/usr.bin/ktrace/ktrace.c

  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 * 4. Neither the name of the University nor the names of its contributors
 14 *    may be used to endorse or promote products derived from this software
 15 *    without specific prior written permission.
 16 *
 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 27 * SUCH DAMAGE.
 28 */
 29
 30#ifndef lint
 31static const char copyright[] =
 32"@(#) Copyright (c) 1988, 1993\n\
 33	The Regents of the University of California.  All rights reserved.\n";
 34#endif /* not lint */
 35
 36#if 0
 37#ifndef lint
 38static char sccsid[] = "@(#)ktrace.c	8.1 (Berkeley) 6/6/93";
 39#endif /* not lint */
 40#endif
 41
 42#include <sys/cdefs.h>
 43__FBSDID("$FreeBSD$");
 44
 45#include <sys/param.h>
 46#include <sys/file.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 <inttypes.h>
 55#include <stdio.h>
 56#include <stdlib.h>
 57#include <unistd.h>
 58
 59#include "ktrace.h"
 60
 61static char def_tracefile[] = DEF_TRACEFILE;
 62
 63static enum clear { NOTSET, CLEAR, CLEARALL } clear = NOTSET;
 64static int pid;
 65
 66static void no_ktrace(int);
 67static void set_pid_clear(const char *, enum clear);
 68static void usage(void);
 69
 70int
 71main(int argc, char *argv[])
 72{
 73	int append, ch, fd, inherit, ops, trpoints;
 74	const char *tracefile;
 75	mode_t omask;
 76	struct stat sb;
 77
 78	append = ops = 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			set_pid_clear("1", CLEARALL);
 88			break;
 89		case 'c':
 90			set_pid_clear(NULL, CLEAR);
 91			break;
 92		case 'd':
 93			ops |= KTRFLAG_DESCEND;
 94			break;
 95		case 'f':
 96			tracefile = optarg;
 97			break;
 98		case 'g':
 99			set_pid_clear(optarg, NOTSET);
100			pid = -pid;
101			break;
102		case 'i':
103			inherit = 1;
104			break;
105		case 'p':
106			set_pid_clear(optarg, NOTSET);
107			break;
108		case 't':
109			trpoints = getpoints(optarg);
110			if (trpoints < 0) {
111				warnx("unknown facility in %s", optarg);
112				usage();
113			}
114			break;
115		default:
116			usage();
117		}
118
119	argv += optind;
120	argc -= optind;
121
122	/* must have either -[Cc], a pid or a command */
123	if (clear == NOTSET && pid == 0 && argc == 0)
124		usage();
125	/* can't have both a pid and a command */
126	/* (note that -C sets pid to 1) */
127	if (pid != 0 && argc > 0) {
128		usage();
129	}
130
131	if (inherit)
132		trpoints |= KTRFAC_INHERIT;
133
134	(void)signal(SIGSYS, no_ktrace);
135	if (clear != NOTSET) {
136		if (clear == CLEARALL) {
137			ops = KTROP_CLEAR | KTRFLAG_DESCEND;
138			trpoints = ALL_POINTS;
139		} else {
140			ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE;
141		}
142		if (ktrace(tracefile, ops, trpoints, pid) < 0)
143			err(1, "%s", tracefile);
144		exit(0);
145	}
146
147	omask = umask(S_IRWXG|S_IRWXO);
148	if (append) {
149		if ((fd = open(tracefile, O_CREAT | O_WRONLY | O_NONBLOCK,
150		    DEFFILEMODE)) < 0)
151			err(1, "%s", tracefile);
152		if (fstat(fd, &sb) != 0 || sb.st_uid != getuid())
153			errx(1, "refuse to append to %s not owned by you",
154			    tracefile);
155		if (!(S_ISREG(sb.st_mode)))
156			errx(1, "%s not regular file", tracefile);
157	} else {
158		if (unlink(tracefile) == -1 && errno != ENOENT)
159			err(1, "unlink %s", tracefile);
160		if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY,
161		    DEFFILEMODE)) < 0)
162			err(1, "%s", tracefile);
163	}
164	(void)umask(omask);
165	(void)close(fd);
166
167	trpoints |= PROC_ABI_POINTS;
168
169	if (argc > 0) { 
170		if (ktrace(tracefile, ops, trpoints, getpid()) < 0)
171			err(1, "%s", tracefile);
172		execvp(*argv, argv);
173		err(1, "exec of '%s' failed", *argv);
174	}
175	if (ktrace(tracefile, ops, trpoints, pid) < 0)
176		err(1, "%s", tracefile);
177	exit(0);
178}
179
180static void
181set_pid_clear(const char *p, enum clear cl)
182{
183	intmax_t n;
184	char *e;
185
186	if (clear != NOTSET && cl != NOTSET) {
187		/* either -c and -C or either of them twice */
188		warnx("only one -c or -C flag is permitted");
189		usage();
190	}
191	if ((clear == CLEARALL && p != NULL) || (cl == CLEARALL && pid != 0)) {
192		/* both -C and a pid or pgid */
193		warnx("the -C flag may not be combined with -g or -p");
194		usage();
195	}
196	if (p != NULL && pid != 0) {
197		/* either -p and -g or either of them twice */
198		warnx("only one -g or -p flag is permitted");
199		usage();
200	}
201	if (p != NULL) {
202		errno = 0;
203		n = strtoimax(p, &e, 10);
204		/*
205		 * 1) not a number, or outside the range of an intmax_t
206		 * 2) inside the range of intmax_t but outside the range
207		 *    of an int, keeping in mind that the pid may be
208		 *    negated if it's actually a pgid.
209		 */
210		if (*e != '\0' || n < 1 || errno == ERANGE ||
211		    n > (intmax_t)INT_MAX || n > -(intmax_t)INT_MIN) {
212			warnx("invalid process or group id");
213			usage();
214		}
215		pid = n;
216	}
217	if (cl != NOTSET)
218		if ((clear = cl) == CLEARALL)
219			pid = 1;
220}
221
222static void
223usage(void)
224{
225
226	fprintf(stderr, "%s\n%s\n",
227	    "usage: ktrace [-aCcdi] [-f trfile] [-g pgrp | -p pid] [-t trstr]",
228	    "       ktrace [-adi] [-f trfile] [-t trstr] command");
229	exit(1);
230}
231
232static void
233no_ktrace(int sig __unused)
234{
235
236	fprintf(stderr, "error:\t%s\n\t%s\n",
237	    "ktrace() system call not supported in the running kernel",
238	    "re-compile kernel with 'options KTRACE'");
239        exit(1);
240}