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