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seen Oct 12 '12 at 19:43

Feb
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awarded  Popular Question
Sep
30
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Sep
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Sep
30
comment Tool for public key cryptography where password is the private key?
For me publishing encrypted private key is bad, because it gives people easy target to try brute force attacks (otherwise they need to first steal my encrypted backup files), there is still some chance I will loose that published private key files or they are tampered with. Also, some attackers could monitor my access to such published private key and easily trace me, etc. Since it gives no extra security over just password-as-private-key, and has many drawbacks, I want to avoid the private key file altogether.
Sep
30
comment Tool for public key cryptography where password is the private key?
Yes, I do code in C, did you have another solution using C?
Sep
30
comment Tool for public key cryptography where password is the private key?
Cryptico sounds like it has the functionality I need. However, is the way they generate the private key standard? Does any such standard exist? I would love to be able to reproduce it with at least one other tool.
Sep
30
comment Tool for public key cryptography where password is the private key?
I was thinking about feeding my password to OpenSSL as the PRNG seed, as you suggest, but I am afraid the results are not cross-platform, cross-version and cross-tool reproducible. They can change the way PRNG works between versions or it could work differently on various machines. I would like a solution that has it as its well documented and supported functionality, so I can decrypt my backup few years from now on a different computer.
Sep
30
comment Tool for public key cryptography where password is the private key?
Nothing that would enable decrypting the backup can be stored in the backup script. Symmetric encryption will not do. I also want to use this for other scenario where people send me encrypted messages. So in both cases I need public key cryptography.
Sep
29
comment Tool for public key cryptography where password is the private key?
@DavidWachtfogel I agree, they are as secure. Actually people often have a weak password (or none) protecting the private key file, as they don't plan for when attacker gets it, so maybe a password being directly the private key would make them choose something strong. However, we are drifting off-topic, as the question wasn't about how secure or advisable the proposal is, but simply how to implement it.
Sep
29
comment Tool for public key cryptography where password is the private key?
@ThomasPornin I am aware of problems with weak passwords, and I would choose a strong one.
Sep
29
revised Tool for public key cryptography where password is the private key?
More clarification.
Sep
29
comment Tool for public key cryptography where password is the private key?
I'm in one of those scenarios where I don't want to ever share the data, and if I'm hit by the bus, I don't want anybody to unlock my backups, including people who would get physical access to my computers after I'm gone (having private key in a file would only help them).
Sep
29
comment Tool for public key cryptography where password is the private key?
If private key is in the file, more copies in more locations increases probability that an attacker will get it.
Sep
29
comment Tool for public key cryptography where password is the private key?
I don't agree with your brute-force-attack-drawback. The very same thing can be done with usual private-key. How is guessing my decryption password different than guessing my private key?
Sep
29
awarded  Editor
Sep
29
revised Tool for public key cryptography where password is the private key?
Clarified assumptions.
Sep
29
awarded  Student
Sep
29
asked Tool for public key cryptography where password is the private key?