IPv4 level socket option setter/getter helper. More...

#include <IPOptions.hxx>

Inheritance diagram for cosmos::IP4Options:

Public Types
enum class	ToS : uint8_t { LOWDELAY = IPTOS_LOWDELAY , THROUGHPUT = IPTOS_THROUGHPUT , RELIABILITY = IPTOS_RELIABILITY , MINCOST = IPTOS_MINCOST }
	IP type-of-service field values as used in setTypeOfService(). More...

Public Types inherited from cosmos::IPOptBase< OptLevel::IP >
enum	MTUDiscoveryMode
	Discovery mode settings used in setMTUDiscoveryMode(). More...

Public Member Functions
void	setBindAddressNoPort (const bool on_off)
	Don't reserve an ephemeral source port at bind() time if the port is set to 0.

void	setFreeBind (const bool on_off)
	Allow to bind() to a non-local or not yet existing address.

void	setHeaderIncluded (const bool on_off)
	Let userspace supply an IP header in front of the user data when sending.

void	setLocalPortRange (const uint16_t lower_bound, const uint16_t upper_bound)
	Sets the range of ports on which automatic source port selection is based.

void	resetLocalPortRange ()

std::pair< uint16_t, uint16_t >	getLocalPortRange () const
	Gets the currently set range of ports for automatic source port selection.

int	getMTU () const
	Returns the currently known path MTU for the socket.

MTUDiscoveryMode	getMTUDiscoveryMode () const
	Gets the current MTU discovery mode setting for the socket.

void	setMTUDiscoveryMode (const MTUDiscoveryMode mode)
	Sets a new MTU discovery mode setting.

void	setNoDefrag (const bool on_off)
	Disable reassembly of outgoing packets in the netfilter layer.

void	setPassSecurity (const bool on_off)
	Enable receiving of labeled IPSEC or NetLabel security context in `revmsg()`.

void	setPacketInfo (const bool on_off)
	Enable receiving of IP_PKTINFO ancillary messages in `revmsg()`.

void	setReceiveErrors (const bool on_off)
	Enable extended reliable error reporting for datagram sockets.

void	setReceiveOptions (const bool on_off)
	Enable reception of incoming IP options in IP_OPTIONS control messages.

void	setReceiveRawOptions (const bool on_off)
	Enable reception of raw incoming IP options.

void	setReceiveOrigDestAddr (const bool on_off)
	Enable reception of the IP_ORIGDSTADDR ancillary message in `recvmsg()`.

void	setReceiveTOS (const bool on_off)
	Enable reception of the IP_TOS ancillary message in `recvmsg()`.

void	setReceiveTTL (const bool on_off)
	Enable reception of IP_TTL control messages in `recvmsg()`.

void	setRouterAlert (const bool on_off)
	Pass to-be-forwarded packets with the IP router alert option set to this socket.

void	setTypeOfService (const ToS tos)
	Sets the type-of-service field that is sent with every IP packet.

ToS	getTypeOfService () const
	Gets the current type-of-service field that is sent with every IP packet.

void	setTransparentProxying (const bool on_off)
	Enable transparent proxying on this socket.

void	setTimeToLive (const int ttl)
	Sets the time-to-live field that is used in every packet sent from this socket.

int	getTimeToLive () const
	Returns the current time-to-live field setting for this socket.

std::string	getPeerSec () const
	Returns the labeled IPSEC or NetLabel of the peer.

Friends
class	IPSocketT< SocketFamily::INET >

Additional Inherited Members
Protected Member Functions inherited from cosmos::SockOptBase< LEVEL >
	SockOptBase (FileDescriptor fd)
	Perform socket options on the given file descriptor.

bool	getBoolOption (const OptName name) const
	Return a boolean style option.

void	setBoolOption (const OptName name, const bool val)
	Set a boolean style option.

int	getIntOption (const OptName name) const
	Return an integer option.

void	setIntOption (const OptName name, const int val)
	Set an integer option.

std::string	getStringOption (const OptName name, size_t max_len) const
	Return a null terminated string option.

void	setStringOption (const OptName name, const SysString str)
	Set a null terminated string option.

std::string	getPeerSec () const
	Returns the labeled IPSEC or NetLabel of the peer.

	SockOptBase (const SockOptBase &)=delete

SockOptBase &	operator= (const SockOptBase &)=delete

Protected Attributes inherited from cosmos::SockOptBase< LEVEL >
FileDescriptor	m_sock
	The socket file descriptor to operate on.

Static Protected Attributes inherited from cosmos::SockOptBase< LEVEL >
static constexpr OptLevel	M_LEVEL = LEVEL
	The option level to operate on.

