Write data to NTAG213 - ios

Hi in my iOS app I'm trying to use the ACR1255U, I want to write to a NTAG213 card some data,I found a way by using APDU command. I found a list of APDU command here, so the command to update binary for ACR1255U it's the follow:
FF D6 00 P1 Lc DATA (P1 --> starting block to update, Lc --> number of bytes)
so for example if I want to write A003, I generate the following NSString:
FF D6 00 04 04 41 30 30 33
but sometimes when I try to write it to a card it works perfectly and sometimes it fails, but I've no idea why... The command is correct and I'm using the SDK inserted in demo app that I download from here.
Does anyone has an idea about why sometimes it works and sometimes it doesn't work?
Thank you
It happen in the demo app and in my app

Related

Finding the documentation for parsing data found in BLE Advertising Respones

This is not a programming related question. It's a question about where to find the right documentation.
If this is not the right place to ask, please let me know and I'll move the question
I'm working on a C++-Deamon for parsing recieved BLE Advertising Packages (like hcidump from bleuz). For this I'm focusing on parsing only LE Advertising Report events (Bluetooth Core Specification 7.7.65.2, S. 2382 ff)
E. g: I need to extract the local name and the 16-bit UUID. This information can be found (if broadcasted) in the field "data".
I can extract the data part from the Advertising Event Packet (since it's described in the Core Specification how these packages are arranged) but I can't parse the data. I wasn't able to find a description of the codes used in this data frame.
I also went through the Core Specification Supplement, but I couldn’t find the corresponding codes. I only found some examples:
See Site 26: Apparently the byte 0x09 indicates that the following n bytes are the broadcasted name of the BLE-Device.
Or Site 25: 0x03 seems to indicate that a "Complete list of 16-bit Service UUIDs" is following.
So far I gained my knowledge about this by just going throught these (incomplete) list of examples I found and from looking at the source code of hcidump.c.
Now the question is: Where can I find the official complete list to those bytes/codes?
Just an example of the package content I revieve:
Respone: 04 3E 1C 02 01 04 01 55 19 19 E4 8D FE 10 0F 09 54 65 73 74
20 49 50 53 50 20 6E 6F 64 65 C5
It should be able to extract the following data
HCI Event: LE Meta Event (0x3e) plen 28
LE Advertising Report
SCAN_RSP - Scan Response (4)
bdaddr FE:8D:E4:19:19:55 (Random)
Complete local name: 'Test IPSP node'
RSSI: -61
After going throught the whole Bluetooth SIG, I finally found the site where these codes are described:
https://www.bluetooth.com/specifications/assigned-numbers/generic-access-profile/

FAST_READ with ACR1255U

I'm currently using this NFC reader ACR1255 to reads NTAG213 with an text ndef on it on an iOS app
I'm currently doing 2 read commands for 16 bytes each (because i know the size of my ndef message) but i find it not really reliable
While reading the NTAG213 doc I found the FAST_READ command but I can't seem to use it ?
I'm kinda new at NFC and it's a pretty mess for me I'm not sure i'm doing something wrong ?
For the moment i'm sending this apdu to read: "FF B0 00 04 10" and "FF B0 00 04 10" and concat the result and I got my ndef message
But for the FAST_READ I try this : "FF 3A 04 00 00" and I receive "6A 81" for function not supported.
Is there a protocol compatibily I didn't see ? Or someone has an idea ?
Seems like your end index is incorrect, it should be 4 or more.
Working example.

What is this most likely if not Lua bytecode?

I considered posting this in reverse engineering but because of the brevity of the question and general irrelevance I decided to post it here.
This may be a really easy question but I haven't been able to find an answer - I should probably read a bit of Lua's source before asking this, but here goes: in a program that has integrated Lua, this is the first few bytes of the buffer being executed:
11 16 A5 F1 9E A8 8B 64 78 8E 2F EA 1C 31 D3 B6 D3 D5 77 23 77 79 1B 73
I've never understood Lua very well, but that doesn't look like byte code. Is there anything else it could be or is it just certainly something custom? I'm pretty sure actual Lua opcodes haven't been modified.
if possible put whole file somewhere. Lua bytecode usualy starts with 1B 4C 75 61 and then some debug infos however there are zeros for spliting of the informations which your sample doesnt have
other way is asking on http://forum.xentax.com/
Put this into a file and try running luac -l filename on it. This will disassemble the binary to the VM instructions.
If it is Lua code you'll get some meaningful output.

