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pub mod icmp;
pub mod icmpv4_impl;
pub mod icmpv6_impl;
pub mod udp;
pub mod tcp;
use super::*;
use std::io;
///The possible headers on the transport layer
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum TransportHeader {
Udp(udp::UdpHeader),
Tcp(tcp::TcpHeader),
Icmpv4(Icmpv4Header),
Icmpv6(Icmpv6Header),
}
impl TransportHeader {
/// Returns Result::Some containing the udp header if self has the value Udp.
/// Otherwise None is returned.
pub fn udp(self) -> Option<udp::UdpHeader> {
use crate::TransportHeader::*;
if let Udp(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing the udp header if self has the value Udp.
/// Otherwise None is returned.
pub fn mut_udp(&mut self) -> Option<&mut udp::UdpHeader> {
use crate::TransportHeader::*;
if let Udp(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing the tcp header if self has the value Tcp.
/// Otherwise None is returned.
pub fn tcp(self) -> Option<tcp::TcpHeader> {
use crate::TransportHeader::*;
if let Tcp(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing a mutable refernce to the tcp header if self has the value Tcp.
/// Otherwise None is returned.
pub fn mut_tcp(&mut self) -> Option<&mut tcp::TcpHeader> {
use crate::TransportHeader::*;
if let Tcp(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing the ICMPv4 header if self has the value Icmpv4.
/// Otherwise None is returned.
pub fn icmpv4(self) -> Option<Icmpv4Header> {
use crate::TransportHeader::*;
if let Icmpv4(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing the ICMPv4 header if self has the value Icmpv4.
/// Otherwise None is returned.
pub fn mut_icmpv4(&mut self) -> Option<&mut Icmpv4Header> {
use crate::TransportHeader::*;
if let Icmpv4(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing the ICMPv6 header if self has the value Icmpv6.
/// Otherwise None is returned.
pub fn icmpv6(self) -> Option<Icmpv6Header> {
use crate::TransportHeader::*;
if let Icmpv6(value) = self {
Some(value)
} else {
None
}
}
/// Returns Result::Some containing the ICMPv6 header if self has the value Icmpv6.
/// Otherwise None is returned.
pub fn mut_icmpv6(&mut self) -> Option<&mut Icmpv6Header> {
use crate::TransportHeader::*;
if let Icmpv6(value) = self {
Some(value)
} else {
None
}
}
/// Returns the size of the transport header (in case of UDP fixed,
/// in case of TCP cotanining the options).
pub fn header_len(&self) -> usize {
use crate::TransportHeader::*;
match self {
Udp(_) => udp::UdpHeader::SERIALIZED_SIZE,
Tcp(value) => usize::from(value.header_len()),
Icmpv4(value) => value.header_len(),
Icmpv6(value) => value.header_len(),
}
}
/// Calculates the checksum for the transport header & sets it in the header for
/// an ipv4 header.
pub fn update_checksum_ipv4(&mut self, ip_header: &Ipv4Header, payload: &[u8]) -> Result<(), ValueError> {
use crate::TransportHeader::*;
match self {
Udp(header) => {
header.checksum = header.calc_checksum_ipv4(ip_header, payload)?;
},
Tcp(header) => {
header.checksum = header.calc_checksum_ipv4(ip_header, payload)?;
},
Icmpv4(header) => {
header.update_checksum(payload);
},
Icmpv6(_) => return Err(ValueError::Icmpv6InIpv4),
}
Ok(())
}
/// Calculates the checksum for the transport header & sets it in the header for
/// an ipv6 header.
pub fn update_checksum_ipv6(&mut self, ip_header: &Ipv6Header, payload: &[u8]) -> Result<(), ValueError> {
use crate::TransportHeader::*;
match self {
Icmpv4(header) => header.update_checksum(payload),
Icmpv6(header) => header.update_checksum(ip_header.source, ip_header.destination, payload)?,
Udp(header) => {
header.checksum = header.calc_checksum_ipv6(ip_header, payload)?;
},
Tcp(header) => {
header.checksum = header.calc_checksum_ipv6(ip_header, payload)?;
}
}
Ok(())
}
/// Write the transport header to the given writer.
pub fn write<T: io::Write + Sized>(&self, writer: &mut T) -> Result<(), WriteError> {
use crate::TransportHeader::*;
match self {
Icmpv4(value) => value.write(writer),
Icmpv6(value) => value.write(writer),
Udp(value) => value.write(writer),
Tcp(value) => value.write(writer).map_err(WriteError::from)
}
}
}