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 == FALSE )
 127   {
 128     is_ipv6 = string_is_ip_address(sender_host_address, netmask);
 129     is_ipv6 = (is_ipv6 == 6) ? TRUE :
 130               (is_ipv6 == 4) ? FALSE : FALSE;
 131     dmarc_pctx = opendmarc_policy_connect_init(sender_host_address, is_ipv6);
 132     if (dmarc_pctx == NULL )
 133     {
 134       log_write(0, LOG_MAIN|LOG_PANIC, "DMARC failure creating policy context: ip=%s",
 135                                        sender_host_address);
 136       dmarc_abort = TRUE;
 137     }
 138   }
 139
 140   return OK;
 141 }
 142
 143
 144 /* dmarc_store_data stores the header data so that subsequent
 145  * dmarc_process can access the data */
 146
 147 int dmarc_store_data(header_line *hdr) {
 148   /* No debug output because would change every test debug output */
 149   if (dmarc_disable_verify != TRUE)
 150     from_header = hdr;
 151   return OK;
 152 }
 153
 154
 155 /* dmarc_process adds the envelope sender address to the existing
 156    context (if any), retrieves the result, sets up expansion
 157    strings and evaluates the condition outcome. */
 158
 159 int dmarc_process() {
 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 == TRUE)
 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 == NULL || dmarc_abort == TRUE)
 181     dmarc_abort = TRUE;
 182   else
 183   {
 184     /* I strongly encourage anybody who can make this better to contact me directly!
 185      * <cannonball> Is this an insane way to extract the email address from the From: header?
 186      * <jgh_hm> it's sure a horrid layer-crossing....
 187      * <cannonball> I'm not denying that :-/
 188      * <jgh_hm> there may well be no better though
 189      */
 190     header_from_sender = expand_string(
 191            string_sprintf("${domain:${extract{1}{:}{${addresses:\\N%s\\N}}}}",
 192                           from_header->text) );
 193     /* The opendmarc library extracts the domain from the email address, but
 194      * only try to store it if it's not empty.  Otherwise, skip out of DMARC. */
 195     if ((header_from_sender == NULL) || (strcmp( CCS header_from_sender, "") == 0))
 196       dmarc_abort = TRUE;
 197     libdm_status = (dmarc_abort == TRUE) ?
 198       DMARC_PARSE_OKAY :
 199       opendmarc_policy_store_from_domain(dmarc_pctx, header_from_sender);
 200     if (libdm_status != DMARC_PARSE_OKAY)
 201     {
 202       log_write(0, LOG_MAIN|LOG_PANIC,
 203                 "failure to store header From: in DMARC: %s, header was '%s'",
 204                 opendmarc_policy_status_to_str(libdm_status), from_header->text);
 205       dmarc_abort = TRUE;
 206     }
 207   }
 208
 209   /* Skip DMARC if connection is SMTP Auth. Temporarily, admin should
 210    * instead do this in the ACLs.  */
 211   if (dmarc_abort == FALSE && sender_host_authenticated == NULL)
 212   {
 213     /* Use the envelope sender domain for this part of DMARC */
 214     spf_sender_domain = expand_string(US"$sender_address_domain");
 215     if ( spf_response == NULL )
 216     {
 217       /* No spf data means null envelope sender so generate a domain name
 218        * from the sender_helo_name  */
 219       if (spf_sender_domain == NULL)
 220       {
 221         spf_sender_domain = sender_helo_name;
 222         log_write(0, LOG_MAIN, "DMARC using synthesized SPF sender domain = %s\n",
 223                                spf_sender_domain);
 224         DEBUG(D_receive)
 225           debug_printf("DMARC using synthesized SPF sender domain = %s\n", spf_sender_domain);
 226       }
 227       dmarc_spf_result = DMARC_POLICY_SPF_OUTCOME_NONE;
