package/uhttpd/src/uhttpd-utils.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd - Utility functions
   3  *
   4  *   Copyright (C) 2010 Jo-Philipp Wich <xm@subsignal.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #define _XOPEN_SOURCE 500       /* crypt() */
  20 #define _BSD_SOURCE                     /* strcasecmp(), strncasecmp() */
  21
  22 #include "uhttpd.h"
  23 #include "uhttpd-utils.h"
  24
  25 #ifdef HAVE_TLS
  26 #include "uhttpd-tls.h"
  27 #endif
  28
  29
  30 static char *uh_index_files[] = {
  31         "index.html",
  32         "index.htm",
  33         "default.html",
  34         "default.htm"
  35 };
  36
  37
  38 const char * sa_straddr(void *sa)
  39 {
  40         static char str[INET6_ADDRSTRLEN];
  41         struct sockaddr_in *v4 = (struct sockaddr_in *)sa;
  42         struct sockaddr_in6 *v6 = (struct sockaddr_in6 *)sa;
  43
  44         if( v4->sin_family == AF_INET )
  45                 return inet_ntop(AF_INET, &(v4->sin_addr), str, sizeof(str));
  46         else
  47                 return inet_ntop(AF_INET6, &(v6->sin6_addr), str, sizeof(str));
  48 }
  49
  50 const char * sa_strport(void *sa)
  51 {
  52         static char str[6];
  53         snprintf(str, sizeof(str), "%i", sa_port(sa));
  54         return str;
  55 }
  56
  57 int sa_port(void *sa)
  58 {
  59         return ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
  60 }
  61
  62 /* Simple strstr() like function that takes len arguments for both haystack and needle. */
  63 char *strfind(char *haystack, int hslen, const char *needle, int ndlen)
  64 {
  65         int match = 0;
  66         int i, j;
  67
  68         for( i = 0; i < hslen; i++ )
  69         {
  70                 if( haystack[i] == needle[0] )
  71                 {
  72                         match = ((ndlen == 1) || ((i + ndlen) <= hslen));
  73
  74                         for( j = 1; (j < ndlen) && ((i + j) < hslen); j++ )
  75                         {
  76                                 if( haystack[i+j] != needle[j] )
  77                                 {
  78                                         match = 0;
  79                                         break;
  80                                 }
  81                         }
  82
  83                         if( match )
  84                                 return &haystack[i];
  85                 }
  86         }
  87
  88         return NULL;
  89 }
  90
  91 /* interruptable select() */
  92 int select_intr(int n, fd_set *r, fd_set *w, fd_set *e, struct timeval *t)
  93 {
  94         int rv;
  95         sigset_t ssn, sso;
  96
  97         /* unblock SIGCHLD */
  98         sigemptyset(&ssn);
  99         sigaddset(&ssn, SIGCHLD);
 100         sigprocmask(SIG_UNBLOCK, &ssn, &sso);
 101
 102         rv = select(n, r, w, e, t);
 103
 104         /* restore signal mask */
 105         sigprocmask(SIG_SETMASK, &sso, NULL);
 106
 107         return rv;
 108 }
 109
 110
 111 int uh_tcp_send(struct client *cl, const char *buf, int len)
 112 {
 113         fd_set writer;
 114         struct timeval timeout;
 115
 116         FD_ZERO(&writer);
 117         FD_SET(cl->socket, &writer);
 118
 119         timeout.tv_sec = 0;
 120         timeout.tv_usec = 500000;
 121
 122         if( select(cl->socket + 1, NULL, &writer, NULL, &timeout) > 0 )
