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
;
45 #define ADNS_FEATURE_MANYAF
49 #ifdef ADNS_REGRESS_TEST
50 # include "hredirect.h"
53 /* Configuration and constants */
56 #define MAXSORTLIST 15
57 #define UDPMAXRETRIES 15
58 #define UDPRETRYMS 2000
59 #define TCPWAITMS 30000
60 #define TCPCONNMS 14000
61 #define TCPIDLEMS 30000
62 #define MAXTTLBELIEVE (7*86400) /* any TTL > 7 days is capped */
65 #define DNS_MAXUDP 512
66 #define DNS_MAXLABEL 63
67 #define DNS_MAXDOMAIN 255
68 #define DNS_HDRSIZE 12
69 #define DNS_IDOFFSET 0
70 #define DNS_CLASS_IN 1
72 #define DNS_INADDR_ARPA "in-addr", "arpa"
73 #define DNS_IP6_ARPA "ip6", "arpa"
75 #define MAX_POLLFDS ADNS_POLLFDS_RECOMMENDED
77 /* Some preprocessor hackery */
79 #define GLUE(x, y) GLUE_(x, y)
80 #define GLUE_(x, y) x##y
82 /* C99 macro `...' must match at least one argument, so the naive definition
83 * `#define CAR(car, ...) car' won't work. But it's easy to arrange for the
84 * tail to be nonempty if we're just going to discard it anyway. */
85 #define CAR(...) CAR_(__VA_ARGS__, _)
86 #define CAR_(car, ...) car
88 /* Extracting the tail of an argument list is rather more difficult. The
89 * following trick is based on one by Laurent Deniau to count the number of
90 * arguments to a macro, simplified in two ways: (a) it only handles up to
91 * eight arguments, and (b) it only needs to distinguish the one-argument
92 * case from many arguments. */
93 #define CDR(...) CDR_(__VA_ARGS__, m, m, m, m, m, m, m, 1, _)(__VA_ARGS__)
94 #define CDR_(_1, _2, _3, _4, _5, _6, _7, _8, n, ...) CDR_##n
96 #define CDR_m(_, ...) __VA_ARGS__
102 } consistency_checks
;
114 adns__qf_addr_answer
= 0x01000000,/* addr query received an answer */
115 adns__qf_addr_cname
= 0x02000000 /* addr subquery performed on cname */
118 /* Shared data structures */
130 int dglen
, nsstart
, nscount
, arcount
;
139 struct af_addr
{ int af
; union gen_addr addr
; };
141 #define NREVDOMAINS 2 /* keep in sync with addrfam! */
142 struct revparse_state
{
143 unsigned map
; /* which domains are still live */
144 byte ipv
[NREVDOMAINS
][32]; /* address components so far */
147 union checklabel_state
{
148 struct revparse_state ptr
;
153 void (*callback
)(adns_query parent
, adns_query child
);
157 adns_rrtype rev_rrtype
;
163 } tinfo
; /* type-specific state for the query itself: zero-init if you
164 * don't know better. */
167 adns_rr_hostaddr
*hostaddr
;
168 } pinfo
; /* state for use by parent's callback function */
171 typedef struct typeinfo
{
177 void (*makefinal
)(adns_query qu
, void *data
);
178 /* Change memory management of *data.
179 * Previously, used alloc_interim, now use alloc_final.
182 adns_status (*convstring
)(vbuf
*vb
, const void *data
);
183 /* Converts the RR data to a string representation in vbuf.
184 * vbuf will be appended to (it must have been initialised),
185 * and will not be null-terminated by convstring.
188 adns_status (*parse
)(const parseinfo
*pai
, int cbyte
,
189 int max
, void *store_r
);
190 /* Parse one RR, in dgram of length dglen, starting at cbyte and
191 * extending until at most max.
193 * The RR should be stored at *store_r, of length qu->typei->getrrsz().
195 * If there is an overrun which might indicate truncation, it should set
196 * *rdstart to -1; otherwise it may set it to anything else positive.
198 * nsstart is the offset of the authority section.
