frameassembly 1.0.0

A Domain-Specific Language (DSL) for writing deterministic network traffic to .pcap files.
Documentation 
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//! NTP Layer 7 clock synchronization 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_i32, parse_str_val, parse_u32, parse_u64, tag, ParsedField, Stream};

/// Parses an NTP protocol declaration or time synchronization field.
pub(crate) fn parse_ntp_field<'i, 'a>(input: &mut Stream<'i, 'a>) -> PResult<ParsedField<'a>> {
    alt((
        alt((
            tag(Token::Ntp).map(|(_, s)| ParsedField::Protocol(Protocol::Ntp, (s.start, s.len()))),
            (tag(Token::Li), cut_err(parse_u32)).map(|((_, s), v)| ParsedField::L7U32Field("LI", v, (s.start, s.end - s.start))),
            (tag(Token::Vn), cut_err(parse_u32)).map(|((_, s), v)| ParsedField::L7U32Field("VN", v, (s.start, s.end - s.start))),
            (tag(Token::Mode), parse_u32).map(|((_, s), v)| ParsedField::L7U32Field("MODE", v, (s.start, s.end - s.start))),
            (tag(Token::Stratum), cut_err(parse_u32)).map(|((_, s), v)| ParsedField::L7U32Field("STRATUM", v, (s.start, s.end - s.start))),
        )),
        alt((
            (tag(Token::Poll), cut_err(parse_u32)).map(|((_, s), v)| ParsedField::L7U32Field("POLL", v, (s.start, s.end - s.start))),
            (tag(Token::Precision), cut_err(parse_i32)).map(|((_, s), v)| ParsedField::L7U32Field("PRECISION", v as u32, (s.start, s.end - s.start))),
            (tag(Token::RefId), cut_err(parse_str_val)).map(|((_, s), v)| ParsedField::L7StringField("REFID", v, (s.start, s.end - s.start))),
            (tag(Token::TxTimestamp), cut_err(parse_u64)).map(|((_, s), v)| ParsedField::L7U64Field("TX_TIMESTAMP", v, (s.start, s.end - s.start))),
        )),
    ))
    .parse_next(input)
}