1 /*- 2 * Copyright 1997 Sean Eric Fagan 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. All advertising materials mentioning features or use of this software 13 * must display the following acknowledgement: 14 * This product includes software developed by Sean Eric Fagan 15 * 4. Neither the name of the author may be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 /* 36 * The main module for truss. Surprisingly simple, but, then, the other 37 * files handle the bulk of the work. And, of course, the kernel has to 38 * do a lot of the work :). 39 */ 40 41 #include <sys/param.h> 42 #include <sys/types.h> 43 #include <sys/time.h> 44 #include <sys/resource.h> 45 #include <sys/sysctl.h> 46 #include <sys/wait.h> 47 48 #include <err.h> 49 #include <errno.h> 50 #include <fcntl.h> 51 #include <signal.h> 52 #include <stdio.h> 53 #include <stdlib.h> 54 #include <string.h> 55 #include <time.h> 56 #include <unistd.h> 57 58 #include "truss.h" 59 #include "extern.h" 60 #include "syscall.h" 61 62 #define MAXARGS 6 63 64 static void 65 usage(void) 66 { 67 fprintf(stderr, "%s\n%s\n", 68 "usage: truss [-cfaedDS] [-o file] [-s strsize] -p pid", 69 " truss [-cfaedDS] [-o file] [-s strsize] command [args]"); 70 exit(1); 71 } 72 73 /* 74 * WARNING! "FreeBSD a.out" must be first, or set_etype will not 75 * work correctly. 76 */ 77 static struct ex_types { 78 const char *type; 79 void (*enter_syscall)(struct trussinfo *, int); 80 long (*exit_syscall)(struct trussinfo *, int); 81 } ex_types[] = { 82 #ifdef __amd64__ 83 { "FreeBSD ELF64", amd64_syscall_entry, amd64_syscall_exit }, 84 { "FreeBSD ELF32", amd64_fbsd32_syscall_entry, amd64_fbsd32_syscall_exit }, 85 { "Linux ELF32", amd64_linux32_syscall_entry, amd64_linux32_syscall_exit }, 86 #endif 87 #ifdef __i386__ 88 { "FreeBSD a.out", i386_syscall_entry, i386_syscall_exit }, 89 { "FreeBSD ELF", i386_syscall_entry, i386_syscall_exit }, 90 { "FreeBSD ELF32", i386_syscall_entry, i386_syscall_exit }, 91 { "Linux ELF", i386_linux_syscall_entry, i386_linux_syscall_exit }, 92 #endif 93 #ifdef __ia64__ 94 { "FreeBSD ELF64", ia64_syscall_entry, ia64_syscall_exit }, 95 #endif 96 #ifdef __powerpc__ 97 { "FreeBSD ELF", powerpc_syscall_entry, powerpc_syscall_exit }, 98 { "FreeBSD ELF32", powerpc_syscall_entry, powerpc_syscall_exit }, 99 #ifdef __powerpc64__ 100 { "FreeBSD ELF64", powerpc64_syscall_entry, powerpc64_syscall_exit }, 101 #endif 102 #endif 103 #ifdef __sparc64__ 104 { "FreeBSD ELF64", sparc64_syscall_entry, sparc64_syscall_exit }, 105 #endif 106 #ifdef __mips__ 107 { "FreeBSD ELF", mips_syscall_entry, mips_syscall_exit }, 108 { "FreeBSD ELF32", mips_syscall_entry, mips_syscall_exit }, 109 { "FreeBSD ELF64", mips_syscall_entry, mips_syscall_exit }, // XXX 110 #endif 111 { 0, 0, 0 }, 112 }; 113 114 /* 115 * Set the execution type. This is called after every exec, and when 116 * a process is first monitored. 