/* * Copyright (c) 2017, 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. * */ #ifndef TINS_ICMP_H #define TINS_ICMP_H // Windows likes to define macros with not-so-common-names, which break // this code #ifdef _WIN32 #ifdef TIMESTAMP_REQUEST #undef TIMESTAMP_REQUEST #endif // TIMESTAMP_REQUEST #ifdef TIMESTAMP_REPLY #undef TIMESTAMP_REPLY #endif // TIMESTAMP_REPLY #endif // _WIN32 #include #include #include #include #include namespace Tins { namespace Memory { class InputMemoryStream; } // Memory /** * \class ICMP * \brief Class that represents an ICMP PDU. * * ICMP is the representation of the ICMP PDU. Instances of this class * must be sent over a level 3 PDU, this will otherwise fail. */ class TINS_API ICMP : public PDU { public: /** * \brief This PDU's flag. */ static const PDU::PDUType pdu_flag = PDU::ICMP; /** * The type used to store addresses. */ typedef IPv4Address address_type; /** \brief ICMP flags */ enum Flags { ECHO_REPLY = 0, DEST_UNREACHABLE = 3, SOURCE_QUENCH = 4, REDIRECT = 5, ECHO_REQUEST = 8, TIME_EXCEEDED = 11, PARAM_PROBLEM = 12, TIMESTAMP_REQUEST = 13, TIMESTAMP_REPLY = 14, INFO_REQUEST = 15, INFO_REPLY = 16, ADDRESS_MASK_REQUEST = 17, ADDRESS_MASK_REPLY = 18, EXTENDED_ECHO_REQUEST = 42, EXTENDED_ECHO_REPLY = 43 }; /** * \brief Extracts metadata for this protocol based on the buffer provided * * \param buffer Pointer to a buffer * \param total_sz Size of the buffer pointed by buffer */ static metadata extract_metadata(const uint8_t *buffer, uint32_t total_sz); /** * \brief Creates an instance of ICMP. * * If no flag is specified, then ECHO_REQUEST will be used. * \param flag The type flag which will be set. */ ICMP(Flags flag = ECHO_REQUEST); /** * \brief Constructs an ICMP object from a buffer. * * If there is not enough size for an ICMP header, a * malformed_packet exception is thrown. * * Any extra data in the buffer will be stored in a RawPDU. * * \param buffer The buffer from which this PDU will be constructed. * \param total_sz The total size of the buffer. */ ICMP(const uint8_t* buffer, uint32_t total_sz); /** * \brief Sets the code field. * * \param new_code The code which will be stored in the ICMP struct. */ void code(uint8_t new_code); /** \brief Sets the type field. * * \param type The type which will be stored in the ICMP struct. */ void type(Flags type); /** * \brief Setter for the id field. * * \param new_id uint16_t with the new id. */ void id(uint16_t new_id); /** * \brief Setter for the sequence field. * * \param new_seq uint16_t with the new sequence. */ void sequence(uint16_t new_seq); /** * \brief Setter for the gateway field. * * \param new_gw The new value for the gateway field. */ void gateway(address_type new_gw); /** * \brief Setter for the mtu field. * * \param new_mtu uint16_t with the new sequence. */ void mtu(uint16_t new_mtu); /** * \brief Setter for the pointer field. * * \param new_pointer uint8_t with the new pointer. */ void pointer(uint8_t new_pointer); /** * \brief Setter for the original timestamp field. * * \param new_timestamp the value to be set. */ void original_timestamp(uint32_t new_timestamp); /** * \brief Setter for the receive timestamp field. * * \param new_timestamp the value to be set. */ void receive_timestamp(uint32_t new_timestamp); /** * \brief Setter for the transmit timestamp field. * * \param new_timestamp the value to be set. */ void transmit_timestamp(uint32_t new_timestamp); /** * \brief Setter for the address mask field. * * \param new_mask the value to be set. */ void address_mask(address_type new_mask); /** * \brief Sets echo request flag for this PDU. * * \param id The identifier for this request. * \param seq The sequence number for this request. */ void set_echo_request(uint16_t id, uint16_t seq); /** * \brief Sets echo reply flag for this PDU. * * \param id The identifier for this request. * \param seq The sequence number for this request. */ void set_echo_reply(uint16_t id, uint16_t seq); /** * \brief Sets information request flag for this PDU. * * \param id The identifier for this request. * \param seq The sequence number for this request. */ void set_info_request(uint16_t id, uint16_t seq); /** * \brief Sets information reply flag for this PDU. * * \param id The identifier for this request. * \param seq The sequence number for this request. */ void set_info_reply(uint16_t id, uint16_t seq); /** * \brief Sets destination unreachable for this PDU. */ void set_dest_unreachable(); /** * \brief Sets time exceeded flag for this PDU. * * \param ttl_exceeded If true this PDU will represent a ICMP ttl * exceeded, otherwise it will represent a fragment reassembly * time exceeded. */ void set_time_exceeded(bool ttl_exceeded = true); /** * \brief Sets parameter problem flag for this PDU. * * \param set_pointer Indicates whether a pointer to the bad octet * is provided. * \param bad_octet Identifies the octet in which the error was * detected. If set_pointer == false, it is ignored. */ void set_param_problem(bool set_pointer = false, uint8_t