xref: /freebsd/usr.bin/truss/syscalls.c (revision 5773cccf19ef7b97e56c1101aa481c43149224da)
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/types.h>
43 #include <sys/socket.h>
44 #include <sys/time.h>
45 #include <sys/un.h>
46 #include <netinet/in.h>
47 #include <arpa/inet.h>
48 
49 #include <ctype.h>
50 #include <err.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 /*
63  * This should probably be in its own file.
64  */
65 
66 struct syscall syscalls[] = {
67 	{ "readlink", 1, 3,
68 	  { { String, 0 } , { String | OUT, 1 }, { Int, 2 }}},
69 	{ "lseek", 2, 3,
70 	  { { Int, 0 }, {Quad, 2 }, { Int, 4 }}},
71 	{ "mmap", 2, 6,
72 	  { { Hex, 0 }, {Int, 1}, {Hex, 2}, {Hex, 3}, {Int, 4}, {Quad, 6}}},
73 	{ "open", 1, 3,
74 	  { { String | IN, 0} , { Hex, 1}, {Octal, 2}}},
75 	{ "linux_open", 1, 3,
76 	  { { String, 0 }, { Hex, 1}, { Octal, 2 }}},
77 	{ "close", 1, 1, { { Int, 0 } } },
78 	{ "fstat", 1, 2,
79 	  { { Int, 0},  {Ptr | OUT , 1 }}},
80 	{ "stat", 1, 2,
81 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
82 	{ "lstat", 1, 2,
83 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
84 	{ "linux_newstat", 1, 2,
85 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
86 	{ "linux_newfstat", 1, 2,
87 	  { { Int, 0 }, { Ptr | OUT, 1 }}},
88 	{ "write", 1, 3,
89 	  { { Int, 0}, { Ptr | IN, 1 }, { Int, 2 }}},
90 	{ "ioctl", 1, 3,
91 	  { { Int, 0}, { Ioctl, 1 }, { Hex, 2 }}},
92 	{ "break", 1, 1, { { Hex, 0 }}},
93 	{ "exit", 0, 1, { { Hex, 0 }}},
94 	{ "access", 1, 2, { { String | IN, 0 }, { Int, 1 }}},
95 	{ "sigaction", 1, 3,
96 	  { { Signal, 0 }, { Ptr | IN, 1 }, { Ptr | OUT, 2 }}},
97 	{ "accept", 1, 3,
98 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
99 	{ "bind", 1, 3,
100 	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
101 	{ "connect", 1, 3,
102 	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
103 	{ "getpeername", 1, 3,
104 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
105 	{ "getsockname", 1, 3,
106 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
107 	{ "execve", 1, 3,
108 	  { { String | IN, 0 }, { StringArray | IN, 1 }, { StringArray | IN, 2 } } },
109 	{ "linux_execve", 1, 3,
110 	  { { String | IN, 0 }, { StringArray | IN, 1 }, { StringArray | IN, 2 } } },
111 	{ 0, 0, 0, { { 0, 0 }}},
112 };
113 
114 /*
115  * If/when the list gets big, it might be desirable to do it
116  * as a hash table or binary search.
117  */
118 
119 struct syscall *
120 get_syscall(const char *name) {
121 	struct syscall *sc = syscalls;
122 
123 	while (sc->name) {
124 		if (!strcmp(name, sc->name))
125 			return sc;
126 		sc++;
127 	}
128 	return NULL;
129 }
130 
131 /*
132  * get_struct
133  *
134  * Copy a fixed amount of bytes from the process.
135  */
136 
137 static int
138 get_struct(int procfd, void *offset, void *buf, int len) {
139 	char *pos;
140 	FILE *p;
141 	int c, fd;
142 
143 	if ((fd = dup(procfd)) == -1)
144 		err(1, "dup");
145 	if ((p = fdopen(fd, "r")) == NULL)
146 		err(1, "fdopen");
147 	fseeko(p, (uintptr_t)offset, SEEK_SET);
148 	for (pos = (char *)buf; len--; pos++) {
149 		if ((c = fgetc(p)) == EOF)
150 			return -1;
151 		*pos = c;
152 	}
153 	fclose(p);
154 	return 0;
155 }
156 
157 /*
158  * get_string
159  * Copy a string from the process.  Note that it is
160  * expected to be a C string, but if max is set, it will
161  * only get that much.
162  */
163 
164 char *
165 get_string(int procfd, void *offset, int max) {
166 	char *buf;
167 	int size, len, c, fd;
168 	FILE *p;
169 
170 	if ((fd = dup(procfd)) == -1)
171 		err(1, "dup");
172 	if ((p = fdopen(fd, "r")) == NULL)
173 		err(1, "fdopen");
174 	buf = malloc( size = (max ? max : 64 ) );
175 	len = 0;
176 	buf[0] = 0;
177 	fseeko(p, (uintptr_t)offset, SEEK_SET);
178 	while ((c = fgetc(p)) != EOF) {
179 		buf[len++] = c;
180 		if (c == 0 || len == max) {
181 			buf[len] = 0;
182 			break;
183 		}
184 		if (len == size) {
185 			char *tmp;
186 			tmp = realloc(buf, size+64);
187 			if (tmp == NULL) {
188 				buf[len] = 0;
189 				fclose(p);
190 				return buf;
191 			}
192 			size += 64;
193 			buf = tmp;
194 		}
195 	}
196 	fclose(p);
197 	return buf;
198 }
199 
200 
201 /*
202  * Gag.  This is really unportable.  Multiplication is more portable.
