6e88b844a51bfa80c4cec0efcd4111df3186528e
[exim.git] / src / src / os.c
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 #ifdef STAND_ALONE
9 # include <signal.h>
10 # include <stdio.h>
11 # include <time.h>
12 #endif
13
14 #ifndef CS
15 # define CS (char *)
16 # define US (unsigned char *)
17 #endif
18
19 /* This source file contains "default" system-dependent functions which
20 provide functionality (or lack of it) in cases where the OS-specific os.c
21 file has not. Some of them are tailored by macros defined in os.h files. */
22
23
24 #ifndef OS_RESTARTING_SIGNAL
25 /*************************************************
26 * Set up restarting signal *
27 *************************************************/
28
29 /* This function has the same functionality as the ANSI C signal() function,
30 except that it arranges that, if the signal happens during a system call, the
31 system call gets restarted. (Also, it doesn't return a result.) Different
32 versions of Unix have different defaults, and different ways of setting up a
33 restarting signal handler. If the functionality is not available, the signal
34 should be set to be ignored. This function is used only for catching SIGUSR1.
35 */
36
37 void
38 os_restarting_signal(int sig, void (*handler)(int))
39 {
40 /* Many systems have the SA_RESTART sigaction for specifying that a signal
41 should restart system calls. These include SunOS5, AIX, BSDI, IRIX, FreeBSD,
42 OSF1, Linux and HP-UX 10 (but *not* HP-UX 9). */
43
44 #ifdef SA_RESTART
45 struct sigaction act;
46 act.sa_handler = handler;
47 sigemptyset(&(act.sa_mask));
48 act.sa_flags = SA_RESTART;
49 sigaction(sig, &act, NULL);
50
51 #ifdef STAND_ALONE
52 printf("Used SA_RESTART\n");
53 #endif
54
55 /* SunOS4 and Ultrix default to non-interruptable signals, with SV_INTERRUPT
56 for making them interruptable. This seems to be a dying fashion. */
57
58 #elif defined SV_INTERRUPT
59 signal(sig, handler);
60
61 #ifdef STAND_ALONE
62 printf("Used default signal()\n");
63 #endif
64
65
66 /* If neither SA_RESTART nor SV_INTERRUPT is available we don't know how to
67 set up a restarting signal, so simply suppress the facility. */
68
69 #else
70 signal(sig, SIG_IGN);
71
72 #ifdef STAND_ALONE
73 printf("Used SIG_IGN\n");
74 #endif
75
76 #endif
77 }
78
79 #endif /* OS_RESTARTING_SIGNAL */
80
81
82 #ifndef OS_NON_RESTARTING_SIGNAL
83 /*************************************************
84 * Set up non-restarting signal *
85 *************************************************/
86
87 /* This function has the same functionality as the ANSI C signal() function,
88 except that it arranges that, if the signal happens during a system call, the
89 system call gets interrupted. (Also, it doesn't return a result.) Different
90 versions of Unix have different defaults, and different ways of setting up a
91 non-restarting signal handler. For systems for which we don't know what to do,
92 just use the normal signal() function and hope for the best. */
93
94 void
95 os_non_restarting_signal(int sig, void (*handler)(int))
96 {
97 /* Many systems have the SA_RESTART sigaction for specifying that a signal
98 should restart system calls. These include SunOS5, AIX, BSDI, IRIX, FreeBSD,
99 OSF1, Linux and HP-UX 10 (but *not* HP-UX 9). */
100
101 #ifdef SA_RESTART
102 struct sigaction act;
103 act.sa_handler = handler;
104 sigemptyset(&(act.sa_mask));
105 act.sa_flags = 0;
106 sigaction(sig, &act, NULL);
107
108 #ifdef STAND_ALONE
109 printf("Used sigaction() with flags = 0\n");
110 #endif
111
112 /* SunOS4 and Ultrix default to non-interruptable signals, with SV_INTERRUPT
113 for making them interruptable. This seems to be a dying fashion. */
114
115 #elif defined SV_INTERRUPT
116 struct sigvec sv;
117 sv.sv_handler = handler;
118 sv.sv_flags = SV_INTERRUPT;
119 sv.sv_mask = -1;
120 sigvec(sig, &sv, NULL);
121
122 #ifdef STAND_ALONE
123 printf("Used sigvec() with flags = SV_INTERRUPT\n");
124 #endif
125
126 /* If neither SA_RESTART nor SV_INTERRUPT is available we don't know how to
