xref: /freebsd/usr.bin/truss/syscalls.c (revision 262e143bd46171a6415a5b28af260a5efa2a3db8)
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 #ifndef lint
33 static const char rcsid[] =
34   "$FreeBSD$";
35 #endif /* not lint */
36 
37 /*
38  * This file has routines used to print out system calls and their
39  * arguments.
40  */
41 
42 #include <sys/mman.h>
43 #include <sys/types.h>
44 #include <sys/socket.h>
45 #include <sys/time.h>
46 #include <sys/un.h>
47 #include <netinet/in.h>
48 #include <arpa/inet.h>
49 
50 #include <ctype.h>
51 #include <err.h>
52 #include <fcntl.h>
53 #include <poll.h>
54 #include <signal.h>
55 #include <stdint.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <time.h>
60 #include <unistd.h>
61 
62 #include "truss.h"
63 #include "extern.h"
64 #include "syscall.h"
65 
66 /*
67  * This should probably be in its own file.
68  */
69 
70 struct syscall syscalls[] = {
71 	{ "fcntl", 1, 3,
72 	  { { Int, 0 } , { Fcntl, 1 }, { Hex, 2 }}},
73 	{ "readlink", 1, 3,
74 	  { { String, 0 } , { Readlinkres | OUT, 1 }, { Int, 2 }}},
75 	{ "lseek", 2, 3,
76 #ifdef __LP64__
77 	  { { Int, 0 }, {Quad, 2 }, { Whence, 3 }}},
78 #else
79 	  { { Int, 0 }, {Quad, 2 }, { Whence, 4 }}},
80 #endif
81 	{ "linux_lseek", 2, 3,
82 	  { { Int, 0 }, {Int, 1 }, { Whence, 2 }}},
83 	{ "mmap", 2, 6,
84 #ifdef __LP64__
85 	  { { Ptr, 0 }, {Int, 1}, {Mprot, 2}, {Mmapflags, 3}, {Int, 4}, {Quad, 5}}},
86 #else
87 	  { { Ptr, 0 }, {Int, 1}, {Mprot, 2}, {Mmapflags, 3}, {Int, 4}, {Quad, 6}}},
88 #endif
89 	{ "mprotect", 1, 3,
90 	  { { Ptr, 0 }, {Int, 1}, {Mprot, 2}}},
91 	{ "open", 1, 3,
92 	  { { String | IN, 0} , { Hex, 1}, {Octal, 2}}},
93 	{ "mkdir", 1, 2,
94 	  { { String, 0} , {Octal, 1}}},
95 	{ "linux_open", 1, 3,
96 	  { { String, 0 }, { Hex, 1}, { Octal, 2 }}},
97 	{ "close", 1, 1,
98 	  { { Int, 0 } } },
99 	{ "link", 0, 2,
100 	  { { String, 0 }, { String, 1 }}},
101 	{ "unlink", 0, 1,
102 	  { { String, 0 }}},
103 	{ "chdir", 0, 1,
104 	  { { String, 0 }}},
105 	{ "chroot", 0, 1,
106 	  { { String, 0 }}},
107 	{ "mknod", 0, 3,
108 	  { { String, 0 }, { Octal, 1 }, { Int, 3 }}},
109 	{ "chmod", 0, 2,
110 	  { { String, 0 }, { Octal, 1 }}},
111 	{ "chown", 0, 3,
112 	  { { String, 0 }, { Int, 1 }, { Int, 2 }}},
113 	{ "mount", 0, 4,
114 	  { { String, 0 }, { String, 1 }, { Int, 2 }, { Ptr, 3 }}},
115 	{ "umount", 0, 2,
116 	  { { String, 0 }, { Int, 2 }}},
117 	{ "fstat", 1, 2,
118 	  { { Int, 0},  {Ptr | OUT , 1 }}},
119 	{ "stat", 1, 2,
120 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
121 	{ "lstat", 1, 2,
122 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
123 	{ "linux_newstat", 1, 2,
124 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
125 	{ "linux_newfstat", 1, 2,
126 	  { { Int, 0 }, { Ptr | OUT, 1 }}},
127 	{ "write", 1, 3,
128 	  { { Int, 0 }, { Ptr | IN, 1 }, { Int, 2 }}},
129 	{ "ioctl", 1, 3,
130 	  { { Int, 0 }, { Ioctl, 1 }, { Hex, 2 }}},