203  * But slower, from the code I saw.
204  */
205 
206 static long long
207 make_quad(unsigned long p1, unsigned long p2) {
208   union {
209     long long ll;
210     unsigned long l[2];
211   } t;
212   t.l[0] = p1;
213   t.l[1] = p2;
214   return t.ll;
215 }
216 
217 
218 /*
219  * print_arg
220  * Converts a syscall argument into a string.  Said string is
221  * allocated via malloc(), so needs to be free()'d.  The file
222  * descriptor is for the process' memory (via /proc), and is used
223  * to get any data (where the argument is a pointer).  sc is
224  * a pointer to the syscall description (see above); args is
225  * an array of all of the system call arguments.
226  */
227 
228 char *
229 print_arg(int fd, struct syscall_args *sc, unsigned long *args) {
230   char *tmp = NULL;
231   switch (sc->type & ARG_MASK) {
232   case Hex:
233     tmp = malloc(12);
234     sprintf(tmp, "0x%lx", args[sc->offset]);
235     break;
236   case Octal:
237     tmp = malloc(13);
238     sprintf(tmp, "0%lo", args[sc->offset]);
239     break;
240   case Int:
241     tmp = malloc(12);
242     sprintf(tmp, "%ld", args[sc->offset]);
243     break;
244   case String:
245     {
246       char *tmp2;
247       tmp2 = get_string(fd, (void*)args[sc->offset], 0);
248       tmp = malloc(strlen(tmp2) + 3);
249       sprintf(tmp, "\"%s\"", tmp2);
250       free(tmp2);
251     }
252   break;
253   case StringArray:
254     {
255       int num, size, i;
256       char *tmp2;
257       char *string;
258       char *strarray[100];	/* XXX This is ugly. */
259 
260       if (get_struct(fd, (void *)args[sc->offset], (void *)&strarray,
261                      sizeof(strarray)) == -1) {
262 	err(1, "get_struct %p", (void *)args[sc->offset]);
263       }
264       num = 0;
265       size = 0;
266 
267       /* Find out how large of a buffer we'll need. */
268       while (strarray[num] != NULL) {
269 	string = get_string(fd, (void*)strarray[num], 0);
270         size += strlen(string);
271 	free(string);
272 	num++;
273       }
274       size += 4 + (num * 4);
275       tmp = (char *)malloc(size);
276       tmp2 = tmp;
277 
278       tmp2 += sprintf(tmp2, " [");
279       for (i = 0; i < num; i++) {
280 	string = get_string(fd, (void*)strarray[i], 0);
281         tmp2 += sprintf(tmp2, " \"%s\"%c", string, (i+1 == num) ? ' ' : ',');
282 	free(string);
283       }
284       tmp2 += sprintf(tmp2, "]");
285     }
286   break;
287   case Quad:
288     {
289       unsigned long long t;
290       unsigned long l1, l2;
291       l1 = args[sc->offset];
292       l2 = args[sc->offset+1];
293       t = make_quad(l1, l2);
294       tmp = malloc(24);
295       sprintf(tmp, "0x%qx", t);
296       break;
297     }
298   case Ptr:
299     tmp = malloc(12);
300     sprintf(tmp, "0x%lx", args[sc->offset]);
301     break;
302   case Ioctl:
303     {
304       const char *temp = ioctlname(args[sc->offset]);
305       if (temp)
306 	tmp = strdup(temp);
307       else {
308 	tmp = malloc(12);
309 	sprintf(tmp, "0x%lx", args[sc->offset]);
310       }
311     }
312     break;
313   case Signal:
314     {
315       long sig;
316 
317       sig = args[sc->offset];
318       tmp = malloc(12);
319       if (sig > 0 && sig < NSIG) {
320 	int i;
321 	sprintf(tmp, "sig%s", sys_signame[sig]);
322 	for (i = 0; tmp[i] != '\0'; ++i)
323 	  tmp[i] = toupper(tmp[i]);
324       } else {
325         sprintf(tmp, "%ld", sig);
326       }
327     }
328     break;
329   case Sockaddr:
330     {
331       struct sockaddr_storage ss;
332       char addr[64];
333       struct sockaddr_in *lsin;
334       struct sockaddr_in6 *lsin6;
335       struct sockaddr_un *sun;
336       struct sockaddr *sa;
337       char *p;
338       u_char *q;
339       int i;
340 
341       /* yuck: get ss_len */
342       if (get_struct(fd, (void *)args[sc->offset], (void *)&ss,
343 	sizeof(ss.ss_len) + sizeof(ss.ss_family)) == -1)
344 	err(1, "get_struct %p", (void *)args[sc->offset]);
