| 1 | /* $Cambridge: exim/src/src/acl.c,v 1.42 2005/07/23 20:46:42 tom Exp $ */ |
| 2 | |
| 3 | /************************************************* |
| 4 | * Exim - an Internet mail transport agent * |
| 5 | *************************************************/ |
| 6 | |
| 7 | /* Copyright (c) University of Cambridge 1995 - 2005 */ |
| 8 | /* See the file NOTICE for conditions of use and distribution. */ |
| 9 | |
| 10 | /* Code for handling Access Control Lists (ACLs) */ |
| 11 | |
| 12 | #include "exim.h" |
| 13 | |
| 14 | |
| 15 | /* Default callout timeout */ |
| 16 | |
| 17 | #define CALLOUT_TIMEOUT_DEFAULT 30 |
| 18 | |
| 19 | /* ACL verb codes - keep in step with the table of verbs that follows */ |
| 20 | |
| 21 | enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE, |
| 22 | ACL_WARN }; |
| 23 | |
| 24 | /* ACL verbs */ |
| 25 | |
| 26 | static uschar *verbs[] = |
| 27 | { US"accept", US"defer", US"deny", US"discard", US"drop", US"require", |
| 28 | US"warn" }; |
| 29 | |
| 30 | /* For each verb, the condition for which "message" is used */ |
| 31 | |
| 32 | static int msgcond[] = { FAIL, OK, OK, FAIL, OK, FAIL, OK }; |
| 33 | |
| 34 | /* ACL condition and modifier codes - keep in step with the table that |
| 35 | follows. */ |
| 36 | |
| 37 | enum { ACLC_ACL, ACLC_AUTHENTICATED, |
| 38 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 39 | ACLC_BMI_OPTIN, |
| 40 | #endif |
| 41 | ACLC_CONDITION, ACLC_CONTROL, |
| 42 | #ifdef WITH_CONTENT_SCAN |
| 43 | ACLC_DECODE, |
| 44 | #endif |
| 45 | ACLC_DELAY, |
| 46 | #ifdef WITH_OLD_DEMIME |
| 47 | ACLC_DEMIME, |
| 48 | #endif |
| 49 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 50 | ACLC_DK_DOMAIN_SOURCE, |
| 51 | ACLC_DK_POLICY, |
| 52 | ACLC_DK_SENDER_DOMAINS, |
| 53 | ACLC_DK_SENDER_LOCAL_PARTS, |
| 54 | ACLC_DK_SENDERS, |
| 55 | ACLC_DK_STATUS, |
| 56 | #endif |
| 57 | ACLC_DNSLISTS, ACLC_DOMAINS, ACLC_ENCRYPTED, ACLC_ENDPASS, |
| 58 | ACLC_HOSTS, ACLC_LOCAL_PARTS, ACLC_LOG_MESSAGE, ACLC_LOGWRITE, |
| 59 | #ifdef WITH_CONTENT_SCAN |
| 60 | ACLC_MALWARE, |
| 61 | #endif |
| 62 | ACLC_MESSAGE, |
| 63 | #ifdef WITH_CONTENT_SCAN |
| 64 | ACLC_MIME_REGEX, |
| 65 | #endif |
| 66 | ACLC_RATELIMIT, |
| 67 | ACLC_RECIPIENTS, |
| 68 | #ifdef WITH_CONTENT_SCAN |
| 69 | ACLC_REGEX, |
| 70 | #endif |
| 71 | ACLC_SENDER_DOMAINS, ACLC_SENDERS, ACLC_SET, |
| 72 | #ifdef WITH_CONTENT_SCAN |
| 73 | ACLC_SPAM, |
| 74 | #endif |
| 75 | #ifdef EXPERIMENTAL_SPF |
| 76 | ACLC_SPF, |
| 77 | #endif |
| 78 | ACLC_VERIFY }; |
| 79 | |
| 80 | /* ACL conditions/modifiers: "delay", "control", "endpass", "message", |
| 81 | "log_message", "logwrite", and "set" are modifiers that look like conditions |
| 82 | but always return TRUE. They are used for their side effects. */ |
| 83 | |
| 84 | static uschar *conditions[] = { |
| 85 | US"acl", |
| 86 | US"authenticated", |
| 87 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 88 | US"bmi_optin", |
| 89 | #endif |
| 90 | US"condition", |
| 91 | US"control", |
| 92 | #ifdef WITH_CONTENT_SCAN |
| 93 | US"decode", |
| 94 | #endif |
| 95 | US"delay", |
| 96 | #ifdef WITH_OLD_DEMIME |
| 97 | US"demime", |
| 98 | #endif |
| 99 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 100 | US"dk_domain_source", |
| 101 | US"dk_policy", |
| 102 | US"dk_sender_domains", |
| 103 | US"dk_sender_local_parts", |
| 104 | US"dk_senders", |
| 105 | US"dk_status", |
| 106 | #endif |
| 107 | US"dnslists", US"domains", US"encrypted", |
| 108 | US"endpass", US"hosts", US"local_parts", US"log_message", US"logwrite", |
| 109 | #ifdef WITH_CONTENT_SCAN |
| 110 | US"malware", |
| 111 | #endif |
| 112 | US"message", |
| 113 | #ifdef WITH_CONTENT_SCAN |
| 114 | US"mime_regex", |
| 115 | #endif |
| 116 | US"ratelimit", |
| 117 | US"recipients", |
| 118 | #ifdef WITH_CONTENT_SCAN |
| 119 | US"regex", |
| 120 | #endif |
| 121 | US"sender_domains", US"senders", US"set", |
| 122 | #ifdef WITH_CONTENT_SCAN |
| 123 | US"spam", |
| 124 | #endif |
| 125 | #ifdef EXPERIMENTAL_SPF |
| 126 | US"spf", |
| 127 | #endif |
| 128 | US"verify" }; |
| 129 | |
| 130 | |
| 131 | /* Return values from decode_control(); keep in step with the table of names |
| 132 | that follows! */ |
| 133 | |
| 134 | enum { |
| 135 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 136 | CONTROL_BMI_RUN, |
| 137 | #endif |
| 138 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 139 | CONTROL_DK_VERIFY, |
| 140 | #endif |
| 141 | CONTROL_ERROR, CONTROL_CASEFUL_LOCAL_PART, CONTROL_CASELOWER_LOCAL_PART, |
| 142 | CONTROL_ENFORCE_SYNC, CONTROL_NO_ENFORCE_SYNC, CONTROL_FREEZE, |
| 143 | CONTROL_QUEUE_ONLY, CONTROL_SUBMISSION, |
| 144 | #ifdef WITH_CONTENT_SCAN |
| 145 | CONTROL_NO_MBOX_UNSPOOL, |
| 146 | #endif |
| 147 | CONTROL_FAKEDEFER, CONTROL_FAKEREJECT, CONTROL_NO_MULTILINE }; |
| 148 | |
| 149 | /* ACL control names; keep in step with the table above! */ |
| 150 | |
| 151 | static uschar *controls[] = { |
| 152 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 153 | US"bmi_run", |
| 154 | #endif |
| 155 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 156 | US"dk_verify", |
| 157 | #endif |
| 158 | US"error", US"caseful_local_part", |
| 159 | US"caselower_local_part", US"enforce_sync", US"no_enforce_sync", US"freeze", |
| 160 | US"queue_only", US"submission", |
| 161 | #ifdef WITH_CONTENT_SCAN |
| 162 | US"no_mbox_unspool", |
| 163 | #endif |
| 164 | US"no_multiline"}; |
| 165 | |
| 166 | /* Flags to indicate for which conditions /modifiers a string expansion is done |
| 167 | at the outer level. In the other cases, expansion already occurs in the |
| 168 | checking functions. */ |
| 169 | |
| 170 | static uschar cond_expand_at_top[] = { |
| 171 | TRUE, /* acl */ |
| 172 | FALSE, /* authenticated */ |
| 173 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 174 | TRUE, /* bmi_optin */ |
| 175 | #endif |
| 176 | TRUE, /* condition */ |
| 177 | TRUE, /* control */ |
| 178 | #ifdef WITH_CONTENT_SCAN |
| 179 | TRUE, /* decode */ |
| 180 | #endif |
| 181 | TRUE, /* delay */ |
| 182 | #ifdef WITH_OLD_DEMIME |
| 183 | TRUE, /* demime */ |
| 184 | #endif |
| 185 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 186 | TRUE, /* dk_domain_source */ |
| 187 | TRUE, /* dk_policy */ |
| 188 | TRUE, /* dk_sender_domains */ |
| 189 | TRUE, /* dk_sender_local_parts */ |
| 190 | TRUE, /* dk_senders */ |
| 191 | TRUE, /* dk_status */ |
| 192 | #endif |
| 193 | TRUE, /* dnslists */ |
| 194 | FALSE, /* domains */ |
| 195 | FALSE, /* encrypted */ |
| 196 | TRUE, /* endpass */ |
| 197 | FALSE, /* hosts */ |
| 198 | FALSE, /* local_parts */ |
| 199 | TRUE, /* log_message */ |
| 200 | TRUE, /* logwrite */ |
| 201 | #ifdef WITH_CONTENT_SCAN |
| 202 | TRUE, /* malware */ |
| 203 | #endif |
| 204 | TRUE, /* message */ |
| 205 | #ifdef WITH_CONTENT_SCAN |
| 206 | TRUE, /* mime_regex */ |
| 207 | #endif |
| 208 | TRUE, /* ratelimit */ |
| 209 | FALSE, /* recipients */ |
| 210 | #ifdef WITH_CONTENT_SCAN |
| 211 | TRUE, /* regex */ |
| 212 | #endif |
| 213 | FALSE, /* sender_domains */ |
| 214 | FALSE, /* senders */ |
| 215 | TRUE, /* set */ |
| 216 | #ifdef WITH_CONTENT_SCAN |
| 217 | TRUE, /* spam */ |
| 218 | #endif |
| 219 | #ifdef EXPERIMENTAL_SPF |
| 220 | TRUE, /* spf */ |
| 221 | #endif |
| 222 | TRUE /* verify */ |
| 223 | }; |
| 224 | |
| 225 | /* Flags to identify the modifiers */ |
| 226 | |
| 227 | static uschar cond_modifiers[] = { |
| 228 | FALSE, /* acl */ |
| 229 | FALSE, /* authenticated */ |
| 230 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 231 | TRUE, /* bmi_optin */ |
| 232 | #endif |
| 233 | FALSE, /* condition */ |
| 234 | TRUE, /* control */ |
| 235 | #ifdef WITH_CONTENT_SCAN |
| 236 | FALSE, /* decode */ |
| 237 | #endif |
| 238 | TRUE, /* delay */ |
| 239 | #ifdef WITH_OLD_DEMIME |
| 240 | FALSE, /* demime */ |
| 241 | #endif |
| 242 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 243 | FALSE, /* dk_domain_source */ |
| 244 | FALSE, /* dk_policy */ |
| 245 | FALSE, /* dk_sender_domains */ |
| 246 | FALSE, /* dk_sender_local_parts */ |
| 247 | FALSE, /* dk_senders */ |
| 248 | FALSE, /* dk_status */ |
| 249 | #endif |
| 250 | FALSE, /* dnslists */ |
| 251 | FALSE, /* domains */ |
| 252 | FALSE, /* encrypted */ |
| 253 | TRUE, /* endpass */ |
| 254 | FALSE, /* hosts */ |
| 255 | FALSE, /* local_parts */ |
| 256 | TRUE, /* log_message */ |
| 257 | TRUE, /* logwrite */ |
| 258 | #ifdef WITH_CONTENT_SCAN |
| 259 | FALSE, /* malware */ |
| 260 | #endif |
| 261 | TRUE, /* message */ |
| 262 | #ifdef WITH_CONTENT_SCAN |
| 263 | FALSE, /* mime_regex */ |
| 264 | #endif |
| 265 | FALSE, /* ratelimit */ |
| 266 | FALSE, /* recipients */ |
| 267 | #ifdef WITH_CONTENT_SCAN |
| 268 | FALSE, /* regex */ |
| 269 | #endif |
| 270 | FALSE, /* sender_domains */ |
| 271 | FALSE, /* senders */ |
| 272 | TRUE, /* set */ |
| 273 | #ifdef WITH_CONTENT_SCAN |
| 274 | FALSE, /* spam */ |
| 275 | #endif |
| 276 | #ifdef EXPERIMENTAL_SPF |
| 277 | FALSE, /* spf */ |
| 278 | #endif |
| 279 | FALSE /* verify */ |
| 280 | }; |
| 281 | |
| 282 | /* Bit map vector of which conditions are not allowed at certain times. For |
| 283 | each condition, there's a bitmap of dis-allowed times. For some, it is easier |
| 284 | to specify the negation of a small number of allowed times. */ |
| 285 | |
| 286 | static unsigned int cond_forbids[] = { |
| 287 | 0, /* acl */ |
| 288 | |
| 289 | (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* authenticated */ |
| 290 | (1<<ACL_WHERE_HELO), |
| 291 | |
| 292 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 293 | (1<<ACL_WHERE_AUTH)| /* bmi_optin */ |
| 294 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 295 | (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_MIME)| |
| 296 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 297 | (1<<ACL_WHERE_MAILAUTH)| |
| 298 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 299 | (1<<ACL_WHERE_VRFY)|(1<<ACL_WHERE_PREDATA), |
| 300 | #endif |
| 301 | |
| 302 | 0, /* condition */ |
| 303 | |
| 304 | /* Certain types of control are always allowed, so we let it through |
| 305 | always and check in the control processing itself. */ |
| 306 | |
| 307 | 0, /* control */ |
| 308 | |
| 309 | #ifdef WITH_CONTENT_SCAN |
| 310 | (unsigned int) |
| 311 | ~(1<<ACL_WHERE_MIME), /* decode */ |
| 312 | #endif |
| 313 | |
| 314 | 0, /* delay */ |
| 315 | |
| 316 | #ifdef WITH_OLD_DEMIME |
| 317 | (unsigned int) |
| 318 | ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* demime */ |
| 319 | #endif |
| 320 | |
| 321 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 322 | (1<<ACL_WHERE_AUTH)| /* dk_domain_source */ |
| 323 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 324 | (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)| |
| 325 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 326 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 327 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 328 | (1<<ACL_WHERE_VRFY), |
| 329 | |
| 330 | (1<<ACL_WHERE_AUTH)| /* dk_policy */ |
| 331 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 332 | (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)| |
| 333 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 334 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 335 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 336 | (1<<ACL_WHERE_VRFY), |
| 337 | |
| 338 | (1<<ACL_WHERE_AUTH)| /* dk_sender_domains */ |
| 339 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 340 | (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)| |
| 341 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 342 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 343 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 344 | (1<<ACL_WHERE_VRFY), |
| 345 | |
| 346 | (1<<ACL_WHERE_AUTH)| /* dk_sender_local_parts */ |
| 347 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 348 | (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)| |
| 349 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 350 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 351 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 352 | (1<<ACL_WHERE_VRFY), |
| 353 | |
| 354 | (1<<ACL_WHERE_AUTH)| /* dk_senders */ |
| 355 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 356 | (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)| |
| 357 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 358 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 359 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 360 | (1<<ACL_WHERE_VRFY), |
| 361 | |
| 362 | (1<<ACL_WHERE_AUTH)| /* dk_status */ |
| 363 | (1<<ACL_WHERE_CONNECT)|(1<<ACL_WHERE_HELO)| |
| 364 | (1<<ACL_WHERE_RCPT)|(1<<ACL_WHERE_PREDATA)| |
| 365 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 366 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 367 | (1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_STARTTLS)| |
| 368 | (1<<ACL_WHERE_VRFY), |
| 369 | #endif |
| 370 | |
| 371 | (1<<ACL_WHERE_NOTSMTP), /* dnslists */ |
| 372 | |
| 373 | (unsigned int) |
| 374 | ~(1<<ACL_WHERE_RCPT), /* domains */ |
| 375 | |
| 376 | (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_CONNECT)| /* encrypted */ |
| 377 | (1<<ACL_WHERE_HELO), |
| 378 | |
| 379 | 0, /* endpass */ |
| 380 | |
| 381 | (1<<ACL_WHERE_NOTSMTP), /* hosts */ |
| 382 | |
| 383 | (unsigned int) |
| 384 | ~(1<<ACL_WHERE_RCPT), /* local_parts */ |
| 385 | |
| 386 | 0, /* log_message */ |
| 387 | |
| 388 | 0, /* logwrite */ |
| 389 | |
| 390 | #ifdef WITH_CONTENT_SCAN |
| 391 | (unsigned int) |
| 392 | ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* malware */ |
| 393 | #endif |
| 394 | |
| 395 | 0, /* message */ |
| 396 | |
| 397 | #ifdef WITH_CONTENT_SCAN |
| 398 | (unsigned int) |
| 399 | ~(1<<ACL_WHERE_MIME), /* mime_regex */ |
| 400 | #endif |
| 401 | |
| 402 | 0, /* ratelimit */ |
| 403 | |
| 404 | (unsigned int) |
| 405 | ~(1<<ACL_WHERE_RCPT), /* recipients */ |
| 406 | |
| 407 | #ifdef WITH_CONTENT_SCAN |
| 408 | (unsigned int) |
| 409 | ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)| /* regex */ |
| 410 | (1<<ACL_WHERE_MIME)), |
| 411 | #endif |
| 412 | |
| 413 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* sender_domains */ |
| 414 | (1<<ACL_WHERE_HELO)| |
| 415 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 416 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 417 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY), |
| 418 | |
| 419 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* senders */ |
| 420 | (1<<ACL_WHERE_HELO)| |
| 421 | (1<<ACL_WHERE_MAILAUTH)|(1<<ACL_WHERE_QUIT)| |
| 422 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 423 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY), |
| 424 | |
| 425 | 0, /* set */ |
| 426 | |
| 427 | #ifdef WITH_CONTENT_SCAN |
| 428 | (unsigned int) |
| 429 | ~((1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP)), /* spam */ |
| 430 | #endif |
| 431 | |
| 432 | #ifdef EXPERIMENTAL_SPF |
| 433 | (1<<ACL_WHERE_AUTH)|(1<<ACL_WHERE_CONNECT)| /* spf */ |
| 434 | (1<<ACL_WHERE_HELO)| |
| 435 | (1<<ACL_WHERE_MAILAUTH)| |
| 436 | (1<<ACL_WHERE_ETRN)|(1<<ACL_WHERE_EXPN)| |
| 437 | (1<<ACL_WHERE_STARTTLS)|(1<<ACL_WHERE_VRFY), |
| 438 | #endif |
| 439 | |
| 440 | /* Certain types of verify are always allowed, so we let it through |
| 441 | always and check in the verify function itself */ |
| 442 | |
| 443 | 0 /* verify */ |
| 444 | }; |
| 445 | |
| 446 | |
| 447 | /* Bit map vector of which controls are not allowed at certain times. For |
| 448 | each control, there's a bitmap of dis-allowed times. For some, it is easier to |
| 449 | specify the negation of a small number of allowed times. */ |
| 450 | |
| 451 | static unsigned int control_forbids[] = { |
| 452 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 453 | 0, /* bmi_run */ |
| 454 | #endif |
| 455 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 456 | (1<<ACL_WHERE_DATA)|(1<<ACL_WHERE_NOTSMTP), /* dk_verify */ |
| 457 | #endif |
| 458 | |
| 459 | 0, /* error */ |
| 460 | |
| 461 | (unsigned int) |
| 462 | ~(1<<ACL_WHERE_RCPT), /* caseful_local_part */ |
| 463 | |
| 464 | (unsigned int) |
