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 <strings.h>
40 #include <string.h>
41 #include <syslog.h>
42 #include <unistd.h>
43
44 #include "dma.h"
45
46 void
bounce(struct qitem * it,const char * reason)47 bounce(struct qitem *it, const char *reason)
48 {
49 struct queue bounceq;
50 char line[1000];
51 size_t pos;
52 int error;
53
54 /* Don't bounce bounced mails */
55 if (it->sender[0] == 0) {
56 syslog(LOG_INFO, "can not bounce a bounce message, discarding");
57 exit(EX_SOFTWARE);
58 }
59
60 bzero(&bounceq, sizeof(bounceq));
61 LIST_INIT(&bounceq.queue);
62 bounceq.sender = "";
63 if (add_recp(&bounceq, it->sender, EXPAND_WILDCARD) != 0)
64 goto fail;
65
66 if (newspoolf(&bounceq) != 0)
67 goto fail;
68
69 syslog(LOG_ERR, "delivery failed, bouncing as %s", bounceq.id);
70 setlogident("%s", bounceq.id);
71
72 error = fprintf(bounceq.mailf,
73 "Received: from MAILER-DAEMON\n"
74 "\tid %s\n"
75 "\tby %s (%s on %s);\n"
76 "\t%s\n"
77 "X-Original-To: <%s>\n"
78 "From: MAILER-DAEMON <>\n"
79 "To: %s\n"
80 "Subject: Mail delivery failed\n"
81 "Message-Id: <%s@%s>\n"
82 "Date: %s\n"
83 "\n"
84 "This is the %s at %s.\n"
85 "\n"
86 "There was an error delivering your mail to <%s>.\n"
87 "\n"
88 "%s\n"
89 "\n"
90 "%s\n"
91 "\n",
92 bounceq.id,
93 hostname(), VERSION, systemhostname(),
94 rfc822date(),
95 it->addr,
96 it->sender,
97 bounceq.id, hostname(),
98 rfc822date(),
99 VERSION, hostname(),
100 it->addr,
101 reason,
102 config.features & FULLBOUNCE ?
103 "Original message follows." :
104 "Message headers follow.");
105 if (error < 0)
106 goto fail;
107
108 if (fseek(it->mailf, 0, SEEK_SET) != 0)
109 goto fail;
110 if (config.features & FULLBOUNCE) {
111 while ((pos = fread(line, 1, sizeof(line), it->mailf)) > 0) {
112 if (fwrite(line, 1, pos, bounceq.mailf) != pos)
113 goto fail;
114 }
115 } else {
116 while (!feof(it->mailf)) {
117 if (fgets(line, sizeof(line), it->mailf) == NULL)
118 break;
119 if (line[0] == '\n')
120 break;
121 if (fwrite(line, strlen(line), 1, bounceq.mailf) != 1)
122 goto fail;
123 }
124 }
125
126 if (linkspool(&bounceq) != 0)
127 goto fail;
128 /* bounce is safe */
129
130 delqueue(it);
131
132 run_queue(&bounceq);
133 /* NOTREACHED */
134
135 fail:
136 syslog(LOG_CRIT, "error creating bounce: %m");
137 delqueue(it);
138 exit(EX_IOERR);
139 }
140
141 struct parse_state {
142 char addr[1000];
143 int pos;
144
145 enum {
146 NONE = 0,
147 START,
148 MAIN,
149 EOL,
150 QUIT
151 } state;
152 int comment;
153 int quote;
154 int brackets;
155 int esc;
156 };
157
158 /*
159 * Simplified RFC2822 header/address parsing.
160 * We copy escapes and quoted strings directly, since
161 * we have to pass them like this to the mail server anyways.
