Ruby function returns public key certificate from iOS provision profile. Returns OpenSSL::X509::Certificate object.

cert_from_provission.rb

require 'openssl'
require 'open3'
require 'plist'

PROVISIONS = "#{Dir.home}/Library/MobileDevice/Provisioning\ Profiles/".freeze
def get_cert(uuid)
  path = File.join PROVISIONS, "#{uuid}.mobileprovision"
  o, e, s = Open3.capture3("security cms -D -i '#{path}'")
    if s.exitstatus != 0
      raise "Can't extract plist from provision profile\n" + e
  end
  
  provision_plist = Plist.parse_xml(o)
  cert_data = provision_plist['DeveloperCertificates'][0].string
  cert = OpenSSL::X509::Certificate.new(cert_data)
  return cert
end

        

and when...

puts cert.to_text