bad_octet = 0); /** * \brief Sets source quench flag for this PDU. */ void set_source_quench(); /** * \brief Sets redirect flag for this PDU. * * \param icode The code to be set. * \param address Address of the gateway to which traffic should * be sent. */ void set_redirect(uint8_t icode, address_type address); /** * \brief Getter for the ICMP type flag. * * \return The type flag for this ICMP PDU. */ Flags type() const { return (Flags)header_.type; } /** * \brief Getter for the ICMP code flag. * * \return The code flag for this ICMP PDU. */ uint8_t code() const { return header_.code; } /** * \brief Getter for the checksum field. * * \return Returns the checksum as an unit16_t. */ uint16_t checksum() const { return Endian::be_to_host(header_.check); } /** * \brief Getter for the echo id. * * \return Returns the echo id. */ uint16_t id() const { return Endian::be_to_host(header_.un.echo.id); } /** * \brief Getter for the echo sequence number. * * \return Returns the echo sequence number. */ uint16_t sequence() const { return Endian::be_to_host(header_.un.echo.sequence); } /** * \brief Getter for the gateway field. * * \return Returns the gateway field value. */ address_type gateway() const { return address_type(header_.un.gateway); } /** * \brief Getter for the pointer field. * * \return Returns the pointer field value. */ uint8_t pointer() const { return header_.un.rfc4884.pointer; } /** * \brief Getter for the length field. * * \return Returns the length field value. */ uint8_t length() const { return header_.un.rfc4884.length; } /** * \brief Getter for the mtu field. * * \return Returns the mtu field value. */ uint16_t mtu() const { return Endian::be_to_host(header_.un.frag.mtu); } /** * \brief Getter for the original timestamp field. * * \return Returns the original timestamp value. */ uint32_t original_timestamp() const { return Endian::be_to_host(orig_timestamp_or_address_mask_); } /** * \brief Getter for the receive timestamp field. * * \return Returns the receive timestamp value. */ uint32_t receive_timestamp() const { return Endian::be_to_host(recv_timestamp_); } /** * \brief Getter for the transmit timestamp field. * * \return Returns the transmit timestamp value. */ uint32_t transmit_timestamp() const { return Endian::be_to_host(trans_timestamp_); } /** * \brief Getter for the address mask field. * * \return Returns the address mask value. */ address_type address_mask() const { return address_type(orig_timestamp_or_address_mask_); } /** * \brief Returns the header size. * * This method overrides PDU::header_size. This size includes the * payload and options size. * * \sa PDU::header_size */ uint32_t header_size() const; /** * \brief Returns the trailer size. * * This method overrides PDU::trailer_size. This size will hold the extensions size * * \sa PDU::header_size */ uint32_t trailer_size() const; /** * \brief Check whether 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(const uint8_t* ptr, uint32_t total_sz) const; /** * \brief Getter for the extensions field. * * \return The extensions field */ const ICMPExtensionsStructure& extensions() const { return extensions_; } /** * \brief Getter for the extensions field. * * \return The extensions field */ ICMPExtensionsStructure& extensions() { return extensions_; } /** * \brief Indicates whether this object contains ICMP extensions */ bool has_extensions() const { return !extensions_.extensions().empty(); } /** * \brief Sets whether the length field will be set for packets that use it * * As defined in RFC 4884, some ICMP packet types can have a length field. This * method controlers whether the length field is set or not. * * Note that this only indicates that the packet should use this field. The * actual value will be set during the packet's serialization. * * Note that, in order to br RFC compliant, if the size of the encapsulated * PDU is greater than 128, the length field will always be set, regardless * of whether this method was called or not. * * /param value true iff the length field should be set appropriately */ void use_length_field(bool value); /** * \brief Getter for the PDU's type. * * \sa PDU::pdu_type */ PDUType pdu_type() const { return pdu_flag; } /** * \sa PDU::clone */ ICMP* clone() const { return new ICMP(*this); } private: TINS_BEGIN_PACK struct icmp_header { uint8_t type; uint8_t code; uint16_t check; union { struct { uint16_t id; uint16_t sequence; } echo; uint32_t gateway; struct { uint16_t unused; uint16_t mtu; } frag; struct { uint8_t pointer; uint8_t length; uint16_t unused; } rfc4884; } un; } TINS_END_PACK; void checksum(uint16_t new_check); void write_serialization(uint8_t* buffer, uint32_t total_sz); uint32_t get_adjusted_inner_pdu_size() const; void try_parse_extensions(Memory::InputMemoryStream& stream); bool are_extensions_allowed() const; icmp_header header_; uint32_t orig_timestamp_or_address_mask_; uint32_t recv_timestamp_; uint32_t trans_timestamp_; ICMPExtensionsStructure extensions_; }; } // Tins #endif // TINS_ICMP_H