src/src/dmarc.c

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