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