1 /* 2 * Copryight 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 47 #include <ctype.h> 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 61 #define MAXARGS 6 62 63 static void 64 usage(void) 65 { 66 fprintf(stderr, "%s\n%s\n", 67 "usage: truss [-faedDS] [-o file] [-s strsize] -p pid", 68 " truss [-faedDS] [-o file] [-s strsize] command [args]"); 69 exit(1); 70 } 71 72 /* 73 * WARNING! "FreeBSD a.out" must be first, or set_etype will not 74 * work correctly. 75 */ 76 struct ex_types { 77 const char *type; 78 void (*enter_syscall)(struct trussinfo *, int); 79 long (*exit_syscall)(struct trussinfo *, int); 80 } ex_types[] = { 81 #ifdef __amd64__ 82 { "FreeBSD ELF64", amd64_syscall_entry, amd64_syscall_exit }, 83 { "FreeBSD ELF32", amd64_fbsd32_syscall_entry, amd64_fbsd32_syscall_exit }, 84 { "Linux ELF32", amd64_linux32_syscall_entry, amd64_linux32_syscall_exit }, 85 #endif 86 #ifdef __i386__ 87 { "FreeBSD a.out", i386_syscall_entry, i386_syscall_exit }, 88 { "FreeBSD ELF", i386_syscall_entry, i386_syscall_exit }, 89 { "FreeBSD ELF32", i386_syscall_entry, i386_syscall_exit }, 90 { "Linux ELF", i386_linux_syscall_entry, i386_linux_syscall_exit }, 91 #endif 92 #ifdef __ia64__ 93 { "FreeBSD ELF64", ia64_syscall_entry, ia64_syscall_exit }, 94 #endif 95 #ifdef __powerpc__ 96 { "FreeBSD ELF", powerpc_syscall_entry, powerpc_syscall_exit }, 97 { "FreeBSD ELF32", powerpc_syscall_entry, powerpc_syscall_exit }, 98 #endif 99 #ifdef __sparc64__ 100 { "FreeBSD ELF64", sparc64_syscall_entry, sparc64_syscall_exit }, 101 #endif 102 { 0, 0, 0 }, 103 }; 104 105 /* 106 * Set the execution type. This is called after every exec, and when 107 * a process is first monitored. 108 */ 109 110 static struct ex_types * 111 set_etype(struct trussinfo *trussinfo) 112 { 113 struct ex_types *funcs; 114 char progt[32]; 115 116 size_t len = sizeof(progt); 117 int mib[4]; 118 int error; 119 120 mib[0] = CTL_KERN; 121 mib[1] = KERN_PROC; 122 mib[2] = KERN_PROC_SV_NAME; 123 mib[3] = trussinfo->pid; 124 error = sysctl(mib, 4, progt, &len, NULL, 0); 125 if (error != 0) 126 err(2, "can not get etype"); 127 128 for (funcs = ex_types; funcs->type; funcs++) 129 if (!strcmp(funcs->type, progt)) 130 break; 131 132 if (funcs->type == NULL) { 133 funcs = &ex_types[0]; 134 warn("execution type %s is not supported -- using %s", 135 progt, funcs->type); 136 } 137 return (funcs); 138 } 139 140 char * 141 strsig(int sig) 142 { 143 char *ret; 144 145 ret = NULL; 146 if (sig > 0 && sig < NSIG) { 147 int i; 148 asprintf(&ret, "sig%s", sys_signame[sig]); 149 if (ret == NULL) 150 return (NULL); 151 for (i = 0; ret[i] != '\0'; ++i) 152 ret[i] = toupper(ret[i]); 153 } 154 return (ret); 155 } 156 157 int 158 main(int ac, char **av) 159 { 160 int c; 161 int i; 162 char **command; 163 struct ex_types *funcs; 164 int initial_open; 165 char *fname; 166 struct trussinfo *trussinfo; 167 char *signame; 168 169 fname = NULL; 170 initial_open = 1; 171 172 /* Initialize the trussinfo struct */ 173 trussinfo = (struct trussinfo *)malloc(sizeof(struct trussinfo)); 174 if (trussinfo == NULL) 175 errx(1, "malloc() failed"); 176 bzero(trussinfo, sizeof(struct trussinfo)); 177 178 trussinfo->outfile = stderr; 179 trussinfo->strsize = 32; 180 trussinfo->pr_why = S_NONE; 181 trussinfo->curthread = NULL; 182 SLIST_INIT(&trussinfo->threadlist); 183 while ((c = getopt(ac, av, "p:o:faedDs:S")) != -1) { 184 switch (c) { 185 case 'p': /* specified pid */ 186 trussinfo->pid = atoi(optarg); 187 /* make sure i don't trace me */ 188 if(trussinfo->pid == getpid()) { 189 fprintf(stderr, "attempt to grab self.