src/exim.h

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   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 #ifndef EXIM_H
  15 #define EXIM_H
  16
  17 /* Assume most systems have statfs() unless os.h undefines this macro */
  18
  19 #define HAVE_STATFS
  20
  21 /* Similarly, assume most systems have srandom() unless os.h undefines it.
  22 This call dates back at least as far as SUSv2. */
  23
  24 #define HAVE_SRANDOM
  25
  26 /* This is primarily for the Gnu C library; we define it before os.h so that
  27 os.h has a chance to hurriedly undef it, Just In Case.  We need C99 for some
  28 64-bit math support, and defining _ISOC99_SOURCE breaks <resolv.h> and friends.
  29 */
  30
  31 #define _GNU_SOURCE 1
  32
  33 /* First of all include the os-specific header, which might set things that
  34 are needed by any of the other headers, including system headers. */
  35
  36 #include "os.h"
  37
  38 /* If it didn't define os_find_running_interfaces, use the common function. */
  39
  40 #ifndef os_find_running_interfaces
  41 # define os_find_running_interfaces os_common_find_running_interfaces
  42 #endif
  43
  44 /* If it didn't define the base for "base 62" numbers, we really do use 62.
  45 This is the case for all real Unix and Unix-like OS. It's only Cygwin and
  46 Darwin, with their case-insensitive file systems, that can't use base 62 for
  47 making unique names. */
  48
  49 #ifndef BASE_62
  50 # define BASE_62 62
  51 #endif
  52
  53 /* The maximum value of localhost_number depends on the base being used */
  54
  55 #if BASE_62 == 62
  56 # define LOCALHOST_MAX  16
  57 #else
  58 # define LOCALHOST_MAX  10
  59 #endif
  60
  61 /* If not overridden by os.h, dynamic libraries have filenames ending .so */
  62 #ifndef DYNLIB_FN_EXT
  63 # define DYNLIB_FN_EXT "so"
  64 #endif
  65
  66 /* ANSI C standard includes */
  67
  68 #include <ctype.h>
  69 #include <locale.h>
  70 #include <math.h>
  71 #include <signal.h>
  72 #include <stdarg.h>
  73 #include <stddef.h>
  74 #include <stdio.h>
  75 #include <stdlib.h>
  76 #include <string.h>
  77 #include <time.h>
  78
  79 /* Unix includes */
  80
  81 #include <errno.h>
  82 #if defined(__svr4__) && defined(__sparc) && ! defined(__EXTENSIONS__)
  83 # define __EXTENSIONS__  /* so that SunOS 5 gets NGROUPS_MAX */
  84 # include <limits.h>
  85 # undef  __EXTENSIONS__
  86 #else
  87 # include <limits.h>
  88 #endif
  89
  90 /* C99 integer types, figure out how to undo this if needed for older systems */
  91
  92 #include <inttypes.h>
  93
  94 /* Just in case some aged system doesn't define them... */
  95
  96 #ifndef INT_MAX
  97 # define INT_MAX 2147483647
  98 #endif
  99
 100 #ifndef INT_MIN
 101 # define INT_MIN (-INT_MAX - 1)
 102 #endif
 103
 104 #ifndef SHRT_MAX
 105 # define SHRT_MAX 32767
 106 #endif
 107
 108 #ifndef UCHAR_MAX
 109 # define UCHAR_MAX 255
 110 #endif
 111
 112
 113 /* To match int_eximarith_t.  Define in OS/os.h-<your-system> to override. */
 114 #ifndef EXIM_ARITH_MAX
 115 # define EXIM_ARITH_MAX ((int_eximarith_t)9223372036854775807LL)
 116 #endif
 117 #ifndef EXIM_ARITH_MIN
 118 # define EXIM_ARITH_MIN (-EXIM_ARITH_MAX - 1)
 119 #endif
 120
 121 /* Some systems have PATH_MAX and some have MAX_PATH_LEN. */
 122
 123 #ifndef PATH_MAX
 124 # ifdef MAX_PATH_LEN
 125 #  define PATH_MAX MAX_PATH_LEN
 126 # else
 127 #  define PATH_MAX 1024
 128 # endif
 129 #endif
 130
 131 #include <sys/types.h>
