1/*
2 * Copyright (c) 1988, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 *    may be used to endorse or promote products derived from this software
15 *    without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#ifndef lint
31static const char copyright[] =
32"@(#) Copyright (c) 1988, 1993\n\
33	The Regents of the University of California.  All rights reserved.\n";
34#endif /* not lint */
35
36#ifndef lint
37#if 0
38static char sccsid[] = "@(#)tee.c	8.1 (Berkeley) 6/6/93";
39#endif
40static const char rcsid[] =
41  "$FreeBSD: stable/11/usr.bin/tee/tee.c 307773 2016-10-22 13:20:02Z bapt $";
42#endif /* not lint */
43
44#include <sys/capsicum.h>
45#include <sys/stat.h>
46#include <sys/types.h>
47
48#include <err.h>
49#include <errno.h>
50#include <fcntl.h>
51#include <signal.h>
52#include <stdio.h>
53#include <stdlib.h>
54#include <string.h>
55#include <termios.h>
56#include <unistd.h>
57
58typedef struct _list {
59	struct _list *next;
60	int fd;
61	const char *name;
62} LIST;
63static LIST *head;
64
65static void add(int, const char *);
66static void usage(void);
67
68int
69main(int argc, char *argv[])
70{
71	LIST *p;
72	int n, fd, rval, wval;
73	char *bp;
74	int append, ch, exitval;
75	char *buf;
76	cap_rights_t rights;
77	unsigned long cmd;
78#define	BSIZE (8 * 1024)
79
80	append = 0;
81	while ((ch = getopt(argc, argv, "ai")) != -1)
82		switch((char)ch) {
83		case 'a':
84			append = 1;
85			break;
86		case 'i':
87			(void)signal(SIGINT, SIG_IGN);
88			break;
89		case '?':
90		default:
91			usage();
92		}
93	argv += optind;
94	argc -= optind;
95
96	if ((buf = malloc(BSIZE)) == NULL)
97		err(1, "malloc");
98
99	cap_rights_init(&rights, CAP_READ, CAP_FSTAT);
100	if (cap_rights_limit(STDIN_FILENO, &rights) < 0 && errno != ENOSYS)
101		err(EXIT_FAILURE, "unable to limit rights for stdin");
102	cap_rights_init(&rights, CAP_WRITE, CAP_FSTAT, CAP_IOCTL);
103	if (cap_rights_limit(STDERR_FILENO, &rights) < 0 && errno != ENOSYS)
104		err(EXIT_FAILURE, "unable to limit rights for stderr");
105	cmd = TIOCGETA;
106	if (cap_ioctls_limit(STDERR_FILENO, &cmd, 1) < 0 && errno != ENOSYS)
107		err(EXIT_FAILURE, "unable to limit ioctls for stderr");
108
109	add(STDOUT_FILENO, "stdout");
110
111	for (exitval = 0; *argv; ++argv)
112		if ((fd = open(*argv, append ? O_WRONLY|O_CREAT|O_APPEND :
113		    O_WRONLY|O_CREAT|O_TRUNC, DEFFILEMODE)) < 0) {
114			warn("%s", *argv);
115			exitval = 1;
116		} else
117			add(fd, *argv);
118
119	if (cap_enter() < 0 && errno != ENOSYS)
120		err(EXIT_FAILURE, "unable to enter capability mode");
121	while ((rval = read(STDIN_FILENO, buf, BSIZE)) > 0)
122		for (p = head; p; p = p->next) {
123			n = rval;
124			bp = buf;
125			do {
126				if ((wval = write(p->fd, bp, n)) == -1) {
127					warn("%s", p->name);
128					exitval = 1;
129					break;
130				}
131				bp += wval;
132			} while (n -= wval);
133		}
134	if (rval < 0)
135		err(1, "read");
136	exit(exitval);
137}
138
139static void
140usage(void)
141{
142	(void)fprintf(stderr, "usage: tee [-ai] [file ...]\n");
143	exit(1);
144}
145
146static void
147add(int fd, const char *name)
148{
149	LIST *p;
150	cap_rights_t rights;
151	unsigned long cmd;
152
153	if (fd == STDOUT_FILENO)
154		cap_rights_init(&rights, CAP_WRITE, CAP_FSTAT, CAP_IOCTL);
155	else
156		cap_rights_init(&rights, CAP_WRITE, CAP_FSTAT);
157	if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS)
158		err(EXIT_FAILURE, "unable to limit rights");
159
160	if (fd == STDOUT_FILENO) {
161		cmd = TIOCGETA;
162		if (cap_ioctls_limit(fd, &cmd, 1) < 0 && errno != ENOSYS)
163			err(EXIT_FAILURE, "unable to limit ioctls for stdout");
164	}
165
166	if ((p = malloc(sizeof(LIST))) == NULL)
167		err(1, "malloc");
168	p->fd = fd;
169	p->name = name;
170	p->next = head;
171	head = p;
172}
173