Foxit PDF SDK
<FSSignatureCallback> Protocol Reference

Inherits <NSObject>.

Instance Methods

(FSProgressiveState- continueCalcDigest:client_data:
 A callback function used to continue the custom digest calculation process. More...
 
(NSData *) - getDigest:
 A callback function used to get the digest after the calculation process is finished. More...
 
(BOOL) - isNeedPadData
 Whether return all contents all hex string include padding zero when call Verify function. More...
 
(NSData *) - sign:cert_path:cert_password:digest_algorithm:client_data:
 A callback function used to do signing and return the signed data. More...
 
(BOOL) - startCalcDigest:byte_range_array:signature:client_data:
 A callback function used to start a custom digest calculation, mainly to initialize the calculation process. More...
 
(FSSignatureStates- verifySigState:signed_data:client_data:
 A callback function used to do verifying and return the verify state. More...
 

Detailed Description

This class represent a callback object to sign or verify signature. All the pure virtual functions in this class are used as callback functions and should be implemented by user, in order to sign or verify signature in a customized way.
User can set register customized signature callback object to Foxit PDF SDK by function FSLibrary::registerSignatureCallback:sub_filter:signature_callback: with filter and sub filter as the callback name.

See also
FSLibrary

Method Documentation

◆ continueCalcDigest:client_data:()

- (FSProgressiveState) continueCalcDigest: (id< FSPauseCallback >)  pause
client_data: (void *)  client_data 
required

A callback function used to continue the custom digest calculation process.

Parameters
[in]pausePause object which decides if the calculation process needs to be paused. If this is nil, it means not to pause during the calculation process. If this is not nil, please check the returned value of function PauseCallback::NeedToPauseNow and decide when to pause the calculation process.
[in]client_dataPointer to a user-defined object, which is passed by user from function FSSignature::startSign:cert_password:digest_algorithm:save_path:client_data:pause: or FSSignature::startVerify:pause:.
Returns
FSProgressiveFinished means the rendering is finished successfully.
FSProgressiveToBeContinued means the calculation process is not finished yet and callback function FSSignatureCallback::continueCalcDigest:client_data: would be triggered again to continue the process.
FSProgressiveError means any error occurs.

◆ getDigest:()

- (NSData *) getDigest: (void *)  client_data
required

A callback function used to get the digest after the calculation process is finished.

This callback function will be triggered when the calculation process is finished successfully.

Parameters
[in]client_dataPointer to a user-defined object, which is passed by user from function FSSignature::startSign:cert_password:digest_algorithm:save_path:client_data:pause: or FSSignature::startVerify:pause:.
Returns
The digest string. If there is any error, please return an empty string.

◆ isNeedPadData()

- (BOOL) isNeedPadData
required

Whether return all contents all hex string include padding zero when call Verify function.

Returns
YES means to return all data in contents steam, while NO means to return contents data without zero in stream end.

◆ sign:cert_path:cert_password:digest_algorithm:client_data:()

- (NSData *) sign: (NSData *)  digest
cert_path: (NSString *)  cert_path
cert_password: (NSString *)  cert_password
digest_algorithm: (FSSignatureDigestAlgorithm digest_algorithm
client_data: (void *)  client_data 
required

A callback function used to do signing and return the signed data.

Host application provides this callback function for custom sign mechanism. This callback function would be triggered during the signature signing process.

Parameters
[in]digestThe digest data buffer, for source file buffer to be signed.
[in]cert_pathThe certificate file path, which will be used for signing.
[in]cert_passwordThe password string, used to open the cert file. If this is an empty string, that means no password is required.
[in]digest_algorithmThe algorithm of message digest for signed data. Please refer to values starting from FSSignatureDigestSHA1 and this would be one of these values.
[in]client_dataPointer to a user-defined object, which is passed by user from function FSSignature::startSign:cert_password:digest_algorithm:save_path:client_data:pause: or FSSignature::startVerify:pause:.
Returns
Signed data. If there is any error, please return an empty string.
The length of returned signed data should be within the default length of signature contents which is 7942 by default or specified by fucntion FSSignature::setDefaultContentsLength: before signing the unsigned signature.

◆ startCalcDigest:byte_range_array:signature:client_data:()

- (BOOL) startCalcDigest: (id< FSFileReaderCallback >)  file
byte_range_array: (NSArray< NSNumber * > *)  byte_range_array
signature: (FSSignature *)  signature
client_data: (void *)  client_data 
required

A callback function used to start a custom digest calculation, mainly to initialize the calculation process.

Parameters
[in]fileWhen signing a signature, this represents the source file object to be signed.
When verifying a signature field, this represents the source file object to be verified.
[in]byte_range_arrayA byte range array of the signed document(not the source document).
Elements in this array always be in pairs of offset-size values in order of: offset,size,offset,size...
[in]signatureA signature object.
[in]client_dataPointer to a user-defined object, which is passed by user from function FSSignature::startSign:cert_password:digest_algorithm:save_path:client_data:pause: or FSSignature::startVerify:pause:.
Returns
YES means the calculation process is successfully started and then FSSignatureCallback::continueCalcDigest:client_data: will be triggered to continue the calculation process. NO means fail to start a calculation process.

◆ verifySigState:signed_data:client_data:()

- (FSSignatureStates) verifySigState: (NSData *)  digest
signed_data: (NSData *)  signed_data
client_data: (void *)  client_data 
required

A callback function used to do verifying and return the verify state.

Host application provides this callback function for custom sign mechanism. This callback function would be triggered during the signature verifying process.

Parameters
[in]digestThe digest data buffer, for source file buffer to be verified.
[in]signed_dataThe signed data buffer.
[in]client_dataPointer to a user-defined object, which is passed by user from function FSSignature::startSign:cert_password:digest_algorithm:save_path:client_data:pause: or FSSignature::startVerify:pause:.
Returns
Verify state. Please refer to values starting from FSSignatureStateVerifyValid and this should be one or a combination of them.