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 "dfcompat.h"
37
38#include <sys/file.h>
39#include <sys/stat.h>
40#include <sys/time.h>
41
42#include <ctype.h>
43#include <dirent.h>
44#include <err.h>
45#include <errno.h>
46#include <fcntl.h>
47#include <inttypes.h>
48#include <unistd.h>
49#include <strings.h>
50#include <string.h>
51#include <syslog.h>
52
53#include "dma.h"
54
55/*
56 * Spool file format:
57 *
58 * 'Q'id files (queue):
59 *   Organized like an RFC822 header, field: value.  Ignores unknown fields.
60 *   ID: id
61 *   Sender: envelope-from
62 *   Recipient: envelope-to
63 *
64 * 'M'id files (data):
65 *   mail data
66 *
67 * Each queue file needs to have a corresponding data file.
68 * One data file might be shared by linking it several times.
69 *
70 * Queue ids are unique, formed from the inode of the data file
71 * and a unique identifier.
72 */
73
74int
75newspoolf(struct queue *queue)
76{
77	char fn[PATH_MAX+1];
78	struct stat st;
79	struct stritem *t;
80	int fd;
81
82	if (snprintf(fn, sizeof(fn), "%s/%s", config.spooldir, "tmp_XXXXXXXXXX") <= 0)
83		return (-1);
84
85	fd = mkstemp(fn);
86	if (fd < 0)
87		return (-1);
88	/* XXX group rights */
89	if (fchmod(fd, 0660) < 0)
90		goto fail;
91	if (flock(fd, LOCK_EX) == -1)
92		goto fail;
93	queue->tmpf = strdup(fn);
94	if (queue->tmpf == NULL)
95		goto fail;
96
97	/*
98	 * Assign queue id
99	 */
100	if (fstat(fd, &st) != 0)
101		goto fail;
102	if (asprintf(&queue->id, "%"PRIxMAX, (uintmax_t)st.st_ino) < 0)
103		goto fail;
104
105	queue->mailf = fdopen(fd, "r+");
106	if (queue->mailf == NULL)
107		goto fail;
108
109	t = malloc(sizeof(*t));
110	if (t != NULL) {
111		t->str = queue->tmpf;
112		SLIST_INSERT_HEAD(&tmpfs, t, next);
113	}
114	return (0);
115
116fail:
117	if (queue->mailf != NULL)
118		fclose(queue->mailf);
119	close(fd);
120	unlink(fn);
121	return (-1);
122}
123
124static int
125writequeuef(struct qitem *it)
126{
127	int error;
128	int queuefd;
129
130	queuefd = open_locked(it->queuefn, O_CREAT|O_EXCL|O_RDWR, 0660);
131	if (queuefd == -1)
132		return (-1);
133	if (fchmod(queuefd, 0660) < 0)
134		return (-1);
135	it->queuef = fdopen(queuefd, "w+");
136	if (it->queuef == NULL)
137		return (-1);
138
139	error = fprintf(it->queuef,
140			"ID: %s\n"
141			"Sender: %s\n"
142			"Recipient: %s\n",
143			 it->queueid,
144			 it->sender,
145			 it->addr);
146
147	if (error <= 0)
148		return (-1);
149
150	if (fflush(it->queuef) != 0 || fsync(fileno(it->queuef)) != 0)
151		return (-1);
152
153	return (0);
154}
155
156static struct qitem *
157readqueuef(struct queue *queue, char *queuefn)
158{
159	char line[1000];
160	struct queue itmqueue;
161	FILE *queuef = NULL;
162	char *s;
163	char *queueid = NULL, *sender = NULL, *addr = NULL;
164	struct qitem *it = NULL;
165
166	bzero(&itmqueue, sizeof(itmqueue));
167	LIST_INIT(&itmqueue.queue);
168
169	queuef = fopen(queuefn, "r");
170	if (queuef == NULL)
171		goto out;
172
173	while (!feof(queuef)) {
174		if (fgets(line, sizeof(line), queuef) == NULL || line[0] == 0)
175			break;
176		line[strlen(line) - 1] = 0;	/* chop newline */
177
178		s = strchr(line, ':');
179		if (s == NULL)
180			goto malformed;
181		*s = 0;
182
183		s++;