 228       dmarc_spf_ares_result = ARES_RESULT_UNKNOWN;
 229       origin = DMARC_POLICY_SPF_ORIGIN_HELO;
 230       spf_human_readable = US"";
 231     }
 232     else
 233     {
 234       sr = spf_response->result;
 235       dmarc_spf_result = (sr == SPF_RESULT_NEUTRAL)  ? DMARC_POLICY_SPF_OUTCOME_NONE :
 236                          (sr == SPF_RESULT_PASS)     ? DMARC_POLICY_SPF_OUTCOME_PASS :
 237                          (sr == SPF_RESULT_FAIL)     ? DMARC_POLICY_SPF_OUTCOME_FAIL :
 238                          (sr == SPF_RESULT_SOFTFAIL) ? DMARC_POLICY_SPF_OUTCOME_TMPFAIL :
 239                          DMARC_POLICY_SPF_OUTCOME_NONE;
 240       dmarc_spf_ares_result = (sr == SPF_RESULT_NEUTRAL)   ? ARES_RESULT_NEUTRAL :
 241                               (sr == SPF_RESULT_PASS)      ? ARES_RESULT_PASS :
 242                               (sr == SPF_RESULT_FAIL)      ? ARES_RESULT_FAIL :
 243                               (sr == SPF_RESULT_SOFTFAIL)  ? ARES_RESULT_SOFTFAIL :
 244                               (sr == SPF_RESULT_NONE)      ? ARES_RESULT_NONE :
 245                               (sr == SPF_RESULT_TEMPERROR) ? ARES_RESULT_TEMPERROR :
 246                               (sr == SPF_RESULT_PERMERROR) ? ARES_RESULT_PERMERROR :
 247                               ARES_RESULT_UNKNOWN;
 248       origin = DMARC_POLICY_SPF_ORIGIN_MAILFROM;
 249       spf_human_readable = (uschar *)spf_response->header_comment;
 250       DEBUG(D_receive)
 251         debug_printf("DMARC using SPF sender domain = %s\n", spf_sender_domain);
 252     }
 253     if (strcmp( CCS spf_sender_domain, "") == 0)
 254       dmarc_abort = TRUE;
 255     if (dmarc_abort == FALSE)
 256     {
 257       libdm_status = opendmarc_policy_store_spf(dmarc_pctx, spf_sender_domain,
 258                                                 dmarc_spf_result, origin, spf_human_readable);
 259       if (libdm_status != DMARC_PARSE_OKAY)
 260         log_write(0, LOG_MAIN|LOG_PANIC, "failure to store spf for DMARC: %s",
 261                              opendmarc_policy_status_to_str(libdm_status));
 262     }
 263
 264     /* Now we cycle through the dkim signature results and put into
 265      * the opendmarc context, further building the DMARC reply.  */
 266     sig = dkim_signatures;
 267     dkim_history_buffer = US"";
 268     while (sig != NULL)
 269     {
 270       int dkim_result, dkim_ares_result, vs, ves;
 271       vs  = sig->verify_status;
 272       ves = sig->verify_ext_status;
 273       dkim_result = ( vs == PDKIM_VERIFY_PASS ) ? DMARC_POLICY_DKIM_OUTCOME_PASS :
 274                     ( vs == PDKIM_VERIFY_FAIL ) ? DMARC_POLICY_DKIM_OUTCOME_FAIL :
 275                     ( vs == PDKIM_VERIFY_INVALID ) ? DMARC_POLICY_DKIM_OUTCOME_TMPFAIL :
 276                     DMARC_POLICY_DKIM_OUTCOME_NONE;
 277       libdm_status = opendmarc_policy_store_dkim(dmarc_pctx, (uschar *)sig->domain,
 278                                                  dkim_result, US"");
 279       DEBUG(D_receive)
 280         debug_printf("DMARC adding DKIM sender domain = %s\n", sig->domain);
 281       if (libdm_status != DMARC_PARSE_OKAY)
 282         log_write(0, LOG_MAIN|LOG_PANIC, "failure to store dkim (%s) for DMARC: %s",
 283                   sig->domain, opendmarc_policy_status_to_str(libdm_status));
 284
 285       dkim_ares_result = ( vs == PDKIM_VERIFY_PASS )    ? ARES_RESULT_PASS :
 286                          ( vs == PDKIM_VERIFY_FAIL )    ? ARES_RESULT_FAIL :
 287                          ( vs == PDKIM_VERIFY_NONE )    ? ARES_RESULT_NONE :
 288                          ( vs == PDKIM_VERIFY_INVALID ) ?
