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# Certificate Item Attribute Constants

Use these four character values to indicate certificate item attributes.

## Topics

### Constants

[`var kSecSubjectItemAttr: Int`](/documentation/Security/kSecSubjectItemAttr)

DER-encoded subject distinguished name.

[`var kSecIssuerItemAttr: Int`](/documentation/Security/kSecIssuerItemAttr)

DER-encoded issuer distinguished name.

[`var kSecSerialNumberItemAttr: Int`](/documentation/Security/kSecSerialNumberItemAttr)

DER-encoded certificate serial number (without the tag and length).

[`var kSecPublicKeyHashItemAttr: Int`](/documentation/Security/kSecPublicKeyHashItemAttr)

Public key hash.

[`var kSecSubjectKeyIdentifierItemAttr: Int`](/documentation/Security/kSecSubjectKeyIdentifierItemAttr)

Subject key identifier.

[`var kSecCertTypeItemAttr: Int`](/documentation/Security/kSecCertTypeItemAttr)

Certificate type.

[`var kSecCertEncodingItemAttr: Int`](/documentation/Security/kSecCertEncodingItemAttr)

Certificate encoding.


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