184		while (isspace(*s))
185			s++;
186
187		s = strdup(s);
188		if (s == NULL)
189			goto malformed;
190
191		if (strcmp(line, "ID") == 0) {
192			queueid = s;
193		} else if (strcmp(line, "Sender") == 0) {
194			sender = s;
195		} else if (strcmp(line, "Recipient") == 0) {
196			addr = s;
197		} else {
198			syslog(LOG_DEBUG, "ignoring unknown queue info `%s' in `%s'",
199			       line, queuefn);
200			free(s);
201		}
202	}
203
204	if (queueid == NULL || sender == NULL || addr == NULL ||
205	    *queueid == 0 || *addr == 0) {
206malformed:
207		errno = EINVAL;
208		syslog(LOG_ERR, "malformed queue file `%s'", queuefn);
209		goto out;
210	}
211
212	if (add_recp(&itmqueue, addr, 0) != 0)
213		goto out;
214
215	it = LIST_FIRST(&itmqueue.queue);
216	it->sender = sender; sender = NULL;
217	it->queueid = queueid; queueid = NULL;
218	it->queuefn = queuefn; queuefn = NULL;
219	LIST_INSERT_HEAD(&queue->queue, it, next);
220
221out:
222	if (sender != NULL)
223		free(sender);
224	if (queueid != NULL)
225		free(queueid);
226	if (addr != NULL)
227		free(addr);
228	if (queuef != NULL)
229		fclose(queuef);
230
231	return (it);
232}
233
234int
235linkspool(struct queue *queue)
236{
237	struct stat st;
238	struct qitem *it;
239
240	if (fflush(queue->mailf) != 0 || fsync(fileno(queue->mailf)) != 0)
241		goto delfiles;
242
243	syslog(LOG_INFO, "new mail from user=%s uid=%d envelope_from=<%s>",
244	       username, getuid(), queue->sender);
245
246	LIST_FOREACH(it, &queue->queue, next) {
247		if (asprintf(&it->queueid, "%s.%"PRIxPTR, queue->id, (uintptr_t)it) <= 0)
248			goto delfiles;
249		if (asprintf(&it->queuefn, "%s/Q%s", config.spooldir, it->queueid) <= 0)
250			goto delfiles;
251		if (asprintf(&it->mailfn, "%s/M%s", config.spooldir, it->queueid) <= 0)
252			goto delfiles;
253
254		/* Neither file may not exist yet */
255		if (stat(it->queuefn, &st) == 0 || stat(it->mailfn, &st) == 0)
256			goto delfiles;
257
258		if (writequeuef(it) != 0)
259			goto delfiles;
260
261		if (link(queue->tmpf, it->mailfn) != 0)
262			goto delfiles;
263	}
264
265	LIST_FOREACH(it, &queue->queue, next) {
266		syslog(LOG_INFO, "mail to=<%s> queued as %s",
267		       it->addr, it->queueid);
268	}
269
270	unlink(queue->tmpf);
271	return (0);
272
273delfiles:
274	LIST_FOREACH(it, &queue->queue, next) {
275		unlink(it->mailfn);
276		unlink(it->queuefn);
277	}
278	return (-1);
279}
280
281int
282load_queue(struct queue *queue)
283{
284	struct stat sb;
285	struct qitem *it;
286	DIR *spooldir;
287	struct dirent *de;
288	char *queuefn;
289	char *mailfn;
290
291	bzero(queue, sizeof(*queue));
292	LIST_INIT(&queue->queue);
293
294	spooldir = opendir(config.spooldir);
295	if (spooldir == NULL)
296		err(EX_NOINPUT, "reading queue");
297
298	while ((de = readdir(spooldir)) != NULL) {
299		queuefn = NULL;
300		mailfn = NULL;
301
302		/* ignore non-queue files */
303		if (de->d_name[0] != 'Q')
304			continue;
305		if (asprintf(&queuefn, "%s/Q%s", config.spooldir, de->d_name + 1) < 0)
306			goto fail;
307		if (asprintf(&mailfn, "%s/M%s", config.spooldir, de->d_name + 1) < 0)
308			goto fail;
309
310		/*
311		 * Some file systems don't provide a de->d_type, so we have to
312		 * do an explicit stat on the queue file.
