Function der_parser::ber::parse_ber_container
source · pub fn parse_ber_container<'a, O, F, E>(
f: F
) -> impl FnMut(&'a [u8]) -> IResult<&'a [u8], O, E>where
F: FnMut(&'a [u8], Header<'a>) -> IResult<&'a [u8], O, E>,
E: ParseError<&'a [u8]> + From<BerError>,
Expand description
Parse a BER object and apply provided function to content
Given a parser for content, read BER object header and apply parser to return the remaining bytes and the parser result.
The remaining bytes point after the content: any bytes that are part of the content but not
parsed are ignored.
The nom combinator all_consuming
can be used to ensure all the content is parsed.
This function is mostly intended for constructed objects, but can be used for any valid BER object.
Examples
Parsing a defined sequence with different types:
pub struct MyObject<'a> {
a: u32,
b: &'a [u8],
}
/// Read a DER-encoded object:
/// SEQUENCE {
/// a INTEGER (0..4294967295),
/// b OCTETSTRING
/// }
fn parse_myobject(i: &[u8]) -> BerResult<MyObject> {
parse_ber_container(
|i: &[u8], hdr: Header| {
if hdr.tag() != Tag::Sequence {
return Err(nom::Err::Error(BerError::BerTypeError.into()));
}
let (i, a) = parse_ber_u32(i)?;
let (i, obj) = parse_ber_octetstring(i)?;
let b = obj.as_slice().unwrap();
Ok((i, MyObject{ a, b }))
}
)(i)
}
let (rem, v) = parse_myobject(&bytes).expect("parsing failed");