257953fd1185d66f57e84ba2b45124ed912d401b
3 * - declarations of private objects with external linkage (adns__*)
4 * - definitons of internal macros
5 * - comments regarding library data structures
8 * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2, or (at your option)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software Foundation,
22 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 #ifndef ADNS_INTERNAL_H_INCLUDED
26 #define ADNS_INTERNAL_H_INCLUDED
28 #define PRINTFFORMAT(a,b) __attribute__((format(printf,a,b)))
29 typedef unsigned char byte
;
39 /* Configuration and constants */
42 #define UDPMAXRETRIES /*15*/5
43 #define UDPRETRYMS 2000
45 #define LOCALRESOURCEMS 20
48 #define DNS_MAXUDP 512
49 #define DNS_MAXDOMAIN 255
50 #define DNS_HDRSIZE 12
51 #define DNS_CLASS_IN 1
62 /* Shared data structures */
88 adns_status (*parse
)(adns_query qu
, int serv
,
89 const byte
*dgram
, int dglen
, int cbyte
, int max
,
91 /* Parse one RR, in dgram of length dglen, starting at cbyte and
92 * extending until at most max.
94 * The RR should be stored at *store_r, of length qu->typei->rrsz.
96 * If there is an overrun which might indicate truncation, it should set
97 * *rdstart to -1; otherwise it may set it to anything else positive.
100 void (*makefinal
)(adns_query qu
, void *data
);
101 /* Change memory management of *data.
102 * Previously, used alloc_interim, now use alloc_final.
106 typedef struct allocnode
{
107 struct allocnode
*next
;
121 enum { query_udp
, query_tcpwait
, query_tcpsent
, query_child
, query_done
} state
;
122 adns_query back
, next
, parent
;
123 struct { adns_query head
, tail
; } children
;
124 struct { adns_query back
, next
; } siblings
;
125 struct allocnode
*allocations
;
127 void *final_allocspace
;
129 const typeinfo
*typei
;
134 /* General-purpose messing-about buffer.
135 * Wherever a `big' interface is crossed, this may be corrupted/changed
136 * unless otherwise specified.
140 /* This is allocated when a query is submitted, to avoid being unable
141 * to relate errors to queries if we run out of memory. During
142 * query processing status, rrs is 0. cname is set if
143 * we found a cname (this corresponds to cname_dgram in the query
144 * structure). type is set from the word go. nrrs and rrs
145 * are set together, when we find how many rrs there are.
149 int cname_dglen
, cname_begin
;
150 /* If non-0, has been allocated using . */
152 int id
, flags
, udpretries
;
154 unsigned long udpsent
, tcpfailed
; /* bitmap indexed by server */
155 struct timeval timeout
;
160 * state Queue child id nextudpserver sentudp failedtcp
162 * udp NONE null >=0 0 zero zero
163 * udp timew null >=0 any nonzero zero
164 * udp NONE null >=0 any nonzero zero
166 * tcpwait timew null >=0 irrelevant zero any
167 * tcpsent timew null >=0 irrelevant zero any
169 * child childw set >=0 irrelevant irrelevant irrelevant
170 * done output null -1 irrelevant irrelevant irrelevant
172 * +------------------------+
173 * START -----> | udp/NONE |
174 * +------------------------+
176 * too big for UDP / UDP timeout \ \ send via UDP
177 * do this ASAP! / more retries \ \ do this ASAP!
179 * +---------------+ +-----------+
180 * | tcpwait/timew | ____ | udp/timew |
181 * +---------------+ \ +-----------+
183 * TCP conn'd; | | TCP died | | |
184 * send via TCP | | more | UDP timeout | |
185 * do this ASAP! | | servers | no more | |
186 * v | to try | retries | |
187 * +---------------+ | desired | |
188 * | tcpsent/timew | ____ | | |
189 * +---------------+ \| | |
190 * \ \ TCP died | TCP | |
191 * \ \ no more | timeout / |
195 * reply \ _| +------------------+ / reply
196 * \ | done/output FAIL | /
197 * \ +------------------+ /
200 * (..... got reply ....)
