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 <ctype.h> 49 #include <err.h> 50 #include <errno.h> 51 #include <fcntl.h> 52 #include <signal.h> 53 #include <stdio.h> 54 #include <stdlib.h> 55 #include <string.h> 56 #include <time.h> 57 #include <unistd.h> 58 59 #include "truss.h" 60 #include "extern.h" 61 #include "syscall.h" 62 63 #define MAXARGS 6 64 65 static void 66 usage(void) 67 { 68 fprintf(stderr, "%s\n%s\n", 69 "usage: truss [-cfaedDS] [-o file] [-s strsize] -p pid", 70 " truss [-cfaedDS] [-o file] [-s strsize] command [args]"); 71 exit(1); 72 } 73 74 /* 75 * WARNING! "FreeBSD a.out" must be first, or set_etype will not 76 * work correctly. 77 */ 78 struct ex_types { 79 const char *type; 80 void (*enter_syscall)(struct trussinfo *, int); 81 long (*exit_syscall)(struct trussinfo *, int); 82 } ex_types[] = { 83 #ifdef __amd64__ 84 { "FreeBSD ELF64", amd64_syscall_entry, amd64_syscall_exit }, 85 { "FreeBSD ELF32", amd64_fbsd32_syscall_entry, amd64_fbsd32_syscall_exit }, 86 { "Linux ELF32", amd64_linux32_syscall_entry, amd64_linux32_syscall_exit }, 87 #endif 88 #ifdef __i386__ 89 { "FreeBSD a.out", i386_syscall_entry, i386_syscall_exit }, 90 { "FreeBSD ELF", i386_syscall_entry, i386_syscall_exit }, 91 { "FreeBSD ELF32", i386_syscall_entry, i386_syscall_exit }, 92 { "Linux ELF", i386_linux_syscall_entry, i386_linux_syscall_exit }, 93 #endif 94 #ifdef __ia64__ 95 { "FreeBSD ELF64", ia64_syscall_entry, ia64_syscall_exit }, 96 #endif 97 #ifdef __powerpc__ 98 { "FreeBSD ELF", powerpc_syscall_entry, powerpc_syscall_exit }, 99 { "FreeBSD ELF32", powerpc_syscall_entry, powerpc_syscall_exit }, 100 #ifdef __powerpc64__ 101 { "FreeBSD ELF64", powerpc64_syscall_entry, powerpc64_syscall_exit }, 102 #endif 103 #endif 104 #ifdef __sparc64__ 105 { "FreeBSD ELF64", sparc64_syscall_entry, sparc64_syscall_exit }, 106 #endif 107 #ifdef __mips__ 108 { "FreeBSD ELF", mips_syscall_entry, mips_syscall_exit }, 109 { "FreeBSD ELF32", mips_syscall_entry, mips_syscall_exit }, 110 { "FreeBSD ELF64", mips_syscall_entry, mips_syscall_exit }, // XXX 111 #endif 112 { 0, 0, 0 }, 113 }; 114 115 /* 116 * Set the execution type. This is called after every exec, and when 117 * a process is first monitored. 118 */ 119 120 static struct ex_types * 121 set_etype(struct trussinfo *trussinfo) 122 { 123 struct ex_types *funcs; 124 char progt[32]; 125 126 size_t len = sizeof(progt); 127 int mib[4]; 128 int error; 129 130 mib[0] = CTL_KERN; 131 mib[1] = KERN_PROC; 132 mib[2] = KERN_PROC_SV_NAME; 133 mib[3] = trussinfo->pid; 134 error = sysctl(mib, 4, progt, &len, NULL, 0); 135 if (error != 0) 136 err(2, "can not get etype"); 137 138 for (funcs = ex_types; funcs->type; funcs++) 139 if (!strcmp(funcs->type, progt)) 140 break; 141 142 if (funcs->type == NULL) { 143 funcs = &ex_types[0]; 144 warn("execution type %s is not supported -- using %s", 145 progt, funcs->type); 146 } 147 return (funcs); 148 } 149 150 char * 151 strsig(int sig) 152 { 153 char *ret; 154 155 ret = NULL; 156 if (sig > 0 && sig < NSIG) { 157 int i; 158 asprintf(&ret, "SIG%s", sys_signame[sig]); 159 if (ret == NULL) 160 return (NULL); 161 for (i = 0; ret[i] != '\0'; ++i) 162 ret[i] = toupper(ret[i]); 163 } 164 return (ret); 165 } 166 167 int 168 main(int ac, char **av) 169 { 170 int c; 171 int i; 172 pid_t childpid; 173 int status; 174 char **command; 175 struct ex_types *funcs; 176 int initial_open; 177 char *fname; 178 struct trussinfo *trussinfo; 179 char *signame; 180 181 fname = NULL; 182 initial_open = 1; 183 184 /* Initialize the trussinfo struct */ 185 trussinfo = (struct trussinfo *)calloc(1, sizeof(struct trussinfo)); 186 if (trussinfo == NULL) 187 errx(1, "calloc() failed"); 188 189 trussinfo->outfile = stderr; 190 trussinfo->strsize = 32; 191 trussinfo->pr_why = S_NONE; 192 trussinfo->curthread = NULL; 193 SLIST_INIT(&trussinfo->threadlist); 194 while ((c = getopt(ac, av, "p:o:facedDs:S")) != -1) { 195 switch (c) { 196 case 'p': /* specified pid */ 197 trussinfo->pid = atoi(optarg); 198 /* make sure i don't trace me */ 199 if(trussinfo->pid == getpid()) { 200 fprintf(stderr, "attempt to grab self.\n"); 201 exit(2); 202 } 203 break; 204 case 'f': /* Follow fork()'s */ 205 trussinfo->flags |= FOLLOWFORKS; 206 break; 207 case 'a': /* Print execve() argument strings. */ 208 trussinfo->flags |= EXECVEARGS; 209 break; 210 case 'c': /* Count number of system calls and time. */ 211 trussinfo->flags |= COUNTONLY; 212 break; 213 case 'e': /* Print execve() environment strings. */ 214 trussinfo->flags |= EXECVEENVS; 215 break; 216 case 'd': /* Absolute timestamps */ 217 trussinfo->flags |= ABSOLUTETIMESTAMPS; 218 break; 219 case 'D': /* Relative timestamps */ 220 trussinfo->flags |= RELATIVETIMESTAMPS; 221 break; 222 case 'o': /* Specified output file */ 223 fname = optarg; 224 break; 225 case 's': /* Specified string size */ 226 trussinfo->strsize = atoi(optarg); 227 break; 228 case 'S': /* Don't trace signals */ 229 trussinfo->flags |= NOSIGS; 230 break; 231 default: 232 usage(); 233 } 234 } 235 236 ac -= optind; av += optind; 237 if ((trussinfo->pid == 0 && ac == 0) || 238 (trussinfo->pid != 0 && ac != 0)) 239 usage(); 240 241 if (fname != NULL) { /* Use output file */ 242 if ((trussinfo->outfile = fopen(fname, "w")) == NULL) 243 errx(1, "cannot open %s", fname); 244 /* 245 * Set FD_CLOEXEC, so that the output file is not shared with 246 * the traced process. 247 */ 248 if (fcntl(fileno(trussinfo->outfile), F_SETFD, FD_CLOEXEC) == 249 -1) 250 warn("fcntl()"); 251 } 252 253 /* 254 * If truss starts the process itself, it will ignore some signals -- 255 * they should be passed off to the process, which may or may not 256 * exit. If, however, we are examining an already-running process, 257 * then we restore the event mask on these same signals. 258 */ 259 260 if (trussinfo->pid == 0) { /* Start a command ourselves */ 261 command = av; 262 trussinfo->pid = setup_and_wait(command); 263 signal(SIGINT, SIG_IGN); 264 signal(SIGTERM, SIG_IGN); 265 signal(SIGQUIT, SIG_IGN); 266 } else { 267 start_tracing(trussinfo->pid); 268 signal(SIGINT, restore_proc); 269 signal(SIGTERM, restore_proc); 270 signal(SIGQUIT, restore_proc); 271 } 272 273 274 /* 275 * At this point, if we started the process, it is stopped waiting to 276 * be woken up, either in exit() or in execve(). 