Detailed Description

IPv4 level socket option setter/getter helper.

This helper type offers IPv4 level options that are shared between all IPv4 protocol based sockets.

This type cannot be freely created, but can only be obtained via e.g. UDP4Socket::ipOptions().

Definition at line 57 of file IPOptions.hxx.

Member Enumeration Documentation

◆ ToS

enum class cosmos::IP4Options::ToS : uint8_t

strong

IP type-of-service field values as used in setTypeOfService().

Enumerator
LOWDELAY	minimize delay for interactive traffic.
THROUGHPUT	Optimize for throughput.
RELIABILITY	Optimize for reliability.
MINCOST	used for "filler data" where slow transmission doesn't matter.

Definition at line 63 of file IPOptions.hxx.

                       : uint8_t {
                LOWDELAY    = IPTOS_LOWDELAY,
                THROUGHPUT  = IPTOS_THROUGHPUT,
                RELIABILITY = IPTOS_RELIABILITY,
                MINCOST     = IPTOS_MINCOST
        };

Member Function Documentation

◆ getLocalPortRange()

std::pair< uint16_t, uint16_t > cosmos::IP4Options::getLocalPortRange ( ) const

Gets the currently set range of ports for automatic source port selection.

See also: setLocalPortRange()

Returns: a pair consisting of the upper bound (as first) and the lower bound (second).

Definition at line 18 of file IPOptions.cxx.

                                                                {
        const auto bounds = getsockopt<uint32_t>(m_sock, M_LEVEL, OptName{IP_LOCAL_PORT_RANGE});
 
        const uint16_t lower_bound = static_cast<uint16_t>(bounds);
        const uint16_t upper_bound = static_cast<uint16_t>(bounds >> 16);
 
        return std::make_pair(upper_bound, lower_bound);
}

◆ getMTU()

int cosmos::IP4Options::getMTU ( ) const

inline

Returns the currently known path MTU for the socket.

This is only possible for getting and if the socket has been connect()'ed.

Definition at line 128 of file IPOptions.hxx.

                           {
                return getIntOption(OptName{IP_MTU});
        }

◆ getMTUDiscoveryMode()

MTUDiscoveryMode cosmos::IP4Options::getMTUDiscoveryMode ( ) const

inline

Gets the current MTU discovery mode setting for the socket.

Definition at line 133 of file IPOptions.hxx.

                                                     {
                const auto int_mode = getIntOption(OptName{IP_MTU_DISCOVER});
                return MTUDiscoveryMode{int_mode};
        }

◆ getPeerSec()

std::string cosmos::SockOptBase< LEVEL >::getPeerSec ( ) const

Returns the labeled IPSEC or NetLabel of the peer.

This only works if IPSEC or NetLabel is configured on both the sending and receiving hosts. This option is supported for TCP and SCTP sockets on IP level or for UNIX domain sockets.

The returned string will have the proper length and null termination. The encoding of the returned string is unspecified though. In particular it is not guaranteed to be ASCII or UTF-8.

Definition at line 50 of file SockOptBase.cxx.

                                               {
        std::string ret;
        ret.resize(cosmos::max::NAME);
 
        socklen_t length;
 
        while (true) {
                try {
                        length = getsockopt(m_sock, M_LEVEL, OptName{SO_PEERSEC}, ret.data(), ret.size());
 
                        if (ret[length-1] == '\0')
                                // it is not guaranteed that the string is
                                // null terminated, thus check this
                                length--;
 
                        ret.resize(length);
                        return ret;
                } catch (const RangeError &ex) {
                        if (!ex.requiredLengthKnown() || ex.requiredLength() < ret.size()) {
                                throw;
                        }
 
                        // retry with larger size
                        ret.resize(ret.size());
                }
        }
}

◆ getTimeToLive()

int cosmos::IP4Options::getTimeToLive ( ) const

inline

Returns the current time-to-live field setting for this socket.

Definition at line 257 of file IPOptions.hxx.

                                  {
                return getIntOption(OptName{IP_TTL});
        }

◆ getTypeOfService()

IP4Options::ToS cosmos::IP4Options::getTypeOfService ( ) const

Gets the current type-of-service field that is sent with every IP packet.

Definition at line 31 of file IPOptions.cxx.

                                                 {
        const auto tos = getsockopt<uint8_t>(m_sock, M_LEVEL, OptName{IP_TOS});
        return ToS{tos};
}

◆ resetLocalPortRange()

void cosmos::IP4Options::resetLocalPortRange ( )

inline

Definition at line 110 of file IPOptions.hxx.

