Struct Reader 

pub struct Reader<'a> { /* private fields */ }

A cursor over a DER input that yields borrowed value contents.

The reader is checked: every method validates the tag, the length, and the available input before returning, so it never panics on malformed data.

Implementations

impl<'a> Reader<'a>

pub const fn new(data: &'a [u8]) -> Self

Creates a reader over data.

pub fn is_empty(&self) -> bool

Returns true when all input has been consumed.

pub fn remaining(&self) -> usize

Returns the number of unread bytes.

pub fn peek_tag(&self) -> Result<u8, DerError>

Returns the tag of the next value without consuming it.

Returns DerError::Truncated when no value remains.

pub fn read_tlv(&mut self) -> Result<(u8, &'a [u8]), DerError>

Reads one tag-length-value, returning its tag and content.

Returns DerError when the value is truncated, uses an indefinite or non-minimal length, or has a high-tag-number form.

pub fn read_expected(&mut self, tag: u8) -> Result<&'a [u8], DerError>

Reads one value and requires it to have tag, returning its content.

pub fn read_sequence(&mut self) -> Result<Reader<'a>, DerError>

Reads a SEQUENCE and returns a reader over its content.

pub fn read_integer(&mut self) -> Result<&'a [u8], DerError>

Reads an INTEGER, returning its canonical content bytes.

The content may start with a single 0x00 when required to keep the sign bit clear. Empty or non-minimal encodings are rejected.

pub fn read_octet_string(&mut self) -> Result<&'a [u8], DerError>

Reads an OCTET STRING, returning its content bytes.

pub fn read_bit_string(&mut self) -> Result<&'a [u8], DerError>

Reads a BIT STRING, returning its bytes with the unused-bits count byte removed.

Returns DerError::Unsupported when the value declares unused bits (only byte-aligned bit strings are supported).

pub fn read_oid(&mut self) -> Result<&'a [u8], DerError>

Reads an OBJECT IDENTIFIER, returning its content bytes (without the leading tag/length). Compare against known OID byte strings.

pub fn read_explicit(&mut self, tag: u8) -> Result<Reader<'a>, DerError>

Reads a context-specific [tag] explicit wrapper and returns a reader over the wrapped value. tag is the full identifier byte, e.g. 0xa0.

pub fn finish(self) -> Result<(), DerError>

Asserts that all input was consumed.

Returns DerError::TrailingData otherwise.

Trait Implementations

impl<'a> Clone for Reader<'a>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> Debug for Reader<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.