201 int (*diff_needswap
)(adns_state ads
,const void *datap_a
,const void *datap_b
);
202 /* Returns !0 if RR a should be strictly after RR b in the sort order,
203 * 0 otherwise. Must not fail.
206 adns_status (*checklabel
)(adns_state ads
, adns_queryflags flags
,
207 union checklabel_state
*cls
, qcontext
*ctx
,
208 int labnum
, const char *label
, int lablen
);
209 /* Check a label from the query domain string. The label is not
210 * necessarily null-terminated. The hook can refuse the query's submission
211 * by returning a nonzero status. State can be stored in *cls between
212 * calls, and useful information can be stashed in ctx->tinfo, to be stored
213 * with the query (e.g., it will be available to the parse hook). This
214 * hook can detect a first call because labnum is zero, and a final call
215 * because lablen is zero.
218 void (*postsort
)(adns_state ads
, void *array
, int nrrs
,int rrsz
,
219 const struct typeinfo
*typei
);
220 /* Called immediately after the RRs have been sorted, and may rearrange
221 * them. (This is really for the benefit of SRV's bizarre weighting
222 * stuff.) May be 0 to mean nothing needs to be done.
225 int (*getrrsz
)(const struct typeinfo
*typei
, adns_rrtype type
);
226 /* Return the output resource-record element size; if this is null, then
227 * the rrsz member can be used.
230 void (*query_send
)(adns_query qu
, struct timeval now
);
231 /* Send the query to nameservers, and hook it into the appropriate queue.
232 * Normal behaviour is to call adns__query_send, but this can be overridden
233 * for special effects.
237 adns_status
adns__ckl_hostname(adns_state ads
, adns_queryflags flags
,
238 union checklabel_state
*cls
,
239 qcontext
*ctx
, int labnum
,
240 const char *label
, int lablen
);
241 /* implemented in query.c, used by types.c as default
242 * and as part of implementation for some fancier types
243 * doesn't require any state */
245 typedef struct allocnode
{
246 struct allocnode
*next
, *back
;
261 enum { query_tosend
, query_tcpw
, query_childw
, query_done
} state
;
262 adns_query back
, next
, parent
;
263 struct { adns_query head
, tail
; } children
;
264 struct { adns_query back
, next
; } siblings
;
265 struct { allocnode
*head
, *tail
; } allocations
;
266 int interim_allocd
, preserved_allocd
;
267 void *final_allocspace
;
269 const typeinfo
*typei
;
274 /* General-purpose messing-about buffer.
275 * Wherever a `big' interface is crossed, this may be corrupted/changed
276 * unless otherwise specified.
280 /* This is allocated when a query is submitted, to avoid being unable
281 * to relate errors to queries if we run out of memory. During
282 * query processing status, rrs is 0. cname is set if
283 * we found a cname (this corresponds to cname_dgram in the query
284 * structure). type is set from the word go. nrrs and rrs
285 * are set together, when we find how many rrs there are.
286 * owner is set during querying unless we're doing searchlist,
287 * in which case it is set only when we find an answer.
291 int cname_dglen
, cname_begin
;
292 /* If non-0, has been allocated using . */
295 int search_origlen
, search_pos
, search_doneabs
;
296 /* Used by the searching algorithm. The query domain in textual form
297 * is copied into the vbuf, and _origlen set to its length. Then
298 * we walk the searchlist, if we want to. _pos says where we are
299 * (next entry to try), and _doneabs says whether we've done the
300 * absolute query yet (0=not yet, 1=done, -1=must do straight away,
301 * but not done yet). If flags doesn't have adns_qf_search then
302 * the vbuf is initialised but empty and everything else is zero.
305 int id
, flags
, retries
;
307 unsigned long udpsent
; /* bitmap indexed by server */
308 struct timeval timeout
;
309 time_t expires
; /* Earliest expiry time of any record we used. */
315 * state Queue child id nextudpserver udpsent tcpfailed
317 * tosend NONE null >=0 0 zero zero
318 * tosend udpw null >=0 any nonzero zero
319 * tosend NONE null >=0 any nonzero zero
321 * tcpw tcpw null >=0 irrelevant any any
323 * child childw set >=0 irrelevant irrelevant irrelevant
324 * child NONE null >=0 irrelevant irrelevant irrelevant
325 * done output null -1 irrelevant irrelevant irrelevant
327 * Queries are only not on a queue when they are actually being processed.
