1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
4 /* DMARC support.
5 Copyright (c) Todd Lyons <tlyons@exim.org> 2012 - 2014
6 Copyright (c) The Exim Maintainers 2019
7 License: GPL */
8
9 /* Portions Copyright (c) 2012, 2013, The Trusted Domain Project;
10 All rights reserved, licensed for use per LICENSE.opendmarc. */
11
12 /* Code for calling dmarc checks via libopendmarc. Called from acl.c. */
13
14 #include "exim.h"
15 #ifdef SUPPORT_DMARC
16 # if !defined SUPPORT_SPF
17 # error SPF must also be enabled for DMARC
18 # elif defined DISABLE_DKIM
19 # error DKIM must also be enabled for DMARC
20 # else
21
22 # include "functions.h"
23 # include "dmarc.h"
24 # include "pdkim/pdkim.h"
25
26 OPENDMARC_LIB_T dmarc_ctx;
27 DMARC_POLICY_T *dmarc_pctx = NULL;
28 OPENDMARC_STATUS_T libdm_status, action, dmarc_policy;
29 OPENDMARC_STATUS_T da, sa, action;
30 BOOL dmarc_abort = FALSE;
31 uschar *dmarc_pass_fail = US"skipped";
32 header_line *from_header = NULL;
33 extern SPF_response_t *spf_response;
34 int dmarc_spf_ares_result = 0;
35 uschar *spf_sender_domain = NULL;
36 uschar *spf_human_readable = NULL;
37 u_char *header_from_sender = NULL;
38 int history_file_status = DMARC_HIST_OK;
39 uschar *dkim_history_buffer= NULL;
40 uschar *dkim_selector = NULL;
41
42 typedef struct dmarc_exim_p {
43 uschar *name;
44 int value;
45 } dmarc_exim_p;
46
47 static dmarc_exim_p dmarc_policy_description[] = {
48 /* name value */
49 { US"", DMARC_RECORD_P_UNSPECIFIED },
50 { US"none", DMARC_RECORD_P_NONE },
51 { US"quarantine", DMARC_RECORD_P_QUARANTINE },
52 { US"reject", DMARC_RECORD_P_REJECT },
53 { NULL, 0 }
54 };
55
56
57 void
dmarc_version_report(FILE * f)58 dmarc_version_report(FILE *f)
59 {
60 const char *implementation, *version;
61
62 fprintf(f, "Library version: dmarc: Compile: %d.%d.%d.%d\n",
63 (OPENDMARC_LIB_VERSION & 0xff000000) >> 24, (OPENDMARC_LIB_VERSION & 0x00ff0000) >> 16,
64 (OPENDMARC_LIB_VERSION & 0x0000ff00) >> 8, OPENDMARC_LIB_VERSION & 0x000000ff);
65 }
66
67
68 /* Accept an error_block struct, initialize if empty, parse to the
69 end, and append the two strings passed to it. Used for adding
70 variable amounts of value:pair data to the forensic emails. */
71
72 static error_block *
add_to_eblock(error_block * eblock,uschar * t1,uschar * t2)73 add_to_eblock(error_block *eblock, uschar *t1, uschar *t2)
74 {
75 error_block *eb = store_malloc(sizeof(error_block));
76 if (!eblock)
77 eblock = eb;
78 else
79 {
80 /* Find the end of the eblock struct and point it at eb */
81 error_block *tmp = eblock;
82 while(tmp->next)
83 tmp = tmp->next;
84 tmp->next = eb;
85 }
86 eb->text1 = t1;
87 eb->text2 = t2;
88 eb->next = NULL;
89 return eblock;
90 }
91
92 /* dmarc_init sets up a context that can be re-used for several
93 messages on the same SMTP connection (that come from the
94 same host with the same HELO string) */
95
96 int
dmarc_init()97 dmarc_init()
98 {
99 int *netmask = NULL; /* Ignored */
100 int is_ipv6 = 0;
101
102 /* Set some sane defaults. Also clears previous results when
103 * multiple messages in one connection. */
104 dmarc_pctx = NULL;
105 dmarc_status = US"none";
106 dmarc_abort = FALSE;
107 dmarc_pass_fail = US"skipped";
108 dmarc_used_domain = US"";
109 f.dmarc_has_been_checked = FALSE;
110 header_from_sender = NULL;