127 set up a restarting signal, so just use the standard signal() function. */
128
129 #else
130 signal(sig, handler);
131
132 #ifdef STAND_ALONE
133 printf("Used default signal()\n");
134 #endif
135
136 #endif
137 }
138
139 #endif /* OS_NON_RESTARTING_SIGNAL */
140
141
142
143 #ifdef STRERROR_FROM_ERRLIST
144 /*************************************************
145 * Provide strerror() for non-ANSI libraries *
146 *************************************************/
147
148 /* Some old-fashioned systems still around (e.g. SunOS4) don't have strerror()
149 in their libraries, but can provide the same facility by this simple
150 alternative function. */
151
152 char *
153 strerror(int n)
154 {
155 if (n < 0 || n >= sys_nerr) return "unknown error number";
156 return sys_errlist[n];
157 }
158 #endif /* STRERROR_FROM_ERRLIST */
159
160
161
162 #ifndef OS_STRSIGNAL
163 /*************************************************
164 * Provide strsignal() for systems without *
165 *************************************************/
166
167 /* Some systems have strsignal() to turn signal numbers into names; others
168 may have other means of doing this. This function is used for those systems
169 that have nothing. It provides a basic translation for the common standard
170 signal numbers. I've been extra cautious with the ifdef's here. Probably more
171 than is necessary... */
172
173 const char *
174 os_strsignal(const int n)
175 {
176 switch (n)
177 {
178 #ifdef SIGHUP
179 case SIGHUP: return "hangup";
180 #endif
181
182 #ifdef SIGINT
183 case SIGINT: return "interrupt";
184 #endif
185
186 #ifdef SIGQUIT
187 case SIGQUIT: return "quit";
188 #endif
189
190 #ifdef SIGILL
191 case SIGILL: return "illegal instruction";
192 #endif
193
194 #ifdef SIGTRAP
195 case SIGTRAP: return "trace trap";
196 #endif
197
198 #ifdef SIGABRT
199 case SIGABRT: return "abort";
200 #endif
201
202 #ifdef SIGEMT
203 case SIGEMT: return "EMT instruction";
204 #endif
205
206 #ifdef SIGFPE
207 case SIGFPE: return "arithmetic exception";
208 #endif
209
210 #ifdef SIGKILL
211 case SIGKILL: return "killed";
212 #endif
213
214 #ifdef SIGBUS
215 case SIGBUS: return "bus error";
216 #endif
217
218 #ifdef SIGSEGV
219 case SIGSEGV: return "segmentation fault";
220 #endif
221
222 #ifdef SIGSYS
223 case SIGSYS: return "bad system call";
224 #endif
225
226 #ifdef SIGPIPE
227 case SIGPIPE: return "broken pipe";
228 #endif
229
230 #ifdef SIGALRM
231 case SIGALRM: return "alarm";
232 #endif
233
234 #ifdef SIGTERM
235 case SIGTERM: return "terminated";
236 #endif
237
238 #ifdef SIGUSR1
239 case SIGUSR1: return "user signal 1";
240 #endif
241
242 #ifdef SIGUSR2
243 case SIGUSR2: return "user signal 2";
244 #endif
245
246 #ifdef SIGCHLD
247 case SIGCHLD: return "child stop or exit";
248 #endif
249
250 #ifdef SIGPWR
251 case SIGPWR: return "power fail/restart";
252 #endif
253
254 #ifdef SIGURG
255 case SIGURG: return "urgent condition on I/O channel";
256 #endif
257
258 #ifdef SIGSTOP
259 case SIGSTOP: return "stop";
260 #endif
261
262 #ifdef SIGTSTP
263 case SIGTSTP: return "stop from tty";
264 #endif
265
266 #ifdef SIGXCPU
267 case SIGXCPU: return "exceeded CPU limit";
268 #endif
269
270 #ifdef SIGXFSZ
271 case SIGXFSZ: return "exceeded file size limit";
272 #endif
273
274 default: return "unrecognized signal number";
275 }
276 }
277 #endif /* OS_STRSIGNAL */
278
279
280
281 #ifndef OS_STREXIT
282 /*************************************************
283 * Provide strexit() for systems without *
284 *************************************************/
285
286 /* Actually, I don't know of any system that has a strexit() function to turn
287 exit codes into text, but this function is implemented this way so that if any
288 OS does have such a thing, it could be used instead of this build-in one. */
289
290 const char *
291 os_strexit(const int n)
292 {
293 switch (n)
294 {
295 /* On systems without sysexits.h we can assume only those exit codes
296 that are given a default value in exim.h. */
297
298 #ifndef NO_SYSEXITS
