Meanwhile I've got the D-link sat on the side of my desk and am using it as a Wifi access point, while having a go at extracting the password generation code.

It is built around a Broadcom BCM63281KFBG, which according to a pdf I found on the Broadcom website, is a cost effective, low power chip, with support for power management. The Wifi chip is a BCM4313KML1G - single-band, IEEE 802.11n, with dual antenna support, although the router itself is only b and g capable.
As you can see there's minimal shielding on the wireless section, and judging by the PCB, the bcm63281 has an integrated switch. The inclusion of a power button at the rear, proved to be very useful while I was trying to access the shell.
It has four external Ethernet ports, and supports wireless 802.11b & g. The sky firmware includes support for WPA & WPA2, although you can't select WPA2 only. The firmware seems pretty good at automatically selecting an unused wifi channel, however it sometimes picks a channel used by a neighbour, possibly because they have their SSID hidden, so I found it necessary to manually select one.
The wifi signal is a little weak compared to my other routers, probably because of the internal antenna - the bit of steel with a wire attached at the bottom of the picture. I also wonder if they've limited the power output, to avoid causing interference issues due to the lack of shielding. There are unused solder pads on the PCB for a second antenna.
Mounting the router vertically improved the wifi reception by about 15%, and also makes the router run much cooler. It gets quite toasty while sitting on it's rubber feet, as the vents are at either end of the case. The wifi signal still doesn't match that of my other router's though, or even my neighbour's, it is however, more than adequate to reach opposite ends of my house.
Anyway, before trying to flash it, I wanted to try to access the shell, which, as it doesn't seem to have a telnet or ssh server running, requires a little hacking...
Getting root access didn't provide me with that much of a challenge, although the procedure I used did get a little complicated.
Needless to say it runs busybox under linux:-
BusyBox v1.00 (2010.06.23-05:56+0000) Built-in shell (msh) Enter 'help' for a list of built-in commands. # ls bin dev lib mnt proc sys usr webs data etc linuxrc opt sbin tmp var # # ls /bin adsl dnsproxy iptables ps true adslctl dnsspoof kill pwd udhcpd brctl dsldiagd ln pwr umount busybox dumpmem ls pwrctl upgrader cat eapd mcpd rawSocketTest upnp chmod ebtables mkdir rm urlfilterd consoled echo mknod sendarp vlanctl cp epi_ttcp mount setmem wl date ethctl msh sh wlctl ddnsd ethswctl nas sleep wlevt deluser false nas4not smd wlmngr df fc nvram sntp xdslctl dhcpc fcctl nvramUpdate ssk xtm dhcpd flash_eraseall ping sysinfo xtmctl diapd hotplug ping6 telnetd dmesg httpd pppd tftpd # # ls /sbin ethctl ifconfig insmod logread rmmod syslogd hotplug init klogd reboot route vconfig # # help Built-in commands: ------------------- . : break cd continue eval exec exit export help login newgrp read readonly set shift times trap umask wait [ busybox cat chmod cp date deluser df dmesg echo expr false flash_eraseall ftpget ifconfig init insmod kill killall klogd linuxrc ln logger logread ls mkdir mknod mount msh nc ping ping6 ps pwd reboot rm rmmod route sendarp sh sleep sysinfo syslogd test tftp tftpd top true tty umount vconfig wget # # cat cpuinfo # system type : 96328avng processor : 0 cpu model : Broadcom4350 V7.5 BogoMIPS : 319.48 wait instruction : yes microsecond timers : yes tlb_entries : 32 extra interrupt vector : no hardware watchpoint : no ASEs implemented : shadow register sets : 1 core : 0 VCED exceptions : not available VCEI exceptions : not available # #
Mem: 24400K used, 36880K free, 0K shrd, 2676K buff, 9752K cached Load average: 0.13, 0.08, 0.01 (State: S=sleeping R=running, W=waiting) PID USER STATUS RSS PPID %CPU %MEM COMMAND 158 admin SW 0 2 1.7 0.0 bcmsw 1098 admin R 404 1096 0.5 0.6 exe 1002 admin S 140 1 0.1 0.2 telnetd 844 admin S 1576 187 0.0 2.5 httpd 188 admin S 1448 187 0.0 2.3 ssk 531 admin S 1392 187 0.0 2.2 wlmngr 187 admin S 724 114 0.0 1.1 smd 233 admin S 640 187 0.0 1.0 mcpd 608 admin S 532 187 0.0 0.8 upgrader 1005 admin S 500 1 0.0 0.8 pppd 114 admin S 464 1 0.0 0.7 sh 1096 admin S 448 1002 0.0 0.7 sh 195 admin S 416 187 0.0 0.6 syslogd 1 admin S 392 0 0.0 0.6 init 196 admin S 344 187 0.0 0.5 klogd 197 admin S 340 187 0.0 0.5 sntp 609 admin S 288 187 0.0 0.4 dsldiagd 250 admin S 216 1 0.0 0.3 dnsspoof 803 admin S 212 1 0.0 0.3 nas 799 admin S 124 1 0.0 0.2 eapd ^C# # # #
Running the PPP daemon manually, reveals that "ps" masks the chap password with a couple of asterisks.
1005 admin 500 S pppd -c pppoa0 -a 0.0.38 -u mel@btbroadband.com -p ** 1096 admin 448 S /bin/sh 1103 admin 388 R ps
/bin/pppd -c pppoa0 -a 0.0.38 -u USERNAME -p PASSWORD -f0 -z1500&
Obviously you'd need access to the shell first (I've written a program to provide telnet access and also to extract the password) and I suspect "pppd" will need to be run before connecting the router to the telephone line.
