3a6f063179f39dd1a362aaf4670f918811a5e8c0
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
9 * Copyright (C) 1997-2000,2003,2006 Ian Jackson
10 * Copyright (C) 1999-2000,2003,2006 Tony Finch
11 * Copyright (C) 1991 Massachusetts Institute of Technology
12 * (See the file INSTALL for full details.)
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 #ifndef ADNS_INTERNAL_H_INCLUDED
30 #define ADNS_INTERNAL_H_INCLUDED
33 typedef unsigned char byte
;
46 #define ADNS_FEATURE_MANYAF
50 #ifdef ADNS_REGRESS_TEST
51 # include "hredirect.h"
54 /* Configuration and constants */
57 #define MAXSORTLIST 15
58 #define UDPMAXRETRIES 15
59 #define UDPRETRYMS 2000
60 #define TCPWAITMS 30000
61 #define TCPCONNMS 14000
62 #define TCPIDLEMS 30000
63 #define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */
66 #define DNS_MAXUDP 512
67 #define DNS_MAXLABEL 63
68 #define DNS_MAXDOMAIN 255
69 #define DNS_HDRSIZE 12
70 #define DNS_IDOFFSET 0
71 #define DNS_CLASS_IN 1
73 #define DNS_INADDR_ARPA "in-addr", "arpa"
74 #define DNS_IP6_ARPA "ip6", "arpa"
76 #define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED
78 /* Some preprocessor hackery */
80 #define GLUE(x, y) GLUE_(x, y)
81 #define GLUE_(x, y) x##y
83 /* C99 macro `...' must match at least one argument, so the naive definition
84 * `#define CAR(car, ...) car' won't work. But it's easy to arrange for the
85 * tail to be nonempty if we're just going to discard it anyway. */
86 #define CAR(...) CAR_(__VA_ARGS__, _)
87 #define CAR_(car, ...) car
89 /* Extracting the tail of an argument list is rather more difficult. The
90 * following trick is based on one by Laurent Deniau to count the number of
91 * arguments to a macro, simplified in two ways: (a) it only handles up to
92 * eight arguments, and (b) it only needs to distinguish the one-argument
93 * case from many arguments. */
94 #define CDR(...) CDR_(__VA_ARGS__, m, m, m, m, m, m, m, 1, _)(__VA_ARGS__)
95 #define CDR_(_1, _2, _3, _4, _5, _6, _7, _8, n, ...) CDR_##n
97 #define CDR_m(_, ...) __VA_ARGS__
103 } consistency_checks
;
115 adns__qf_addr_answer
= 0x01000000,/* addr query received an answer */
116 adns__qf_addr_cname
= 0x02000000 /* addr subquery performed on cname */
119 /* Shared data structures */
131 int dglen
, nsstart
, nscount
, arcount
;
135 #define NREVDOMAINS 2 /* keep in sync with addrfam! */
136 struct revparse_state
{
137 unsigned map
; /* which domains are still live */
138 byte ipv
[NREVDOMAINS
][32]; /* address components so far */
141 union checklabel_state
{
142 struct revparse_state ptr
;
147 void (*callback
)(adns_query parent
, adns_query child
);
151 adns_rrtype rev_rrtype
;
157 } tinfo
; /* type-specific state for the query itself: zero-init if you
158 * don't know better. */
161 adns_rr_hostaddr
*hostaddr
;
162 } pinfo
; /* state for use by parent's callback function */
165 typedef struct typeinfo
{
171 void (*makefinal
)(adns_query qu
, void *data
);
172 /* Change memory management of *data.
173 * Previously, used alloc_interim, now use alloc_final.
176 adns_status (*convstring
)(vbuf
*vb
, const void *data
);
177 /* Converts the RR data to a string representation in vbuf.
178 * vbuf will be appended to (it must have been initialised),
179 * and will not be null-terminated by convstring.
182 adns_status (*parse
)(const parseinfo
*pai
, int cbyte
,
183 int max
, void *store_r
);
184 /* Parse one RR, in dgram of length dglen, starting at cbyte and
185 * extending until at most max.