 132 #include <sys/file.h>
 133 #include <dirent.h>
 134 #include <netdb.h>
 135 #ifndef NO_POLL_H
 136 # include <poll.h>
 137 #endif
 138 #include <pwd.h>
 139 #include <grp.h>
 140 #include <syslog.h>
 141
 142 /* Not all systems have flock() available. Those that do must define LOCK_SH
 143 in sys/file.h. */
 144
 145 #ifndef LOCK_SH
 146 # define NO_FLOCK
 147 #endif
 148
 149 #ifndef NO_SYSEXITS        /* some OS don't have this */
 150 # include <sysexits.h>
 151 #endif
 152
 153 /* A few OS don't have socklen_t; their os.h files define EXIM_SOCKLEN_T to
 154 be size_t or whatever. We used to use SOCKLEN_T, but then it was discovered
 155 that this is used by the AIX include files. */
 156
 157 #ifndef EXIM_SOCKLEN_T
 158 # define EXIM_SOCKLEN_T socklen_t
 159 #endif
 160
 161 /* Ensure that the sysexits we reference are defined */
 162
 163 #ifndef EX_UNAVAILABLE
 164 # define EX_UNAVAILABLE 69        /* service unavailable; used for execv fail */
 165 #endif
 166 #ifndef EX_CANTCREAT
 167 # define EX_CANTCREAT   73        /* can't create file: treat as temporary */
 168 #endif
 169 #ifndef EX_TEMPFAIL
 170 # define EX_TEMPFAIL    75        /* temp failure; user is invited to retry */
 171 #endif
 172 #ifndef EX_CONFIG
 173 # define EX_CONFIG      78        /* configuration error */
 174 #endif
 175
 176 /* This one is not in any sysexits file that I've come across */
 177
 178 #define EX_EXECFAILED 127        /* execve() failed */
 179
 180
 181 #include <sys/time.h>
 182 #include <sys/param.h>
 183
 184 #ifndef NO_SYS_RESOURCE_H  /* QNX doesn't have this */
 185 # include <sys/resource.h>
 186 #endif
 187
 188 #include <sys/socket.h>
 189
 190 /* If we are on an IPv6 system, the macro AF_INET6 will have been defined in
 191 the sys/socket.h header. It is helpful to have this defined on an IPv4 system
 192 so that it can appear in the code, even if it is never actually used when
 193 the code is run. It saves some #ifdef occurrences. */
 194
 195 #ifndef AF_INET6
 196 # define AF_INET6 24
 197 #endif
 198
 199 #include <sys/ioctl.h>
 200
 201 /* The new standard is statvfs; some OS have statfs. For statvfs the block
 202 counts must be multiplied by the "fragment size" f_frsize to get the actual
 203 size. In other cases the value seems to be f_bsize (which is sometimes the only
 204 block size), so we use a macro to get that instead.
 205
 206 Also arrange to be able to cut it out altogether for way-out OS that don't have
 207 anything. I've indented a bit here to try to make the mess a bit more
 208 intelligible. Note that simply defining one name to be another when
 209 HAVE_SYS_STATVFS_H is not set will not work if the system has a statvfs macro
 210 or a macro with entries f_frsize and f_bsize. */
 211
 212 #ifdef HAVE_STATFS
 213   #ifdef HAVE_SYS_STATVFS_H
 214     #include <sys/statvfs.h>
 215     #define STATVFS statvfs
 216     #define F_FRSIZE f_frsize
 217   #else
 218     #define STATVFS statfs
 219     #define F_FRSIZE f_bsize
 220     #ifdef HAVE_SYS_VFS_H
 221       #include <sys/vfs.h>
 222       #ifdef HAVE_SYS_STATFS_H
 223       #include <sys/statfs.h>
 224       #endif
 225     #endif
 226     #ifdef HAVE_SYS_MOUNT_H
 227     #include <sys/mount.h>
 228     #endif
 229   #endif
 230
 231   /* Macros for the fields for the available space for non-superusers; define
 232   these only if the OS header has not. Not all OS have f_favail; those that