| 465 | ~(1<<ACL_WHERE_RCPT), /* caselower_local_part */ |
| 466 | |
| 467 | (1<<ACL_WHERE_NOTSMTP), /* enforce_sync */ |
| 468 | |
| 469 | (1<<ACL_WHERE_NOTSMTP), /* no_enforce_sync */ |
| 470 | |
| 471 | (unsigned int) |
| 472 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* freeze */ |
| 473 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| |
| 474 | (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)), |
| 475 | |
| 476 | (unsigned int) |
| 477 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* queue_only */ |
| 478 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| |
| 479 | (1<<ACL_WHERE_NOTSMTP)|(1<<ACL_WHERE_MIME)), |
| 480 | |
| 481 | (unsigned int) |
| 482 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* submission */ |
| 483 | (1<<ACL_WHERE_PREDATA)), |
| 484 | |
| 485 | #ifdef WITH_CONTENT_SCAN |
| 486 | (unsigned int) |
| 487 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* no_mbox_unspool */ |
| 488 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| |
| 489 | (1<<ACL_WHERE_MIME)), |
| 490 | #endif |
| 491 | |
| 492 | (unsigned int) |
| 493 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakedefer */ |
| 494 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| |
| 495 | (1<<ACL_WHERE_MIME)), |
| 496 | |
| 497 | (unsigned int) |
| 498 | ~((1<<ACL_WHERE_MAIL)|(1<<ACL_WHERE_RCPT)| /* fakereject */ |
| 499 | (1<<ACL_WHERE_PREDATA)|(1<<ACL_WHERE_DATA)| |
| 500 | (1<<ACL_WHERE_MIME)), |
| 501 | |
| 502 | (1<<ACL_WHERE_NOTSMTP) /* no_multiline */ |
| 503 | }; |
| 504 | |
| 505 | /* Structure listing various control arguments, with their characteristics. */ |
| 506 | |
| 507 | typedef struct control_def { |
| 508 | uschar *name; |
| 509 | int value; /* CONTROL_xxx value */ |
| 510 | BOOL has_option; /* Has /option(s) following */ |
| 511 | } control_def; |
| 512 | |
| 513 | static control_def controls_list[] = { |
| 514 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 515 | { US"bmi_run", CONTROL_BMI_RUN, FALSE}, |
| 516 | #endif |
| 517 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 518 | { US"dk_verify", CONTROL_DK_VERIFY, FALSE}, |
| 519 | #endif |
| 520 | { US"caseful_local_part", CONTROL_CASEFUL_LOCAL_PART, FALSE}, |
| 521 | { US"caselower_local_part", CONTROL_CASELOWER_LOCAL_PART, FALSE}, |
| 522 | { US"enforce_sync", CONTROL_ENFORCE_SYNC, FALSE}, |
| 523 | { US"freeze", CONTROL_FREEZE, FALSE}, |
| 524 | { US"no_enforce_sync", CONTROL_NO_ENFORCE_SYNC, FALSE}, |
| 525 | { US"no_multiline_responses", CONTROL_NO_MULTILINE, FALSE}, |
| 526 | { US"queue_only", CONTROL_QUEUE_ONLY, FALSE}, |
| 527 | #ifdef WITH_CONTENT_SCAN |
| 528 | { US"no_mbox_unspool", CONTROL_NO_MBOX_UNSPOOL, FALSE}, |
| 529 | #endif |
| 530 | { US"fakedefer", CONTROL_FAKEDEFER, TRUE}, |
| 531 | { US"fakereject", CONTROL_FAKEREJECT, TRUE}, |
| 532 | { US"submission", CONTROL_SUBMISSION, TRUE} |
| 533 | }; |
| 534 | |
| 535 | /* Support data structures for Client SMTP Authorization. acl_verify_csa() |
| 536 | caches its result in a tree to avoid repeated DNS queries. The result is an |
| 537 | integer code which is used as an index into the following tables of |
| 538 | explanatory strings and verification return codes. */ |
| 539 | |
| 540 | static tree_node *csa_cache = NULL; |
| 541 | |
| 542 | enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR, |
| 543 | CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH }; |
| 544 | |
| 545 | /* The acl_verify_csa() return code is translated into an acl_verify() return |
| 546 | code using the following table. It is OK unless the client is definitely not |
| 547 | authorized. This is because CSA is supposed to be optional for sending sites, |
| 548 | so recipients should not be too strict about checking it - especially because |
| 549 | DNS problems are quite likely to occur. It's possible to use $csa_status in |
| 550 | further ACL conditions to distinguish ok, unknown, and defer if required, but |
| 551 | the aim is to make the usual configuration simple. */ |
| 552 | |
| 553 | static int csa_return_code[] = { |
| 554 | OK, OK, OK, OK, |
| 555 | FAIL, FAIL, FAIL, FAIL |
| 556 | }; |
| 557 | |
| 558 | static uschar *csa_status_string[] = { |
| 559 | US"unknown", US"ok", US"defer", US"defer", |
| 560 | US"fail", US"fail", US"fail", US"fail" |
| 561 | }; |
| 562 | |
| 563 | static uschar *csa_reason_string[] = { |
| 564 | US"unknown", |
| 565 | US"ok", |
| 566 | US"deferred (SRV lookup failed)", |
| 567 | US"deferred (target address lookup failed)", |
| 568 | US"failed (explicit authorization required)", |
| 569 | US"failed (host name not authorized)", |
| 570 | US"failed (no authorized addresses)", |
| 571 | US"failed (client address mismatch)" |
| 572 | }; |
| 573 | |
| 574 | /* Enable recursion between acl_check_internal() and acl_check_condition() */ |
| 575 | |
| 576 | static int acl_check_internal(int, address_item *, uschar *, int, uschar **, |
| 577 | uschar **); |
| 578 | |
| 579 | |
| 580 | /************************************************* |
| 581 | * Pick out name from list * |
| 582 | *************************************************/ |
| 583 | |
| 584 | /* Use a binary chop method |
| 585 | |
| 586 | Arguments: |
| 587 | name name to find |
| 588 | list list of names |
| 589 | end size of list |
| 590 | |
| 591 | Returns: offset in list, or -1 if not found |
| 592 | */ |
| 593 | |
| 594 | static int |
| 595 | acl_checkname(uschar *name, uschar **list, int end) |
| 596 | { |
| 597 | int start = 0; |
| 598 | |
| 599 | while (start < end) |
| 600 | { |
| 601 | int mid = (start + end)/2; |
| 602 | int c = Ustrcmp(name, list[mid]); |
| 603 | if (c == 0) return mid; |
| 604 | if (c < 0) end = mid; else start = mid + 1; |
| 605 | } |
| 606 | |
| 607 | return -1; |
| 608 | } |
| 609 | |
| 610 | |
| 611 | /************************************************* |
| 612 | * Read and parse one ACL * |
| 613 | *************************************************/ |
| 614 | |
| 615 | /* This function is called both from readconf in order to parse the ACLs in the |
| 616 | configuration file, and also when an ACL is encountered dynamically (e.g. as |
| 617 | the result of an expansion). It is given a function to call in order to |
| 618 | retrieve the lines of the ACL. This function handles skipping comments and |
| 619 | blank lines (where relevant). |
| 620 | |
| 621 | Arguments: |
| 622 | func function to get next line of ACL |
| 623 | error where to put an error message |
| 624 | |
| 625 | Returns: pointer to ACL, or NULL |
| 626 | NULL can be legal (empty ACL); in this case error will be NULL |
| 627 | */ |
| 628 | |
| 629 | acl_block * |
| 630 | acl_read(uschar *(*func)(void), uschar **error) |
| 631 | { |
| 632 | acl_block *yield = NULL; |
| 633 | acl_block **lastp = &yield; |
| 634 | acl_block *this = NULL; |
| 635 | acl_condition_block *cond; |
| 636 | acl_condition_block **condp = NULL; |
| 637 | uschar *s; |
| 638 | |
| 639 | *error = NULL; |
| 640 | |
| 641 | while ((s = (*func)()) != NULL) |
| 642 | { |
| 643 | int v, c; |
| 644 | BOOL negated = FALSE; |
| 645 | uschar *saveline = s; |
| 646 | uschar name[64]; |
| 647 | |
| 648 | /* Conditions (but not verbs) are allowed to be negated by an initial |
| 649 | exclamation mark. */ |
| 650 | |
| 651 | while (isspace(*s)) s++; |
| 652 | if (*s == '!') |
| 653 | { |
| 654 | negated = TRUE; |
| 655 | s++; |
| 656 | } |
| 657 | |
| 658 | /* Read the name of a verb or a condition, or the start of a new ACL, which |
| 659 | can be started by a name, or by a macro definition. */ |
| 660 | |
| 661 | s = readconf_readname(name, sizeof(name), s); |
| 662 | if (*s == ':' || isupper(name[0] && *s == '=')) return yield; |
| 663 | |
| 664 | /* If a verb is unrecognized, it may be another condition or modifier that |
| 665 | continues the previous verb. */ |
| 666 | |
| 667 | v = acl_checkname(name, verbs, sizeof(verbs)/sizeof(char *)); |
| 668 | if (v < 0) |
| 669 | { |
| 670 | if (this == NULL) |
| 671 | { |
| 672 | *error = string_sprintf("unknown ACL verb in \"%s\"", saveline); |
| 673 | return NULL; |
| 674 | } |
| 675 | } |
| 676 | |
| 677 | /* New verb */ |
| 678 | |
| 679 | else |
| 680 | { |
| 681 | if (negated) |
| 682 | { |
| 683 | *error = string_sprintf("malformed ACL line \"%s\"", saveline); |
| 684 | return NULL; |
| 685 | } |
| 686 | this = store_get(sizeof(acl_block)); |
| 687 | *lastp = this; |
| 688 | lastp = &(this->next); |
| 689 | this->next = NULL; |
| 690 | this->verb = v; |
| 691 | this->condition = NULL; |
| 692 | condp = &(this->condition); |
| 693 | if (*s == 0) continue; /* No condition on this line */ |
| 694 | if (*s == '!') |
| 695 | { |
| 696 | negated = TRUE; |
| 697 | s++; |
| 698 | } |
| 699 | s = readconf_readname(name, sizeof(name), s); /* Condition name */ |
| 700 | } |
| 701 | |
| 702 | /* Handle a condition or modifier. */ |
| 703 | |
| 704 | c = acl_checkname(name, conditions, sizeof(conditions)/sizeof(char *)); |
| 705 | if (c < 0) |
| 706 | { |
| 707 | *error = string_sprintf("unknown ACL condition/modifier in \"%s\"", |
| 708 | saveline); |
| 709 | return NULL; |
| 710 | } |
| 711 | |
| 712 | /* The modifiers may not be negated */ |
| 713 | |
| 714 | if (negated && cond_modifiers[c]) |
| 715 | { |
| 716 | *error = string_sprintf("ACL error: negation is not allowed with " |
| 717 | "\"%s\"", conditions[c]); |
| 718 | return NULL; |
| 719 | } |
| 720 | |
| 721 | /* ENDPASS may occur only with ACCEPT or DISCARD. */ |
| 722 | |
| 723 | if (c == ACLC_ENDPASS && |
| 724 | this->verb != ACL_ACCEPT && |
| 725 | this->verb != ACL_DISCARD) |
| 726 | { |
| 727 | *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"", |
| 728 | conditions[c], verbs[this->verb]); |
| 729 | return NULL; |
| 730 | } |
| 731 | |
| 732 | cond = store_get(sizeof(acl_condition_block)); |
| 733 | cond->next = NULL; |
| 734 | cond->type = c; |
| 735 | cond->u.negated = negated; |
| 736 | |
| 737 | *condp = cond; |
| 738 | condp = &(cond->next); |
| 739 | |
| 740 | /* The "set" modifier is different in that its argument is "name=value" |
| 741 | rather than just a value, and we can check the validity of the name, which |
| 742 | gives us a variable number to insert into the data block. */ |
| 743 | |
| 744 | if (c == ACLC_SET) |
| 745 | { |
| 746 | if (Ustrncmp(s, "acl_", 4) != 0 || (s[4] != 'c' && s[4] != 'm') || |
| 747 | !isdigit(s[5]) || (!isspace(s[6]) && s[6] != '=')) |
| 748 | { |
| 749 | *error = string_sprintf("unrecognized name after \"set\" in ACL " |
| 750 | "modifier \"set %s\"", s); |
| 751 | return NULL; |
| 752 | } |
| 753 | |
| 754 | cond->u.varnumber = s[5] - '0'; |
| 755 | if (s[4] == 'm') cond->u.varnumber += ACL_C_MAX; |
| 756 | s += 6; |
| 757 | while (isspace(*s)) s++; |
| 758 | } |
| 759 | |
| 760 | /* For "set", we are now positioned for the data. For the others, only |
| 761 | "endpass" has no data */ |
| 762 | |
| 763 | if (c != ACLC_ENDPASS) |
| 764 | { |
| 765 | if (*s++ != '=') |
| 766 | { |
| 767 | *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name, |
| 768 | cond_modifiers[c]? US"modifier" : US"condition"); |
| 769 | return NULL; |
| 770 | } |
| 771 | while (isspace(*s)) s++; |
| 772 | cond->arg = string_copy(s); |
| 773 | } |
| 774 | } |
| 775 | |
| 776 | return yield; |
| 777 | } |
| 778 | |
| 779 | |
| 780 | |
| 781 | /************************************************* |
| 782 | * Handle warnings * |
| 783 | *************************************************/ |
| 784 | |
| 785 | /* This function is called when a WARN verb's conditions are true. It adds to |
| 786 | the message's headers, and/or writes information to the log. In each case, this |
| 787 | only happens once (per message for headers, per connection for log). |
| 788 | |
| 789 | Arguments: |
| 790 | where ACL_WHERE_xxxx indicating which ACL this is |
| 791 | user_message message for adding to headers |
| 792 | log_message message for logging, if different |
| 793 | |
| 794 | Returns: nothing |
| 795 | */ |
| 796 | |
| 797 | static void |
| 798 | acl_warn(int where, uschar *user_message, uschar *log_message) |
| 799 | { |
| 800 | int hlen; |
| 801 | |
| 802 | if (log_message != NULL && log_message != user_message) |
| 803 | { |
| 804 | uschar *text; |
| 805 | string_item *logged; |
| 806 | |
| 807 | text = string_sprintf("%s Warning: %s", host_and_ident(TRUE), |
| 808 | string_printing(log_message)); |
| 809 | |
| 810 | /* If a sender verification has failed, and the log message is "sender verify |
| 811 | failed", add the failure message. */ |
| 812 | |
| 813 | if (sender_verified_failed != NULL && |
| 814 | sender_verified_failed->message != NULL && |
| 815 | strcmpic(log_message, US"sender verify failed") == 0) |
| 816 | text = string_sprintf("%s: %s", text, sender_verified_failed->message); |
| 817 | |
| 818 | /* Search previously logged warnings. They are kept in malloc |
| 819 | store so they can be freed at the start of a new message. */ |
| 820 | |
| 821 | for (logged = acl_warn_logged; logged != NULL; logged = logged->next) |
| 822 | if (Ustrcmp(logged->text, text) == 0) break; |
| 823 | |
| 824 | if (logged == NULL) |
| 825 | { |
| 826 | int length = Ustrlen(text) + 1; |
| 827 | log_write(0, LOG_MAIN, "%s", text); |
| 828 | logged = store_malloc(sizeof(string_item) + length); |
| 829 | logged->text = (uschar *)logged + sizeof(string_item); |
| 830 | memcpy(logged->text, text, length); |
| 831 | logged->next = acl_warn_logged; |
| 832 | acl_warn_logged = logged; |
| 833 | } |
| 834 | } |
| 835 | |
| 836 | /* If there's no user message, we are done. */ |
| 837 | |
| 838 | if (user_message == NULL) return; |
| 839 | |
| 840 | /* If this isn't a message ACL, we can't do anything with a user message. |
| 841 | Log an error. */ |
| 842 | |
| 843 | if (where > ACL_WHERE_NOTSMTP) |
| 844 | { |
| 845 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting " |
| 846 | "found in a non-message (%s) ACL: cannot specify header lines here: " |
| 847 | "message ignored", acl_wherenames[where]); |
| 848 | return; |
| 849 | } |
| 850 | |
| 851 | /* Treat the user message as a sequence of one or more header lines. */ |
| 852 | |
| 853 | hlen = Ustrlen(user_message); |
| 854 | if (hlen > 0) |
| 855 | { |
| 856 | uschar *text, *p, *q; |
| 857 | |
| 858 | /* Add a final newline if not present */ |
| 859 | |
| 860 | text = ((user_message)[hlen-1] == '\n')? user_message : |
| 861 | string_sprintf("%s\n", user_message); |
| 862 | |
| 863 | /* Loop for multiple header lines, taking care about continuations */ |
| 864 | |
| 865 | for (p = q = text; *p != 0; ) |
| 866 | { |
| 867 | uschar *s; |
| 868 | int newtype = htype_add_bot; |
| 869 | header_line **hptr = &acl_warn_headers; |
| 870 | |
| 871 | /* Find next header line within the string */ |
| 872 | |
| 873 | for (;;) |
| 874 | { |
| 875 | q = Ustrchr(q, '\n'); |
| 876 | if (*(++q) != ' ' && *q != '\t') break; |
| 877 | } |
| 878 | |
| 879 | /* If the line starts with a colon, interpret the instruction for where to |
| 880 | add it. This temporarily sets up a new type. */ |
| 881 | |
| 882 | if (*p == ':') |
| 883 | { |
| 884 | if (strncmpic(p, US":after_received:", 16) == 0) |
| 885 | { |
| 886 | newtype = htype_add_rec; |
| 887 | p += 16; |
| 888 | } |
| 889 | else if (strncmpic(p, US":at_start_rfc:", 14) == 0) |
| 890 | { |
| 891 | newtype = htype_add_rfc; |
| 892 | p += 14; |
| 893 | } |
| 894 | else if (strncmpic(p, US":at_start:", 10) == 0) |
| 895 | { |
| 896 | newtype = htype_add_top; |
| 897 | p += 10; |
| 898 | } |
| 899 | else if (strncmpic(p, US":at_end:", 8) == 0) |
| 900 | { |
| 901 | newtype = htype_add_bot; |
| 902 | p += 8; |
| 903 | } |
| 904 | while (*p == ' ' || *p == '\t') p++; |
| 905 | } |
| 906 | |
| 907 | /* See if this line starts with a header name, and if not, add X-ACL-Warn: |
| 908 | to the front of it. */ |
| 909 | |
| 910 | for (s = p; s < q - 1; s++) |
| 911 | { |
| 912 | if (*s == ':' || !isgraph(*s)) break; |
| 913 | } |
| 914 | |
| 915 | s = string_sprintf("%s%.*s", (*s == ':')? "" : "X-ACL-Warn: ", q - p, p); |
| 916 | hlen = Ustrlen(s); |
| 917 | |
| 918 | /* See if this line has already been added */ |
| 919 | |
| 920 | while (*hptr != NULL) |
| 921 | { |
| 922 | if (Ustrncmp((*hptr)->text, s, hlen) == 0) break; |
