1 /* $OpenBSD: ktrace.c,v 1.30 2014/05/24 17:04:16 deraadt 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:it:u:")) != -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 't': 89 trpoints = getpoints(optarg); 90 if (trpoints < 0) { 91 warnx("unknown facility in %s", optarg); 92 usage(); 93 } 94 break; 95 case 'u': 96 tracespec = optarg; 97 break; 98 default: 99 usage(); 100 } 101 } else { 102 while ((ch = getopt(argc, argv, "aBCcdf:g:ip:t:")) != -1) 103 switch ((char)ch) { 104 case 'a': 105 append = 1; 106 break; 107 case 'B': 108 putenv("LD_BIND_NOW="); 109 break; 110 case 'C': 111 clear = CLEARALL; 112 pidset = 1; 113 break; 114 case 'c': 115 clear = CLEAR; 116 break; 117 case 'd': 118 ops |= KTRFLAG_DESCEND; 119 break; 120 case 'f': 121 tracefile = optarg; 122 break; 123 case 'g': 124 pid = -rpid(optarg); 125 pidset = 1; 126 break; 127 case 'i': 128 inherit = 1; 129 break; 130 case 'p': 131 pid = rpid(optarg); 132 pidset = 1; 133 break; 134 case 't': 135 trpoints = getpoints(optarg); 136 if (trpoints < 0) { 137 warnx("unknown facility in %s", optarg); 138 usage(); 139 } 140 break; 141 default: 142 usage(); 143 } 144 } 145 146 argv += optind; 147 argc -= optind; 148 149 if ((pidset && *argv) || (!pidset && !*argv && clear != CLEAR)) 150 usage(); 151 152 if (inherit) 153 trpoints |= KTRFAC_INHERIT; 154 155 (void)signal(SIGSYS, no_ktrace); 156 if (clear != NOTSET) { 157 if (clear == CLEARALL) { 158 ops = KTROP_CLEAR | KTRFLAG_DESCEND; 159 trpoints = ALL_POINTS; 160 pid = 1; 161 } else 162 ops |= pid ? KTROP_CLEAR : KTROP_CLEARFILE; 163 164 if (ktrace(tracefile, ops, trpoints, pid) < 0) { 165 if (errno == ESRCH) 166 err(1, "%d", pid); 167 err(1, "%s", tracefile); 168 } 169 exit(0); 170 } 171 172 omask = umask(S_IRWXG|S_IRWXO); 173 if (append) { 174 if ((fd = open(tracefile, O_CREAT | O_WRONLY, DEFFILEMODE)) < 0) 175 err(1, "%s", tracefile); 176 if (fstat(fd, &sb) != 0 || sb.st_uid != getuid()) 177 errx(1, "Refuse to append to %s: not owned by you.", 178 tracefile); 179 } else { 180 if (unlink(tracefile) == -1 && errno != ENOENT) 181 err(1, "unlink %s", tracefile); 182 if ((fd = open(tracefile, O_CREAT | O_EXCL | O_WRONLY, 183 DEFFILEMODE)) < 0) 184 err(1, "%s", tracefile); 185 } 186 (void)umask(omask); 187 (void)close(fd); 188 189 if (*argv) { 190 if (is_ltrace) { 191 if (setenv("LD_TRACE_PLT", inherit ? "i" : "", 1) < 0) 192 err(1, "setenv(LD_TRACE_PLT)"); 193 if (tracespec && 194 setenv("LD_TRACE_PLTSPEC", tracespec, 1) < 0) 195 err(1, "setenv(LD_TRACE_PLTSPEC)"); 196 } 197 if (ktrace(tracefile, ops, trpoints, getpid()) < 0) 198 err(1, "%s", tracefile); 199 execvp(argv[0], &argv[0]); 200 err(1, "exec of '%s' failed", argv[0]); 201 } 202 else if (ktrace(tracefile, ops, trpoints, pid) < 0) { 203 if (errno == ESRCH) 204 err(1, "%d", pid); 205 err(1, "%s", tracefile); 206 } 207 exit(0); 208 } 209 210 static int 211 rpid(const char *p) 212 { 213 static int first; 214 215 if (first++) { 216 warnx("only one -g or -p flag is permitted."); 217 usage(); 218 } 219 if (!*p) { 220 warnx("illegal process id."); 221 usage(); 222 } 223 return(atoi(p)); 224 } 225 226 static void 227 usage(void) 228 { 229 if (is_ltrace) 230 fprintf(stderr, "usage: %s [-ai] [-f trfile] [-t trstr]" 231 " [-u trspec] command\n", 232 __progname); 233 else 234 fprintf(stderr, "usage: %s [-aBCcdi] [-f trfile] [-g pgid]" 235 " [-p pid] [-t trstr]\n" 236 " %s [-adi] [-f trfile] [-t trstr] command\n", 237 __progname, __progname); 238 exit(1); 239 } 240 241 /* ARGSUSED */ 242 static void 243 no_ktrace(int signo) 244 { 245 char buf[8192]; 246 247 snprintf(buf, sizeof(buf), 248 "error:\tktrace() system call not supported in the running kernel\n\tre-compile kernel with 'option KTRACE'\n"); 249 write(STDERR_FILENO, buf, strlen(buf)); 250 _exit(1); 251 } 252