Android Question Read \ Write NCF Midfare Clasic

[Situ LLC]

Greetings clever friends
My question is this
From the examples of writing and reading with the NFC library that are in the forum, I have seen many questions and problems with use.
I have an example that is partly functional. You can read sector 0 and block 0,1,2,3, until then perfect.
But if I try to read Sector 1 blocks 4,5,6,7 it is not successful, even though the key authentication is correct in both transactions.

Look . Try to read Sector =0 Block = 0

Techs: [android.nfc.tech.MifareClassic, android.nfc.tech.NfcA, android.nfc.tech.Ndef]
c7 63 d8 33
UUID ok
ID c7 63 d8 33
Connect: true

Block Read 0 success true Flag 0
Sector 0 Block 0 Result= c763d8334f0804006263646566676869
Success, even on block 01,2,3

\----------------------------------------------------------------------------------------/


Now i will try to read Sector 1, blocks 4

Techs: [android.nfc.tech.MifareClassic, android.nfc.tech.NfcA, android.nfc.tech.Ndef]
c7 63 d8 33
UUID ok
ID c7 63 d8 33
Connected: true
authentication del sector. Success=true, Flag=0

Sector =1 Block = 4 MSG

Block Read 4 Estado false Flag 0

cannot read

\------------------------------------------------------------------------------------------/

As you can see, the authentication is fine according to what can be seen, because it leaves only sector 0, the others
are not, the authentication is fine, I use a new 1K Midface card

In writing despite having successful sector authentication and the correct block number
Sector 0, block 1


The result


Techs: [android.nfc.tech.MifareClassic, android.nfc.tech.NfcA, android.nfc.tech.Ndef]
c7 63 d8 33
UUID ok
ID c7 63 d8 33
Connected: true
authentication del sector. Success=true, Flag=0
Sector =0 Block = 1
writing was = false, Flag=0
Write Error: null

I would like to know if anyone has already managed to overcome these problems and share the solution.
I am fully available to pay for help. Thank you



[CODE lang="b4x" title="Write \ Read Midafare clasic" highlight="MidFare Classi 1K"]#Region Project Attributes
#ApplicationLabel: NFC_SITULLC
#VersionCode: 1
#VersionName:
'SupportedOrientations possible values: unspecified, landscape or portrait.
#SupportedOrientations: unspecified
#CanInstallToExternalStorage: False
#End Region

#Region Activity Attributes
#FullScreen: False
#IncludeTitle: True
#End Region
Sub Process_Globals
Private prevIntent As Intent
Public sector As Int=0
Public Block As Int = 0
Private message As String =""
Private evento As Boolean

End Sub

Sub Globals
Private nfc As NFC
Private TagTech As TagTechnology
Private LeerBlock As Button
Private Escribir_block As Button
End Sub


Sub Activity_Create(FirstTime As Boolean)
Activity.LoadLayout("Layout")
evento= True ' try read\write
End Sub

Sub Activity_Resume
Try
nfc.EnableForegroundDispatch
Dim si As Intent = Activity.GetStartingIntent
If si.IsInitialized = False Or si = prevIntent Then Return
prevIntent = si
Dim tag As JavaObject
If si.Action.EndsWith("TECH_DISCOVERED") Or si.Action.EndsWith("NDEF_DISCOVERED") Or si.Action.EndsWith("TAG_DISCOVERED") Then
Dim techs As List = nfc.GetTechList(si)
Log($"Techs: ${techs}"$)

Dim Id0() As Byte
Dim Id(8) As String
Dim jTagTech As JavaObject
'NfcA
If techs.IndexOf("android.nfc.tech.NfcA")> -1 Then
TagTech.Initialize("TagTech", "android.nfc.tech.MifareClassic", si)
TagTech.Connect
jTagTech = TagTech

tag = jTagTech.RunMethod("getTag", Null)
Id0 = tag.RunMethod("getId", Null)

If Id0(0)>0 Or Id0(1)>0 Or Id0(2)>0 Or Id0(3)>0 Then

Id(0)= Right("0" & Bit.ToHexString(ToUnsigned(Id0(0))),2)
Id(1)= Right("0" & Bit.ToHexString(ToUnsigned(Id0(1))),2)
Id(2)= Right("0" & Bit.ToHexString(ToUnsigned(Id0(2))),2)
Id(3)= Right("0" & Bit.ToHexString(ToUnsigned(Id0(3))),2)

Log(Id(0)&" "&Id(1)&" "&Id(2)&" "&Id(3))
Log("UUID ok")
LogColor("Numero de tarjeta "& Id(0)&" "&Id(1)&" "&Id(2)&" "&Id(3),0xFF0F26FC)
Else
LogColor("Error en Serial de Tarjeta ",0xFFFF0000)
End If
Else
ToastMessageShow("Tag does not support Ndef.", True)
End If
End If
Catch
Log(LastException)
LogColor("Erro 1 "&LastException,0xFFFF0000)
End Try
End Sub


Private Sub TagTech_Connected (Success As Boolean)
LogColor($" Conectado : ${Success}"$,0xFF001FFF)

Dim key() As Byte = Array As Byte(0xA0,0xA1,0xA2,0xA3,0xA4,0xA5)

sector =0
Block =1

If Success = False Then
ToastMessageShow("Error connecting to tag", True)
Log(LastException)
Else

