can not associate to AP when using macchanger

[cabadce]

I would like to 1) use macchanger to alter my MAC address, then 2) associate to my AP using iwconfig.

That sounds like:
1)
ifconfig wlan0 down
macchanger -a wlan0
ifconfig up

2)
iwconfig wlan0 essid "my essid" channel 1 #optional: set other properties
iwconfig wlan0 ap xx:xx:xx:xx:xx:xx #should associate here

The point is that I can associate to the AP only if I skip step 1), ie. if I don't use (GNU) macchanger.

Is this the expected behavior, or should the association still happen ?

TIA,
cabadce

[theprez98]

You might gather more responses if you post what type of card you're using; since that could impact your results.

[Snayler]

Have you tried "ifconfig <interface> hw <class> <address>" instead of using macchanger?

[cabadce]

Excuse me for the missing information.

The card is an Intel bgn:
03:00.0 Network controller: Intel Corporation Wireless WiFi Link 5100 #lspci output

As reported by lsmod, the driver in use is:
mac80211 210008 2 iwlagn,iwlcore

TIA,
cabadce

[Lincoln]

Also verify MAC address filtering isn't enabled on your AP.

[Takedown32]

i could not change the mac with macchanger or even do ifconfig wlan0 down if the network service was started before.Had to stop it and do all this again

[Whiskey]

Have you tried keeping the vendor (first six digits of mac) the same but altering the rest? I too agree with Lincoln too...check for mac address filtering

[foster]

You may try this:

ifconfig <interface> down
macchanger --mac <mac number> <interface>
ifconfig <interface> up

Or follow steps used to enable monitor mode in order to attack wifi networks.

There is a LOT of information on the forums....

[cabadce]

Thanks for all the proposed advises ... but I'm still unable to associate to the AP.

The network card is an Intel WiFI Link 5100 (sony vaio laptop), and the AP does not involve any security settings (open network, no WEP/WPA, no MAC filtering).
Using this configuration, I can not associate to the AP if I change the client MAC address, neither via macchanger nor ifconfig. An interesting point is that I can associate to the AP if I "change" the client MAC address to the same address, either via macchanger -m <my MAC> or ifconfig hw ether <my MAC>.

Related loaded modules are:
iwlagn 124896 0
iwlcore 133600 1 iwlagn
mac80211 210040 2 iwlagn,iwlcore
cfg80211 109144 3 iwlagn,iwlcore,mac80211
led_class 5256 2 iwlcore,sdhci

I can detail the testing I've done:
1) macchanger -a wlan0 ; iwconfig wlan0 up; iwconfig wlan0 essid <essid> channel <ch> ap <xx:xx:xx:xx:xx:xx>
2) macchanger -e wlan0 ; iwconfig wlan0 up; iwconfig wlan0 essid <essid> channel <ch> ap <xx:xx:xx:xx:xx:xx>
3) macchanger -m $MY_MAC_ADDRESS ; iwconfig wlan0 up; iwconfig wlan0 essid <essid> channel <ch> ap <xx:xx:xx:xx:xx:xx>
4) macchanger -m $ANOTHER_MAC_OF_SAME_KIND ; iwconfig wlan0 up; iwconfig wlan0 essid <essid> channel <ch> ap <xx:xx:xx:xx:xx:xx>
5) ifconfig wlan0 ether hw $MY_MAC_ADDRESS ; iwconfig wlan0 up; iwconfig wlan0 essid <essid> channel <ch> ap <xx:xx:xx:xx:xx:xx>
6) ifconfig wlan0 ether hw $ANOTHER_MAC_OF_SAME_KIND ; iwconfig wlan0 up; iwconfig wlan0 essid <essid> channel <ch> ap <xx:xx:xx:xx:xx:xx>

Before each test, I do some cleaning as:
/etc/init.d/networking stop
sleep 2
ifconfig wlan0 down
sleep 2
macchanger --mac $MY_MAC_ADDRESS wlan0


As previously stated, only 3) and 5) allow me to associate to the AP using iwconfig.

