d 0f</tt> - OID 2.5.29.15 "KeyUsage"
			<li><tt>01</tt> - universal type boolean
			<li><tt>01</tt> - boolean length 0x1 (1) bytes
			<li><tt>ff</tt> - boolean value "true" (extension is critical)
			<li><tt>04</tt> - universal type octetstring
			<li><tt>04</tt> - octetstring length 0x4 (4) bytes
			<li>(octetstring is a DER document as follows):
			<li><tt>03</tt> - universal type bitstring
			<li><tt>02</tt> - bitstring length 0x2 (2) bytes
			<li><tt>05</tt> - right-pad bitstring by 5 bits
			<li><tt>a0