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by ubutler1 hours ago |
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upvoteby ahartmetz35 minutes ago|
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Rule 3: Use as many bits of randomness as the key size.

Rule 3b: Failing rule 3, disclose motivations and full list of employers and / or customers

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upvoteby j16sdiz1 hours ago|
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That's why we use the system RNG !
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upvoteby cowlevel54 minutes ago|
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Be careful to use the cryptographic one, not rand(3)

And if you're a sysadmin, be extremely careful when generating keys in VMs or embedded devices. They tend to overestimate their entropy sources - it's possible that every clone of a VM generates the same keys. In some cases (cough ECDSA) generating the same key and nonce to sign two different messages is catastrophic - it immediately leaks the private key.

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upvoteby saidnooneever20 minutes ago|
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good point about VMs. if you run some VPS your provider could just link in a shitty rng into the thing and not give access to the correct hardware rng. U'd really need to dig into that to find out :/.

-object rng-random,id=objrng0,filename=/dev/null

or maybe just a file that contains 4 :O

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upvoteby 23 minutes ago|
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deleted
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upvoteby flanz_101 hours ago|
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btw, the idea that the system rng isnt good enough, or "runs out" or whatever, is no longer true on pretty much every modern, widely used os.

btw... im sure there's some legacy rng in windows or some shit that isnt good. read the docs but if it's the blessed system rng, you're probably fine!

although... i suppose if this is news to you (the person reading this), then you probably shouldn't be implementing whatever you are that really requires prng. ask a friend for help. im not trying to be a jerk, i just want to make sure you dont hurt yourself!

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