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 __alpha__ 82 { "FreeBSD ELF", alpha_syscall_entry, alpha_syscall_exit }, 83 #endif 84 #ifdef __amd64__ 85 { "FreeBSD ELF64", amd64_syscall_entry, amd64_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 #endif 100 #ifdef __sparc64__ 101 { "FreeBSD ELF64", sparc64_syscall_entry, sparc64_syscall_exit }, 102 #endif 103 { 0, 0, 0 }, 104 }; 105 106 /* 107 * Set the execution type. This is called after every exec, and when 108 * a process is first monitored. 109 */ 110 111 static struct ex_types * 112 set_etype(struct trussinfo *trussinfo) 113 { 114 struct ex_types *funcs; 115 char progt[32]; 116 117 size_t len = sizeof(progt); 118 int mib[4]; 119 int error; 120 121 mib[0] = CTL_KERN; 122 mib[1] = KERN_PROC; 123 mib[2] = KERN_PROC_SV_NAME; 124 mib[3] = trussinfo->pid; 125 error = sysctl(mib, 4, progt, &len, NULL, 0); 126 if (error != 0) 127 err(2, "can not get etype"); 128 129 for (funcs = ex_types; funcs->type; funcs++) 130 if (!strcmp(funcs->type, progt)) 131 break; 132 133 if (funcs->type == NULL) { 134 funcs = &ex_types[0]; 135 warn("execution type %s is not supported -- using %s", 136 progt, funcs->type); 137 } 138 return (funcs); 139 } 140 141 char * 142 strsig(int sig) 143 { 144 char *ret; 145 146 ret = NULL; 147 if (sig > 0 && sig < NSIG) { 148 int i; 149 asprintf(&ret, "sig%s", sys_signame[sig]); 150 if (ret == NULL) 151 return (NULL); 152 for (i = 0; ret[i] != '\0'; ++i) 153 ret[i] = toupper(ret[i]); 154 } 155 return (ret); 156 } 157 158 int 159 main(int ac, char **av) 160 { 161 int c; 162 int i; 163 char **command; 164 struct ex_types *funcs; 165 int initial_open; 166 char *fname; 167 struct trussinfo *trussinfo; 168 char *signame; 169 170 fname = NULL; 171 initial_open = 1; 172 173 /* Initialize the trussinfo struct */ 174 trussinfo = (struct trussinfo *)malloc(sizeof(struct trussinfo)); 175 if (trussinfo == NULL) 176 errx(1, "malloc() failed"); 177 bzero(trussinfo, sizeof(struct trussinfo)); 178 179 trussinfo->outfile = stderr; 180 trussinfo->strsize = 32; 181 trussinfo->pr_why = S_NONE; 182 trussinfo->curthread = NULL; 183 SLIST_INIT(&trussinfo->threadlist); 184 while ((c = getopt(ac, av, "p:o:faedDs:S")) != -1) { 185 switch (c) { 186 case 'p': /* specified pid */ 187 trussinfo->pid = atoi(optarg); 188 /* make sure i don't trace me */ 189 if(trussinfo->pid == getpid()) { 190 fprintf(stderr, "attempt to grab self.\n"); 191 exit(2); 192 } 193 break; 194 case 'f': /* Follow fork()'s */ 195 trussinfo->flags |= FOLLOWFORKS; 196 break; 197 case 'a': /* Print execve() argument strings. */ 198 trussinfo->flags |= EXECVEARGS; 199 break; 200 case 'e': /* Print execve() environment strings. */ 201 trussinfo->flags |= EXECVEENVS; 202 break; 203 case 'd': /* Absolute timestamps */ 204 trussinfo->flags |= ABSOLUTETIMESTAMPS; 205 break; 206 case 'D': /* Relative timestamps */ 207 trussinfo->flags |= RELATIVETIMESTAMPS; 208 break; 209 case 'o': /* Specified output file */ 210 fname = optarg; 211 break; 212 case 's': /* Specified string size */ 213 trussinfo->strsize = atoi(optarg); 214 break; 215 case 'S': /* Don't trace signals */ 216 trussinfo->flags |= NOSIGS; 217 break; 218 default: 219 usage(); 220 } 221 } 222 223 ac -= optind; av += optind; 224 if ((trussinfo->pid == 0 && ac == 0) || 225 (trussinfo->pid != 0 && ac != 0)) 226 usage(); 227 228 if (fname != NULL) { /* Use output file */ 229 if ((trussinfo->outfile = fopen(fname, "w")) == NULL) 230 errx(1, "cannot open %s", fname); 231 } 232 233 /* 234 * If truss starts the process itself, it will ignore some signals -- 235 * they should be passed off to the process, which may or may not 236 * exit. If, however, we are examining an already-running process, 237 * then we restore the event mask on these same signals. 