What is a BIP (Bitcoin Improvement Proposal)? Why do you ...

Groestlcoin 6th Anniversary Release


Dear Groestlers, it goes without saying that 2020 has been a difficult time for millions of people worldwide. The groestlcoin team would like to take this opportunity to wish everyone our best to everyone coping with the direct and indirect effects of COVID-19. Let it bring out the best in us all and show that collectively, we can conquer anything.
The centralised banks and our national governments are facing unprecedented times with interest rates worldwide dropping to record lows in places. Rest assured that this can only strengthen the fundamentals of all decentralised cryptocurrencies and the vision that was seeded with Satoshi's Bitcoin whitepaper over 10 years ago. Despite everything that has been thrown at us this year, the show must go on and the team will still progress and advance to continue the momentum that we have developed over the past 6 years.
In addition to this, we'd like to remind you all that this is Groestlcoin's 6th Birthday release! In terms of price there have been some crazy highs and lows over the years (with highs of around $2.60 and lows of $0.000077!), but in terms of value– Groestlcoin just keeps getting more valuable! In these uncertain times, one thing remains clear – Groestlcoin will keep going and keep innovating regardless. On with what has been worked on and completed over the past few months.

UPDATED - Groestlcoin Core 2.18.2

This is a major release of Groestlcoin Core with many protocol level improvements and code optimizations, featuring the technical equivalent of Bitcoin v0.18.2 but with Groestlcoin-specific patches. On a general level, most of what is new is a new 'Groestlcoin-wallet' tool which is now distributed alongside Groestlcoin Core's other executables.
NOTE: The 'Account' API has been removed from this version which was typically used in some tip bots. Please ensure you check the release notes from 2.17.2 for details on replacing this functionality.

How to Upgrade?

If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), then run the installer.
If you are running an older version, shut it down. Wait until it has completely shut down (which might take a few minutes for older versions), run the dmg and drag Groestlcoin Core to Applications.

Other Linux



Download the Windows Installer (64 bit) here
Download the Windows Installer (32 bit) here
Download the Windows binaries (64 bit) here
Download the Windows binaries (32 bit) here
Download the OSX Installer here
Download the OSX binaries here
Download the Linux binaries (64 bit) here
Download the Linux binaries (32 bit) here
Download the ARM Linux binaries (64 bit) here
Download the ARM Linux binaries (32 bit) here


ALL NEW - Groestlcoin Moonshine iOS/Android Wallet

Built with React Native, Moonshine utilizes Electrum-GRS's JSON-RPC methods to interact with the Groestlcoin network.
GRS Moonshine's intended use is as a hot wallet. Meaning, your keys are only as safe as the device you install this wallet on. As with any hot wallet, please ensure that you keep only a small, responsible amount of Groestlcoin on it at any given time.





ALL NEW! – HODL GRS Android Wallet

HODL GRS connects directly to the Groestlcoin network using SPV mode and doesn't rely on servers that can be hacked or disabled.
HODL GRS utilizes AES hardware encryption, app sandboxing, and the latest security features to protect users from malware, browser security holes, and even physical theft. Private keys are stored only in the secure enclave of the user's phone, inaccessible to anyone other than the user.
Simplicity and ease-of-use is the core design principle of HODL GRS. A simple recovery phrase (which we call a Backup Recovery Key) is all that is needed to restore the user's wallet if they ever lose or replace their device. HODL GRS is deterministic, which means the user's balance and transaction history can be recovered just from the backup recovery key.



Main Release (Main Net)
Testnet Release


ALL NEW! – GroestlcoinSeed Savior

Groestlcoin Seed Savior is a tool for recovering BIP39 seed phrases.
This tool is meant to help users with recovering a slightly incorrect Groestlcoin mnemonic phrase (AKA backup or seed). You can enter an existing BIP39 mnemonic and get derived addresses in various formats.
To find out if one of the suggested addresses is the right one, you can click on the suggested address to check the address' transaction history on a block explorer.


Live Version (Not Recommended)





ALL NEW! – Vanity Search Vanity Address Generator

NOTE: NVidia GPU or any CPU only. AMD graphics cards will not work with this address generator.
VanitySearch is a command-line Segwit-capable vanity Groestlcoin address generator. Add unique flair when you tell people to send Groestlcoin. Alternatively, VanitySearch can be used to generate random addresses offline.
If you're tired of the random, cryptic addresses generated by regular groestlcoin clients, then VanitySearch is the right choice for you to create a more personalized address.
VanitySearch is a groestlcoin address prefix finder. If you want to generate safe private keys, use the -s option to enter your passphrase which will be used for generating a base key as for BIP38 standard (VanitySearch.exe -s "My PassPhrase" FXPref). You can also use VanitySearch.exe -ps "My PassPhrase" which will add a crypto secure seed to your passphrase.
VanitySearch may not compute a good grid size for your GPU, so try different values using -g option in order to get the best performances. If you want to use GPUs and CPUs together, you may have best performances by keeping one CPU core for handling GPU(s)/CPU exchanges (use -t option to set the number of CPU threads).






ALL NEW! – Groestlcoin EasyVanity 2020

Groestlcoin EasyVanity 2020 is a windows app built from the ground-up and makes it easier than ever before to create your very own bespoke bech32 address(es) when whilst not connected to the internet.
If you're tired of the random, cryptic bech32 addresses generated by regular Groestlcoin clients, then Groestlcoin EasyVanity2020 is the right choice for you to create a more personalised bech32 address. This 2020 version uses the new VanitySearch to generate not only legacy addresses (F prefix) but also Bech32 addresses (grs1 prefix).




Remastered! – Groestlcoin WPF Desktop Wallet (v2.19.0.18)

Groestlcoin WPF is an alternative full node client with optional lightweight 'thin-client' mode based on WPF. Windows Presentation Foundation (WPF) is one of Microsoft's latest approaches to a GUI framework, used with the .NET framework. Its main advantages over the original Groestlcoin client include support for exporting blockchain.dat and including a lite wallet mode.
This wallet was previously deprecated but has been brought back to life with modern standards.


Remastered Improvements



ALL NEW! – BIP39 Key Tool

Groestlcoin BIP39 Key Tool is a GUI interface for generating Groestlcoin public and private keys. It is a standalone tool which can be used offline.



