1 /* 2 * Copyright (c) 2008-2014, Simon Schubert <2@0x2c.org>. 3 * Copyright (c) 2008 The DragonFly Project. All rights reserved. 4 * 5 * This code is derived from software contributed to The DragonFly Project 6 * by Simon Schubert <2@0x2c.org>. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * 3. Neither the name of The DragonFly Project nor the names of its 19 * contributors may be used to endorse or promote products derived 20 * from this software without specific, prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <errno.h> 37 #include <inttypes.h> 38 #include <signal.h> 39 #include <syslog.h> 40 #include <unistd.h> 41 #include <ctype.h> 42 43 #include "dma.h" 44 45 void 46 bounce(struct qitem *it, const char *reason) 47 { 48 struct queue bounceq; 49 char line[1000]; 50 size_t pos; 51 int error; 52 53 /* Don't bounce bounced mails */ 54 if (it->sender[0] == 0) { 55 syslog(LOG_INFO, "can not bounce a bounce message, discarding"); 56 exit(EX_SOFTWARE); 57 } 58 59 bzero(&bounceq, sizeof(bounceq)); 60 LIST_INIT(&bounceq.queue); 61 bounceq.sender = ""; 62 if (add_recp(&bounceq, it->sender, EXPAND_WILDCARD) != 0) 63 goto fail; 64 65 if (newspoolf(&bounceq) != 0) 66 goto fail; 67 68 syslog(LOG_ERR, "delivery failed, bouncing as %s", bounceq.id); 69 setlogident("%s", bounceq.id); 70 71 error = fprintf(bounceq.mailf, 72 "Received: from MAILER-DAEMON\n" 73 "\tid %s\n" 74 "\tby %s (%s);\n" 75 "\t%s\n" 76 "X-Original-To: <%s>\n" 77 "From: MAILER-DAEMON <>\n" 78 "To: %s\n" 79 "Subject: Mail delivery failed\n" 80 "Message-Id: <%s@%s>\n" 81 "Date: %s\n" 82 "\n" 83 "This is the %s at %s.\n" 84 "\n" 85 "There was an error delivering your mail to <%s>.\n" 86 "\n" 87 "%s\n" 88 "\n" 89 "%s\n" 90 "\n", 91 bounceq.id, 92 hostname(), VERSION, 93 rfc822date(), 94 it->addr, 95 it->sender, 96 bounceq.id, hostname(), 97 rfc822date(), 98 VERSION, hostname(), 99 it->addr, 100 reason, 101 config.features & FULLBOUNCE ? 102 "Original message follows." : 103 "Message headers follow."); 104 if (error < 0) 105 goto fail; 106 107 if (fseek(it->mailf, 0, SEEK_SET) != 0) 108 goto fail; 109 if (config.features & FULLBOUNCE) { 110 while ((pos = fread(line, 1, sizeof(line), it->mailf)) > 0) { 111 if (fwrite(line, 1, pos, bounceq.mailf) != pos) 112 goto fail; 113 } 114 } else { 115 while (!feof(it->mailf)) { 116 if (fgets(line, sizeof(line), it->mailf) == NULL) 117 break; 118 if (line[0] == '\n') 119 break; 120 if (fwrite(line, strlen(line), 1, bounceq.mailf) != 1) 121 goto fail; 122 } 123 } 124 125 if (linkspool(&bounceq) != 0) 126 goto fail; 127 /* bounce is safe */ 128 129 delqueue(it); 130 131 run_queue(&bounceq); 132 /* NOTREACHED */ 133 134 fail: 135 syslog(LOG_CRIT, "error creating bounce: %m"); 136 delqueue(it); 137 exit(EX_IOERR); 138 } 139 140 struct parse_state { 141 char addr[1000]; 142 int pos; 143 144 enum { 145 NONE = 0, 146 START, 147 MAIN, 148 EOL, 149 QUIT 150 } state; 151 int comment; 152 int quote; 153 int brackets; 154 int esc; 155 }; 156 157 /* 158 * Simplified RFC2822 header/address parsing. 159 * We copy escapes and quoted strings directly, since 160 * we have to pass them like this to the mail server anyways. 