xref: /freebsd/usr.bin/protect/protect.c (revision 031beb4e239bfce798af17f5fe8dba8bcaf13d99)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2013 Hudson River Trading LLC
5  * Written by: John H. Baldwin <jhb@FreeBSD.org>
6  * All rights reserved.
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  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 #include <sys/cdefs.h>
31 #include <sys/procctl.h>
32 #include <sys/types.h>
33 #include <sys/mman.h>
34 #include <err.h>
35 #include <errno.h>
36 #include <stdbool.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <unistd.h>
40 
41 static void
42 usage(void)
43 {
44 
45 	fprintf(stderr, "usage: protect [-i] command\n");
46 	fprintf(stderr, "       protect [-cdi] -g pgrp | -p pid\n");
47 	exit(1);
48 }
49 
50 static id_t
51 parse_id(char *id)
52 {
53 	static bool first = true;
54 	long value;
55 	char *ch;
56 
57 	if (!first) {
58 		warnx("only one -g or -p flag is permitted");
59 		usage();
60 	}
61 	value = strtol(id, &ch, 0);
62 	if (*ch != '\0') {
63 		warnx("invalid process id");
64 		usage();
65 	}
66 	return (value);
67 }
68 
69 int
70 main(int argc, char *argv[])
71 {
72 	idtype_t idtype;
73 	id_t id;
74 	int ch, flags;
75 	bool descend, inherit, idset;
76 
77 	idtype = P_PID;
78 	id = getpid();
79 	flags = PPROT_SET;
80 	descend = inherit = idset = false;
81 	while ((ch = getopt(argc, argv, "cdig:p:")) != -1)
82 		switch (ch) {
83 		case 'c':
84 			flags = PPROT_CLEAR;
85 			break;
86 		case 'd':
87 			descend = true;
88 			break;
89 		case 'i':
90 			inherit = true;
91 			break;
92 		case 'g':
93 			idtype = P_PGID;
94 			id = parse_id(optarg);
95 			idset = true;
96 			break;
97 		case 'p':
98 			idtype = P_PID;
99 			id = parse_id(optarg);
100 			idset = true;
101 			break;
102 		}
103 	argc -= optind;
104 	argv += optind;
105 
106 	if ((idset && argc != 0) || (!idset && (argc == 0 || descend)))
107 		usage();
108 
109 	if (descend)
110 		flags |= PPROT_DESCEND;
111 	if (inherit)
112 		flags |= PPROT_INHERIT;
113 	if (procctl(idtype, id, PROC_SPROTECT, &flags) == -1)
114 		err(1, "procctl");
115 
116 	if (argc != 0) {
117 		errno = 0;
118 		execvp(*argv, argv);
119 		err(errno == ENOENT ? 127 : 126, "%s", *argv);
120 	}
121 	return (0);
122 }
123