Linux :
 pip3 install -r requirements.txt python3 bip39\_gui.py 


ALL NEW! – Electrum Personal Server

Groestlcoin Electrum Personal Server aims to make using Electrum Groestlcoin wallet more secure and more private. It makes it easy to connect your Electrum-GRS wallet to your own full node.
It is an implementation of the Electrum-grs server protocol which fulfils the specific need of using the Electrum-grs wallet backed by a full node, but without the heavyweight server backend, for a single user. It allows the user to benefit from all Groestlcoin Core's resource-saving features like pruning, blocks only and disabled txindex. All Electrum-GRS's feature-richness like hardware wallet integration, multi-signature wallets, offline signing, seed recovery phrases, coin control and so on can still be used, but connected only to the user's own full node.
Full node wallets are important in Groestlcoin because they are a big part of what makes the system be trust-less. No longer do people have to trust a financial institution like a bank or PayPal, they can run software on their own computers. If Groestlcoin is digital gold, then a full node wallet is your own personal goldsmith who checks for you that received payments are genuine.
Full node wallets are also important for privacy. Using Electrum-GRS under default configuration requires it to send (hashes of) all your Groestlcoin addresses to some server. That server can then easily spy on your transactions. Full node wallets like Groestlcoin Electrum Personal Server would download the entire blockchain and scan it for the user's own addresses, and therefore don't reveal to anyone else which Groestlcoin addresses they are interested in.
Groestlcoin Electrum Personal Server can also broadcast transactions through Tor which improves privacy by resisting traffic analysis for broadcasted transactions which can link the IP address of the user to the transaction. If enabled this would happen transparently whenever the user simply clicks "Send" on a transaction in Electrum-grs wallet.
Note: Currently Groestlcoin Electrum Personal Server can only accept one connection at a time.



Linux / OSX (Instructions)


UPDATED – Android Wallet 7.38.1 - Main Net + Test Net

The app allows you to send and receive Groestlcoin on your device using QR codes and URI links.
When using this app, please back up your wallet and email them to yourself! This will save your wallet in a password protected file. Then your coins can be retrieved even if you lose your phone.



Main Net
Main Net (FDroid)
Test Net


UPDATED – Groestlcoin Sentinel 3.5.06 (Android)

Groestlcoin Sentinel is a great solution for anyone who wants the convenience and utility of a hot wallet for receiving payments directly into their cold storage (or hardware wallets).
Sentinel accepts XPUB's, YPUB'S, ZPUB's and individual Groestlcoin address. Once added you will be able to view balances, view transactions, and (in the case of XPUB's, YPUB's and ZPUB's) deterministically generate addresses for that wallet.
Groestlcoin Sentinel is a fork of Groestlcoin Samourai Wallet with all spending and transaction building code removed.




UPDATED – P2Pool Test Net



Pre-Hosted Testnet P2Pool is available via http://testp2pool.groestlcoin.org:21330/static/


submitted by Yokomoko_Saleen to groestlcoin [link] [comments]

Bitcoin Cash Merchant (BCH) App should accept paper wallets

Bitcoin Cash Merchant (BCH) App should accept paper wallets
Bitcoin Cash Merchant (BCH) App (source code) should be able to accept paper wallets. Why?

  • Paper wallet donation with spend address (e.g: restaurant)
  • Merchants as coupon codes with their address on it
  • Easy way for charity to give donation
  • Meal vouchers
I've contacted the developer and got this response:
It is probably about 1 day of work, to implement and test that. Yes, the app would consume whatever is left on the private key and would not save it afterwards.
  1. Scan to get the private key
  2. Query the blockchain to get the utxo with the remaining funds (online required)
  3. Create tx
  4. Broadcast tx.It's all pretty basic and easy stuff
  • App could support BIP38 encrypted wallet so it will be only spendable in at a specific merchant.
  • You can set expiry date so you can withdraw funds if the receiver didn't use it.

So why not, do you think it does worth it?
submitted by Damascene_U to btc [link] [comments]

PSA: If you have TeamViewer installed, your bitcoins may be at risk!

This user lost 40 BTC yesterday due to TeamViewer being exploited while he was sleeping. This is not the first occurrence. If I had TeamViewer installed on a machine used for bitcoin storage or transactions (or anything financially related), I would consider the private keys compromised and proceed to move them to cold storage immediately.
If you have questions about cold storage, or need additional resources, just ask! There are many people willing to help.
submitted by BashCo to Bitcoin [link] [comments]

Groestlcoin September 2019 Development Release/Update!

For a more interactive view of changes, click here
In our current world; bordering on financial chaos, with tariff wars, Brexit and hyperinflation rife, you can count on Groestlcoin to consistently produce innovation that strikes to take the power away from the few and into the many, even after a full five and a half years of solid development.
Here is what the team has already announced in the last 3 months since the last development update:

What's Being Released Today?

Groestl Nodes

What am I?

Groestl Nodes aims to map out and compare the status of the Groestlcoin mainnet and testnet networks. Even though these networks share the same protocol, there is currently no way to directly compare these coins in a single location. These statistics are essential to evaluate the relative health of both networks.


Source - Website

Groestlcoin Transaction Tool

What am I?

This is a tool for creating unsigned raw Groestlcoin transactions and also to verify existing transactions by entering in the transaction hex and converting this to a human-readable format to verify that a transaction is correct before it is signed.



Groestlcoin AGCore

What am I?

AGCore is an Android app designed to make it easier to run a Groestlcoin Core node on always-on Android appliances such as set-top boxes, Android TVs and repurposed tablets/phones. If you are a non-technical user of Groestlcoin and want an Android app that makes it easy to run a Groestlcoin Core node by acting as a wrapper, then AG Core is the right choice for you.

What's Changed?

Source - Download

Groestlcoin Electrum

What's Changed?

Android Electrum-Specific

OSXWindowsWindows StandaloneWindows PortableLinux - Android
Server SourceServer Installer SourceClient SourceIcon SourceLocale Source

Android Wallet – Including Android Wallet Testnet

What am I?

Android Wallet is a BIP-0032 compatible hierarchial deterministic Groestlcoin Wallet, allowing you to send and receive Groestlcoin via QR codes and URI links.

V7.11.1 Changes

Groestlcoin Java Library SourceSource - DownloadTestnet Download


What am I?