131 	{ "break", 1, 1, { { Hex, 0 }}},
132 	{ "exit", 0, 1, { { Hex, 0 }}},
133 	{ "access", 1, 2, { { String | IN, 0 }, { Int, 1 }}},
134 	{ "sigaction", 1, 3,
135 	  { { Signal, 0 }, { Sigaction | IN, 1 }, { Sigaction | OUT, 2 }}},
136 	{ "accept", 1, 3,
137 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
138 	{ "bind", 1, 3,
139 	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
140 	{ "connect", 1, 3,
141 	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
142 	{ "getpeername", 1, 3,
143 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
144 	{ "getsockname", 1, 3,
145 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
146 	{ "recvfrom", 1, 6,
147 	  { { Hex, 0 }, { Ptr | IN, 1 }, { Int, 3 }, { Hex, 3 }, { Sockaddr | OUT, 4 }, { Ptr | OUT, 5 } } },
148 	{ "sendto", 1, 6,
149 	  { { Hex, 0 }, { Ptr | IN, 1 }, { Int, 3 }, { Hex, 3 }, { Sockaddr | IN, 4 }, { Ptr | IN, 5 } } },
150 	{ "execve", 1, 3,
151 	  { { String | IN, 0 }, { StringArray | IN, 1 }, { StringArray | IN, 2 } } },
152 	{ "linux_execve", 1, 3,
153 	  { { String | IN, 0 }, { StringArray | IN, 1 }, { StringArray | IN, 2 } } },
154 	{ "kldload", 0, 1, { { String | IN, 0 }}},
155 	{ "kldunload", 0, 1, { { Int, 0 }}},
156 	{ "kldfind", 0, 1, { { String | IN, 0 }}},
157 	{ "kldnext", 0, 1, { { Int, 0 }}},
158 	{ "kldstat", 0, 2, { { Int, 0 }, { Ptr, 1 }}},
159 	{ "kldfirstmod", 0, 1, { { Int, 0 }}},
160 	{ "nanosleep", 0, 1, { { Timespec, 0 }}},
161 	{ "select", 1, 5, { { Int, 0 }, { Fd_set, 1 }, { Fd_set, 2 }, { Fd_set, 3 }, { Timeval, 4 }}},
162 	{ "poll", 1, 3, { { Pollfd, 0 }, { Int, 1 }, { Int, 2 }}},
163 	{ "gettimeofday", 1, 2, { { Timeval | OUT, 0 }, { Ptr, 1 }}},
164 	{ "clock_gettime", 1, 2, { { Int, 0 }, { Timeval | OUT, 1 }}},
165 	{ "recvfrom", 1, 6, { { Int, 0 }, { Ptr | OUT, 1 }, { Int, 2 }, { Int, 3 }, { Sockaddr | OUT, 4}, {Ptr | OUT, 5}}},
166 	{ "getitimer", 1, 2, { { Int, 0 }, { Itimerval | OUT, 2 }}},
167 	{ "setitimer", 1, 3, { { Int, 0 }, { Itimerval, 1} , { Itimerval | OUT, 2 }}},
168 	{ "utimes", 1, 2,
169 		{ { String | IN, 0 }, { Timeval | IN, 1 }}},
170 	{ "lutimes", 1, 2,
171 		{ { String | IN, 0 }, { Timeval | IN, 1 }}},
172 	{ "futimes", 1, 2,
173 		{ { Int, 0 }, { Timeval | IN, 1 }}},
174 	{ "chflags", 1, 2,
175 		{ { String | IN, 0 }, { Hex, 1 }}},
176 	{ "lchflags", 1, 2,
177 		{ { String | IN, 0 }, { Hex, 1 }}},
178 	{ 0, 0, 0, { { 0, 0 }}},
179 };
180 
181 /*
182  * If/when the list gets big, it might be desirable to do it
183  * as a hash table or binary search.
184  */
185 
186 struct syscall *
187 get_syscall(const char *name) {
188 	struct syscall *sc = syscalls;
189 
190 	if (name == NULL)
191 		return (NULL);
192 	while (sc->name) {
193 		if (!strcmp(name, sc->name))
194 			return sc;
195 		sc++;
196 	}
197 	return NULL;
198 }
199 
200 /*
201  * get_struct
202  *
203  * Copy a fixed amount of bytes from the process.
