CkoDkim Objective-C Reference Documentation

CkoDkim

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.)

Properties

@property (nonatomic) BOOL AbortCurrent;

Introduced in version 9.5.0.58

When set to YES, 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 NO when the next method is called. When the abort occurs, this property is reset to NO. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

@property (nonatomic, copy) NSString *DebugLogFilePath;

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.

@property (nonatomic, copy) NSString *DkimAlg;

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".

@property (nonatomic, copy) NSNumber *DkimBodyLengthCount;

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.

@property (nonatomic, copy) NSString *DkimCanon;

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".

@property (nonatomic, copy) NSString *DkimDomain;

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

@property (nonatomic, copy) NSString *DkimHeaders;

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".

@property (nonatomic, copy) NSString *DkimSelector;

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".

@property (nonatomic, copy) NSString *DomainKeyAlg;

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

@property (nonatomic, copy) NSString *DomainKeyCanon;

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

@property (nonatomic, copy) NSString *DomainKeyDomain;

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

@property (nonatomic, copy) NSString *DomainKeyHeaders;

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".

@property (nonatomic, copy) NSString *DomainKeySelector;

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".

@property (nonatomic, copy) NSNumber *HeartbeatMs;

The number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any method call prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.

@property (nonatomic, readonly, copy) NSString *LastErrorHtml;

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.

@property (nonatomic, readonly, copy) NSString *LastErrorText;

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.

Concept of LastErrorText

LastErrorText Standard Information

@property (nonatomic, readonly, copy) NSString *LastErrorXml;

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.

@property (nonatomic) BOOL LastMethodSuccess;

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of YES indicates success, a value of NO 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 = YES and failure = NO.
  • 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 YES. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

@property (nonatomic) BOOL VerboseLogging;

If set to YES, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is NO. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

@property (nonatomic, readonly, copy) NSString *Version;

Version of the component/library, such as "9.5.0.63"

Methods

- (NSData *)AddDkimSignature:(NSData *)mimeIn;

This method is deprecated. It will be removed in a future version.

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

Note: This method is deprecated. Use the DkimSign method instead.

Returns nil on failure

Add DKIM-Signature Header to MIME / Email

Send DKIM Signed Email

- (NSData *)AddDomainKeySignature:(NSData *)mimeIn;

This method is deprecated. It will be removed in a future version.

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

Note: This method is deprecated. Use the DomainKeySign method instead.

Returns nil on failure

Add DomainKey-Signature Header to MIME / Email

- (BOOL)DkimSign:(CkoBinData *)mimeData;

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 YES for success, NO for failure.

- (BOOL)DkimVerify:(NSNumber *)sigIndex
    mimeData:(CkoBinData *)mimeData;

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.

Important: Many anti-virus programs, such as AVG, will modify the MIME of an email as it is received. This will cause DKIM signature verification to fail because the body of the MIME is modified.

Returns YES for success, NO for failure.

- (BOOL)DomainKeySign:(CkoBinData *)mimeData;

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 YES for success, NO for failure.

- (BOOL)DomainKeyVerify:(NSNumber *)sigIndex
    mimeData:(CkoBinData *)mimeData;

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.

Important: Many anti-virus programs, such as AVG, will modify the MIME of an email as it is received. This will cause DomainKey signature verification to fail because the body of the MIME is modified.

Returns YES for success, NO for failure.

- (BOOL)LoadDkimPk:(NSString *)privateKey
    optionalPassword:(NSString *)optionalPassword;

This method is deprecated. It will be removed in a future version.

Loads an RSA private key to be used for creating a DKIM-Signature. Any valid RSA private key format that is not binary, such as PEM or XML, may be passed to this method. This method will automatically determine the format and parse it correctly. A password is only required if key is encrypted, such as for encrypted PEM.

Note: This method is deprecated. Use the SetDkimPrivateKey method instead.

Returns YES for success, NO for failure.

DKIM Signature using Windows Current User Certificate Store

- (BOOL)LoadDkimPkBytes:(NSData *)privateKeyDer
    optionalPassword:(NSString *)optionalPassword;

This method is deprecated. It will be removed in a future version.

Loads an RSA private key to be used for creating a DKIM-Signature. Any valid RSA private key binary format, such as DER, may be passed to this method. This method will automatically determine the format and parse it correctly. A password is only required if key is encrypted.