111 spf_sender_domain = NULL;
112 spf_human_readable = NULL;
113
114 /* ACLs have "control=dmarc_disable_verify" */
115 if (f.dmarc_disable_verify == TRUE)
116 return OK;
117
118 (void) memset(&dmarc_ctx, '\0', sizeof dmarc_ctx);
119 dmarc_ctx.nscount = 0;
120 libdm_status = opendmarc_policy_library_init(&dmarc_ctx);
121 if (libdm_status != DMARC_PARSE_OKAY)
122 {
123 log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure to init library: %s",
124 opendmarc_policy_status_to_str(libdm_status));
125 dmarc_abort = TRUE;
126 }
127 if (!dmarc_tld_file || !*dmarc_tld_file)
128 {
129 DEBUG(D_receive) debug_printf("DMARC: no dmarc_tld_file\n");
130 dmarc_abort = TRUE;
131 }
132 else if (opendmarc_tld_read_file(CS dmarc_tld_file, NULL, NULL, NULL))
133 {
134 log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure to load tld list '%s': %s",
135 dmarc_tld_file, strerror(errno));
136 dmarc_abort = TRUE;
137 }
138 if (!sender_host_address)
139 {
140 DEBUG(D_receive) debug_printf("DMARC: no sender_host_address\n");
141 dmarc_abort = TRUE;
142 }
143 /* This catches locally originated email and startup errors above. */
144 if (!dmarc_abort)
145 {
146 is_ipv6 = string_is_ip_address(sender_host_address, netmask) == 6;
147 if (!(dmarc_pctx = opendmarc_policy_connect_init(sender_host_address, is_ipv6)))
148 {
149 log_write(0, LOG_MAIN|LOG_PANIC,
150 "DMARC failure creating policy context: ip=%s", sender_host_address);
151 dmarc_abort = TRUE;
152 }
153 }
154
155 return OK;
156 }
157
158
159 /* dmarc_store_data stores the header data so that subsequent
160 dmarc_process can access the data */
161
162 int
dmarc_store_data(header_line * hdr)163 dmarc_store_data(header_line *hdr)
164 {
165 /* No debug output because would change every test debug output */
166 if (!f.dmarc_disable_verify)
167 from_header = hdr;
168 return OK;
169 }
170
171
172 static void
dmarc_send_forensic_report(u_char ** ruf)173 dmarc_send_forensic_report(u_char **ruf)
174 {
175 uschar *recipient, *save_sender;
176 BOOL send_status = FALSE;
177 error_block *eblock = NULL;
178 FILE *message_file = NULL;
179
180 /* Earlier ACL does not have *required* control=dmarc_enable_forensic */
181 if (!f.dmarc_enable_forensic)
182 return;
183
184 if ( dmarc_policy == DMARC_POLICY_REJECT && action == DMARC_RESULT_REJECT
185 || dmarc_policy == DMARC_POLICY_QUARANTINE && action == DMARC_RESULT_QUARANTINE
186 || dmarc_policy == DMARC_POLICY_NONE && action == DMARC_RESULT_REJECT
187 || dmarc_policy == DMARC_POLICY_NONE && action == DMARC_RESULT_QUARANTINE
188 )
189 if (ruf)
190 {
191 eblock = add_to_eblock(eblock, US"Sender Domain", dmarc_used_domain);
192 eblock = add_to_eblock(eblock, US"Sender IP Address", sender_host_address);
193 eblock = add_to_eblock(eblock, US"Received Date", tod_stamp(tod_full));
194 eblock = add_to_eblock(eblock, US"SPF Alignment",
195 sa == DMARC_POLICY_SPF_ALIGNMENT_PASS ? US"yes" : US"no");
196 eblock = add_to_eblock(eblock, US"DKIM Alignment",
197 da == DMARC_POLICY_DKIM_ALIGNMENT_PASS ? US"yes" : US"no");
198 eblock = add_to_eblock(eblock, US"DMARC Results", dmarc_status_text);
199
200 for (int c = 0; ruf[c]; c++)
201 {
202 recipient = string_copylc(ruf[c]);
203 if (Ustrncmp(recipient, "mailto:",7))
204 continue;
205 /* Move to first character past the colon */