Try
TagTech.RunAsync("Authenticate", "authenticateSectorWithKeyA", Array(sector, key), 0)
Catch
ToastMessageShow("Ath1:"&LastException,False)
End Try

End If
End Sub

Private Sub Escribir_block_Click
End Sub

Private Sub Authenticate_RunAsync (Flag As Int, Success As Boolean, Result As Object)

Log($"Autenticacion del sector . Success=${Success}, Flag=${Flag}"$)

If Success Then

Log( "Sector ="& sector& " Block = "& Block & " MSG "&message)

Try

If evento Then

TagTech.RunAsync("readBlock0","readBlock", Array(Block), 0)

Else

TagTech.RunAsync("writeBlock", "writeBlock", Array(Block,message), 0)
End If

Catch
ToastMessageShow("Read2:"&LastException,False)
LogColor("Read2:"&LastException,0xFFFF0000)
End Try
Else
LogColor("Read error flag :"& Flag,0xFFFF0000)
End If
End Sub


Private Sub Authenticate1_RunAsync (Flag As Int, Success As Boolean, Result As Object)

Log($"Autenticacion del sector . Success=${Success}, Flag=${Flag}"$)
Block=2
If Success Then
Log( "Sector ="& sector& " Block = "& Block )
Try

TagTech.RunAsync("readBlock0","readBlock", Array(Block), 0)

Catch

ToastMessageShow("Read2:"&LastException,False)
LogColor("Read2:"&LastException,0xFFFF0000)

End Try
Else
LogColor("Read error flag :"& Flag,0xFFFF0000)
End If
End Sub

Private Sub Authenticate2_RunAsync (Flag As Int, Success As Boolean, Result As Object)

Log($"Autenticacion del sector . Success=${Success}, Flag=${Flag}"$)
Block=3
If Success Then
Log( "Sector ="& sector& " Block = "& Block )
Try
TagTech.RunAsync("readBlock0","readBlock", Array(Block), 0)

Catch
ToastMessageShow("Read2:"&LastException,False)
LogColor("Read2:"&LastException,0xFFFF0000)
End Try
Else
LogColor("Read error flag :"& Flag,0xFFFF0000)
End If
End Sub





Private Sub writeBlock_RunAsync (Flag As Int, Success As Boolean, Result As Object)
LogColor($"Escritura de block fue =${Success}, Flag=${Flag}"$,0xFF0037FF)

If Success Then
LogColor("Escritura ok : "&Result ,0xFF0037FF)
Else
LogColor("Escritura Error : "&Result ,0xFFFF0000)


End If
End Sub





Private Sub readBlock0_RunAsync(Flag As Int, Success As Boolean, Result As Object)

LogColor("Block Read "&Block & " Estado "&Success &" Flag "&Flag ,0xFF0037FF)


' Log(LastException)

If Success Then
If Result<>Null Then
Dim myBlock() As Byte = Result
Dim sb As StringBuilder
sb.Initialize
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(0))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(1))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(2))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(3))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(4))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(5))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(6))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(7))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(8))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(9))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(10))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(11))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(12))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(13))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(14))),2))
sb.Append(Right("0" & Bit.ToHexString(ToUnsigned(myBlock(15))),2))

Log("Contenido Sector "&sector &" Block "& Block &" " &sb)

TagTech.Close ' important'

End If
Else
Log("cannot read")
End If
End Sub




Sub Activity_Pause (UserClosed As Boolean)
nfc.DisableForegroundDispatch
End Sub

Sub ToUnsigned(b As Byte) As Int
Dim x As String
x= Bit.And(0xFF, b)
Return x
End Sub

Sub Right(Text As String, Length As Int) As String
If Length>Text.Length Then Length=Text.Length
Return Text.SubString(Text.Length-Length)
End Sub

\------------------------------------------------------------------------------------------



I would like to know if anyone has already managed to overcome these problems and share the solution.
I am fully available to pay for help.
Thank you


[/CODE]

 

[drgottjr]

i had a little difficulty followng your description, but it looks like you're trying to write to sector 0. if that's what you're doing, you can't. it's protected.

 

[Situ LLC]

Thanks for responding.

I am really clear about the restrictions of each of the blocks.
What I want to explain is that sector 0 is possible to read blocks 0,1,2,3

The problem is when changing Sector 1 and reading blocks 4,5,6,7 already gives an error.

Validation and authentication are correct in any sector,
I know the restrictions on Midfare cards, it's just that these examples don't work correctly.

The Midfare card es new.
Thanks

 

[drgottjr]

at no point in the code that you posted do you refer to sector as anything but 0. hence my inference that you were trying to write to sector 0. but it sounds like you know all there is to know, so i'm sure you'll resolve things.

 

[Situ LLC]

I think you misunderstand.

I said I know the restrictions on midfare cards
and if you see I said I can read sector 0 block 0,1,2,3, but if I change sectors and appears that it is authorized and authenticated .
it does not read the content of sector 1 in terms of showing the content of blocks 4, 5,6,7

About r writing, I try to write sector 0, block 1, which has no restriction.

FOR REASON, I ASK, could it be a problem with the library, or with the way they are using the method calls?

Thanks for your appreciation