 123         {
 124 #ifdef HAVE_TLS
 125                 if( cl->tls )
 126                         return cl->server->conf->tls_send(cl, (void *)buf, len);
 127                 else
 128 #endif
 129                         return send(cl->socket, buf, len, 0);
 130         }
 131
 132         return -1;
 133 }
 134
 135 int uh_tcp_peek(struct client *cl, char *buf, int len)
 136 {
 137         int sz = uh_tcp_recv(cl, buf, len);
 138
 139         /* store received data in peek buffer */
 140         if( sz > 0 )
 141         {
 142                 cl->peeklen = sz;
 143                 memcpy(cl->peekbuf, buf, sz);
 144         }
 145
 146         return sz;
 147 }
 148
 149 int uh_tcp_recv(struct client *cl, char *buf, int len)
 150 {
 151         int sz = 0;
 152         int rsz = 0;
 153
 154         /* first serve data from peek buffer */
 155         if( cl->peeklen > 0 )
 156         {
 157                 sz = min(cl->peeklen, len);
 158                 len -= sz; cl->peeklen -= sz;
 159
 160                 memcpy(buf, cl->peekbuf, sz);
 161                 memmove(cl->peekbuf, &cl->peekbuf[sz], cl->peeklen);
 162         }
 163
 164         /* caller wants more */
 165         if( len > 0 )
 166         {
 167 #ifdef HAVE_TLS
 168                 if( cl->tls )
 169                         rsz = cl->server->conf->tls_recv(cl, (void *)&buf[sz], len);
 170                 else
 171 #endif
 172                         rsz = recv(cl->socket, (void *)&buf[sz], len, 0);
 173
 174                 if( (sz == 0) || (rsz > 0) )
 175                         sz += rsz;
 176         }
 177
 178         return sz;
 179 }
 180
 181 #define ensure(x) \
 182         do { if( x < 0 ) return -1; } while(0)
 183
 184 int uh_http_sendhf(struct client *cl, int code, const char *summary, const char *fmt, ...)
 185 {
 186         va_list ap;
 187
 188         char buffer[UH_LIMIT_MSGHEAD];
 189         int len;
 190
 191         len = snprintf(buffer, sizeof(buffer),
 192                 "HTTP/1.1 %03i %s\r\n"
 193                 "Connection: close\r\n"
 194                 "Content-Type: text/plain\r\n"
 195                 "Transfer-Encoding: chunked\r\n\r\n",
 196                         code, summary
 197         );
 198
 199         ensure(uh_tcp_send(cl, buffer, len));
 200
 201         va_start(ap, fmt);
 202         len = vsnprintf(buffer, sizeof(buffer), fmt, ap);
 203         va_end(ap);
 204
 205         ensure(uh_http_sendc(cl, buffer, len));
 206         ensure(uh_http_sendc(cl, NULL, 0));
 207
 208         return 0;
 209 }
 210
 211
 212 int uh_http_sendc(struct client *cl, const char *data, int len)
 213 {
 214         char chunk[8];
 215         int clen;
 216
 217         if( len == -1 )
 218                 len = strlen(data);
 219
 220         if( len > 0 )
 221         {
 222                 clen = snprintf(chunk, sizeof(chunk), "%X\r\n", len);
 223                 ensure(uh_tcp_send(cl, chunk, clen));
 224                 ensure(uh_tcp_send(cl, data, len));
 225                 ensure(uh_tcp_send(cl, "\r\n", 2));
 226         }
 227         else
 228         {
 229                 ensure(uh_tcp_send(cl, "0\r\n\r\n", 5));
 230         }
 231
 232         return 0;
 233 }
 234
 235 int uh_http_sendf(
 236         struct client *cl, struct http_request *req, const char *fmt, ...
