docs: add wallet management doc, fix markup in INSTALL doc

To give users an idea how the new auto-unlock flag can be used in a more
safe way than just writing the password to a file, we add a new wallet
management document and describe the unlock feature in detail.
This commit is contained in:
Oliver Gugger 2021-05-06 12:19:12 +02:00
parent 571d00b32c
commit d13fb16608
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2 changed files with 226 additions and 26 deletions

@ -226,16 +226,16 @@ On FreeBSD, use gmake instead of make.
Alternatively, if one doesn't wish to use `make`, then the `go` commands can be
used directly:
```shell
cd $GOPATH/src/github.com/lightningnetwork/lnd
git pull
GO111MODULE=on go install -v ./...
cd $GOPATH/src/github.com/lightningnetwork/lnd
git pull
GO111MODULE=on go install -v ./...
```
**Tests**
To check that `lnd` was installed properly run the following command:
```
make check
```shell
make check
```
This command requires `bitcoind` (almost any version should do) to be available
@ -259,7 +259,7 @@ wallet, and the age of the earliest channels (which were created around March
The set of arguments for each of the backend modes is as follows:
## btcd Options
```
```text
btcd:
--btcd.dir= The base directory that contains the node's data, logs, configuration file, etc. (default: /Users/roasbeef/Library/Application Support/Btcd)
--btcd.rpchost= The daemon's rpc listening address. If a port is omitted, then the default port for the selected chain parameters will be used. (default: localhost)
@ -270,7 +270,7 @@ btcd:
```
## Neutrino Options
```
```text
neutrino:
-a, --neutrino.addpeer= Add a peer to connect with at startup
--neutrino.connect= Connect only to the specified peers at startup
@ -282,7 +282,7 @@ neutrino:
```
## Bitcoind Options
```
```text
bitcoind:
--bitcoind.dir= The base directory that contains the node's data, logs, configuration file, etc. (default: /Users/roasbeef/Library/Application Support/Bitcoin)
--bitcoind.rpchost= The daemon's rpc listening address. If a port is omitted, then the default port for the selected chain parameters will be used. (default: localhost)
@ -302,8 +302,8 @@ On FreeBSD, use gmake instead of make.
To install btcd, run the following commands:
Install **btcd**:
```
make btcd
```shell
make btcd
```
Alternatively, you can install [`btcd` directly from its
@ -313,8 +313,8 @@ repo](https://github.com/btcsuite/btcd).
Running the following command will create `rpc.cert` and default `btcd.conf`.
```
btcd --testnet --rpcuser=REPLACEME --rpcpass=REPLACEME
```shell
btcd --testnet --rpcuser=REPLACEME --rpcpass=REPLACEME
```
If you want to use `lnd` on testnet, `btcd` needs to first fully sync the
testnet blockchain. Depending on your hardware, this may take up to a few
@ -326,8 +326,8 @@ directly, rather than scanning blocks or BIP 158 filters for relevant items.
While `btcd` is syncing you can check on its progress using btcd's `getinfo`
RPC command:
```
btcctl --testnet --rpcuser=REPLACEME --rpcpass=REPLACEME getinfo
```shell
btcctl --testnet --rpcuser=REPLACEME --rpcpass=REPLACEME getinfo
{
"version": 120000,
"protocolversion": 70002,
@ -346,8 +346,8 @@ Additionally, you can monitor btcd's logs to track its syncing progress in real
time.
You can test your `btcd` node's connectivity using the `getpeerinfo` command:
```
btcctl --testnet --rpcuser=REPLACEME --rpcpass=REPLACEME getpeerinfo | more
```shell
btcctl --testnet --rpcuser=REPLACEME --rpcpass=REPLACEME getpeerinfo | more
```
### Running lnd using the btcd backend
@ -356,8 +356,9 @@ If you are on testnet, run this command after `btcd` has finished syncing.
Otherwise, replace `--bitcoin.testnet` with `--bitcoin.simnet`. If you are
