Recast more internal string routines to use growable-strings
[exim.git] / src / src / host.c
CommitLineData
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1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
f9ba5e22 5/* Copyright (c) University of Cambridge 1995 - 2018 */
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6/* See the file NOTICE for conditions of use and distribution. */
7
8/* Functions for finding hosts, either by gethostbyname(), gethostbyaddr(), or
9directly via the DNS. When IPv6 is supported, getipnodebyname() and
10getipnodebyaddr() may be used instead of gethostbyname() and gethostbyaddr(),
11if the newer functions are available. This module also contains various other
12functions concerned with hosts and addresses, and a random number function,
13used for randomizing hosts with equal MXs but available for use in other parts
14of Exim. */
15
16
17#include "exim.h"
18
19
20/* Static variable for preserving the list of interface addresses in case it is
21used more than once. */
22
23static ip_address_item *local_interface_data = NULL;
24
25
26#ifdef USE_INET_NTOA_FIX
27/*************************************************
28* Replacement for broken inet_ntoa() *
29*************************************************/
30
31/* On IRIX systems, gcc uses a different structure passing convention to the
32native libraries. This causes inet_ntoa() to always yield 0.0.0.0 or
33255.255.255.255. To get round this, we provide a private version of the
34function here. It is used only if USE_INET_NTOA_FIX is set, which should happen
35only when gcc is in use on an IRIX system. Code send to me by J.T. Breitner,
36with these comments:
37
38 code by Stuart Levy
39 as seen in comp.sys.sgi.admin
40
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41August 2005: Apparently this is also needed for AIX systems; USE_INET_NTOA_FIX
42should now be set for them as well.
43
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44Arguments: sa an in_addr structure
45Returns: pointer to static text string
46*/
47
48char *
49inet_ntoa(struct in_addr sa)
50{
51static uschar addr[20];
52sprintf(addr, "%d.%d.%d.%d",
53 (US &sa.s_addr)[0],
54 (US &sa.s_addr)[1],
55 (US &sa.s_addr)[2],
56 (US &sa.s_addr)[3]);
57 return addr;
58}
59#endif
60
61
62
63/*************************************************
64* Random number generator *
65*************************************************/
66
67/* This is a simple pseudo-random number generator. It does not have to be
68very good for the uses to which it is put. When running the regression tests,
69start with a fixed seed.
70
17c76198 71If you need better, see vaguely_random_number() which is potentially stronger,
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72if a crypto library is available, but might end up just calling this instead.
73
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74Arguments:
75 limit: one more than the largest number required
76
77Returns: a pseudo-random number in the range 0 to limit-1
78*/
79
80int
81random_number(int limit)
82{
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83if (limit < 1)
84 return 0;
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85if (random_seed == 0)
86 {
8768d548 87 if (f.running_in_test_harness) random_seed = 42; else
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88 {
89 int p = (int)getpid();
90 random_seed = (int)time(NULL) ^ ((p << 16) | p);
91 }
92 }
93random_seed = 1103515245 * random_seed + 12345;
94return (unsigned int)(random_seed >> 16) % limit;
95}
96
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97/*************************************************
98* Wrappers for logging lookup times *
99*************************************************/
100
101/* When the 'slow_lookup_log' variable is enabled, these wrappers will
102write to the log file all (potential) dns lookups that take more than
103slow_lookup_log milliseconds
104*/
105
106static void
107log_long_lookup(const uschar * type, const uschar * data, unsigned long msec)
108{
109log_write(0, LOG_MAIN, "Long %s lookup for '%s': %lu msec",
110 type, data, msec);
111}
112
113
114/* returns the current system epoch time in milliseconds. */
115static unsigned long
116get_time_in_ms()
117{
118struct timeval tmp_time;
119unsigned long seconds, microseconds;
120
121gettimeofday(&tmp_time, NULL);
122seconds = (unsigned long) tmp_time.tv_sec;
123microseconds = (unsigned long) tmp_time.tv_usec;
124return seconds*1000 + microseconds/1000;
125}
126
127
128static int
129dns_lookup_timerwrap(dns_answer *dnsa, const uschar *name, int type,
130 const uschar **fully_qualified_name)
131{
132int retval;
133unsigned long time_msec;
134
135if (!slow_lookup_log)
136 return dns_lookup(dnsa, name, type, fully_qualified_name);
137
138time_msec = get_time_in_ms();
139retval = dns_lookup(dnsa, name, type, fully_qualified_name);
140if ((time_msec = get_time_in_ms() - time_msec) > slow_lookup_log)
141 log_long_lookup(US"name", name, time_msec);
142return retval;
143}
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144
145
146/*************************************************
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147* Replace gethostbyname() when testing *
148*************************************************/
149
150/* This function is called instead of gethostbyname(), gethostbyname2(), or
1fb7660f 151getipnodebyname() when running in the test harness. . It also
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152recognizes an unqualified "localhost" and forces it to the appropriate loopback
153address. IP addresses are treated as literals. For other names, it uses the DNS
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154to find the host name. In the test harness, this means it will access only the
155fake DNS resolver.
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156
157Arguments:
158 name the host name or a textual IP address
159 af AF_INET or AF_INET6
160 error_num where to put an error code:
161 HOST_NOT_FOUND/TRY_AGAIN/NO_RECOVERY/NO_DATA
162
163Returns: a hostent structure or NULL for an error
164*/
165
166static struct hostent *
55414b25 167host_fake_gethostbyname(const uschar *name, int af, int *error_num)
e7726cbf 168{
70d67ad3 169#if HAVE_IPV6
e7726cbf 170int alen = (af == AF_INET)? sizeof(struct in_addr):sizeof(struct in6_addr);
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171#else
172int alen = sizeof(struct in_addr);
173#endif
174
175int ipa;
55414b25 176const uschar *lname = name;
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177uschar *adds;
178uschar **alist;
179struct hostent *yield;
180dns_answer dnsa;
181dns_scan dnss;
182dns_record *rr;
183
184DEBUG(D_host_lookup)
185 debug_printf("using host_fake_gethostbyname for %s (%s)\n", name,
186 (af == AF_INET)? "IPv4" : "IPv6");
187
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188/* Handle unqualified "localhost" */
189
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190if (Ustrcmp(name, "localhost") == 0)
191 lname = (af == AF_INET)? US"127.0.0.1" : US"::1";
192
193/* Handle a literal IP address */
194
195ipa = string_is_ip_address(lname, NULL);
196if (ipa != 0)
197 {
198 if ((ipa == 4 && af == AF_INET) ||
199 (ipa == 6 && af == AF_INET6))
200 {
201 int i, n;
202 int x[4];
203 yield = store_get(sizeof(struct hostent));
204 alist = store_get(2 * sizeof(char *));
205 adds = store_get(alen);
206 yield->h_name = CS name;
207 yield->h_aliases = NULL;
208 yield->h_addrtype = af;
209 yield->h_length = alen;
210 yield->h_addr_list = CSS alist;
211 *alist++ = adds;
212 n = host_aton(lname, x);
213 for (i = 0; i < n; i++)
214 {
215 int y = x[i];
216 *adds++ = (y >> 24) & 255;
217 *adds++ = (y >> 16) & 255;
218 *adds++ = (y >> 8) & 255;
219 *adds++ = y & 255;
220 }
221 *alist = NULL;
222 }
223
224 /* Wrong kind of literal address */
225
226 else
227 {
228 *error_num = HOST_NOT_FOUND;
229 return NULL;
230 }
231 }
232
233/* Handle a host name */
234
235else
236 {
237 int type = (af == AF_INET)? T_A:T_AAAA;
846430d9 238 int rc = dns_lookup_timerwrap(&dnsa, lname, type, NULL);
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239 int count = 0;
240
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241 lookup_dnssec_authenticated = NULL;
242
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243 switch(rc)
244 {
245 case DNS_SUCCEED: break;
246 case DNS_NOMATCH: *error_num = HOST_NOT_FOUND; return NULL;
247 case DNS_NODATA: *error_num = NO_DATA; return NULL;
248 case DNS_AGAIN: *error_num = TRY_AGAIN; return NULL;
249 default:
250 case DNS_FAIL: *error_num = NO_RECOVERY; return NULL;
251 }
252
253 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
e1a3f32f 254 rr;
e7726cbf 255 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
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256 if (rr->type == type)
257 count++;
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258
259 yield = store_get(sizeof(struct hostent));
96f5fe4c 260 alist = store_get((count + 1) * sizeof(char *));
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261 adds = store_get(count *alen);
262
263 yield->h_name = CS name;
264 yield->h_aliases = NULL;
265 yield->h_addrtype = af;
266 yield->h_length = alen;
267 yield->h_addr_list = CSS alist;
268
269 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
e1a3f32f 270 rr;
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271 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
272 {
273 int i, n;
274 int x[4];
275 dns_address *da;
276 if (rr->type != type) continue;
e1a3f32f 277 if (!(da = dns_address_from_rr(&dnsa, rr))) break;
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278 *alist++ = adds;
279 n = host_aton(da->address, x);
280 for (i = 0; i < n; i++)
281 {
282 int y = x[i];
283 *adds++ = (y >> 24) & 255;
284 *adds++ = (y >> 16) & 255;
285 *adds++ = (y >> 8) & 255;
286 *adds++ = y & 255;
287 }
288 }
289 *alist = NULL;
290 }
291
292return yield;
293}
294
295
296
297/*************************************************
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298* Build chain of host items from list *
299*************************************************/
300
301/* This function builds a chain of host items from a textual list of host
302names. It does not do any lookups. If randomize is true, the chain is build in
303a randomized order. There may be multiple groups of independently randomized
304hosts; they are delimited by a host name consisting of just "+".
305
306Arguments:
307 anchor anchor for the chain
308 list text list
309 randomize TRUE for randomizing
310
311Returns: nothing
312*/
313
314void
55414b25 315host_build_hostlist(host_item **anchor, const uschar *list, BOOL randomize)
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316{
317int sep = 0;
318int fake_mx = MX_NONE; /* This value is actually -1 */
319uschar *name;
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320
321if (list == NULL) return;
322if (randomize) fake_mx--; /* Start at -2 for randomizing */
323
324*anchor = NULL;
325
55414b25 326while ((name = string_nextinlist(&list, &sep, NULL, 0)) != NULL)
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327 {
328 host_item *h;
329
330 if (name[0] == '+' && name[1] == 0) /* "+" delimits a randomized group */
331 { /* ignore if not randomizing */
332 if (randomize) fake_mx--;
333 continue;
334 }
335
336 h = store_get(sizeof(host_item));
55414b25 337 h->name = name;
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338 h->address = NULL;
339 h->port = PORT_NONE;
340 h->mx = fake_mx;
341 h->sort_key = randomize? (-fake_mx)*1000 + random_number(1000) : 0;
342 h->status = hstatus_unknown;
343 h->why = hwhy_unknown;
344 h->last_try = 0;
345
346 if (*anchor == NULL)
347 {
348 h->next = NULL;
349 *anchor = h;
350 }
351 else
352 {
353 host_item *hh = *anchor;
354 if (h->sort_key < hh->sort_key)
355 {
356 h->next = hh;
357 *anchor = h;
358 }
359 else
360 {
361 while (hh->next != NULL && h->sort_key >= (hh->next)->sort_key)
362 hh = hh->next;
363 h->next = hh->next;
364 hh->next = h;
365 }
366 }
367 }
368}
369
370
371
372
373
374/*************************************************
375* Extract port from address string *
376*************************************************/
377
378/* In the spool file, and in the -oMa and -oMi options, a host plus port is
379given as an IP address followed by a dot and a port number. This function
380decodes this.
381
382An alternative format for the -oMa and -oMi options is [ip address]:port which
383is what Exim 4 uses for output, because it seems to becoming commonly used,
384whereas the dot form confuses some programs/people. So we recognize that form
385too.
386
387Argument:
388 address points to the string; if there is a port, the '.' in the string
389 is overwritten with zero to terminate the address; if the string
390 is in the [xxx]:ppp format, the address is shifted left and the
391 brackets are removed
392
393Returns: 0 if there is no port, else the port number. If there's a syntax
394 error, leave the incoming address alone, and return 0.
395*/
396
397int
7cd1141b 398host_address_extract_port(uschar *address)
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399{
400int port = 0;
401uschar *endptr;
402
403/* Handle the "bracketed with colon on the end" format */
404
405if (*address == '[')
406 {
407 uschar *rb = address + 1;
408 while (*rb != 0 && *rb != ']') rb++;
409 if (*rb++ == 0) return 0; /* Missing ]; leave invalid address */
410 if (*rb == ':')
411 {
412 port = Ustrtol(rb + 1, &endptr, 10);
413 if (*endptr != 0) return 0; /* Invalid port; leave invalid address */
414 }
415 else if (*rb != 0) return 0; /* Bad syntax; leave invalid address */
416 memmove(address, address + 1, rb - address - 2);
417 rb[-2] = 0;
418 }
419
420/* Handle the "dot on the end" format */
421
422else
423 {
424 int skip = -3; /* Skip 3 dots in IPv4 addresses */
425 address--;
426 while (*(++address) != 0)
427 {
428 int ch = *address;
429 if (ch == ':') skip = 0; /* Skip 0 dots in IPv6 addresses */
430 else if (ch == '.' && skip++ >= 0) break;
431 }
432 if (*address == 0) return 0;
433 port = Ustrtol(address + 1, &endptr, 10);
434 if (*endptr != 0) return 0; /* Invalid port; leave invalid address */
435 *address = 0;
436 }
437
438return port;
439}
440
441
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442/*************************************************
443* Get port from a host item's name *
444*************************************************/
445
446/* This function is called when finding the IP address for a host that is in a
447list of hosts explicitly configured, such as in the manualroute router, or in a
448fallback hosts list. We see if there is a port specification at the end of the
449host name, and if so, remove it. A minimum length of 3 is required for the
450original name; nothing shorter is recognized as having a port.
451
452We test for a name ending with a sequence of digits; if preceded by colon we
453have a port if the character before the colon is ] and the name starts with [
454or if there are no other colons in the name (i.e. it's not an IPv6 address).
455
456Arguments: pointer to the host item
457Returns: a port number or PORT_NONE
458*/
459
460int
461host_item_get_port(host_item *h)
462{
55414b25 463const uschar *p;
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464int port, x;
465int len = Ustrlen(h->name);
466
467if (len < 3 || (p = h->name + len - 1, !isdigit(*p))) return PORT_NONE;
468
469/* Extract potential port number */
470
471port = *p-- - '0';
472x = 10;
473
474while (p > h->name + 1 && isdigit(*p))
475 {
476 port += (*p-- - '0') * x;
477 x *= 10;
478 }
479
480/* The smallest value of p at this point is h->name + 1. */
481
482if (*p != ':') return PORT_NONE;
483
484if (p[-1] == ']' && h->name[0] == '[')
485 h->name = string_copyn(h->name + 1, p - h->name - 2);
486else if (Ustrchr(h->name, ':') == p)
487 h->name = string_copyn(h->name, p - h->name);
488else return PORT_NONE;
489
490DEBUG(D_route|D_host_lookup) debug_printf("host=%s port=%d\n", h->name, port);
491return port;
492}
493
494
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495
496#ifndef STAND_ALONE /* Omit when standalone testing */
497
498/*************************************************
499* Build sender_fullhost and sender_rcvhost *
500*************************************************/
501
502/* This function is called when sender_host_name and/or sender_helo_name
503have been set. Or might have been set - for a local message read off the spool
504they won't be. In that case, do nothing. Otherwise, set up the fullhost string
505as follows:
506
507(a) No sender_host_name or sender_helo_name: "[ip address]"
508(b) Just sender_host_name: "host_name [ip address]"
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509(c) Just sender_helo_name: "(helo_name) [ip address]" unless helo is IP
510 in which case: "[ip address}"
511(d) The two are identical: "host_name [ip address]" includes helo = IP
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512(e) The two are different: "host_name (helo_name) [ip address]"
513
514If log_incoming_port is set, the sending host's port number is added to the IP
515address.
516
517This function also builds sender_rcvhost for use in Received: lines, whose
518syntax is a bit different. This value also includes the RFC 1413 identity.
519There wouldn't be two different variables if I had got all this right in the
520first place.
521
522Because this data may survive over more than one incoming SMTP message, it has
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523to be in permanent store. However, STARTTLS has to be forgotten and redone
524on a multi-message conn, so this will be called once per message then. Hence
525we use malloc, so we can free.