| 923 | hptr = &((*hptr)->next); |
| 924 | } |
| 925 | |
| 926 | /* Add if not previously present */ |
| 927 | |
| 928 | if (*hptr == NULL) |
| 929 | { |
| 930 | header_line *h = store_get(sizeof(header_line)); |
| 931 | h->text = s; |
| 932 | h->next = NULL; |
| 933 | h->type = newtype; |
| 934 | h->slen = hlen; |
| 935 | *hptr = h; |
| 936 | hptr = &(h->next); |
| 937 | } |
| 938 | |
| 939 | /* Advance for next header line within the string */ |
| 940 | |
| 941 | p = q; |
| 942 | } |
| 943 | } |
| 944 | } |
| 945 | |
| 946 | |
| 947 | |
| 948 | /************************************************* |
| 949 | * Verify and check reverse DNS * |
| 950 | *************************************************/ |
| 951 | |
| 952 | /* Called from acl_verify() below. We look up the host name(s) of the client IP |
| 953 | address if this has not yet been done. The host_name_lookup() function checks |
| 954 | that one of these names resolves to an address list that contains the client IP |
| 955 | address, so we don't actually have to do the check here. |
| 956 | |
| 957 | Arguments: |
| 958 | user_msgptr pointer for user message |
| 959 | log_msgptr pointer for log message |
| 960 | |
| 961 | Returns: OK verification condition succeeded |
| 962 | FAIL verification failed |
| 963 | DEFER there was a problem verifying |
| 964 | */ |
| 965 | |
| 966 | static int |
| 967 | acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr) |
| 968 | { |
| 969 | int rc; |
| 970 | |
| 971 | user_msgptr = user_msgptr; /* stop compiler warning */ |
| 972 | |
| 973 | /* Previous success */ |
| 974 | |
| 975 | if (sender_host_name != NULL) return OK; |
| 976 | |
| 977 | /* Previous failure */ |
| 978 | |
| 979 | if (host_lookup_failed) |
| 980 | { |
| 981 | *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg); |
| 982 | return FAIL; |
| 983 | } |
| 984 | |
| 985 | /* Need to do a lookup */ |
| 986 | |
| 987 | HDEBUG(D_acl) |
| 988 | debug_printf("looking up host name to force name/address consistency check\n"); |
| 989 | |
| 990 | if ((rc = host_name_lookup()) != OK) |
| 991 | { |
| 992 | *log_msgptr = (rc == DEFER)? |
| 993 | US"host lookup deferred for reverse lookup check" |
| 994 | : |
| 995 | string_sprintf("host lookup failed for reverse lookup check%s", |
| 996 | host_lookup_msg); |
| 997 | return rc; /* DEFER or FAIL */ |
| 998 | } |
| 999 | |
| 1000 | host_build_sender_fullhost(); |
| 1001 | return OK; |
| 1002 | } |
| 1003 | |
| 1004 | |
| 1005 | |
| 1006 | /************************************************* |
| 1007 | * Check client IP address matches CSA target * |
| 1008 | *************************************************/ |
| 1009 | |
| 1010 | /* Called from acl_verify_csa() below. This routine scans a section of a DNS |
| 1011 | response for address records belonging to the CSA target hostname. The section |
| 1012 | is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS. |
| 1013 | If one of the addresses matches the client's IP address, then the client is |
| 1014 | authorized by CSA. If there are target IP addresses but none of them match |
| 1015 | then the client is using an unauthorized IP address. If there are no target IP |
| 1016 | addresses then the client cannot be using an authorized IP address. (This is |
| 1017 | an odd configuration - why didn't the SRV record have a weight of 1 instead?) |
| 1018 | |
| 1019 | Arguments: |
| 1020 | dnsa the DNS answer block |
| 1021 | dnss a DNS scan block for us to use |
| 1022 | reset option specifing what portion to scan, as described above |
| 1023 | target the target hostname to use for matching RR names |
| 1024 | |
| 1025 | Returns: CSA_OK successfully authorized |
| 1026 | CSA_FAIL_MISMATCH addresses found but none matched |
| 1027 | CSA_FAIL_NOADDR no target addresses found |
| 1028 | */ |
| 1029 | |
| 1030 | static int |
| 1031 | acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset, |
| 1032 | uschar *target) |
| 1033 | { |
| 1034 | dns_record *rr; |
| 1035 | dns_address *da; |
| 1036 | |
| 1037 | BOOL target_found = FALSE; |
| 1038 | |
| 1039 | for (rr = dns_next_rr(dnsa, dnss, reset); |
| 1040 | rr != NULL; |
| 1041 | rr = dns_next_rr(dnsa, dnss, RESET_NEXT)) |
| 1042 | { |
| 1043 | /* Check this is an address RR for the target hostname. */ |
| 1044 | |
| 1045 | if (rr->type != T_A |
| 1046 | #if HAVE_IPV6 |
| 1047 | && rr->type != T_AAAA |
| 1048 | #ifdef SUPPORT_A6 |
| 1049 | && rr->type != T_A6 |
| 1050 | #endif |
| 1051 | #endif |
| 1052 | ) continue; |
| 1053 | |
| 1054 | if (strcmpic(target, rr->name) != 0) continue; |
| 1055 | |
| 1056 | target_found = TRUE; |
| 1057 | |
| 1058 | /* Turn the target address RR into a list of textual IP addresses and scan |
| 1059 | the list. There may be more than one if it is an A6 RR. */ |
| 1060 | |
| 1061 | for (da = dns_address_from_rr(dnsa, rr); da != NULL; da = da->next) |
| 1062 | { |
| 1063 | /* If the client IP address matches the target IP address, it's good! */ |
| 1064 | |
| 1065 | DEBUG(D_acl) debug_printf("CSA target address is %s\n", da->address); |
| 1066 | |
| 1067 | if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK; |
| 1068 | } |
| 1069 | } |
| 1070 | |
| 1071 | /* If we found some target addresses but none of them matched, the client is |
| 1072 | using an unauthorized IP address, otherwise the target has no authorized IP |
| 1073 | addresses. */ |
| 1074 | |
| 1075 | if (target_found) return CSA_FAIL_MISMATCH; |
| 1076 | else return CSA_FAIL_NOADDR; |
| 1077 | } |
| 1078 | |
| 1079 | |
| 1080 | |
| 1081 | /************************************************* |
| 1082 | * Verify Client SMTP Authorization * |
| 1083 | *************************************************/ |
| 1084 | |
| 1085 | /* Called from acl_verify() below. This routine calls dns_lookup_special() |
| 1086 | to find the CSA SRV record corresponding to the domain argument, or |
| 1087 | $sender_helo_name if no argument is provided. It then checks that the |
| 1088 | client is authorized, and that its IP address corresponds to the SRV |
| 1089 | target's address by calling acl_verify_csa_address() above. The address |
| 1090 | should have been returned in the DNS response's ADDITIONAL section, but if |
| 1091 | not we perform another DNS lookup to get it. |
| 1092 | |
| 1093 | Arguments: |
| 1094 | domain pointer to optional parameter following verify = csa |
| 1095 | |
| 1096 | Returns: CSA_UNKNOWN no valid CSA record found |
| 1097 | CSA_OK successfully authorized |
| 1098 | CSA_FAIL_* client is definitely not authorized |
| 1099 | CSA_DEFER_* there was a DNS problem |
| 1100 | */ |
| 1101 | |
| 1102 | static int |
| 1103 | acl_verify_csa(uschar *domain) |
| 1104 | { |
| 1105 | tree_node *t; |
| 1106 | uschar *found, *p; |
| 1107 | int priority, weight, port; |
| 1108 | dns_answer dnsa; |
| 1109 | dns_scan dnss; |
| 1110 | dns_record *rr; |
| 1111 | int rc, type; |
| 1112 | uschar target[256]; |
| 1113 | |
| 1114 | /* Work out the domain we are using for the CSA lookup. The default is the |
| 1115 | client's HELO domain. If the client has not said HELO, use its IP address |
| 1116 | instead. If it's a local client (exim -bs), CSA isn't applicable. */ |
| 1117 | |
| 1118 | while (isspace(*domain) && *domain != '\0') ++domain; |
| 1119 | if (*domain == '\0') domain = sender_helo_name; |
| 1120 | if (domain == NULL) domain = sender_host_address; |
| 1121 | if (sender_host_address == NULL) return CSA_UNKNOWN; |
| 1122 | |
| 1123 | /* If we have an address literal, strip off the framing ready for turning it |
| 1124 | into a domain. The framing consists of matched square brackets possibly |
| 1125 | containing a keyword and a colon before the actual IP address. */ |
| 1126 | |
| 1127 | if (domain[0] == '[') |
| 1128 | { |
| 1129 | uschar *start = Ustrchr(domain, ':'); |
| 1130 | if (start == NULL) start = domain; |
| 1131 | domain = string_copyn(start + 1, Ustrlen(start) - 2); |
| 1132 | } |
| 1133 | |
| 1134 | /* Turn domains that look like bare IP addresses into domains in the reverse |
| 1135 | DNS. This code also deals with address literals and $sender_host_address. It's |
| 1136 | not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as |
| 1137 | address literals, but it's probably the most friendly thing to do. This is an |
| 1138 | extension to CSA, so we allow it to be turned off for proper conformance. */ |
| 1139 | |
| 1140 | if (string_is_ip_address(domain, NULL)) |
| 1141 | { |
| 1142 | if (!dns_csa_use_reverse) return CSA_UNKNOWN; |
| 1143 | dns_build_reverse(domain, target); |
| 1144 | domain = target; |
| 1145 | } |
| 1146 | |
| 1147 | /* Find out if we've already done the CSA check for this domain. If we have, |
| 1148 | return the same result again. Otherwise build a new cached result structure |
| 1149 | for this domain. The name is filled in now, and the value is filled in when |
| 1150 | we return from this function. */ |
| 1151 | |
| 1152 | t = tree_search(csa_cache, domain); |
| 1153 | if (t != NULL) return t->data.val; |
| 1154 | |
| 1155 | t = store_get_perm(sizeof(tree_node) + Ustrlen(domain)); |
| 1156 | Ustrcpy(t->name, domain); |
| 1157 | (void)tree_insertnode(&csa_cache, t); |
| 1158 | |
| 1159 | /* Now we are ready to do the actual DNS lookup(s). */ |
| 1160 | |
| 1161 | found = domain; |
| 1162 | switch (dns_special_lookup(&dnsa, domain, T_CSA, &found)) |
| 1163 | { |
| 1164 | /* If something bad happened (most commonly DNS_AGAIN), defer. */ |
| 1165 | |
| 1166 | default: |
| 1167 | return t->data.val = CSA_DEFER_SRV; |
| 1168 | |
| 1169 | /* If we found nothing, the client's authorization is unknown. */ |
| 1170 | |
| 1171 | case DNS_NOMATCH: |
| 1172 | case DNS_NODATA: |
| 1173 | return t->data.val = CSA_UNKNOWN; |
| 1174 | |
| 1175 | /* We got something! Go on to look at the reply in more detail. */ |
| 1176 | |
| 1177 | case DNS_SUCCEED: |
| 1178 | break; |
| 1179 | } |
| 1180 | |
| 1181 | /* Scan the reply for well-formed CSA SRV records. */ |
| 1182 | |
| 1183 | for (rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); |
| 1184 | rr != NULL; |
| 1185 | rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT)) |
| 1186 | { |
| 1187 | if (rr->type != T_SRV) continue; |
| 1188 | |
| 1189 | /* Extract the numerical SRV fields (p is incremented) */ |
| 1190 | |
| 1191 | p = rr->data; |
| 1192 | GETSHORT(priority, p); |
| 1193 | GETSHORT(weight, p); |
| 1194 | GETSHORT(port, p); |
| 1195 | |
| 1196 | DEBUG(D_acl) |
| 1197 | debug_printf("CSA priority=%d weight=%d port=%d\n", priority, weight, port); |
| 1198 | |
| 1199 | /* Check the CSA version number */ |
| 1200 | |
| 1201 | if (priority != 1) continue; |
| 1202 | |
| 1203 | /* If the domain does not have a CSA SRV record of its own (i.e. the domain |
| 1204 | found by dns_special_lookup() is a parent of the one we asked for), we check |
| 1205 | the subdomain assertions in the port field. At the moment there's only one |
| 1206 | assertion: legitimate SMTP clients are all explicitly authorized with CSA |
| 1207 | SRV records of their own. */ |
| 1208 | |
| 1209 | if (found != domain) |
| 1210 | { |
| 1211 | if (port & 1) |
| 1212 | return t->data.val = CSA_FAIL_EXPLICIT; |
| 1213 | else |
| 1214 | return t->data.val = CSA_UNKNOWN; |
| 1215 | } |
| 1216 | |
| 1217 | /* This CSA SRV record refers directly to our domain, so we check the value |
| 1218 | in the weight field to work out the domain's authorization. 0 and 1 are |
| 1219 | unauthorized; 3 means the client is authorized but we can't check the IP |
| 1220 | address in order to authenticate it, so we treat it as unknown; values |
| 1221 | greater than 3 are undefined. */ |
| 1222 | |
| 1223 | if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN; |
| 1224 | |
| 1225 | if (weight > 2) continue; |
| 1226 | |
| 1227 | /* Weight == 2, which means the domain is authorized. We must check that the |
| 1228 | client's IP address is listed as one of the SRV target addresses. Save the |
| 1229 | target hostname then break to scan the additional data for its addresses. */ |
| 1230 | |
| 1231 | (void)dn_expand(dnsa.answer, dnsa.answer + dnsa.answerlen, p, |
| 1232 | (DN_EXPAND_ARG4_TYPE)target, sizeof(target)); |
| 1233 | |
| 1234 | DEBUG(D_acl) debug_printf("CSA target is %s\n", target); |
| 1235 | |
| 1236 | break; |
| 1237 | } |
| 1238 | |
| 1239 | /* If we didn't break the loop then no appropriate records were found. */ |
| 1240 | |
| 1241 | if (rr == NULL) return t->data.val = CSA_UNKNOWN; |
| 1242 | |
| 1243 | /* Do not check addresses if the target is ".", in accordance with RFC 2782. |
| 1244 | A target of "." indicates there are no valid addresses, so the client cannot |
| 1245 | be authorized. (This is an odd configuration because weight=2 target=. is |
| 1246 | equivalent to weight=1, but we check for it in order to keep load off the |
| 1247 | root name servers.) Note that dn_expand() turns "." into "". */ |
| 1248 | |
| 1249 | if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR; |
| 1250 | |
| 1251 | /* Scan the additional section of the CSA SRV reply for addresses belonging |
| 1252 | to the target. If the name server didn't return any additional data (e.g. |
| 1253 | because it does not fully support SRV records), we need to do another lookup |
| 1254 | to obtain the target addresses; otherwise we have a definitive result. */ |
| 1255 | |
| 1256 | rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ADDITIONAL, target); |
| 1257 | if (rc != CSA_FAIL_NOADDR) return t->data.val = rc; |
| 1258 | |
| 1259 | /* The DNS lookup type corresponds to the IP version used by the client. */ |
| 1260 | |
| 1261 | #if HAVE_IPV6 |
| 1262 | if (Ustrchr(sender_host_address, ':') != NULL) |
| 1263 | type = T_AAAA; |
| 1264 | else |
| 1265 | #endif /* HAVE_IPV6 */ |
| 1266 | type = T_A; |
| 1267 | |
| 1268 | |
| 1269 | #if HAVE_IPV6 && defined(SUPPORT_A6) |
| 1270 | DNS_LOOKUP_AGAIN: |
| 1271 | #endif |
| 1272 | |
| 1273 | switch (dns_lookup(&dnsa, target, type, NULL)) |
| 1274 | { |
| 1275 | /* If something bad happened (most commonly DNS_AGAIN), defer. */ |
| 1276 | |
| 1277 | default: |
| 1278 | return t->data.val = CSA_DEFER_ADDR; |
| 1279 | |
| 1280 | /* If the query succeeded, scan the addresses and return the result. */ |
| 1281 | |
| 1282 | case DNS_SUCCEED: |
| 1283 | rc = acl_verify_csa_address(&dnsa, &dnss, RESET_ANSWERS, target); |
| 1284 | if (rc != CSA_FAIL_NOADDR) return t->data.val = rc; |
| 1285 | /* else fall through */ |
| 1286 | |
| 1287 | /* If the target has no IP addresses, the client cannot have an authorized |
| 1288 | IP address. However, if the target site uses A6 records (not AAAA records) |
| 1289 | we have to do yet another lookup in order to check them. */ |
| 1290 | |
| 1291 | case DNS_NOMATCH: |
| 1292 | case DNS_NODATA: |
| 1293 | |
| 1294 | #if HAVE_IPV6 && defined(SUPPORT_A6) |
| 1295 | if (type == T_AAAA) { type = T_A6; goto DNS_LOOKUP_AGAIN; } |
| 1296 | #endif |
| 1297 | |
| 1298 | return t->data.val = CSA_FAIL_NOADDR; |
| 1299 | } |
| 1300 | } |
| 1301 | |
| 1302 | |
| 1303 | |
| 1304 | /************************************************* |
| 1305 | * Handle verification (address & other) * |
| 1306 | *************************************************/ |
| 1307 | |
| 1308 | /* This function implements the "verify" condition. It is called when |
| 1309 | encountered in any ACL, because some tests are almost always permitted. Some |
| 1310 | just don't make sense, and always fail (for example, an attempt to test a host |
| 1311 | lookup for a non-TCP/IP message). Others are restricted to certain ACLs. |
| 1312 | |
| 1313 | Arguments: |
| 1314 | where where called from |
| 1315 | addr the recipient address that the ACL is handling, or NULL |
| 1316 | arg the argument of "verify" |
| 1317 | user_msgptr pointer for user message |
| 1318 | log_msgptr pointer for log message |
| 1319 | basic_errno where to put verify errno |
| 1320 | |
| 1321 | Returns: OK verification condition succeeded |
| 1322 | FAIL verification failed |
| 1323 | DEFER there was a problem verifying |
| 1324 | ERROR syntax error |
| 1325 | */ |
| 1326 | |
| 1327 | static int |
| 1328 | acl_verify(int where, address_item *addr, uschar *arg, |
