Skip to content

Commit

Permalink
Make the Unimplemented variants so that we can actually compose and p…
Browse files Browse the repository at this point in the history 
…ropagate them
  • Loading branch information
@DRiKE
DRiKE committed Aug 29, 2023
1 parent 48f56e2 commit 3870650
Show file tree
Hide file tree
Showing 2 changed files with 204 additions and 14 deletions.
1 change: 1 addition & 0 deletions src/bgp/communities.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -767,6 +767,7 @@ impl From<[u8; 8]> for Community {
Community::Extended(ExtendedCommunity(raw))
}
}

impl From<[u8; 8]> for ExtendedCommunity {
fn from(raw: [u8; 8]) -> ExtendedCommunity {
ExtendedCommunity(raw)
Expand Down
217 changes: 203 additions & 14 deletions src/bgp/message/update_builder.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -26,7 +26,8 @@ pub mod new_pas {
use crate::bgp::types::{AFI, SAFI};
use crate::util::parser::{ParseError, parse_ipv4addr};

struct Flags { }
#[derive(Copy, Clone, Debug, Eq, PartialEq)]
pub struct Flags(u8);

impl Flags {
// 0 1 2 3 4 5 6 7
Expand All @@ -42,8 +43,42 @@ pub mod new_pas {

const EXTENDED_LEN: u8 = 0b0001_0000;
const PARTIAL: u8 = 0b0010_0000;

/// Returns true if the optional flag is set.
pub fn is_optional(self) -> bool {
self.0 & 0x80 == 0x80
}

/// Returns true if the transitive bit is set.
pub fn is_transitive(self) -> bool {
self.0 & 0x40 == 0x40
}

/// Returns true if the partial flag is set.
pub fn is_partial(self) -> bool {
self.0 & 0x20 == 0x20
}

/// Returns true if the extended length flag is set.
pub fn is_extended_length(self) -> bool {
self.0 & 0x10 == 0x10
}

}

impl From<u8> for Flags {
fn from(u: u8) -> Flags {
Flags(u)
}
}

impl From<Flags> for u8 {
fn from(f: Flags) -> u8 {
f.0
}
}


pub trait AttributeHeader {
const FLAGS: u8;
const TYPECODE: u8;
Expand Down Expand Up @@ -80,7 +115,8 @@ pub mod new_pas {
#[derive(Debug, Eq, PartialEq)]
pub enum PathAttribute {
$( $name($name) ),+,
Unimplemented(u8)
//Unimplemented(Flags, u8, Vec<u8>)
Unimplemented(UnimplementedPathAttribute)
}

impl PathAttribute {
Expand All @@ -94,7 +130,7 @@ pub mod new_pas {
PathAttribute::$name(i) => i.compose(target)
),+,
//PathAttribute::Unimplemented(i) => TODO return Err(ComposeError) ?
PathAttribute::Unimplemented(_i) => unimplemented!()
PathAttribute::Unimplemented(u) => u.compose(target)
}
}

Expand All @@ -104,9 +140,8 @@ pub mod new_pas {
PathAttribute::$name(_) =>
PathAttributeType::$name
),+,
PathAttribute::Unimplemented(i) =>
PathAttributeType::Unimplemented(*i)

PathAttribute::Unimplemented(u) =>
PathAttributeType::Unimplemented(u.typecode())
}
}
}
Expand All @@ -119,10 +154,16 @@ pub mod new_pas {
}
)+

impl From<UnimplementedPathAttribute> for PathAttribute {
fn from(u: UnimplementedPathAttribute) -> PathAttribute {
PathAttribute::Unimplemented(u)
}
}

#[derive(Debug)]
pub enum WireformatPathAttribute<'a, Octs> {
$( $name(Parser<'a, Octs>, SessionConfig) ),+,
Unimplemented(u8)
Unimplemented(UnimplementedWireformat<'a, Octs>)
}


Expand All @@ -147,7 +188,10 @@ pub mod new_pas {
$typecode => WireformatPathAttribute::$name(pp, sc)
),+
,
_ => WireformatPathAttribute::Unimplemented(typecode)
_ => WireformatPathAttribute::Unimplemented(
UnimplementedWireformat::new(
flags.into(), typecode, pp
))
};

Ok(res)
Expand All @@ -165,8 +209,14 @@ pub mod new_pas {
)
}
),+,
WireformatPathAttribute::Unimplemented(i) => {
PathAttribute::Unimplemented(*i)
WireformatPathAttribute::Unimplemented(u) => {
PathAttribute::Unimplemented(
UnimplementedPathAttribute::new(
u.flags(),
u.typecode(),
u.value().to_vec()
)
)
}
}
}
Expand All @@ -177,8 +227,8 @@ pub mod new_pas {
WireformatPathAttribute::$name(_,_) =>
PathAttributeType::$name
),+,
WireformatPathAttribute::Unimplemented(i) =>
PathAttributeType::Unimplemented(*i)
WireformatPathAttribute::Unimplemented(u) =>
PathAttributeType::Unimplemented(u.typecode())
}
}
}
Expand All @@ -192,7 +242,7 @@ pub mod new_pas {
fn from(code: u8) -> PathAttributeType {
match code {
$( $typecode => PathAttributeType::$name ),+,
_ => unimplemented!() // TODO
u => PathAttributeType::Unimplemented(u)
}
}
}
Expand Down Expand Up @@ -231,7 +281,7 @@ pub mod new_pas {
20 => Connector(Ipv4Addr), Flags::OPT_TRANS,
21 => AsPathLimit(AsPathLimitInfo), Flags::OPT_TRANS,
//22 => PmsiTunnel(todo), Flags::OPT_TRANS,
// , 25 old PathAttributeType
// , 25 ExtIpv6Comm
32 => LargeCommunities(LargeCommunitiesList), Flags::OPT_TRANS,
// 33 => BgpsecAsPath,
35 => Otc(Asn), Flags::OPT_TRANS,
Expand All @@ -240,6 +290,79 @@ pub mod new_pas {

