fcgi_util.c

   1 /*
   2  * $Id: fcgi_util.c,v 1.15 2000/09/19 16:26:52 robs Exp $
   3  */
   4
   5 #include "fcgi.h"
   6
   7 /*******************************************************************************
   8  * Compute printable MD5 hash. Pool p is used for scratch as well as for
   9  * allocating the hash - use temp storage, and dup it if you need to keep it.
  10  */
  11 char *
  12 fcgi_util_socket_hash_filename(pool *p, const char *path,
  13         const char *user, const char *group)
  14 {
  15     char *buf = ap_pstrcat(p, path, user, group, NULL);
  16
  17     /* Canonicalize the path (remove "//", ".", "..") */
  18     ap_getparents(buf);
  19
  20     return ap_md5(p, (unsigned char *)buf);
  21 }
  22
  23 /*******************************************************************************
  24  * Return absolute path to file in either "regular" FCGI socket directory or
  25  * the dynamic directory.  Result is allocated in pool p.
  26  */
  27 const char *
  28 fcgi_util_socket_make_path_absolute(pool * const p,
  29         const char *const file, const int dynamic)
  30 {
  31     return (const char *)ap_pstrcat(p,
  32 #ifdef WIN32
  33         (dynamic ? fcgi_dynamic_dir : fcgi_socket_dir), file, NULL);
  34 #else
  35         (dynamic ? fcgi_dynamic_dir : fcgi_socket_dir), "/", file, NULL);
  36 #endif
  37 }
  38
  39 /*******************************************************************************
  40  * Allocate a new string from pool p with the name of a Unix/Domain socket's
  41  * lock file (used by dynamic only).
  42  */
  43 const char *
  44 fcgi_util_socket_get_lock_filename(pool *p, const char *socket_path)
  45 {
  46     return ap_pstrcat(p, socket_path, ".lock", NULL);
  47 }
  48
  49 #ifndef WIN32
  50 /*******************************************************************************
  51  * Build a Domain Socket Address structure, and calculate its size.
  52  * The error message is allocated from the pool p.  If you don't want the
  53  * struct sockaddr_un also allocated from p, pass it preallocated (!=NULL).
  54  */
  55 const char *
  56 fcgi_util_socket_make_domain_addr(pool *p, struct sockaddr_un **socket_addr,
  57         int *socket_addr_len, const char *socket_path)
  58 {
  59     int socket_pathLen = strlen(socket_path);
  60
  61     if (socket_pathLen >= sizeof((*socket_addr)->sun_path)) {
  62         return ap_pstrcat(p, "path \"", socket_path,
  63                        "\" is too long for a Domain socket", NULL);
  64     }
  65
  66     if (*socket_addr == NULL)
  67         *socket_addr = ap_pcalloc(p, sizeof(struct sockaddr_un));
  68     else
  69         memset(*socket_addr, 0, sizeof(struct sockaddr_un));
  70
  71     (*socket_addr)->sun_family = AF_UNIX;
  72     strcpy((*socket_addr)->sun_path, socket_path);
  73
  74     *socket_addr_len = SUN_LEN(*socket_addr);
  75     return NULL;
  76 }
  77 #endif
  78
  79 /*******************************************************************************
  80  * Convert a hostname or IP address string to an in_addr struct.
  81  */
  82 static int
  83 convert_string_to_in_addr(const char * const hostname, struct in_addr * const addr)
  84 {
  85     struct hostent *hp;
  86     int count;
  87
  88     addr->s_addr = inet_addr((char *)hostname);
  89
  90     if (addr->s_addr == INADDR_NONE) {
  91         if ((hp = gethostbyname((char *)hostname)) == NULL)
  92             return -1;
  93
  94         memcpy((char *) addr, hp->h_addr, hp->h_length);
  95         count = 0;
  96         while (hp->h_addr_list[count] != 0)
  97             count++;
  98
  99         return count;
 100     }
 101     return 1;
 102 }
 103
 104
 105 /*******************************************************************************
 106  * Build an Inet Socket Address structure, and calculate its size.
 107  * The error message is allocated from the pool p. If you don't want the
 108  * struct sockaddr_in also allocated from p, pass it preallocated (!=NULL).
