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What is ExtendedKeyUsage?
ExtendedKeyUsage is a Certificate Extensions and consists of a list of usages indicating purposes for which the certificate public key can be used for. These can either be object short names of the dotted numerical form of OIDs. While any OID can be used only certain values make sense.
What is data encipherment?
DataEncipherment is a KeyUsage bit that is asserted when the Certificate Subject Public Key is used for direct Encryption of raw user data without the use of an intermediate symmetric cipher. DataEncipherment bit means that the key in the certificate is used for Encryption of the application data.
Can a certificate be used for an extended key?
Extended key usage further refines key usage extensions. An extended key is either critical or non-critical. If the extension is critical, the certificate must be used only for the indicated purpose or purposes. If the certificate is used for another purpose, it is in violation of the CA’s policy.
What’s the difference between extended key usage and enhanced key usage?
I’ve seen both the terms Enhanced Key Usage and Extended Key Usage, and both were abbreviated as EKU. Do both refer to the same extension or property? The correct name for the standard extension is Extended Key Usage; see section 4.2.1.12 of RFC 5280. Its OID is 2.5.29.37. Confusion comes from Microsoft documentation and software:
What do I need to know about the extendedKeyUsage object?
The ExtendedKeyUsage object provides read-only access to the extended key usage (EKU) properties of a certificate. The ExtendedKeyUsage object has these types of members: The ExtendedKeyUsage object has these properties. EKUs collection that contains the EKU objects for the certificate.
What is extended key usage or simply EKU?
What is Extended Key Usage or simply EKU (Microsoft calls it Enhanced Key Usage, but they both share the same abbreviation)? RFC 5280 §4.2.1.12 says: This extension indicates one or more purposes for which the certified public key may be used, in addition to or in place of the basic purposes indicated in the key usage extension.