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526
527Arguments: none
528Returns: nothing
529*/
530
531void
532host_build_sender_fullhost(void)
533{
82c19f95 534BOOL show_helo = TRUE;
a5c60e3c 535uschar * address, * fullhost, * rcvhost, * reset_point;
82c19f95 536int len;
059ec3d9 537
2d0dc929 538if (!sender_host_address) return;
059ec3d9 539
a5c60e3c 540reset_point = store_get(0);
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541
542/* Set up address, with or without the port. After discussion, it seems that
543the only format that doesn't cause trouble is [aaaa]:pppp. However, we can't
544use this directly as the first item for Received: because it ain't an RFC 2822
545domain. Sigh. */
546
547address = string_sprintf("[%s]:%d", sender_host_address, sender_host_port);
6c6d6e48 548if (!LOGGING(incoming_port) || sender_host_port <= 0)
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549 *(Ustrrchr(address, ':')) = 0;
550
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551/* If there's no EHLO/HELO data, we can't show it. */
552
2d0dc929 553if (!sender_helo_name) show_helo = FALSE;
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554
555/* If HELO/EHLO was followed by an IP literal, it's messy because of two
556features of IPv6. Firstly, there's the "IPv6:" prefix (Exim is liberal and
557doesn't require this, for historical reasons). Secondly, IPv6 addresses may not
4c04137d 558be given in canonical form, so we have to canonicalize them before comparing. As
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559it happens, the code works for both IPv4 and IPv6. */
560
561else if (sender_helo_name[0] == '[' &&
562 sender_helo_name[(len=Ustrlen(sender_helo_name))-1] == ']')
563 {
564 int offset = 1;
565 uschar *helo_ip;
566
567 if (strncmpic(sender_helo_name + 1, US"IPv6:", 5) == 0) offset += 5;
568 if (strncmpic(sender_helo_name + 1, US"IPv4:", 5) == 0) offset += 5;
569
570 helo_ip = string_copyn(sender_helo_name + offset, len - offset - 1);
571
572 if (string_is_ip_address(helo_ip, NULL) != 0)
573 {
574 int x[4], y[4];
575 int sizex, sizey;
576 uschar ipx[48], ipy[48]; /* large enough for full IPv6 */
577
578 sizex = host_aton(helo_ip, x);
579 sizey = host_aton(sender_host_address, y);
580
581 (void)host_nmtoa(sizex, x, -1, ipx, ':');
582 (void)host_nmtoa(sizey, y, -1, ipy, ':');
583
584 if (strcmpic(ipx, ipy) == 0) show_helo = FALSE;
585 }
586 }
587
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588/* Host name is not verified */
589
acec9514 590if (!sender_host_name)
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591 {
592 uschar *portptr = Ustrstr(address, "]:");
acec9514 593 gstring * g;
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594 int adlen; /* Sun compiler doesn't like ++ in initializers */
595
acec9514 596 adlen = portptr ? (++portptr - address) : Ustrlen(address);
a5c60e3c 597 fullhost = sender_helo_name
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598 ? string_sprintf("(%s) %s", sender_helo_name, address)
599 : address;
059ec3d9 600
acec9514 601 g = string_catn(NULL, address, adlen);
059ec3d9 602
2d0dc929 603 if (sender_ident || show_helo || portptr)
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604 {
605 int firstptr;
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606 g = string_catn(g, US" (", 2);
607 firstptr = g->ptr;
059ec3d9 608
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609 if (portptr)
610 g = string_append(g, 2, US"port=", portptr + 1);
059ec3d9 611
82c19f95 612 if (show_helo)
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613 g = string_append(g, 2,
614 firstptr == g->ptr ? US"helo=" : US" helo=", sender_helo_name);
059ec3d9 615
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616 if (sender_ident)
617 g = string_append(g, 2,
618 firstptr == g->ptr ? US"ident=" : US" ident=", sender_ident);
059ec3d9 619
acec9514 620 g = string_catn(g, US")", 1);
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621 }
622
a5c60e3c 623 rcvhost = string_from_gstring(g);
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624 }
625
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626/* Host name is known and verified. Unless we've already found that the HELO
627data matches the IP address, compare it with the name. */
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628
629else
630 {
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631 if (show_helo && strcmpic(sender_host_name, sender_helo_name) == 0)
632 show_helo = FALSE;
5dd9625b 633
82c19f95 634 if (show_helo)
059ec3d9 635 {
a5c60e3c 636 fullhost = string_sprintf("%s (%s) %s", sender_host_name,
059ec3d9 637 sender_helo_name, address);
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638 rcvhost = sender_ident
639 ? string_sprintf("%s\n\t(%s helo=%s ident=%s)", sender_host_name,
640 address, sender_helo_name, sender_ident)
641 : string_sprintf("%s (%s helo=%s)", sender_host_name,
642 address, sender_helo_name);
059ec3d9 643 }
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644 else
645 {
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646 fullhost = string_sprintf("%s %s", sender_host_name, address);
647 rcvhost = sender_ident
648 ? string_sprintf("%s (%s ident=%s)", sender_host_name, address,
649 sender_ident)
650 : string_sprintf("%s (%s)", sender_host_name, address);
82c19f95 651 }
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652 }
653
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654if (sender_fullhost) store_free(sender_fullhost);
655sender_fullhost = string_copy_malloc(fullhost);
656if (sender_rcvhost) store_free(sender_rcvhost);
657sender_rcvhost = string_copy_malloc(rcvhost);
658
659store_reset(reset_point);
059ec3d9
PH
660
661DEBUG(D_host_lookup) debug_printf("sender_fullhost = %s\n", sender_fullhost);
662DEBUG(D_host_lookup) debug_printf("sender_rcvhost = %s\n", sender_rcvhost);
663}
664
665
666
667/*************************************************
668* Build host+ident message *
669*************************************************/
670
671/* Used when logging rejections and various ACL and SMTP incidents. The text
672return depends on whether sender_fullhost and sender_ident are set or not:
673
674 no ident, no host => U=unknown
675 no ident, host set => H=sender_fullhost
676 ident set, no host => U=ident
677 ident set, host set => H=sender_fullhost U=ident
678
679Arguments:
680 useflag TRUE if first item to be flagged (H= or U=); if there are two
681 items, the second is always flagged
682
683Returns: pointer to a string in big_buffer
684*/
685
686uschar *
687host_and_ident(BOOL useflag)
688{
689if (sender_fullhost == NULL)
690 {
691 (void)string_format(big_buffer, big_buffer_size, "%s%s", useflag? "U=" : "",
692 (sender_ident == NULL)? US"unknown" : sender_ident);
693 }
694else
695 {
696 uschar *flag = useflag? US"H=" : US"";
697 uschar *iface = US"";
6c6d6e48 698 if (LOGGING(incoming_interface) && interface_address != NULL)
059ec3d9
PH
699 iface = string_sprintf(" I=[%s]:%d", interface_address, interface_port);
700 if (sender_ident == NULL)
701 (void)string_format(big_buffer, big_buffer_size, "%s%s%s",
702 flag, sender_fullhost, iface);
703 else
704 (void)string_format(big_buffer, big_buffer_size, "%s%s%s U=%s",
705 flag, sender_fullhost, iface, sender_ident);
706 }
707return big_buffer;
708}
709
710#endif /* STAND_ALONE */
711
712
713
714
715/*************************************************
716* Build list of local interfaces *
717*************************************************/
718
719/* This function interprets the contents of the local_interfaces or
720extra_local_interfaces options, and creates an ip_address_item block for each
721item on the list. There is no special interpretation of any IP addresses; in
722particular, 0.0.0.0 and ::0 are returned without modification. If any address
723includes a port, it is set in the block. Otherwise the port value is set to
724zero.
725
726Arguments:
727 list the list
728 name the name of the option being expanded
729
730Returns: a chain of ip_address_items, each containing to a textual
731 version of an IP address, and a port number (host order) or
732 zero if no port was given with the address
733*/
734
735ip_address_item *
55414b25 736host_build_ifacelist(const uschar *list, uschar *name)
059ec3d9
PH
737{
738int sep = 0;
739uschar *s;
b891534f 740ip_address_item * yield = NULL, * last = NULL, * next;
059ec3d9 741
b891534f 742while ((s = string_nextinlist(&list, &sep, NULL, 0)))
059ec3d9 743 {
7e66e54d 744 int ipv;
7cd1141b 745 int port = host_address_extract_port(s); /* Leaves just the IP address */
b891534f
JH
746
747 if (!(ipv = string_is_ip_address(s, NULL)))
059ec3d9
PH
748 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Malformed IP address \"%s\" in %s",
749 s, name);
750
7e66e54d
PH
751 /* Skip IPv6 addresses if IPv6 is disabled. */
752
753 if (disable_ipv6 && ipv == 6) continue;
754
059ec3d9
PH
755 /* This use of strcpy() is OK because we have checked that s is a valid IP
756 address above. The field in the ip_address_item is large enough to hold an
757 IPv6 address. */
758
759 next = store_get(sizeof(ip_address_item));
760 next->next = NULL;
761 Ustrcpy(next->address, s);
762 next->port = port;
763 next->v6_include_v4 = FALSE;
764
b891534f
JH
765 if (!yield)
766 yield = last = next;
767 else
059ec3d9
PH
768 {
769 last->next = next;
770 last = next;
771 }
772 }
773
774return yield;
775}
776
777
778
779
780
781/*************************************************
782* Find addresses on local interfaces *
783*************************************************/
784
785/* This function finds the addresses of local IP interfaces. These are used
786when testing for routing to the local host. As the function may be called more
787than once, the list is preserved in permanent store, pointed to by a static
788variable, to save doing the work more than once per process.
789
790The generic list of interfaces is obtained by calling host_build_ifacelist()
791for local_interfaces and extra_local_interfaces. This list scanned to remove
792duplicates (which may exist with different ports - not relevant here). If
793either of the wildcard IP addresses (0.0.0.0 and ::0) are encountered, they are
794replaced by the appropriate (IPv4 or IPv6) list of actual local interfaces,
795obtained from os_find_running_interfaces().
796
797Arguments: none
798Returns: a chain of ip_address_items, each containing to a textual
799 version of an IP address; the port numbers are not relevant
800*/
801
802
803/* First, a local subfunction to add an interface to a list in permanent store,
804but only if there isn't a previous copy of that address on the list. */
805
806static ip_address_item *
807add_unique_interface(ip_address_item *list, ip_address_item *ipa)
808{
809ip_address_item *ipa2;
810for (ipa2 = list; ipa2 != NULL; ipa2 = ipa2->next)
811 if (Ustrcmp(ipa2->address, ipa->address) == 0) return list;
812ipa2 = store_get_perm(sizeof(ip_address_item));
813*ipa2 = *ipa;
814ipa2->next = list;
815return ipa2;
816}
817
818
819/* This is the globally visible function */
820
821ip_address_item *
822host_find_interfaces(void)
823{
824ip_address_item *running_interfaces = NULL;
825
826if (local_interface_data == NULL)
827 {
828 void *reset_item = store_get(0);
55414b25 829 ip_address_item *dlist = host_build_ifacelist(CUS local_interfaces,
059ec3d9 830 US"local_interfaces");
55414b25 831 ip_address_item *xlist = host_build_ifacelist(CUS extra_local_interfaces,
059ec3d9
PH
832 US"extra_local_interfaces");
833 ip_address_item *ipa;
834
835 if (dlist == NULL) dlist = xlist; else
836 {
837 for (ipa = dlist; ipa->next != NULL; ipa = ipa->next);
838 ipa->next = xlist;
839 }
840
841 for (ipa = dlist; ipa != NULL; ipa = ipa->next)
842 {
843 if (Ustrcmp(ipa->address, "0.0.0.0") == 0 ||
844 Ustrcmp(ipa->address, "::0") == 0)
845 {
846 ip_address_item *ipa2;
847 BOOL ipv6 = ipa->address[0] == ':';
848 if (running_interfaces == NULL)
849 running_interfaces = os_find_running_interfaces();
850 for (ipa2 = running_interfaces; ipa2 != NULL; ipa2 = ipa2->next)
851 {
852 if ((Ustrchr(ipa2->address, ':') != NULL) == ipv6)
853 local_interface_data = add_unique_interface(local_interface_data,
854 ipa2);
855 }
856 }
857 else
858 {
859 local_interface_data = add_unique_interface(local_interface_data, ipa);
860 DEBUG(D_interface)
861 {
862 debug_printf("Configured local interface: address=%s", ipa->address);
863 if (ipa->port != 0) debug_printf(" port=%d", ipa->port);
864 debug_printf("\n");
865 }
866 }
867 }
868 store_reset(reset_item);
869 }
870
871return local_interface_data;
872}
873
874
875
876
877
878/*************************************************
879* Convert network IP address to text *
880*************************************************/
881
882/* Given an IPv4 or IPv6 address in binary, convert it to a text
883string and return the result in a piece of new store. The address can
884either be given directly, or passed over in a sockaddr structure. Note
885that this isn't the converse of host_aton() because of byte ordering
886differences. See host_nmtoa() below.
887
888Arguments:
889 type if < 0 then arg points to a sockaddr, else
890 either AF_INET or AF_INET6
891 arg points to a sockaddr if type is < 0, or
892 points to an IPv4 address (32 bits), or
893 points to an IPv6 address (128 bits),
894 in both cases, in network byte order
895 buffer if NULL, the result is returned in gotten store;
896 else points to a buffer to hold the answer
897 portptr points to where to put the port number, if non NULL; only
898 used when type < 0
899
900Returns: pointer to character string
901*/
902
903uschar *
904host_ntoa(int type, const void *arg, uschar *buffer, int *portptr)
905{
906uschar *yield;
907
908/* The new world. It is annoying that we have to fish out the address from
909different places in the block, depending on what kind of address it is. It
910is also a pain that inet_ntop() returns a const uschar *, whereas the IPv4
911function inet_ntoa() returns just uschar *, and some picky compilers insist
912on warning if one assigns a const uschar * to a uschar *. Hence the casts. */
913
914#if HAVE_IPV6
915uschar addr_buffer[46];
916if (type < 0)
917 {
918 int family = ((struct sockaddr *)arg)->sa_family;
919 if (family == AF_INET6)
920 {
921 struct sockaddr_in6 *sk = (struct sockaddr_in6 *)arg;
5903c6ff 922 yield = US inet_ntop(family, &(sk->sin6_addr), CS addr_buffer,
059ec3d9
PH
923 sizeof(addr_buffer));
924 if (portptr != NULL) *portptr = ntohs(sk->sin6_port);
925 }
926 else
927 {
928 struct sockaddr_in *sk = (struct sockaddr_in *)arg;
5903c6ff 929 yield = US inet_ntop(family, &(sk->sin_addr), CS addr_buffer,
059ec3d9
PH
930 sizeof(addr_buffer));
931 if (portptr != NULL) *portptr = ntohs(sk->sin_port);
932 }
933 }
934else
935 {
5903c6ff 936 yield = US inet_ntop(type, arg, CS addr_buffer, sizeof(addr_buffer));
059ec3d9
PH
937 }
938
939/* If the result is a mapped IPv4 address, show it in V4 format. */
940
941if (Ustrncmp(yield, "::ffff:", 7) == 0) yield += 7;
942
943#else /* HAVE_IPV6 */
944
945/* The old world */
946
947if (type < 0)
948 {
949 yield = US inet_ntoa(((struct sockaddr_in *)arg)->sin_addr);
950 if (portptr != NULL) *portptr = ntohs(((struct sockaddr_in *)arg)->sin_port);
951 }
952else
953 yield = US inet_ntoa(*((struct in_addr *)arg));
954#endif
955
956/* If there is no buffer, put the string into some new store. */
957
958if (buffer == NULL) return string_copy(yield);
959
960/* Callers of this function with a non-NULL buffer must ensure that it is
961large enough to hold an IPv6 address, namely, at least 46 bytes. That's what
962makes this use of strcpy() OK. */
963
964Ustrcpy(buffer, yield);
965return buffer;
966}
967
968
969
970
971/*************************************************
972* Convert address text to binary *
973*************************************************/
974
975/* Given the textual form of an IP address, convert it to binary in an
976array of ints. IPv4 addresses occupy one int; IPv6 addresses occupy 4 ints.
977The result has the first byte in the most significant byte of the first int. In
978other words, the result is not in network byte order, but in host byte order.
979As a result, this is not the converse of host_ntoa(), which expects network
980byte order. See host_nmtoa() below.
