udp_core.h

// Copyright 2021-2025 The Aerospace Corporation.
// This file is a part of SatCat5, licensed under CERN-OHL-W v2 or later.
// Type definitions for UDP datagrams and protocol handlers
 
#pragma once
 
#include <satcat5/ip_address.h>
#include <satcat5/net_core.h>
 
namespace satcat5 {
    namespace udp {
        // Alias for address and port types in the "udp" namespace.
        typedef satcat5::ip::Addr Addr;
        typedef satcat5::ip::Port Port;
 
        static constexpr unsigned HEADER_BYTES = 8;
 
        constexpr satcat5::udp::Port PORT_NONE          = {0};
        constexpr satcat5::udp::Port PORT_ECHO          = {7};
        constexpr satcat5::udp::Port PORT_DHCP_SERVER   = {67};
        constexpr satcat5::udp::Port PORT_DHCP_CLIENT   = {68};
        constexpr satcat5::udp::Port PORT_TFTP_SERVER   = {69};
        constexpr satcat5::udp::Port PORT_NTP_SERVER    = {123};
        constexpr satcat5::udp::Port PORT_PTP_EVENT     = {319};
        constexpr satcat5::udp::Port PORT_PTP_GENERAL   = {320};
        constexpr satcat5::udp::Port PORT_COAP          = {5683};
 
        constexpr satcat5::udp::Port PORT_CFGBUS_CMD    = {0x5A61};
        constexpr satcat5::udp::Port PORT_CFGBUS_ACK    = {0x5A62};
        constexpr satcat5::udp::Port PORT_CBOR_TLM      = {0x5A63};
        constexpr satcat5::udp::Port PORT_SWITCH_LOG    = {0x5A64};
 
        constexpr satcat5::ip::Addr MULTICAST_COAP(224, 0, 1, 187);
 
        struct Header {
            // UDP header fields.
            satcat5::udp::Port src;     
            satcat5::udp::Port dst;     
            u16 length;                 
 
            // Explicitly declare default constructor and assignment methods.
            Header() = default;
            Header(const Header& t) = default;
            Header& operator=(const Header& t) = default;
 
            void write_to(satcat5::io::Writeable* wr) const;
 
            bool read_from(satcat5::io::Readable* rd);
        };
 
        constexpr satcat5::udp::Header HEADER_EMPTY =
            {satcat5::udp::PORT_NONE, satcat5::udp::PORT_NONE, 0};
 
        class Address final : public satcat5::net::Address {
        public:
            explicit Address(satcat5::udp::Dispatch* iface);
            ~Address() {}
 
            void init(satcat5::udp::Dispatch* iface);
 
            void connect(
                const satcat5::udp::Addr& dstaddr,
                const satcat5::eth::MacAddr& dstmac,
                const satcat5::udp::Port& dstport,
                const satcat5::udp::Port& srcport = satcat5::udp::PORT_NONE,
                const satcat5::eth::VlanTag& vtag = satcat5::eth::VTAG_NONE);
 
            void connect(
                const satcat5::udp::Addr& dstaddr,
                const satcat5::udp::Port& dstport,
                const satcat5::udp::Port& srcport = satcat5::udp::PORT_NONE,
                const satcat5::eth::VlanTag& vtag = satcat5::eth::VTAG_NONE);
 
            // Required overrides from net::Address.
            void close() override {m_addr.close();}
            bool ready() const override {return m_addr.ready();}
            void retry() override {m_addr.retry();}
            satcat5::net::Dispatch* iface() const override;
            satcat5::io::Writeable* open_write(unsigned len) override;
            bool is_multicast() const override
                { return m_addr.is_multicast(); }
            bool matches_reply_address() const override;
            bool reply_is_multicast() const override
                { return m_addr.reply_is_multicast(); }
            void save_reply_address() override;
 
            // Various accessors.
            inline satcat5::ip::Addr dstaddr() const
                { return m_addr.dstaddr();}
            inline satcat5::eth::MacAddr dstmac() const
                { return m_addr.dstmac();}
            inline satcat5::udp::Port dstport() const
                { return m_dstport;}
            inline satcat5::eth::Dispatch* eth() const
                { return m_addr.eth(); }
            inline satcat5::eth::Header eth_header() const
                { return m_addr.eth_header(); }
            satcat5::ip::Header ip_header(unsigned len) const;
            inline satcat5::ip::Addr gateway() const
                { return m_addr.gateway(); }
            inline satcat5::eth::MacAddr srcmac() const
                { return m_addr.srcmac(); }
            inline satcat5::udp::Port srcport() const
                { return m_srcport; }
            inline satcat5::udp::Dispatch* udp() const
                { return m_iface; }
            inline satcat5::udp::Header udp_header(unsigned len) const
                { return {m_srcport, m_dstport, u16(len + 8)}; }
            inline satcat5::eth::VlanTag vtag() const
                { return m_addr.vtag(); }
 
        protected:
            satcat5::udp::Dispatch* m_iface;
            satcat5::ip::Address m_addr;
            satcat5::udp::Port m_dstport;
            satcat5::udp::Port m_srcport;
        };
 
        class AddressContainer {
        public:
            // Various accessors.
            inline satcat5::ip::Addr dstaddr() const
                { return m_addr.dstaddr(); }
            inline satcat5::eth::MacAddr dstmac() const
                { return m_addr.dstmac(); }
            inline satcat5::udp::Port dstport() const
                { return m_addr.dstport(); }
            inline satcat5::eth::Dispatch* eth() const
                { return m_addr.eth(); }
            satcat5::net::Dispatch* iface() const
                { return m_addr.iface(); }
            inline satcat5::ip::Addr gateway() const
                { return m_addr.gateway(); }
            inline satcat5::udp::Port srcport() const
                { return m_addr.srcport(); }
            inline satcat5::udp::Dispatch* udp() const
                { return m_addr.udp(); }
 
        protected:
            explicit AddressContainer(satcat5::udp::Dispatch* iface)
                : m_addr(iface) {}
            ~AddressContainer() {}
            satcat5::udp::Address m_addr;
        };
    }
}