bgpkit_parser/parser/bmp/messages/
termination_message.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
use crate::parser::bmp::error::ParserBmpError;
use crate::parser::ReadUtils;
use bytes::{Buf, Bytes};
use num_enum::{IntoPrimitive, TryFromPrimitive};
use std::convert::TryFrom;

#[derive(Debug, PartialEq, Clone)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct TerminationMessage {
    pub tlvs: Vec<TerminationTlv>,
}

#[derive(Debug, PartialEq, Clone)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub struct TerminationTlv {
    pub info_type: TerminationTlvType,
    pub info_len: u16,
    pub info_value: TerminationTlvValue,
}

#[derive(Debug, PartialEq, Clone)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
pub enum TerminationTlvValue {
    String(String),
    Reason(TerminationReason),
}

#[derive(Debug, TryFromPrimitive, IntoPrimitive, PartialEq, Clone, Copy)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[repr(u16)]
pub enum TerminationReason {
    AdministrativelyClosed = 0,
    UnspecifiedReason = 1,
    OutOfResources = 2,
    RedundantConnection = 3,
    PermanentlyAdministrativelyClosed = 4,
}

///Type-Length-Value Type
///
/// For more, see: https://datatracker.ietf.org/doc/html/rfc1213
#[derive(Debug, TryFromPrimitive, IntoPrimitive, PartialEq, Clone, Copy)]
#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[repr(u16)]
pub enum TerminationTlvType {
    String = 0,
    Reason = 1,
}

pub fn parse_termination_message(data: &mut Bytes) -> Result<TerminationMessage, ParserBmpError> {
    let mut tlvs = vec![];

    while data.remaining() > 4 {
        let info_type: TerminationTlvType = TerminationTlvType::try_from(data.read_u16()?)?;
        let info_len = data.read_u16()?;
        if data.remaining() < info_len as usize {
            // not enough bytes to read
            break;
        }
        let info_value = match info_type {
            TerminationTlvType::String => {
                let info = data.read_n_bytes_to_string(info_len as usize)?;
                TerminationTlvValue::String(info)
            }
            TerminationTlvType::Reason => {
                let reason = TerminationReason::try_from(data.read_u16()?)?;
                TerminationTlvValue::Reason(reason)
            }
        };
        tlvs.push(TerminationTlv {
            info_type,
            info_len,
            info_value,
        })
    }

    Ok(TerminationMessage { tlvs })
}

#[cfg(test)]
mod tests {
    use super::*;
    use bytes::Bytes;

    #[test]
    fn test_parse_termination_message() {
        // Create a Bytes object to simulate the incoming data
        let mut data = Bytes::copy_from_slice(&[
            0, 0, // info_type: String
            0, 5, // info_len: 5
            67, 79, 68, 69, 83, // info: "CODES"
            0, 1, // info_type: Reason
            0, 2, // info_len: 2
            0, 1, // info: UnspecifiedReason
        ]);

        // Check if parse_termination_message correctly reads the data
        let result = parse_termination_message(&mut data);
        match result {
            Ok(termination_message) => {
                assert_eq!(termination_message.tlvs.len(), 2);

                // tlvs[0] assertions
                assert_eq!(
                    termination_message.tlvs[0].info_type,
                    TerminationTlvType::String
                );
                assert_eq!(termination_message.tlvs[0].info_len, 5);
                assert_eq!(
                    termination_message.tlvs[0].info_value,
                    TerminationTlvValue::String("CODES".to_string())
                );

                // tlvs[1] assertions
                assert_eq!(
                    termination_message.tlvs[1].info_type,
                    TerminationTlvType::Reason
                );
                assert_eq!(termination_message.tlvs[1].info_len, 2);
                assert_eq!(
                    termination_message.tlvs[1].info_value,
                    TerminationTlvValue::Reason(TerminationReason::UnspecifiedReason)
                );
            }
            Err(e) => panic!("Failed to parse: {}", e),
        }
    }
}