299 case EX_USAGE: return "(could mean usage or syntax error)";
300 case EX_DATAERR: return "(could mean error in input data)";
301 case EX_NOINPUT: return "(could mean input data missing)";
302 case EX_NOUSER: return "(could mean user nonexistent)";
303 case EX_NOHOST: return "(could mean host nonexistent)";
304 case EX_SOFTWARE: return "(could mean internal software error)";
305 case EX_OSERR: return "(could mean internal operating system error)";
306 case EX_OSFILE: return "(could mean system file missing)";
307 case EX_IOERR: return "(could mean input/output error)";
308 case EX_PROTOCOL: return "(could mean protocol error)";
309 case EX_NOPERM: return "(could mean permission denied)";
310 #endif
311
312 case EX_EXECFAILED: return "(could mean unable to exec or command does not exist)";
313 case EX_UNAVAILABLE: return "(could mean service or program unavailable)";
314 case EX_CANTCREAT: return "(could mean can't create output file)";
315 case EX_TEMPFAIL: return "(could mean temporary error)";
316 case EX_CONFIG: return "(could mean configuration error)";
317 default: return "";
318 }
319 }
320 #endif /* OS_STREXIT */
321
322
323
324
325 /***********************************************************
326 * Load average function *
327 ***********************************************************/
328
329 /* Although every Unix seems to have a different way of getting the load
330 average, a number of them have things in common. Some common variants are
331 provided below, but if an OS has unique requirements it can be handled in
332 a specific os.c file. What is required is a function called os_getloadavg
333 which takes no arguments and passes back the load average * 1000 as an int,
334 or -1 if no data is available. */
335
336
337 /* ----------------------------------------------------------------------- */
338 /* If the OS has got a BSD getloadavg() function, life is very easy. */
339
340 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_BSD_GETLOADAVG)
341 #define OS_LOAD_AVERAGE
342
343 int
344 os_getloadavg(void)
345 {
346 double avg;
347 int loads = getloadavg (&avg, 1);
348 if (loads != 1) return -1;
349 return (int)(avg * 1000.0);
350 }
351 #endif
352 /* ----------------------------------------------------------------------- */
353
354
355
356 /* ----------------------------------------------------------------------- */
357 /* Only SunOS5 has the kstat functions as far as I know, but put the code
358 here as there is the -hal variant, and other systems might follow this road one
359 day. */
360
361 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_KSTAT)
362 #define OS_LOAD_AVERAGE
363
364 #include <kstat.h>
365
366 int
367 os_getloadavg(void)
368 {
369 int avg;
370 kstat_ctl_t *kc;
371 kstat_t *ksp;
372 kstat_named_t *kn;
373
374 if ((kc = kstat_open()) == NULL ||
375 (ksp = kstat_lookup(kc, LOAD_AVG_KSTAT_MODULE, 0, LOAD_AVG_KSTAT))
376 == NULL ||
377 kstat_read(kc, ksp, NULL) < 0 ||
378 (kn = kstat_data_lookup(ksp, LOAD_AVG_SYMBOL)) == NULL)
379 return -1;
380
381 avg = (int)(((double)(kn->LOAD_AVG_FIELD)/FSCALE) * 1000.0);
382
383 kstat_close(kc);
384 return avg;
385 }
386
387 #endif
388 /* ----------------------------------------------------------------------- */
389
390
391
392 /* ----------------------------------------------------------------------- */
393 /* Handle OS where a kernel symbol has to be read from /dev/kmem */
394
395 #if !defined(OS_LOAD_AVERAGE) && defined(HAVE_DEV_KMEM)
396 #define OS_LOAD_AVERAGE
397
398 #include <nlist.h>
399
400 static int avg_kd = -1;
401 static long avg_offset;
402
403 int
404 os_getloadavg(void)
405 {
406 LOAD_AVG_TYPE avg;
407
408 if (avg_kd < 0)
409 {
410 struct nlist nl[2];
411 nl[0].n_name = LOAD_AVG_SYMBOL;
412 nl[1].n_name = "";
413 nlist (KERNEL_PATH, nl);
414 avg_offset = (long)nl[0].n_value;
415 avg_kd = open ("/dev/kmem", 0);
416 if (avg_kd < 0) return -1;
417 (void) fcntl(avg_kd, F_SETFD, FD_CLOEXEC);
418 }
419
420 if (lseek (avg_kd, avg_offset, 0) == -1L