117 */ 118 119 static struct ex_types * 120 set_etype(struct trussinfo *trussinfo) 121 { 122 struct ex_types *funcs; 123 size_t len; 124 int error; 125 int mib[4]; 126 char progt[32]; 127 128 len = sizeof(progt); 129 mib[0] = CTL_KERN; 130 mib[1] = KERN_PROC; 131 mib[2] = KERN_PROC_SV_NAME; 132 mib[3] = trussinfo->pid; 133 error = sysctl(mib, 4, progt, &len, NULL, 0); 134 if (error != 0) 135 err(2, "can not get etype"); 136 137 for (funcs = ex_types; funcs->type; funcs++) 138 if (strcmp(funcs->type, progt) == 0) 139 break; 140 141 if (funcs->type == NULL) { 142 funcs = &ex_types[0]; 143 warn("execution type %s is not supported -- using %s", 144 progt, funcs->type); 145 } 146 return (funcs); 147 } 148 149 char * 150 strsig(int sig) 151 { 152 char *ret; 153 154 ret = NULL; 155 if (sig > 0 && sig < NSIG) { 156 asprintf(&ret, "SIG%s", sys_signame[sig]); 157 if (ret == NULL) 158 return (NULL); 159 } 160 return (ret); 161 } 162 163 int 164 main(int ac, char **av) 165 { 166 struct ex_types *funcs; 167 struct trussinfo *trussinfo; 168 char *fname; 169 char *signame; 170 char **command; 171 pid_t childpid; 172 int c, i, initial_open, status; 173 174 fname = NULL; 175 initial_open = 1; 176 177 /* Initialize the trussinfo struct */ 178 trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo)); 179 if (trussinfo == NULL) 180 errx(1, "calloc() failed"); 181 182 trussinfo->outfile = stderr; 183 trussinfo->strsize = 32; 184 trussinfo->pr_why = S_NONE; 185 trussinfo->curthread = NULL; 186 SLIST_INIT(&trussinfo->threadlist); 187 while ((c = getopt(ac, av, "p:o:facedDs:S")) != -1) { 188 switch (c) { 189 case 'p': /* specified pid */ 190 trussinfo->pid = atoi(optarg); 191 /* make sure i don't trace me */ 192 if (trussinfo->pid == getpid()) { 193 fprintf(stderr, "attempt to grab self.\n"); 194 exit(2); 195 } 196 break; 197 case 'f': /* Follow fork()'s */ 198 trussinfo->flags |= FOLLOWFORKS; 199 break; 200 case 'a': /* Print execve() argument strings. */ 201 trussinfo->flags |= EXECVEARGS; 202 break; 203 case 'c': /* Count number of system calls and time. */ 204 trussinfo->flags |= COUNTONLY; 205 break; 206 case 'e': /* Print execve() environment strings. */ 207 trussinfo->flags |= EXECVEENVS; 208 break; 209 case 'd': /* Absolute timestamps */ 210 trussinfo->flags |= ABSOLUTETIMESTAMPS; 211 break; 212 case 'D': /* Relative timestamps */ 213 trussinfo->flags |= RELATIVETIMESTAMPS; 214 break; 215 case 'o': /* Specified output file */ 216 fname = optarg; 217 break; 218 case 's': /* Specified string size */ 219 trussinfo->strsize = atoi(optarg); 220 break; 221 case 'S': /* Don't trace signals */ 222 trussinfo->flags |= NOSIGS; 223 break; 224 default: 225 usage(); 226 } 227 } 228 229 ac -= optind; av += optind; 230 if ((trussinfo->pid == 0 && ac == 0) || 231 (trussinfo->pid != 0 && ac != 0)) 232 usage(); 233 234 if (fname != NULL) { /* Use output file */ 235 if ((trussinfo->outfile = fopen(fname, "w")) == NULL) 236 errx(1, "cannot open %s", fname); 237 /* 238 * Set FD_CLOEXEC, so that the output file is not shared with 239 * the traced process. 240 */ 241 if (fcntl(fileno(trussinfo->outfile), F_SETFD, FD_CLOEXEC) == 242 -1) 243 warn("fcntl()"); 244 } 245 246 /* 247 * If truss starts the process itself, it will ignore some signals -- 248 * they should be passed off to the process, which may or may not 249 * exit. If, however, we are examining an already-running process, 250 * then we restore the event mask on these same signals. 