lib/uid_wrapper/uid_wrapper.c

   1 /*
   2  * Copyright (c) 2009      Andrew Tridgell
   3  * Copyright (c) 2011-2013 Andreas Schneider <asn@samba.org>
   4  *
   5  * This program is free software: you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation, either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include "config.h"
  20
  21 #include <errno.h>
  22 #include <stdarg.h>
  23 #include <stdbool.h>
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <sys/types.h>
  28 #include <unistd.h>
  29 #include <grp.h>
  30 #ifdef HAVE_SYS_SYSCALL_H
  31 #include <sys/syscall.h>
  32 #endif
  33 #ifdef HAVE_SYSCALL_H
  34 #include <syscall.h>
  35 #endif
  36 #include <dlfcn.h>
  37
  38 #include <pthread.h>
  39
  40 #ifdef HAVE_GCC_THREAD_LOCAL_STORAGE
  41 # define UWRAP_THREAD __thread
  42 #else
  43 # define UWRAP_THREAD
  44 #endif
  45
  46 # define UWRAP_LOCK(m) do { \
  47         pthread_mutex_lock(&( m ## _mutex)); \
  48 } while(0)
  49
  50 # define UWRAP_UNLOCK(m) do { \
  51         pthread_mutex_unlock(&( m ## _mutex)); \
  52 } while(0)
  53
  54 /* Add new global locks here please */
  55 # define UWRAP_LOCK_ALL \
  56         UWRAP_LOCK(uwrap_id); \
  57         UWRAP_LOCK(libc_symbol_binding); \
  58         UWRAP_LOCK(libpthread_symbol_binding)
  59
  60 # define UWRAP_UNLOCK_ALL \
  61         UWRAP_UNLOCK(libpthread_symbol_binding); \
  62         UWRAP_UNLOCK(libc_symbol_binding); \
  63         UWRAP_UNLOCK(uwrap_id)
  64
  65 #ifdef HAVE_CONSTRUCTOR_ATTRIBUTE
  66 #define CONSTRUCTOR_ATTRIBUTE __attribute__ ((constructor))
  67 #else
  68 #define CONSTRUCTOR_ATTRIBUTE
  69 #endif /* HAVE_CONSTRUCTOR_ATTRIBUTE */
  70
  71 #ifdef HAVE_DESTRUCTOR_ATTRIBUTE
  72 #define DESTRUCTOR_ATTRIBUTE __attribute__ ((destructor))
  73 #else
  74 #define DESTRUCTOR_ATTRIBUTE
  75 #endif /* HAVE_DESTRUCTOR_ATTRIBUTE */
  76
  77 #ifdef HAVE_ADDRESS_SANITIZER_ATTRIBUTE
  78 #define DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE __attribute__((no_sanitize_address))
  79 #else /* DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE */
  80 #define DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE
  81 #endif /* DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE */
  82
  83 /* GCC have printf type attribute check. */
  84 #ifdef HAVE_FUNCTION_ATTRIBUTE_FORMAT
  85 #define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b)))
  86 #else
  87 #define PRINTF_ATTRIBUTE(a,b)
  88 #endif /* HAVE_FUNCTION_ATTRIBUTE_FORMAT */
  89
  90 #define UWRAP_DLIST_ADD(list,item) do { \
  91         if (!(list)) { \
  92                 (item)->prev    = NULL; \
  93                 (item)->next    = NULL; \
  94                 (list)          = (item); \
  95         } else { \
  96                 (item)->prev    = NULL; \
  97                 (item)->next    = (list); \
  98                 (list)->prev    = (item); \
  99                 (list)          = (item); \
 100         } \
 101 } while (0)
 102
 103 #define UWRAP_DLIST_REMOVE(list,item) do { \
 104         if ((list) == (item)) { \
 105                 (list)          = (item)->next; \
 106                 if (list) { \
 107                         (list)->prev    = NULL; \
 108                 } \
 109         } else { \
 110                 if ((item)->prev) { \
 111                         (item)->prev->next      = (item)->next; \
 112                 } \
 113                 if ((item)->next) { \
 114                         (item)->next->prev      = (item)->prev; \
 115                 } \
 116         } \
 117         (item)->prev    = NULL; \
 118         (item)->next    = NULL; \
 119 } while (0)
 120
 121 #ifndef SAFE_FREE
 122 #define SAFE_FREE(x) do { if ((x) != NULL) {free(x); (x)=NULL;} } while(0)
 123 #endif
 124
 125 /*****************
 126  * LOGGING
 127  *****************/
 128
 129 enum uwrap_dbglvl_e {
 130         UWRAP_LOG_ERROR = 0,
 131         UWRAP_LOG_WARN,
 132         UWRAP_LOG_DEBUG,
 133         UWRAP_LOG_TRACE
 134 };
 135
 136 #ifdef NDEBUG
 137 # define UWRAP_LOG(...)
 138 #else /* NDEBUG */
 139 static void uwrap_log(enum uwrap_dbglvl_e dbglvl, const char *function, const char *format, ...) PRINTF_ATTRIBUTE(3, 4);
 140 # define UWRAP_LOG(dbglvl, ...) uwrap_log((dbglvl), __func__, __VA_ARGS__)
 141
 142 static void uwrap_log(enum uwrap_dbglvl_e dbglvl, const char *function, const char *format, ...)