421 || read (avg_kd, CS (&avg), sizeof (avg)) != sizeof(avg))
422 return -1;
423
424 return (int)(((double)avg/FSCALE)*1000.0);
425 }
426
427 #endif
428 /* ----------------------------------------------------------------------- */
429
430
431
432 /* ----------------------------------------------------------------------- */
433 /* If nothing is known about this OS, then the load average facility is
434 not available. */
435
436 #ifndef OS_LOAD_AVERAGE
437
438 int
439 os_getloadavg(void)
440 {
441 return -1;
442 }
443
444 #endif
445
446 /* ----------------------------------------------------------------------- */
447
448
449
450 #if !defined FIND_RUNNING_INTERFACES
451 /*************************************************
452 * Find all the running network interfaces *
453 *************************************************/
454
455 /* Finding all the running interfaces is something that has os-dependent
456 tweaks, even in the IPv4 case, and it gets worse for IPv6, which is why this
457 code is now in the os-dependent source file. There is a common function which
458 works on most OS (except IRIX) for IPv4 interfaces, and, with some variations
459 controlled by macros, on at least one OS for IPv6 and IPv4 interfaces. On Linux
460 with IPv6, the common function is used for the IPv4 interfaces and additional
461 code used for IPv6. Consequently, the real function is called
462 os_common_find_running_interfaces() so that it can be called from the Linux
463 function. On non-Linux systems, the macro for os_find_running_interfaces just
464 calls the common function; on Linux it calls the Linux function.
465
466 This function finds the addresses of all the running interfaces on the machine.
467 A chain of blocks containing the textual form of the addresses is returned.
468
469 getifaddrs() provides a sane consistent way to query this on modern OSs,
470 otherwise fall back to a maze of twisty ioctl() calls
471
472 Arguments: none
473 Returns: a chain of ip_address_items, each pointing to a textual
474 version of an IP address, with the port field set to zero
475 */
476
477
478 #ifndef NO_FIND_INTERFACES
479
480 #ifdef HAVE_GETIFADDRS
481
482 #include <ifaddrs.h>
483
484 ip_address_item *
485 os_common_find_running_interfaces(void)
486 {
487 struct ifaddrs *ifalist = NULL;
488 ip_address_item *yield = NULL;
489 ip_address_item *last = NULL;
490 ip_address_item *next;
491
492 if (getifaddrs(&ifalist) != 0)
493 log_write(0, LOG_PANIC_DIE, "Unable to call getifaddrs: %d %s",
494 errno, strerror(errno));
495
496 struct ifaddrs *ifa;
497 for (ifa = ifalist; ifa != NULL; ifa = ifa->ifa_next)
498 {
499 if (ifa->ifa_addr->sa_family != AF_INET
500 #if HAVE_IPV6
501 && ifa->ifa_addr->sa_family != AF_INET6
502 #endif /* HAVE_IPV6 */
503 )
504 continue;
505
506 if ( !(ifa->ifa_flags & IFF_UP) ) /* Only want 'UP' interfaces */
507 continue;
508
509 /* Create a data block for the address, fill in the data, and put it on the
510 chain. */
511
512 next = store_get(sizeof(ip_address_item));
513 next->next = NULL;
514 next->port = 0;
515 (void)host_ntoa(-1, ifa->ifa_addr, next->address, NULL);
516
517 if (yield == NULL)
518 yield = last = next;
519 else
520 {
521 last->next = next;
522 last = next;
523 }
524
525 DEBUG(D_interface) debug_printf("Actual local interface address is %s (%s)\n",
526 last->address, ifa->ifa_name);
527 }
528
529 /* free the list of addresses, and return the chain of data blocks. */
530
531 freeifaddrs (ifalist);
532 return yield;
533 }
534
535 #else /* HAVE_GETIFADDRS */
536
537 /*
538 Problems:
539
540 (1) Solaris 2 has the SIOGIFNUM call to get the number of interfaces, but
541 other OS (including Solaris 1) appear not to. So just screw in a largeish
542 fixed number, defined by MAX_INTERFACES. This is in the config.h file and
543 can be changed in Local/Makefile. Unfortunately, the www addressing scheme
544 means that some hosts have a very large number of virtual interfaces. Such
545 hosts are recommended to set local_interfaces to avoid problems with this.