Finding a compatible firmware may prove to be very tricky though, I was hoping it would be the same hardware as the broadcom based dsl-2640b, however this router's design seems to be a new one.
Update
D-Link have released the GPL source code
30 comments:
any chance you could publish the hack you used to gain access?
Yes. Just got one of these with my Sky broadband connection and we need a hack to extract the user id and password from it. It's not using the same userid and password generator as the previous Sky modems so they have changed their security approach again.
Just tried to telnet in. Telnet seems to be running but terminates immediately without prompts. Suspect it needs an embedded login or passkey sequence.
I've written an app to extract the authentication details, and hope to make it available very soon.
Could you tell us which exploits you used?
So does that mean it can be upgraded to single band N at some point
via sofware?
Presumably apart from new firmware, it would require a second antenna, and there might also be a few components required for 802.11N missing. I also can't be absolutely sure if this version of the BCM4313 does support N as I wasn't able to find any details about the full product code.
Mel,
I've ordered an antenna and pigtail set and plan to retrofit it to the router.
Is there any way to find out if the WIFI power output has been restricted? Or if it's possible to increase the output? (like WRT).
Many thanks.
Is there any news on what firmware could be used on this, I always hated sky's firmware on the older Netgear and I quickly flashed to a Netgear official one so I am hoping to do the same with this router if possible (Currently running SKY 1.11)
No problems but I really wish it was a d-link firmware and interface.
Yes I second that. Non-Sky firmware would be a bonus.
By the way, retro fitted a 9inch high gain antenna and this vastly improved the wifi signal. I initially tried a 6inch antenna and this made an improvement but the 9inch one was even better. The antennas are only £1.50 off ebay anyway :-) and I had 2 reverse polarity pigtails for £3. Cheap and cheerful upgrade! You need a pretty good soldering iron and good eye sight as the solder pads are a bit small. I'll try and get a photo on here later.
Here it is, sorry about the quality.
http://img17.imageshack.us/img17/8599/skyrouter.jpg
Could you post a picture of the bottom of the board? I'm thinking of getting one of these and try to get OpenWRT to run on this, but I need serial access for that, and I didn't see any serial pins on the top.
Ah, almost forgot: does it come with *any* hints that it runs GPL'd software?
I think the serial pins are at the top of Mels picture. To the left of the bank of LAN sockets, and just to the right of the reset switch. You can just about make them out.
Got them. If anyone is interested, the serial settings are 115200 8N1, while the pins are (from "top"): [RX] [X] [VCC?][GND] [TX].
Hi Alex,
Thx for reading. Your photo here http://img17.imageshack.us/img17/8599/skyrouter.jpg
shows the external appearance of the modifications you did successfully.
Is there anyway you could publish the photo details of the soldering pads on the board, like location?
Hi Alex,
Thx for reading. Your photo here http://img17.imageshack.us/img17/8599/skyrouter.jpg
shows the external appearance of the modifications you did successfully.
Is there anyway you could publish the photo details of the soldering pads on the board, like location?
Hi!
Did any of you got the chance to grab the gpl source dump for the 1.11 version from D-Link's site? I think they took them down, can't find them anywhere. I've even e-mailed them about this and they replied with a generic "we-ll look into it" mail.
I managed to find 2.04 sources but I couldn't get any of the built images to boot, although everything appears to compile fine, board ids and everything check out (I'll provide the link on request)... The power and checkmark leds light up and that's all, it just hangs there. At least recovery works.
Thanks!
please provide the link for the source code skyV2.04
please provide the link for the source code skyV2.04
The GPL'ed source code for the Sky-branded DLink DSL-2640s is here..
http://blog.gmane.org/gmane.law.gpl.violations.legal/month=20111201
http://www1.sky.com/opensourcesoftware/router/downloads.html
Where is Mel's source code now?
Apparently, the source archives published by sky are stripped of the binary drivers (aka useless if you want to use the dsl bit, possibly other stuff). I have not confirmed this myself yet, but I am looking into it.
On the other hand, the sources that I grabbed from ftp://ftp.dlink.co.uk/dlinktemp/DSL-2640S%20V2.04%20GPL%20Source%20Code/ build fine, and I have been able to flash a working image compiled from source.
I've been trying to modify the source to enable arbitrary vci/vpi and username/password combinations, but I haven't had too much free time to work on it, so progress is really slow, if any.
I also built working firmware from the source provided by d-link, and even modified them a bit. However to build a generic firmware, I had to resort to hacking around firmware extracted from another router.
I'm using it now, and I almost got it good enough to release, but there's still one major bug.
Hi Mel, Doru & all,
I'm interested to know the progress of building/trying/using generic firmware for this DLink type, as I'm trying to use it for other ISP. May I know at least how you access it via telnet? I only know some basic of Unix.
Thanks
Hi Mel, Any chance you are any closer to releasing the firmware you have built?
Hi Mel,
Im currently looking at the D-Link dsl-2640s as a possible option for dd-wrt or alternative firmware flash. Im struggling to find very much information at all about the router other than what I found on your site (great site btw).
Are you still progressing this as a project?
Could you share your discoveries so far on how to gain telnet / ssh access to the router and any other information you are happy to part with? I would be very greatful as well as mentioning you in any resulting blog etc.
All the best either way! :)
Hi Mel,
Im currently looking at the D-Link dsl-2640s as a possible option for dd-wrt or alternative firmware flash. Im struggling to find very much information at all about the router other than what I found on your site (great site btw).
Are you still progressing this as a project?
Could you share your discoveries so far on how to gain telnet / ssh access to the router and any other information you are happy to part with? I would be very greatful as well as mentioning you in any resulting blog etc.
All the best either way! :)
Pretty good post. I just stumbled upon your blog and wanted to say that I have really enjoyed reading your blog post.
d-link support
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