libtins/src/internals.cpp

/*
 * Copyright (c) 2012, Matias Fontanini
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following disclaimer
 *   in the documentation and/or other materials provided with the
 *   distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include "internals.h"
#include "ip.h"
#include "ethernetII.h"
#include "ieee802_3.h"
#include "radiotap.h"
#include "dot11/dot11_base.h"
#include "ipv6.h"
#include "arp.h"
#include "eapol.h"
#include "rawpdu.h"
#include "dot1q.h"
#include "pppoe.h"
#include "ip_address.h"
#include "ipv6_address.h"

using std::string;

namespace Tins {
namespace Internals {
bool from_hex(const string &str, uint32_t &result) {
    unsigned i(0);
    result = 0;
    while(i < str.size()) {
        uint8_t tmp;
        if(str[i] >= 'A' && str[i] <= 'F')
            tmp = (str[i] - 'A' + 10);
        else if(str[i] >= '0' && str[i] <= '9')
            tmp = (str[i] - '0');
        else
            return false;
        result = (result << 4) | tmp;
        i++;
    }
    return true;
}

void skip_line(std::istream &input) {
    int c = 0;
    while(c != '\n' && input)
         c = input.get();
}

Tins::PDU *pdu_from_flag(Constants::Ethernet::e flag, const uint8_t *buffer, 
  uint32_t size, bool rawpdu_on_no_match) 
{
    switch(flag) {
        case Tins::Constants::Ethernet::IP:
            return new Tins::IP(buffer, size);
        case Constants::Ethernet::IPV6:
            return new Tins::IPv6(buffer, size);
        case Tins::Constants::Ethernet::ARP:
            return new Tins::ARP(buffer, size);
        case Tins::Constants::Ethernet::PPPOED:
            return new Tins::PPPoE(buffer, size);
        case Tins::Constants::Ethernet::EAPOL:
            return Tins::EAPOL::from_bytes(buffer, size);
        case Tins::Constants::Ethernet::VLAN:
            return new Tins::Dot1Q(buffer, size);
        default:
            return rawpdu_on_no_match ? new RawPDU(buffer, size) : 0;
    };
}

Tins::PDU *pdu_from_flag(PDU::PDUType type, const uint8_t *buffer, uint32_t size) 
{
    switch(type) {
        case Tins::PDU::ETHERNET_II:
            return new Tins::EthernetII(buffer, size);
        case Tins::PDU::IP:
            return new Tins::IP(buffer, size);
        case Tins::PDU::IPv6:
            return new Tins::IPv6(buffer, size);
        case Tins::PDU::ARP:
            return new Tins::ARP(buffer, size);
        case Tins::PDU::IEEE802_3:
            return new Tins::IEEE802_3(buffer, size);
        case Tins::PDU::RADIOTAP:
            return new Tins::RadioTap(buffer, size);
        case Tins::PDU::PPPOE:
            return new Tins::PPPoE(buffer, size);
        case Tins::PDU::DOT11:
        case Tins::PDU::DOT11_ACK:
        case Tins::PDU::DOT11_ASSOC_REQ:
        case Tins::PDU::DOT11_ASSOC_RESP:
        case Tins::PDU::DOT11_AUTH:
        case Tins::PDU::DOT11_BEACON:
        case Tins::PDU::DOT11_BLOCK_ACK:
        case Tins::PDU::DOT11_BLOCK_ACK_REQ:
        case Tins::PDU::DOT11_CF_END:
        case Tins::PDU::DOT11_DATA:
        case Tins::PDU::DOT11_CONTROL:
        case Tins::PDU::DOT11_DEAUTH:
        case Tins::PDU::DOT11_DIASSOC:
        case Tins::PDU::DOT11_END_CF_ACK:
        case Tins::PDU::DOT11_MANAGEMENT:
        case Tins::PDU::DOT11_PROBE_REQ:
        case Tins::PDU::DOT11_PROBE_RESP:
        case Tins::PDU::DOT11_PS_POLL:
        case Tins::PDU::DOT11_REASSOC_REQ:
        case Tins::PDU::DOT11_REASSOC_RESP:
        case Tins::PDU::DOT11_RTS:
        case Tins::PDU::DOT11_QOS_DATA:
            return Tins::Dot11::from_bytes(buffer, size);
        default:
            return 0;
    };
}

Constants::Ethernet::e pdu_flag_to_ether_type(PDU::PDUType flag) {
    switch (flag) {
        case PDU::IP:
            return Constants::Ethernet::IP;
        case PDU::IPv6:
            return Constants::Ethernet::IPV6;
        case PDU::ARP:
            return Constants::Ethernet::ARP;
        case PDU::DOT1Q:
            return Constants::Ethernet::VLAN;
        case PDU::PPPOE:
            return Constants::Ethernet::PPPOED;
        default:
            return Constants::Ethernet::UNKNOWN;
    }
}

bool increment(IPv4Address &addr) {
    uint32_t addr_int = Endian::be_to_host<uint32_t>(addr);
    bool reached_end = ++addr_int == 0xffffffff;
    addr = IPv4Address(Endian::be_to_host<uint32_t>(addr_int));
    return reached_end;
}

bool increment(IPv6Address &addr) {
    IPv6Address::iterator it = addr.end() - 1;
    while(it >= addr.begin() && *it == 0xff) {
        *it = 0;
        --it;
    }
    // reached end
    if(it < addr.begin())
        return true;
    (*it)++;
    return false;
}

bool decrement(IPv4Address &addr) {
    uint32_t addr_int = Endian::be_to_host<uint32_t>(addr);
    bool reached_end = --addr_int == 0;
    addr = IPv4Address(Endian::be_to_host<uint32_t>(addr_int));
    return reached_end;
}

bool decrement(IPv6Address &addr) {
    IPv6Address::iterator it = addr.end() - 1;
    while(it >= addr.begin() && *it == 0) {
        *it = 0xff;
        --it;
    }
    // reached end
    if(it < addr.begin())
        return true;
    (*it)--;
    return false;
}
} // namespace Internals
} // namespace Tins