981
982Arguments:
983 address points to the textual address, checked for syntax
984 bin points to an array of 4 ints
985
986Returns: the number of ints used
987*/
988
989int
55414b25 990host_aton(const uschar *address, int *bin)
059ec3d9
PH
991{
992int x[4];
993int v4offset = 0;
994
8e669ac1 995/* Handle IPv6 address, which may end with an IPv4 address. It may also end
7e634d24
PH
996with a "scope", introduced by a percent sign. This code is NOT enclosed in #if
997HAVE_IPV6 in order that IPv6 addresses are recognized even if IPv6 is not
998supported. */
059ec3d9
PH
999
1000if (Ustrchr(address, ':') != NULL)
1001 {
55414b25
JH
1002 const uschar *p = address;
1003 const uschar *component[8];
059ec3d9
PH
1004 BOOL ipv4_ends = FALSE;
1005 int ci = 0;
1006 int nulloffset = 0;
1007 int v6count = 8;
1008 int i;
1009
1010 /* If the address starts with a colon, it will start with two colons.
1011 Just lose the first one, which will leave a null first component. */
8e669ac1 1012
059ec3d9
PH
1013 if (*p == ':') p++;
1014
8e669ac1
PH
1015 /* Split the address into components separated by colons. The input address
1016 is supposed to be checked for syntax. There was a case where this was
1017 overlooked; to guard against that happening again, check here and crash if
7e634d24 1018 there are too many components. */
059ec3d9 1019
7e634d24 1020 while (*p != 0 && *p != '%')
059ec3d9 1021 {
7e634d24 1022 int len = Ustrcspn(p, ":%");
059ec3d9 1023 if (len == 0) nulloffset = ci;
8e669ac1 1024 if (ci > 7) log_write(0, LOG_MAIN|LOG_PANIC_DIE,
b975ba52 1025 "Internal error: invalid IPv6 address \"%s\" passed to host_aton()",
8e669ac1 1026 address);
059ec3d9
PH
1027 component[ci++] = p;
1028 p += len;
1029 if (*p == ':') p++;
1030 }
1031
1032 /* If the final component contains a dot, it is a trailing v4 address.
1033 As the syntax is known to be checked, just set up for a trailing
1034 v4 address and restrict the v6 part to 6 components. */
1035
1036 if (Ustrchr(component[ci-1], '.') != NULL)
1037 {
1038 address = component[--ci];
1039 ipv4_ends = TRUE;
1040 v4offset = 3;
1041 v6count = 6;
1042 }
1043
1044 /* If there are fewer than 6 or 8 components, we have to insert some
1045 more empty ones in the middle. */
1046
1047 if (ci < v6count)
1048 {
1049 int insert_count = v6count - ci;
1050 for (i = v6count-1; i > nulloffset + insert_count; i--)
1051 component[i] = component[i - insert_count];
1052 while (i > nulloffset) component[i--] = US"";
1053 }
1054
1055 /* Now turn the components into binary in pairs and bung them
1056 into the vector of ints. */
1057
1058 for (i = 0; i < v6count; i += 2)
1059 bin[i/2] = (Ustrtol(component[i], NULL, 16) << 16) +
1060 Ustrtol(component[i+1], NULL, 16);
1061
1062 /* If there was no terminating v4 component, we are done. */
1063
1064 if (!ipv4_ends) return 4;
1065 }
1066
1067/* Handle IPv4 address */
1068
ff790e47 1069(void)sscanf(CS address, "%d.%d.%d.%d", x, x+1, x+2, x+3);
13559da6 1070bin[v4offset] = ((uint)x[0] << 24) + (x[1] << 16) + (x[2] << 8) + x[3];
059ec3d9
PH
1071return v4offset+1;
1072}
1073
1074
1075/*************************************************
1076* Apply mask to an IP address *
1077*************************************************/
1078
1079/* Mask an address held in 1 or 4 ints, with the ms bit in the ms bit of the
1080first int, etc.
1081
1082Arguments:
1083 count the number of ints
1084 binary points to the ints to be masked
1085 mask the count of ms bits to leave, or -1 if no masking
1086
1087Returns: nothing
1088*/
1089
1090void
1091host_mask(int count, int *binary, int mask)
1092{
1093int i;
1094if (mask < 0) mask = 99999;
1095for (i = 0; i < count; i++)
1096 {
1097 int wordmask;
1098 if (mask == 0) wordmask = 0;
1099 else if (mask < 32)
1100 {
13559da6 1101 wordmask = (uint)(-1) << (32 - mask);
059ec3d9
PH
1102 mask = 0;
1103 }
1104 else
1105 {
1106 wordmask = -1;
1107 mask -= 32;
1108 }
1109 binary[i] &= wordmask;
1110 }
1111}
1112
1113
1114
1115
1116/*************************************************
1117* Convert masked IP address in ints to text *
1118*************************************************/
1119
1120/* We can't use host_ntoa() because it assumes the binary values are in network
1121byte order, and these are the result of host_aton(), which puts them in ints in
1122host byte order. Also, we really want IPv6 addresses to be in a canonical
6f0c9a4f
PH
1123format, so we output them with no abbreviation. In a number of cases we can't
1124use the normal colon separator in them because it terminates keys in lsearch
8e669ac1 1125files, so we want to use dot instead. There's an argument that specifies what
6f0c9a4f 1126to use for IPv6 addresses.
059ec3d9
PH
1127
1128Arguments:
1129 count 1 or 4 (number of ints)
1130 binary points to the ints
1131 mask mask value; if < 0 don't add to result
1132 buffer big enough to hold the result
8e669ac1 1133 sep component separator character for IPv6 addresses
059ec3d9
PH
1134
1135Returns: the number of characters placed in buffer, not counting
1136 the final nul.
1137*/
1138
1139int
6f0c9a4f 1140host_nmtoa(int count, int *binary, int mask, uschar *buffer, int sep)
059ec3d9
PH
1141{
1142int i, j;
1143uschar *tt = buffer;
1144
1145if (count == 1)
1146 {
1147 j = binary[0];
1148 for (i = 24; i >= 0; i -= 8)
fc4a7f70 1149 tt += sprintf(CS tt, "%d.", (j >> i) & 255);
059ec3d9
PH
1150 }
1151else
059ec3d9
PH
1152 for (i = 0; i < 4; i++)
1153 {
1154 j = binary[i];
fc4a7f70 1155 tt += sprintf(CS tt, "%04x%c%04x%c", (j >> 16) & 0xffff, sep, j & 0xffff, sep);
059ec3d9 1156 }
059ec3d9 1157
6f0c9a4f 1158tt--; /* lose final separator */
059ec3d9
PH
1159
1160if (mask < 0)
1161 *tt = 0;
1162else
5976eb99 1163 tt += sprintf(CS tt, "/%d", mask);
059ec3d9
PH
1164
1165return tt - buffer;
1166}
1167
1168
fc4a7f70
JH
1169/* Like host_nmtoa() but: ipv6-only, canonical output, no mask
1170
1171Arguments:
1172 binary points to the ints
1173 buffer big enough to hold the result
1174
1175Returns: the number of characters placed in buffer, not counting
1176 the final nul.
1177*/
1178
1179int
1180ipv6_nmtoa(int * binary, uschar * buffer)
1181{
1182int i, j, k;
1183uschar * c = buffer;
39755c16 1184uschar * d = NULL; /* shut insufficiently "clever" compiler up */
fc4a7f70
JH
1185
1186for (i = 0; i < 4; i++)
1187 { /* expand to text */
1188 j = binary[i];
1189 c += sprintf(CS c, "%x:%x:", (j >> 16) & 0xffff, j & 0xffff);
1190 }
1191
1192for (c = buffer, k = -1, i = 0; i < 8; i++)
1193 { /* find longest 0-group sequence */
1194 if (*c == '0') /* must be "0:" */
1195 {
1196 uschar * s = c;
1197 j = i;
1198 while (c[2] == '0') i++, c += 2;
1199 if (i-j > k)
1200 {
1201 k = i-j; /* length of sequence */
1202 d = s; /* start of sequence */
1203 }
1204 }
1205 while (*++c != ':') ;
1206 c++;
1207 }
1208
1209c[-1] = '\0'; /* drop trailing colon */
1210
1211/* debug_printf("%s: D k %d <%s> <%s>\n", __FUNCTION__, k, d, d + 2*(k+1)); */
1212if (k >= 0)
1213 { /* collapse */
1214 c = d + 2*(k+1);
1215 if (d == buffer) c--; /* need extra colon */
1216 *d++ = ':'; /* 1st 0 */
39755c16 1217 while ((*d++ = *c++)) ;
fc4a7f70
JH
1218 }
1219else
1220 d = c;
1221
1222return d - buffer;
1223}
1224
1225
059ec3d9
PH
1226
1227/*************************************************
1228* Check port for tls_on_connect *
1229*************************************************/
1230
1231/* This function checks whether a given incoming port is configured for tls-
1232on-connect. It is called from the daemon and from inetd handling. If the global
1233option tls_on_connect is already set, all ports operate this way. Otherwise, we
1234check the tls_on_connect_ports option for a list of ports.
1235
1236Argument: a port number
1237Returns: TRUE or FALSE
1238*/
1239
1240BOOL
1241host_is_tls_on_connect_port(int port)
1242{
1243int sep = 0;
1244uschar buffer[32];
55414b25 1245const uschar *list = tls_in.on_connect_ports;
059ec3d9 1246uschar *s;
071c51f7 1247uschar *end;
059ec3d9 1248
817d9f57 1249if (tls_in.on_connect) return TRUE;
059ec3d9 1250
071c51f7
JH
1251while ((s = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))
1252 if (Ustrtol(s, &end, 10) == port)
1253 return TRUE;
059ec3d9
PH
1254
1255return FALSE;
1256}
1257
1258
1259
1260/*************************************************
1261* Check whether host is in a network *
1262*************************************************/
1263
1264/* This function checks whether a given IP address matches a pattern that
1265represents either a single host, or a network (using CIDR notation). The caller
1266of this function must check the syntax of the arguments before calling it.
1267
1268Arguments:
1269 host string representation of the ip-address to check
1270 net string representation of the network, with optional CIDR mask
1271 maskoffset offset to the / that introduces the mask in the key
1272 zero if there is no mask
1273
1274Returns:
1275 TRUE the host is inside the network
1276 FALSE the host is NOT inside the network
1277*/
1278
1279BOOL
55414b25 1280host_is_in_net(const uschar *host, const uschar *net, int maskoffset)
059ec3d9
PH
1281{
1282int i;
1283int address[4];
1284int incoming[4];
1285int mlen;
1286int size = host_aton(net, address);
1287int insize;
1288
1289/* No mask => all bits to be checked */
1290
1291if (maskoffset == 0) mlen = 99999; /* Big number */
1292 else mlen = Uatoi(net + maskoffset + 1);
1293
1294/* Convert the incoming address to binary. */
1295
1296insize = host_aton(host, incoming);
1297
1298/* Convert IPv4 addresses given in IPv6 compatible mode, which represent
1299 connections from IPv4 hosts to IPv6 hosts, that is, addresses of the form
1300 ::ffff:<v4address>, to IPv4 format. */
1301
1302if (insize == 4 && incoming[0] == 0 && incoming[1] == 0 &&
1303 incoming[2] == 0xffff)
1304 {
1305 insize = 1;
1306 incoming[0] = incoming[3];
1307 }
1308
1309/* No match if the sizes don't agree. */
1310
1311if (insize != size) return FALSE;
1312
1313/* Else do the masked comparison. */
1314
1315for (i = 0; i < size; i++)
1316 {
1317 int mask;
1318 if (mlen == 0) mask = 0;
1319 else if (mlen < 32)
1320 {
13559da6 1321 mask = (uint)(-1) << (32 - mlen);
059ec3d9
PH
1322 mlen = 0;
1323 }
1324 else
1325 {
1326 mask = -1;
1327 mlen -= 32;
1328 }
1329 if ((incoming[i] & mask) != (address[i] & mask)) return FALSE;
1330 }
1331
1332return TRUE;
1333}
1334
1335
1336
1337/*************************************************
1338* Scan host list for local hosts *
1339*************************************************/
1340
1341/* Scan through a chain of addresses and check whether any of them is the
1342address of an interface on the local machine. If so, remove that address and
1343any previous ones with the same MX value, and all subsequent ones (which will
1344have greater or equal MX values) from the chain. Note: marking them as unusable
1345is NOT the right thing to do because it causes the hosts not to be used for
1346other domains, for which they may well be correct.
1347
1348The hosts may be part of a longer chain; we only process those between the
1349initial pointer and the "last" pointer.
1350
1351There is also a list of "pseudo-local" host names which are checked against the
1352host names. Any match causes that host item to be treated the same as one which
1353matches a local IP address.
1354
1355If the very first host is a local host, then all MX records had a precedence
1356greater than or equal to that of the local host. Either there's a problem in
1357the DNS, or an apparently remote name turned out to be an abbreviation for the
1358local host. Give a specific return code, and let the caller decide what to do.
1359Otherwise, give a success code if at least one host address has been found.
1360
1361Arguments:
1362 host pointer to the first host in the chain
1363 lastptr pointer to pointer to the last host in the chain (may be updated)
1364 removed if not NULL, set TRUE if some local addresses were removed
1365 from the list
1366
1367Returns:
1368 HOST_FOUND if there is at least one host with an IP address on the chain
1369 and an MX value less than any MX value associated with the
1370 local host
1371 HOST_FOUND_LOCAL if a local host is among the lowest-numbered MX hosts; when
1372 the host addresses were obtained from A records or
1373 gethostbyname(), the MX values are set to -1.
1374 HOST_FIND_FAILED if no valid hosts with set IP addresses were found
1375*/
1376
1377int
1378host_scan_for_local_hosts(host_item *host, host_item **lastptr, BOOL *removed)
1379{
1380int yield = HOST_FIND_FAILED;
1381host_item *last = *lastptr;
1382host_item *prev = NULL;
1383host_item *h;
1384
1385if (removed != NULL) *removed = FALSE;
1386
1387if (local_interface_data == NULL) local_interface_data = host_find_interfaces();
1388
1389for (h = host; h != last->next; h = h->next)
1390 {
1391 #ifndef STAND_ALONE
1392 if (hosts_treat_as_local != NULL)
1393 {
1394 int rc;
55414b25 1395 const uschar *save = deliver_domain;
059ec3d9 1396 deliver_domain = h->name; /* set $domain */
55414b25 1397 rc = match_isinlist(string_copylc(h->name), CUSS &hosts_treat_as_local, 0,
059ec3d9
PH
1398 &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL);
1399 deliver_domain = save;
1400 if (rc == OK) goto FOUND_LOCAL;
1401 }
1402 #endif
1403
1404 /* It seems that on many operating systems, 0.0.0.0 is treated as a synonym
1405 for 127.0.0.1 and refers to the local host. We therefore force it always to
1406 be treated as local. */
1407
1408 if (h->address != NULL)
1409 {
1410 ip_address_item *ip;
1411 if (Ustrcmp(h->address, "0.0.0.0") == 0) goto FOUND_LOCAL;
1412 for (ip = local_interface_data; ip != NULL; ip = ip->next)
1413 if (Ustrcmp(h->address, ip->address) == 0) goto FOUND_LOCAL;
1414 yield = HOST_FOUND; /* At least one remote address has been found */
1415 }
1416
1417 /* Update prev to point to the last host item before any that have
1418 the same MX value as the one we have just considered. */
1419
1420 if (h->next == NULL || h->next->mx != h->mx) prev = h;
1421 }
1422
1423return yield; /* No local hosts found: return HOST_FOUND or HOST_FIND_FAILED */
1424
1425/* A host whose IP address matches a local IP address, or whose name matches
1426something in hosts_treat_as_local has been found. */
1427
1428FOUND_LOCAL:
1429
1430if (prev == NULL)
1431 {
1432 HDEBUG(D_host_lookup) debug_printf((h->mx >= 0)?
1433 "local host has lowest MX\n" :
1434 "local host found for non-MX address\n");
1435 return HOST_FOUND_LOCAL;
1436 }
1437
1438HDEBUG(D_host_lookup)
1439 {
1440 debug_printf("local host in host list - removed hosts:\n");
1441 for (h = prev->next; h != last->next; h = h->next)
1442 debug_printf(" %s %s %d\n", h->name, h->address, h->mx);
1443 }
1444
1445if (removed != NULL) *removed = TRUE;
1446prev->next = last->next;
1447*lastptr = prev;
1448return yield;
1449}
1450
1451
1452
1453
1454/*************************************************
1455* Remove duplicate IPs in host list *
1456*************************************************/
1457
1458/* You would think that administrators could set up their DNS records so that
1459one ended up with a list of unique IP addresses after looking up A or MX
1460records, but apparently duplication is common. So we scan such lists and
1461remove the later duplicates. Note that we may get lists in which some host
1462addresses are not set.
