lib/kafs/afssys.c

   1 /*
   2  * Copyright (c) 1995 - 2000, 2002, 2004, 2005 Kungliga Tekniska Högskolan
   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
  36 RCSID("$Id$");
  37
  38 struct procdata {
  39     unsigned long param4;
  40     unsigned long param3;
  41     unsigned long param2;
  42     unsigned long param1;
  43     unsigned long syscall;
  44 };
  45 #define VIOC_SYSCALL_PROC _IOW('C', 1, void *)
  46
  47 struct devdata {
  48     unsigned long syscall;
  49     unsigned long param1;
  50     unsigned long param2;
  51     unsigned long param3;
  52     unsigned long param4;
  53     unsigned long param5;
  54     unsigned long param6;
  55     unsigned long retval;
  56 };
  57 #ifdef _IOWR
  58 #define VIOC_SYSCALL_DEV _IOWR('C', 2, struct devdata)
  59 #define VIOC_SYSCALL_DEV_OPENAFS _IOWR('C', 1, struct devdata)
  60 #endif
  61
  62
  63 int _kafs_debug; /* this should be done in a better way */
  64
  65 #define UNKNOWN_ENTRY_POINT     (-1)
  66 #define NO_ENTRY_POINT          0
  67 #define SINGLE_ENTRY_POINT      1
  68 #define MULTIPLE_ENTRY_POINT    2
  69 #define SINGLE_ENTRY_POINT2     3
  70 #define SINGLE_ENTRY_POINT3     4
  71 #define LINUX_PROC_POINT        5
  72 #define AIX_ENTRY_POINTS        6
  73 #define MACOS_DEV_POINT         7
  74
  75 static int afs_entry_point = UNKNOWN_ENTRY_POINT;
  76 static int afs_syscalls[2];
  77 static char *afs_ioctlpath;
  78 static unsigned long afs_ioctlnum;
  79
  80 /* Magic to get AIX syscalls to work */
  81 #ifdef _AIX
  82
  83 static int (*Pioctl)(char*, int, struct ViceIoctl*, int);
  84 static int (*Setpag)(void);
  85
  86 #include "dlfcn.h"
  87
  88 /*
  89  *
  90  */
  91
  92 static int
  93 try_aix(void)
  94 {
  95 #ifdef STATIC_AFS_SYSCALLS
  96     Pioctl = aix_pioctl;
  97     Setpag = aix_setpag;
  98 #else
  99     void *ptr;
 100     char path[MaxPathLen], *p;
 101     /*
 102      * If we are root or running setuid don't trust AFSLIBPATH!
 103      */
 104     if (getuid() != 0 && !issuid() && (p = getenv("AFSLIBPATH")) != NULL)
 105         strlcpy(path, p, sizeof(path));
 106     else
 107         snprintf(path, sizeof(path), "%s/afslib.so", LIBDIR);
 108
 109     ptr = dlopen(path, RTLD_NOW);
 110     if(ptr == NULL) {
 111         if(_kafs_debug) {
 112             if(errno == ENOEXEC && (p = dlerror()) != NULL)
 113                 fprintf(stderr, "dlopen(%s): %s\n", path, p);
 114             else if (errno != ENOENT)
 115                 fprintf(stderr, "dlopen(%s): %s\n", path, strerror(errno));
 116         }
 117         return 1;
 118     }
 119     Setpag = (int (*)(void))dlsym(ptr, "aix_setpag");
 120     Pioctl = (int (*)(char*, int,
 121                       struct ViceIoctl*, int))dlsym(ptr, "aix_pioctl");
 122 #endif
 123     afs_entry_point = AIX_ENTRY_POINTS;
 124     return 0;
 125 }
 126 #endif /* _AIX */
 127
 128 /*
 129  * This probably only works under Solaris and could get confused if
 130  * there's a /etc/name_to_sysnum file.