206 recipient += 7;
207 DEBUG(D_receive)
208 debug_printf("DMARC forensic report to %s%s\n", recipient,
209 (host_checking || f.running_in_test_harness) ? " (not really)" : "");
210 if (host_checking || f.running_in_test_harness)
211 continue;
212
213 if (!moan_send_message(recipient, ERRMESS_DMARC_FORENSIC, eblock,
214 header_list, message_file, NULL))
215 log_write(0, LOG_MAIN|LOG_PANIC,
216 "failure to send DMARC forensic report to %s", recipient);
217 }
218 }
219 }
220
221
222 /* Look up a DNS dmarc record for the given domain. Return it or NULL */
223
224 static uschar *
dmarc_dns_lookup(uschar * dom)225 dmarc_dns_lookup(uschar * dom)
226 {
227 dns_answer * dnsa = store_get_dns_answer();
228 dns_scan dnss;
229 int rc = dns_lookup(dnsa, string_sprintf("_dmarc.%s", dom), T_TXT, NULL);
230
231 if (rc == DNS_SUCCEED)
232 for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
233 rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
234 if (rr->type == T_TXT && rr->size > 3)
235 {
236 store_free_dns_answer(dnsa);
237 return string_copyn_taint(US rr->data, rr->size, TRUE);
238 }
239 store_free_dns_answer(dnsa);
240 return NULL;
241 }
242
243
244 static int
dmarc_write_history_file()245 dmarc_write_history_file()
246 {
247 int history_file_fd;
248 ssize_t written_len;
249 int tmp_ans;
250 u_char **rua; /* aggregate report addressees */
251 uschar *history_buffer = NULL;
252
253 if (!dmarc_history_file)
254 {
255 DEBUG(D_receive) debug_printf("DMARC history file not set\n");
256 return DMARC_HIST_DISABLED;
257 }
258 history_file_fd = log_open_as_exim(dmarc_history_file);
259
260 if (history_file_fd < 0)
261 {
262 log_write(0, LOG_MAIN|LOG_PANIC, "failure to create DMARC history file: %s",
263 dmarc_history_file);
264 return DMARC_HIST_FILE_ERR;
265 }
266
267 /* Generate the contents of the history file */
268 history_buffer = string_sprintf(
269 "job %s\nreporter %s\nreceived %ld\nipaddr %s\nfrom %s\nmfrom %s\n",
270 message_id, primary_hostname, time(NULL), sender_host_address,
271 header_from_sender, expand_string(US"$sender_address_domain"));
272
273 if (spf_response)
274 history_buffer = string_sprintf("%sspf %d\n", history_buffer, dmarc_spf_ares_result);
275 /* history_buffer = string_sprintf("%sspf -1\n", history_buffer); */
276
277 history_buffer = string_sprintf(
278 "%s%spdomain %s\npolicy %d\n",
279 history_buffer, dkim_history_buffer, dmarc_used_domain, dmarc_policy);
280
281 if ((rua = opendmarc_policy_fetch_rua(dmarc_pctx, NULL, 0, 1)))
282 for (tmp_ans = 0; rua[tmp_ans]; tmp_ans++)
283 history_buffer = string_sprintf("%srua %s\n", history_buffer, rua[tmp_ans]);
284 else
285 history_buffer = string_sprintf("%srua -\n", history_buffer);
286
287 opendmarc_policy_fetch_pct(dmarc_pctx, &tmp_ans);
288 history_buffer = string_sprintf("%spct %d\n", history_buffer, tmp_ans);
289
290 opendmarc_policy_fetch_adkim(dmarc_pctx, &tmp_ans);
291 history_buffer = string_sprintf("%sadkim %d\n", history_buffer, tmp_ans);
292
293 opendmarc_policy_fetch_aspf(dmarc_pctx, &tmp_ans);
294 history_buffer = string_sprintf("%saspf %d\n", history_buffer, tmp_ans);
295
296 opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
297 history_buffer = string_sprintf("%sp %d\n", history_buffer, tmp_ans);
298
299 opendmarc_policy_fetch_sp(dmarc_pctx, &tmp_ans);
