/* * \brief Internet protocol version 4. * \author Stefan Kalkowski * \date 2010-08-19 */ /* * Copyright (C) 2010-2017 Genode Labs GmbH * * This file is part of the Genode OS framework, which is distributed * under the terms of the GNU Affero General Public License version 3. */ #ifndef _IPV4_H_ #define _IPV4_H_ /* Genode */ #include #include #include #include #include #include namespace Genode { class Output; } namespace Net { enum { IPV4_ADDR_LEN = 4 }; class Ipv4_address; class Ipv4_packet; } struct Net::Ipv4_address : Network_address { Ipv4_address(Genode::uint8_t value = 0) : Network_address(value) { } Ipv4_address(void *src) : Network_address(src) { } bool valid() const { return *this != Ipv4_address(); } Genode::uint32_t to_uint32_big_endian() const; static Ipv4_address from_uint32_big_endian(Genode::uint32_t ip_raw); Genode::uint32_t to_uint32_little_endian() const; static Ipv4_address from_uint32_little_endian(Genode::uint32_t ip_raw); bool is_in_range(Ipv4_address const &first, Ipv4_address const &last) const; } __attribute__((packed)); /** * Data layout of this class conforms to an IPv4 packet (RFC 791) * * IPv4-header-format: * * ---------------------------------------------------------------- * | 0-3 | 4-7 | 8-11 | 12-15 | 16-18 | 19-23 | 24-27 | 28-31 | * ---------------------------------------------------------------- * | version | IHL | service-type | total-length | * ---------------------------------------------------------------- * | identifikation | flags | fragment-offset | * ---------------------------------------------------------------- * | ttl | protocol | header-checksum | * ---------------------------------------------------------------- * | source-ip-address | * ---------------------------------------------------------------- * | destination-ip-address | * ---------------------------------------------------------------- * | options ... | * ---------------------------------------------------------------- */ class Net::Ipv4_packet { public: enum Size { ADDR_LEN = IPV4_ADDR_LEN, /* Ip address length in bytes */ }; static Ipv4_address current() { return Ipv4_address((Genode::uint8_t)0x00); } static Ipv4_address broadcast() { return Ipv4_address((Genode::uint8_t)0xff); } static Ipv4_address ip_from_string(const char *ip); void update_checksum(); bool checksum_error() const; private: /************************ ** IPv4 header fields ** ************************/ unsigned _header_length : 4; unsigned _version : 4; unsigned _diff_service : 6; unsigned _ecn : 2; Genode::uint16_t _total_length; Genode::uint16_t _identification; unsigned _flags : 3; unsigned _fragment_offset : 13; Genode::uint8_t _time_to_live; Genode::uint8_t _protocol; Genode::uint16_t _checksum; Genode::uint8_t _src[ADDR_LEN]; Genode::uint8_t _dst[ADDR_LEN]; unsigned _data[0]; public: enum class Protocol : Genode::uint8_t { ICMP = 1, TCP = 6, UDP = 17, }; struct Bad_data_type : Genode::Exception { }; template T const &data(Genode::size_t data_size) const { if (data_size < sizeof(T)) { throw Bad_data_type(); } return *(T const *)(_data); } template T &data(Genode::size_t data_size) { if (data_size < sizeof(T)) { throw Bad_data_type(); } return *(T *)(_data); } template T &construct_at_data(SIZE_GUARD &size_guard) { size_guard.add(sizeof(T)); return *Genode::construct_at(_data); } Genode::size_t size(Genode::size_t max_size) const; /*************** ** Accessors ** ***************/ Genode::size_t header_length() const { return _header_length; } Genode::uint8_t version() const { return _version; } Genode::uint8_t diff_service() const { return _diff_service; } Genode::uint8_t ecn() const { return _ecn; } Genode::size_t total_length() const { return host_to_big_endian(_total_length); } Genode::uint16_t identification() const { return host_to_big_endian(_identification); } Genode::uint8_t flags() const { return _flags; } Genode::size_t fragment_offset() const { return _fragment_offset; } Genode::uint8_t time_to_live() const { return _time_to_live; } Protocol protocol() const { return (Protocol)_protocol; } Genode::uint16_t checksum() const { return host_to_big_endian(_checksum); } Ipv4_address src() const { return Ipv4_address((void *)&_src); } Ipv4_address dst() const { return Ipv4_address((void *)&_dst); } void header_length(Genode::size_t v) { _header_length = v; } void version(Genode::uint8_t v) { _version = v; } void diff_service(Genode::uint8_t v) { _diff_service = v; ; } void ecn(Genode::uint8_t v) { _ecn = v; ; } void total_length(Genode::size_t v) { _total_length = host_to_big_endian((Genode::uint16_t)v); } void identification(Genode::uint16_t v) { _identification = host_to_big_endian(v); } void flags(Genode::uint8_t v) { _flags = v; ; } void fragment_offset(Genode::size_t v) { _fragment_offset = v; ; } void time_to_live(Genode::uint8_t v) { _time_to_live = v; } void protocol(Protocol v) { _protocol = (Genode::uint8_t)v; } void checksum(Genode::uint16_t checksum) { _checksum = host_to_big_endian(checksum); } void src(Ipv4_address v) { v.copy(&_src); } void dst(Ipv4_address v) { v.copy(&_dst); } /********* ** log ** *********/ void print(Genode::Output &output) const; } __attribute__((packed)); namespace Genode { inline size_t ascii_to(char const *s, Net::Ipv4_address &result); } Genode::size_t Genode::ascii_to(char const *s, Net::Ipv4_address &result) { Net::Ipv4_address buf; size_t number_idx = 0; size_t read_len = 0; while (1) { /* read the current number, fail if there's no number */ size_t number_len = ascii_to_unsigned(s, buf.addr[number_idx], 10); if (!number_len) { return 0; } /* update read length and number index */ read_len += number_len; number_idx++; /* if we have all numbers, fill result and return read length */ if (number_idx == sizeof(buf.addr) / sizeof(buf.addr[0])) { result = buf; return read_len; } /* as it was not the last number, check for the following dot */ s += number_len; if (*s != '.') { return 0; } read_len++; s++; } } #endif /* _IPV4_H_ */