NFCTOOL(1)

💖 NFCTOOL(1) 💖

okay bestie, welcome to the nfctool page, straight outta the General Commands Manual. she's a little NFC toolbox and she's lowkey iconic 💅

✨ NAME ✨

nfctool — a NFC toolbox 🧰

🌸 SYNOPSIS 🌸

nfctool [OPTIONS...]

🦋 DESCRIPTION 🦋

so the nfctool application does a whole bunch of operations on NFC devices, like fr fr:

• list connected devices
• put device in polling mode
• get and set parameters for the local LLC
• send service name lookup request to the remote LLC.
• dump LLCP link traffic

main character energy tbh 👑

💅 OPTIONS 💅

• -h, --help — prints out nfctool's available options and then dips. that's it, that's the whole vibe.
• -v, --version — prints nfctool's version and exits. short and sweet.
• -l, --list — lists the attached NFC devices. it also prints info like remote tags or devices, supported protocols, RF mode, and LLC link parameters. like a full rundown, no crumbs left 🍓
• -d, --device=NFCDEV — specify a nfc device (i.e. nfc0). this one is mandatory for every single operation except -l. no cap.
• -p, --poll[=MODE] — starts a poll on the device you specified with -d. MODE has to be one of Initiator, Target, or Both, and it defaults to Initiator when you don't specify it. passing MODE as i, t, or b for respectively Initiator, Target, or Both is also accepted. so many options, we love that for us ✨
• -s, --set-param=PARAM=VAL[,PARAM=VAL[,...]] — sets LLC link parameters. PARAM must be at least one of:
  • lto=0..255 — Link TimeOut
    • specify the maximum time interval between the last received LLC PDU from the remote to the local LLC and the first subsequent LLC PDU transmission from the local to the remote LLC. the value is expressed in multiples of 10 milliseconds and is encoded as a 8-bit unsigned integer.
    • the LTO parameter must be set before the LLC Link is established. like, before, bestie, not after 🙈
  • rw=0..15 — Receive Window size
    • specify the maximum number of I PDUs the local LLC will accept before acknowledging them. a RW size of zero means the local LLC will not accept I PDUs on that data link connection. a RW size of one means the local LLC will acknowledge every I PDU before accepting additional I PDUs. it's encoded as a 4-bit unsigned integer.
    • the RW parameter can be set after the LLC Link is established. the new value will apply for subsequent connections.
  • miux=0..2047 — Maximum Information Unit Extension
    • specify the number of octets by which a LLC PDU information field may exceed the default maximum size of 128 octets. in other words, MIU = MIUX + 128. it's encoded as an 11-bit unsigned integer.
    • the MIUX parameter can be set after the LLC Link is established. the new value will apply for subsequent connections.
• -k, --snl=URN — sends a Service Name Lookup request for URN (i.e. urn:nfc:sn:snep) to the remote LLC. obviously the LLC link has to be up before the request gets sent, iykyk.
  • the remote should reply by returning the service access point (SAP) number, or zero if it doesn't support the requested service.
  • > Note: if you use this with -p, nfctool will wait for the LLC link to be up before sending the SNL request. patient queen 💖
• -n, --sniff — starts LLCP sniffing on the device specified with the -d option.

🎀 SNIFFER SPECIFIC OPTIONS 🎀

the following options only apply with -n. just those ones, bestie, don't get it twisted.

• -a, --snapshot-len=SNAPLEN — capture SNAPLEN bytes from each packet. default snapshot length is 1024 bytes.
• -y, --dump-symm — dump SYMM packets to stdout. this will generate a LOT of output. like, a LOT 😭
  • > Note: the -y option concerns console output only. SYMM packets are always dumped to the pcap file when specified by -f (see below). always always.
• -t, --show-timestamp[=MODE] — show packet timestamps. setting MODE as delta means the time since the first captured frame. absolute means elapsed time since the Epoch, 1970-01-01 00:00:00 +0000 (UTC). MODE defaults to delta when unspecified.
• -f, --pcap-file=FILENAME — specify a filename to save dumped traffic in pcap format. the generated file can be opened with Wireshark (http://www.wireshark.org/) using the wireshark-nfc plug-in available at http://code.google.com/p/wireshark-nfc/ 🌈

👑 SEE ALSO 👑

• neard (8)
• neard.conf (5)
• Linux NFC project page at https://01.org/linux-nfc/

and that's the whole page, periodt 💜 this was the nfctool manual from February 2013 (the General Commands Manual version) — thanks for reading bestie, go sniff some LLCP traffic for me 🦋✨