Struct Tlv

pub struct Tlv { /* private fields */ }

BER-TLV structure, following ISO/IEC 7816-4.

BER-TLV data objects

Each BER-TLV data object consists of two or three consecutive fields (see the basic encoding rules of ASN.1 in ISO/IEC 8825-1): a mandatory tag field, a mandatory length field and a conditional value field.

• The tag field consists of one or more consecutive bytes. It indicates a class and an encoding and it encodes a tag number. The value ‘00’ is invalid for the first byte of tag fields (see ISO/IEC 8825-1).
• The length field consists of one or more consecutive bytes. It encodes a length, i.e., a number denoted N.
• If N is zero, there is no value field, i.e., the data object is empty. Otherwise (N > 0), the value field consists of N consecutive bytes.

Implementations

impl Tlv

pub fn new(tag: Tag, value: Value) -> Result<Self, TlvError>

Create a BER-TLV data object from valid tag and value.alloc

Errors

Fails with TlvError::Inconsistant if the tag indicates a contructed value (resp. primitive) and the value is primitive (resp. contructed).

pub fn tag(&self) -> &Tag

Get BER-TLV tag.

pub fn length(&self) -> usize

Get BER-TLV value length

pub fn value(&self) -> &Value

Get BER-TLV value

pub fn to_vec(&self) -> Vec<u8>

serializes self into a byte vector.

pub fn parse(input: &[u8]) -> (Result<Self, TlvError>, &[u8])

Parses a byte array into a BER-TLV structure. This also returns the unprocessed data.

pub fn parse_all(input: &[u8]) -> Vec<Self>

Parses a byte array into a vector of BER-TLV.

Note

Errors are discarded and parsing stops at first error Prefer using the parse() method and iterate over returned processed data.

pub fn from_bytes(input: &[u8]) -> Result<Self, TlvError>

Parses a byte array into a BER-TLV structure. Input must exactly match a BER-TLV object.

Errors

Fails with TlvError::InvalidInput if input does not match a BER-TLV object.

pub fn find(&self, tag: &Tag) -> Option<&Self>

Finds first occurence of a TLV object with given tag in self.

pub fn find_all(&self, tag: &Tag) -> Vec<&Self>

find all occurences of TLV objects with given given tag in self. Note that searching ContextSpecific class tag (0x80 for instance) will return a vector of possibly unrelated tlv data.

Trait Implementations

impl Clone for Tlv

fn clone(&self) -> Tlv

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Tlv

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

Formats the value using the given formatter.

impl Display for Tlv

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

Formats the value using the given formatter.

impl PartialEq for Tlv

fn eq(&self, other: &Tlv) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Tlv