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
;
134 #define NREVDOMAINS 2 /* keep in sync with addrfam! */
135 struct revparse_state
{
136 unsigned map
; /* which domains are still live */
137 byte ipv
[NREVDOMAINS
][32]; /* address components so far */
140 union checklabel_state
{
141 struct revparse_state ptr
;
146 void (*callback
)(adns_query parent
, adns_query child
);
150 adns_rrtype rev_rrtype
;
156 } tinfo
; /* type-specific state for the query itself: zero-init if you
157 * don't know better. */
160 adns_rr_hostaddr
*hostaddr
;
161 } pinfo
; /* state for use by parent's callback function */
164 typedef struct typeinfo
{
170 void (*makefinal
)(adns_query qu
, void *data
);
171 /* Change memory management of *data.
172 * Previously, used alloc_interim, now use alloc_final.
175 adns_status (*convstring
)(vbuf
*vb
, const void *data
);
176 /* Converts the RR data to a string representation in vbuf.
177 * vbuf will be appended to (it must have been initialised),
178 * and will not be null-terminated by convstring.
181 adns_status (*parse
)(const parseinfo
*pai
, int cbyte
,
182 int max
, void *store_r
);
183 /* Parse one RR, in dgram of length dglen, starting at cbyte and
184 * extending until at most max.
186 * The RR should be stored at *store_r, of length qu->typei->getrrsz().
188 * If there is an overrun which might indicate truncation, it should set
189 * *rdstart to -1; otherwise it may set it to anything else positive.
191 * nsstart is the offset of the authority section.
194 int (*diff_needswap
)(adns_state ads
,const void *datap_a
,const void *datap_b
);
195 /* Returns !0 if RR a should be strictly after RR b in the sort order,
196 * 0 otherwise. Must not fail.
199 adns_status (*checklabel
)(adns_state ads
, adns_queryflags flags
,
200 union checklabel_state
*cls
, qcontext
*ctx
,
201 int labnum
, const char *dgram
,
202 int labstart
, int lablen
);
203 /* Check a label from the query domain string. The label is not
204 * necessarily null-terminated. The hook can refuse the query's submission
205 * by returning a nonzero status. State can be stored in *cls between
206 * calls, and useful information can be stashed in ctx->tinfo, to be stored
207 * with the query (e.g., it will be available to the parse hook). This
208 * hook can detect a first call because labnum is zero, and a final call
209 * because lablen is zero.
212 void (*postsort
)(adns_state ads
, void *array
, int nrrs
,int rrsz
,
213 const struct typeinfo
*typei
);
214 /* Called immediately after the RRs have been sorted, and may rearrange
215 * them. (This is really for the benefit of SRV's bizarre weighting
216 * stuff.) May be 0 to mean nothing needs to be done.
219 int (*getrrsz
)(const struct typeinfo
*typei
, adns_rrtype type
);
220 /* Return the output resource-record element size; if this is null, then
221 * the rrsz member can be used.
224 void (*query_send
)(adns_query qu
, struct timeval now
);
225 /* Send the query to nameservers, and hook it into the appropriate queue.
226 * Normal behaviour is to call adns__query_send, but this can be overridden
227 * for special effects.
231 adns_status
adns__ckl_hostname(adns_state ads
, adns_queryflags flags
,
232 union checklabel_state
*cls
,
233 qcontext
*ctx
, int labnum
,
234 const char *dgram
, int labstart
, int lablen
);
235 /* implemented in query.c, used by types.c as default
236 * and as part of implementation for some fancier types
237 * doesn't require any state */
239 typedef struct allocnode
{
240 struct allocnode
*next
, *back
;
255 enum { query_tosend
, query_tcpw
, query_childw
, query_done
} state
;
256 adns_query back
, next
, parent
;
257 struct { adns_query head
, tail
; } children
;
258 struct { adns_query back
, next
; } siblings
;
259 struct { allocnode
*head
, *tail
; } allocations
;
260 int interim_allocd
, preserved_allocd
;
261 void *final_allocspace
;
263 const typeinfo
*typei
;
268 /* General-purpose messing-about buffer.
269 * Wherever a `big' interface is crossed, this may be corrupted/changed
270 * unless otherwise specified.
