The CRYPT_BIT_BLOB structure is used for an array of bits. In a CRYPT_BIT_BLOB the last byte may contain zero to seven unused bits. Therefore, the overall bit length is cbData * 8 – cUnusedBits.
typedef struct _CRYPT_BIT_BLOB {
DWORD cbData;
BYTE* pbData;
DWORD cUnusedBits;
} CRYPT_BIT_BLOB, *PCRYPT_BIT_BLOB;
CERT_BASIC_CONSTRAINTS_INFO, CERT_INFO, CERT_KEY_ATTRIBUTES_INFO, CERT_KEY_USAGE_RESTRICTION_INFO, CERT_PUBLIC_KEY_INFO, CERT_SIGNED_CONTENT_INFO