);

#[derive(Debug, Eq, PartialEq)]
pub struct UnimplementedPathAttribute {
flags: Flags,
typecode: u8,
value: Vec<u8>,
}

impl UnimplementedPathAttribute {
pub fn new(flags: Flags, typecode: u8, value: Vec<u8>) -> Self {
Self { flags, typecode, value }
}

pub fn typecode(&self) -> u8 {
self.typecode
}

pub fn flags(&self) -> Flags {
self.flags
}

pub fn value(&self) -> &Vec<u8> {
&self.value
}
}

#[derive(Debug)]
pub struct UnimplementedWireformat<'a, Octs> {
flags: Flags,
typecode: u8,
value: Parser<'a, Octs>,
}

impl<'a, Octs: Octets> UnimplementedWireformat<'a, Octs> {
pub fn new(flags: Flags, typecode: u8, value: Parser<'a, Octs>) -> Self {
Self { flags, typecode, value }
}
pub fn typecode(&self) -> u8 {
self.typecode
}

pub fn flags(&self) -> Flags {
self.flags
}

pub fn value(&self) -> &[u8] {
self.value.peek_all()
}

/* TODO move these to all (wireformat)pathattributes
/// Returns true if the optional flag is set.
pub fn is_optional(self) -> bool {
self.0 & 0x80 == 0x80
}
/// Returns true if the transitive bit is set.
pub fn is_transitive(&self) -> bool {
self.flags.is_transitive()
}
/// Returns true if the partial flag is set.
pub fn is_partial(&self) -> bool {
self.flags.is_partial()
}
/// Returns true if the extended length flag is set.
pub fn is_extended_length(&self) -> bool {
self.flags.is_extended_length()
}
*/

}


pub trait Attribute: AttributeHeader {

fn compose_len(&self) -> usize {
Expand Down Expand Up @@ -970,6 +1093,38 @@ pub mod new_pas {
}


//--- Unimplemented
//
// XXX implementing the Attribute trait requires to implement the
// AttributeHeader trait to be implemented as well. But, we have no const
// FLAGS and TYPECODE for an UnimplementedPathAttribute, so that does not
// fly.
//
// Let's try to go without the trait.

impl UnimplementedPathAttribute {
fn compose<Target: OctetsBuilder>(&self, target: &mut Target)
-> Result<(), Target::AppendError>
{
let len = self.value().len();
target.append_slice(
&[self.flags().into(), self.typecode().into()]

Check failure on line 1111 in src/bgp/message/update_builder.rs

View workflow job for this annotation

GitHub Actions / test (ubuntu-latest, stable) 

useless conversion to the same type: `u8`

Check failure on line 1111 in src/bgp/message/update_builder.rs

View workflow job for this annotation

GitHub Actions / test (ubuntu-latest, nightly) 

useless conversion to the same type: `u8`
)?;
if self.flags().is_extended_length() {
target.append_slice(
&u16::try_from(len).unwrap_or(u16::MAX)
.to_be_bytes()
)?;
} else {
target.append_slice(&[
u8::try_from(len).unwrap_or(u8::MAX)
])?;
}
target.append_slice(&self.value())

Check failure on line 1123 in src/bgp/message/update_builder.rs

View workflow job for this annotation

GitHub Actions / test (ubuntu-latest, stable) 

this expression creates a reference which is immediately dereferenced by the compiler

Check failure on line 1123 in src/bgp/message/update_builder.rs

View workflow job for this annotation

GitHub Actions / test (ubuntu-latest, nightly) 

this expression creates a reference which is immediately dereferenced by the compiler
}
}


//------------ Tests ---------------------------------------------------------

#[cfg(test)]
Expand All @@ -980,6 +1135,8 @@ pub mod new_pas {
use crate::bgp::message::nlri::Nlri;
use crate::bgp::message::update::NextHop;

// FIXME switch to use ::new() for all attributes instead of relying
// on non public newtype constructor
#[test]
fn wireformat_to_owned_and_back() {
use super::PathAttribute as PA;
Expand Down Expand Up @@ -1190,6 +1347,18 @@ pub mod new_pas {
);


// UnimplementedPathAttribute
check(
vec![0xc0, 254, 0x04, 0x01, 0x02, 0x03, 0x04],
UnimplementedPathAttribute::new(
Flags::OPT_TRANS.into(),
254,
vec![0x01, 0x02, 0x03, 0x04]
).into()
);



}

#[test]
Expand All @@ -1212,6 +1381,26 @@ pub mod new_pas {
assert!(pas.get(PathAttributeType::MultiExitDisc).is_some());
assert!(pas.get(PathAttributeType::NextHop).is_some());
}

#[test]
fn unimplemented_path_attributes() {
let raw = vec![
0xc0, 254, 0x04, 0x01, 0x02, 0x03, 0x04
];
let mut parser = Parser::from_ref(&raw);
let sc = SessionConfig::modern();
let pa = WireformatPathAttribute::parse(&mut parser, sc);

if let Ok(WireformatPathAttribute::Unimplemented(u)) = pa {
assert_eq!(u.typecode(), 254);
assert!(u.flags().is_optional());
assert!(u.flags().is_transitive());
assert_eq!(u.value(), &[0x01, 0x02, 0x03, 0x04]);
} else {
panic!("fail");
}

}
}
}

Expand Down

0 comments on commit 3870650

Please sign in to comment.