Note: This method is deprecated. Use the SetDkimPrivateKey method instead.

Returns YES for success, NO for failure.

- (BOOL)LoadDkimPkFile:(NSString *)privateKeyFilepath
    optionalPassword:(NSString *)optionalPassword;

This method is deprecated. It will be removed in a future version.

Loads an RSA private key file to be used for creating a DKIM-Signature. The file name contains any valid RSA private key format, such as DER, PKCS8, PEM, XML, etc. This method will automatically determine the format and parse it correctly. A password is only required if key is encrypted, such as for encrypted PEM or encrypted PKCS8.

Note: This method is deprecated. Use the SetDkimPrivateKey method instead.

Returns YES for success, NO for failure.

- (BOOL)LoadDomainKeyPk:(NSString *)privateKey
    optionalPassword:(NSString *)optionalPassword;

This method is deprecated. It will be removed in a future version.

Loads an RSA private key to be used for creating a DomainKey-Signature. Any valid RSA private key format that is not binary, such as PEM or XML, may be passed to this method. This method will automatically determine the format and parse it correctly. A password is only required if key is encrypted, such as for encrypted PEM.

Note: This method is deprecated. Use the SetDomainKeyPrivateKey method instead.

Returns YES for success, NO for failure.

- (BOOL)LoadDomainKeyPkBytes:(NSData *)privateKeyDer
    optionalPassword:(NSString *)optionalPassword;

This method is deprecated. It will be removed in a future version.

Loads an RSA private key to be used for creating a DomainKey-Signature. Any valid RSA private key binary format, such as DER, may be passed to this method. This method will automatically determine the format and parse it correctly. A password is only required if key is encrypted.

Note: This method is deprecated. Use the SetDomainKeyPrivateKey method instead.

Returns YES for success, NO for failure.

- (BOOL)LoadDomainKeyPkFile:(NSString *)privateKeyFilepath
    optionalPassword:(NSString *)optionalPassword;

This method is deprecated. It will be removed in a future version.

Loads an RSA private key file to be used for creating a DomainKey-Signature. The file name contains any valid RSA private key format, such as DER, PKCS8, PEM, XML, etc. This method will automatically determine the format and parse it correctly. A password is only required if key is encrypted, such as for encrypted PEM or encrypted PKCS8.

Note: This method is deprecated. Use the SetDomainKeyPrivateKey method instead.

Returns YES for success, NO for failure.

- (BOOL)LoadPublicKey:(NSString *)selector
    domain:(NSString *)domain
    publicKey:(NSString *)publicKey;

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 YES for success, NO for failure.

- (BOOL)LoadPublicKeyFile:(NSString *)selector
    domain:(NSString *)domain
    publicKeyFilepath:(NSString *)publicKeyFilepath;

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 YES for success, NO for failure.

- (NSNumber *)NumDkimSignatures:(NSData *)mimeData;

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

- (NSNumber *)NumDomainKeySignatures:(NSData *)mimeData;

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

- (BOOL)PrefetchPublicKey:(NSString *)selector
    domain:(NSString *)domain;

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 YES for success, NO for failure.

- (CkoTask *)PrefetchPublicKeyAsync:(NSString *)selector
    domain:(NSString *)domain;

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

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

- (BOOL)SaveLastError:(NSString *)path;

Saves the last-error information (the contents of LastErrorXml) to an XML formatted file.

Returns YES for success, NO for failure.

- (BOOL)SetDkimPrivateKey:(CkoPrivateKey *)privateKey;

Introduced in version 9.5.0.71

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

Returns YES for success, NO for failure.

- (BOOL)SetDomainKeyPrivateKey:(CkoPrivateKey *)privateKey;

Introduced in version 9.5.0.71

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

Returns YES for success, NO for failure.

- (BOOL)UnlockComponent:(NSString *)unlockCode;

Unlocks the component allowing for the full functionality to be used. If this method unexpectedly returns NO, examine the contents of the LastErrorText property to determine the reason for failure.

Returns YES for success, NO for failure.

Diagnosing UnlockComponent Problems

UnlockComponent LastErrorText shows exact string passed to it.

Verify UnlockComponent Success w/ Purchased Unlock Code

LastErrorText Standard Information

- (BOOL)VerifyDkimSignature:(NSNumber *)sigIdx
    mimeData:(NSData *)mimeData;

This method is deprecated. It will be removed in a future version.