 143 {
 144         char buffer[1024];
 145         va_list va;
 146         const char *d;
 147         unsigned int lvl = 0;
 148
 149         d = getenv("UID_WRAPPER_DEBUGLEVEL");
 150         if (d != NULL) {
 151                 lvl = atoi(d);
 152         }
 153
 154         va_start(va, format);
 155         vsnprintf(buffer, sizeof(buffer), format, va);
 156         va_end(va);
 157
 158         if (lvl >= dbglvl) {
 159                 const char *prefix;
 160                 switch (dbglvl) {
 161                         case UWRAP_LOG_ERROR:
 162                                 prefix = "UWRAP_ERROR";
 163                                 break;
 164                         case UWRAP_LOG_WARN:
 165                                 prefix = "UWRAP_WARN";
 166                                 break;
 167                         case UWRAP_LOG_DEBUG:
 168                                 prefix = "UWRAP_DEBUG";
 169                                 break;
 170                         case UWRAP_LOG_TRACE:
 171                                 prefix = "UWRAP_TRACE";
 172                                 break;
 173                 }
 174
 175                 fprintf(stderr,
 176                         "%s(%d) - %s: %s\n",
 177                         prefix,
 178                         (int)getpid(),
 179                         function,
 180                         buffer);
 181         }
 182 }
 183 #endif /* NDEBUG */
 184
 185 /*****************
 186  * LIBC
 187  *****************/
 188
 189 #define LIBC_NAME "libc.so"
 190
 191 typedef int (*__libc_setuid)(uid_t uid);
 192
 193 typedef uid_t (*__libc_getuid)(void);
 194
 195 #ifdef HAVE_SETEUID
 196 typedef int (*__libc_seteuid)(uid_t euid);
 197 #endif
 198
 199 #ifdef HAVE_SETREUID
 200 typedef int (*__libc_setreuid)(uid_t ruid, uid_t euid);
 201 #endif
 202
 203 #ifdef HAVE_SETRESUID
 204 typedef int (*__libc_setresuid)(uid_t ruid, uid_t euid, uid_t suid);
 205 #endif
 206
 207 #ifdef HAVE_GETRESUID
 208 typedef int (*__libc_getresuid)(uid_t *ruid, uid_t *euid, uid_t *suid);
 209 #endif
 210
 211 typedef uid_t (*__libc_geteuid)(void);
 212
 213 typedef int (*__libc_setgid)(gid_t gid);
 214
 215 typedef gid_t (*__libc_getgid)(void);
 216
 217 #ifdef HAVE_SETEGID
 218 typedef int (*__libc_setegid)(uid_t egid);
 219 #endif
 220
 221 #ifdef HAVE_SETREGID
 222 typedef int (*__libc_setregid)(uid_t rgid, uid_t egid);
 223 #endif
 224
 225 #ifdef HAVE_SETRESGID
 226 typedef int (*__libc_setresgid)(uid_t rgid, uid_t egid, uid_t sgid);
 227 #endif
 228
 229 #ifdef HAVE_GETRESGID
 230 typedef int (*__libc_getresgid)(gid_t *rgid, gid_t *egid, gid_t *sgid);
 231 #endif
 232
 233 typedef gid_t (*__libc_getegid)(void);
 234
 235 typedef int (*__libc_getgroups)(int size, gid_t list[]);
 236
 237 typedef int (*__libc_setgroups)(size_t size, const gid_t *list);
 238
 239 #ifdef HAVE_SYSCALL
 240 typedef long int (*__libc_syscall)(long int sysno, ...);
 241 #endif
 242
 243 #define UWRAP_SYMBOL_ENTRY(i) \
 244         union { \
 245                 __libc_##i f; \
 246                 void *obj; \
 247         } _libc_##i
 248
 249 struct uwrap_libc_symbols {
 250         UWRAP_SYMBOL_ENTRY(setuid);
 251         UWRAP_SYMBOL_ENTRY(getuid);
 252 #ifdef HAVE_SETEUID
 253         UWRAP_SYMBOL_ENTRY(seteuid);
 254 #endif
 255 #ifdef HAVE_SETREUID
 256         UWRAP_SYMBOL_ENTRY(setreuid);
 257 #endif
 258 #ifdef HAVE_SETRESUID
 259         UWRAP_SYMBOL_ENTRY(setresuid);
 260 #endif
 261 #ifdef HAVE_GETRESUID
 262         UWRAP_SYMBOL_ENTRY(getresuid);
 263 #endif
 264         UWRAP_SYMBOL_ENTRY(geteuid);
 265         UWRAP_SYMBOL_ENTRY(setgid);
 266         UWRAP_SYMBOL_ENTRY(getgid);
 267 #ifdef HAVE_SETEGID
 268         UWRAP_SYMBOL_ENTRY(setegid);
 269 #endif
 270 #ifdef HAVE_SETREGID
 271         UWRAP_SYMBOL_ENTRY(setregid);
 272 #endif
 273 #ifdef HAVE_SETRESGID
 274         UWRAP_SYMBOL_ENTRY(setresgid);
 275 #endif
 276 #ifdef HAVE_GETRESGID
 277         UWRAP_SYMBOL_ENTRY(getresgid);
 278 #endif
 279         UWRAP_SYMBOL_ENTRY(getegid);
 280         UWRAP_SYMBOL_ENTRY(getgroups);
 281         UWRAP_SYMBOL_ENTRY(setgroups);
 282 #ifdef HAVE_SYSCALL
 283         UWRAP_SYMBOL_ENTRY(syscall);
 284 #endif
 285 };
 286 #undef UWRAP_SYMBOL_ENTRY
 287
 288 /*****************
 289  * LIBPTHREAD
 290  *****************/
 291 /* Yeah... I'm pig. I overloading macro here... So what? */
 292 #define UWRAP_SYMBOL_ENTRY(i) \
 293         union { \
 294                 __libpthread_##i f; \
 295                 void *obj; \
 296         } _libpthread_##i
 297
 298 typedef int (*__libpthread_pthread_create)(pthread_t *thread,
 299                                     const pthread_attr_t *attr,
 300                                     void *(*start_routine) (void *),
 301                                     void *arg);
 302 typedef void (*__libpthread_pthread_exit)(void *retval);
 303
 304 struct uwrap_libpthread_symbols {
 305         UWRAP_SYMBOL_ENTRY(pthread_create);
 306         UWRAP_SYMBOL_ENTRY(pthread_exit);
 307 };
 308 #undef UWRAP_SYMBOL_ENTRY
 309
 310 /*
 311  * We keep the virtualised euid/egid/groups information here
 312  */
 313 struct uwrap_thread {
 314         bool enabled;
 315
 316         uid_t ruid;
 317         uid_t euid;
 318         uid_t suid;
 319
 320         gid_t rgid;
 321         gid_t egid;
 322         gid_t sgid;
 323
 324         int ngroups;
 325         gid_t *groups;
 326
 327         struct uwrap_thread *next;
 328         struct uwrap_thread *prev;
 329 };
 330
 331 struct uwrap {
 332         struct {
 333                 void *handle;
 334                 struct uwrap_libc_symbols symbols;
 335         } libc;
 336
 337         struct {
 338                 void *handle;
 339                 struct uwrap_libpthread_symbols symbols;
 340         } libpthread;
 341
 342         bool initialised;
 343
 344         /* Real uid and gid of user who run uid wrapper */
 345         uid_t myuid;
 346         gid_t mygid;
 347
 348         struct uwrap_thread *ids;
 349 };
 350
 351 static struct uwrap uwrap;
 352
 353 /* Shortcut to the list item */
 354 static UWRAP_THREAD struct uwrap_thread *uwrap_tls_id;
 355
 356 /* The mutex or accessing the id */
 357 static pthread_mutex_t uwrap_id_mutex = PTHREAD_MUTEX_INITIALIZER;
 358
 359 /* The mutex for accessing the global libc.symbols */
 360 static pthread_mutex_t libc_symbol_binding_mutex = PTHREAD_MUTEX_INITIALIZER;
 361
 362 /* The mutex for accessing the global libpthread.symbols */
 363 static pthread_mutex_t libpthread_symbol_binding_mutex = PTHREAD_MUTEX_INITIALIZER;
 364
 365 /*********************************************************
 366  * UWRAP PROTOTYPES
 367  *********************************************************/
 368
 369 bool uid_wrapper_enabled(void);
 370 void uwrap_constructor(void) CONSTRUCTOR_ATTRIBUTE;
 371 void uwrap_destructor(void) DESTRUCTOR_ATTRIBUTE;
 372
 373 /*********************************************************
 374  * UWRAP LIBC LOADER FUNCTIONS
 375  *********************************************************/
 376
 377 enum uwrap_lib {
 378     UWRAP_LIBC,
 379     UWRAP_LIBNSL,
 380     UWRAP_LIBSOCKET,
 381     UWRAP_LIBPTHREAD,
 382 };
 383
 384 static void *uwrap_load_lib_handle(enum uwrap_lib lib)
 385 {
 386         int flags = RTLD_LAZY;
 387         void *handle = NULL;
 388         int i;
 389
 390 #ifdef RTLD_DEEPBIND
 391         flags |= RTLD_DEEPBIND;
 392 #endif
 393
 394         switch (lib) {
 395         case UWRAP_LIBNSL:
