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bio website moserware.com
location Fishers, IN
age 32
visits member for 2 years, 11 months
seen Jun 20 at 12:18
10 PRINT "HELLO WORLD!"
20 GOTO 10

Aug
19
comment Any good file format alternative to PGP for encrypting data at rest?
Thanks for your thoughtful write-up! A few thoughts: 1. I was assuming I'd use OpenSSL such that you'd have to enter the key via stdin instead of the command line. 2. Since the keys would effectively be entered in manually, I wanted to keep the key size as small as possible. The only way I see to reconcile it is to have a key derivation function that expanded the key into the actual cipher key and then the HMAC key. 3. I hadn't considered scrypt. Would you recommend it over PGP for encrypting single files in terms balancing simplicity but still having security? (ignoring Salsa20 issues?)
Aug
19
comment Any good file format alternative to PGP for encrypting data at rest?
I was just wanting to use whatever is common already so that I can write a simple script to decrypt it if things like OpenSSL are already available. Is it best to just use an HMAC on the existing OpenSSL file along with the key? I'd then just need a simple way with unix tools to strip that hash off the end and then verify it. Right now I might be leaning towards something like [OpenSSL Salted file encrypted with key X, HMAC256(key bytes || IV || encrypted file contents)] but am open to better ideas
Aug
19
comment Any good file format alternative to PGP for encrypting data at rest?
I only care about symmetric ciphers, and realistically only AES 128 and AES256. I was thinking the default file extension would be ".aes128" and ".aes256". My key will be random bytes the size of what the cipher expects. However, it'd be nice to also have a passphrase to key bytes function specified. Regardless, the file format needs the IV as I'll probably use CBC mode.
Aug
3
comment How does asymmetric encryption work?
I added a small synopsis, but without pictures and captures like I have on my blog
Aug
2
comment Design properties of the Rijndael finite field
I believe the designers picked the specific polynomial because it was the first irreducible one from the book they cited that met their criteria. Thus, they picked the first one to remove the doubt that it was special.