 233   are known to have it define F_FAVAIL as f_favail. The default is to use
 234   f_free. */
 235
 236   #ifndef F_BAVAIL
 237   # define F_BAVAIL f_bavail
 238   #endif
 239
 240   #ifndef F_FAVAIL
 241   # define F_FAVAIL f_ffree
 242   #endif
 243
 244   /* All the systems I've been able to look at seem to have F_FILES */
 245
 246   #ifndef F_FILES
 247   # define F_FILES  f_files
 248   #endif
 249
 250 #endif
 251
 252
 253 #ifndef  SIOCGIFCONF   /* HACK for SunOS 5 */
 254 # include <sys/sockio.h>
 255 #endif
 256
 257 #include <sys/stat.h>
 258 #include <sys/wait.h>
 259 #include <sys/utsname.h>
 260 #include <fcntl.h>
 261
 262 /* There's a shambles in IRIX6 - it defines EX_OK in unistd.h which conflicts
 263 with the definition in sysexits.h. Exim does not actually use this macro, so we
 264 just undefine it. It would be nice to be able to re-instate the definition from
 265 sysexits.h if there is no definition in unistd.h, but I do not think there is a
 266 way to do this in C because macro definitions are not scanned for other macros
 267 at definition time. [The code here used to assume they were, until I was
 268 disabused of the notion. Luckily, since EX_OK is not used, it didn't matter.] */
 269
 270 #ifdef EX_OK
 271 # undef EX_OK
 272 #endif
 273
 274 #include <unistd.h>
 275
 276 #include <utime.h>
 277 #ifndef NO_NET_IF_H
 278 # include <net/if.h>
 279 #endif
 280 #include <sys/un.h>
 281 #include <netinet/in.h>
 282 #include <netinet/tcp.h>
 283 #include <arpa/inet.h>
 284 #include <arpa/nameser.h>
 285
 286
 287 /* While IPv6 is still young the definitions of T_AAAA and T_A6 may not be
 288 included in arpa/nameser.h. Fudge them here. */
 289
 290 #ifndef T_AAAA
 291 #define T_AAAA 28
 292 #endif
 293
 294 #ifndef T_A6
 295 #define T_A6 38
 296 #endif
 297
 298 /* Ancient systems (e.g. SunOS4) don't appear to have T_TXT defined in their
 299 header files. I don't suppose they have T_SRV either. */
 300
 301 #ifndef T_TXT
 302 # define T_TXT 16
 303 #endif
 304
 305 #ifndef T_SRV
 306 # define T_SRV 33
 307 #endif
 308
 309 /* Many systems do not have T_SPF. */
 310
 311 #ifndef T_SPF
 312 # define T_SPF 99
 313 #endif
 314
 315 /* New TLSA record for DANE */
 316 #ifndef T_TLSA
 317 # define T_TLSA 52
 318 #endif
 319 #define MAX_TLSA_EXPANDED_SIZE 8192
 320
 321 /* It seems that some versions of arpa/nameser.h don't define *any* of the
 322 T_xxx macros, which seem to be non-standard nowadays. Just to be on the safe
 323 side, put in definitions for all the ones that Exim uses. */
 324
 325 #ifndef T_A
 326 # define T_A 1
 327 #endif
 328
 329 #ifndef T_CNAME
 330 # define T_CNAME 5
 331 #endif
 332
 333 #ifndef T_SOA
 334 # define T_SOA 6
 335 #endif
 336
 337 #ifndef T_MX
 338 # define T_MX 15
 339 #endif
 340
 341 #ifndef T_NS
 342 # define T_NS 2
 343 #endif
 344
 345 #ifndef T_PTR
 346 # define T_PTR 12
 347 #endif
 348
 349
 350 /* We define a few private types for special DNS lookups:
 351
 352  . T_ZNS gets the nameservers of the enclosing zone of a domain
 353
 354  . T_MXH gets the MX hostnames only (without their priorities)
 355
 356  . T_CSA gets the domain's Client SMTP Authorization SRV record
 357
 358  . T_ADDRESSES looks up both AAAA (or A6) and A records
 359
 360 If any of these names appear in the RRtype list at:
 361   <http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml>
 362 then we should rename Exim's private type away from the conflict.