 237 ) {
 238         va_list ap;
 239         char buffer[UH_LIMIT_MSGHEAD];
 240         int len;
 241
 242         va_start(ap, fmt);
 243         len = vsnprintf(buffer, sizeof(buffer), fmt, ap);
 244         va_end(ap);
 245
 246         if( (req != NULL) && (req->version > 1.0) )
 247                 ensure(uh_http_sendc(cl, buffer, len));
 248         else if( len > 0 )
 249                 ensure(uh_tcp_send(cl, buffer, len));
 250
 251         return 0;
 252 }
 253
 254 int uh_http_send(
 255         struct client *cl, struct http_request *req, const char *buf, int len
 256 ) {
 257         if( len < 0 )
 258                 len = strlen(buf);
 259
 260         if( (req != NULL) && (req->version > 1.0) )
 261                 ensure(uh_http_sendc(cl, buf, len));
 262         else if( len > 0 )
 263                 ensure(uh_tcp_send(cl, buf, len));
 264
 265         return 0;
 266 }
 267
 268
 269 int uh_urldecode(char *buf, int blen, const char *src, int slen)
 270 {
 271         int i;
 272         int len = 0;
 273
 274 #define hex(x) \
 275         (((x) <= '9') ? ((x) - '0') : \
 276                 (((x) <= 'F') ? ((x) - 'A' + 10) : \
 277                         ((x) - 'a' + 10)))
 278
 279         for( i = 0; (i <= slen) && (i <= blen); i++ )
 280         {
 281                 if( src[i] == '%' )
 282                 {
 283                         if( ((i+2) <= slen) && isxdigit(src[i+1]) && isxdigit(src[i+2]) )
 284                         {
 285                                 buf[len++] = (char)(16 * hex(src[i+1]) + hex(src[i+2]));
 286                                 i += 2;
 287                         }
 288                         else
 289                         {
 290                                 buf[len++] = '%';
 291                         }
 292                 }
 293                 else
 294                 {
 295                         buf[len++] = src[i];
 296                 }
 297         }
 298
 299         return len;
 300 }
 301
 302 int uh_urlencode(char *buf, int blen, const char *src, int slen)
 303 {
 304         int i;
 305         int len = 0;
 306         const char hex[] = "0123456789abcdef";
 307
 308         for( i = 0; (i <= slen) && (i <= blen); i++ )
 309         {
 310                 if( isalnum(src[i]) || (src[i] == '-') || (src[i] == '_') ||
 311                     (src[i] == '.') || (src[i] == '~') )
 312                 {
 313                         buf[len++] = src[i];
 314                 }
 315                 else if( (len+3) <= blen )
 316                 {
 317                         buf[len++] = '%';
 318                         buf[len++] = hex[(src[i] >> 4) & 15];
 319                         buf[len++] = hex[(src[i] & 15) & 15];
 320                 }
 321                 else
 322                 {
 323                         break;
 324                 }
 325         }
 326
 327         return len;
 328 }
 329
 330 int uh_b64decode(char *buf, int blen, const unsigned char *src, int slen)
 331 {
 332         int i = 0;
 333         int len = 0;
 334
 335         unsigned int cin  = 0;
 336         unsigned int cout = 0;
 337
 338
 339         for( i = 0; (i <= slen) && (src[i] != 0); i++ )
 340         {
 341                 cin = src[i];
 342
 343                 if( (cin >= '0') && (cin <= '9') )
 344                         cin = cin - '0' + 52;
 345                 else if( (cin >= 'A') && (cin <= 'Z') )
 346                         cin = cin - 'A';
 347                 else if( (cin >= 'a') && (cin <= 'z') )
 348                         cin = cin - 'a' + 26;
 349                 else if( cin == '+' )
 350                         cin = 62;
 351                 else if( cin == '/' )
 352                         cin = 63;
 353                 else if( cin == '=' )
 354                         cin = 0;
 355                 else
 356                         continue;
 357
 358                 cout = (cout << 6) | cin;
 359
 360                 if( (i % 4) == 3 )
 361                 {
 362                         if( (len + 3) < blen )
 363                         {
 364                                 buf[len++] = (char)(cout >> 16);
 365                                 buf[len++] = (char)(cout >> 8);
 366                                 buf[len++] = (char)(cout);
 367                         }
 368                         else
 369                         {
 370                                 break;
 371                         }
 372                 }
 373         }
 374
 375         buf[len++] = 0;
 376         return len;
 377 }
 378
 379
 380 struct path_info * uh_path_lookup(struct client *cl, const char *url)
 381 {
 382         static char path_phys[PATH_MAX];
 383         static char path_info[PATH_MAX];
 384         static struct path_info p;
 385
 386         char buffer[UH_LIMIT_MSGHEAD];
