Sign-In App & Net2 Proximity Cards

[smarties11]

Hi All,

 

We've recently purchased Sign-In App visitor management system, including the 'app-tap' proximity reader. It's all working really well in my testing.

 

However, one pitfall I've come across is with the enrolment of our existing Net2 proximity cards. I had expected to be able to export the Net2 token codes from Net2 and then transfer them into Sign-In App. Unfortunately this doesn't work, as the code stored in Net2 is different to the code that is read by app-tap.

 

For example, in Net2 I see a card code of 55263203; if I transfer this into Sign-In App and then use app-tap, it doesn't recognise my card. If I enrol the same card into Sign-In App, the code for the card is 80415818 - and then it works.

 

I've contacted their support and they say the Net2 codes are encrypted and cannot be converted.

 

I just wondered whether this was the 'final word' or whether anyone had any luck? I see some posts on here about converting the Net2 codes to a longer format for use with PaperCut, but in this case both codes are 8 digit.

 

Just trying to avoid staff manually enrolling.

 

Thanks

[nwkeene]

We had a similar issue when we tried to get our mifare cards to work on Biostore and our Paxton door readers...

 

We found a conversion formula and used excel to convert. We used the 'DEC2HEX and after a shuffle, HEX2DEC to give us a number. Its to do with little endian and big endian numbers i think and how the numbers are read in HEX. My spreadsheet doesn't work on your numbers however... Its finding the pattern in HEX that seems to be the trick.

This mifare site has some useful info...

my2p

[mavhc]

Sounds like the amount of encryption to expect from net2

 

However also remember that it's just binary data, how is it represented, 4 bits per number in base 10, or a 64 bit binary number? What endian? 100 different ways of doing it

 

It'll be the same bits interpreted in a different way

[smarties11]

I think I've reached the limits of my knowledge on this one.....I've tried converting both to HEX and there is no pattern with swapping the bits round. I've set the app-tap to read in Hex, Dec, Dec10 and Net2 formats and compared those values both decimal and Hex. I've converted Net2 and the codes returned by app-tap to binary and then overlaid them to look for a pattern (nothing). I've tried little->big endian conversions and again nothing obvious :-(

[Chris_Cook]

Net2 doesn't use all the bits from the serial number, and the other system may not either.

 

The other issue is if you are using HID readers, or Paxton readers, as they can read back to front as well.

 

Have you got the card IDs in hex format from papercut or AD? The hex number is usually complete, so you can do the conversion if you have that. But once the bits have been stripped you can't get them back.

 

For our HID readers, its something like the least significant 55 bits from the hex number you need. You lose a byte and 1 bit or the left most hex character and part of the second one.

 

When you reverse the number, you have to reverse the hex number, but in bytes or pairs - so A1B2C3D4 becomes D4C3B2A1

 

I have a google apps script that does the conversions for me in a google sheet, and I think salamander can pull them out of AD into Net2.

Edited July 14, 2022 by Chris_Cook

[steveg]

Did you ever get anywhere with this? We have Net2 cards and sign in app now, and as you say the numbers that they scan in no way relate to each other. Currently getting staff to manually enroll.

 

I did speak to paxton and they confirmed that they don't encrypt it, so it must just be it reading a different part of the number or storing it differently.

[smarties11]

Did you ever get anywhere with this? We have Net2 cards and sign in app now, and as you say the numbers that they scan in no way relate to each other. Currently getting staff to manually enroll.

 

I did speak to paxton and they confirmed that they don't encrypt it, so it must just be it reading a different part of the number or storing it differently.

 

Nope, spent hours researching it and then just got staff to enrol manually 😆

[mavhc]

Made a list of the binary representations of the same fobs on the two systems and look for patterns

[Steve21]

Did you ever get anywhere with this? We have Net2 cards and sign in app now, and as you say the numbers that they scan in no way relate to each other. Currently getting staff to manually enroll.

 

I did speak to paxton and they confirmed that they don't encrypt it, so it must just be it reading a different part of the number or storing it differently.

 

You got an example from both systems? I made a spreadsheet to convert the most common ones at a previous job, so I could see if any of them match one of the common formulas.

 

Steve

[steveg]

You got an example from both systems? I made a spreadsheet to convert the most common ones at a previous job, so I could see if any of them match one of the common formulas.

 

Steve

 

Thanks, I've just added a couple of different ones to my account for testing, a newer card and an old fob, not that it should make a difference what they are. Sign in app is set to net2 mode.

