/*
* 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 <tins/macros.h>
#include <tins/pdu.h>
#include <tins/endianness.h>
#include <tins/ip_address.h>
#include <tins/icmp_extension.h>
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