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Hi, <br>
<br>
Not sure how to present this but I have been looking at this for acouple
of days now on and <br>
off. <br>
<br>
Configuration: <br>
Wireless PC (kauai) ---- 802.11 w/Wep key ----- wlan0- Hostap bridging-eth0
----- Linux machine (Molokai) <br>
<br>
I also replaced Kauai with a different pc and an imbedded wireless card same
fingerprint as below. <br>
<br>
The issue is I cannot do a ftp from my wireless PC (kauai) to the Linux machine
(Molokai) and do a put <br>
or i cannot FTP from molokai to the PC and do a get. (The FTP hangs - packet
get corrupted) <br>
<br>
I think it has to do with buffer allocation or a MTU gets broken because
if I reduce the MTU the problem goes away. <br>
If you notice the Packet size on the AP it is bigger than 1514 it is 1522
but only 96 gets captured. <br>
And if you look at the packet traces (Attached below) the payload gets truncated
at the AP side. <br>
The length of the ftp payload leaving kauai is 1448 bytes and the payload
on the AP side is only <br>
30 bytes (Rest of packet is lost). Molokai never sees this packet on it's
ethereal capture. <br>
<br>
This issue only occurs when I have the combination of WEP key, Hostap(DWL-650),
and Bridging. <br>
This issue goes away if I do ANY of the following: <br>
- I turn off WEP (iwconfig wlan0 enc off on ap and turn off wep security
on kauai) <br>
- I remove bridging and do routing though the hostap machine. <br>
- reduce my MTU (this is why I think it is overloading a buffer somewhere)
<br>
- use Hermes_ap (with Orinoco card of course) <br>
<br>
I have to tell you that I think the work done here has been fabulous you
have put <br>
together a great package and I love it.. I am getting by because I lowered
my MTU <br>
and things work great in that mode, but I thought i would put out this finding
to help the <br>
cause. <br>
Software: <br>
hostap-0.0.1.tar.gz <br>
Redhat kernel - 2.4.20 <br>
pcmcia-cs-3.2.4.tar.gz <br>
wireless_tools.25.tar.gz <br>
<br>
Hardware: <br>
Socket 0: <br>
product info: "D", "Link DWL-650 11Mbps WLAN Card", "Version 01.02", "" <br>
manfid: 0x0156, 0x0002 <br>
function: 6 (network) <br>
Socket 1: <br>
product info: "NETGEAR", "FA410TX", "Fast Ethernet" <br>
manfid: 0x0149, 0x0230 <br>
function: 6 (network) <br>
<br>
Gateway Solo 75Mhz Pentuim <br>
<br>
[root@solo wlan]# iwconfig wlan0 <br>
wlan0 IEEE 802.11b ESSID:"OmsNet" Nickname:"solo" <br>
Mode:Master Frequency:2.422GHz Access Point: 00:05:5D:EE:73:0F
Bit Rate:2Mb/s Tx-Power:-1 dBm Sensitivity=1/3 Retry
min limit:8 RTS thr:off Fragment thr:off <br>
Encryption key:3131-3131-31 Encryption mode:restricted <br>
Power Management:off <br>
Link Quality:0 Signal level:0 Noise level:0 <br>
Rx invalid nwid:0 Rx invalid crypt:838 Rx invalid frag:0 <br>
Tx excessive retries:915 Invalid misc:208 Missed beacon:0 <br>
<br>
<br>
Thanks for listening <br>
Let me know if there is any other data you would like to see of have me test
<br>
if you think it would help. <br>
<br>
Jeff Omick <br>
<a class="moz-txt-link-abbreviated"
href="mailto:jomick@users.sourceforge.net">jomick@users.sourceforge.net</a>
<br>
<br>
<br>
-------------------------------------------- <br>
Packet trace at Kauai side. <br>
<br>
Frame 27 (1514 on wire, 1514 captured) <br>
Arrival Time: Apr 25, 2003 19:00:38.125355000 <br>
Time delta from previous packet: 0.004764000 seconds <br>
Time relative to first packet: 13.465361000 seconds <br>
Frame Number: 27 <br>
Packet Length: 1514 bytes <br>
Capture Length: 1514 bytes <br>
Ethernet II <br>
Destination: 00:04:5a:72:e0:62 (The_72:e0:62) <br>
Source: 00:60:1d:04:78:54 (Lucent_04:78:54) <br>
Type: IP (0x0800) <br>
Internet Protocol, Src Addr: 192.168.0.14 (192.168.0.14), Dst Addr: 192.168.0.1
(192.168.0.1) <br>
Version: 4 <br>
Header length: 20 bytes <br>
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00) <br>
