CryptEnumProviderTypes

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11/18/2015

A version of this page is also available for

4/8/2010

This function retrieves the first or next type of cryptographic service provider (CSP) supported on the computer. Used in a loop, this function retrieves in sequence all of the CSP types available on a computer.

Syntax

BOOL WINAPI CryptEnumProviderTypes( 
  DWORD dwIndex,
  DWORD* pdwReserved, 
  DWORD dwFlags, 
  DWORD* pdwProvType,
  LPTSTR pszTypeName, 
  DWORD* pcbTypeName
);

Parameters

dwIndex
[in] Specifies the index of the next provider type to be enumerated.

pdwReserved
[in] Reserved for future use and must be set to NULL.

dwFlags
[in] Reserved for future use and must be set to zero.

pdwProvType
[in] Pointer to the DWORD value that designates the enumerated provider type.

pszTypeName
[out] Pointer to a buffer that receives a null-terminated string from the enumerated provider type. When the provider types have no friendly names, no name is returned and the DWORD value pointed to by pcbTypeName is zero.

This parameter can be NULL if you want to get the size of the name for memory allocation purposes.

pcbTypeName
[in, out] On input, pointer to a DWORD value that specifies the size, in bytes, of the buffer pointed to by the pszTypeName parameter. On output, the DWORD value contains the number of bytes stored in the buffer. When the provider types have no friendly names, no name is returned and the DWORD value pointed to by pcbTypeName is zero.

When processing the data returned in the buffer, applications must use the actual size of the data returned. The actual size may be slightly smaller than the size of the buffer specified on input. On input, buffer sizes are usually specified large enough to ensure that the largest possible output data will fit in the buffer. On output, the variable pointed to by this parameter is updated to reflect the actual size of the data copied to the buffer.

Return Value

TRUE indicates success. FALSE indicates failure. To get extended error information, call the GetLastError function.

The following table shows the common values for the GetLastError function. The error values prefaced by NTE are generated by the particular CSP you are using.

Value	Description
ERROR_NO_MORE_ITEMS	There are no more items to enumerate.
ERROR_NOT_ENOUGH_MEMORY	The operating system ran out of memory.
NTE_BAD_FLAGS	dwFlags has an unrecognized value.
NTE_FAIL	Something was wrong with the type registration.

Remarks

This function enumerates the provider types on a device. Once this is done, the providers for a specific type may be enumerated by using the CryptEnumProviders function.

Windows Embedded CE does not support the ANSI version of this function.

Example Code

long i;
DWORD dwErr;
// Loop through enumerating provider types.
for (i=0;;i++)
{
if (!CryptEnumProviderTypes(i, NULL, 0, &dwType, NULL, NULL))
 {if (ERROR_NO_MORE_ITEMS != (dwErr = GetLastError()))
 {printf("ERROR - CryptEnumProviderTypes : %X\n", dwErr);
 }
 break;
 }
printf ("Provider Type %d\n", dwType);
}

Requirements

Header	wincrypt.h
Library	coredll.lib
Windows Embedded CE	Windows CE 2.10 and later
Windows Mobile	Windows Mobile Version 5.0 and later

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