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The CLAIM_SECURITY_ATTRIBUTE_OCTET_STRING_RELATIVE structure specifies an octet string.<78>

 typedef struct _CLAIM_SECURITY_ATTRIBUTE_OCTET_STRING_RELATIVE {
   DWORD Length;
   BYTE OctetString[];
 } CLAIM_SECURITY_ATTRIBUTE_OCTET_STRING_RELATIVE,
  *PCLAIM_SECURITY_ATTRIBUTE_OCTET_STRING_RELATIVE;

Length: The length, in bytes, of the value contained in the OctetString field.

OctetString: An array of bytes containing the octet string value. The length of the value is specified by the Length field.