161 * XXX local addresses will need treatment 162 */ 163 static int 164 parse_addrs(struct parse_state *ps, char *s, struct queue *queue) 165 { 166 char *addr; 167 168 again: 169 switch (ps->state) { 170 case NONE: 171 return (-1); 172 173 case START: 174 /* init our data */ 175 bzero(ps, sizeof(*ps)); 176 177 /* skip over header name */ 178 while (*s != ':') 179 s++; 180 s++; 181 ps->state = MAIN; 182 break; 183 184 case MAIN: 185 /* all fine */ 186 break; 187 188 case EOL: 189 switch (*s) { 190 case ' ': 191 case '\t': 192 s++; 193 /* continue */ 194 break; 195 196 default: 197 ps->state = QUIT; 198 if (ps->pos != 0) 199 goto newaddr; 200 return (0); 201 } 202 203 case QUIT: 204 return (0); 205 } 206 207 for (; *s != 0; s++) { 208 if (ps->esc) { 209 ps->esc = 0; 210 211 switch (*s) { 212 case '\r': 213 case '\n': 214 goto err; 215 216 default: 217 goto copy; 218 } 219 } 220 221 if (ps->quote) { 222 switch (*s) { 223 case '"': 224 ps->quote = 0; 225 goto copy; 226 227 case '\\': 228 ps->esc = 1; 229 goto copy; 230 231 case '\r': 232 case '\n': 233 goto eol; 234 235 default: 236 goto copy; 237 } 238 } 239 240 switch (*s) { 241 case '(': 242 ps->comment++; 243 break; 244 245 case ')': 246 if (ps->comment) 247 ps->comment--; 248 else 249 goto err; 250 goto skip; 251 252 case '"': 253 ps->quote = 1; 254 goto copy; 255 256 case '\\': 257 ps->esc = 1; 258 goto copy; 259 260 case '\r': 261 case '\n': 262 goto eol; 263 } 264 265 if (ps->comment) 266 goto skip; 267 268 switch (*s) { 269 case ' ': 270 case '\t': 271 /* ignore whitespace */ 272 goto skip; 273 274 case '<': 275 /* this is the real address now */ 276 ps->brackets = 1; 277 ps->pos = 0; 278 goto skip; 279 280 case '>': 281 if (!ps->brackets) 282 goto err; 283 ps->brackets = 0; 284 285 s++; 286 goto newaddr; 287 288 case ':': 289 /* group - ignore */ 290 ps->pos = 0; 291 goto skip; 292 293 case ',': 294 case ';': 295 /* 296 * Next address, copy previous one. 297 * However, we might be directly after 298 * a <address>, or have two consecutive 299 * commas. 300 * Skip the comma unless there is 301 * really something to copy. 302 */ 303 if (ps->pos == 0) 304 goto skip; 305 s++; 306 goto newaddr; 307 308 default: 309 goto copy; 310 } 311 312 copy: 313 if (ps->comment) 314 goto skip; 315 316 if (ps->pos + 1 == sizeof(ps->addr)) 317 goto err; 318 ps->addr[ps->pos++] = *s; 319 320 skip: 321 ; 322 } 323 324 eol: 325 ps->state = EOL; 326 return (0); 327 328 err: 329 ps->state = QUIT; 330 return (-1); 331 332 newaddr: 333 ps->addr[ps->pos] = 0; 334 ps->pos = 0; 335 addr = strdup(ps->addr); 336 if (addr == NULL) 337 errlog(EX_SOFTWARE, "strdup"); 338 339 if (add_recp(queue, addr, EXPAND_WILDCARD) != 0) 340 errlogx(EX_DATAERR, "invalid recipient `%s'", addr); 341 342 goto again; 343 } 344 345 static int 346 writeline(struct queue *queue, const char *line, ssize_t linelen) 347 { 348 ssize_t len; 349 350 while (linelen > 0) { 351 len = linelen; 352 if (linelen > 1000) { 353 len = 990; 354 } 355 if (fwrite(line, len, 1, queue->mailf) != 1) 356 return (-1); 357 if (linelen <= 1000) 358 break; 359 if (fwrite("\n", 1, 