 387         char *docroot = cl->server->conf->docroot;
 388         char *pathptr = NULL;
 389
 390         int i = 0;
 391         struct stat s;
 392
 393
 394         memset(path_phys, 0, sizeof(path_phys));
 395         memset(path_info, 0, sizeof(path_info));
 396         memset(buffer, 0, sizeof(buffer));
 397         memset(&p, 0, sizeof(p));
 398
 399         /* copy docroot */
 400         memcpy(buffer, docroot,
 401                 min(strlen(docroot), sizeof(buffer) - 1));
 402
 403         /* separate query string from url */
 404         if( (pathptr = strchr(url, '?')) != NULL )
 405         {
 406                 p.query = pathptr[1] ? pathptr + 1 : NULL;
 407
 408                 /* urldecode component w/o query */
 409                 if( pathptr > url )
 410                         uh_urldecode(
 411                                 &buffer[strlen(docroot)],
 412                                 sizeof(buffer) - strlen(docroot) - 1,
 413                                 url, (int)(pathptr - url) - 1
 414                         );
 415         }
 416
 417         /* no query string, decode all of url */
 418         else
 419         {
 420                 uh_urldecode(
 421                         &buffer[strlen(docroot)],
 422                         sizeof(buffer) - strlen(docroot) - 1,
 423                         url, strlen(url)
 424                 );
 425         }
 426
 427         /* create canon path */
 428         for( i = strlen(buffer); i >= 0; i-- )
 429         {
 430                 if( (buffer[i] == 0) || (buffer[i] == '/') )
 431                 {
 432                         memset(path_info, 0, sizeof(path_info));
 433                         memcpy(path_info, buffer, min(i + 1, sizeof(path_info) - 1));
 434
 435                         if( realpath(path_info, path_phys) )
 436                         {
 437                                 memset(path_info, 0, sizeof(path_info));
 438                                 memcpy(path_info, &buffer[i],
 439                                         min(strlen(buffer) - i, sizeof(path_info) - 1));
 440
 441                                 break;
 442                         }
 443                 }
 444         }
 445
 446         /* check whether found path is within docroot */
 447         if( strncmp(path_phys, docroot, strlen(docroot)) ||
 448             ((path_phys[strlen(docroot)] != 0) &&
 449                  (path_phys[strlen(docroot)] != '/'))
 450         ) {
 451                 return NULL;
 452         }
 453
 454         /* test current path */
 455         if( ! stat(path_phys, &p.stat) )
 456         {
 457                 /* is a regular file */
 458                 if( p.stat.st_mode & S_IFREG )
 459                 {
 460                         p.root = docroot;
 461                         p.phys = path_phys;
 462                         p.name = &path_phys[strlen(docroot)];
 463                         p.info = path_info[0] ? path_info : NULL;
 464                 }
 465
 466                 /* is a directory */
 467                 else if( (p.stat.st_mode & S_IFDIR) && !strlen(path_info) )
 468                 {
 469                         /* ensure trailing slash */
 470                         if( path_phys[strlen(path_phys)-1] != '/' )
 471                                 path_phys[strlen(path_phys)] = '/';
 472
 473                         /* try to locate index file */
 474                         memset(buffer, 0, sizeof(buffer));
 475                         memcpy(buffer, path_phys, sizeof(buffer));
 476                         pathptr = &buffer[strlen(buffer)];
 477
 478                         for( i = 0; i < array_size(uh_index_files); i++ )
 479                         {
 480                                 strncat(buffer, uh_index_files[i], sizeof(buffer));
 481
 482                                 if( !stat(buffer, &s) && (s.st_mode & S_IFREG) )
 483                                 {
 484                                         memcpy(path_phys, buffer, sizeof(path_phys));
 485                                         memcpy(&p.stat, &s, sizeof(p.stat));
 486                                         break;
 487                                 }
 488
 489                                 *pathptr = 0;
 490                         }
 491
 492                         p.root = docroot;
 493                         p.phys = path_phys;
 494                         p.name = &path_phys[strlen(docroot)];
 495                 }
 496         }
 497
 498         return p.phys ? &p : NULL;
 499 }
 500
 501
 502 static char uh_realms[UH_LIMIT_AUTHREALMS * sizeof(struct auth_realm)] = { 0 };
 503 static int uh_realm_count = 0;
 504
 505 struct auth_realm * uh_auth_add(char *path, char *user, char *pass)
 506 {
 507         struct auth_realm *new = NULL;
