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 42 #include "dma.h" 43 44 void 45 bounce(struct qitem *it, const char *reason) 46 { 47 struct queue bounceq; 48 char line[1000]; 49 size_t pos; 50 int error; 51 52 /* Don't bounce bounced mails */ 53 if (it->sender[0] == 0) { 54 syslog(LOG_INFO, "can not bounce a bounce message, discarding"); 55 exit(EX_SOFTWARE); 56 } 57 58 bzero(&bounceq, sizeof(bounceq)); 59 LIST_INIT(&bounceq.queue); 60 bounceq.sender = ""; 61 if (add_recp(&bounceq, it->sender, EXPAND_WILDCARD) != 0) 62 goto fail; 63 64 if (newspoolf(&bounceq) != 0) 65 goto fail; 66 67 syslog(LOG_ERR, "delivery failed, bouncing as %s", bounceq.id); 68 setlogident("%s", bounceq.id); 69 70 error = fprintf(bounceq.mailf, 71 "Received: from MAILER-DAEMON\n" 72 "\tid %s\n" 73 "\tby %s (%s);\n" 74 "\t%s\n" 75 "X-Original-To: <%s>\n" 76 "From: MAILER-DAEMON <>\n" 77 "To: %s\n" 78 "Subject: Mail delivery failed\n" 79 "Message-Id: <%s@%s>\n" 80 "Date: %s\n" 81 "\n" 82 "This is the %s at %s.\n" 83 "\n" 84 "There was an error delivering your mail to <%s>.\n" 85 "\n" 86 "%s\n" 87 "\n" 88 "%s\n" 89 "\n", 90 bounceq.id, 91 hostname(), VERSION, 92 rfc822date(), 93 it->addr, 94 it->sender, 95 bounceq.id, hostname(), 96 rfc822date(), 97 VERSION, hostname(), 98 it->addr, 99 reason, 100 config.features & FULLBOUNCE ? 101 "Original message follows." : 102 "Message headers follow."); 103 if (error < 0) 104 goto fail; 105 106 if (fseek(it->mailf, 0, SEEK_SET) != 0) 107 goto fail; 108 if (config.features & FULLBOUNCE) { 109 while ((pos = fread(line, 1, sizeof(line), it->mailf)) > 0) { 110 if (fwrite(line, 1, pos, bounceq.mailf) != pos) 111 goto fail; 112 } 113 } else { 114 while (!feof(it->mailf)) { 115 if (fgets(line, sizeof(line), it->mailf) == NULL) 116 break; 117 if (line[0] == '\n') 118 break; 119 if (fwrite(line, strlen(line), 1, bounceq.mailf) != 1) 120 goto fail; 121 } 122 } 123 124 if (linkspool(&bounceq) != 0) 125 goto fail; 126 /* bounce is safe */ 127 128 delqueue(it); 129 130 run_queue(&bounceq); 131 /* NOTREACHED */ 132 133 fail: 134 syslog(LOG_CRIT, "error creating bounce: %m"); 135 delqueue(it); 136 exit(EX_IOERR); 137 } 138 139 struct parse_state { 140 char addr[1000]; 141 int pos; 142 143 enum { 144 NONE = 0, 145 START, 146 MAIN, 147 EOL, 148 QUIT 149 } state; 150 int comment; 151 int quote; 152 int brackets; 153 int esc; 154 }; 155 156 /* 157 * Simplified RFC2822 header/address parsing. 158 * We copy escapes and quoted strings directly, since 159 * we have to pass them like this to the mail server anyways. 160 * XXX local addresses will need treatment 161 */ 162 static int 163 parse_addrs(struct parse_state *ps, char *s, struct queue *queue) 164 { 165 char *addr; 166 167 again: 168 switch (ps->state) { 169 case NONE: 170 return (-1); 171 172 case START: 173 /* init our data */ 174 bzero(ps, sizeof(*ps)); 175 176 /* skip over header name */ 177 while (*s != ':') 178 s++; 179 s++; 180 ps->state = MAIN; 181 break; 182 183 case MAIN: 184 /* all fine */ 185 break; 186 187 case EOL: 188 switch (*s) { 189 case ' ': 190 case '\t': 191 s++; 192 /* continue */ 193 break; 194 195 default: 196 ps->state = QUIT; 197 if (ps->pos != 0) 198 goto newaddr; 199 return (0); 200 } 201 202 case QUIT: 203 return (0); 204 } 205 206 for (; *s != 0; s++) { 207 if (ps->esc) { 208 ps->esc = 0; 209 210 switch (*s) { 211 case '\r': 212 case '\n': 213 goto err; 214 215 default: 216 goto copy; 217 } 218 } 219 220 if (ps->quote) { 221 switch (*s) { 222 case '"': 223 ps->quote = 0; 224 goto copy; 225 226 case '\\': 227 ps->esc = 1; 228 goto copy; 229 230 case '\r': 231 case '\n': 232 goto eol; 233 234 default: 235 goto copy; 236 } 237 } 238 239 switch (*s) { 240 case '(': 241 ps->comment++; 242 break; 243 244 case ')': 245 if (ps->comment) 246 ps->comment--; 247 else 248 goto err; 249 goto skip; 250 251 case '"': 252 ps->quote = 1; 253 goto copy; 254 255 case '\\': 256 ps->esc = 1; 257 goto copy; 258 259 case '\r': 260 case '\n': 261 goto eol; 262 } 263 264 if (ps->comment) 265 goto skip; 266 267 switch (*s) { 268 case ' ': 269 case '\t': 270 /* ignore whitespace */ 271 goto skip; 272 273 case '<': 274 /* this is the real address now */ 275 ps->brackets = 1; 276 ps->pos = 0; 277 goto skip; 278 279 case '>': 280 if (!ps->brackets) 281 goto err; 282 ps->brackets = 0; 283 284 s++; 285 goto newaddr; 286 287 case ':': 288 /* group - ignore */ 289 ps->pos = 0; 290 goto skip; 291 292 case ',': 293 case ';': 294 /* 295 * Next address, copy previous one. 296 * However, we might be directly after 297 * a <address>, or have two consecutive 298 * commas. 