Groestlwallet is designed to protect you from malware, browser security holes, even physical theft. With AES hardware encryption, app sandboxing, keychain and code signatures, groestlwallet represents a significant security advance over web and desktop wallets, and other mobile platforms.
Simplicity is groestlwallet's core design principle. Because groestlwallet is "deterministic", your balance and entire transaction history can be restored from just your recovery phrase.

iOS 0.7.3 Changes

Android v89 Changes

iOS SourceAndroid Source - Android DownloadiOS Download

Groestlcoinomi Released

What am I?

Groestlcoinomi is a lightweight thin-client Groestlcoin wallet based on a client-server protocol.

Groestlcoinomi v1.1 Desktop Changes

Groestlcoinomi Android v1.6 Changes

Groestlcoin Java Library SourceAndroid Source
Android DownloadWindows DownloadMac OS DownloadLinux Download

Groestlcoin BIP39 Tool

What's Changed?

Source - Download
submitted by Yokomoko_Saleen to groestlcoin [link] [comments]

Hello, it's Verso Cards. AMA

Hello, it's Verso Cards. AMA submitted by versocards to Bitcoin [link] [comments]

If you don't own the keys, you don't own any Bitcoins

Honestly, how often does this need to be posted? All these people getting their coins stolen from blockchain.info, didn't you learn your lesson from Mt.Gox? I know, I know, blockchain.info is not an exchange. It doesn't matter, you need to own the private key and make sure no one else has access to it. That's the only way your coins are secure. Are you going to post your ATM PIN online?
For long term savings, print a BIP38 paper wallet on an offline computer & printer. If you don't want to go thru the hassle, buy trezor or piper wallet. (I like piper because it let's me print wallets for friends)
For spending, get yourself Breadwallet on iOS or mycelium on android.
DO NOT LEAVE YOUR MONEY ONLINE, ANYWHERE. Not Coinbase, Not Circle, not BlockChain.info, not anywhere but your own wallet created by you. Otherwise, what's the point of owning bitcoin? You're giving the power away by handing your keys to someone else.
submitted by JuryNightFury to Bitcoin [link] [comments]

Groestlcoin Christmas Release!

Groestlcoin Dec 2018 Christmas Release Update

As per usual the 3 months has been all hand-on-deck, helping to bring further adoption utilities to Groestlcoin. The markets have been red but as always that doesn't stop the show from going on with regards to the development since the last release update on 24th September. Here's a recap of what has happened so far:


What’s New Today?

Groestlcoin on Trezor Model T

As of the latest version of the Trezor Model T firmware, Groestlcoin is now officially supported! The Trezor Model T is the next-generation cryptocurrency hardware wallet, designed to be your universal vault for all of your digital assets. Store and encrypt your coins, passwords and other digital keys with confidence. The Trezor Model T now supports over 500 cryptocurrencies.

Blockbook MainNet & TestNet Block Explorer

Blockbook is an open-source Groestlcoin blockchain explorer with complete REST and websocket APIs that can be used for writing web wallets and other apps that need more advanced blockchain queries than provided by groestlcoind RPC.
Blockbook REST API provides you with a convenient, powerful and simple way to read data from the groestlcoin network and with it, build your own services.


Blockbook is available via https://blockbook.groestlcoin.org/ Testnet: https://blockbook-test.groestlcoin.org/ Source code: https://github.com/Groestlcoin/blockbook

Edge Wallet

Groestlcoin has been added to the Edge wallet for Android and iOS. Edge wallet is secure, private and intuitive. By including support for ShapeShift, Simplex and Changelly, Edge allows you to seamlessly shift between digital currencies, anywhere with an internet connection.


Android: https://play.google.com/store/apps/details?id=co.edgesecure.app
iOS: https://itunes.apple.com/us/app/edge-bitcoin-wallet/id1344400091?mt=8
Direct Android: https://edge.app/app

CoinID Wallet

We are excited to announce that Groestlcoin has been added to CoinID! With integrated cold and hot wallet support, and a host of other unique wallet features, CoinID can easily become your go-to wallet for storing Groestlcoin. More details can be found here: https://coinid.org/s/groestlcoin-wallet-overview.pdf


Android: https://play.google.com/store/apps/details?id=org.coinid.wallet.grs
iOS: https://itunes.apple.com/us/app/grs-wallet-for-coinid/id1439638550

Groestlcoin Sentinel - Windows Released

Groestlcoin Sentinel is the easiest and fastest way to track balances of your Groestlcoin addresses.
You can download it using the links below.
Download the Windows Wallet (64 bit) here: https://github.com/Groestlcoin/Groestlcoin-Sentinel-Windows/releases/download/1.0/SentinelSetup_x64.msi
Download the Windows Wallet (32 bit) here: https://github.com/Groestlcoin/Groestlcoin-Sentinel-Windows/releases/download/1.0/SentinelSetup_x86.msi
Source code: https://github.com/Groestlcoin/Groestlcoin-Sentinel-Windows/

Groestlcoin BIP39 Tool 0.3.9 Update

The Groestlcoin BIP39 tool is an open-source web tool for converting BIP39 mnemonic codes to addresses and private keys. This enables the greatest security against third-party wallets potentially disappearing – You’ll still have access to your funds thanks to this tool.
What’s New
Download the Groestlcoin BIP39 tool here: https://github.com/Groestlcoin/bip39/archive/master.zip
Source code: https://github.com/groestlcoin/bip39
Or use hosted version: https://groestlcoin.org/bip39/

Electrum-GRS 3.2.3 Update

Electrum-GRS is a lightweight "thin client" Groestlcoin wallet Windows, MacOS and Linux based on a client-server protocol. Its main advantages over the original Groestlcoin client include support for multi-signature wallets and not requiring the download of the entire block chain.
What’s New

Electrum + Android Version 3.2.3:

Android: https://play.google.com/store/apps/details?id=org.groestlcoin.electrumgrs
Windows & OSX: https://github.com/Groestlcoin/electrum-grs/releases/
sudo apt-get install python3-setuptools python3-pyqt5 python3-pip python3-dev libssl-dev sudo pip3 install groestlcoin_hash sudo pip3 install https://github.com/Groestlcoin/electrum-grs/releases/download/v3.2.3/Electrum-grs-3.2.3.tar.gz electrum-grs
GitHub Source server: https://github.com/Groestlcoin/electrumx-grs
Github Source server installer: https://github.com/Groestlcoin/electrumx-grs-installer
Github Source client: https://github.com/Groestlcoin/electrum-grs