 289                            ( ves == PDKIM_VERIFY_INVALID_PUBKEY_UNAVAILABLE ? ARES_RESULT_PERMERROR :
 290                              ves == PDKIM_VERIFY_INVALID_BUFFER_SIZE        ? ARES_RESULT_PERMERROR :
 291                              ves == PDKIM_VERIFY_INVALID_PUBKEY_PARSING     ? ARES_RESULT_PERMERROR :
 292                              ARES_RESULT_UNKNOWN ) :
 293                           ARES_RESULT_UNKNOWN;
 294       dkim_history_buffer = string_sprintf("%sdkim %s %d\n", dkim_history_buffer,
 295                                            sig->domain, dkim_ares_result);
 296       sig = sig->next;
 297     }
 298     libdm_status = opendmarc_policy_query_dmarc(dmarc_pctx, US"");
 299     switch (libdm_status)
 300     {
 301       case DMARC_DNS_ERROR_NXDOMAIN:
 302       case DMARC_DNS_ERROR_NO_RECORD:
 303         DEBUG(D_receive)
 304           debug_printf("DMARC no record found for %s\n", header_from_sender);
 305         has_dmarc_record = FALSE;
 306         break;
 307       case DMARC_PARSE_OKAY:
 308         DEBUG(D_receive)
 309           debug_printf("DMARC record found for %s\n", header_from_sender);
 310         break;
 311       case DMARC_PARSE_ERROR_BAD_VALUE:
 312         DEBUG(D_receive)
 313           debug_printf("DMARC record parse error for %s\n", header_from_sender);
 314         has_dmarc_record = FALSE;
 315         break;
 316       default:
 317         /* everything else, skip dmarc */
 318         DEBUG(D_receive)
 319           debug_printf("DMARC skipping (%d), unsure what to do with %s",
 320                         libdm_status, from_header->text);
 321         has_dmarc_record = FALSE;
 322         break;
 323     }
 324
 325   /* Store the policy string in an expandable variable. */
 326     libdm_status = opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
 327     for (c=0; dmarc_policy_description[c].name != NULL; c++) {
 328       if (tmp_ans == dmarc_policy_description[c].value) {
 329         dmarc_domain_policy = string_sprintf("%s",dmarc_policy_description[c].name);
 330         break;
 331       }
 332     }
 333
 334     /* Can't use exim's string manipulation functions so allocate memory
 335      * for libopendmarc using its max hostname length definition. */
 336     uschar *dmarc_domain = (uschar *)calloc(DMARC_MAXHOSTNAMELEN, sizeof(uschar));
 337     libdm_status = opendmarc_policy_fetch_utilized_domain(dmarc_pctx, dmarc_domain,
 338                                                   DMARC_MAXHOSTNAMELEN-1);
 339     dmarc_used_domain = string_copy(dmarc_domain);
 340     free(dmarc_domain);
 341     if (libdm_status != DMARC_PARSE_OKAY)
 342     {
 343       log_write(0, LOG_MAIN|LOG_PANIC, "failure to read domainname used for DMARC lookup: %s",
 344                                        opendmarc_policy_status_to_str(libdm_status));
 345     }
 346     libdm_status = opendmarc_get_policy_to_enforce(dmarc_pctx);
 347     dmarc_policy = libdm_status;
 348     switch(libdm_status)
 349     {
 350       case DMARC_POLICY_ABSENT:     /* No DMARC record found */
 351         dmarc_status = US"norecord";
 352         dmarc_pass_fail = US"none";
 353         dmarc_status_text = US"No DMARC record";
 354         action = DMARC_RESULT_ACCEPT;
 355         break;
 356       case DMARC_FROM_DOMAIN_ABSENT:    /* No From: domain */
 357         dmarc_status = US"nofrom";
 358         dmarc_pass_fail = US"temperror";
 359         dmarc_status_text = US"No From: domain found";
 360         action = DMARC_RESULT_ACCEPT;
 361         break;
 362       case DMARC_POLICY_NONE:       /* Accept and report */
 363         dmarc_status = US"none";
 364         dmarc_pass_fail = US"none";
 365         dmarc_status_text = US"None, Accept";