1463
1464Arguments:
1465 host pointer to the first host in the chain
1466 lastptr pointer to pointer to the last host in the chain (may be updated)
1467
1468Returns: nothing
1469*/
1470
1471static void
1472host_remove_duplicates(host_item *host, host_item **lastptr)
1473{
1474while (host != *lastptr)
1475 {
1476 if (host->address != NULL)
1477 {
1478 host_item *h = host;
1479 while (h != *lastptr)
1480 {
1481 if (h->next->address != NULL &&
1482 Ustrcmp(h->next->address, host->address) == 0)
1483 {
1484 DEBUG(D_host_lookup) debug_printf("duplicate IP address %s (MX=%d) "
1485 "removed\n", host->address, h->next->mx);
1486 if (h->next == *lastptr) *lastptr = h;
1487 h->next = h->next->next;
1488 }
1489 else h = h->next;
1490 }
1491 }
1492 /* If the last item was removed, host may have become == *lastptr */
1493 if (host != *lastptr) host = host->next;
1494 }
1495}
1496
1497
1498
1499
1500/*************************************************
1501* Find sender host name by gethostbyaddr() *
1502*************************************************/
1503
1504/* This used to be the only way it was done, but it turns out that not all
1505systems give aliases for calls to gethostbyaddr() - or one of the modern
1506equivalents like getipnodebyaddr(). Fortunately, multiple PTR records are rare,
1507but they can still exist. This function is now used only when a DNS lookup of
1508the IP address fails, in order to give access to /etc/hosts.
1509
1510Arguments: none
1511Returns: OK, DEFER, FAIL
1512*/
1513
1514static int
1515host_name_lookup_byaddr(void)
1516{
1517int len;
1518uschar *s, *t;
1519struct hostent *hosts;
1520struct in_addr addr;
f2cb6292 1521unsigned long time_msec = 0; /* init to quieten dumb static analysis */
846430d9
JH
1522
1523if (slow_lookup_log) time_msec = get_time_in_ms();
059ec3d9
PH
1524
1525/* Lookup on IPv6 system */
1526
1527#if HAVE_IPV6
1528if (Ustrchr(sender_host_address, ':') != NULL)
1529 {
1530 struct in6_addr addr6;
1531 if (inet_pton(AF_INET6, CS sender_host_address, &addr6) != 1)
1532 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "unable to parse \"%s\" as an "
1533 "IPv6 address", sender_host_address);
1534 #if HAVE_GETIPNODEBYADDR
1535 hosts = getipnodebyaddr(CS &addr6, sizeof(addr6), AF_INET6, &h_errno);
1536 #else
1537 hosts = gethostbyaddr(CS &addr6, sizeof(addr6), AF_INET6);
1538 #endif
1539 }
1540else
1541 {
1542 if (inet_pton(AF_INET, CS sender_host_address, &addr) != 1)
1543 log_write(0, LOG_MAIN|LOG_PANIC_DIE, "unable to parse \"%s\" as an "
1544 "IPv4 address", sender_host_address);
1545 #if HAVE_GETIPNODEBYADDR
1546 hosts = getipnodebyaddr(CS &addr, sizeof(addr), AF_INET, &h_errno);
1547 #else
1548 hosts = gethostbyaddr(CS &addr, sizeof(addr), AF_INET);
1549 #endif
1550 }
1551
1552/* Do lookup on IPv4 system */
1553
1554#else
1555addr.s_addr = (S_ADDR_TYPE)inet_addr(CS sender_host_address);
1556hosts = gethostbyaddr(CS(&addr), sizeof(addr), AF_INET);
1557#endif
1558
846430d9
JH
1559if ( slow_lookup_log
1560 && (time_msec = get_time_in_ms() - time_msec) > slow_lookup_log
1561 )
1562 log_long_lookup(US"name", sender_host_address, time_msec);
1563
059ec3d9
PH
1564/* Failed to look up the host. */
1565
1566if (hosts == NULL)
1567 {
1568 HDEBUG(D_host_lookup) debug_printf("IP address lookup failed: h_errno=%d\n",
1569 h_errno);
1570 return (h_errno == TRY_AGAIN || h_errno == NO_RECOVERY) ? DEFER : FAIL;
1571 }
1572
1573/* It seems there are some records in the DNS that yield an empty name. We
1574treat this as non-existent. In some operating systems, this is returned as an
1575empty string; in others as a single dot. */
1576
8ad076b2 1577if (hosts->h_name == NULL || hosts->h_name[0] == 0 || hosts->h_name[0] == '.')
059ec3d9
PH
1578 {
1579 HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an empty name: "
1580 "treated as non-existent host name\n");
1581 return FAIL;
1582 }
1583
1584/* Copy and lowercase the name, which is in static storage in many systems.
1585Put it in permanent memory. */
1586
5903c6ff 1587s = US hosts->h_name;
059ec3d9
PH
1588len = Ustrlen(s) + 1;
1589t = sender_host_name = store_get_perm(len);
1590while (*s != 0) *t++ = tolower(*s++);
1591*t = 0;
1592
1593/* If the host has aliases, build a copy of the alias list */
1594
1595if (hosts->h_aliases != NULL)
1596 {
1597 int count = 1;
1598 uschar **aliases, **ptr;
1599 for (aliases = USS hosts->h_aliases; *aliases != NULL; aliases++) count++;
1600 ptr = sender_host_aliases = store_get_perm(count * sizeof(uschar *));
1601 for (aliases = USS hosts->h_aliases; *aliases != NULL; aliases++)
1602 {
1603 uschar *s = *aliases;
1604 int len = Ustrlen(s) + 1;
1605 uschar *t = *ptr++ = store_get_perm(len);
1606 while (*s != 0) *t++ = tolower(*s++);
1607 *t = 0;
1608 }
1609 *ptr = NULL;
1610 }
1611
1612return OK;
1613}
1614
1615
1616
1617/*************************************************
1618* Find host name for incoming call *
1619*************************************************/
1620
1621/* Put the name in permanent store, pointed to by sender_host_name. We also set
1622up a list of alias names, pointed to by sender_host_alias. The list is
1623NULL-terminated. The incoming address is in sender_host_address, either in
1624dotted-quad form for IPv4 or in colon-separated form for IPv6.
1625
1626This function does a thorough check that the names it finds point back to the
1627incoming IP address. Any that do not are discarded. Note that this is relied on
1628by the ACL reverse_host_lookup check.
1629
1630On some systems, get{host,ipnode}byaddr() appears to do this internally, but
1631this it not universally true. Also, for release 4.30, this function was changed
1632to do a direct DNS lookup first, by default[1], because it turns out that that
1633is the only guaranteed way to find all the aliases on some systems. My
1634experiments indicate that Solaris gethostbyaddr() gives the aliases for but
1635Linux does not.
1636
1637[1] The actual order is controlled by the host_lookup_order option.
1638
1639Arguments: none
1640Returns: OK on success, the answer being placed in the global variable
1641 sender_host_name, with any aliases in a list hung off
1642 sender_host_aliases
1643 FAIL if no host name can be found
1644 DEFER if a temporary error was encountered
1645
4c04137d 1646The variable host_lookup_msg is set to an empty string on success, or to a
059ec3d9 1647reason for the failure otherwise, in a form suitable for tagging onto an error
8e669ac1 1648message, and also host_lookup_failed is set TRUE if the lookup failed. If there
b08b24c8
PH
1649was a defer, host_lookup_deferred is set TRUE.
1650
1651Any dynamically constructed string for host_lookup_msg must be in permanent
1652store, because it might be used for several incoming messages on the same SMTP
059ec3d9
PH
1653connection. */
1654
1655int
1656host_name_lookup(void)
1657{
1658int old_pool, rc;
1659int sep = 0;
1660uschar *hname, *save_hostname;
1661uschar **aliases;
1662uschar buffer[256];
1663uschar *ordername;
55414b25 1664const uschar *list = host_lookup_order;
059ec3d9
PH
1665dns_record *rr;
1666dns_answer dnsa;
1667dns_scan dnss;
1668
1f4a55da 1669sender_host_dnssec = host_lookup_deferred = host_lookup_failed = FALSE;
b08b24c8 1670
059ec3d9
PH
1671HDEBUG(D_host_lookup)
1672 debug_printf("looking up host name for %s\n", sender_host_address);
1673
1674/* For testing the case when a lookup does not complete, we have a special
1675reserved IP address. */
1676
8768d548 1677if (f.running_in_test_harness &&
059ec3d9
PH
1678 Ustrcmp(sender_host_address, "99.99.99.99") == 0)
1679 {
1680 HDEBUG(D_host_lookup)
1681 debug_printf("Test harness: host name lookup returns DEFER\n");
8e669ac1 1682 host_lookup_deferred = TRUE;
059ec3d9
PH
1683 return DEFER;
1684 }
1685
1686/* Do lookups directly in the DNS or via gethostbyaddr() (or equivalent), in
1687the order specified by the host_lookup_order option. */
1688
1f155f8e 1689while ((ordername = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))
059ec3d9
PH
1690 {
1691 if (strcmpic(ordername, US"bydns") == 0)
1692 {
9d9c3746 1693 dns_init(FALSE, FALSE, FALSE); /* dnssec ctrl by dns_dnssec_ok glbl */
059ec3d9 1694 dns_build_reverse(sender_host_address, buffer);
846430d9 1695 rc = dns_lookup_timerwrap(&dnsa, buffer, T_PTR, NULL);
059ec3d9
PH
1696
1697 /* The first record we come across is used for the name; others are
1698 considered to be aliases. We have to scan twice, in order to find out the
1699 number of aliases. However, if all the names are empty, we will behave as
1700 if failure. (PTR records that yield empty names have been encountered in
1701 the DNS.) */
1702
1703 if (rc == DNS_SUCCEED)
1704 {
1705 uschar **aptr = NULL;
1706 int ssize = 264;
1707 int count = 0;
1708 int old_pool = store_pool;
1709
1f4a55da
PP
1710 sender_host_dnssec = dns_is_secure(&dnsa);
1711 DEBUG(D_dns)
1712 debug_printf("Reverse DNS security status: %s\n",
1713 sender_host_dnssec ? "DNSSEC verified (AD)" : "unverified");
1714
059ec3d9
PH
1715 store_pool = POOL_PERM; /* Save names in permanent storage */
1716
1717 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1705dd20 1718 rr;
059ec3d9 1719 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1705dd20
JH
1720 if (rr->type == T_PTR)
1721 count++;
059ec3d9
PH
1722
1723 /* Get store for the list of aliases. For compatibility with
1724 gethostbyaddr, we make an empty list if there are none. */
1725
1726 aptr = sender_host_aliases = store_get(count * sizeof(uschar *));
1727
1728 /* Re-scan and extract the names */
1729
1730 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
1705dd20 1731 rr;
059ec3d9
PH
1732 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
1733 {
1734 uschar *s = NULL;
1735 if (rr->type != T_PTR) continue;
1736 s = store_get(ssize);
1737
1738 /* If an overlong response was received, the data will have been
1739 truncated and dn_expand may fail. */
1740
1741 if (dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen,
5903c6ff 1742 US (rr->data), (DN_EXPAND_ARG4_TYPE)(s), ssize) < 0)
059ec3d9
PH
1743 {
1744 log_write(0, LOG_MAIN, "host name alias list truncated for %s",
1745 sender_host_address);
1746 break;
1747 }
1748
1749 store_reset(s + Ustrlen(s) + 1);
1750 if (s[0] == 0)
1751 {
1752 HDEBUG(D_host_lookup) debug_printf("IP address lookup yielded an "
1753 "empty name: treated as non-existent host name\n");
1754 continue;
1755 }
1f155f8e
JH
1756 if (!sender_host_name) sender_host_name = s;
1757 else *aptr++ = s;
059ec3d9
PH
1758 while (*s != 0) { *s = tolower(*s); s++; }
1759 }
1760
1761 *aptr = NULL; /* End of alias list */
1762 store_pool = old_pool; /* Reset store pool */
1763
1764 /* If we've found a names, break out of the "order" loop */
1765
1766 if (sender_host_name != NULL) break;
1767 }
1768
1769 /* If the DNS lookup deferred, we must also defer. */
1770
1771 if (rc == DNS_AGAIN)
1772 {
1773 HDEBUG(D_host_lookup)
1774 debug_printf("IP address PTR lookup gave temporary error\n");
8e669ac1 1775 host_lookup_deferred = TRUE;
059ec3d9
PH
1776 return DEFER;
1777 }
1778 }
1779
1780 /* Do a lookup using gethostbyaddr() - or equivalent */
1781
1782 else if (strcmpic(ordername, US"byaddr") == 0)
1783 {
1784 HDEBUG(D_host_lookup)
1785 debug_printf("IP address lookup using gethostbyaddr()\n");
059ec3d9 1786 rc = host_name_lookup_byaddr();
8e669ac1 1787 if (rc == DEFER)
b08b24c8 1788 {
8e669ac1 1789 host_lookup_deferred = TRUE;
b08b24c8 1790 return rc; /* Can't carry on */
8e669ac1 1791 }
059ec3d9
PH
1792 if (rc == OK) break; /* Found a name */
1793 }
1794 } /* Loop for bydns/byaddr scanning */
1795
1796/* If we have failed to find a name, return FAIL and log when required.
1797NB host_lookup_msg must be in permanent store. */
1798
94759fce 1799if (!sender_host_name)
059ec3d9 1800 {
8768d548 1801 if (host_checking || !f.log_testing_mode)
059ec3d9
PH
1802 log_write(L_host_lookup_failed, LOG_MAIN, "no host name found for IP "
1803 "address %s", sender_host_address);
1804 host_lookup_msg = US" (failed to find host name from IP address)";
b08b24c8 1805 host_lookup_failed = TRUE;
059ec3d9
PH
1806 return FAIL;
1807 }
1808
059ec3d9
PH
1809HDEBUG(D_host_lookup)
1810 {
1811 uschar **aliases = sender_host_aliases;
de11307f
JH
1812 debug_printf("IP address lookup yielded \"%s\"\n", sender_host_name);
1813 while (*aliases != NULL) debug_printf(" alias \"%s\"\n", *aliases++);
059ec3d9
PH
1814 }
1815
1816/* We need to verify that a forward lookup on the name we found does indeed
1817correspond to the address. This is for security: in principle a malefactor who
1818happened to own a reverse zone could set it to point to any names at all.
1819
1820This code was present in versions of Exim before 3.20. At that point I took it
1821out because I thought that gethostbyaddr() did the check anyway. It turns out
1822that this isn't always the case, so it's coming back in at 4.01. This version
1823is actually better, because it also checks aliases.
