dnsdb tlsa lookup
[exim.git] / src / src / exim.h
1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4
5 /* Copyright (c) University of Cambridge 1995 - 2013 */
6 /* See the file NOTICE for conditions of use and distribution. */
7
8
9 /* Source files for exim all #include this header, which drags in everything
10 that is needed. They don't all need everything, of course, but it's far too
11 messy to have each one importing its own list, and anyway, most of them need
12 most of these includes. */
13
14 /* Assume most systems have statfs() unless os.h undefines this macro */
15
16 #define HAVE_STATFS
17
18 /* Similarly, assume most systems have srandom() unless os.h undefines it.
19 This call dates back at least as far as SUSv2. */
20
21 #define HAVE_SRANDOM
22
23 /* This is primarily for the Gnu C library; we define it before os.h so that
24 os.h has a chance to hurriedly undef it, Just In Case. We need C99 for some
25 64-bit math support, and defining _ISOC99_SOURCE breaks <resolv.h> and friends.
26 */
27
28 #define _GNU_SOURCE 1
29
30 /* First of all include the os-specific header, which might set things that
31 are needed by any of the other headers, including system headers. */
32
33 #include "os.h"
34
35 /* If it didn't define os_find_running_interfaces, use the common function. */
36
37 #ifndef os_find_running_interfaces
38 #define os_find_running_interfaces os_common_find_running_interfaces
39 #endif
40
41 /* If it didn't define the base for "base 62" numbers, we really do use 62.
42 This is the case for all real Unix and Unix-like OS. It's only Cygwin and
43 Darwin, with their case-insensitive file systems, that can't use base 62 for
44 making unique names. */
45
46 #ifndef BASE_62
47 #define BASE_62 62
48 #endif
49
50 /* The maximum value of localhost_number depends on the base being used */
51
52 #if BASE_62 == 62
53 #define LOCALHOST_MAX 16
54 #else
55 #define LOCALHOST_MAX 10
56 #endif
57
58 /* If not overridden by os.h, dynamic libraries have filenames ending .so */
59 #ifndef DYNLIB_FN_EXT
60 # define DYNLIB_FN_EXT "so"
61 #endif
62
63 /* ANSI C standard includes */
64
65 #include <ctype.h>
66 #include <locale.h>
67 #include <math.h>
68 #include <signal.h>
69 #include <stdarg.h>
70 #include <stddef.h>
71 #include <stdio.h>
72 #include <stdlib.h>
73 #include <string.h>
74 #include <time.h>
75
76 /* Unix includes */
77
78 #include <errno.h>
79 #if defined(__svr4__) && defined(__sparc) && ! defined(__EXTENSIONS__)
80 #define __EXTENSIONS__ /* so that SunOS 5 gets NGROUPS_MAX */
81 #include <limits.h>
82 #undef __EXTENSIONS__
83 #else
84 #include <limits.h>
85 #endif
86
87 /* C99 integer types, figure out how to undo this if needed for older systems */
88
89 #include <inttypes.h>
90
91 /* Just in case some aged system doesn't define them... */
92
93 #ifndef INT_MAX
94 #define INT_MAX 2147483647
95 #endif
96
97 #ifndef INT_MIN
98 #define INT_MIN (-INT_MAX - 1)
99 #endif
100
101 #ifndef SHRT_MAX
102 #define SHRT_MAX 32767
103 #endif
104
105 #ifndef UCHAR_MAX
106 #define UCHAR_MAX 255
107 #endif
108
109
110 /* To match int_eximarith_t. Define in OS/os.h-<your-system> to override. */
111 #ifndef EXIM_ARITH_MAX
112 # define EXIM_ARITH_MAX ((int_eximarith_t)9223372036854775807LL)
113 #endif
114 #ifndef EXIM_ARITH_MIN
115 # define EXIM_ARITH_MIN (-EXIM_ARITH_MAX - 1)
116 #endif
117
118 /* Some systems have PATH_MAX and some have MAX_PATH_LEN. */
119
120 #ifndef PATH_MAX
121 #ifdef MAX_PATH_LEN
122 #define PATH_MAX MAX_PATH_LEN
123 #else
124 #define PATH_MAX 1024
125 #endif
126 #endif