 366         action = DMARC_RESULT_ACCEPT;
 367         break;
 368       case DMARC_POLICY_PASS:       /* Explicit accept */
 369         dmarc_status = US"accept";
 370         dmarc_pass_fail = US"pass";
 371         dmarc_status_text = US"Accept";
 372         action = DMARC_RESULT_ACCEPT;
 373         break;
 374       case DMARC_POLICY_REJECT:       /* Explicit reject */
 375         dmarc_status = US"reject";
 376         dmarc_pass_fail = US"fail";
 377         dmarc_status_text = US"Reject";
 378         action = DMARC_RESULT_REJECT;
 379         break;
 380       case DMARC_POLICY_QUARANTINE:       /* Explicit quarantine */
 381         dmarc_status = US"quarantine";
 382         dmarc_pass_fail = US"fail";
 383         dmarc_status_text = US"Quarantine";
 384         action = DMARC_RESULT_QUARANTINE;
 385         break;
 386       default:
 387         dmarc_status = US"temperror";
 388         dmarc_pass_fail = US"temperror";
 389         dmarc_status_text = US"Internal Policy Error";
 390         action = DMARC_RESULT_TEMPFAIL;
 391         break;
 392     }
 393
 394     libdm_status = opendmarc_policy_fetch_alignment(dmarc_pctx, &da, &sa);
 395     if (libdm_status != DMARC_PARSE_OKAY)
 396     {
 397       log_write(0, LOG_MAIN|LOG_PANIC, "failure to read DMARC alignment: %s",
 398                                        opendmarc_policy_status_to_str(libdm_status));
 399     }
 400
 401     if (has_dmarc_record == TRUE)
 402     {
 403       log_write(0, LOG_MAIN, "DMARC results: spf_domain=%s dmarc_domain=%s "
 404                              "spf_align=%s dkim_align=%s enforcement='%s'",
 405                              spf_sender_domain, dmarc_used_domain,
 406                              (sa==DMARC_POLICY_SPF_ALIGNMENT_PASS) ?"yes":"no",
 407                              (da==DMARC_POLICY_DKIM_ALIGNMENT_PASS)?"yes":"no",
 408                              dmarc_status_text);
 409       history_file_status = dmarc_write_history_file();
 410       /* Now get the forensic reporting addresses, if any */
 411       ruf = opendmarc_policy_fetch_ruf(dmarc_pctx, NULL, 0, 1);
 412       dmarc_send_forensic_report(ruf);
 413     }
 414   }
 415
 416   /* set some global variables here */
 417   dmarc_ar_header = dmarc_auth_results_header(from_header, NULL);
 418
 419   /* shut down libopendmarc */
 420   if ( dmarc_pctx != NULL )
 421     (void) opendmarc_policy_connect_shutdown(dmarc_pctx);
 422   if ( dmarc_disable_verify == FALSE )
 423     (void) opendmarc_policy_library_shutdown(&dmarc_ctx);
 424
 425   return OK;
 426 }
 427
 428 int dmarc_write_history_file()
 429 {
 430   int history_file_fd;
 431   ssize_t written_len;
 432   int tmp_ans;
 433   u_char **rua; /* aggregate report addressees */
 434   uschar *history_buffer = NULL;
 435
 436   if (dmarc_history_file == NULL)
 437     return DMARC_HIST_DISABLED;
 438   history_file_fd = log_create(dmarc_history_file);
 439
 440   if (history_file_fd < 0)
 441   {
 442     log_write(0, LOG_MAIN|LOG_PANIC, "failure to create DMARC history file: %s",
 443                              dmarc_history_file);
 444     return DMARC_HIST_FILE_ERR;
 445   }
 446
 447   /* Generate the contents of the history file */
 448   history_buffer = string_sprintf("job %s\n", message_id);
 449   history_buffer = string_sprintf("%sreporter %s\n", history_buffer, primary_hostname);
 450   history_buffer = string_sprintf("%sreceived %ld\n", history_buffer, time(NULL));
 451   history_buffer = string_sprintf("%sipaddr %s\n", history_buffer, sender_host_address);
 452   history_buffer = string_sprintf("%sfrom %s\n", history_buffer, header_from_sender);
 453   history_buffer = string_sprintf("%smfrom %s\n", history_buffer,
