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