xref: /openbsd/usr.bin/ktrace/ktrace.c (revision d485f761)
1 /*	$OpenBSD: ktrace.c,v 1.11 2001/08/18 00:48:57 espie Exp $	*/
2 /*	$NetBSD: ktrace.c,v 1.4 1995/08/31 23:01:44 jtc Exp $	*/
3 
4 /*-
5  * Copyright (c) 1988, 1993
6  *	The Regents of the University of California.  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  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef lint
38 static char copyright[] =
39 "@(#) Copyright (c) 1988, 1993\n\
40 	The Regents of the University of California.  All rights reserved.\n";
41 #endif /* not lint */
42 
43 #ifndef lint
44 #if 0
45 static char sccsid[] = "@(#)ktrace.c	8.2 (Berkeley) 4/28/95";
46 #endif
47 static char *rcsid = "$OpenBSD: ktrace.c,v 1.11 2001/08/18 00:48:57 espie Exp $";
48 #endif /* not lint */
49 
50 #include <sys/param.h>
51 #include <sys/stat.h>
52 #include <sys/time.h>
53 #include <sys/errno.h>
54 #include <sys/uio.h>
55 #include <sys/ktrace.h>
56 
57 #include <err.h>
58 #include <fcntl.h>
59 #include <stdlib.h>
60 #include <stdio.h>
61 #include <unistd.h>
62 
63 #include "ktrace.h"
64 #include "extern.h"
65 
66 static int rpid __P((const char *));
67 static void no_ktrace __P((int));
68 static void usage __P((void));
69 
70 int
71 main(argc, argv)
72 	int argc;
73 	char **argv;
74 {
75 	enum { NOTSET, CLEAR, CLEARALL } clear;
76 	int append, ch, fd, inherit, ops, pidset, trpoints;
77 	pid_t pid;
78 	char *tracefile;
79 	mode_t omask;
80 	struct stat sb;
81 
82 	clear = NOTSET;
83 	append = ops = pidset = inherit = 0;
84 	trpoints = DEF_POINTS;
85 	tracefile = DEF_TRACEFILE;
86 	while ((ch = getopt(argc,argv,"aCcdf:g:ip:t:")) != -1)
87 		switch((char)ch) {
88 		case 'a':
89 			append = 1;
90 			break;
91 		case 'C':
92 			clear = CLEARALL;
93 			pidset = 1;
94 			break;
95 		case 'c':
96 			clear = CLEAR;
97 			break;
98 		case 'd':
99 			ops |= KTRFLAG_DESCEND;
100 			break;
101 		case 'f':
102 			tracefile = optarg;
103 			break;
104 		case 'g':
105 			pid = -rpid(optarg);
106 			pidset = 1;
107 			break;
108 		case 'i':
109 			inherit = 1;
110 			break;
111 		case 'p':
112 			pid = rpid(optarg);
113 			pidset = 1;
114 			break;
115 		case 't':
116 			trpoints = getpoints(optarg);
117 			if (trpoints < 0) {
118 				warnx("unknown facility in %s", optarg);
119 				usage();
120 			}
121 			break;
122 		default:
123 			usage();
124 		}
125 	argv += optind;
126 	argc -= optind;
127 
128 	if ((pidset && *argv) || (!pidset && !*argv))
129 		usage();
130 
131 	if (inherit)
132 		trpoints |= KTRFAC_INHERIT;
133 
134 	(void)signal(SIGSYS, no_ktrace);
135 	if (clear != NOTSET) {
136 		if (clear == CLEARALL) {
137 			ops = KTROP_CLEAR | KTRFLAG_DESCEND;
138 			trpoints = ALL_POINTS;
139 			pid = 1;
140 		} else
141 			ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE;
142 
143 		if (ktrace(tracefile, ops, trpoints, pid) < 0)
144 			err(1, "%s", tracefile);
145 		exit(0);
146 	}
147 
148 	omask = umask(S_IRWXG|S_IRWXO);
149 	if (append) {
150 		if ((fd = open(tracefile, O_CREAT | O_WRONLY, DEFFILEMODE)) < 0)
151 			err(1, "%s", tracefile);
152 		if (fstat(fd, &sb) != 0 || sb.st_uid != getuid())
153 			errx(1, "Refuse to append to %s: not owned by you.",
154 			    tracefile);
155 	} else {
156 		if (unlink(tracefile) == -1 && errno != ENOENT)
157 			err(1, "unlink %s", tracefile);
158 		if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY,
159 		    DEFFILEMODE)) < 0)
160 			err(1, "%s", tracefile);
161 	}
162 	(void)umask(omask);
163 	(void)close(fd);
164 
165 	if (*argv) {
166 		if (ktrace(tracefile, ops, trpoints, getpid()) < 0)
167 			err(1, "%s", tracefile);
168 		execvp(argv[0], &argv[0]);
169 		err(1, "exec of '%s' failed", argv[0]);
170 	}
171 	else if (ktrace(tracefile, ops, trpoints, pid) < 0)
172 		err(1, "%s", tracefile);
173 	exit(0);
174 }
175 
176 static int
177 rpid(p)
178 	const char *p;
179 {
180 	static int first;
181 
182 	if (first++) {
183 		warnx("only one -g or -p flag is permitted.");
184 		usage();
185 	}
186 	if (!*p) {
187 		warnx("illegal process id.");
188 		usage();
189 	}
190 	return(atoi(p));
191 }
192 
193 static void
194 usage()
195 {
196 	(void)fprintf(stderr,
197 "usage:\tktrace [-aCcid] [-f trfile] [-g pgid] [-p pid] [-t [cenis]\n\tktrace [-aCcid] [-f trfile] [-t [cenis] command\n");
198 	exit(1);
199 }
200 
201 static void
202 no_ktrace(sig)
203 	int sig;
204 {
205 	(void)fprintf(stderr,
206 "error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'options KTRACE'\n");
207 	exit(1);
208 }
209