Security

[12D687]

[cipriancraciun]

You mean something like this:

public: age1vdpuu34qlus5jce2pghn4t92g37tspcedl3gw5ruacpvdsuemfvqnsu05z
secret: AGE-SECRET-KEY-1RHX00SLTMZUFLNQNAFM9FN0Q54X4T4N6F0QFFU7XDE4286YQZPQQVLT3L6

The age1 in the public key is just a prefix that identifies the token as an AGEv1 public key. The actual public key is encoded in the other characters after the age1 according to the Bech32 encoding (see https://en.bitcoin.it/wiki/BIP_0173#Bech32). For the actual details see the AGEv1 specification at https://github.com/C2SP/C2SP/blob/main/age.md#the-x25519-recipient-type.

The encryption is based on Curve25519 and the keys are randomly generated, and although they are ~256 bits in length (a little less I think) they offer ~128 bits of security (according to the cryptographers).

Please note that by default the secret key is not password protected, thus a malicious intruder doesn't need to mine anything, he can just recover your secret key file.

[12D687]

[alerque]

The plain text label inside the secret key file is not part of the key itself and hence not part of the entropy calculation. It's not even a factor.

[FiloSottile]

Think about it like this: if you pick a number between 1 and 8, that has 3 bits of entropy, because there are 2^3 = 8 possible numbers that you chose, and I'll have to take on average 2^2 = 4 guesses to get it right.

If you add the letters age in front of the number, like age1, age2, age3, etc. the number did not get any easier to guess. There's still 8 possible values, and it still takes on average 4 guesses.

Here we have a 2^256 bit number (more or less, the math of elliptic curves is more complex than that, which is why that only has about 2^128 bits of security). It doesn't matter how we encode it, or what we add before it. It still takes a physically impossible time to guess.

[wqweto]

@12D687 This is not like the key is 1234 but it gets saved to age4 losing first 3 digits in the process.

It gets saved as age1234 without losing any digits i.e. "age" string is not replacing first 3 digits.