345       /* sockaddr_un never have the length filled in! */
346       if (ss.ss_family == AF_UNIX) {
347 	if (get_struct(fd, (void *)args[sc->offset], (void *)&ss,
348 	  sizeof(*sun))
349 	  == -1)
350 	  err(2, "get_struct %p", (void *)args[sc->offset]);
351       } else {
352 	if (get_struct(fd, (void *)args[sc->offset], (void *)&ss, ss.ss_len)
353 	  == -1)
354 	  err(2, "get_struct %p", (void *)args[sc->offset]);
355       }
356 
357       switch (ss.ss_family) {
358       case AF_INET:
359 	lsin = (struct sockaddr_in *)&ss;
360 	inet_ntop(AF_INET, &lsin->sin_addr, addr, sizeof addr);
361 	asprintf(&tmp, "{ AF_INET %s:%d }", addr, htons(lsin->sin_port));
362 	break;
363       case AF_INET6:
364 	lsin6 = (struct sockaddr_in6 *)&ss;
365 	inet_ntop(AF_INET6, &lsin6->sin6_addr, addr, sizeof addr);
366 	asprintf(&tmp, "{ AF_INET6 [%s]:%d }", addr, htons(lsin6->sin6_port));
367 	break;
368       case AF_UNIX:
369         sun = (struct sockaddr_un *)&ss;
370         asprintf(&tmp, "{ AF_UNIX \"%s\" }", sun->sun_path);
371 	break;
372       default:
373 	sa = (struct sockaddr *)&ss;
374         asprintf(&tmp, "{ sa_len = %d, sa_family = %d, sa_data = {%n%*s } }",
375 	  (int)sa->sa_len, (int)sa->sa_family, &i,
376 	  6 * (int)(sa->sa_len - ((char *)&sa->sa_data - (char *)sa)), "");
377 	if (tmp != NULL) {
378 	  p = tmp + i;
379           for (q = (u_char *)&sa->sa_data; q < (u_char *)sa + sa->sa_len; q++)
380             p += sprintf(p, " %#02x,", *q);
381 	}
382       }
383     }
384     break;
385   }
386   return tmp;
387 }
388 
389 #define timespecsubt(tvp, uvp, vvp)					\
390 	do {								\
391 		(vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;		\
392 		(vvp)->tv_nsec = (tvp)->tv_nsec - (uvp)->tv_nsec;	\
393 		if ((vvp)->tv_nsec < 0) {				\
394 			(vvp)->tv_sec--;				\
395 			(vvp)->tv_nsec += 1000000000;			\
396 		}							\
397 	} while (0)
398 
399 /*
400  * print_syscall
401  * Print (to outfile) the system call and its arguments.  Note that
402  * nargs is the number of arguments (not the number of words; this is
403  * potentially confusing, I know).
404  */
405 
406 void
407 print_syscall(struct trussinfo *trussinfo, const char *name, int nargs, char **s_args) {
408   int i;
409   int len = 0;
410   struct timespec timediff;
411 
412   if (trussinfo->flags & FOLLOWFORKS)
413     len += fprintf(trussinfo->outfile, "%5d: ", trussinfo->pid);
414 
415   if (name != NULL && (!strcmp(name, "execve") || !strcmp(name, "exit"))) {
416     clock_gettime(CLOCK_REALTIME, &trussinfo->after);
417   }
418 
419   if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
420     timespecsubt(&trussinfo->after, &trussinfo->start_time, &timediff);
421     len += fprintf(trussinfo->outfile, "%ld.%09ld ",
422 		   (long)timediff.tv_sec, timediff.tv_nsec);
423   }
424 
425   if (trussinfo->flags & RELATIVETIMESTAMPS) {
426     timespecsubt(&trussinfo->after, &trussinfo->before, &timediff);
427     len += fprintf(trussinfo->outfile, "%ld.%09ld ",
428 		   (long)timediff.tv_sec, timediff.tv_nsec);
429   }
430 
431   len += fprintf(trussinfo->outfile, "%s(", name);
432 
433   for (i = 0; i < nargs; i++) {
434     if (s_args[i])
435       len += fprintf(trussinfo->outfile, "%s", s_args[i]);
436     else
437       len += fprintf(trussinfo->outfile, "<missing argument>");
438     len += fprintf(trussinfo->outfile, "%s", i < (nargs - 1) ? "," : "");
439   }
440   len += fprintf(trussinfo->outfile, ")");
441   for (i = 0; i < 6 - (len / 8); i++)
442 	fprintf(trussinfo->outfile, "\t");
443 }
444 
445 void
446 print_syscall_ret(struct trussinfo *trussinfo, const char *name, int nargs, char **s_args, int errorp, int retval) {
447   print_syscall(trussinfo, name, nargs, s_args);
448   if (errorp) {
449     fprintf(trussinfo->outfile, " ERR#%d '%s'\n", retval, strerror(retval));
450   } else {
451     fprintf(trussinfo->outfile, " = %d (0x%x)\n", retval, retval);
452   }
453 }
454