Class DkimSignatureHeader

A parsed DKIM-Signature header (RFC 6376 §3.5). The header value is a semicolon-separated list of tag=value pairs. Tags are short alphanumeric strings. Whitespace is allowed around semicolons and equals signs.

Inheritance

object

DkimSignatureHeader

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

object.GetType()

Namespace: DRIT.Mail.Rfc.Dkim

Assembly: DRIT.Mail.dll

Syntax

public sealed class DkimSignatureHeader

Constructors

DkimSignatureHeader(int, DkimSigningAlgorithm, string?, string?, DkimCanonicalizationMode, DkimCanonicalizationMode, string, IReadOnlyList<string>, string?, long?, string, string, DateTimeOffset?, DateTimeOffset?, IReadOnlyList<string>)

Initializes a new instance of the DkimSignatureHeader class with the specified tag values.

Declaration

public DkimSignatureHeader(int version, DkimSigningAlgorithm algorithm, string? signature, string? bodyHash, DkimCanonicalizationMode headerCanonicalization, DkimCanonicalizationMode bodyCanonicalization, string domain, IReadOnlyList<string> signedHeaders, string? identity, long? bodyLength, string queryMethod, string selector, DateTimeOffset? timestamp, DateTimeOffset? expiration, IReadOnlyList<string> copiedHeaders)

Parameters

Type	Name	Description
int	version
DkimSigningAlgorithm	algorithm
string	signature
string	bodyHash
DkimCanonicalizationMode	headerCanonicalization
DkimCanonicalizationMode	bodyCanonicalization
string	domain
IReadOnlyList<string>	signedHeaders
string	identity
long?	bodyLength
string	queryMethod
string	selector
DateTimeOffset?	timestamp
DateTimeOffset?	expiration
IReadOnlyList<string>	copiedHeaders

Properties

Algorithm

Gets the signing algorithm (a=).

Declaration

public DkimSigningAlgorithm Algorithm { get; }

Property Value

Type	Description
DkimSigningAlgorithm

BodyCanonicalization

Gets the body canonicalization mode (c=, second part).

Declaration

public DkimCanonicalizationMode BodyCanonicalization { get; }

Property Value

Type	Description
DkimCanonicalizationMode

BodyHash

Gets the body hash (bh=, base64), or null if absent.

Declaration

public string? BodyHash { get; }

Property Value

Type	Description
string

BodyLength

Gets the body length count (l=), or null if not present.

Declaration

public long? BodyLength { get; }

Property Value

Type	Description
long?

CopiedHeaders

Gets the copied header fields (z=), pipe-separated list, or empty if absent.

Declaration

public IReadOnlyList<string> CopiedHeaders { get; }

Property Value

Type	Description
IReadOnlyList<string>

Domain

Gets the signing domain (d=).

Declaration

public string Domain { get; }

Property Value

Type	Description
string

Expiration

Gets the signature expiration (x=), or null if absent.

Declaration

public DateTimeOffset? Expiration { get; }

Property Value

Type	Description
DateTimeOffset?

HeaderCanonicalization

Gets the header canonicalization mode (c=, first part).

Declaration

public DkimCanonicalizationMode HeaderCanonicalization { get; }

Property Value

Type	Description
DkimCanonicalizationMode

Identity

Gets the signer identity (i=), or null if absent.

Declaration

public string? Identity { get; }

Property Value

Type	Description
string

QueryMethod

Gets the query method (q=). Defaults to "dns/txt".

Declaration

public string QueryMethod { get; }

Property Value

Type	Description
string

Selector

Gets the selector (s=).

Declaration

public string Selector { get; }

Property Value

Type	Description
string

Signature

Gets the signature data (b=, base64), or null if absent.

Declaration

public string? Signature { get; }

Property Value

Type	Description
string

SignedHeaders

Gets the signed header fields (h=), colon-separated list.

Declaration

public IReadOnlyList<string> SignedHeaders { get; }

Property Value

Type	Description
IReadOnlyList<string>

Timestamp

Gets the signature timestamp (t=), or null if absent.

Declaration

public DateTimeOffset? Timestamp { get; }

Property Value

Type	Description
DateTimeOffset?

Version

Gets the version tag (v=). MUST be 1.

Declaration

public int Version { get; }

Property Value

Type	Description
int

Methods

Parse(string)

Parses a DKIM-Signature header value (the part after "DKIM-Signature:").

Declaration

public static DkimSignatureHeader Parse(string headerValue)

Parameters

Type	Name	Description
string	headerValue	The header value, possibly folded.

Returns

Type	Description
DkimSignatureHeader	The parsed DkimSignatureHeader.

Exceptions

Type	Condition
DkimException	Thrown if the header is malformed or a required tag is missing.

ToString()

Serializes this header back to tag-value form (unfolded, single line, without the "DKIM-Signature:" prefix). Tags are emitted in a conventional order. The b= tag is included only if Signature is non-null.

Declaration

public override string ToString()

Returns

Type	Description
string

Overrides

object.ToString()

ToString(bool)

Serializes this header to tag-value form. When includeSignature is false, the b= tag is emitted with an empty value (used during signing and verification).

Declaration

public string ToString(bool includeSignature)

Parameters

Type	Name	Description
bool	includeSignature	The include signature used by the operation.

Returns

Type	Description
string