xref: /freebsd/usr.bin/truss/syscalls.c (revision 77b7cdf1999ee965ad494fddd184b18f532ac91a)
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,
78 	  { { Int, 0 } } },
79 	{ "link", 0, 2,
80 	  { { String, 0 }, { String, 1 }}},
81 	{ "unlink", 0, 1,
82 	  { { String, 0 }}},
83 	{ "chdir", 0, 1,
84 	  { { String, 0 }}},
85 	{ "mknod", 0, 3,
86 	  { { String, 0 }, { Octal, 1 }, { Int, 3 }}},
87 	{ "chmod", 0, 2,
88 	  { { String, 0 }, { Octal, 1 }}},
89 	{ "chown", 0, 3,
90 	  { { String, 0 }, { Int, 1 }, { Int, 2 }}},
91 	{ "mount", 0, 4,
92 	  { { String, 0 }, { String, 1 }, { Int, 2 }, { Ptr, 3 }}},
93 	{ "umount", 0, 2,
94 	  { { String, 0 }, { Int, 2 }}},
95 	{ "fstat", 1, 2,
96 	  { { Int, 0},  {Ptr | OUT , 1 }}},
97 	{ "stat", 1, 2,
98 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
99 	{ "lstat", 1, 2,
100 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
101 	{ "linux_newstat", 1, 2,
102 	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
103 	{ "linux_newfstat", 1, 2,
104 	  { { Int, 0 }, { Ptr | OUT, 1 }}},
105 	{ "write", 1, 3,
106 	  { { Int, 0}, { Ptr | IN, 1 }, { Int, 2 }}},
107 	{ "ioctl", 1, 3,
108 	  { { Int, 0}, { Ioctl, 1 }, { Hex, 2 }}},
109 	{ "break", 1, 1, { { Hex, 0 }}},
110 	{ "exit", 0, 1, { { Hex, 0 }}},
111 	{ "access", 1, 2, { { String | IN, 0 }, { Int, 1 }}},
112 	{ "sigaction", 1, 3,
113 	  { { Signal, 0 }, { Ptr | IN, 1 }, { Ptr | OUT, 2 }}},
114 	{ "accept", 1, 3,
115 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
116 	{ "bind", 1, 3,
117 	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
118 	{ "connect", 1, 3,
119 	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
120 	{ "getpeername", 1, 3,
121 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
122 	{ "getsockname", 1, 3,
123 	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
124 	{ "execve", 1, 3,
125 	  { { String | IN, 0 }, { StringArray | IN, 1 }, { StringArray | IN, 2 } } },
126 	{ "linux_execve", 1, 3,
127 	  { { String | IN, 0 }, { StringArray | IN, 1 }, { StringArray | IN, 2 } } },
128 	{ "kldload", 0, 1, { { String | IN, 0 }}},
129 	{ "kldunload", 0, 1, { { Int, 0 }}},
130 	{ "kldfind", 0, 1, { { String | IN, 0 }}},
131 	{ "kldnext", 0, 1, { { Int, 0 }}},
132 	{ "kldstat", 0, 2, { { Int, 0 }, { Ptr, 1 }}},
133 	{ "kldfirstmod", 0, 1, { { Int, 0 }}},
134 	{ 0, 0, 0, { { 0, 0 }}},
135 };
136 
137 /*
138  * If/when the list gets big, it might be desirable to do it
139  * as a hash table or binary search.
140  */
141 
142 struct syscall *
143 get_syscall(const char *name) {
144 	struct syscall *sc = syscalls;
145 
146 	while (sc->name) {
147 		if (!strcmp(name, sc->name))
148 			return sc;
149 		sc++;
150 	}
151 	return NULL;
152 }
153 
154 /*
155  * get_struct
156  *
157  * Copy a fixed amount of bytes from the process.