204  */
205 
206 static int
207 get_struct(int procfd, void *offset, void *buf, int len) {
208 
209 	if (pread(procfd, buf, len, (uintptr_t)offset) != len)
210 		return -1;
211 	return 0;
212 }
213 
214 /*
215  * get_string
216  * Copy a string from the process.  Note that it is
217  * expected to be a C string, but if max is set, it will
218  * only get that much.
219  */
220 
221 char *
222 get_string(int procfd, void *offset, int max) {
223 	char *buf;
224 	int size, len, c, fd;
225 	FILE *p;
226 
227 	if ((fd = dup(procfd)) == -1)
228 		err(1, "dup");
229 	if ((p = fdopen(fd, "r")) == NULL)
230 		err(1, "fdopen");
231 	buf = malloc( size = (max ? max : 64 ) );
232 	len = 0;
233 	buf[0] = 0;
234 	if (fseeko(p, (uintptr_t)offset, SEEK_SET) == 0) {
235 		while ((c = fgetc(p)) != EOF) {
236 			buf[len++] = c;
237 			if (c == 0 || len == max) {
238 				buf[len] = 0;
239 				break;
240 			}
241 			if (len == size) {
242 				char *tmp;
243 				tmp = realloc(buf, size+64);
244 				if (tmp == NULL) {
245 					buf[len] = 0;
246 					break;
247 				}
248 				size += 64;
249 				buf = tmp;
250 			}
251 		}
252 	}
253 	fclose(p);
254 	return (buf);
255 }
256 
257 
258 /*
259  * Remove a trailing '|' in a string, useful for fixup after decoding
260  * a "flags" argument.
261  */
262 
263 void
264 remove_trailing_or(char *str)
265 {
266 
267 	if (str != NULL && (str = rindex(str, '|')) != NULL && str[1] == '\0')
268 		*str = '\0';
269 }
270 
271 /*
272  * print_arg
273  * Converts a syscall argument into a string.  Said string is
274  * allocated via malloc(), so needs to be free()'d.  The file
275  * descriptor is for the process' memory (via /proc), and is used
276  * to get any data (where the argument is a pointer).  sc is
277  * a pointer to the syscall description (see above); args is
278  * an array of all of the system call arguments.
279  */
280 
281 char *
282 print_arg(int fd, struct syscall_args *sc, unsigned long *args, long retval) {
283   char *tmp = NULL;
284   switch (sc->type & ARG_MASK) {
285   case Hex:
286     asprintf(&tmp, "0x%lx", args[sc->offset]);
287     break;
288   case Octal:
289     asprintf(&tmp, "0%lo", args[sc->offset]);
290     break;
291   case Int:
292     asprintf(&tmp, "%ld", args[sc->offset]);
293     break;
294   case String:
295     {
296       char *tmp2;
297       tmp2 = get_string(fd, (void*)args[sc->offset], 0);
298       asprintf(&tmp, "\"%s\"", tmp2);
299       free(tmp2);
300     }
301   break;
302   case StringArray:
303     {
304       int num, size, i;
305       char *tmp2;
306       char *string;
307       char *strarray[100];	/* XXX This is ugly. */
308 
309       if (get_struct(fd, (void *)args[sc->offset], (void *)&strarray,
310                      sizeof(strarray)) == -1) {
311 	err(1, "get_struct %p", (void *)args[sc->offset]);
312       }
313       num = 0;
314       size = 0;
315 
316       /* Find out how large of a buffer we'll need. */
317       while (strarray[num] != NULL) {
318 	string = get_string(fd, (void*)strarray[num], 0);
319         size += strlen(string);
320 	free(string);
321 	num++;
322       }
323       size += 4 + (num * 4);
324       tmp = (char *)malloc(size);
325       tmp2 = tmp;
326 
327       tmp2 += sprintf(tmp2, " [");
328       for (i = 0; i < num; i++) {
329 	string = get_string(fd, (void*)strarray[i], 0);
330         tmp2 += sprintf(tmp2, " \"%s\"%c", string, (i+1 == num) ? ' ' : ',');
331 	free(string);
332       }
333       tmp2 += sprintf(tmp2, "]");
334     }
335   break;
336 #ifdef __LP64__
337   case Quad:
338     asprintf(&tmp, "0x%lx", args[sc->offset]);
339     break;
340 #else
341   case Quad:
342     {
343       unsigned long long ll;
344       ll = *(unsigned long long *)(args + sc->offset);
