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, 2013
   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
  16 #include "functions.h"
  17 #include "dmarc.h"
  18 #include "pdkim/pdkim.h"
  19
  20 OPENDMARC_LIB_T     dmarc_ctx;
  21 DMARC_POLICY_T     *dmarc_pctx = NULL;
  22 OPENDMARC_STATUS_T  libdm_status, action, dmarc_policy;
  23 OPENDMARC_STATUS_T  da, sa, action;
  24 BOOL dmarc_abort  = FALSE;
  25 uschar *dmarc_pass_fail = US"skipped";
  26 extern pdkim_signature  *dkim_signatures;
  27 header_line *from_header   = NULL;
  28 #ifdef EXPERIMENTAL_SPF
  29 extern SPF_response_t   *spf_response;
  30 int    dmarc_spf_result     = 0;
  31 uschar *spf_sender_domain  = NULL;
  32 uschar *spf_human_readable = NULL;
  33 #endif
  34 u_char *header_from_sender = NULL;
  35 int history_file_status    = DMARC_HIST_OK;
  36 uschar *history_buffer     = NULL;
  37 uschar *dkim_history_buffer= NULL;
  38
  39 /* Accept an error_block struct, initialize if empty, parse to the
  40  * end, and append the two strings passed to it.  Used for adding
  41  * variable amounts of value:pair data to the forensic emails. */
  42
  43 static error_block *
  44 add_to_eblock(error_block *eblock, uschar *t1, uschar *t2)
  45 {
  46   error_block *eb = malloc(sizeof(error_block));
  47   if (eblock == NULL)
  48     eblock = eb;
  49   else
  50   {
  51     /* Find the end of the eblock struct and point it at eb */
  52     error_block *tmp = eblock;
  53     while(tmp->next != NULL)
  54       tmp = tmp->next;
  55     tmp->next = eb;
  56   }
  57   eb->text1 = t1;
  58   eb->text2 = t2;
  59   eb->next  = NULL;
  60   return eblock;
  61 }
  62
  63 /* dmarc_init sets up a context that can be re-used for several
  64    messages on the same SMTP connection (that come from the
  65    same host with the same HELO string) */
  66
  67 int dmarc_init() {
  68   int *netmask   = NULL;   /* Ignored */
  69   int is_ipv6    = 0;
  70   char *tld_file = (dmarc_tld_file == NULL) ?
  71                    "/etc/exim/opendmarc.tlds" :
  72                    (char *)dmarc_tld_file;
  73
  74   /* Set some sane defaults.  Also clears previous results when
  75    * multiple messages in one connection. */
  76   dmarc_pctx         = NULL;
  77   dmarc_status       = US"none";
  78   dmarc_abort        = FALSE;
  79   dmarc_pass_fail    = US"skipped";
  80   dmarc_used_domain  = US"";
  81   header_from_sender = NULL;
  82 #ifdef EXPERIMENTAL_SPF
  83   spf_sender_domain  = NULL;
  84   spf_human_readable = NULL;
  85 #endif
  86
  87   /* ACLs have "control=dmarc_disable_verify" */
  88   if (dmarc_disable_verify == TRUE)
  89     return OK;
  90
  91   (void) memset(&dmarc_ctx, '\0', sizeof dmarc_ctx);
  92   dmarc_ctx.nscount = 0;
  93   libdm_status = opendmarc_policy_library_init(&dmarc_ctx);
  94   if (libdm_status != DMARC_PARSE_OKAY)
  95   {
  96     log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure to init library: %s",
  97                          opendmarc_policy_status_to_str(libdm_status));
  98     dmarc_abort = TRUE;
  99   }
 100   if (opendmarc_tld_read_file(tld_file, NULL, NULL, NULL))
 101   {
 102     log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure to load tld list %s: %d",
 103                          tld_file, errno);
 104     dmarc_abort = TRUE;
 105   }
 106   if (sender_host_address == NULL)
 107     dmarc_abort = TRUE;
 108   /* This catches locally originated email and startup errors above. */
 109   if ( dmarc_abort == FALSE )
 110   {
 111     is_ipv6 = string_is_ip_address(sender_host_address, netmask);
 112     is_ipv6 = (is_ipv6 == 6) ? TRUE :
 113               (is_ipv6 == 4) ? FALSE : FALSE;
 114     dmarc_pctx = opendmarc_policy_connect_init(sender_host_address, is_ipv6);
 115     if (dmarc_pctx == NULL )
 116     {
