src/src/exim.h

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2016 */
   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 /* If arpa/nameser.h defines a maximum name server packet size, use it,
 288 provided it is greater than 2048. Otherwise go for a default. PACKETSZ was used
 289 for this, but it seems that NS_PACKETSZ is coming into use. */
 290
 291 #if defined(NS_PACKETSZ) && NS_PACKETSZ >= 2048
 292   #define MAXPACKET NS_PACKETSZ
 293 #elif defined(PACKETSZ) && PACKETSZ >= 2048
 294   #define MAXPACKET PACKETSZ
 295 #else
 296   #define MAXPACKET 2048
 297 #endif
 298
 299 /* While IPv6 is still young the definitions of T_AAAA and T_A6 may not be
 300 included in arpa/nameser.h. Fudge them here. */
 301
 302 #ifndef T_AAAA
 303 #define T_AAAA 28
 304 #endif
 305
 306 #ifndef T_A6
 307 #define T_A6 38
 308 #endif
 309
 310 /* Ancient systems (e.g. SunOS4) don't appear to have T_TXT defined in their
 311 header files. I don't suppose they have T_SRV either. */
 312
 313 #ifndef T_TXT
 314 # define T_TXT 16
 315 #endif
 316
 317 #ifndef T_SRV
 318 # define T_SRV 33
 319 #endif
 320
 321 /* Many systems do not have T_SPF. */
 322
 323 #ifndef T_SPF
 324 # define T_SPF 99
 325 #endif
 326
 327 /* New TLSA record for DANE */
 328 #ifndef T_TLSA
 329 # define T_TLSA 52
 330 #endif
 331 #define MAX_TLSA_EXPANDED_SIZE 8192
 332
 333 /* It seems that some versions of arpa/nameser.h don't define *any* of the
 334 T_xxx macros, which seem to be non-standard nowadays. Just to be on the safe
 335 side, put in definitions for all the ones that Exim uses. */
 336
 337 #ifndef T_A
 338 # define T_A 1
 339 #endif
 340
 341 #ifndef T_CNAME
 342 # define T_CNAME 5
 343 #endif
 344
 345 #ifndef T_SOA
 346 # define T_SOA 6
 347 #endif
 348
 349 #ifndef T_MX
 350 # define T_MX 15
 351 #endif
 352
 353 #ifndef T_NS
 354 # define T_NS 2
 355 #endif
 356
 357 #ifndef T_PTR
 358 # define T_PTR 12
 359 #endif
 360
 361
 362 /* We define a few private types for special DNS lookups:
 363
 364  . T_ZNS gets the nameservers of the enclosing zone of a domain
 365
 366  . T_MXH gets the MX hostnames only (without their priorities)
 367
 368  . T_CSA gets the domain's Client SMTP Authorization SRV record
 369
 370  . T_ADDRESSES looks up both AAAA (or A6) and A records
 371
 372 If any of these names appear in the RRtype list at:
 373   <http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml>
 374 then we should rename Exim's private type away from the conflict.