277 */ 278 279 START_TRACE: 280 funcs = set_etype(trussinfo); 281 282 initial_open = 0; 283 /* 284 * At this point, it's a simple loop, waiting for the process to 285 * stop, finding out why, printing out why, and then continuing it. 286 * All of the grunt work is done in the support routines. 287 */ 288 289 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 290 291 do { 292 struct timespec timediff; 293 waitevent(trussinfo); 294 295 switch(i = trussinfo->pr_why) { 296 case S_SCE: 297 funcs->enter_syscall(trussinfo, MAXARGS); 298 clock_gettime(CLOCK_REALTIME, 299 &trussinfo->before); 300 break; 301 case S_SCX: 302 clock_gettime(CLOCK_REALTIME, 303 &trussinfo->after); 304 305 if (trussinfo->curthread->in_fork && 306 (trussinfo->flags & FOLLOWFORKS)) { 307 trussinfo->curthread->in_fork = 0; 308 childpid = 309 funcs->exit_syscall(trussinfo, 310 trussinfo->pr_data); 311 312 /* 313 * Fork a new copy of ourself to trace 314 * the child of the original traced 315 * process. 316 */ 317 if (fork() == 0) { 318 trussinfo->pid = childpid; 319 start_tracing(trussinfo->pid); 320 goto START_TRACE; 321 } 322 break; 323 } 324 funcs->exit_syscall(trussinfo, MAXARGS); 325 break; 326 case S_SIG: 327 if (trussinfo->flags & NOSIGS) 328 break; 329 if (trussinfo->flags & FOLLOWFORKS) 330 fprintf(trussinfo->outfile, "%5d: ", 331 trussinfo->pid); 332 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 333 timespecsubt(&trussinfo->after, 334 &trussinfo->start_time, &timediff); 335 fprintf(trussinfo->outfile, "%ld.%09ld ", 336 (long)timediff.tv_sec, 337 timediff.tv_nsec); 338 } 339 if (trussinfo->flags & RELATIVETIMESTAMPS) { 340 timespecsubt(&trussinfo->after, 341 &trussinfo->before, &timediff); 342 fprintf(trussinfo->outfile, "%ld.%09ld ", 343 (long)timediff.tv_sec, 344 timediff.tv_nsec); 345 } 346 signame = strsig(trussinfo->pr_data); 347 fprintf(trussinfo->outfile, 348 "SIGNAL %u (%s)\n", trussinfo->pr_data, 349 signame == NULL ? "?" : signame); 350 free(signame); 351 break; 352 case S_EXIT: 353 if (trussinfo->flags & COUNTONLY) 354 break; 355 if (trussinfo->flags & FOLLOWFORKS) 356 fprintf(trussinfo->outfile, "%5d: ", 357 trussinfo->pid); 358 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 359 timespecsubt(&trussinfo->after, 360 &trussinfo->start_time, &timediff); 361 fprintf(trussinfo->outfile, "%ld.%09ld ", 362 (long)timediff.tv_sec, 363 timediff.tv_nsec); 364 } 365 if (trussinfo->flags & RELATIVETIMESTAMPS) { 366 timespecsubt(&trussinfo->after, 367 &trussinfo->before, &timediff); 368 fprintf(trussinfo->outfile, "%ld.%09ld ", 369 (long)timediff.tv_sec, timediff.tv_nsec); 370 } 371 fprintf(trussinfo->outfile, 372 "process exit, rval = %u\n", trussinfo->pr_data); 373 break; 374 default: 375 break; 376 } 377 } while (trussinfo->pr_why != S_EXIT); 378 379 if (trussinfo->flags & FOLLOWFORKS) 380 do { 381 childpid = wait(&status); 382 } while (childpid != -1); 383 384 if (trussinfo->flags & COUNTONLY) 385 print_summary(trussinfo); 386 387 fflush(trussinfo->outfile); 388 389 return (0); 390 } 391