src/acl/Arp.cc

   1 /*
   2  * Copyright (C) 1996-2014 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 /* DEBUG: section 28    Access Control */
  10
  11 #include "squid.h"
  12
  13 #if USE_SQUID_EUI
  14
  15 #include "acl/Arp.h"
  16 #include "acl/FilledChecklist.h"
  17 #include "cache_cf.h"
  18 #include "Debug.h"
  19 #include "eui/Eui48.h"
  20 #include "globals.h"
  21 #include "ip/Address.h"
  22
  23 static void aclParseArpList(Splay<Eui::Eui48 *> **curlist);
  24 static int aclMatchArp(Splay<Eui::Eui48 *> **dataptr, Ip::Address &c);
  25 static Splay<Eui::Eui48 *>::SPLAYCMP aclArpCompare;
  26
  27 ACL *
  28 ACLARP::clone() const
  29 {
  30     return new ACLARP(*this);
  31 }
  32
  33 ACLARP::ACLARP (char const *theClass) : data (NULL), class_ (theClass)
  34 {}
  35
  36 ACLARP::ACLARP (ACLARP const & old) : data (NULL), class_ (old.class_)
  37 {
  38     /* we don't have copy constructors for the data yet */
  39     assert (!old.data);
  40 }
  41
  42 ACLARP::~ACLARP()
  43 {
  44     if (data)
  45         data->destroy();
  46 }
  47
  48 char const *
  49 ACLARP::typeString() const
  50 {
  51     return class_;
  52 }
  53
  54 bool
  55 ACLARP::empty () const
  56 {
  57     return data->empty();
  58 }
  59
  60 /* ==== BEGIN ARP ACL SUPPORT ============================================= */
  61
  62 /*
  63  * From:    dale@server.ctam.bitmcnit.bryansk.su (Dale)
  64  * To:      wessels@nlanr.net
  65  * Subject: Another Squid patch... :)
  66  * Date:    Thu, 04 Dec 1997 19:55:01 +0300
  67  * ============================================================================
  68  *
  69  * Working on setting up a proper firewall for a network containing some
  70  * Win'95 computers at our Univ, I've discovered that some smart students
  71  * avoid the restrictions easily just changing their IP addresses in Win'95
  72  * Contol Panel... It has been getting boring, so I took Squid-1.1.18
  73  * sources and added a new acl type for hard-wired access control:
  74  *
  75  * acl <name> arp <Ethernet address> ...
  76  *
  77  * For example,
  78  *
  79  * acl students arp 00:00:21:55:ed:22 00:00:21:ff:55:38
  80  *
  81  * NOTE: Linux code by David Luyer <luyer@ucs.uwa.edu.au>.
  82  *       Original (BSD-specific) code no longer works.
  83  *       Solaris code by R. Gancarz <radekg@solaris.elektrownia-lagisza.com.pl>
  84  */
  85
  86 Eui::Eui48 *
  87 aclParseArpData(const char *t)
  88 {
  89     char buf[256];
  90     Eui::Eui48 *q = new Eui::Eui48;
  91     debugs(28, 5, "aclParseArpData: " << t);
  92
  93     if (sscanf(t, "%[0-9a-fA-F:]", buf) != 1) {
  94         debugs(28, DBG_CRITICAL, "aclParseArpData: Bad ethernet address: '" << t << "'");
  95         safe_free(q);
  96         return NULL;
  97     }
  98
  99     if (!q->decode(buf)) {
 100         debugs(28, DBG_CRITICAL, "" << cfg_filename << " line " << config_lineno << ": " << config_input_line);
 101         debugs(28, DBG_CRITICAL, "aclParseArpData: Ignoring invalid ARP acl entry: can't parse '" << buf << "'");
 102         safe_free(q);
 103         return NULL;
 104     }
 105
 106     return q;
 107 }
 108
 109 /*******************/
 110 /* aclParseArpList */
 111 /*******************/
 112 void
 113 ACLARP::parse()
 114 {
 115     aclParseArpList(&data);
 116 }
 117
 118 void
 119 aclParseArpList(Splay<Eui::Eui48 *> **curlist)
 120 {
 121     char *t = NULL;
 122     Eui::Eui48 *q = NULL;
 123
 124     while ((t = strtokFile())) {
 125         if ((q = aclParseArpData(t)) == NULL)
 126             continue;
 127
 128         (*curlist)->insert(q, aclArpCompare);
 129     }
 130 }
 131
 132 int
 133 ACLARP::match(ACLChecklist *cl)
 134 {
 135     ACLFilledChecklist *checklist = Filled(cl);
 136
 137     /* IPv6 does not do ARP */
 138     if (!checklist->src_addr.isIPv4()) {
 139         debugs(14, 3, "ACLARP::match: IPv4 Required for ARP Lookups. Skipping " << checklist->src_addr );
 140         return 0;
 141     }
 142
 143     return aclMatchArp(&data, checklist->src_addr);
 144 }
 145
 146 /***************/
 147 /* aclMatchArp */
 148 /***************/
 149 int
 150 aclMatchArp(Splay<Eui::Eui48 *> **dataptr, Ip::Address &c)
 151 {
 152     Eui::Eui48 lookingFor;
 153     if (lookingFor.lookup(c)) {
 154         Eui::Eui48 * const* lookupResult;
 155         lookupResult = (*dataptr)->find(&lookingFor,aclArpCompare);
 156         debugs(28, 3, "aclMatchArp: '" << c << "' " << (lookupResult ? "found" : "NOT found"));
 157         return (lookupResult != NULL);
 158     }
 159     debugs(28, 3, "aclMatchArp: " << c << " NOT found");
 160     return 0;
 161 }
 162
 163 static int
 164 aclArpCompare(Eui::Eui48 * const &a, Eui::Eui48 * const &b)
 165 {
 166     return memcmp(a, b, sizeof(Eui::Eui48));
 167 }
 168
 169 // visitor functor to collect the contents of the Arp Acl
 170 struct ArpAclDumpVisitor {
 171     SBufList contents;
 172     void operator() (const Eui::Eui48 * v) {
 173         static char buf[48];
 174         v->encode(buf,48);
 175         contents.push_back(SBuf(buf));
 176     }
 177 };
 178
 179 SBufList
 180 ACLARP::dump() const
 181 {
 182     ArpAclDumpVisitor visitor;
 183     data->visit(visitor);
 184     return visitor.contents;
 185 }
 186
 187 /* ==== END ARP ACL SUPPORT =============================================== */
 188
 189 #endif /* USE_SQUID_EUI */
 190