src/base/inet.cc

   1 /*
   2  * Copyright (c) 2002-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Nathan Binkert
  29  */
  30
  31 #include <cstdio>
  32 #include <sstream>
  33 #include <string>
  34
  35 #include "base/cprintf.hh"
  36 #include "base/inet.hh"
  37 #include "base/types.hh"
  38
  39 using namespace std;
  40 namespace Net {
  41
  42 EthAddr::EthAddr()
  43 {
  44     memset(data, 0, ETH_ADDR_LEN);
  45 }
  46
  47 EthAddr::EthAddr(const uint8_t ea[ETH_ADDR_LEN])
  48 {
  49     *data = *ea;
  50 }
  51
  52 EthAddr::EthAddr(const eth_addr &ea)
  53 {
  54     *data = *ea.data;
  55 }
  56
  57 EthAddr::EthAddr(const std::string &addr)
  58 {
  59     parse(addr);
  60 }
  61
  62 const EthAddr &
  63 EthAddr::operator=(const eth_addr &ea)
  64 {
  65     *data = *ea.data;
  66     return *this;
  67 }
  68
  69 const EthAddr &
  70 EthAddr::operator=(const std::string &addr)
  71 {
  72     parse(addr);
  73     return *this;
  74 }
  75
  76 void
  77 EthAddr::parse(const std::string &addr)
  78 {
  79     // the hack below is to make sure that ETH_ADDR_LEN is 6 otherwise
  80     // the sscanf function won't work.
  81     int bytes[ETH_ADDR_LEN == 6 ? ETH_ADDR_LEN : -1];
  82     if (sscanf(addr.c_str(), "%x:%x:%x:%x:%x:%x", &bytes[0], &bytes[1],
  83                &bytes[2], &bytes[3], &bytes[4], &bytes[5]) != ETH_ADDR_LEN) {
  84         memset(data, 0xff, ETH_ADDR_LEN);
  85         return;
  86     }
  87
  88     for (int i = 0; i < ETH_ADDR_LEN; ++i) {
  89         if (bytes[i] & ~0xff) {
  90             memset(data, 0xff, ETH_ADDR_LEN);
  91             return;
  92         }
  93
  94         data[i] = bytes[i];
  95     }
  96 }
  97
  98 string
  99 EthAddr::string() const
 100 {
 101     stringstream stream;
 102     stream << *this;
 103     return stream.str();
 104 }
 105
 106 bool
 107 operator==(const EthAddr &left, const EthAddr &right)
 108 {
 109     return memcmp(left.bytes(), right.bytes(), ETH_ADDR_LEN);
 110 }
 111
 112 ostream &
 113 operator<<(ostream &stream, const EthAddr &ea)
 114 {
 115     const uint8_t *a = ea.addr();
 116     ccprintf(stream, "%x:%x:%x:%x:%x:%x", a[0], a[1], a[2], a[3], a[4], a[5]);
 117     return stream;
 118 }
 119
 120 uint16_t
 121 cksum(const IpPtr &ptr)
 122 {
 123     int sum = ip_cksum_add(ptr->bytes(), ptr->hlen(), 0);
 124     return ip_cksum_carry(sum);
 125 }
 126
 127 uint16_t
 128 __tu_cksum(const IpPtr &ip)
 129 {
 130     int tcplen = ip->len() - ip->hlen();
 131     int sum = ip_cksum_add(ip->payload(), tcplen, 0);
 132     sum = ip_cksum_add(&ip->ip_src, 8, sum); // source and destination
 133     sum += htons(ip->ip_p + tcplen);
 134     return ip_cksum_carry(sum);
 135 }
 136
 137 uint16_t
 138 cksum(const TcpPtr &tcp)
 139 { return __tu_cksum(IpPtr(tcp.packet())); }
 140
 141 uint16_t
 142 cksum(const UdpPtr &udp)
 143 { return __tu_cksum(IpPtr(udp.packet())); }
 144
 145 bool
 146 IpHdr::options(vector<const IpOpt *> &vec) const
 147 {
 148     vec.clear();
 149
 150     const uint8_t *data = bytes() + sizeof(struct ip_hdr);
 151     int all = hlen() - sizeof(struct ip_hdr);
 152     while (all > 0) {
 153         const IpOpt *opt = (const IpOpt *)data;
 154         int len = opt->len();
 155         if (all < len)
 156             return false;
 157
 158         vec.push_back(opt);
 159         all -= len;
 160         data += len;
 161     }
 162
 163     return true;
 164 }
 165
 166 bool
 167 TcpHdr::options(vector<const TcpOpt *> &vec) const
 168 {
 169     vec.clear();
 170
 171     const uint8_t *data = bytes() + sizeof(struct tcp_hdr);
 172     int all = off() - sizeof(struct tcp_hdr);
 173     while (all > 0) {
 174         const TcpOpt *opt = (const TcpOpt *)data;
 175         int len = opt->len();
 176         if (all < len)
 177             return false;
 178
 179         vec.push_back(opt);
 180         all -= len;
 181         data += len;
 182     }
 183
 184     return true;
 185 }
 186
 187 bool
 188 TcpOpt::sack(vector<SackRange> &vec) const
 189 {
 190     vec.clear();
 191
 192     const uint8_t *data = bytes() + sizeof(struct tcp_hdr);
 193     int all = len() - offsetof(tcp_opt, opt_data.sack);
 194     while (all > 0) {
 195         const uint16_t *sack = (const uint16_t *)data;
 196         int len = sizeof(uint16_t) * 2;
 197         if (all < len) {
 198             vec.clear();
 199             return false;
 200         }
 201
 202         vec.push_back(RangeIn(ntohs(sack[0]), ntohs(sack[1])));
 203         all -= len;
 204         data += len;
 205     }
 206
 207     return false;
 208 }
 209
 210 int
 211 hsplit(const EthPacketPtr &ptr)
 212 {
 213     int split_point = 0;
 214
 215     IpPtr ip(ptr);
 216     if (ip) {
 217         split_point = ip.pstart();
 218
 219         TcpPtr tcp(ip);
 220         if (tcp)
 221             split_point = tcp.pstart();
 222
 223         UdpPtr udp(ip);
 224         if (udp)
 225             split_point = udp.pstart();
 226     }
 227     return split_point;
 228 }
 229
 230
 231 /* namespace Net */ }