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use super::super::*;
extern crate byteorder;
use self::byteorder::{ByteOrder, BigEndian, ReadBytesExt, WriteBytesExt};
use std::io;
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum VlanHeader {
Single(SingleVlanHeader),
Double(DoubleVlanHeader)
}
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct SingleVlanHeader {
pub priority_code_point: u8,
pub drop_eligible_indicator: bool,
pub vlan_identifier: u16,
pub ether_type: u16,
}
impl SerializedSize for SingleVlanHeader {
const SERIALIZED_SIZE: usize = 4;
}
impl SingleVlanHeader {
pub fn read<T: io::Read + io::Seek + Sized >(reader: &mut T) -> Result<SingleVlanHeader, io::Error> {
let (priority_code_point, drop_eligible_indicator, vlan_identifier) = {
let mut buffer: [u8;2] = [0;2];
reader.read_exact(&mut buffer)?;
let drop_eligible_indicator = 0 != (buffer[0] & 0x10);
let priority_code_point = buffer[0] >> 5;
buffer[0] = buffer[0] & 0xf;
(priority_code_point, drop_eligible_indicator, BigEndian::read_u16(&buffer))
};
Ok(SingleVlanHeader{
priority_code_point: priority_code_point,
drop_eligible_indicator: drop_eligible_indicator,
vlan_identifier: vlan_identifier,
ether_type: reader.read_u16::<BigEndian>()?
})
}
pub fn write<T: io::Write + Sized>(&self, writer: &mut T) -> Result<(), WriteError> {
use ErrorField::*;
max_check_u8(self.priority_code_point, 0x7, VlanTagPriorityCodePoint)?;
max_check_u16(self.vlan_identifier, 0xfff, VlanTagVlanId)?;
{
let mut buffer: [u8;2] = [0;2];
BigEndian::write_u16(&mut buffer, self.vlan_identifier);
if self.drop_eligible_indicator {
buffer[0] = buffer[0] | 0x10;
}
buffer[0] = buffer[0] | (self.priority_code_point << 5);
writer.write_all(&buffer)?;
}
writer.write_u16::<BigEndian>(self.ether_type)?;
Ok(())
}
}
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct DoubleVlanHeader {
pub outer: SingleVlanHeader,
pub inner: SingleVlanHeader
}
impl SerializedSize for DoubleVlanHeader {
const SERIALIZED_SIZE: usize = 8;
}
impl DoubleVlanHeader {
pub fn read<T: io::Read + io::Seek + Sized >(reader: &mut T) -> Result<DoubleVlanHeader, ReadError> {
let outer = SingleVlanHeader::read(reader)?;
if (EtherType::VlanTaggedFrame as u16) != outer.ether_type {
use ReadError::*;
Err(VlanDoubleTaggingUnexpectedOuterTpid(outer.ether_type))
} else {
Ok(DoubleVlanHeader{
outer: outer,
inner: SingleVlanHeader::read(reader)?
})
}
}
pub fn write<T: io::Write + Sized>(&self, writer: &mut T) -> Result<(), WriteError> {
self.outer.write(writer)?;
self.inner.write(writer)
}
}
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct SingleVlanHeaderSlice<'a> {
slice: &'a [u8]
}
impl<'a> SingleVlanHeaderSlice<'a> {
pub fn from_slice(slice: &'a[u8]) -> Result<SingleVlanHeaderSlice<'a>, ReadError>{
use std::io::ErrorKind::UnexpectedEof;
use std::io::Error;
use ReadError::*;
if slice.len() < SingleVlanHeader::SERIALIZED_SIZE {
return Err(IoError(Error::from(UnexpectedEof)));
}
Ok(SingleVlanHeaderSlice::<'a> {
slice: &slice[..SingleVlanHeader::SERIALIZED_SIZE]
})
}
#[inline]
pub fn slice(&self) -> &'a [u8] {
self.slice
}
pub fn priority_code_point(&self) -> u8 {
self.slice[0] >> 5
}
pub fn drop_eligible_indicator(&self) -> bool {
0 != (self.slice[0] & 0x10)
}
pub fn vlan_identifier(&self) -> u16 {
let buffer = [self.slice[0] & 0xf, self.slice[1]];
BigEndian::read_u16(&buffer)
}
pub fn ether_type(&self) -> u16 {
BigEndian::read_u16(&self.slice[2..4])
}
pub fn to_header(&self) -> SingleVlanHeader {
SingleVlanHeader {
priority_code_point: self.priority_code_point(),
drop_eligible_indicator: self.drop_eligible_indicator(),
vlan_identifier: self.vlan_identifier(),
ether_type: self.ether_type(),
}
}
}
#[derive(Clone, Debug, Eq, PartialEq)]
pub struct DoubleVlanHeaderSlice<'a> {
slice: &'a [u8]
}
impl<'a> DoubleVlanHeaderSlice<'a> {
pub fn from_slice(slice: &'a[u8]) -> Result<DoubleVlanHeaderSlice<'a>, ReadError>{
use std::io::ErrorKind::UnexpectedEof;
use std::io::Error;
use ReadError::*;
if slice.len() < DoubleVlanHeader::SERIALIZED_SIZE {
return Err(IoError(Error::from(UnexpectedEof)));
}
Ok(DoubleVlanHeaderSlice {
slice: &slice[..DoubleVlanHeader::SERIALIZED_SIZE]
})
}
#[inline]
pub fn slice(&self) -> &'a [u8] {
self.slice
}
pub fn outer(&self) -> SingleVlanHeaderSlice<'a> {
SingleVlanHeaderSlice::<'a> {
slice: &self.slice[..SingleVlanHeader::SERIALIZED_SIZE]
}
}
pub fn inner(&self) -> SingleVlanHeaderSlice<'a> {
SingleVlanHeaderSlice::<'a> {
slice: &self.slice[SingleVlanHeader::SERIALIZED_SIZE..SingleVlanHeader::SERIALIZED_SIZE*2]
}
}
pub fn to_header(&self) -> DoubleVlanHeader {
DoubleVlanHeader {
outer: self.outer().to_header(),
inner: self.inner().to_header()
}
}
}