ktrace.c revision 1.20 
1/*	$OpenBSD: ktrace.c,v 1.20 2007/03/03 23:46:55 jmc 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. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#ifndef lint
34static char copyright[] =
35"@(#) Copyright (c) 1988, 1993\n\
36	The Regents of the University of California.  All rights reserved.\n";
37#endif /* not lint */
38
39#ifndef lint
40#if 0
41static char sccsid[] = "@(#)ktrace.c	8.2 (Berkeley) 4/28/95";
42#endif
43static char *rcsid = "$OpenBSD: ktrace.c,v 1.20 2007/03/03 23:46:55 jmc Exp $";
44#endif /* not lint */
45
46#include <sys/param.h>
47#include <sys/stat.h>
48#include <sys/time.h>
49#include <sys/uio.h>
50#include <sys/ktrace.h>
51
52#include <err.h>
53#include <errno.h>
54#include <fcntl.h>
55#include <stdlib.h>
56#include <stdio.h>
57#include <string.h>
58#include <unistd.h>
59
60#include "ktrace.h"
61#include "extern.h"
62
63static int rpid(const char *);
64static void no_ktrace(int);
65static void usage(void);
66
67int
68main(int argc, char *argv[])
69{
70	enum { NOTSET, CLEAR, CLEARALL } clear;
71	int append, ch, fd, inherit, ops, pidset, trpoints;
72	pid_t pid;
73	char *tracefile;
74	mode_t omask;
75	struct stat sb;
76
77	clear = NOTSET;
78	append = ops = pidset = inherit = 0;
79	trpoints = DEF_POINTS;
80	tracefile = DEF_TRACEFILE;
81	while ((ch = getopt(argc,argv,"aCcdf:g:ip:t:")) != -1)
82		switch((char)ch) {
83		case 'a':
84			append = 1;
85			break;
86		case 'C':
87			clear = CLEARALL;
88			pidset = 1;
89			break;
90		case 'c':
91			clear = CLEAR;
92			break;
93		case 'd':
94			ops |= KTRFLAG_DESCEND;
95			break;
96		case 'f':
97			tracefile = optarg;
98			break;
99		case 'g':
100			pid = -rpid(optarg);
101			pidset = 1;
102			break;
103		case 'i':
104			inherit = 1;
105			break;
106		case 'p':
107			pid = rpid(optarg);
108			pidset = 1;
109			break;
110		case 't':
111			trpoints = getpoints(optarg);
112			if (trpoints < 0) {
113				warnx("unknown facility in %s", optarg);
114				usage();
115			}
116			break;
117		default:
118			usage();
119		}
120	argv += optind;
121	argc -= optind;
122
123	if ((pidset && *argv) || (!pidset && !*argv && clear != CLEAR))
124		usage();
125
126	if (inherit)
127		trpoints |= KTRFAC_INHERIT;
128
129	(void)signal(SIGSYS, no_ktrace);
130	if (clear != NOTSET) {
131		if (clear == CLEARALL) {
132			ops = KTROP_CLEAR | KTRFLAG_DESCEND;
133			trpoints = ALL_POINTS;
134			pid = 1;
135		} else
136			ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE;
137
138		if (ktrace(tracefile, ops, trpoints, pid) < 0)
139			err(1, "%s", tracefile);
140		exit(0);
141	}
142
143	omask = umask(S_IRWXG|S_IRWXO);
144	if (append) {
145		if ((fd = open(tracefile, O_CREAT | O_WRONLY, DEFFILEMODE)) < 0)
146			err(1, "%s", tracefile);
147		if (fstat(fd, &sb) != 0 || sb.st_uid != getuid())
148			errx(1, "Refuse to append to %s: not owned by you.",
149			    tracefile);
150	} else {
151		if (unlink(tracefile) == -1 && errno != ENOENT)
152			err(1, "unlink %s", tracefile);
153		if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY,
154		    DEFFILEMODE)) < 0)
155			err(1, "%s", tracefile);
156	}
157	(void)umask(omask);
158	(void)close(fd);
159
160	if (*argv) {
161		if (ktrace(tracefile, ops, trpoints, getpid()) < 0)
162			err(1, "%s", tracefile);
163		execvp(argv[0], &argv[0]);
164		err(1, "exec of '%s' failed", argv[0]);
165	}
166	else if (ktrace(tracefile, ops, trpoints, pid) < 0)
167		err(1, "%s", tracefile);
168	exit(0);
169}
170
171static int
172rpid(const char *p)
173{
174	static int first;
175
176	if (first++) {
177		warnx("only one -g or -p flag is permitted.");
178		usage();
179	}
180	if (!*p) {
181		warnx("illegal process id.");
182		usage();
183	}
184	return(atoi(p));
185}
186
187static void
188usage(void)
189{
190	(void)fprintf(stderr,
191	    "usage: ktrace [-aCcdi] [-f trfile] [-g pgid] [-p pid] [-t trstr]\n"
192	    "       ktrace [-adi] [-f trfile] [-t trstr] command\n");
193	exit(1);
194}
195
196/* ARGSUSED */
197static void
198no_ktrace(int signo)
199{
200	char buf[8192];
201
202	snprintf(buf, sizeof(buf),
203"error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'option KTRACE'\n");
204	write(STDERR_FILENO, buf, strlen(buf));
205	_exit(1);
206}
207