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. Suprisingly 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 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 char progt[32]; 124 125 size_t len = sizeof(progt); 126 int mib[4]; 127 int error; 128 129 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)) 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 int c; 167 int i; 168 pid_t childpid; 169 int status; 170 char **command; 171 struct ex_types *funcs; 172 int initial_open; 173 char *fname; 174 struct trussinfo *trussinfo; 175 char *signame; 176 177 fname = NULL; 178 initial_open = 1; 179 180 /* Initialize the trussinfo struct */ 181 trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo)); 182 if (trussinfo == NULL) 183 errx(1, "calloc() failed"); 184 185 trussinfo->outfile = stderr; 186 trussinfo->strsize = 32; 187 trussinfo->pr_why = S_NONE; 188 trussinfo->curthread = NULL; 189 SLIST_INIT(&trussinfo->threadlist); 190 while ((c = getopt(ac, av, "p:o:facedDs:S")) != -1) { 191 switch (c) { 192 case 'p': /* specified pid */ 193 trussinfo->pid = atoi(optarg); 194 /* make sure i don't trace me */ 195 if(trussinfo->pid == getpid()) { 196 fprintf(stderr, "attempt to grab self.\n"); 197 exit(2); 198 } 199 break; 200 case 'f': /* Follow fork()'s */ 201 trussinfo->flags |= FOLLOWFORKS; 202 break; 203 case 'a': /* Print execve() argument strings. */ 204 trussinfo->flags |= EXECVEARGS; 205 break; 206 case 'c': /* Count number of system calls and time. */ 207 trussinfo->flags |= COUNTONLY; 208 break; 209 case 'e': /* Print execve() environment strings. */ 210 trussinfo->flags |= EXECVEENVS; 211 break; 212 case 'd': /* Absolute timestamps */ 213 trussinfo->flags |= ABSOLUTETIMESTAMPS; 214 break; 215 case 'D': /* Relative timestamps */ 216 trussinfo->flags |= RELATIVETIMESTAMPS; 217 break; 218 case 'o': /* Specified output file */ 219 fname = optarg; 220 break; 221 case 's': /* Specified string size */ 222 trussinfo->strsize = atoi(optarg); 223 break; 224 case 'S': /* Don't trace signals */ 225 trussinfo->flags |= NOSIGS; 226 break; 227 default: 228 usage(); 229 } 230 } 231 232 ac -= optind; av += optind; 233 if ((trussinfo->pid == 0 && ac == 0) || 234 (trussinfo->pid != 0 && ac != 0)) 235 usage(); 236 237 if (fname != NULL) { /* Use output file */ 238 if ((trussinfo->outfile = fopen(fname, "w")) == NULL) 239 errx(1, "cannot open %s", fname); 240 /* 241 * Set FD_CLOEXEC, so that the output file is not shared with 242 * the traced process. 243 */ 244 if (fcntl(fileno(trussinfo->outfile), F_SETFD, FD_CLOEXEC) == 245 -1) 246 warn("fcntl()"); 247 } 248 249 /* 250 * If truss starts the process itself, it will ignore some signals -- 251 * they should be passed off to the process, which may or may not 252 * exit. If, however, we are examining an already-running process, 253 * then we restore the event mask on these same signals. 254 */ 255 256 if (trussinfo->pid == 0) { /* Start a command ourselves */ 257 command = av; 258 trussinfo->pid = setup_and_wait(command); 259 signal(SIGINT, SIG_IGN); 260 signal(SIGTERM, SIG_IGN); 261 signal(SIGQUIT, SIG_IGN); 262 } else { 263 start_tracing(trussinfo->pid); 264 signal(SIGINT, restore_proc); 265 signal(SIGTERM, restore_proc); 266 signal(SIGQUIT, restore_proc); 267 } 268 269 270 /* 271 * At this point, if we started the process, it is stopped waiting to 272 * be woken up, either in exit() or in execve(). 