300 history_buffer = string_sprintf("%ssp %d\n", history_buffer, tmp_ans);
301
302 history_buffer = string_sprintf(
303 "%salign_dkim %d\nalign_spf %d\naction %d\n",
304 history_buffer, da, sa, action);
305
306 /* Write the contents to the history file */
307 DEBUG(D_receive)
308 debug_printf("DMARC logging history data for opendmarc reporting%s\n",
309 (host_checking || f.running_in_test_harness) ? " (not really)" : "");
310 if (host_checking || f.running_in_test_harness)
311 {
312 DEBUG(D_receive)
313 debug_printf("DMARC history data for debugging:\n%s", history_buffer);
314 }
315 else
316 {
317 written_len = write_to_fd_buf(history_file_fd,
318 history_buffer,
319 Ustrlen(history_buffer));
320 if (written_len == 0)
321 {
322 log_write(0, LOG_MAIN|LOG_PANIC, "failure to write to DMARC history file: %s",
323 dmarc_history_file);
324 return DMARC_HIST_WRITE_ERR;
325 }
326 (void)close(history_file_fd);
327 }
328 return DMARC_HIST_OK;
329 }
330
331
332 /* dmarc_process adds the envelope sender address to the existing
333 context (if any), retrieves the result, sets up expansion
334 strings and evaluates the condition outcome. */
335
336 int
dmarc_process()337 dmarc_process()
338 {
339 int sr, origin; /* used in SPF section */
340 int dmarc_spf_result = 0; /* stores spf into dmarc conn ctx */
341 int tmp_ans, c;
342 pdkim_signature * sig = dkim_signatures;
343 uschar * rr;
344 BOOL has_dmarc_record = TRUE;
345 u_char **ruf; /* forensic report addressees, if called for */
346
347 /* ACLs have "control=dmarc_disable_verify" */
348 if (f.dmarc_disable_verify)
349 return OK;
350
351 /* Store the header From: sender domain for this part of DMARC.
352 * If there is no from_header struct, then it's likely this message
353 * is locally generated and relying on fixups to add it. Just skip
354 * the entire DMARC system if we can't find a From: header....or if
355 * there was a previous error.
356 */
357 if (!from_header)
358 {
359 DEBUG(D_receive) debug_printf("DMARC: no From: header\n");
360 dmarc_abort = TRUE;
361 }
362 else if (!dmarc_abort)
363 {
364 uschar * errormsg;
365 int dummy, domain;
366 uschar * p;
367 uschar saveend;
368
369 f.parse_allow_group = TRUE;
370 p = parse_find_address_end(from_header->text, FALSE);
371 saveend = *p; *p = '\0';
372 if ((header_from_sender = parse_extract_address(from_header->text, &errormsg,
373 &dummy, &dummy, &domain, FALSE)))
374 header_from_sender += domain;
375 *p = saveend;
376
377 /* The opendmarc library extracts the domain from the email address, but
378 * only try to store it if it's not empty. Otherwise, skip out of DMARC. */
379 if (!header_from_sender || (strcmp( CCS header_from_sender, "") == 0))
380 dmarc_abort = TRUE;
381 libdm_status = dmarc_abort
382 ? DMARC_PARSE_OKAY
383 : opendmarc_policy_store_from_domain(dmarc_pctx, header_from_sender);
384 if (libdm_status != DMARC_PARSE_OKAY)
385 {
386 log_write(0, LOG_MAIN|LOG_PANIC,
387 "failure to store header From: in DMARC: %s, header was '%s'",
388 opendmarc_policy_status_to_str(libdm_status), from_header->text);
389 dmarc_abort = TRUE;
390 }
391 }
392
393 /* Skip DMARC if connection is SMTP Auth. Temporarily, admin should
394 * instead do this in the ACLs. */
395 if (!dmarc_abort && !sender_host_authenticated)
396 {
397 uschar * dmarc_domain;
398