162 * XXX local addresses will need treatment
163 */
164 static int
parse_addrs(struct parse_state * ps,char * s,struct queue * queue)165 parse_addrs(struct parse_state *ps, char *s, struct queue *queue)
166 {
167 char *addr;
168
169 again:
170 switch (ps->state) {
171 case NONE:
172 return (-1);
173
174 case START:
175 /* init our data */
176 bzero(ps, sizeof(*ps));
177
178 /* skip over header name */
179 while (*s != ':')
180 s++;
181 s++;
182 ps->state = MAIN;
183 break;
184
185 case MAIN:
186 /* all fine */
187 break;
188
189 case EOL:
190 switch (*s) {
191 case ' ':
192 case '\t':
193 ps->state = MAIN;
194 break;
195
196 default:
197 ps->state = QUIT;
198 if (ps->pos != 0)
199 goto newaddr;
200 return (0);
201 }
202 break;
203
204 case QUIT:
205 return (0);
206 }
207
208 for (; *s != 0; s++) {
209 if (ps->esc) {
210 ps->esc = 0;
211
212 switch (*s) {
213 case '\r':
214 case '\n':
215 goto err;
216
217 default:
218 goto copy;
219 }
220 }
221
222 if (ps->quote) {
223 switch (*s) {
224 case '"':
225 ps->quote = 0;
226 goto copy;
227
228 case '\\':
229 ps->esc = 1;
230 goto copy;
231
232 case '\r':
233 case '\n':
234 goto eol;
235
236 default:
237 goto copy;
238 }
239 }
240
241 switch (*s) {
242 case '(':
243 ps->comment++;
244 break;
245
246 case ')':
247 if (ps->comment)
248 ps->comment--;
249 else
250 goto err;
251 goto skip;
252
253 case '"':
254 ps->quote = 1;
255 goto copy;
256
257 case '\\':
258 ps->esc = 1;
259 goto copy;
260
261 case '\r':
262 case '\n':
263 goto eol;
264 }
265
266 if (ps->comment)
267 goto skip;
268
269 switch (*s) {
270 case ' ':
271 case '\t':
272 /* ignore whitespace */
273 goto skip;
274
275 case '<':
276 /* this is the real address now */
277 ps->brackets = 1;
278 ps->pos = 0;
279 goto skip;
280
281 case '>':
282 if (!ps->brackets)
283 goto err;
284 ps->brackets = 0;
285
286 s++;
287 goto newaddr;
288
289 case ':':
290 /* group - ignore */
291 ps->pos = 0;
292 goto skip;
293
294 case ',':
295 case ';':
296 /*
297 * Next address, copy previous one.
298 * However, we might be directly after
299 * a <address>, or have two consecutive
300 * commas.
301 * Skip the comma unless there is
302 * really something to copy.
303 */
304 if (ps->pos == 0)
305 goto skip;
306 s++;
307 goto newaddr;
308
309 default:
310 goto copy;
311 }
312
313 copy:
314 if (ps->comment)
315 goto skip;
316
317 if (ps->pos + 1 == sizeof(ps->addr))
318 goto err;
319 ps->addr[ps->pos++] = *s;
320
321 skip:
322 ;
323 }
324
325 eol:
326 ps->state = EOL;
327 return (0);
328
329 err:
330 ps->state = QUIT;
331 return (-1);
332
333 newaddr:
334 ps->addr[ps->pos] = 0;
335 ps->pos = 0;
336 addr = strdup(ps->addr);
337 if (addr == NULL)
338 errlog(EX_SOFTWARE, "strdup failed");
339
340 if (add_recp(queue, addr, EXPAND_WILDCARD) != 0)
341 errlogx(EX_DATAERR, "invalid recipient `%s'", addr);
342
343 goto again;
344 }
345
346 int
readmail(struct queue * queue,int nodot,int recp_from_header)347 readmail(struct queue *queue, int nodot, int recp_from_header)
348 {
349 struct parse_state parse_state;
350 char line[1000]; /* by RFC2822 */
351 size_t linelen;
352 size_t error;
353 int had_headers = 0;
354 int had_from = 0;
355 int had_messagid = 0;
356 int had_date = 0;
357 int had_first_line = 0;
358 int had_last_line = 0;
359 int nocopy = 0;
360
361 parse_state.state = NONE;
362
363 error = fprintf(queue->mailf,
364 "Received: from %s (uid %d)\n"
365 "\t(envelope-from %s)\n"
366 "\tid %s\n"
367 "\tby %s (%s on %s);\n"
368 "\t%s\n",
369 username, useruid,
370 queue->sender,
371 queue->id,
372 hostname(), VERSION, systemhostname(),
373 rfc822date());
374 if ((ssize_t)error < 0)
375 return (-1);
376
377 while (!feof(stdin)) {
378 if (fgets(line, sizeof(line) - 1, stdin) == NULL)
379 break;
380 if (had_last_line)
381 errlogx(EX_DATAERR, "bad mail input format:"
382 " from %s (uid %d) (envelope-from %s)",
383 username, useruid, queue->sender);
384 linelen = strlen(line);
385 if (linelen == 0 || line[linelen - 1] != '\n') {
386 /*
387 * This line did not end with a newline character.
