(Excel) AES Key Wrap / Unwrap

Demonstrates the AesKeyWrap and AesKeyUnwrap methods that were added to Chilkat v9.5.0.66.

This example implements the AES Key Wrap Algorithm as described in RFC 3394. It demonstrates wrapping and unwrapping the test data provided in the RFC. This example requires Chilkat v9.5.0.66 or later.

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' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

' Note: This example requires Chilkat v9.5.0.66 or later.

Dim crypt As Chilkat.Crypt2
Set crypt = Chilkat.NewCrypt2

' The KEK is the Key Encryption Key.  It's the AES key that is used
' to wrap another AES key which is called the "Key Data".

' The KEK can be 128-bit, 192-bit, or 256-bit.  
' (In other words, it can be 16 bytes, 24 bytes, or 32 bytes)

' The Key Data must be a multiple of 64-bits in length.  (i.e. a multiple of 8 bytes)
' The AES Key Wrap algorithm can wrap not only AES keys, but any data that is a
' multiple of 8 bytes in size.


encoding = "hex"

' Use a 128-bit KEK to wrap a 128-bit AES key.
kek = "000102030405060708090A0B0C0D0E0F"
keyData = "00112233445566778899AABBCCDDEEFF"
expected = "1FA68B0A8112B447AEF34BD8FB5A7B829D3E862371D2CFE5"

Debug.Print "---- Use a 128-bit KEK to wrap a 128-bit AES key."
Debug.Print "kek = "; kek
Debug.Print "keyData = "; keyData
Debug.Print "expected = "; expected
wrappedKey = crypt.AesKeyWrap(kek,keyData,encoding)
Debug.Print "computed = "; wrappedKey
unwrappedKey = crypt.AesKeyUnwrap(kek,wrappedKey,encoding)
Debug.Print "unwrapped = "; unwrappedKey
Debug.Print "----"

' Use a 192-bit KEK to wrap a 128-bit AES key.
kek = "000102030405060708090A0B0C0D0E0F1011121314151617"
keyData = "00112233445566778899AABBCCDDEEFF"
expected = "96778B25AE6CA435F92B5B97C050AED2468AB8A17AD84E5D"

Debug.Print "---- Use a 192-bit KEK to wrap a 128-bit AES key."
Debug.Print "kek = "; kek
Debug.Print "keyData = "; keyData
Debug.Print "expected = "; expected
wrappedKey = crypt.AesKeyWrap(kek,keyData,encoding)
Debug.Print "computed = "; wrappedKey
unwrappedKey = crypt.AesKeyUnwrap(kek,wrappedKey,encoding)
Debug.Print "unwrapped = "; unwrappedKey
Debug.Print "----"

' Use a 256-bit KEK to wrap a 128-bit AES key.
kek = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"
keyData = "00112233445566778899AABBCCDDEEFF"
expected = "64E8C3F9CE0F5BA263E9777905818A2A93C8191E7D6E8AE7"

Debug.Print "---- Use a 256-bit KEK to wrap a 128-bit AES key."
Debug.Print "kek = "; kek
Debug.Print "keyData = "; keyData
Debug.Print "expected = "; expected
wrappedKey = crypt.AesKeyWrap(kek,keyData,encoding)
Debug.Print "computed = "; wrappedKey
unwrappedKey = crypt.AesKeyUnwrap(kek,wrappedKey,encoding)
Debug.Print "unwrapped = "; unwrappedKey
Debug.Print "----"

' Use a 192-bit KEK to wrap a 192-bit AES key.
kek = "000102030405060708090A0B0C0D0E0F1011121314151617"
keyData = "00112233445566778899AABBCCDDEEFF0001020304050607"
expected = "031D33264E15D33268F24EC260743EDCE1C6C7DDEE725A936BA814915C6762D2"

Debug.Print "---- Use a 192-bit KEK to wrap a 192-bit AES key."
Debug.Print "kek = "; kek
Debug.Print "keyData = "; keyData
Debug.Print "expected = "; expected
wrappedKey = crypt.AesKeyWrap(kek,keyData,encoding)
Debug.Print "computed = "; wrappedKey
unwrappedKey = crypt.AesKeyUnwrap(kek,wrappedKey,encoding)
Debug.Print "unwrapped = "; unwrappedKey
Debug.Print "----"

' Use a 256-bit KEK to wrap a 192-bit AES key.
kek = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"
keyData = "00112233445566778899AABBCCDDEEFF0001020304050607"
expected = "A8F9BC1612C68B3FF6E6F4FBE30E71E4769C8B80A32CB8958CD5D17D6B254DA1"