                                   {
                setLocalPortRange(0, 0);
        }

◆ setBindAddressNoPort()

void cosmos::IP4Options::setBindAddressNoPort ( const bool on_off )

inline

Don't reserve an ephemeral source port at bind() time if the port is set to 0.

Instead the port will be automatically chosen during connect() time. This allows source port sharing as long as the 4-tuple of source and sender address is unique.

Definition at line 82 of file IPOptions.hxx.

                                                     {
                setBoolOption(OptName{IP_BIND_ADDRESS_NO_PORT}, on_off);
        }

◆ setFreeBind()

void cosmos::IP4Options::setFreeBind ( const bool on_off )

inline

Allow to bind() to a non-local or not yet existing address.

Definition at line 87 of file IPOptions.hxx.

                                            {
                setBoolOption(OptName{IP_FREEBIND}, on_off);
        }

◆ setHeaderIncluded()

void cosmos::IP4Options::setHeaderIncluded ( const bool on_off )

inline

Let userspace supply an IP header in front of the user data when sending.

This is only allowed for SocketType::RAW. When used then other options like setReceiveOptions(), setReceiveTTL() and setReceiveTOS() will have no effect.

Definition at line 97 of file IPOptions.hxx.

                                                  {
                setBoolOption(OptName{IP_HDRINCL}, on_off);
        }

◆ setLocalPortRange()

void cosmos::IP4Options::setLocalPortRange	(	const uint16_t	lower_bound,
		const uint16_t	upper_bound )

Sets the range of ports on which automatic source port selection is based.

This cannot be outside the range of the global proc ip_local_port_range setting. The lower bound has to be less than the upper_bound. If both are set to zero then the setting is reset to the default.

Definition at line 11 of file IPOptions.cxx.

                                                                                         {
        // the upper 16 bits are the upper_bound, the lower 16 bits the lower bound.
        const uint32_t setting = (static_cast<uint32_t>(upper_bound) << 16) |
                static_cast<uint32_t>(lower_bound);
        setsockopt(m_sock, M_LEVEL, OptName{IP_LOCAL_PORT_RANGE}, setting);
}

◆ setMTUDiscoveryMode()

void cosmos::IP4Options::setMTUDiscoveryMode ( const MTUDiscoveryMode mode )

inline

Sets a new MTU discovery mode setting.

Definition at line 139 of file IPOptions.hxx.

                                                              {
                setIntOption(OptName{IP_MTU_DISCOVER}, to_integral(mode));
        }

◆ setNoDefrag()

void cosmos::IP4Options::setNoDefrag ( const bool on_off )

inline

Disable reassembly of outgoing packets in the netfilter layer.

This is only supported for SocketType::RAW sockets.

Definition at line 147 of file IPOptions.hxx.

                                            {
                setBoolOption(OptName{IP_NODEFRAG}, on_off);
        }

◆ setPacketInfo()

void cosmos::IP4Options::setPacketInfo ( const bool on_off )

inline

Enable receiving of IP_PKTINFO ancillary messages in revmsg().

Definition at line 157 of file IPOptions.hxx.

                                              {
                setBoolOption(OptName{IP_PKTINFO}, on_off);
        }

◆ setPassSecurity()

void cosmos::IP4Options::setPassSecurity ( const bool on_off )

inline

Enable receiving of labeled IPSEC or NetLabel security context in revmsg().

Definition at line 152 of file IPOptions.hxx.

                                                {
                setBoolOption(OptName{IP_PASSSEC}, on_off);
        }

◆ setReceiveErrors()

void cosmos::IP4Options::setReceiveErrors ( const bool on_off )

inline

Enable extended reliable error reporting for datagram sockets.

If enabled then SocketError ancillary messages can be received via Socket::receiveMessage() with MessageFlag::ERRQUEUE set.

Definition at line 167 of file IPOptions.hxx.

                                                 {
                setBoolOption(OptName{IP_RECVERR}, on_off);
        }

◆ setReceiveOptions()

void cosmos::IP4Options::setReceiveOptions ( const bool on_off )

inline

Enable reception of incoming IP options in IP_OPTIONS control messages.

This is not supported for SocketType::STREAM sockets.

Definition at line 175 of file IPOptions.hxx.

                                                  {
                setBoolOption(OptName{IP_RECVOPTS}, on_off);
        }

◆ setReceiveOrigDestAddr()

void cosmos::IP4Options::setReceiveOrigDestAddr ( const bool on_off )

inline

Enable reception of the IP_ORIGDSTADDR ancillary message in recvmsg().