 131  */
 132
 133 #if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
 134
 135 #define _PATH_ETC_NAME_TO_SYSNUM "/etc/name_to_sysnum"
 136
 137 static int
 138 map_syscall_name_to_number (const char *str, int *res)
 139 {
 140     FILE *f;
 141     char buf[256];
 142     size_t str_len = strlen (str);
 143
 144     f = fopen (_PATH_ETC_NAME_TO_SYSNUM, "r");
 145     if (f == NULL)
 146         return -1;
 147     while (fgets (buf, sizeof(buf), f) != NULL) {
 148         if (buf[0] == '#')
 149             continue;
 150
 151         if (strncmp (str, buf, str_len) == 0) {
 152             char *begptr = buf + str_len;
 153             char *endptr;
 154             long val = strtol (begptr, &endptr, 0);
 155
 156             if (val != 0 && endptr != begptr) {
 157                 fclose (f);
 158                 *res = val;
 159                 return 0;
 160             }
 161         }
 162     }
 163     fclose (f);
 164     return -1;
 165 }
 166 #endif
 167
 168 static int
 169 try_ioctlpath(const char *path, unsigned long ioctlnum, int entrypoint)
 170 {
 171     int fd, ret, saved_errno;
 172
 173     fd = open(path, O_RDWR);
 174     if (fd < 0)
 175         return 1;
 176     switch (entrypoint) {
 177     case LINUX_PROC_POINT: {
 178         struct procdata data = { 0, 0, 0, 0, AFSCALL_PIOCTL };
 179         data.param2 = (unsigned long)VIOCGETTOK;
 180         ret = ioctl(fd, ioctlnum, &data);
 181         break;
 182     }
 183     case MACOS_DEV_POINT: {
 184         struct devdata data = { AFSCALL_PIOCTL, 0, 0, 0, 0, 0, 0, 0 };
 185         data.param2 = (unsigned long)VIOCGETTOK;
 186         ret = ioctl(fd, ioctlnum, &data);
 187         break;
 188     }
 189     default:
 190         abort();
 191     }
 192     saved_errno = errno;
 193     close(fd);
 194     /*
 195      * Be quite liberal in what error are ok, the first is the one
 196      * that should trigger given that params is NULL.
 197      */
 198     if (ret &&
 199         (saved_errno != EFAULT &&
 200          saved_errno != EDOM &&
 201          saved_errno != ENOTCONN))
 202         return 1;
 203     afs_ioctlnum = ioctlnum;
 204     afs_ioctlpath = strdup(path);
 205     if (afs_ioctlpath == NULL)
 206         return 1;
 207     afs_entry_point = entrypoint;
 208     return 0;
 209 }
 210
 211 static int
 212 do_ioctl(void *data)
 213 {
 214     int fd, ret, saved_errno;
 215     fd = open(afs_ioctlpath, O_RDWR);
 216     if (fd < 0) {
 217         errno = EINVAL;
 218         return -1;
 219     }
 220     ret = ioctl(fd, afs_ioctlnum, data);
 221     saved_errno = errno;
 222     close(fd);
 223     errno = saved_errno;
 224     return ret;
 225 }
 226
 227 int
 228 k_pioctl(char *a_path,
 229          int o_opcode,
 230          struct ViceIoctl *a_paramsP,
 231          int a_followSymlinks)
 232 {
 233 #ifndef NO_AFS
 234     switch(afs_entry_point){
 235 #if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
 236     case SINGLE_ENTRY_POINT:
 237     case SINGLE_ENTRY_POINT2:
 238     case SINGLE_ENTRY_POINT3:
 239         return syscall(afs_syscalls[0], AFSCALL_PIOCTL,
 240                        a_path, o_opcode, a_paramsP, a_followSymlinks);
 241 #endif
 242 #if defined(AFS_PIOCTL)
 243     case MULTIPLE_ENTRY_POINT:
