1/*
2 * Copyright (c) 1995 - 2000, 2002 Kungliga Tekniska H�gskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include "kafs_locl.h"
35
36RCSID("$Id: afssys.c,v 1.69 2003/03/18 04:18:45 lha Exp $");
37
38int _kafs_debug; /* this should be done in a better way */
39
40#define NO_ENTRY_POINT 0
41#define SINGLE_ENTRY_POINT 1
42#define MULTIPLE_ENTRY_POINT 2
43#define SINGLE_ENTRY_POINT2 3
44#define SINGLE_ENTRY_POINT3 4
45#define AIX_ENTRY_POINTS 5
46#define UNKNOWN_ENTRY_POINT 6
47static int afs_entry_point = UNKNOWN_ENTRY_POINT;
48static int afs_syscalls[2];
49
50/* Magic to get AIX syscalls to work */
51#ifdef _AIX
52
53static int (*Pioctl)(char*, int, struct ViceIoctl*, int);
54static int (*Setpag)(void);
55
56#include "dlfcn.h"
57
58/*
59 *
60 */
61
62static int
63try_aix(void)
64{
65#ifdef STATIC_AFS_SYSCALLS
66 Pioctl = aix_pioctl;
67 Setpag = aix_setpag;
68#else
69 void *ptr;
70 char path[MaxPathLen], *p;
71 /*
72 * If we are root or running setuid don't trust AFSLIBPATH!
73 */
74 if (getuid() != 0 && !issuid() && (p = getenv("AFSLIBPATH")) != NULL)
75 strlcpy(path, p, sizeof(path));
76 else
77 snprintf(path, sizeof(path), "%s/afslib.so", LIBDIR);
78
79 ptr = dlopen(path, RTLD_NOW);
80 if(ptr == NULL) {
81 if(_kafs_debug) {
82 if(errno == ENOEXEC && (p = dlerror()) != NULL)
83 fprintf(stderr, "dlopen(%s): %s\n", path, p);
84 else if (errno != ENOENT)
85 fprintf(stderr, "dlopen(%s): %s\n", path, strerror(errno));
86 }
87 return 1;
88 }
89 Setpag = (int (*)(void))dlsym(ptr, "aix_setpag");
90 Pioctl = (int (*)(char*, int,
91 struct ViceIoctl*, int))dlsym(ptr, "aix_pioctl");
92#endif
93 afs_entry_point = AIX_ENTRY_POINTS;
94 return 0;
95}
96#endif /* _AIX */
97
98/*
99 * This probably only works under Solaris and could get confused if
100 * there's a /etc/name_to_sysnum file.
101 */
102
103#define _PATH_ETC_NAME_TO_SYSNUM "/etc/name_to_sysnum"
104
105static int
106map_syscall_name_to_number (const char *str, int *res)
107{
108 FILE *f;
109 char buf[256];
110 size_t str_len = strlen (str);
111
112 f = fopen (_PATH_ETC_NAME_TO_SYSNUM, "r");
113 if (f == NULL)
114 return -1;
115 while (fgets (buf, sizeof(buf), f) != NULL) {
116 if (buf[0] == '#')
117 continue;
118
119 if (strncmp (str, buf, str_len) == 0) {
120 char *begptr = buf + str_len;
121 char *endptr;
122 long val = strtol (begptr, &endptr, 0);
123
124 if (val != 0 && endptr != begptr) {
125 fclose (f);
126 *res = val;
127 return 0;
128 }
129 }
130 }
131 fclose (f);
132 return -1;
133}
134
135int
136k_pioctl(char *a_path,
137 int o_opcode,
138 struct ViceIoctl *a_paramsP,
139 int a_followSymlinks)
140{
141#ifndef NO_AFS
142 switch(afs_entry_point){
143#if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
144 case SINGLE_ENTRY_POINT:
145 case SINGLE_ENTRY_POINT2:
146 case SINGLE_ENTRY_POINT3:
147 return syscall(afs_syscalls[0], AFSCALL_PIOCTL,
148 a_path, o_opcode, a_paramsP, a_followSymlinks);
149#endif
150#if defined(AFS_PIOCTL)
151 case MULTIPLE_ENTRY_POINT:
152 return syscall(afs_syscalls[0],
153 a_path, o_opcode, a_paramsP, a_followSymlinks);
154#endif
155#ifdef _AIX
156 case AIX_ENTRY_POINTS:
157 return Pioctl(a_path, o_opcode, a_paramsP, a_followSymlinks);
158#endif
159 }
160
161 errno = ENOSYS;
162#ifdef SIGSYS
163 kill(getpid(), SIGSYS); /* You lose! */
164#endif
165#endif /* NO_AFS */
166 return -1;
167}
168
169int
170k_afs_cell_of_file(const char *path, char *cell, int len)
171{
172 struct ViceIoctl parms;
173 parms.in = NULL;
174 parms.in_size = 0;
175 parms.out = cell;
176 parms.out_size = len;
177 return k_pioctl((char*)path, VIOC_FILE_CELL_NAME, &parms, 1);
178}
179
180int
181k_unlog(void)
182{
183 struct ViceIoctl parms;
184 memset(&parms, 0, sizeof(parms));
185 return k_pioctl(0, VIOCUNLOG, &parms, 0);
186}
187
188int
189k_setpag(void)
190{
191#ifndef NO_AFS
192 switch(afs_entry_point){
193#if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
194 case SINGLE_ENTRY_POINT:
195 case SINGLE_ENTRY_POINT2:
196 case SINGLE_ENTRY_POINT3:
197 return syscall(afs_syscalls[0], AFSCALL_SETPAG);
198#endif
199#if defined(AFS_PIOCTL)
200 case MULTIPLE_ENTRY_POINT:
201 return syscall(afs_syscalls[1]);
202#endif
203#ifdef _AIX
204 case AIX_ENTRY_POINTS:
205 return Setpag();
206#endif
207 }
208
209 errno = ENOSYS;
210#ifdef SIGSYS
211 kill(getpid(), SIGSYS); /* You lose! */
212#endif
213#endif /* NO_AFS */
214 return -1;
215}
216
217static jmp_buf catch_SIGSYS;
218
219#ifdef SIGSYS
220
221static RETSIGTYPE
222SIGSYS_handler(int sig)
223{
224 errno = 0;
225 signal(SIGSYS, SIGSYS_handler); /* Need to reinstall handler on SYSV */
226 longjmp(catch_SIGSYS, 1);
227}
228
229#endif
230
231/*
232 * Try to see if `syscall' is a pioctl. Return 0 iff succesful.
