Android Question Result encrypt changes according to device !!!

[vecino]

Hello, I have encountered a very strange problem.
I use some functions to encrypt texts that have always worked well.
The functions are copied from a message from these forums. They have been working correctly for years. But not now.
In some new devices (tablets) the results are different.
These are the functions:

Sub Encrypt(dataToEncrypt As String ) As String
  Dim kg As KeyGenerator
  Dim c As Cipher
  Dim B64 As Base64
  Dim bconv As ByteConverter
  Dim data(0) As Byte
  Dim iv(0) As Byte
    '
  iv = Array As Byte(211, 5, 233, 24, 55, 166, 7, 88) ' 16 bytes for AES
  c.Initialize("DESEDE/CBC/PKCS5Padding")   
  c.InitialisationVector = iv
  kg.Initialize("DESEDE")
  kg.KeyFromBytes(bconv.StringToBytes("1234567890123456","ASCII"))
  data = bconv.StringToBytes(dataToEncrypt, "ASCII")
  data = c.Encrypt(data, kg.Key, True)             
    '
  Return B64.EncodeBtoS(data, 0, data.Length)
End Sub

Sub Decrypt(encryptedData As String ) As String   
  Dim kg As KeyGenerator
  Dim c As Cipher
  Dim B64 As Base64
  Dim bconv As ByteConverter
  Dim data(0) As Byte
  Dim iv(0) As Byte
   '
  iv = Array As Byte(211, 5, 233, 24, 55, 166, 7, 88) ' 16 bytes for AES
  c.Initialize("DESEDE/CBC/PKCS5Padding")   
  c.InitialisationVector = iv
  kg.Initialize("DESEDE")   
  kg.KeyFromBytes(bconv.StringToBytes("1234567890123456","ASCII"))
  data = B64.DecodeStoB(encryptedData)
  data = c.Decrypt(data, kg.Key, True) 
   '
   Return bconv.StringFromBytes(data, "ASCII")
End Sub

Sub getEncoded( cCadena As String ) As String
    Dim data() As Byte
    Dim su As StringUtils
    Dim encoded As String
    '
    data = cCadena.GetBytes("ASCII")
    encoded = su.EncodeBase64(data)
    '
    Return (encoded)
End Sub

Sub getDecoded( cCadena As String ) As String 
    Dim data() As Byte
    Dim su As StringUtils
    Dim decoded As String     
    '
    data = su.DecodeBase64(cCadena)
    decoded = BytesToString(data, 0, data.Length, "ASCII")
    '
    Return (decoded) 
End Sub

This is the code I am using to test.

    cHoInt = "Hi this Is a test."
    cUsInt = "This Is the second line."
    cPaInt = "And here the text ends."
    Log("cHoInt: "&cHoInt)
    Log("cUsInt: "&cUsInt)
    Log("cPaInt: "&cPaInt)

    cHoInt = uf.Encrypt(cHoInt)
    cUsInt = uf.Encrypt(cUsInt)
    cPaInt = uf.Encrypt(cPaInt)
    Log("cHoInt: "&cHoInt)
    Log("cUsInt: "&cUsInt)
    Log("cPaInt: "&cPaInt)
  
    cHoInt = uf.getEncoded(cHoInt)
    cUsInt = uf.getEncoded(cUsInt)
    cPaInt = uf.getEncoded(cPaInt)   
    Log("cHoInt: "&cHoInt)
    Log("cUsInt: "&cUsInt)
    Log("cPaInt: "&cPaInt)
  
    Log("<<<")

    cHoInt = uf.getDecoded(cHoInt)
    cUsInt = uf.getdecoded(cUsInt)
    cPaInt = uf.getdecoded(cPaInt)
    Log("cHoInt: "&cHoInt)
    Log("cUsInt: "&cUsInt)
    Log("cPaInt: "&cPaInt)

    cHoInt = uf.Decrypt(cHoInt)
    cUsInt = uf.dEcrypt(cUsInt)
    cPaInt = uf.dEcrypt(cPaInt)
    Log("cHoInt: "&cHoInt)
    Log("cUsInt: "&cUsInt)
    Log("cPaInt: "&cPaInt)