 109  */
 110 const char *
 111 fcgi_util_socket_make_inet_addr(pool *p, struct sockaddr_in **socket_addr,
 112         int *socket_addr_len, const char *host, unsigned short port)
 113 {
 114     if (*socket_addr == NULL)
 115         *socket_addr = ap_pcalloc(p, sizeof(struct sockaddr_in));
 116     else
 117         memset(*socket_addr, 0, sizeof(struct sockaddr_in));
 118
 119     (*socket_addr)->sin_family = AF_INET;
 120     (*socket_addr)->sin_port = htons(port);
 121
 122     /* Get an in_addr represention of the host */
 123     if (host != NULL) {
 124         if (convert_string_to_in_addr(host, &(*socket_addr)->sin_addr) != 1) {
 125             return ap_pstrcat(p, "failed to resolve \"", host,
 126                            "\" to exactly one IP address", NULL);
 127         }
 128     } else {
 129       (*socket_addr)->sin_addr.s_addr = htonl(INADDR_ANY);
 130     }
 131
 132     *socket_addr_len = sizeof(struct sockaddr_in);
 133     return NULL;
 134 }
 135
 136 /*******************************************************************************
 137  * Determine if a process with uid/gid can access a file with mode permissions.
 138  */
 139 const char *
 140 fcgi_util_check_access(pool *tp,
 141         const char * const path, const struct stat *statBuf,
 142         const int mode, const uid_t uid, const gid_t gid)
 143 {
 144     if (statBuf == NULL) {
 145         static struct stat staticStatBuf;
 146
 147         if (stat(path, &staticStatBuf) < 0)
 148             return ap_psprintf(tp, "stat() failed: %s", strerror(errno));
 149         statBuf = &staticStatBuf;
 150     }
 151
 152 #ifndef WIN32
 153     /* If the uid owns the file, check the owner bits */
 154     if (uid == statBuf->st_uid) {
 155         if (mode & R_OK && !(statBuf->st_mode & S_IRUSR))
 156             return "read not allowed by owner";
 157         if (mode & W_OK && !(statBuf->st_mode & S_IWUSR))
 158             return "write not allowed by owner";
 159         if (mode & X_OK && !(statBuf->st_mode & S_IXUSR))
 160             return "execute not allowed by owner";
 161         return NULL;
 162     }
 163 #else
 164     if (mode & _S_IREAD && !(statBuf->st_mode & _S_IREAD))
 165         return "read not allowed";
 166     if (mode & _S_IWRITE && !(statBuf->st_mode & _S_IWRITE))
 167         return "write not allowed";
 168
 169     // I don't think this works on FAT, but since I don't know how to check..
 170     // if (mode & _S_IEXEC && !(statBuf->st_mode & _S_IEXEC))
 171     //     return "execute not allowed";
 172 #endif
 173
 174 #if  !defined(__EMX__) && !defined(WIN32)
 175     /* If the gid is same as the file's group, check the group bits */
 176     if (gid == statBuf->st_gid) {
 177         if (mode & R_OK && !(statBuf->st_mode & S_IRGRP))
 178             return "read not allowed by group";
 179         if (mode & W_OK && !(statBuf->st_mode & S_IWGRP))
 180             return "write not allowed by group";
 181         if (mode & X_OK && !(statBuf->st_mode & S_IXGRP))
 182             return "execute not allowed by group";
 183         return NULL;
 184     }
 185
 186     /* Get the user membership for the file's group.  If the
 187      * uid is a member, check the group bits. */
 188     {
 189         const struct group * const gr = getgrgid(statBuf->st_gid);
 190         const struct passwd * const pw = getpwuid(uid);
 191
 192         if (gr != NULL && pw != NULL) {
 193             char **user = gr->gr_mem;
 194             for ( ; *user != NULL; user++) {
 195                 if (strcmp(*user, pw->pw_name) == 0) {
 196                     if (mode & R_OK && !(statBuf->st_mode & S_IRGRP))
 197                         return "read not allowed by group";
 198                     if (mode & W_OK && !(statBuf->st_mode & S_IWGRP))
 199                         return "write not allowed by group";
 200                     if (mode & X_OK && !(statBuf->st_mode & S_IXGRP))
 201                         return "execute not allowed by group";
 202                     return NULL;
 203                 }
 204             }
 205         }
 206     }
 207
 208     /* That just leaves the other bits.. */
 209     if (mode & R_OK && !(statBuf->st_mode & S_IROTH))
 210         return "read not allowed";
 211     if (mode & W_OK && !(statBuf->st_mode & S_IWOTH))
 212         return "write not allowed";
 213     if (mode & X_OK && !(statBuf->st_mode & S_IXOTH))
 214         return "execute not allowed";
 215 #endif
 216
 217     return NULL;
 218 }
 219
 220
 221 /*******************************************************************************
 222  * Find a FastCGI server with a matching fs_path, and if fcgi_wrapper is
 223  * enabled with matching uid and gid.