399 /* Use the envelope sender domain for this part of DMARC */
400 spf_sender_domain = expand_string(US"$sender_address_domain");
401 if (!spf_response)
402 {
403 /* No spf data means null envelope sender so generate a domain name
404 * from the sender_helo_name */
405 if (!spf_sender_domain)
406 {
407 spf_sender_domain = sender_helo_name;
408 log_write(0, LOG_MAIN, "DMARC using synthesized SPF sender domain = %s\n",
409 spf_sender_domain);
410 DEBUG(D_receive)
411 debug_printf("DMARC using synthesized SPF sender domain = %s\n",
412 spf_sender_domain);
413 }
414 dmarc_spf_result = DMARC_POLICY_SPF_OUTCOME_NONE;
415 dmarc_spf_ares_result = ARES_RESULT_UNKNOWN;
416 origin = DMARC_POLICY_SPF_ORIGIN_HELO;
417 spf_human_readable = US"";
418 }
419 else
420 {
421 sr = spf_response->result;
422 dmarc_spf_result = sr == SPF_RESULT_NEUTRAL ? DMARC_POLICY_SPF_OUTCOME_NONE :
423 sr == SPF_RESULT_PASS ? DMARC_POLICY_SPF_OUTCOME_PASS :
424 sr == SPF_RESULT_FAIL ? DMARC_POLICY_SPF_OUTCOME_FAIL :
425 sr == SPF_RESULT_SOFTFAIL ? DMARC_POLICY_SPF_OUTCOME_TMPFAIL :
426 DMARC_POLICY_SPF_OUTCOME_NONE;
427 dmarc_spf_ares_result = sr == SPF_RESULT_NEUTRAL ? ARES_RESULT_NEUTRAL :
428 sr == SPF_RESULT_PASS ? ARES_RESULT_PASS :
429 sr == SPF_RESULT_FAIL ? ARES_RESULT_FAIL :
430 sr == SPF_RESULT_SOFTFAIL ? ARES_RESULT_SOFTFAIL :
431 sr == SPF_RESULT_NONE ? ARES_RESULT_NONE :
432 sr == SPF_RESULT_TEMPERROR ? ARES_RESULT_TEMPERROR :
433 sr == SPF_RESULT_PERMERROR ? ARES_RESULT_PERMERROR :
434 ARES_RESULT_UNKNOWN;
435 origin = DMARC_POLICY_SPF_ORIGIN_MAILFROM;
436 spf_human_readable = US spf_response->header_comment;
437 DEBUG(D_receive)
438 debug_printf("DMARC using SPF sender domain = %s\n", spf_sender_domain);
439 }
440 if (strcmp( CCS spf_sender_domain, "") == 0)
441 dmarc_abort = TRUE;
442 if (!dmarc_abort)
443 {
444 libdm_status = opendmarc_policy_store_spf(dmarc_pctx, spf_sender_domain,
445 dmarc_spf_result, origin, spf_human_readable);
446 if (libdm_status != DMARC_PARSE_OKAY)
447 log_write(0, LOG_MAIN|LOG_PANIC, "failure to store spf for DMARC: %s",
448 opendmarc_policy_status_to_str(libdm_status));
449 }
450
451 /* Now we cycle through the dkim signature results and put into
452 * the opendmarc context, further building the DMARC reply. */
453 dkim_history_buffer = US"";
454 while (sig)
455 {
456 int dkim_result, dkim_ares_result, vs, ves;
457
458 vs = sig->verify_status & ~PDKIM_VERIFY_POLICY;
459 ves = sig->verify_ext_status;
460 dkim_result = vs == PDKIM_VERIFY_PASS ? DMARC_POLICY_DKIM_OUTCOME_PASS :
461 vs == PDKIM_VERIFY_FAIL ? DMARC_POLICY_DKIM_OUTCOME_FAIL :
462 vs == PDKIM_VERIFY_INVALID ? DMARC_POLICY_DKIM_OUTCOME_TMPFAIL :
463 DMARC_POLICY_DKIM_OUTCOME_NONE;
464 libdm_status = opendmarc_policy_store_dkim(dmarc_pctx, US sig->domain,
465 dkim_selector, dkim_result, US"");
466 DEBUG(D_receive)
467 debug_printf("DMARC adding DKIM sender domain = %s\n", sig->domain);
468 if (libdm_status != DMARC_PARSE_OKAY)
469 log_write(0, LOG_MAIN|LOG_PANIC,
470 "failure to store dkim (%s) for DMARC: %s",
471 sig->domain, opendmarc_policy_status_to_str(libdm_status));
472
473 dkim_ares_result =
474 vs == PDKIM_VERIFY_PASS ? ARES_RESULT_PASS :
475 vs == PDKIM_VERIFY_FAIL ? ARES_RESULT_FAIL :
476 vs == PDKIM_VERIFY_NONE ? ARES_RESULT_NONE :
477 vs == PDKIM_VERIFY_INVALID ?