202 * need child query/ies / \ no child query
205 * +--------------+ +----------------+
206 * | child/childw | ----------------> | done/output OK |
207 * +--------------+ children done +----------------+
212 adns_initflags iflags
;
214 struct { adns_query head
, tail
; } timew
, childw
, output
;
215 int nextid
, udpsocket
, tcpsocket
;
216 vbuf tcpsend
, tcprecv
;
217 int nservers
, tcpserver
;
218 enum adns__tcpstate
{ server_disconnected
, server_connecting
, server_ok
} tcpstate
;
219 struct timeval tcptimeout
;
222 } servers
[MAXSERVERS
];
227 int adns__setnonblock(adns_state ads
, int fd
); /* => errno value */
229 /* From general.c: */
231 void adns__vdiag(adns_state ads
, const char *pfx
, adns_initflags prevent
,
232 int serv
, adns_query qu
, const char *fmt
, va_list al
);
234 void adns__debug(adns_state ads
, int serv
, adns_query qu
,
235 const char *fmt
, ...) PRINTFFORMAT(4,5);
236 void adns__warn(adns_state ads
, int serv
, adns_query qu
,
237 const char *fmt
, ...) PRINTFFORMAT(4,5);
238 void adns__diag(adns_state ads
, int serv
, adns_query qu
,
239 const char *fmt
, ...) PRINTFFORMAT(4,5);
241 int adns__vbuf_ensure(vbuf
*vb
, int want
);
242 int adns__vbuf_appendstr(vbuf
*vb
, const char *data
); /* does not include nul */
243 int adns__vbuf_append(vbuf
*vb
, const byte
*data
, int len
);
244 /* 1=>success, 0=>realloc failed */
245 void adns__vbuf_appendq(vbuf
*vb
, const byte
*data
, int len
);
246 void adns__vbuf_init(vbuf
*vb
);
247 void adns__vbuf_free(vbuf
*vb
);
249 const char *adns__diag_domain(adns_state ads
, int serv
, adns_query qu
, vbuf
*vb
,
250 int flags
, const byte
*dgram
, int dglen
, int cbyte
);
251 /* Unpicks a domain in a datagram and returns a string suitable for
252 * printing it as. Never fails - if an error occurs, it will
253 * return some kind of string describing the error.
255 * serv may be -1 and qu may be 0. vb must have been initialised,
256 * and will be left in an arbitrary consistent state.
258 * Returns either vb->buf, or a pointer to a string literal. Do not modify
259 * vb before using the return value.
262 /* From transmit.c: */
264 adns_status
adns__mkquery(adns_state ads
, vbuf
*vb
, int *id_r
,
265 const char *owner
, int ol
,
266 const typeinfo
*typei
, adns_queryflags flags
);
267 /* Assembles a query packet in vb, and returns id at *id_r. */
269 void adns__query_tcp(adns_query qu
, struct timeval now
);
270 /* Query must be in state tcpwait/timew; it will be moved to a new state
271 * if possible and no further processing can be done on it for now.
272 * (Resulting state is one of tcpwait/timew (if server not connected),
273 * tcpsent/timew, child/childw or done/output.)
275 * adns__tcp_tryconnect should already have been called - _tcp
276 * will only use an existing connection (if there is one), which it
277 * may break. If the conn list lost then the caller is responsible for any
278 * reestablishment and retry.
281 void adns__query_udp(adns_query qu
, struct timeval now
);
282 /* Query must be in state udp/NONE; it will be moved to a new state,
283 * and no further processing can be done on it for now.
284 * (Resulting state is one of udp/timew, tcpwait/timew (if server not connected),
285 * tcpsent/timew, child/childw or done/output.)
290 int adns__internal_submit(adns_state ads
, adns_query
*query_r
,
291 const typeinfo
*typei
, vbuf
*qumsg_vb
, int id
,
292 adns_queryflags flags
, struct timeval now
,
293 adns_status failstat
, const qcontext
*ctx
);
294 /* Submits a query (for internal use, called during external submits).