251 */ 252 253 if (trussinfo->pid == 0) { /* Start a command ourselves */ 254 command = av; 255 trussinfo->pid = setup_and_wait(command); 256 signal(SIGINT, SIG_IGN); 257 signal(SIGTERM, SIG_IGN); 258 signal(SIGQUIT, SIG_IGN); 259 } else { 260 start_tracing(trussinfo->pid); 261 signal(SIGINT, restore_proc); 262 signal(SIGTERM, restore_proc); 263 signal(SIGQUIT, restore_proc); 264 } 265 266 267 /* 268 * At this point, if we started the process, it is stopped waiting to 269 * be woken up, either in exit() or in execve(). 270 */ 271 272 START_TRACE: 273 funcs = set_etype(trussinfo); 274 275 initial_open = 0; 276 /* 277 * At this point, it's a simple loop, waiting for the process to 278 * stop, finding out why, printing out why, and then continuing it. 279 * All of the grunt work is done in the support routines. 280 */ 281 282 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 283 284 do { 285 struct timespec timediff; 286 waitevent(trussinfo); 287 288 switch (i = trussinfo->pr_why) { 289 case S_SCE: 290 funcs->enter_syscall(trussinfo, MAXARGS); 291 clock_gettime(CLOCK_REALTIME, 292 &trussinfo->before); 293 break; 294 case S_SCX: 295 clock_gettime(CLOCK_REALTIME, 296 &trussinfo->after); 297 298 if (trussinfo->curthread->in_fork && 299 (trussinfo->flags & FOLLOWFORKS)) { 300 trussinfo->curthread->in_fork = 0; 301 childpid = funcs->exit_syscall(trussinfo, 302 trussinfo->pr_data); 303 304 /* 305 * Fork a new copy of ourself to trace 306 * the child of the original traced 307 * process. 308 */ 309 if (fork() == 0) { 310 trussinfo->pid = childpid; 311 start_tracing(trussinfo->pid); 312 goto START_TRACE; 313 } 314 break; 315 } 316 funcs->exit_syscall(trussinfo, MAXARGS); 317 break; 318 case S_SIG: 319 if (trussinfo->flags & NOSIGS) 320 break; 321 if (trussinfo->flags & FOLLOWFORKS) 322 fprintf(trussinfo->outfile, "%5d: ", 323 trussinfo->pid); 324 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 325 timespecsubt(&trussinfo->after, 326 &trussinfo->start_time, &timediff); 327 fprintf(trussinfo->outfile, "%ld.%09ld ", 328 (long)timediff.tv_sec, 329 timediff.tv_nsec); 330 } 331 if (trussinfo->flags & RELATIVETIMESTAMPS) { 332 timespecsubt(&trussinfo->after, 333 &trussinfo->before, &timediff); 334 fprintf(trussinfo->outfile, "%ld.%09ld ", 335 (long)timediff.tv_sec, 336 timediff.tv_nsec); 337 } 338 signame = strsig(trussinfo->pr_data); 339 fprintf(trussinfo->outfile, 340 "SIGNAL %u (%s)\n", trussinfo->pr_data, 341 signame == NULL ? "?" : signame); 342 free(signame); 343 break; 344 case S_EXIT: 345 if (trussinfo->flags & COUNTONLY) 346 break; 347 if (trussinfo->flags & FOLLOWFORKS) 348 fprintf(trussinfo->outfile, "%5d: ", 349 trussinfo->pid); 350 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 351 timespecsubt(&trussinfo->after, 352 &trussinfo->start_time, &timediff); 353 fprintf(trussinfo->outfile, "%ld.%09ld ", 354 (long)timediff.tv_sec, 355 timediff.tv_nsec); 356 } 357 if (trussinfo->flags & RELATIVETIMESTAMPS) { 358 timespecsubt(&trussinfo->after, 359 &trussinfo->before, &timediff); 360 fprintf(trussinfo->outfile, "%ld.%09ld ", 361 (long)timediff.tv_sec, timediff.tv_nsec); 362 } 363 fprintf(trussinfo->outfile, 364 "process exit, rval = %u\n", trussinfo->pr_data); 365 break; 366 default: 367 break; 368 } 369 } while (trussinfo->pr_why != S_EXIT); 370 371 if (trussinfo->flags & FOLLOWFORKS) { 372 do { 373 childpid = wait(&status); 374 } while (childpid != -1); 375 } 376 377 if (trussinfo->flags & COUNTONLY) 378 print_summary(trussinfo); 379 380 fflush(trussinfo->outfile); 381 382 return (0); 383 } 384