328 * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer)
329 * iff the tcp connection is in state server_ok.
331 * Internal queries (from adns__submit_internal) end up on intdone
332 * instead of output, and the callbacks are made on the way out of
333 * adns, to avoid reentrancy hazards.
335 * +------------------------+
336 * START -----> | tosend/NONE |
337 * +------------------------+
339 * too big for UDP / UDP timeout \ \ send via UDP
340 * send via TCP / more retries \ \
341 * when conn'd / desired \ \
344 * +-----------+ +-------------+
345 * | tcpw/tcpw | ________ | tosend/udpw |
346 * +-----------+ \ +-------------+
347 * | | | UDP timeout | |
350 * \ | TCP died | desired | |
352 * \ \ servers | TCP / |
353 * \ \ to try | timeout / |
355 * reply \ _| +------------------+ / reply
356 * \ | done/output FAIL | /
357 * \ +------------------+ /
360 * (..... got reply ....)
362 * need child query/ies / \ no child query
365 * +---------------+ +----------------+
366 * | childw/childw | ----------------> | done/output OK |
367 * +---------------+ children done +----------------+
371 struct query_queue
{ adns_query head
, tail
; };
376 adns_initflags iflags
;
377 adns_logcallbackfn
*logfn
;
380 struct query_queue udpw
, tcpw
, childw
, output
, intdone
;
381 adns_query forallnext
;
382 int nextid
, tcpsocket
;
383 struct udpsocket
{ int af
; int fd
; } udpsocket
[MAXUDP
];
385 vbuf tcpsend
, tcprecv
;
386 int nservers
, nsortlist
, nsearchlist
, searchndots
, tcpserver
, tcprecv_skip
;
387 enum adns__tcpstate
{
388 server_disconnected
, server_connecting
,
389 server_ok
, server_broken
391 struct timeval tcptimeout
;
392 /* This will have tv_sec==0 if it is not valid. It will always be
393 * valid if tcpstate _connecting. When _ok, it will be nonzero if
394 * we are idle (ie, tcpw queue is empty), in which case it is the
395 * absolute time when we will close the connection.
397 struct sigaction stdsigpipe
;
399 struct pollfd pollfds_buf
[MAX_POLLFDS
];
400 adns_rr_addr servers
[MAXSERVERS
];
403 union gen_addr base
, mask
;
404 } sortlist
[MAXSORTLIST
];
406 unsigned short rand48xsubi
[3];
409 /* From addrfam.c: */
411 extern int adns__af_supported_p(int af
);
412 /* Return nonzero if the address family af known to the library and supported
413 * by the other addrfam operations. Note that the other operations will
414 * abort on an unrecognized address family rather than returning an error
418 extern int adns__genaddr_equal_p(int af
, const union gen_addr
*a
,
419 int bf
, const void *b
);
420 /* b should point to a `struct in_addr' or equivalent for the address family
421 * bf. Returns nonzero if the two addresses are equal.
424 extern int adns__sockaddr_equal_p(const struct sockaddr
*sa
,
425 const struct sockaddr
*sb
);
426 /* Return nonzero if the two socket addresses are equal (in all significant
430 extern int adns__addr_width(int af
);
431 /* Return the width of addresses of family af, in bits. */
433 extern void adns__prefix_mask(int af
, int len
, union gen_addr
*mask_r
);
434 /* Store in mask_r an address mask for address family af, whose first len
435 * bits are set and the remainder are clear. This is what you want for
436 * converting a prefix length into a netmask.
439 extern int adns__guess_prefix_length(int af
, const union gen_addr
*addr
);
440 /* Given a network base address, guess the appropriate prefix length based on
441 * the appropriate rules for the address family (e.g., for IPv4, this uses
442 * the old address classes).