 

Card

Paxton number 45968389

Signinapp number 20012943

 

Fob

Paxton number 86500002

Signinapp number 04414821

[Chris_Cook]

Have you got a phone with an RFID or NFC reader on it? You can get an app that will let you read the card serial number in Hex. It can then be converted with a spreadsheet formula or windows calculator in programmers mode.

 

You won't reliably be able to convert the numbers as part of it is missing in both paxton and Signinapp formats. You might get lucky if all your cards are from the same batch as part of the CSN is the same for each batch of cards.

 

Unless you can scan the number into an existing system in hex format (like say Papercut), its probably easiest to just scan the cards twice. You can get usb card readers that spit out the necessary hex code, but you then have to copy and paste it in every where.

 

Another thought I just had is what card readers are you using with Net2? Are they the paxton one, or HID readers? Can you take one off the wall and look at the part number? Should be a screw underneath the reader to release it. Paxton readers have 3 lights, HID normally have 1 bar across the bottom.

[Scifigirl]

we have a spread sheet that converts the card read by the scanner for sharp printers and papercut and converts it to NET 2-- happy to send a copy if any help

 

we use mifare classic cards,

.

[steveg]

Thanks, have dropped you a pm for the spreadsheet. I suspect it wont work, but would be good to try. I think from what i've read and what others are saying on here, the cards actual have a 26(?) digit number encoded in them, but paxton only uses 8 numbers from it. If the reader that signinapp uses uses a different 8 digits then there wont be a way to convert between them.

[mavhc]

Unless you get all 26 numbers via a standalone scanner

 

What's the formula for the spreadsheet? Might as well put it here for future use

[Chris_Cook]

This is the google apps script I use with google sheets, hope it helps.

 

function hex2paxton_SN(hex) 
{
 if ( hex && hex != "") {
   return parseInt(parseInt(hex, 16).toString().substr(-8, 8)).toString();
 }
}

/// convert an 8 character hexadecimal number (string) to the HID format.
//
// Process:
// 1. Reverse the bytes
// 2. take the right most (Least significant) 27 bits
// 3. convert to decimal
// 4. limit to right most 8 chars.

function hex2HID_SN(hex) 
{
 if (hex && (typeof(hex) == "number") && hex != 0 )  {    hex = hex.toString();   } 

 if (hex && (typeof(hex) == "string") && hex != "")
 {
   var hex_reversed = hex.substr(7, 1) + hex.substr(4, 2) + hex.substr(2, 2) + hex.substr(0, 2);

   var bit_mask = 0x07FFFFFF;

   var final_number = bit_mask & parseInt(hex_reversed, 16);

   return final_number.toString().substr(-8, 8);
 } else {
   return "";
 }

}

[Scifigirl]

What's the formula for the spreadsheet? Might as well put it here for future use

 

I pulled it from another thread (that I can't now find)but:

1. Mifare card number

2: =DEC2HEX of MIFARE

3: =MID(D3,7,2)&MID(D3,5,2)&MID(D3,3,2)&MID(D3,1,2) D is the DEX to HEX column

4:=HEX2DEC(E3) E is the above column

5: =RIGHT(F3,8) F is the above column.

[Edu-IT]

Did you every get anywhere with this or did you give up?

[mrbios]

1 hour ago, Edu-IT said:

Did you every get anywhere with this or did you give up?

Sign in app have an option to read "net2" as a format these days. On the setup they can read 10 digit dec, 8 digit dec, hex or net2. 

 

I got sign in app tap this summer and i'm using the number read by Net2, plonking that in to an AD field and papercut and sign in app are using that same number. Only downside is the need to manually put the card numbers into AD after scanning them to net2, but at least the number is the same everywhere, no need to convert anything.

[nathan3388]

On 30/03/2023 at 09:47, Scifigirl said:

we have a spread sheet that converts the card read by the scanner for sharp printers and papercut and converts it to NET 2-- happy to send a copy if any help

 

we use mifare classic cards,

.

Hi, 

 

Do you have the spreadsheet to hand so that we can try to get the numbers working in the sign in app that we have?so that we can convert the numbers to hex?

 

Thanks

 

Nathan

[AlphamaleZed]

Do they not offer a NET2 Connector?

Edited March 4 by AlphamaleZed

[AlphamaleZed]

Do they not offer a NET2 Connector?