345       asprintf(&tmp, "0x%llx", ll);
346       break;
347     }
348 #endif
349   case Ptr:
350     asprintf(&tmp, "0x%lx", args[sc->offset]);
351     break;
352   case Readlinkres:
353     {
354       char *tmp2;
355       if (retval == -1) {
356 	tmp = strdup("");
357 	break;
358       }
359       tmp2 = get_string(fd, (void*)args[sc->offset], retval);
360       asprintf(&tmp, "\"%s\"", tmp2);
361       free(tmp2);
362     }
363   break;
364   case Ioctl:
365     {
366       const char *temp = ioctlname(args[sc->offset]);
367       if (temp)
368 	tmp = strdup(temp);
369       else
370 	asprintf(&tmp, "0x%lx", args[sc->offset]);
371     }
372     break;
373   case Timespec:
374     {
375       struct timespec ts;
376       if (get_struct(fd, (void *)args[sc->offset], &ts, sizeof(ts)) != -1)
377 	asprintf(&tmp, "{%jd %jd}", (intmax_t)ts.tv_sec, (intmax_t)ts.tv_nsec);
378       else
379 	asprintf(&tmp, "0x%lx", args[sc->offset]);
380     }
381     break;
382   case Timeval:
383     {
384       struct timeval tv;
385       if (get_struct(fd, (void *)args[sc->offset], &tv, sizeof(tv)) != -1)
386 	asprintf(&tmp, "{%jd %jd}", (intmax_t)tv.tv_sec, (intmax_t)tv.tv_usec);
387       else
388 	asprintf(&tmp, "0x%lx", args[sc->offset]);
389     }
390     break;
391   case Itimerval:
392     {
393       struct itimerval itv;
394       if (get_struct(fd, (void *)args[sc->offset], &itv, sizeof(itv)) != -1)
395 	asprintf(&tmp, "{%jd %jd, %jd %jd}",
396 	    (intmax_t)itv.it_interval.tv_sec,
397 	    (intmax_t)itv.it_interval.tv_usec,
398 	    (intmax_t)itv.it_value.tv_sec,
399 	    (intmax_t)itv.it_value.tv_usec);
400       else
401 	asprintf(&tmp, "0x%lx", args[sc->offset]);
402     }
403     break;
404   case Pollfd:
405     {
406       /*
407        * XXX: A Pollfd argument expects the /next/ syscall argument to be
408        * the number of fds in the array. This matches the poll syscall.
409        */
410       struct pollfd *pfd;
411       int numfds = args[sc->offset+1];
412       int bytes = sizeof(struct pollfd) * numfds;
413       int i, tmpsize, u, used;
414       const int per_fd = 100;
415 
416       if ((pfd = malloc(bytes)) == NULL)
417 	err(1, "Cannot malloc %d bytes for pollfd array", bytes);
418       if (get_struct(fd, (void *)args[sc->offset], pfd, bytes) != -1) {
419 
420 	used = 0;
421 	tmpsize = 1 + per_fd * numfds + 2;
422 	if ((tmp = malloc(tmpsize)) == NULL)
423 	  err(1, "Cannot alloc %d bytes for poll output", tmpsize);
424 
425 	tmp[used++] = '{';
426 	for (i = 0; i < numfds; i++) {
427 #define POLLKNOWN_EVENTS \
428 	(POLLIN | POLLPRI | POLLOUT | POLLERR | POLLHUP | POLLNVAL | \
429 	 POLLRDNORM |POLLRDBAND | POLLWRBAND | POLLINIGNEOF)
430 
431 	  u = snprintf(tmp + used, per_fd,
432 	    "%s%d 0x%hx%s%s%s%s%s%s%s%s%s ",
433 	    i > 0 ? " " : "",
434 	    pfd[i].fd,
435 	    pfd[i].events & ~POLLKNOWN_EVENTS,
436 	    pfd[i].events & POLLIN ? "" : "|IN",
437 	    pfd[i].events & POLLPRI ? "" : "|PRI",
438 	    pfd[i].events & POLLOUT ? "" : "|OUT",
439 	    pfd[i].events & POLLERR ? "" : "|ERR",
440 	    pfd[i].events & POLLHUP ? "" : "|HUP",
441 	    pfd[i].events & POLLNVAL ? "" : "|NVAL",
442 	    pfd[i].events & POLLRDNORM ? "" : "|RDNORM",
443 	    pfd[i].events & POLLRDBAND ? "" : "|RDBAND",
444 	    pfd[i].events & POLLWRBAND ? "" : "|WRBAND");
445 	  if (u > 0)
446 	    used += u < per_fd ? u : per_fd;
447 	}
448 	tmp[used++] = '}';
449 	tmp[used++] = '\0';
450       } else
451 	asprintf(&tmp, "0x%lx", args[sc->offset]);
452       free(pfd);
453     }
454     break;
455   case Fd_set:
456     {
457       /*
458        * XXX: A Fd_set argument expects the /first/ syscall argument to be
459        * the number of fds in the array.  This matches the select syscall.
