/* * libtins is a net packet wrapper library for crafting and * interpreting sniffed packets. * * Copyright (C) 2011 Nasel * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef TINS_ARP_H #define TINS_ARP_H #include #include "pdu.h" #include "ipaddress.h" #include "endianness.h" #include "hwaddress.h" #include "network_interface.h" namespace Tins { /** * \brief Class that represents an ARP PDU. * */ class ARP : public PDU { public: /** * The type of the hardware address. */ typedef HWAddress<6> hwaddress_type; /** * The type of the IP address. */ typedef IPv4Address ipaddress_type; /** * \brief This PDU's flag. */ static const PDU::PDUType pdu_flag = PDU::ARP; /** * \brief Enum which indicates the type of ARP packet. */ enum Flags { REQUEST = 0x0001, REPLY = 0x0002 }; /** * \brief Default constructor for ARP PDU objects. * * ARP requests and replies can be constructed easily using * ARP::make_arp_request/reply static functions. */ ARP(ipaddress_type target_ip = ipaddress_type(), ipaddress_type sender_ip = ipaddress_type(), const hwaddress_type &target_hw = hwaddress_type(), const hwaddress_type &sender_hw = hwaddress_type()); /** * \brief Constructor which creates an ARP object from a buffer and adds all identifiable * PDUs found in the buffer as children of this one. * \param buffer The buffer from which this PDU will be constructed. * \param total_sz The total size of the buffer. */ ARP(const uint8_t *buffer, uint32_t total_sz); /* Getters */ /** * \brief Getter for the sender's hardware address. * * \return Returns the sender's hardware address in an uint8_t*. */ hwaddress_type sender_hw_addr() const { return _arp.ar_sha; } /** * \brief Getter for the sender's IP address. * * \return Returns the sender's IP address in an uint32_t. */ ipaddress_type sender_ip_addr() const { return ipaddress_type(_arp.ar_sip); } /** * \brief Getter for the target's hardware address. * * \return Returns the target's hardware address in an uint8_t*. */ hwaddress_type target_hw_addr() const { return _arp.ar_tha; } /** * \brief Getter for the target's IP address. * * \return Returns the target's IP address in an uint32_t. */ ipaddress_type target_ip_addr() const { return ipaddress_type(_arp.ar_tip); } /** * \brief Getter for the hardware address format. * * \return Returns the hardware address' format in an uint16_t. */ uint16_t hw_addr_format() const { return Endian::be_to_host(_arp.ar_hrd); } /** * \brief Getter for the protocol address format. * * \return Returns the protocol address' format in an uint16_t. */ uint16_t prot_addr_format() const { return Endian::be_to_host(_arp.ar_pro); } /** * \brief Getter for the hardware address length. * * \return Returns the hardware address' length in an uint8_t. */ uint8_t hw_addr_length() const { return _arp.ar_hln; } /** * \brief Getter for the protocol address length. * * \return Returns the protocol address' length in an uint8_t. */ uint8_t prot_addr_length() const { return _arp.ar_pln; } /** * \brief Getter for the ARP opcode. * * \return Returns the ARP opcode in an uint16_t. */ uint16_t opcode() const { return Endian::be_to_host(_arp.ar_op); } /** \brief Getter for the header size. * \return Returns the ARP header size. * \sa PDU::header_size */ uint32_t header_size() const; /* Setters */ /** * \brief Setter for the sender's hardware address. * * \param new_snd_hw_addr uint8_t array containing the new sender's hardware address. */ void sender_hw_addr(const hwaddress_type &new_snd_hw_addr); /** * \brief Setter for the sender's IP address. * * \param new_snd_ip_addr IPv4Address containing the new sender's IP address. */ void sender_ip_addr(ipaddress_type new_snd_ip_addr); /** * \brief Setter for the target's hardware address. * * \param new_tgt_hw_addr uint8_t array containing the new target's hardware address. */ void target_hw_addr(const hwaddress_type &new_tgt_hw_addr); /** * \brief Setter for the target's IP address. * * \param new_tgt_ip_addr IPv4Address