Get the subject’s key identifier from the subjectKeyIdentifier exteension, as described in RFC5280 Section 4.2.1.2.
Returns the binary String key identifier or nil or raises ASN1::ASN1Error.
# File openssl/lib/openssl/x509.rb, line 96
def subject_key_identifier
ext = find_extension("subjectKeyIdentifier")
return nil if ext.nil?
ski_asn1 = ASN1.decode(ext.value_der)
if ext.critical? || ski_asn1.tag_class != :UNIVERSAL || ski_asn1.tag != ASN1::OCTET_STRING
raise ASN1::ASN1Error, "invalid extension"
end
ski_asn1.value
end