 396                 /* FALL TROUGH */
 397         case UWRAP_LIBSOCKET:
 398                 /* FALL TROUGH */
 399         case UWRAP_LIBC:
 400                 handle = uwrap.libc.handle;
 401                 if (handle == NULL) {
 402                         for (i = 10; i >= 0; i--) {
 403                                 char soname[256] = {0};
 404
 405                                 snprintf(soname, sizeof(soname), "libc.so.%d", i);
 406                                 handle = dlopen(soname, flags);
 407                                 if (handle != NULL) {
 408                                         break;
 409                                 }
 410                         }
 411
 412                         uwrap.libc.handle = handle;
 413                 }
 414                 break;
 415         case UWRAP_LIBPTHREAD:
 416                 handle = uwrap.libpthread.handle;
 417                 if (handle == NULL) {
 418                         handle = dlopen("libpthread.so.0", flags);
 419                         if (handle != NULL) {
 420                                 break;
 421                         }
 422                 }
 423                 break;
 424         }
 425
 426         if (handle == NULL) {
 427 #ifdef RTLD_NEXT
 428                 handle = uwrap.libc.handle = RTLD_NEXT;
 429 #else
 430                 fprintf(stderr,
 431                         "Failed to dlopen library: %s\n",
 432                         dlerror());
 433                 exit(-1);
 434 #endif
 435         }
 436
 437         return handle;
 438 }
 439
 440 static void *_uwrap_bind_symbol(enum uwrap_lib lib, const char *fn_name)
 441 {
 442         void *handle;
 443         void *func;
 444
 445         handle = uwrap_load_lib_handle(lib);
 446
 447         func = dlsym(handle, fn_name);
 448         if (func == NULL) {
 449                 fprintf(stderr,
 450                         "Failed to find %s: %s\n",
 451                         fn_name, dlerror());
 452                 exit(-1);
 453         }
 454
 455         return func;
 456 }
 457
 458 #define uwrap_bind_symbol_libc(sym_name) \
 459         UWRAP_LOCK(libc_symbol_binding); \
 460         if (uwrap.libc.symbols._libc_##sym_name.obj == NULL) { \
 461                 uwrap.libc.symbols._libc_##sym_name.obj = \
 462                         _uwrap_bind_symbol(UWRAP_LIBC, #sym_name); \
 463         } \
 464         UWRAP_UNLOCK(libc_symbol_binding)
 465
 466 #define uwrap_bind_symbol_libpthread(sym_name) \
 467         UWRAP_LOCK(libpthread_symbol_binding); \
 468         if (uwrap.libpthread.symbols._libpthread_##sym_name.obj == NULL) { \
 469                 uwrap.libpthread.symbols._libpthread_##sym_name.obj = \
 470                         _uwrap_bind_symbol(UWRAP_LIBPTHREAD, #sym_name); \
 471         } \
 472         UWRAP_UNLOCK(libpthread_symbol_binding)
 473
 474 /*
 475  * IMPORTANT
 476  *
 477  * Functions expeciall from libc need to be loaded individually, you can't load
 478  * all at once or gdb will segfault at startup. The same applies to valgrind and
 479  * has probably something todo with with the linker.
 480  * So we need load each function at the point it is called the first time.
 481  */
 482 static int libc_setuid(uid_t uid)
 483 {
 484         uwrap_bind_symbol_libc(setuid);
 485
 486         return uwrap.libc.symbols._libc_setuid.f(uid);
 487 }
 488
 489 static uid_t libc_getuid(void)
 490 {
 491         uwrap_bind_symbol_libc(getuid);
 492
 493         return uwrap.libc.symbols._libc_getuid.f();
 494 }
 495
 496 #ifdef HAVE_SETEUID
 497 static int libc_seteuid(uid_t euid)
 498 {
 499         uwrap_bind_symbol_libc(seteuid);
 500
 501         return uwrap.libc.symbols._libc_seteuid.f(euid);
 502 }
 503 #endif
 504
 505 #ifdef HAVE_SETREUID
 506 static int libc_setreuid(uid_t ruid, uid_t euid)
 507 {
 508         uwrap_bind_symbol_libc(setreuid);
 509
 510         return uwrap.libc.symbols._libc_setreuid.f(ruid, euid);
 511 }
 512 #endif
 513
 514 #ifdef HAVE_SETRESUID
 515 static int libc_setresuid(uid_t ruid, uid_t euid, uid_t suid)
 516 {
 517         uwrap_bind_symbol_libc(setresuid);
 518
 519         return uwrap.libc.symbols._libc_setresuid.f(ruid, euid, suid);
 520 }
 521 #endif
 522
 523 #ifdef HAVE_GETRESUID
 524 static int libc_getresuid(uid_t *ruid, uid_t *euid, uid_t *suid)
 525 {
 526         uwrap_bind_symbol_libc(getresuid);
 527
 528         return uwrap.libc.symbols._libc_getresuid.f(ruid, euid, suid);
 529 }
 530 #endif
 531
 532 static uid_t libc_geteuid(void)
 533 {
 534         uwrap_bind_symbol_libc(geteuid);
 535
 536         return uwrap.libc.symbols._libc_geteuid.f();
 537 }
 538
 539 static int libc_setgid(gid_t gid)
 540 {
 541         uwrap_bind_symbol_libc(setgid);
 542
 543         return uwrap.libc.symbols._libc_setgid.f(gid);
 544 }
 545
 546 static gid_t libc_getgid(void)
 547 {
 548         uwrap_bind_symbol_libc(getgid);
 549
 550         return uwrap.libc.symbols._libc_getgid.f();
 551 }
 552
 553 #ifdef HAVE_SETEGID
 554 static int libc_setegid(gid_t egid)
 555 {
 556         uwrap_bind_symbol_libc(setegid);
 557
 558         return uwrap.libc.symbols._libc_setegid.f(egid);
 559 }
 560 #endif
 561
 562 #ifdef HAVE_SETREGID
 563 static int libc_setregid(gid_t rgid, gid_t egid)
 564 {
 565         uwrap_bind_symbol_libc(setregid);
 566
 567         return uwrap.libc.symbols._libc_setregid.f(rgid, egid);
 568 }
 569 #endif
 570
 571 #ifdef HAVE_SETRESGID
 572 static int libc_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
 573 {
 574         uwrap_bind_symbol_libc(setresgid);
 575
 576         return uwrap.libc.symbols._libc_setresgid.f(rgid, egid, sgid);
 577 }
 578 #endif
 579
 580 #ifdef HAVE_GETRESGID
 581 static int libc_getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid)
 582 {
 583         uwrap_bind_symbol_libc(setresgid);
 584
 585         return uwrap.libc.symbols._libc_getresgid.f(rgid, egid, sgid);
 586 }
 587 #endif
 588
 589 static gid_t libc_getegid(void)
 590 {
 591         uwrap_bind_symbol_libc(getegid);
 592
 593         return uwrap.libc.symbols._libc_getegid.f();
 594 }
 595
 596 static int libc_getgroups(int size, gid_t list[])
 597 {
 598         uwrap_bind_symbol_libc(getgroups);
 599
 600         return uwrap.libc.symbols._libc_getgroups.f(size, list);
 601 }
 602
 603 static int libc_setgroups(size_t size, const gid_t *list)
 604 {
 605         uwrap_bind_symbol_libc(setgroups);
 606
 607         return uwrap.libc.symbols._libc_setgroups.f(size, list);
 608 }
 609
 610 #ifdef HAVE_SYSCALL
 611 DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE
 612 static long int libc_vsyscall(long int sysno, va_list va)
 613 {
 614         long int args[8];
 615         long int rc;
 616         int i;
 617
 618         uwrap_bind_symbol_libc(syscall);
 619
 620         for (i = 0; i < 8; i++) {
 621                 args[i] = va_arg(va, long int);
 622         }
 623
 624         rc = uwrap.libc.symbols._libc_syscall.f(sysno,
 625                                           args[0],
 626                                           args[1],
 627                                           args[2],
 628                                           args[3],
 629                                           args[4],
 630                                           args[5],
 631                                           args[6],
 632                                           args[7]);
 633
 634         return rc;
 635 }
 636 #endif
 637
 638 /*
 639  * This part is "optimistic".