460        */
461       fd_set *fds;
462       int numfds = args[0];
463       int bytes = _howmany(numfds, _NFDBITS) * _NFDBITS;
464       int i, tmpsize, u, used;
465       const int per_fd = 20;
466 
467       if ((fds = malloc(bytes)) == NULL)
468 	err(1, "Cannot malloc %d bytes for fd_set array", bytes);
469       if (get_struct(fd, (void *)args[sc->offset], fds, bytes) != -1) {
470 	used = 0;
471 	tmpsize = 1 + numfds * per_fd + 2;
472 	if ((tmp = malloc(tmpsize)) == NULL)
473 	  err(1, "Cannot alloc %d bytes for fd_set output", tmpsize);
474 
475 	tmp[used++] = '{';
476 	for (i = 0; i < numfds; i++) {
477 	  if (FD_ISSET(i, fds)) {
478 	    u = snprintf(tmp + used, per_fd, "%d ", i);
479 	    if (u > 0)
480 	      used += u < per_fd ? u : per_fd;
481 	  }
482 	}
483 	if (tmp[used-1] == ' ')
484 		used--;
485 	tmp[used++] = '}';
486 	tmp[used++] = '\0';
487       } else
488 	asprintf(&tmp, "0x%lx", args[sc->offset]);
489       free(fds);
490     }
491     break;
492   case Signal:
493     {
494       long sig;
495 
496       sig = args[sc->offset];
497       tmp = strsig(sig);
498       if (tmp == NULL)
499         asprintf(&tmp, "%ld", sig);
500     }
501     break;
502   case Fcntl:
503     {
504 	switch (args[sc->offset]) {
505 #define S(a)	case a: tmp = strdup(#a); break;
506 	S(F_DUPFD);
507 	S(F_GETFD);
508 	S(F_SETFD);
509 	S(F_GETFL);
510 	S(F_SETFL);
511 	S(F_GETOWN);
512 	S(F_SETOWN);
513 	S(F_GETLK);
514 	S(F_SETLK);
515 	S(F_SETLKW);
516 #undef S
517 	}
518 	if (tmp == NULL)
519     		asprintf(&tmp, "0x%lx", args[sc->offset]);
520     }
521     break;
522 
523   case Mprot:
524     {
525 
526 #define S(a)	((args[sc->offset] & a) ? #a "|" : "")
527 	    asprintf(&tmp, "(0x%lx)%s%s%s%s", args[sc->offset],
528 		S(PROT_NONE), S(PROT_READ), S(PROT_WRITE), S(PROT_EXEC));
529 #undef S
530 	    remove_trailing_or(tmp);
531 
532     }
533     break;
534 
535   case Mmapflags:
536     {
537 #define S(a)	((args[sc->offset] & a) ? #a "|" : "")
538 	    asprintf(&tmp, "(0x%lx)%s%s%s%s%s%s%s%s", args[sc->offset],
539 		S(MAP_ANON), S(MAP_FIXED), S(MAP_HASSEMAPHORE),
540 		S(MAP_NOCORE), S(MAP_NOSYNC), S(MAP_PRIVATE),
541 		S(MAP_SHARED), S(MAP_STACK));
542 #undef S
543 
544 	    remove_trailing_or(tmp);
545     }
546     break;
547 
548   case Whence:
549     {
550 	switch (args[sc->offset]) {
551 #define S(a)	case a: tmp = strdup(#a); break;
552 	S(SEEK_SET);
553 	S(SEEK_CUR);
554 	S(SEEK_END);
555 #undef S
556 	default: asprintf(&tmp, "0x%lx", args[sc->offset]); break;
557 	}
558     }
559     break;
560   case Sockaddr:
561     {
562       struct sockaddr_storage ss;
563       char addr[64];
564       struct sockaddr_in *lsin;
565       struct sockaddr_in6 *lsin6;
566       struct sockaddr_un *sun;
567       struct sockaddr *sa;
568       char *p;
569       u_char *q;
570       int i;
571 