274 /* This is allocated when a query is submitted, to avoid being unable
275 * to relate errors to queries if we run out of memory. During
276 * query processing status, rrs is 0. cname is set if
277 * we found a cname (this corresponds to cname_dgram in the query
278 * structure). type is set from the word go. nrrs and rrs
279 * are set together, when we find how many rrs there are.
280 * owner is set during querying unless we're doing searchlist,
281 * in which case it is set only when we find an answer.
285 int cname_dglen
, cname_begin
;
286 /* If non-0, has been allocated using . */
289 int search_origlen
, search_pos
, search_doneabs
;
290 /* Used by the searching algorithm. The query domain in textual form
291 * is copied into the vbuf, and _origlen set to its length. Then
292 * we walk the searchlist, if we want to. _pos says where we are
293 * (next entry to try), and _doneabs says whether we've done the
294 * absolute query yet (0=not yet, 1=done, -1=must do straight away,
295 * but not done yet). If flags doesn't have adns_qf_search then
296 * the vbuf is initialised but empty and everything else is zero.
299 int id
, flags
, retries
;
301 unsigned long udpsent
; /* bitmap indexed by server */
302 struct timeval timeout
;
303 time_t expires
; /* Earliest expiry time of any record we used. */
309 * state Queue child id nextudpserver udpsent tcpfailed
311 * tosend NONE null >=0 0 zero zero
312 * tosend udpw null >=0 any nonzero zero
313 * tosend NONE null >=0 any nonzero zero
315 * tcpw tcpw null >=0 irrelevant any any
317 * child childw set >=0 irrelevant irrelevant irrelevant
318 * child NONE null >=0 irrelevant irrelevant irrelevant
319 * done output null -1 irrelevant irrelevant irrelevant
321 * Queries are only not on a queue when they are actually being processed.
322 * Queries in state tcpw/tcpw have been sent (or are in the to-send buffer)
323 * iff the tcp connection is in state server_ok.
325 * +------------------------+
326 * START -----> | tosend/NONE |
327 * +------------------------+
329 * too big for UDP / UDP timeout \ \ send via UDP
330 * send via TCP / more retries \ \
331 * when conn'd / desired \ \
334 * +-----------+ +-------------+
335 * | tcpw/tcpw | ________ | tosend/udpw |
336 * +-----------+ \ +-------------+
337 * | | | UDP timeout | |
340 * \ | TCP died | desired | |
342 * \ \ servers | TCP / |
343 * \ \ to try | timeout / |
345 * reply \ _| +------------------+ / reply
346 * \ | done/output FAIL | /
347 * \ +------------------+ /
350 * (..... got reply ....)
352 * need child query/ies / \ no child query
355 * +---------------+ +----------------+
356 * | childw/childw | ----------------> | done/output OK |
357 * +---------------+ children done +----------------+
361 struct query_queue
{ adns_query head
, tail
; };
366 adns_initflags iflags
;
367 adns_logcallbackfn
*logfn
;
370 struct query_queue udpw
, tcpw
, childw
, output
;
371 adns_query forallnext
;
372 int nextid
, tcpsocket
;
373 struct udpsocket
{ int af
; int fd
; } udpsocket
[MAXUDP
];
375 vbuf tcpsend
, tcprecv
;
376 int nservers
, nsortlist
, nsearchlist
, searchndots
, tcpserver
, tcprecv_skip
;
377 enum adns__tcpstate
{
378 server_disconnected
, server_connecting
,
379 server_ok
, server_broken
381 struct timeval tcptimeout
;
382 /* This will have tv_sec==0 if it is not valid. It will always be
383 * valid if tcpstate _connecting. When _ok, it will be nonzero if
384 * we are idle (ie, tcpw queue is empty), in which case it is the
385 * absolute time when we will close the connection.
387 struct sigaction stdsigpipe
;
389 struct pollfd pollfds_buf
[MAX_POLLFDS
];
390 adns_rr_addr servers
[MAXSERVERS
];
392 adns_sockaddr base
, mask
;
393 } sortlist
[MAXSORTLIST
];
395 unsigned short rand48xsubi
[3];
398 /* From addrfam.c: */
400 extern int adns__addrs_equal_raw(const struct sockaddr
*a
,
401 int bf
, const void *b
);
402 /* Returns nonzero a's family is bf and a's protocol address field
403 * refers to the same protocol address as that stored at ba.
