lib/libc/net/getservbyport_r.c

   1 /*      $NetBSD: getservbyport_r.c,v 1.7 2010/04/25 00:54:46 joerg Exp $        */
   2
   3 /*
   4  * Copyright (c) 1983, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #if defined(LIBC_SCCS) && !defined(lint)
  34 #if 0
  35 static char sccsid[] = "@(#)getservbyport.c     8.1 (Berkeley) 6/4/93";
  36 #else
  37 __RCSID("$NetBSD: getservbyport_r.c,v 1.7 2010/04/25 00:54:46 joerg Exp $");
  38 #endif
  39 #endif /* LIBC_SCCS and not lint */
  40
  41 #include "namespace.h"
  42 #include <cdbr.h>
  43 #include <netdb.h>
  44 #include <string.h>
  45 #include <stdlib.h>
  46
  47 #include "servent.h"
  48
  49 #ifdef __weak_alias
  50 __weak_alias(getservbyport_r,_getservbyport_r)
  51 #endif
  52
  53 static struct servent *
  54 _servent_getbyport(struct servent_data *sd, struct servent *sp, int port,
  55     const char *proto)
  56 {
  57
  58         if ((sd->flags & (_SV_CDB | _SV_PLAINFILE)) == 0)
  59                 return NULL;
  60
  61         if (sd->flags & _SV_CDB) {
  62                 uint8_t buf[255 + 4];
  63                 size_t protolen;
  64                 const uint8_t *data;
  65                 const void *data_ptr;
  66                 size_t datalen;
  67
  68                 port = be16toh(port);
  69
  70                 if (proto != NULL && *proto == '\0')
  71                         return NULL;
  72                 if (proto != NULL)
  73                         protolen = strlen(proto);
  74                 else
  75                         protolen = 0;
  76                 if (port < 0 || port > 65536)
  77                         return NULL;
  78
  79                 buf[0] = 0;
  80                 buf[1] = protolen;
  81                 be16enc(buf + 2, port);
  82                 memcpy(buf + 4, proto, protolen);
  83
  84                 if (cdbr_find(sd->cdb, buf, 4 + protolen,
  85                     &data_ptr, &datalen))
  86                         return NULL;
  87
  88                 if (datalen < protolen + 4)
  89                         return NULL;
  90
  91                 data = data_ptr;
  92                 if (be16dec(data) != port)
  93                         return NULL;
  94                 if (protolen) {
  95                         if (data[2] != protolen)
  96                                 return NULL;
  97                         if (memcmp(data + 3, proto, protolen + 1))
  98                                 return NULL;
  99                 }
 100                 return _servent_parsedb(sd, sp, data, datalen);
 101         } else {
 102                 while (_servent_getline(sd) != -1) {
 103                         if (_servent_parseline(sd, sp) == NULL)
 104                                 continue;
 105                         if (sp->s_port != port)
 106                                 continue;
 107                         if (proto == NULL || strcmp(sp->s_proto, proto) == 0)
 108                                 return sp;
 109                 }
 110                 return NULL;
 111         }
 112 }
 113
 114 struct servent *
 115 getservbyport_r(int port, const char *proto, struct servent *sp,
 116     struct servent_data *sd)
 117 {
 118         setservent_r(sd->flags & _SV_STAYOPEN, sd);
 119         sp = _servent_getbyport(sd, sp, port, proto);
 120         if (!(sd->flags & _SV_STAYOPEN))
 121                 _servent_close(sd);
 122         return sp;
 123 }