187 * The RR should be stored at *store_r, of length qu->typei->getrrsz().
189 * If there is an overrun which might indicate truncation, it should set
190 * *rdstart to -1; otherwise it may set it to anything else positive.
192 * nsstart is the offset of the authority section.
195 int (*diff_needswap
)(adns_state ads
,const void *datap_a
,const void *datap_b
);
196 /* Returns !0 if RR a should be strictly after RR b in the sort order,
197 * 0 otherwise. Must not fail.
200 adns_status (*checklabel
)(adns_state ads
, adns_queryflags flags
,
201 union checklabel_state
*cls
, qcontext
*ctx
,
202 int labnum
, const char *dgram
,
203 int labstart
, int lablen
);
204 /* Check a label from the query domain string. The label is not
205 * necessarily null-terminated. The hook can refuse the query's submission
206 * by returning a nonzero status. State can be stored in *cls between
207 * calls, and useful information can be stashed in ctx->tinfo, to be stored
208 * with the query (e.g., it will be available to the parse hook). This
209 * hook can detect a first call because labnum is zero, and a final call
210 * because lablen is zero.
213 void (*postsort
)(adns_state ads
, void *array
, int nrrs
,int rrsz
,
214 const struct typeinfo
*typei
);
215 /* Called immediately after the RRs have been sorted, and may rearrange
216 * them. (This is really for the benefit of SRV's bizarre weighting
217 * stuff.) May be 0 to mean nothing needs to be done.
220 int (*getrrsz
)(const struct typeinfo
*typei
, adns_rrtype type
);
221 /* Return the output resource-record element size; if this is null, then
222 * the rrsz member can be used.
225 void (*query_send
)(adns_query qu
, struct timeval now
);
226 /* Send the query to nameservers, and hook it into the appropriate queue.
227 * Normal behaviour is to call adns__query_send, but this can be overridden
228 * for special effects.
232 adns_status
adns__ckl_hostname(adns_state ads
, adns_queryflags flags
,
233 union checklabel_state
*cls
,
234 qcontext
*ctx
, int labnum
,
235 const char *dgram
, int labstart
, int lablen
);
236 /* implemented in query.c, used by types.c as default
237 * and as part of implementation for some fancier types
238 * doesn't require any state */
240 typedef struct allocnode
{
241 struct allocnode
*next
, *back
;
256 enum { query_tosend
, query_tcpw
, query_childw
, query_done
} state
;
257 adns_query back
, next
, parent
;
258 struct { adns_query head
, tail
; } children
;
259 struct { adns_query back
, next
; } siblings
;
260 struct { allocnode
*head
, *tail
; } allocations
;
261 int interim_allocd
, preserved_allocd
;
262 void *final_allocspace
;
264 const typeinfo
*typei
;
269 /* General-purpose messing-about buffer.
270 * Wherever a `big' interface is crossed, this may be corrupted/changed
271 * unless otherwise specified.
275 /* This is allocated when a query is submitted, to avoid being unable
276 * to relate errors to queries if we run out of memory. During
277 * query processing status, rrs is 0. cname is set if
278 * we found a cname (this corresponds to cname_dgram in the query
279 * structure). type is set from the word go. nrrs and rrs
280 * are set together, when we find how many rrs there are.
281 * owner is set during querying unless we're doing searchlist,
282 * in which case it is set only when we find an answer.
286 int cname_dglen
, cname_begin
;
287 /* If non-0, has been allocated using . */
290 int search_origlen
, search_pos
, search_doneabs
;
291 /* Used by the searching algorithm. The query domain in textual form
292 * is copied into the vbuf, and _origlen set to its length. Then
293 * we walk the searchlist, if we want to. _pos says where we are
294 * (next entry to try), and _doneabs says whether we've done the
295 * absolute query yet (0=not yet, 1=done, -1=must do straight away,
296 * but not done yet). If flags doesn't have adns_qf_search then
297 * the vbuf is initialised but empty and everything else is zero.