296 * The new query is returned in *query_r, or we return adns_s_nomemory.
298 * The query datagram should already have been assembled in qumsg_vb;
299 * the memory for it is _taken over_ by this routine whether it
300 * succeeds or fails (if it succeeds, the vbuf is reused for qu->vb).
302 * If failstat is nonzero then if we are successful in creating the query
303 * it is immediately failed with code failstat (but _submit still succeds).
305 * ctx is copied byte-for-byte into the query.
308 void *adns__alloc_interim(adns_query qu
, size_t sz
);
309 /* Allocates some memory, and records which query it came from
310 * and how much there was.
312 * If an error occurs in the query, all its memory is simply freed.
314 * If the query succeeds, one large buffer will be made which is
315 * big enough for all these allocations, and then adns__alloc_final
316 * will get memory from this buffer.
318 * _alloc_interim can fail, in which case it will fail the query too,
319 * so nothing more need be done with it.
321 * adns__alloc_interim(qu,0) will not return 0, but it will not
322 * necessarily return a distinct pointer each time.
325 void *adns__alloc_mine(adns_query qu
, size_t sz
);
326 /* Like _interim, but does not record the length for later
327 * copying into the answer. This just ensures that the memory
328 * will be freed when we're done with the query.
331 void *adns__alloc_final(adns_query qu
, size_t sz
);
332 /* Cannot fail, and cannot return 0.
335 void adns__makefinal_block(adns_query qu
, void **blpp
, size_t sz
);
336 void adns__makefinal_str(adns_query qu
, char **strp
);
338 void adns__reset_cnameonly(adns_query qu
);
339 /* Resets all of the memory management stuff etc. to
340 * take account of only the CNAME. Used when we find an error somewhere
341 * and want to just report the error (with perhaps CNAME info), and also
342 * when we're halfway through RRs in a datagram and discover that we
343 * need to retry the query.
346 void adns__query_done(adns_query qu
);
347 void adns__query_fail(adns_query qu
, adns_status stat
);
351 void adns__procdgram(adns_state ads
, const byte
*dgram
, int len
,
352 int serv
, struct timeval now
);
356 const typeinfo
*adns__findtype(adns_rrtype type
);
365 int dglen
, max
, cbyte
, namelen
;
369 void adns__findlabel_start(findlabel_state
*fls
, adns_state ads
,
370 int serv
, adns_query qu
,
371 const byte
*dgram
, int dglen
, int max
,
372 int dmbegin
, int *dmend_rlater
);
373 /* Finds labels in a domain in a datagram.
375 * Call this routine first.
376 * dmend_rlater may be null. ads (and of course fls) may not be.
377 * serv may be -1, qu may be null - they are for error reporting.
380 adns_status
adns__findlabel_next(findlabel_state
*fls
, int *lablen_r
, int *labstart_r
);
381 /* Then, call this one repeatedly.
383 * It will return adns_s_ok if all is well, and tell you the length
384 * and start of successive labels. labstart_r may be null, but
385 * lablen_r must not be.
387 * After the last label, it will return with *lablen_r zero.
388 * Do not then call it again; instead, just throw away the findlabel_state.
390 * *dmend_rlater will have been set to point to the next part of
391 * the datagram after the label (or after the uncompressed part,
392 * if compression was used). *namelen_rlater will have been set
393 * to the length of the domain name (total length of labels plus
394 * 1 for each intervening dot).
396 * If the datagram appears to be truncated, *lablen_r will be -1.
397 * *dmend_rlater, *labstart_r and *namelen_r may contain garbage.
398 * Do not call _next again.
400 * There may also be errors, in which case *dmend_rlater,
401 * *namelen_rlater, *lablen_r and *labstart_r may contain garbage.
402 * Do not then call findlabel_next again.
405 adns_status
adns__parse_domain(adns_state ads
, int serv
, adns_query qu
,
407 const byte
*dgram
, int dglen
, int *cbyte_io
, int max
);
408 /* vb must already have been initialised; it will be reset if necessary.
