71,478 reputation
790177
bio website
location
age 69
visits member for 2 years, 9 months
seen 41 mins ago

I SHALL DEVOUR YOUR HEART AND FEAST ON YOUR SOUL (so don't bug me).


4h
answered Password Cracking Mandarin Words English Character Set
5h
comment XTS vs AES-CBC with ESSIV for file-based filesystem encryption
GnuPG's better encryption comes from the fact that it processes the whole file in one go, with a fresh random IV. All the difficulty of FDE is that it tries to support efficient updates, where only the data chunks that are updated get reencrypted. In the file-on-Dropbox case, the encryption should really occur when uploading the filesystem image, not for each file write.
6h
comment XTS vs AES-CBC with ESSIV for file-based filesystem encryption
If you put the encrypted filesystem only once, then there is no problem. Just do it. Potential vulnerabilities begin to occur if you then retrieve the filesystem, modify it, then put it back on Dropbox: the successive versions become visible to attackers. What you can do is to take a filesystem image (not necessarily encrypted with anything), then encrypt it with GnuPG before upload, and decrypting it when downloading it. This will be stronger, both against passive and active attackers.
6h
revised XTS vs AES-CBC with ESSIV for file-based filesystem encryption
edited tags
6h
answered XTS vs AES-CBC with ESSIV for file-based filesystem encryption
6h
answered VPS Privacy: OpenVZ vs KVM vs Xen
7h
answered SHA and “Bits of Security”
7h
comment EAP-TLS fragmentation implementation
For the CertificateVerify, you must hash all previous messages, so ClientHello, ServerHello, Certificate (from server), ServerKeyExchange, CertificateRequest, ServerHelloDone, Certificate (the one from the client) and ClientKeyExchange.
9h
answered EAP-TLS fragmentation implementation
2d
answered Importance of password strength with secure element?
Jul
25
answered How is the Premaster secret used in TLS generated?
Jul
25
answered generating extensions request in a PKCS#10 request using C# and CertENrollLib
Jul
25
answered how can I tell if I'm under IMSI cell phone surveillance
Jul
25
revised How to generate a superkey to decrypt strings
edited tags
Jul
25
answered How to generate a superkey to decrypt strings
Jul
24
comment Can any ECC field element be safely serialized as “compressed” and then restored as uncompressed?
Usually, in crypto, we use finite groups and rings and fields, where there is no notion of negative at all, since there is no natural ordering of elements (you cannot have a "less than" relationship compatible with the group law on a finite group).
Jul
24
answered Can any ECC field element be safely serialized as “compressed” and then restored as uncompressed?
Jul
24
comment GPG encryption and signing
Yes, with --sign you sign but you do not encrypt. Distinct operations. The --armor is not about encryption (as in: hiding information from people who don't know some specific key) but about surviving alterations in transit (as in: some email server will convert LF end-of-line characters to CR+LF, or will replace what it supposes to be an "unprintable character" with a "?"). The "armoring" is about coping with the careless way email servers handle emails. On a similar note, Base64 is also internally used when you send a binary attachment, for pretty much the same reason.
Jul
24
answered GPG encryption and signing
Jul
24
answered “Web of trust” for self-signed SSL certificates?