CMSG_CTRL_DECRYPT_PARA (Compact 2013)

3/28/2014

This structure contains information used to decrypt an enveloped message for a key transport recipient. This structure is passed to CryptMsgControl if the dwCtrlType parameter is CMSG_CTRL_DECRYPT.

Important changes affecting the handling of enveloped messages have been made to CryptoAPI to support S/MIME e-mail interoperability. For details, see the Remarks section of CryptMsgOpenToEncode.

Syntax

typedef struct _CMSG_CTRL_DECRYPT_PARA {
  DWORD cbSize;
  HCRYPTPROV hCryptProv;
  DWORD dwKeySpec;
  DWORD dwRecipientIndex;
} CMSG_CTRL_DECRYPT_PARA, *PCMSG_CTRL_DECRYPT_PARA;

Members

  • cbSize
    Size of this structure in bytes.
  • hCryptProv
    Cryptographic service provider (CSP) handle.
  • dwKeySpec
    The private key to be used.

    The following dwKeySpec values are defined for the default provider.

    Value

    Description

    AT_KEYEXCHANGE

    Keys used to encrypt/decrypt session keys.

    AT_SIGNATURE

    Keys used to create and verify digital signatures.

    If dwKeySpec is zero, the default AT_KEYEXCHANGE is used.

  • dwRecipientIndex
    Index of the recipient in the message associated with the hCryptProv private key.

Requirements

Header

wincrypt.h

See Also

Reference

Cryptography Structures