And this is the result with one tablet and another.

cHoInt: Hi this Is a test.
cUsInt: This Is the second line.
cPaInt: And here the text ends.
cHoInt: 4H1xC4N9yngRoynRep9L2/OMePLBzbfQ
cUsInt: 4hDzX80C+KrJ4BTCPmp6NQzN0VKqnhjfakBF6kTM38I=
cPaInt: lDsPRRRH3CbRqfKd/qVFH/P2WPVRgHda
cHoInt: NEgxeEM0Tjl5bmdSb3luUmVwOUwyL09NZVBMQnpiZlE=
cUsInt: NGhEelg4MEMrS3JKNEJUQ1BtcDZOUXpOMFZLcW5oamZha0JGNmtUTTM4ST0=
cPaInt: bERzUFJSUkgzQ2JScWZLZC9xVkZIL1AyV1BWUmdIZGE=
<<<
cHoInt: 4H1xC4N9yngRoynRep9L2/OMePLBzbfQ
cUsInt: 4hDzX80C+KrJ4BTCPmp6NQzN0VKqnhjfakBF6kTM38I=
cPaInt: lDsPRRRH3CbRqfKd/qVFH/P2WPVRgHda
cHoInt: Hi this Is a test.
cUsInt: This Is the second line.
cPaInt: And here the text ends.

cHoInt: Hi this Is a test.
cUsInt: This Is the second line.
cPaInt: And here the text ends.
cHoInt: 8LqUm4ka+bZV97Ht47vPUMxFi+IOCOom
cUsInt: equI+tGF8Ekf4J3UuLsPRGmCny4+iOTxU+jz+mz4Rnk=
cPaInt: yS9U2DuvH5pLDMJ6Rj6zSYF/0EwYkxsM
cHoInt: OExxVW00a2ErYlpWOTdIdDQ3dlBVTXhGaStJT0NPb20=
cUsInt: ZXF1SSt0R0Y4RWtmNEozVXVMc1BSR21Dbnk0K2lPVHhVK2p6K216NFJuaz0=
cPaInt: eVM5VTJEdXZINXBMRE1KNlJqNnpTWUYvMEV3WWt4c00=
<<<
cHoInt: 8LqUm4ka+bZV97Ht47vPUMxFi+IOCOom
cUsInt: equI+tGF8Ekf4J3UuLsPRGmCny4+iOTxU+jz+mz4Rnk=
cPaInt: yS9U2DuvH5pLDMJ6Rj6zSYF/0EwYkxsM
cHoInt: Hi this Is a test.
cUsInt: This Is the second line.
cPaInt: And here the text ends.

Please, someone who enlightens my mind.

 

[Erel]

Are you able to decrypt the data with the encrypted output coming from a different device?

 

[vecino]

Hello, it can not be done, that's the problem. It does not generate the same results. Shows invalid data errors. The program crashes.

 

[Erel]

Please upload a small project with this code.

 

[vecino]

Hello, here is the test project.

This is the result with a tablet:

Logger connected to:  samsung SM-T805
--------- beginning of main
--------- beginning of system
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
>>> Encrypt...
cText: Hi this Is a test.
cText: 8LqUm4ka+bZV97Ht47vPUMxFi+IOCOom
cText: OExxVW00a2ErYlpWOTdIdDQ3dlBVTXhGaStJT0NPb20=
<<< Decrypt...
cText: 8LqUm4ka+bZV97Ht47vPUMxFi+IOCOom
cText: Hi this Is a test.
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = true **

This is the result with another tablet:

Logger connected to:  unknown miTab LIVE
--------- beginning of /dev/log/main
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
>>> Encrypt...
cText: Hi this Is a test.
cText: 4H1xC4N9yngRoynRep9L2/OMePLBzbfQ
cText: NEgxeEM0Tjl5bmdSb3luUmVwOUwyL09NZVBMQnpiZlE=
<<< Decrypt...
cText: 4H1xC4N9yngRoynRep9L2/OMePLBzbfQ
cText: Hi this Is a test.
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = true **

 

[KMatle]

You are using triple des ("DESEDE"). As I know the implementation is different on several devices if you don't use it correct.

