 | * _alloc_interim can fail, in which case it will fail the query too, |
319 | * so nothing more need be done with it. |
a49a6d7b |
320 | * |
321 | * adns__alloc_interim(qu,0) will not return 0, but it will not |
322 | * necessarily return a distinct pointer each time. |
8e5b0abb |
323 | */ |
324 | |
3955725c |
325 | void *adns__alloc_mine(adns_query qu, size_t sz); |
326 | /* Like _interim, but does not record the length for later |
327 | * copying into the answer. This just ensures that the memory |
328 | * will be freed when we're done with the query. |
329 | */ |
330 | |
8e5b0abb |
331 | void *adns__alloc_final(adns_query qu, size_t sz); |
a49a6d7b |
332 | /* Cannot fail, and cannot return 0. |
8e5b0abb |
333 | */ |
37e28fde |
334 | |
68442019 |
335 | void adns__makefinal_block(adns_query qu, void **blpp, size_t sz); |
336 | void adns__makefinal_str(adns_query qu, char **strp); |
337 | |
3955725c |
338 | void adns__reset_cnameonly(adns_query qu); |
68442019 |
339 | /* Resets all of the memory management stuff etc. to |
340 | * take account of only the CNAME. Used when we find an error somewhere |
341 | * and want to just report the error (with perhaps CNAME info), and also |
342 | * when we're halfway through RRs in a datagram and discover that we |
343 | * need to retry the query. |
344 | */ |
e576be50 |
345 | |
3955725c |
346 | void adns__query_done(adns_query qu); |
347 | void adns__query_fail(adns_query qu, adns_status stat); |
68442019 |
348 | |
4353a5c4 |
349 | /* From reply.c: */ |
350 | |
98a3f706 |
351 | void adns__procdgram(adns_state ads, const byte *dgram, int len, |
352 | int serv, struct timeval now); |
353 | |
354 | /* From types.c: */ |
355 | |
356 | const typeinfo *adns__findtype(adns_rrtype type); |
357 | |
358 | /* From parse.c: */ |
359 | |
f1e474dd |
360 | typedef struct { |
68442019 |
361 | adns_state ads; |
3955725c |
362 | adns_query qu; |
68442019 |
363 | int serv; |
f1e474dd |
364 | const byte *dgram; |
365 | int dglen, max, cbyte, namelen; |
3955725c |
366 | int *dmend_r; |
f1e474dd |
367 | } findlabel_state; |
368 | |
3955725c |
369 | void adns__findlabel_start(findlabel_state *fls, adns_state ads, |
370 | int serv, adns_query qu, |
f1e474dd |
371 | const byte *dgram, int dglen, int max, |
372 | int dmbegin, int *dmend_rlater); |
373 | /* Finds labels in a domain in a datagram. |
374 | * |
375 | * Call this routine first. |
3955725c |
376 | * dmend_rlater may be null. ads (and of course fls) may not be. |
377 | * serv may be -1, qu may be null - they are for error reporting. |
f1e474dd |
378 | */ |
379 | |
3955725c |
380 | adns_status adns__findlabel_next(findlabel_state *fls, int *lablen_r, int *labstart_r); |
f1e474dd |
381 | /* Then, call this one repeatedly. |
382 | * |
383 | * It will return adns_s_ok if all is well, and tell you the length |
384 | * and start of successive labels. labstart_r may be null, but |
385 | * lablen_r must not be. |
386 | * |
387 | * After the last label, it will return with *lablen_r zero. |
388 | * Do not then call it again; instead, just throw away the findlabel_state. |
389 | * |
390 | * *dmend_rlater will have been set to point to the next part of |
391 | * the datagram after the label (or after the uncompressed part, |
392 | * if compression was used). *namelen_rlater will have been set |
393 | * to the length of the domain name (total length of labels plus |
394 | * 1 for each intervening dot). |
395 | * |
396 | * If the datagram appears to be truncated, *lablen_r will be -1. |
397 | * *dmend_rlater, *labstart_r and *namelen_r may contain garbage. |
398 | * Do not call _next again. |
399 | * |
400 | * There may also be errors, in which case *dmend_rlater, |
401 | * *namelen_rlater, *lablen_r and *labstart_r may contain garbage. |
402 | * Do not then call findlabel_next again. |
403 | */ |
404 | |
3955725c |
405 | adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu, |
406 | vbuf *vb, int flags, |
407 | const byte *dgram, int dglen, int *cbyte_io, int max); |
f1e474dd |
408 | /* vb must already have been initialised; it will be reset if necessary. |
409 | * If there is truncation, vb->used will be set to 0; otherwise |
410 | * (if there is no error) vb will be null-terminated. |