406 extern int adns__addrs_equal(const adns_sockaddr
*a
,
407 const adns_sockaddr
*b
);
408 /* Returns nonzero if the two refer to the same protocol address
409 * (disregarding port, IPv6 scope, etc).
412 extern int adns__sockaddrs_equal(const struct sockaddr
*sa
,
413 const struct sockaddr
*sb
);
414 /* Return nonzero if the two socket addresses are equal (in all significant
418 extern int adns__addr_width(int af
);
419 /* Return the width of addresses of family af, in bits. */
421 extern void adns__prefix_mask(adns_sockaddr
*sa
, int len
);
422 /* Stores in sa's protocol address field an address mask for address
423 * family af, whose first len bits are set and the remainder are
424 * clear. On entry, sa's af field must be set. This is what you want
425 * for converting a prefix length into a netmask.
428 extern int adns__guess_prefix_length(const adns_sockaddr
*addr
);
429 /* Given a network base address, guess the appropriate prefix length based on
430 * the appropriate rules for the address family (e.g., for IPv4, this uses
431 * the old address classes).
434 extern int adns__addr_matches(int af
, const void *addr
,
435 const adns_sockaddr
*base
,
436 const adns_sockaddr
*mask
);
437 /* Return nonzero if the protocol address specified by af and addr
438 * lies within the network specified by base and mask.
441 extern void adns__addr_inject(const void *a
, adns_sockaddr
*sa
);
442 /* Injects the protocol address *a into the socket adress sa. Assumes
443 * that sa->sa_family is already set correctly.
446 extern const void *adns__sockaddr_addr(const struct sockaddr
*sa
);
447 /* Returns the address of the protocol address field in sa.
450 char *adns__sockaddr_ntoa(const struct sockaddr
*sa
, char *buf
);
451 /* Convert sa to a string, and write it to buf, which must be at least
452 * ADNS_ADDR2TEXT_BUFLEN bytes long (unchecked). Return buf; can't fail.
455 extern int adns__make_reverse_domain(const struct sockaddr
*sa
,
457 char **buf_io
, size_t bufsz
,
459 /* Construct a reverse domain string, given a socket address and a parent
460 * zone. If zone is null, then use the standard reverse-lookup zone for the
461 * address family. If the length of the resulting string is no larger than
462 * bufsz, then the result is stored starting at *buf_io; otherwise a new
463 * buffer is allocated is used, and a pointer to it is stored in both *buf_io
464 * and *buf_free_r (the latter of which should be null on entry). If
465 * something goes wrong, then an errno value is returned: ENOSYS if the
466 * address family of sa isn't recognized, or ENOMEM if the attempt to
467 * allocate an output buffer failed.
470 extern int adns__revparse_label(struct revparse_state
*rps
, int labnum
,
472 int labstart
, int lablen
);
473 /* Parse a label in a reverse-domain name, given its index labnum (starting
474 * from zero), a pointer to its contents (which need not be null-terminated),
475 * and its length. The state in *rps is initialized implicitly when labnum
478 * Returns zero if the parse was successful, nonzero if the domain name is
479 * definitely invalid and the parse must be abandoned.
482 extern int adns__revparse_done(struct revparse_state
*rps
,
483 const char *dgram
, int nlabels
,
484 adns_rrtype
*rrtype_r
, adns_sockaddr
*addr_r
);
485 /* Finishes parsing a reverse-domain name, given the total number of
486 * labels in the name. On success, fills in the af and protocol
487 * address in *addr_r, and the forward query type in *rrtype_r
488 * (because that turns out to be useful). Returns nonzero if the
489 * parse must be abandoned.