I strongly recommend you to change to AES-256 and try again.

 

[vecino]

Hello, thanks for the information.
Can you tell me how is that?
I only copied and pasted these functions. I do not know the possible parameters.

 

[vecino]

I have made these changes, I do not know if it is right to make them that way.

iv = Array As Byte(211, 5, 233, 24, 55, 166, 7, 88,  211, 5, 233, 24, 55, 166, 7, 88) ' 16 bytes for AES
c.Initialize("AES/CBC/PKCS5Padding")     
kg.Initialize("AES")

The result is also not valid, different data are obtained in different devices.

>>> Encrypt...
cText: Hi this Is a test.
cText: 8LqUm4ka+bZV97Ht47vPUMxFi+IOCOom
cText: OExxVW00a2ErYlpWOTdIdDQ3dlBVTXhGaStJT0NPb20=
<<< Decrypt...
cText: 8LqUm4ka+bZV97Ht47vPUMxFi+IOCOom
cText: Hi this Is a test.
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = true **



--------- beginning of system
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
>>> Encrypt...
cText: Hi this Is a test.
cText: Br7vnGS+yj6VLksyuQu3qQgvKoS3mHOeurSpit1Yyl8=
cText: QnI3dm5HUyt5ajZWTGtzeXVRdTNxUWd2S29TM21IT2V1clNwaXQxWXlsOD0=
<<< Decrypt...
cText: Br7vnGS+yj6VLksyuQu3qQgvKoS3mHOeurSpit1Yyl8=
cText: Hi this Is a test.
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = true **

 

[Erel]

The two getDecoded and getEncoded subs do not do anything useful.

What is the tablet version?

Try the project you've uploaded with a 24 byte key. Do you still get different results? Can you post them?

 

[vecino]

The two getDecoded and getEncoded subs do not do anything useful.

Hello, it's just to make the key more complicated.

What is the tablet version?

Samsung galaxy tab S SM-T805 (Android 6.0.1)

Try the project you've uploaded with a 24 byte key. Do you still get different results? Can you post them?

Now the result is the same, why?

I have changed this code:
kg.KeyFromBytes(bconv.StringToBytes("1234567890123456","ASCII"))
For this other code:
kg.KeyFromBytes(bconv.StringToBytes("123456789012345678901234","ASCII"))

What explanation does this have?

Logger connected to:  samsung SM-T805
--------- beginning of main
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
>>> Encrypt...
cText: Hi this Is a test.
cText: n51bXuh/fpUQy4S+dFr6EUOM6NQqQ50g
cText: bjUxYlh1aC9mcFVReTRTK2RGcjZFVU9NNk5RcVE1MGc=
<<< Decrypt...
cText: n51bXuh/fpUQy4S+dFr6EUOM6NQqQ50g
cText: Hi this Is a test.
** Activity (main) Resume **

Logger connected to:  unknown miTab LIVE
--------- beginning of /dev/log/main
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
>>> Encrypt...
cText: Hi this Is a test.
cText: n51bXuh/fpUQy4S+dFr6EUOM6NQqQ50g
cText: bjUxYlh1aC9mcFVReTRTK2RGcjZFVU9NNk5RcVE1MGc=
<<< Decrypt...
cText: n51bXuh/fpUQy4S+dFr6EUOM6NQqQ50g
cText: Hi this Is a test.
** Activity (main) Resume **

 

[Erel]

Hello, it's just to make the key more complicated.

It doesn't add any real complexity. Just makes the code a bit more complicated.

Now the result is the same, why?

The triple DES key size should be 16 or 24 bytes. Seems like 24 bytes is more common.
I guess that there is an issue with older versions of Android and 16 bytes keys with triple DES.

 

[vecino]

Thank you very much for your help