233 */
234
235#if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
236static int
237try_one (int syscall_num)
238{
239 struct ViceIoctl parms;
240 memset(&parms, 0, sizeof(parms));
241
242 if (setjmp(catch_SIGSYS) == 0) {
243 syscall(syscall_num, AFSCALL_PIOCTL,
244 0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
245 if (errno == EINVAL) {
246 afs_entry_point = SINGLE_ENTRY_POINT;
247 afs_syscalls[0] = syscall_num;
248 return 0;
249 }
250 }
251 return 1;
252}
253#endif
254
255/*
256 * Try to see if `syscall_pioctl' is a pioctl syscall. Return 0 iff
257 * succesful.
258 *
259 */
260
261#ifdef AFS_PIOCTL
262static int
263try_two (int syscall_pioctl, int syscall_setpag)
264{
265 struct ViceIoctl parms;
266 memset(&parms, 0, sizeof(parms));
267
268 if (setjmp(catch_SIGSYS) == 0) {
269 syscall(syscall_pioctl,
270 0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
271 if (errno == EINVAL) {
272 afs_entry_point = MULTIPLE_ENTRY_POINT;
273 afs_syscalls[0] = syscall_pioctl;
274 afs_syscalls[1] = syscall_setpag;
275 return 0;
276 }
277 }
278 return 1;
279}
280#endif
281
282int
283k_hasafs(void)
284{
285#if !defined(NO_AFS) && defined(SIGSYS)
286 RETSIGTYPE (*saved_func)(int);
287#endif
288 int saved_errno;
289 char *env = getenv ("AFS_SYSCALL");
290
291 /*
292 * Already checked presence of AFS syscalls?
293 */
294 if (afs_entry_point != UNKNOWN_ENTRY_POINT)
295 return afs_entry_point != NO_ENTRY_POINT;
296
297 /*
298 * Probe kernel for AFS specific syscalls,
299 * they (currently) come in two flavors.
300 * If the syscall is absent we recive a SIGSYS.
301 */
302 afs_entry_point = NO_ENTRY_POINT;
303
304 saved_errno = errno;
305#ifndef NO_AFS
306#ifdef SIGSYS
307 saved_func = signal(SIGSYS, SIGSYS_handler);
308#endif
309
310#if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
311 {
312 int tmp;
313
314 if (env != NULL) {
315 if (sscanf (env, "%d", &tmp) == 1) {
316 if (try_one (tmp) == 0)
317 goto done;
318 } else {
319 char *end = NULL;
320 char *p;
321 char *s = strdup (env);
322
323 if (s != NULL) {
324 for (p = strtok_r (s, ",", &end);
325 p != NULL;
326 p = strtok_r (NULL, ",", &end)) {
327 if (map_syscall_name_to_number (p, &tmp) == 0)
328 if (try_one (tmp) == 0) {
329 free (s);
330 goto done;
331 }
332 }
333 free (s);
334 }
335 }
336 }
337 }
338#endif /* AFS_SYSCALL || AFS_SYSCALL2 || AFS_SYSCALL3 */
339
340#ifdef AFS_SYSCALL
341 if (try_one (AFS_SYSCALL) == 0)
342 goto done;
343#endif /* AFS_SYSCALL */
344
345#ifdef AFS_PIOCTL
346 {
347 int tmp[2];
348
349 if (env != NULL && sscanf (env, "%d%d", &tmp[0], &tmp[1]) == 2)
350 if (try_two (tmp[0], tmp[1]) == 2)
351 goto done;
352 }
353#endif /* AFS_PIOCTL */
354
355#ifdef AFS_PIOCTL
356 if (try_two (AFS_PIOCTL, AFS_SETPAG) == 0)
357 goto done;
358#endif /* AFS_PIOCTL */
359
360#ifdef AFS_SYSCALL2
361 if (try_one (AFS_SYSCALL2) == 0)
362 goto done;
363#endif /* AFS_SYSCALL2 */
364
365#ifdef AFS_SYSCALL3
366 if (try_one (AFS_SYSCALL3) == 0)
367 goto done;
368#endif /* AFS_SYSCALL3 */
369
370#ifdef _AIX
371#if 0
372 if (env != NULL) {
373 char *pos = NULL;
374 char *pioctl_name;
375 char *setpag_name;
376
377 pioctl_name = strtok_r (env, ", \t", &pos);
378 if (pioctl_name != NULL) {
379 setpag_name = strtok_r (NULL, ", \t", &pos);
380 if (setpag_name != NULL)
381 if (try_aix (pioctl_name, setpag_name) == 0)
382 goto done;
383 }
384 }
385#endif
386
387 if(try_aix() == 0)
388 goto done;
389#endif
390
391done:
392#ifdef SIGSYS
393 signal(SIGSYS, saved_func);
394#endif
395#endif /* NO_AFS */
396 errno = saved_errno;
397 return afs_entry_point != NO_ENTRY_POINT;
398}