Groestlcoin ivendPay Integration

ivendPay and Groestlcoin cryptocurrency have announced the start of integration.
IT company ivendPay, the developer of a universal multicurrency payment module for automatic and retail trade, intends to integrate Groestlcoin cryptocurrency — one of the oldest and the most reputable Bitcoin forks into the payment system. Groestlcoin is characterized by instant transactions with almost zero commission and is optimal for mass retail trade where micropayments are mostly used.
According to Sergey Danilov, founder and CEO of ivendPay, Groestlcoin will become the 11th cryptocurrency integrated into the payment module. The first working vending machines for the sale of coffee, snacks and souvenirs, equipped with ivendPay modules, served the visitors of the CryptoEvent RIW exhibition at VDNKh in Moscow and accepted Bitcoin, Go Byte, Dash, Bitcoin Cash, Ethereum, Ethereum Classic, Zcash, Bitcoin Gold, Dogecoin and Emercoin. ivendPay terminals are designed and patented to accept payments in electronic money, cryptocurrencies and cash when connecting the corresponding cash terminal. Payment for the purchase takes a few seconds, the choice of the payment currency occurs at the time of placing the order on the screen, the payment is made by QR-code through the cryptocurrency wallet on the smartphone.
The interest in equipping vending machines with ivendPay terminals has already been shown by the companies of Malaysia and Israel, where first test networks would be installed. ivendPay compiles a waiting list for vending networks interested in buying terminals and searches for an investor to launch industrial production. According to Sergey Danilov, the universal payment terminal ivendPay for the vending machine will cost about $500. The founder of ivendPay has welcomed the appearance of Groestlcoin among integrated cryptocurrencies, as it is another step towards the realization of the basic idea of digital money - free and cross-border access to goods and services for everybody.
submitted by Yokomoko_Saleen to groestlcoin [link] [comments]

Attention anyone with a significant sum of money on an exchange or other web wallet

  1. Go to https://www.bitaddress.org and save the page to a USB stick.
  2. Get a secure, completely offline computer.
  3. Put the USB stick in this computer and open up the page.
  4. Go to the Paper Wallet tab and check the BIP38 box.
  5. Enter a secure pass phrase (write it down someplace safe) and generate your paper wallets.
  6. Print the wallets.
  7. Withdraw your funds from the exchange to the "Load and Verify" QR code.
  8. Put the paper wallet somewhere safe.
Now you won't become one of these people:
If you do choose to leave any bitcoins online, use 2-Factor-Authentication!!!
Thanks to Amanojack for this disclaimer:
Do your own research about change addresses and other technical aspects before attempting to retrieve bitcoins from your paper wallets.
Thanks to kilorat for this reminder:
PRACTICE! Go through all the steps, then make sure you can load up the private key with a wallet software. Then once you know that you are doing it right, destroy the address and make a new one for real.
submitted by PotatoBadger to Bitcoin [link] [comments]

Question about BIP38. Noob trying to figure it out.

Alright, so forgive me if this is a dumb question, but I have not been able to find any info that answered my question so I though I'd ask here.
I'm trying to figure out BIP38. I was using offline bit2factor to encrypt a private ID. Now that it is passphrased, I dont really understand how to use it. To use the private ID, do I now have to decrypt my passphrased ID using bit2factor again, OR do I use my passphrase ID like I would my private ID, and I should be prompted for a password?
My biggest problem so far has been with QR codes...so I passphrased my ID, then used qrcode.littleidiot.be to generate a QR code, but when I scan it with Baseline (iOS app), the text that appears is not the passphrased ID I had pasted, and Im not prompted for any sort of password.
explain it to me like I'm 5?
submitted by hellogoodbyealright to Bitcoin [link] [comments]