546
547 (2) If the standard code is run on IRIX, it does not return any alias
548 interfaces. There is special purpose code for that operating system, which
549 uses the sysctl() function. The code is in OS/os.c-IRIX, and this code isn't
550 used on that OS.
551
552 (3) Some experimental/developing OS (e.g. GNU/Hurd) do not have any means
553 of finding the interfaces. If NO_FIND_INTERFACES is set, a fudge-up is used
554 instead.
555
556 (4) Some operating systems set the IP address in what SIOCGIFCONF returns;
557 others do not, and require SIOCGIFADDR to be called to get it. For most of
558 the former, calling the latter does no harm, but it causes grief on Linux and
559 BSD systems in the case of IP aliasing, so a means of cutting it out is
560 provided.
561 */
562
563 /* If there is IPv6 support, and SIOCGLIFCONF is defined, define macros to
564 use these new, longer versions of the old IPv4 interfaces. Otherwise, define
565 the macros to use the historical versions. */
566
567 #if HAVE_IPV6 && defined SIOCGLIFCONF
568 #define V_ifconf lifconf
569 #define V_ifreq lifreq
570 #define V_GIFADDR SIOCGLIFADDR
571 #define V_GIFCONF SIOCGLIFCONF
572 #define V_GIFFLAGS SIOCGLIFFLAGS
573 #define V_ifc_buf lifc_buf
574 #define V_ifc_family lifc_family
575 #define V_ifc_flags lifc_flags
576 #define V_ifc_len lifc_len
577 #define V_ifr_addr lifr_addr
578 #define V_ifr_flags lifr_flags
579 #define V_ifr_name lifr_name
580 #define V_FAMILY_QUERY AF_UNSPEC
581 #define V_family ss_family
582 #else
583 #define V_ifconf ifconf
584 #define V_ifreq ifreq
585 #define V_GIFADDR SIOCGIFADDR
586 #define V_GIFCONF SIOCGIFCONF
587 #define V_GIFFLAGS SIOCGIFFLAGS
588 #define V_ifc_buf ifc_buf
589 #define V_ifc_family ifc_family
590 #define V_ifc_flags ifc_flags
591 #define V_ifc_len ifc_len
592 #define V_ifr_addr ifr_addr
593 #define V_ifr_flags ifr_flags
594 #define V_ifr_name ifr_name
595 #define V_family sa_family
596 #endif
597
598 /* In all cases of IPv6 support, use an IPv6 socket. Otherwise (at least on
599 Solaris 8) the call to read the flags doesn't work for IPv6 interfaces. If
600 we find we can't actually make an IPv6 socket, the code will revert to trying
601 an IPv4 socket. */
602
603 #if HAVE_IPV6
604 #define FAMILY AF_INET6
605 #else
606 #define FAMILY AF_INET
607 #endif
608
609 /* OK, after all that preliminary stuff, here's the code. */
610
611 ip_address_item *
612 os_common_find_running_interfaces(void)
613 {
614 struct V_ifconf ifc;
615 struct V_ifreq ifreq;
616 int vs;
617 ip_address_item *yield = NULL;
618 ip_address_item *last = NULL;
619 ip_address_item *next;
620 char *cp;
621 char buf[MAX_INTERFACES*sizeof(struct V_ifreq)];
622 struct sockaddr *addrp;
623 size_t len = 0;