Debug.Print "---- Use a 256-bit KEK to wrap a 192-bit AES key."
Debug.Print "kek = "; kek
Debug.Print "keyData = "; keyData
Debug.Print "expected = "; expected
wrappedKey = crypt.AesKeyWrap(kek,keyData,encoding)
Debug.Print "computed = "; wrappedKey
unwrappedKey = crypt.AesKeyUnwrap(kek,wrappedKey,encoding)
Debug.Print "unwrapped = "; unwrappedKey
Debug.Print "----"

' Use a 256-bit KEK to wrap a 256-bit AES key.
kek = "000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F"
keyData = "00112233445566778899AABBCCDDEEFF000102030405060708090A0B0C0D0E0F"
expected = "28C9F404C4B810F4CBCCB35CFB87F8263F5786E2D80ED326CBC7F0E71A99F43BFB988B9B7A02DD21"

Debug.Print "---- Use a 256-bit KEK to wrap a 256-bit AES key."
Debug.Print "kek = "; kek
Debug.Print "keyData = "; keyData
Debug.Print "expected = "; expected
wrappedKey = crypt.AesKeyWrap(kek,keyData,encoding)
Debug.Print "computed = "; wrappedKey
unwrappedKey = crypt.AesKeyUnwrap(kek,wrappedKey,encoding)
Debug.Print "unwrapped = "; unwrappedKey
Debug.Print "----"

' The output:
' 
' 	---- Use a 128-bit KEK to wrap a 128-bit AES key.
' 	kek = 000102030405060708090A0B0C0D0E0F
' 	keyData = 00112233445566778899AABBCCDDEEFF
' 	expected = 1FA68B0A8112B447AEF34BD8FB5A7B829D3E862371D2CFE5
' 	computed = 1FA68B0A8112B447AEF34BD8FB5A7B829D3E862371D2CFE5
' 	unwrapped = 00112233445566778899AABBCCDDEEFF
' 	----
' 	---- Use a 192-bit KEK to wrap a 128-bit AES key.
' 	kek = 000102030405060708090A0B0C0D0E0F1011121314151617
' 	keyData = 00112233445566778899AABBCCDDEEFF
' 	expected = 96778B25AE6CA435F92B5B97C050AED2468AB8A17AD84E5D
' 	computed = 96778B25AE6CA435F92B5B97C050AED2468AB8A17AD84E5D
' 	unwrapped = 00112233445566778899AABBCCDDEEFF
' 	----
' 	---- Use a 256-bit KEK to wrap a 128-bit AES key.
' 	kek = 000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F
' 	keyData = 00112233445566778899AABBCCDDEEFF
' 	expected = 64E8C3F9CE0F5BA263E9777905818A2A93C8191E7D6E8AE7
' 	computed = 64E8C3F9CE0F5BA263E9777905818A2A93C8191E7D6E8AE7
' 	unwrapped = 00112233445566778899AABBCCDDEEFF
' 	----
' 	---- Use a 192-bit KEK to wrap a 192-bit AES key.
' 	kek = 000102030405060708090A0B0C0D0E0F1011121314151617
' 	keyData = 00112233445566778899AABBCCDDEEFF0001020304050607
' 	expected = 031D33264E15D33268F24EC260743EDCE1C6C7DDEE725A936BA814915C6762D2
' 	computed = 031D33264E15D33268F24EC260743EDCE1C6C7DDEE725A936BA814915C6762D2
' 	unwrapped = 00112233445566778899AABBCCDDEEFF0001020304050607
' 	----
' 	---- Use a 256-bit KEK to wrap a 192-bit AES key.
' 	kek = 000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F
' 	keyData = 00112233445566778899AABBCCDDEEFF0001020304050607
' 	expected = A8F9BC1612C68B3FF6E6F4FBE30E71E4769C8B80A32CB8958CD5D17D6B254DA1
' 	computed = A8F9BC1612C68B3FF6E6F4FBE30E71E4769C8B80A32CB8958CD5D17D6B254DA1
' 	unwrapped = 00112233445566778899AABBCCDDEEFF0001020304050607
' 	----
' 	---- Use a 256-bit KEK to wrap a 256-bit AES key.
' 	kek = 000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F
' 	keyData = 00112233445566778899AABBCCDDEEFF000102030405060708090A0B0C0D0E0F
' 	expected = 28C9F404C4B810F4CBCCB35CFB87F8263F5786E2D80ED326CBC7F0E71A99F43BFB988B9B7A02DD21
' 	computed = 28C9F404C4B810F4CBCCB35CFB87F8263F5786E2D80ED326CBC7F0E71A99F43BFB988B9B7A02DD21
' 	unwrapped = 00112233445566778899AABBCCDDEEFF000102030405060708090A0B0C0D0E0F
' 	----
'