300 int id
, flags
, retries
;
302 unsigned long udpsent
; /* bitmap indexed by server */
303 struct timeval timeout
;
304 time_t expires
; /* Earliest expiry time of any record we used. */
310 * state Queue child id nextudpserver udpsent tcpfailed
312 * tosend NONE null >=0 0 zero zero
313 * tosend udpw null >=0 any nonzero zero
314 * tosend NONE null >=0 any nonzero zero
316 * tcpw tcpw null >=0 irrelevant any any
318 * child childw set >=0 irrelevant irrelevant irrelevant
319 * child NONE null >=0 irrelevant irrelevant irrelevant
320 * done output null -1 irrelevant irrelevant irrelevant
322 * Queries are only not on a queue when they are actually being processed.
323 * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer)
324 * iff the tcp connection is in state server_ok.
326 * Internal queries (from adns__submit_internal) end up on intdone
327 * instead of output, and the callbacks are made on the way out of
328 * adns, to avoid reentrancy hazards.
330 * +------------------------+
331 * START -----> | tosend/NONE |
332 * +------------------------+
334 * too big for UDP / UDP timeout \ \ send via UDP
335 * send via TCP / more retries \ \
336 * when conn'd / desired \ \
339 * +-----------+ +-------------+
340 * | tcpw/tcpw | ________ | tosend/udpw |
341 * +-----------+ \ +-------------+
342 * | | | UDP timeout | |
345 * \ | TCP died | desired | |
347 * \ \ servers | TCP / |
348 * \ \ to try | timeout / |
350 * reply \ _| +------------------+ / reply
351 * \ | done/output FAIL | /
352 * \ +------------------+ /
355 * (..... got reply ....)
357 * need child query/ies / \ no child query
360 * +---------------+ +----------------+
361 * | childw/childw | ----------------> | done/output OK |
362 * +---------------+ children done +----------------+
366 struct query_queue
{ adns_query head
, tail
; };
371 adns_initflags iflags
;
372 adns_logcallbackfn
*logfn
;
375 struct query_queue udpw
, tcpw
, childw
, output
, intdone
;
376 adns_query forallnext
;
377 int nextid
, tcpsocket
;
378 struct udpsocket
{ int af
; int fd
; } udpsocket
[MAXUDP
];
380 vbuf tcpsend
, tcprecv
;
381 int nservers
, nsortlist
, nsearchlist
, searchndots
, tcpserver
, tcprecv_skip
;
382 enum adns__tcpstate
{
383 server_disconnected
, server_connecting
,
384 server_ok
, server_broken
386 struct timeval tcptimeout
;
387 /* This will have tv_sec==0 if it is not valid. It will always be
388 * valid if tcpstate _connecting. When _ok, it will be nonzero if
389 * we are idle (ie, tcpw queue is empty), in which case it is the
390 * absolute time when we will close the connection.
392 struct sigaction stdsigpipe
;
394 struct pollfd pollfds_buf
[MAX_POLLFDS
];
395 adns_rr_addr servers
[MAXSERVERS
];
397 adns_sockaddr base
, mask
;
398 } sortlist
[MAXSORTLIST
];
400 unsigned short rand48xsubi
[3];
403 /* From addrfam.c: */
405 extern int adns__addrs_equal_raw(const struct sockaddr
*a
,
406 int bf
, const void *b
);
407 /* Returns nonzero a's family is bf and a's protocol address field
408 * refers to the same protocol address as that stored at ba.
411 extern int adns__addrs_equal(const adns_sockaddr
*a
,
412 const adns_sockaddr
*b
);
413 /* Returns nonzero if the two refer to the same protocol address
414 * (disregarding port, IPv6 scope, etc).
417 extern int adns__sockaddrs_equal(const struct sockaddr
*sa
,
418 const struct sockaddr
*sb
);
419 /* Return nonzero if the two socket addresses are equal (in all significant
423 extern int adns__addr_width(int af
);
424 /* Return the width of addresses of family af, in bits. */
426 extern void adns__prefix_mask(adns_sockaddr
*sa
, int len
);
427 /* Stores in sa's protocol address field an address mask for address
428 * family af, whose first len bits are set and the remainder are
429 * clear. On entry, sa's af field must be set. This is what you want
430 * for converting a prefix length into a netmask.
