CryptUnprotectData.md

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Function name : CryptUnprotectData

Group: Cryptography Reference - Library: crypt32

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Decrypts and does an integrity check of the data in a DATA_BLOB structure. Scoped to local computer, or to user credentials.

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Declaration:

BOOL WINAPI CryptUnprotectData(
  __in       DATA_BLOB *pDataIn,
  __out_opt  LPWSTR *ppszDataDescr,
  __in_opt   DATA_BLOB *pOptionalEntropy,
  __in       PVOID pvReserved,
  __in_opt   CRYPTPROTECT_PROMPTSTRUCT *pPromptStruct,
  __in       DWORD dwFlags,
  __out      DATA_BLOB *pDataOut
);  

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FoxPro declaration:

DECLARE INTEGER CryptUnprotectData IN crypt32;
	INTEGER pDataIn,;
	STRING szDataDescr,;
	INTEGER pOptionalEntropy,;
	INTEGER pvReserved,;
	STRING @pPromptStruct,;
	LONG dwFlags,;
	INTEGER @pDataOut  

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Parameters:

pDataIn [in] A pointer to a DATA_BLOB structure that holds the encrypted data.

ppszDataDescr [out, optional] A pointer to a string-readable description of the encrypted data included with the encrypted data.

pOptionalEntropy [in, optional] A pointer to a DATA_BLOB structure that contains a password or other additional entropy used when the data was encrypted.

pPromptStruct [in, optional] A pointer to a CRYPTPROTECT_PROMPTSTRUCT structure that provides information about where and when prompts are to be displayed.

dwFlags [in] This parameter can be one of several predefined flags.

pDataOut [out] A pointer to a DATA_BLOB structure that receives the decrypted data.

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Return value:

If the function succeeds, the function returns TRUE.

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Comments:

When you have finished using sensitive information, clear it from memory by calling the SecureZeroMemory function.

See also: CryptProtectData, CryptProtectMemory, CryptUnprotectMemory.

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