494 int adns__setnonblock(adns_state ads
, int fd
); /* => errno value */
496 /* From general.c: */
498 void adns__vlprintf(adns_state ads
, const char *fmt
, va_list al
);
499 void adns__lprintf(adns_state ads
, const char *fmt
,
500 ...) PRINTFFORMAT(2,3);
502 void adns__vdiag(adns_state ads
, const char *pfx
, adns_initflags prevent
,
503 int serv
, adns_query qu
, const char *fmt
, va_list al
);
505 void adns__debug(adns_state ads
, int serv
, adns_query qu
,
506 const char *fmt
, ...) PRINTFFORMAT(4,5);
507 void adns__warn(adns_state ads
, int serv
, adns_query qu
,
508 const char *fmt
, ...) PRINTFFORMAT(4,5);
509 void adns__diag(adns_state ads
, int serv
, adns_query qu
,
510 const char *fmt
, ...) PRINTFFORMAT(4,5);
512 int adns__vbuf_ensure(vbuf
*vb
, int want
);
513 int adns__vbuf_appendstr(vbuf
*vb
, const char *data
); /* doesn't include nul */
514 int adns__vbuf_append(vbuf
*vb
, const byte
*data
, int len
);
515 /* 1=>success, 0=>realloc failed */
516 void adns__vbuf_appendq(vbuf
*vb
, const byte
*data
, int len
);
517 void adns__vbuf_init(vbuf
*vb
);
518 void adns__vbuf_free(vbuf
*vb
);
520 const char *adns__diag_domain(adns_state ads
, int serv
, adns_query qu
,
522 const byte
*dgram
, int dglen
, int cbyte
);
523 /* Unpicks a domain in a datagram and returns a string suitable for
524 * printing it as. Never fails - if an error occurs, it will
525 * return some kind of string describing the error.
527 * serv may be -1 and qu may be 0. vb must have been initialised,
528 * and will be left in an arbitrary consistent state.
530 * Returns either vb->buf, or a pointer to a string literal. Do not modify
531 * vb before using the return value.
534 int adns__getrrsz_default(const typeinfo
*typei
, adns_rrtype type
);
535 /* Default function for the `getrrsz' type hook; returns the `fixed_rrsz'
536 * value from the typeinfo entry.
539 void adns__isort(void *array
, int nobjs
, int sz
, void *tempbuf
,
540 int (*needswap
)(void *context
, const void *a
, const void *b
),
542 /* Does an insertion sort of array which must contain nobjs objects
543 * each sz bytes long. tempbuf must point to a buffer at least
544 * sz bytes long. needswap should return !0 if a>b (strictly, ie
545 * wrong order) 0 if a<=b (ie, order is fine).
548 void adns__sigpipe_protect(adns_state
);
549 void adns__sigpipe_unprotect(adns_state
);
550 /* If SIGPIPE protection is not disabled, will block all signals except
551 * SIGPIPE, and set SIGPIPE's disposition to SIG_IGN. (And then restore.)
552 * Each call to _protect must be followed by a call to _unprotect before
553 * any significant amount of code gets to run, since the old signal mask
554 * is stored in the adns structure.
557 /* From transmit.c: */
559 adns_status
adns__mkquery(adns_state ads
, vbuf
*vb
, int *id_r
,
560 const char *owner
, int ol
,
561 const typeinfo
*typei
, adns_rrtype type
,
562 adns_queryflags flags
);
563 /* Assembles a query packet in vb. A new id is allocated and returned.
566 adns_status
adns__mkquery_frdgram(adns_state ads
, vbuf
*vb
, int *id_r
,
567 const byte
*qd_dgram
, int qd_dglen
,
569 adns_rrtype type
, adns_queryflags flags
);
570 /* Same as adns__mkquery, but takes the owner domain from an existing datagram.
571 * That domain must be correct and untruncated.
574 void adns__querysend_tcp(adns_query qu
, struct timeval now
);
575 /* Query must be in state tcpw/tcpw; it will be sent if possible and
576 * no further processing can be done on it for now. The connection
577 * might be broken, but no reconnect will be attempted.
580 struct udpsocket
*adns__udpsocket_by_af(adns_state ads
, int af
);
581 /* Find the UDP socket structure in ads which has the given address family.
582 * Return null if there isn't one.
584 * This is used during initialization, so ads is only partially filled in.
585 * The requirements are that nudp is set, and that udpsocket[i].af are
586 * defined for 0<=i<nudp.
589 void adns__query_send(adns_query qu
, struct timeval now
);
590 /* Query must be in state tosend/NONE; it will be moved to a new state,
591 * and no further processing can be done on it for now.
592 * (Resulting state is one of udp/timew, tcpwait/timew (if server not
593 * connected), tcpsent/timew, child/childw or done/output.)
