MavEtJu's Distorted View of the World - 2006-02
Why the Samsung SGH-D600 sucks
Funny GCC error messages Stop abusing my computer in DDOSes, thanks RAD IPMux 8 and 11 trouble Back to index Why the Samsung SGH-D600 sucksPosted on 2006-02-17 14:34:25, modified on 2006-02-17 15:32:01 The D600 is a nice looking phone, but it's user interface has some bad design issues.
No comments | Share on Facebook | Share on Twitter Funny GCC error messagesPosted on 2006-02-16 22:27:51, modified on 2006-02-16 22:28:58
This is while compiling zaptel on a FC4 linux machine with gcc 4.0.0.
Stop abusing my computer in DDOSes, thanksPosted on 2006-02-15 13:22:52, modified on 2006-02-15 13:55:21
Dear Script kiddies, Blackmailers and other thugs on the internet,
13:05 I get a phone call via my VoIP phone. Halfway the call, the call, it just drops dead and I see the phone rebooting. Funny, not something I see often since I moved from wireless ADSL to just-use-an-ethernet-ADSL. 13:06My VPN connection is... getting... very... sluggish. Yes, sluggish is the word. Trafshow to the rescue! 13:06Wonder why there is so much DNS traffic going on: From Address To Address Prot Bytes CPS 63.214.168.62..15796 192.168.1.1..53 udp 48193 11632 192.168.1.1..53 63.214.168.62..15796 udp 488276 65655 A general WTF comes up in my mind. Anyway, now that I know it's DNS traffic, let's see what it is. 13:07# tcpdump -s 1500 -ni sk0 port 53 13:07:17.035118 IP 63.214.168.62.20435 > 192.168.1.1.53: 15043+ [1au] ANY ANY? x.p.ctrc.cc. (40) 13:07:17.035258 IP 192.168.1.1.53 > 63.214.168.62.20435: 15043- 1/1/2 TXT[|domain] 13:07:17.176355 IP 63.214.168.62.15879 > 192.168.1.1.53: 13909+ [1au] ANY ANY? x.p.ctrc.cc. (40) 13:07:17.176515 IP 192.168.1.1.53 > 63.214.168.62.20435: 13909- 1/1/2 TXT[|domain] 13:07:17.225230 IP 208.222.0.82.9761 > 192.168.1.1.53: 24263+ [1au] ANY ANY? x.p.ctrc.cc. (40) 13:07:17.225398 IP 192.168.1.1.53 > 208.222.0.82.9761: 24263- 1/1/2 TXT[|domain] Somebody is asking my nameserver for x.p.ctrc.cc. Why me? And why do I give answers (and why is 1500 bytes not enough to hold the answer? First things first:13:09# ipfw -a l ipfw add 50 deny udp from 63.214.168.62 to me dst-port 53 ipfw add 51 deny udp from 208.222.0.82 to me dst-port 53 Why does my nameserver actually answer this request? I mean, I'm not authoritative and I have disabled recursion and I have... oh wait... This new machine still has a virgin named running. 13:15acl nobody { none; }; acl everybody { any; }; acl we { 192.168.0.0/16; 127.0.0.0/8; }; options { allow-recursion { we; }; }; I forgot, the payload. Why wasn't 1500 bytes enough to hold the answer? $ dig x.p.ctrc.cc any ;; Truncated, retrying in TCP mode. ; <<>> DiG 9.3.1 <<>> x.p.ctrc.cc any ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55082 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1 ;; QUESTION SECTION: ;x.p.ctrc.cc. IN ANY ;; ANSWER SECTION: x.p.ctrc.cc. 81842 IN TXT "............................... ................................................................................ ................................................................................ ................................................................" "............. ................................................................................ ................................................................................ ................................................................................ .." "........................................................................... ................................................................................ [...] ............................................................................" ". ................................................................................ ........" ;; AUTHORITY SECTION: p.ctrc.cc. 81842 IN NS 321blowjob.com. ;; ADDITIONAL SECTION: 321blowjob.com. 27224 IN A 66.98.217.195 ;; Query time: 12 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Wed Feb 15 13:30:05 2006 ;; MSG SIZE rcvd: 4015 That's 4015 bytes of data to be sent out for every request. No wonder my VoIP phone dropped out. Moral of the storyKeep your configurations secure. Do not allow SMTP relaying, do not allow DNS recursion. There are people out there who don't play nice. 13:50Weblog finished :-) No comments | Share on Facebook | Share on Twitter RAD IPMux 8 and 11 troublePosted on 2006-02-08 17:58:54, modified on 2006-02-08 21:05:06 The IPMux are TDMoIP (Time Division Multiplexer over IP) devices, to transport E1/T1s over an IP network. The IPMux 8 requires a female DB9 serial cable for it's console, which comes default on 19200 bps. You can see it booting. If your cable doesn't set the DCD, you will see still see it booting, but the IPMux won't accept the data from it. So if you wonder why the IPMuxes don't respond to your keystrokes, make sure you use the cable coming with it! The IPMux 11 on the other hand requires a male DB9 serial cable, and it set to 115200 bps (note the two differences). If you try to define the timeslots on a bundle on it, and the current bundle is active, it will not accept any changes but will only say "ERROR", while not giving a hint of what the error is. After disabling the bundle, you can edit the timeslots. No comments | Share on Facebook | Share on Twitter |