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  1. Just saw this on Slashdot. It looks like Asus watches Hak5. http://www.itworld.com/hardware/138740/asus-motherboard-box-doubles-a-pc-case
  2. When are you guys bringing back the shot glasses? I just barely missed them when they were originally offered and I've been waiting ever since. Is there an issue with sponsors/rev3 and selling shot glasses?
  3. That PHP Code That You Wrote For ./asleap.. i used it in a facebook application.. and gave credit to you for the code.. BTW that's an awesome piece of code.


  4. I'm glad my passwords are all different and have a key space of 2^74.82 except a few like my bank and myspace. They have password length limits of 8 and 10 respectively. If I used myspace I might care, last logged in 11/8/2008 :). Ohh and a few web sites I use frequently but they're all at least 2^46, hmm maybe I should fix those.
  5. I tested it with a bunch of block sizes and it looks like 64k wins at 5.8MB/s. I'm also outputting it to /dev/null which is faster than writing it to disk. I ran an analysis program for "detecting non-randomness in binary sequences constructed using random number generators and pseudo-random number generators utilized in cryptographic applications" and it looks like the program I wrote passed more tests than /dev/urandom. Also I don't think changing the block size to anything else will magically increase speed since I am just dumping the data into /dev/null. Ohh also "bs=512b" is not 512 bytes it is actual 512*512 bytes since b stands for block (512 bytes). Something wired that I found is if you pipe something into dd and you set the block size to like 1 MiB it messes up. For some reason these don't work: cat /dev/zero | dd of=/dev/null bs=1024k count=1k 7+1017 records in 7+1017 records out 12115968 bytes (12 MB) copied, 0.01437 seconds, 843 MB/s dd if=/dev/zero | dd of=/dev/null bs=1024k count=1k 1+1023 records in 1+1023 records out 1648128 bytes (1.6 MB) copied, 0.006307 seconds, 261 MB/s But these work: cat /dev/zero | dd of=/dev/null bs=1k count=1024k 1048576+0 records in 1048576+0 records out 1073741824 bytes (1.1 GB) copied, 2.18704 seconds, 491 MB/s dd if=/dev/zero bs=1024k | dd of=/dev/null bs=1024k count=1k 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 0.677182 seconds, 1.6 GB/s The analysis program can be found here http://csrc.nist.gov/groups/ST/toolkit/rng/index.html
  6. dd if=/dev/urandom of=/dev/hda I'm doing that for each hard drive. dd if=/dev/urandom of=/dev/null 97724+0 records in 97723+0 records out 50034176 bytes (50 MB) copied, 8.85633 seconds, 5.6 MB/s ./rndsha256 | dd of=/dev/null 2553448+0 records in 2553448+0 records out 1307365376 bytes (1.3 GB) copied, 9.67982 seconds, 135 MB/s
  7. I had this problem with wanting to write random data to a hard drive before setting it up with encryption. The problem is that I have 6 TB of disk and /dev/urandom was going around 5.5 MB/s which this will take almost two weeks to finish. I came up with a solution but I don't know if it's that good, since I have no formal training in cryptography. I wrote my own random number generator which took /dev/urandom as a seed for SHA-256 then incremented the seed and generated a new SHA-256 and so on. Kinda like this only I wrote SHA-256 in SSE2 (64 bit x86) which gave me over 100 MB/s per core in a Pentium D. SHA256_CTX ctx; int seed[16]; FILE *pFile = fopen("/dev/urandom", "rb"); while (1) { fread(seed, 4, 16, pFile); for (int a = 0; a < 1048576; a++) { sha256_init(&ctx); sha256_update(&ctx, seed, 64); fwrite(&ctx, 4, 8, stdout); seed[0]++; } } What is a faster way than /dev/urandom that is still cryptographically secure? Also I'd like to know if my solution is cryptographically secure?
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