 224  */
 225 fcgi_server *
 226 fcgi_util_fs_get_by_id(const char *ePath, uid_t uid, gid_t gid)
 227 {
 228     char path[FCGI_MAXPATH];
 229     fcgi_server *s;
 230
 231     /* @@@ This should now be done in the loop below */
 232     ap_cpystrn(path, ePath, FCGI_MAXPATH);
 233     ap_no2slash(path);
 234
 235     for (s = fcgi_servers; s != NULL; s = s->next) {
 236         int i;
 237         const char *fs_path = s->fs_path;
 238         for (i = 0; fs_path[i] && path[i]; ++i) {
 239             if (fs_path[i] != path[i]) {
 240                 break;
 241             }
 242         }
 243         if (fs_path[i]) {
 244             continue;
 245         }
 246         if (path[i] == '\0' || path[i] == '/') {
 247         if (fcgi_wrapper == NULL || (uid == s->uid && gid == s->gid))
 248             return s;
 249         }
 250     }
 251     return NULL;
 252 }
 253
 254 /*******************************************************************************
 255  * Find a FastCGI server with a matching fs_path, and if fcgi_wrapper is
 256  * enabled with matching user and group.
 257  */
 258 fcgi_server *
 259 fcgi_util_fs_get(const char *ePath, const char *user, const char *group)
 260 {
 261     char path[FCGI_MAXPATH];
 262     fcgi_server *s;
 263
 264     ap_cpystrn(path, ePath, FCGI_MAXPATH);
 265     ap_no2slash(path);
 266
 267     for (s = fcgi_servers; s != NULL; s = s->next) {
 268         if (strcmp(s->fs_path, path) == 0) {
 269             if (fcgi_wrapper == NULL)
 270                 return s;
 271
 272             if (strcmp(user, s->user) == 0
 273                 && (user[0] == '~' || strcmp(group, s->group) == 0))
 274             {
 275                 return s;
 276             }
 277         }
 278     }
 279     return NULL;
 280 }
 281
 282 const char *
 283 fcgi_util_fs_is_path_ok(pool * const p, const char * const fs_path,
 284         struct stat *finfo, const uid_t uid, const gid_t gid)
 285 {
 286     const char *err;
 287
 288     /* If a wrapper is in use, let the wrapper determine what it can
 289      * and can't execute */
 290     if (fcgi_wrapper)
 291         return NULL;
 292
 293     if (finfo == NULL) {
 294         finfo = (struct stat *)ap_palloc(p, sizeof(struct stat));
 295         if (stat(fs_path, finfo) < 0)
 296             return ap_psprintf(p, "stat() failed: %s", strerror(errno));
 297     }
 298
 299     /* No Parse Header scripts aren't allowed.
 300      * @@@ Well... we really could quite easily */
 301     if (strncmp(strrchr(fs_path, '/'), "/nph-", 5) == 0)
 302         return ap_psprintf(p, "NPH scripts cannot be run as FastCGI");
 303
 304     if (finfo->st_mode == 0)
 305         return ap_psprintf(p, "script not found or unable to stat()");
 306
 307     if (S_ISDIR(finfo->st_mode))
 308         return ap_psprintf(p, "script is a directory!");
 309
 310 #ifdef WIN32
 311     err = fcgi_util_check_access(p, fs_path, finfo, _S_IEXEC, fcgi_user_id, fcgi_group_id);
 312 #else
 313     err = fcgi_util_check_access(p, fs_path, finfo, X_OK, fcgi_user_id, fcgi_group_id);
 314 #endif
 315     if (err) {
 316         return ap_psprintf(p,
 317             "access for server (uid %ld, gid %ld) not allowed: %s",
 318             (long)fcgi_user_id, (long)fcgi_group_id, err);
 319     }
 320
 321     return NULL;
 322 }
 323
 324
 325 \f
 326 /*******************************************************************************
 327  * Allocate a new FastCGI server record from pool p with default values.