The ancillary message contains the original destination address of the datagram being received as a struct sockaddr_in. This is used together with setTransparentProxying(), to get the original destination address for use with UDP sockets.

Definition at line 196 of file IPOptions.hxx.

                                                       {
                setBoolOption(OptName{IP_RECVORIGDSTADDR}, on_off);
        }

◆ setReceiveRawOptions()

void cosmos::IP4Options::setReceiveRawOptions ( const bool on_off )

inline

Enable reception of raw incoming IP options.

This is similar to setReceiveOptions() but returns raw unprocessed options with timestamp and route record options not filled in for this hop.

Definition at line 185 of file IPOptions.hxx.

                                                     {
                setBoolOption(OptName{IP_RETOPTS}, on_off);
        }

◆ setReceiveTOS()

void cosmos::IP4Options::setReceiveTOS ( const bool on_off )

inline

Enable reception of the IP_TOS ancillary message in recvmsg().

The ancillary message contains a byte which specifies the type of service / precedence field of the packet header.

Definition at line 205 of file IPOptions.hxx.

                                              {
                setBoolOption(OptName{IP_RECVTOS}, on_off);
        }

◆ setReceiveTTL()

void cosmos::IP4Options::setReceiveTTL ( const bool on_off )

inline

Enable reception of IP_TTL control messages in recvmsg().

The control message contains a 32-bit integer field containing the time-to-live field of the received packet. This is not supported for SocketType::STREAM sockets.

Definition at line 215 of file IPOptions.hxx.

                                              {
                setBoolOption(OptName{IP_RECVTTL}, on_off);
        }

◆ setRouterAlert()

void cosmos::IP4Options::setRouterAlert ( const bool on_off )

inline

Pass to-be-forwarded packets with the IP router alert option set to this socket.

This is only valid for SocketType::RAW sockets. It's the user's responsibility to send these messages out again, the kernel won't forward them with this option enabled.

Definition at line 225 of file IPOptions.hxx.

                                               {
                setBoolOption(OptName{IP_ROUTER_ALERT}, on_off);
        }

◆ setTimeToLive()

void cosmos::IP4Options::setTimeToLive ( const int ttl )

inline

Sets the time-to-live field that is used in every packet sent from this socket.

Definition at line 252 of file IPOptions.hxx.

                                          {
                setIntOption(OptName{IP_TTL}, ttl);
        }

◆ setTransparentProxying()

void cosmos::IP4Options::setTransparentProxying ( const bool on_off )

inline

Enable transparent proxying on this socket.

Transparent proxying allows a range of IP addresses to be considered "local" although they aren't. A userspace process can then intercept these non-local packets and apply proxying to them. Setting this socket option requires CAP_NET_ADMIN capabilities.

To get this fully working, iptables has also to be added to the mix. See this nice write-up:

https://powerdns.org/tproxydoc/tproxy.md.html

Definition at line 247 of file IPOptions.hxx.

                                                       {
                setBoolOption(OptName{IP_TRANSPARENT}, on_off);
        }

◆ setTypeOfService()

void cosmos::IP4Options::setTypeOfService ( const ToS tos )

Sets the type-of-service field that is sent with every IP packet.

Definition at line 27 of file IPOptions.cxx.

                                               {
        setsockopt(m_sock, M_LEVEL, OptName{IP_TOS}, to_integral(tos));
}

Friends And Related Symbol Documentation

◆ IPSocketT< SocketFamily::INET >

friend class IPSocketT< SocketFamily::INET >

friend

Definition at line 276 of file IPOptions.hxx.

The documentation for this class was generated from the following files:

include/net/IPOptions.hxx
src/net/IPOptions.cxx

Public Types

Public Member Functions

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ ToS

Member Function Documentation

◆ getLocalPortRange()

◆ getMTU()

◆ getMTUDiscoveryMode()

◆ getPeerSec()

◆ getTimeToLive()

◆ getTypeOfService()

◆ resetLocalPortRange()

◆ setBindAddressNoPort()

◆ setFreeBind()

◆ setHeaderIncluded()

◆ setLocalPortRange()

◆ setMTUDiscoveryMode()

◆ setNoDefrag()

◆ setPacketInfo()

◆ setPassSecurity()

◆ setReceiveErrors()

◆ setReceiveOptions()

◆ setReceiveOrigDestAddr()

◆ setReceiveRawOptions()

◆ setReceiveTOS()

◆ setReceiveTTL()

◆ setRouterAlert()

◆ setTimeToLive()

◆ setTransparentProxying()

◆ setTypeOfService()

Friends And Related Symbol Documentation

◆ IPSocketT< SocketFamily::INET >