3 * - declarations of private objects with external linkage (adns__*)
4 * - definitons of internal macros
5 * - comments regarding library data structures
8 * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
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)
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.
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.
25 #ifndef ADNS_INTERNAL_H_INCLUDED
26 #define ADNS_INTERNAL_H_INCLUDED
28 #define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b)))
29 typedef unsigned char byte;
39 /* Configuration and constants */
42 #define UDPMAXRETRIES /*15*/5
43 #define UDPRETRYMS 2000
45 #define LOCALRESOURCEMS 20
48 #define DNS_MAXUDP 512
49 #define DNS_MAXDOMAIN 255
50 #define DNS_HDRSIZE 12
51 #define DNS_CLASS_IN 1
62 /* Shared data structures */
86 int serv, dglen, max, nsstart;
95 void (*makefinal)(adns_query qu, void *data);
96 /* Change memory management of *data.
97 * Previously, used alloc_interim, now use alloc_final.
100 adns_status (*convstring)(vbuf *vb, const void *data);
101 /* Converts the RR data to a string representation in vbuf.
102 * vbuf will be appended to (it must have been initialised),
103 * and will not be null-terminated by convstring.
106 adns_status (*parse)(const struct parseinfo *pai, int cbyte, void *store_r);
107 /* Parse one RR, in dgram of length dglen, starting at cbyte and
108 * extending until at most max.
110 * The RR should be stored at *store_r, of length qu->typei->rrsz.
112 * If there is an overrun which might indicate truncation, it should set
113 * *rdstart to -1; otherwise it may set it to anything else positive.
115 * nsstart is the offset of the authority section.
118 int (*diff_needswap)(const void *datap_a, const void *datap_b);
119 /* Returns !0 if RR a should be strictly after RR b in the sort order,
120 * 0 otherwise. Must not fail.
124 typedef struct allocnode {
125 struct allocnode *next;
139 enum { query_udp, query_tcpwait, query_tcpsent, query_child, query_done } state;
140 adns_query back, next, parent;
141 struct { adns_query head, tail; } children;
142 struct { adns_query back, next; } siblings;
143 struct allocnode *allocations;
145 void *final_allocspace;
147 const typeinfo *typei;
152 /* General-purpose messing-about buffer.
153 * Wherever a `big' interface is crossed, this may be corrupted/changed
154 * unless otherwise specified.
158 /* This is allocated when a query is submitted, to avoid being unable
159 * to relate errors to queries if we run out of memory. During
160 * query processing status, rrs is 0. cname is set if
161 * we found a cname (this corresponds to cname_dgram in the query
162 * structure). type is set from the word go. nrrs and rrs
163 * are set together, when we find how many rrs there are.
167 int cname_dglen, cname_begin;
168 /* If non-0, has been allocated using . */
170 int id, flags, udpretries;
172 unsigned long udpsent, tcpfailed; /* bitmap indexed by server */
173 struct timeval timeout;
178 * state Queue child id nextudpserver sentudp failedtcp
180 * udp NONE null >=0 0 zero zero
181 * udp timew null >=0 any nonzero zero
182 * udp NONE null >=0 any nonzero zero
184 * tcpwait timew null >=0 irrelevant zero any
185 * tcpsent timew null >=0 irrelevant zero any
187 * child childw set >=0 irrelevant irrelevant irrelevant
188 * done output null -1 irrelevant irrelevant irrelevant
190 * +------------------------+
191 * START -----> | udp/NONE |
192 * +------------------------+
194 * too big for UDP / UDP timeout \ \ send via UDP
195 * do this ASAP! / more retries \ \ do this ASAP!
197 * +---------------+ +-----------+
198 * | tcpwait/timew | ____ | udp/timew |
199 * +---------------+ \ +-----------+
201 * TCP conn'd; | | TCP died | | |
202 * send via TCP | | more | UDP timeout | |
203 * do this ASAP! | | servers | no more | |
204 * v | to try | retries | |
205 * +---------------+ | desired | |
206 * | tcpsent/timew | ____ | | |
207 * +---------------+ \| | |
208 * \ \ TCP died | TCP | |
209 * \ \ no more | timeout / |
213 * reply \ _| +------------------+ / reply
214 * \ | done/output FAIL | /
215 * \ +------------------+ /
218 * (..... got reply ....)
