macros · February 26, 2014 20:59 · Feb 26, 2014
diff --git a/gistfile1.txt b/gistfile1.txt
@@ -0,0 +1,31 @@
+#!/usr/bin/ruby
+
+require 'openssl'
+
+cert = OpenSSL::X509::Certificate.new File.read(ARGV[0])
+cn = cert.subject.to_a.select{|oid, value| oid == "CN"}[0][1]
+
+puts "Cert metadata"
+puts cert.serial
+puts cert.issuer
+puts cert.not_before
+puts cert.not_after
+puts cert.signature_algorithm
+puts cert.to_s
+puts "Public key metadata"
+puts cert.public_key.class
+puts cert.public_key.to_s
+
+
+sans = []
+cert.extensions.each do |ext|
+  next if ext.oid != "subjectAltName"
+  ostr = OpenSSL::ASN1.decode(ext.to_der).value.last
+  sequence = OpenSSL::ASN1.decode(ostr.value)
+  sequence.value.each do |san|
+    sans << san.value
+  end
+end
+
+puts "CN: #{cn}"
+puts "SANS: #{sans.join(', ')}"