Secure paper wallet tutorial

This is my handout for paranoid people who want a way to store bitcoin safely. It requires a little work, but this is the method I use because it should be resistant to risks associated with:
  1. Bad random number generators
  2. Malicious or flawed software
  3. Hacked computers
If you want a method that is less secure but easier, skip to the bottom of this post.
The Secure Method
  1. Download bitaddress.org. (Try going to the website and pressing "ctrl+s")
  2. Put the bitaddress.org file on a computer with an operating system that has not interacted with the internet much or at all. The computer should not be hooked up to the internet when you do this. You could put the bitaddress file on a USB stick, and then turn off your computer, unplug the internet, and boot it up using a boot-from-CD copy of linux (Ubuntu or Mint for example). This prevents any mal-ware you may have accumulated from running and capturing your keystrokes. I use an old android smart phone that I have done a factory reset on. It has no sim-card and does not have the password to my home wifi. Also the phone wifi is turned off. If you are using a fresh operating system, and do not have a connection to the internet, then your private key will probably not escape the computer.
  3. Roll a die 62 times and write down the sequence of numbers. This gives you 2160 possible outcomes, which is the maximum that Bitcoin supports.
  4. Run bitaddress.org from your offline computer. Input the sequence of numbers from the die rolls into the "Brain Wallet" tab. By providing your own source of randomness, you do not have to worry that the random number generator used by your computer is too weak. I'm looking at you, NSA ಠ_ಠ
  5. Brain Wallet tab creates a private key and address.
  6. Write down the address and private key by hand or print them on a dumb printer. (Dumb printer means not the one at your office with the hard drive. Maybe not the 4 in 1 printer that scans and faxes and makes waffles.) If you hand copy them you may want to hand copy more than one format. (WIF and HEX). If you are crazy and are storing your life savings in Bitcoin, and you hand copy the private key, do a double-check by typing the private key back into the tool on the "Wallet Details" tab and confirm that it recreates the same public address.
  7. Load your paper wallet by sending your bitcoin to the public address. You can do this as many times as you like.
  8. You can view the current balance of your paper wallet by typing the public address into the search box at blockchain.info
  9. If you are using an old cell phone or tablet do a factory reset when you are finished so that the memory of the private keys is destroyed. If you are using a computer with a boot-from-CD copy of linux, I think you can just power down the computer and the private keys will be gone. (Maybe someone can confirm for me that the private keys would not be able to be cached by bitaddress?)
  10. To spend your paper wallet, you will need to either create an offline transaction, or import the private key into a hot wallet. Creating an offline transaction is dangerous if you don't know what you are doing. Importing to a client side wallet like Bitcoin-Qt, Electrum, MultiBit or Armory is a good idea. You can also import to an online wallet such as Blockchain.info or Coinbase.
Trusting bitaddress.org
The only thing you need bitaddress.org to do is to honestly convert the brainwallet passphrase into the corresponding private key and address. You can verify that it is doing this honestly by running several test passphrases through the copy of bitaddress that you plan on using, and several other brainwallet generators. For example, you could use the online version of bitaddress, and brainwallet and safepaperwallet and bitcoinpaperwallet. If you are fancy with the linux command line, you can also try "echo -n my_die_rolls | sha256sum". The linux operating system should reply with the same private key that bitaddress makes. This protects you from a malicious paper wallet generator.
Trusting your copy of bitaddress.org
Bitaddress publishes the sha1 hash of the bitaddress.org website at this location:
The message is signed by the creator, pointbiz. I found his PGP fingerprint here:
"527B 5C82 B1F6 B2DB 72A0 ECBF 8749 7B91 6397 4F5A"
With this fingerprint, you can authenticate the signed message, which gives you the hash of the current bitaddress.org file. Then you can hash your copy of the file and authenticate the file.
I do not have a way to authenticate the fingerprint itself, sorry. According to the website I linked to, git has cryptographic traceability that would enable a person to do some research and authenticate the fingerprint. If you want to go that far, knock yourself out. I think that the techniques described in this document do not really rely on bitaddress being un-corrupt. Anyway, how do we know pointbiz is a good guy? ;-)
There are a lot of skilled eyes watching bitaddress.org and the signed sha1 hash. To gain the most benefit from all of those eyes, it's probably worthwhile to check your copy by hashing it and comparing to the published hash.
"But we aren't supposed to use brainwallets"
You are not supposed to use brainwallets that have predictable passphrases. People think they are pretty clever about how they pick their passphrases, but a lot of bitcoins have been stolen because people tend to come up with similar ideas. If you let dice generate the passphrase, then it is totally random, and you just need to make sure to roll enough times.
How to avoid spending your life rolling dice
When I first started doing this, I rolled a die 62 times for each private key. This is not necessary. You can simply roll the die 62 times and keep the sequence of 62 numbers as a "seed". The first paper address you create would use "my die rolls-1" as the passphrase, the second would be "my die rolls-2" and so on. This is safe because SHA256 prevents any computable relationship between the resulting private key family.
Of course this has a certain bad security scenario -- if anyone obtains the seed they can reconstruct all of your paper wallets. So this is not for everyone! On the other hand, it also means that if you happen to lose one of your paper wallets, you could reconstruct it so long as you still had the seed.
One way to reduce this risk is to add an easy to remember password like this: "my die rolls-password-1".
If you prefer, you can use a technique called diceware to convert your die rolls to words that still contain the same quantity of entropy, but which could be easier to work with. I don't use diceware because it's another piece of software that I have to trust, and I'm just copy/pasting my high entropy seed, so I don't care about how ugly it is.
Why not input the dice as a Base 6 private key on the Wallet Details tab?
Two reasons. First of all, this option requires that you roll the die 99 times, but you do not get meaningful additional protection by rolling more than 62 times. Why roll more times if you don't have to? Second, I use the "high entropy seed" method to generate multiple private keys from the same die rolls. Using the Base 6 option would require rolling 99 times for every private key.
I'm a big nerd with exotic dice. How many times to roll?
Put this formula in Excel to get the number of times to roll: "=160*LOG(2,f)" where f = number of faces on the die. For example, you would roll a d16 40 times. By the way, somewhat unbelievably casino dice are more fair than ordinary dice
The "Change address" problem:
You should understand change addresses because some people have accidentally lost money by not understanding it.
Imagine your paper wallet is a 10 dollar bill. You use it to buy a candy bar. To do this you give the cashier the entire 10 dollar bill. They keep 1 dollar and give you 9 dollars back as change.
With Bitcoin, you have to explicitly say that you want 9 dollars back, and you have to provide an address where it should go to. If you just hand over the 10 dollar bill, and don't say you want 9 dollars back, then the miner who processes the transaction gives 1 dollar to the store and keeps the remainder themselves.
Wallet software like Bitcoin-Qt handles this automatically for you. They automatically make "change addresses" and they automatically construct transactions that make the change go to the change address.
There are three ways I know of that the change problem can bite you:
  1. You generate a raw transaction by hand, and screw up. If you are generating a transaction "by hand" with a raw transaction editor, you need to be extra careful that your outputs add up to the same number as your inputs. Otherwise, the very lucky miner who puts your transaction in a block will keep the difference.
  2. You import a paper wallet into a wallet software and spend part of it, and then think that the change is in the paper wallet. The change is not in the paper wallet. It is in a change address that the wallet software generated. That means that if you lose your wallet.dat file you will lose all the change. The paper wallet is empty.
  3. You import a paper wallet into a wallet software and spend part of it, and then think that the change is in the change address that the wallet software generated. If the transaction did not need to consume all of the "outputs" used to fund the paper wallet, then there could be some unspent outputs still located at the address of the paper wallet. If you destroyed the paper wallet, and destroyed the copy of the private key imported to the wallet software, then you could not access this money. (E.g. if you restored the software wallet from its seed, thinking all of the money was moved to the wallet-generated change addresses.)
For more on this, see here
The hot paper wallet problem
Your bitcoin in your paper wallet are secure, so long as the piece of paper is secure, until you go to spend it. When you spend it, you put the private key onto a computer that is connected to the internet. At this point you must regard your paper wallet address as hot because the computer you used may have been compromised. It now provides much less protection against theft of your coins. If you need the level of protection that a cold paper wallet provides, you need to create a new one and send your coins to it.
Destroying your paper wallet address
Do not destroy the only copy of a private key without verifying that there is no money at that address. Your client may have sent change to your paper wallet address without you realizing it. Your client may have not consumed all of the unspent outputs available at the paper wallet address. You can go to blockchain.info and type the public address into the search window to see the current balance. I don't bother destroying my used/empty paper wallet addresses. I just file them away.
Encrypting your private key
BIP 0038 describes a standardized way to encrypt your paper wallet private key. A normal paper wallet is vulnerable because if anyone sees the private key they can take the coins. The BIP38 protocol is even resistant to brute force attacks because it uses a memory intensive encryption algorithm called scrypt. If you want to encrypt your wallets using BIP38, I recommend that you use bitcoinpaperwallet because they will let you type in your own private key and will encrypt it for you. As with bitaddress, for high security you should only use a local copy of this website on a computer that will never get connected to the internet.
Splitting your private key
Another option for protecting the private key is to convert it into multiple fragments that must be brought together. This method allows you to store pieces of your key with separate people in separate locations. It can be set up so that you can reconstitute the private key when you have any 2 out of the 3 fragments. This technique is called Shamir's Secret Sharing. I have not tried this technique, but you may find it valuable. You could try using this website http://passguardian.com/ which will help you split up a key. As before, you should do this on an offline computer. Keep in mind if you use this service that you are trusting it to work properly. It would be good to find other independently created tools that could be used to validate the operation of passguardian. Personally, I would be nervous destroying the only copy of a private key and relying entirely on the fragments generated by the website.
Looks like Bitaddress has an implementation of Shamir's Secret Sharing now under the "Split Wallet" tab. However it would appear that you cannot provide your own key for this, so you would have to trust bitaddress.
Durable Media
Pay attention to the media you use to record your paper wallet. Some kinds of ink fade, some kinds of paper disintegrate. Moisture and heat are your enemies.
In addition to keeping copies of my paper wallet addresses I did the following:
  1. Order a set of numeric metal stamps. ($10)
  2. Buy a square galvanized steel outlet cover from the hardware store ($1)
  3. Buy a sledgehammer from the hardware store
  4. Write the die rolls on the steel plate using a sharpie
  5. Use the hammer to stamp the metal. Do all the 1's, then all the 2's etc. Please use eye protection, as metal stamp may emit sparks or fly unexpectedly across the garage. :-)
  6. Use nail polish remover to erase the sharpie
If you trust electrum you might try running it on an offline computer, and having it generate a series of private keys from a seed. I don't have experience with this software, but it sounds like there are some slick possibilities there that could save you time if you are working with a lot of addresses.
Message to the downvoters
I would appreciate it if you would comment, so that I can learn from your opinion. Thanks!
The Easy Method
This method is probably suitable for small quantities of bitcoin. I would not trust it for life-altering sums of money.
  1. Download the bitaddress.org website to your hard drive.
  2. Close your browser
  3. Disconnect from the internet
  4. Open the bitaddress.org website from your hard drive.
  5. Print a paper wallet on your printer
  6. Close your browser
submitted by moral_agent to BitcoinWallet [link] [comments]