445 extern int adns__addr_match_p(int addraf
, const union gen_addr
*addr
,
446 int netaf
, const union gen_addr
*base
,
447 const union gen_addr
*mask
);
448 /* Given an address af (with family addraf) and a network (with family netaf,
449 * base address base, and netmask mask), return nonzero if the address lies
450 * within the network.
453 extern void adns__sockaddr_extract(const struct sockaddr
*sa
,
454 union gen_addr
*a_r
, int *port_r
);
455 /* Extract fields from the socket address, filling in *a_r and *port_r with
456 * the address and (integer, host byte-order) port number, respectively.
457 * Either (or, pointlessly, both) of a_r and port_r may be null to mean
461 extern void adns__sockaddr_inject(const union gen_addr
*a
, int port
,
462 struct sockaddr
*sa
);
463 /* Inject fields into the socket adress sa. If a is not null, copy the
464 * address in; if port is not -1, then copy the port (converting from host
465 * byte-order). Assumes that sa->sa_family is already set correctly.
468 char *adns__sockaddr_ntoa(const struct sockaddr
*sa
, char *buf
);
469 /* Convert sa to a string, and write it to buf, which must be at least
470 * ADNS_ADDR2TEXT_BUFLEN bytes long (unchecked). Return buf; can't fail.
473 extern int adns__make_reverse_domain(const struct sockaddr
*sa
,
475 char **buf_io
, size_t bufsz
,
477 /* Construct a reverse domain string, given a socket address and a parent
478 * zone. If zone is null, then use the standard reverse-lookup zone for the
479 * address family. If the length of the resulting string is no larger than
480 * bufsz, then the result is stored starting at *buf_io; otherwise a new
481 * buffer is allocated is used, and a pointer to it is stored in both *buf_io
482 * and *buf_free_r (the latter of which should be null on entry). If
483 * something goes wrong, then an errno value is returned: ENOSYS if the
484 * address family of sa isn't recognized, or ENOMEM if the attempt to
485 * allocate an output buffer failed.
488 extern int adns__revparse_label(struct revparse_state
*rps
, int labnum
,
489 const char *label
, int lablen
);
490 /* Parse a label in a reverse-domain name, given its index labnum (starting
491 * from zero), a pointer to its contents (which need not be null-terminated),
492 * and its length. The state in *rps is initialized implicitly when labnum
495 * Returns zero if the parse was successful, nonzero if the domain name is
496 * definitely invalid and the parse must be abandoned.
499 extern int adns__revparse_done(struct revparse_state
*rps
, int nlabels
,
500 adns_rrtype
*rrtype_r
, struct af_addr
*addr_r
);
501 /* Finishes parsing a reverse-domain name, given the total number of labels
502 * in the name. On success, fills in the address in *addr_r, and the forward
503 * query type in *rrtype_r (because that turns out to be useful). Returns
504 * nonzero if the parse must be abandoned.
509 int adns__setnonblock(adns_state ads
, int fd
); /* => errno value */
511 /* From general.c: */
513 void adns__vlprintf(adns_state ads
, const char *fmt
, va_list al
);
514 void adns__lprintf(adns_state ads
, const char *fmt
,
515 ...) PRINTFFORMAT(2,3);
517 void adns__vdiag(adns_state ads
, const char *pfx
, adns_initflags prevent
,
518 int serv
, adns_query qu
, const char *fmt
, va_list al
);
520 void adns__debug(adns_state ads
, int serv
, adns_query qu
,
521 const char *fmt
, ...) PRINTFFORMAT(4,5);
522 void adns__warn(adns_state ads
, int serv
, adns_query qu
,
523 const char *fmt
, ...) PRINTFFORMAT(4,5);
524 void adns__diag(adns_state ads
, int serv
, adns_query qu
,
525 const char *fmt
, ...) PRINTFFORMAT(4,5);
527 int adns__vbuf_ensure(vbuf
*vb
, int want
);
528 int adns__vbuf_appendstr(vbuf
*vb
, const char *data
); /* doesn't include nul */
529 int adns__vbuf_append(vbuf
*vb
, const byte
*data
, int len
);
530 /* 1=>success, 0=>realloc failed */
531 void adns__vbuf_appendq(vbuf
*vb
, const byte
*data
, int len
);
532 void adns__vbuf_init(vbuf
*vb
);
533 void adns__vbuf_free(vbuf
*vb
);
535 const char *adns__diag_domain(adns_state ads
, int serv
, adns_query qu
,
537 const byte
*dgram
, int dglen
, int cbyte
);
538 /* Unpicks a domain in a datagram and returns a string suitable for
539 * printing it as. Never fails - if an error occurs, it will
540 * return some kind of string describing the error.
