printpacket(packet);
sys.stdout.flush();
-class AddressGuesser():
+class AutoTuner():
"""This guesses addresses by searching through packets."""
- #packets=[];
addresses={};
- def packetaddr(self,packet):
- s="";
+ client=None;
+
+ #Limits on search space, because you usually know what you're looking for.
+ rate=False;
+ chan=False;
+ sync=False;
+ def init(self,goodfet,
+ rate=True,chan=True,sync=True):
+ """Initializes a link to the GoodFET for autotuning."""
+ self.client=goodfet;
+ self.rate=rate;
+ self.chan=chan;
+ self.sync=sync;
+ return;
+ def packetaddr(self,packet,justmac=False):
+ """Returns a loaded packet address, including channel and rate."""
+
+ sync=self.client.RF_getsmac()&0xFF;
+
+ mac="";
+ #MAC,RF_CH,RATE
for i in range(0,5):
- s="%s%02x" % (s,ord(packet[i]));
- return s;
+ mac="%s%02x" % (mac,ord(packet[i]));
+ if justmac:
+ return mac;
+ ch=self.client.peek(0x05);
+ rate=self.client.peek(0x06);
+ return "%02x,%s,%02x,%02x" % (
+ sync,mac,ch,rate);
+ def validmac(self,packet):
+ sync=self.client.RF_getsmac()&0xFF;
+ mac=self.packetaddr(packet,justmac=True);
+ if (ord(packet[0])&0x80)^(sync&0x80):
+ #print "%02x%02x invalid entry." % (sync,ord(packet[0]));
+ return False;
+ if mac=='5555555555' or mac=='aaaaaaaaaa':
+ return False;
+ return True;
+
def handle(self,packet):
+ """Handles a packet."""
#printpacket(packet);
- #self.packets.append(packet);
+ if not self.validmac(packet):
+ #print "Dropped packet:";
+ #printpacket(packet);
+ return;
addr=self.packetaddr(packet);
- #Increment the address.
+ #Increment the address count.
count=0;
try:
count=self.addresses[addr];
pass;
self.addresses[addr]=count+1;
rate=count*1.0/len(self.addresses);
- if self.addresses[addr]>1:
- print "'%s' looks valid, %0.5f" % (
- addr,rate);
+ if self.addresses[addr]>1 or rate>0.01:
+ print "'%s' looks valid\t%i\t%0.5f" % (
+ addr,count,rate);
+ return;
+ tunecount=0;
+ def retune(self):
+ """Tunes to another channel or preamble looking for the next packet."""
+ count=self.tunecount;
+ self.tunecount=count+1;
+
+ #Swap the SYNC value most often.
+ if self.sync:
+ sync=0xAA;
+ if count&1:
+ sync=0x55;
+ self.client.RF_setsmac(sync);
+ count=(count>>1);
+
+ if self.rate:
+ #Then the data rate.
+ rate=0;
+
+ #This swaps between 1Mbps and 2Mbps.
+ #TODO add support for 256kbps, if anyone uses it.
+ if count&1:
+ rate=rate|0x08;
+ #print "Setting rate to 0x%02x" % rate;
+ if(rate==0x20):
+ rate=0x08;
+ self.client.poke(0x06,rate);
+ count=(count>>1);
+
+ if self.chan:
+ self.client.poke(0x05,
+ (count+16)&0x7f);
+ print "Tuned to %i MHz" % (
+ self.client.RF_getfreq()
+ /(10**6));
+ #Grab two packets to clear buffers.
+ #Should retune only after a few packets to reduce this delay.
+ packet=client.RF_rxpacket();
+ packet=client.RF_rxpacket();
return;
+
if(sys.argv[1]=="autotune"):
#Reversal of transmitter code from nRF_CMD.c of OpenBeacon
#TODO remove all poke() calls.
- guesser=AddressGuesser();
+ guesser=AutoTuner();
+ guesser.init(client,rate=True,sync=True,chan=True);
client.poke(0x00,0x00); #Stop nRF
client.poke(0x01,0x00); #Disable Shockburst
client.poke(0x02,0x01); #Set RX Pipe 0
#client.RF_setfreq(2481 * 10**6);
- #client.poke(0x06,0x09); #2MBps, -18dBm in RF_SETUP
+ client.poke(0x06,0x09); #2MBps, -18dBm in RF_SETUP
client.poke(0x07,0x78); #Reset status register
#OpenBeacon defines these in little endian as follows.
client.RF_setmaclen(2); # SETUP_AW for shortest
- #It's better to have a known fragment, when one is available.
+ #This is determined by the MAC, which we don't yet know.
+ #AutoTuner() takes care of finding it.
#client.RF_setsmac(0x00AA);
#client.RF_setsmac(0x0055);
- #Should end in 55 or AA depending upon the packet.
- tail=0x55
- if(len(sys.argv)>2):
- tail=int(sys.argv[2],16);
- else:
- print "Please specify a tail of 0xAA or 0x55.";
- sys.exit(1);
- client.RF_setsmac(tail);
-
#Longest length.
client.RF_setpacketlen(32);
#Power radio, prime for RX, no checksum
client.poke(0x00,0x70|0x03); #0x08 for checksum, 0x04 for two.
- print "Listening as %010x on %i MHz" % (client.RF_getsmac(),
+ print "Autotuning as %010x on %i MHz" % (client.RF_getsmac(),
client.RF_getfreq()/10**6);
+ print "sync,mac,r5,r6";
#Now we're ready to get packets.
while 1:
- packet=None;
- while packet==None:
- packet=client.RF_rxpacket();
- guesser.handle(packet);
+ #Full second on each packet.
+ start=time.mktime(time.localtime());
+ while (time.mktime(time.localtime())-start) < 5:
+ packet=None;
+ while packet==None:
+ packet=client.RF_rxpacket();
+ guesser.handle(packet);
+ #print "Retuning."
+ guesser.retune();
sys.stdout.flush();
if(sys.argv[1]=="sniffmskb"):
#Other keyboards will be different.
- client.RF_setmaclen(2);
+ client.RF_setmaclen(5);
#Known pairs. The channel and the low address bytes must match.
#client.RF_setfreq((2400+0x13) * 10**6);
#client.poke(0x00,0x00); #Stop nRF
client.poke(0x07,0x78); #Reset status register
- #Power radio, prime for RX, checksum.
- client.poke(0x00,0x70|0x03|0x08);
+ #Power radio, prime for RX, no checksum.
+ client.poke(0x00,0x70|0x03);
+ #Mac packet length.
+ client.RF_setpacketlen(32);
+ #Mac length, reduced
+ client.RF_setmaclen(3); # SETUP_AW for shortest
print "Listening as %010x on %i MHz" % (client.RF_getsmac(),
client.RF_getfreq()/10**6);
projects / goodfet / blobdiff