1824
1825The code was made more robust at release 4.21. Prior to that, it accepted all
1826the names if any of them had the correct IP address. Now the code checks all
1827the names, and accepts only those that have the correct IP address. */
1828
1829save_hostname = sender_host_name; /* Save for error messages */
1830aliases = sender_host_aliases;
2546388c 1831for (hname = sender_host_name; hname; hname = *aliases++)
059ec3d9
PH
1832 {
1833 int rc;
1834 BOOL ok = FALSE;
94759fce
JH
1835 host_item h = { .next = NULL, .name = hname, .mx = MX_NONE, .address = NULL };
1836 dnssec_domains d =
1837 { .request = sender_host_dnssec ? US"*" : NULL, .require = NULL };
059ec3d9 1838
66387a73 1839 if ( (rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A | HOST_FIND_BY_AAAA,
1f155f8e
JH
1840 NULL, NULL, NULL, &d, NULL, NULL)) == HOST_FOUND
1841 || rc == HOST_FOUND_LOCAL
1842 )
059ec3d9
PH
1843 {
1844 host_item *hh;
059ec3d9 1845 HDEBUG(D_host_lookup) debug_printf("checking addresses for %s\n", hname);
1f155f8e
JH
1846
1847 /* If the forward lookup was not secure we cancel the is-secure variable */
1848
1849 DEBUG(D_dns) debug_printf("Forward DNS security status: %s\n",
1850 h.dnssec == DS_YES ? "DNSSEC verified (AD)" : "unverified");
1851 if (h.dnssec != DS_YES) sender_host_dnssec = FALSE;
1852
2546388c 1853 for (hh = &h; hh; hh = hh->next)
d27f1df3 1854 if (host_is_in_net(hh->address, sender_host_address, 0))
059ec3d9
PH
1855 {
1856 HDEBUG(D_host_lookup) debug_printf(" %s OK\n", hh->address);
1857 ok = TRUE;
1858 break;
1859 }
1860 else
059ec3d9 1861 HDEBUG(D_host_lookup) debug_printf(" %s\n", hh->address);
1f155f8e 1862
059ec3d9
PH
1863 if (!ok) HDEBUG(D_host_lookup)
1864 debug_printf("no IP address for %s matched %s\n", hname,
1865 sender_host_address);
1866 }
1867 else if (rc == HOST_FIND_AGAIN)
1868 {
1869 HDEBUG(D_host_lookup) debug_printf("temporary error for host name lookup\n");
8e669ac1 1870 host_lookup_deferred = TRUE;
55728a4f 1871 sender_host_name = NULL;
059ec3d9
PH
1872 return DEFER;
1873 }
1874 else
059ec3d9 1875 HDEBUG(D_host_lookup) debug_printf("no IP addresses found for %s\n", hname);
059ec3d9
PH
1876
1877 /* If this name is no good, and it's the sender name, set it null pro tem;
1878 if it's an alias, just remove it from the list. */
1879
1880 if (!ok)
1881 {
1882 if (hname == sender_host_name) sender_host_name = NULL; else
1883 {
1884 uschar **a; /* Don't amalgamate - some */
1885 a = --aliases; /* compilers grumble */
1886 while (*a != NULL) { *a = a[1]; a++; }
1887 }
1888 }
1889 }
1890
1891/* If sender_host_name == NULL, it means we didn't like the name. Replace
1892it with the first alias, if there is one. */
1893
1894if (sender_host_name == NULL && *sender_host_aliases != NULL)
1895 sender_host_name = *sender_host_aliases++;
1896
1897/* If we now have a main name, all is well. */
1898
1899if (sender_host_name != NULL) return OK;
1900
1901/* We have failed to find an address that matches. */
1902
1903HDEBUG(D_host_lookup)
1904 debug_printf("%s does not match any IP address for %s\n",
1905 sender_host_address, save_hostname);
1906
1907/* This message must be in permanent store */
1908
1909old_pool = store_pool;
1910store_pool = POOL_PERM;
1911host_lookup_msg = string_sprintf(" (%s does not match any IP address for %s)",
1912 sender_host_address, save_hostname);
1913store_pool = old_pool;
059ec3d9
PH
1914host_lookup_failed = TRUE;
1915return FAIL;
1916}
1917
1918
1919
1920
1921/*************************************************
1922* Find IP address(es) for host by name *
1923*************************************************/
1924
1925/* The input is a host_item structure with the name filled in and the address
322050c2
PH
1926field set to NULL. We use gethostbyname() or getipnodebyname() or
1927gethostbyname2(), as appropriate. Of course, these functions may use the DNS,
1928but they do not do MX processing. It appears, however, that in some systems the
1929current setting of resolver options is used when one of these functions calls
1930the resolver. For this reason, we call dns_init() at the start, with arguments
1931influenced by bits in "flags", just as we do for host_find_bydns().
059ec3d9
PH
1932
1933The second argument provides a host list (usually an IP list) of hosts to
1934ignore. This makes it possible to ignore IPv6 link-local addresses or loopback
1935addresses in unreasonable places.
1936
1937The lookup may result in a change of name. For compatibility with the dns
1938lookup, return this via fully_qualified_name as well as updating the host item.
1939The lookup may also yield more than one IP address, in which case chain on
1940subsequent host_item structures.
1941
1942Arguments:
1943 host a host item with the name and MX filled in;
1944 the address is to be filled in;
1945 multiple IP addresses cause other host items to be
1946 chained on.
1947 ignore_target_hosts a list of hosts to ignore
322050c2
PH
1948 flags HOST_FIND_QUALIFY_SINGLE ) passed to
1949 HOST_FIND_SEARCH_PARENTS ) dns_init()
059ec3d9
PH
1950 fully_qualified_name if not NULL, set to point to host name for
1951 compatibility with host_find_bydns
1952 local_host_check TRUE if a check for the local host is wanted
1953
1954Returns: HOST_FIND_FAILED Failed to find the host or domain
1955 HOST_FIND_AGAIN Try again later
1956 HOST_FOUND Host found - data filled in
1957 HOST_FOUND_LOCAL Host found and is the local host
1958*/
1959
1960int
55414b25
JH
1961host_find_byname(host_item *host, const uschar *ignore_target_hosts, int flags,
1962 const uschar **fully_qualified_name, BOOL local_host_check)
059ec3d9
PH
1963{
1964int i, yield, times;
1965uschar **addrlist;
1966host_item *last = NULL;
1967BOOL temp_error = FALSE;
b08b24c8
PH
1968#if HAVE_IPV6
1969int af;
1970#endif
1971
322050c2
PH
1972/* Make sure DNS options are set as required. This appears to be necessary in
1973some circumstances when the get..byname() function actually calls the DNS. */
1974
1975dns_init((flags & HOST_FIND_QUALIFY_SINGLE) != 0,
8c51eead 1976 (flags & HOST_FIND_SEARCH_PARENTS) != 0,
7cd171b7 1977 FALSE); /* Cannot retrieve dnssec status so do not request */
322050c2 1978
7e66e54d
PH
1979/* In an IPv6 world, unless IPv6 has been disabled, we need to scan for both
1980kinds of address, so go round the loop twice. Note that we have ensured that
1981AF_INET6 is defined even in an IPv4 world, which makes for slightly tidier
1982code. However, if dns_ipv4_lookup matches the domain, we also just do IPv4
1983lookups here (except when testing standalone). */
059ec3d9
PH
1984
1985#if HAVE_IPV6
322050c2
PH
1986 #ifdef STAND_ALONE
1987 if (disable_ipv6)
1988 #else
1989 if (disable_ipv6 ||
1990 (dns_ipv4_lookup != NULL &&
55414b25
JH
1991 match_isinlist(host->name, CUSS &dns_ipv4_lookup, 0, NULL, NULL,
1992 MCL_DOMAIN, TRUE, NULL) == OK))
322050c2
PH
1993 #endif
1994
059ec3d9
PH
1995 { af = AF_INET; times = 1; }
1996 else
059ec3d9
PH
1997 { af = AF_INET6; times = 2; }
1998
1999/* No IPv6 support */
2000
2001#else /* HAVE_IPV6 */
2002 times = 1;
2003#endif /* HAVE_IPV6 */
2004
2005/* Initialize the flag that gets set for DNS syntax check errors, so that the
2006interface to this function can be similar to host_find_bydns. */
2007
8768d548 2008f.host_find_failed_syntax = FALSE;
059ec3d9
PH
2009
2010/* Loop to look up both kinds of address in an IPv6 world */
2011
2012for (i = 1; i <= times;
2013 #if HAVE_IPV6
2014 af = AF_INET, /* If 2 passes, IPv4 on the second */
2015 #endif
2016 i++)
2017 {
2018 BOOL ipv4_addr;
91ecef39 2019 int error_num = 0;
059ec3d9 2020 struct hostent *hostdata;
0539a19d 2021 unsigned long time_msec = 0; /* compiler quietening */
059ec3d9 2022
322050c2
PH
2023 #ifdef STAND_ALONE
2024 printf("Looking up: %s\n", host->name);
2025 #endif
2026
846430d9
JH
2027 if (slow_lookup_log) time_msec = get_time_in_ms();
2028
059ec3d9 2029 #if HAVE_IPV6
8768d548 2030 if (f.running_in_test_harness)
e7726cbf
PH
2031 hostdata = host_fake_gethostbyname(host->name, af, &error_num);
2032 else
2033 {
059ec3d9
PH
2034 #if HAVE_GETIPNODEBYNAME
2035 hostdata = getipnodebyname(CS host->name, af, 0, &error_num);
2036 #else
2037 hostdata = gethostbyname2(CS host->name, af);
2038 error_num = h_errno;
2039 #endif
e7726cbf
PH
2040 }
2041
2042 #else /* not HAVE_IPV6 */
8768d548 2043 if (f.running_in_test_harness)
e7726cbf
PH
2044 hostdata = host_fake_gethostbyname(host->name, AF_INET, &error_num);
2045 else
2046 {
2047 hostdata = gethostbyname(CS host->name);
2048 error_num = h_errno;
2049 }
2050 #endif /* HAVE_IPV6 */
059ec3d9 2051
0539a19d 2052 if ( slow_lookup_log
abe1353e
HSHR
2053 && (time_msec = get_time_in_ms() - time_msec) > slow_lookup_log)
2054 log_long_lookup(US"name", host->name, time_msec);
846430d9 2055
059ec3d9
PH
2056 if (hostdata == NULL)
2057 {
2058 uschar *error;
2059 switch (error_num)
2060 {
2061 case HOST_NOT_FOUND: error = US"HOST_NOT_FOUND"; break;
4a452c43
JH
2062 case TRY_AGAIN: error = US"TRY_AGAIN"; break;
2063 case NO_RECOVERY: error = US"NO_RECOVERY"; break;
2064 case NO_DATA: error = US"NO_DATA"; break;
059ec3d9 2065 #if NO_DATA != NO_ADDRESS
4a452c43 2066 case NO_ADDRESS: error = US"NO_ADDRESS"; break;
059ec3d9
PH
2067 #endif
2068 default: error = US"?"; break;
2069 }
2070
2071 DEBUG(D_host_lookup) debug_printf("%s returned %d (%s)\n",
2072 #if HAVE_IPV6
2073 #if HAVE_GETIPNODEBYNAME
2074 (af == AF_INET6)? "getipnodebyname(af=inet6)" : "getipnodebyname(af=inet)",
2075 #else
2076 (af == AF_INET6)? "gethostbyname2(af=inet6)" : "gethostbyname2(af=inet)",
2077 #endif
2078 #else
2079 "gethostbyname",
2080 #endif
2081 error_num, error);
2082
2083 if (error_num == TRY_AGAIN || error_num == NO_RECOVERY) temp_error = TRUE;
2084 continue;
2085 }
2086 if ((hostdata->h_addr_list)[0] == NULL) continue;
2087
2088 /* Replace the name with the fully qualified one if necessary, and fill in
2089 the fully_qualified_name pointer. */
2090
2091 if (hostdata->h_name[0] != 0 &&
2092 Ustrcmp(host->name, hostdata->h_name) != 0)
5903c6ff 2093 host->name = string_copy_dnsdomain(US hostdata->h_name);
059ec3d9
PH
2094 if (fully_qualified_name != NULL) *fully_qualified_name = host->name;
2095
2096 /* Get the list of addresses. IPv4 and IPv6 addresses can be distinguished
2097 by their different lengths. Scan the list, ignoring any that are to be
2098 ignored, and build a chain from the rest. */
2099
2100 ipv4_addr = hostdata->h_length == sizeof(struct in_addr);
2101
2102 for (addrlist = USS hostdata->h_addr_list; *addrlist != NULL; addrlist++)
2103 {
2104 uschar *text_address =
2105 host_ntoa(ipv4_addr? AF_INET:AF_INET6, *addrlist, NULL, NULL);
2106
2107 #ifndef STAND_ALONE
2108 if (ignore_target_hosts != NULL &&
2109 verify_check_this_host(&ignore_target_hosts, NULL, host->name,
2110 text_address, NULL) == OK)
2111 {
2112 DEBUG(D_host_lookup)
2113 debug_printf("ignored host %s [%s]\n", host->name, text_address);
2114 continue;
2115 }
2116 #endif
2117
2118 /* If this is the first address, last == NULL and we put the data in the
2119 original block. */
2120
2121 if (last == NULL)
2122 {
2123 host->address = text_address;
2124 host->port = PORT_NONE;
2125 host->status = hstatus_unknown;
2126 host->why = hwhy_unknown;
783b385f 2127 host->dnssec = DS_UNK;
059ec3d9
PH
2128 last = host;
2129 }
2130
2131 /* Else add further host item blocks for any other addresses, keeping
2132 the order. */
2133
2134 else
2135 {
2136 host_item *next = store_get(sizeof(host_item));
2137 next->name = host->name;
2138 next->mx = host->mx;
2139 next->address = text_address;
2140 next->port = PORT_NONE;
2141 next->status = hstatus_unknown;
2142 next->why = hwhy_unknown;
783b385f 2143 next->dnssec = DS_UNK;
059ec3d9
PH
2144 next->last_try = 0;
2145 next->next = last->next;
2146 last->next = next;
2147 last = next;
2148 }
2149 }
2150 }
2151
2152/* If no hosts were found, the address field in the original host block will be
2153NULL. If temp_error is set, at least one of the lookups gave a temporary error,
2154so we pass that back. */
2155
2156if (host->address == NULL)
2157 {
2158 uschar *msg =
2159 #ifndef STAND_ALONE
2160 (message_id[0] == 0 && smtp_in != NULL)?
2161 string_sprintf("no IP address found for host %s (during %s)", host->name,
2162 smtp_get_connection_info()) :
2163 #endif
2164 string_sprintf("no IP address found for host %s", host->name);
2165
2166 HDEBUG(D_host_lookup) debug_printf("%s\n", msg);
9b8fadde 2167 if (temp_error) goto RETURN_AGAIN;
8768d548 2168 if (host_checking || !f.log_testing_mode)
059ec3d9
PH
2169 log_write(L_host_lookup_failed, LOG_MAIN, "%s", msg);
2170 return HOST_FIND_FAILED;
2171 }
2172
2173/* Remove any duplicate IP addresses, then check to see if this is the local
2174host if required. */
2175
2176host_remove_duplicates(host, &last);
2177yield = local_host_check?
2178 host_scan_for_local_hosts(host, &last, NULL) : HOST_FOUND;
2179
059ec3d9
PH
2180HDEBUG(D_host_lookup)
2181 {
55414b25 2182 const host_item *h;
059ec3d9
PH
2183 if (fully_qualified_name != NULL)
2184 debug_printf("fully qualified name = %s\n", *fully_qualified_name);
2185 debug_printf("%s looked up these IP addresses:\n",
2186 #if HAVE_IPV6
2187 #if HAVE_GETIPNODEBYNAME
2188 "getipnodebyname"
2189 #else
2190 "gethostbyname2"
2191 #endif
2192 #else
2193 "gethostbyname"
2194 #endif
2195 );
2196 for (h = host; h != last->next; h = h->next)
2197 debug_printf(" name=%s address=%s\n", h->name,
2198 (h->address == NULL)? US"<null>" : h->address);
2199 }
2200
2201/* Return the found status. */
2202
2203return yield;
9b8fadde
PH
2204
2205/* Handle the case when there is a temporary error. If the name matches
2206dns_again_means_nonexist, return permanent rather than temporary failure. */
2207
2208RETURN_AGAIN:
2209 {
2210 #ifndef STAND_ALONE
2211 int rc;
55414b25 2212 const uschar *save = deliver_domain;
9b8fadde 2213 deliver_domain = host->name; /* set $domain */
55414b25 2214 rc = match_isinlist(host->name, CUSS &dns_again_means_nonexist, 0, NULL, NULL,
9b8fadde
PH
2215 MCL_DOMAIN, TRUE, NULL);
2216 deliver_domain = save;
2217 if (rc == OK)
2218 {
2219 DEBUG(D_host_lookup) debug_printf("%s is in dns_again_means_nonexist: "
2220 "returning HOST_FIND_FAILED\n", host->name);
2221 return HOST_FIND_FAILED;
2222 }
2223 #endif
2224 return HOST_FIND_AGAIN;
2225 }
059ec3d9
PH
2226}
2227
2228
2229
2230/*************************************************
2231* Fill in a host address from the DNS *
2232*************************************************/
2233
1349e1e5
PH
2234/* Given a host item, with its name, port and mx fields set, and its address
2235field set to NULL, fill in its IP address from the DNS. If it is multi-homed,
2236create additional host items for the additional addresses, copying all the
2237other fields, and randomizing the order.
059ec3d9 2238
66387a73 2239On IPv6 systems, AAAA records are sought first, then A records.
059ec3d9
PH
2240
2241The host name may be changed if the DNS returns a different name - e.g. fully
2242qualified or changed via CNAME. If fully_qualified_name is not NULL, dns_lookup
2243ensures that it points to the fully qualified name. However, this is the fully
2244qualified version of the original name; if a CNAME is involved, the actual
2245canonical host name may be different again, and so we get it directly from the
2246relevant RR. Note that we do NOT change the mx field of the host item in this
2247function as it may be called to set the addresses of hosts taken from MX
2248records.