542 * serv may be -1 and qu may be 0. vb must have been initialised,
543 * and will be left in an arbitrary consistent state.
545 * Returns either vb->buf, or a pointer to a string literal. Do not modify
546 * vb before using the return value.
549 int adns__getrrsz_default(const typeinfo
*typei
, adns_rrtype type
);
550 /* Default function for the `getrrsz' type hook; returns the `fixed_rrsz'
551 * value from the typeinfo entry.
554 void adns__isort(void *array
, int nobjs
, int sz
, void *tempbuf
,
555 int (*needswap
)(void *context
, const void *a
, const void *b
),
557 /* Does an insertion sort of array which must contain nobjs objects
558 * each sz bytes long. tempbuf must point to a buffer at least
559 * sz bytes long. needswap should return !0 if a>b (strictly, ie
560 * wrong order) 0 if a<=b (ie, order is fine).
563 void adns__sigpipe_protect(adns_state
);
564 void adns__sigpipe_unprotect(adns_state
);
565 /* If SIGPIPE protection is not disabled, will block all signals except
566 * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.)
567 * Each call to _protect must be followed by a call to _unprotect before
568 * any significant amount of code gets to run, since the old signal mask
569 * is stored in the adns structure.
572 /* From transmit.c: */
574 adns_status
adns__mkquery(adns_state ads
, vbuf
*vb
, int *id_r
,
575 const char *owner
, int ol
,
576 const typeinfo
*typei
, adns_rrtype type
,
577 adns_queryflags flags
);
578 /* Assembles a query packet in vb. A new id is allocated and returned.
581 adns_status
adns__mkquery_frdgram(adns_state ads
, vbuf
*vb
, int *id_r
,
582 const byte
*qd_dgram
, int qd_dglen
,
584 adns_rrtype type
, adns_queryflags flags
);
585 /* Same as adns__mkquery, but takes the owner domain from an existing datagram.
586 * That domain must be correct and untruncated.
589 void adns__querysend_tcp(adns_query qu
, struct timeval now
);
590 /* Query must be in state tcpw/tcpw; it will be sent if possible and
591 * no further processing can be done on it for now. The connection
592 * might be broken, but no reconnect will be attempted.
595 struct udpsocket
*adns__udpsocket_by_af(adns_state ads
, int af
);
596 /* Find the UDP socket structure in ads which has the given address family.
597 * Return null if there isn't one.
599 * This is used during initialization, so ads is only partially filled in.
600 * The requirements are that nudp is set, and that udpsocket[i].af are
601 * defined for 0<=i<nudp.
604 void adns__query_send(adns_query qu
, struct timeval now
);
605 /* Query must be in state tosend/NONE; it will be moved to a new state,
606 * and no further processing can be done on it for now.
607 * (Resulting state is one of udp/timew, tcpwait/timew (if server not
608 * connected), tcpsent/timew, child/childw or done/output.)
609 * __query_send may decide to use either UDP or TCP depending whether
610 * _qf_usevc is set (or has become set) and whether the query is too
616 adns_status
adns__internal_submit(adns_state ads
, adns_query
*query_r
,
618 const typeinfo
*typei
, adns_rrtype type
,
619 vbuf
*qumsg_vb
, int id
,
620 adns_queryflags flags
, struct timeval now
,
622 /* Submits a query (for internal use, called during external submits).
624 * The new query is returned in *query_r, or we return adns_s_nomemory.