 117       log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure creating policy context: ip=%s",
 118                                        sender_host_address);
 119       dmarc_abort = TRUE;
 120     }
 121   }
 122
 123   return OK;
 124 }
 125
 126
 127 /* dmarc_store_data stores the header data so that subsequent
 128  * dmarc_process can access the data */
 129
 130 int dmarc_store_data(header_line *hdr) {
 131   /* No debug output because would change every test debug output */
 132   if (dmarc_disable_verify != TRUE)
 133     from_header = hdr;
 134   return OK;
 135 }
 136
 137
 138 /* dmarc_process adds the envelope sender address to the existing
 139    context (if any), retrieves the result, sets up expansion
 140    strings and evaluates the condition outcome. */
 141
 142 int dmarc_process() {
 143     int sr, origin; /* used in SPF section */
 144     pdkim_signature *sig  = NULL;
 145     BOOL has_dmarc_record = TRUE;
 146     u_char **ruf; /* forensic report addressees, if called for */
 147
 148   /* ACLs have "control=dmarc_disable_verify" */
 149   if (dmarc_disable_verify == TRUE)
 150   {
 151     dmarc_ar_header = dmarc_auth_results_header(from_header, NULL);
 152     return OK;
 153   }
 154
 155   /* Store the header From: sender domain for this part of DMARC.
 156    * If there is no from_header struct, then it's likely this message
 157    * is locally generated and relying on fixups to add it.  Just skip
 158    * the entire DMARC system if we can't find a From: header....or if
 159    * there was a previous error.
 160    */
 161   if (from_header == NULL || dmarc_abort == TRUE)
 162     dmarc_abort = TRUE;
 163   else
 164   {
 165     /* I strongly encourage anybody who can make this better to contact me directly!
 166      * <cannonball> Is this an insane way to extract the email address from the From: header?
 167      * <jgh_hm> it's sure a horrid layer-crossing....
 168      * <cannonball> I'm not denying that :-/
 169      * <jgh_hm> there may well be no better though
 170      */
 171     header_from_sender = expand_string(
 172                            string_sprintf("${domain:${extract{1}{:}{${addresses:%s}}}}",
 173                              from_header->text) );
 174     /* The opendmarc library extracts the domain from the email address, but
 175      * only try to store it if it's not empty.  Otherwise, skip out of DMARC. */
 176     if (strcmp( CCS header_from_sender, "") == 0)
 177       dmarc_abort = TRUE;
 178     libdm_status = (dmarc_abort == TRUE) ?
 179                    DMARC_PARSE_OKAY :
 180                    opendmarc_policy_store_from_domain(dmarc_pctx, header_from_sender);
 181     if (libdm_status != DMARC_PARSE_OKAY)
 182     {
 183       log_write(0, LOG_MAIN|LOG_PANIC, "failure to store header From: in DMARC: %s, header was '%s'",
 184                            opendmarc_policy_status_to_str(libdm_status), from_header->text);
 185       dmarc_abort = TRUE;
 186     }
 187   }
 188
 189   /* Skip DMARC if connection is SMTP Auth. Temporarily, admin should
 190    * instead do this in the ACLs.  */
 191   if (dmarc_abort == FALSE && sender_host_authenticated == NULL)
 192   {
 193 #ifdef EXPERIMENTAL_SPF
 194     /* Use the envelope sender domain for this part of DMARC */
 195     spf_sender_domain = expand_string(US"$sender_address_domain");
 196     if ( spf_response == NULL )
 197     {
 198       /* No spf data means null envelope sender so generate a domain name
 199        * from the sender_host_name || sender_helo_name  */
 200       if (spf_sender_domain == NULL)
 201       {
 202         spf_sender_domain = (sender_host_name == NULL) ? sender_helo_name : sender_host_name;
 203         uschar *subdomain = spf_sender_domain;
 204         int count = 0;
 205         while (subdomain && *subdomain != '.')
