Linux

I’m always reading about dangerous rogue access points but never actually have seen one in action. So what better than create a test setup.. Hardware for this test setup will be my old linux notebook (a macbook pro) as fake access point a small deal extreme network card (Ralink 5070 chipset). I’ve actually bought three differnet wireless cards for under $20 and am trying out the different chipsets. This card is rather small (like an usb stick), so it isn’t to conspicous The basic idea is to use hostap to create a virtual access point. Would I be a hypothetical attacker I’d call it ‘starbucks’, ‘freewave’ or name it like some coffee shop around the corner. I’m using the notebook’s included wireless card to provide an internet uplink. To achieve this I will have to compile a custom version of squid (including ssl support). I’m using Ubuntu 13.10 for this, other linux distributions would work the same. ...

I’m contributing to a secure cloud project (well, it’s not that secure yet, but getting there..). It’s backend storage options include S3 so I want to test the S3-functionality against a locally installed S3 server. I first tried to utilize OpenStack Object Storage (Swift) or Riak, but both solutions were rather heavy-weight and cumbersome to setup. Bear in mind, that I just wanted some fake S3 storage server which would be deployed within a local network (without any internet connection). So security, authentication, performance was mostly moot. ...

I’ve changed my approach and am now using a simple docker setup to achieve the same result Somehow I have to use VPN services throughout the day: when pen-testing from abroads I really need to login to my company’s network first. Otherwise my provider is kinda grumpy when I’m doing fast non-cloaked scans against large companies. also when pen-testing I like to use some cloaking VPNs to test the client’s detection capabilities if I would ever use bit-torrent I’d really like to make sure that the torrent program can only communicate through a private proxy (as pia). The easy solution would be to connect the openvpn tunnels on startup and just route all the traffic through the tunnels. Alas this is way to slow for daily use – and somehow error prone: if a tunnel dies and some pen-test is currently under progress traffic might escape into ‘unsecured’ public networks. The same would be true for torrents. ...

This is part three of a series about encrypted file storage/archive systems. My plan is to try out duplicity, git using transparent encryption, s3-based storage systems, git-annex and encfs+sshfs as alternatives to Dropbox/Wuala/Spideroak. The conclusion will be a blog post containing a comparison a.k.a. “executive summary” of my findings. Stay tuned. git was originally written by Linus Torvalds as SCM tool for the Linux Kernel. It’s decentralized approach fits well into online OSS projects, it slowly got the decentralized OSS of choice for many. Various dedicated hosted storage services as github or bitbucket arose. In this post I’ll look into using git as replacement for Dropbox for data sharing. As Dropbox has a devastating security history (link needed) I’ll look into ways of transparently encrypting remote git repositories. ...

This is part two of a series about encrypted file storage/archive systems. My plan is to try out duplicity, git using transparent encryption, s3-based storage systems, git-annex and encfs+sshfs as alternatives to Dropbox/Wuala/Spideroak. The conclusion will be a blog post containing a comparison a.k.a. “executive summary” of my findings. Stay tuned. Duplicity is a command-line tool similar to rsync: you give it two locations and it synchronizes the first location to the second. Duplicity adds additional features over rsync, especially interesting for me are incremental encrypted backups to remote locations. This form of storage would prevent any hoster of gaining any information about my stored data or its metadata (like filenames, etc.). ...

Last week’s World Conference on International Telecommunications (WCIT) brought internet surveillance into public news: one outcome of the conference was standardization of DPI technology. This infrastructure standard will make it easier for governments to implement large-scale surveillance and/or filtering. Funny thing is that governments are already having those capabilities, they only want to standardize it. The public outrage came too late. So let’s protect you from governments at home or abroad, the RIAA, MPAA, random eavesdroppers and anyone else that want to listen in on your secrets while you’re surfing the Internet. The initial steps are easy and cheap (or free), so there’s no reason let your security down. They might not be perfect but making the government’s job more expensive seems to be a good road to take. ...

Imagine your Laptop (or Desktop Computer) being stolen. How long will it take and how much will it cost you to get back on track? Hardware will be easy: the cost for a new premium desktop is around $1000, for a new Laptop around $2000. Your data “should” be always be back-uped somewhere anyways. But this neglects a hidden cost: some thief has all your data, including all your online identities, photos, source for software projects and private notes/pictures that you do not want to be published. How much would you value your online reputation, would you change all your online account passwords and connected applications on theft? How much time and effort would this cost you – and could you do it fast enough before the attacker might utilize that data against you? ...

Another small tip: to locally forward port 80 to port 3000 use the following Linux iptables command: $ sudo iptables -t nat -A PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 3000 You can use this command to allow customers to connect to your locally run Ruby on Rails setup (as long as you have some port forwarding set up on your local router). I am using this to develop facebook open graph apps as the application URL (that is configured within facebook’s app controll page) cannot include a custom port (like 3000). ...

Just a small tip for today: when moving an RoR-application between servers the database user often changes. While it is easy to dump and restore database dums using pg_dump and pg_restore this might lead to invalid table ownerships on the new host. I’m using the following bash snippet for fixing this problem ...

OctoPress is embraced for its simplicity: write blog posts, save them, generate HTML pages and move those upon a web server. As no code is executed server-side every page can be cached and security risks are low. So far I’m hosting my blog on a rented hetzner root-server in Germany. While there’s no server-side security problem I’m still using a full blown server which imposes maintenance overhead on me. No peace of mind. An alternative would be moving to the cloud (Amazon’s S3 storage in my case), but is it worth it? ...