 244         return syscall(afs_syscalls[0],
 245                        a_path, o_opcode, a_paramsP, a_followSymlinks);
 246 #endif
 247     case LINUX_PROC_POINT: {
 248         struct procdata data = { 0, 0, 0, 0, AFSCALL_PIOCTL };
 249         data.param1 = (unsigned long)a_path;
 250         data.param2 = (unsigned long)o_opcode;
 251         data.param3 = (unsigned long)a_paramsP;
 252         data.param4 = (unsigned long)a_followSymlinks;
 253         return do_ioctl(&data);
 254     }
 255     case MACOS_DEV_POINT: {
 256         struct devdata data = { AFSCALL_PIOCTL, 0, 0, 0, 0, 0, 0, 0 };
 257         int ret;
 258
 259         data.param1 = (unsigned long)a_path;
 260         data.param2 = (unsigned long)o_opcode;
 261         data.param3 = (unsigned long)a_paramsP;
 262         data.param4 = (unsigned long)a_followSymlinks;
 263
 264         ret = do_ioctl(&data);
 265         if (ret)
 266             return ret;
 267
 268         return data.retval;
 269     }
 270 #ifdef _AIX
 271     case AIX_ENTRY_POINTS:
 272         return Pioctl(a_path, o_opcode, a_paramsP, a_followSymlinks);
 273 #endif
 274     }
 275     errno = ENOSYS;
 276 #ifdef SIGSYS
 277     kill(getpid(), SIGSYS);     /* You lose! */
 278 #endif
 279 #endif /* NO_AFS */
 280     return -1;
 281 }
 282
 283 int
 284 k_afs_cell_of_file(const char *path, char *cell, int len)
 285 {
 286     struct ViceIoctl parms;
 287     parms.in = NULL;
 288     parms.in_size = 0;
 289     parms.out = cell;
 290     parms.out_size = len;
 291     return k_pioctl(rk_UNCONST(path), VIOC_FILE_CELL_NAME, &parms, 1);
 292 }
 293
 294 int
 295 k_unlog(void)
 296 {
 297     struct ViceIoctl parms;
 298     memset(&parms, 0, sizeof(parms));
 299     return k_pioctl(0, VIOCUNLOG, &parms, 0);
 300 }
 301
 302 int
 303 k_setpag(void)
 304 {
 305 #ifndef NO_AFS
 306     switch(afs_entry_point){
 307 #if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
 308     case SINGLE_ENTRY_POINT:
 309     case SINGLE_ENTRY_POINT2:
 310     case SINGLE_ENTRY_POINT3:
 311         return syscall(afs_syscalls[0], AFSCALL_SETPAG);
 312 #endif
 313 #if defined(AFS_PIOCTL)
 314     case MULTIPLE_ENTRY_POINT:
 315         return syscall(afs_syscalls[1]);
 316 #endif
 317     case LINUX_PROC_POINT: {
 318         struct procdata data = { 0, 0, 0, 0, AFSCALL_SETPAG };
 319         return do_ioctl(&data);
 320     }
 321     case MACOS_DEV_POINT: {
 322         struct devdata data = { AFSCALL_SETPAG, 0, 0, 0, 0, 0, 0, 0 };
 323         int ret = do_ioctl(&data);
 324         if (ret)
 325             return ret;
 326         return data.retval;
 327      }
 328 #ifdef _AIX
 329     case AIX_ENTRY_POINTS:
 330         return Setpag();
 331 #endif
 332     }
 333
 334     errno = ENOSYS;
 335 #ifdef SIGSYS
 336     kill(getpid(), SIGSYS);     /* You lose! */
 337 #endif
 338 #endif /* NO_AFS */
 339     return -1;
 340 }
 341
 342 static jmp_buf catch_SIGSYS;
 343
 344 #ifdef SIGSYS
 345
 346 static RETSIGTYPE
 347 SIGSYS_handler(int sig)
 348 {
 349     errno = 0;
 350     signal(SIGSYS, SIGSYS_handler); /* Need to reinstall handler on SYSV */
 351     longjmp(catch_SIGSYS, 1);
 352 }
 353
 354 #endif
 355
 356 /*
 357  * Try to see if `syscall' is a pioctl.  Return 0 iff succesful.
