Alice bought 1 Bitcoin and encrypted her wallet.dat in Bitcoin Core.
Samantha, Alice’s friend, notices the Bitcoin price skyrocketing and, while Alice is in the bathroom, steals Alice’s wallet.dat
as well as important.txt
and goes home.
There she discovers that it’s passphrase-protected, so she cannot transfer the coin away to her own wallet.
Alice opens important.txt
and discovers this:
Never delete the following!!!
Bitcoin passphrase: "ck3C83jcdldkj3isDkj2m3Db3ducMJm3wb3kdkxckDksk2kw54956848dkDkdkewj54t" + first_pet_nickname + house_number_for_second_temporary_house + guy_in_first_grade_i_had_a_crush_on + favorite_brand_of_cakes (all lowercase letters)
In other words, Alice has written down part of the passphrase with the rest being things that Samantha possibly could guess or brute-force.
My question is: assuming that she can’t just guess the unknown parts, and has to brute-force it, does the sheer length of the known part pose any kind of extra hurdle?
That is, has the passphrase just turned into simply first_pet_nickname + house_number_for_second_temporary_house + guy_in_first_grade_i_had_a_crush_on + favorite_brand_of_cakes
? Since the first string is known, does that mean it “doesn’t exist” as far as brute-force time/resources needed? Or will this add significantly to the slowness of the brute-forcing because it has to do different (more complex) calculations with the long string as compared to without it?