2249
2250Arguments:
2251 host points to the host item we're filling in
2252 lastptr points to pointer to last host item in a chain of
2253 host items (may be updated if host is last and gets
2254 extended because multihomed)
2255 ignore_target_hosts list of hosts to ignore
2256 allow_ip if TRUE, recognize an IP address and return it
2257 fully_qualified_name if not NULL, return fully qualified name here if
2258 the contents are different (i.e. it must be preset
2259 to something)
221dff13
HSHR
2260 dnssec_request if TRUE request the AD bit
2261 dnssec_require if TRUE require the AD bit
66387a73 2262 whichrrs select ipv4, ipv6 results
059ec3d9
PH
2263
2264Returns: HOST_FIND_FAILED couldn't find A record
2265 HOST_FIND_AGAIN try again later
2546388c 2266 HOST_FIND_SECURITY dnssec required but not acheived
059ec3d9
PH
2267 HOST_FOUND found AAAA and/or A record(s)
2268 HOST_IGNORED found, but all IPs ignored
2269*/
2270
2271static int
2272set_address_from_dns(host_item *host, host_item **lastptr,
55414b25
JH
2273 const uschar *ignore_target_hosts, BOOL allow_ip,
2274 const uschar **fully_qualified_name,
66387a73 2275 BOOL dnssec_request, BOOL dnssec_require, int whichrrs)
059ec3d9
PH
2276{
2277dns_record *rr;
2278host_item *thishostlast = NULL; /* Indicates not yet filled in anything */
2279BOOL v6_find_again = FALSE;
2546388c 2280BOOL dnssec_fail = FALSE;
059ec3d9
PH
2281int i;
2282
2283/* If allow_ip is set, a name which is an IP address returns that value
2284as its address. This is used for MX records when allow_mx_to_ip is set, for
2285those sites that feel they have to flaunt the RFC rules. */
2286
2287if (allow_ip && string_is_ip_address(host->name, NULL) != 0)
2288 {
2289 #ifndef STAND_ALONE
66387a73
JH
2290 if ( ignore_target_hosts
2291 && verify_check_this_host(&ignore_target_hosts, NULL, host->name,
059ec3d9
PH
2292 host->name, NULL) == OK)
2293 return HOST_IGNORED;
2294 #endif
2295
2296 host->address = host->name;
059ec3d9
PH
2297 return HOST_FOUND;
2298 }
2299
0539a19d 2300/* On an IPv6 system, unless IPv6 is disabled, go round the loop up to twice,
66387a73
JH
2301looking for AAAA records the first time. However, unless doing standalone
2302testing, we force an IPv4 lookup if the domain matches dns_ipv4_lookup global.
2303On an IPv4 system, go round the loop once only, looking only for A records. */
059ec3d9
PH
2304
2305#if HAVE_IPV6
059ec3d9 2306 #ifndef STAND_ALONE
66387a73
JH
2307 if ( disable_ipv6
2308 || !(whichrrs & HOST_FIND_BY_AAAA)
2309 || (dns_ipv4_lookup
2310 && match_isinlist(host->name, CUSS &dns_ipv4_lookup, 0, NULL, NULL,
2311 MCL_DOMAIN, TRUE, NULL) == OK)
2312 )
059ec3d9
PH
2313 i = 0; /* look up A records only */
2314 else
2315 #endif /* STAND_ALONE */
2316
059ec3d9 2317 i = 1; /* look up AAAA and A records */
059ec3d9
PH
2318
2319/* The IPv4 world */
2320
2321#else /* HAVE_IPV6 */
2322 i = 0; /* look up A records only */
2323#endif /* HAVE_IPV6 */
2324
2325for (; i >= 0; i--)
2326 {
0539a19d 2327 static int types[] = { T_A, T_AAAA };
059ec3d9 2328 int type = types[i];
66387a73
JH
2329 int randoffset = i == (whichrrs & HOST_FIND_IPV4_FIRST ? 1 : 0)
2330 ? 500 : 0; /* Ensures v6/4 sort order */
059ec3d9
PH
2331 dns_answer dnsa;
2332 dns_scan dnss;
2333
846430d9 2334 int rc = dns_lookup_timerwrap(&dnsa, host->name, type, fully_qualified_name);
cf2b569e 2335 lookup_dnssec_authenticated = !dnssec_request ? NULL
4e0983dc 2336 : dns_is_secure(&dnsa) ? US"yes" : US"no";
059ec3d9 2337
221dff13 2338 DEBUG(D_dns)
0539a19d
JH
2339 if ( (dnssec_request || dnssec_require)
2340 && !dns_is_secure(&dnsa)
2341 && dns_is_aa(&dnsa)
2342 )
2343 debug_printf("DNS lookup of %.256s (A/AAAA) requested AD, but got AA\n", host->name);
221dff13 2344
0539a19d 2345 /* We want to return HOST_FIND_AGAIN if one of the A or AAAA lookups
059ec3d9
PH
2346 fails or times out, but not if another one succeeds. (In the early
2347 IPv6 days there are name servers that always fail on AAAA, but are happy
2348 to give out an A record. We want to proceed with that A record.) */
8e669ac1 2349
059ec3d9
PH
2350 if (rc != DNS_SUCCEED)
2351 {
2352 if (i == 0) /* Just tried for an A record, i.e. end of loop */
2353 {
0539a19d 2354 if (host->address != NULL) return HOST_FOUND; /* AAAA was found */
059ec3d9
PH
2355 if (rc == DNS_AGAIN || rc == DNS_FAIL || v6_find_again)
2356 return HOST_FIND_AGAIN;
2357 return HOST_FIND_FAILED; /* DNS_NOMATCH or DNS_NODATA */
2358 }
2359
0539a19d 2360 /* Tried for an AAAA record: remember if this was a temporary
059ec3d9
PH
2361 error, and look for the next record type. */
2362
2363 if (rc != DNS_NOMATCH && rc != DNS_NODATA) v6_find_again = TRUE;
2364 continue;
2365 }
cf2b569e
JH
2366
2367 if (dnssec_request)
8c51eead 2368 {
cf2b569e
JH
2369 if (dns_is_secure(&dnsa))
2370 {
2371 DEBUG(D_host_lookup) debug_printf("%s A DNSSEC\n", host->name);
2372 if (host->dnssec == DS_UNK) /* set in host_find_bydns() */
2373 host->dnssec = DS_YES;
2374 }
2375 else
2376 {
2377 if (dnssec_require)
2378 {
2546388c
JH
2379 dnssec_fail = TRUE;
2380 DEBUG(D_host_lookup) debug_printf("dnssec fail on %s for %.256s",
0539a19d 2381 i>0 ? "AAAA" : "A", host->name);
cf2b569e
JH
2382 continue;
2383 }
2384 if (host->dnssec == DS_YES) /* set in host_find_bydns() */
2385 {
2386 DEBUG(D_host_lookup) debug_printf("%s A cancel DNSSEC\n", host->name);
2387 host->dnssec = DS_NO;
2388 lookup_dnssec_authenticated = US"no";
2389 }
2390 }
8c51eead 2391 }
059ec3d9
PH
2392
2393 /* Lookup succeeded: fill in the given host item with the first non-ignored
2394 address found; create additional items for any others. A single A6 record
8241d8dd
JH
2395 may generate more than one address. The lookup had a chance to update the
2396 fqdn; we do not want any later times round the loop to do so. */
2397
2398 fully_qualified_name = NULL;
059ec3d9
PH
2399
2400 for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
e1a3f32f 2401 rr;
059ec3d9
PH
2402 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
2403 {
2404 if (rr->type == type)
2405 {
d57d474f 2406 dns_address *da = dns_address_from_rr(&dnsa, rr);
059ec3d9
PH
2407
2408 DEBUG(D_host_lookup)
e1a3f32f 2409 if (!da) debug_printf("no addresses extracted from A6 RR for %s\n",
059ec3d9 2410 host->name);
059ec3d9
PH
2411
2412 /* This loop runs only once for A and AAAA records, but may run
2413 several times for an A6 record that generated multiple addresses. */
2414
e1a3f32f 2415 for (; da; da = da->next)
059ec3d9
PH
2416 {
2417 #ifndef STAND_ALONE
2418 if (ignore_target_hosts != NULL &&
2419 verify_check_this_host(&ignore_target_hosts, NULL,
2420 host->name, da->address, NULL) == OK)
2421 {
2422 DEBUG(D_host_lookup)
2423 debug_printf("ignored host %s [%s]\n", host->name, da->address);
2424 continue;
2425 }
2426 #endif
2427
2428 /* If this is the first address, stick it in the given host block,
2429 and change the name if the returned RR has a different name. */
2430
2431 if (thishostlast == NULL)
2432 {
2433 if (strcmpic(host->name, rr->name) != 0)
2434 host->name = string_copy_dnsdomain(rr->name);
2435 host->address = da->address;
059ec3d9
PH
2436 host->sort_key = host->mx * 1000 + random_number(500) + randoffset;
2437 host->status = hstatus_unknown;
2438 host->why = hwhy_unknown;
2439 thishostlast = host;
2440 }
2441
2442 /* Not the first address. Check for, and ignore, duplicates. Then
2443 insert in the chain at a random point. */
2444
2445 else
2446 {
2447 int new_sort_key;
2448 host_item *next;
2449
2450 /* End of our local chain is specified by "thishostlast". */
2451
2452 for (next = host;; next = next->next)
2453 {
2454 if (Ustrcmp(CS da->address, next->address) == 0) break;
2455 if (next == thishostlast) { next = NULL; break; }
2456 }
2457 if (next != NULL) continue; /* With loop for next address */
2458
2459 /* Not a duplicate */
2460
2461 new_sort_key = host->mx * 1000 + random_number(500) + randoffset;
2462 next = store_get(sizeof(host_item));
2463
2464 /* New address goes first: insert the new block after the first one
2465 (so as not to disturb the original pointer) but put the new address
2466 in the original block. */
2467
2468 if (new_sort_key < host->sort_key)
2469 {
1349e1e5 2470 *next = *host; /* Copies port */
059ec3d9
PH
2471 host->next = next;
2472 host->address = da->address;
059ec3d9
PH
2473 host->sort_key = new_sort_key;
2474 if (thishostlast == host) thishostlast = next; /* Local last */
2475 if (*lastptr == host) *lastptr = next; /* Global last */
2476 }
2477
2478 /* Otherwise scan down the addresses for this host to find the
2479 one to insert after. */
2480
2481 else
2482 {
2483 host_item *h = host;
2484 while (h != thishostlast)
2485 {
2486 if (new_sort_key < h->next->sort_key) break;
2487 h = h->next;
2488 }
1349e1e5 2489 *next = *h; /* Copies port */
059ec3d9
PH
2490 h->next = next;
2491 next->address = da->address;
059ec3d9
PH
2492 next->sort_key = new_sort_key;
2493 if (h == thishostlast) thishostlast = next; /* Local last */
2494 if (h == *lastptr) *lastptr = next; /* Global last */
2495 }
2496 }
2497 }
2498 }
2499 }
2500 }
2501
2546388c 2502/* Control gets here only if the second lookup (the A record) succeeded.
059ec3d9
PH
2503However, the address may not be filled in if it was ignored. */
2504
2546388c
JH
2505return host->address
2506 ? HOST_FOUND
2507 : dnssec_fail
2508 ? HOST_FIND_SECURITY
2509 : HOST_IGNORED;
059ec3d9
PH
2510}
2511
2512
2513
2514
2515/*************************************************
1349e1e5 2516* Find IP addresses and host names via DNS *
059ec3d9
PH
2517*************************************************/
2518
1349e1e5
PH
2519/* The input is a host_item structure with the name field filled in and the
2520address field set to NULL. This may be in a chain of other host items. The
2521lookup may result in more than one IP address, in which case we must created
2522new host blocks for the additional addresses, and insert them into the chain.
2523The original name may not be fully qualified. Use the fully_qualified_name
2524argument to return the official name, as returned by the resolver.
059ec3d9
PH
2525
2526Arguments:
2527 host point to initial host item
2528 ignore_target_hosts a list of hosts to ignore
2529 whichrrs flags indicating which RRs to look for:
2530 HOST_FIND_BY_SRV => look for SRV
2531 HOST_FIND_BY_MX => look for MX
66387a73
JH
2532 HOST_FIND_BY_A => look for A
2533 HOST_FIND_BY_AAAA => look for AAAA
059ec3d9
PH
2534 also flags indicating how the lookup is done
2535 HOST_FIND_QUALIFY_SINGLE ) passed to the
2536 HOST_FIND_SEARCH_PARENTS ) resolver
66387a73
JH
2537 HOST_FIND_IPV4_FIRST => reverse usual result ordering
2538 HOST_FIND_IPV4_ONLY => MX results elide ipv6
059ec3d9
PH
2539 srv_service when SRV used, the service name
2540 srv_fail_domains DNS errors for these domains => assume nonexist
2541 mx_fail_domains DNS errors for these domains => assume nonexist
7cd171b7
JH
2542 dnssec_d.request => make dnssec request: domainlist
2543 dnssec_d.require => ditto and nonexist failures
059ec3d9
PH
2544 fully_qualified_name if not NULL, return fully-qualified name
2545 removed set TRUE if local host was removed from the list
2546
2547Returns: HOST_FIND_FAILED Failed to find the host or domain;
2548 if there was a syntax error,
2549 host_find_failed_syntax is set.
