frameassembly 1.0.0

A Domain-Specific Language (DSL) for writing deterministic network traffic to .pcap files.
Documentation 
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

//! ICMP Layer 3 protocol field parser.

use winnow::ModalResult as PResult;
use winnow::combinator::{alt, cut_err};
use winnow::prelude::*;

use crate::ast::*;
use crate::lexer::Token;
use crate::parser::{parse_ip, parse_u16, parse_u32, tag, ParsedField, Stream};

/// Parses an ICMP protocol declaration or message field.
pub(crate) fn parse_icmp_field<'i, 'a>(input: &mut Stream<'i, 'a>) -> PResult<ParsedField<'a>> {
    alt((
        alt((
            tag(Token::Icmp).map(|(_, s)| ParsedField::Protocol(Protocol::Icmp, (s.start, s.len()))),
            tag(Token::EchoRequest).map(|(_, s)| ParsedField::IcmpTypeChoice(IcmpTypeChoice::EchoRequest, (s.start, s.len()))),
            tag(Token::EchoReply).map(|(_, s)| ParsedField::IcmpTypeChoice(IcmpTypeChoice::EchoReply, (s.start, s.len()))),
            tag(Token::DestUnreach).map(|(_, s)| ParsedField::IcmpTypeChoice(IcmpTypeChoice::DestUnreach, (s.start, s.len()))),
            tag(Token::TimeExceeded).map(|(_, s)| ParsedField::IcmpTypeChoice(IcmpTypeChoice::TimeExceeded, (s.start, s.len()))),
            tag(Token::Redirect).map(|(_, s)| ParsedField::IcmpTypeChoice(IcmpTypeChoice::Redirect, (s.start, s.len()))),
        )),
        alt((
            (tag(Token::Gateway), cut_err(parse_ip)).map(|((_, s), v)| ParsedField::Gateway(v, (s.start, s.end - s.start))),
            (tag(Token::Code), parse_u32).map(|((_, s), v)| ParsedField::L7U32Field("CODE", v, (s.start, s.end - s.start))),
            (tag(Token::Id), cut_err(parse_u16)).map(|((_, s), v)| ParsedField::IcmpId(v, (s.start, s.end - s.start))),
            (tag(Token::Seq), cut_err(parse_u32)).map(|((_, s), v)| ParsedField::Seq(v, (s.start, s.end - s.start))),
        )),
    ))
    .parse_next(input)
}