220 * need child query/ies / \ no child query
223 * +--------------+ +----------------+
224 * | child/childw | ----------------> | done/output OK |
225 * +--------------+ children done +----------------+
230 adns_initflags iflags;
232 struct { adns_query head, tail; } timew, childw, output;
233 int nextid, udpsocket, tcpsocket;
234 vbuf tcpsend, tcprecv;
235 int nservers, tcpserver;
236 enum adns__tcpstate { server_disconnected, server_connecting, server_ok } tcpstate;
237 struct timeval tcptimeout;
240 } servers[MAXSERVERS];
245 int adns__setnonblock(adns_state ads, int fd); /* => errno value */
247 /* From general.c: */
249 void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
250 int serv, adns_query qu, const char *fmt, va_list al);
252 void adns__debug(adns_state ads, int serv, adns_query qu,
253 const char *fmt, ...) PRINTFFORMAT(4,5);
254 void adns__warn(adns_state ads, int serv, adns_query qu,
255 const char *fmt, ...) PRINTFFORMAT(4,5);
256 void adns__diag(adns_state ads, int serv, adns_query qu,
257 const char *fmt, ...) PRINTFFORMAT(4,5);
259 int adns__vbuf_ensure(vbuf *vb, int want);
260 int adns__vbuf_appendstr(vbuf *vb, const char *data); /* does not include nul */
261 int adns__vbuf_append(vbuf *vb, const byte *data, int len);
262 /* 1=>success, 0=>realloc failed */
263 void adns__vbuf_appendq(vbuf *vb, const byte *data, int len);
264 void adns__vbuf_init(vbuf *vb);
265 void adns__vbuf_free(vbuf *vb);
267 const char *adns__diag_domain(adns_state ads, int serv, adns_query qu,
268 vbuf *vb, const byte *dgram, int dglen, int cbyte);
269 /* Unpicks a domain in a datagram and returns a string suitable for
270 * printing it as. Never fails - if an error occurs, it will
271 * return some kind of string describing the error.
273 * serv may be -1 and qu may be 0. vb must have been initialised,
274 * and will be left in an arbitrary consistent state.
276 * Returns either vb->buf, or a pointer to a string literal. Do not modify
277 * vb before using the return value.
280 void adns__isort(void *array, int nobjs, int sz, void *tempbuf,
281 int (*needswap)(const void *a, const void *b));
282 /* Does an insertion sort of array which must contain nobjs objects
283 * each sz bytes long. tempbuf must point to a buffer at least
284 * sz bytes long. needswap should return !0 if a>b (strictly, ie
285 * wrong order) 0 if a<=b (ie, order is fine).
288 /* From transmit.c: */
290 adns_status adns__mkquery(adns_state ads, vbuf *vb, int *id_r,
291 const char *owner, int ol,
292 const typeinfo *typei, adns_queryflags flags);
293 /* Assembles a query packet in vb, and returns id at *id_r. */
295 adns_status adns__mkquery_frdgram(adns_state ads, vbuf *vb, int *id_r,
296 const byte *qd_dgram, int qd_dglen, int qd_begin,
297 adns_rrtype type, adns_queryflags flags);
298 /* Same as adns__mkquery, but takes the owner domain from an existing datagram.
299 * That domain must be correct and untruncated.
302 void adns__query_tcp(adns_query qu, struct timeval now);
303 /* Query must be in state tcpwait/timew; it will be moved to a new state
304 * if possible and no further processing can be done on it for now.
305 * (Resulting state is one of tcpwait/timew (if server not connected),
306 * tcpsent/timew, child/childw or done/output.)
308 * adns__tcp_tryconnect should already have been called - _tcp
309 * will only use an existing connection (if there is one), which it
310 * may break. If the conn list lost then the caller is responsible for any
311 * reestablishment and retry.
314 void adns__query_udp(adns_query qu, struct timeval now);
315 /* Query must be in state udp/NONE; it will be moved to a new state,
316 * and no further processing can be done on it for now.