 358  */
 359
 360 #if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
 361 static int
 362 try_one (int syscall_num)
 363 {
 364     struct ViceIoctl parms;
 365     memset(&parms, 0, sizeof(parms));
 366
 367     if (setjmp(catch_SIGSYS) == 0) {
 368         syscall(syscall_num, AFSCALL_PIOCTL,
 369                 0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
 370         if (errno == EINVAL) {
 371             afs_entry_point = SINGLE_ENTRY_POINT;
 372             afs_syscalls[0] = syscall_num;
 373             return 0;
 374         }
 375     }
 376     return 1;
 377 }
 378 #endif
 379
 380 /*
 381  * Try to see if `syscall_pioctl' is a pioctl syscall.  Return 0 iff
 382  * succesful.
 383  *
 384  */
 385
 386 #ifdef AFS_PIOCTL
 387 static int
 388 try_two (int syscall_pioctl, int syscall_setpag)
 389 {
 390     struct ViceIoctl parms;
 391     memset(&parms, 0, sizeof(parms));
 392
 393     if (setjmp(catch_SIGSYS) == 0) {
 394         syscall(syscall_pioctl,
 395                 0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
 396         if (errno == EINVAL) {
 397             afs_entry_point = MULTIPLE_ENTRY_POINT;
 398             afs_syscalls[0] = syscall_pioctl;
 399             afs_syscalls[1] = syscall_setpag;
 400             return 0;
 401         }
 402     }
 403     return 1;
 404 }
 405 #endif
 406
 407 int
 408 k_hasafs(void)
 409 {
 410 #if !defined(NO_AFS) && defined(SIGSYS)
 411     RETSIGTYPE (*saved_func)(int);
 412 #endif
 413     int saved_errno, ret;
 414     char *env = NULL;
 415
 416     if (!issuid())
 417         env = getenv ("AFS_SYSCALL");
 418
 419     /*
 420      * Already checked presence of AFS syscalls?
 421      */
 422     if (afs_entry_point != UNKNOWN_ENTRY_POINT)
 423         return afs_entry_point != NO_ENTRY_POINT;
 424
 425     /*
 426      * Probe kernel for AFS specific syscalls,
 427      * they (currently) come in two flavors.
 428      * If the syscall is absent we recive a SIGSYS.
 429      */
 430     afs_entry_point = NO_ENTRY_POINT;
 431
 432     saved_errno = errno;
 433 #ifndef NO_AFS
 434 #ifdef SIGSYS
 435     saved_func = signal(SIGSYS, SIGSYS_handler);
 436 #endif
 437     if (env && strstr(env, "..") == NULL) {
 438
 439         if (strncmp("/proc/", env, 6) == 0) {
 440             if (try_ioctlpath(env, VIOC_SYSCALL_PROC, LINUX_PROC_POINT) == 0)
 441                 goto done;
 442         }
 443         if (strncmp("/dev/", env, 5) == 0) {
 444 #ifdef VIOC_SYSCALL_DEV
 445             if (try_ioctlpath(env, VIOC_SYSCALL_DEV, MACOS_DEV_POINT) == 0)
 446                 goto done;
 447 #endif
 448 #ifdef VIOC_SYSCALL_DEV_OPENAFS
 449             if (try_ioctlpath(env,VIOC_SYSCALL_DEV_OPENAFS,MACOS_DEV_POINT) ==0)
 450                 goto done;
 451 #endif
 452         }
 453     }
 454
 455     ret = try_ioctlpath("/proc/fs/openafs/afs_ioctl",
 456                         VIOC_SYSCALL_PROC, LINUX_PROC_POINT);
 457     if (ret == 0)
 458         goto done;
 459     ret = try_ioctlpath("/proc/fs/nnpfs/afs_ioctl",
 460                         VIOC_SYSCALL_PROC, LINUX_PROC_POINT);
 461     if (ret == 0)
 462         goto done;