 206         {
 207           subdomain++;
 208           count++;
 209         }
 210         /* If parsed characters in temp var "subdomain" and is pointing to
 211          * a period now, get rid of the period and use that.  Otherwise
 212          * will use whatever was first set in spf_sender_domain.  Goal is to
 213          * generate a sane answer, not necessarily the right/best answer b/c
 214          * at this point with a null sender, it's a bounce message, making
 215          * the spf domain be subjective.  */
 216         if (count > 0 && *subdomain == '.')
 217         {
 218           subdomain++;
 219           spf_sender_domain = subdomain;
 220         }
 221         log_write(0, LOG_MAIN, "DMARC using synthesized SPF sender domain = %s\n",
 222                                spf_sender_domain);
 223         DEBUG(D_receive)
 224           debug_printf("DMARC using synthesized SPF sender domain = %s\n", spf_sender_domain);
 225       }
 226       dmarc_spf_result = DMARC_POLICY_SPF_OUTCOME_NONE;
 227       origin = DMARC_POLICY_SPF_ORIGIN_HELO;
 228       spf_human_readable = US"";
 229     }
 230     else
 231     {
 232       sr = spf_response->result;
 233       dmarc_spf_result = (sr == SPF_RESULT_NEUTRAL)  ? DMARC_POLICY_SPF_OUTCOME_NONE :
 234                          (sr == SPF_RESULT_PASS)     ? DMARC_POLICY_SPF_OUTCOME_PASS :
 235                          (sr == SPF_RESULT_FAIL)     ? DMARC_POLICY_SPF_OUTCOME_FAIL :
 236                          (sr == SPF_RESULT_SOFTFAIL) ? DMARC_POLICY_SPF_OUTCOME_TMPFAIL :
 237                          DMARC_POLICY_SPF_OUTCOME_NONE;
 238       origin = DMARC_POLICY_SPF_ORIGIN_MAILFROM;
 239       spf_human_readable = (uschar *)spf_response->header_comment;
 240       DEBUG(D_receive)
 241         debug_printf("DMARC using SPF sender domain = %s\n", spf_sender_domain);
 242     }
 243     if (strcmp( CCS spf_sender_domain, "") == 0)
 244       dmarc_abort = TRUE;
 245     if (dmarc_abort == FALSE)
 246     {
 247       libdm_status = opendmarc_policy_store_spf(dmarc_pctx, spf_sender_domain,
 248                                                 dmarc_spf_result, origin, spf_human_readable);
 249       if (libdm_status != DMARC_PARSE_OKAY)
 250         log_write(0, LOG_MAIN|LOG_PANIC, "failure to store spf for DMARC: %s",
 251                              opendmarc_policy_status_to_str(libdm_status));
 252     }
 253 #endif /* EXPERIMENTAL_SPF */
 254
 255     /* Now we cycle through the dkim signature results and put into
 256      * the opendmarc context, further building the DMARC reply.  */
 257     sig = dkim_signatures;
 258     dkim_history_buffer = US"";
 259     while (sig != NULL)
 260     {
 261       int dkim_result, vs;
 262       vs = sig->verify_status;
 263       dkim_result = ( vs == PDKIM_VERIFY_PASS ) ? DMARC_POLICY_DKIM_OUTCOME_PASS :
 264                     ( vs == PDKIM_VERIFY_FAIL ) ? DMARC_POLICY_DKIM_OUTCOME_FAIL :
 265                     ( vs == PDKIM_VERIFY_INVALID ) ? DMARC_POLICY_DKIM_OUTCOME_TMPFAIL :
 266                     DMARC_POLICY_DKIM_OUTCOME_NONE;
 267       libdm_status = opendmarc_policy_store_dkim(dmarc_pctx, (uschar *)sig->domain,
 268                                                  dkim_result, US"");
 269       DEBUG(D_receive)
 270         debug_printf("DMARC adding DKIM sender domain = %s\n", sig->domain);
 271       if (libdm_status != DMARC_PARSE_OKAY)
 272         log_write(0, LOG_MAIN|LOG_PANIC, "failure to store dkim (%s) for DMARC: %s",
 273                              sig->domain, opendmarc_policy_status_to_str(libdm_status));