0000 00.. = Differentiated Services Codepoint: Default (0x00) <br>
.... ..0. = ECN-Capable Transport (ECT): 0 <br>
.... ...0 = ECN-CE: 0 <br>
Total Length: 1500 <br>
Identification: 0x2274 <br>
Flags: 0x04 <br>
.1.. = Don't fragment: Set <br>
..0. = More fragments: Not set <br>
Fragment offset: 0 <br>
Time to live: 128 <br>
Protocol: TCP (0x06) <br>
Header checksum: 0x5148 (correct) <br>
Source: 192.168.0.14 (192.168.0.14) <br>
Destination: 192.168.0.1 (192.168.0.1) <br>
Transmission Control Protocol, Src Port: 1059 (1059), Dst Port: ftp-data
(20), Seq: 3897295803, Ack: 3505752771 <br>
Source port: 1059 (1059) <br>
Destination port: ftp-data (20) <br>
Sequence number: 3897295803 <br>
Next sequence number: 3897297251 <br>
Acknowledgement number: 3505752771 <br>
Header length: 32 bytes <br>
Flags: 0x0010 (ACK) <br>
0... .... = Congestion Window Reduced (CWR): Not set <br>
.0.. .... = ECN-Echo: Not set <br>
..0. .... = Urgent: Not set <br>
...1 .... = Acknowledgment: Set <br>
.... 0... = Push: Not set <br>
.... .0.. = Reset: Not set <br>
.... ..0. = Syn: Not set <br>
.... ...0 = Fin: Not set <br>
Window size: 17520 <br>
Checksum: 0x5ee6 (correct) <br>
Options: (12 bytes) <br>
NOP <br>
NOP <br>
Time stamp: tsval 117138, tsecr 68369212 <br>
FTP Data <br>
FTP Data: 6/14/2002\t6:06 PM\t\tAdministrator\tKAUAI\tExtracting Zip file
from stub file, C:\DOCUME~1\ADMINI~1\LOCALS~1\TEMP\~SDAT4UP.tmp\DATS\cdex4207.exe.\r\r\n6/14/2002\t6:06
PM\t\tAdministrator\tKAUAI\tPerforming self validation ...\r\ (it goes on
when viewing raw data...) <br>
<br>
( I Think the print statement of Ethereal did not correctly print the data
but if you look at ethereal <br>
capture of the raw data you see the hole payload) <br>
<br>
------------------------------------------------------------- <br>
<br>
Trace of Packet on AP side. <br>
<br>
Frame 43 (1522 on wire, 96 captured) <br>
Arrival Time: Apr 25, 2003 17:58:48.306638000 <br>
Time delta from previous packet: 0.017794000 seconds <br>
Time relative to first packet: 16.075410000 seconds <br>
Frame Number: 43 <br>
Packet Length: 1522 bytes <br>
Capture Length: 96 bytes <br>
Ethernet II <br>
Destination: 00:04:5a:72:e0:62 (The_72:e0:62) <br>
Source: 00:60:1d:04:78:54 (Lucent_04:78:54) <br>
Type: IP (0x0800) <br>
Internet Protocol, Src Addr: 192.168.0.14 (192.168.0.14), Dst Addr: 192.168.0.1
(192.168.0.1) <br>
Version: 4 <br>
Header length: 20 bytes <br>
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00) <br>
0000 00.. = Differentiated Services Codepoint: Default (0x00) <br>
.... ..0. = ECN-Capable Transport (ECT): 0 <br>
.... ...0 = ECN-CE: 0 <br>
Total Length: 1500 <br>
Identification: 0x2274 <br>
Flags: 0x04 <br>
.1.. = Don't fragment: Set <br>
..0. = More fragments: Not set <br>
Fragment offset: 0 <br>
Time to live: 128 <br>
Protocol: TCP (0x06) <br>
Header checksum: 0x5148 (correct) <br>
Source: 192.168.0.14 (192.168.0.14) <br>
Destination: 192.168.0.1 (192.168.0.1) <br>
Transmission Control Protocol, Src Port: 1059 (1059), Dst Port: ftp-data
(20), Seq: 3897295803, Ack: 3505752771 <br>
Source port: 1059 (1059) <br>
Destination port: ftp-data (20) <br>
Sequence number: 3897295803 <br>
Next sequence number: 3897297251 <br>
Acknowledgement number: 3505752771 <br>
Header length: 32 bytes <br>
Flags: 0x0010 (ACK) <br>
0... .... = Congestion Window Reduced (CWR): Not set <br>
.0.. .... = ECN-Echo: Not set <br>
..0. .... = Urgent: Not set <br>
...1 .... = Acknowledgment: Set <br>
.... 0... = Push: Not set <br>
.... .0.. = Reset: Not set <br>
.... ..0. = Syn: Not set <br>
.... ...0 = Fin: Not set <br>
Window size: 17520 <br>
Checksum: 0x5ee6 <br>
Options: (12 bytes) <br>
NOP <br>
NOP <br>
Time stamp: tsval 117138, tsecr 68369212 <br>
FTP Data <br>
FTP Data: 6/14/2002\t6:06 PM\t\tAdministrat <br>
<br>
(Notice the payload is cut off at 30 bytes - that is it looking at the print
format or raw format) <br>
<br>
<br>
<br>
<br>
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