478 ves == PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE ? ARES_RESULT_PERMERROR :
479 ves == PDKIM_VERIFY_INVALID_BUFFER_SIZE ? ARES_RESULT_PERMERROR :
480 ves == PDKIM_VERIFY_INVALID_PUBKEY_DNSRECORD ? ARES_RESULT_PERMERROR :
481 ves == PDKIM_VERIFY_INVALID_PUBKEY_IMPORT ? ARES_RESULT_PERMERROR :
482 ARES_RESULT_UNKNOWN :
483 ARES_RESULT_UNKNOWN;
484 dkim_history_buffer = string_sprintf("%sdkim %s %d\n", dkim_history_buffer,
485 sig->domain, dkim_ares_result);
486 sig = sig->next;
487 }
488
489 /* Look up DMARC policy record in DNS. We do this explicitly, rather than
490 letting the dmarc library do it with opendmarc_policy_query_dmarc(), so that
491 our dns access path is used for debug tracing and for the testsuite
492 diversion. */
493
494 libdm_status = (rr = dmarc_dns_lookup(header_from_sender))
495 ? opendmarc_policy_store_dmarc(dmarc_pctx, rr, header_from_sender, NULL)
496 : DMARC_DNS_ERROR_NO_RECORD;
497 switch (libdm_status)
498 {
499 case DMARC_DNS_ERROR_NXDOMAIN:
500 case DMARC_DNS_ERROR_NO_RECORD:
501 DEBUG(D_receive)
502 debug_printf("DMARC no record found for %s\n", header_from_sender);
503 has_dmarc_record = FALSE;
504 break;
505 case DMARC_PARSE_OKAY:
506 DEBUG(D_receive)
507 debug_printf("DMARC record found for %s\n", header_from_sender);
508 break;
509 case DMARC_PARSE_ERROR_BAD_VALUE:
510 DEBUG(D_receive)
511 debug_printf("DMARC record parse error for %s\n", header_from_sender);
512 has_dmarc_record = FALSE;
513 break;
514 default:
515 /* everything else, skip dmarc */
516 DEBUG(D_receive)
517 debug_printf("DMARC skipping (%d), unsure what to do with %s",
518 libdm_status, from_header->text);
519 has_dmarc_record = FALSE;
520 break;
521 }
522
523 /* Store the policy string in an expandable variable. */
524
525 libdm_status = opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
526 for (c = 0; dmarc_policy_description[c].name; c++)
527 if (tmp_ans == dmarc_policy_description[c].value)
528 {
529 dmarc_domain_policy = string_sprintf("%s",dmarc_policy_description[c].name);
530 break;
531 }
532
533 /* Can't use exim's string manipulation functions so allocate memory
534 for libopendmarc using its max hostname length definition. */
535
536 dmarc_domain = store_get(DMARC_MAXHOSTNAMELEN, TRUE);
537 libdm_status = opendmarc_policy_fetch_utilized_domain(dmarc_pctx,
538 dmarc_domain, DMARC_MAXHOSTNAMELEN-1);
539 store_release_above(dmarc_domain + Ustrlen(dmarc_domain)+1);
540 dmarc_used_domain = dmarc_domain;
541
542 if (libdm_status != DMARC_PARSE_OKAY)
543 log_write(0, LOG_MAIN|LOG_PANIC,
544 "failure to read domainname used for DMARC lookup: %s",
545 opendmarc_policy_status_to_str(libdm_status));
546
547 dmarc_policy = libdm_status = opendmarc_get_policy_to_enforce(dmarc_pctx);
548 switch(libdm_status)
549 {
550 case DMARC_POLICY_ABSENT: /* No DMARC record found */
551 dmarc_status = US"norecord";
552 dmarc_pass_fail = US"none";
553 dmarc_status_text = US"No DMARC record";
554 action = DMARC_RESULT_ACCEPT;
555 break;
556 case DMARC_FROM_DOMAIN_ABSENT: /* No From: domain */
557 dmarc_status = US"nofrom";