 454                      expand_string(US"$sender_address_domain"));
 455
 456   if (spf_response != NULL)
 457     history_buffer = string_sprintf("%sspf %d\n", history_buffer, dmarc_spf_ares_result);
 458     /* history_buffer = string_sprintf("%sspf -1\n", history_buffer); */
 459
 460   history_buffer = string_sprintf("%s%s", history_buffer, dkim_history_buffer);
 461   history_buffer = string_sprintf("%spdomain %s\n", history_buffer, dmarc_used_domain);
 462   history_buffer = string_sprintf("%spolicy %d\n", history_buffer, dmarc_policy);
 463
 464   rua = opendmarc_policy_fetch_rua(dmarc_pctx, NULL, 0, 1);
 465   if (rua != NULL)
 466   {
 467     for (tmp_ans = 0; rua[tmp_ans] != NULL; tmp_ans++)
 468     {
 469       history_buffer = string_sprintf("%srua %s\n", history_buffer, rua[tmp_ans]);
 470     }
 471   }
 472   else
 473     history_buffer = string_sprintf("%srua -\n", history_buffer);
 474
 475   opendmarc_policy_fetch_pct(dmarc_pctx, &tmp_ans);
 476   history_buffer = string_sprintf("%spct %d\n", history_buffer, tmp_ans);
 477
 478   opendmarc_policy_fetch_adkim(dmarc_pctx, &tmp_ans);
 479   history_buffer = string_sprintf("%sadkim %d\n", history_buffer, tmp_ans);
 480
 481   opendmarc_policy_fetch_aspf(dmarc_pctx, &tmp_ans);
 482   history_buffer = string_sprintf("%saspf %d\n", history_buffer, tmp_ans);
 483
 484   opendmarc_policy_fetch_p(dmarc_pctx, &tmp_ans);
 485   history_buffer = string_sprintf("%sp %d\n", history_buffer, tmp_ans);
 486
 487   opendmarc_policy_fetch_sp(dmarc_pctx, &tmp_ans);
 488   history_buffer = string_sprintf("%ssp %d\n", history_buffer, tmp_ans);
 489
 490   history_buffer = string_sprintf("%salign_dkim %d\n", history_buffer, da);
 491   history_buffer = string_sprintf("%salign_spf %d\n", history_buffer, sa);
 492   history_buffer = string_sprintf("%saction %d\n", history_buffer, action);
 493
 494   /* Write the contents to the history file */
 495   DEBUG(D_receive)
 496     debug_printf("DMARC logging history data for opendmarc reporting%s\n",
 497                  (host_checking || running_in_test_harness) ? " (not really)" : "");
 498   if (host_checking || running_in_test_harness)
 499   {
 500     DEBUG(D_receive)
 501       debug_printf("DMARC history data for debugging:\n%s", history_buffer);
 502   }
 503   else
 504   {
 505     written_len = write_to_fd_buf(history_file_fd,
 506                                   history_buffer,
 507                                   Ustrlen(history_buffer));
 508     if (written_len == 0)
 509     {
 510       log_write(0, LOG_MAIN|LOG_PANIC, "failure to write to DMARC history file: %s",
 511                              dmarc_history_file);
 512       return DMARC_HIST_WRITE_ERR;
 513     }
 514     (void)close(history_file_fd);
 515   }
 516   return DMARC_HIST_OK;
 517 }
 518
 519 void dmarc_send_forensic_report(u_char **ruf)
 520 {
 521   int   c;
 522   uschar *recipient, *save_sender;
 523   BOOL  send_status = FALSE;
 524   error_block *eblock = NULL;
 525   FILE *message_file = NULL;
 526
 527   /* Earlier ACL does not have *required* control=dmarc_enable_forensic */
 528   if (dmarc_enable_forensic == FALSE)
 529     return;
 530
 531   if ((dmarc_policy == DMARC_POLICY_REJECT     && action == DMARC_RESULT_REJECT) ||
 532       (dmarc_policy == DMARC_POLICY_QUARANTINE && action == DMARC_RESULT_QUARANTINE) )
 533   {
 534     if (ruf != NULL)
 535     {
 536       eblock = add_to_eblock(eblock, US"Sender Domain", dmarc_used_domain);
 537       eblock = add_to_eblock(eblock, US"Sender IP Address", sender_host_address);
 538       eblock = add_to_eblock(eblock, US"Received Date", tod_stamp(tod_full));
 539       eblock = add_to_eblock(eblock, US"SPF Alignment",
 540                              (sa==DMARC_POLICY_SPF_ALIGNMENT_PASS) ?US"yes":US"no");