 274
 275       dkim_history_buffer = string_sprintf("%sdkim %s %d\n", dkim_history_buffer,
 276                                                              sig->domain, dkim_result);
 277       sig = sig->next;
 278     }
 279     libdm_status = opendmarc_policy_query_dmarc(dmarc_pctx, US"");
 280     switch (libdm_status)
 281     {
 282       case DMARC_DNS_ERROR_NXDOMAIN:
 283       case DMARC_DNS_ERROR_NO_RECORD:
 284         DEBUG(D_receive)
 285           debug_printf("DMARC no record found for %s\n", header_from_sender);
 286         has_dmarc_record = FALSE;
 287         break;
 288       case DMARC_PARSE_OKAY:
 289         DEBUG(D_receive)
 290           debug_printf("DMARC record found for %s\n", header_from_sender);
 291         break;
 292       case DMARC_PARSE_ERROR_BAD_VALUE:
 293         DEBUG(D_receive)
 294           debug_printf("DMARC record parse error for %s\n", header_from_sender);
 295         has_dmarc_record = FALSE;
 296         break;
 297       default:
 298         /* everything else, skip dmarc */
 299         DEBUG(D_receive)
 300           debug_printf("DMARC skipping (%d), unsure what to do with %s",
 301                         libdm_status, from_header->text);
 302         has_dmarc_record = FALSE;
 303         break;
 304     }
 305     /* Can't use exim's string manipulation functions so allocate memory
 306      * for libopendmarc using its max hostname length definition. */
 307     uschar *dmarc_domain = (uschar *)calloc(DMARC_MAXHOSTNAMELEN, sizeof(uschar));
 308     libdm_status = opendmarc_policy_fetch_utilized_domain(dmarc_pctx, dmarc_domain,
 309                                                           DMARC_MAXHOSTNAMELEN-1);
 310     dmarc_used_domain = string_copy(dmarc_domain);
 311     free(dmarc_domain);
 312     if (libdm_status != DMARC_PARSE_OKAY)
 313     {
 314       log_write(0, LOG_MAIN|LOG_PANIC, "failure to read domainname used for DMARC lookup: %s",
 315                                        opendmarc_policy_status_to_str(libdm_status));
 316     }
 317     libdm_status = opendmarc_get_policy_to_enforce(dmarc_pctx);
 318     dmarc_policy = libdm_status;
 319     switch(libdm_status)
 320     {
 321       case DMARC_POLICY_ABSENT:     /* No DMARC record found */
 322         dmarc_status = US"norecord";
 323         dmarc_pass_fail = US"temperror";
 324         dmarc_status_text = US"No DMARC record";
 325         action = DMARC_RESULT_ACCEPT;
 326         break;
 327       case DMARC_FROM_DOMAIN_ABSENT:    /* No From: domain */
 328         dmarc_status = US"nofrom";
 329         dmarc_pass_fail = US"temperror";
 330         dmarc_status_text = US"No From: domain found";
 331         action = DMARC_RESULT_ACCEPT;
 332         break;
 333       case DMARC_POLICY_NONE:       /* Accept and report */
 334         dmarc_status = US"none";
 335         dmarc_pass_fail = US"none";
 336         dmarc_status_text = US"None, Accept";
 337         action = DMARC_RESULT_ACCEPT;
 338         break;
 339       case DMARC_POLICY_PASS:       /* Explicit accept */
 340         dmarc_status = US"accept";
 341         dmarc_pass_fail = US"pass";
 342         dmarc_status_text = US"Accept";
 343         action = DMARC_RESULT_ACCEPT;
 344         break;
 345       case DMARC_POLICY_REJECT:       /* Explicit reject */
 346         dmarc_status = US"reject";
 347         dmarc_pass_fail = US"fail";
 348         dmarc_status_text = US"Reject";
 349         action = DMARC_RESULT_REJECT;
 350         break;