317 * (Resulting state is one of udp/timew, tcpwait/timew (if server not connected),
318 * tcpsent/timew, child/childw or done/output.)
323 int adns__internal_submit(adns_state ads, adns_query *query_r,
324 const typeinfo *typei, vbuf *qumsg_vb, int id,
325 adns_queryflags flags, struct timeval now,
326 adns_status failstat, const qcontext *ctx);
327 /* Submits a query (for internal use, called during external submits).
329 * The new query is returned in *query_r, or we return adns_s_nomemory.
331 * The query datagram should already have been assembled in qumsg_vb;
332 * the memory for it is _taken over_ by this routine whether it
333 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
335 * If failstat is nonzero then if we are successful in creating the query
336 * it is immediately failed with code failstat (but _submit still succeds).
338 * ctx is copied byte-for-byte into the query.
341 void *adns__alloc_interim(adns_query qu, size_t sz);
342 /* Allocates some memory, and records which query it came from
343 * and how much there was.
345 * If an error occurs in the query, all its memory is simply freed.
347 * If the query succeeds, one large buffer will be made which is
348 * big enough for all these allocations, and then adns__alloc_final
349 * will get memory from this buffer.
351 * _alloc_interim can fail (and return 0).
352 * The caller must ensure that the query is failed.
354 * adns__alloc_interim_{only,fail}(qu,0) will not return 0,
355 * but it will not necessarily return a distinct pointer each time.
358 void *adns__alloc_mine(adns_query qu, size_t sz);
359 /* Like _interim, but does not record the length for later
360 * copying into the answer. This just ensures that the memory
361 * will be freed when we're done with the query.
364 void *adns__alloc_final(adns_query qu, size_t sz);
365 /* Cannot fail, and cannot return 0.
368 void adns__makefinal_block(adns_query qu, void **blpp, size_t sz);
369 void adns__makefinal_str(adns_query qu, char **strp);
371 void adns__reset_cnameonly(adns_query qu);
372 /* Resets all of the memory management stuff etc. to
373 * take account of only the CNAME. Used when we find an error somewhere
374 * and want to just report the error (with perhaps CNAME info), and also
375 * when we're halfway through RRs in a datagram and discover that we
376 * need to retry the query.
379 void adns__query_done(adns_query qu);
380 void adns__query_fail(adns_query qu, adns_status stat);
384 void adns__procdgram(adns_state ads, const byte *dgram, int len,
385 int serv, struct timeval now);
389 const typeinfo *adns__findtype(adns_rrtype type);
398 int dglen, max, cbyte, namelen;
402 void adns__findlabel_start(findlabel_state *fls, adns_state ads,
403 int serv, adns_query qu,
404 const byte *dgram, int dglen, int max,
405 int dmbegin, int *dmend_rlater);
406 /* Finds labels in a domain in a datagram.
408 * Call this routine first.
409 * dmend_rlater may be null. ads (and of course fls) may not be.
410 * serv may be -1, qu may be null - they are for error reporting.
413 adns_status adns__findlabel_next(findlabel_state *fls, int *lablen_r, int *labstart_r);
414 /* Then, call this one repeatedly.
416 * It will return adns_s_ok if all is well, and tell you the length
417 * and start of successive labels. labstart_r may be null, but
418 * lablen_r must not be.
420 * After the last label, it will return with *lablen_r zero.
421 * Do not then call it again; instead, just throw away the findlabel_state.
423 * *dmend_rlater will have been set to point to the next part of
424 * the datagram after the label (or after the uncompressed part,
425 * if compression was used). *namelen_rlater will have been set
426 * to the length of the domain name (total length of labels plus
427 * 1 for each intervening dot).
429 * If the datagram appears to be truncated, *lablen_r will be -1.
430 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
431 * Do not call _next again.
433 * There may also be errors, in which case *dmend_rlater,
434 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
435 * Do not then call findlabel_next again.
442 adns_status adns__parse_domain(adns_state ads, int serv, adns_query qu,
443 vbuf *vb, parsedomain_flags flags,
444 const byte *dgram, int dglen, int *cbyte_io, int max);
445 /* vb must already have been initialised; it will be reset if necessary.