127
128 #include <sys/types.h>
129 #include <sys/file.h>
130 #include <dirent.h>
131 #include <netdb.h>
132 #ifndef NO_POLL_H
133 #include <poll.h>
134 #endif
135 #include <pwd.h>
136 #include <grp.h>
137 #include <syslog.h>
138
139 /* Not all systems have flock() available. Those that do must define LOCK_SH
140 in sys/file.h. */
141
142 #ifndef LOCK_SH
143 #define NO_FLOCK
144 #endif
145
146 #ifndef NO_SYSEXITS /* some OS don't have this */
147 #include <sysexits.h>
148 #endif
149
150 /* A few OS don't have socklen_t; their os.h files define EXIM_SOCKLEN_T to
151 be size_t or whatever. We used to use SOCKLEN_T, but then it was discovered
152 that this is used by the AIX include files. */
153
154 #ifndef EXIM_SOCKLEN_T
155 #define EXIM_SOCKLEN_T socklen_t
156 #endif
157
158 /* Ensure that the sysexits we reference are defined */
159
160 #ifndef EX_UNAVAILABLE
161 #define EX_UNAVAILABLE 69 /* service unavailable; used for execv fail */
162 #endif
163 #ifndef EX_CANTCREAT
164 #define EX_CANTCREAT 73 /* can't create file: treat as temporary */
165 #endif
166 #ifndef EX_TEMPFAIL
167 #define EX_TEMPFAIL 75 /* temp failure; user is invited to retry */
168 #endif
169 #ifndef EX_CONFIG
170 #define EX_CONFIG 78 /* configuration error */
171 #endif
172
173 /* This one is not in any sysexits file that I've come across */
174
175 #define EX_EXECFAILED 127 /* execve() failed */
176
177
178 #include <sys/time.h>
179 #include <sys/param.h>
180
181 #ifndef NO_SYS_RESOURCE_H /* QNX doesn't have this */
182 #include <sys/resource.h>
183 #endif
184
185 #include <sys/socket.h>
186
187 /* If we are on an IPv6 system, the macro AF_INET6 will have been defined in
188 the sys/socket.h header. It is helpful to have this defined on an IPv4 system
189 so that it can appear in the code, even if it is never actually used when
190 the code is run. It saves some #ifdef occurrences. */
191
192 #ifndef AF_INET6
193 #define AF_INET6 24
194 #endif
195
196 #include <sys/ioctl.h>
197
198 /* The new standard is statvfs; some OS have statfs. For statvfs the block
199 counts must be multiplied by the "fragment size" f_frsize to get the actual
200 size. In other cases the value seems to be f_bsize (which is sometimes the only
201 block size), so we use a macro to get that instead.
202
203 Also arrange to be able to cut it out altogether for way-out OS that don't have
204 anything. I've indented a bit here to try to make the mess a bit more
205 intelligible. Note that simply defining one name to be another when
206 HAVE_SYS_STATVFS_H is not set will not work if the system has a statvfs macro
207 or a macro with entries f_frsize and f_bsize. */
208
209 #ifdef HAVE_STATFS
210 #ifdef HAVE_SYS_STATVFS_H
211 #include <sys/statvfs.h>
212 #define STATVFS statvfs
213 #define F_FRSIZE f_frsize
214 #else
215 #define STATVFS statfs
216 #define F_FRSIZE f_bsize
217 #ifdef HAVE_SYS_VFS_H
218 #include <sys/vfs.h>
219 #ifdef HAVE_SYS_STATFS_H
220 #include <sys/statfs.h>
221 #endif
222 #endif
223 #ifdef HAVE_SYS_MOUNT_H
224 #include <sys/mount.h>
225 #endif
226 #endif
227
228 /* Macros for the fields for the available space for non-superusers; define
229 these only if the OS header has not. Not all OS have f_favail; those that
230 are known to have it define F_FAVAIL as f_favail. The default is to use
231 f_free. */
232
233 #ifndef F_BAVAIL
234 #define F_BAVAIL f_bavail
235 #endif
236
237 #ifndef F_FAVAIL
238 #define F_FAVAIL f_ffree
239 #endif
240
241 /* All the systems I've been able to look at seem to have F_FILES */
242
243 #ifndef F_FILES