 640  * Thread can ends without pthread_exit call.
 641  */
 642 static void libpthread_pthread_exit(void *retval)
 643 {
 644         uwrap_bind_symbol_libpthread(pthread_exit);
 645
 646         uwrap.libpthread.symbols._libpthread_pthread_exit.f(retval);
 647 }
 648
 649 static void uwrap_pthread_exit(void *retval)
 650 {
 651         struct uwrap_thread *id = uwrap_tls_id;
 652
 653         UWRAP_LOG(UWRAP_LOG_DEBUG, "Cleanup thread");
 654
 655         UWRAP_LOCK(uwrap_id);
 656         if (id == NULL) {
 657                 UWRAP_UNLOCK(uwrap_id);
 658                 libpthread_pthread_exit(retval);
 659                 return;
 660         }
 661
 662         UWRAP_DLIST_REMOVE(uwrap.ids, id);
 663         SAFE_FREE(id->groups);
 664         SAFE_FREE(id);
 665         uwrap_tls_id = NULL;
 666
 667         UWRAP_UNLOCK(uwrap_id);
 668
 669         libpthread_pthread_exit(retval);
 670 }
 671
 672 void pthread_exit(void *retval)
 673 {
 674         if (!uid_wrapper_enabled()) {
 675                 libpthread_pthread_exit(retval);
 676         };
 677
 678         uwrap_pthread_exit(retval);
 679
 680         /* Calm down gcc warning. */
 681         exit(666);
 682 }
 683
 684 static int libpthread_pthread_create(pthread_t *thread,
 685                                 const pthread_attr_t *attr,
 686                                 void *(*start_routine) (void *),
 687                                 void *arg)
 688 {
 689         uwrap_bind_symbol_libpthread(pthread_create);
 690         return uwrap.libpthread.symbols._libpthread_pthread_create.f(thread,
 691                                                                      attr,
 692                                                                      start_routine,
 693                                                                      arg);
 694 }
 695
 696 struct uwrap_pthread_create_args {
 697         struct uwrap_thread *id;
 698         void *(*start_routine) (void *);
 699         void *arg;
 700 };
 701
 702 static void *uwrap_pthread_create_start(void *_a)
 703 {
 704         struct uwrap_pthread_create_args *a =
 705                 (struct uwrap_pthread_create_args *)_a;
 706         void *(*start_routine) (void *) = a->start_routine;
 707         void *arg = a->arg;
 708         struct uwrap_thread *id = a->id;
 709
 710         SAFE_FREE(a);
 711
 712         uwrap_tls_id = id;
 713
 714         return start_routine(arg);
 715 }
 716
 717 static int uwrap_pthread_create(pthread_t *thread,
 718                                  const pthread_attr_t *attr,
 719                                  void *(*start_routine) (void *),
 720                                  void *arg)
 721 {
 722         struct uwrap_pthread_create_args *args;
 723         struct uwrap_thread *src_id = uwrap_tls_id;
 724         int ret;
 725
 726         args = malloc(sizeof(struct uwrap_pthread_create_args));
 727         if (args == NULL) {
 728                 UWRAP_LOG(UWRAP_LOG_ERROR,
 729                           "uwrap_pthread_create: Unable to allocate memory");
 730                 errno = ENOMEM;
 731                 return -1;
 732         }
 733         args->start_routine = start_routine;
 734         args->arg = arg;
 735
 736         args->id = calloc(1, sizeof(struct uwrap_thread));
 737         if (args->id == NULL) {
 738                 SAFE_FREE(args);
 739                 UWRAP_LOG(UWRAP_LOG_ERROR,
 740                           "uwrap_pthread_create: Unable to allocate memory");
 741                 errno = ENOMEM;
 742                 return -1;
 743         }
 744
 745         UWRAP_LOCK(uwrap_id);
 746
 747         args->id->groups = malloc(sizeof(gid_t) * src_id->ngroups);
 748         if (args->id->groups == NULL) {
 749                 UWRAP_UNLOCK(uwrap_id);
 750                 SAFE_FREE(args->id);
 751                 SAFE_FREE(args);
 752                 UWRAP_LOG(UWRAP_LOG_ERROR,
 753                           "uwrap_pthread_create: Unable to allocate memory again");
 754                 errno = ENOMEM;
 755                 return -1;
 756         }
 757
 758         args->id->ruid = src_id->ruid;
 759         args->id->euid = src_id->euid;
 760         args->id->suid = src_id->suid;
 761
 762         args->id->rgid = src_id->rgid;
 763         args->id->egid = src_id->egid;
 764         args->id->sgid = src_id->sgid;
 765
 766         args->id->enabled = src_id->enabled;
 767
 768         args->id->ngroups = src_id->ngroups;
 769         if (src_id->groups != NULL) {
 770                 memcpy(args->id->groups, src_id->groups,
 771                        sizeof(gid_t) * src_id->ngroups);
 772         } else {
 773                 SAFE_FREE(args->id->groups);
 774         }
 775
 776         UWRAP_DLIST_ADD(uwrap.ids, args->id);
 777         UWRAP_UNLOCK(uwrap_id);
 778
 779         ret = libpthread_pthread_create(thread, attr,
 780                                         uwrap_pthread_create_start,
 781                                         args);
 782         if (ret != 0) {
 783                 return ret;
 784         }
 785
 786         return ret;
 787 }
 788
 789 int pthread_create(pthread_t *thread,
 790                     const pthread_attr_t *attr,
 791                     void *(*start_routine) (void *),
 792                     void *arg)
 793 {
 794         if (!uid_wrapper_enabled()) {
 795                 return libpthread_pthread_create(thread,
 796                                            attr,
 797                                            start_routine,
 798                                            arg);
 799         };
 800
 801         return uwrap_pthread_create(thread,
 802                                     attr,
 803                                     start_routine,
 804                                     arg);
 805 }
 806
 807 /*********************************************************
 808  * UWRAP ID HANDLING
 809  *********************************************************/
 810
 811 static void uwrap_thread_prepare(void)
 812 {
 813         struct uwrap_thread *id = uwrap_tls_id;
 814
 815         /* uid_wrapper is loaded but not enabled */
 816         if (id == NULL) {
 817                 return;
 818         }
 819
 820         UWRAP_LOCK_ALL;
 821
 822         /*
 823          * What happens if another atfork prepare functions calls a uwrap
 824          * function? So disable it in case another atfork prepare function
 825          * calls a (s)uid function. We disable uid_wrapper only for thread
 826          * (process) which called fork.
 827          */
 828         id->enabled = false;
 829 }
 830
 831 static void uwrap_thread_parent(void)
 832 {
 833         struct uwrap_thread *id = uwrap_tls_id;
 834
 835         /* uid_wrapper is loaded but not enabled */
 836         if (id == NULL) {
 837                 return;
 838         }
 839
 840         id->enabled = true;
 841
 842         UWRAP_UNLOCK_ALL;
 843 }
 844
 845 static void uwrap_thread_child(void)
 846 {
 847         struct uwrap_thread *id = uwrap_tls_id;
 848         struct uwrap_thread *u = uwrap.ids;
 849
 850         /* uid_wrapper is loaded but not enabled */
 851         if (id == NULL) {
 852                 return;
 853         }
 854
 855         /*
 856          * "Garbage collector" - Inspired by DESTRUCTOR.