 328  */
 329 fcgi_server *
 330 fcgi_util_fs_new(pool *p)
 331 {
 332     fcgi_server *s = (fcgi_server *) ap_pcalloc(p, sizeof(fcgi_server));
 333
 334     /* Initialize anything who's init state is not zeroizzzzed */
 335     s->listenQueueDepth = FCGI_DEFAULT_LISTEN_Q;
 336     s->appConnectTimeout = FCGI_DEFAULT_APP_CONN_TIMEOUT;
 337     s->idle_timeout = FCGI_DEFAULT_IDLE_TIMEOUT;
 338     s->initStartDelay = DEFAULT_INIT_START_DELAY;
 339     s->restartDelay = FCGI_DEFAULT_RESTART_DELAY;
 340     s->restartOnExit = FALSE;
 341     s->directive = APP_CLASS_UNKNOWN;
 342     s->processPriority = FCGI_DEFAULT_PRIORITY;
 343 #ifdef WIN32
 344     s->listenFd = (int)INVALID_HANDLE_VALUE;
 345 #else
 346     s->listenFd = -2;
 347 #endif
 348     s->envp = &fcgi_empty_env;
 349
 350     return s;
 351 }
 352
 353 /*******************************************************************************
 354  * Add the server to the linked list of FastCGI servers.
 355  */
 356 void
 357 fcgi_util_fs_add(fcgi_server *s)
 358 {
 359     s->next = fcgi_servers;
 360     fcgi_servers = s;
 361 }
 362
 363 /*******************************************************************************
 364  * Configure uid, gid, user, group, username for wrapper.
 365  */
 366 const char *
 367 fcgi_util_fs_set_uid_n_gid(pool *p, fcgi_server *s, uid_t uid, gid_t gid)
 368 {
 369 #ifndef WIN32
 370     struct passwd *pw;
 371     struct group  *gr;
 372 #endif
 373
 374     if (fcgi_wrapper == NULL)
 375         return NULL;
 376
 377 #ifndef WIN32
 378     s->uid = uid;
 379     pw = getpwuid(uid);
 380     if (pw == NULL) {
 381         return ap_psprintf(p,
 382             "getpwuid() couldn't determine the username for uid '%ld', "
 383             "you probably need to modify the User directive: %s",
 384             (long)uid, strerror(errno));
 385     }
 386     s->user = ap_pstrdup(p, pw->pw_name);
 387     s->username = s->user;
 388
 389     s->gid = gid;
 390     gr = getgrgid(gid);
 391     if (gr == NULL) {
 392         return ap_psprintf(p,
 393             "getgrgid() couldn't determine the group name for gid '%ld', "
 394             "you probably need to modify the Group directive: %s",
 395             (long)gid, strerror(errno));
 396     }
 397     s->group = ap_pstrdup(p, gr->gr_name);
 398 #endif
 399     return NULL;
 400 }
 401
 402 /*******************************************************************************
 403  * Allocate an array of ServerProcess records.
 404  */
 405 ServerProcess *
 406 fcgi_util_fs_create_procs(pool *p, int num)
 407 {
 408     int i;
 409     ServerProcess *proc = (ServerProcess *)ap_pcalloc(p, sizeof(ServerProcess) * num);
 410
 411     for (i = 0; i < num; i++) {
 412 #ifdef WIN32
 413         proc[i].handle = INVALID_HANDLE_VALUE;
 414 #endif
 415         proc[i].pid = 0;
 416         proc[i].state = STATE_READY;
 417     }
 418     return proc;
 419 }
 420
 421 /*
 422  *----------------------------------------------------------------------
 423  *
 424  * fcgi_util_lock_fd
 425  *
 426  *      Provide file locking via fcntl(2) function call.  This
 427  *      code has been borrowed from Stevens "Advanced Unix
 428  *      Programming", page 370.
 429  *
 430  * Inputs:
 431  *      File descriptor to be locked, offsets within the file.
 432  *
 433  * Results:
 434  *      0 on successful locking, -1 otherwise
 435  *
 436  * Side effects:
 437  *      File pointed to by file descriptor is locked or unlocked.
 438  *      Provided macros allow for both blocking and non-blocking
 439  *      behavior.