594 * __query_send may decide to use either UDP or TCP depending whether
595 * _qf_usevc is set (or has become set) and whether the query is too
601 adns_status
adns__internal_submit(adns_state ads
, adns_query
*query_r
,
602 const typeinfo
*typei
, adns_rrtype type
,
603 vbuf
*qumsg_vb
, int id
,
604 adns_queryflags flags
, struct timeval now
,
606 /* Submits a query (for internal use, called during external submits).
608 * The new query is returned in *query_r, or we return adns_s_nomemory.
610 * The query datagram should already have been assembled in qumsg_vb;
611 * the memory for it is _taken over_ by this routine whether it
612 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
614 * *ctx is copied byte-for-byte into the query. Before doing this, its tinfo
615 * field may be modified by type hooks.
617 * When the child query is done, ctx->callback will be called. The
618 * child will already have been taken off both the global list of
619 * queries in ads and the list of children in the parent. The child
620 * will be freed when the callback returns. The parent will have been
621 * taken off the global childw queue.
623 * The callback should either call adns__query_done, if it is
624 * complete, or adns__query_fail, if an error has occurred, in which
625 * case the other children (if any) will be cancelled. If the parent
626 * has more unfinished children (or has just submitted more) then the
627 * callback may choose to wait for them - it must then put the parent
628 * back on the childw queue.
631 void adns__search_next(adns_state ads
, adns_query qu
, struct timeval now
);
632 /* Walks down the searchlist for a query with adns_qf_search.
633 * The query should have just had a negative response, or not had
634 * any queries sent yet, and should not be on any queue.
635 * The query_dgram if any will be freed and forgotten and a new
636 * one constructed from the search_* members of the query.
638 * Cannot fail (in case of error, calls adns__query_fail).
641 void *adns__alloc_interim(adns_query qu
, size_t sz
);
642 void *adns__alloc_preserved(adns_query qu
, size_t sz
);
643 /* Allocates some memory, and records which query it came from
644 * and how much there was.
646 * If an error occurs in the query, all the memory from _interim is
647 * simply freed. If the query succeeds, one large buffer will be made
648 * which is big enough for all these allocations, and then
649 * adns__alloc_final will get memory from this buffer.
651 * _alloc_interim can fail (and return 0).
652 * The caller must ensure that the query is failed.
654 * The memory from _preserved is is kept and transferred into the
655 * larger buffer - unless we run out of memory, in which case it too
656 * is freed. When you use _preserved you have to add code to the
657 * x_nomem error exit case in adns__makefinal_query to clear out the
658 * pointers you made to those allocations, because that's when they're
659 * thrown away; you should also make a note in the declaration of
660 * those pointer variables, to note that they are _preserved rather
661 * than _interim. If they're in the answer, note it here:
662 * answer->cname and answer->owner are _preserved.
665 void adns__transfer_interim(adns_query from
, adns_query to
, void *block
);
666 /* Transfers an interim allocation from one query to another, so that
667 * the `to' query will have room for the data when we get to makefinal
668 * and so that the free will happen when the `to' query is freed
669 * rather than the `from' query.
671 * It is legal to call adns__transfer_interim with a null pointer; this
674 * _transfer_interim also ensures that the expiry time of the `to' query
675 * is no later than that of the `from' query, so that child queries'
676 * TTLs get inherited by their parents.
679 void adns__free_interim(adns_query qu
, void *p
);
680 /* Forget about a block allocated by adns__alloc_interim.
683 void *adns__alloc_mine(adns_query qu
, size_t sz
);
684 /* Like _interim, but does not record the length for later
685 * copying into the answer. This just ensures that the memory
686 * will be freed when we're done with the query.
689 void *adns__alloc_final(adns_query qu
, size_t sz
);
690 /* Cannot fail, and cannot return 0.
693 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
);
694 void adns__makefinal_str(adns_query qu
, char **strp
);
696 void adns__reset_preserved(adns_query qu
);
697 /* Resets all of the memory management stuff etc. to take account of
698 * only the _preserved stuff from _alloc_preserved. Used when we find
699 * an error somewhere and want to just report the error (with perhaps
700 * CNAME, owner, etc. info), and also when we're halfway through RRs
701 * in a datagram and discover that we need to retry the query.