 857          * All threads (except one which called fork()) are dead now.. Dave
 858          * That's what posix said...
 859          */
 860         while (u != NULL) {
 861                 if (u == id) {
 862                         /* Skip this item. */
 863                         u = uwrap.ids->next;
 864                         continue;
 865                 }
 866
 867                 UWRAP_DLIST_REMOVE(uwrap.ids, u);
 868
 869                 SAFE_FREE(u->groups);
 870                 SAFE_FREE(u);
 871
 872                 u = uwrap.ids;
 873         }
 874
 875         id->enabled = true;
 876
 877         UWRAP_UNLOCK_ALL;
 878 }
 879
 880 static void uwrap_init(void)
 881 {
 882         const char *env;
 883
 884         UWRAP_LOCK(uwrap_id);
 885
 886         if (uwrap.initialised) {
 887                 struct uwrap_thread *id = uwrap_tls_id;
 888
 889                 if (uwrap.ids == NULL) {
 890                         UWRAP_UNLOCK(uwrap_id);
 891                         return;
 892                 }
 893
 894                 if (id == NULL) {
 895                         UWRAP_LOG(UWRAP_LOG_ERROR,
 896                                   "Invalid id for thread");
 897                         exit(-1);
 898                 }
 899
 900                 UWRAP_UNLOCK(uwrap_id);
 901                 return;
 902         }
 903
 904         UWRAP_LOG(UWRAP_LOG_DEBUG, "Initialize uid_wrapper");
 905
 906         uwrap.initialised = true;
 907
 908         env = getenv("UID_WRAPPER");
 909         if (env != NULL && env[0] == '1') {
 910                 const char *root = getenv("UID_WRAPPER_ROOT");
 911                 struct uwrap_thread *id;
 912
 913                 id = calloc(1, sizeof(struct uwrap_thread));
 914                 if (id == NULL) {
 915                         UWRAP_LOG(UWRAP_LOG_ERROR,
 916                                   "Unable to allocate memory for main id");
 917                         exit(-1);
 918                 }
 919
 920                 UWRAP_DLIST_ADD(uwrap.ids, id);
 921                 uwrap_tls_id = id;
 922
 923                 uwrap.myuid = libc_geteuid();
 924                 uwrap.mygid = libc_getegid();
 925
 926                 /* put us in one group */
 927                 if (root != NULL && root[0] == '1') {
 928                         id->ruid = id->euid = id->suid = 0;
 929                         id->rgid = id->egid = id->sgid = 0;
 930
 931                         id->groups = malloc(sizeof(gid_t) * 1);
 932                         if (id->groups == NULL) {
 933                                 UWRAP_LOG(UWRAP_LOG_ERROR,
 934                                           "Unable to allocate memory");
 935                                 exit(-1);
 936                         }
 937
 938                         id->ngroups = 1;
 939                         id->groups[0] = 0;
 940
 941                 } else {
 942                         id->ruid = id->euid = id->suid = uwrap.myuid;
 943                         id->rgid = id->egid = id->sgid = uwrap.mygid;
 944
 945                         id->ngroups = libc_getgroups(0, NULL);
 946                         if (id->ngroups == -1) {
 947                                 UWRAP_LOG(UWRAP_LOG_ERROR,
 948                                           "Unable to call libc_getgroups in uwrap_init.");
 949                                 exit(-1);
 950                         }
 951                         id->groups = malloc(sizeof(gid_t) * id->ngroups);
 952                         if (id->groups == NULL) {
 953                                 UWRAP_LOG(UWRAP_LOG_ERROR, "Unable to allocate memory");
 954                                 exit(-1);
 955                         }
 956                         if (libc_getgroups(id->ngroups, id->groups) == -1) {
 957                                 UWRAP_LOG(UWRAP_LOG_ERROR,
 958                                           "Unable to call libc_getgroups again in uwrap_init.");
 959                                 id->groups = 0;
 960                                 /*
 961                                  * Deallocation of uwrap.groups is handled by
 962                                  * library destructor.
 963                                  */
 964                                 exit(-1);
 965                         }
 966                 }
 967
 968                 id->enabled = true;
 969
 970                 UWRAP_LOG(UWRAP_LOG_DEBUG,
 971                           "Enabled uid_wrapper as %s (real uid=%u)",
 972                           id->ruid == 0 ? "root" : "user",
 973                           (unsigned int)uwrap.myuid);
 974         }
 975
 976         UWRAP_UNLOCK(uwrap_id);
 977
 978         UWRAP_LOG(UWRAP_LOG_DEBUG, "Succeccfully initialized uid_wrapper");
 979 }
 980
 981 bool uid_wrapper_enabled(void)
 982 {
 983         struct uwrap_thread *id = uwrap_tls_id;
 984         bool enabled;
 985
 986         if (id == NULL) {
 987                 return false;
 988         }
 989
 990         UWRAP_LOCK(uwrap_id);
 991         enabled = id->enabled;
 992         UWRAP_UNLOCK(uwrap_id);
 993
 994         return enabled;
 995 }
 996
 997 /*
 998  * UWRAP_SETxUID FUNCTIONS
 999  */
1000
1001 static int uwrap_setresuid_args(uid_t ruid, uid_t euid, uid_t suid)
1002 {
1003         struct uwrap_thread *id = uwrap_tls_id;
1004
1005         UWRAP_LOG(UWRAP_LOG_TRACE,
1006                   "ruid %d -> %d, euid %d -> %d, suid %d -> %d",
1007                   id->ruid, ruid, id->euid, euid, id->suid, suid);
1008
1009         if (id->euid != 0) {
1010                 if (ruid != (uid_t)-1 &&
1011                     ruid != id->ruid &&
1012                     ruid != id->euid &&
1013                     ruid != id->suid) {
1014                         errno = EPERM;
1015                         return -1;
1016                 }
1017                 if (euid != (uid_t)-1 &&
1018                     euid != id->ruid &&
1019                     euid != id->euid &&
1020                     euid != id->suid) {
1021                         errno = EPERM;
1022                         return -1;
1023                 }
1024                 if (suid != (uid_t)-1 &&
1025                     suid != id->ruid &&
1026                     suid != id->euid &&
1027                     suid != id->suid) {
1028                         errno = EPERM;
1029                         return -1;
1030                 }
1031         }
1032
1033         return 0;
1034 }
1035
1036 static int uwrap_setresuid_thread(uid_t ruid, uid_t euid, uid_t suid)
1037 {
1038         struct uwrap_thread *id = uwrap_tls_id;
1039         int rc;
1040
1041         UWRAP_LOG(UWRAP_LOG_TRACE,
1042                   "ruid %d -> %d, euid %d -> %d, suid %d -> %d",
1043                   id->ruid, ruid, id->euid, euid, id->suid, suid);
1044
1045         rc = uwrap_setresuid_args(ruid, euid, suid);
1046         if (rc != 0) {
1047                 return rc;
1048         }
1049
1050         UWRAP_LOCK(uwrap_id);
1051
1052         if (ruid != (uid_t)-1) {
1053                 id->ruid = ruid;
1054         }
1055
1056         if (euid != (uid_t)-1) {
1057                 id->euid = euid;
1058         }
