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#![allow(clippy::cast_lossless)]
use crate::pcapng::blocks::common::opts_from_slice;
use crate::errors::PcapError;
use crate::DataLink;
use byteorder::{ByteOrder, ReadBytesExt};
use crate::pcapng::{CustomUtf8Option, CustomBinaryOption, UnknownOption};
use std::borrow::Cow;
use derive_into_owned::IntoOwned;
/// An Interface Description Block (IDB) is the container for information describing an interface
/// on which packet data is captured.
#[derive(Clone, Debug, IntoOwned)]
pub struct InterfaceDescriptionBlock<'a> {
/// A value that defines the link layer type of this interface.
/// The list of Standardized Link Layer Type codes is available in the
/// [tcpdump.org link-layer header types registry.](http://www.tcpdump.org/linktypes.html).
pub linktype: DataLink,
/// Not used - MUST be filled with 0 by pcap file writers, and MUST be ignored by pcapng file readers.
pub reserved: u16,
/// Maximum number of octets captured from each packet.
/// The portion of each packet that exceeds this value will not be stored in the file.
/// A value of zero indicates no limit.
pub snaplen: u32,
/// Options
pub options: Vec<InterfaceDescriptionOption<'a>>
}
impl<'a> InterfaceDescriptionBlock<'a> {
pub fn from_slice<B:ByteOrder>(mut slice: &'a [u8]) -> Result<(&'a [u8], Self), PcapError> {
if slice.len() < 8 {
return Err(PcapError::InvalidField("InterfaceDescriptionBlock: block length < 8"));
}
let linktype = (slice.read_u16::<B>()? as u32).into();
let reserved = slice.read_u16::<B>()?;
let snaplen = slice.read_u32::<B>()?;
let (slice, options) = InterfaceDescriptionOption::from_slice::<B>(slice)?;
let block = InterfaceDescriptionBlock {
linktype,
reserved,
snaplen,
options
};
Ok((slice, block))
}
}
#[derive(Clone, Debug, IntoOwned)]
pub enum InterfaceDescriptionOption<'a> {
Comment(Cow<'a, str>),
/// The if_name option is a UTF-8 string containing the name of the device used to capture data.
IfName(Cow<'a, str>),
/// The if_description option is a UTF-8 string containing the description of the device used to capture data.
IfDescription(Cow<'a, str>),
/// The if_IPv4addr option is an IPv4 network address and corresponding netmask for the interface.
IfIpv4Addr(Cow<'a, [u8]>),
/// The if_IPv6addr option is an IPv6 network address and corresponding prefix length for the interface.
IfIpv6Addr(Cow<'a, [u8]>),
/// The if_MACaddr option is the Interface Hardware MAC address (48 bits), if available.
IfMacAddr(Cow<'a, [u8]>),
/// The if_EUIaddr option is the Interface Hardware EUI address (64 bits), if available.
IfEuIAddr(u64),
/// The if_speed option is a 64-bit number for the Interface speed (in bits per second).
IfSpeed(u64),
/// The if_tsresol option identifies the resolution of timestamps.
IfTsResol(u8),
/// The if_tzone option identifies the time zone for GMT support.
IfTzone(u32),
/// The if_filter option identifies the filter (e.g. "capture only TCP traffic") used to capture traffic.
IfFilter(Cow<'a, [u8]>),
/// The if_os option is a UTF-8 string containing the name of the operating system
/// of the machine in which this interface is installed.
IfOs(Cow<'a, str>),
/// The if_fcslen option is an 8-bit unsigned integer value that specifies
/// the length of the Frame Check Sequence (in bits) for this interface.
IfFcsLen(u8),
/// The if_tsoffset option is a 64-bit integer value that specifies an offset (in seconds)
/// that must be added to the timestamp of each packet to obtain the absolute timestamp of a packet.
IfTsOffset(u64),
/// The if_hardware option is a UTF-8 string containing the description of the interface hardware.
IfHardware(Cow<'a, str>),
/// Custom option containing binary octets in the Custom Data portion
CustomBinary(CustomBinaryOption<'a>),
/// Custom option containing a UTF-8 string in the Custom Data portion
CustomUtf8(CustomUtf8Option<'a>),
/// Unknown option
Unknown(UnknownOption<'a>)
}
impl<'a> InterfaceDescriptionOption<'a> {
fn from_slice<B:ByteOrder>(slice: &'a[u8]) -> Result<(&'a[u8], Vec<Self>), PcapError> {
opts_from_slice::<B, _, _>(slice, |mut slice, code, length| {
let opt = match code {
1 => InterfaceDescriptionOption::Comment(Cow::Borrowed(std::str::from_utf8(slice)?)),
2 => InterfaceDescriptionOption::IfName(Cow::Borrowed(std::str::from_utf8(slice)?)),
3 => InterfaceDescriptionOption::IfDescription(Cow::Borrowed(std::str::from_utf8(slice)?)),
4 => {
if slice.len() != 8 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfIpv4Addr length != 8"))
}
InterfaceDescriptionOption::IfIpv4Addr(Cow::Borrowed(slice))
},
5 => {
if slice.len() != 17 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfIpv6Addr length != 17"))
}
InterfaceDescriptionOption::IfIpv6Addr(Cow::Borrowed(slice))
},
6 => {
if slice.len() != 6 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfMacAddr length != 6"))
}
InterfaceDescriptionOption::IfMacAddr(Cow::Borrowed(slice))
},
7 => {
if slice.len() != 8 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfEuIAddr length != 8"))
}
InterfaceDescriptionOption::IfEuIAddr(slice.read_u64::<B>()?)
},
8 => {
if slice.len() != 8 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfSpeed length != 8"))
}
InterfaceDescriptionOption::IfSpeed(slice.read_u64::<B>()?)
},
9 => {
if slice.len() != 1 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfTsResol length != 1"))
}
InterfaceDescriptionOption::IfTsResol(slice.read_u8()?)
},
10 => {
if slice.len() != 1 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfTzone length != 1"))
}
InterfaceDescriptionOption::IfTzone(slice.read_u32::<B>()?)
},
11 => {
if slice.is_empty() {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfFilter is empty"))
}
InterfaceDescriptionOption::IfFilter(Cow::Borrowed(slice))
},
12 => InterfaceDescriptionOption::IfOs(Cow::Borrowed(std::str::from_utf8(slice)?)),
13 => {
if slice.len() != 1 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfFcsLen length != 1"))
}
InterfaceDescriptionOption::IfFcsLen(slice.read_u8()?)
},
14 => {
if slice.len() != 8 {
return Err(PcapError::InvalidField("InterfaceDescriptionOption: IfTsOffset length != 8"))
}
InterfaceDescriptionOption::IfTsOffset(slice.read_u64::<B>()?)
},
15 => InterfaceDescriptionOption::IfHardware(Cow::Borrowed(std::str::from_utf8(slice)?)),
2988 | 19372 => InterfaceDescriptionOption::CustomUtf8(CustomUtf8Option::from_slice::<B>(code, slice)?),
2989 | 19373 => InterfaceDescriptionOption::CustomBinary(CustomBinaryOption::from_slice::<B>(code, slice)?),
_ => InterfaceDescriptionOption::Unknown(UnknownOption::new(code, length, slice))
};
Ok(opt)
})
}
}