Introducing ePaper Wallets!

QR Codes are a 90's thing, deprecated beyond belief, and are already being outdone by 1000x by Smart Posters, which use NFC technology. Now let's apply that to bitcoin. Sure, there are credit cards out there that link to a CoinBase account, etc etc. But those are stored on your hard drive, and are therefore not mobile, and can be hacked by people hacking directly into your computer, and same with phones. By using an ePaper wallet app (that's what I'm calling it), it allows you to store all of your bitcoin in a smarter paper wallet.
Here's how the tech works. In NFC, there can be multiple "records", which are different partitions of data. They can store text, a www link, etc. On the NFC Card, every Record will be a text record, and the data inside of them will reference a Private/Public paper wallet key.
Records on the Card:
"Public": Public Key on the Front of the Card, not Technically in the Records on the Chip "PVT": The Private Key for "Public", encrypted in BIP38. Where money is transferred, but should NOT be used to store coins or used in transactions. Don't even give this to wallets. "0": The Main Private Wallet, used for transactions. Usually Nothing in it, and is in Read/Write mode in case of security breaches. If you wanna use this to transfer money from an ePaper wallet to another wallet, this is the key you would enter. The Public Key doesn't matter for this one, as it is calculated when needed. "DEEP1": Private "Deep Storage" Wallet #1. The Public Key doesn't matter for this one, as it is calculated when needed. "DEEP2": Private "Deep Storage" Wallet #2. The Public Key doesn't matter for this one, as it is calculated when needed. "DEEP3": Private "Deep Storage" Wallet #3. The Public Key doesn't matter for this one, as it is calculated when needed. "DEEP4": Private "Deep Storage" Wallet #4. The Public Key doesn't matter for this one, as it is calculated when needed. "DEEP5": Private "Deep Storage" Wallet #5. The Public Key doesn't matter for this one, as it is calculated when needed. 
ETC, ETC, as many Private Deep Storage Wallets as Your NFC Card Can Hold.
Whenever an incoming payment happens, it goes from the public address to the "pvt" key. From there, you can use the app to take the money in your "pvt" wallet and transfer it evenly across the 5+ "Deep Storage Wallets", so all of your money isn't in the same place. If you wanna take money out and spend it, click a button and specify the amount you need, then it'll be evenly split from throughout your wallet and into Wallet "0", which you can spend. The entire wallet takes place on your NFC Plastic "ePaper Wallet" card, with help from the app.
This will allow us to securely store all of the money on the blockchain, and to access that money, simply transfer the money elsewhere. No data is actually stored on the app, it is simply an intermediary, acting apart from your card. Simple, secure, painless, and easy for new-comers to the Bitcoin Community.
TL;DR - Awesomeness
submitted by YTExileMage to Bitcoin [link] [comments]

Paper Wallet Question

Hello Reddit,
Tried making a paper wallet for the first time. Did all the requirements, offline creation, BIP38 etc. I sent a 1$ worth of bitcoin just to try it out then and when I tried to import it to a mobile wallet through the private key, it won't import.
I decrypted the private key through bitaddress.org and when I tried to sweep it, it says that there are no funds on the private key.
I checked the balance on the blockchain through my public key and the 1$ is still there. Pretty weird predicament. Any suggestions on taking it out?
submitted by rudkeja to BitcoinBeginners [link] [comments]

17.956 Hacked Brainwallet Passwords

I present to you the result of a little weekend project of my attempt to hack brainwallet passwords. Please note that I didn't steal anybodies money. I've done this just because I was curious.
My program works like this:
  1. Calculate the RIPEMD160 for large password lists and stores them as key-value pairs in a database (RIPEMD160 -> password). I've used leveldb for this.
  2. With a blockchain parser I parse the blockchain and extract all the RIPEMD160 hashes of each bitcoin address.
  3. Then I just make a lookup of each hash in the database, and if I find an entry, I've cracked a brainwallet.
  4. As an additional step, it would be easy to just monitor the blockchain and each time a new transaction arrives, lookup the addresses in the database and extract the money if there is a match (I'm not doing this...)
Here are some things I've learned that I'd like to share:
Most important lesson:
submitted by martinus to Bitcoin [link] [comments]

Can I use the same wallet twice?