558 dmarc_pass_fail = US"temperror";
559 dmarc_status_text = US"No From: domain found";
560 action = DMARC_RESULT_ACCEPT;
561 break;
562 case DMARC_POLICY_NONE: /* Accept and report */
563 dmarc_status = US"none";
564 dmarc_pass_fail = US"none";
565 dmarc_status_text = US"None, Accept";
566 action = DMARC_RESULT_ACCEPT;
567 break;
568 case DMARC_POLICY_PASS: /* Explicit accept */
569 dmarc_status = US"accept";
570 dmarc_pass_fail = US"pass";
571 dmarc_status_text = US"Accept";
572 action = DMARC_RESULT_ACCEPT;
573 break;
574 case DMARC_POLICY_REJECT: /* Explicit reject */
575 dmarc_status = US"reject";
576 dmarc_pass_fail = US"fail";
577 dmarc_status_text = US"Reject";
578 action = DMARC_RESULT_REJECT;
579 break;
580 case DMARC_POLICY_QUARANTINE: /* Explicit quarantine */
581 dmarc_status = US"quarantine";
582 dmarc_pass_fail = US"fail";
583 dmarc_status_text = US"Quarantine";
584 action = DMARC_RESULT_QUARANTINE;
585 break;
586 default:
587 dmarc_status = US"temperror";
588 dmarc_pass_fail = US"temperror";
589 dmarc_status_text = US"Internal Policy Error";
590 action = DMARC_RESULT_TEMPFAIL;
591 break;
592 }
593
594 libdm_status = opendmarc_policy_fetch_alignment(dmarc_pctx, &da, &sa);
595 if (libdm_status != DMARC_PARSE_OKAY)
596 log_write(0, LOG_MAIN|LOG_PANIC, "failure to read DMARC alignment: %s",
597 opendmarc_policy_status_to_str(libdm_status));
598
599 if (has_dmarc_record)
600 {
601 log_write(0, LOG_MAIN, "DMARC results: spf_domain=%s dmarc_domain=%s "
602 "spf_align=%s dkim_align=%s enforcement='%s'",
603 spf_sender_domain, dmarc_used_domain,
604 sa==DMARC_POLICY_SPF_ALIGNMENT_PASS ?"yes":"no",
605 da==DMARC_POLICY_DKIM_ALIGNMENT_PASS ?"yes":"no",
606 dmarc_status_text);
607 history_file_status = dmarc_write_history_file();
608 /* Now get the forensic reporting addresses, if any */
609 ruf = opendmarc_policy_fetch_ruf(dmarc_pctx, NULL, 0, 1);
610 dmarc_send_forensic_report(ruf);
611 }
612 }
613
614 /* shut down libopendmarc */
615 if (dmarc_pctx)
616 (void) opendmarc_policy_connect_shutdown(dmarc_pctx);
617 if (!f.dmarc_disable_verify)
618 (void) opendmarc_policy_library_shutdown(&dmarc_ctx);
619
620 return OK;
621 }
622
623 uschar *
dmarc_exim_expand_query(int what)624 dmarc_exim_expand_query(int what)
625 {
626 if (f.dmarc_disable_verify || !dmarc_pctx)
627 return dmarc_exim_expand_defaults(what);
628
629 if (what == DMARC_VERIFY_STATUS)
630 return dmarc_status;
631 return US"";
632 }
633
634 uschar *
dmarc_exim_expand_defaults(int what)635 dmarc_exim_expand_defaults(int what)
636 {
637 if (what == DMARC_VERIFY_STATUS)
638 return f.dmarc_disable_verify ? US"off" : US"none";
639 return US"";
640 }
641
642
643 gstring *
authres_dmarc(gstring * g)644 authres_dmarc(gstring * g)
645 {
646 if (f.dmarc_has_been_checked)
647 {
648 g = string_append(g, 2, US";\n\tdmarc=", dmarc_pass_fail);
649 if (header_from_sender)
650 g = string_append(g, 2, US" header.from=", header_from_sender);
651 }
652 return g;
653 }
654
655 # endif /* SUPPORT_SPF */
656 #endif /* SUPPORT_DMARC */
657 /* vi: aw ai sw=2
658 */
659