 375 */
 376
 377 #define T_ZNS (-1)
 378 #define T_MXH (-2)
 379 #define T_CSA (-3)
 380 #define T_ADDRESSES (-4)
 381
 382 /* The resolv.h header defines __P(x) on some Solaris 2.5.1 systems (without
 383 checking that it is already defined, in fact). This conflicts with other
 384 headers that behave likewise (see below), leading to compiler warnings. Arrange
 385 to undefine it if resolv.h defines it. */
 386
 387 #if defined(__P)
 388 # define __P_WAS_DEFINED_BEFORE_RESOLV
 389 #endif
 390
 391 #include <resolv.h>
 392
 393 #if defined(__P) && ! defined (__P_WAS_DEFINED_BEFORE_RESOLV)
 394 # undef __P
 395 #endif
 396
 397 /* If not defined by os.h, we do nothing special to push DNS resolver state
 398 back to be available by the classic resolver routines.  Also, provide
 399 prototype for our get routine, unless defined away. */
 400
 401 #ifndef os_put_dns_resolver_res
 402 # define os_put_dns_resolver_res(R) do {/**/} while(0)
 403 #endif
 404 #ifndef os_get_dns_resolver_res
 405 res_state os_get_dns_resolver_res(void);
 406 #endif
 407
 408 /* These three are to support the IP option logging code. Linux is
 409 different to everyone else and there are also other systems which don't
 410 have netinet/ip_var.h, so there's a general macro to control its inclusion. */
 411
 412 #include <netinet/in_systm.h>
 413 #include <netinet/ip.h>
 414
 415 #ifndef NO_IP_VAR_H
 416 # include <netinet/ip_var.h>
 417 #endif
 418
 419 /* Linux (and some others) uses a different type for the 2nd argument of
 420 iconv(). It's os.h file defines ICONV_ARG2_TYPE. For the rest, define a default
 421 here. */
 422
 423 #ifndef ICONV_ARG2_TYPE
 424 # define ICONV_ARG2_TYPE char **
 425 #endif
 426
 427 /* One OS uses a different type for the 5th argument of getsockopt */
 428
 429 #ifndef GETSOCKOPT_ARG5_TYPE
 430 # define GETSOCKOPT_ARG5_TYPE socklen_t *
 431 #endif
 432
 433 /* One operating system uses a different type for the 2nd argument of select().
 434 Its os.h file defines SELECT_ARG2_TYPE. For the rest, define a default here. */
 435
 436 #ifndef SELECT_ARG2_TYPE
 437 # define SELECT_ARG2_TYPE fd_set
 438 #endif
 439
 440 /* One operating system uses a different type for the 4th argument of
 441 dn_expand(). Its os.h file defines DN_EXPAND_ARG4_TYPE. For the rest, define a
 442 default here. */
 443
 444 #ifndef DN_EXPAND_ARG4_TYPE
 445 # define DN_EXPAND_ARG4_TYPE char *
 446 #endif
 447
 448 /* One operating system defines a different type for the yield of inet_addr().
 449 In Exim code, its value is always assigned to the s_addr members of address
 450 structures. Casting the yield to the type of s_addr should fix the problem,
 451 since the size of the data is correct. Just in case this ever has to be
 452 changed, use a macro for the type, and define it here so that it is possible to
 453 use different values for specific OS if ever necessary. */
 454
 455 #ifndef S_ADDR_TYPE
 456 # define S_ADDR_TYPE u_long
 457 #endif
 458
 459 /* (At least) one operating system (Solaris) defines a different type for the
 460 second argument of pam_converse() - the difference is the absence of "const".
 461 Its os.h file defines PAM_CONVERSE_ARG2_TYPE. For the rest, define a default
 462 here. */
 463
 464 #ifndef PAM_CONVERSE_ARG2_TYPE
 465 # define PAM_CONVERSE_ARG2_TYPE const struct pam_message
 466 #endif
 467
 468 /* One operating system (SunOS4) defines getc, ungetc, feof, and ferror as
 469 macros and not as functions. Exim needs them to be assignable functions. This
 470 flag gets set to cause this to be sorted out here. */
 471
 472 #ifdef FUDGE_GETC_AND_FRIENDS
 473 # undef getc
 474 extern int getc(FILE *);
 475 # undef ungetc
 476 extern int ungetc(int, FILE *);
 477 # undef feof
 478 extern int feof(FILE *);
 479 # undef ferror
 480 extern int ferror(FILE *);
 481 #endif
 482
 483 /* The header from the PCRE regex package */
 484
 485 #include <pcre.h>
 486
 487 /* Exim includes are in several files. Note that local_scan.h #includes
 488 config.h, mytypes.h, and store.h, so we don't need to mention them explicitly.