Unexpected binary sequences in Postscript generated by Canon printer driver

We are having issues with the Postscript code generated by the "Canon iR-ADV C5235/5240 PS3" printer driver. We print a test document (3 A4 pages of Lorem Ipsum text) and get the following Postscript output in the Windows spool directory:
http://files.etvdzs.info/original.ps
We have tried various Postscript viewers/converters, and they are unable to handle this file. The reason is that the file contains sections of binary data at the beginning and end, and also the following byte sequence at position 0x1060b:
cd ca 10 02 00 1a 00 01 82 6f ff ff 00 00 00 00 00 00 00 00 01
If we remove these three binary sequences, we get the resulting file, which works fine in most Postscript viewers/converters we have tried:
http://files.etvdzs.info/cleaned.ps
Has anybody else encountered similar issues with Canon printer drivers? Does anybody know what these binary sequences signify, or what format they are in?
The binary sequences are CPCA codes. One can download documentation about the data structures used in CPCA after registering here:
https://www.developersupport.canon.com/user/register
It is then reasonably straightforward to write a program that strips the CPCA codes out of the file. The file can then be loaded successfully by 3rd-party Postscript viewers/converters.

What format is this string in? [closed]

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.
Closed 10 years ago.
I'm trying to figure out what data an iPhone game app is sending. It uses the GKTurnBasedMatch framework.
I've captured some of its packets and I found a promising XML message with this string as the value for a game-state key:
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
Base64, of course! So I decoded it and got:
{"GameGuid":"bd120afb-3c64-4e76-937a-fe1628e1db57","GameData":"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"}
Looks like a dict with another Base64 string in the GameData key. However, Base64 decoding that gives me a bunch of binary data:
02 01 14 c2 a9 69 f2 22 d1 bd 5c 10 7d 6f 96 b4 .....i."..\.}o..
e1 e2 9c 55 a3 51 ac 6d e7 5c a5 dc c2 c2 37 6c ...U.Q.m.\....7l
3e 2e 07 7d 89 23 b1 6d 11 6f bf 0e a0 da e4 ab >..}.#.m.o......
d9 18 17 4d cc aa 73 d6 17 b9 f7 55 15 ed 60 b9 ...M..s....U..`.
which is uncompressible:
>>> len(game_data)
4114
>>> len(game_data.encode("zlib"))
4125
It's not zlib-encoded:
>>> game_data.decode("zlib")
Traceback (most recent call last):
File "<pyshell#126>", line 1, in <module>
game_data.decode("zlib")
File "C:\Python27\lib\encodings\zlib_codec.py", line 43, in zlib_decode
output = zlib.decompress(input)
error: Error -3 while decompressing data: incorrect header check
And it's not even zlib without the header:
>>> def inflate(data):
import zlib
decompress = zlib.decompressobj(
-zlib.MAX_WBITS # see above
)
inflated = decompress.decompress(data)
inflated += decompress.flush()
return inflated
>>> inflate("roflcopters".encode("zlib")[2:])
'roflcopters'
>>> inflate(game_data)
Traceback (most recent call last):
File "<pyshell#130>", line 1, in <module>
inflate(game_data)
File "<pyshell#128>", line 6, in inflate
inflated = decompress.decompress(data)
error: Error -3 while decompressing: invalid distance too far back
I've tried using this online Objective-C compiler along with various classes like NSUnarchiver, NSKeyedUnarchiver, and NSPropertyListSerialization, but no luck, yet. Those all seem to produce output which at least has recognizable strings in it so even if they are used, something else must be going on as well.
The only similarity between different batches has been that they all start with 0x0201. Everything else seems totally different, even for subsequent updates for the same match, which makes me wonder if there's some obfuscation/encryption going on...
Any tips on where I can go from here?
It's almost certainly some proprietary structure from within the game, serialized out to bytes. 0x0201 could well be versioning for a struct, or just a set of flags that doesn't change across blobs you've seen.
There's no need to assume this is intentionally obfuscated or encrypted data. Standard textual (JSON, XML) and binary (bplist) containers are increasingly ubiquitous and often make one's life easier, but there's nothing nefarious about representing data in a more raw binary format if it's convenient. (See below re: encryption)
To really reverse engineer this in any more detail may be a Sisyphean task: figure out what the values in the binary blob are, numerically or otherwise. Match up the game state data with known (or unknown) values for the game. Do reverse engineering on the code to see what it's writing. That's some varsity stuff, but it's possible.
Re: encryption: encryption, or at least signing, is common in some parts of online gaming to prevent tampering with game state by bots to gain advantage. Whether that's happening here or not is anyone's guess. A bunch of floating point numbers that represent world positions could look similarly random.

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