Module rosenpass::msgs

Data structures representing the messages going over the wire

This module contains de-/serialization of the protocol’s messages. Thats kind of a lie, since no actual ser/de happens. Instead, the structures offer views into mutable byte slices (&mut [u8]), allowing to modify the fields of an always serialized instance of the data in question. This is closely related to the concept of lenses in function programming; more on that here: https://sinusoid.es/misc/lager/lenses.pdf

Example

The following example uses the data_lense macro to create a lense that might be useful when dealing with UDP headers.

use rosenpass::{data_lense, RosenpassError, msgs::LenseView};

data_lense! {UdpDatagramHeader :=
    source_port: 2,
    dest_port: 2,
    length: 2,
    checksum: 2
}

let mut buf = [0u8; 8];

// read-only lense, no check of size:
let lense = UdpDatagramHeader(&buf);
assert_eq!(lense.checksum(), &[0, 0]);

// mutable lense, runtime check of size
let mut lense = buf.as_mut().udp_datagram_header()?;
lense.source_port_mut().copy_from_slice(&53u16.to_be_bytes()); // some DNS, anyone?

// the original buffer is still available
assert_eq!(buf, [0, 53, 0, 0, 0, 0, 0, 0]);

// read-only lense, runtime check of size
let lense = buf.as_ref().udp_datagram_header()?;
assert_eq!(lense.source_port(), &[0, 53]);

Structs

• Biscuit
  A data lense to manipulate byte slices.
• CookieReply
  A data lense to manipulate byte slices.
• DataMsg
  A data lense to manipulate byte slices.
• EmptyData
  A data lense to manipulate byte slices.
• Envelope
  A data lense to manipulate byte slices.
• InitConf
  A data lense to manipulate byte slices.
• InitHello
  A data lense to manipulate byte slices.
• RespHello
  A data lense to manipulate byte slices.

Enums

• MsgType
  Recognized message types

Constants

• BISCUIT_CT_LEN
  Length in bytes of an encrypted Biscuit (cipher text)
• BISCUIT_ID_LEN
• BISCUIT_PT_LEN
  length in bytes of an unencrypted Biscuit (plain text)
• MAX_MESSAGE_LEN
  Size required to fit any message in binary form
• SESSION_ID_LEN
• WIRE_ENVELOPE_LEN

Traits

• BiscuitExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a Biscuit
• CookieReplyExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a CookieReply
• DataMsgExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a DataMsg
• EmptyDataExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a EmptyData
• EnvelopeExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a Envelope
• InitConfExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a InitConf
• InitHelloExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a InitHello
• LenseView
  Common trait shared by all Lenses
• RespHelloExt
  Extension trait to allow checked creation of a lense over some byte slice that contains a RespHello
• WireMsg