| 1329 | uschar **user_msgptr, uschar **log_msgptr, int *basic_errno) |
| 1330 | { |
| 1331 | int sep = '/'; |
| 1332 | int callout = -1; |
| 1333 | int callout_overall = -1; |
| 1334 | int callout_connect = -1; |
| 1335 | int verify_options = 0; |
| 1336 | int rc; |
| 1337 | BOOL verify_header_sender = FALSE; |
| 1338 | BOOL defer_ok = FALSE; |
| 1339 | BOOL callout_defer_ok = FALSE; |
| 1340 | BOOL no_details = FALSE; |
| 1341 | BOOL success_on_redirect = FALSE; |
| 1342 | address_item *sender_vaddr = NULL; |
| 1343 | uschar *verify_sender_address = NULL; |
| 1344 | uschar *pm_mailfrom = NULL; |
| 1345 | uschar *se_mailfrom = NULL; |
| 1346 | |
| 1347 | /* Some of the verify items have slash-separated options; some do not. Diagnose |
| 1348 | an error if options are given for items that don't expect them. This code has |
| 1349 | now got very message. Refactoring to use a table would be a good idea one day. |
| 1350 | */ |
| 1351 | |
| 1352 | uschar *slash = Ustrchr(arg, '/'); |
| 1353 | uschar *list = arg; |
| 1354 | uschar *ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size); |
| 1355 | |
| 1356 | if (ss == NULL) goto BAD_VERIFY; |
| 1357 | |
| 1358 | /* Handle name/address consistency verification in a separate function. */ |
| 1359 | |
| 1360 | if (strcmpic(ss, US"reverse_host_lookup") == 0) |
| 1361 | { |
| 1362 | if (slash != NULL) goto NO_OPTIONS; |
| 1363 | if (sender_host_address == NULL) return OK; |
| 1364 | return acl_verify_reverse(user_msgptr, log_msgptr); |
| 1365 | } |
| 1366 | |
| 1367 | /* TLS certificate verification is done at STARTTLS time; here we just |
| 1368 | test whether it was successful or not. (This is for optional verification; for |
| 1369 | mandatory verification, the connection doesn't last this long.) */ |
| 1370 | |
| 1371 | if (strcmpic(ss, US"certificate") == 0) |
| 1372 | { |
| 1373 | if (slash != NULL) goto NO_OPTIONS; |
| 1374 | if (tls_certificate_verified) return OK; |
| 1375 | *user_msgptr = US"no verified certificate"; |
| 1376 | return FAIL; |
| 1377 | } |
| 1378 | |
| 1379 | /* We can test the result of optional HELO verification */ |
| 1380 | |
| 1381 | if (strcmpic(ss, US"helo") == 0) |
| 1382 | { |
| 1383 | if (slash != NULL) goto NO_OPTIONS; |
| 1384 | return helo_verified? OK : FAIL; |
| 1385 | } |
| 1386 | |
| 1387 | /* Do Client SMTP Authorization checks in a separate function, and turn the |
| 1388 | result code into user-friendly strings. */ |
| 1389 | |
| 1390 | if (strcmpic(ss, US"csa") == 0) |
| 1391 | { |
| 1392 | rc = acl_verify_csa(list); |
| 1393 | *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s", |
| 1394 | csa_reason_string[rc]); |
| 1395 | csa_status = csa_status_string[rc]; |
| 1396 | DEBUG(D_acl) debug_printf("CSA result %s\n", csa_status); |
| 1397 | return csa_return_code[rc]; |
| 1398 | } |
| 1399 | |
| 1400 | /* Check that all relevant header lines have the correct syntax. If there is |
| 1401 | a syntax error, we return details of the error to the sender if configured to |
| 1402 | send out full details. (But a "message" setting on the ACL can override, as |
| 1403 | always). */ |
| 1404 | |
| 1405 | if (strcmpic(ss, US"header_syntax") == 0) |
| 1406 | { |
| 1407 | if (slash != NULL) goto NO_OPTIONS; |
| 1408 | if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) |
| 1409 | { |
| 1410 | *log_msgptr = string_sprintf("cannot check header contents in ACL for %s " |
| 1411 | "(only possible in ACL for DATA)", acl_wherenames[where]); |
| 1412 | return ERROR; |
| 1413 | } |
| 1414 | rc = verify_check_headers(log_msgptr); |
| 1415 | if (rc != OK && smtp_return_error_details && *log_msgptr != NULL) |
| 1416 | *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr); |
| 1417 | return rc; |
| 1418 | } |
| 1419 | |
| 1420 | |
| 1421 | /* The remaining verification tests check recipient and sender addresses, |
| 1422 | either from the envelope or from the header. There are a number of |
| 1423 | slash-separated options that are common to all of them. */ |
| 1424 | |
| 1425 | |
| 1426 | /* Check that there is at least one verifiable sender address in the relevant |
| 1427 | header lines. This can be followed by callout and defer options, just like |
| 1428 | sender and recipient. */ |
| 1429 | |
| 1430 | if (strcmpic(ss, US"header_sender") == 0) |
| 1431 | { |
| 1432 | if (where != ACL_WHERE_DATA && where != ACL_WHERE_NOTSMTP) |
| 1433 | { |
| 1434 | *log_msgptr = string_sprintf("cannot check header contents in ACL for %s " |
| 1435 | "(only possible in ACL for DATA)", acl_wherenames[where]); |
| 1436 | return ERROR; |
| 1437 | } |
| 1438 | verify_header_sender = TRUE; |
| 1439 | } |
| 1440 | |
| 1441 | /* Otherwise, first item in verify argument must be "sender" or "recipient". |
| 1442 | In the case of a sender, this can optionally be followed by an address to use |
| 1443 | in place of the actual sender (rare special-case requirement). */ |
| 1444 | |
| 1445 | else if (strncmpic(ss, US"sender", 6) == 0) |
| 1446 | { |
| 1447 | uschar *s = ss + 6; |
| 1448 | if (where > ACL_WHERE_NOTSMTP) |
| 1449 | { |
| 1450 | *log_msgptr = string_sprintf("cannot verify sender in ACL for %s " |
| 1451 | "(only possible for MAIL, RCPT, PREDATA, or DATA)", |
| 1452 | acl_wherenames[where]); |
| 1453 | return ERROR; |
| 1454 | } |
| 1455 | if (*s == 0) |
| 1456 | verify_sender_address = sender_address; |
| 1457 | else |
| 1458 | { |
| 1459 | while (isspace(*s)) s++; |
| 1460 | if (*s++ != '=') goto BAD_VERIFY; |
| 1461 | while (isspace(*s)) s++; |
| 1462 | verify_sender_address = string_copy(s); |
| 1463 | } |
| 1464 | } |
| 1465 | else |
| 1466 | { |
| 1467 | if (strcmpic(ss, US"recipient") != 0) goto BAD_VERIFY; |
| 1468 | if (addr == NULL) |
| 1469 | { |
| 1470 | *log_msgptr = string_sprintf("cannot verify recipient in ACL for %s " |
| 1471 | "(only possible for RCPT)", acl_wherenames[where]); |
| 1472 | return ERROR; |
| 1473 | } |
| 1474 | } |
| 1475 | |
| 1476 | /* Remaining items are optional; they apply to sender and recipient |
| 1477 | verification, including "header sender" verification. */ |
| 1478 | |
| 1479 | while ((ss = string_nextinlist(&list, &sep, big_buffer, big_buffer_size)) |
| 1480 | != NULL) |
| 1481 | { |
| 1482 | if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE; |
| 1483 | else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE; |
| 1484 | else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE; |
| 1485 | |
| 1486 | /* These two old options are left for backwards compatibility */ |
| 1487 | |
| 1488 | else if (strcmpic(ss, US"callout_defer_ok") == 0) |
| 1489 | { |
| 1490 | callout_defer_ok = TRUE; |
| 1491 | if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT; |
| 1492 | } |
| 1493 | |
| 1494 | else if (strcmpic(ss, US"check_postmaster") == 0) |
| 1495 | { |
| 1496 | pm_mailfrom = US""; |
| 1497 | if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT; |
| 1498 | } |
| 1499 | |
| 1500 | /* The callout option has a number of sub-options, comma separated */ |
| 1501 | |
| 1502 | else if (strncmpic(ss, US"callout", 7) == 0) |
| 1503 | { |
| 1504 | callout = CALLOUT_TIMEOUT_DEFAULT; |
| 1505 | ss += 7; |
| 1506 | if (*ss != 0) |
| 1507 | { |
| 1508 | while (isspace(*ss)) ss++; |
| 1509 | if (*ss++ == '=') |
| 1510 | { |
| 1511 | int optsep = ','; |
| 1512 | uschar *opt; |
| 1513 | uschar buffer[256]; |
| 1514 | while (isspace(*ss)) ss++; |
| 1515 | |
| 1516 | /* This callout option handling code has become a mess as new options |
| 1517 | have been added in an ad hoc manner. It should be tidied up into some |
| 1518 | kind of table-driven thing. */ |
| 1519 | |
| 1520 | while ((opt = string_nextinlist(&ss, &optsep, buffer, sizeof(buffer))) |
| 1521 | != NULL) |
| 1522 | { |
| 1523 | if (strcmpic(opt, US"defer_ok") == 0) callout_defer_ok = TRUE; |
| 1524 | else if (strcmpic(opt, US"no_cache") == 0) |
| 1525 | verify_options |= vopt_callout_no_cache; |
| 1526 | else if (strcmpic(opt, US"random") == 0) |
| 1527 | verify_options |= vopt_callout_random; |
| 1528 | else if (strcmpic(opt, US"use_sender") == 0) |
| 1529 | verify_options |= vopt_callout_recipsender; |
| 1530 | else if (strcmpic(opt, US"use_postmaster") == 0) |
| 1531 | verify_options |= vopt_callout_recippmaster; |
| 1532 | else if (strcmpic(opt, US"postmaster") == 0) pm_mailfrom = US""; |
| 1533 | else if (strcmpic(opt, US"fullpostmaster") == 0) |
| 1534 | { |
| 1535 | pm_mailfrom = US""; |
| 1536 | verify_options |= vopt_callout_fullpm; |
| 1537 | } |
| 1538 | |
| 1539 | else if (strncmpic(opt, US"mailfrom", 8) == 0) |
| 1540 | { |
| 1541 | if (!verify_header_sender) |
| 1542 | { |
| 1543 | *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a " |
| 1544 | "callout option only for verify=header_sender (detected in ACL " |
| 1545 | "condition \"%s\")", arg); |
| 1546 | return ERROR; |
| 1547 | } |
| 1548 | opt += 8; |
| 1549 | while (isspace(*opt)) opt++; |
| 1550 | if (*opt++ != '=') |
| 1551 | { |
| 1552 | *log_msgptr = string_sprintf("'=' expected after " |
| 1553 | "\"mailfrom\" in ACL condition \"%s\"", arg); |
| 1554 | return ERROR; |
| 1555 | } |
| 1556 | while (isspace(*opt)) opt++; |
| 1557 | se_mailfrom = string_copy(opt); |
| 1558 | } |
| 1559 | |
| 1560 | else if (strncmpic(opt, US"postmaster_mailfrom", 19) == 0) |
| 1561 | { |
| 1562 | opt += 19; |
| 1563 | while (isspace(*opt)) opt++; |
| 1564 | if (*opt++ != '=') |
| 1565 | { |
| 1566 | *log_msgptr = string_sprintf("'=' expected after " |
| 1567 | "\"postmaster_mailfrom\" in ACL condition \"%s\"", arg); |
| 1568 | return ERROR; |
| 1569 | } |
| 1570 | while (isspace(*opt)) opt++; |
| 1571 | pm_mailfrom = string_copy(opt); |
| 1572 | } |
| 1573 | |
| 1574 | else if (strncmpic(opt, US"maxwait", 7) == 0) |
| 1575 | { |
| 1576 | opt += 7; |
| 1577 | while (isspace(*opt)) opt++; |
| 1578 | if (*opt++ != '=') |
| 1579 | { |
| 1580 | *log_msgptr = string_sprintf("'=' expected after \"maxwait\" in " |
| 1581 | "ACL condition \"%s\"", arg); |
| 1582 | return ERROR; |
| 1583 | } |
| 1584 | while (isspace(*opt)) opt++; |
| 1585 | callout_overall = readconf_readtime(opt, 0, FALSE); |
| 1586 | if (callout_overall < 0) |
| 1587 | { |
| 1588 | *log_msgptr = string_sprintf("bad time value in ACL condition " |
| 1589 | "\"verify %s\"", arg); |
| 1590 | return ERROR; |
| 1591 | } |
| 1592 | } |
| 1593 | else if (strncmpic(opt, US"connect", 7) == 0) |
| 1594 | { |
| 1595 | opt += 7; |
| 1596 | while (isspace(*opt)) opt++; |
| 1597 | if (*opt++ != '=') |
| 1598 | { |
| 1599 | *log_msgptr = string_sprintf("'=' expected after " |
| 1600 | "\"callout_overaall\" in ACL condition \"%s\"", arg); |
| 1601 | return ERROR; |
| 1602 | } |
| 1603 | while (isspace(*opt)) opt++; |
| 1604 | callout_connect = readconf_readtime(opt, 0, FALSE); |
| 1605 | if (callout_connect < 0) |
| 1606 | { |
| 1607 | *log_msgptr = string_sprintf("bad time value in ACL condition " |
| 1608 | "\"verify %s\"", arg); |
| 1609 | return ERROR; |
| 1610 | } |
| 1611 | } |
| 1612 | else /* Plain time is callout connect/command timeout */ |
| 1613 | { |
| 1614 | callout = readconf_readtime(opt, 0, FALSE); |
| 1615 | if (callout < 0) |
| 1616 | { |
| 1617 | *log_msgptr = string_sprintf("bad time value in ACL condition " |
| 1618 | "\"verify %s\"", arg); |
| 1619 | return ERROR; |
| 1620 | } |
| 1621 | } |
| 1622 | } |
| 1623 | } |
| 1624 | else |
| 1625 | { |
| 1626 | *log_msgptr = string_sprintf("'=' expected after \"callout\" in " |
| 1627 | "ACL condition \"%s\"", arg); |
| 1628 | return ERROR; |
| 1629 | } |
| 1630 | } |
| 1631 | } |
| 1632 | |
| 1633 | /* Option not recognized */ |
| 1634 | |
| 1635 | else |
| 1636 | { |
| 1637 | *log_msgptr = string_sprintf("unknown option \"%s\" in ACL " |
| 1638 | "condition \"verify %s\"", ss, arg); |
| 1639 | return ERROR; |
| 1640 | } |
| 1641 | } |
| 1642 | |
| 1643 | if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) == |
| 1644 | (vopt_callout_recipsender|vopt_callout_recippmaster)) |
| 1645 | { |
| 1646 | *log_msgptr = US"only one of use_sender and use_postmaster can be set " |
| 1647 | "for a recipient callout"; |
| 1648 | return ERROR; |
| 1649 | } |
| 1650 | |
| 1651 | /* Handle sender-in-header verification. Default the user message to the log |
| 1652 | message if giving out verification details. */ |
| 1653 | |
| 1654 | if (verify_header_sender) |
| 1655 | { |
| 1656 | int verrno; |
| 1657 | rc = verify_check_header_address(user_msgptr, log_msgptr, callout, |
| 1658 | callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options, |
| 1659 | &verrno); |
| 1660 | if (rc != OK) |
| 1661 | { |
| 1662 | *basic_errno = verrno; |
| 1663 | if (smtp_return_error_details) |
| 1664 | { |
| 1665 | if (*user_msgptr == NULL && *log_msgptr != NULL) |
| 1666 | *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr); |
| 1667 | if (rc == DEFER) acl_temp_details = TRUE; |
| 1668 | } |
| 1669 | } |
| 1670 | } |
| 1671 | |
| 1672 | /* Handle a sender address. The default is to verify *the* sender address, but |
| 1673 | optionally a different address can be given, for special requirements. If the |
| 1674 | address is empty, we are dealing with a bounce message that has no sender, so |
| 1675 | we cannot do any checking. If the real sender address gets rewritten during |
| 1676 | verification (e.g. DNS widening), set the flag to stop it being rewritten again |
| 1677 | during message reception. |
| 1678 | |
| 1679 | A list of verified "sender" addresses is kept to try to avoid doing to much |
| 1680 | work repetitively when there are multiple recipients in a message and they all |
| 1681 | require sender verification. However, when callouts are involved, it gets too |
| 1682 | complicated because different recipients may require different callout options. |
| 1683 | Therefore, we always do a full sender verify when any kind of callout is |
| 1684 | specified. Caching elsewhere, for instance in the DNS resolver and in the |
| 1685 | callout handling, should ensure that this is not terribly inefficient. */ |
| 1686 | |
| 1687 | else if (verify_sender_address != NULL) |
| 1688 | { |
| 1689 | if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) |
| 1690 | != 0) |
| 1691 | { |
| 1692 | *log_msgptr = US"use_sender or use_postmaster cannot be used for a " |
| 1693 | "sender verify callout"; |
| 1694 | return ERROR; |
| 1695 | } |
| 1696 | |
| 1697 | sender_vaddr = verify_checked_sender(verify_sender_address); |
| 1698 | if (sender_vaddr != NULL && /* Previously checked */ |
| 1699 | callout <= 0) /* No callout needed this time */ |
| 1700 | { |
| 1701 | /* If the "routed" flag is set, it means that routing worked before, so |
| 1702 | this check can give OK (the saved return code value, if set, belongs to a |
| 1703 | callout that was done previously). If the "routed" flag is not set, routing |
| 1704 | must have failed, so we use the saved return code. */ |
| 1705 | |
| 1706 | if (testflag(sender_vaddr, af_verify_routed)) rc = OK; else |
| 1707 | { |
| 1708 | rc = sender_vaddr->special_action; |
| 1709 | *basic_errno = sender_vaddr->basic_errno; |
| 1710 | } |
| 1711 | HDEBUG(D_acl) debug_printf("using cached sender verify result\n"); |
| 1712 | } |
| 1713 | |
| 1714 | /* Do a new verification, and cache the result. The cache is used to avoid |
| 1715 | verifying the sender multiple times for multiple RCPTs when callouts are not |
| 1716 | specified (see comments above). |
| 1717 | |
| 1718 | The cache is also used on failure to give details in response to the first |
| 1719 | RCPT that gets bounced for this reason. However, this can be suppressed by |
| 1720 | the no_details option, which sets the flag that says "this detail has already |
| 1721 | been sent". The cache normally contains just one address, but there may be |
| 1722 | more in esoteric circumstances. */ |
| 1723 | |
| 1724 | else |
| 1725 | { |
| 1726 | BOOL routed = TRUE; |
| 1727 | uschar *save_address_data = deliver_address_data; |
| 1728 | |
| 1729 | sender_vaddr = deliver_make_addr(verify_sender_address, TRUE); |
| 1730 | if (no_details) setflag(sender_vaddr, af_sverify_told); |
| 1731 | if (verify_sender_address[0] != 0) |
| 1732 | { |