446 * If there is truncation, vb->used will be set to 0; otherwise
447 * (if there is no error) vb will be null-terminated.
448 * If there is an error vb and *cbyte_io may be left indeterminate.
450 * serv may be -1 and qu may be 0 - they are used for error reporting only.
453 adns_status adns__findrr(adns_query qu, int serv,
454 const byte *dgram, int dglen, int *cbyte_io,
455 int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
456 int *ownermatchedquery_r);
457 /* Finds the extent and some of the contents of an RR in a datagram
458 * and does some checks. The datagram is *dgram, length dglen, and
459 * the RR starts at *cbyte_io (which is updated afterwards to point
460 * to the end of the RR).
462 * The type, class and RRdata length and start are returned iff
463 * the corresponding pointer variables are not null. type_r and
464 * class_r may not be null.
466 * If ownermatchedquery_r != 0 then the owner domain of this
467 * RR will be compared with that in the query (or, if the query
468 * has gone to a CNAME lookup, with the canonical name).
469 * In this case, *ownermatchedquery_r will be set to 0 or 1.
470 * The query datagram (or CNAME datagram) MUST be valid and not truncated.
472 * If there is truncation then *type_r will be set to -1 and
473 * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
476 * qu must obviously be non-null.
478 * If an error is returned then *type_r will be undefined too.
481 static adns_status findrr_anychk(adns_query qu, int serv,
482 const byte *dgram, int dglen, int *cbyte_io,
483 int *type_r, int *class_r, int *rdlen_r, int *rdstart_r,
484 const byte *eo_dgram, int eo_dglen, int eo_cbyte,
486 /* Like adns__findrr_checked, except that the datagram and
487 * owner to compare with can be specified explicitly.
489 * If the caller thinks they know what the owner of the RR ought to
490 * be they can pass in details in eo_*: this is another (or perhaps
491 * the same datagram), and a pointer to where the putative owner
492 * starts in that datagram. In this case *eo_matched_r will be set
493 * to 1 if the datagram matched or 0 if it did not. Either
494 * both eo_dgram and eo_matched_r must both be non-null, or they
495 * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
496 * The eo datagram and contained owner domain MUST be valid and
500 int vbuf__append_quoted1035(vbuf *vb, const byte *buf, int len);
504 void adns__tcp_broken(adns_state ads, const char *what, const char *why);
505 void adns__tcp_tryconnect(adns_state ads, struct timeval now);
507 void adns__autosys(adns_state ads, struct timeval now);
508 /* Make all the system calls we want to if the application wants us to. */
510 /* Useful static inline functions: */
512 static inline void timevaladd(struct timeval *tv_io, long ms) {
516 tmp.tv_usec += (ms%1000)*1000000;
517 tmp.tv_sec += ms/1000;
518 if (tmp.tv_usec >= 1000000) { tmp.tv_sec++; tmp.tv_usec -= 1000; }
522 static inline int ctype_whitespace(int c) { return c==' ' || c=='\n' || c=='\t'; }
523 static inline int ctype_digit(int c) { return c>='0' && c<='9'; }
524 static inline int ctype_alpha(int c) {
525 return (c >= 'a' && c <= 'z') || (c >= 'A' || c <= 'Z');
530 #define MEM_ROUND(sz) \
531 (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
532 * sizeof(union maxalign) )
534 #define LIST_INIT(list) ((list).head= (list).tail= 0)
536 #define LIST_UNLINK_PART(list,node,part) \
538 if ((node)->back) (node)->back->part next= (node)->part next; \
539 else (list).head= (node)->part next; \
540 if ((node)->next) (node)->next->part back= (node)->part back; \
541 else (list).tail= (node)->part back; \
544 #define LIST_LINK_TAIL_PART(list,node,part) \
546 (node)->part next= 0; \
547 (node)->part back= (list).tail; \
548 if ((list).tail) (list).tail->part next= (node); else (list).part head= (node); \
549 (list).tail= (node); \
552 #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
553 #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
555 #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff)
556 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
557 #define GET_W(cb,tv) ((tv)=0, (tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))