Dkim Lianja Reference Documentation

Dkim

Current Version: 10.0.0

DomainKeys API for creating and verifying DKIM-Signature and DomainKey-Signature MIME (email) header fields. This API is included with the "Chilkat MIME" license. ("Chilkat MIME" may be referred to as "Chilkat S/MIME" on some chilkatsoft.com web pages. They are the same product.)

Object Creation

loObject = createobject("CkDkim")

Properties

AbortCurrent
AbortCurrent As Boolean
Introduced in version 9.5.0.58

When set to .T., causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to .F. when the next method is called. When the abort occurs, this property is reset to .F.. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

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DebugLogFilePath
DebugLogFilePath As Character

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

  1. a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
  2. the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
  3. there is an internal problem (bug) in the Chilkat code that causes the hang.

More Information and Examples
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DkimAlg
DkimAlg As Character

The signing algorithm to be used in creating the DKIM-Signature. Possible values are "rsa-sha256" and "rsa-sha1". The default value is "rsa-sha256".

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DkimBodyLengthCount
DkimBodyLengthCount As Numeric

Optional body length count to set a maximum number of body bytes to be hashed when creating the DKIM-Signature field. The default value is 0, indicating that the entire body should be hashed.

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DkimCanon
DkimCanon As Character

Canonicalization algorithm to be used for both header and body when creating the DKIM-Signature. Possible values are "simple" and "relaxed". The default value is "relaxed".

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DkimDomain
DkimDomain As Character

The domain name of the signing domain when creating the DKIM-Signature.

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DkimHeaders
DkimHeaders As Character

A colon-separated list of header field names that identify headers presented to the signing algorithm when creating the DKIM-Signature. The default value is: "mime-version:date:message-id:subject:from:to:content-type".

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DkimSelector
DkimSelector As Character

The selector to be used to form the DNS query for the public key. This property applies to creating a DKIM-Signature. For example, if the selector is "reykjavik" and the domain is "example-code.com", then the DNS query would be for "reykjavik._domainkey.example-code.com".

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DomainKeyAlg
DomainKeyAlg As Character

The signing algorithm to be used in creating the DomainKey-Signature. The only possible value is "rsa-sha1". The default value is "rsa-sha1".

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DomainKeyCanon
DomainKeyCanon As Character

Canonicalization algorithm to be used for when creating the DomainKey-Signature. Possible values are "simple" and "nofws". The default value is "nofws".

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DomainKeyDomain
DomainKeyDomain As Character

The domain name of the signing domain when creating the DomainKey-Signature.

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DomainKeyHeaders
DomainKeyHeaders As Character

A colon-separated list of header field names that identify headers presented to the signing algorithm when creating the DomainKey-Signature. The default value is: "mime-version:date:message-id:subject:from:to:content-type".

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DomainKeySelector
DomainKeySelector As Character

The selector to be used to form the DNS query for the public key. This property applies to creating a DomainKey-Signature. For example, if the selector is "reykjavik" and the domain is "example-code.com", then the DNS query would be for "reykjavik._domainkey.example-code.com".

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LastErrorHtml
LastErrorHtml As Character (read-only)

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

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LastErrorText
LastErrorText As Character (read-only)

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

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LastErrorXml
LastErrorXml As Character (read-only)

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

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LastMethodSuccess
LastMethodSuccess As Boolean

Indicate whether the last method call succeeded or failed. A value of .T. indicates success, a value of .F. indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

  • Any method that returns a string.
  • Any method returning a Chilkat object, binary bytes, or a date/time.
  • Any method returning a standard boolean status value where success = .T. and failure = .F..
  • Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to .T.. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

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VerboseLogging
VerboseLogging As Boolean

If set to .T., then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is .F.. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

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VerifyInfo
VerifyInfo As Character (read-only)
Introduced in version 9.5.0.76

Contains JSON with information about the last DKIM or DomainKey signature verified (or verification failure). The JSON will contain information like this:

{
  "domain": "amazonses.com",
  "selector": "7v7vs6w47njt4pimodk5mmttbegzsi6n",
  "publicKey": "MIGfMA0GCSq...z6uqeQIDAQAB",
  "canonicalization": "relaxed/simple",
  "algorithm": "rsa-sha256",
  "signedHeaders": "Subject:From:To:Date:Mime-Version:Content-Type:References:Message-Id:Feedback-ID",
  "verified": "yes"
}

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Version
Version As Character (read-only)

Version of the component/library, such as "9.5.0.94"

More Information and Examples
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Methods

DkimSign
DkimSign(mimeData As CkBinData) As Boolean
Introduced in version 9.5.0.71

Constructs and prepends a DKIM-Signature header to the MIME passed in mimeData. Prior to calling this method, your program must set both the DkimDomain and DkimSelector properties, and it must load a private key by calling SetDkimPrivateKey.