| 1733 | /* If this is the real sender address, save the unrewritten version |
| 1734 | for use later in receive. Otherwise, set a flag so that rewriting the |
| 1735 | sender in verify_address() does not update sender_address. */ |
| 1736 | |
| 1737 | if (verify_sender_address == sender_address) |
| 1738 | sender_address_unrewritten = sender_address; |
| 1739 | else |
| 1740 | verify_options |= vopt_fake_sender; |
| 1741 | |
| 1742 | if (success_on_redirect) |
| 1743 | verify_options |= vopt_success_on_redirect; |
| 1744 | |
| 1745 | /* The recipient, qualify, and expn options are never set in |
| 1746 | verify_options. */ |
| 1747 | |
| 1748 | rc = verify_address(sender_vaddr, NULL, verify_options, callout, |
| 1749 | callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed); |
| 1750 | |
| 1751 | HDEBUG(D_acl) debug_printf("----------- end verify ------------\n"); |
| 1752 | |
| 1753 | if (rc == OK) |
| 1754 | { |
| 1755 | if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0) |
| 1756 | { |
| 1757 | DEBUG(D_acl) debug_printf("sender %s verified ok as %s\n", |
| 1758 | verify_sender_address, sender_vaddr->address); |
| 1759 | } |
| 1760 | else |
| 1761 | { |
| 1762 | DEBUG(D_acl) debug_printf("sender %s verified ok\n", |
| 1763 | verify_sender_address); |
| 1764 | } |
| 1765 | } |
| 1766 | else *basic_errno = sender_vaddr->basic_errno; |
| 1767 | } |
| 1768 | else rc = OK; /* Null sender */ |
| 1769 | |
| 1770 | /* Cache the result code */ |
| 1771 | |
| 1772 | if (routed) setflag(sender_vaddr, af_verify_routed); |
| 1773 | if (callout > 0) setflag(sender_vaddr, af_verify_callout); |
| 1774 | sender_vaddr->special_action = rc; |
| 1775 | sender_vaddr->next = sender_verified_list; |
| 1776 | sender_verified_list = sender_vaddr; |
| 1777 | |
| 1778 | /* Restore the recipient address data, which might have been clobbered by |
| 1779 | the sender verification. */ |
| 1780 | |
| 1781 | deliver_address_data = save_address_data; |
| 1782 | } |
| 1783 | |
| 1784 | /* Put the sender address_data value into $sender_address_data */ |
| 1785 | |
| 1786 | sender_address_data = sender_vaddr->p.address_data; |
| 1787 | } |
| 1788 | |
| 1789 | /* A recipient address just gets a straightforward verify; again we must handle |
| 1790 | the DEFER overrides. */ |
| 1791 | |
| 1792 | else |
| 1793 | { |
| 1794 | address_item addr2; |
| 1795 | |
| 1796 | if (success_on_redirect) |
| 1797 | verify_options |= vopt_success_on_redirect; |
| 1798 | |
| 1799 | /* We must use a copy of the address for verification, because it might |
| 1800 | get rewritten. */ |
| 1801 | |
| 1802 | addr2 = *addr; |
| 1803 | rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout, |
| 1804 | callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL); |
| 1805 | HDEBUG(D_acl) debug_printf("----------- end verify ------------\n"); |
| 1806 | |
| 1807 | *log_msgptr = addr2.message; |
| 1808 | *user_msgptr = (addr2.user_message != NULL)? |
| 1809 | addr2.user_message : addr2.message; |
| 1810 | *basic_errno = addr2.basic_errno; |
| 1811 | |
| 1812 | /* Make $address_data visible */ |
| 1813 | deliver_address_data = addr2.p.address_data; |
| 1814 | } |
| 1815 | |
| 1816 | /* We have a result from the relevant test. Handle defer overrides first. */ |
| 1817 | |
| 1818 | if (rc == DEFER && (defer_ok || |
| 1819 | (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER))) |
| 1820 | { |
| 1821 | HDEBUG(D_acl) debug_printf("verify defer overridden by %s\n", |
| 1822 | defer_ok? "defer_ok" : "callout_defer_ok"); |
| 1823 | rc = OK; |
| 1824 | } |
| 1825 | |
| 1826 | /* If we've failed a sender, set up a recipient message, and point |
| 1827 | sender_verified_failed to the address item that actually failed. */ |
| 1828 | |
| 1829 | if (rc != OK && verify_sender_address != NULL) |
| 1830 | { |
| 1831 | if (rc != DEFER) |
| 1832 | { |
| 1833 | *log_msgptr = *user_msgptr = US"Sender verify failed"; |
| 1834 | } |
| 1835 | else if (*basic_errno != ERRNO_CALLOUTDEFER) |
| 1836 | { |
| 1837 | *log_msgptr = *user_msgptr = US"Could not complete sender verify"; |
| 1838 | } |
| 1839 | else |
| 1840 | { |
| 1841 | *log_msgptr = US"Could not complete sender verify callout"; |
| 1842 | *user_msgptr = smtp_return_error_details? sender_vaddr->user_message : |
| 1843 | *log_msgptr; |
| 1844 | } |
| 1845 | |
| 1846 | sender_verified_failed = sender_vaddr; |
| 1847 | } |
| 1848 | |
| 1849 | /* Verifying an address messes up the values of $domain and $local_part, |
| 1850 | so reset them before returning if this is a RCPT ACL. */ |
| 1851 | |
| 1852 | if (addr != NULL) |
| 1853 | { |
| 1854 | deliver_domain = addr->domain; |
| 1855 | deliver_localpart = addr->local_part; |
| 1856 | } |
| 1857 | return rc; |
| 1858 | |
| 1859 | /* Syntax errors in the verify argument come here. */ |
| 1860 | |
| 1861 | BAD_VERIFY: |
| 1862 | *log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", " |
| 1863 | "\"helo\", \"header_syntax\", \"header_sender\" or " |
| 1864 | "\"reverse_host_lookup\" at start of ACL condition " |
| 1865 | "\"verify %s\"", arg); |
| 1866 | return ERROR; |
| 1867 | |
| 1868 | /* Options supplied when not allowed come here */ |
| 1869 | |
| 1870 | NO_OPTIONS: |
| 1871 | *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" " |
| 1872 | "(this verify item has no options)", arg); |
| 1873 | return ERROR; |
| 1874 | } |
| 1875 | |
| 1876 | |
| 1877 | |
| 1878 | |
| 1879 | /************************************************* |
| 1880 | * Check argument for control= modifier * |
| 1881 | *************************************************/ |
| 1882 | |
| 1883 | /* Called from acl_check_condition() below |
| 1884 | |
| 1885 | Arguments: |
| 1886 | arg the argument string for control= |
| 1887 | pptr set to point to the terminating character |
| 1888 | where which ACL we are in |
| 1889 | log_msgptr for error messages |
| 1890 | |
| 1891 | Returns: CONTROL_xxx value |
| 1892 | */ |
| 1893 | |
| 1894 | static int |
| 1895 | decode_control(uschar *arg, uschar **pptr, int where, uschar **log_msgptr) |
| 1896 | { |
| 1897 | int len; |
| 1898 | control_def *d; |
| 1899 | |
| 1900 | for (d = controls_list; |
| 1901 | d < controls_list + sizeof(controls_list)/sizeof(control_def); |
| 1902 | d++) |
| 1903 | { |
| 1904 | len = Ustrlen(d->name); |
| 1905 | if (Ustrncmp(d->name, arg, len) == 0) break; |
| 1906 | } |
| 1907 | |
| 1908 | if (d >= controls_list + sizeof(controls_list)/sizeof(control_def) || |
| 1909 | (arg[len] != 0 && (!d->has_option || arg[len] != '/'))) |
| 1910 | { |
| 1911 | *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg); |
| 1912 | return CONTROL_ERROR; |
| 1913 | } |
| 1914 | |
| 1915 | *pptr = arg + len; |
| 1916 | return d->value; |
| 1917 | } |
| 1918 | |
| 1919 | |
| 1920 | |
| 1921 | /************************************************* |
| 1922 | * Handle rate limiting * |
| 1923 | *************************************************/ |
| 1924 | |
| 1925 | /* Called by acl_check_condition() below to calculate the result |
| 1926 | of the ACL ratelimit condition. |
| 1927 | |
| 1928 | Note that the return value might be slightly unexpected: if the |
| 1929 | sender's rate is above the limit then the result is OK. This is |
| 1930 | similar to the dnslists condition, and is so that you can write |
| 1931 | ACL clauses like: defer ratelimit = 15 / 1h |
| 1932 | |
| 1933 | Arguments: |
| 1934 | arg the option string for ratelimit= |
| 1935 | log_msgptr for error messages |
| 1936 | |
| 1937 | Returns: OK - Sender's rate is above limit |
| 1938 | FAIL - Sender's rate is below limit |
| 1939 | DEFER - Problem opening ratelimit database |
| 1940 | ERROR - Syntax error in options. |
| 1941 | */ |
| 1942 | |
| 1943 | static int |
| 1944 | acl_ratelimit(uschar *arg, uschar **log_msgptr) |
| 1945 | { |
| 1946 | double limit, period; |
| 1947 | uschar *ss, *key; |
| 1948 | int sep = '/'; |
| 1949 | BOOL have_key = FALSE, leaky = FALSE, strict = FALSE; |
| 1950 | BOOL per_byte = FALSE, per_cmd = FALSE, per_conn = FALSE, per_mail = FALSE; |
| 1951 | int old_pool, rc; |
| 1952 | tree_node **anchor, *t; |
| 1953 | open_db dbblock, *dbm; |
| 1954 | dbdata_ratelimit *dbd; |
| 1955 | struct timeval tv; |
| 1956 | |
| 1957 | /* Parse the first two options and record their values in expansion |
| 1958 | variables. These variables allow the configuration to have informative |
| 1959 | error messages based on rate limits obtained from a table lookup. */ |
| 1960 | |
| 1961 | /* First is the maximum number of messages per period and maximum burst |
| 1962 | size, which must be greater than or equal to zero. Zero is useful for |
| 1963 | rate measurement as opposed to rate limiting. */ |
| 1964 | |
| 1965 | sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0); |
| 1966 | if (sender_rate_limit == NULL) |
| 1967 | limit = -1.0; |
| 1968 | else |
| 1969 | { |
| 1970 | limit = Ustrtod(sender_rate_limit, &ss); |
| 1971 | if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; } |
| 1972 | else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; } |
| 1973 | else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; } |
| 1974 | } |
| 1975 | if (limit < 0.0 || *ss != 0) |
| 1976 | { |
| 1977 | *log_msgptr = string_sprintf("syntax error in argument for " |
| 1978 | "\"ratelimit\" condition: \"%s\" is not a positive number", |
| 1979 | sender_rate_limit); |
| 1980 | return ERROR; |
| 1981 | } |
| 1982 | |
| 1983 | /* We use the rest of the argument list following the limit as the |
| 1984 | lookup key, because it doesn't make sense to use the same stored data |
| 1985 | if the period or options are different. */ |
| 1986 | |
| 1987 | key = arg; |
| 1988 | |
| 1989 | /* Second is the rate measurement period and exponential smoothing time |
| 1990 | constant. This must be strictly greater than zero, because zero leads to |
| 1991 | run-time division errors. */ |
| 1992 | |
| 1993 | sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0); |
| 1994 | if (sender_rate_period == NULL) period = -1.0; |
| 1995 | else period = readconf_readtime(sender_rate_period, 0, FALSE); |
| 1996 | if (period <= 0.0) |
| 1997 | { |
| 1998 | *log_msgptr = string_sprintf("syntax error in argument for " |
| 1999 | "\"ratelimit\" condition: \"%s\" is not a time value", |
| 2000 | sender_rate_period); |
| 2001 | return ERROR; |
| 2002 | } |
| 2003 | |
| 2004 | /* Parse the other options. Should we check if the per_* options are being |
| 2005 | used in ACLs where they don't make sense, e.g. per_mail in the connect ACL? */ |
| 2006 | |
| 2007 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) |
| 2008 | != NULL) |
| 2009 | { |
| 2010 | if (strcmpic(ss, US"leaky") == 0) leaky = TRUE; |
| 2011 | else if (strcmpic(ss, US"strict") == 0) strict = TRUE; |
| 2012 | else if (strcmpic(ss, US"per_byte") == 0) per_byte = TRUE; |
| 2013 | else if (strcmpic(ss, US"per_cmd") == 0) per_cmd = TRUE; |
| 2014 | else if (strcmpic(ss, US"per_conn") == 0) per_conn = TRUE; |
| 2015 | else if (strcmpic(ss, US"per_mail") == 0) per_mail = TRUE; |
| 2016 | else if (strcmpic(ss, US"per_rcpt") == 0) per_cmd = TRUE; /* alias */ |
| 2017 | else have_key = TRUE; |
| 2018 | } |
| 2019 | if (leaky + strict > 1 || per_byte + per_cmd + per_conn + per_mail > 1) |
| 2020 | { |
| 2021 | *log_msgptr = US"conflicting options for \"ratelimit\" condition"; |
| 2022 | return ERROR; |
| 2023 | } |
| 2024 | |
| 2025 | /* Default option values */ |
| 2026 | if (!strict) leaky = TRUE; |
| 2027 | if (!per_byte && !per_cmd && !per_conn) per_mail = TRUE; |
| 2028 | |
| 2029 | /* If there is no explicit key, use the sender_host_address. If there is no |
| 2030 | sender_host_address (e.g. -bs or acl_not_smtp) then we simply omit it. */ |
| 2031 | |
| 2032 | if (!have_key && sender_host_address != NULL) |
| 2033 | key = string_sprintf("%s / %s", key, sender_host_address); |
| 2034 | |
| 2035 | HDEBUG(D_acl) debug_printf("ratelimit condition limit=%.0f period=%.0f key=%s\n", |
| 2036 | limit, period, key); |
| 2037 | |
| 2038 | /* See if we have already computed the rate by looking in the relevant tree. For |
| 2039 | per-connection rate limiting, store tree nodes and dbdata in the permanent pool |
| 2040 | so that they survive across resets. */ |
| 2041 | |
| 2042 | anchor = NULL; |
| 2043 | old_pool = store_pool; |
| 2044 | |
| 2045 | if (per_conn) |
| 2046 | { |
| 2047 | anchor = &ratelimiters_conn; |
| 2048 | store_pool = POOL_PERM; |
| 2049 | } |
| 2050 | else if (per_mail || per_byte) |
| 2051 | anchor = &ratelimiters_mail; |
| 2052 | else if (per_cmd) |
| 2053 | anchor = &ratelimiters_cmd; |
| 2054 | |
| 2055 | if (anchor != NULL && (t = tree_search(*anchor, key)) != NULL) |
| 2056 | { |
| 2057 | dbd = t->data.ptr; |
| 2058 | /* The following few lines duplicate some of the code below. */ |
| 2059 | if (dbd->rate < limit) rc = FAIL; |
| 2060 | else rc = OK; |
| 2061 | store_pool = old_pool; |
| 2062 | sender_rate = string_sprintf("%.1f", dbd->rate); |
| 2063 | HDEBUG(D_acl) |
| 2064 | debug_printf("ratelimit found pre-computed rate %s\n", sender_rate); |
| 2065 | return rc; |
| 2066 | } |
| 2067 | |
| 2068 | /* We aren't using a pre-computed rate, so get a previously recorded |
| 2069 | rate from the database, update it, and write it back. If there's no |
| 2070 | previous rate for this key, create one. */ |
| 2071 | |
| 2072 | dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE); |
| 2073 | if (dbm == NULL) |
| 2074 | { |
| 2075 | store_pool = old_pool; |
| 2076 | sender_rate = NULL; |
| 2077 | HDEBUG(D_acl) debug_printf("ratelimit database not available\n"); |
| 2078 | *log_msgptr = US"ratelimit database not available"; |
| 2079 | return DEFER; |
| 2080 | } |
| 2081 | dbd = dbfn_read(dbm, key); |
| 2082 | |
| 2083 | gettimeofday(&tv, NULL); |
| 2084 | |
| 2085 | if (dbd == NULL) |
| 2086 | { |
| 2087 | HDEBUG(D_acl) debug_printf("ratelimit initializing new key's data\n"); |
| 2088 | dbd = store_get(sizeof(dbdata_ratelimit)); |
| 2089 | dbd->time_stamp = tv.tv_sec; |
| 2090 | dbd->time_usec = tv.tv_usec; |
| 2091 | dbd->rate = 0.0; |
| 2092 | } |
| 2093 | else |
| 2094 | { |
| 2095 | /* The smoothed rate is computed using an exponentially weighted moving |
| 2096 | average adjusted for variable sampling intervals. The standard EWMA for |
| 2097 | a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1) |
| 2098 | where f() is the measured value and f'() is the smoothed value. |
| 2099 | |
| 2100 | Old data decays out of the smoothed value exponentially, such that data n |
| 2101 | samples old is multiplied by a^n. The exponential decay time constant p |
| 2102 | is defined such that data p samples old is multiplied by 1/e, which means |
| 2103 | that a = exp(-1/p). We can maintain the same time constant for a variable |
| 2104 | sampling interval i by using a = exp(-i/p). |
| 2105 | |
| 2106 | The rate we are measuring is messages per period, suitable for directly |
| 2107 | comparing with the limit. The average rate between now and the previous |
| 2108 | message is period / interval, which we feed into the EWMA as the sample. |
| 2109 | |
| 2110 | It turns out that the number of messages required for the smoothed rate |
| 2111 | to reach the limit when they are sent in a burst is equal to the limit. |
| 2112 | This can be seen by analysing the value of the smoothed rate after N |
| 2113 | messages sent at even intervals. Let k = (1 - a) * p/i |
| 2114 | |
| 2115 | rate_1 = (1 - a) * p/i + a * rate_0 |
| 2116 | = k + a * rate_0 |
| 2117 | rate_2 = k + a * rate_1 |
| 2118 | = k + a * k + a^2 * rate_0 |
| 2119 | rate_3 = k + a * k + a^2 * k + a^3 * rate_0 |
| 2120 | rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x) |
| 2121 | = rate_0 * a^N + k * (1 - a^N) / (1 - a) |
| 2122 | = rate_0 * a^N + p/i * (1 - a^N) |
| 2123 | |
| 2124 | When N is large, a^N -> 0 so rate_N -> p/i as desired. |
| 2125 | |
| 2126 | rate_N = p/i + (rate_0 - p/i) * a^N |
| 2127 | a^N = (rate_N - p/i) / (rate_0 - p/i) |
| 2128 | N * -i/p = log((rate_N - p/i) / (rate_0 - p/i)) |
| 2129 | N = p/i * log((rate_0 - p/i) / (rate_N - p/i)) |
| 2130 | |
| 2131 | Numerical analysis of the above equation, setting the computed rate to |