158  */
159 
160 static int
161 get_struct(int procfd, void *offset, void *buf, int len) {
162 	char *pos;
163 	FILE *p;
164 	int c, fd;
165 
166 	if ((fd = dup(procfd)) == -1)
167 		err(1, "dup");
168 	if ((p = fdopen(fd, "r")) == NULL)
169 		err(1, "fdopen");
170 	fseeko(p, (uintptr_t)offset, SEEK_SET);
171 	for (pos = (char *)buf; len--; pos++) {
172 		if ((c = fgetc(p)) == EOF)
173 			return -1;
174 		*pos = c;
175 	}
176 	fclose(p);
177 	return 0;
178 }
179 
180 /*
181  * get_string
182  * Copy a string from the process.  Note that it is
183  * expected to be a C string, but if max is set, it will
184  * only get that much.
185  */
186 
187 char *
188 get_string(int procfd, void *offset, int max) {
189 	char *buf;
190 	int size, len, c, fd;
191 	FILE *p;
192 
193 	if ((fd = dup(procfd)) == -1)
194 		err(1, "dup");
195 	if ((p = fdopen(fd, "r")) == NULL)
196 		err(1, "fdopen");
197 	buf = malloc( size = (max ? max : 64 ) );
198 	len = 0;
199 	buf[0] = 0;
200 	fseeko(p, (uintptr_t)offset, SEEK_SET);
201 	while ((c = fgetc(p)) != EOF) {
202 		buf[len++] = c;
203 		if (c == 0 || len == max) {
204 			buf[len] = 0;
205 			break;
206 		}
207 		if (len == size) {
208 			char *tmp;
209 			tmp = realloc(buf, size+64);
210 			if (tmp == NULL) {
211 				buf[len] = 0;
212 				fclose(p);
213 				return buf;
214 			}
215 			size += 64;
216 			buf = tmp;
217 		}
218 	}
219 	fclose(p);
220 	return buf;
221 }
222 
223 
224 /*
225  * Gag.  This is really unportable.  Multiplication is more portable.
226  * But slower, from the code I saw.
227  */
228 
229 static long long
230 make_quad(unsigned long p1, unsigned long p2) {
231   union {
232     long long ll;
233     unsigned long l[2];
234   } t;
235   t.l[0] = p1;
236   t.l[1] = p2;
237   return t.ll;
238 }
239 
240 
241 /*
242  * print_arg
243  * Converts a syscall argument into a string.  Said string is
244  * allocated via malloc(), so needs to be free()'d.  The file
245  * descriptor is for the process' memory (via /proc), and is used
246  * to get any data (where the argument is a pointer).  sc is
247  * a pointer to the syscall description (see above); args is
248  * an array of all of the system call arguments.
249  */
250 
251 char *
252 print_arg(int fd, struct syscall_args *sc, unsigned long *args) {
253   char *tmp = NULL;
254   switch (sc->type & ARG_MASK) {
255   case Hex:
256     tmp = malloc(12);
257     sprintf(tmp, "0x%lx", args[sc->offset]);
258     break;
259   case Octal:
260     tmp = malloc(13);
261     sprintf(tmp, "0%lo", args[sc->offset]);
262     break;
263   case Int:
264     tmp = malloc(12);
265     sprintf(tmp, "%ld", args[sc->offset]);
266     break;
267   case String:
268     {
269       char *tmp2;
270       tmp2 = get_string(fd, (void*)args[sc->offset], 0);
271       tmp = malloc(strlen(tmp2) + 3);
272       sprintf(tmp, "\"%s\"", tmp2);
273       free(tmp2);
274     }
275   break;
276   case StringArray:
277     {
278       int num, size, i;
279       char *tmp2;
280       char *string;
281       char *strarray[100];	/* XXX This is ugly. */
282 
283       if (get_struct(fd, (void *)args[sc->offset], (void *)&strarray,