 351       case DMARC_POLICY_QUARANTINE:       /* Explicit quarantine */
 352         dmarc_status = US"quarantine";
 353         dmarc_pass_fail = US"fail";
 354         dmarc_status_text = US"Quarantine";
 355         action = DMARC_RESULT_QUARANTINE;
 356         break;
 357       default:
 358         dmarc_status = US"temperror";
 359         dmarc_pass_fail = US"temperror";
 360         dmarc_status_text = US"Internal Policy Error";
 361         action = DMARC_RESULT_TEMPFAIL;
 362         break;
 363     }
 364
 365     libdm_status = opendmarc_policy_fetch_alignment(dmarc_pctx, &da, &sa);
 366     if (libdm_status != DMARC_PARSE_OKAY)
 367     {
 368       log_write(0, LOG_MAIN|LOG_PANIC, "failure to read DMARC alignment: %s",
 369                                        opendmarc_policy_status_to_str(libdm_status));
 370     }
 371
 372     if (has_dmarc_record == TRUE)
 373     {
 374       log_write(0, LOG_MAIN, "DMARC results: spf_domain=%s dmarc_domain=%s "
 375                              "spf_align=%s dkim_align=%s enforcement='%s'",
 376                              spf_sender_domain, dmarc_used_domain,
 377                              (sa==DMARC_POLICY_SPF_ALIGNMENT_PASS) ?"yes":"no",
 378                              (da==DMARC_POLICY_DKIM_ALIGNMENT_PASS)?"yes":"no",
 379                              dmarc_status_text);
 380       history_file_status = dmarc_write_history_file();
 381       /* Now get the forensic reporting addresses, if any */
 382       ruf = opendmarc_policy_fetch_ruf(dmarc_pctx, NULL, 0, 1);
 383       dmarc_send_forensic_report(ruf);
 384     }
 385   }
 386
 387   /* set some global variables here */
 388   dmarc_ar_header = dmarc_auth_results_header(from_header, NULL);
 389
 390   /* shut down libopendmarc */
 391   if ( dmarc_pctx != NULL )
 392     (void) opendmarc_policy_connect_shutdown(dmarc_pctx);
 393   if ( dmarc_disable_verify == FALSE )
 394     (void) opendmarc_policy_library_shutdown(&dmarc_ctx);
 395
 396   return OK;
 397 }
 398
 399 int dmarc_write_history_file()
 400 {
 401   static int history_file_fd;
 402   ssize_t written_len;
 403   int tmp_ans;
 404   u_char **rua; /* aggregate report addressees */
 405
 406   if (dmarc_history_file == NULL)
 407     return DMARC_HIST_DISABLED;
 408   history_file_fd = log_create(dmarc_history_file);
 409
 410   if (history_file_fd < 0)
 411   {
 412     log_write(0, LOG_MAIN|LOG_PANIC, "failure to create DMARC history file: %s",
 413                              dmarc_history_file);
 414     return DMARC_HIST_FILE_ERR;
 415   }
 416
 417   /* Generate the contents of the history file */
 418   history_buffer = string_sprintf("job %s\n", message_id);
 419   history_buffer = string_sprintf("%sreporter %s\n", history_buffer, primary_hostname);
 420   history_buffer = string_sprintf("%sreceived %ld\n", history_buffer, time(NULL));
 421   history_buffer = string_sprintf("%sipaddr %s\n", history_buffer, sender_host_address);
 422   history_buffer = string_sprintf("%sfrom %s\n", history_buffer, header_from_sender);
 423   history_buffer = string_sprintf("%smfrom %s\n", history_buffer,
 424                      expand_string(US"$sender_address_domain"));
 425
 426 #ifdef EXPERIMENTAL_SPF
 427   if (spf_response != NULL)
 428     history_buffer = string_sprintf("%sspf %d\n", history_buffer, dmarc_spf_result);
 429 #else
 430     history_buffer = string_sprintf("%sspf -1\n", history_buffer);
 431 #endif /* EXPERIMENTAL_SPF */
 432
 433   history_buffer = string_sprintf("%s%s", history_buffer, dkim_history_buffer);