 363 */
 364
 365 #define T_ZNS (-1)
 366 #define T_MXH (-2)
 367 #define T_CSA (-3)
 368 #define T_ADDRESSES (-4)
 369
 370 /* The resolv.h header defines __P(x) on some Solaris 2.5.1 systems (without
 371 checking that it is already defined, in fact). This conflicts with other
 372 headers that behave likewise (see below), leading to compiler warnings. Arrange
 373 to undefine it if resolv.h defines it. */
 374
 375 #if defined(__P)
 376 # define __P_WAS_DEFINED_BEFORE_RESOLV
 377 #endif
 378
 379 #include <resolv.h>
 380
 381 #if defined(__P) && ! defined (__P_WAS_DEFINED_BEFORE_RESOLV)
 382 # undef __P
 383 #endif
 384
 385 /* If not defined by os.h, we do nothing special to push DNS resolver state
 386 back to be available by the classic resolver routines.  Also, provide
 387 prototype for our get routine, unless defined away. */
 388
 389 #ifndef os_put_dns_resolver_res
 390 # define os_put_dns_resolver_res(R) do {/**/} while(0)
 391 #endif
 392 #ifndef os_get_dns_resolver_res
 393 res_state os_get_dns_resolver_res(void);
 394 #endif
 395
 396 /* These three are to support the IP option logging code. Linux is
 397 different to everyone else and there are also other systems which don't
 398 have netinet/ip_var.h, so there's a general macro to control its inclusion. */
 399
 400 #include <netinet/in_systm.h>
 401 #include <netinet/ip.h>
 402
 403 #ifndef NO_IP_VAR_H
 404 # include <netinet/ip_var.h>
 405 #endif
 406
 407 /* Linux (and some others) uses a different type for the 2nd argument of
 408 iconv(). It's os.h file defines ICONV_ARG2_TYPE. For the rest, define a default
 409 here. */
 410
 411 #ifndef ICONV_ARG2_TYPE
 412 # define ICONV_ARG2_TYPE char **
 413 #endif
 414
 415 /* One OS uses a different type for the 5th argument of getsockopt */
 416
 417 #ifndef GETSOCKOPT_ARG5_TYPE
 418 # define GETSOCKOPT_ARG5_TYPE socklen_t *
 419 #endif
 420
 421 /* One operating system uses a different type for the 2nd argument of select().
 422 Its os.h file defines SELECT_ARG2_TYPE. For the rest, define a default here. */
 423
 424 #ifndef SELECT_ARG2_TYPE
 425 # define SELECT_ARG2_TYPE fd_set
 426 #endif
 427
 428 /* One operating system uses a different type for the 4th argument of
 429 dn_expand(). Its os.h file defines DN_EXPAND_ARG4_TYPE. For the rest, define a
 430 default here. */
 431
 432 #ifndef DN_EXPAND_ARG4_TYPE
 433 # define DN_EXPAND_ARG4_TYPE char *
 434 #endif
 435
 436 /* One operating system defines a different type for the yield of inet_addr().
 437 In Exim code, its value is always assigned to the s_addr members of address
 438 structures. Casting the yield to the type of s_addr should fix the problem,
 439 since the size of the data is correct. Just in case this ever has to be
 440 changed, use a macro for the type, and define it here so that it is possible to
 441 use different values for specific OS if ever necessary. */
 442
 443 #ifndef S_ADDR_TYPE
 444 # define S_ADDR_TYPE u_long
 445 #endif
 446
 447 /* (At least) one operating system (Solaris) defines a different type for the
 448 second argument of pam_converse() - the difference is the absence of "const".
 449 Its os.h file defines PAM_CONVERSE_ARG2_TYPE. For the rest, define a default
 450 here. */
 451
 452 #ifndef PAM_CONVERSE_ARG2_TYPE
 453 # define PAM_CONVERSE_ARG2_TYPE const struct pam_message
 454 #endif
 455
 456 /* One operating system (SunOS4) defines getc, ungetc, feof, and ferror as
 457 macros and not as functions. Exim needs them to be assignable functions. This
 458 flag gets set to cause this to be sorted out here. */
 459
 460 #ifdef FUDGE_GETC_AND_FRIENDS
 461 # undef getc
 462 extern int getc(FILE *);
 463 # undef ungetc
 464 extern int ungetc(int, FILE *);
 465 # undef feof
 466 extern int feof(FILE *);
 467 # undef ferror
 468 extern int ferror(FILE *);
 469 #endif
 470
 471 /* The header from the PCRE regex package */
 472
 473 #include <pcre.h>
 474
 475 /* Exim includes are in several files. Note that local_scan.h #includes
 476 config.h, mytypes.h, and store.h, so we don't need to mention them explicitly.