244 #define F_FILES f_files
245 #endif
246
247 #endif
248
249
250 #ifndef SIOCGIFCONF /* HACK for SunOS 5 */
251 #include <sys/sockio.h>
252 #endif
253
254 #include <sys/stat.h>
255 #include <sys/wait.h>
256 #include <sys/utsname.h>
257 #include <fcntl.h>
258
259 /* There's a shambles in IRIX6 - it defines EX_OK in unistd.h which conflicts
260 with the definition in sysexits.h. Exim does not actually use this macro, so we
261 just undefine it. It would be nice to be able to re-instate the definition from
262 sysexits.h if there is no definition in unistd.h, but I do not think there is a
263 way to do this in C because macro definitions are not scanned for other macros
264 at definition time. [The code here used to assume they were, until I was
265 disabused of the notion. Luckily, since EX_OK is not used, it didn't matter.] */
266
267 #ifdef EX_OK
268 #undef EX_OK
269 #endif
270
271 #include <unistd.h>
272
273 #include <utime.h>
274 #ifndef NO_NET_IF_H
275 #include <net/if.h>
276 #endif
277 #include <sys/un.h>
278 #include <netinet/in.h>
279 #include <netinet/tcp.h>
280 #include <arpa/inet.h>
281 #include <arpa/nameser.h>
282
283
284 /* If arpa/nameser.h defines a maximum name server packet size, use it,
285 provided it is greater than 2048. Otherwise go for a default. PACKETSZ was used
286 for this, but it seems that NS_PACKETSZ is coming into use. */
287
288 #if defined(NS_PACKETSZ) && NS_PACKETSZ >= 2048
289 #define MAXPACKET NS_PACKETSZ
290 #elif defined(PACKETSZ) && PACKETSZ >= 2048
291 #define MAXPACKET PACKETSZ
292 #else
293 #define MAXPACKET 2048
294 #endif
295
296 /* While IPv6 is still young the definitions of T_AAAA and T_A6 may not be
297 included in arpa/nameser.h. Fudge them here. */
298
299 #ifndef T_AAAA
300 #define T_AAAA 28
301 #endif
302
303 #ifndef T_A6
304 #define T_A6 38
305 #endif
306
307 /* Ancient systems (e.g. SunOS4) don't appear to have T_TXT defined in their
308 header files. I don't suppose they have T_SRV either. */
309
310 #ifndef T_TXT
311 #define T_TXT 16
312 #endif
313
314 #ifndef T_SRV
315 #define T_SRV 33
316 #endif
317
318 /* Many systems do not have T_SPF. */
319
320 #ifndef T_SPF
321 #define T_SPF 99
322 #endif
323
324 /* New TLSA record for DANE */
325 #ifndef T_TLSA
326 #define T_TLSA 52
327 #endif
328 #define MAX_TLSA_EXPANDED_SIZE 8192
329
330 /* It seems that some versions of arpa/nameser.h don't define *any* of the
331 T_xxx macros, which seem to be non-standard nowadays. Just to be on the safe
332 side, put in definitions for all the ones that Exim uses. */
333
334 #ifndef T_A
335 #define T_A 1
336 #endif
337
338 #ifndef T_CNAME
339 #define T_CNAME 5
340 #endif
341
342 #ifndef T_SOA
343 #define T_SOA 6
344 #endif
345
346 #ifndef T_MX
347 #define T_MX 15
348 #endif
349
350 #ifndef T_NS
351 #define T_NS 2
352 #endif
353
354 #ifndef T_PTR
355 #define T_PTR 12
356 #endif
357
358
359 /* We define a few private types for special DNS lookups:
360
361 . T_ZNS gets the nameservers of the enclosing zone of a domain
362
363 . T_MXH gets the MX hostnames only (without their priorities)
364
365 . T_CSA gets the domain's Client SMTP Authorization SRV record
366
367 */
368
369 #define T_ZNS (-1)
370 #define T_MXH (-2)
371 #define T_CSA (-3)
372 #define T_APL (-4)
373
374 /* The resolv.h header defines __P(x) on some Solaris 2.5.1 systems (without
375 checking that it is already defined, in fact). This conflicts with other
376 headers that behave likewise (see below), leading to compiler warnings. Arrange
377 to undefine it if resolv.h defines it. */
378
