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#include <sys/param.h>
33#include <sys/file.h>
34#include <sys/stat.h>
35#include <sys/time.h>
36#include <sys/uio.h>
37#include <sys/ktrace.h>
38
39#include <err.h>
40#include <errno.h>
41#include <inttypes.h>
42#include <stdio.h>
43#include <stdlib.h>
44#include <unistd.h>
45
46#include "ktrace.h"
47
48static char def_tracefile[] = DEF_TRACEFILE;
49
50static enum clear { NOTSET, CLEAR, CLEARALL } clear = NOTSET;
51static int pid;
52
53static void no_ktrace(int);
54static void set_pid_clear(const char *, enum clear);
55static void usage(void) __dead2;
56
57int
58main(int argc, char *argv[])
59{
60	int append, ch, fd, inherit, ops, trpoints;
61	const char *tracefile;
62	mode_t omask;
63	struct stat sb;
64
65	append = ops = inherit = 0;
66	trpoints = DEF_POINTS;
67	tracefile = def_tracefile;
68	while ((ch = getopt(argc,argv,"aCcdf:g:ip:t:")) != -1)
69		switch((char)ch) {
70		case 'a':
71			append = 1;
72			break;
73		case 'C':
74			set_pid_clear("1", CLEARALL);
75			break;
76		case 'c':
77			set_pid_clear(NULL, CLEAR);
78			break;
79		case 'd':
80			ops |= KTRFLAG_DESCEND;
81			break;
82		case 'f':
83			tracefile = optarg;
84			break;
85		case 'g':
86			set_pid_clear(optarg, NOTSET);
87			pid = -pid;
88			break;
89		case 'i':
90			inherit = 1;
91			break;
92		case 'p':
93			set_pid_clear(optarg, NOTSET);
94			break;
95		case 't':
96			trpoints = getpoints(optarg);
97			if (trpoints < 0) {
98				warnx("unknown facility in %s", optarg);
99				usage();
100			}
101			break;
102		default:
103			usage();
104		}
105
106	argv += optind;
107	argc -= optind;
108
109	/* must have either -[Cc], a pid or a command */
110	if (clear == NOTSET && pid == 0 && argc == 0)
111		usage();
112	/* can't have both a pid and a command */
113	/* (note that -C sets pid to 1) */
114	if (pid != 0 && argc > 0) {
115		usage();
116	}
117
118	if (inherit)
119		trpoints |= KTRFAC_INHERIT;
120
121	(void)signal(SIGSYS, no_ktrace);
122	if (clear != NOTSET) {
123		if (clear == CLEARALL) {
124			ops = KTROP_CLEAR | KTRFLAG_DESCEND;
125			trpoints = ALL_POINTS;
126		} else {
127			ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE;
128		}
129		if (ktrace(tracefile, ops, trpoints, pid) < 0)
130			err(1, "%s", tracefile);
131		exit(0);
132	}
133
134	omask = umask(S_IRWXG|S_IRWXO);
135	if (append) {
136		if ((fd = open(tracefile, O_CREAT | O_WRONLY | O_NONBLOCK,
137		    DEFFILEMODE)) < 0)
138			err(1, "%s", tracefile);
139		if (fstat(fd, &sb) != 0 || sb.st_uid != getuid())
140			errx(1, "refuse to append to %s not owned by you",
141			    tracefile);
142		if (!(S_ISREG(sb.st_mode)))
143			errx(1, "%s not regular file", tracefile);
144	} else {
145		if (unlink(tracefile) == -1 && errno != ENOENT)
146			err(1, "unlink %s", tracefile);
147		if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY,
148		    DEFFILEMODE)) < 0)
149			err(1, "%s", tracefile);
150	}
151	(void)umask(omask);
152	(void)close(fd);
153
154	trpoints |= PROC_ABI_POINTS;
155
156	if (argc > 0) {
157		if (ktrace(tracefile, ops, trpoints, getpid()) < 0)
158			err(1, "%s", tracefile);
159		execvp(*argv, argv);
160		err(1, "exec of '%s' failed", *argv);
161	}
162	if (ktrace(tracefile, ops, trpoints, pid) < 0)
163		err(1, "%s", tracefile);
164	exit(0);
165}
166
167static void
168set_pid_clear(const char *p, enum clear cl)
169{
170	intmax_t n;
171	char *e;
172
173	if (clear != NOTSET && cl != NOTSET) {
174		/* either -c and -C or either of them twice */
175		warnx("only one -c or -C flag is permitted");
176		usage();
177	}
178	if ((clear == CLEARALL && p != NULL) || (cl == CLEARALL && pid != 0)) {
179		/* both -C and a pid or pgid */
180		warnx("the -C flag may not be combined with -g or -p");
181		usage();
182	}
183	if (p != NULL && pid != 0) {
184		/* either -p and -g or either of them twice */
185		warnx("only one -g or -p flag is permitted");
186		usage();
187	}
188	if (p != NULL) {
189		errno = 0;
190		n = strtoimax(p, &e, 10);
191		/*
192		 * 1) not a number, or outside the range of an intmax_t
193		 * 2) inside the range of intmax_t but outside the range
194		 *    of an int, keeping in mind that the pid may be
195		 *    negated if it's actually a pgid.
196		 */
197		if (*e != '\0' || n < 1 || errno == ERANGE ||
198		    n > (intmax_t)INT_MAX || n > -(intmax_t)INT_MIN) {
199			warnx("invalid process or group id");
200			usage();
201		}
202		pid = n;
203	}
204	if (cl != NOTSET)
205		if ((clear = cl) == CLEARALL)
206			pid = 1;
207}
208
209static void
210usage(void)
211{
212
213	fprintf(stderr, "%s\n%s\n",
214	    "usage: ktrace [-aCcdi] [-f trfile] [-g pgrp | -p pid] [-t trstr]",
215	    "       ktrace [-adi] [-f trfile] [-t trstr] command");
216	exit(1);
217}
218
219static void
220no_ktrace(int sig __unused)
221{
222
223	fprintf(stderr, "error:\t%s\n\t%s\n",
224	    "ktrace() system call not supported in the running kernel",
225	    "re-compile kernel with 'options KTRACE'");
226        exit(1);
227}
228