 477 */
 478
 479 #include "local_scan.h"
 480 #include "macros.h"
 481 #include "dbstuff.h"
 482 #include "structs.h"
 483 #include "blob.h"
 484 #include "globals.h"
 485 #include "hash.h"
 486 #include "functions.h"
 487 #include "dbfunctions.h"
 488 #include "osfunctions.h"
 489
 490 #ifdef EXPERIMENTAL_BRIGHTMAIL
 491 # include "bmi_spam.h"
 492 #endif
 493 #ifdef SUPPORT_SPF
 494 # include "spf.h"
 495 #endif
 496 #ifdef EXPERIMENTAL_SRS
 497 # include "srs.h"
 498 #endif
 499 #ifndef DISABLE_DKIM
 500 # include "dkim.h"
 501 #endif
 502 #ifdef EXPERIMENTAL_DMARC
 503 # include "dmarc.h"
 504 # include <opendmarc/dmarc.h>
 505 #endif
 506
 507 /* The following stuff must follow the inclusion of config.h because it
 508 requires various things that are set therein. */
 509
 510 #if HAVE_ICONV             /* Not all OS have this */
 511 # include <iconv.h>
 512 #endif
 513
 514 #if defined(USE_READLINE) || defined(EXPAND_DLFUNC) || defined (LOOKUP_MODULE_DIR)
 515 # include <dlfcn.h>
 516 #endif
 517
 518 #ifdef ENABLE_DISABLE_FSYNC
 519 # define EXIMfsync(f) (disable_fsync? 0 : fsync(f))
 520 #else
 521 # define EXIMfsync(f) fsync(f)
 522 #endif
 523
 524 /* Backward compatibility; LOOKUP_LSEARCH now includes all three */
 525
 526 #if (!defined LOOKUP_LSEARCH) && (defined LOOKUP_WILDLSEARCH || defined LOOKUP_NWILDLSEARCH)
 527 # define LOOKUP_LSEARCH yes
 528 #endif
 529
 530 /* Define a union to hold either an IPv4 or an IPv6 sockaddr structure; this
 531 simplifies some of the coding.  We include the sockaddr to reduce type-punning
 532 issues in C99. */
 533
 534 union sockaddr_46 {
 535   struct sockaddr_in v4;
 536   #if HAVE_IPV6
 537   struct sockaddr_in6 v6;
 538   #endif
 539   struct sockaddr v0;
 540 };
 541
 542 /* If SUPPORT_TLS is not defined, ensure that USE_GNUTLS is also not defined
 543 so that if USE_GNUTLS *is* set, we can assume SUPPORT_TLS is also set.
 544 Likewise, OSCP, AUTH_TLS and CERTNAMES cannot be supported. */
 545
 546 #ifndef SUPPORT_TLS
 547 # undef USE_GNUTLS
 548 # ifndef DISABLE_OCSP
 549 #  define DISABLE_OCSP
 550 # endif
 551 # undef EXPERIMENTAL_CERTNAMES
 552 # undef AUTH_TLS
 553 #endif
 554
 555 /* If SPOOL_DIRECTORY, LOG_FILE_PATH or PID_FILE_PATH have not been defined,
 556 set them to the null string. */
 557
 558 #ifndef SPOOL_DIRECTORY
 559   #define SPOOL_DIRECTORY ""
 560 #endif
 561 #ifndef LOG_FILE_PATH
 562   #define LOG_FILE_PATH ""
 563 #endif
 564 #ifndef PID_FILE_PATH
 565   #define PID_FILE_PATH ""
 566 #endif
 567
 568 /* The EDQUOT error code isn't universally available, though it is widespread.
 569 There is a particular shambles in SunOS5, where it did not exist originally,
 570 but got installed with a particular patch for Solaris 2.4. There is a
 571 configuration variable for specifying what the system's "over quota" error is,
 572 which will end up in config.h if supplied in OS/Makefile-xxx. If it is not set,
 573 default to EDQUOT if it exists, otherwise ENOSPC. */
 574
 575 #ifndef ERRNO_QUOTA
 576 # ifdef  EDQUOT
 577 #  define ERRNO_QUOTA EDQUOT
 578 # else
 579 #  define ERRNO_QUOTA ENOSPC
 580 # endif
 581 #endif
 582
 583 /* DANE w/o DNSSEC is useless */
 584 #if defined(SUPPORT_DANE) && defined(DISABLE_DNSSEC)
 585 # error DANE support requires DNSSEC support
 586 #endif
 587
 588 /* Some platforms (FreeBSD, OpenBSD, Solaris) do not seem to define this */
 589
 590 #ifndef POLLRDHUP
 591 # define POLLRDHUP (POLLIN | POLLHUP)
 592 #endif
 593
 594 /* Some platforms (Darwin) have to define a larger limit on groups membership */
 595
 596 #ifndef EXIM_GROUPLIST_SIZE
 597 # define EXIM_GROUPLIST_SIZE NGROUPS_MAX
 598 #endif
 599
 600 #endif
 601 /* End of exim.h */