284                      sizeof(strarray)) == -1) {
285 	err(1, "get_struct %p", (void *)args[sc->offset]);
286       }
287       num = 0;
288       size = 0;
289 
290       /* Find out how large of a buffer we'll need. */
291       while (strarray[num] != NULL) {
292 	string = get_string(fd, (void*)strarray[num], 0);
293         size += strlen(string);
294 	free(string);
295 	num++;
296       }
297       size += 4 + (num * 4);
298       tmp = (char *)malloc(size);
299       tmp2 = tmp;
300 
301       tmp2 += sprintf(tmp2, " [");
302       for (i = 0; i < num; i++) {
303 	string = get_string(fd, (void*)strarray[i], 0);
304         tmp2 += sprintf(tmp2, " \"%s\"%c", string, (i+1 == num) ? ' ' : ',');
305 	free(string);
306       }
307       tmp2 += sprintf(tmp2, "]");
308     }
309   break;
310   case Quad:
311     {
312       unsigned long long t;
313       unsigned long l1, l2;
314       l1 = args[sc->offset];
315       l2 = args[sc->offset+1];
316       t = make_quad(l1, l2);
317       tmp = malloc(24);
318       sprintf(tmp, "0x%qx", t);
319       break;
320     }
321   case Ptr:
322     tmp = malloc(12);
323     sprintf(tmp, "0x%lx", args[sc->offset]);
324     break;
325   case Ioctl:
326     {
327       const char *temp = ioctlname(args[sc->offset]);
328       if (temp)
329 	tmp = strdup(temp);
330       else {
331 	tmp = malloc(12);
332 	sprintf(tmp, "0x%lx", args[sc->offset]);
333       }
334     }
335     break;
336   case Signal:
337     {
338       long sig;
339 
340       sig = args[sc->offset];
341       tmp = malloc(12);
342       if (sig > 0 && sig < NSIG) {
343 	int i;
344 	sprintf(tmp, "sig%s", sys_signame[sig]);
345 	for (i = 0; tmp[i] != '\0'; ++i)
346 	  tmp[i] = toupper(tmp[i]);
347       } else {
348         sprintf(tmp, "%ld", sig);
349       }
350     }
351     break;
352   case Sockaddr:
353     {
354       struct sockaddr_storage ss;
355       char addr[64];
356       struct sockaddr_in *lsin;
357       struct sockaddr_in6 *lsin6;
358       struct sockaddr_un *sun;
359       struct sockaddr *sa;
360       char *p;
361       u_char *q;
362       int i;
363 
364       /* yuck: get ss_len */
365       if (get_struct(fd, (void *)args[sc->offset], (void *)&ss,
366 	sizeof(ss.ss_len) + sizeof(ss.ss_family)) == -1)
367 	err(1, "get_struct %p", (void *)args[sc->offset]);
368       /* sockaddr_un never have the length filled in! */
369       if (ss.ss_family == AF_UNIX) {
370 	if (get_struct(fd, (void *)args[sc->offset], (void *)&ss,
371 	  sizeof(*sun))
372 	  == -1)
373 	  err(2, "get_struct %p", (void *)args[sc->offset]);
374       } else {
375 	if (get_struct(fd, (void *)args[sc->offset], (void *)&ss, ss.ss_len)
376 	  == -1)
377 	  err(2, "get_struct %p", (void *)args[sc->offset]);
378       }
379 
380       switch (ss.ss_family) {
381       case AF_INET:
382 	lsin = (struct sockaddr_in *)&ss;
383 	inet_ntop(AF_INET, &lsin->sin_addr, addr, sizeof addr);
384 	asprintf(&tmp, "{ AF_INET %s:%d }", addr, htons(lsin->sin_port));
385 	break;
386       case AF_INET6:
387 	lsin6 = (struct sockaddr_in6 *)&ss;
388 	inet_ntop(AF_INET6, &lsin6->sin6_addr, addr, sizeof addr);