411 | * If there is an error vb and *cbyte_io may be left indeterminate. |
3955725c |
412 | * |
413 | * serv may be -1 and qu may be 0 - they are used for error reporting only. |
f1e474dd |
414 | */ |
415 | |
3955725c |
416 | adns_status adns__findrr(adns_query qu, int serv, |
f1e474dd |
417 | const byte *dgram, int dglen, int *cbyte_io, |
418 | int *type_r, int *class_r, int *rdlen_r, int *rdstart_r, |
3955725c |
419 | int *ownermatchedquery_r); |
f1e474dd |
420 | /* Finds the extent and some of the contents of an RR in a datagram |
421 | * and does some checks. The datagram is *dgram, length dglen, and |
422 | * the RR starts at *cbyte_io (which is updated afterwards to point |
423 | * to the end of the RR). |
424 | * |
425 | * The type, class and RRdata length and start are returned iff |
426 | * the corresponding pointer variables are not null. type_r and |
427 | * class_r may not be null. |
428 | * |
3955725c |
429 | * If ownermatchedquery_r != 0 then the owner domain of this |
430 | * RR will be compared with that in the query (or, if the query |
431 | * has gone to a CNAME lookup, with the canonical name). |
432 | * In this case, *ownermatchedquery_r will be set to 0 or 1. |
433 | * The query datagram (or CNAME datagram) MUST be valid and not truncated. |
f1e474dd |
434 | * |
435 | * If there is truncation then *type_r will be set to -1 and |
436 | * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be |
437 | * undefined. |
438 | * |
3955725c |
439 | * qu must obviously be non-null. |
440 | * |
f1e474dd |
441 | * If an error is returned then *type_r will be undefined too. |
442 | */ |
98a3f706 |
443 | |
f1e474dd |
444 | int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len); |
8402e34c |
445 | |
446 | /* From event.c: */ |
4353a5c4 |
447 | |
8402e34c |
448 | void adns__tcp_broken(adns_state ads, const char *what, const char *why); |
4353a5c4 |
449 | void adns__tcp_tryconnect(adns_state ads, struct timeval now); |
e576be50 |
450 | |
4353a5c4 |
451 | void adns__autosys(adns_state ads, struct timeval now); |
e576be50 |
452 | /* Make all the system calls we want to if the application wants us to. */ |
37e28fde |
453 | |
454 | /* Useful static inline functions: */ |
455 | |
456 | static inline void timevaladd(struct timeval *tv_io, long ms) { |
457 | struct timeval tmp; |
458 | assert(ms>=0); |
459 | tmp= *tv_io; |
94436798 |
460 | tmp.tv_usec += (ms%1000)*1000000; |
37e28fde |
461 | tmp.tv_sec += ms/1000; |
94436798 |
462 | if (tmp.tv_usec >= 1000000) { tmp.tv_sec++; tmp.tv_usec -= 1000; } |
37e28fde |
463 | *tv_io= tmp; |
ddfda861 |
464 | } |
37e28fde |
465 | |
466 | static inline int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; } |
467 | static inline int ctype_digit(int c) { return c>='0' && c<='9'; } |
98a3f706 |
468 | static inline int ctype_alpha(int c) { |
469 | return (c >= 'a' && c <= 'z') || (c >= 'A' || c <= 'Z'); |
470 | } |
37e28fde |
471 | |
472 | /* Useful macros */ |
473 | |
8e5b0abb |
474 | #define MEM_ROUND(sz) \ |
475 | (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \ |
476 | * sizeof(union maxalign) ) |
477 | |
4353a5c4 |
478 | #define LIST_INIT(list) ((list).head= (list).tail= 0) |
479 | |
37e28fde |
480 | #define LIST_UNLINK_PART(list,node,part) \ |
481 | do { \ |
482 | if ((node)->back) (node)->back->part next= (node)->part next; \ |
483 | else (list).head= (node)->part next; \ |
484 | if ((node)->next) (node)->next->part back= (node)->part back; \ |
485 | else (list).tail= (node)->part back; \ |
486 | } while(0) |
487 | |
488 | #define LIST_LINK_TAIL_PART(list,node,part) \ |
489 | do { \ |
490 | (node)->part back= 0; \ |
491 | (node)->part next= (list).tail; \ |
492 | if ((list).tail) (list).tail->part back= (node); else (list).part head= (node); \ |
493 | (list).tail= (node); \ |
494 | } while(0) |
495 | |
496 | #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,) |
4353a5c4 |
497 | #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,) |
37e28fde |
498 | |
98a3f706 |
499 | #define GETIL_B(cb) (dgram[(cb)++]) |
500 | #define GET_B(cb,tv) ((tv)= GETIL_B((cb))) |
501 | #define GET_W(cb,tv) ((tv)=0, (tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv)) |
502 | |
37e28fde |
503 | #endif |