CRYPT_ECC_CMS_SHARED_INFO structure (wincrypt.h)
The CRYPT_ECC_CMS_SHARED_INFO structure represents key-encryption key information when using Elliptic Curve Cryptography (ECC) in the Cryptographic Message Syntax (CMS) EnvelopedData content type. This structure is used in a key-exchange scenario for exchange of keys to encrypt and decrypt content. A pointer to this structure can be used in the pvStructInfo parameter of CryptEncodeObject or CryptDecodeObject and is specified by the constant ECC_CMS_SHARED_INFO. For more information, see Constants for CryptEncodeObject and CryptDecodeObject.
Syntax
typedef struct _CRYPT_ECC_CMS_SHARED_INFO {
CRYPT_ALGORITHM_IDENTIFIER Algorithm;
CRYPT_DATA_BLOB EntityUInfo;
BYTE rgbSuppPubInfo[CRYPT_ECC_CMS_SHARED_INFO_SUPPPUBINFO_BYTE_LENGTH];
} CRYPT_ECC_CMS_SHARED_INFO, *PCRYPT_ECC_CMS_SHARED_INFO;
Members
Algorithm
A CRYPT_ALGORITHM_IDENTIFIER structure that contains the object identifier of the key-encryption algorithm used to wrap the content-encryption key.
EntityUInfo
An optional member that contains additional user keying material as an octet string supplied by the sending agent.
rgbSuppPubInfo[CRYPT_ECC_CMS_SHARED_INFO_SUPPPUBINFO_BYTE_LENGTH]
An array of four bytes that represent the length, in bits, of the key-encryption key. The byte array is in little-endian order.
The following table contains the definition of the array dimension.
CRYPT_ECC_CMS_SHARED_INFO_SUPPPUBINFO_BYTE_LENGTH (4)
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows Vista [desktop apps only] |
| Minimum supported server | Windows Server 2008 [desktop apps only] |
| Header | wincrypt.h |