572       if (args[sc->offset] == 0) {
573 	      asprintf(&tmp, "NULL");
574 	      break;
575       }
576 
577       /* yuck: get ss_len */
578       if (get_struct(fd, (void *)args[sc->offset], (void *)&ss,
579 	sizeof(ss.ss_len) + sizeof(ss.ss_family)) == -1)
580 	err(1, "get_struct %p", (void *)args[sc->offset]);
581       /*
582        * If ss_len is 0, then try to guess from the sockaddr type.
583        * AF_UNIX may be initialized incorrectly, so always frob
584        * it by using the "right" size.
585        */
586       if (ss.ss_len == 0 || ss.ss_family == AF_UNIX) {
587 	      switch (ss.ss_family) {
588 	      case AF_INET:
589 		      ss.ss_len = sizeof(*lsin);
590 		      break;
591 	      case AF_UNIX:
592 		      ss.ss_len = sizeof(*sun);
593 		      break;
594 	      default:
595 		      /* hurrrr */
596 		      break;
597 	      }
598       }
599       if (get_struct(fd, (void *)args[sc->offset], (void *)&ss, ss.ss_len)
600 	  == -1) {
601 	  err(2, "get_struct %p", (void *)args[sc->offset]);
602       }
603 
604       switch (ss.ss_family) {
605       case AF_INET:
606 	lsin = (struct sockaddr_in *)&ss;
607 	inet_ntop(AF_INET, &lsin->sin_addr, addr, sizeof addr);
608 	asprintf(&tmp, "{ AF_INET %s:%d }", addr, htons(lsin->sin_port));
609 	break;
610       case AF_INET6:
611 	lsin6 = (struct sockaddr_in6 *)&ss;
612 	inet_ntop(AF_INET6, &lsin6->sin6_addr, addr, sizeof addr);
613 	asprintf(&tmp, "{ AF_INET6 [%s]:%d }", addr, htons(lsin6->sin6_port));
614 	break;
615       case AF_UNIX:
616         sun = (struct sockaddr_un *)&ss;
617         asprintf(&tmp, "{ AF_UNIX \"%s\" }", sun->sun_path);
618 	break;
619       default:
620 	sa = (struct sockaddr *)&ss;
621         asprintf(&tmp, "{ sa_len = %d, sa_family = %d, sa_data = {%n%*s } }",
622 	  (int)sa->sa_len, (int)sa->sa_family, &i,
623 	  6 * (int)(sa->sa_len - ((char *)&sa->sa_data - (char *)sa)), "");
624 	if (tmp != NULL) {
625 	  p = tmp + i;
626           for (q = (u_char *)&sa->sa_data; q < (u_char *)sa + sa->sa_len; q++)
627             p += sprintf(p, " %#02x,", *q);
628 	}
629       }
630     }
631     break;
632   case Sigaction:
633     {
634       struct sigaction sa;
635       char *hand;
636       const char *h;
637 #define SA_KNOWN_FLAGS \
638 	(SA_ONSTACK | SA_RESTART | SA_RESETHAND | SA_NOCLDSTOP | SA_NODEFER | \
639 	 SA_NOCLDWAIT | SA_SIGINFO)
640 
641 
642       if (get_struct(fd, (void *)args[sc->offset], &sa, sizeof(sa)) != -1) {
643 
644 	asprintf(&hand, "%p", sa.sa_handler);
645 	if (sa.sa_handler == SIG_DFL)
646 	  h = "SIG_DFL";
647 	else if (sa.sa_handler == SIG_IGN)
648 	  h = "SIG_IGN";
649 	else
650 	  h = hand;
651 	asprintf(&tmp, "{ %s 0x%x%s%s%s%s%s%s%s ss_t }",
652 	    h,
653 	    sa.sa_flags & ~SA_KNOWN_FLAGS,
654 	    sa.sa_flags & SA_ONSTACK ? "" : "|ONSTACK",
