Monday, August 29. 2005
Back from Evoke
Sometimes you think the world is really small - so I met my room-neighbor Julian in Cologne. He was hanging around in a location called "Kletterfabrik" near the Evoke-location, where some cool people did some art installations. I made pictures, but they are quite dark (it was in the night).
I'll upload some more pictures in the next days.
The 64k-Intro Bloom from Styx made the second place and he was quite happy about that.
After coming home I was really tired (you don't get too much sleep on a demoparty) and angry about the "Deutsche Telekom", because our DSL isn't working at the moment.
I'll upload some more pictures in the next days.
The 64k-Intro Bloom from Styx made the second place and he was quite happy about that.
After coming home I was really tired (you don't get too much sleep on a demoparty) and angry about the "Deutsche Telekom", because our DSL isn't working at the moment.
Sunday, August 28. 2005
Evoke 2005 Report
I'm here at the Evoke 2005 demoparty with Tom, StyX and TS.
I tried to create a 4k-Intro on friday evening, but stopped due to the late time and the deadline, which was at 10 (although it was moved for hours later). StyX has created a 64k-Intro, which has probably good chances to gain a good place, maybe even the first.
The network is always sucking here (and we're asking us why it is so difficult to provide a working network), so if this entry reaches you, I managed to get internet for some minutes ;-)
Pictures I made are here
I tried to create a 4k-Intro on friday evening, but stopped due to the late time and the deadline, which was at 10 (although it was moved for hours later). StyX has created a 64k-Intro, which has probably good chances to gain a good place, maybe even the first.
The network is always sucking here (and we're asking us why it is so difficult to provide a working network), so if this entry reaches you, I managed to get internet for some minutes ;-)
Pictures I made are here
Friday, August 26. 2005
Evoke 2005
In about two hours I'll leave to have a trip to the demoparty Evoke. If netcologne manages it to provide internet this year you may see live-reports from me. I have no releases prepared, as I'm mostly a passive scener in recent times.
If you don't know what a demoparty is, it's basically an event where people are creating art with computers, in form of self-running programs, while their only use is that they provide nice graphics and sound.
If you are a loyal reader of my blog, you might know that one of the very first entries in this blog was about my Evoke-Trip last year.
If you don't know what a demoparty is, it's basically an event where people are creating art with computers, in form of self-running programs, while their only use is that they provide nice graphics and sound.
If you are a loyal reader of my blog, you might know that one of the very first entries in this blog was about my Evoke-Trip last year.
Monday, August 22. 2005
Some more background information about SHA1
As the article some days ago about SHA1 got a lot of interest, I thought I'll write some more background info about this, especially for people thinking that collisions aren't a big problem.
Cryptographic hash functions are functions where you can put a string of any length and get a fixed-size result. E. g. with SHA1, you get 160 bit, with MD5 128 bit. The hash-function has to fulfill some requirements:
- It should be hard to get two strings with the same hash (collision-resistant).
- It should be hard to get a string to a given hash (one-way-function).
To be more precise: In an optimal case, hard means that it shouldn't be possible with all hardware on earth in the timeframe that your cryptography needs to be secure. Some examples where cryptographic hashes are used are shadown-passwords, digital signatures or verification of file downloads.
Cryptographic hash functions are functions where you can put a string of any length and get a fixed-size result. E. g. with SHA1, you get 160 bit, with MD5 128 bit. The hash-function has to fulfill some requirements:
- It should be hard to get two strings with the same hash (collision-resistant).
- It should be hard to get a string to a given hash (one-way-function).
To be more precise: In an optimal case, hard means that it shouldn't be possible with all hardware on earth in the timeframe that your cryptography needs to be secure. Some examples where cryptographic hashes are used are shadown-passwords, digital signatures or verification of file downloads.
Continue reading "Some more background information about SHA1"
Posted by Hanno Böck
in Code, Cryptography, English, Gentoo, Linux
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00:30
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Saturday, August 20. 2005
Nostalgic feelings - Secret Maryo Chronicles

Secret Maryo Chronicles
The gameplay is a bit different from the original games, it doesn't have a speedup-button. It's features are comparable to Super Mario Bros, while it's graphics are more like Super Mario World.
It's free software and it's available for Windows and Linux.
Posted by Hanno Böck
in Computer culture, English, Gentoo, Linux, Retro Games
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00:20
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Thursday, August 18. 2005
Say goodbye to SHA-1
Xiaoyun Wang, chinese cryptographer and well known for her analysis of the SHA1 function, was not allowed to travel to the US to attend the Crypto conference starting today (via Bruce Schneier).
Too bad, because she discovered some new results on the attacks on SHA1, which reduce it to a complexity of 2^63 to generate a collission. Adi Shamir, well known cryptographer and one of the RSA-inventors, presented these results.
These news are important, because 2^63 is a complexity that can be broken with todays hardware if you invest enough money and time. This would be an interesting project for distributed computing, although I don't know if the attack can be implemented on common hardware (maybe someone with cryptographic experiences wants to comment if this is possible).