| 2132 | increase from rate_0 = 0 to rate_N = limit, shows that for large sending |
| 2133 | rates, p/i, the number of messages N = limit. So limit serves as both the |
| 2134 | maximum rate measured in messages per period, and the maximum number of |
| 2135 | messages that can be sent in a fast burst. */ |
| 2136 | |
| 2137 | double this_time = (double)tv.tv_sec |
| 2138 | + (double)tv.tv_usec / 1000000.0; |
| 2139 | double prev_time = (double)dbd->time_stamp |
| 2140 | + (double)dbd->time_usec / 1000000.0; |
| 2141 | double interval = this_time - prev_time; |
| 2142 | |
| 2143 | double i_over_p = interval / period; |
| 2144 | double a = exp(-i_over_p); |
| 2145 | |
| 2146 | /* We must avoid division by zero, and deal gracefully with the clock going |
| 2147 | backwards. If we blunder ahead when time is in reverse then the computed |
| 2148 | rate will become bogusly huge. Clamp i/p to a very small number instead. */ |
| 2149 | |
| 2150 | if (i_over_p <= 0.0) i_over_p = 1e-9; |
| 2151 | |
| 2152 | dbd->time_stamp = tv.tv_sec; |
| 2153 | dbd->time_usec = tv.tv_usec; |
| 2154 | |
| 2155 | /* If we are measuring the rate in bytes per period, multiply the |
| 2156 | measured rate by the message size. If we don't know the message size |
| 2157 | then it's safe to just use a value of zero and let the recorded rate |
| 2158 | decay as if nothing happened. */ |
| 2159 | |
| 2160 | if (per_byte) |
| 2161 | dbd->rate = (message_size < 0 ? 0.0 : (double)message_size) |
| 2162 | * (1 - a) / i_over_p + a * dbd->rate; |
| 2163 | else |
| 2164 | dbd->rate = (1 - a) / i_over_p + a * dbd->rate; |
| 2165 | } |
| 2166 | |
| 2167 | /* Clients sending at the limit are considered to be over the limit. This |
| 2168 | matters for edge cases such the first message sent by a client (which gets |
| 2169 | the initial rate of 0.0) when the rate limit is zero (i.e. the client should |
| 2170 | be completely blocked). */ |
| 2171 | |
| 2172 | if (dbd->rate < limit) rc = FAIL; |
| 2173 | else rc = OK; |
| 2174 | |
| 2175 | /* Update the state if the rate is low or if we are being strict. If we |
| 2176 | are in leaky mode and the sender's rate is too high, we do not update |
| 2177 | the recorded rate in order to avoid an over-aggressive sender's retry |
| 2178 | rate preventing them from getting any email through. */ |
| 2179 | |
| 2180 | if (rc == FAIL || !leaky) |
| 2181 | dbfn_write(dbm, key, dbd, sizeof(dbdata_ratelimit)); |
| 2182 | dbfn_close(dbm); |
| 2183 | |
| 2184 | /* Store the result in the tree for future reference, if necessary. */ |
| 2185 | |
| 2186 | if (anchor != NULL) |
| 2187 | { |
| 2188 | t = store_get(sizeof(tree_node) + Ustrlen(key)); |
| 2189 | t->data.ptr = dbd; |
| 2190 | Ustrcpy(t->name, key); |
| 2191 | (void)tree_insertnode(anchor, t); |
| 2192 | } |
| 2193 | |
| 2194 | /* We create the formatted version of the sender's rate very late in |
| 2195 | order to ensure that it is done using the correct storage pool. */ |
| 2196 | |
| 2197 | store_pool = old_pool; |
| 2198 | sender_rate = string_sprintf("%.1f", dbd->rate); |
| 2199 | |
| 2200 | HDEBUG(D_acl) |
| 2201 | debug_printf("ratelimit computed rate %s\n", sender_rate); |
| 2202 | |
| 2203 | return rc; |
| 2204 | } |
| 2205 | |
| 2206 | |
| 2207 | |
| 2208 | /************************************************* |
| 2209 | * Handle conditions/modifiers on an ACL item * |
| 2210 | *************************************************/ |
| 2211 | |
| 2212 | /* Called from acl_check() below. |
| 2213 | |
| 2214 | Arguments: |
| 2215 | verb ACL verb |
| 2216 | cb ACL condition block - if NULL, result is OK |
| 2217 | where where called from |
| 2218 | addr the address being checked for RCPT, or NULL |
| 2219 | level the nesting level |
| 2220 | epp pointer to pass back TRUE if "endpass" encountered |
| 2221 | (applies only to "accept" and "discard") |
| 2222 | user_msgptr user message pointer |
| 2223 | log_msgptr log message pointer |
| 2224 | basic_errno pointer to where to put verify error |
| 2225 | |
| 2226 | Returns: OK - all conditions are met |
| 2227 | DISCARD - an "acl" condition returned DISCARD - only allowed |
| 2228 | for "accept" or "discard" verbs |
| 2229 | FAIL - at least one condition fails |
| 2230 | FAIL_DROP - an "acl" condition returned FAIL_DROP |
| 2231 | DEFER - can't tell at the moment (typically, lookup defer, |
| 2232 | but can be temporary callout problem) |
| 2233 | ERROR - ERROR from nested ACL or expansion failure or other |
| 2234 | error |
| 2235 | */ |
| 2236 | |
| 2237 | static int |
| 2238 | acl_check_condition(int verb, acl_condition_block *cb, int where, |
| 2239 | address_item *addr, int level, BOOL *epp, uschar **user_msgptr, |
| 2240 | uschar **log_msgptr, int *basic_errno) |
| 2241 | { |
| 2242 | uschar *user_message = NULL; |
| 2243 | uschar *log_message = NULL; |
| 2244 | uschar *p; |
| 2245 | int rc = OK; |
| 2246 | #ifdef WITH_CONTENT_SCAN |
| 2247 | int sep = '/'; |
| 2248 | #endif |
| 2249 | |
| 2250 | for (; cb != NULL; cb = cb->next) |
| 2251 | { |
| 2252 | uschar *arg; |
| 2253 | int control_type; |
| 2254 | |
| 2255 | /* The message and log_message items set up messages to be used in |
| 2256 | case of rejection. They are expanded later. */ |
| 2257 | |
| 2258 | if (cb->type == ACLC_MESSAGE) |
| 2259 | { |
| 2260 | user_message = cb->arg; |
| 2261 | continue; |
| 2262 | } |
| 2263 | |
| 2264 | if (cb->type == ACLC_LOG_MESSAGE) |
| 2265 | { |
| 2266 | log_message = cb->arg; |
| 2267 | continue; |
| 2268 | } |
| 2269 | |
| 2270 | /* The endpass "condition" just sets a flag to show it occurred. This is |
| 2271 | checked at compile time to be on an "accept" or "discard" item. */ |
| 2272 | |
| 2273 | if (cb->type == ACLC_ENDPASS) |
| 2274 | { |
| 2275 | *epp = TRUE; |
| 2276 | continue; |
| 2277 | } |
| 2278 | |
| 2279 | /* For other conditions and modifiers, the argument is expanded now for some |
| 2280 | of them, but not for all, because expansion happens down in some lower level |
| 2281 | checking functions in some cases. */ |
| 2282 | |
| 2283 | if (cond_expand_at_top[cb->type]) |
| 2284 | { |
| 2285 | arg = expand_string(cb->arg); |
| 2286 | if (arg == NULL) |
| 2287 | { |
| 2288 | if (expand_string_forcedfail) continue; |
| 2289 | *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", |
| 2290 | cb->arg, expand_string_message); |
| 2291 | return search_find_defer? DEFER : ERROR; |
| 2292 | } |
| 2293 | } |
| 2294 | else arg = cb->arg; |
| 2295 | |
| 2296 | /* Show condition, and expanded condition if it's different */ |
| 2297 | |
| 2298 | HDEBUG(D_acl) |
| 2299 | { |
| 2300 | int lhswidth = 0; |
| 2301 | debug_printf("check %s%s %n", |
| 2302 | (!cond_modifiers[cb->type] && cb->u.negated)? "!":"", |
| 2303 | conditions[cb->type], &lhswidth); |
| 2304 | |
| 2305 | if (cb->type == ACLC_SET) |
| 2306 | { |
| 2307 | int n = cb->u.varnumber; |
| 2308 | int t = (n < ACL_C_MAX)? 'c' : 'm'; |
| 2309 | if (n >= ACL_C_MAX) n -= ACL_C_MAX; |
| 2310 | debug_printf("acl_%c%d ", t, n); |
| 2311 | lhswidth += 7; |
| 2312 | } |
| 2313 | |
| 2314 | debug_printf("= %s\n", cb->arg); |
| 2315 | |
| 2316 | if (arg != cb->arg) |
| 2317 | debug_printf("%.*s= %s\n", lhswidth, |
| 2318 | US" ", CS arg); |
| 2319 | } |
| 2320 | |
| 2321 | /* Check that this condition makes sense at this time */ |
| 2322 | |
| 2323 | if ((cond_forbids[cb->type] & (1 << where)) != 0) |
| 2324 | { |
| 2325 | *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL", |
| 2326 | cond_modifiers[cb->type]? "use" : "test", |
| 2327 | conditions[cb->type], acl_wherenames[where]); |
| 2328 | return ERROR; |
| 2329 | } |
| 2330 | |
| 2331 | /* Run the appropriate test for each condition, or take the appropriate |
| 2332 | action for the remaining modifiers. */ |
| 2333 | |
| 2334 | switch(cb->type) |
| 2335 | { |
| 2336 | /* A nested ACL that returns "discard" makes sense only for an "accept" or |
| 2337 | "discard" verb. */ |
| 2338 | |
| 2339 | case ACLC_ACL: |
| 2340 | rc = acl_check_internal(where, addr, arg, level+1, user_msgptr, log_msgptr); |
| 2341 | if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD) |
| 2342 | { |
| 2343 | *log_msgptr = string_sprintf("nested ACL returned \"discard\" for " |
| 2344 | "\"%s\" command (only allowed with \"accept\" or \"discard\")", |
| 2345 | verbs[verb]); |
| 2346 | return ERROR; |
| 2347 | } |
| 2348 | break; |
| 2349 | |
| 2350 | case ACLC_AUTHENTICATED: |
| 2351 | rc = (sender_host_authenticated == NULL)? FAIL : |
| 2352 | match_isinlist(sender_host_authenticated, &arg, 0, NULL, NULL, MCL_STRING, |
| 2353 | TRUE, NULL); |
| 2354 | break; |
| 2355 | |
| 2356 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 2357 | case ACLC_BMI_OPTIN: |
| 2358 | { |
| 2359 | int old_pool = store_pool; |
| 2360 | store_pool = POOL_PERM; |
| 2361 | bmi_current_optin = string_copy(arg); |
| 2362 | store_pool = old_pool; |
| 2363 | } |
| 2364 | break; |
| 2365 | #endif |
| 2366 | |
| 2367 | case ACLC_CONDITION: |
| 2368 | if (Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */ |
| 2369 | rc = (Uatoi(arg) == 0)? FAIL : OK; |
| 2370 | else |
| 2371 | rc = (strcmpic(arg, US"no") == 0 || |
| 2372 | strcmpic(arg, US"false") == 0)? FAIL : |
| 2373 | (strcmpic(arg, US"yes") == 0 || |
| 2374 | strcmpic(arg, US"true") == 0)? OK : DEFER; |
| 2375 | if (rc == DEFER) |
| 2376 | *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg); |
| 2377 | break; |
| 2378 | |
| 2379 | case ACLC_CONTROL: |
| 2380 | control_type = decode_control(arg, &p, where, log_msgptr); |
| 2381 | |
| 2382 | /* Check if this control makes sense at this time */ |
| 2383 | |
| 2384 | if ((control_forbids[control_type] & (1 << where)) != 0) |
| 2385 | { |
| 2386 | *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL", |
| 2387 | controls[control_type], acl_wherenames[where]); |
| 2388 | return ERROR; |
| 2389 | } |
| 2390 | |
| 2391 | switch(control_type) |
| 2392 | { |
| 2393 | #ifdef EXPERIMENTAL_BRIGHTMAIL |
| 2394 | case CONTROL_BMI_RUN: |
| 2395 | bmi_run = 1; |
| 2396 | break; |
| 2397 | #endif |
| 2398 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 2399 | case CONTROL_DK_VERIFY: |
| 2400 | dk_do_verify = 1; |
| 2401 | break; |
| 2402 | #endif |
| 2403 | case CONTROL_ERROR: |
| 2404 | return ERROR; |
| 2405 | |
| 2406 | case CONTROL_CASEFUL_LOCAL_PART: |
| 2407 | deliver_localpart = addr->cc_local_part; |
| 2408 | break; |
| 2409 | |
| 2410 | case CONTROL_CASELOWER_LOCAL_PART: |
| 2411 | deliver_localpart = addr->lc_local_part; |
| 2412 | break; |
| 2413 | |
| 2414 | case CONTROL_ENFORCE_SYNC: |
| 2415 | smtp_enforce_sync = TRUE; |
| 2416 | break; |
| 2417 | |
| 2418 | case CONTROL_NO_ENFORCE_SYNC: |
| 2419 | smtp_enforce_sync = FALSE; |
| 2420 | break; |
| 2421 | |
| 2422 | #ifdef WITH_CONTENT_SCAN |
| 2423 | case CONTROL_NO_MBOX_UNSPOOL: |
| 2424 | no_mbox_unspool = TRUE; |
| 2425 | break; |
| 2426 | #endif |
| 2427 | |
| 2428 | case CONTROL_NO_MULTILINE: |
| 2429 | no_multiline_responses = TRUE; |
| 2430 | break; |
| 2431 | |
| 2432 | case CONTROL_FAKEDEFER: |
| 2433 | case CONTROL_FAKEREJECT: |
| 2434 | fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL; |
| 2435 | if (*p == '/') |
| 2436 | { |
| 2437 | uschar *pp = p + 1; |
| 2438 | while (*pp != 0) pp++; |
| 2439 | fake_response_text = expand_string(string_copyn(p+1, pp-p-1)); |
| 2440 | p = pp; |
| 2441 | } |
| 2442 | else |
| 2443 | { |
| 2444 | /* Explicitly reset to default string */ |
| 2445 | fake_response_text = US"Your message has been rejected but is being kept for evaluation.\nIf it was a legitimate message, it may still be delivered to the target recipient(s)."; |
| 2446 | } |
| 2447 | break; |
| 2448 | |
| 2449 | case CONTROL_FREEZE: |
| 2450 | deliver_freeze = TRUE; |
| 2451 | deliver_frozen_at = time(NULL); |
| 2452 | break; |
| 2453 | |
| 2454 | case CONTROL_QUEUE_ONLY: |
| 2455 | queue_only_policy = TRUE; |
| 2456 | break; |
| 2457 | |
| 2458 | case CONTROL_SUBMISSION: |
| 2459 | originator_name = US""; |
| 2460 | submission_mode = TRUE; |
| 2461 | while (*p == '/') |
| 2462 | { |
| 2463 | if (Ustrncmp(p, "/sender_retain", 14) == 0) |
| 2464 | { |
| 2465 | p += 14; |
| 2466 | active_local_sender_retain = TRUE; |
| 2467 | active_local_from_check = FALSE; |
| 2468 | } |
| 2469 | else if (Ustrncmp(p, "/domain=", 8) == 0) |
| 2470 | { |
| 2471 | uschar *pp = p + 8; |
| 2472 | while (*pp != 0 && *pp != '/') pp++; |
| 2473 | submission_domain = string_copyn(p+8, pp-p-8); |
| 2474 | p = pp; |
| 2475 | } |
| 2476 | else if (Ustrncmp(p, "/name=", 6) == 0) |
| 2477 | { |
| 2478 | uschar *pp = p + 6; |
| 2479 | while (*pp != 0 && *pp != '/') pp++; |
| 2480 | originator_name = string_copy(parse_fix_phrase(p+6, pp-p-6, |
| 2481 | big_buffer, big_buffer_size)); |
| 2482 | p = pp; |
| 2483 | } |
| 2484 | else break; |
| 2485 | } |
| 2486 | if (*p != 0) |
| 2487 | { |
| 2488 | *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg); |
| 2489 | return ERROR; |
| 2490 | } |
| 2491 | break; |
| 2492 | } |
| 2493 | break; |
| 2494 | |
| 2495 | #ifdef WITH_CONTENT_SCAN |
| 2496 | case ACLC_DECODE: |
| 2497 | rc = mime_decode(&arg); |
| 2498 | break; |
| 2499 | #endif |
| 2500 | |
| 2501 | case ACLC_DELAY: |
| 2502 | { |
| 2503 | int delay = readconf_readtime(arg, 0, FALSE); |
| 2504 | if (delay < 0) |
| 2505 | { |
| 2506 | *log_msgptr = string_sprintf("syntax error in argument for \"delay\" " |
| 2507 | "modifier: \"%s\" is not a time value", arg); |
| 2508 | return ERROR; |
| 2509 | } |
| 2510 | else |
| 2511 | { |
| 2512 | HDEBUG(D_acl) debug_printf("delay modifier requests %d-second delay\n", |
| 2513 | delay); |
| 2514 | if (host_checking) |
| 2515 | { |
| 2516 | HDEBUG(D_acl) |
| 2517 | debug_printf("delay skipped in -bh checking mode\n"); |
| 2518 | } |
| 2519 | |
| 2520 | /* It appears to be impossible to detect that a TCP/IP connection has |
| 2521 | gone away without reading from it. This means that we cannot shorten |
| 2522 | the delay below if the client goes away, because we cannot discover |
| 2523 | that the client has closed its end of the connection. (The connection |
| 2524 | is actually in a half-closed state, waiting for the server to close its |
| 2525 | end.) It would be nice to be able to detect this state, so that the |
| 2526 | Exim process is not held up unnecessarily. However, it seems that we |
| 2527 | can't. The poll() function does not do the right thing, and in any case |
| 2528 | it is not always available. |
| 2529 | |
| 2530 | NOTE: If ever this state of affairs changes, remember that we may be |
| 2531 | dealing with stdin/stdout here, in addition to TCP/IP connections. |
| 2532 | Whatever is done must work in both cases. To detected the stdin/stdout |
| 2533 | case, check for smtp_in or smtp_out being NULL. */ |
| 2534 | |
| 2535 | else |
| 2536 | { |
| 2537 | while (delay > 0) delay = sleep(delay); |
| 2538 | } |
| 2539 | } |
| 2540 | } |
| 2541 | break; |
| 2542 | |
| 2543 | #ifdef WITH_OLD_DEMIME |
| 2544 | case ACLC_DEMIME: |
| 2545 | rc = demime(&arg); |
| 2546 | break; |
| 2547 | #endif |
| 2548 | |
| 2549 | #ifdef EXPERIMENTAL_DOMAINKEYS |
| 2550 | case ACLC_DK_DOMAIN_SOURCE: |
| 2551 | if (dk_verify_block == NULL) { rc = FAIL; break; }; |
| 2552 | /* check header source of domain against given string */ |
| 2553 | switch (dk_verify_block->address_source) { |
| 2554 | case DK_EXIM_ADDRESS_FROM_FROM: |
| 2555 | rc = match_isinlist(US"from", &arg, 0, NULL, |
| 2556 | NULL, MCL_STRING, TRUE, NULL); |
| 2557 | break; |
| 2558 | case DK_EXIM_ADDRESS_FROM_SENDER: |
| 2559 | rc = match_isinlist(US"sender", &arg, 0, NULL, |
| 2560 | NULL, MCL_STRING, TRUE, NULL); |
| 2561 | break; |
| 2562 | case DK_EXIM_ADDRESS_NONE: |
| 2563 | rc = match_isinlist(US"none", &arg, 0, NULL, |
| 2564 | NULL, MCL_STRING, TRUE, NULL); |
| 2565 | break; |
| 2566 | } |
| 2567 | break; |
| 2568 | case ACLC_DK_POLICY: |
| 2569 | if (dk_verify_block == NULL) { rc = FAIL; break; }; |
| 2570 | /* check policy against given string, default FAIL */ |
| 2571 | rc = FAIL; |
| 2572 | if (dk_verify_block->signsall) |
| 2573 | rc = match_isinlist(US"signsall", &arg, 0, NULL, |
| 2574 | NULL, MCL_STRING, TRUE, NULL); |
| 2575 | if (dk_verify_block->testing) |