 463
 464 #ifdef VIOC_SYSCALL_DEV_OPENAFS
 465     ret = try_ioctlpath("/dev/openafs_ioctl",
 466                         VIOC_SYSCALL_DEV_OPENAFS, MACOS_DEV_POINT);
 467     if (ret == 0)
 468         goto done;
 469 #endif
 470 #ifdef VIOC_SYSCALL_DEV
 471     ret = try_ioctlpath("/dev/nnpfs_ioctl", VIOC_SYSCALL_DEV, MACOS_DEV_POINT);
 472     if (ret == 0)
 473         goto done;
 474 #endif
 475
 476 #if defined(AFS_SYSCALL) || defined(AFS_SYSCALL2) || defined(AFS_SYSCALL3)
 477     {
 478         int tmp;
 479
 480         if (env != NULL) {
 481             if (sscanf (env, "%d", &tmp) == 1) {
 482                 if (try_one (tmp) == 0)
 483                     goto done;
 484             } else {
 485                 char *end = NULL;
 486                 char *p;
 487                 char *s = strdup (env);
 488
 489                 if (s != NULL) {
 490                     for (p = strtok_r (s, ",", &end);
 491                          p != NULL;
 492                          p = strtok_r (NULL, ",", &end)) {
 493                         if (map_syscall_name_to_number (p, &tmp) == 0)
 494                             if (try_one (tmp) == 0) {
 495                                 free (s);
 496                                 goto done;
 497                             }
 498                     }
 499                     free (s);
 500                 }
 501             }
 502         }
 503     }
 504 #endif /* AFS_SYSCALL || AFS_SYSCALL2 || AFS_SYSCALL3 */
 505
 506 #ifdef AFS_SYSCALL
 507     if (try_one (AFS_SYSCALL) == 0)
 508         goto done;
 509 #endif /* AFS_SYSCALL */
 510
 511 #ifdef AFS_PIOCTL
 512     {
 513         int tmp[2];
 514
 515         if (env != NULL && sscanf (env, "%d%d", &tmp[0], &tmp[1]) == 2)
 516             if (try_two (tmp[0], tmp[1]) == 2)
 517                 goto done;
 518     }
 519 #endif /* AFS_PIOCTL */
 520
 521 #ifdef AFS_PIOCTL
 522     if (try_two (AFS_PIOCTL, AFS_SETPAG) == 0)
 523         goto done;
 524 #endif /* AFS_PIOCTL */
 525
 526 #ifdef AFS_SYSCALL2
 527     if (try_one (AFS_SYSCALL2) == 0)
 528         goto done;
 529 #endif /* AFS_SYSCALL2 */
 530
 531 #ifdef AFS_SYSCALL3
 532     if (try_one (AFS_SYSCALL3) == 0)
 533         goto done;
 534 #endif /* AFS_SYSCALL3 */
 535
 536 #ifdef _AIX
 537 #if 0
 538     if (env != NULL) {
 539         char *pos = NULL;
 540         char *pioctl_name;
 541         char *setpag_name;
 542
 543         pioctl_name = strtok_r (env, ", \t", &pos);
 544         if (pioctl_name != NULL) {
 545             setpag_name = strtok_r (NULL, ", \t", &pos);
 546             if (setpag_name != NULL)
 547                 if (try_aix (pioctl_name, setpag_name) == 0)
 548                     goto done;
 549         }
 550     }
 551 #endif
 552
 553     if(try_aix() == 0)
 554         goto done;
 555 #endif
 556
 557
 558 done:
 559 #ifdef SIGSYS
 560     signal(SIGSYS, saved_func);
 561 #endif
 562 #endif /* NO_AFS */
 563     errno = saved_errno;
 564     return afs_entry_point != NO_ENTRY_POINT;
 565 }
 566
 567 int
 568 k_hasafs_recheck(void)
 569 {
 570     afs_entry_point = UNKNOWN_ENTRY_POINT;
 571     return k_hasafs();
 572 }