The CERT_BASIC_CONSTRAINTS2_INFO structure contains information indicating whether the certified subject may act as a CA or an end-entity. If the subject may act as a CA, a certification path length constraint may also be specified.
When the CryptDecodeObject or CryptDecodeObjectEx function is performed on a CERT_EXTENSION structure's Value member, and the structure's pszObjId member is set to "2.5.29.19", this CERT_BASIC_CONSTRAINTS2_INFO is output from the function call.
typedef struct _CERT_BASIC_CONSTRAINTS2_INFO {
BOOL fCA;
BOOL fPathLenConstraint;
DWORD dwPathLenConstraint;
} CERT_BASIC_CONSTRAINTS2_INFO, *PCERT_BASIC_CONSTRAINTS2_INFO;