2024-02-21 14:52:47 +03:00

533 lines
14 KiB
C++

/*
* 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_DHCP_H
#define TINS_DHCP_H
#include <vector>
#include <string>
#include <tins/bootp.h>
#include <tins/macros.h>
#include <tins/pdu_option.h>
#include <tins/cxxstd.h>
namespace Tins {
/**
* \class DHCP
* \brief Represents the DHCP PDU.
*
* This class represents a DHCP PDU. It contains helpers methods
* which make it easy to set/get specific option values.
*
* Note that when adding options, the "End" option is not added
* automatically, so you will have to add it yourself.
*
* Options can be retrieved easily from DHCP PDUs:
*
* \code
* // Sniff a packet from somewhere
* DHCP dhcp = get_dhcp_from_somewhere();
*
* // This retrieves the Domain Name Servers option and converts
* // it to a std::vector<IPv4Address>. Note that if this option
* // is not present, an option_not_found exception is thrown.
* for(const auto& address : dhcp.domain_name_servers()) {
* // address is an ip
* }
*
* \endcode
*/
class TINS_API DHCP : public BootP {
public:
/**
* This PDU's flag.
*/
static const PDU::PDUType pdu_flag = PDU::DHCP;
/**
* DHCP flags.
*/
enum Flags {
DISCOVER = 1,
OFFER = 2,
REQUEST = 3,
DECLINE = 4,
ACK = 5,
NAK = 6,
RELEASE = 7,
INFORM = 8
};
/**
* \brief DHCP options enum.
*/
enum OptionTypes {
PAD,
SUBNET_MASK,
TIME_OFFSET,
ROUTERS,
TIME_SERVERS,
NAME_SERVERS,
DOMAIN_NAME_SERVERS,
LOG_SERVERS,
COOKIE_SERVERS,
LPR_SERVERS,
IMPRESS_SERVERS,
RESOURCE_LOCATION_SERVERS,
HOST_NAME,
BOOT_SIZE,
MERIT_DUMP,
DOMAIN_NAME,
SWAP_SERVER,
ROOT_PATH,
EXTENSIONS_PATH,
IP_FORWARDING,
NON_LOCAL_SOURCE_ROUTING,
POLICY_FILTER,
MAX_DGRAM_REASSEMBLY,
DEFAULT_IP_TTL,
PATH_MTU_AGING_TIMEOUT,
PATH_MTU_PLATEAU_TABLE,
INTERFACE_MTU,
ALL_SUBNETS_LOCAL,
BROADCAST_ADDRESS,
PERFORM_MASK_DISCOVERY,
MASK_SUPPLIER,
ROUTER_DISCOVERY,
ROUTER_SOLICITATION_ADDRESS,
STATIC_ROUTES,
TRAILER_ENCAPSULATION,
ARP_CACHE_TIMEOUT,
IEEE802_3_ENCAPSULATION,
DEFAULT_TCP_TTL,
TCP_KEEPALIVE_INTERVAL,
TCP_KEEPALIVE_GARBAGE,
NIS_DOMAIN,
NIS_SERVERS,
NTP_SERVERS,
VENDOR_ENCAPSULATED_OPTIONS,
NETBIOS_NAME_SERVERS,
NETBIOS_DD_SERVER,
NETBIOS_NODE_TYPE,
NETBIOS_SCOPE,
FONT_SERVERS,
X_DISPLAY_MANAGER,
DHCP_REQUESTED_ADDRESS,
DHCP_LEASE_TIME,
DHCP_OPTION_OVERLOAD,
DHCP_MESSAGE_TYPE,
DHCP_SERVER_IDENTIFIER,
DHCP_PARAMETER_REQUEST_LIST,
DHCP_MESSAGE,
DHCP_MAX_MESSAGE_SIZE,
DHCP_RENEWAL_TIME,
DHCP_REBINDING_TIME,
VENDOR_CLASS_IDENTIFIER,
DHCP_CLIENT_IDENTIFIER,
NWIP_DOMAIN_NAME,
NWIP_SUBOPTIONS,
USER_CLASS = 77,
FQDN = 81,
DHCP_AGENT_OPTIONS = 82,
SUBNET_SELECTION = 118,
AUTHENTICATE = 210,
END = 255
};
/**
* The DHCP option type.
*/
typedef PDUOption<uint8_t, DHCP> option;
/**
* The type used to store the DHCP options.
*/
typedef std::vector<option> options_type;
/**
* \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 DHCP.
*
* This sets the hwtype and hlen fields to match the ethernet
* type and length.
*/
DHCP();
/**
* \brief Constructs a DHCP object from a buffer.
*
* If there is not enough size for a BootP header, or any of
* the TLV options contains an invalid size field, then a
* malformed_packet exception is thrown.
*
* \param buffer The buffer from which this PDU will be constructed.
* \param total_sz The total size of the buffer.
*/
DHCP(const uint8_t* buffer, uint32_t total_sz);
/**
* \brief Adds a new option to this DHCP PDU.
* \param opt The option to be added.
*/
void add_option(const option& opt);
#if TINS_IS_CXX11
/**
* \brief Adds a new option to this DHCP PDU.
*
* The option is move-constructed.
*
* \param opt The option to be added.
*/
void add_option(option &&opt) {
internal_add_option(opt);
options_.push_back(std::move(opt));
}
#endif
/**
* \brief Removes a DHCP option.
*
* If there are multiple options of the given type, only the first one
* will be removed.
*
* \param type The type of the option to be removed.