433 extern int adns__guess_prefix_length(const adns_sockaddr
*addr
);
434 /* Given a network base address, guess the appropriate prefix length based on
435 * the appropriate rules for the address family (e.g., for IPv4, this uses
436 * the old address classes).
439 extern int adns__addr_matches(int af
, const void *addr
,
440 const adns_sockaddr
*base
,
441 const adns_sockaddr
*mask
);
442 /* Return nonzero if the protocol address specified by af and addr
443 * lies within the network specified by base and mask.
446 extern void adns__addr_inject(const void *a
, adns_sockaddr
*sa
);
447 /* Injects the protocol address *a into the socket adress sa. Assumes
448 * that sa->sa_family is already set correctly.
451 extern const void *adns__sockaddr_addr(const struct sockaddr
*sa
);
452 /* Returns the address of the protocol address field in sa.
455 char *adns__sockaddr_ntoa(const struct sockaddr
*sa
, char *buf
);
456 /* Convert sa to a string, and write it to buf, which must be at least
457 * ADNS_ADDR2TEXT_BUFLEN bytes long (unchecked). Return buf; can't fail.
460 extern int adns__make_reverse_domain(const struct sockaddr
*sa
,
462 char **buf_io
, size_t bufsz
,
464 /* Construct a reverse domain string, given a socket address and a parent
465 * zone. If zone is null, then use the standard reverse-lookup zone for the
466 * address family. If the length of the resulting string is no larger than
467 * bufsz, then the result is stored starting at *buf_io; otherwise a new
468 * buffer is allocated is used, and a pointer to it is stored in both *buf_io
469 * and *buf_free_r (the latter of which should be null on entry). If
470 * something goes wrong, then an errno value is returned: ENOSYS if the
471 * address family of sa isn't recognized, or ENOMEM if the attempt to
472 * allocate an output buffer failed.
475 extern bool adns__revparse_label(struct revparse_state
*rps
, int labnum
,
477 int labstart
, int lablen
);
478 /* Parse a label in a reverse-domain name, given its index labnum (starting
479 * from zero), a pointer to its contents (which need not be null-terminated),
480 * and its length. The state in *rps is initialized implicitly when labnum
483 * Returns 1 if the parse is proceeding successfully, 0 if the domain
484 * name is definitely invalid and the parse must be abandoned.
487 extern bool adns__revparse_done(struct revparse_state
*rps
,
488 const char *dgram
, int nlabels
,
489 adns_rrtype
*rrtype_r
, adns_sockaddr
*addr_r
);
490 /* Finishes parsing a reverse-domain name, given the total number of
491 * labels in the name. On success, fills in the af and protocol
492 * address in *addr_r, and the forward query type in *rrtype_r
493 * (because that turns out to be useful). Returns 1 if the parse
499 int adns__setnonblock(adns_state ads
, int fd
); /* => errno value */
501 /* From general.c: */
503 void adns__vlprintf(adns_state ads
, const char *fmt
, va_list al
);
504 void adns__lprintf(adns_state ads
, const char *fmt
,
505 ...) PRINTFFORMAT(2,3);
507 void adns__vdiag(adns_state ads
, const char *pfx
, adns_initflags prevent
,
508 int serv
, adns_query qu
, const char *fmt
, va_list al
);
510 void adns__debug(adns_state ads
, int serv
, adns_query qu
,
511 const char *fmt
, ...) PRINTFFORMAT(4,5);
512 void adns__warn(adns_state ads
, int serv
, adns_query qu
,
513 const char *fmt
, ...) PRINTFFORMAT(4,5);
514 void adns__diag(adns_state ads
, int serv
, adns_query qu
,
515 const char *fmt
, ...) PRINTFFORMAT(4,5);
517 int adns__vbuf_ensure(vbuf
*vb
, int want
);
518 int adns__vbuf_appendstr(vbuf
*vb
, const char *data
); /* doesn't include nul */
519 int adns__vbuf_append(vbuf
*vb
, const byte
*data
, int len
);
520 /* 1=>success, 0=>realloc failed */
521 void adns__vbuf_appendq(vbuf
*vb
, const byte
*data
, int len
);
522 void adns__vbuf_init(vbuf
*vb
);
523 void adns__vbuf_free(vbuf
*vb
);
525 const char *adns__diag_domain(adns_state ads
, int serv
, adns_query qu
,
527 const byte
*dgram
, int dglen
, int cbyte
);
528 /* Unpicks a domain in a datagram and returns a string suitable for
529 * printing it as. Never fails - if an error occurs, it will
530 * return some kind of string describing the error.
