hesiod/nss_hesiod/hesiod-proto.c

   1 /* Copyright (C) 1997-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Mark Kettenis <kettenis@phys.uva.nl>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <hesiod.h>
  21 #include <netdb.h>
  22 #include <netinet/in.h>
  23 #include <nss.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include "nss_hesiod.h"
  29
  30 /* Declare a parser for Hesiod protocol entries.  Although the format
  31    of the entries is identical to those in /etc/protocols, here is no
  32    predefined parser for us to use.  */
  33
  34 #define ENTNAME protoent
  35
  36 struct protoent_data {};
  37
  38 #define TRAILING_LIST_MEMBER            p_aliases
  39 #define TRAILING_LIST_SEPARATOR_P       isspace
  40 #include <nss/nss_files/files-parse.c>
  41 LINE_PARSER
  42 ("#",
  43  STRING_FIELD (result->p_name, isspace, 1);
  44  INT_FIELD (result->p_proto, isspace, 1, 10,);
  45  )
  46
  47 enum nss_status
  48 _nss_hesiod_setprotoent (int stayopen)
  49 {
  50   return NSS_STATUS_SUCCESS;
  51 }
  52
  53 enum nss_status
  54 _nss_hesiod_endprotoent (void)
  55 {
  56   return NSS_STATUS_SUCCESS;
  57 }
  58
  59 static enum nss_status
  60 lookup (const char *name, const char *type, struct protoent *proto,
  61         char *buffer, size_t buflen, int *errnop)
  62 {
  63   struct parser_data *data = (void *) buffer;
  64   size_t linebuflen;
  65   void *context;
  66   char **list, **item;
  67   int parse_res;
  68   int found;
  69   int olderr = errno;
  70
  71   context = _nss_hesiod_init ();
  72   if (context == NULL)
  73     return NSS_STATUS_UNAVAIL;
  74
  75   list = hesiod_resolve (context, name, type);
  76   if (list == NULL)
  77     {
  78       int err = errno;
  79       hesiod_end (context);
  80       __set_errno (olderr);
  81       return err == ENOENT ? NSS_STATUS_NOTFOUND : NSS_STATUS_UNAVAIL;
  82     }
  83
  84   linebuflen = buffer + buflen - data->linebuffer;
  85
  86   item = list;
  87   found = 0;
  88   do
  89     {
  90       size_t len = strlen (*item) + 1;
  91
  92       if (linebuflen < len)
  93         {
  94           hesiod_free_list (context, list);
  95           hesiod_end (context);
  96           *errnop = ERANGE;
  97           return NSS_STATUS_TRYAGAIN;
  98         }
  99
 100       memcpy (data->linebuffer, *item, len);
 101
 102       parse_res = parse_line (buffer, proto, data, buflen, errnop);
 103       if (parse_res == -1)
 104         {
 105           hesiod_free_list (context, list);
 106           hesiod_end (context);
 107           return NSS_STATUS_TRYAGAIN;
 108         }
 109
 110       if (parse_res > 0)
 111         found = 1;
 112
 113       ++item;
 114     }
 115   while (*item != NULL && !found);
 116
 117   hesiod_free_list (context, list);
 118   hesiod_end (context);
 119
 120   if (found == 0)
 121     {
 122       __set_errno (olderr);
 123       return NSS_STATUS_NOTFOUND;
 124     }
 125
 126   return NSS_STATUS_SUCCESS;
 127 }
 128
 129 enum nss_status
 130 _nss_hesiod_getprotobyname_r (const char *name, struct protoent *proto,
 131                               char *buffer, size_t buflen, int *errnop)
 132 {
 133   return lookup (name, "protocol", proto, buffer, buflen, errnop);
 134 }
 135
 136 enum nss_status
 137 _nss_hesiod_getprotobynumber_r (const int protocol, struct protoent *proto,
 138                                 char *buffer, size_t buflen, int *errnop)
 139 {
 140   char protostr[21];
 141
 142   snprintf (protostr, sizeof protostr, "%d", protocol);
 143
 144   return lookup (protostr, "protonum", proto, buffer, buflen, errnop);
 145 }