1, queue->mailf) != 1) 360 return (-1); 361 line += 990; 362 linelen = strlen(line); 363 } 364 return (0); 365 } 366 367 int 368 readmail(struct queue *queue, int nodot, int recp_from_header) 369 { 370 struct parse_state parse_state; 371 char *line = NULL; 372 ssize_t linelen; 373 size_t linecap = 0; 374 char newline[1000]; 375 size_t error; 376 int had_headers = 0; 377 int had_from = 0; 378 int had_messagid = 0; 379 int had_date = 0; 380 int nocopy = 0; 381 382 parse_state.state = NONE; 383 384 error = fprintf(queue->mailf, 385 "Received: from %s (uid %d)\n" 386 "\t(envelope-from %s)\n" 387 "\tid %s\n" 388 "\tby %s (%s);\n" 389 "\t%s\n", 390 username, useruid, 391 queue->sender, 392 queue->id, 393 hostname(), VERSION, 394 rfc822date()); 395 if ((ssize_t)error < 0) 396 return (-1); 397 398 while (!feof(stdin)) { 399 newline[0] = '\0'; 400 if ((linelen = getline(&line, &linecap, stdin)) <= 0) 401 break; 402 if (!had_headers) { 403 if (linelen > 1000) 404 errlogx(EX_DATAERR, "bad mail input format:" 405 " from %s (uid %d) (envelope-from %s)", 406 username, useruid, queue->sender); 407 408 /* 409 * Unless this is a continuation, switch of 410 * the Bcc: nocopy flag. 411 */ 412 if (!(line[0] == ' ' || line[0] == '\t')) 413 nocopy = 0; 414 415 if (strprefixcmp(line, "Date:") == 0) 416 had_date = 1; 417 else if (strprefixcmp(line, "Message-Id:") == 0) 418 had_messagid = 1; 419 else if (strprefixcmp(line, "From:") == 0) 420 had_from = 1; 421 else if (strprefixcmp(line, "Bcc:") == 0) 422 nocopy = 1; 423 424 if (parse_state.state != NONE) { 425 if (parse_addrs(&parse_state, line, queue) < 0) { 426 errlogx(EX_DATAERR, "invalid address in header\n"); 427 /* NOTREACHED */ 428 } 429 } 430 431 if (recp_from_header && ( 432 strprefixcmp(line, "To:") == 0 || 433 strprefixcmp(line, "Cc:") == 0 || 434 strprefixcmp(line, "Bcc:") == 0)) { 435 parse_state.state = START; 436 if (parse_addrs(&parse_state, line, queue) < 0) { 437 errlogx(EX_DATAERR, "invalid address in header\n"); 438 /* NOTREACHED */ 439 } 440 } 441 } 442 443 if (line[0] == '\n' && !had_headers) { 444 had_headers = 1; 445 while (!had_date || !had_messagid || !had_from) { 446 if (!had_date) { 447 had_date = 1; 448 snprintf(newline, sizeof(newline), "Date: %s\n", rfc822date()); 449 } else if (!had_messagid) { 450 /* XXX msgid, assign earlier and log? */ 451 had_messagid = 1; 452 snprintf(newline, sizeof(newline), "Message-Id: <%"PRIxMAX".%s.%"PRIxMAX"@%s>\n", 453 (uintmax_t)time(NULL), 454 queue->id, 455 (uintmax_t)random(), 456 hostname()); 457 } else if (!had_from) { 458 had_from = 1; 459 snprintf(newline, sizeof(newline), "From: <%s>\n", queue->sender); 460 } 461 if (fwrite(newline, strlen(newline), 1, queue->mailf) != 1) 462 goto fail; 463 } 464 strlcpy(newline, "\n", sizeof(newline)); 465 } 466 if (!nodot && linelen == 2 && line[0] == '.') 467 break; 468 if (!nocopy) { 469 if (newline[0] != '\0') { 470 if (fwrite(newline, strlen(newline), 1, queue->mailf) != 1) 471 goto fail; 472 } else { 473 if (writeline(queue, line, linelen) != 0) 474 goto fail; 475 } 476 } 477 } 478 479 return (0); 480 fail: 481 free(line); 482 return (-1); 483 } 484