532 * serv may be -1 and qu may be 0. vb must have been initialised,
533 * and will be left in an arbitrary consistent state.
535 * Returns either vb->buf, or a pointer to a string literal. Do not modify
536 * vb before using the return value.
539 int adns__getrrsz_default(const typeinfo
*typei
, adns_rrtype type
);
540 /* Default function for the `getrrsz' type hook; returns the `fixed_rrsz'
541 * value from the typeinfo entry.
544 void adns__isort(void *array
, int nobjs
, int sz
, void *tempbuf
,
545 int (*needswap
)(void *context
, const void *a
, const void *b
),
547 /* Does an insertion sort of array which must contain nobjs objects
548 * each sz bytes long. tempbuf must point to a buffer at least
549 * sz bytes long. needswap should return !0 if a>b (strictly, ie
550 * wrong order) 0 if a<=b (ie, order is fine).
553 void adns__sigpipe_protect(adns_state
);
554 void adns__sigpipe_unprotect(adns_state
);
555 /* If SIGPIPE protection is not disabled, will block all signals except
556 * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.)
557 * Each call to _protect must be followed by a call to _unprotect before
558 * any significant amount of code gets to run, since the old signal mask
559 * is stored in the adns structure.
562 /* From transmit.c: */
564 adns_status
adns__mkquery(adns_state ads
, vbuf
*vb
, int *id_r
,
565 const char *owner
, int ol
,
566 const typeinfo
*typei
, adns_rrtype type
,
567 adns_queryflags flags
);
568 /* Assembles a query packet in vb. A new id is allocated and returned.
571 adns_status
adns__mkquery_frdgram(adns_state ads
, vbuf
*vb
, int *id_r
,
572 const byte
*qd_dgram
, int qd_dglen
,
574 adns_rrtype type
, adns_queryflags flags
);
575 /* Same as adns__mkquery, but takes the owner domain from an existing datagram.
576 * That domain must be correct and untruncated.
579 void adns__querysend_tcp(adns_query qu
, struct timeval now
);
580 /* Query must be in state tcpw/tcpw; it will be sent if possible and
581 * no further processing can be done on it for now. The connection
582 * might be broken, but no reconnect will be attempted.
585 struct udpsocket
*adns__udpsocket_by_af(adns_state ads
, int af
);
586 /* Find the UDP socket structure in ads which has the given address family.
587 * Return null if there isn't one.
589 * This is used during initialization, so ads is only partially filled in.
590 * The requirements are that nudp is set, and that udpsocket[i].af are
591 * defined for 0<=i<nudp.
594 void adns__query_send(adns_query qu
, struct timeval now
);
595 /* Query must be in state tosend/NONE; it will be moved to a new state,
596 * and no further processing can be done on it for now.
597 * (Resulting state is one of udp/timew, tcpwait/timew (if server not
598 * connected), tcpsent/timew, child/childw or done/output.)
599 * __query_send may decide to use either UDP or TCP depending whether
600 * _qf_usevc is set (or has become set) and whether the query is too
606 adns_status
adns__internal_submit(adns_state ads
, adns_query
*query_r
,
608 const typeinfo
*typei
, adns_rrtype type
,
609 vbuf
*qumsg_vb
, int id
,
610 adns_queryflags flags
, struct timeval now
,
612 /* Submits a query (for internal use, called during external submits).
614 * The new query is returned in *query_r, or we return adns_s_nomemory.
616 * The query datagram should already have been assembled in qumsg_vb;
617 * the memory for it is _taken over_ by this routine whether it
618 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
620 * *ctx is copied byte-for-byte into the query. Before doing this, its tinfo
621 * field may be modified by type hooks.