 508         struct passwd *pwd;
 509         struct spwd *spwd;
 510
 511         if( uh_realm_count < UH_LIMIT_AUTHREALMS )
 512         {
 513                 new = (struct auth_realm *)
 514                         &uh_realms[uh_realm_count * sizeof(struct auth_realm)];
 515
 516                 memset(new, 0, sizeof(struct auth_realm));
 517
 518                 memcpy(new->path, path,
 519                         min(strlen(path), sizeof(new->path) - 1));
 520
 521                 memcpy(new->user, user,
 522                         min(strlen(user), sizeof(new->user) - 1));
 523
 524                 /* given password refers to a passwd entry */
 525                 if( (strlen(pass) > 3) && !strncmp(pass, "$p$", 3) )
 526                 {
 527                         /* try to resolve shadow entry */
 528                         if( ((spwd = getspnam(&pass[3])) != NULL) && spwd->sp_pwdp )
 529                         {
 530                                 memcpy(new->pass, spwd->sp_pwdp,
 531                                         min(strlen(spwd->sp_pwdp), sizeof(new->pass) - 1));
 532                         }
 533
 534                         /* try to resolve passwd entry */
 535                         else if( ((pwd = getpwnam(&pass[3])) != NULL) && pwd->pw_passwd &&
 536                                 (pwd->pw_passwd[0] != '!') && (pwd->pw_passwd[0] != 0)
 537                         ) {
 538                                 memcpy(new->pass, pwd->pw_passwd,
 539                                         min(strlen(pwd->pw_passwd), sizeof(new->pass) - 1));
 540                         }
 541                 }
 542
 543                 /* ordinary pwd */
 544                 else
 545                 {
 546                         memcpy(new->pass, pass,
 547                                 min(strlen(pass), sizeof(new->pass) - 1));
 548                 }
 549
 550                 uh_realm_count++;
 551         }
 552
 553         return new;
 554 }
 555
 556 int uh_auth_check(
 557         struct client *cl, struct http_request *req, struct path_info *pi
 558 ) {
 559         int i, plen, rlen, protected;
 560         char buffer[UH_LIMIT_MSGHEAD];
 561         char *user = NULL;
 562         char *pass = NULL;
 563
 564         struct auth_realm *realm = NULL;
 565
 566         plen = strlen(pi->name);
 567         protected = 0;
 568
 569         /* check whether at least one realm covers the requested url */
 570         for( i = 0; i < uh_realm_count; i++ )
 571         {
 572                 realm = (struct auth_realm *)
 573                         &uh_realms[i * sizeof(struct auth_realm)];
 574
 575                 rlen = strlen(realm->path);
 576
 577                 if( (plen >= rlen) && !strncasecmp(pi->name, realm->path, rlen) )
 578                 {
 579                         req->realm = realm;
 580                         protected = 1;
 581                         break;
 582                 }
 583         }
 584
 585         /* requested resource is covered by a realm */
 586         if( protected )
 587         {
 588                 /* try to get client auth info */
 589                 foreach_header(i, req->headers)
 590                 {
 591                         if( !strcasecmp(req->headers[i], "Authorization") &&
 592                                 (strlen(req->headers[i+1]) > 6) &&
 593                                 !strncasecmp(req->headers[i+1], "Basic ", 6)
 594                         ) {
 595                                 memset(buffer, 0, sizeof(buffer));
 596                                 uh_b64decode(buffer, sizeof(buffer) - 1,
 597                                         (unsigned char *) &req->headers[i+1][6],
 598                                         strlen(req->headers[i+1]) - 6);
 599
 600                                 if( (pass = strchr(buffer, ':')) != NULL )
 601                                 {
 602                                         user = buffer;
 603                                         *pass++ = 0;
 604                                 }
 605
 606                                 break;
 607                         }
 608                 }
 609
 610                 /* have client auth */
 611                 if( user && pass )
 612                 {
 613                         /* find matching realm */
 614                         for( i = 0, realm = NULL; i < uh_realm_count; i++ )
 615                         {
 616                                 realm = (struct auth_realm *)
 617                                         &uh_realms[i * sizeof(struct auth_realm)];
 618
 619                                 rlen = strlen(realm->path);
 620
 621                                 if( (plen >= rlen) &&
 622                                     !strncasecmp(pi->name, realm->path, rlen) &&
