-
Notifications
You must be signed in to change notification settings - Fork 5
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
feat: add SCION SCMP packet definitions
- Loading branch information
Showing
12 changed files
with
344 additions
and
36 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,138 @@ | ||
| //! SCION packets containing SCMP messages. | ||
| use bytes::{Buf, Bytes}; | ||
|
|
||
| use super::{error::ScmpEncodeError, InadequateBufferSize, ScionHeaders, ScionPacketRaw}; | ||
| use crate::{ | ||
| address::ScionAddr, | ||
| packet::ByEndpoint, | ||
| path::{DataplanePath, Path}, | ||
| scmp::{ScmpDecodeError, ScmpMessage, ScmpTracerouteRequest, ScmpType, SCMP_PROTOCOL_NUMBER}, | ||
| wire_encoding::{WireDecode, WireEncodeVec}, | ||
| }; | ||
|
|
||
| /// A SCION packet containing a SCMP message. | ||
| #[derive(Debug, Clone, PartialEq)] | ||
| pub struct ScionPacketScmp { | ||
| /// Packet headers | ||
| pub headers: ScionHeaders, | ||
| /// The contained SCMP message | ||
| pub message: ScmpMessage, | ||
| } | ||
|
|
||
| impl ScionPacketScmp { | ||
| /// Returns the SCMP message type. | ||
| pub fn get_type(&self) -> ScmpType { | ||
| self.message.get_type() | ||
| } | ||
| } | ||
|
|
||
| /// The position of a router for a given hop in forwarding direction. | ||
| pub enum RouterPosition { | ||
| /// The ingress router in forwarding direction. | ||
| Ingress, | ||
| /// The egress router in forwarding direction. | ||
| Egress, | ||
| } | ||
|
|
||
| impl ScionPacketScmp { | ||
| /// Creates a new SCION SCMP packet based on the SCMP message correctly setting the checksum. | ||
| /// | ||
| /// This does not work for an [`ScmpTracerouteRequest`] message, which requires setting specific | ||
| /// router alert flags. Use [`Self::new_traceroute_request`] for this purpose. | ||
| pub fn new( | ||
| endhosts: &ByEndpoint<ScionAddr>, | ||
| path: &Path, | ||
| mut message: ScmpMessage, | ||
| ) -> Result<Self, ScmpEncodeError> { | ||
| let headers = | ||
| ScionHeaders::new(endhosts, path, SCMP_PROTOCOL_NUMBER, message.total_length())?; | ||
| message.set_checksum(&headers.address); | ||
|
|
||
| Ok(Self { headers, message }) | ||
| } | ||
|
|
||
| /// Creates a new SCION packet containing an [`ScmpTracerouteRequest`]. | ||
| /// | ||
| /// This correctly sets the appropriate router alert flags and checksum. | ||
| pub fn new_traceroute_request( | ||
| endhosts: &ByEndpoint<ScionAddr>, | ||
| path: &Path, | ||
| identifier: u16, | ||
| sequence_number: u16, | ||
| hop_index: usize, | ||
| router_position: RouterPosition, | ||
| ) -> Result<Self, ScmpEncodeError> { | ||
| let DataplanePath::Standard(ref standard_path) = path.dataplane_path else { | ||
| return Err(ScmpEncodeError::InappropriatePathType); | ||
| }; | ||
| let mut standard_path_mut = standard_path.to_mut(); | ||
| let Some(hop_field) = standard_path_mut.hop_field_mut(hop_index) else { | ||
| return Err(ScmpEncodeError::ParameterOutOfRange); | ||
| }; | ||
| match router_position { | ||
| RouterPosition::Ingress => hop_field.set_cons_ingress_router_alert(true), | ||
| RouterPosition::Egress => hop_field.set_cons_egress_router_alert(true), | ||
| }; | ||
|
|
||
| let path = Path { | ||
| dataplane_path: DataplanePath::Standard(standard_path_mut.freeze()), | ||
| underlay_next_hop: path.underlay_next_hop, | ||
| isd_asn: path.isd_asn, | ||
| metadata: None, | ||
| }; | ||
| let packet = Self::new( | ||
| endhosts, | ||
| &path, | ||
| ScmpTracerouteRequest::new(identifier, sequence_number).into(), | ||
| )?; | ||
|
|
||
| Ok(packet) | ||
| } | ||
| } | ||
|
|
||
| impl TryFrom<ScionPacketRaw> for ScionPacketScmp { | ||
| type Error = ScmpDecodeError; | ||
|
|
||
| fn try_from(mut value: ScionPacketRaw) -> Result<Self, Self::Error> { | ||
| if value.headers.common.next_header != SCMP_PROTOCOL_NUMBER { | ||
| return Err(ScmpDecodeError::WrongProtocolNumber( | ||
| value.headers.common.next_header, | ||
| )); | ||
| } | ||
| Ok(Self { | ||
| headers: value.headers, | ||
| message: ScmpMessage::decode(&mut value.payload)?, | ||
| }) | ||
| } | ||
| } | ||
|
|
||
| impl<T: Buf> WireDecode<T> for ScionPacketScmp { | ||
| type Error = ScmpDecodeError; | ||
|
|
||
| fn decode(data: &mut T) -> Result<Self, Self::Error> { | ||
| ScionPacketRaw::decode(data)?.try_into() | ||
| } | ||
| } | ||
|
|
||
| impl WireEncodeVec<3> for ScionPacketScmp { | ||
| type Error = InadequateBufferSize; | ||
|
|
||
| fn encode_with_unchecked(&self, buffer: &mut bytes::BytesMut) -> [Bytes; 3] { | ||
| let encoded_headers = self.headers.encode_with_unchecked(buffer); | ||
| let encoded_message = self.message.encode_with_unchecked(buffer); | ||
| [ | ||
| encoded_headers[0].clone(), | ||
| encoded_message[0].clone(), | ||
| encoded_message[1].clone(), | ||
| ] | ||
| } | ||
|
|
||
| fn total_length(&self) -> usize { | ||
| self.headers.total_length() + self.message.total_length() | ||
| } | ||
|
|
||
| fn required_capacity(&self) -> usize { | ||
| self.headers.required_capacity() + self.message.required_capacity() | ||
| } | ||
| } |
Oops, something went wrong.