gbp/
control.rs

1//! GBP control plane message envelope. Six CBOR keys.
2
3use crate::CodecError;
4use serde::{Deserialize, Serialize};
5use serde_bytes::ByteBuf;
6
7/// Control plane message that travels on Stream 0.
8#[derive(Clone, Debug, Serialize, Deserialize)]
9pub struct ControlMessage {
10    /// Opcode (see `gbp_core::ControlOpcode`).
11    #[serde(rename = "op")]
12    pub opcode: u16,
13    /// Request identifier (echoed in ACK / NACK).
14    #[serde(rename = "rid")]
15    pub request_id: u32,
16    /// Sender's member id.
17    #[serde(rename = "sid")]
18    pub sender_id: u32,
19    /// Related `transition_id`.
20    #[serde(rename = "tid")]
21    pub transition_id: u32,
22    /// Declared length of [`args`](Self::args).
23    #[serde(rename = "alen")]
24    pub args_length: u32,
25    /// Opcode-specific CBOR arguments.
26    #[serde(rename = "args")]
27    pub args: ByteBuf,
28}
29
30impl ControlMessage {
31    /// Builds an argument-less message.
32    pub fn bare(opcode: u16, request_id: u32, sender_id: u32, transition_id: u32) -> Self {
33        Self {
34            opcode,
35            request_id,
36            sender_id,
37            transition_id,
38            args_length: 0,
39            args: ByteBuf::new(),
40        }
41    }
42
43    /// Builds a message with raw CBOR arguments.
44    pub fn with_args(
45        opcode: u16,
46        request_id: u32,
47        sender_id: u32,
48        transition_id: u32,
49        args: Vec<u8>,
50    ) -> Self {
51        Self {
52            opcode,
53            request_id,
54            sender_id,
55            transition_id,
56            args_length: args.len() as u32,
57            args: ByteBuf::from(args),
58        }
59    }
60
61    /// CBOR-encodes the message.
62    pub fn to_cbor(&self) -> Vec<u8> {
63        let mut buf = Vec::new();
64        ciborium::into_writer(self, &mut buf).expect("cbor encode");
65        buf
66    }
67
68    /// Decodes a CBOR-encoded message and validates `args_length`.
69    pub fn from_cbor(data: &[u8]) -> Result<Self, CodecError> {
70        let m: Self = ciborium::from_reader(data).map_err(|e| CodecError::Decode(e.to_string()))?;
71        if m.args_length as usize != m.args.len() {
72            return Err(CodecError::PayloadSizeMismatch);
73        }
74        Ok(m)
75    }
76}
gbp/control.rs

gbp/
control.rs
