Bitcoin Forum

I am looking for a thread that I found a few years ago. It showed step by step how to create offline cold storage using USB sticks with Ubuntu and Bitaddress.org.

I tried googling and searching this thread but I can't find it.

This may be the one you are talking about (skipping step 0 for brain wallets of course):

https://bitcointalk.org/index.php?topic=342691.0

Another one... http://docs.electrum.org/en/latest/coldstorage.html

Do you know if there are any newer guides? Seems everything there is outdated, even the Ubuntu version.

What is electrum exactly? Its like Ubuntu version of a bitcoin wallet?

Which method is safer for cold storage ?

It is a different wallet.

https://electrum.org

This could be useful too:
https://www.bitcoinarmory.com/cold-storage/

Both Electrum and Bitcoin Armory need two computers for cold storage one always kept offline. Pretty much supplanted by hardware wallets I took Armory off my computers when Trezor came out.

I just need something to put once in my cold storage and not take it out for a few months or years.

Paper wallets are an ideal way to store your bitcoin for the foreseeable future but if you can afford it then you would gain an additional bit of protection by using a hardware wallet such as a trezzor. It makes it much easier to spend as well and no need to make sure your pc is completely clean to transfer bitcoins etc. A paper wallet is free obviously but hard to beat the trezzor.

Here's a quick step-by-step guide:

1. Run your Bitcoin client on a clean and secure computer that is disconnected from the Internet. (We're going to assume that no one is spying on your screen and that no delayed screencap malware or keylogger is installed on your computer.)
2. Generate a new Bitcoin address.
3. Save your Bitcoin address on a text file, or write it down on a piece of paper. (This is only necessary if you intend to check the contents of your cold storage address from block explorers sometime in the future. You really should be doing that occasionally anyway.)
4. Dump your address's private key and write it down on a piece of paper. Hide it and do not allow anyone access to it unless necessary.
 -- OR --
4. Encrypt your wallet.dat file and save it on a clean USB drive. Hide the USB drive somewhere safe and do not allow anyone access to it unless necessary.
 ( -- OR BOTH --)
5. Secure-wipe your wallet.dat file from your computer. Secure-wipe your computer's hard drive if you feel it necessary to do so.

And that's it. No fancy hardware or software required.

Hi,

just my two cents: I wanted to have cold sorage without any dependencies to other libraries. Just rely on OpenSSL.
So I created a set of shell scripts, which would run on a standard Unix-type platform (I have OpenBSD, OSX and SuSE Linux).
I could manage to do the whole cycle with some scripts, see here in this forum:

https://bitcointalk.org/index.php?topic=1505958.0

The script relevant for this would be "trx_create_sign.sh", use '-h' param for explanation, and the README.md.
It is currently limited to a single previous trx, prev output, and a single P2PKH out.

Generally: when using this approach, you HAVE TO BE very, very careful on the amounts (input - output = trx fee !).


rgds,
Volker

I've used this guide and I found it really helpful. Ofir includes screenshots to make I extra simple.

https://99bitcoins.com/create-99-9-secure-bitcoin-paper-wallet/
 (https://99bitcoins.com/create-99-9-secure-bitcoin-paper-wallet/)
This is a guide on how to make secure paper wallets made on an Ubuntu Live USB/CD. If you have questions he'll respond to you too, it's great!

Just wanted to add a piece of fancy hardware in case your USB drive is stolen:  8)
http://www.apricorn.com/aegis-secure-key-3-0.html

Quick questions

1)

Anyway to verify if the download at
https://github.com/pointbiz/bitaddress.org/archive/master.zip

Is legit? Any SHA codes to verify?


2) Anyway to verify if the public address has the correct private key offline? I rather make sure its able to open the wallet before I send a bunch of BTC there that I won't be able to retrieve.

It isn't a binary so you can just read the source code yourself to verify its legitimacy.

You could import it into a wallet offline and check that you get the right private key. Then you can delete that wallet.