 541       eblock = add_to_eblock(eblock, US"DKIM Alignment",
 542                              (da==DMARC_POLICY_DKIM_ALIGNMENT_PASS)?US"yes":US"no");
 543       eblock = add_to_eblock(eblock, US"DMARC Results", dmarc_status_text);
 544       /* Set a sane default envelope sender */
 545       dsn_from = dmarc_forensic_sender ? dmarc_forensic_sender :
 546                  dsn_from ? dsn_from :
 547                  string_sprintf("do-not-reply@%s",primary_hostname);
 548       for (c = 0; ruf[c] != NULL; c++)
 549       {
 550         recipient = string_copylc(ruf[c]);
 551         if (Ustrncmp(recipient, "mailto:",7))
 552         continue;
 553         /* Move to first character past the colon */
 554         recipient += 7;
 555         DEBUG(D_receive)
 556           debug_printf("DMARC forensic report to %s%s\n", recipient,
 557                        (host_checking || running_in_test_harness) ? " (not really)" : "");
 558         if (host_checking || running_in_test_harness)
 559           continue;
 560         save_sender = sender_address;
 561         sender_address = recipient;
 562         send_status = moan_to_sender(ERRMESS_DMARC_FORENSIC, eblock,
 563                                      header_list, message_file, FALSE);
 564         sender_address = save_sender;
 565         if (send_status == FALSE)
 566           log_write(0, LOG_MAIN|LOG_PANIC, "failure to send DMARC forensic report to %s",
 567                     recipient);
 568       }
 569     }
 570   }
 571 }
 572
 573 uschar *dmarc_exim_expand_query(int what)
 574 {
 575   if (dmarc_disable_verify || !dmarc_pctx)
 576     return dmarc_exim_expand_defaults(what);
 577
 578   switch(what) {
 579     case DMARC_VERIFY_STATUS:
 580       return(dmarc_status);
 581     default:
 582       return US"";
 583   }
 584 }
 585
 586 uschar *dmarc_exim_expand_defaults(int what)
 587 {
 588   switch(what) {
 589     case DMARC_VERIFY_STATUS:
 590       return (dmarc_disable_verify) ?
 591               US"off" :
 592               US"none";
 593     default:
 594       return US"";
 595   }
 596 }
 597
 598 uschar *dmarc_auth_results_header(header_line *from_header, uschar *hostname)
 599 {
 600   uschar *hdr_tmp    = US"";
 601
 602   /* Allow a server hostname to be passed to this function, but is
 603    * currently unused */
 604   if (hostname == NULL)
 605     hostname = primary_hostname;
 606   hdr_tmp = string_sprintf("%s %s;", DMARC_AR_HEADER, hostname);
 607
 608 #if 0
 609   /* I don't think this belongs here, but left it here commented out
 610    * because it was a lot of work to get working right. */
 611   if (spf_response != NULL) {
 612     uschar *dmarc_ar_spf = US"";
 613     int sr               = 0;
 614     sr = spf_response->result;
 615     dmarc_ar_spf = (sr == SPF_RESULT_NEUTRAL)  ? US"neutral" :
 616                    (sr == SPF_RESULT_PASS)     ? US"pass" :
 617                    (sr == SPF_RESULT_FAIL)     ? US"fail" :
 618                    (sr == SPF_RESULT_SOFTFAIL) ? US"softfail" :
 619                    US"none";
 620     hdr_tmp = string_sprintf("%s spf=%s (%s) smtp.mail=%s;",
 621                              hdr_tmp, dmarc_ar_spf_result,
 622                              spf_response->header_comment,
 623                              expand_string(US"$sender_address") );
 624   }
 625 #endif
 626   hdr_tmp = string_sprintf("%s dmarc=%s",
 627                            hdr_tmp, dmarc_pass_fail);
 628   if (header_from_sender)
 629     hdr_tmp = string_sprintf("%s header.from=%s",
 630                              hdr_tmp, header_from_sender);
 631   return hdr_tmp;
 632 }
 633
 634 #endif /* EXPERIMENTAL_SPF */
 635 #endif /* EXPERIMENTAL_DMARC */