xref: /freebsd/usr.bin/ktrace/ktrace.c (revision 952d112864d8008aa87278a30a539d888a8493cd)
1 /*-
2  * Copyright (c) 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static char copyright[] =
36 "@(#) Copyright (c) 1988, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)ktrace.c	8.1 (Berkeley) 6/6/93";
43 #endif
44 static const char rcsid[] =
45 	"$Id: ktrace.c,v 1.9 1997/03/15 10:39:12 joerg Exp $";
46 #endif /* not lint */
47 
48 #include <sys/param.h>
49 #include <sys/stat.h>
50 #include <sys/file.h>
51 #include <sys/time.h>
52 #include <sys/errno.h>
53 #include <sys/uio.h>
54 #include <sys/ktrace.h>
55 
56 #include <err.h>
57 #include <stdio.h>
58 #include <unistd.h>
59 
60 #include "ktrace.h"
61 
62 void no_ktrace __P((int));
63 void usage __P((void));
64 
65 main(argc, argv)
66 	int argc;
67 	char **argv;
68 {
69 	extern int optind;
70 	extern char *optarg;
71 	enum { NOTSET, CLEAR, CLEARALL } clear;
72 	int append, ch, fd, inherit, ops, pid, pidset, trpoints;
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)
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, 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, 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, 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, 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, tracefile);
168 	exit(0);
169 }
170 
171 rpid(p)
172 	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 
187 void
188 usage()
189 {
190 	(void)fprintf(stderr,
191 "usage:\tktrace [-aCcid] [-f trfile] [-g pgid] [-p pid] [-t [cnisuv]\n\tktrace [-aCcid] [-f trfile] [-t [cnisuw] command\n");
192 	exit(1);
193 }
194 
195 void
196 no_ktrace(sig)
197         int sig;
198 {
199         (void)fprintf(stderr,
200 "error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'options KTRACE'\n");
201         exit(1);
202 }
203