1059
1060         if (suid != (uid_t)-1) {
1061                 id->suid = suid;
1062         }
1063
1064         UWRAP_UNLOCK(uwrap_id);
1065
1066         return 0;
1067 }
1068
1069 static int uwrap_setresuid(uid_t ruid, uid_t euid, uid_t suid)
1070 {
1071         struct uwrap_thread *id = uwrap_tls_id;
1072         int rc;
1073
1074         UWRAP_LOG(UWRAP_LOG_TRACE,
1075                   "ruid %d -> %d, euid %d -> %d, suid %d -> %d",
1076                   id->ruid, ruid, id->euid, euid, id->suid, suid);
1077
1078         rc = uwrap_setresuid_args(ruid, euid, suid);
1079         if (rc != 0) {
1080                 return rc;
1081         }
1082
1083         UWRAP_LOCK(uwrap_id);
1084
1085         for (id = uwrap.ids; id; id = id->next) {
1086                 if (ruid != (uid_t)-1) {
1087                         id->ruid = ruid;
1088                 }
1089
1090                 if (euid != (uid_t)-1) {
1091                         id->euid = euid;
1092                 }
1093
1094                 if (suid != (uid_t)-1) {
1095                         id->suid = suid;
1096                 }
1097         }
1098
1099         UWRAP_UNLOCK(uwrap_id);
1100
1101         return 0;
1102 }
1103
1104
1105 /*
1106  * UWRAP_GETxUID FUNCTIONS
1107  */
1108
1109 #ifdef HAVE_GETRESUID
1110 static int uwrap_getresuid(uid_t *ruid, uid_t *euid, uid_t *suid)
1111 {
1112         struct uwrap_thread *id = uwrap_tls_id;
1113
1114         UWRAP_LOCK(uwrap_id);
1115
1116         *ruid = id->ruid;
1117         *euid = id->euid;
1118         *suid = id->suid;
1119
1120         UWRAP_UNLOCK(uwrap_id);
1121
1122         return 0;
1123 }
1124 #endif
1125
1126 #ifdef HAVE_GETRESGID
1127 static int uwrap_getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid)
1128 {
1129         struct uwrap_thread *id = uwrap_tls_id;
1130
1131         UWRAP_LOCK(uwrap_id);
1132
1133         *rgid = id->rgid;
1134         *egid = id->egid;
1135         *sgid = id->sgid;
1136
1137         UWRAP_UNLOCK(uwrap_id);
1138
1139         return 0;
1140 }
1141 #endif
1142
1143 /*
1144  * SETUID
1145  */
1146 int setuid(uid_t uid)
1147 {
1148         if (!uid_wrapper_enabled()) {
1149                 return libc_setuid(uid);
1150         }
1151
1152         uwrap_init();
1153         return uwrap_setresuid(uid, -1, -1);
1154 }
1155
1156 #ifdef HAVE_SETEUID
1157 int seteuid(uid_t euid)
1158 {
1159         if (euid == (uid_t)-1) {
1160                 errno = EINVAL;
1161                 return -1;
1162         }
1163
1164         if (!uid_wrapper_enabled()) {
1165                 return libc_seteuid(euid);
1166         }
1167
1168         uwrap_init();
1169         return uwrap_setresuid(-1, euid, -1);
1170 }
1171 #endif
1172
1173 #ifdef HAVE_SETREUID
1174 int setreuid(uid_t ruid, uid_t euid)
1175 {
1176         if (ruid == (uid_t)-1 && euid == (uid_t)-1) {
1177                 errno = EINVAL;
1178                 return -1;
1179         }
1180
1181         if (!uid_wrapper_enabled()) {
1182                 return libc_setreuid(ruid, euid);
1183         }
1184
1185         uwrap_init();
1186         return uwrap_setresuid(ruid, euid, -1);
1187 }
1188 #endif
1189
1190 #ifdef HAVE_SETRESUID
1191 int setresuid(uid_t ruid, uid_t euid, uid_t suid)
1192 {
1193         if (!uid_wrapper_enabled()) {
1194                 return libc_setresuid(ruid, euid, suid);
1195         }
1196
1197         uwrap_init();
1198         return uwrap_setresuid(ruid, euid, suid);
1199 }
1200 #endif
1201
1202 #ifdef HAVE_GETRESUID
1203 int getresuid(uid_t *ruid, uid_t *euid, uid_t *suid)
1204 {
1205         if (!uid_wrapper_enabled()) {
1206                 return libc_getresuid(ruid, euid, suid);
1207         }
1208
1209         uwrap_init();
1210         return uwrap_getresuid(ruid, euid, suid);
1211 }
1212 #endif
1213
1214 /*
1215  * GETUID
1216  */
1217 static uid_t uwrap_getuid(void)
1218 {
1219         struct uwrap_thread *id = uwrap_tls_id;
1220         uid_t uid;
1221
1222         UWRAP_LOCK(uwrap_id);
1223         uid = id->ruid;
1224         UWRAP_UNLOCK(uwrap_id);
1225
1226         return uid;
1227 }
1228
1229 uid_t getuid(void)
1230 {
1231         if (!uid_wrapper_enabled()) {
1232                 return libc_getuid();
1233         }
1234
1235         uwrap_init();
1236         return uwrap_getuid();
1237 }
1238
1239 /*
1240  * GETEUID
1241  */
1242 static uid_t uwrap_geteuid(void)
1243 {
1244         const char *env = getenv("UID_WRAPPER_MYUID");
1245         struct uwrap_thread *id = uwrap_tls_id;
1246         uid_t uid;
1247
1248         UWRAP_LOCK(uwrap_id);
1249         uid = id->euid;
1250         UWRAP_UNLOCK(uwrap_id);
1251
1252         /* Disable root and return myuid */
1253         if (env != NULL && env[0] == '1') {
1254                 uid = uwrap.myuid;
1255         }
1256
1257         return uid;
1258 }
1259
1260 uid_t geteuid(void)
1261 {
1262         if (!uid_wrapper_enabled()) {
1263                 return libc_geteuid();
1264         }
1265
1266         uwrap_init();
1267         return uwrap_geteuid();
1268 }
1269
1270 static int uwrap_setresgid_thread(gid_t rgid, gid_t egid, gid_t sgid)
1271 {
1272         struct uwrap_thread *id = uwrap_tls_id;
1273
1274         if (rgid == (gid_t)-1 && egid == (gid_t)-1 && sgid == (gid_t)-1) {
1275                 errno = EINVAL;
1276                 return -1;
1277         }
1278
1279         UWRAP_LOCK(uwrap_id);
1280         if (rgid != (gid_t)-1) {
1281                 id->rgid = rgid;
1282         }
1283
1284         if (egid != (gid_t)-1) {
1285                 id->egid = egid;
1286         }
1287
1288         if (sgid != (gid_t)-1) {
1289                 id->sgid = sgid;
1290         }
1291
1292         UWRAP_UNLOCK(uwrap_id);
1293
1294         return 0;
1295 }
1296
1297 static int uwrap_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
1298 {
1299         struct uwrap_thread *id;
1300
1301         if (rgid == (gid_t)-1 && egid == (gid_t)-1 && sgid == (gid_t)-1) {
1302                 errno = EINVAL;
1303                 return -1;
1304         }
1305
1306         UWRAP_LOCK(uwrap_id);
1307         for (id = uwrap.ids; id; id = id->next) {
1308                 if (rgid != (gid_t)-1) {
1309                         id->rgid = rgid;
1310                 }
1311
1312                 if (egid != (gid_t)-1) {
1313                         id->egid = egid;
1314                 }
1315
1316                 if (sgid != (gid_t)-1) {
1317                         id->sgid = sgid;
1318                 }
1319         }
1320         UWRAP_UNLOCK(uwrap_id);
1321
1322         return 0;
1323 }
1324
1325 /*
1326  * SETGID
1327  */
1328 int setgid(gid_t gid)
1329 {
1330         if (!uid_wrapper_enabled()) {
1331                 return libc_setgid(gid);
1332         }
1333
1334         uwrap_init();
1335         return uwrap_setresgid(gid, -1, -1);
1336 }
1337
1338 #ifdef HAVE_SETEGID
1339 int setegid(gid_t egid)
1340 {
1341         if (!uid_wrapper_enabled()) {
1342                 return libc_setegid(egid);
1343         }
1344
1345         uwrap_init();
1346         return uwrap_setresgid(-1, egid, -1);
1347 }
1348 #endif
1349
1350 #ifdef HAVE_SETREGID
1351 int setregid(gid_t rgid, gid_t egid)
1352 {