 623                                     !strcmp(user, realm->user)
 624                                 ) {
 625                                         req->realm = realm;
 626                                         break;
 627                                 }
 628
 629                                 realm = NULL;
 630                         }
 631
 632                         /* found a realm matching the username */
 633                         if( realm )
 634                         {
 635                                 /* is a crypt passwd */
 636                                 if( realm->pass[0] == '$' )
 637                                         pass = crypt(pass, realm->pass);
 638
 639                                 /* check user pass */
 640                                 if( !strcmp(pass, realm->pass) )
 641                                         return 1;
 642                         }
 643                 }
 644
 645                 /* 401 */
 646                 uh_http_sendf(cl, NULL,
 647                         "HTTP/%.1f 401 Authorization Required\r\n"
 648                         "WWW-Authenticate: Basic realm=\"%s\"\r\n"
 649                         "Content-Type: text/plain\r\n"
 650                         "Content-Length: 23\r\n\r\n"
 651                         "Authorization Required\n",
 652                                 req->version, cl->server->conf->realm
 653                 );
 654
 655                 return 0;
 656         }
 657
 658         return 1;
 659 }
 660
 661
 662 static char uh_listeners[UH_LIMIT_LISTENERS * sizeof(struct listener)] = { 0 };
 663 static char uh_clients[UH_LIMIT_CLIENTS * sizeof(struct client)] = { 0 };
 664
 665 static int uh_listener_count = 0;
 666 static int uh_client_count = 0;
 667
 668
 669 struct listener * uh_listener_add(int sock, struct config *conf)
 670 {
 671         struct listener *new = NULL;
 672         socklen_t sl;
 673
 674         if( uh_listener_count < UH_LIMIT_LISTENERS )
 675         {
 676                 new = (struct listener *)
 677                         &uh_listeners[uh_listener_count * sizeof(struct listener)];
 678
 679                 new->socket = sock;
 680                 new->conf   = conf;
 681
 682                 /* get local endpoint addr */
 683                 sl = sizeof(struct sockaddr_in6);
 684                 memset(&(new->addr), 0, sl);
 685                 getsockname(sock, (struct sockaddr *) &(new->addr), &sl);
 686
 687                 uh_listener_count++;
 688         }
 689
 690         return new;
 691 }
 692
 693 struct listener * uh_listener_lookup(int sock)
 694 {
 695         struct listener *cur = NULL;
 696         int i;
 697
 698         for( i = 0; i < uh_listener_count; i++ )
 699         {
 700                 cur = (struct listener *) &uh_listeners[i * sizeof(struct listener)];
 701
 702                 if( cur->socket == sock )
 703                         return cur;
 704         }
 705
 706         return NULL;
 707 }
 708
 709
 710 struct client * uh_client_add(int sock, struct listener *serv)
 711 {
 712         struct client *new = NULL;
 713         socklen_t sl;
 714
 715         if( uh_client_count < UH_LIMIT_CLIENTS )
 716         {
 717                 new = (struct client *)
 718                         &uh_clients[uh_client_count * sizeof(struct client)];
 719
 720                 new->socket = sock;
 721                 new->server = serv;
 722
 723                 /* get remote endpoint addr */
 724                 sl = sizeof(struct sockaddr_in6);
 725                 memset(&(new->peeraddr), 0, sl);
 726                 getpeername(sock, (struct sockaddr *) &(new->peeraddr), &sl);
 727
 728                 /* get local endpoint addr */
 729                 sl = sizeof(struct sockaddr_in6);
 730                 memset(&(new->servaddr), 0, sl);
 731                 getsockname(sock, (struct sockaddr *) &(new->servaddr), &sl);
 732
 733                 uh_client_count++;
 734         }
 735
 736         return new;
 737 }
 738
 739 struct client * uh_client_lookup(int sock)
 740 {
 741         struct client *cur = NULL;
 742         int i;
 743
 744         for( i = 0; i < uh_client_count; i++ )
 745         {
 746                 cur = (struct client *) &uh_clients[i * sizeof(struct client)];
 747
 748                 if( cur->socket == sock )
 749                         return cur;
 750         }
 751
 752         return NULL;
 753 }
 754
 755 void uh_client_remove(int sock)
 756 {
 757         struct client *del = uh_client_lookup(sock);
 758
 759         if( del )
 760         {
 761                 memmove(del, del + 1,
 762                         sizeof(uh_clients) - (int)((char *)del - uh_clients) - sizeof(struct client));
 763
 764                 uh_client_count--;
 765         }
 766 }
 767
 768