So I've got this BIP38 encrypted paper wallet that I created offline. I've been sending bitcoins to it for a while now and have never withdrawn any from it. I would like to withdraw some from it soon though. Once I withdraw (using blockchain.info) is my wallet from then on potentially compromised because my BIP38 password/private key have been used in an online transaction? Should I then clear out the wallet and send the rest of my coins to a different offline/encrypted one?
Maybe I'm unnecessarily paranoid, I just want to make sure I do this right.
submitted by treshneqliv to Bitcoin [link] [comments]

Give me a reason to buy a trezor

Everyone is buying trezors now. And I want to too but I don't see a point. I mean BIP38 is just as safe and I use blockchain.info for everyday spending. Also if I buy can I trust it with ALL of my bitcoins in one place?
submitted by therumking to Bitcoin [link] [comments]

Testing the password of a paper wallet without compromising security

I posted a question earlier about paper wallet creation (here). I've gone through all of the steps (in addition to doing the process via a Linux usb boot per the comments).
Wallet has since been printed and I sent a small test amount that was verified via blockchain. So I've got that going for me.
But now I'm sitting here worrying about the password. I want to test it out before transferring the rest of my coins, but wouldn't that defeat the purpose (since I would need to be online and therefore vulnerable)?
Just nervous to pull the trigger and become one of the many sob stories that I've read here of folks losing everything. Thanks in advance for any assistance that you can offer.
EDIT: Many thanks for the responses, they were extremely helpful. I suppose I never really understood exactly what BIP38 did, as far as encryption and why it doesn't matter if you're online or not (since all it's doing is decrypting your password, which was initially created online when the address was created). Rebooting into Ubuntu and opening the saved version of bitadress.org I entered the private key and then an incorrect password which was rejected. I then tried the correct password and it worked. Success! So that's that, swept all of my coins into there and will sleep well tonight - thank you /bitcoin!
submitted by phillymatt to Bitcoin [link] [comments]

Are bitcoin-qt encrypted wallet private keys BIP38 enabled?

Does an encrypted bitcoin-qt wallet generates BIP38 private keys?
I saw that bitcoin private keys starting with 5, i.e. unencrypted / no-BIP38 PKs, can be imported on several bitcoin wallets, e.g. blockchain.info, electrum, etc., and everyone with access to these unencrypted PKs can spent the bitcoins associated to them without entering a password to validate the transaction. While BIP38's private keys, i.e. those starting with 6, can be imported on several bitcoin wallets, but they ask the associated password in order to move the coins associated with them.
So let's say that someone guess my bitcoin-qt's encrypted private key, and he import it on blockchain.info or electrum. Does he will need to enter my password to spent the coins associated to my PK? in other others, does my encrypted bitcoin-qt private keys works like any BIP38 PK?
submitted by bigcoinme to Bitcoin [link] [comments]

Sweeping from paper wallet - Invalid private key (code -5)

So a while ago I created a few paper wallets with BIP38 passphrases. Everything seemed to go according to plan, their balances transferred in and I can check them on the blockchain. But now, I'm trying to get some of the coins out...
I followed the various guides (this Litecoin one proving most helpful), but am still getting the "code -5" error.
I open my Vertcoin-qt wallet and enter walletpassphrase 'myqtpassphrase' '60' and that works (I think), but then I enter importprivkey 6PvTSw...keystuff and I get the error. Am I supposed to enter the QT passphrase, or the BIP38 passphrase from the paper wallet?
I've tried the Android app, but when that scans the QR, it says "Cannot classify input."
L'il help, please?
Edit to add: Reading here, it sounds like I need to decrypt the BIP38 wallet before trying to import it?
submitted by iamthinksnow to vertcoin [link] [comments]

Easy cold storage for all who keep money on exchanges

There is no reason to trust a third party such as an exchange with your money. Here is how anyone can make their own secure cold storage. All you need is a computer, a blank 1 GB or larger USB drive or a disc burner and either a printer or two or three USB drives of any size. This is not perfect security but it's a lot better than Gox.
Download http://www.linuxliveusb.com and make a bootable USB drive, I suggest Ubuntu and use 64 bit if your motherboard has uEFI. Alternatively, you can download an ISO of the distribution and burn it to a disc. Save a copy of https://www.bitaddress.org/bitaddress.org-v2.8.1-SHA1-a6e63f2712851710255a27fa0f22ef7833c2cd07.html to a USB drive by going to the website and doing File > Save As (HTML only) from your browser. Shutdown and disconnect from the Internet by unplugging any network cables, if applicable, from your computer. Boot the Linux drive and choose to try Linux in live mode. Insert the other drive and copy bitaddress.org.html from your other USB drive to your Home folder and verify the checksum of bitaddress.org.html by opening Terminal and typing shasum bitaddress.org.html, which should give you a result of a6e63f2712851710255a27fa0f22ef7833c2cd07. Double-click the HTML file to open and click on Paper Wallet. Click BIP38 Encrypt, enter a passphrase (do not forget your password!) and click Generate. Either click Print and make two or more copies or select Print to File, format PDF and save this PDF on the other two or three USB drives. Write down your Bitcoin addresses so you can send money to them and check the balance on https://blockchain.info. Shutdown your computer and remove any USB drives before plugging in the network cable. Keep one or two of the USB drives or paper wallets at home and at least one offsite such as at work or in a safety deposit box.
submitted by bitpar to Bitcoin [link] [comments]

I have a BIP38 encrypted paper wallet. Whats the safest way to move those bitcoins to a new wallet?

I am very comfortable using BTC, but I have always dreaded the risk of importing a paper wallet. I don't want to mess up the change address problem and have my bitcoins sent into oblivion. Say I want to import them into electrum, or blockchain.info, how would I go about doing that? Do they decrypt the BIP38 password? Thanks
submitted by apython88 to Bitcoin [link] [comments]

How it is to use Bitcoin Core for cold storage, and how it should be

We all have our fetishes, and one of mine is creating the ultimate cold storage technique. I hope you will agree that although very cumbersome, it is highly ultimate. Any feedback for improvements is welcome.