624 char addrbuf[512];
625
626 /* We have to create a socket in order to do ioctls on it to find out
627 what we want to know. */
628
629 if ((vs = socket(FAMILY, SOCK_DGRAM, 0)) < 0)
630 {
631 #if HAVE_IPV6
632 DEBUG(D_interface)
633 debug_printf("Unable to create IPv6 socket to find interface addresses:\n "
634 "error %d %s\nTrying for an IPv4 socket\n", errno, strerror(errno));
635 vs = socket(AF_INET, SOCK_DGRAM, 0);
636 if (vs < 0)
637 #endif
638 log_write(0, LOG_PANIC_DIE, "Unable to create IPv4 socket to find interface "
639 "addresses: %d %s", errno, strerror(errno));
640 }
641
642 /* Get the interface configuration. Some additional data is required when the
643 new structures are in use. */
644
645 ifc.V_ifc_len = sizeof(buf);
646 ifc.V_ifc_buf = buf;
647
648 #ifdef V_FAMILY_QUERY
649 ifc.V_ifc_family = V_FAMILY_QUERY;
650 ifc.V_ifc_flags = 0;
651 #endif
652
653 if (ioctl(vs, V_GIFCONF, CS &ifc) < 0)
654 log_write(0, LOG_PANIC_DIE, "Unable to get interface configuration: %d %s",
655 errno, strerror(errno));
656
657 /* If the buffer is big enough, the ioctl sets the value of ifc.V_ifc_len to
658 the amount actually used. If the buffer isn't big enough, at least on some
659 operating systems, ifc.V_ifc_len still gets set to correspond to the total
660 number of interfaces, even though they don't all fit in the buffer. */
661
662 if (ifc.V_ifc_len > sizeof(buf))
663 {
664 ifc.V_ifc_len = sizeof(buf);
665 DEBUG(D_interface)
666 debug_printf("more than %d interfaces found: remainder not used\n"
667 "(set MAX_INTERFACES in Local/Makefile and rebuild if you want more)\n",
668 MAX_INTERFACES);
669 }
670
671 /* For each interface, check it is an IP interface, get its flags, and see if
672 it is up; if not, skip.
673
674 BSD systems differ from others in what SIOCGIFCONF returns. Other systems
675 return a vector of ifreq structures whose size is as defined by the structure.
676 BSD systems allow sockaddrs to be longer than their sizeof, which in turn makes
677 the ifreq structures longer than their sizeof. The code below has its origins
678 in amd and ifconfig; it uses the sa_len field of each sockaddr to determine
679 each item's length.
680
681 This is complicated by the fact that, at least on BSD systems, the data in the
682 buffer is not guaranteed to be aligned. Thus, we must first copy the basic
683 struct to some aligned memory before looking at the field in the fixed part to
684 find its length, and then recopy the correct length. */
685
686 for (cp = buf; cp < buf + ifc.V_ifc_len; cp += len)
687 {
688 memcpy(CS &ifreq, cp, sizeof(ifreq));
689
690 #ifndef HAVE_SA_LEN
691 len = sizeof(struct V_ifreq);
692
693 #else
694 len = ((ifreq.ifr_addr.sa_len > sizeof(ifreq.ifr_addr))?