626 * The query datagram should already have been assembled in qumsg_vb;
627 * the memory for it is _taken over_ by this routine whether it
628 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
630 * *ctx is copied byte-for-byte into the query. Before doing this, its tinfo
631 * field may be modified by type hooks.
633 * When the child query is done, ctx->callback will be called. The
634 * child will already have been taken off both the global list of
635 * queries in ads and the list of children in the parent. The child
636 * will be freed when the callback returns. The parent will have been
637 * taken off the global childw queue.
639 * The callback should either call adns__query_done, if it is
640 * complete, or adns__query_fail, if an error has occurred, in which
641 * case the other children (if any) will be cancelled. If the parent
642 * has more unfinished children (or has just submitted more) then the
643 * callback may choose to wait for them - it must then put the parent
644 * back on the childw queue.
647 void adns__search_next(adns_state ads
, adns_query qu
, struct timeval now
);
648 /* Walks down the searchlist for a query with adns_qf_search.
649 * The query should have just had a negative response, or not had
650 * any queries sent yet, and should not be on any queue.
651 * The query_dgram if any will be freed and forgotten and a new
652 * one constructed from the search_* members of the query.
654 * Cannot fail (in case of error, calls adns__query_fail).
657 void *adns__alloc_interim(adns_query qu
, size_t sz
);
658 void *adns__alloc_preserved(adns_query qu
, size_t sz
);
659 /* Allocates some memory, and records which query it came from
660 * and how much there was.
662 * If an error occurs in the query, all the memory from _interim is
663 * simply freed. If the query succeeds, one large buffer will be made
664 * which is big enough for all these allocations, and then
665 * adns__alloc_final will get memory from this buffer.
667 * _alloc_interim can fail (and return 0).
668 * The caller must ensure that the query is failed.
670 * The memory from _preserved is is kept and transferred into the
671 * larger buffer - unless we run out of memory, in which case it too
672 * is freed. When you use _preserved you have to add code to the
673 * x_nomem error exit case in adns__makefinal_query to clear out the
674 * pointers you made to those allocations, because that's when they're
675 * thrown away; you should also make a note in the declaration of
676 * those pointer variables, to note that they are _preserved rather
677 * than _interim. If they're in the answer, note it here:
678 * answer->cname and answer->owner are _preserved.
681 void adns__transfer_interim(adns_query from
, adns_query to
, void *block
);
682 /* Transfers an interim allocation from one query to another, so that
683 * the `to' query will have room for the data when we get to makefinal
684 * and so that the free will happen when the `to' query is freed
685 * rather than the `from' query.
687 * It is legal to call adns__transfer_interim with a null pointer; this
690 * _transfer_interim also ensures that the expiry time of the `to' query
691 * is no later than that of the `from' query, so that child queries'
692 * TTLs get inherited by their parents.
695 void adns__free_interim(adns_query qu
, void *p
);
696 /* Forget about a block allocated by adns__alloc_interim.
699 void *adns__alloc_mine(adns_query qu
, size_t sz
);
700 /* Like _interim, but does not record the length for later
701 * copying into the answer. This just ensures that the memory
702 * will be freed when we're done with the query.
705 void *adns__alloc_final(adns_query qu
, size_t sz
);
706 /* Cannot fail, and cannot return 0.
709 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
);
710 void adns__makefinal_str(adns_query qu
, char **strp
);
712 void adns__reset_preserved(adns_query qu
);
713 /* Resets all of the memory management stuff etc. to take account of
714 * only the _preserved stuff from _alloc_preserved. Used when we find
715 * an error somewhere and want to just report the error (with perhaps
716 * CNAME, owner, etc. info), and also when we're halfway through RRs
717 * in a datagram and discover that we need to retry the query.
720 void adns__cancel(adns_query qu
);
721 void adns__query_done(adns_query qu
);
722 void adns__query_fail(adns_query qu
, adns_status stat
);
723 void adns__cancel_children(adns_query qu
);
725 void adns__returning(adns_state ads
, adns_query qu
);
726 /* Must be called before returning from adns any time that we have
727 * progressed (including made, finished or destroyed) queries.
