xref: /openbsd/usr.sbin/smtpd/mail.mboxfile.c (revision 73471bf0)
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 
19 #include <err.h>
20 #include <errno.h>
21 #include <fcntl.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <sysexits.h>
26 #include <time.h>
27 #include <unistd.h>
28 
29 static void	mboxfile_engine(const char *sender, const char *filename);
30 
31 int
32 main(int argc, char *argv[])
33 {
34 	int	ch;
35 	char   *sender = "<unknown>";
36 
37 	if (! geteuid())
38 		errx(1, "mail.mboxfile: may not be executed as root");
39 
40 	while ((ch = getopt(argc, argv, "f:")) != -1) {
41 		switch (ch) {
42 		case 'f':
43 			sender = optarg;
44 			break;
45 		default:
46 			break;
47 		}
48 	}
49 	argc -= optind;
50 	argv += optind;
51 
52 	if (argc > 1)
53 		errx(1, "mail.mboxfile: only one mboxfile is allowed");
54 
55 	mboxfile_engine(sender, argv[0]);
56 
57 	return (0);
58 }
59 
60 static void
61 mboxfile_engine(const char *sender, const char *filename)
62 {
63 	int	fd;
64 	FILE    *fp;
65 	char	*line = NULL;
66 	size_t	linesize = 0;
67 	time_t	now;
68 
69 	time(&now);
70 
71 	fd = open(filename, O_CREAT | O_APPEND | O_WRONLY | O_EXLOCK, 0600);
72 	if (fd == -1)
73 		err(EX_TEMPFAIL, NULL);
74 
75 	if ((fp = fdopen(fd, "w")) == NULL)
76 		err(EX_TEMPFAIL, NULL);
77 
78 	fprintf(fp, "From %s %s", sender, ctime(&now));
79 	while (getline(&line, &linesize, stdin) != -1) {
80 		line[strcspn(line, "\n")] = '\0';
81 		if (strncmp(line, "From ", 5) == 0)
82 			fprintf(fp, ">%s\n", line);
83 		else
84 			fprintf(fp, "%s\n", line);
85 	}
86 	fprintf(fp, "\n");
87 	free(line);
88 	if (ferror(stdin))
89 		err(EX_TEMPFAIL, NULL);
90 
91 	if (fflush(fp) == EOF ||
92 	    ferror(fp) ||
93 	    (fsync(fd) == -1 && errno != EINVAL) ||
94 	    fclose(fp) == EOF)
95 		err(EX_TEMPFAIL, NULL);
96 }
97