xref: /openbsd-src/usr.sbin/smtpd/mail.mboxfile.c (revision f1dd7b858388b4a23f4f67a4957ec5ff656ebbe8)
1 /*
2  * Copyright (c) 2018 Gilles Chehade <gilles@poolp.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/types.h>
18 #include <sys/stat.h>
19 
20 #include <ctype.h>
21 #include <err.h>
22 #include <errno.h>
23 #include <fcntl.h>
24 #include <limits.h>
25 #include <netdb.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sysexits.h>
30 #include <unistd.h>
31 
32 static void	mboxfile_engine(const char *sender, const char *filename);
33 
34 int
35 main(int argc, char *argv[])
36 {
37 	int	ch;
38 	char   *sender = "<unknown>";
39 
40 	if (! geteuid())
41 		errx(1, "mail.mboxfile: may not be executed as root");
42 
43 	while ((ch = getopt(argc, argv, "f:")) != -1) {
44 		switch (ch) {
45 		case 'f':
46 			sender = optarg;
47 			break;
48 		default:
49 			break;
50 		}
51 	}
52 	argc -= optind;
53 	argv += optind;
54 
55 	if (argc > 1)
56 		errx(1, "mail.mboxfile: only one mboxfile is allowed");
57 
58 	mboxfile_engine(sender, argv[0]);
59 
60 	return (0);
61 }
62 
63 static void
64 mboxfile_engine(const char *sender, const char *filename)
65 {
66 	int	fd;
67 	FILE    *fp;
68 	char	*line = NULL;
69 	size_t	linesize = 0;
70 	time_t	now;
71 
72 	time(&now);
73 
74 	fd = open(filename, O_CREAT | O_APPEND | O_WRONLY | O_EXLOCK, 0600);
75 	if (fd == -1)
76 		err(EX_TEMPFAIL, NULL);
77 
78 	if ((fp = fdopen(fd, "w")) == NULL)
79 		err(EX_TEMPFAIL, NULL);
80 
81 	fprintf(fp, "From %s %s", sender, ctime(&now));
82 	while (getline(&line, &linesize, stdin) != -1) {
83 		line[strcspn(line, "\n")] = '\0';
84 		if (strncmp(line, "From ", 5) == 0)
85 			fprintf(fp, ">%s\n", line);
86 		else
87 			fprintf(fp, "%s\n", line);
88 	}
89 	fprintf(fp, "\n");
90 	free(line);
91 	if (ferror(stdin))
92 		err(EX_TEMPFAIL, NULL);
93 
94 	if (fflush(fp) == EOF ||
95 	    ferror(fp) ||
96 	    (fsync(fd) == -1 && errno != EINVAL) ||
97 	    fclose(fp) == EOF)
98 		err(EX_TEMPFAIL, NULL);
99 }
100