Returns .T. for success, .F. for failure.

More Information and Examples
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DkimVerify
DkimVerify(sigIndex As Numeric, mimeData As CkBinData) As Boolean
Introduced in version 9.5.0.71

Verifies the Nth DKIM-Signature header in the mimeData. (In most cases, there is only one signature.) The 1st signature is at sigIndex 0.

On return, the VerifyInfo property will contain additional information about the DKIM-Signature that was verified (or not verified).

Returns .T. for success, .F. for failure.

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DomainKeySign
DomainKeySign(mimeData As CkBinData) As Boolean
Introduced in version 9.5.0.71

Constructs and prepends a DomainKey-Signature header to the MIME passed in mimeData. Prior to calling this method, your program must set both the DomainKeyDomain and DomainKeySelector properties, and it must load a private key by calling SetDomainKeyPrivateKey.

Returns .T. for success, .F. for failure.

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DomainKeyVerify
DomainKeyVerify(sigIndex As Numeric, mimeData As CkBinData) As Boolean
Introduced in version 9.5.0.71

Verifies the Nth DomainKey-Signature header in the mimeData. (In most cases, there is only one signature.) The 1st signature is at sigIndex 0.

On return, the VerifyInfo property will contain additional information about the DKIM-Signature that was verified (or not verified).

Returns .T. for success, .F. for failure.

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LoadPublicKey
LoadPublicKey(selector As Character, domain As Character, publicKey As Character) As Boolean

Caches a public key to be used for verifying DKIM and DomainKey signatures for a given selector and domain. The publicKey is a string containing an RSA public key in any text format, such as XML, PEM, etc. This method will automatically detect the format and load the public key correctly. This method is useful for testing DKIM and DomainKey verification when your public key has not yet been installed in DNS.

Returns .T. for success, .F. for failure.

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LoadPublicKeyFile
LoadPublicKeyFile(selector As Character, domain As Character, publicKeyFilepath As Character) As Boolean

Caches a public key to be used for verifying DKIM and DomainKey signatures for a given selector and domain. The publicKeyFilepath is a filepath of an RSA public key in any format. This method will automatically detect the format and load the public key correctly. This method is useful for testing DKIM and DomainKey verification when your public key has not yet been installed in DNS.

Returns .T. for success, .F. for failure.

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LoadTaskCaller
LoadTaskCaller(task As CkTask) As Boolean
Introduced in version 9.5.0.80

Loads the caller of the task's async method.

Returns .T. for success, .F. for failure.

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NumDkimSigs
NumDkimSigs(mimeData As CkBinData) As Numeric
Introduced in version 9.5.0.76

Returns the number of DKIM-Signature header fields found in mimeData.

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NumDomainKeySigs
NumDomainKeySigs(mimeData As CkBinData) As Numeric
Introduced in version 9.5.0.76

Returns the number of DomainKey-Signature header fields found in mimeData.

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PrefetchPublicKey
PrefetchPublicKey(selector As Character, domain As Character) As Boolean

Useful if your application is going to verify many emails from a single domain (or a few domains). This eliminates the need to do a DNS lookup to fetch the public key each time an email's DKIM or DomainKey signature is verified.

This method may be called multiple times -- once for each selector/domain to be pre-fetched. The verify methods (VerifyDkimSignature and VerifyDomainKeySignature) will use a pre-fetched key if the selector and domain match.

Returns .T. for success, .F. for failure.

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PrefetchPublicKeyAsync (1)
PrefetchPublicKeyAsync(selector As Character, domain As Character) As CkTask

Creates an asynchronous task to call the PrefetchPublicKey method with the arguments provided. (Async methods are available starting in Chilkat v9.5.0.52.)

Returns .F. on failure

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SetDkimPrivateKey
SetDkimPrivateKey(privateKey As CkPrivateKey) As Boolean
Introduced in version 9.5.0.71

Sets the private key file to be used for creating a DKIM-Signature.

Returns .T. for success, .F. for failure.

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SetDomainKeyPrivateKey
SetDomainKeyPrivateKey(privateKey As CkPrivateKey) As Boolean
Introduced in version 9.5.0.71

Sets the private key file to be used for creating a DomainKey-Signature.

Returns .T. for success, .F. for failure.

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