Enum der::Tag

source · [−]

#[non_exhaustive]
pub enum Tag {
Show 21 variants    Boolean,
    Integer,
    BitString,
    OctetString,
    Null,
    ObjectIdentifier,
    Real,
    Enumerated,
    Utf8String,
    Sequence,
    Set,
    NumericString,
    PrintableString,
    Ia5String,
    UtcTime,
    GeneralizedTime,
    VisibleString,
    BmpString,
    Application {
        constructed: bool,
        number: TagNumber,
    },
    ContextSpecific {
        constructed: bool,
        number: TagNumber,
    },
    Private {
        constructed: bool,
        number: TagNumber,
    },
}

Expand description

ASN.1 tags.

Tags are the leading identifier octet of the Tag-Length-Value encoding used by ASN.1 DER and identify the type of the subsequent value.

They are described in X.690 Section 8.1.2: Identifier octets, and structured as follows:

| Class | P/C | Tag Number |

Bits 8/7: Class
Bit 6: primitive (0) or constructed (1)
Bits 5-1: tag number

Variants (Non-exhaustive)

This enum is marked as non-exhaustive

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

`Boolean`

BOOLEAN tag: 1.

`Integer`

INTEGER tag: 2.

`BitString`

BIT STRING tag: 3.

`OctetString`

OCTET STRING tag: 4.

`Null`

NULL tag: 5.

`ObjectIdentifier`

OBJECT IDENTIFIER tag: 6.

`Real`

REAL tag: 9.

`Enumerated`

ENUMERATED tag: 10.

`Utf8String`

UTF8String tag: 12.

`Sequence`

SEQUENCE tag: 16.

`Set`

SET and SET OF tag: 17.

`NumericString`

NumericString tag: 18.

`PrintableString`

PrintableString tag: 19.

`Ia5String`

IA5String tag: 22.

`UtcTime`

UTCTime tag: 23.

`GeneralizedTime`

GeneralizedTime tag: 24.

`VisibleString`

VisibleString tag: 26.

`BmpString`

BMPString tag: 30.

`Application`

Fields

constructed: bool

Is this tag constructed? (vs primitive).

number: TagNumber

Tag number.

Application tag.

`ContextSpecific`

Fields

constructed: bool

Is this tag constructed? (vs primitive).

number: TagNumber

Tag number.

Context-specific tag.

`Private`

Fields

constructed: bool

Is this tag constructed? (vs primitive).

number: TagNumber

Tag number.

Private tag number.

Implementations

impl Tag

pub fn assert_eq(self, expected: Tag) -> Result<Tag>

Assert that this Tag matches the provided expected tag.

On mismatch, returns an Error with ErrorKind::TagUnexpected.

pub fn class(self) -> Class

Get the Class that corresponds to this Tag.

pub fn number(self) -> TagNumber

Get the TagNumber (lower 6-bits) for this tag.

pub fn is_constructed(self) -> bool

Does this tag represent a constructed (as opposed to primitive) field?

pub fn is_application(self) -> bool

Is this an application tag?

pub fn is_context_specific(self) -> bool

Is this a context-specific tag?

pub fn is_private(self) -> bool

Is this a private tag?

pub fn is_universal(self) -> bool

Is this a universal tag?

pub fn octet(self) -> u8

Get the octet encoding for this Tag.

pub fn length_error(self) -> Error

Create an Error for an invalid Length.

pub fn non_canonical_error(self) -> Error

Create an Error for an non-canonical value with the ASN.1 type identified by this tag.

pub fn unexpected_error(self, expected: Option<Self>) -> Error

Create an Error because the current tag was unexpected, with an optional expected tag.

pub fn value_error(self) -> Error

Create an Error for an invalid value with the ASN.1 type identified by this tag.

