foxit::pdf::SignatureCallback Class Referenceabstract

Public Member Functions

virtual common::Progressive::State ContinueCalcDigest (const void *client_data, const common::PauseCallback *pause)=0
 A callback function used to continue the custom digest calculation process. More...
 
virtual String GetDigest (const void *client_data)=0
 A callback function used to get the digest after the calculation process is finished. More...
 
virtual bool IsNeedPadData ()=0
 Check whether to return all contents with padding zero or not, when callback function SignatureCallback::VerifySigState is called. More...
 
virtual void Release ()=0
 A callback function used to release current SignatureCallback object itself. More...
 
virtual String Sign (const void *digest, uint32 digest_length, const wchar_t *cert_path, const WString &cert_password, Signature::DigestAlgorithm digest_algorithm, void *client_data)=0
 A callback function used to do signing and return the signed data. More...
 
virtual bool StartCalcDigest (const common::file::ReaderCallback *file, const uint32 *byte_range_array, uint32 size_of_array, const Signature &signature, const void *client_data)=0
 A callback function used to start a custom digest calculation, mainly to initialize the calculation process. More...
 
virtual uint32 VerifySigState (const void *digest, uint32 digest_length, const void *signed_data, uint32 signed_data_len, void *client_data)=0
 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 common::Library::RegisterSignatureCallback with filter and sub filter as the callback name.

See also
common::Library

Member Function Documentation

◆ ContinueCalcDigest()

virtual common::Progressive::State foxit::pdf::SignatureCallback::ContinueCalcDigest ( const void *  client_data,
const common::PauseCallback pause 
)
pure virtual

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 NULL, it means not to pause during the calculation process. If this is not NULL, please check the the return value of function PauseCallback::NeedToPauseNow and decide when to pause the calculation process.
[in]client_dataA user-defined object, which is passed by user from function Signature::StartSign or Signature::StartVerify.
Returns
common::Progressive::e_Finished means the rendering is finished successfully.
common::Progressive::e_ToBeContinued means the calculation process is not finished yet and callback function SignatureCallback::ContinueCalcDigest would be triggered again to continue the process.
common::Progressive::e_Error means any error occurs.

◆ GetDigest()

virtual String foxit::pdf::SignatureCallback::GetDigest ( const void *  client_data)
pure virtual

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_dataA user-defined object, which is passed by user from function Signature::StartSign or Signature::StartVerify.
Returns
The digest string. If there is any error, please return an empty string.

◆ IsNeedPadData()

virtual bool foxit::pdf::SignatureCallback::IsNeedPadData ( )
pure virtual

Check whether to return all contents with padding zero or not, when callback function SignatureCallback::VerifySigState is called.

Returns
true means to return all data in contents steam (including padding zero), while false means to return contents data without padding zero in stream end.

◆ Release()

virtual void foxit::pdf::SignatureCallback::Release ( )
pure virtual

A callback function used to release current SignatureCallback object itself.

Returns
None.

◆ Sign()

virtual String foxit::pdf::SignatureCallback::Sign ( const void *  digest,
uint32  digest_length,
const wchar_t *  cert_path,
const WString cert_password,
Signature::DigestAlgorithm  digest_algorithm,
void *  client_data 
)
pure virtual

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]digest_lengthThe size of digest data buffer.
[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 Signature::e_DigestSHA1 and this would be one of these values.
[in]client_dataA user-defined object, which is passed by user from function Signature::StartSign or Signature::StartVerify.
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 Signature::SetDefaultContentsLength before signing the unsigned signature.

◆ StartCalcDigest()

virtual bool foxit::pdf::SignatureCallback::StartCalcDigest ( const common::file::ReaderCallback file,
const uint32 byte_range_array,
uint32  size_of_array,
const Signature signature,
const void *  client_data 
)
pure virtual

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]size_of_arrayCount of elements in the byte range array byte_range_array.
[in]signatureA signature object.
[in]client_dataA user-defined object, which is passed by user from function Signature::StartSign or Signature::StartVerify.
Returns
true means the calculation process is successfully started and then SignatureCallback::ContinueCalcDigest will be triggered to continue the calculation process. false means fail to start a calculation process.

◆ VerifySigState()

virtual uint32 foxit::pdf::SignatureCallback::VerifySigState ( const void *  digest,
uint32  digest_length,
const void *  signed_data,
uint32  signed_data_len,
void *  client_data 
)
pure virtual

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]digest_lengthThe size of digest data buffer.
[in]signed_dataThe signed data buffer.
[in]signed_data_lenThe size of signed data buffer.
[in]client_dataA user-defined object, which is passed by user from function Signature::StartSign or Signature::StartVerify.
Returns
Verify state. Please refer to values starting from Signature::e_StateVerifyValid and this should be one or a combination of them.

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