623 * When the child query is done, ctx->callback will be called. The
624 * child will already have been taken off both the global list of
625 * queries in ads and the list of children in the parent. The child
626 * will be freed when the callback returns. The parent will have been
627 * taken off the global childw queue.
629 * The callback should either call adns__query_done, if it is
630 * complete, or adns__query_fail, if an error has occurred, in which
631 * case the other children (if any) will be cancelled. If the parent
632 * has more unfinished children (or has just submitted more) then the
633 * callback may choose to wait for them - it must then put the parent
634 * back on the childw queue.
637 void adns__search_next(adns_state ads
, adns_query qu
, struct timeval now
);
638 /* Walks down the searchlist for a query with adns_qf_search.
639 * The query should have just had a negative response, or not had
640 * any queries sent yet, and should not be on any queue.
641 * The query_dgram if any will be freed and forgotten and a new
642 * one constructed from the search_* members of the query.
644 * Cannot fail (in case of error, calls adns__query_fail).
647 void *adns__alloc_interim(adns_query qu
, size_t sz
);
648 void *adns__alloc_preserved(adns_query qu
, size_t sz
);
649 /* Allocates some memory, and records which query it came from
650 * and how much there was.
652 * If an error occurs in the query, all the memory from _interim is
653 * simply freed. If the query succeeds, one large buffer will be made
654 * which is big enough for all these allocations, and then
655 * adns__alloc_final will get memory from this buffer.
657 * _alloc_interim can fail (and return 0).
658 * The caller must ensure that the query is failed.
660 * The memory from _preserved is is kept and transferred into the
661 * larger buffer - unless we run out of memory, in which case it too
662 * is freed. When you use _preserved you have to add code to the
663 * x_nomem error exit case in adns__makefinal_query to clear out the
664 * pointers you made to those allocations, because that's when they're
665 * thrown away; you should also make a note in the declaration of
666 * those pointer variables, to note that they are _preserved rather
667 * than _interim. If they're in the answer, note it here:
668 * answer->cname and answer->owner are _preserved.
671 void adns__transfer_interim(adns_query from
, adns_query to
, void *block
);
672 /* Transfers an interim allocation from one query to another, so that
673 * the `to' query will have room for the data when we get to makefinal
674 * and so that the free will happen when the `to' query is freed
675 * rather than the `from' query.
677 * It is legal to call adns__transfer_interim with a null pointer; this
680 * _transfer_interim also ensures that the expiry time of the `to' query
681 * is no later than that of the `from' query, so that child queries'
682 * TTLs get inherited by their parents.
685 void adns__free_interim(adns_query qu
, void *p
);
686 /* Forget about a block allocated by adns__alloc_interim.
689 void *adns__alloc_mine(adns_query qu
, size_t sz
);
690 /* Like _interim, but does not record the length for later
691 * copying into the answer. This just ensures that the memory
692 * will be freed when we're done with the query.
695 void *adns__alloc_final(adns_query qu
, size_t sz
);
696 /* Cannot fail, and cannot return 0.
699 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
);
700 void adns__makefinal_str(adns_query qu
, char **strp
);
702 void adns__reset_preserved(adns_query qu
);
703 /* Resets all of the memory management stuff etc. to take account of
704 * only the _preserved stuff from _alloc_preserved. Used when we find
705 * an error somewhere and want to just report the error (with perhaps
706 * CNAME, owner, etc. info), and also when we're halfway through RRs
707 * in a datagram and discover that we need to retry the query.
710 void adns__cancel(adns_query qu
);
711 void adns__query_done(adns_query qu
);
712 void adns__query_fail(adns_query qu
, adns_status stat
);
713 void adns__cancel_children(adns_query qu
);
715 void adns__returning(adns_state ads
, adns_query qu
);
716 /* Must be called before returning from adns any time that we have
717 * progressed (including made, finished or destroyed) queries.
