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| CryptGetProvParam The CryptGetProvParam function lets applications retrieve parameters that govern the operations of a CSP. VB4-32,5,6
eclare Function CryptGetProvParam Lib "advapi32.dll" (ByVal hProv As Long, ByVal dwParam As Long, pbData As Any, pdwDataLen As Long, ByVal dwFlags As Long) As Long |
VB.NET
System.Security.Cryptography.* |
| Operating Systems Supported |
| Windows NT 4.0 or later; Windows 95 OSR2 or later (or Windows 95 with Internet Explorer 3.02 or later) |
· hProv
[in] A handle to the CSP on which to query parameters.
· dwParam
[in] The parameter number. See the “Remarks” section for a list of valid parameters.
· pbData
[out] The parameter data buffer. The function will copy the specified parameter data to this buffer. The form of this data will vary, depending on the parameter number.
This parameter can be NULL if all you are doing is determining the number of bytes required for the returned parameter data.
· pdwDataLen
[in/out] The address of the parameter data length. Before calling this function, the caller should set this parameter to the length, in bytes, of the pbData buffer. Upon return, this address will contain the number of bytes of parameter data copied to the buffer.
If the buffer specified by pbData is not large enough to hold the data, the function returns the ERROR_MORE_DATA error code through the GetLastError function, and stores the required buffer size in bytes into the variable pointed to by pdwDataLen.
If pbData is NULL, then no error is returned and the function stores the size of the data in bytes in the variable pointed to by pdwDataLen.
Note When one of the enumeration parameters (PP_ENUMALGS or PP_ENUMCONTAINERS) is being read, the pdwDataLen parameter works somewhat differently. If pbData is NULL or the value pointed to pdwDataLen is too small, the value returned in this parameter is the size of the largest item in the enumeration list instead of the size of the item currently being read.
When one of the enumeration parameters is read and the pbData parameter is NULL, the CRYPT_FIRST flag must be specified in order for the size information to be correctly retrieved.
· dwFlags
[in] The flag values. This parameter is normally set to zero.
When one of the enumeration parameters (PP_ENUMALGS or PP_ENUMCONTAINERS) is being read, then the CRYPT_FIRST flag can be specified. When this flag is set, the first item in the enumeration list is returned. If this flag is not set, then the next item in the list is returned. |
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To retrieve extended error information, use the GetLastError function.
The following table lists the error codes most commonly returned by the GetLastError function. The error codes prefaced by “NTE” are generated by the particular CSP you are using.
ERROR_INVALID_HANDLE
One of the parameters specifies an invalid handle.
ERROR_INVALID_PARAMETER
One of the parameters contains an invalid value. This is most often an illegal pointer.
ERROR_NO_MORE_ITEMS
The end of the enumeration list has been reached. No valid data has been placed in the pbData buffer. This error is only returned when dwParam equals PP_ENUMALGS or PP_ENUMCONTAINERS.
NTE_BAD_FLAGS
The dwFlags parameter is nonzero.
NTE_BAD_TYPE
The dwParam parameter specifies an unknown parameter number.
NTE_BAD_UID
The CSP context specified by hProv is invalid. |
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