src/acl/Arp.cc

   1 /*
   2  * DEBUG: section 28    Access Control
   3  * AUTHOR: Duane Wessels
   4  *
   5  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   6  * ----------------------------------------------------------
   7  *
   8  *  Squid is the result of efforts by numerous individuals from
   9  *  the Internet community; see the CONTRIBUTORS file for full
  10  *  details.   Many organizations have provided support for Squid's
  11  *  development; see the SPONSORS file for full details.  Squid is
  12  *  Copyrighted (C) 2001 by the Regents of the University of
  13  *  California; see the COPYRIGHT file for full details.  Squid
  14  *  incorporates software developed and/or copyrighted by other
  15  *  sources; see the CREDITS file for full details.
  16  *
  17  *  This program is free software; you can redistribute it and/or modify
  18  *  it under the terms of the GNU General Public License as published by
  19  *  the Free Software Foundation; either version 2 of the License, or
  20  *  (at your option) any later version.
  21  *
  22  *  This program is distributed in the hope that it will be useful,
  23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25  *  GNU General Public License for more details.
  26  *
  27  *  You should have received a copy of the GNU General Public License
  28  *  along with this program; if not, write to the Free Software
  29  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  30  *
  31  *
  32  * Copyright (c) 2003, Robert Collins <robertc@squid-cache.org>
  33  */
  34
  35 #include "squid.h"
  36
  37 #if USE_SQUID_EUI
  38
  39 #include "acl/Arp.h"
  40 #include "acl/FilledChecklist.h"
  41 #include "Debug.h"
  42 #include "eui/Eui48.h"
  43 #include "ip/Address.h"
  44 #include "protos.h"
  45 #include "wordlist.h"
  46
  47 static void aclParseArpList(SplayNode<Eui::Eui48 *> **curlist);
  48 static int aclMatchArp(SplayNode<Eui::Eui48 *> **dataptr, Ip::Address &c);
  49 static SplayNode<Eui::Eui48 *>::SPLAYCMP aclArpCompare;
  50 static SplayNode<Eui::Eui48 *>::SPLAYWALKEE aclDumpArpListWalkee;
  51
  52 ACL *
  53 ACLARP::clone() const
  54 {
  55     return new ACLARP(*this);
  56 }
  57
  58 ACLARP::ACLARP (char const *theClass) : data (NULL), class_ (theClass)
  59 {}
  60
  61 ACLARP::ACLARP (ACLARP const & old) : data (NULL), class_ (old.class_)
  62 {
  63     /* we don't have copy constructors for the data yet */
  64     assert (!old.data);
  65 }
  66
  67 ACLARP::~ACLARP()
  68 {
  69     if (data)
  70         data->destroy(SplayNode<Eui::Eui48*>::DefaultFree);
  71 }
  72
  73 char const *
  74 ACLARP::typeString() const
  75 {
  76     return class_;
  77 }
  78
  79 bool
  80 ACLARP::empty () const
  81 {
  82     return data->empty();
  83 }
  84
  85 /* ==== BEGIN ARP ACL SUPPORT ============================================= */
  86
  87 /*
  88  * From:    dale@server.ctam.bitmcnit.bryansk.su (Dale)
  89  * To:      wessels@nlanr.net
  90  * Subject: Another Squid patch... :)
  91  * Date:    Thu, 04 Dec 1997 19:55:01 +0300
  92  * ============================================================================
  93  *
  94  * Working on setting up a proper firewall for a network containing some
  95  * Win'95 computers at our Univ, I've discovered that some smart students
  96  * avoid the restrictions easily just changing their IP addresses in Win'95
  97  * Contol Panel... It has been getting boring, so I took Squid-1.1.18
  98  * sources and added a new acl type for hard-wired access control:
  99  *
 100  * acl <name> arp <Ethernet address> ...
 101  *
 102  * For example,
 103  *
 104  * acl students arp 00:00:21:55:ed:22 00:00:21:ff:55:38
 105  *
 106  * NOTE: Linux code by David Luyer <luyer@ucs.uwa.edu.au>.
