The CERT_ALT_NAME_INFO structure is used to encode/decode subject or issuer extensions.
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 "2.5.29.7" or "2.5.29.8", this CERT_ALT_NAME_INFO is output from the function call.
typedef struct _CERT_ALT_NAME_INFO {
DWORD cAltEntry;
PCERT_ALT_NAME_ENTRY rgAltEntry;
} CERT_ALT_NAME_INFO, *PCERT_ALT_NAME_INFO