Author

Topic: Who can explain how BIP-39 phrases work? (Read 256 times)

HCP
legendary
Activity: 2086
Merit: 4318
November 30, 2018, 05:57:47 PM
#7
be careful that you have to add that 1 only if you are choosing the words manually by looking at that list, as in (1207=1208th word).
but you never do that ...
OP wants to manually choose his own words... so that is EXACTLY what he is trying to do Tongue


Quote
... since you would be using a programming language and these words are placed in an array and AFAIK in all language arrays start from index 0.
While most of the popular languages do index from 0, off the top of my head LUA and XPath/XQuery both index from 1. Turns out there are also a few others... (refer: "Default Base Index" column)
legendary
Activity: 2352
Merit: 6089
bitcoindata.science
November 30, 2018, 05:29:22 AM
#6
What is checksum used in BIP-39 and what is it for? I don’t trust programs that generate 12 words,

Everywhere I read about cryptography , all those smart guys say that humans are a terrible source of randomness. We are always trying to make a pattern or something like that.

If you want security, and don't want someone to brute Force or to somehow discover your keys, you definitely should try some reliable program to generate your seed/keys. That's the most common advice i see out there. As I am not a genius, I just follow it Smiley

You can help me? How can I convert my 12 words that I chose myself, from a list of 2048 words, into a wallet?


https://iancoleman.io/bip39/

In this website you can put any 12 words ant it will generate thousands of addresses and privatekey for them
Use it only of you have an airgapped (offline) computer, otherwise there is a small risk that someone may be watching (if infected computer).

For educational purposes, try your words there  ... If checksum fails, it will Tell you.
legendary
Activity: 3472
Merit: 10611
November 30, 2018, 12:37:06 AM
#5
(note: you have to add 1... as the bit range values are 0-2047, but the wordlist as shown on github is indexed from 1-2048)

be careful that you have to add that 1 only if you are choosing the words manually by looking at that list, as in (1207=1208th word).
but you never do that since you would be using a programming language and these words are placed in an array and AFAIK in all language arrays start from index 0. so in your array the word at index 1207 is the same as 1208th word in that list.
HCP
legendary
Activity: 2086
Merit: 4318
November 29, 2018, 05:41:53 PM
#4
You're doing BIP39 wrong... the process is explained quite clearly within the BIP39 documentation here: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki#generating-the-mnemonic

You don't START with 12(/15/18/21/24) words... you start with the necessary amount of ENTROPY... ie. a very large random number.
You can help me? How can I convert my 12 words that I chose myself, from a list of 2048 words, into a wallet?
If you want to choose your own (a really bad idea btw)... you will be able to choose 11... and then the 12th word you'll need to find through trial and error to find the one or two that generate the correct checksum.

Also, note that Electrum does NOT use BIP39 unless you select the "Options" button and check the "BIP39 Seed" option. It uses it's own custom (NON-BIP39) method for calculating seed checksums etc.



The last 7 bit of a 12 word seed are the checksum.
It's not... it's only 4 bits for a 12 word seed, as per the table above from the BIP39 docs
legendary
Activity: 1624
Merit: 2481
November 29, 2018, 05:41:48 PM
#3
The last 7 bit of a 12 word seed are the checksum.

A checksum is to prevent typos. It is a way to easily know whether your seed is a valid one or not.

The probably fastest way would be to choose 11 words from the list, and then try out the 12th word. You need to try out 16 different words for the last spot ON AVERAGE to receive a valid checksum.


But.. please note that a human brain choosing those words from the list can NEVER be as random as a random number generator. You are giving away quite some bits of strength.
newbie
Activity: 3
Merit: 0
November 29, 2018, 05:37:41 PM
#2
You can use https://github.com/iancoleman/bip39/releases/latest on offline computer and write down generated seed to paper
newbie
Activity: 6
Merit: 0
November 29, 2018, 05:18:37 PM
#1
What is checksum used in BIP-39 and what is it for? I don’t trust programs that generate 12 words, since I don’t know what algorithm they are working on, and for this I wanted to take 12 words from the total 2048 bip-39 word list, but if I do, and after that I want to get using my words to access my wallets, for example using this script https://github.com/iancoleman/bip39 I get an error Invalid mnemonic.

I'm in a dead end, I'm afraid if I use the 12 words that I chose from the general list, because of the checksum error, I will lose my bitcoins in the future, please clarify. I'm at a dead end, I'm afraid if I use the 12 words that I chose myself from the general list of words, I will lose my bitcoins in the future because the programs will not want to accept my words, because of the checksum error. You can help me? How can I convert my 12 words that I chose myself, from a list of 2048 words, into a wallet?

At the moment I can choose any 12 words at my discretion, and Electrum will accept them, but with an unkown wordlist error.

Can you explain to me how the checksum check works, and what is it for in BIP-39?
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