syscalls.c revision 85292
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
33static const char rcsid[] =
34  "$FreeBSD: head/usr.bin/truss/syscalls.c 85292 2001-10-21 21:57:10Z des $";
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/un.h>
45#include <netinet/in.h>
46#include <arpa/inet.h>
47
48#include <err.h>
49#include <signal.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53#include <unistd.h>
54
55#include "syscall.h"
56
57/*
58 * This should probably be in its own file.
59 */
60
61struct syscall syscalls[] = {
62	{ "readlink", 1, 3,
63	  { { String, 0 } , { String | OUT, 1 }, { Int, 2 }}},
64	{ "lseek", 2, 3,
65	  { { Int, 0 }, {Quad, 2 }, { Int, 4 }}},
66	{ "mmap", 2, 6,
67	  { { Hex, 0 }, {Int, 1}, {Hex, 2}, {Hex, 3}, {Int, 4}, {Quad, 6}}},
68	{ "open", 1, 3,
69	  { { String | IN, 0} , { Int, 1}, {Octal, 2}}},
70	{ "linux_open", 1, 3,
71	  { { String, 0 }, { Int, 1}, { Octal, 2 }}},
72	{ "close", 1, 1, { { Int, 0 } } },
73	{ "fstat", 1, 2,
74	  { { Int, 0},  {Ptr | OUT , 1 }}},
75	{ "stat", 1, 2,
76	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
77	{ "lstat", 1, 2,
78	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
79	{ "linux_newstat", 1, 2,
80	  { { String | IN, 0 }, { Ptr | OUT, 1 }}},
81	{ "linux_newfstat", 1, 2,
82	  { { Int, 0 }, { Ptr | OUT, 1 }}},
83	{ "write", 1, 3,
84	  { { Int, 0}, { Ptr | IN, 1 }, { Int, 2 }}},
85	{ "ioctl", 1, 3,
86	  { { Int, 0}, { Ioctl, 1 }, { Hex, 2 }}},
87	{ "break", 1, 1, { { Hex, 0 }}},
88	{ "exit", 0, 1, { { Hex, 0 }}},
89	{ "access", 1, 2, { { String | IN, 0 }, { Int, 1 }}},
90	{ "sigaction", 1, 3,
91	  { { Signal, 0 }, { Ptr | IN, 1 }, { Ptr | OUT, 2 }}},
92	{ "accept", 1, 3,
93	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
94	{ "bind", 1, 3,
95	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
96	{ "connect", 1, 3,
97	  { { Hex, 0 }, { Sockaddr | IN, 1 }, { Int, 2 } } },
98	{ "getpeername", 1, 3,
99	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
100	{ "getsockname", 1, 3,
101	  { { Hex, 0 }, { Sockaddr | OUT, 1 }, { Ptr | OUT, 2 } } },
102	{ 0, 0, 0, { { 0, 0 }}},
103};
104
105char * ioctlname __P((int));
106
107/*
108 * If/when the list gets big, it might be desirable to do it
109 * as a hash table or binary search.
110 */
111
112struct syscall *
113get_syscall(const char *name) {
114	struct syscall *sc = syscalls;
115
116	while (sc->name) {
117		if (!strcmp(name, sc->name))
118			return sc;
119		sc++;
120	}
121	return NULL;
122}
123
124/*
125 * get_struct
126 *
127 * Copy a fixed amount of bytes from the process.
128 */
129
130int
131get_struct(int procfd, void *offset, void *buf, int len) {
132	char *pos;
133	FILE *p;
134	int c, fd;
135
136	if ((fd = dup(procfd)) == -1)
137		err(1, "dup");
138	if ((p = fdopen(fd, "r")) == NULL)
139		err(1, "fdopen");
140	fseek(p, (long)offset, SEEK_SET);
141	for (pos = (char *)buf; len--; pos++) {
142		if ((c = fgetc(p)) == EOF)
143			return -1;
144		*pos = c;
145	}
146	fclose(p);
147	return 0;
148}
149
150/*
151 * get_string
152 * Copy a string from the process.  Note that it is
153 * expected to be a C string, but if max is set, it will
154 * only get that much.
155 */
156
157char *
158get_string(int procfd, void *offset, int max) {
159	char *buf;
160	int size, len, c, fd;
161	FILE *p;
162
163	if ((fd = dup(procfd)) == -1)
164		err(1, "dup");
165	if ((p = fdopen(fd, "r")) == NULL)
166		err(1, "fdopen");
167	buf = malloc( size = (max ? max : 64 ) );
168	len = 0;
169	buf[0] = 0;
170	fseek(p, (long)offset, SEEK_SET);
171	while ((c = fgetc(p)) != EOF) {
172		buf[len++] = c;
173		if (c == 0 || len == max) {
174			buf[len] = 0;
175			break;
176		}
177		if (len == size) {
178			char *tmp;
179			tmp = realloc(buf, size+64);
180			if (tmp == NULL) {
181				buf[len] = 0;
182				fclose(p);
183				return buf;
184			}
185			size += 64;
186			buf = tmp;
187		}
188	}
189	fclose(p);
190	return buf;
191}
192
193
194/*
195 * Gag.  This is really unportable.  Multiplication is more portable.
196 * But slower, from the code I saw.