388 * If we fix it, it better be the last line of
389 * the file.
390 */
391 line[linelen] = '\n';
392 line[linelen + 1] = 0;
393 had_last_line = 1;
394 }
395 if (!had_first_line) {
396 /*
397 * Ignore a leading RFC-976 From_ or >From_ line mistakenly
398 * inserted by some programs.
399 */
400 if (strprefixcmp(line, "From ") == 0 || strprefixcmp(line, ">From ") == 0)
401 continue;
402 had_first_line = 1;
403 }
404 if (!had_headers) {
405 /*
406 * Unless this is a continuation, switch of
407 * the Bcc: nocopy flag.
408 */
409 if (!(line[0] == ' ' || line[0] == '\t'))
410 nocopy = 0;
411
412 if (strprefixcmp(line, "Date:") == 0)
413 had_date = 1;
414 else if (strprefixcmp(line, "Message-Id:") == 0)
415 had_messagid = 1;
416 else if (strprefixcmp(line, "From:") == 0)
417 had_from = 1;
418 else if (strprefixcmp(line, "Bcc:") == 0)
419 nocopy = 1;
420
421 if (parse_state.state != NONE) {
422 if (parse_addrs(&parse_state, line, queue) < 0) {
423 errlogx(EX_DATAERR, "invalid address in header\n");
424 /* NOTREACHED */
425 }
426 }
427
428 if (recp_from_header && (
429 strprefixcmp(line, "To:") == 0 ||
430 strprefixcmp(line, "Cc:") == 0 ||
431 strprefixcmp(line, "Bcc:") == 0)) {
432 parse_state.state = START;
433 if (parse_addrs(&parse_state, line, queue) < 0) {
434 errlogx(EX_DATAERR, "invalid address in header\n");
435 /* NOTREACHED */
436 }
437 }
438 }
439
440 if (strcmp(line, "\n") == 0 && !had_headers) {
441 had_headers = 1;
442 while (!had_date || !had_messagid || !had_from) {
443 if (!had_date) {
444 had_date = 1;
445 snprintf(line, sizeof(line), "Date: %s\n", rfc822date());
446 } else if (!had_messagid) {
447 /* XXX msgid, assign earlier and log? */
448 had_messagid = 1;
449 snprintf(line, sizeof(line), "Message-Id: <%"PRIxMAX".%s.%"PRIxMAX"@%s>\n",
450 (uintmax_t)time(NULL),
451 queue->id,
452 (uintmax_t)random(),
453 hostname());
454 } else if (!had_from) {
455 had_from = 1;
456 snprintf(line, sizeof(line), "From: <%s>\n", queue->sender);
457 }
458 if (fwrite(line, strlen(line), 1, queue->mailf) != 1)
459 return (-1);
460 }
461 strcpy(line, "\n");
462 }
463 if (!nodot && linelen == 2 && line[0] == '.')
464 break;
465 if (!nocopy) {
466 if (fwrite(line, strlen(line), 1, queue->mailf) != 1)
467 return (-1);
468 }
469 }
470
471 return (0);
472 }
473