238 */ 239 240 if (trussinfo->pid == 0) { /* Start a command ourselves */ 241 command = av; 242 trussinfo->pid = setup_and_wait(command); 243 signal(SIGINT, SIG_IGN); 244 signal(SIGTERM, SIG_IGN); 245 signal(SIGQUIT, SIG_IGN); 246 } else { 247 start_tracing(trussinfo->pid); 248 signal(SIGINT, restore_proc); 249 signal(SIGTERM, restore_proc); 250 signal(SIGQUIT, restore_proc); 251 } 252 253 254 /* 255 * At this point, if we started the process, it is stopped waiting to 256 * be woken up, either in exit() or in execve(). 257 */ 258 259 START_TRACE: 260 funcs = set_etype(trussinfo); 261 262 initial_open = 0; 263 /* 264 * At this point, it's a simple loop, waiting for the process to 265 * stop, finding out why, printing out why, and then continuing it. 266 * All of the grunt work is done in the support routines. 267 */ 268 269 clock_gettime(CLOCK_REALTIME, &trussinfo->start_time); 270 271 do { 272 struct timespec timediff; 273 waitevent(trussinfo); 274 275 switch(i = trussinfo->pr_why) { 276 case S_SCE: 277 funcs->enter_syscall(trussinfo, MAXARGS); 278 clock_gettime(CLOCK_REALTIME, 279 &trussinfo->before); 280 break; 281 case S_SCX: 282 clock_gettime(CLOCK_REALTIME, 283 &trussinfo->after); 284 285 if (trussinfo->curthread->in_fork && 286 (trussinfo->flags & FOLLOWFORKS)) { 287 int childpid; 288 289 trussinfo->curthread->in_fork = 0; 290 childpid = 291 funcs->exit_syscall(trussinfo, 292 trussinfo->pr_data); 293 294 /* 295 * Fork a new copy of ourself to trace 296 * the child of the original traced 297 * process. 298 */ 299 if (fork() == 0) { 300 trussinfo->pid = childpid; 301 start_tracing(trussinfo->pid); 302 goto START_TRACE; 303 } 304 break; 305 } 306 funcs->exit_syscall(trussinfo, MAXARGS); 307 break; 308 case S_SIG: 309 if (trussinfo->flags & NOSIGS) 310 break; 311 if (trussinfo->flags & FOLLOWFORKS) 312 fprintf(trussinfo->outfile, "%5d: ", 313 trussinfo->pid); 314 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 315 timespecsubt(&trussinfo->after, 316 &trussinfo->start_time, &timediff); 317 fprintf(trussinfo->outfile, "%ld.%09ld ", 318 (long)timediff.tv_sec, 319 timediff.tv_nsec); 320 } 321 if (trussinfo->flags & RELATIVETIMESTAMPS) { 322 timespecsubt(&trussinfo->after, 323 &trussinfo->before, &timediff); 324 fprintf(trussinfo->outfile, "%ld.%09ld ", 325 (long)timediff.tv_sec, 326 timediff.tv_nsec); 327 } 328 signame = strsig(trussinfo->pr_data); 329 fprintf(trussinfo->outfile, 330 "SIGNAL %u (%s)\n", trussinfo->pr_data, 331 signame == NULL ? "?" : signame); 332 free(signame); 333 break; 334 case S_EXIT: 335 if (trussinfo->flags & FOLLOWFORKS) 336 fprintf(trussinfo->outfile, "%5d: ", 337 trussinfo->pid); 338 if (trussinfo->flags & ABSOLUTETIMESTAMPS) { 339 timespecsubt(&trussinfo->after, 340 &trussinfo->start_time, &timediff); 341 fprintf(trussinfo->outfile, "%ld.%09ld ", 342 (long)timediff.tv_sec, 343 timediff.tv_nsec); 344 } 345 if (trussinfo->flags & RELATIVETIMESTAMPS) { 346 timespecsubt(&trussinfo->after, 347 &trussinfo->before, &timediff); 348 fprintf(trussinfo->outfile, "%ld.%09ld ", 349 (long)timediff.tv_sec, timediff.tv_nsec); 350 } 351 fprintf(trussinfo->outfile, 352 "process exit, rval = %u\n", trussinfo->pr_data); 353 break; 354 default: 355 break; 356 } 357 } while (trussinfo->pr_why != S_EXIT); 358 fflush(trussinfo->outfile); 359 360 return (0); 361 } 362