frameassembly 1.0.1

A Domain-Specific Language (DSL) for writing deterministic network traffic to .pcap files.
Documentation
//! TACACS+ Layer 7 authentication 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_str_val, parse_u64, tag, ParsedField, Stream};

/// Parses a TACACS+ protocol declaration or session field.
pub(crate) fn parse_tacacs_field<'i, 'a>(input: &mut Stream<'i, 'a>) -> PResult<ParsedField<'a>> {
    alt((
        alt((
            tag(Token::Tacacs).map(|(_, s)| ParsedField::Protocol(Protocol::Tacacs, (s.start, s.len()))),
            (
                tag(Token::Type),
                cut_err(alt((
                    tag(Token::Authen).value("AUTHEN"),
                    tag(Token::Author).value("AUTHOR"),
                    tag(Token::Acct).value("ACCT"),
                    parse_str_val,
                ))),
            )
                .map(|((_, s), v)| ParsedField::L7StringField("TACACS_TYPE", v, (s.start, s.end - s.start))),
            tag(Token::Authen).map(|(_, s)| ParsedField::L7StringField("TACACS_TYPE", "AUTHEN", (s.start, s.len()))),
            tag(Token::Author).map(|(_, s)| ParsedField::L7StringField("TACACS_TYPE", "AUTHOR", (s.start, s.len()))),
        )),
        alt((
            tag(Token::Acct).map(|(_, s)| ParsedField::L7StringField("TACACS_TYPE", "ACCT", (s.start, s.len()))),
            (tag(Token::SessionId), cut_err(parse_u64)).map(|((_, s), v)| ParsedField::L7U64Field("SESSION_ID", v, (s.start, s.end - s.start))),
            (tag(Token::Data), cut_err(parse_str_val)).map(|((_, s), v)| ParsedField::L7StringField("DATA", v, (s.start, s.end - s.start))),
            (tag(Token::User), cut_err(parse_str_val)).map(|((_, s), v)| ParsedField::User(v, (s.start, s.end - s.start))),
        )),
    ))
    .parse_next(input)
}