| 2576 | rc = match_isinlist(US"testing", &arg, 0, NULL, |
| 2577 | NULL, MCL_STRING, TRUE, NULL); |
| 2578 | break; |
| 2579 | case ACLC_DK_SENDER_DOMAINS: |
| 2580 | if (dk_verify_block == NULL) { rc = FAIL; break; }; |
| 2581 | if (dk_verify_block->domain != NULL) |
| 2582 | rc = match_isinlist(dk_verify_block->domain, &arg, 0, &domainlist_anchor, |
| 2583 | NULL, MCL_DOMAIN, TRUE, NULL); |
| 2584 | else rc = FAIL; |
| 2585 | break; |
| 2586 | case ACLC_DK_SENDER_LOCAL_PARTS: |
| 2587 | if (dk_verify_block == NULL) { rc = FAIL; break; }; |
| 2588 | if (dk_verify_block->local_part != NULL) |
| 2589 | rc = match_isinlist(dk_verify_block->local_part, &arg, 0, &localpartlist_anchor, |
| 2590 | NULL, MCL_LOCALPART, TRUE, NULL); |
| 2591 | else rc = FAIL; |
| 2592 | break; |
| 2593 | case ACLC_DK_SENDERS: |
| 2594 | if (dk_verify_block == NULL) { rc = FAIL; break; }; |
| 2595 | if (dk_verify_block->address != NULL) |
| 2596 | rc = match_address_list(dk_verify_block->address, TRUE, TRUE, &arg, NULL, -1, 0, NULL); |
| 2597 | else rc = FAIL; |
| 2598 | break; |
| 2599 | case ACLC_DK_STATUS: |
| 2600 | if (dk_verify_block == NULL) { rc = FAIL; break; }; |
| 2601 | if (dk_verify_block->result > 0) { |
| 2602 | switch(dk_verify_block->result) { |
| 2603 | case DK_EXIM_RESULT_BAD_FORMAT: |
| 2604 | rc = match_isinlist(US"bad format", &arg, 0, NULL, |
| 2605 | NULL, MCL_STRING, TRUE, NULL); |
| 2606 | break; |
| 2607 | case DK_EXIM_RESULT_NO_KEY: |
| 2608 | rc = match_isinlist(US"no key", &arg, 0, NULL, |
| 2609 | NULL, MCL_STRING, TRUE, NULL); |
| 2610 | break; |
| 2611 | case DK_EXIM_RESULT_NO_SIGNATURE: |
| 2612 | rc = match_isinlist(US"no signature", &arg, 0, NULL, |
| 2613 | NULL, MCL_STRING, TRUE, NULL); |
| 2614 | break; |
| 2615 | case DK_EXIM_RESULT_REVOKED: |
| 2616 | rc = match_isinlist(US"revoked", &arg, 0, NULL, |
| 2617 | NULL, MCL_STRING, TRUE, NULL); |
| 2618 | break; |
| 2619 | case DK_EXIM_RESULT_NON_PARTICIPANT: |
| 2620 | rc = match_isinlist(US"non-participant", &arg, 0, NULL, |
| 2621 | NULL, MCL_STRING, TRUE, NULL); |
| 2622 | break; |
| 2623 | case DK_EXIM_RESULT_GOOD: |
| 2624 | rc = match_isinlist(US"good", &arg, 0, NULL, |
| 2625 | NULL, MCL_STRING, TRUE, NULL); |
| 2626 | break; |
| 2627 | case DK_EXIM_RESULT_BAD: |
| 2628 | rc = match_isinlist(US"bad", &arg, 0, NULL, |
| 2629 | NULL, MCL_STRING, TRUE, NULL); |
| 2630 | break; |
| 2631 | } |
| 2632 | } |
| 2633 | break; |
| 2634 | #endif |
| 2635 | |
| 2636 | case ACLC_DNSLISTS: |
| 2637 | rc = verify_check_dnsbl(&arg); |
| 2638 | break; |
| 2639 | |
| 2640 | case ACLC_DOMAINS: |
| 2641 | rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor, |
| 2642 | addr->domain_cache, MCL_DOMAIN, TRUE, &deliver_domain_data); |
| 2643 | break; |
| 2644 | |
| 2645 | /* The value in tls_cipher is the full cipher name, for example, |
| 2646 | TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the |
| 2647 | cipher names such as DES-CBC3-SHA. But program defensively. We don't know |
| 2648 | what may in practice come out of the SSL library - which at the time of |
| 2649 | writing is poorly documented. */ |
| 2650 | |
| 2651 | case ACLC_ENCRYPTED: |
| 2652 | if (tls_cipher == NULL) rc = FAIL; else |
| 2653 | { |
| 2654 | uschar *endcipher = NULL; |
| 2655 | uschar *cipher = Ustrchr(tls_cipher, ':'); |
| 2656 | if (cipher == NULL) cipher = tls_cipher; else |
| 2657 | { |
| 2658 | endcipher = Ustrchr(++cipher, ':'); |
| 2659 | if (endcipher != NULL) *endcipher = 0; |
| 2660 | } |
| 2661 | rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL); |
| 2662 | if (endcipher != NULL) *endcipher = ':'; |
| 2663 | } |
| 2664 | break; |
| 2665 | |
| 2666 | /* Use verify_check_this_host() instead of verify_check_host() so that |
| 2667 | we can pass over &host_data to catch any looked up data. Once it has been |
| 2668 | set, it retains its value so that it's still there if another ACL verb |
| 2669 | comes through here and uses the cache. However, we must put it into |
| 2670 | permanent store in case it is also expected to be used in a subsequent |
| 2671 | message in the same SMTP connection. */ |
| 2672 | |
| 2673 | case ACLC_HOSTS: |
| 2674 | rc = verify_check_this_host(&arg, sender_host_cache, NULL, |
| 2675 | (sender_host_address == NULL)? US"" : sender_host_address, &host_data); |
| 2676 | if (host_data != NULL) host_data = string_copy_malloc(host_data); |
| 2677 | break; |
| 2678 | |
| 2679 | case ACLC_LOCAL_PARTS: |
| 2680 | rc = match_isinlist(addr->cc_local_part, &arg, 0, |
| 2681 | &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE, |
| 2682 | &deliver_localpart_data); |
| 2683 | break; |
| 2684 | |
| 2685 | case ACLC_LOGWRITE: |
| 2686 | { |
| 2687 | int logbits = 0; |
| 2688 | uschar *s = arg; |
| 2689 | if (*s == ':') |
| 2690 | { |
| 2691 | s++; |
| 2692 | while (*s != ':') |
| 2693 | { |
| 2694 | if (Ustrncmp(s, "main", 4) == 0) |
| 2695 | { logbits |= LOG_MAIN; s += 4; } |
| 2696 | else if (Ustrncmp(s, "panic", 5) == 0) |
| 2697 | { logbits |= LOG_PANIC; s += 5; } |
| 2698 | else if (Ustrncmp(s, "reject", 6) == 0) |
| 2699 | { logbits |= LOG_REJECT; s += 6; } |
| 2700 | else |
| 2701 | { |
| 2702 | logbits = LOG_MAIN|LOG_PANIC; |
| 2703 | s = string_sprintf(":unknown log name in \"%s\" in " |
| 2704 | "\"logwrite\" in %s ACL", arg, acl_wherenames[where]); |
| 2705 | } |
| 2706 | if (*s == ',') s++; |
| 2707 | } |
| 2708 | s++; |
| 2709 | } |
| 2710 | while (isspace(*s)) s++; |
| 2711 | if (logbits == 0) logbits = LOG_MAIN; |
| 2712 | log_write(0, logbits, "%s", string_printing(s)); |
| 2713 | } |
| 2714 | break; |
| 2715 | |
| 2716 | #ifdef WITH_CONTENT_SCAN |
| 2717 | case ACLC_MALWARE: |
| 2718 | { |
| 2719 | /* Seperate the regular expression and any optional parameters. */ |
| 2720 | uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size); |
| 2721 | /* Run the malware backend. */ |
| 2722 | rc = malware(&ss); |
| 2723 | /* Modify return code based upon the existance of options. */ |
| 2724 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) |
| 2725 | != NULL) { |
| 2726 | if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER) |
| 2727 | { |
| 2728 | /* FAIL so that the message is passed to the next ACL */ |
| 2729 | rc = FAIL; |
| 2730 | } |
| 2731 | } |
| 2732 | } |
| 2733 | break; |
| 2734 | |
| 2735 | case ACLC_MIME_REGEX: |
| 2736 | rc = mime_regex(&arg); |
| 2737 | break; |
| 2738 | #endif |
| 2739 | |
| 2740 | case ACLC_RATELIMIT: |
| 2741 | rc = acl_ratelimit(arg, log_msgptr); |
| 2742 | break; |
| 2743 | |
| 2744 | case ACLC_RECIPIENTS: |
| 2745 | rc = match_address_list(addr->address, TRUE, TRUE, &arg, NULL, -1, 0, |
| 2746 | &recipient_data); |
| 2747 | break; |
| 2748 | |
| 2749 | #ifdef WITH_CONTENT_SCAN |
| 2750 | case ACLC_REGEX: |
| 2751 | rc = regex(&arg); |
| 2752 | break; |
| 2753 | #endif |
| 2754 | |
| 2755 | case ACLC_SENDER_DOMAINS: |
| 2756 | { |
| 2757 | uschar *sdomain; |
| 2758 | sdomain = Ustrrchr(sender_address, '@'); |
| 2759 | sdomain = (sdomain == NULL)? US"" : sdomain + 1; |
| 2760 | rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor, |
| 2761 | sender_domain_cache, MCL_DOMAIN, TRUE, NULL); |
| 2762 | } |
| 2763 | break; |
| 2764 | |
| 2765 | case ACLC_SENDERS: |
| 2766 | rc = match_address_list(sender_address, TRUE, TRUE, &arg, |
| 2767 | sender_address_cache, -1, 0, &sender_data); |
| 2768 | break; |
| 2769 | |
| 2770 | /* Connection variables must persist forever */ |
| 2771 | |
| 2772 | case ACLC_SET: |
| 2773 | { |
| 2774 | int old_pool = store_pool; |
| 2775 | if (cb->u.varnumber < ACL_C_MAX) store_pool = POOL_PERM; |
| 2776 | acl_var[cb->u.varnumber] = string_copy(arg); |
| 2777 | store_pool = old_pool; |
| 2778 | } |
| 2779 | break; |
| 2780 | |
| 2781 | #ifdef WITH_CONTENT_SCAN |
| 2782 | case ACLC_SPAM: |
| 2783 | { |
| 2784 | /* Seperate the regular expression and any optional parameters. */ |
| 2785 | uschar *ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size); |
| 2786 | /* Run the spam backend. */ |
| 2787 | rc = spam(&ss); |
| 2788 | /* Modify return code based upon the existance of options. */ |
| 2789 | while ((ss = string_nextinlist(&arg, &sep, big_buffer, big_buffer_size)) |
| 2790 | != NULL) { |
| 2791 | if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER) |
| 2792 | { |
| 2793 | /* FAIL so that the message is passed to the next ACL */ |
| 2794 | rc = FAIL; |
| 2795 | } |
| 2796 | } |
| 2797 | } |
| 2798 | break; |
| 2799 | #endif |
| 2800 | |
| 2801 | #ifdef EXPERIMENTAL_SPF |
| 2802 | case ACLC_SPF: |
| 2803 | rc = spf_process(&arg, sender_address); |
| 2804 | break; |
| 2805 | #endif |
| 2806 | |
| 2807 | /* If the verb is WARN, discard any user message from verification, because |
| 2808 | such messages are SMTP responses, not header additions. The latter come |
| 2809 | only from explicit "message" modifiers. However, put the user message into |
| 2810 | $acl_verify_message so it can be used in subsequent conditions or modifiers |
| 2811 | (until something changes it). */ |
| 2812 | |
| 2813 | case ACLC_VERIFY: |
| 2814 | rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno); |
| 2815 | acl_verify_message = *user_msgptr; |
| 2816 | if (verb == ACL_WARN) *user_msgptr = NULL; |
| 2817 | break; |
| 2818 | |
| 2819 | default: |
| 2820 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown " |
| 2821 | "condition %d", cb->type); |
| 2822 | break; |
| 2823 | } |
| 2824 | |
| 2825 | /* If a condition was negated, invert OK/FAIL. */ |
| 2826 | |
| 2827 | if (!cond_modifiers[cb->type] && cb->u.negated) |
| 2828 | { |
| 2829 | if (rc == OK) rc = FAIL; |
| 2830 | else if (rc == FAIL || rc == FAIL_DROP) rc = OK; |
| 2831 | } |
| 2832 | |
| 2833 | if (rc != OK) break; /* Conditions loop */ |
| 2834 | } |
| 2835 | |
| 2836 | |
| 2837 | /* If the result is the one for which "message" and/or "log_message" are used, |
| 2838 | handle the values of these options. Most verbs have but a single return for |
| 2839 | which the messages are relevant, but for "discard", it's useful to have the log |
| 2840 | message both when it succeeds and when it fails. Also, for an "accept" that |
| 2841 | appears in a QUIT ACL, we want to handle the user message. Since only "accept" |
| 2842 | and "warn" are permitted in that ACL, we don't need to test the verb. |
| 2843 | |
| 2844 | These modifiers act in different ways: |
| 2845 | |
| 2846 | "message" is a user message that will be included in an SMTP response. Unless |
| 2847 | it is empty, it overrides any previously set user message. |
| 2848 | |
| 2849 | "log_message" is a non-user message, and it adds to any existing non-user |
| 2850 | message that is already set. |
| 2851 | |
| 2852 | If there isn't a log message set, we make it the same as the user message. */ |
| 2853 | |
| 2854 | if (((rc == FAIL_DROP)? FAIL : rc) == msgcond[verb] || |
| 2855 | (verb == ACL_DISCARD && rc == OK) || |
| 2856 | (where == ACL_WHERE_QUIT)) |
| 2857 | { |
| 2858 | uschar *expmessage; |
| 2859 | |
| 2860 | /* If the verb is "warn", messages generated by conditions (verification or |
| 2861 | nested ACLs) are discarded. Only messages specified at this level are used. |
| 2862 | However, the value of an existing message is available in $acl_verify_message |
| 2863 | during expansions. */ |
| 2864 | |
| 2865 | uschar *old_user_msgptr = *user_msgptr; |
| 2866 | uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr; |
| 2867 | |
| 2868 | if (verb == ACL_WARN) *log_msgptr = *user_msgptr = NULL; |
| 2869 | |
| 2870 | if (user_message != NULL) |
| 2871 | { |
| 2872 | acl_verify_message = old_user_msgptr; |
| 2873 | expmessage = expand_string(user_message); |
| 2874 | if (expmessage == NULL) |
| 2875 | { |
| 2876 | if (!expand_string_forcedfail) |
| 2877 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s", |
| 2878 | user_message, expand_string_message); |
| 2879 | } |
| 2880 | else if (expmessage[0] != 0) *user_msgptr = expmessage; |
| 2881 | } |
| 2882 | |
| 2883 | if (log_message != NULL) |
| 2884 | { |
| 2885 | acl_verify_message = old_log_msgptr; |
| 2886 | expmessage = expand_string(log_message); |
| 2887 | if (expmessage == NULL) |
| 2888 | { |
| 2889 | if (!expand_string_forcedfail) |
| 2890 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s", |
| 2891 | log_message, expand_string_message); |
| 2892 | } |
| 2893 | else if (expmessage[0] != 0) |
| 2894 | { |
| 2895 | *log_msgptr = (*log_msgptr == NULL)? expmessage : |
| 2896 | string_sprintf("%s: %s", expmessage, *log_msgptr); |
| 2897 | } |
| 2898 | } |
| 2899 | |
| 2900 | /* If no log message, default it to the user message */ |
| 2901 | |
| 2902 | if (*log_msgptr == NULL) *log_msgptr = *user_msgptr; |
| 2903 | } |
| 2904 | |
| 2905 | acl_verify_message = NULL; |
| 2906 | return rc; |
| 2907 | } |
| 2908 | |
| 2909 | |
| 2910 | |
| 2911 | |
| 2912 | |
| 2913 | /************************************************* |
| 2914 | * Get line from a literal ACL * |
| 2915 | *************************************************/ |
| 2916 | |
| 2917 | /* This function is passed to acl_read() in order to extract individual lines |
| 2918 | of a literal ACL, which we access via static pointers. We can destroy the |
| 2919 | contents because this is called only once (the compiled ACL is remembered). |
| 2920 | |
| 2921 | This code is intended to treat the data in the same way as lines in the main |
| 2922 | Exim configuration file. That is: |
| 2923 | |
| 2924 | . Leading spaces are ignored. |
| 2925 | |
| 2926 | . A \ at the end of a line is a continuation - trailing spaces after the \ |
| 2927 | are permitted (this is because I don't believe in making invisible things |
| 2928 | significant). Leading spaces on the continued part of a line are ignored. |
| 2929 | |
| 2930 | . Physical lines starting (significantly) with # are totally ignored, and |
| 2931 | may appear within a sequence of backslash-continued lines. |
| 2932 | |
| 2933 | . Blank lines are ignored, but will end a sequence of continuations. |
| 2934 | |
| 2935 | Arguments: none |
| 2936 | Returns: a pointer to the next line |
| 2937 | */ |
| 2938 | |
| 2939 | |
| 2940 | static uschar *acl_text; /* Current pointer in the text */ |
| 2941 | static uschar *acl_text_end; /* Points one past the terminating '0' */ |
| 2942 | |
| 2943 | |
| 2944 | static uschar * |
| 2945 | acl_getline(void) |
| 2946 | { |
| 2947 | uschar *yield; |
| 2948 | |
| 2949 | /* This loop handles leading blank lines and comments. */ |
| 2950 | |
| 2951 | for(;;) |
| 2952 | { |
| 2953 | while (isspace(*acl_text)) acl_text++; /* Leading spaces/empty lines */ |
| 2954 | if (*acl_text == 0) return NULL; /* No more data */ |
| 2955 | yield = acl_text; /* Potential data line */ |
| 2956 | |
| 2957 | while (*acl_text != 0 && *acl_text != '\n') acl_text++; |
| 2958 | |
| 2959 | /* If we hit the end before a newline, we have the whole logical line. If |
| 2960 | it's a comment, there's no more data to be given. Otherwise, yield it. */ |
| 2961 | |
| 2962 | if (*acl_text == 0) return (*yield == '#')? NULL : yield; |
| 2963 | |
| 2964 | /* After reaching a newline, end this loop if the physical line does not |
| 2965 | start with '#'. If it does, it's a comment, and the loop continues. */ |
| 2966 | |
| 2967 | if (*yield != '#') break; |
| 2968 | } |
| 2969 | |
| 2970 | /* This loop handles continuations. We know we have some real data, ending in |
| 2971 | newline. See if there is a continuation marker at the end (ignoring trailing |
| 2972 | white space). We know that *yield is not white space, so no need to test for |
| 2973 | cont > yield in the backwards scanning loop. */ |
| 2974 | |
| 2975 | for(;;) |
| 2976 | { |
| 2977 | uschar *cont; |
| 2978 | for (cont = acl_text - 1; isspace(*cont); cont--); |
| 2979 | |
| 2980 | /* If no continuation follows, we are done. Mark the end of the line and |
| 2981 | return it. */ |
| 2982 | |
| 2983 | if (*cont != '\\') |
| 2984 | { |
| 2985 | *acl_text++ = 0; |
| 2986 | return yield; |
| 2987 | } |
| 2988 | |
| 2989 | /* We have encountered a continuation. Skip over whitespace at the start of |
| 2990 | the next line, and indeed the whole of the next line or lines if they are |
| 2991 | comment lines. */ |
