Macro der_parser::parse_der_optional
source · macro_rules! parse_der_optional { ($i:expr, $f:ident) => { ... }; }
Expand description
Parse an optional DER element
Try to parse an optional DER element, and return it as a ContextSpecific
item with tag 0.
If the parsing failed, the ContextSpecific
object has value None
.
let empty = &b""[..];
let bytes1 = [ 0x30, 0x0a,
0x0a, 0x03, 0x00, 0x00, 0x01,
0x02, 0x03, 0x01, 0x00, 0x01];
let bytes2 = [ 0x30, 0x05,
0x02, 0x03, 0x01, 0x00, 0x01];
let expected1 = BerObject::from_seq(vec![
BerObject::from_obj(
BerObjectContent::ContextSpecific(BerTag(0),
Some(Box::new(BerObject::from_obj(BerObjectContent::Enum(1)))))
),
BerObject::from_int_slice(b"\x01\x00\x01"),
]);
let expected2 = BerObject::from_seq(vec![
BerObject::from_obj(
BerObjectContent::ContextSpecific(BerTag(0), None),
),
BerObject::from_int_slice(b"\x01\x00\x01"),
]);
fn parse_optional_enum(i:&[u8]) -> BerResult {
parse_der_optional!(i, parse_ber_enum)
}
fn parser(i:&[u8]) -> BerResult {
parse_der_sequence_defined_m!(i,
parse_optional_enum >>
parse_ber_integer
)
};
assert_eq!(parser(&bytes1), Ok((empty, expected1)));
assert_eq!(parser(&bytes2), Ok((empty, expected2)));