Trait Implementations

impl Clone for Tag

fn clone(&self) -> Tag

Returns a copy of the value. Read more

1.0.0 · source

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

Performs copy-assignment from source. Read more

impl Debug for Tag

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

Formats the value using the given formatter. Read more

impl<'a> Decode<'a> for Tag

fn decode<R: Reader<'a>>(reader: &mut R) -> Result<Self>

Attempt to decode this message using the provided decoder.

fn from_der(bytes: &'a [u8 ]) -> Result<Self>

Parse Self from the provided DER-encoded byte slice.

impl DerOrd for Tag

fn der_cmp(&self, other: &Self) -> Result<Ordering>

Return an Ordering between self and other when serialized as ASN.1 DER. Read more

impl Display for Tag

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

Formats the value using the given formatter. Read more

impl Encode for Tag

fn encoded_len(&self) -> Result<Length>

Compute the length of this value in bytes when encoded as ASN.1 DER.

fn encode(&self, writer: &mut dyn Writer) -> Result<()>

Encode this value as ASN.1 DER using the provided Encoder.

fn encode_to_slice<'a>(&self, buf: &'a mut [u8 ]) -> Result<&'a [u8 ]>

Encode this value to the provided byte slice, returning a sub-slice containing the encoded message. Read more

fn encode_to_vec(&self, buf: &mut Vec<u8>) -> Result<Length>

Available on crate feature alloc only.

Encode this message as ASN.1 DER, appending it to the provided byte vector. Read more

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

Available on crate feature alloc only.

Serialize this message as a byte vector.

impl From<&'_ Tag> for u8

fn from(tag: &Tag) -> u8

Converts to this type from the input type.

impl From<Tag> for u8

fn from(tag: Tag) -> u8

Converts to this type from the input type.

impl Ord for Tag

fn cmp(&self, other: &Tag) -> Ordering

This method returns an Ordering between self and other. Read more

1.21.0 · source

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values. Read more

1.21.0 · source

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values. Read more

1.50.0 · source

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval. Read more

impl PartialEq<Tag> for Tag

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

This method tests for self and other values to be equal, and is used by ==. Read more

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

This method tests for !=.

impl PartialOrd<Tag> for Tag

fn partial_cmp(&self, other: &Tag) -> Option<Ordering>

This method returns an ordering between self and other values if one exists. Read more

1.0.0 · source

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

This method tests less than (for self and other) and is used by the < operator. Read more

1.0.0 · source

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

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more

1.0.0 · source

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

This method tests greater than (for self and other) and is used by the > operator. Read more

1.0.0 · source

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

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

impl TryFrom<u8> for Tag

type Error = Error

The type returned in the event of a conversion error.

fn try_from(byte: u8) -> Result<Tag>

Performs the conversion.

impl Copy for Tag

impl Eq for Tag

impl StructuralEq for Tag

impl StructuralPartialEq for Tag

Auto Trait Implementations

impl RefUnwindSafe for Tag

impl Send for Tag

impl Sync for Tag

impl Unpin for Tag

impl UnwindSafe for Tag

Blanket Implementations

impl<T> Any for T where
T: 'static + ?Sized,

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more

impl<T> Borrow<T> for T where
T: ?Sized,

const: unstable · source

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for T where
T: ?Sized,

const: unstable · source

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more

impl<T> From<T> for T

const: unstable · source

fn from(t: T) -> T

Returns the argument unchanged.

impl<T, U> Into<U> for T where
U: From<T>,

const: unstable · source

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

impl<T> ToOwned for T where
T: Clone,

type Owned = T

The resulting type after obtaining ownership.

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more

fn clone_into(&self, target: &mut T)

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

impl<T> ToString for T where
T: Display + ?Sized,

default fn to_string(&self) -> String

Converts the given value to a String. Read more

impl<T, U> TryFrom<U> for T where
U: Into<T>,

type Error = Infallible

The type returned in the event of a conversion error.

const: unstable · source

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.

impl<T, U> TryInto<U> for T where
U: TryFrom<T>,

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.

const: unstable · source

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.