273 */ 274 275 START_TRACE: 276 funcs = set_etype(trussinfo); 277 278 initial_open = 0; 279 /* 280 * At this point, it's a simple loop, waiting for the process to 281 * stop, finding out why, printing out why, and then continuing it. 282 * All of the grunt work is done in the support routines. 283 */ 284 285 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 286 287 do { 288 struct timespec timediff; 289 waitevent(trussinfo); 290 291 switch(i = trussinfo->pr_why) { 292 case S_SCE: 293 funcs->enter_syscall(trussinfo, MAXARGS); 294 clock_gettime(CLOCK_REALTIME, 295 &trussinfo->before); 296 break; 297 case S_SCX: 298 clock_gettime(CLOCK_REALTIME, 299 &trussinfo->after); 300 301 if (trussinfo->curthread->in_fork && 302 (trussinfo->flags & FOLLOWFORKS)) { 303 trussinfo->curthread->in_fork = 0; 304 childpid = 305 funcs->exit_syscall(trussinfo, 306 trussinfo->pr_data); 307 308 /* 309 * Fork a new copy of ourself to trace 310 * the child of the original traced 311 * process. 312 */ 313 if (fork() == 0) { 314 trussinfo->pid = childpid; 315 start_tracing(trussinfo->pid); 316 goto START_TRACE; 317 } 318 break; 319 } 320 funcs->exit_syscall(trussinfo, MAXARGS); 321 break; 322 case S_SIG: 323 if (trussinfo->flags & NOSIGS) 324 break; 325 if (trussinfo->flags & FOLLOWFORKS) 326 fprintf(trussinfo->outfile, "%5d: ", 327 trussinfo->pid); 328 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 329 timespecsubt(&trussinfo->after, 330 &trussinfo->start_time, &timediff); 331 fprintf(trussinfo->outfile, "%ld.%09ld ", 332 (long)timediff.tv_sec, 333 timediff.tv_nsec); 334 } 335 if (trussinfo->flags & RELATIVETIMESTAMPS) { 336 timespecsubt(&trussinfo->after, 337 &trussinfo->before, &timediff); 338 fprintf(trussinfo->outfile, "%ld.%09ld ", 339 (long)timediff.tv_sec, 340 timediff.tv_nsec); 341 } 342 signame = strsig(trussinfo->pr_data); 343 fprintf(trussinfo->outfile, 344 "SIGNAL %u (%s)\n", trussinfo->pr_data, 345 signame == NULL ? "?" : signame); 346 free(signame); 347 break; 348 case S_EXIT: 349 if (trussinfo->flags & COUNTONLY) 350 break; 351 if (trussinfo->flags & FOLLOWFORKS) 352 fprintf(trussinfo->outfile, "%5d: ", 353 trussinfo->pid); 354 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 355 timespecsubt(&trussinfo->after, 356 &trussinfo->start_time, &timediff); 357 fprintf(trussinfo->outfile, "%ld.%09ld ", 358 (long)timediff.tv_sec, 359 timediff.tv_nsec); 360 } 361 if (trussinfo->flags & RELATIVETIMESTAMPS) { 362 timespecsubt(&trussinfo->after, 363 &trussinfo->before, &timediff); 364 fprintf(trussinfo->outfile, "%ld.%09ld ", 365 (long)timediff.tv_sec, timediff.tv_nsec); 366 } 367 fprintf(trussinfo->outfile, 368 "process exit, rval = %u\n", trussinfo->pr_data); 369 break; 370 default: 371 break; 372 } 373 } while (trussinfo->pr_why != S_EXIT); 374 375 if (trussinfo->flags & FOLLOWFORKS) 376 do { 377 childpid = wait(&status); 378 } while (childpid != -1); 379 380 if (trussinfo->flags & COUNTONLY) 381 print_summary(trussinfo); 382 383 fflush(trussinfo->outfile); 384 385 return (0); 386 } 387