require 'chef'
require 'mixlib/shellout'
require 'ffi'
require "chef/win32/api"
require 'openssl'

module Cert
  extend Chef::ReservedNames::Win32::API
  extend FFI::Library

  ffi_lib 'Crypt32'

  ###############################################
  # Win32 API Constants
  ###############################################

  CERT_CLOSE_STORE_CHECK_FLAG                         = 0
  CERT_CLOSE_STORE_FORCE_FLAG                         = 1

  # cert encoding flags.
  CRYPT_ASN_ENCODING                                  = 0x00000001
  CRYPT_NDR_ENCODING                                  = 0x00000002
  X509_ASN_ENCODING                                   = 0x00000001
  X509_NDR_ENCODING                                   = 0x00000002
  PKCS_7_ASN_ENCODING                                 = 0x00010000
  PKCS_7_NDR_ENCODING                                 = 0x00020000
  PKCS_7_OR_X509_ASN_ENCODING                         = (PKCS_7_ASN_ENCODING | X509_ASN_ENCODING)

  # Certificate Display Format
  CERT_NAME_EMAIL_TYPE                                = 1
  CERT_NAME_RDN_TYPE                                  = 2
  CERT_NAME_ATTR_TYPE                                 = 3
  CERT_NAME_SIMPLE_DISPLAY_TYPE                       = 4
  CERT_NAME_FRIENDLY_DISPLAY_TYPE                     = 5
  CERT_NAME_DNS_TYPE                                  = 6
  CERT_NAME_URL_TYPE                                  = 7
  CERT_NAME_UPN_TYPE                                  = 8

  # Retrieve Certificates flag
  CERT_FIND_SUBJECT_STR                               = 0x00080007
  CERT_FIND_ISSUER_STR                                = 0x00080004

  # List Certificates Flag
  CERT_NAME_ISSUER_FLAG                               = 0x1
  CERT_NAME_DISABLE_IE4_UTF8_FLAG                     = 0x00010000
  CERT_NAME_SEARCH_ALL_NAMES_FLAG                     = 0x2
  CERT_NAME_STR_ENABLE_PUNYCODE_FLAG                  = 0x00200000

  # Define ffi pointer
  HCERTSTORE                                          = FFI::TypeDefs[:pointer]
  HCRYPTPROV_LEGACY                                   = FFI::TypeDefs[:pointer]
  PCCERT_CONTEXT                                      = FFI::TypeDefs[:pointer]
  BYTE                                                = FFI::TypeDefs[:pointer]
  DWORD                                               = FFI::TypeDefs[:uint32]
  BLOB                                                = FFI::TypeDefs[:ulong]
  LPSTR                                               = FFI::TypeDefs[:pointer]
  LPCTSTR                                             = FFI::TypeDefs[:pointer]
  BOOL                                                = FFI::TypeDefs[:bool]
  INT_PTR                                             = FFI::TypeDefs[:int]
  LONG                                                = FFI::TypeDefs[:long]
  LPVOID                                              = FFI::TypeDefs[:pointer]
  LPTSTR                                              = FFI::TypeDefs[:pointer]
  LMSTR                                               = FFI::TypeDefs[:pointer]
  PWSTR                                               = FFI::TypeDefs[:pointer]
  PCERT_INFO                                          = FFI::TypeDefs[:pointer]

  class FILETIME < FFI::Struct
    layout :dwLowDateTime, DWORD,
           :dwHighDateTime, DWORD
  end

  class CRYPT_INTEGER_BLOB < FFI::Struct
    layout :cbData, DWORD,   # Count, in bytes, of data
           :pbData, :pointer  # Pointer to data buffer
  end

  class CERT_EXTENSION < FFI::Struct
    layout :pszObjId, LPTSTR,
           :fCritical, BOOL,
           :Value, CRYPT_INTEGER_BLOB
  end

  class CRYPT_BIT_BLOB < FFI::Struct
    layout :cbData, DWORD,
           :pbData, BYTE,
           :cUnusedBits, DWORD
  end

  class CRYPT_ALGORITHM_IDENTIFIER < FFI::Struct
    layout :pszObjId, LPSTR,
           :Parameters, CRYPT_INTEGER_BLOB
  end

  class CERT_PUBLIC_KEY_INFO < FFI::Struct
    layout :Algorithm, CRYPT_ALGORITHM_IDENTIFIER,
           :PublicKey, CRYPT_BIT_BLOB
  end

  class CERT_INFO < FFI::Struct
    layout :dwVersion, DWORD,
         :SerialNumber, CRYPT_INTEGER_BLOB,
         :SignatureAlgorithm, CRYPT_ALGORITHM_IDENTIFIER,
         :Issuer, CRYPT_INTEGER_BLOB,
         :NotBefore, FILETIME,
         :NotAfter, FILETIME,
         :Subject, CRYPT_INTEGER_BLOB,
         :SubjectPublicKeyInfo, CERT_PUBLIC_KEY_INFO,
         :IssuerUniqueId, CRYPT_BIT_BLOB,
         :SubjectUniqueId, CRYPT_BIT_BLOB,
         :cExtension, DWORD,
         :rgExtension, CERT_EXTENSION
  end

  ###############################################################################
  # Windows Function
  # To know description about below windows function
  # Search Ref: https://msdn.microsoft.com/en-us/library/windows/desktop/aa376560
  ###############################################################################

  # To opens the most common system certificate store
  safe_attach_function :CertOpenSystemStoreW, [HCRYPTPROV_LEGACY, LPCTSTR], HCERTSTORE
  # To close the already open certificate store
  safe_attach_function :CertCloseStore, [HCERTSTORE, DWORD], BOOL
  # To retrieve specific certificates from certificate store
  safe_attach_function :CertFindCertificateInStore, [HCERTSTORE, DWORD, DWORD, DWORD, LPVOID, PCCERT_CONTEXT], PCCERT_CONTEXT
  # The CertVerifyTimeValidity function verifies the time validity of a certificate
  safe_attach_function :CertVerifyTimeValidity, [FILETIME, PCERT_INFO], LONG

end

##################################################

include Chef::Mixin::WideString
include Cert

store_handler = CertOpenSystemStoreW(nil, wstring("Root"))

# Expired
certificate_name = "Microsoft Authenticode(tm) Root Authority"
# Valid
certificate_name = "AddTrust External CA Root"

if ( !certificate_name.empty? && pCertContext = CertFindCertificateInStore(store_handler, X509_ASN_ENCODING, 0, CERT_FIND_ISSUER_STR, certificate_name.to_wstring, nil) and not pCertContext.null? )
  pTargetCertInfo = CERT_INFO.new(pCertContext)
  case CertVerifyTimeValidity(nil, pTargetCertInfo)
  when -1
    puts "Certificate is not valid yet."
  when 1
    puts "Certificate is expired."
  when 0
    puts "Certificate's time is valid."
  else
    puts "Certificate time validity not matched."
  end
end

CertCloseStore(store_handler, CERT_CLOSE_STORE_FORCE_FLAG)