409 * If there is truncation, vb->used will be set to 0; otherwise
410 * (if there is no error) vb will be null-terminated.
411 * If there is an error vb and *cbyte_io may be left indeterminate.
413 * serv may be -1 and qu may be 0 - they are used for error reporting only.
416 adns_status
adns__findrr(adns_query qu
, int serv
,
417 const byte
*dgram
, int dglen
, int *cbyte_io
,
418 int *type_r
, int *class_r
, int *rdlen_r
, int *rdstart_r
,
419 int *ownermatchedquery_r
);
420 /* Finds the extent and some of the contents of an RR in a datagram
421 * and does some checks. The datagram is *dgram, length dglen, and
422 * the RR starts at *cbyte_io (which is updated afterwards to point
423 * to the end of the RR).
425 * The type, class and RRdata length and start are returned iff
426 * the corresponding pointer variables are not null. type_r and
427 * class_r may not be null.
429 * If ownermatchedquery_r != 0 then the owner domain of this
430 * RR will be compared with that in the query (or, if the query
431 * has gone to a CNAME lookup, with the canonical name).
432 * In this case, *ownermatchedquery_r will be set to 0 or 1.
433 * The query datagram (or CNAME datagram) MUST be valid and not truncated.
435 * If there is truncation then *type_r will be set to -1 and
436 * *cbyte_io, *class_r, *rdlen_r, *rdstart_r and *eo_matched_r will be
439 * qu must obviously be non-null.
441 * If an error is returned then *type_r will be undefined too.
444 int vbuf__append_quoted1035(vbuf
*vb
, const byte
*buf
, int len
);
448 void adns__tcp_broken(adns_state ads
, const char *what
, const char *why
);
449 void adns__tcp_tryconnect(adns_state ads
, struct timeval now
);
451 void adns__autosys(adns_state ads
, struct timeval now
);
452 /* Make all the system calls we want to if the application wants us to. */
454 /* Useful static inline functions: */
456 static inline void timevaladd(struct timeval
*tv_io
, long ms
) {
460 tmp
.tv_usec
+= (ms
%1000)*1000000;
461 tmp
.tv_sec
+= ms
/1000;
462 if (tmp
.tv_usec
>= 1000000) { tmp
.tv_sec
++; tmp
.tv_usec
-= 1000; }
466 static inline int ctype_whitespace(int c
) { return c
==' ' || c
=='\n' || c
=='\t'; }
467 static inline int ctype_digit(int c
) { return c
>='0' && c
<='9'; }
468 static inline int ctype_alpha(int c
) {
469 return (c
>= 'a' && c
<= 'z') || (c
>= 'A' || c
<= 'Z');
474 #define MEM_ROUND(sz) \
475 (( ((sz)+sizeof(union maxalign)-1) / sizeof(union maxalign) ) \
476 * sizeof(union maxalign) )
478 #define LIST_INIT(list) ((list).head= (list).tail= 0)
480 #define LIST_UNLINK_PART(list,node,part) \
482 if ((node)->back) (node)->back->part next= (node)->part next; \
483 else (list).head= (node)->part next; \
484 if ((node)->next) (node)->next->part back= (node)->part back; \
485 else (list).tail= (node)->part back; \
488 #define LIST_LINK_TAIL_PART(list,node,part) \
490 (node)->part back= 0; \
491 (node)->part next= (list).tail; \
492 if ((list).tail) (list).tail->part back= (node); else (list).part head= (node); \
493 (list).tail= (node); \
496 #define LIST_UNLINK(list,node) LIST_UNLINK_PART(list,node,)
497 #define LIST_LINK_TAIL(list,node) LIST_LINK_TAIL_PART(list,node,)
499 #define GETIL_B(cb) (dgram[(cb)++])
500 #define GET_B(cb,tv) ((tv)= GETIL_B((cb)))
501 #define GET_W(cb,tv) ((tv)=0, (tv)|=(GETIL_B((cb))<<8), (tv)|=GETIL_B(cb), (tv))