 440  *
 441  *----------------------------------------------------------------------
 442  */
 443
 444 #ifndef WIN32
 445 int
 446 fcgi_util_lock_fd(int fd, int cmd, int type, off_t offset, int whence, off_t len)
 447 {
 448     int res = 0;
 449     struct flock lock;
 450
 451     lock.l_type = type;       /* F_RDLCK, F_WRLCK, F_UNLCK */
 452     lock.l_start = offset;    /* byte offset, relative to whence */
 453     lock.l_whence = whence;   /* SEEK_SET, SEET_CUR, SEEK_END */
 454     lock.l_len = len;         /* # of bytes, (0 indicates to EOF) */
 455
 456     /* Don't be fooled into thinking we've set a lock when we've
 457        merely caught a signal.  */
 458
 459     /* This is OK only if there is a hard_timeout() in effect! */
 460     while ((res = fcntl(fd, cmd, &lock)) == -1 && errno == EINTR);
 461     return res;
 462 }
 463 #endif
 464
 465 int fcgi_util_gettimeofday(struct timeval *Time) {
 466 #ifdef WIN32
 467     DWORD clock;
 468     time_t t;
 469
 470     clock = GetTickCount();
 471
 472     t = time(NULL);
 473
 474     Time->tv_sec = t; //clock / 1000;
 475     Time->tv_usec = (clock - Time->tv_sec) * 1000;
 476
 477     if (Time->tv_sec == (time_t)-1)
 478         return -1;
 479     else
 480         return 0;
 481 #else
 482     return gettimeofday(Time, NULL);
 483 #endif
 484 }
 485
 486 #ifdef WIN32
 487
 488 /*
 489  * We allow only one writer at a time and a writer can proceed only
 490  * when there are no readers.
 491  *
 492  * @@@ For named pipes we could lock only the process we're going to waste.
 493  */
 494
 495 FcgiRWLock * fcgi_rdwr_create()
 496 {
 497         FcgiRWLock *newlock = NULL;
 498
 499         newlock = (FcgiRWLock *) malloc(sizeof(FcgiRWLock));
 500         ap_assert(newlock);
 501
 502         newlock->write_lock = CreateEvent(NULL, FALSE, TRUE, NULL);
 503     newlock->mutex = CreateMutex(NULL, FALSE, NULL);
 504         newlock->counter = 0;
 505
 506         return newlock;
 507 }
 508
 509 void fcgi_rdwr_destroy(FcgiRWLock *lock)
 510 {
 511         CloseHandle(lock->write_lock);
 512     CloseHandle(lock->mutex);
 513         free(lock);
 514 }
 515
 516 int fcgi_rdwr_lock(FcgiRWLock *lock, int type)
 517 {
 518         if (type == WRITER)
 519     {
 520                 WaitForSingleObject(lock->write_lock, INFINITE);
 521     }
 522     else
 523     {
 524         WaitForSingleObject(lock->mutex, INFINITE);
 525         if (lock->counter == 0)
 526         {
 527                     WaitForSingleObject(lock->write_lock, INFINITE);
 528             }
 529         ++lock->counter;
 530         ReleaseMutex(lock->mutex);
 531     }
 532
 533         return 0;
 534 }
 535
 536 int fcgi_rdwr_unlock(FcgiRWLock *lock, int type)
 537 {
 538         if (type == WRITER)
 539     {
 540         SetEvent(lock->write_lock);
 541     }
 542     else
 543     {
 544         WaitForSingleObject(lock->mutex, INFINITE);
 545         --lock->counter;
 546         if (lock->counter == 0)
 547         {
 548                     SetEvent(lock->write_lock);
 549         }
 550         ReleaseMutex(lock->mutex);
 551     }
 552
 553         return 0;
 554 }
 555
 556 int fcgi_rdwr_try_lock(FcgiRWLock *lock, int type)
 557 {
 558     DWORD rc;
 559
 560         if (type == WRITER)
 561     {
 562                 rc = WaitForSingleObject(lock->write_lock, 0);
 563         if (rc == WAIT_TIMEOUT || rc == WAIT_FAILED)
 564         {
 565             return -1;
 566         }
 567     }
 568     else
 569     {
 570         ap_assert(0);
 571     }
 572
 573     return 0;
 574 }
 575
 576 #endif