197 */
198
199static long long
200make_quad(unsigned long p1, unsigned long p2) {
201  union {
202    long long ll;
203    unsigned long l[2];
204  } t;
205  t.l[0] = p1;
206  t.l[1] = p2;
207  return t.ll;
208}
209
210
211/*
212 * print_arg
213 * Converts a syscall argument into a string.  Said string is
214 * allocated via malloc(), so needs to be free()'d.  The file
215 * descriptor is for the process' memory (via /proc), and is used
216 * to get any data (where the argument is a pointer).  sc is
217 * a pointer to the syscall description (see above); args is
218 * an array of all of the system call arguments.
219 */
220
221char *
222print_arg(int fd, struct syscall_args *sc, unsigned long *args) {
223  char *tmp = NULL;
224  switch (sc->type & ARG_MASK) {
225  case Hex:
226    tmp = malloc(12);
227    sprintf(tmp, "0x%lx", args[sc->offset]);
228    break;
229  case Octal:
230    tmp = malloc(13);
231    sprintf(tmp, "0%lo", args[sc->offset]);
232    break;
233  case Int:
234    tmp = malloc(12);
235    sprintf(tmp, "%ld", args[sc->offset]);
236    break;
237  case String:
238    {
239      char *tmp2;
240      tmp2 = get_string(fd, (void*)args[sc->offset], 0);
241      tmp = malloc(strlen(tmp2) + 3);
242      sprintf(tmp, "\"%s\"", tmp2);
243      free(tmp2);
244    }
245  break;
246  case Quad:
247    {
248      unsigned long long t;
249      unsigned long l1, l2;
250      l1 = args[sc->offset];
251      l2 = args[sc->offset+1];
252      t = make_quad(l1, l2);
253      tmp = malloc(24);
254      sprintf(tmp, "0x%qx", t);
255      break;
256    }
257  case Ptr:
258    tmp = malloc(12);
259    sprintf(tmp, "0x%lx", args[sc->offset]);
260    break;
261  case Ioctl:
262    {
263      char *temp = ioctlname(args[sc->offset]);
264      if (temp)
265	tmp = strdup(temp);
266      else {
267	tmp = malloc(12);
268	sprintf(tmp, "0x%lx", args[sc->offset]);
269      }
270    }
271    break;
272  case Signal:
273    {
274      long sig;
275
276      sig = args[sc->offset];
277      tmp = malloc(12);
278      if (sig > 0 && sig < NSIG) {
279	int i;
280	sprintf(tmp, "sig%s", sys_signame[sig]);
281	for (i = 0; tmp[i] != '\0'; ++i)
282	  tmp[i] = toupper(tmp[i]);
283      } else {
284        sprintf(tmp, "%ld", sig);
285      }
286    }
287    break;
288  case Sockaddr:
289    {
290      struct sockaddr *sa;
291      char addr[64];
292      u_char sa_len;
293      char *p, *q;
294      int i, len;
295
296      /* yuck: get sa_len */
297      get_struct(fd, (void *)args[sc->offset], (void *)&sa_len, sizeof sa_len);
298      sa = malloc(sa_len);
299      get_struct(fd, (void *)args[sc->offset], (void *)sa, sa_len);
300
301      tmp = malloc(100);
302      if (sa->sa_family == AF_INET) {
303	struct sockaddr_in *sin = (struct sockaddr_in *)sa;
304	inet_ntop(AF_INET, &sin->sin_addr, addr, sizeof addr);
305	sprintf(tmp, "{ AF_INET %s:%d }", addr, htons(sin->sin_port));
306      } else if (sa->sa_family == AF_INET6) {
307	struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sa;
308	inet_ntop(AF_INET6, &sin6->sin6_addr, addr, sizeof addr);
309	sprintf(tmp, "{ AF_INET6 [%s]:%d }", addr, htons(sin6->sin6_port));
310      } else if (sa->sa_family == AF_UNIX) {
311        struct sockaddr_un *sun = (struct sockaddr_un *)sa;
312        sprintf(tmp, "{ AF_UNIX \"%s\" }", sun->sun_path);
313      } else {
314        p = tmp;
315        p += sprintf(p, "{ sa_len = %d, sa_family = %d, sa_data = {",
316                sa->sa_len, sa->sa_family);
317        for (q = sa->sa_data; q < ((char *)sa) + sa_len; q++)
318          p += sprintf(p, " 0x%02x,", *q);
319        p--;
320        p += sprintf(p, "} }");
321      }
322      free(sa);
323    }
324    break;
325  }
326  return tmp;
327}
328
329/*
330 * print_syscall
331 * Print (to outfile) the system call and its arguments.  Note that
332 * nargs is the number of arguments (not the number of words; this is
333 * potentially confusing, I know).
334 */
335
336void
337print_syscall(FILE *outfile, const char *name, int nargs, char **s_args) {
338  int i;
339  int len = 0;
340  len += fprintf(outfile, "%s(", name);
341  for (i = 0; i < nargs; i++) {
342    if (s_args[i])
343      len += fprintf(outfile, "%s", s_args[i]);
344    else
345      len += fprintf(outfile, "<missing argument>");
346    len += fprintf(outfile, "%s", i < (nargs - 1) ? "," : "");
347  }
348  len += fprintf(outfile, ")");
349  for (i = 0; i < 6 - (len / 8); i++)
350	fprintf(outfile, "\t");
351}
352
353void
354print_syscall_ret(FILE *outfile, const char *name, int nargs, char **s_args, int errorp, int retval) {
355  print_syscall(outfile, name, nargs, s_args);
356  if (errorp) {
357    fprintf(outfile, " ERR#%d '%s'\n", retval, strerror(retval));
358  } else {
359    fprintf(outfile, " = %d (0x%x)\n", retval, retval);
360  }
361}
362