299 * Skip the comma unless there is 300 * really something to copy. 301 */ 302 if (ps->pos == 0) 303 goto skip; 304 s++; 305 goto newaddr; 306 307 default: 308 goto copy; 309 } 310 311 copy: 312 if (ps->comment) 313 goto skip; 314 315 if (ps->pos + 1 == sizeof(ps->addr)) 316 goto err; 317 ps->addr[ps->pos++] = *s; 318 319 skip: 320 ; 321 } 322 323 eol: 324 ps->state = EOL; 325 return (0); 326 327 err: 328 ps->state = QUIT; 329 return (-1); 330 331 newaddr: 332 ps->addr[ps->pos] = 0; 333 ps->pos = 0; 334 addr = strdup(ps->addr); 335 if (addr == NULL) 336 errlog(EX_SOFTWARE, "strdup"); 337 338 if (add_recp(queue, addr, EXPAND_WILDCARD) != 0) 339 errlogx(EX_DATAERR, "invalid recipient `%s'", addr); 340 341 goto again; 342 } 343 344 int 345 readmail(struct queue *queue, int nodot, int recp_from_header) 346 { 347 struct parse_state parse_state; 348 char line[1000]; /* by RFC2822 */ 349 size_t linelen; 350 size_t error; 351 int had_headers = 0; 352 int had_from = 0; 353 int had_messagid = 0; 354 int had_date = 0; 355 int had_last_line = 0; 356 int nocopy = 0; 357 358 parse_state.state = NONE; 359 360 error = fprintf(queue->mailf, 361 "Received: from %s (uid %d)\n" 362 "\t(envelope-from %s)\n" 363 "\tid %s\n" 364 "\tby %s (%s);\n" 365 "\t%s\n", 366 username, useruid, 367 queue->sender, 368 queue->id, 369 hostname(), VERSION, 370 rfc822date()); 371 if ((ssize_t)error < 0) 372 return (-1); 373 374 while (!feof(stdin)) { 375 if (fgets(line, sizeof(line) - 1, stdin) == NULL) 376 break; 377 if (had_last_line) 378 errlogx(EX_DATAERR, "bad mail input format:" 379 " from %s (uid %d) (envelope-from %s)", 380 username, useruid, queue->sender); 381 linelen = strlen(line); 382 if (linelen == 0 || line[linelen - 1] != '\n') { 383 /* 384 * This line did not end with a newline character. 385 * If we fix it, it better be the last line of 386 * the file. 387 */ 388 line[linelen] = '\n'; 389 line[linelen + 1] = 0; 390 had_last_line = 1; 391 } 392 if (!had_headers) { 393 /* 394 * Unless this is a continuation, switch of 395 * the Bcc: nocopy flag. 396 */ 397 if (!(line[0] == ' ' || line[0] == '\t')) 398 nocopy = 0; 399 400 if (strprefixcmp(line, "Date:") == 0) 401 had_date = 1; 402 else if (strprefixcmp(line, "Message-Id:") == 0) 403 had_messagid = 1; 404 else if (strprefixcmp(line, "From:") == 0) 405 had_from = 1; 406 else if (strprefixcmp(line, "Bcc:") == 0) 407 nocopy = 1; 408 409 if (parse_state.state != NONE) { 410 if (parse_addrs(&parse_state, line, queue) < 0) { 411 errlogx(EX_DATAERR, "invalid address in header\n"); 412 /* NOTREACHED */ 413 } 414 } 415 416 if (recp_from_header && ( 417 strprefixcmp(line, "To:") == 0 || 418 strprefixcmp(line, "Cc:") == 0 || 419 strprefixcmp(line, "Bcc:") == 0)) { 420 parse_state.state = START; 421 if (parse_addrs(&parse_state, line, queue) < 0) { 422 errlogx(EX_DATAERR, "invalid address in header\n"); 423 /* NOTREACHED */ 424 } 425 } 426 } 427 428 if (strcmp(line, "\n") == 0 && !had_headers) { 429 had_headers = 1; 430 while (!had_date || !had_messagid || !had_from) { 431 if (!had_date) { 432 had_date = 1; 433 snprintf(line, sizeof(line), "Date: %s\n", rfc822date()); 434 } else if (!had_messagid) { 435 /* XXX msgid, assign earlier and log? */ 436 had_messagid = 1; 437 snprintf(line, sizeof(line), "Message-Id: <%"PRIxMAX".%s.%"PRIxMAX"@%s>\n", 438 (uintmax_t)time(NULL), 439 queue->id, 440 (uintmax_t)random(), 441 hostname()); 442 } else if (!had_from) { 443 had_from = 1; 444 snprintf(line, sizeof(line), "From: <%s>\n", queue->sender); 445 } 446 if (fwrite(line, strlen(line), 1, queue->mailf) != 1) 447 return (-1); 448 } 449 strcpy(line, "\n"); 450 } 451 if (!nodot && linelen == 2 && line[0] == '.') 452 break; 453 if (!nocopy) { 454 if (fwrite(line, strlen(line), 1, queue->mailf) != 1) 455 return (-1); 456 } 457 } 458 459 return (0); 460 } 461