695 ifreq.ifr_addr.sa_len : sizeof(ifreq.ifr_addr)) +
696 sizeof(ifreq.V_ifr_name);
697 if (len > sizeof(addrbuf))
698 log_write(0, LOG_PANIC_DIE, "Address for %s interface is absurdly long",
699 ifreq.V_ifr_name);
700
701 #endif
702
703 /* If not an IP interface, skip */
704
705 if (ifreq.V_ifr_addr.V_family != AF_INET
706 #if HAVE_IPV6
707 && ifreq.V_ifr_addr.V_family != AF_INET6
708 #endif
709 ) continue;
710
711 /* Get the interface flags, and if the interface is down, continue. Formerly,
712 we treated the inability to get the flags as a panic-die error. However, it
713 seems that on some OS (Solaris 9 being the case noted), it is possible to
714 have an interface in this list for which this call fails because the
715 interface hasn't been "plumbed" to any protocol (IPv4 or IPv6). Therefore,
716 we now just treat this case as "down" as well. */
717
718 if (ioctl(vs, V_GIFFLAGS, CS &ifreq) < 0)
719 {
720 continue;
721 /*************
722 log_write(0, LOG_PANIC_DIE, "Unable to get flags for %s interface: %d %s",
723 ifreq.V_ifr_name, errno, strerror(errno));
724 *************/
725 }
726 if ((ifreq.V_ifr_flags & IFF_UP) == 0) continue;
727
728 /* On some operating systems we have to get the IP address of the interface
729 by another call. On others, it's already there, but we must copy the full
730 length because we only copied the basic length above, and anyway,
731 GIFFLAGS may have wrecked the data. */
732
733 #ifndef SIOCGIFCONF_GIVES_ADDR
734 if (ioctl(vs, V_GIFADDR, CS &ifreq) < 0)
735 log_write(0, LOG_PANIC_DIE, "Unable to get IP address for %s interface: "
736 "%d %s", ifreq.V_ifr_name, errno, strerror(errno));
737 addrp = &ifreq.V_ifr_addr;
738
739 #else
740 memcpy(addrbuf, cp + offsetof(struct V_ifreq, V_ifr_addr),
741 len - sizeof(ifreq.V_ifr_name));
742 addrp = (struct sockaddr *)addrbuf;
743 #endif
744
745 /* Create a data block for the address, fill in the data, and put it on the
746 chain. */
747
748 next = store_get(sizeof(ip_address_item));
749 next->next = NULL;
750 next->port = 0;
751 (void)host_ntoa(-1, addrp, next->address, NULL);
752
753 if (yield == NULL) yield = last = next; else
754 {
755 last->next = next;
756 last = next;
757 }
758
759 DEBUG(D_interface) debug_printf("Actual local interface address is %s (%s)\n",
760 last->address, ifreq.V_ifr_name);
761 }
762
763 /* Close the socket, and return the chain of data blocks. */
764
765 (void)close(vs);
766 return yield;
767 }
768
769 #endif /* HAVE_GETIFADDRS */
770
771 #else /* NO_FIND_INTERFACES */
772
773 /* Some experimental or developing OS (e.g. GNU/Hurd) do not have the ioctls,
774 and there is no other way to get a list of the (IP addresses of) local
775 interfaces. We just return the loopback address(es). */
776
777 ip_address_item *
778 os_common_find_running_interfaces(void)
779 {
780 ip_address_item *yield = store_get(sizeof(address_item));
781 yield->address = US"127.0.0.1";
782 yield->port = 0;
783 yield->next = NULL;
784
785 #if HAVE_IPV6
786 yield->next = store_get(sizeof(address_item));
787 yield->next->address = US"::1";
788 yield->next->port = 0;
789 yield->next->next = NULL;
790 #endif
791
792 DEBUG(D_interface) debug_printf("Unable to find local interface addresses "
793 "on this OS: returning loopback address(es)\n");
794 return yield;
795 }
796
797 #endif /* NO_FIND_INTERFACES */
798 #endif /* FIND_RUNNING_INTERFACES */
799
800
801
802
803 /* ----------------------------------------------------------------------- */
804
805 /***********************************************************
806 * DNS Resolver Base Finder *
807 ***********************************************************/
808
809 /* We need to be able to set options for the system resolver(5), historically
810 made available as _res. At least one OS (NetBSD) now no longer provides this
811 directly, instead making you call a function per thread to get a handle.
812 Other OSs handle thread-safe resolver differently, in ways which fail if the
813 programmer creates their own structs. */
814
815 #if !defined(OS_GET_DNS_RESOLVER_RES) && !defined(COMPILE_UTILITY)
816
817 #include <resolv.h>
818
819 /* confirmed that res_state is typedef'd as a struct* on BSD and Linux, will
820 find out how unportable it is on other OSes, but most resolver implementations
821 should be descended from ISC's bind.
822
823 Linux and BSD do:
824 define _res (*__res_state())
825 identically. We just can't rely on __foo functions. It's surprising that use
826 of _res has been as portable as it has, for so long.