704 void adns__query_done(adns_query qu
);
705 void adns__query_fail(adns_query qu
, adns_status stat
);
706 void adns__cancel_children(adns_query qu
);
710 void adns__procdgram(adns_state ads
, const byte
*dgram
, int len
,
711 int serv
, int viatcp
, struct timeval now
);
712 /* This function is allowed to cause new datagrams to be constructed
713 * and sent, or even new queries to be started. However,
714 * query-sending functions are not allowed to call any general event
715 * loop functions in case they accidentally call this.
717 * Ie, receiving functions may call sending functions.
718 * Sending functions may NOT call receiving functions.
723 const typeinfo
*adns__findtype(adns_rrtype type
);
732 int dglen
, max
, cbyte
, namelen
;
736 void adns__findlabel_start(findlabel_state
*fls
, adns_state ads
,
737 int serv
, adns_query qu
,
738 const byte
*dgram
, int dglen
, int max
,
739 int dmbegin
, int *dmend_rlater
);
740 /* Finds labels in a domain in a datagram.
742 * Call this routine first.
743 * dmend_rlater may be null. ads (and of course fls) may not be.
744 * serv may be -1, qu may be null - they are for error reporting.
747 adns_status
adns__findlabel_next(findlabel_state
*fls
,
748 int *lablen_r
, int *labstart_r
);
749 /* Then, call this one repeatedly.
751 * It will return adns_s_ok if all is well, and tell you the length
752 * and start of successive labels. labstart_r may be null, but
753 * lablen_r must not be.
755 * After the last label, it will return with *lablen_r zero.
756 * Do not then call it again; instead, just throw away the findlabel_state.
758 * *dmend_rlater will have been set to point to the next part of
759 * the datagram after the label (or after the uncompressed part,
760 * if compression was used). *namelen_rlater will have been set
761 * to the length of the domain name (total length of labels plus
762 * 1 for each intervening dot).
764 * If the datagram appears to be truncated, *lablen_r will be -1.
765 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
766 * Do not call _next again.
768 * There may also be errors, in which case *dmend_rlater,
769 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
770 * Do not then call findlabel_next again.
777 adns_status
adns__parse_domain(adns_state ads
, int serv
, adns_query qu
,
778 vbuf
*vb
, parsedomain_flags flags
,
779 const byte
*dgram
, int dglen
, int *cbyte_io
,
781 /* vb must already have been initialised; it will be reset if necessary.
782 * If there is truncation, vb->used will be set to 0; otherwise
783 * (if there is no error) vb will be null-terminated.
784 * If there is an error vb and *cbyte_io may be left indeterminate.
786 * serv may be -1 and qu may be 0 - they are used for error reporting only.
789 adns_status
adns__parse_domain_more(findlabel_state
*fls
, adns_state ads
,
790 adns_query qu
, vbuf
*vb
,
791 parsedomain_flags flags
,
793 /* Like adns__parse_domain, but you pass it a pre-initialised findlabel_state,
794 * for continuing an existing domain or some such of some kind. Also, unlike
795 * _parse_domain, the domain data will be appended to vb, rather than replacing
796 * the existing contents.
799 adns_status
adns__findrr(adns_query qu
, int serv
,
800 const byte
*dgram
, int dglen
, int *cbyte_io
,
801 int *type_r
, int *class_r
, unsigned long *ttl_r
,
802 int *rdlen_r
, int *rdstart_r
,
803 int *ownermatchedquery_r
);
804 /* Finds the extent and some of the contents of an RR in a datagram
805 * and does some checks. The datagram is *dgram, length dglen, and
806 * the RR starts at *cbyte_io (which is updated afterwards to point
807 * to the end of the RR).
809 * The type, class, TTL and RRdata length and start are returned iff
810 * the corresponding pointer variables are not null. type_r, class_r
811 * and ttl_r may not be null. The TTL will be capped.
813 * If ownermatchedquery_r != 0 then the owner domain of this
814 * RR will be compared with that in the query (or, if the query
815 * has gone to a CNAME lookup, with the canonical name).
816 * In this case, *ownermatchedquery_r will be set to 0 or 1.
817 * The query datagram (or CNAME datagram) MUST be valid and not truncated.
819 * If there is truncation then *type_r will be set to -1 and
820 * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
823 * qu must obviously be non-null.
825 * If an error is returned then *type_r will be undefined too.
