1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1988, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#ifndef lint
33static const char copyright[] =
34"@(#) Copyright (c) 1988, 1993\n\
35	The Regents of the University of California.  All rights reserved.\n";
36#endif /* not lint */
37
38#if 0
39#ifndef lint
40static char sccsid[] = "@(#)ktrace.c	8.1 (Berkeley) 6/6/93";
41#endif /* not lint */
42#endif
43
44#include <sys/cdefs.h>
45__FBSDID("$FreeBSD$");
46
47#include <sys/param.h>
48#include <sys/file.h>
49#include <sys/stat.h>
50#include <sys/time.h>
51#include <sys/uio.h>
52#include <sys/ktrace.h>
53
54#include <err.h>
55#include <errno.h>
56#include <inttypes.h>
57#include <stdio.h>
58#include <stdlib.h>
59#include <unistd.h>
60
61#include "ktrace.h"
62
63static char def_tracefile[] = DEF_TRACEFILE;
64
65static enum clear { NOTSET, CLEAR, CLEARALL } clear = NOTSET;
66static int pid;
67
68static void no_ktrace(int);
69static void set_pid_clear(const char *, enum clear);
70static void usage(void);
71
72int
73main(int argc, char *argv[])
74{
75	int append, ch, fd, inherit, ops, trpoints;
76	const char *tracefile;
77	mode_t omask;
78	struct stat sb;
79
80	append = ops = inherit = 0;
81	trpoints = DEF_POINTS;
82	tracefile = def_tracefile;
83	while ((ch = getopt(argc,argv,"aCcdf:g:ip:t:")) != -1)
84		switch((char)ch) {
85		case 'a':
86			append = 1;
87			break;
88		case 'C':
89			set_pid_clear("1", CLEARALL);
90			break;
91		case 'c':
92			set_pid_clear(NULL, CLEAR);
93			break;
94		case 'd':
95			ops |= KTRFLAG_DESCEND;
96			break;
97		case 'f':
98			tracefile = optarg;
99			break;
100		case 'g':
101			set_pid_clear(optarg, NOTSET);
102			pid = -pid;
103			break;
104		case 'i':
105			inherit = 1;
106			break;
107		case 'p':
108			set_pid_clear(optarg, NOTSET);
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
121	argv += optind;
122	argc -= optind;
123
124	/* must have either -[Cc], a pid or a command */
125	if (clear == NOTSET && pid == 0 && argc == 0)
126		usage();
127	/* can't have both a pid and a command */
128	/* (note that -C sets pid to 1) */
129	if (pid != 0 && argc > 0) {
130		usage();
131	}
132
133	if (inherit)
134		trpoints |= KTRFAC_INHERIT;
135
136	(void)signal(SIGSYS, no_ktrace);
137	if (clear != NOTSET) {
138		if (clear == CLEARALL) {
139			ops = KTROP_CLEAR | KTRFLAG_DESCEND;
140			trpoints = ALL_POINTS;
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 | O_NONBLOCK,
152		    DEFFILEMODE)) < 0)
153			err(1, "%s", tracefile);
154		if (fstat(fd, &sb) != 0 || sb.st_uid != getuid())
155			errx(1, "refuse to append to %s not owned by you",
156			    tracefile);
157		if (!(S_ISREG(sb.st_mode)))
158			errx(1, "%s not regular file", tracefile);
159	} else {
160		if (unlink(tracefile) == -1 && errno != ENOENT)
161			err(1, "unlink %s", tracefile);
162		if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY,
163		    DEFFILEMODE)) < 0)
164			err(1, "%s", tracefile);
165	}
166	(void)umask(omask);
167	(void)close(fd);
168
169	trpoints |= PROC_ABI_POINTS;
170
171	if (argc > 0) {
172		if (ktrace(tracefile, ops, trpoints, getpid()) < 0)
173			err(1, "%s", tracefile);
174		execvp(*argv, argv);
175		err(1, "exec of '%s' failed", *argv);
176	}
177	if (ktrace(tracefile, ops, trpoints, pid) < 0)
178		err(1, "%s", tracefile);
179	exit(0);
180}
181
182static void
183set_pid_clear(const char *p, enum clear cl)
184{
185	intmax_t n;
186	char *e;
187
188	if (clear != NOTSET && cl != NOTSET) {
189		/* either -c and -C or either of them twice */
190		warnx("only one -c or -C flag is permitted");
191		usage();
192	}
193	if ((clear == CLEARALL && p != NULL) || (cl == CLEARALL && pid != 0)) {
194		/* both -C and a pid or pgid */
195		warnx("the -C flag may not be combined with -g or -p");
196		usage();
197	}
198	if (p != NULL && pid != 0) {
199		/* either -p and -g or either of them twice */
200		warnx("only one -g or -p flag is permitted");
201		usage();
202	}
203	if (p != NULL) {
204		errno = 0;
205		n = strtoimax(p, &e, 10);
206		/*
207		 * 1) not a number, or outside the range of an intmax_t
208		 * 2) inside the range of intmax_t but outside the range
209		 *    of an int, keeping in mind that the pid may be
210		 *    negated if it's actually a pgid.
211		 */
212		if (*e != '\0' || n < 1 || errno == ERANGE ||
213		    n > (intmax_t)INT_MAX || n > -(intmax_t)INT_MIN) {
214			warnx("invalid process or group id");
215			usage();
216		}
217		pid = n;
218	}
219	if (cl != NOTSET)
220		if ((clear = cl) == CLEARALL)
221			pid = 1;
222}
223
224static void
225usage(void)
226{
227
228	fprintf(stderr, "%s\n%s\n",
229	    "usage: ktrace [-aCcdi] [-f trfile] [-g pgrp | -p pid] [-t trstr]",
230	    "       ktrace [-adi] [-f trfile] [-t trstr] command");
231	exit(1);
232}
233
234static void
235no_ktrace(int sig __unused)
236{
237
238	fprintf(stderr, "error:\t%s\n\t%s\n",
239	    "ktrace() system call not supported in the running kernel",
240	    "re-compile kernel with 'options KTRACE'");
241        exit(1);
242}
243