2550 HOST_FIND_AGAIN Could not resolve at this time
2546388c 2551 HOST_FIND_SECURITY dnsssec required but not acheived
059ec3d9
PH
2552 HOST_FOUND Host found
2553 HOST_FOUND_LOCAL The lowest MX record points to this
2554 machine, if MX records were found, or
2555 an A record that was found contains
2556 an address of the local host
2557*/
2558
2559int
55414b25 2560host_find_bydns(host_item *host, const uschar *ignore_target_hosts, int whichrrs,
059ec3d9 2561 uschar *srv_service, uschar *srv_fail_domains, uschar *mx_fail_domains,
7cd171b7 2562 const dnssec_domains *dnssec_d,
55414b25 2563 const uschar **fully_qualified_name, BOOL *removed)
059ec3d9
PH
2564{
2565host_item *h, *last;
2566dns_record *rr;
2567int rc = DNS_FAIL;
2568int ind_type = 0;
2569int yield;
2570dns_answer dnsa;
2571dns_scan dnss;
7cd171b7
JH
2572BOOL dnssec_require = dnssec_d
2573 && match_isinlist(host->name, CUSS &dnssec_d->require,
8c51eead 2574 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK;
783b385f 2575BOOL dnssec_request = dnssec_require
7cd171b7
JH
2576 || ( dnssec_d
2577 && match_isinlist(host->name, CUSS &dnssec_d->request,
2578 0, NULL, NULL, MCL_DOMAIN, TRUE, NULL) == OK);
783b385f 2579dnssec_status_t dnssec;
059ec3d9
PH
2580
2581/* Set the default fully qualified name to the incoming name, initialize the
2582resolver if necessary, set up the relevant options, and initialize the flag
2583that gets set for DNS syntax check errors. */
2584
2585if (fully_qualified_name != NULL) *fully_qualified_name = host->name;
2586dns_init((whichrrs & HOST_FIND_QUALIFY_SINGLE) != 0,
8c51eead 2587 (whichrrs & HOST_FIND_SEARCH_PARENTS) != 0,
1f155f8e 2588 dnssec_request);
8768d548 2589f.host_find_failed_syntax = FALSE;
059ec3d9
PH
2590
2591/* First, if requested, look for SRV records. The service name is given; we
221dff13 2592assume TCP protocol. DNS domain names are constrained to a maximum of 256
059ec3d9
PH
2593characters, so the code below should be safe. */
2594
94759fce 2595if (whichrrs & HOST_FIND_BY_SRV)
059ec3d9 2596 {
d12746bc
JH
2597 gstring * g;
2598 uschar * temp_fully_qualified_name;
059ec3d9
PH
2599 int prefix_length;
2600
d12746bc
JH
2601 g = string_fmt_append(NULL, "_%s._tcp.%n%.256s",
2602 srv_service, &prefix_length, host->name);
2603 temp_fully_qualified_name = string_from_gstring(g);
059ec3d9
PH
2604 ind_type = T_SRV;
2605
2606 /* Search for SRV records. If the fully qualified name is different to
2607 the input name, pass back the new original domain, without the prepended
2608 magic. */
2609
783b385f
JH
2610 dnssec = DS_UNK;
2611 lookup_dnssec_authenticated = NULL;
d12746bc
JH
2612 rc = dns_lookup_timerwrap(&dnsa, temp_fully_qualified_name, ind_type,
2613 CUSS &temp_fully_qualified_name);
783b385f 2614
221dff13
HSHR
2615 DEBUG(D_dns)
2616 if ((dnssec_request || dnssec_require)
8f07c250
JH
2617 && !dns_is_secure(&dnsa)
2618 && dns_is_aa(&dnsa))
221dff13
HSHR
2619 debug_printf("DNS lookup of %.256s (SRV) requested AD, but got AA\n", host->name);
2620
783b385f
JH
2621 if (dnssec_request)
2622 {
2623 if (dns_is_secure(&dnsa))
2624 { dnssec = DS_YES; lookup_dnssec_authenticated = US"yes"; }
2625 else
2626 { dnssec = DS_NO; lookup_dnssec_authenticated = US"no"; }
2627 }
4e0983dc 2628
d12746bc 2629 if (temp_fully_qualified_name != g->s && fully_qualified_name != NULL)
059ec3d9
PH
2630 *fully_qualified_name = temp_fully_qualified_name + prefix_length;
2631
2632 /* On DNS failures, we give the "try again" error unless the domain is
2633 listed as one for which we continue. */
2634
8c51eead
JH
2635 if (rc == DNS_SUCCEED && dnssec_require && !dns_is_secure(&dnsa))
2636 {
2637 log_write(L_host_lookup_failed, LOG_MAIN,
2638 "dnssec fail on SRV for %.256s", host->name);
2639 rc = DNS_FAIL;
2640 }
059ec3d9
PH
2641 if (rc == DNS_FAIL || rc == DNS_AGAIN)
2642 {
e7726cbf 2643 #ifndef STAND_ALONE
55414b25
JH
2644 if (match_isinlist(host->name, CUSS &srv_fail_domains, 0, NULL, NULL,
2645 MCL_DOMAIN, TRUE, NULL) != OK)
e7726cbf 2646 #endif
8c51eead 2647 { yield = HOST_FIND_AGAIN; goto out; }
059ec3d9
PH
2648 DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA "
2649 "(domain in srv_fail_domains)\n", (rc == DNS_FAIL)? "FAIL":"AGAIN");
2650 }
2651 }
2652
2653/* If we did not find any SRV records, search the DNS for MX records, if
2654requested to do so. If the result is DNS_NOMATCH, it means there is no such
2655domain, and there's no point in going on to look for address records with the
2656same domain. The result will be DNS_NODATA if the domain exists but has no MX
2657records. On DNS failures, we give the "try again" error unless the domain is
2658listed as one for which we continue. */
2659
2546388c 2660if (rc != DNS_SUCCEED && whichrrs & HOST_FIND_BY_MX)
059ec3d9
PH
2661 {
2662 ind_type = T_MX;
783b385f
JH
2663 dnssec = DS_UNK;
2664 lookup_dnssec_authenticated = NULL;
846430d9 2665 rc = dns_lookup_timerwrap(&dnsa, host->name, ind_type, fully_qualified_name);
783b385f 2666
221dff13 2667 DEBUG(D_dns)
2546388c
JH
2668 if ( (dnssec_request || dnssec_require)
2669 && !dns_is_secure(&dnsa)
2670 && dns_is_aa(&dnsa))
cf3d165f 2671 debug_printf("DNS lookup of %.256s (MX) requested AD, but got AA\n", host->name);
221dff13 2672
783b385f 2673 if (dnssec_request)
783b385f 2674 if (dns_is_secure(&dnsa))
94431adb 2675 {
cf2b569e
JH
2676 DEBUG(D_host_lookup) debug_printf("%s MX DNSSEC\n", host->name);
2677 dnssec = DS_YES; lookup_dnssec_authenticated = US"yes";
2678 }
783b385f 2679 else
cf2b569e
JH
2680 {
2681 dnssec = DS_NO; lookup_dnssec_authenticated = US"no";
2682 }
4e0983dc 2683
8c51eead
JH
2684 switch (rc)
2685 {
2686 case DNS_NOMATCH:
2687 yield = HOST_FIND_FAILED; goto out;
2688
2689 case DNS_SUCCEED:
2690 if (!dnssec_require || dns_is_secure(&dnsa))
2691 break;
2546388c
JH
2692 DEBUG(D_host_lookup)
2693 debug_printf("dnssec fail on MX for %.256s", host->name);
2694#ifndef STAND_ALONE
2695 if (match_isinlist(host->name, CUSS &mx_fail_domains, 0, NULL, NULL,
2696 MCL_DOMAIN, TRUE, NULL) != OK)
2697 { yield = HOST_FIND_SECURITY; goto out; }
2698#endif
8c51eead 2699 rc = DNS_FAIL;
cf2b569e 2700 /*FALLTHROUGH*/
8c51eead
JH
2701
2702 case DNS_FAIL:
2703 case DNS_AGAIN:
2546388c 2704#ifndef STAND_ALONE
55414b25
JH
2705 if (match_isinlist(host->name, CUSS &mx_fail_domains, 0, NULL, NULL,
2706 MCL_DOMAIN, TRUE, NULL) != OK)
2546388c 2707#endif
8c51eead
JH
2708 { yield = HOST_FIND_AGAIN; goto out; }
2709 DEBUG(D_host_lookup) debug_printf("DNS_%s treated as DNS_NODATA "
2710 "(domain in mx_fail_domains)\n", (rc == DNS_FAIL)? "FAIL":"AGAIN");
2711 break;
059ec3d9
PH
2712 }
2713 }
2714
2715/* If we haven't found anything yet, and we are requested to do so, try for an
2716A or AAAA record. If we find it (or them) check to see that it isn't the local
2717host. */
2718
2719if (rc != DNS_SUCCEED)
2720 {
66387a73 2721 if (!(whichrrs & (HOST_FIND_BY_A | HOST_FIND_BY_AAAA)))
059ec3d9
PH
2722 {
2723 DEBUG(D_host_lookup) debug_printf("Address records are not being sought\n");
8c51eead
JH
2724 yield = HOST_FIND_FAILED;
2725 goto out;
059ec3d9
PH
2726 }
2727
2728 last = host; /* End of local chainlet */
2729 host->mx = MX_NONE;
2730 host->port = PORT_NONE;
cf2b569e 2731 host->dnssec = DS_UNK;
783b385f 2732 lookup_dnssec_authenticated = NULL;
059ec3d9 2733 rc = set_address_from_dns(host, &last, ignore_target_hosts, FALSE,
66387a73 2734 fully_qualified_name, dnssec_request, dnssec_require, whichrrs);
059ec3d9
PH
2735
2736 /* If one or more address records have been found, check that none of them
2737 are local. Since we know the host items all have their IP addresses
2738 inserted, host_scan_for_local_hosts() can only return HOST_FOUND or
2739 HOST_FOUND_LOCAL. We do not need to scan for duplicate IP addresses here,
2740 because set_address_from_dns() removes them. */
2741
2742 if (rc == HOST_FOUND)
2743 rc = host_scan_for_local_hosts(host, &last, removed);
2744 else
2745 if (rc == HOST_IGNORED) rc = HOST_FIND_FAILED; /* No special action */
2746
2747 DEBUG(D_host_lookup)
2748 {
2749 host_item *h;
2750 if (host->address != NULL)
2751 {
2752 if (fully_qualified_name != NULL)
2753 debug_printf("fully qualified name = %s\n", *fully_qualified_name);
2754 for (h = host; h != last->next; h = h->next)
2755 debug_printf("%s %s mx=%d sort=%d %s\n", h->name,
2756 (h->address == NULL)? US"<null>" : h->address, h->mx, h->sort_key,
2757 (h->status >= hstatus_unusable)? US"*" : US"");
2758 }
2759 }
2760
8c51eead
JH
2761 yield = rc;
2762 goto out;
059ec3d9
PH
2763 }
2764
2765/* We have found one or more MX or SRV records. Sort them according to
2766precedence. Put the data for the first one into the existing host block, and
2767insert new host_item blocks into the chain for the remainder. For equal
2768precedences one is supposed to randomize the order. To make this happen, the
2769sorting is actually done on the MX value * 1000 + a random number. This is put
2770into a host field called sort_key.
2771
2772In the case of hosts with both IPv6 and IPv4 addresses, we want to choose the
2773IPv6 address in preference. At this stage, we don't know what kind of address
2774the host has. We choose a random number < 500; if later we find an A record
2775first, we add 500 to the random number. Then for any other address records, we
2776use random numbers in the range 0-499 for AAAA records and 500-999 for A
2777records.
2778
2779At this point we remove any duplicates that point to the same host, retaining
2780only the one with the lowest precedence. We cannot yet check for precedence
2781greater than that of the local host, because that test cannot be properly done
2782until the addresses have been found - an MX record may point to a name for this
2783host which is not the primary hostname. */
2784
2785last = NULL; /* Indicates that not even the first item is filled yet */
2786
2787for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS);
dd708fd7
JH
2788 rr;
2789 rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) if (rr->type == ind_type)
059ec3d9
PH
2790 {
2791 int precedence;
2792 int weight = 0; /* For SRV records */
1349e1e5 2793 int port = PORT_NONE;
dd708fd7 2794 const uschar * s = rr->data; /* MUST be unsigned for GETSHORT */
059ec3d9
PH
2795 uschar data[256];
2796
059ec3d9
PH
2797 GETSHORT(precedence, s); /* Pointer s is advanced */
2798
2799 /* For MX records, we use a random "weight" which causes multiple records of
2800 the same precedence to sort randomly. */
2801
2802 if (ind_type == T_MX)
059ec3d9 2803 weight = random_number(500);
059ec3d9
PH
2804
2805 /* SRV records are specified with a port and a weight. The weight is used
2806 in a special algorithm. However, to start with, we just use it to order the
2807 records of equal priority (precedence). */
2808
2809 else
2810 {
2811 GETSHORT(weight, s);
2812 GETSHORT(port, s);
2813 }
2814
2815 /* Get the name of the host pointed to. */
2816
2817 (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, s,
2818 (DN_EXPAND_ARG4_TYPE)data, sizeof(data));
2819
2820 /* Check that we haven't already got this host on the chain; if we have,
2821 keep only the lower precedence. This situation shouldn't occur, but you
2822 never know what junk might get into the DNS (and this case has been seen on
2823 more than one occasion). */
2824
2825 if (last != NULL) /* This is not the first record */
2826 {
2827 host_item *prev = NULL;
2828
2829 for (h = host; h != last->next; prev = h, h = h->next)
2830 {
2831 if (strcmpic(h->name, data) == 0)
2832 {
2833 DEBUG(D_host_lookup)
2834 debug_printf("discarded duplicate host %s (MX=%d)\n", data,
2835 (precedence > h->mx)? precedence : h->mx);
2836 if (precedence >= h->mx) goto NEXT_MX_RR; /* Skip greater precedence */
2837 if (h == host) /* Override first item */
2838 {
2839 h->mx = precedence;
2840 host->sort_key = precedence * 1000 + weight;
2841 goto NEXT_MX_RR;
2842 }
2843
2844 /* Unwanted host item is not the first in the chain, so we can get
2845 get rid of it by cutting it out. */
2846
2847 prev->next = h->next;
2848 if (h == last) last = prev;
2849 break;
2850 }
2851 }
2852 }
2853
2854 /* If this is the first MX or SRV record, put the data into the existing host
2855 block. Otherwise, add a new block in the correct place; if it has to be
2856 before the first block, copy the first block's data to a new second block. */
2857
8ac90765 2858 if (!last)
059ec3d9
PH
2859 {
2860 host->name = string_copy_dnsdomain(data);
2861 host->address = NULL;
2862 host->port = port;
2863 host->mx = precedence;
2864 host->sort_key = precedence * 1000 + weight;
2865 host->status = hstatus_unknown;
2866 host->why = hwhy_unknown;
783b385f 2867 host->dnssec = dnssec;
059ec3d9
PH
2868 last = host;
2869 }
2870
2871 /* Make a new host item and seek the correct insertion place */
2872
2873 else
2874 {
2875 int sort_key = precedence * 1000 + weight;
2876 host_item *next = store_get(sizeof(host_item));
2877 next->name = string_copy_dnsdomain(data);
2878 next->address = NULL;
2879 next->port = port;
2880 next->mx = precedence;
2881 next->sort_key = sort_key;
2882 next->status = hstatus_unknown;
2883 next->why = hwhy_unknown;
783b385f 2884 next->dnssec = dnssec;
059ec3d9
PH
2885 next->last_try = 0;
2886
2887 /* Handle the case when we have to insert before the first item. */
2888
2889 if (sort_key < host->sort_key)
2890 {
2891 host_item htemp;
2892 htemp = *host;
2893 *host = *next;
2894 *next = htemp;
2895 host->next = next;
2896 if (last == host) last = next;
2897 }
2898
2899 /* Else scan down the items we have inserted as part of this exercise;
2900 don't go further. */
2901
2902 else
2903 {
2904 for (h = host; h != last; h = h->next)
2905 {
2906 if (sort_key < h->next->sort_key)
2907 {
2908 next->next = h->next;
2909 h->next = next;
2910 break;
2911 }
2912 }
2913
2914 /* Join on after the last host item that's part of this
2915 processing if we haven't stopped sooner. */
2916
2917 if (h == last)
2918 {
2919 next->next = last->next;
2920 last->next = next;
2921 last = next;
2922 }
2923 }
2924 }
2925
2926 NEXT_MX_RR: continue;
2927 }
2928
dc8091e7
JH
2929if (!last) /* No rr of correct type; give up */
2930 {
2931 yield = HOST_FIND_FAILED;
2932 goto out;
2933 }
2934
059ec3d9
PH
2935/* If the list of hosts was obtained from SRV records, there are two things to
2936do. First, if there is only one host, and it's name is ".", it means there is
2937no SMTP service at this domain. Otherwise, we have to sort the hosts of equal
2938priority according to their weights, using an algorithm that is defined in RFC
29392782. The hosts are currently sorted by priority and weight. For each priority
2940group we have to pick off one host and put it first, and then repeat for any
2941remaining in the same priority group. */
2942
2943if (ind_type == T_SRV)
2944 {
2945 host_item **pptr;
2946
2947 if (host == last && host->name[0] == 0)
2948 {
2949 DEBUG(D_host_lookup) debug_printf("the single SRV record is \".\"\n");
8c51eead
JH
2950 yield = HOST_FIND_FAILED;
2951 goto out;
059ec3d9
PH
2952 }
2953
2954 DEBUG(D_host_lookup)
2955 {
2956 debug_printf("original ordering of hosts from SRV records:\n");
2957 for (h = host; h != last->next; h = h->next)
2958 debug_printf(" %s P=%d W=%d\n", h->name, h->mx, h->sort_key % 1000);
2959 }
2960
dc8091e7 2961 for (pptr = &host, h = host; h != last; pptr = &h->next, h = h->next)
059ec3d9
PH
2962 {
2963 int sum = 0;
2964 host_item *hh;
2965
2966 /* Find the last following host that has the same precedence. At the same
2967 time, compute the sum of the weights and the running totals. These can be
2968 stored in the sort_key field. */
2969
2970 for (hh = h; hh != last; hh = hh->next)
2971 {
2972 int weight = hh->sort_key % 1000; /* was precedence * 1000 + weight */
2973 sum += weight;
2974 hh->sort_key = sum;
2975 if (hh->mx != hh->next->mx) break;
2976 }
2977
2978 /* If there's more than one host at this precedence (priority), we need to
2979 pick one to go first. */
2980
2981 if (hh != h)
2982 {
2983 host_item *hhh;
2984 host_item **ppptr;
2985 int randomizer = random_number(sum + 1);
2986
2987 for (ppptr = pptr, hhh = h;
2988 hhh != hh;
2989 ppptr = &(hhh->next), hhh = hhh->next)
2990 {
2991 if (hhh->sort_key >= randomizer) break;
2992 }
2993
2994 /* hhh now points to the host that should go first; ppptr points to the
2995 place that points to it. Unfortunately, if the start of the minilist is
2996 the start of the entire list, we can't just swap the items over, because
2997 we must not change the value of host, since it is passed in from outside.