1353         if (!uid_wrapper_enabled()) {
1354                 return libc_setregid(rgid, egid);
1355         }
1356
1357         uwrap_init();
1358         return uwrap_setresgid(rgid, egid, -1);
1359 }
1360 #endif
1361
1362 #ifdef HAVE_SETRESGID
1363 int setresgid(gid_t rgid, gid_t egid, gid_t sgid)
1364 {
1365         if (!uid_wrapper_enabled()) {
1366                 return libc_setresgid(rgid, egid, sgid);
1367         }
1368
1369         uwrap_init();
1370         return uwrap_setresgid(rgid, egid, sgid);
1371 }
1372 #endif
1373
1374 #ifdef HAVE_GETRESGID
1375 int getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid)
1376 {
1377         if (!uid_wrapper_enabled()) {
1378                 return libc_getresgid(rgid, egid, sgid);
1379         }
1380
1381         uwrap_init();
1382         return uwrap_getresgid(rgid, egid, sgid);
1383 }
1384 #endif
1385
1386 /*
1387  * GETGID
1388  */
1389 static gid_t uwrap_getgid(void)
1390 {
1391         struct uwrap_thread *id = uwrap_tls_id;
1392         gid_t gid;
1393
1394         UWRAP_LOCK(uwrap_id);
1395         gid = id->rgid;
1396         UWRAP_UNLOCK(uwrap_id);
1397
1398         return gid;
1399 }
1400
1401 gid_t getgid(void)
1402 {
1403         if (!uid_wrapper_enabled()) {
1404                 return libc_getgid();
1405         }
1406
1407         uwrap_init();
1408         return uwrap_getgid();
1409 }
1410
1411 /*
1412  * GETEGID
1413  */
1414 static uid_t uwrap_getegid(void)
1415 {
1416         struct uwrap_thread *id = uwrap_tls_id;
1417         gid_t gid;
1418
1419         UWRAP_LOCK(uwrap_id);
1420         gid = id->egid;
1421         UWRAP_UNLOCK(uwrap_id);
1422
1423         return gid;
1424 }
1425
1426 uid_t getegid(void)
1427 {
1428         if (!uid_wrapper_enabled()) {
1429                 return libc_getegid();
1430         }
1431
1432         uwrap_init();
1433         return uwrap_getegid();
1434 }
1435
1436 static int uwrap_setgroups_thread(size_t size, const gid_t *list)
1437 {
1438         struct uwrap_thread *id = uwrap_tls_id;
1439         int rc = -1;
1440
1441         UWRAP_LOCK(uwrap_id);
1442
1443         if (size == 0) {
1444                 SAFE_FREE(id->groups);
1445                 id->ngroups = 0;
1446         } else if (size > 0) {
1447                 gid_t *tmp;
1448
1449                 tmp = realloc(id->groups, sizeof(gid_t) * size);
1450                 if (tmp == NULL) {
1451                         errno = ENOMEM;
1452                         goto out;
1453                 }
1454                 id->groups = tmp;
1455                 id->ngroups = size;
1456                 memcpy(id->groups, list, size * sizeof(gid_t));
1457         }
1458
1459         rc = 0;
1460 out:
1461         UWRAP_UNLOCK(uwrap_id);
1462
1463         return rc;
1464 }
1465
1466 static int uwrap_setgroups(size_t size, const gid_t *list)
1467 {
1468         struct uwrap_thread *id;
1469         int rc = -1;
1470
1471         UWRAP_LOCK(uwrap_id);
1472
1473         if (size == 0) {
1474                 for (id = uwrap.ids; id; id = id->next) {
1475                         SAFE_FREE(id->groups);
1476                         id->ngroups = 0;
1477
1478                 }
1479         } else if (size > 0) {
1480                 gid_t *tmp;
1481
1482                 for (id = uwrap.ids; id; id = id->next) {
1483                         tmp = realloc(id->groups, sizeof(gid_t) * size);
1484                         if (tmp == NULL) {
1485                                 errno = ENOMEM;
1486                                 goto out;
1487                         }
1488                         id->groups = tmp;
1489
1490                         id->ngroups = size;
1491                         memcpy(id->groups, list, size * sizeof(gid_t));
1492                 }
1493         }
1494
1495         rc = 0;
1496 out:
1497         UWRAP_UNLOCK(uwrap_id);
1498
1499         return rc;
1500 }
1501
1502 #ifdef HAVE_SETGROUPS_INT
1503 int setgroups(int size, const gid_t *list)
1504 #else
1505 int setgroups(size_t size, const gid_t *list)
1506 #endif
1507 {
1508         if (!uid_wrapper_enabled()) {
1509                 return libc_setgroups(size, list);
1510         }
1511
1512         uwrap_init();
1513         return uwrap_setgroups(size, list);
1514 }
1515
1516 static int uwrap_getgroups(int size, gid_t *list)
1517 {
1518         struct uwrap_thread *id = uwrap_tls_id;
1519         int ngroups;
1520
1521         UWRAP_LOCK(uwrap_id);
1522         ngroups = id->ngroups;
1523
1524         if (size > ngroups) {
1525                 size = ngroups;
1526         }
1527         if (size == 0) {
1528                 goto out;
1529         }
1530         if (size < ngroups) {
1531                 errno = EINVAL;
1532                 ngroups = -1;
1533         }
1534         memcpy(list, id->groups, size * sizeof(gid_t));
1535
1536 out:
1537         UWRAP_UNLOCK(uwrap_id);
1538
1539         return ngroups;
1540 }
1541
1542 int getgroups(int size, gid_t *list)
1543 {
1544         if (!uid_wrapper_enabled()) {
1545                 return libc_getgroups(size, list);
1546         }
1547
1548         uwrap_init();
1549         return uwrap_getgroups(size, list);
1550 }
1551
1552 #if (defined(HAVE_SYS_SYSCALL_H) || defined(HAVE_SYSCALL_H)) \
1553     && (defined(SYS_setreuid) || defined(SYS_setreuid32))
1554 static long int uwrap_syscall (long int sysno, va_list vp)
1555 {
1556         long int rc;
1557
1558         switch (sysno) {
1559                 /* gid */
1560                 case SYS_getgid:
1561 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1562                 case SYS_getgid32:
1563 #endif
1564                         {
1565                                 rc = uwrap_getgid();
1566                         }
1567                         break;
1568 #ifdef SYS_getegid
1569                 case SYS_getegid:
1570 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1571                 case SYS_getegid32:
1572 #endif
1573                         {
1574                                 rc = uwrap_getegid();
1575                         }
1576                         break;
1577 #endif /* SYS_getegid */
1578                 case SYS_setgid:
1579 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1580                 case SYS_setgid32:
1581 #endif
1582                         {
1583                                 gid_t gid = (gid_t) va_arg(vp, gid_t);
1584
1585                                 rc = uwrap_setresgid_thread(gid, -1, -1);
1586                         }
1587                         break;
1588                 case SYS_setregid:
1589 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1590                 case SYS_setregid32:
1591 #endif
1592                         {
1593                                 gid_t rgid = (gid_t) va_arg(vp, gid_t);
1594                                 gid_t egid = (gid_t) va_arg(vp, gid_t);
1595
1596                                 rc = uwrap_setresgid_thread(rgid, egid, -1);
1597                         }
1598                         break;
1599 #ifdef SYS_setresgid
1600                 case SYS_setresgid:
1601 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1602                 case SYS_setresgid32:
1603 #endif