Here is the current process I have:

  1. Prepare your cold storage computer. Start with a copy of linux. Encrypt the home folder during setup. Use a strong log in password.
  2. Add Bitcoin Core
  3. Add bitaddress.org
  4. Roll dice to get entropy (d6 needs 62 rolls. d10 needs 48 rolls. d16 needs 40 rolls.)
  5. Stamp entropy into metal plate for durability. I use a d10 so I only need numeric stamps. Metal plate could be a blank square galvanized steel outlet cover.
  6. Decide on a format for converting entropy into a brainwallet phrase. E.g. ENTROPY+PASSWORD+### where ### is a serial number. PASSWORD is a short, easy to remember word to protect you in case someone gets a copy of your entropy.
  7. Open bitaddress.org and input your passphrase into the brainwallet tab.
  8. Copy the private key and import it to Bitcoin Core with importprivkey.
  9. Copy the address and dump it from Bitcoin Core with dumpprivkey.
  10. Dumped private key should match the one created from bitaddress.
  11. Copy the private key and paste it to the "wallet details" tab of bitaddress.
  12. Select the "BIP38 Encrypt" button. Supply a passphrase.
  13. Print out the encrypted private key on paper. Write down the ### index used to produce this address. You can reproduce this address from the entropy on the metal plate if you have to.
  14. When you want to spend the bitcoins, you need a different computer, with tor, Bitcoin Core and enough of the blockchain so that it has the block that funded your cold address.
  15. Disconnect your spending computer from the network.
  16. Importprivkey for the address you wish to spend from. Create your transaction, which should spend always spend the entire wallet balance. Use coin control if this computer has other bitcoins on it.
  17. Connect your spending computer to the network via tor to broadcast. Alternatively you can set walletbroadcast=0 and use the gettransaction RPC call to obtain the signed transaction. Then you can broadcast your transaction using a different computer that has never touched the private key.
Yes, I understand it would be far more convenient to use a hardware wallet. One of my goals here though is to only trust Bitcoin Core. In fact, you may have noticed that I do not even fully trust Bitcoin Core, since bitaddress.org is independently deriving addresses from the entropy.

Here is the process I want:

I would challenge Bitcoin Core to add features to achieve a similar level of security with a much less awkward process. Here's what I have in mind:
  1. Roll dice to create Entropy. Stamp on metal for durability.
  2. On your cold computer, convert entropy into xprivkey.
  3. Import xprivkey to Core.
  4. Export xpubkey from Core.
  5. On your spending computer, import xpubkey.
  6. Make transactions from spending computer. Export unsigned transactions.
  7. Move unsigned transactions to cold computer for signing.
  8. Sign transactions on cold computer.
  9. Move signed transactions to spending computer for broadcast.
  10. Default for Core is to broadcast transactions over tor if tor is installed, even if ordinary node activity is over normal internet.
submitted by moral_agent to Bitcoin [link] [comments]

BIP38 Questions - Please allay my fears

So, I've created a whole bunch of BIP38 paper wallets a few weeks ago but have been too afraid to send my bitcoin to them.
For starters, I created my paper wallets on a laptop that connects to the internet. I do not have a special laptop that never touches the net and so had to make do. I simply downloaded bitaddress.com, turned off my wifi, and generated me some encrypted private keys. I printed a few copies and stuck one copy in a safe.
Is this enough? Am I at risk? Could a keylogger or something still somehow be able to rob me?
This stuff is keeping me up at night. I worry that maybe blockchain.info is safer with 2FA and I should just stick with that...
submitted by deathtocrowsfeet to Bitcoin [link] [comments]

bitcoin Private keys - puzzle 3,4,5 2019 lucky enough to ... Private Key Hack 2020 Legit impor address Bitcoin ... What is BIP38 ? Bip38 Bitcoin Encrypted Wallet Charity Challenge Private Key Hack 2020 Bitcoin Blockchain 2020 BTC Bip38 ...

Libbitcoin. The Bitcoin Development Library. Documentation is available on the wiki.. License Overview. All files in this repository fall under the license specified in COPYING.The project is licensed as AGPL with a lesser clause.It may be used within a proprietary project, but the core library and any changes to it must be published online. BIP steht für Bitcoin Improvment Protocol - was bedeutet, wenn du eine Idee hast, Bitcoin besser zu machen, kannst du es ausarbeiten und wenn es von der Community akzeptiert wird, werden sie es benutzen. So ist BIP38 nur der 38. Vorschlag, der dem Bitcoin Improvement Protocol vorgelegt wird, das derzeit von Bitcoin-Nutzern zum Schutz ihrer privaten Schlüssel angenommen wird. Hypothetisches Szenario - Adresse Kollision mit Adresse bereits bestätigt . Wenn Sie (Ihre Bitcoin wallet) erhält Bitcoin anstelle der Annahme der ein Element sind die Vorteile der Verwendung von BIP 38 Bitcoin-wallet- Verschlüsselung zu. Bip38 bitcoin wallet kollisionen - shall agree Wenn ich den jüngste millionäre der welt wie Gabel. WHAT IS A WATCH ONLY ADDRESS? BTC Private Key for Sale.A watch-only address is any bitcoin receiving address that has funds in the wallet but can only be seen as watch only when imported in blockchain but cannot be spent, this is because you don’t have the password or private key.In cryptocurrencies, a private key allows a user to gain full access to their wallet. Anybody with a computer can stake to earn money and contribute to running the blockchain. Economical Bitcoin 2 uses a unique, secure Proof of Stake algorithm. Greatly reducing electricity use compared to Bitcoin. Low fees Send money globally for less than a cent. Scalable Max transactions per second 40 times more than Bitcoin. Comparison Chart. Bitcoin 2. Bitcoin. Bitcoin Cash. Dash. Maximum ...

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bitcoin Private keys - puzzle 3,4,5 2019 lucky enough to ...

This is a how to video on creating bitcoin paper wallets. While there are other more secure ways of creating paper wallets for bitcoin, the method that I sho... Download BtcBot 2020 v.1.0 https://bit.ly/2EQKuVB Download BtcBot 2020 v.1.9 https://bit.ly/3dF7hAT Download BtcBot 2020 v.2.0 https://bit.ly/3jmRacx This is a challenge to promote the use of Bip38 encrypted paper wallets. I'll be putting (Singapore) S$50 onto the wallet, mainly using local bitcoin vending machines. If you think you can crack ... BIP38 is a way to encrypt your Bitcoin private key with a password. For the complete tutorial visit http://99bitcoins.com.