ktrace.c revision 1.15 
1/*	$OpenBSD: ktrace.c,v 1.15 2003/02/19 19:30:13 deraadt 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
38static 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
45static char sccsid[] = "@(#)ktrace.c	8.2 (Berkeley) 4/28/95";
46#endif
47static char *rcsid = "$OpenBSD: ktrace.c,v 1.15 2003/02/19 19:30:13 deraadt 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 <string.h>
62#include <unistd.h>
63
64#include "ktrace.h"
65#include "extern.h"
66
67static int rpid(const char *);
68static void no_ktrace(int);
69static void usage(void);
70
71int
72main(argc, argv)
73	int argc;
74	char **argv;
75{
76	enum { NOTSET, CLEAR, CLEARALL } clear;
77	int append, ch, fd, inherit, ops, pidset, trpoints;
78	pid_t pid;
79	char *tracefile;
80	mode_t omask;
81	struct stat sb;
82
83	clear = NOTSET;
84	append = ops = pidset = inherit = 0;
85	trpoints = DEF_POINTS;
86	tracefile = DEF_TRACEFILE;
87	while ((ch = getopt(argc,argv,"aCcdf:g:ip:t:")) != -1)
88		switch((char)ch) {
89		case 'a':
90			append = 1;
91			break;
92		case 'C':
93			clear = CLEARALL;
94			pidset = 1;
95			break;
96		case 'c':
97			clear = CLEAR;
98			break;
99		case 'd':
100			ops |= KTRFLAG_DESCEND;
101			break;
102		case 'f':
103			tracefile = optarg;
104			break;
105		case 'g':
106			pid = -rpid(optarg);
107			pidset = 1;
108			break;
109		case 'i':
110			inherit = 1;
111			break;
112		case 'p':
113			pid = rpid(optarg);
114			pidset = 1;
115			break;
116		case 't':
117			trpoints = getpoints(optarg);
118			if (trpoints < 0) {
119				warnx("unknown facility in %s", optarg);
120				usage();
121			}
122			break;
123		default:
124			usage();
125		}
126	argv += optind;
127	argc -= optind;
128
129	if ((pidset && *argv) || (!pidset && !*argv && clear != CLEAR))
130		usage();
131
132	if (inherit)
133		trpoints |= KTRFAC_INHERIT;
134
135	(void)signal(SIGSYS, no_ktrace);
136	if (clear != NOTSET) {
137		if (clear == CLEARALL) {
138			ops = KTROP_CLEAR | KTRFLAG_DESCEND;
139			trpoints = ALL_POINTS;
140			pid = 1;
141		} else
142			ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE;
143
144		if (ktrace(tracefile, ops, trpoints, pid) < 0)
145			err(1, "%s", tracefile);
146		exit(0);
147	}
148
149	omask = umask(S_IRWXG|S_IRWXO);
150	if (append) {
151		if ((fd = open(tracefile, O_CREAT | O_WRONLY, DEFFILEMODE)) < 0)
152			err(1, "%s", tracefile);
153		if (fstat(fd, &sb) != 0 || sb.st_uid != getuid())
154			errx(1, "Refuse to append to %s: not owned by you.",
155			    tracefile);
156	} else {
157		if (unlink(tracefile) == -1 && errno != ENOENT)
158			err(1, "unlink %s", tracefile);
159		if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY,
160		    DEFFILEMODE)) < 0)
161			err(1, "%s", tracefile);
162	}
163	(void)umask(omask);
164	(void)close(fd);
165
166	if (*argv) {
167		if (ktrace(tracefile, ops, trpoints, getpid()) < 0)
168			err(1, "%s", tracefile);
169		execvp(argv[0], &argv[0]);
170		err(1, "exec of '%s' failed", argv[0]);
171	}
172	else if (ktrace(tracefile, ops, trpoints, pid) < 0)
173		err(1, "%s", tracefile);
174	exit(0);
175}
176
177static int
178rpid(p)
179	const char *p;
180{
181	static int first;
182
183	if (first++) {
184		warnx("only one -g or -p flag is permitted.");
185		usage();
186	}
187	if (!*p) {
188		warnx("illegal process id.");
189		usage();
190	}
191	return(atoi(p));
192}
193
194static void
195usage()
196{
197	(void)fprintf(stderr,
198"usage:\tktrace [-aCcdi] [-f trfile] [-g pgid] [-p pid] [-t [ceinsw]]\n\tktrace [-adi] [-f trfile] [-t [ceinsw]] command\n");
199	exit(1);
200}
201
202static void
203no_ktrace(sig)
204	int sig;
205{
206	char buf[8192];
207
208	snprintf(buf, sizeof(buf),
209"error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'option KTRACE'\n");
210	write(STDERR_FILENO, buf, strlen(buf));
211	_exit(1);
212}
213