1604                         {
1605                                 gid_t rgid = (gid_t) va_arg(vp, gid_t);
1606                                 gid_t egid = (gid_t) va_arg(vp, gid_t);
1607                                 gid_t sgid = (gid_t) va_arg(vp, gid_t);
1608
1609                                 rc = uwrap_setresgid_thread(rgid, egid, sgid);
1610                         }
1611                         break;
1612 #endif /* SYS_setresgid */
1613 #if defined(SYS_getresgid) && defined(HAVE_GETRESGID)
1614                 case SYS_getresgid:
1615 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1616                 case SYS_getresgid32:
1617 #endif
1618                         {
1619                                 gid_t *rgid = (gid_t *) va_arg(vp, gid_t *);
1620                                 gid_t *egid = (gid_t *) va_arg(vp, gid_t *);
1621                                 gid_t *sgid = (gid_t *) va_arg(vp, gid_t *);
1622
1623                                 rc = uwrap_getresgid(rgid, egid, sgid);
1624                         }
1625                         break;
1626 #endif /* SYS_getresgid && HAVE_GETRESGID */
1627
1628                 /* uid */
1629                 case SYS_getuid:
1630 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1631                 case SYS_getuid32:
1632 #endif
1633                         {
1634                                 rc = uwrap_getuid();
1635                         }
1636                         break;
1637 #ifdef SYS_geteuid
1638                 case SYS_geteuid:
1639 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1640                 case SYS_geteuid32:
1641 #endif
1642                         {
1643                                 rc = uwrap_geteuid();
1644                         }
1645                         break;
1646 #endif /* SYS_geteuid */
1647                 case SYS_setuid:
1648 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1649                 case SYS_setuid32:
1650 #endif
1651                         {
1652                                 uid_t uid = (uid_t) va_arg(vp, uid_t);
1653
1654                                 rc = uwrap_setresuid_thread(uid, -1, -1);
1655                         }
1656                         break;
1657                 case SYS_setreuid:
1658 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1659                 case SYS_setreuid32:
1660 #endif
1661                         {
1662                                 uid_t ruid = (uid_t) va_arg(vp, uid_t);
1663                                 uid_t euid = (uid_t) va_arg(vp, uid_t);
1664
1665                                 rc = uwrap_setresuid_thread(ruid, euid, -1);
1666                         }
1667                         break;
1668 #ifdef SYS_setresuid
1669                 case SYS_setresuid:
1670 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1671                 case SYS_setresuid32:
1672 #endif
1673                         {
1674                                 uid_t ruid = (uid_t) va_arg(vp, uid_t);
1675                                 uid_t euid = (uid_t) va_arg(vp, uid_t);
1676                                 uid_t suid = (uid_t) va_arg(vp, uid_t);
1677
1678                                 rc = uwrap_setresuid_thread(ruid, euid, suid);
1679                         }
1680                         break;
1681 #endif /* SYS_setresuid */
1682 #if defined(SYS_getresuid) && defined(HAVE_GETRESUID)
1683                 case SYS_getresuid:
1684 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1685                 case SYS_getresuid32:
1686 #endif
1687                         {
1688                                 uid_t *ruid = (uid_t *) va_arg(vp, uid_t *);
1689                                 uid_t *euid = (uid_t *) va_arg(vp, uid_t *);
1690                                 uid_t *suid = (uid_t *) va_arg(vp, uid_t *);
1691
1692                                 rc = uwrap_getresuid(ruid, euid, suid);
1693                         }
1694                         break;
1695 #endif /* SYS_getresuid && HAVE_GETRESUID*/
1696                 /* groups */
1697                 case SYS_setgroups:
1698 #ifdef HAVE_LINUX_32BIT_SYSCALLS
1699                 case SYS_setgroups32:
1700 #endif
1701                         {
1702                                 size_t size = (size_t) va_arg(vp, size_t);
1703                                 gid_t *list = (gid_t *) va_arg(vp, int *);
1704
1705                                 rc = uwrap_setgroups_thread(size, list);
1706                         }
1707                         break;
1708                 default:
1709                         UWRAP_LOG(UWRAP_LOG_DEBUG,
1710                                   "UID_WRAPPER calling non-wrapped syscall %lu",
1711                                   sysno);
1712
1713                         rc = libc_vsyscall(sysno, vp);
1714                         break;
1715         }
1716
1717         return rc;
1718 }
1719
1720 #ifdef HAVE_SYSCALL
1721 #ifdef HAVE_SYSCALL_INT
1722 int syscall (int sysno, ...)
1723 #else
1724 long int syscall (long int sysno, ...)
1725 #endif
1726 {
1727 #ifdef HAVE_SYSCALL_INT
1728         int rc;
1729 #else
1730         long int rc;
1731 #endif
1732         va_list va;
1733
1734         va_start(va, sysno);
1735
1736         if (!uid_wrapper_enabled()) {
1737                 rc = libc_vsyscall(sysno, va);
1738                 va_end(va);
1739                 return rc;
1740         }
1741
1742         uwrap_init();
1743         rc = uwrap_syscall(sysno, va);
1744         va_end(va);
1745
1746         return rc;
1747 }
1748 #endif /* HAVE_SYSCALL */
1749 #endif /* HAVE_SYS_SYSCALL_H || HAVE_SYSCALL_H */
1750
1751 /****************************
1752  * CONSTRUCTOR
1753  ***************************/
1754 void uwrap_constructor(void)
1755 {
1756         /*
1757         * If we hold a lock and the application forks, then the child
1758         * is not able to unlock the mutex and we are in a deadlock.
1759         * This should prevent such deadlocks.
1760         */
1761         pthread_atfork(&uwrap_thread_prepare,
1762                        &uwrap_thread_parent,
1763                        &uwrap_thread_child);
1764
1765         /* Here is safe place to call uwrap_init() and initialize data
1766          * for main process.
1767          */
1768         uwrap_init();
1769 }
1770
1771 /****************************
1772  * DESTRUCTOR
1773  ***************************/
1774
1775 /*
1776  * This function is called when the library is unloaded and makes sure that
1777  * resources are freed.
1778  */
1779 void uwrap_destructor(void)
1780 {
1781         struct uwrap_thread *u = uwrap.ids;
1782
1783         UWRAP_LOCK_ALL;
1784
1785         while (u != NULL) {
1786                 UWRAP_DLIST_REMOVE(uwrap.ids, u);
1787
1788                 SAFE_FREE(u->groups);
1789                 SAFE_FREE(u);
1790
1791                 u = uwrap.ids;
1792         }
1793
1794
1795         if (uwrap.libc.handle != NULL) {
1796                 dlclose(uwrap.libc.handle);
1797         }
1798
1799         if (uwrap.libpthread.handle != NULL) {
1800                 dlclose(uwrap.libpthread.handle);
1801         }
1802
1803         UWRAP_UNLOCK_ALL;
1804 }