Do you know if laser printers like this keep any data stored on them if I wanted to print in Linux?

http://h10003.www1.hp.com/digmedialib/prodimg/lowres/c01953267.jpg

So is there any cold storage guides for the overly paranoid ? I remember there was one somewhere posted but can't find it, it might of been on another forum.

Depends, most of the newer ones do. Check if there is some form of memory stated on it. Mine has 8MB (http://support.brother.com/g/b/spec.aspx?c=us_ot&lang=en&prod=hl2130_all) of memory.

---

---

It is actually not that easy to spend paper wallets safely. If you want, you can purchase a raspberry pi for less than $50, install raspbian, install and check Electrum. Use the Electrum on your computer connected to your internet to craft and broadcast transactions.

Basically,
1. Generate the unsigned transaction on your Electrum wallet on your online computer.
2. Transfer the unsigned transaction from your Electrum wallet to your offline wallet and sign it.
3. Next, transfer the signed transaction back and broadcast it.

I do it like this:

- Download the latest Tails OS: https://tails.boum.org/index.en.html
- Download latest Bitcoin Core: https://bitcoin.org/en/choose-your-wallet
- Download the latest GPG4USB: https://www.gpg4usb.org/download.html

Verify the downloads, burn Tails on DVD, put Bitcoin Core and GPG4USB on a clean USB

then

1. Start a computer with the TailsOS (Higher sec: randomly buy a new and packed computer and USB stick for that) and disable your network and WLAN card.
2. Start GPG4USB and create a new keypair with a strong password. Export your GPG private key and save the file on your USB
3. Start Bitcoin core and create a new wallet. Copy the public wallet address to a textfile and save it on your USB (or write it down, if you don't want your public address being digitalized). Encrypt the wallet within Bitcoin Core with another password.
4. Encrypt the ~/.bitcoin/wallet.dat file with your new GPG keypair and copy the GPG encrypted file to the USB stick. Check back, if you can (edit: decrypt) encrypt both, Bitcoin wallet and GPG file. Always remember: If you later lose your wallet file and/or can't remember your passwords, you lose everything in that wallet.
5. Shutdown


You can now send funds to the public address of your offline wallet.

(1) Download generator from https://bitcoinpaperwallet.com/ (https://bitcoinpaperwallet.com/).
(2) Verify against PGP key on website.
(3) Transfer generator to USB.
(4) Roll dice, total of 36 rolls, write down.
(5) Run a Linux cold boot from a USB (not the same one used for the generator), plug in other USB, do not connect to internet.
(6) Create a wallet, BIP38 encrypt it with the written dice rolls, print to file, transfer to USB.
(7) Use USB to get wallet printed.
(8) Cut and fold (don't tape yet), leaving space for the encryption key.
(9) Write key on extra space.
(10) Use decrypt/verify option (from the cold boot) to decrypt the wallet and check it against the address.
(11) Tape up the wallet, it can now be used to store bitcoin.
Here is a wallet that failed step 10, no bitcoin was sent to it (image flipped horizontally):
https://i.imgur.com/0TYStmr.jpg

Would any of you guys here trust a trezor with cold storage? It would be quite an effortless option but obviously most of the guides above leave less space for doubt.

I too always wondered about the true safety of a trezor and how much the people who use them trust to them in btc. I think they have sold quite a few so a lot of people seem to trust them. I don't have enough btc to really worry too much about this stuff but I've always considered a trezor for under 20 btc. Anyone really take one of those things apart and really look at the code front to back to insure the safety of the device?

not only would but are trusting-I have a Trezor and is very happy with it
of course it is an effortles(albeit costing 100$) option
all the methods above describe a secure self made cold storage,they are almost free to set up,unlike hardware wallets



their code is open,read  http://doc.satoshilabs.com/trezor-faq/ for more info

Yeah, from what I have read, Trezor seems to be a pretty secure way of storing your coins although a pretty big initial cost to get the device. You could also look into the Ledger hardware wallet. They are a bit on the cheaper site but might not be as feature rich as the Trezor.