Blockstream Green BTC wallet - can't generate seed while offline?

[ovcijisir]

Few days ago I wanted to create cold wallet, but needed wallet app to create seed words.

My plan was following:

• 1. Factory reset old mobile phone
• 2. Connect it to wifi and download Blockstream Green wallet
• 3. Disconnect mobile phone from wifi
• 4. Generate seed words and few addresses
• 5. Write down seed words and scan addresses with other phone
• 6. Factory reset wallet again

It sounded great at first until I installed Blockstream wallet and disconnected mobile phone from wifi. To my surprise I got an error "Error connection failed". I was wondering why would wallet need Internet connection in order to generate new wallet? Why can't it pick 11 words and calculate checksum without Internet connection?

To me it sounds like possible security weakness. I'm not saying it is deliberate and don't want to accuse Blockstream of anything, but it does rise a red flag.


At the end I used Bluewallet app which also gave me error when I tried to generate seed offline, but I managed it in the end.

Anyone had similar problem? What could be good alternative to Blockstream app to generate BIP 39/ BIP 44 compatible wallet ?

[Charles-Tim]

I use the Android version just now offline with wifi and mobile network off and I was able to create a wallet with it. I went to where seed phrase is I saw the seed phrase. It worked offline. I mean Blockstream Green.

Bluewallet is also working offline when I tested it last. I checked it now and it worked also. The only problem about the wallet is that it is heavy to load at first but it will work.

[OmegaStarScream]

I just installed the app and tried doing that (android) and it's working fine. I created the wallet -> went to "Security" tab --> clicked "back up" and it's showing me the seed phrase just fine (6 words, then you click continue to see the other 6).

But as an alternative, you can check Electrum (for android) or Unstoppable wallet.

[hosemary]

But as an alternative, you can check Electrum (for android) or Unstoppable wallet.

It's may worth mentioning that the seed phrase generated by electrum isn't BIP39. Electrum uses its own algorithm for generating seed phrase.
If you want to have a BIP39 seed phrase, you can generate an electrum seed phrase and then change the last word until the seed phrase passes BIP39 checksum.

[satscraper]

~
What could be good alternative to Blockstream app to generate BIP 39/ BIP 44 compatible wallet ?

If I were faced with the similar task, I would probably use flipping coin to generate entropy and subsequent SEED phrase for my wallet.

Pros:

• Truly airgapped and offline method
• which doesn't require trust in any RNG
• and besides is free of backdoors

If you are interested find step-by-step guide here.

[ovcijisir]

I use the Android version just now offline with wifi and mobile network off and I was able to create a wallet with it. I went to where seed phrase is I saw the seed phrase. It worked offline. I mean Blockstream Green.

Bluewallet is also working offline when I tested it last. I checked it now and it worked also. The only problem about the wallet is that it is heavy to load at first but it will work.

I tried it two times and both times it game me same error. Ill try to recreate this situation one more time and send screenshot. I don't know if it is possible that cell phone model is cause of that error?

But as an alternative, you can check Electrum (for android) or Unstoppable wallet.

It's may worth mentioning that the seed phrase generated by electrum isn't BIP39. Electrum uses its own algorithm for generating seed phrase.
If you want to have a BIP39 seed phrase, you can generate an electrum seed phrase and then change the last word until the seed phrase passes BIP39 checksum.

I recreated wallet with seed that I got from Blue wallet in Electrum that ran on Tails OS. There was message in Electrum that it uses different word list, because BIP 39 does not satisfy their security standards. If I remember correctly BIP 39 don't include version of software or BIP standard (I know something about versioning was the reason). I insisted on BIP 39 because more wallets support it and I guess this is most widespread wallet standard now.

Edit. Added this reply that was posted before I clicked send button.

~
What could be good alternative to Blockstream app to generate BIP 39/ BIP 44 compatible wallet ?

If I were faced with the similar task, I would probably use flipping coin to generate entropy and subsequent SEED phrase for my wallet.

Pros:

• Truly airgapped and offline method
• which doesn't require trust in any RNG
• and besides is free of backdoors

If you are interested find step-by-step guide here.

I first considered to generate seed words by hand, but calculating checksum (12th word) seemed too complicated. I don't have any software to generate hash and I know very little about cryptography so I simplified seed generating processes by using wallet software.

[hosemary]

There was message in Electrum that it uses different word list,

No, the default word list of electrum is same as BIP39.

There was message in Electrum that it uses different word list, because BIP 39 does not satisfy their security standards.

Don't worry about the security.
Whether your seed phrase is BIP39 or it has been generated by electrum, if your seed phrase is generated on an airgapped device, you are safe.

If you want to import your BIP39 seed phrase into electrum, just check 'BIP39" option.

I first considered to generate seed words by hand, but calculating checksum (12th word) seemed too complicated.

The checksum isn't the 12th word. The checksum is the last 4 bits.

[satscraper]

I first considered to generate seed words by hand, but calculating checksum (12th word) seemed too complicated. I don't have any software to generate hash and I know very little about cryptography so I simplified seed generating processes by using wallet software.