When I change to an address of the same kind, ie. 2),4), and 6), the syslog file shows:
Jan 19 19:16:09 bt kernel: Registered led device: iwl-phy0::radio
Jan 19 19:16:09 bt kernel: Registered led device: iwl-phy0::assoc
Jan 19 19:16:09 bt kernel: Registered led device: iwl-phy0::RX
Jan 19 19:16:09 bt kernel: Registered led device: iwl-phy0::TX
Jan 19 19:16:09 bt kernel: ADDRCONF(NETDEV_UP): wlan0: link is not ready
Jan 19 19:16:11 bt kernel: wlan0: direct probe to AP 00:1a:2b:49:d6:81 try 1
Jan 19 19:16:11 bt kernel: wlan0: direct probe to AP 00:1a:2b:49:d6:81 try 1
Jan 19 19:16:11 bt kernel: wlan0 direct probe responded
Jan 19 19:16:11 bt kernel: wlan0: authenticate with AP 00:1a:2b:49:d6:81
Jan 19 19:16:12 bt last message repeated 2 times
Jan 19 19:16:12 bt kernel: wlan0: authentication with AP 00:1a:2b:49:d6:81 timed out

When I change to an address of another kind, ie. 1), the syslog file shows:
Jan 19 19:11:17 bt kernel: Registered led device: iwl-phy0::radio
Jan 19 19:11:17 bt kernel: Registered led device: iwl-phy0::assoc
Jan 19 19:11:17 bt kernel: Registered led device: iwl-phy0::RX
Jan 19 19:11:17 bt kernel: Registered led device: iwl-phy0::TX
Jan 19 19:11:17 bt kernel: ADDRCONF(NETDEV_UP): wlan0: link is not ready
Jan 19 19:11:19 bt kernel: iwlagn 0000:03:00.0: Aborted scan still in progress after 100ms
Jan 19 19:11:19 bt kernel: wlan0: Failed to config new BSSID to the low-level driver
Jan 19 19:11:23 bt kernel: wlan0: authenticate with AP 00:1a:2b:49:d6:81
Jan 19 19:11:23 bt last message repeated 2 times
Jan 19 19:11:23 bt kernel: wlan0: authentication with AP 00:1a:2b:49:d6:81 timed out

When I "change" to the same address, ie. 3) and 5), the syslog file shows:
Jan 19 19:07:18 bt kernel: ADDRCONF(NETDEV_UP): wlan0: link is not ready
Jan 19 19:07:20 bt kernel: wlan0: direct probe to AP 00:1a:2b:49:d6:81 try 1
Jan 19 19:07:20 bt kernel: wlan0: direct probe to AP 00:1a:2b:49:d6:81 try 1
Jan 19 19:07:20 bt kernel: wlan0: direct probe to AP 00:1a:2b:49:d6:81 try 2
Jan 19 19:07:20 bt kernel: wlan0 direct probe responded
Jan 19 19:07:20 bt kernel: wlan0: authenticate with AP 00:1a:2b:49:d6:81
Jan 19 19:07:20 bt kernel: wlan0: authenticated
Jan 19 19:07:20 bt kernel: wlan0: associate with AP 00:1a:2b:49:d6:81
Jan 19 19:07:20 bt kernel: wlan0: RX AssocResp from 00:1a:2b:49:d6:81 (capab=0x401 status=0 aid=1)
Jan 19 19:07:20 bt kernel: wlan0: associated
Jan 19 19:07:20 bt kernel: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Jan 19 19:07:31 bt kernel: wlan0: no IPv6 routers present

Bellow are a few points I also think noticeable:
+ the interface wlan0/mon0 is usable in monitoring mode with aircrack-ng
+ the behavior is exactly the same as using a 64-bits Ubuntu 9.10 distribution with a 2.6.31-18 kernel

I would still be pleased with any additional comment or suggestion.

tia,
cabadce

[btuser]

Got the same issue.
Macchanger changes my MAC address when the device is down (shown on macchanger and ifconfig),
but when I start it, it sets the MAC address back to card's default.

Am I missing something?

Thanks!