729 * Might reenter adns via internal query callbacks, so
730 * external-faciing functions which call adns__returning should
731 * normally be avoided in internal code. */
735 void adns__procdgram(adns_state ads
, const byte
*dgram
, int len
,
736 int serv
, int viatcp
, struct timeval now
);
737 /* This function is allowed to cause new datagrams to be constructed
738 * and sent, or even new queries to be started. However,
739 * query-sending functions are not allowed to call any general event
740 * loop functions in case they accidentally call this.
742 * Ie, receiving functions may call sending functions.
743 * Sending functions may NOT call receiving functions.
748 const typeinfo
*adns__findtype(adns_rrtype type
);
757 int dglen
, max
, cbyte
, namelen
;
761 void adns__findlabel_start(findlabel_state
*fls
, adns_state ads
,
762 int serv
, adns_query qu
,
763 const byte
*dgram
, int dglen
, int max
,
764 int dmbegin
, int *dmend_rlater
);
765 /* Finds labels in a domain in a datagram.
767 * Call this routine first.
768 * dmend_rlater may be null. ads (and of course fls) may not be.
769 * serv may be -1, qu may be null - they are for error reporting.
772 adns_status
adns__findlabel_next(findlabel_state
*fls
,
773 int *lablen_r
, int *labstart_r
);
774 /* Then, call this one repeatedly.
776 * It will return adns_s_ok if all is well, and tell you the length
777 * and start of successive labels. labstart_r may be null, but
778 * lablen_r must not be.
780 * After the last label, it will return with *lablen_r zero.
781 * Do not then call it again; instead, just throw away the findlabel_state.
783 * *dmend_rlater will have been set to point to the next part of
784 * the datagram after the label (or after the uncompressed part,
785 * if compression was used). *namelen_rlater will have been set
786 * to the length of the domain name (total length of labels plus
787 * 1 for each intervening dot).
789 * If the datagram appears to be truncated, *lablen_r will be -1.
790 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
791 * Do not call _next again.
793 * There may also be errors, in which case *dmend_rlater,
794 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
795 * Do not then call findlabel_next again.
802 adns_status
adns__parse_domain(adns_state ads
, int serv
, adns_query qu
,
803 vbuf
*vb
, parsedomain_flags flags
,
804 const byte
*dgram
, int dglen
, int *cbyte_io
,
806 /* vb must already have been initialised; it will be reset if necessary.
807 * If there is truncation, vb->used will be set to 0; otherwise
808 * (if there is no error) vb will be null-terminated.
809 * If there is an error vb and *cbyte_io may be left indeterminate.
811 * serv may be -1 and qu may be 0 - they are used for error reporting only.
814 adns_status
adns__parse_domain_more(findlabel_state
*fls
, adns_state ads
,
815 adns_query qu
, vbuf
*vb
,
816 parsedomain_flags flags
,
818 /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state,
819 * for continuing an existing domain or some such of some kind. Also, unlike
820 * _parse_domain, the domain data will be appended to vb, rather than replacing
821 * the existing contents.
824 adns_status
adns__findrr(adns_query qu
, int serv
,
825 const byte
*dgram
, int dglen
, int *cbyte_io
,
826 int *type_r
, int *class_r
, unsigned long *ttl_r
,
827 int *rdlen_r
, int *rdstart_r
,
828 int *ownermatchedquery_r
);
829 /* Finds the extent and some of the contents of an RR in a datagram
830 * and does some checks. The datagram is *dgram, length dglen, and
831 * the RR starts at *cbyte_io (which is updated afterwards to point
832 * to the end of the RR).
834 * The type, class, TTL and RRdata length and start are returned iff
835 * the corresponding pointer variables are not null. type_r, class_r
836 * and ttl_r may not be null. The TTL will be capped.
838 * If ownermatchedquery_r != 0 then the owner domain of this
839 * RR will be compared with that in the query (or, if the query
840 * has gone to a CNAME lookup, with the canonical name).
841 * In this case, *ownermatchedquery_r will be set to 0 or 1.
842 * The query datagram (or CNAME datagram) MUST be valid and not truncated.