\n"); 190 exit(2); 191 } 192 break; 193 case 'f': /* Follow fork()'s */ 194 trussinfo->flags |= FOLLOWFORKS; 195 break; 196 case 'a': /* Print execve() argument strings. */ 197 trussinfo->flags |= EXECVEARGS; 198 break; 199 case 'e': /* Print execve() environment strings. */ 200 trussinfo->flags |= EXECVEENVS; 201 break; 202 case 'd': /* Absolute timestamps */ 203 trussinfo->flags |= ABSOLUTETIMESTAMPS; 204 break; 205 case 'D': /* Relative timestamps */ 206 trussinfo->flags |= RELATIVETIMESTAMPS; 207 break; 208 case 'o': /* Specified output file */ 209 fname = optarg; 210 break; 211 case 's': /* Specified string size */ 212 trussinfo->strsize = atoi(optarg); 213 break; 214 case 'S': /* Don't trace signals */ 215 trussinfo->flags |= NOSIGS; 216 break; 217 default: 218 usage(); 219 } 220 } 221 222 ac -= optind; av += optind; 223 if ((trussinfo->pid == 0 && ac == 0) || 224 (trussinfo->pid != 0 && ac != 0)) 225 usage(); 226 227 if (fname != NULL) { /* Use output file */ 228 if ((trussinfo->outfile = fopen(fname, "w")) == NULL) 229 errx(1, "cannot open %s", fname); 230 } 231 232 /* 233 * If truss starts the process itself, it will ignore some signals -- 234 * they should be passed off to the process, which may or may not 235 * exit. If, however, we are examining an already-running process, 236 * then we restore the event mask on these same signals. 237 */ 238 239 if (trussinfo->pid == 0) { /* Start a command ourselves */ 240 command = av; 241 trussinfo->pid = setup_and_wait(command); 242 signal(SIGINT, SIG_IGN); 243 signal(SIGTERM, SIG_IGN); 244 signal(SIGQUIT, SIG_IGN); 245 } else { 246 start_tracing(trussinfo->pid); 247 signal(SIGINT, restore_proc); 248 signal(SIGTERM, restore_proc); 249 signal(SIGQUIT, restore_proc); 250 } 251 252 253 /* 254 * At this point, if we started the process, it is stopped waiting to 255 * be woken up, either in exit() or in execve(). 256 */ 257 258 START_TRACE: 259 funcs = set_etype(trussinfo); 260 261 initial_open = 0; 262 /* 263 * At this point, it's a simple loop, waiting for the process to 264 * stop, finding out why, printing out why, and then continuing it. 265 * All of the grunt work is done in the support routines. 266 */ 267 268 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 269 270 do { 271 struct timespec timediff; 272 waitevent(trussinfo); 273 274 switch(i = trussinfo->pr_why) { 275 case S_SCE: 276 funcs->enter_syscall(trussinfo, MAXARGS); 277 clock_gettime(CLOCK_REALTIME, 278 &trussinfo->before); 279 break; 280 case S_SCX: 281 clock_gettime(CLOCK_REALTIME, 282 &trussinfo->after); 283 284 if (trussinfo->curthread->in_fork && 285 (trussinfo->flags & FOLLOWFORKS)) { 286 int childpid; 287 288 trussinfo->curthread->in_fork = 0; 289 childpid = 290 funcs->exit_syscall(trussinfo, 291 trussinfo->pr_data); 292 293 /* 294 * Fork a new copy of ourself to trace 295 * the child of the original traced 296 * process. 297 */ 298 if (fork() == 0) { 299 trussinfo->pid = childpid; 300 start_tracing(trussinfo->pid); 301 goto START_TRACE; 302 } 303 break; 304 } 305 funcs->exit_syscall(trussinfo, MAXARGS); 306 break; 307 case S_SIG: 308 if (trussinfo->flags & NOSIGS) 309 break; 310 if (trussinfo->flags & FOLLOWFORKS) 311 fprintf(trussinfo->outfile, "%5d: ", 312 trussinfo->pid); 313 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 314 timespecsubt(&trussinfo->after, 315 &trussinfo->start_time, &timediff); 316 fprintf(trussinfo->outfile, "%ld.%09ld ", 317 (long)timediff.tv_sec, 318 timediff.tv_nsec); 319 } 320 if (trussinfo->flags & RELATIVETIMESTAMPS) { 321 timespecsubt(&trussinfo->after, 322 &trussinfo->before, &timediff); 323 fprintf(trussinfo->outfile, "%ld.%09ld ", 324 (long)timediff.tv_sec, 325 timediff.tv_nsec); 326 } 327 signame = strsig(trussinfo->pr_data); 328 fprintf(trussinfo->outfile, 329 "SIGNAL %u (%s)\n", trussinfo->pr_data, 330 signame == NULL ? "?" : signame); 331 free(signame); 332 break; 333 case S_EXIT: 334 if (trussinfo->flags & FOLLOWFORKS) 335 fprintf(trussinfo->outfile, "%5d: ", 336 trussinfo->pid); 337 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 338 timespecsubt(&trussinfo->after, 339 &trussinfo->start_time, &timediff); 340 fprintf(trussinfo->outfile, "%ld.%09ld ", 341 (long)timediff.tv_sec, 342 timediff.tv_nsec); 343 } 344 if (trussinfo->flags & RELATIVETIMESTAMPS) { 345 timespecsubt(&trussinfo->after, 346 &trussinfo->before, &timediff); 347 fprintf(trussinfo->outfile, "%ld.%09ld ", 348 (long)timediff.tv_sec, timediff.tv_nsec); 349 } 350 fprintf(trussinfo->outfile, 351 "process exit, rval = %u\n", trussinfo->pr_data); 352 break; 353 default: 354 break; 355 } 356 } while (trussinfo->pr_why != S_EXIT); 357 fflush(trussinfo->outfile); 358 359 return (0); 360 } 361