Too bad that most software devs have not noticed the recent results on hash-functions. Most of them still use MD5 (which has been broken about a year ago), SHA-1 is widely used. The GNU Coreutils don't have any tools for modern hash-functions, same goes with most programming languages (PHP, Python), while they implement some sort of md5sum or sha1sum, no sha256sum or whirlpoolsum at all.
Too bad, because she discovered some new results on the attacks on SHA1, which reduce it to a complexity of 2^63 to generate a collission. Adi Shamir, well known cryptographer and one of the RSA-inventors, presented these results.
These news are important, because 2^63 is a complexity that can be broken with todays hardware if you invest enough money and time. This would be an interesting project for distributed computing, although I don't know if the attack can be implemented on common hardware (maybe someone with cryptographic experiences wants to comment if this is possible).
Too bad that most software devs have not noticed the recent results on hash-functions. Most of them still use MD5 (which has been broken about a year ago), SHA-1 is widely used. The GNU Coreutils don't have any tools for modern hash-functions, same goes with most programming languages (PHP, Python), while they implement some sort of md5sum or sha1sum, no sha256sum or whirlpoolsum at all.
Posted by Hanno Böck
in Code, Cryptography, English, Gentoo, Linux, Politics
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00:31
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Monday, August 15. 2005
Anonymizer and ad-blocking Proxy (tor and privoxy)
I recently installed privoxy and tor and Lars asked me to write some words about it. So here it goes:
Privoxy is an ad-blocking proxy, which means it filters out banners, pop-ups and other annoying stuff. It's highly configurable, but I use it in the basic configuration, which should be enough for most needs. The advantage is that privoxy, unlike for example the firefox ad-block extensions, can be used within any browser. It's the successor of junkbuster.
tor is a project by the Electronic Frontier Foundation, an internet anonymizing system. It's internals are complex, but the basic funktion is that you connect encrypted to a tor-node, it forwards your request through several other tor-nodes and then it get's answered. It doesn't provide full anonymity, you have to trust the tor-node you connect to. But it's definitely better than nothing.
Both integrate well, if you are a Gentoo user, just emerge tor pricoxy, add forward-socks4a / localhost:9050 . to your /etc/privoxy/config, copy the torrc.sample to torrc (in /etc/tor), add both to your runlevels (rc-update add tor default, rc-update add privoxy default) and you are done.
Now set your Browser to use Proxy localhost and Port 8118.
For other Linux-Distributions, it's probably similar. I have no idea if and how tor and privoxy work on other OSes (especially the evil one with the W), so don't ask me, you'll have to find out yourself.
This will save you some privacy and you'll get rid from a lot of internet ads.
Note: tor had some security-issues recently, so take care that you use the latest version available (0.1.0.14).
Privoxy is an ad-blocking proxy, which means it filters out banners, pop-ups and other annoying stuff. It's highly configurable, but I use it in the basic configuration, which should be enough for most needs. The advantage is that privoxy, unlike for example the firefox ad-block extensions, can be used within any browser. It's the successor of junkbuster.
tor is a project by the Electronic Frontier Foundation, an internet anonymizing system. It's internals are complex, but the basic funktion is that you connect encrypted to a tor-node, it forwards your request through several other tor-nodes and then it get's answered. It doesn't provide full anonymity, you have to trust the tor-node you connect to. But it's definitely better than nothing.
Both integrate well, if you are a Gentoo user, just emerge tor pricoxy, add forward-socks4a / localhost:9050 . to your /etc/privoxy/config, copy the torrc.sample to torrc (in /etc/tor), add both to your runlevels (rc-update add tor default, rc-update add privoxy default) and you are done.
Now set your Browser to use Proxy localhost and Port 8118.
For other Linux-Distributions, it's probably similar. I have no idea if and how tor and privoxy work on other OSes (especially the evil one with the W), so don't ask me, you'll have to find out yourself.
This will save you some privacy and you'll get rid from a lot of internet ads.
Note: tor had some security-issues recently, so take care that you use the latest version available (0.1.0.14).
Posted by Hanno Böck
in Cryptography, English, Gentoo, Linux
at
21:42
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Vulnerability in various PHP apps (XMLRPC-bug)
Stefan Esser, who writes a blog about php security that is really worth reading, discovered several vulnerabilities in the PEAR XMLRPC lib. Various PHP applications use this, especially all major blog-systems, including wordpress and serendipity. So please update your blog-software.
Sunday, August 14. 2005
Project Orange - Open Movie Project
As I often wrote about free films in the past, this might be of interest:
Project Orange, an effort to create an animated Movie, based on the free software Blender and all content released under a Creative Commons license. Looks promising, surely worth to keep an eye on it.
Project Orange, an effort to create an animated Movie, based on the free software Blender and all content released under a Creative Commons license. Looks promising, surely worth to keep an eye on it.
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