828 adns_status
adns__findrr_anychk(adns_query qu
, int serv
,
829 const byte
*dgram
, int dglen
, int *cbyte_io
,
830 int *type_r
, int *class_r
,
831 unsigned long *ttl_r
,
832 int *rdlen_r
, int *rdstart_r
,
833 const byte
*eo_dgram
, int eo_dglen
,
834 int eo_cbyte
, int *eo_matched_r
);
835 /* Like adns__findrr_checked, except that the datagram and
836 * owner to compare with can be specified explicitly.
838 * If the caller thinks they know what the owner of the RR ought to
839 * be they can pass in details in eo_*: this is another (or perhaps
840 * the same datagram), and a pointer to where the putative owner
841 * starts in that datagram. In this case *eo_matched_r will be set
842 * to 1 if the datagram matched or 0 if it did not. Either
843 * both eo_dgram and eo_matched_r must both be non-null, or they
844 * must both be null (in which case eo_dglen and eo_cbyte will be ignored).
845 * The eo datagram and contained owner domain MUST be valid and
849 void adns__update_expires(adns_query qu
, unsigned long ttl
,
851 /* Updates the `expires' field in the query, so that it doesn't exceed
855 int vbuf__append_quoted1035(vbuf
*vb
, const byte
*buf
, int len
);
857 bool adns__labels_equal(const byte
*a
, int al
, const byte
*b
, int bl
);
861 void adns__tcp_broken(adns_state ads
, const char *what
, const char *why
);
862 /* what and why may be both 0, or both non-0. */
864 void adns__tcp_tryconnect(adns_state ads
, struct timeval now
);
866 void adns__autosys(adns_state ads
, struct timeval now
);
867 /* Make all the system calls we want to if the application wants us to.
868 * Must not be called from within adns internal processing functions,
869 * lest we end up in recursive descent !
872 void adns__must_gettimeofday(adns_state ads
, const struct timeval
**now_io
,
873 struct timeval
*tv_buf
);
875 int adns__pollfds(adns_state ads
, struct pollfd pollfds_buf
[MAX_POLLFDS
]);
876 void adns__fdevents(adns_state ads
,
877 const struct pollfd
*pollfds
, int npollfds
,
878 int maxfd
, const fd_set
*readfds
,
879 const fd_set
*writefds
, const fd_set
*exceptfds
,
880 struct timeval now
, int *r_r
);
881 int adns__internal_check(adns_state ads
,
882 adns_query
*query_io
,
883 adns_answer
**answer
,
886 void adns__timeouts(adns_state ads
, int act
,
887 struct timeval
**tv_io
, struct timeval
*tvbuf
,
889 /* If act is !0, then this will also deal with the TCP connection
890 * if previous events broke it or require it to be connected.
895 void adns__consistency(adns_state ads
, adns_query qu
, consistency_checks cc
);
897 /* Useful static inline functions: */
899 static inline int ctype_whitespace(int c
) {
900 return c
==' ' || c
=='\n' || c
=='\t';
902 static inline int ctype_digit(int c
) { return c
>='0' && c
<='9'; }
903 static inline int ctype_alpha(int c
) {
904 return (c
>= 'a' && c
<= 'z') || (c
>= 'A' && c
<= 'Z');
906 static inline int ctype_toupper(int c
) {
907 return ctype_alpha(c
) ?
(c
& ~32) : c
;
909 static inline int ctype_822special(int c
) {
910 return strchr("()<>@,;:\\\".[]",c
) != 0;
912 static inline int ctype_domainunquoted(int c
) {
913 return ctype_alpha(c
) || ctype_digit(c
) || (strchr("-_/+",c
) != 0);
916 static inline int errno_resources(int e
) { return e
==ENOMEM
|| e
==ENOBUFS
; }
920 #define MEM_ROUND(sz) \
921 (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
922 * sizeof(union maxalign) )
924 #define GETIL_B(cb) (((dgram)[(cb)++]) & 0x0ff)
925 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
926 #define GET_W(cb,tv) ((tv)=0,(tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))
927 #define GET_L(cb,tv) ( (tv)=0, \
928 (tv)|=(GETIL_B((cb))<<24), \
929 (tv)|=(GETIL_B((cb))<<16), \
930 (tv)|=(GETIL_B((cb))<<8), \