1 /* $OpenBSD: ktrace.c,v 1.27 2013/11/06 17:26:55 sobrado 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 #include <sys/param.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 <fcntl.h> 42 #include <stdlib.h> 43 #include <stdio.h> 44 #include <string.h> 45 #include <unistd.h> 46 47 #include "ktrace.h" 48 #include "extern.h" 49 50 extern char *__progname; 51 52 static int rpid(const char *); 53 static void no_ktrace(int); 54 static void usage(void); 55 56 int is_ltrace; 57 58 int 59 main(int argc, char *argv[]) 60 { 61 enum { NOTSET, CLEAR, CLEARALL } clear; 62 int append, ch, fd, inherit, ops, pidset, trpoints; 63 pid_t pid; 64 char *tracefile, *tracespec; 65 mode_t omask; 66 struct stat sb; 67 68 is_ltrace = strcmp(__progname, "ltrace") == 0; 69 70 clear = NOTSET; 71 append = ops = pidset = inherit = pid = 0; 72 trpoints = is_ltrace ? KTRFAC_USER : DEF_POINTS; 73 tracefile = DEF_TRACEFILE; 74 tracespec = NULL; 75 76 if (is_ltrace) { 77 while ((ch = getopt(argc, argv, "af:iu:")) != -1) 78 switch ((char)ch) { 79 case 'a': 80 append = 1; 81 break; 82 case 'f': 83 tracefile = optarg; 84 break; 85 case 'i': 86 inherit = 1; 87 break; 88 case 'u': 89 tracespec = optarg; 90 break; 91 default: 92 usage(); 93 } 94 } else { 95 while ((ch = getopt(argc, argv, "aBCcdf:g:ip:t:")) != -1) 96 switch ((char)ch) { 97 case 'a': 98 append = 1; 99 break; 100 case 'B': 101 putenv("LD_BIND_NOW="); 102 break; 103 case 'C': 104 clear = CLEARALL; 105 pidset = 1; 106 break; 107 case 'c': 108 clear = CLEAR; 109 break; 110 case 'd': 111 ops |= KTRFLAG_DESCEND; 112 break; 113 case 'f': 114 tracefile = optarg; 115 break; 116 case 'g': 117 pid = -rpid(optarg); 118 pidset = 1; 119 break; 120 case 'i': 121 inherit = 1; 122 break; 123 case 'p': 124 pid = rpid(optarg); 125 pidset = 1; 126 break; 127 case 't': 128 trpoints = getpoints(optarg); 129 if (trpoints < 0) { 130 warnx("unknown facility in %s", optarg); 131 usage(); 132 } 133 break; 134 default: 135 usage(); 136 } 137 } 138 139 argv += optind; 140 argc -= optind; 141 142 if ((pidset && *argv) || (!pidset && !*argv && clear != CLEAR)) 143 usage(); 144 145 if (inherit) 146 trpoints |= KTRFAC_INHERIT; 147 148 (void)signal(SIGSYS, no_ktrace); 149 if (clear != NOTSET) { 150 if (clear == CLEARALL) { 151 ops = KTROP_CLEAR | KTRFLAG_DESCEND; 152 trpoints = ALL_POINTS; 153 pid = 1; 154 } else 155 ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE; 156 157 if (ktrace(tracefile, ops, trpoints, pid) < 0) 158 err(1, "%s", tracefile); 159 exit(0); 160 } 161 162 omask = umask(S_IRWXG|S_IRWXO); 163 if (append) { 164 if ((fd = open(tracefile, O_CREAT | O_WRONLY, DEFFILEMODE)) < 0) 165 err(1, "%s", tracefile); 166 if (fstat(fd, &sb) != 0 || sb.st_uid != getuid()) 167 errx(1, "Refuse to append to %s: not owned by you.", 168 tracefile); 169 } else { 170 if (unlink(tracefile) == -1 && errno != ENOENT) 171 err(1, "unlink %s", tracefile); 172 if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY, 173 DEFFILEMODE)) < 0) 174 err(1, "%s", tracefile); 175 } 176 (void)umask(omask); 177 (void)close(fd); 178 179 if (*argv) { 180 if (is_ltrace) { 181 if (setenv("LD_TRACE_PLT", inherit ? "i" : "", 1) < 0) 182 err(1, "setenv(LD_TRACE_PLT)"); 183 if (tracespec && 184 setenv("LD_TRACE_PLTSPEC", tracespec, 1) < 0) 185 err(1, "setenv(LD_TRACE_PLTSPEC)"); 186 } 187 if (ktrace(tracefile, ops, trpoints, getpid()) < 0) 188 err(1, "%s", tracefile); 189 execvp(argv[0], &argv[0]); 190 err(1, "exec of '%s' failed", argv[0]); 191 } 192 else if (ktrace(tracefile, ops, trpoints, pid) < 0) 193 err(1, "%s", tracefile); 194 exit(0); 195 } 196 197 static int 198 rpid(const char *p) 199 { 200 static int first; 201 202 if (first++) { 203 warnx("only one -g or -p flag is permitted."); 204 usage(); 205 } 206 if (!*p) { 207 warnx("illegal process id."); 208 usage(); 209 } 210 return(atoi(p)); 211 } 212 213 static void 214 usage(void) 215 { 216 if (is_ltrace) 217 fprintf(stderr, "usage: %s [-ai] [-f trfile] [-u trspec]" 218 " command\n", 219 __progname); 220 else 221 fprintf(stderr, "usage: %s [-aBCcdi] [-f trfile] [-g pgid]" 222 " [-p pid] [-t trstr]\n" 223 " %s [-adi] [-f trfile] [-t trstr] command\n", 224 __progname, __progname); 225 exit(1); 226 } 227 228 /* ARGSUSED */ 229 static void 230 no_ktrace(int signo) 231 { 232 char buf[8192]; 233 234 snprintf(buf, sizeof(buf), 235 "error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'option KTRACE'\n"); 236 write(STDERR_FILENO, buf, strlen(buf)); 237 _exit(1); 238 } 239