844 * If there is truncation then *type_r will be set to -1 and
845 * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
848 * qu must obviously be non-null.
850 * If an error is returned then *type_r will be undefined too.
853 adns_status
adns__findrr_anychk(adns_query qu
, int serv
,
854 const byte
*dgram
, int dglen
, int *cbyte_io
,
855 int *type_r
, int *class_r
,
856 unsigned long *ttl_r
,
857 int *rdlen_r
, int *rdstart_r
,
858 const byte
*eo_dgram
, int eo_dglen
,
859 int eo_cbyte
, int *eo_matched_r
);
860 /* Like adns__findrr_checked, except that the datagram and
861 * owner to compare with can be specified explicitly.
863 * If the caller thinks they know what the owner of the RR ought to
864 * be they can pass in details in eo_*: this is another (or perhaps
865 * the same datagram), and a pointer to where the putative owner
866 * starts in that datagram. In this case *eo_matched_r will be set
867 * to 1 if the datagram matched or 0 if it did not. Either
868 * both eo_dgram and eo_matched_r must both be non-null, or they
869 * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
870 * The eo datagram and contained owner domain MUST be valid and
874 void adns__update_expires(adns_query qu
, unsigned long ttl
,
876 /* Updates the `expires' field in the query, so that it doesn't exceed
880 int vbuf__append_quoted1035(vbuf
*vb
, const byte
*buf
, int len
);
884 void adns__tcp_broken(adns_state ads
, const char *what
, const char *why
);
885 /* what and why may be both 0, or both non-0. */
887 void adns__tcp_tryconnect(adns_state ads
, struct timeval now
);
889 void adns__autosys(adns_state ads
, struct timeval now
);
890 /* Make all the system calls we want to if the application wants us to.
891 * Must not be called from within adns internal processing functions,
892 * lest we end up in recursive descent !
895 void adns__must_gettimeofday(adns_state ads
, const struct timeval
**now_io
,
896 struct timeval
*tv_buf
);
897 /* Call with care - might reentrantly cause queries to be completed! */
899 int adns__pollfds(adns_state ads
, struct pollfd pollfds_buf
[MAX_POLLFDS
]);
900 void adns__fdevents(adns_state ads
,
901 const struct pollfd
*pollfds
, int npollfds
,
902 int maxfd
, const fd_set
*readfds
,
903 const fd_set
*writefds
, const fd_set
*exceptfds
,
904 struct timeval now
, int *r_r
);
905 int adns__internal_check(adns_state ads
,
906 adns_query
*query_io
,
907 adns_answer
**answer
,
910 void adns__timeouts(adns_state ads
, int act
,
911 struct timeval
**tv_io
, struct timeval
*tvbuf
,
913 /* If act is !0, then this will also deal with the TCP connection
914 * if previous events broke it or require it to be connected.
919 void adns__consistency(adns_state ads
, adns_query qu
, consistency_checks cc
);
921 /* Useful static inline functions: */
923 static inline int ctype_whitespace(int c
) {
924 return c
==' ' || c
=='\n' || c
=='\t';
926 static inline int ctype_digit(int c
) { return c
>='0' && c
<='9'; }
927 static inline int ctype_alpha(int c
) {
928 return (c
>= 'a' && c
<= 'z') || (c
>= 'A' && c
<= 'Z');
930 static inline int ctype_822special(int c
) {
931 return strchr("()<>@,;:\\\".[]",c
) != 0;
933 static inline int ctype_domainunquoted(int c
) {
934 return ctype_alpha(c
) || ctype_digit(c
) || (strchr("-_/+",c
) != 0);
937 static inline int errno_resources(int e
) { return e
==ENOMEM
|| e
==ENOBUFS
; }
941 #define MEM_ROUND(sz) \
942 (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
943 * sizeof(union maxalign) )
945 #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff)
946 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
947 #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))
948 #define GET_L(cb,tv) ( (tv)=0, \
949 (tv)|=(GETIL_B((cb))<<24), \
950 (tv)|=(GETIL_B((cb))<<16), \
951 (tv)|=(GETIL_B((cb))<<8), \