 434   history_buffer = string_sprintf("%spdomain %s\n", history_buffer, dmarc_used_domain);
 435   history_buffer = string_sprintf("%spolicy %d\n", history_buffer, dmarc_policy);
 436
 437   rua = opendmarc_policy_fetch_rua(dmarc_pctx, NULL, 0, 1);
 438   if (rua != NULL)
 439   {
 440     for (tmp_ans = 0; rua[tmp_ans] != NULL; tmp_ans++)
 441     {
 442       history_buffer = string_sprintf("%srua %s\n", history_buffer, rua[tmp_ans]);
 443     }
 444   }
 445   else
 446     history_buffer = string_sprintf("%srua -\n", history_buffer);
 447
 448   opendmarc_policy_fetch_pct(dmarc_pctx, &tmp_ans);
 449   history_buffer = string_sprintf("%spct %d\n", history_buffer, tmp_ans);
 450
 451   opendmarc_policy_fetch_adkim(dmarc_pctx, &tmp_ans);
 452   history_buffer = string_sprintf("%sadkim %d\n", history_buffer, tmp_ans);
 453
 454   opendmarc_policy_fetch_aspf(dmarc_pctx, &tmp_ans);
 455   history_buffer = string_sprintf("%saspf %d\n", history_buffer, tmp_ans);
 456
 457   opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
 458   history_buffer = string_sprintf("%sp %d\n", history_buffer, tmp_ans);
 459
 460   opendmarc_policy_fetch_sp(dmarc_pctx, &tmp_ans);
 461   history_buffer = string_sprintf("%ssp %d\n", history_buffer, tmp_ans);
 462
 463   history_buffer = string_sprintf("%salign_dkim %d\n", history_buffer, da);
 464   history_buffer = string_sprintf("%salign_spf %d\n", history_buffer, sa);
 465   history_buffer = string_sprintf("%saction %d\n", history_buffer, action);
 466
 467   /* Write the contents to the history file */
 468   DEBUG(D_receive)
 469     debug_printf("DMARC logging history data for opendmarc reporting%s\n",
 470                  (host_checking || running_in_test_harness) ? " (not really)" : "");
 471   if (host_checking || running_in_test_harness)
 472   {
 473     DEBUG(D_receive)
 474       debug_printf("DMARC history data for debugging:\n%s", history_buffer);
 475   }
 476   else
 477   {
 478     written_len = write_to_fd_buf(history_file_fd,
 479                                   history_buffer,
 480                                   Ustrlen(history_buffer));
 481     if (written_len == 0)
 482     {
 483       log_write(0, LOG_MAIN|LOG_PANIC, "failure to write to DMARC history file: %s",
 484                              dmarc_history_file);
 485       return DMARC_HIST_WRITE_ERR;
 486     }
 487     (void)close(history_file_fd);
 488   }
 489   return DMARC_HIST_OK;
 490 }
 491
 492 void dmarc_send_forensic_report(u_char **ruf)
 493 {
 494   int   c;
 495   uschar *recipient, *save_sender;
 496   BOOL  send_status = FALSE;
 497   error_block *eblock = NULL;
 498   FILE *message_file = NULL;
 499
 500   /* Earlier ACL does not have *required* control=dmarc_enable_forensic */
 501   if (dmarc_enable_forensic == FALSE)
 502     return;
 503
 504   if ((dmarc_policy == DMARC_POLICY_REJECT     && action == DMARC_RESULT_REJECT) ||
 505       (dmarc_policy == DMARC_POLICY_QUARANTINE && action == DMARC_RESULT_QUARANTINE) )
 506   {
 507     if (ruf != NULL)
 508     {
 509       eblock = add_to_eblock(eblock, US"Sender Domain", dmarc_used_domain);
 510       eblock = add_to_eblock(eblock, US"Sender IP Address", sender_host_address);
 511       eblock = add_to_eblock(eblock, US"Received Date", tod_stamp(tod_full));
 512       eblock = add_to_eblock(eblock, US"SPF Alignment",
 513                              (sa==DMARC_POLICY_SPF_ALIGNMENT_PASS) ?US"yes":US"no");
 514       eblock = add_to_eblock(eblock, US"DKIM Alignment",
 515                              (da==DMARC_POLICY_DKIM_ALIGNMENT_PASS)?US"yes":US"no");