You could use offline Ian Coleman's BIP39 generator for such task. How to:

• put your first 11 words into BIP39 Mnemonic field
• take any subsequent 16 words from BIP39 list
• enter on the place of 12^th word "each of the 16 words until the converter accepts your seed phrase as successful"

[hosemary]

• take any subsequent 16 words from BIP39 list
• enter on the place of 12^th word "each of the 16 words until the converter accepts your seed phrase as successful"

This is not true.
If you have the first 11 words of 12 word BIP39 seed phrase, 1/16 of the words will give a valid seed phrase if they are used as the 12th word, but this doesn't mean any subsequent 16 words will include 1 word that will give you a valid seed phrase.
For example, it's possible that none of the first 16 words can be used as the 12th word.

[satscraper]

• take any subsequent 16 words from BIP39 list
• enter on the place of 12^th word "each of the 16 words until the converter accepts your seed phrase as successful"

For example, it's possible that none of the first 16 words can be used as the 12th word.

I won’t believe your claim until you provide the proof. I’ve tested dozens of valid BIP39 seed phrases, and this method has consistently worked. 

So, please provide the valid 12 word seed and an example set of 16 consecutive words from the BIP39 word list  such that none of those 16 words can satisfy the checksum requirement as the 12th word for the first 11 words of that seed.

[ovcijisir]

I use the Android version just now offline with wifi and mobile network off and I was able to create a wallet with it. I went to where seed phrase is I saw the seed phrase. It worked offline. I mean Blockstream Green.
~

Just wanted to do quick follow-up regarding this issue.

I did same steps on another cell phone that had Blockstream Green pre-installed.

1. I turned off mobile data and wifi
2. Clicked on upper right button -> Setup a new wallet -> Get started -> Setup mobile wallet -> Entered PIN
3. After that I get "Creating wallet..." message for a minute
4. Finally I get "Error Connection failed"

Also version is 5.0.7.

So wallet definitely can't be produced while offline, at least with my phones and this version of software.

Unfortunately I couldn't make any screenshots because app doesn't allow making them.

[dkbit98]

Anyone had similar problem? What could be good alternative to Blockstream app to generate BIP 39/ BIP 44 compatible wallet ?

All mobile wallets you mentioned are created as hot wallets, so they are trying to connect to the internet every time you open the app.
I suspect this is the main reason why you are having this error issues, since you disabled internet connection.
Airgap.it created app with special purpose to be used as cold wallet, but you can also generate seed phrases offline separately using iancoleman website:
https://iancoleman.io/bip39/

[Charles-Tim]

Anyone had similar problem? What could be good alternative to Blockstream app to generate BIP 39/ BIP 44 compatible wallet ?

All mobile wallets you mentioned are created as hot wallets, so they are trying to connect to the internet every time you open the app.
I suspect this is the main reason why you are having this error issues, since you disabled internet connection.
Airgap.it created app with special purpose to be used as cold wallet, but you can also generate seed phrases offline separately using iancoleman website:
https://iancoleman.io/bip39/

I am surprised that you did not test the wallet and you just believed what the OP posted after OmegaStarScream and I tested it and posted that it worked fine offline.

@ovcijisir
Make sure you downloaded the right Blockstream Green app
https://play.google.com/store/apps/details?id=com.greenaddress.greenbits_android_wallet
https://f-droid.org/en/packages/com.greenaddress.greenbits_android_wallet

Official website: https://blockstream.com/app/

[hosemary]

So, please provide the valid 12 word seed and an example set of 16 consecutive words from the BIP39 word list  such that none of those 16 words can satisfy the checksum requirement as the 12th word for the first 11 words of that seed.

OK. Here is an example.


The first 11 words:

Code:

half mango galaxy baby just mix able divide fog pattern cause

Words number 20 - 35 (16 consecutive words from BIP39 wordlist):

Code:

20. act
21. action
22. actor
23. actress
24. actual
25. adapt
26. add
27. addict
28. address
29. adjust
30. admit
31. adult
32. advance
33. advice
34. aerobic
35. affair

None of the words 20-35 can be used as the 12th word to have a valid seed phrase.

[ovcijisir]

Anyone had similar problem? What could be good alternative to Blockstream app to generate BIP 39/ BIP 44 compatible wallet ?

All mobile wallets you mentioned are created as hot wallets, so they are trying to connect to the internet every time you open the app.
I suspect this is the main reason why you are having this error issues, since you disabled internet connection.
Airgap.it created app with special purpose to be used as cold wallet, but you can also generate seed phrases offline separately using iancoleman website:
https://iancoleman.io/bip39/

Thank you Dkbit98 this will definitely be great for generating secure seed in future!

Unfortunately now I will stick to this seed I generated few days ago on BlueWallet app, because I already made cryptosteel backup and generated 15 addresses on Tails OS.