827
828 So, since _res works everywhere, and everything can decode the struct, I'm
829 going to gamble that res_state is a typedef everywhere and use that as the
830 return type.
831 */
832
833 res_state
834 os_get_dns_resolver_res(void)
835 {
836 return &_res;
837 }
838
839 #endif /* OS_GET_DNS_RESOLVER_RES */
840
841 /* ----------------------------------------------------------------------- */
842
843 /***********************************************************
844 * unsetenv() *
845 ***********************************************************/
846
847 /* Most modern systems define int unsetenv(const char*),
848 * some don't. */
849
850 #if !defined(OS_UNSETENV)
851 int
852 os_unsetenv(const unsigned char * name)
853 {
854 return unsetenv(CS name);
855 }
856 #endif
857
858 /* ----------------------------------------------------------------------- */
859
860 /***********************************************************
861 * getcwd() *
862 ***********************************************************/
863
864 /* Glibc allows getcwd(NULL, 0) to do auto-allocation. Some systems
865 do auto-allocation, but need the size of the buffer, and others
866 may not even do this. If the OS supports getcwd(NULL, 0) we'll use
867 this, for all other systems we provide our own getcwd() */
868
869 #if !defined(OS_GETCWD)
870 unsigned char *
871 os_getcwd(unsigned char * buffer, size_t size)
872 {
873 return US getcwd(CS buffer, size);
874 }
875 #else
876 #ifndef PATH_MAX
877 # define PATH_MAX 4096
878 #endif
879 unsigned char *
880 os_getcwd(unsigned char * buffer, size_t size)
881 {
882 char * b = CS buffer;
883
884 if (!size) size = PATH_MAX;
885 if (!b && !(b = malloc(size))) return NULL;
886 if (!(b = getcwd(b, size))) return NULL;
887 return buffer ? buffer : realloc(b, strlen(b) + 1);
888 }
889 #endif
890
891 /* ----------------------------------------------------------------------- */
892
893
894
895
896 /*************************************************
897 **************************************************
898 * Stand-alone test program *
899 **************************************************
900 *************************************************/
901
902
903 #ifdef STAND_ALONE
904
905 #ifdef CLOCKS_PER_SEC
906 #define REAL_CLOCK_TICK CLOCKS_PER_SEC
907 #else
908 #ifdef CLK_TCK
909 #define REAL_CLOCK_TICK CLK_TCK
910 #else
911 #define REAL_CLOCK_TICK 1000000 /* SunOS4 */
912 #endif
913 #endif
914
915
916 int main(int argc, char **argv)
917 {
918 char buffer[128];
919 int fd = fileno(stdin);
920 int rc;
921
922 printf("Testing restarting signal; wait for handler message, then type a line\n");
923 strcpy(buffer, "*** default ***\n");
924 os_restarting_signal(SIGALRM, sigalrm_handler);
925 alarm(2);
926 if ((rc = read(fd, buffer, sizeof(buffer))) < 0)
927 printf("No data read\n");
928 else
929 {
930 buffer[rc] = 0;
931 printf("Read: %s", buffer);
932 }
933 alarm(0);
934
935 printf("Testing non-restarting signal; should read no data after handler message\n");
936 strcpy(buffer, "*** default ***\n");
937 os_non_restarting_signal(SIGALRM, sigalrm_handler);
938 alarm(2);
939 if ((rc = read(fd, buffer, sizeof(buffer))) < 0)
940 printf("No data read\n");
941 else
942 {
943 buffer[rc] = 0;
944 printf("Read: %s", buffer);
945 }
946 alarm(0);
947
948 printf("Testing load averages (last test - ^C to kill)\n");
949 for (;;)
950 {
951 int avg;
952 clock_t used;
953 clock_t before = clock();
954 avg = os_getloadavg();
955 used = clock() - before;
956 printf("cpu time = %.2f ", (double)used/REAL_CLOCK_TICK);
957 if (avg < 0)
958 {
959 printf("load average not available\n");
960 break;
961 }
962 printf("load average = %.2f\n", (double)avg/1000.0);
963 sleep(2);
964 }
965 return 0;
966 }
967
968 #endif
969
970 /* End of os.c */