655 	    sa.sa_flags & SA_RESTART ? "" : "|RESTART",
656 	    sa.sa_flags & SA_RESETHAND ? "" : "|RESETHAND",
657 	    sa.sa_flags & SA_NOCLDSTOP ? "" : "|NOCLDSTOP",
658 	    sa.sa_flags & SA_NODEFER ? "" : "|NODEFER",
659 	    sa.sa_flags & SA_NOCLDWAIT ? "" : "|NOCLDWAIT",
660 	    sa.sa_flags & SA_SIGINFO ? "" : "|SIGINFO");
661 	free(hand);
662       } else
663 	asprintf(&tmp, "0x%lx", args[sc->offset]);
664 
665     }
666     break;
667   }
668   return tmp;
669 }
670 
671 #define timespecsubt(tvp, uvp, vvp)					\
672 	do {								\
673 		(vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;		\
674 		(vvp)->tv_nsec = (tvp)->tv_nsec - (uvp)->tv_nsec;	\
675 		if ((vvp)->tv_nsec < 0) {				\
676 			(vvp)->tv_sec--;				\
677 			(vvp)->tv_nsec += 1000000000;			\
678 		}							\
679 	} while (0)
680 
681 /*
682  * print_syscall
683  * Print (to outfile) the system call and its arguments.  Note that
684  * nargs is the number of arguments (not the number of words; this is
685  * potentially confusing, I know).
686  */
687 
688 void
689 print_syscall(struct trussinfo *trussinfo, const char *name, int nargs, char **s_args) {
690   int i;
691   int len = 0;
692   struct timespec timediff;
693 
694   if (trussinfo->flags & FOLLOWFORKS)
695     len += fprintf(trussinfo->outfile, "%5d: ", trussinfo->pid);
696 
697   if (name != NULL && (!strcmp(name, "execve") || !strcmp(name, "exit"))) {
698     clock_gettime(CLOCK_REALTIME, &trussinfo->after);
699   }
700 
701   if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
702     timespecsubt(&trussinfo->after, &trussinfo->start_time, &timediff);
703     len += fprintf(trussinfo->outfile, "%ld.%09ld ",
704 		   (long)timediff.tv_sec, timediff.tv_nsec);
705   }
706 
707   if (trussinfo->flags & RELATIVETIMESTAMPS) {
708     timespecsubt(&trussinfo->after, &trussinfo->before, &timediff);
709     len += fprintf(trussinfo->outfile, "%ld.%09ld ",
710 		   (long)timediff.tv_sec, timediff.tv_nsec);
711   }
712 
713   len += fprintf(trussinfo->outfile, "%s(", name);
714 
715   for (i = 0; i < nargs; i++) {
716     if (s_args[i])
717       len += fprintf(trussinfo->outfile, "%s", s_args[i]);
718     else
719       len += fprintf(trussinfo->outfile, "<missing argument>");
720     len += fprintf(trussinfo->outfile, "%s", i < (nargs - 1) ? "," : "");
721   }
722   len += fprintf(trussinfo->outfile, ")");
723   for (i = 0; i < 6 - (len / 8); i++)
724 	fprintf(trussinfo->outfile, "\t");
725 }
726 
727 void
728 print_syscall_ret(struct trussinfo *trussinfo, const char *name, int nargs,
729     char **s_args, int errorp, long retval)
730 {
731   print_syscall(trussinfo, name, nargs, s_args);
732   if (errorp) {
733     fprintf(trussinfo->outfile, " ERR#%ld '%s'\n", retval, strerror(retval));
734   } else {
735     fprintf(trussinfo->outfile, " = %ld (0x%lx)\n", retval, retval);
736   }
737 }
738