Trait EncodeValue 

pub trait EncodeValue {
    // Required methods
    fn value_len(&self) -> Result<Length, Error>;
    fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>;

    // Provided method
    fn header(&self) -> Result<Header, Error>
       where Self: Tagged { ... }
}

Available on crate feature pkcs8 only.

Encode the value part of a Tag-Length-Value encoded field, sans the [Tag] and Length.

As opposed to Encode, implementer is expected to write the inner content only, without the Header.

When EncodeValue is paired with [FixedTag], it produces a complete TLV ASN.1 DER encoding as Encode trait.

Example

use der::{Encode, EncodeValue, ErrorKind, FixedTag, Length, Tag, Writer};

/// 1-byte month
struct MyByteMonth(u8);

impl EncodeValue for MyByteMonth {

    fn value_len(&self) -> der::Result<Length> {
        Ok(Length::new(1))
    }

    fn encode_value(&self, writer: &mut impl Writer) -> der::Result<()> {
        writer.write_byte(self.0)?;
        Ok(())
    }
}

impl FixedTag for MyByteMonth {
    const TAG: Tag = Tag::OctetString;
}

let month = MyByteMonth(9);
let mut buf = [0u8; 16];
let month_der = month.encode_to_slice(&mut buf).expect("month to encode");

assert_eq!(month_der, b"\x04\x01\x09");

Required Methods

fn value_len(&self) -> Result<Length, Error>

Compute the length of this value (sans [Tag]+Length header) when encoded as ASN.1 DER.

Errors

Returns an error if the value length could not be computed (e.g. overflow).

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

Encode value (sans [Tag]+Length header) as ASN.1 DER using the provided Writer.

Errors

In the event an encoding error occurred.

Provided Methods

fn header(&self) -> Result<Header, Error>

where Self: Tagged,

Get the Header used to encode this value.

Errors

Returns an error if the header could not be computed.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl EncodeValue for bool

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for i8

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for i16

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for i32

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for i64

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for i128

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for str

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for u8

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for u16

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for u32

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for u64

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for u128

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for ()

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, _writer: &mut impl Writer) -> Result<(), Error>

impl EncodeValue for String

Available on crate feature alloc only.

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl<T> EncodeValue for Cow<'_, T>

where T: ToOwned + ?Sized, &'a T: for<'a> EncodeValue,

Available on crate feature alloc only.

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl<T> EncodeValue for [T]

where T: Encode,

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl<T> EncodeValue for Box<T>

where T: EncodeValue,

Available on crate feature alloc only.

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl<T> EncodeValue for Vec<T>

where T: Encode,

Available on crate feature alloc only.

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

impl<T, const N: usize> EncodeValue for [T; N]

where T: Encode,

fn value_len(&self) -> Result<Length, Error>

fn encode_value(&self, writer: &mut impl Writer) -> Result<(), Error>

Implementors

impl EncodeValue for &OctetStringRef

impl EncodeValue for BitString

impl EncodeValue for BitStringRef<'_>

impl EncodeValue for BmpString

impl EncodeValue for GeneralStringRef<'_>

impl EncodeValue for GeneralizedTime

impl EncodeValue for Ia5String

impl EncodeValue for Int

impl EncodeValue for IntRef<'_>

impl EncodeValue for Null

impl EncodeValue for OctetString

impl EncodeValue for PrintableString

impl EncodeValue for SequenceRef

impl EncodeValue for TeletexString

impl EncodeValue for Uint

impl EncodeValue for UintRef<'_>

impl EncodeValue for UtcTime

impl EncodeValue for Any

impl EncodeValue for AnyRef<'_>

impl EncodeValue for DateTime

impl<'a> EncodeValue for Ia5StringRef<'a>

impl<'a> EncodeValue for PrintableStringRef<'a>

impl<'a> EncodeValue for TeletexStringRef<'a>

impl<'a> EncodeValue for Utf8StringRef<'a>

impl<'a> EncodeValue for VideotexStringRef<'a>

impl<'a, Params, Key> EncodeValue for SubjectPublicKeyInfo<Params, Key>

where Params: Choice<'a, Error = Error> + Encode, Key: Encode,

impl<'a, Params, Key, PubKey> EncodeValue for PrivateKeyInfo<Params, Key, PubKey>

where Params: Choice<'a, Error = Error> + Encode, Key: EncodeValue + FixedTag, PubKey: BitStringLike,

impl<Params> EncodeValue for AlgorithmIdentifier<Params>

where Params: Encode,

impl<T> EncodeValue for Application<T>

where T: EncodeValue + Tagged,

impl<T> EncodeValue for ApplicationRef<'_, T>

where T: EncodeValue + Tagged,

impl<T> EncodeValue for ContextSpecific<T>

where T: EncodeValue + Tagged,

impl<T> EncodeValue for ContextSpecificRef<'_, T>

where T: EncodeValue + Tagged,

impl<T> EncodeValue for Private<T>

where T: EncodeValue + Tagged,

impl<T> EncodeValue for PrivateRef<'_, T>

where T: EncodeValue + Tagged,

impl<T> EncodeValue for SetOfVec<T>

where T: Encode + DerOrd,

Available on crate feature alloc only.

impl<T> EncodeValue for EncodeValueRef<'_, T>

where T: EncodeValue,

impl<const MAX_SIZE: usize> EncodeValue for ObjectIdentifier<MAX_SIZE>