 489 */
 490
 491 #include "local_scan.h"
 492 #include "macros.h"
 493 #include "dbstuff.h"
 494 #include "structs.h"
 495 #include "globals.h"
 496 #include "functions.h"
 497 #include "dbfunctions.h"
 498 #include "osfunctions.h"
 499
 500 #ifdef EXPERIMENTAL_BRIGHTMAIL
 501 # include "bmi_spam.h"
 502 #endif
 503 #ifdef EXPERIMENTAL_SPF
 504 # include "spf.h"
 505 #endif
 506 #ifdef EXPERIMENTAL_SRS
 507 # include "srs.h"
 508 #endif
 509 #ifndef DISABLE_DKIM
 510 # include "dkim.h"
 511 #endif
 512 #ifdef EXPERIMENTAL_DMARC
 513 # include "dmarc.h"
 514 # include <opendmarc/dmarc.h>
 515 #endif
 516
 517 /* The following stuff must follow the inclusion of config.h because it
 518 requires various things that are set therein. */
 519
 520 #if HAVE_ICONV             /* Not all OS have this */
 521 # include <iconv.h>
 522 #endif
 523
 524 #if defined(USE_READLINE) || defined(EXPAND_DLFUNC) || defined (LOOKUP_MODULE_DIR)
 525 # include <dlfcn.h>
 526 #endif
 527
 528 #ifdef ENABLE_DISABLE_FSYNC
 529 # define EXIMfsync(f) (disable_fsync? 0 : fsync(f))
 530 #else
 531 # define EXIMfsync(f) fsync(f)
 532 #endif
 533
 534 /* Backward compatibility; LOOKUP_LSEARCH now includes all three */
 535
 536 #if (!defined LOOKUP_LSEARCH) && (defined LOOKUP_WILDLSEARCH || defined LOOKUP_NWILDLSEARCH)
 537 # define LOOKUP_LSEARCH yes
 538 #endif
 539
 540 /* Define a union to hold either an IPv4 or an IPv6 sockaddr structure; this
 541 simplifies some of the coding.  We include the sockaddr to reduce type-punning
 542 issues in C99. */
 543
 544 union sockaddr_46 {
 545   struct sockaddr_in v4;
 546   #if HAVE_IPV6
 547   struct sockaddr_in6 v6;
 548   #endif
 549   struct sockaddr v0;
 550 };
 551
 552 /* If SUPPORT_TLS is not defined, ensure that USE_GNUTLS is also not defined
 553 so that if USE_GNUTLS *is* set, we can assume SUPPORT_TLS is also set. */
 554
 555 #ifndef SUPPORT_TLS
 556 # undef USE_GNUTLS
 557 #endif
 558
 559 /* If SPOOL_DIRECTORY, LOG_FILE_PATH or PID_FILE_PATH have not been defined,
 560 set them to the null string. */
 561
 562 #ifndef SPOOL_DIRECTORY
 563   #define SPOOL_DIRECTORY ""
 564 #endif
 565 #ifndef LOG_FILE_PATH
 566   #define LOG_FILE_PATH ""
 567 #endif
 568 #ifndef PID_FILE_PATH
 569   #define PID_FILE_PATH ""
 570 #endif
 571
 572 /* The EDQUOT error code isn't universally available, though it is widespread.
 573 There is a particular shambles in SunOS5, where it did not exist originally,
 574 but got installed with a particular patch for Solaris 2.4. There is a
 575 configuration variable for specifying what the system's "over quota" error is,
 576 which will end up in config.h if supplied in OS/Makefile-xxx. If it is not set,
 577 default to EDQUOT if it exists, otherwise ENOSPC. */
 578
 579 #ifndef ERRNO_QUOTA
 580 # ifdef  EDQUOT
 581 #  define ERRNO_QUOTA EDQUOT
 582 # else
 583 #  define ERRNO_QUOTA ENOSPC
 584 # endif
 585 #endif
 586
 587 /* Ensure PATH_MAX is defined */
 588
 589 #ifndef PATH_MAX
 590   #ifdef MAXPATHLEN
 591   # define PATH_MAX MAXPATHLEN
 592   #else
 593   # define PATH_MAX 1024
 594   #endif
 595 #endif
 596
 597 /* DANE w/o DNSSEC is useless */
 598 #if defined(EXPERIMENTAL_DANE) && defined(DISABLE_DNSSEC)
 599   #undef DISABLE_DNSSEC
 600 #endif
 601
 602 #endif
 603 /* End of exim.h */