containing the new target's IP address. */ void target_ip_addr(ipaddress_type new_tgt_ip_addr); /** * \brief Setter for the hardware address format. * * \param new_hw_addr_fmt uint16_t with the new hardware address' format. */ void hw_addr_format(uint16_t new_hw_addr_fmt); /** * \brief Setter for the protocol address format. * * \param new_prot_addr_fmt uint16_t with the new protocol address' format. */ void prot_addr_format(uint16_t new_prot_addr_fmt); /** * \brief Setter for the hardware address length. * * \param new_hw_addr_len uint8_t with the new hardware address' length. */ void hw_addr_length(uint8_t new_hw_addr_len); /** * \brief Setter for the protocol address length. * * \param new_prot_addr_len uint8_t with the new protocol address' length. */ void prot_addr_length(uint8_t new_prot_addr_len); /** * \brief Setter for the ARP opcode. * * \param new_opcode Flag enum value of the ARP opcode to set. */ void opcode(Flags new_opcode); /** * \brief Getter for the PDU's type. * \sa PDU::pdu_type */ PDUType pdu_type() const { return PDU::ARP; } /** * \brief Creates an ARP Request within a Layer 2 PDU using uint32_t for target and sender. * * Creates an ARP Request PDU and embeds it within a Layer 2 PDU ready to be * sent. The target and sender's protocol address are given using uint32_t. * * \param iface string with the interface from where to send the ARP. * \param target IPv4Address with the target's IP. * \param sender IPv4Address with the sender's IP. * \param hw_snd uint8_t array of 6 bytes containing the sender's hardware address. * \return Returns a PDU* to the new Layer 2 PDU containing the ARP Request. */ static PDU* make_arp_request(const NetworkInterface& iface, ipaddress_type target, ipaddress_type sender, const hwaddress_type &hw_snd = hwaddress_type()); /** * \brief Creates an ARP Reply within a Layer 2 PDU using uint32_t for target and sender. * * Creates an ARP Reply PDU and embeds it within a Layer 2 PDU ready to be * sent. The target and sender's protocol address are given using uint32_t. * * \param iface string with the interface from where to send the ARP. * \param target IPv4Address with the target's IP. * \param sender IPv4Address with the sender's IP. * \param hw_tgt uint8_t array of 6 bytes containing the target's hardware address. * \param hw_snd uint8_t array of 6 bytes containing the sender's hardware address. * \return Returns a PDU* to the new Layer 2 PDU containing the ARP Replay. */ static PDU* make_arp_reply(const NetworkInterface& iface, ipaddress_type target, ipaddress_type sender, const hwaddress_type &hw_tgt = hwaddress_type(), const hwaddress_type &hw_snd = hwaddress_type()); /** \brief Check wether ptr points to a valid response for this PDU. * * \sa PDU::matches_response * \param ptr The pointer to the buffer. * \param total_sz The size of the buffer. */ bool matches_response(uint8_t *ptr, uint32_t total_sz); /** \brief Clones this pdu, filling the corresponding header with data * extracted from a buffer. * * \param ptr The pointer to the from from which the data will be extracted. * \param total_sz The size of the buffer. * \return The cloned PDU. * \sa PDU::clone_packet */ PDU *clone_packet(const uint8_t *ptr, uint32_t total_sz); /** * \sa PDU::clone_pdu */ PDU *clone_pdu() const { return do_clone_pdu(); } private: struct arphdr { uint16_t ar_hrd; /* format of hardware address */ uint16_t ar_pro; /* format of protocol address */ uint8_t ar_hln; /* length of hardware address */ uint8_t ar_pln; /* length of protocol address */ uint16_t ar_op; /* ARP opcode (command) */ /* sender hardware address */ uint8_t ar_sha[hwaddress_type::address_size]; /* sender IP address */ uint32_t ar_sip; /* target hardware address */ uint8_t ar_tha[hwaddress_type::address_size]; /* target IP address */ uint32_t ar_tip; } __attribute__((__packed__)); void write_serialization(uint8_t *buffer, uint32_t total_sz, const PDU *parent); arphdr _arp; }; }; #endif //TINS_ARP_H