389 	asprintf(&tmp, "{ AF_INET6 [%s]:%d }", addr, htons(lsin6->sin6_port));
390 	break;
391       case AF_UNIX:
392         sun = (struct sockaddr_un *)&ss;
393         asprintf(&tmp, "{ AF_UNIX \"%s\" }", sun->sun_path);
394 	break;
395       default:
396 	sa = (struct sockaddr *)&ss;
397         asprintf(&tmp, "{ sa_len = %d, sa_family = %d, sa_data = {%n%*s } }",
398 	  (int)sa->sa_len, (int)sa->sa_family, &i,
399 	  6 * (int)(sa->sa_len - ((char *)&sa->sa_data - (char *)sa)), "");
400 	if (tmp != NULL) {
401 	  p = tmp + i;
402           for (q = (u_char *)&sa->sa_data; q < (u_char *)sa + sa->sa_len; q++)
403             p += sprintf(p, " %#02x,", *q);
404 	}
405       }
406     }
407     break;
408   }
409   return tmp;
410 }
411 
412 #define timespecsubt(tvp, uvp, vvp)					\
413 	do {								\
414 		(vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;		\
415 		(vvp)->tv_nsec = (tvp)->tv_nsec - (uvp)->tv_nsec;	\
416 		if ((vvp)->tv_nsec < 0) {				\
417 			(vvp)->tv_sec--;				\
418 			(vvp)->tv_nsec += 1000000000;			\
419 		}							\
420 	} while (0)
421 
422 /*
423  * print_syscall
424  * Print (to outfile) the system call and its arguments.  Note that
425  * nargs is the number of arguments (not the number of words; this is
426  * potentially confusing, I know).
427  */
428 
429 void
430 print_syscall(struct trussinfo *trussinfo, const char *name, int nargs, char **s_args) {
431   int i;
432   int len = 0;
433   struct timespec timediff;
434 
435   if (trussinfo->flags & FOLLOWFORKS)
436     len += fprintf(trussinfo->outfile, "%5d: ", trussinfo->pid);
437 
438   if (name != NULL && (!strcmp(name, "execve") || !strcmp(name, "exit"))) {
439     clock_gettime(CLOCK_REALTIME, &trussinfo->after);
440   }
441 
442   if (trussinfo->flags & ABSOLUTETIMESTAMPS) {
443     timespecsubt(&trussinfo->after, &trussinfo->start_time, &timediff);
444     len += fprintf(trussinfo->outfile, "%ld.%09ld ",
445 		   (long)timediff.tv_sec, timediff.tv_nsec);
446   }
447 
448   if (trussinfo->flags & RELATIVETIMESTAMPS) {
449     timespecsubt(&trussinfo->after, &trussinfo->before, &timediff);
450     len += fprintf(trussinfo->outfile, "%ld.%09ld ",
451 		   (long)timediff.tv_sec, timediff.tv_nsec);
452   }
453 
454   len += fprintf(trussinfo->outfile, "%s(", name);
455 
456   for (i = 0; i < nargs; i++) {
457     if (s_args[i])
458       len += fprintf(trussinfo->outfile, "%s", s_args[i]);
459     else
460       len += fprintf(trussinfo->outfile, "<missing argument>");
461     len += fprintf(trussinfo->outfile, "%s", i < (nargs - 1) ? "," : "");
462   }
463   len += fprintf(trussinfo->outfile, ")");
464   for (i = 0; i < 6 - (len / 8); i++)
465 	fprintf(trussinfo->outfile, "\t");
466 }
467 
468 void
469 print_syscall_ret(struct trussinfo *trussinfo, const char *name, int nargs, char **s_args, int errorp, int retval) {
470   print_syscall(trussinfo, name, nargs, s_args);
471   if (errorp) {
472     fprintf(trussinfo->outfile, " ERR#%d '%s'\n", retval, strerror(retval));
473   } else {
474     fprintf(trussinfo->outfile, " = %d (0x%x)\n", retval, retval);
475   }
476 }
477