379 #if defined(__P)
380 #define __P_WAS_DEFINED_BEFORE_RESOLV
381 #endif
382
383 #include <resolv.h>
384
385 #if defined(__P) && ! defined (__P_WAS_DEFINED_BEFORE_RESOLV)
386 #undef __P
387 #endif
388
389 /* If not defined by os.h, we do nothing special to push DNS resolver state
390 back to be available by the classic resolver routines. Also, provide
391 prototype for our get routine, unless defined away. */
392
393 #ifndef os_put_dns_resolver_res
394 # define os_put_dns_resolver_res(R) do {/**/} while(0)
395 #endif
396 #ifndef os_get_dns_resolver_res
397 res_state os_get_dns_resolver_res(void);
398 #endif
399
400 /* These three are to support the IP option logging code. Linux is
401 different to everyone else and there are also other systems which don't
402 have netinet/ip_var.h, so there's a general macro to control its inclusion. */
403
404 #include <netinet/in_systm.h>
405 #include <netinet/ip.h>
406
407 #ifndef NO_IP_VAR_H
408 #include <netinet/ip_var.h>
409 #endif
410
411 /* Linux (and some others) uses a different type for the 2nd argument of
412 iconv(). It's os.h file defines ICONV_ARG2_TYPE. For the rest, define a default
413 here. */
414
415 #ifndef ICONV_ARG2_TYPE
416 #define ICONV_ARG2_TYPE const char **
417 #endif
418
419 /* One OS uses a different type for the 5th argument of getsockopt */
420
421 #ifndef GETSOCKOPT_ARG5_TYPE
422 #define GETSOCKOPT_ARG5_TYPE socklen_t *
423 #endif
424
425 /* One operating system uses a different type for the 2nd argument of select().
426 Its os.h file defines SELECT_ARG2_TYPE. For the rest, define a default here. */
427
428 #ifndef SELECT_ARG2_TYPE
429 #define SELECT_ARG2_TYPE fd_set
430 #endif
431
432 /* One operating system uses a different type for the 4th argument of
433 dn_expand(). Its os.h file defines DN_EXPAND_ARG4_TYPE. For the rest, define a
434 default here. */
435
436 #ifndef DN_EXPAND_ARG4_TYPE
437 #define DN_EXPAND_ARG4_TYPE char *
438 #endif
439
440 /* One operating system defines a different type for the yield of inet_addr().
441 In Exim code, its value is always assigned to the s_addr members of address
442 structures. Casting the yield to the type of s_addr should fix the problem,
443 since the size of the data is correct. Just in case this ever has to be
444 changed, use a macro for the type, and define it here so that it is possible to
445 use different values for specific OS if ever necessary. */
446
447 #ifndef S_ADDR_TYPE
448 #define S_ADDR_TYPE u_long
449 #endif
450
451 /* (At least) one operating system (Solaris) defines a different type for the
452 second argument of pam_converse() - the difference is the absence of "const".
453 Its os.h file defines PAM_CONVERSE_ARG2_TYPE. For the rest, define a default
454 here. */
455
456 #ifndef PAM_CONVERSE_ARG2_TYPE
457 #define PAM_CONVERSE_ARG2_TYPE const struct pam_message
458 #endif
459
460 /* One operating system (SunOS4) defines getc, ungetc, feof, and ferror as
461 macros and not as functions. Exim needs them to be assignable functions. This
462 flag gets set to cause this to be sorted out here. */
463
464 #ifdef FUDGE_GETC_AND_FRIENDS
465 #undef getc
466 extern int getc(FILE *);
467 #undef ungetc
468 extern int ungetc(int, FILE *);
469 #undef feof
470 extern int feof(FILE *);
471 #undef ferror
472 extern int ferror(FILE *);
473 #endif
474
475 /* The header from the PCRE regex package */
476
477 #include <pcre.h>
478
479 /* Exim includes are in several files. Note that local_scan.h #includes
480 config.h, mytypes.h, and store.h, so we don't need to mention them explicitly.