 107  *       Original (BSD-specific) code no longer works.
 108  *       Solaris code by R. Gancarz <radekg@solaris.elektrownia-lagisza.com.pl>
 109  */
 110
 111 Eui::Eui48 *
 112 aclParseArpData(const char *t)
 113 {
 114     char buf[256];
 115     Eui::Eui48 *q = new Eui::Eui48;
 116     debugs(28, 5, "aclParseArpData: " << t);
 117
 118     if (sscanf(t, "%[0-9a-fA-F:]", buf) != 1) {
 119         debugs(28, DBG_CRITICAL, "aclParseArpData: Bad ethernet address: '" << t << "'");
 120         safe_free(q);
 121         return NULL;
 122     }
 123
 124     if (!q->decode(buf)) {
 125         debugs(28, DBG_CRITICAL, "" << cfg_filename << " line " << config_lineno << ": " << config_input_line);
 126         debugs(28, DBG_CRITICAL, "aclParseArpData: Ignoring invalid ARP acl entry: can't parse '" << buf << "'");
 127         safe_free(q);
 128         return NULL;
 129     }
 130
 131     return q;
 132 }
 133
 134 /*******************/
 135 /* aclParseArpList */
 136 /*******************/
 137 void
 138 ACLARP::parse()
 139 {
 140     aclParseArpList(&data);
 141 }
 142
 143 void
 144 aclParseArpList(SplayNode<Eui::Eui48 *> **curlist)
 145 {
 146     char *t = NULL;
 147     SplayNode<Eui::Eui48*> **Top = curlist;
 148     Eui::Eui48 *q = NULL;
 149
 150     while ((t = strtokFile())) {
 151         if ((q = aclParseArpData(t)) == NULL)
 152             continue;
 153
 154         *Top = (*Top)->insert(q, aclArpCompare);
 155     }
 156 }
 157
 158 int
 159 ACLARP::match(ACLChecklist *cl)
 160 {
 161     ACLFilledChecklist *checklist = Filled(cl);
 162
 163     /* IPv6 does not do ARP */
 164     if (!checklist->src_addr.IsIPv4()) {
 165         debugs(14, 3, "ACLARP::match: IPv4 Required for ARP Lookups. Skipping " << checklist->src_addr );
 166         return 0;
 167     }
 168
 169     return aclMatchArp(&data, checklist->src_addr);
 170 }
 171
 172 /***************/
 173 /* aclMatchArp */
 174 /***************/
 175 int
 176 aclMatchArp(SplayNode<Eui::Eui48 *> **dataptr, Ip::Address &c)
 177 {
 178     Eui::Eui48 result;
 179     SplayNode<Eui::Eui48 *> **Top = dataptr;
 180
 181     if (result.lookup(c)) {
 182         /* Do ACL match lookup */
 183         *Top = (*Top)->splay(&result, aclArpCompare);
 184         debugs(28, 3, "aclMatchArp: '" << c << "' " << (splayLastResult ? "NOT found" : "found"));
 185         return (0 == splayLastResult);
 186     }
 187
 188     /*
 189      * Address was not found on any interface
 190      */
 191     debugs(28, 3, "aclMatchArp: " << c << " NOT found");
 192     return 0;
 193 }
 194
 195 static int
 196 aclArpCompare(Eui::Eui48 * const &a, Eui::Eui48 * const &b)
 197 {
 198     return memcmp(a, b, sizeof(Eui::Eui48));
 199 }
 200
 201 static void
 202 aclDumpArpListWalkee(Eui::Eui48 * const &node, void *state)
 203 {
 204     static char buf[48];
 205     node->encode(buf, 48);
 206     wordlistAdd((wordlist **)state, buf);
 207 }
 208
 209 wordlist *
 210 ACLARP::dump() const
 211 {
 212     wordlist *w = NULL;
 213     data->walk(aclDumpArpListWalkee, &w);
 214     return w;
 215 }
 216
 217 /* ==== END ARP ACL SUPPORT =============================================== */
 218
 219 #endif /* USE_SQUID_EUI */