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

Important: Many anti-virus programs, such as AVG, will modify the MIME of an email as it is received. This will cause DKIM signature verification to fail because the body of the MIME is modified.

Note: This method is deprecated. Use the DkimVerify method instead.

Returns YES for success, NO for failure.

- (CkoTask *)VerifyDkimSignatureAsync:(NSNumber *)sigIdx
    mimeData:(NSData *)mimeData;

This method is deprecated. It will be removed in a future version.

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

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

- (BOOL)VerifyDomainKeySignature:(NSNumber *)sigIdx
    mimeData:(NSData *)mimeData;

This method is deprecated. It will be removed in a future version.

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

Important: Many anti-virus programs, such as AVG, will modify the MIME of an email as it is received. This will cause DomainKey signature verification to fail because the body of the MIME is modified.

Note: This method is deprecated. Use the DomainKeyVerify method instead.

Returns YES for success, NO for failure.

- (CkoTask *)VerifyDomainKeySignatureAsync:(NSNumber *)sigIdx
    mimeData:(NSData *)mimeData;

This method is deprecated. It will be removed in a future version.

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

Note: Async method event callbacks happen in the background thread. Accessing and updating UI elements existing in the main thread may require special considerations.

Returns nil on failure

How to Run an Asynchronous Task

Events

To implement an event callback, your application would define and implement a class that inherits from CkoBaseProgress. Your application can implement methods to override some or all of the default/empty method implementations of the CkoBaseProgress base class.

For example:

  CkoDkim *dkim = [[CkoDkim alloc] init];

  MyDkimProgress *callbackObj = [[MyDkimProgress alloc] init];

  [dkim setEventCallbackObject:callbackObj];

MyDkimProgress interface example:

#import "CkoDkimProgress.h"

@interface MyDkimProgress : CkoBaseProgress {

}

    - (id)init;
    - (void)dealloc;
    - (void)dispose;

    - (void)AbortCheck:(BOOL *)abort;

    - (void)BinaryData:(NSData *)data 
        length:(NSNumber *)length;

    - (void)PercentDone:(NSNumber *)pctDone 
        abort:(BOOL *)abort;

    - (void)ProgressInfo:(NSString *)name 
        value:(NSString *)value;

    - (void)TaskCompleted:(CkoTask *)task;

    - (void)TextData:(NSString *)data;

@end

- (void)AbortCheck:(BOOL *)abort;

Provides the opportunity for a method call to be aborted. The AbortCheck event is fired periodically based on the value of the HeartbeatMs property. If HeartbeatMs is 0, then no AbortCheck events will fire. As an example, to fire 5 AbortCheck events per second, set the HeartbeatMs property equal to 200.

- (void)BinaryData:(NSData *)data
    length:(NSNumber *)length;

Binary data provided by certain methods.

- (void)PercentDone:(NSNumber *)pctDone
    abort:(BOOL *)abort;

Provides the percentage completed for any method that involves network communications or time-consuming processing (assuming it is a method where a percentage completion can be measured). This event is only fired when it is possible to know a percentage completion, and when it makes sense to express the operation as a percentage completed. The pctDone argument will have a value from 1 to 100. For operations (Chilkat method calls) that complete very quickly, the number of PercentDone callbacks will vary, but the final callback should have a value of 100. For long running operations, no more than one callback per percentage point will occur (for example: 1, 2, 3, ... 98, 99, 100).

The PercentDone callback counts as an AbortCheck event. For method calls that complete quickly such that PercentDone events fire, it may be that AbortCheck events don't fire because the opportunity to abort is already provided in the PercentDone callback. For time consuming operations, where the amount of time between PercentDone callbacks are long, AbortCheck callbacks may be used to allow for the operation to be aborted in a more responsive manner.

The abort output argument provides a means for aborting the operation. Setting it to YES will cause the method to abort and return a failed status (or whatever return value indicates failure).

- (void)ProgressInfo:(NSString *)name
    value:(NSString *)value;

A general name/value event that provides information about what is happening during a method call. To find out what information is available, write code to handle this event and log the name/value pairs. Most are self-explanatory.

- (void)TaskCompleted:(CkoTask *)task;

Called in the background thread when an asynchronous task completes.

- (void)TextData:(NSString *)data;

Text data provided by certain methods.