481 */
482
483 #include "local_scan.h"
484 #include "macros.h"
485 #include "dbstuff.h"
486 #include "structs.h"
487 #include "globals.h"
488 #include "functions.h"
489 #include "dbfunctions.h"
490 #include "osfunctions.h"
491
492 #ifdef EXPERIMENTAL_BRIGHTMAIL
493 #include "bmi_spam.h"
494 #endif
495 #ifdef EXPERIMENTAL_SPF
496 #include "spf.h"
497 #endif
498 #ifdef EXPERIMENTAL_SRS
499 #include "srs.h"
500 #endif
501 #ifndef DISABLE_DKIM
502 #include "dkim.h"
503 #endif
504 #ifdef EXPERIMENTAL_DMARC
505 #include "dmarc.h"
506 #include <opendmarc/dmarc.h>
507 #endif
508
509 /* The following stuff must follow the inclusion of config.h because it
510 requires various things that are set therein. */
511
512 #if HAVE_ICONV /* Not all OS have this */
513 #include <iconv.h>
514 #endif
515
516 #if defined(USE_READLINE) || defined(EXPAND_DLFUNC) || defined (LOOKUP_MODULE_DIR)
517 #include <dlfcn.h>
518 #endif
519
520 #ifdef ENABLE_DISABLE_FSYNC
521 #define EXIMfsync(f) (disable_fsync? 0 : fsync(f))
522 #else
523 #define EXIMfsync(f) fsync(f)
524 #endif
525
526 /* Backward compatibility; LOOKUP_LSEARCH now includes all three */
527
528 #if (!defined LOOKUP_LSEARCH) && (defined LOOKUP_WILDLSEARCH || defined LOOKUP_NWILDLSEARCH)
529 #define LOOKUP_LSEARCH yes
530 #endif
531
532 /* Define a union to hold either an IPv4 or an IPv6 sockaddr structure; this
533 simplifies some of the coding. We include the sockaddr to reduce type-punning
534 issues in C99. */
535
536 union sockaddr_46 {
537 struct sockaddr_in v4;
538 #if HAVE_IPV6
539 struct sockaddr_in6 v6;
540 #endif
541 struct sockaddr v0;
542 };
543
544 /* If SUPPORT_TLS is not defined, ensure that USE_GNUTLS is also not defined
545 so that if USE_GNUTLS *is* set, we can assume SUPPORT_TLS is also set. */
546
547 #ifndef SUPPORT_TLS
548 #undef USE_GNUTLS
549 #endif
550
551 /* If SPOOL_DIRECTORY, LOG_FILE_PATH or PID_FILE_PATH have not been defined,
552 set them to the null string. */
553
554 #ifndef SPOOL_DIRECTORY
555 #define SPOOL_DIRECTORY ""
556 #endif
557 #ifndef LOG_FILE_PATH
558 #define LOG_FILE_PATH ""
559 #endif
560 #ifndef PID_FILE_PATH
561 #define PID_FILE_PATH ""
562 #endif
563
564 /* The EDQUOT error code isn't universally available, though it is widespread.
565 There is a particular shambles in SunOS5, where it did not exist originally,
566 but got installed with a particular patch for Solaris 2.4. There is a
567 configuration variable for specifying what the system's "over quota" error is,
568 which will end up in config.h if supplied in OS/Makefile-xxx. If it is not set,
569 default to EDQUOT if it exists, otherwise ENOSPC. */
570
571 #ifndef ERRNO_QUOTA
572 #ifdef EDQUOT
573 #define ERRNO_QUOTA EDQUOT
574 #else
575 #define ERRNO_QUOTA ENOSPC
576 #endif
577 #endif
578
579 /* Ensure PATH_MAX is defined */
580
581 #ifndef PATH_MAX
582 #ifdef MAXPATHLEN
583 #define PATH_MAX MAXPATHLEN
584 #else
585 #define PATH_MAX 1024
586 #endif
587 #endif
588
589 /* End of exim.h */