BCryptQueryProviderRegistration function (bcrypt.h)

Article
10/13/2021

The BCryptQueryProviderRegistration function retrieves information about a CNG provider.

Syntax

NTSTATUS BCryptQueryProviderRegistration(
  [in]      LPCWSTR             pszProvider,
  [in]      ULONG               dwMode,
  [in]      ULONG               dwInterface,
  [in, out] ULONG               *pcbBuffer,
  [in, out] PCRYPT_PROVIDER_REG *ppBuffer
);

Parameters

[in] pszProvider

A pointer to a null-terminated Unicode string that contains the name of the provider to obtain information about.

[in] dwMode

Specifies the type of information to retrieve. This can be one of the following values.

Value	Meaning
CRYPT_ANY	Retrieve any information for the provider.
CRYPT_UM	Retrieve the user mode information for the provider.
CRYPT_KM	Retrieve the kernel mode information for the provider.
CRYPT_MM	Retrieve both the user mode and kernel mode information for the provider.

[in] dwInterface

Specifies the interface to retrieve information for. This can be one of the following values.

Value	Meaning
BCRYPT_ASYMMETRIC_ENCRYPTION_INTERFACE	Retrieve the asymmetric encryption interface.
BCRYPT_CIPHER_INTERFACE	Retrieve the cipher interface.
BCRYPT_HASH_INTERFACE	Retrieve the hash interface.
NCRYPT_KEY_STORAGE_INTERFACE	Retrieve the key storage interface.
BCRYPT_RNG_INTERFACE	Retrieve the random number generator interface.
NCRYPT_SCHANNEL_INTERFACE	Retrieve the Schannel interface.
BCRYPT_SECRET_AGREEMENT_INTERFACE	Retrieve the secret agreement interface.
BCRYPT_SIGNATURE_INTERFACE	Retrieve the signature interface.

[in, out] pcbBuffer

A pointer to a ULONG value that, on entry, contains the size, in bytes, of the buffer pointed to by the ppBuffer parameter. On exit, this value receives either the number of bytes copied to the buffer or the required size, in bytes, of the buffer.

Note This is the total size, in bytes, of the entire buffer, not just the size of the CRYPT_PROVIDER_REG structure. The buffer must be able to hold other data for the providers in addition to the CRYPT_PROVIDER_REG structure.

[in, out] ppBuffer

A pointer to a buffer pointer that receives a CRYPT_PROVIDER_REG structure and other data that describes the provider.

If this parameter is NULL, this function will return STATUS_BUFFER_TOO_SMALL and place in the value pointed to by the pcbBuffer parameter, the required size, in bytes, of all data.

If this parameter is the address of a NULL pointer, this function will allocate the required memory, fill it in with the provider information, and place a pointer to this memory in this parameter. When you have finished using this memory, free it by passing this pointer to the BCryptFreeBuffer function.

If this parameter is the address of a non-NULL pointer, this function will copy the provider information into this buffer. The pcbBuffer parameter must contain the size, in bytes, of the entire buffer. If the buffer is not large enough to hold all of the provider information, this function will return STATUS_BUFFER_TOO_SMALL.

Return value

Returns a status code that indicates the success or failure of the function.

Possible return codes include, but are not limited to, the following.

Return code	Description
STATUS_SUCCESS	The function was successful.
STATUS_INVALID_PARAMETER	One or more parameters are not valid.
STATUS_BUFFER_TOO_SMALL	The size specified by the pcbBuffer parameter is not large enough to hold all of the data.
STATUS_NOT_FOUND	No provider could be found that matches the specified criteria.

Remarks

BCryptQueryProviderRegistration can be called only in user mode.

Requirements

Requirement	Value
Minimum supported client	Windows Vista [desktop apps only]
Minimum supported server	Windows Server 2008 [desktop apps only]
Target Platform	Windows
Header	bcrypt.h
Library	Bcrypt.lib
DLL	Bcrypt.dll