2998 One day, this could perhaps be changed.
2999
3000 The special case is fudged by putting the new item *second* in the chain,
3001 and then transferring the data between the first and second items. We
3002 can't just swap the first and the chosen item, because that would mean
3003 that an item with zero weight might no longer be first. */
3004
3005 if (hhh != h)
3006 {
3007 *ppptr = hhh->next; /* Cuts it out of the chain */
3008
3009 if (h == host)
3010 {
3011 host_item temp = *h;
3012 *h = *hhh;
3013 *hhh = temp;
3014 hhh->next = temp.next;
3015 h->next = hhh;
3016 }
3017
3018 else
3019 {
3020 hhh->next = h; /* The rest of the chain follows it */
3021 *pptr = hhh; /* It takes the place of h */
3022 h = hhh; /* It's now the start of this minilist */
3023 }
3024 }
3025 }
3026
3027 /* A host has been chosen to be first at this priority and h now points
3028 to this host. There may be others at the same priority, or others at a
3029 different priority. Before we leave this host, we need to put back a sort
3030 key of the traditional MX kind, in case this host is multihomed, because
3031 the sort key is used for ordering the multiple IP addresses. We do not need
3032 to ensure that these new sort keys actually reflect the order of the hosts,
3033 however. */
3034
3035 h->sort_key = h->mx * 1000 + random_number(500);
3036 } /* Move on to the next host */
3037 }
3038
1349e1e5
PH
3039/* Now we have to find IP addresses for all the hosts. We have ensured above
3040that the names in all the host items are unique. Before release 4.61 we used to
3041process records from the additional section in the DNS packet that returned the
3042MX or SRV records. However, a DNS name server is free to drop any resource
3043records from the additional section. In theory, this has always been a
3044potential problem, but it is exacerbated by the advent of IPv6. If a host had
3045several IPv4 addresses and some were not in the additional section, at least
3046Exim would try the others. However, if a host had both IPv4 and IPv6 addresses
3047and all the IPv4 (say) addresses were absent, Exim would try only for a IPv6
3048connection, and never try an IPv4 address. When there was only IPv4
3049connectivity, this was a disaster that did in practice occur.
3050
3051So, from release 4.61 onwards, we always search for A and AAAA records
3052explicitly. The names shouldn't point to CNAMES, but we use the general lookup
3053function that handles them, just in case. If any lookup gives a soft error,
3054change the default yield.
059ec3d9
PH
3055
3056For these DNS lookups, we must disable qualify_single and search_parents;
3057otherwise invalid host names obtained from MX or SRV records can cause trouble
3058if they happen to match something local. */
3059
1349e1e5 3060yield = HOST_FIND_FAILED; /* Default yield */
8c51eead
JH
3061dns_init(FALSE, FALSE, /* Disable qualify_single and search_parents */
3062 dnssec_request || dnssec_require);
059ec3d9
PH
3063
3064for (h = host; h != last->next; h = h->next)
3065 {
dc8091e7
JH
3066 if (h->address) continue; /* Inserted by a multihomed host */
3067
8c51eead 3068 rc = set_address_from_dns(h, &last, ignore_target_hosts, allow_mx_to_ip,
66387a73
JH
3069 NULL, dnssec_request, dnssec_require,
3070 whichrrs & HOST_FIND_IPV4_ONLY
3071 ? HOST_FIND_BY_A : HOST_FIND_BY_A | HOST_FIND_BY_AAAA);
059ec3d9
PH
3072 if (rc != HOST_FOUND)
3073 {
3074 h->status = hstatus_unusable;
2546388c 3075 switch (rc)
059ec3d9 3076 {
66387a73
JH
3077 case HOST_FIND_AGAIN: yield = rc; h->why = hwhy_deferred; break;
3078 case HOST_FIND_SECURITY: yield = rc; h->why = hwhy_insecure; break;
3079 case HOST_IGNORED: h->why = hwhy_ignored; break;
3080 default: h->why = hwhy_failed; break;
059ec3d9 3081 }
059ec3d9
PH
3082 }
3083 }
3084
3085/* Scan the list for any hosts that are marked unusable because they have
3086been explicitly ignored, and remove them from the list, as if they did not
3087exist. If we end up with just a single, ignored host, flatten its fields as if
3088nothing was found. */
3089
2546388c 3090if (ignore_target_hosts)
059ec3d9
PH
3091 {
3092 host_item *prev = NULL;
3093 for (h = host; h != last->next; h = h->next)
3094 {
3095 REDO:
3096 if (h->why != hwhy_ignored) /* Non ignored host, just continue */
3097 prev = h;
3098 else if (prev == NULL) /* First host is ignored */
3099 {
3100 if (h != last) /* First is not last */
3101 {
3102 if (h->next == last) last = h; /* Overwrite it with next */
3103 *h = *(h->next); /* and reprocess it. */
3104 goto REDO; /* C should have redo, like Perl */
3105 }
3106 }
3107 else /* Ignored host is not first - */
3108 { /* cut it out */
3109 prev->next = h->next;
3110 if (h == last) last = prev;
3111 }
3112 }
3113
3114 if (host->why == hwhy_ignored) host->address = NULL;
3115 }
3116
3117/* There is still one complication in the case of IPv6. Although the code above
3118arranges that IPv6 addresses take precedence over IPv4 addresses for multihomed
3119hosts, it doesn't do this for addresses that apply to different hosts with the
3120same MX precedence, because the sorting on MX precedence happens first. So we
3121have to make another pass to check for this case. We ensure that, within a
3122single MX preference value, IPv6 addresses come first. This can separate the
3123addresses of a multihomed host, but that should not matter. */
3124
3125#if HAVE_IPV6
2546388c 3126if (h != last && !disable_ipv6) for (h = host; h != last; h = h->next)
059ec3d9 3127 {
2546388c
JH
3128 host_item temp;
3129 host_item *next = h->next;
3130
66387a73
JH
3131 if ( h->mx != next->mx /* If next is different MX */
3132 || !h->address /* OR this one is unset */
3133 )
3134 continue; /* move on to next */
3135
3136 if ( whichrrs & HOST_FIND_IPV4_FIRST
3137 ? !Ustrchr(h->address, ':') /* OR this one is IPv4 */
3138 || next->address
3139 && Ustrchr(next->address, ':') /* OR next is IPv6 */
3140
3141 : Ustrchr(h->address, ':') /* OR this one is IPv6 */
3142 || next->address
3143 && !Ustrchr(next->address, ':') /* OR next is IPv4 */
3144 )
2546388c 3145 continue; /* move on to next */
66387a73 3146
2546388c
JH
3147 temp = *h; /* otherwise, swap */
3148 temp.next = next->next;
3149 *h = *next;
3150 h->next = next;
3151 *next = temp;
059ec3d9
PH
3152 }
3153#endif
3154
059ec3d9
PH
3155/* Remove any duplicate IP addresses and then scan the list of hosts for any
3156whose IP addresses are on the local host. If any are found, all hosts with the
3157same or higher MX values are removed. However, if the local host has the lowest
3158numbered MX, then HOST_FOUND_LOCAL is returned. Otherwise, if at least one host
3159with an IP address is on the list, HOST_FOUND is returned. Otherwise,
3160HOST_FIND_FAILED is returned, but in this case do not update the yield, as it
3161might have been set to HOST_FIND_AGAIN just above here. If not, it will already
3162be HOST_FIND_FAILED. */
3163
3164host_remove_duplicates(host, &last);
3165rc = host_scan_for_local_hosts(host, &last, removed);
3166if (rc != HOST_FIND_FAILED) yield = rc;
3167
3168DEBUG(D_host_lookup)
3169 {
3170 if (fully_qualified_name != NULL)
3171 debug_printf("fully qualified name = %s\n", *fully_qualified_name);
3172 debug_printf("host_find_bydns yield = %s (%d); returned hosts:\n",
3173 (yield == HOST_FOUND)? "HOST_FOUND" :
3174 (yield == HOST_FOUND_LOCAL)? "HOST_FOUND_LOCAL" :
2546388c 3175 (yield == HOST_FIND_SECURITY)? "HOST_FIND_SECURITY" :
059ec3d9
PH
3176 (yield == HOST_FIND_AGAIN)? "HOST_FIND_AGAIN" :
3177 (yield == HOST_FIND_FAILED)? "HOST_FIND_FAILED" : "?",
3178 yield);
3179 for (h = host; h != last->next; h = h->next)
3180 {
805c9d53
JH
3181 debug_printf(" %s %s MX=%d %s", h->name,
3182 !h->address ? US"<null>" : h->address, h->mx,
3183 h->dnssec == DS_YES ? US"DNSSEC " : US"");
059ec3d9
PH
3184 if (h->port != PORT_NONE) debug_printf("port=%d ", h->port);
3185 if (h->status >= hstatus_unusable) debug_printf("*");
3186 debug_printf("\n");
3187 }
3188 }
3189
8c51eead
JH
3190out:
3191
3192dns_init(FALSE, FALSE, FALSE); /* clear the dnssec bit for getaddrbyname */
059ec3d9
PH
3193return yield;
3194}
3195
059ec3d9
PH
3196/*************************************************
3197**************************************************
3198* Stand-alone test program *
3199**************************************************
3200*************************************************/
3201
3202#ifdef STAND_ALONE
3203
059ec3d9
PH
3204int main(int argc, char **cargv)
3205{
3206host_item h;
66387a73 3207int whichrrs = HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
059ec3d9
PH
3208BOOL byname = FALSE;
3209BOOL qualify_single = TRUE;
3210BOOL search_parents = FALSE;
8c51eead
JH
3211BOOL request_dnssec = FALSE;
3212BOOL require_dnssec = FALSE;
059ec3d9
PH
3213uschar **argv = USS cargv;
3214uschar buffer[256];
3215
322050c2 3216disable_ipv6 = FALSE;
059ec3d9
PH
3217primary_hostname = US"";
3218store_pool = POOL_MAIN;
3219debug_selector = D_host_lookup|D_interface;
3220debug_file = stdout;
3221debug_fd = fileno(debug_file);
3222
3223printf("Exim stand-alone host functions test\n");
3224
3225host_find_interfaces();
3226debug_selector = D_host_lookup | D_dns;
3227
3228if (argc > 1) primary_hostname = argv[1];
3229
3230/* So that debug level changes can be done first */
3231
8c51eead 3232dns_init(qualify_single, search_parents, FALSE);
059ec3d9
PH
3233
3234printf("Testing host lookup\n");
3235printf("> ");
3236while (Ufgets(buffer, 256, stdin) != NULL)
3237 {
3238 int rc;
3239 int len = Ustrlen(buffer);
3240 uschar *fully_qualified_name;
3241
3242 while (len > 0 && isspace(buffer[len-1])) len--;
3243 buffer[len] = 0;
3244
3245 if (Ustrcmp(buffer, "q") == 0) break;
3246
3247 if (Ustrcmp(buffer, "byname") == 0) byname = TRUE;
3248 else if (Ustrcmp(buffer, "no_byname") == 0) byname = FALSE;
66387a73 3249 else if (Ustrcmp(buffer, "a_only") == 0) whichrrs = HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
059ec3d9
PH
3250 else if (Ustrcmp(buffer, "mx_only") == 0) whichrrs = HOST_FIND_BY_MX;
3251 else if (Ustrcmp(buffer, "srv_only") == 0) whichrrs = HOST_FIND_BY_SRV;
3252 else if (Ustrcmp(buffer, "srv+a") == 0)
66387a73 3253 whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
059ec3d9
PH
3254 else if (Ustrcmp(buffer, "srv+mx") == 0)
3255 whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX;
3256 else if (Ustrcmp(buffer, "srv+mx+a") == 0)
66387a73 3257 whichrrs = HOST_FIND_BY_SRV | HOST_FIND_BY_MX | HOST_FIND_BY_A | HOST_FIND_BY_AAAA;
8c51eead 3258 else if (Ustrcmp(buffer, "qualify_single") == 0) qualify_single = TRUE;
059ec3d9 3259 else if (Ustrcmp(buffer, "no_qualify_single") == 0) qualify_single = FALSE;
8c51eead 3260 else if (Ustrcmp(buffer, "search_parents") == 0) search_parents = TRUE;
059ec3d9 3261 else if (Ustrcmp(buffer, "no_search_parents") == 0) search_parents = FALSE;
8c51eead
JH
3262 else if (Ustrcmp(buffer, "request_dnssec") == 0) request_dnssec = TRUE;
3263 else if (Ustrcmp(buffer, "no_request_dnssec") == 0) request_dnssec = FALSE;
3264 else if (Ustrcmp(buffer, "require_dnssec") == 0) require_dnssec = TRUE;
f988ce57 3265 else if (Ustrcmp(buffer, "no_require_dnssec") == 0) require_dnssec = FALSE;
e7726cbf 3266 else if (Ustrcmp(buffer, "test_harness") == 0)
8768d548 3267 f.running_in_test_harness = !f.running_in_test_harness;
322050c2 3268 else if (Ustrcmp(buffer, "ipv6") == 0) disable_ipv6 = !disable_ipv6;
e7726cbf
PH
3269 else if (Ustrcmp(buffer, "res_debug") == 0)
3270 {
3271 _res.options ^= RES_DEBUG;
3272 }
059ec3d9
PH
3273 else if (Ustrncmp(buffer, "retrans", 7) == 0)
3274 {
ff790e47 3275 (void)sscanf(CS(buffer+8), "%d", &dns_retrans);
059ec3d9
PH
3276 _res.retrans = dns_retrans;
3277 }
3278 else if (Ustrncmp(buffer, "retry", 5) == 0)
3279 {
ff790e47 3280 (void)sscanf(CS(buffer+6), "%d", &dns_retry);
059ec3d9
PH
3281 _res.retry = dns_retry;
3282 }
059ec3d9
PH
3283 else
3284 {
3285 int flags = whichrrs;
505d976a 3286 dnssec_domains d;
059ec3d9
PH
3287
3288 h.name = buffer;
3289 h.next = NULL;
3290 h.mx = MX_NONE;
3291 h.port = PORT_NONE;
3292 h.status = hstatus_unknown;
3293 h.why = hwhy_unknown;
3294 h.address = NULL;
3295
3296 if (qualify_single) flags |= HOST_FIND_QUALIFY_SINGLE;
3297 if (search_parents) flags |= HOST_FIND_SEARCH_PARENTS;
3298
7cd171b7
JH
3299 d.request = request_dnssec ? &h.name : NULL;
3300 d.require = require_dnssec ? &h.name : NULL;
3301
8c51eead
JH
3302 rc = byname
3303 ? host_find_byname(&h, NULL, flags, &fully_qualified_name, TRUE)
3304 : host_find_bydns(&h, NULL, flags, US"smtp", NULL, NULL,
7cd171b7 3305 &d, &fully_qualified_name, NULL);
059ec3d9 3306
2546388c
JH
3307 switch (rc)
3308 {
3309 case HOST_FIND_FAILED: printf("Failed\n"); break;
3310 case HOST_FIND_AGAIN: printf("Again\n"); break;
3311 case HOST_FIND_SECURITY: printf("Security\n"); break;
3312 case HOST_FOUND_LOCAL: printf("Local\n"); break;
3313 }
059ec3d9
PH
3314 }
3315
3316 printf("\n> ");
3317 }
3318
3319printf("Testing host_aton\n");
3320printf("> ");
3321while (Ufgets(buffer, 256, stdin) != NULL)
3322 {
3323 int i;
3324 int x[4];
3325 int len = Ustrlen(buffer);
3326
3327 while (len > 0 && isspace(buffer[len-1])) len--;
3328 buffer[len] = 0;
3329
3330 if (Ustrcmp(buffer, "q") == 0) break;
3331
3332 len = host_aton(buffer, x);
3333 printf("length = %d ", len);
3334 for (i = 0; i < len; i++)
3335 {
3336 printf("%04x ", (x[i] >> 16) & 0xffff);
3337 printf("%04x ", x[i] & 0xffff);
3338 }
3339 printf("\n> ");
3340 }
3341
3342printf("\n");
3343
3344printf("Testing host_name_lookup\n");
3345printf("> ");
3346while (Ufgets(buffer, 256, stdin) != NULL)
3347 {
3348 int len = Ustrlen(buffer);
3349 while (len > 0 && isspace(buffer[len-1])) len--;
3350 buffer[len] = 0;
3351 if (Ustrcmp(buffer, "q") == 0) break;
3352 sender_host_address = buffer;
3353 sender_host_name = NULL;
3354 sender_host_aliases = NULL;
3355 host_lookup_msg = US"";
3356 host_lookup_failed = FALSE;
3357 if (host_name_lookup() == FAIL) /* Debug causes printing */
3358 printf("Lookup failed:%s\n", host_lookup_msg);
3359 printf("\n> ");
3360 }
3361
3362printf("\n");
3363
3364return 0;
3365}
3366#endif /* STAND_ALONE */
3367
8c51eead
JH
3368/* vi: aw ai sw=2
3369*/
059ec3d9 3370/* End of host.c */