Interesting thing - BlueWallet generated seed offline (after error message, but at the end it still managed it),  BUT it wouldn't allow me to generate addresses offline - thats why I had to start Tails OS and regenerate wallet and addresses in Electrum
I believe  generating seed on BlueWallet was safe because I made factory reset without going online, so the phone didn't touch the internet after generating seed at any point.


This may be a little bit off topic, but is there tool that allows ti input seed (while choosing custom derivation path and coin type) in order to get the keys? I'm asking that be because I used one deprecated wallet(not Bitcoin) that used derivation path that other wallets not support and now I'm stuck with funds locked. Software like reverse of Ian Coleman would be ellegant solution for my problem.

@ovcijisir
Make sure you downloaded the right Blockstream Green app
https://play.google.com/store/apps/details?id=com.greenaddress.greenbits_android_wallet
https://f-droid.org/en/packages/com.greenaddress.greenbits_android_wallet

Official website: https://blockstream.com/app/

It is definitely correct app, downloaded from Play store. There is definitely something fishy going on with this wallet, I wouldn't trust it definitely at least with more significant sums.

I tried to generate wallet many times without success and I am not sure how could it be generated without online acces? Are you guys 100% sure that your phone was completely offline all the time after downloading Blockstream Green? Also do we have same version of software ( mine is 5.0.7.)?

[satscraper]

So, please provide the valid 12 word seed and an example set of 16 consecutive words from the BIP39 word list  such that none of those 16 words can satisfy the checksum requirement as the 12th word for the first 11 words of that seed.

OK. Here is an example.


The first 11 words:

Code:

half mango galaxy baby just mix able divide fog pattern cause

Words number 20 - 35 (16 consecutive words from BIP39 wordlist):

Code:

20. act
21. action
22. actor
23. actress
24. actual
25. adapt
26. add
27. addict
28. address
29. adjust
30. admit
31. adult
32. advance
33. advice
34. aerobic
35. affair

None of the words 20-35 can be used as the 12th word to have a valid seed phrase.

But 38 - "again" matches it.

Any rule has the exceptions. If you are unlucky just move a bit further. Two - three words ahead don't make any difference.

BTW 7 - "absorb" from first 16^th also matches.

Always start from the first 16^th and go further step-by-step. It doesn't take too much time to find correct word by proposed method. Cheese.

[hosemary]

Unfortunately now I will stick to this seed I generated few days ago on BlueWallet app, because I already made cryptosteel backup and generated 15 addresses on Tails OS.

ovcijisir, it was better to save your master public key.
Now, if you need more addresses, you will have to use your seed phrase again. Instead, you could save your master public key and generate any number of addresses you want from that without using your seed phrase.

Any rule has the exceptions. If you are unlucky just move a bit further. Two - three words ahead don't make any difference.

You said "provide the valid 12 word seed and an example set of 16 consecutive words from the BIP39 word list  such that none of those 16 words can satisfy the checksum requirement as the 12th word for the first 11 words of that seed." and I did.

Words number 7 and 38 are out of the 16 consecutive words I mentioned.
I prefer not to continue this off-topic discussion, but if you want an example in which none of the first 16 words of the BIP39 wordlist can't give you a valid seed phrase if they are used as the 12th word, I can provide that too.

[Charles-Tim]

Interesting thing - BlueWallet generated seed offline (after error message, but at the end it still managed it),  BUT it wouldn't allow me to generate addresses offline - thats why I had to start Tails OS and regenerate wallet and addresses in Electrum

I was also able to generate new wallet on Bluewallet offline and also I was able to get the addresses and master public key which can be imported for watch-only wallet.

I tried to generate wallet many times without success and I am not sure how could it be generated without online acces? Are you guys 100% sure that your phone was completely offline all the time after downloading Blockstream Green? Also do we have same version of software ( mine is 5.0.7.)?

Yes, my phone was completely offline. I like to test several wallets. Wallet like Blockchain.com and Metamask for altcoins and few other ones have been the ones that did not pass the test before and that is the reason they are called web wallet. Mobile and desktop wallets should be able to generate keys and addresses offline.

[dkbit98]

I am surprised that you did not test the wallet

My wallet testing or not-testing doesn't change anything.
I clearly said that some wallets are created to work as hot wallets and that is true.

Thank you Dkbit98 this will definitely be great for generating secure seed in future!

There is another interesting open source wallet app that is created to work air-gapped, and you can consider checking it out.
This is Cupcake app created to work with Bitcoin and Monero, and it can also be connected with some hardware wallets or Cake wallet:
https://blog.cakewallet.com/air-gapped-privacy-made-easy-meet-the-new-cupcake-experience/

[Charles-Tim]

I clearly said that some wallets are created to work as hot wallets and that is true.

Only web wallets can not be used offline. Mobile and desktop wallet can still work offline if you want. That is the reason they are called mobile and desktop wallet. If you see any wallet that is a mobile or desktop app and not working offline to generate keys and addresses, it is a web wallet, the close source unrecommended blockchain.com is am example. Blockstream Green, Bluewallet, Electrum and some others are not web wallet and they can be used offline despite being a software (mobile or desktop) wallet.