CPSetKeyParam

The CPSetKeyParam function customizes the operations of a key.

BOOL CPSetKeyParam(
  HCRYPTPROV hProv,        // in
  HCRYPTKEY hKey,          // in
  DWORD dwParam,           // in
  BYTE *pbData,            // in
  DWORD dwFlags            // in
);

Parameters

hProv

Handle to a particular key container within the CSP. This handle is obtained with a call to CPAcquireContext.

hKey

Handle to the target key on which to set parameters.

dwParam

The following table list currently defined dwParam values.

Value	Contents of the pbData buffer
KP_SALT	A BYTE array containing the key's current salt value.
KP_SALT_EX	A BYTE array containing the key's current salt value. This parameter is not used with public/private key pairs. If hKey references a public/private key pair, the NTE_BAD_TYPE error code is returned.
KP_ PERMISSIONS	A DWORD defining the key's permission flags. Flags can be combined using bitwise OR operations. See the table in the Remarks section for key permission flag values and their meanings.
KP_IV	A BYTE array containing the key's current initialization Vector (IV).
KP_PADDING	A DWORD indicating the padding method used by the key's cipher. PKCS5_PADDING is the only padding method value defined. It represents PKCS 5 ( sec 6.2) padding.
KP_MODE	A DWORD indicating the cipher mode. See the Remarks section for a table of possible cipher modes.
KP_MODE_BITS	A DWORD indicating the feedback width, in bits. This parameter only applies when the OFB or CFB cipher modes are used.
KP_EFFECTIVE_ KEYLEN	A Microsoft base provider implementation compatible CSP using RC2 must support KP_EFFECTIVE_KEYLEN used to set the effective key length of an RC2 key.

Parameters can be added as needed. General-purpose parameters can be define in coordination with Microsoft to promote cross-vendor standardization and allow the new parameter numbers to be added to the standard Microsoft Win32® header files..

pbData

Parameter data buffer. Upon entry to the function, this buffer will contain the data that corresponds to the dwParam parameter value. Notice that the length of this data is not explicitly specified but is implied by the dwParam parameter value.

dwFlags

No flags are currently defined.

Return Values

If the function succeeds, the return value is TRUE.

If the function fails, the return value is FALSE, and the appropriate error code from the following table must be set using SetLastError.

Remarks

The following table lists the defined permission flags:

The following table lists the defined cipher modes:

Requirements

  Windows NT/2000: Requires Windows NT 4.0 or later.
  Windows 95/98: Requires Windows 95 OSR2 or later (or Windows 95 with Internet Explorer 3.02 or later).
  Header: Declared in Wincrypt.h.

See Also

CPGenKey, CPGetKeyParam, CryptSetKeyParam