 516       eblock = add_to_eblock(eblock, US"DMARC Results", dmarc_status_text);
 517       /* Set a sane default envelope sender */
 518       dsn_from = dmarc_forensic_sender ? dmarc_forensic_sender :
 519                  dsn_from ? dsn_from :
 520                  string_sprintf("do-not-reply@%s",primary_hostname);
 521       for (c = 0; ruf[c] != NULL; c++)
 522       {
 523         recipient = string_copylc(ruf[c]);
 524         if (Ustrncmp(recipient, "mailto:",7))
 525         continue;
 526         /* Move to first character past the colon */
 527         recipient += 7;
 528         DEBUG(D_receive)
 529           debug_printf("DMARC forensic report to %s%s\n", recipient,
 530                        (host_checking || running_in_test_harness) ? " (not really)" : "");
 531         if (host_checking || running_in_test_harness)
 532           continue;
 533         save_sender = sender_address;
 534         sender_address = recipient;
 535         send_status = moan_to_sender(ERRMESS_DMARC_FORENSIC, eblock,
 536                                      header_list, message_file, FALSE);
 537         sender_address = save_sender;
 538         if (send_status == FALSE)
 539           log_write(0, LOG_MAIN|LOG_PANIC, "failure to send DMARC forensic report to %s",
 540                     recipient);
 541       }
 542     }
 543   }
 544 }
 545
 546 uschar *dmarc_exim_expand_query(int what)
 547 {
 548   if (dmarc_disable_verify || !dmarc_pctx)
 549     return dmarc_exim_expand_defaults(what);
 550
 551   switch(what) {
 552     case DMARC_VERIFY_STATUS:
 553       return(dmarc_status);
 554     default:
 555       return US"";
 556   }
 557 }
 558
 559 uschar *dmarc_exim_expand_defaults(int what)
 560 {
 561   switch(what) {
 562     case DMARC_VERIFY_STATUS:
 563       return (dmarc_disable_verify) ?
 564               US"off" :
 565               US"none";
 566     default:
 567       return US"";
 568   }
 569 }
 570
 571 uschar *dmarc_auth_results_header(header_line *from_header, uschar *hostname)
 572 {
 573   uschar *hdr_tmp    = US"";
 574
 575   /* Allow a server hostname to be passed to this function, but is
 576    * currently unused */
 577   if (hostname == NULL)
 578     hostname = primary_hostname;
 579   hdr_tmp = string_sprintf("%s %s;", DMARC_AR_HEADER, hostname);
 580
 581 #if 0
 582   /* I don't think this belongs here, but left it here commented out
 583    * because it was a lot of work to get working right. */
 584 #ifdef EXPERIMENTAL_SPF
 585   if (spf_response != NULL) {
 586     uschar *dmarc_ar_spf = US"";
 587     int sr               = 0;
 588     sr = spf_response->result;
 589     dmarc_ar_spf = (sr == SPF_RESULT_NEUTRAL)  ? US"neutral" :
 590                    (sr == SPF_RESULT_PASS)     ? US"pass" :
 591                    (sr == SPF_RESULT_FAIL)     ? US"fail" :
 592                    (sr == SPF_RESULT_SOFTFAIL) ? US"softfail" :
 593                    US"none";
 594     hdr_tmp = string_sprintf("%s spf=%s (%s) smtp.mail=%s;",
 595                              hdr_tmp, dmarc_ar_spf_result,
 596                              spf_response->header_comment,
 597                              expand_string(US"$sender_address") );
 598   }
 599 #endif
 600 #endif
 601   hdr_tmp = string_sprintf("%s dmarc=%s",
 602                            hdr_tmp, dmarc_pass_fail);
 603   if (header_from_sender)
 604     hdr_tmp = string_sprintf("%s header.from=%s",
 605                              hdr_tmp, header_from_sender);
 606   return hdr_tmp;
 607 }
 608
 609 #endif
 610
 611 // vim:sw=2 expandtab