313		 * Move on if it turns out to be something else than a file.
314		 */
315		if (stat(queuefn, &sb) != 0)
316			goto skip_item;
317		if (!S_ISREG(sb.st_mode)) {
318			errno = EINVAL;
319			goto skip_item;
320		}
321
322		if (stat(mailfn, &sb) != 0)
323			goto skip_item;
324
325		it = readqueuef(queue, queuefn);
326		if (it == NULL)
327			goto skip_item;
328
329		it->mailfn = mailfn;
330		continue;
331
332skip_item:
333		syslog(LOG_INFO, "could not pick up queue file: `%s'/`%s': %m", queuefn, mailfn);
334		if (queuefn != NULL)
335			free(queuefn);
336		if (mailfn != NULL)
337			free(mailfn);
338	}
339	closedir(spooldir);
340	return (0);
341
342fail:
343	return (-1);
344}
345
346void
347delqueue(struct qitem *it)
348{
349	unlink(it->mailfn);
350	unlink(it->queuefn);
351	if (it->queuef != NULL)
352		fclose(it->queuef);
353	if (it->mailf != NULL)
354		fclose(it->mailf);
355	free(it);
356}
357
358int
359acquirespool(struct qitem *it)
360{
361	int queuefd;
362
363	if (it->queuef == NULL) {
364		queuefd = open_locked(it->queuefn, O_RDWR|O_NONBLOCK);
365		if (queuefd < 0)
366			goto fail;
367		it->queuef = fdopen(queuefd, "r+");
368		if (it->queuef == NULL)
369			goto fail;
370	}
371
372	if (it->mailf == NULL) {
373		it->mailf = fopen(it->mailfn, "r");
374		if (it->mailf == NULL)
375			goto fail;
376	}
377
378	return (0);
379
380fail:
381	if (errno == EWOULDBLOCK)
382		return (1);
383	syslog(LOG_INFO, "could not acquire queue file: %m");
384	return (-1);
385}
386
387void
388dropspool(struct queue *queue, struct qitem *keep)
389{
390	struct qitem *it;
391
392	LIST_FOREACH(it, &queue->queue, next) {
393		if (it == keep)
394			continue;
395
396		if (it->queuef != NULL)
397			fclose(it->queuef);
398		if (it->mailf != NULL)
399			fclose(it->mailf);
400	}
401}
402
403int
404flushqueue_since(unsigned int period)
405{
406        struct stat st;
407	struct timeval now;
408        char *flushfn = NULL;
409
410	if (asprintf(&flushfn, "%s/%s", config.spooldir, SPOOL_FLUSHFILE) < 0)
411		return (0);
412	if (stat(flushfn, &st) < 0) {
413		free(flushfn);
414		return (0);
415	}
416	free(flushfn);
417	flushfn = NULL;
418	if (gettimeofday(&now, 0) != 0)
419		return (0);
420
421	/* Did the flush file get touched within the last period seconds? */
422	if (st.st_mtim.tv_sec + (int)period >= now.tv_sec)
423		return (1);
424	else
425		return (0);
426}
427
428int
429flushqueue_signal(void)
430{
431        char *flushfn = NULL;
432	int fd;
433
434        if (asprintf(&flushfn, "%s/%s", config.spooldir, SPOOL_FLUSHFILE) < 0)
435		return (-1);
436	fd = open(flushfn, O_CREAT|O_WRONLY|O_TRUNC, 0660);
437	free(flushfn);
438	if (fd < 0) {
439		syslog(LOG_ERR, "could not open flush file: %m");
440		return (-1);
441	}
442        close(fd);
443	return (0);
444}
445