719 * Might reenter adns via internal query callbacks, so
720 * external-faciing functions which call adns__returning should
721 * normally be avoided in internal code. */
725 void adns__procdgram(adns_state ads
, const byte
*dgram
, int len
,
726 int serv
, int viatcp
, struct timeval now
);
727 /* This function is allowed to cause new datagrams to be constructed
728 * and sent, or even new queries to be started. However,
729 * query-sending functions are not allowed to call any general event
730 * loop functions in case they accidentally call this.
732 * Ie, receiving functions may call sending functions.
733 * Sending functions may NOT call receiving functions.
738 const typeinfo
*adns__findtype(adns_rrtype type
);
747 int dglen
, max
, cbyte
, namelen
;
751 void adns__findlabel_start(findlabel_state
*fls
, adns_state ads
,
752 int serv
, adns_query qu
,
753 const byte
*dgram
, int dglen
, int max
,
754 int dmbegin
, int *dmend_rlater
);
755 /* Finds labels in a domain in a datagram.
757 * Call this routine first.
758 * dmend_rlater may be null. ads (and of course fls) may not be.
759 * serv may be -1, qu may be null - they are for error reporting.
762 adns_status
adns__findlabel_next(findlabel_state
*fls
,
763 int *lablen_r
, int *labstart_r
);
764 /* Then, call this one repeatedly.
766 * It will return adns_s_ok if all is well, and tell you the length
767 * and start of successive labels. labstart_r may be null, but
768 * lablen_r must not be.
770 * After the last label, it will return with *lablen_r zero.
771 * Do not then call it again; instead, just throw away the findlabel_state.
773 * *dmend_rlater will have been set to point to the next part of
774 * the datagram after the label (or after the uncompressed part,
775 * if compression was used). *namelen_rlater will have been set
776 * to the length of the domain name (total length of labels plus
777 * 1 for each intervening dot).
779 * If the datagram appears to be truncated, *lablen_r will be -1.
780 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
781 * Do not call _next again.
783 * There may also be errors, in which case *dmend_rlater,
784 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
785 * Do not then call findlabel_next again.
792 adns_status
adns__parse_domain(adns_state ads
, int serv
, adns_query qu
,
793 vbuf
*vb
, parsedomain_flags flags
,
794 const byte
*dgram
, int dglen
, int *cbyte_io
,
796 /* vb must already have been initialised; it will be reset if necessary.
797 * If there is truncation, vb->used will be set to 0; otherwise
798 * (if there is no error) vb will be null-terminated.
799 * If there is an error vb and *cbyte_io may be left indeterminate.
801 * serv may be -1 and qu may be 0 - they are used for error reporting only.
804 adns_status
adns__parse_domain_more(findlabel_state
*fls
, adns_state ads
,
805 adns_query qu
, vbuf
*vb
,
806 parsedomain_flags flags
,
808 /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state,
809 * for continuing an existing domain or some such of some kind. Also, unlike
810 * _parse_domain, the domain data will be appended to vb, rather than replacing
811 * the existing contents.
814 adns_status
adns__findrr(adns_query qu
, int serv
,
815 const byte
*dgram
, int dglen
, int *cbyte_io
,
816 int *type_r
, int *class_r
, unsigned long *ttl_r
,
817 int *rdlen_r
, int *rdstart_r
,
818 int *ownermatchedquery_r
);
819 /* Finds the extent and some of the contents of an RR in a datagram
820 * and does some checks. The datagram is *dgram, length dglen, and
821 * the RR starts at *cbyte_io (which is updated afterwards to point
822 * to the end of the RR).
824 * The type, class, TTL and RRdata length and start are returned iff
825 * the corresponding pointer variables are not null. type_r, class_r
826 * and ttl_r may not be null. The TTL will be capped.
828 * If ownermatchedquery_r != 0 then the owner domain of this
829 * RR will be compared with that in the query (or, if the query
830 * has gone to a CNAME lookup, with the canonical name).
831 * In this case, *ownermatchedquery_r will be set to 0 or 1.
832 * The query datagram (or CNAME datagram) MUST be valid and not truncated.
834 * If there is truncation then *type_r will be set to -1 and
835 * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
838 * qu must obviously be non-null.
840 * If an error is returned then *type_r will be undefined too.