| 2992 | |
| 2993 | for (;;) |
| 2994 | { |
| 2995 | while (*(++acl_text) == ' ' || *acl_text == '\t'); |
| 2996 | if (*acl_text != '#') break; |
| 2997 | while (*(++acl_text) != 0 && *acl_text != '\n'); |
| 2998 | } |
| 2999 | |
| 3000 | /* We have the start of a continuation line. Move all the rest of the data |
| 3001 | to join onto the previous line, and then find its end. If the end is not a |
| 3002 | newline, we are done. Otherwise loop to look for another continuation. */ |
| 3003 | |
| 3004 | memmove(cont, acl_text, acl_text_end - acl_text); |
| 3005 | acl_text_end -= acl_text - cont; |
| 3006 | acl_text = cont; |
| 3007 | while (*acl_text != 0 && *acl_text != '\n') acl_text++; |
| 3008 | if (*acl_text == 0) return yield; |
| 3009 | } |
| 3010 | |
| 3011 | /* Control does not reach here */ |
| 3012 | } |
| 3013 | |
| 3014 | |
| 3015 | |
| 3016 | |
| 3017 | |
| 3018 | /************************************************* |
| 3019 | * Check access using an ACL * |
| 3020 | *************************************************/ |
| 3021 | |
| 3022 | /* This function is called from address_check. It may recurse via |
| 3023 | acl_check_condition() - hence the use of a level to stop looping. The ACL is |
| 3024 | passed as a string which is expanded. A forced failure implies no access check |
| 3025 | is required. If the result is a single word, it is taken as the name of an ACL |
| 3026 | which is sought in the global ACL tree. Otherwise, it is taken as literal ACL |
| 3027 | text, complete with newlines, and parsed as such. In both cases, the ACL check |
| 3028 | is then run. This function uses an auxiliary function for acl_read() to call |
| 3029 | for reading individual lines of a literal ACL. This is acl_getline(), which |
| 3030 | appears immediately above. |
| 3031 | |
| 3032 | Arguments: |
| 3033 | where where called from |
| 3034 | addr address item when called from RCPT; otherwise NULL |
| 3035 | s the input string; NULL is the same as an empty ACL => DENY |
| 3036 | level the nesting level |
| 3037 | user_msgptr where to put a user error (for SMTP response) |
| 3038 | log_msgptr where to put a logging message (not for SMTP response) |
| 3039 | |
| 3040 | Returns: OK access is granted |
| 3041 | DISCARD access is apparently granted... |
| 3042 | FAIL access is denied |
| 3043 | FAIL_DROP access is denied; drop the connection |
| 3044 | DEFER can't tell at the moment |
| 3045 | ERROR disaster |
| 3046 | */ |
| 3047 | |
| 3048 | static int |
| 3049 | acl_check_internal(int where, address_item *addr, uschar *s, int level, |
| 3050 | uschar **user_msgptr, uschar **log_msgptr) |
| 3051 | { |
| 3052 | int fd = -1; |
| 3053 | acl_block *acl = NULL; |
| 3054 | uschar *acl_name = US"inline ACL"; |
| 3055 | uschar *ss; |
| 3056 | |
| 3057 | /* Catch configuration loops */ |
| 3058 | |
| 3059 | if (level > 20) |
| 3060 | { |
| 3061 | *log_msgptr = US"ACL nested too deep: possible loop"; |
| 3062 | return ERROR; |
| 3063 | } |
| 3064 | |
| 3065 | if (s == NULL) |
| 3066 | { |
| 3067 | HDEBUG(D_acl) debug_printf("ACL is NULL: implicit DENY\n"); |
| 3068 | return FAIL; |
| 3069 | } |
| 3070 | |
| 3071 | /* At top level, we expand the incoming string. At lower levels, it has already |
| 3072 | been expanded as part of condition processing. */ |
| 3073 | |
| 3074 | if (level == 0) |
| 3075 | { |
| 3076 | ss = expand_string(s); |
| 3077 | if (ss == NULL) |
| 3078 | { |
| 3079 | if (expand_string_forcedfail) return OK; |
| 3080 | *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s, |
| 3081 | expand_string_message); |
| 3082 | return ERROR; |
| 3083 | } |
| 3084 | } |
| 3085 | else ss = s; |
| 3086 | |
| 3087 | while (isspace(*ss))ss++; |
| 3088 | |
| 3089 | /* If we can't find a named ACL, the default is to parse it as an inline one. |
| 3090 | (Unless it begins with a slash; non-existent files give rise to an error.) */ |
| 3091 | |
| 3092 | acl_text = ss; |
| 3093 | |
| 3094 | /* Handle the case of a string that does not contain any spaces. Look for a |
| 3095 | named ACL among those read from the configuration, or a previously read file. |
| 3096 | It is possible that the pointer to the ACL is NULL if the configuration |
| 3097 | contains a name with no data. If not found, and the text begins with '/', |
| 3098 | read an ACL from a file, and save it so it can be re-used. */ |
| 3099 | |
| 3100 | if (Ustrchr(ss, ' ') == NULL) |
| 3101 | { |
| 3102 | tree_node *t = tree_search(acl_anchor, ss); |
| 3103 | if (t != NULL) |
| 3104 | { |
| 3105 | acl = (acl_block *)(t->data.ptr); |
| 3106 | if (acl == NULL) |
| 3107 | { |
| 3108 | HDEBUG(D_acl) debug_printf("ACL \"%s\" is empty: implicit DENY\n", ss); |
| 3109 | return FAIL; |
| 3110 | } |
| 3111 | acl_name = string_sprintf("ACL \"%s\"", ss); |
| 3112 | HDEBUG(D_acl) debug_printf("using ACL \"%s\"\n", ss); |
| 3113 | } |
| 3114 | |
| 3115 | else if (*ss == '/') |
| 3116 | { |
| 3117 | struct stat statbuf; |
| 3118 | fd = Uopen(ss, O_RDONLY, 0); |
| 3119 | if (fd < 0) |
| 3120 | { |
| 3121 | *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss, |
| 3122 | strerror(errno)); |
| 3123 | return ERROR; |
| 3124 | } |
| 3125 | |
| 3126 | if (fstat(fd, &statbuf) != 0) |
| 3127 | { |
| 3128 | *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss, |
| 3129 | strerror(errno)); |
| 3130 | return ERROR; |
| 3131 | } |
| 3132 | |
| 3133 | acl_text = store_get(statbuf.st_size + 1); |
| 3134 | acl_text_end = acl_text + statbuf.st_size + 1; |
| 3135 | |
| 3136 | if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size) |
| 3137 | { |
| 3138 | *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s", |
| 3139 | ss, strerror(errno)); |
| 3140 | return ERROR; |
| 3141 | } |
| 3142 | acl_text[statbuf.st_size] = 0; |
| 3143 | (void)close(fd); |
| 3144 | |
| 3145 | acl_name = string_sprintf("ACL \"%s\"", ss); |
| 3146 | HDEBUG(D_acl) debug_printf("read ACL from file %s\n", ss); |
| 3147 | } |
| 3148 | } |
| 3149 | |
| 3150 | /* Parse an ACL that is still in text form. If it came from a file, remember it |
| 3151 | in the ACL tree, having read it into the POOL_PERM store pool so that it |
| 3152 | persists between multiple messages. */ |
| 3153 | |
| 3154 | if (acl == NULL) |
| 3155 | { |
| 3156 | int old_pool = store_pool; |
| 3157 | if (fd >= 0) store_pool = POOL_PERM; |
| 3158 | acl = acl_read(acl_getline, log_msgptr); |
| 3159 | store_pool = old_pool; |
| 3160 | if (acl == NULL && *log_msgptr != NULL) return ERROR; |
| 3161 | if (fd >= 0) |
| 3162 | { |
| 3163 | tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss)); |
| 3164 | Ustrcpy(t->name, ss); |
| 3165 | t->data.ptr = acl; |
| 3166 | (void)tree_insertnode(&acl_anchor, t); |
| 3167 | } |
| 3168 | } |
| 3169 | |
| 3170 | /* Now we have an ACL to use. It's possible it may be NULL. */ |
| 3171 | |
| 3172 | while (acl != NULL) |
| 3173 | { |
| 3174 | int cond; |
| 3175 | int basic_errno = 0; |
| 3176 | BOOL endpass_seen = FALSE; |
| 3177 | |
| 3178 | *log_msgptr = *user_msgptr = NULL; |
| 3179 | acl_temp_details = FALSE; |
| 3180 | |
| 3181 | if (where == ACL_WHERE_QUIT && |
| 3182 | acl->verb != ACL_ACCEPT && |
| 3183 | acl->verb != ACL_WARN) |
| 3184 | { |
| 3185 | *log_msgptr = string_sprintf("\"%s\" is not allowed in a QUIT ACL", |
| 3186 | verbs[acl->verb]); |
| 3187 | return ERROR; |
| 3188 | } |
| 3189 | |
| 3190 | HDEBUG(D_acl) debug_printf("processing \"%s\"\n", verbs[acl->verb]); |
| 3191 | |
| 3192 | /* Clear out any search error message from a previous check before testing |
| 3193 | this condition. */ |
| 3194 | |
| 3195 | search_error_message = NULL; |
| 3196 | cond = acl_check_condition(acl->verb, acl->condition, where, addr, level, |
| 3197 | &endpass_seen, user_msgptr, log_msgptr, &basic_errno); |
| 3198 | |
| 3199 | /* Handle special returns: DEFER causes a return except on a WARN verb; |
| 3200 | ERROR always causes a return. */ |
| 3201 | |
| 3202 | switch (cond) |
| 3203 | { |
| 3204 | case DEFER: |
| 3205 | HDEBUG(D_acl) debug_printf("%s: condition test deferred\n", verbs[acl->verb]); |
| 3206 | if (basic_errno != ERRNO_CALLOUTDEFER) |
| 3207 | { |
| 3208 | if (search_error_message != NULL && *search_error_message != 0) |
| 3209 | *log_msgptr = search_error_message; |
| 3210 | if (smtp_return_error_details) acl_temp_details = TRUE; |
| 3211 | } |
| 3212 | else |
| 3213 | { |
| 3214 | acl_temp_details = TRUE; |
| 3215 | } |
| 3216 | if (acl->verb != ACL_WARN) return DEFER; |
| 3217 | break; |
| 3218 | |
| 3219 | default: /* Paranoia */ |
| 3220 | case ERROR: |
| 3221 | HDEBUG(D_acl) debug_printf("%s: condition test error\n", verbs[acl->verb]); |
| 3222 | return ERROR; |
| 3223 | |
| 3224 | case OK: |
| 3225 | HDEBUG(D_acl) debug_printf("%s: condition test succeeded\n", |
| 3226 | verbs[acl->verb]); |
| 3227 | break; |
| 3228 | |
| 3229 | case FAIL: |
| 3230 | HDEBUG(D_acl) debug_printf("%s: condition test failed\n", verbs[acl->verb]); |
| 3231 | break; |
| 3232 | |
| 3233 | /* DISCARD and DROP can happen only from a nested ACL condition, and |
| 3234 | DISCARD can happen only for an "accept" or "discard" verb. */ |
| 3235 | |
| 3236 | case DISCARD: |
| 3237 | HDEBUG(D_acl) debug_printf("%s: condition test yielded \"discard\"\n", |
| 3238 | verbs[acl->verb]); |
| 3239 | break; |
| 3240 | |
| 3241 | case FAIL_DROP: |
| 3242 | HDEBUG(D_acl) debug_printf("%s: condition test yielded \"drop\"\n", |
| 3243 | verbs[acl->verb]); |
| 3244 | break; |
| 3245 | } |
| 3246 | |
| 3247 | /* At this point, cond for most verbs is either OK or FAIL or (as a result of |
| 3248 | a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and |
| 3249 | for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */ |
| 3250 | |
| 3251 | switch(acl->verb) |
| 3252 | { |
| 3253 | case ACL_ACCEPT: |
| 3254 | if (cond == OK || cond == DISCARD) return cond; |
| 3255 | if (endpass_seen) |
| 3256 | { |
| 3257 | HDEBUG(D_acl) debug_printf("accept: endpass encountered - denying access\n"); |
| 3258 | return cond; |
| 3259 | } |
| 3260 | break; |
| 3261 | |
| 3262 | case ACL_DEFER: |
| 3263 | if (cond == OK) |
| 3264 | { |
| 3265 | acl_temp_details = TRUE; |
| 3266 | return DEFER; |
| 3267 | } |
| 3268 | break; |
| 3269 | |
| 3270 | case ACL_DENY: |
| 3271 | if (cond == OK) return FAIL; |
| 3272 | break; |
| 3273 | |
| 3274 | case ACL_DISCARD: |
| 3275 | if (cond == OK || cond == DISCARD) return DISCARD; |
| 3276 | if (endpass_seen) |
| 3277 | { |
| 3278 | HDEBUG(D_acl) debug_printf("discard: endpass encountered - denying access\n"); |
| 3279 | return cond; |
| 3280 | } |
| 3281 | break; |
| 3282 | |
| 3283 | case ACL_DROP: |
| 3284 | if (cond == OK) return FAIL_DROP; |
| 3285 | break; |
| 3286 | |
| 3287 | case ACL_REQUIRE: |
| 3288 | if (cond != OK) return cond; |
| 3289 | break; |
| 3290 | |
| 3291 | case ACL_WARN: |
| 3292 | if (cond == OK) |
| 3293 | acl_warn(where, *user_msgptr, *log_msgptr); |
| 3294 | else if (cond == DEFER) |
| 3295 | log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: " |
| 3296 | "condition test deferred%s%s", host_and_ident(TRUE), |
| 3297 | (*log_msgptr == NULL)? US"" : US": ", |
| 3298 | (*log_msgptr == NULL)? US"" : *log_msgptr); |
| 3299 | *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */ |
| 3300 | break; |
| 3301 | |
| 3302 | default: |
| 3303 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d", |
| 3304 | acl->verb); |
| 3305 | break; |
| 3306 | } |
| 3307 | |
| 3308 | /* Pass to the next ACL item */ |
| 3309 | |
| 3310 | acl = acl->next; |
| 3311 | } |
| 3312 | |
| 3313 | /* We have reached the end of the ACL. This is an implicit DENY. */ |
| 3314 | |
| 3315 | HDEBUG(D_acl) debug_printf("end of %s: implicit DENY\n", acl_name); |
| 3316 | return FAIL; |
| 3317 | } |
| 3318 | |
| 3319 | |
| 3320 | /************************************************* |
| 3321 | * Check access using an ACL * |
| 3322 | *************************************************/ |
| 3323 | |
| 3324 | /* This is the external interface for ACL checks. It sets up an address and the |
| 3325 | expansions for $domain and $local_part when called after RCPT, then calls |
| 3326 | acl_check_internal() to do the actual work. |
| 3327 | |
| 3328 | Arguments: |
| 3329 | where ACL_WHERE_xxxx indicating where called from |
| 3330 | data_string RCPT address, or SMTP command argument, or NULL |
| 3331 | s the input string; NULL is the same as an empty ACL => DENY |
| 3332 | user_msgptr where to put a user error (for SMTP response) |
| 3333 | log_msgptr where to put a logging message (not for SMTP response) |
| 3334 | |
| 3335 | Returns: OK access is granted by an ACCEPT verb |
| 3336 | DISCARD access is granted by a DISCARD verb |
| 3337 | FAIL access is denied |
| 3338 | FAIL_DROP access is denied; drop the connection |
| 3339 | DEFER can't tell at the moment |
| 3340 | ERROR disaster |
| 3341 | */ |
| 3342 | |
| 3343 | int |
| 3344 | acl_check(int where, uschar *data_string, uschar *s, uschar **user_msgptr, |
| 3345 | uschar **log_msgptr) |
| 3346 | { |
| 3347 | int rc; |
| 3348 | address_item adb; |
| 3349 | address_item *addr; |
| 3350 | |
| 3351 | *user_msgptr = *log_msgptr = NULL; |
| 3352 | sender_verified_failed = NULL; |
| 3353 | ratelimiters_cmd = NULL; |
| 3354 | |
| 3355 | if (where == ACL_WHERE_RCPT) |
| 3356 | { |
| 3357 | adb = address_defaults; |
| 3358 | addr = &adb; |
| 3359 | addr->address = data_string; |
| 3360 | if (deliver_split_address(addr) == DEFER) |
| 3361 | { |
| 3362 | *log_msgptr = US"defer in percent_hack_domains check"; |
| 3363 | return DEFER; |
| 3364 | } |
| 3365 | deliver_domain = addr->domain; |
| 3366 | deliver_localpart = addr->local_part; |
| 3367 | } |
| 3368 | else |
| 3369 | { |
| 3370 | addr = NULL; |
| 3371 | smtp_command_argument = data_string; |
| 3372 | } |
| 3373 | |
| 3374 | rc = acl_check_internal(where, addr, s, 0, user_msgptr, log_msgptr); |
| 3375 | |
| 3376 | smtp_command_argument = deliver_domain = |
| 3377 | deliver_localpart = deliver_address_data = sender_address_data = NULL; |
| 3378 | |
| 3379 | /* A DISCARD response is permitted only for message ACLs, excluding the PREDATA |
| 3380 | ACL, which is really in the middle of an SMTP command. */ |
| 3381 | |
| 3382 | if (rc == DISCARD) |
| 3383 | { |
| 3384 | if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA) |
| 3385 | { |
| 3386 | log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s " |
| 3387 | "ACL", acl_wherenames[where]); |
| 3388 | return ERROR; |
| 3389 | } |
| 3390 | return DISCARD; |
| 3391 | } |
| 3392 | |
| 3393 | /* A DROP response is not permitted from MAILAUTH */ |
| 3394 | |
| 3395 | if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH) |
| 3396 | { |
| 3397 | log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s " |
| 3398 | "ACL", acl_wherenames[where]); |
| 3399 | return ERROR; |
| 3400 | } |
| 3401 | |
| 3402 | /* Before giving an error response, take a look at the length of any user |
| 3403 | message, and split it up into multiple lines if possible. */ |
| 3404 | |
| 3405 | if (rc != OK && *user_msgptr != NULL && Ustrlen(*user_msgptr) > 75) |
| 3406 | { |
| 3407 | uschar *s = *user_msgptr = string_copy(*user_msgptr); |
| 3408 | uschar *ss = s; |
| 3409 | |
| 3410 | for (;;) |
| 3411 | { |
| 3412 | int i = 0; |
| 3413 | while (i < 75 && *ss != 0 && *ss != '\n') ss++, i++; |
| 3414 | if (*ss == 0) break; |
| 3415 | if (*ss == '\n') |
| 3416 | s = ++ss; |
| 3417 | else |
| 3418 | { |
| 3419 | uschar *t = ss + 1; |
| 3420 | uschar *tt = NULL; |
| 3421 | while (--t > s + 35) |
| 3422 | { |
| 3423 | if (*t == ' ') |
| 3424 | { |
| 3425 | if (t[-1] == ':') { tt = t; break; } |
| 3426 | if (tt == NULL) tt = t; |
| 3427 | } |
| 3428 | } |
| 3429 | |
| 3430 | if (tt == NULL) /* Can't split behind - try ahead */ |
| 3431 | { |
| 3432 | t = ss + 1; |
| 3433 | while (*t != 0) |
| 3434 | { |
| 3435 | if (*t == ' ' || *t == '\n') |
| 3436 | { tt = t; break; } |
| 3437 | t++; |
| 3438 | } |
| 3439 | } |
| 3440 | |
| 3441 | if (tt == NULL) break; /* Can't find anywhere to split */ |
| 3442 | *tt = '\n'; |
| 3443 | s = ss = tt+1; |
| 3444 | } |
| 3445 | } |
| 3446 | } |
| 3447 | |
| 3448 | return rc; |
| 3449 | } |
| 3450 | |
| 3451 | /* End of acl.c */ |