* \return true if the option was removed, false otherwise.
*/
bool remove_option(OptionTypes type);
/**
* \brief Searchs for an option that matchs the given flag.
* \param opt_flag The flag to be searched.
* \return A pointer to the option, or 0 if it was not found.
*/
const option* search_option(OptionTypes opt) const;
/**
* \brief Adds a type option to the option list.
*
* The new option is appended at the end of the list.
*
* \param type The type of this DHCP PDU.
*/
void type(Flags type);
/**
* \brief Adds an end option to the option list.
*
* The new option is appended at the end of the list.
*
* The END option is not added automatically. You should explicitly
* add it at the end of the DHCP options for the PDU to be
* standard-compliant.
*/
void end();
/**
* \brief Adds a server identifier option.
*
* The new option is appended at the end of the list.
*
* \param ip The server's IP address.
*/
void server_identifier(ipaddress_type ip);
/**
* \brief Adds an IP address lease time option.
*
* The new option is appended at the end of the list.
*
* \param time The lease time.
*/
void lease_time(uint32_t time);
/**
* \brief Adds a lease renewal time option.
*
* The new option is appended at the end of the list.
*
* \param time The lease renew time.
*/
void renewal_time(uint32_t time);
/**
* \brief Adds a rebind time option.
*
* The new option is appended at the end of the list.
*
* \param time The lease rebind time.
*/
void rebind_time(uint32_t time);
/**
* \brief Adds a subnet mask option.
*
* The new option is appended at the end of the list.
*
* \param mask The subnet mask.
*/
void subnet_mask(ipaddress_type mask);
/**
* \brief Adds a routers option.
*
* The new option is appended at the end of the list.
*
* \param routers A list of ip addresses.
*/
void routers(const std::vector<ipaddress_type>& routers);
/**
* \brief Adds a domain name servers option.
*
* The new option is appended at the end of the list.
*
* \param dns A list of ip addresses.
*/
void domain_name_servers(const std::vector<ipaddress_type>& dns);
/**
* \brief Adds a broadcast address option.
*
* The new option is appended at the end of the list.
*
* \param addr The broadcast address.
*/
void broadcast(ipaddress_type addr);
/**
* \brief Adds a requested address option.
*
* The new option is appended at the end of the list.
*
* \param addr The requested address.
*/
void requested_ip(ipaddress_type addr);
/**
* \brief Adds a domain name option.
*
* The new option is appended at the end of the list.
*
* \param name The domain name.
*/
void domain_name(const std::string& name);
/**
* \brief Adds a hostname option.
*
* The new option is appended at the end of the list.
*
* \param name The hostname.
*/
void hostname(const std::string& name);
// Option getters
/**
* \brief Searchs for a type option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return uint8_t containing the type option.
*/
uint8_t type() const;
/**
* \brief Searchs for a server identifier option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return ipaddress_type Containing the server identifier.
*/
ipaddress_type server_identifier() const;
/**
* \brief Searchs for a lease time option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return uint32_t Containing the lease time.
*/
uint32_t lease_time() const;
/**
* \brief Searchs for a lease renewal time option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return uint32_t Containing the renewal time.
*/
uint32_t renewal_time() const;
/**
* \brief Searchs for a rebind time option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return uint32_t Containing the rebind time.
*/
uint32_t rebind_time() const;
/**
* \brief Searchs for a subnet mask option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return ipaddress_type Containing the subnet mask.
*/
ipaddress_type subnet_mask() const;
/**
* \brief Searchs for a routers option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return std::vector<ipaddress_type> Containing the routers
* option data.
*/
std::vector<ipaddress_type> routers() const;
/**
* \brief Searchs for a dns option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return The list of DNS servers provided.
*/
std::vector<ipaddress_type> domain_name_servers() const;
/**
* \brief Searchs for a broadcast option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return ipaddress_type Containing the broadcast address.
*/
ipaddress_type broadcast() const;
/**
* \brief Searchs for a requested option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return ipaddress_type Containing the requested IP address.
*/
ipaddress_type requested_ip() const;
/**
* \brief Searchs for a domain name option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return std::string Containing the domain name.
*/
std::string domain_name() const;
/**
* \brief Searchs for a hostname option.
*
* If the option is not found, an option_not_found exception
* is thrown.
*
* \return std::string Containing the hostname.
*/
std::string hostname() const;
/**
* \brief Getter for the options list.
* \return The option list.
*/
const options_type options() const { return options_; }
/**
* \brief Getter for the PDU's type.
* \sa PDU::pdu_type
*/
PDUType pdu_type() const { return pdu_flag; }
/**
* \brief Getter for the header size.
* \return Returns the BOOTP header size.
* \sa PDU::header_size
*/
uint32_t header_size() const;
/**
* \sa PDU::clone
*/
DHCP* clone() const {
return new DHCP(*this);
}
private:
static const uint32_t MAX_DHCP_SIZE;
void write_serialization(uint8_t* buffer, uint32_t total_sz);
template <typename T>
T search_and_convert(OptionTypes opt) const {
const option* option = search_option(opt);
if (!option) {
throw option_not_found();
}
return option->to<T>();
}
void internal_add_option(const option& opt);
serialization_type serialize_list(const std::vector<ipaddress_type>& ip_list);
options_type::const_iterator search_option_iterator(OptionTypes opt) const;
options_type::iterator search_option_iterator(OptionTypes opt);
options_type options_;
uint32_t size_;
};
} // Tins
#endif // TINS_DHCP_H