843 adns_status
adns__findrr_anychk(adns_query qu
, int serv
,
844 const byte
*dgram
, int dglen
, int *cbyte_io
,
845 int *type_r
, int *class_r
,
846 unsigned long *ttl_r
,
847 int *rdlen_r
, int *rdstart_r
,
848 const byte
*eo_dgram
, int eo_dglen
,
849 int eo_cbyte
, int *eo_matched_r
);
850 /* Like adns__findrr_checked, except that the datagram and
851 * owner to compare with can be specified explicitly.
853 * If the caller thinks they know what the owner of the RR ought to
854 * be they can pass in details in eo_*: this is another (or perhaps
855 * the same datagram), and a pointer to where the putative owner
856 * starts in that datagram. In this case *eo_matched_r will be set
857 * to 1 if the datagram matched or 0 if it did not. Either
858 * both eo_dgram and eo_matched_r must both be non-null, or they
859 * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
860 * The eo datagram and contained owner domain MUST be valid and
864 void adns__update_expires(adns_query qu
, unsigned long ttl
,
866 /* Updates the `expires' field in the query, so that it doesn't exceed
870 int vbuf__append_quoted1035(vbuf
*vb
, const byte
*buf
, int len
);
872 bool adns__labels_equal(const byte
*a
, int al
, const byte
*b
, int bl
);
876 void adns__tcp_broken(adns_state ads
, const char *what
, const char *why
);
877 /* what and why may be both 0, or both non-0. */
879 void adns__tcp_tryconnect(adns_state ads
, struct timeval now
);
881 void adns__autosys(adns_state ads
, struct timeval now
);
882 /* Make all the system calls we want to if the application wants us to.
883 * Must not be called from within adns internal processing functions,
884 * lest we end up in recursive descent !
887 void adns__must_gettimeofday(adns_state ads
, const struct timeval
**now_io
,
888 struct timeval
*tv_buf
);
889 /* Call with care - might reentrantly cause queries to be completed! */
891 int adns__pollfds(adns_state ads
, struct pollfd pollfds_buf
[MAX_POLLFDS
]);
892 void adns__fdevents(adns_state ads
,
893 const struct pollfd
*pollfds
, int npollfds
,
894 int maxfd
, const fd_set
*readfds
,
895 const fd_set
*writefds
, const fd_set
*exceptfds
,
896 struct timeval now
, int *r_r
);
897 int adns__internal_check(adns_state ads
,
898 adns_query
*query_io
,
899 adns_answer
**answer
,
902 void adns__timeouts(adns_state ads
, int act
,
903 struct timeval
**tv_io
, struct timeval
*tvbuf
,
905 /* If act is !0, then this will also deal with the TCP connection
906 * if previous events broke it or require it to be connected.
911 void adns__consistency(adns_state ads
, adns_query qu
, consistency_checks cc
);
913 /* Useful static inline functions: */
915 static inline int ctype_whitespace(int c
) {
916 return c
==' ' || c
=='\n' || c
=='\t';
918 static inline int ctype_digit(int c
) { return c
>='0' && c
<='9'; }
919 static inline int ctype_alpha(int c
) {
920 return (c
>= 'a' && c
<= 'z') || (c
>= 'A' && c
<= 'Z');
922 static inline int ctype_toupper(int c
) {
923 return ctype_alpha(c
) ?
(c
& ~32) : c
;
925 static inline int ctype_822special(int c
) {
926 return strchr("()<>@,;:\\\".[]",c
) != 0;
928 static inline int ctype_domainunquoted(int c
) {
929 return ctype_alpha(c
) || ctype_digit(c
) || (strchr("-_/+",c
) != 0);
932 static inline int errno_resources(int e
) { return e
==ENOMEM
|| e
==ENOBUFS
; }
936 #define MEM_ROUND(sz) \
937 (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
938 * sizeof(union maxalign) )
940 #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff)
941 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
942 #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))
943 #define GET_L(cb,tv) ( (tv)=0, \
944 (tv)|=(GETIL_B((cb))<<24), \
945 (tv)|=(GETIL_B((cb))<<16), \
946 (tv)|=(GETIL_B((cb))<<8), \