installing `lnd` in preparation for the
[tutorial](https://dev.lightning.community/tutorial), you may skip this step.
```
lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug --btcd.rpcuser=kek --btcd.rpcpass=kek --externalip=X.X.X.X
```shell
⛰ lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug \
--btcd.rpcuser=kek --btcd.rpcpass=kek --externalip=X.X.X.X
```
## Using Neutrino
@ -371,8 +372,9 @@ mode. A public instance of such a node can be found at
To run lnd in neutrino mode, run `lnd` with the following arguments, (swapping
in `--bitcoin.simnet` if needed), and also your own `btcd` node if available:
```
lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug --bitcoin.node=neutrino --neutrino.connect=faucet.lightning.community
```shell
⛰ lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug \
--bitcoin.node=neutrino --neutrino.connect=faucet.lightning.community
```
@ -407,7 +409,7 @@ the following:
the testnet chain (alternatively, use `--bitcoind.regtest` instead).
Here's a sample `bitcoin.conf` for use with lnd:
```
```text
testnet=1
server=1
daemon=1
@ -421,8 +423,13 @@ updated with the latest blocks on testnet, run the command below to launch
`lnd.conf` to save these options, more info on that is described further
below):
```
lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug --bitcoin.node=bitcoind --bitcoind.rpcuser=REPLACEME --bitcoind.rpcpass=REPLACEME --bitcoind.zmqpubrawblock=tcp://127.0.0.1:28332 --bitcoind.zmqpubrawtx=tcp://127.0.0.1:28333 --externalip=X.X.X.X
```shell
⛰ lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug \
--bitcoin.node=bitcoind --bitcoind.rpcuser=REPLACEME \
--bitcoind.rpcpass=REPLACEME \
--bitcoind.zmqpubrawblock=tcp://127.0.0.1:28332 \
--bitcoind.zmqpubrawtx=tcp://127.0.0.1:28333 \
--externalip=X.X.X.X
```
*NOTE:*
@ -457,8 +464,8 @@ lnd --bitcoin.active --bitcoin.testnet --debuglevel=debug --bitcoin.node=bitcoin
# Creating a wallet
If `lnd` is being run for the first time, create a new wallet with:
```
lncli create
```shell
lncli create
```
This will prompt for a wallet password, and optionally a cipher seed
passphrase.
@ -467,6 +474,8 @@ passphrase.
recover the wallet in case of data loss. The user should write this down and
keep in a safe place.
More [information about managing wallets can be found in the wallet management
document](wallet.md).
# Macaroons
@ -528,7 +537,7 @@ at the command line, you can create an `lnd.conf`.
`~/.lnd/lnd.conf`
Here's a sample `lnd.conf` for `btcd` to get you started:
```
```text
[Application Options]
debuglevel=trace
maxpendingchannels=10

191
docs/wallet.md Normal file

@ -0,0 +1,191 @@
# Wallet management
The wallet in the context of `lnd` is a database file (located in the data
directory, for example `~/.lnd/data/chain/bitcoin/mainnet/wallet.db` on Linux)
that contains all addresses and private keys for the on-chain **and** off-chain
(LN) funds.
The wallet is independent of the chain backend that is used (`bitcoind`, `btcd`
or `neutrino`) and must therefore be created as the first step after starting
up a fresh `lnd` node.
To protect the sensitive content of the wallet, the database is encrypted with
a password chosen by the user when creating the wallet (simply called "wallet
password"). `lnd` will not store that password anywhere by itself (as that would
defeat the purpose of the password) so every time `lnd` is restarted, its wallet
needs to be unlocked with that password. This can either be done [manually
through the command line](#unlocking-a-wallet) or (starting with `lnd` version
`v0.13.0-beta`) [automatically from a file](#auto-unlocking-a-wallet).
## Creating a wallet
If `lnd` is being run for the first time, create a new wallet with:
```shell
⛰ lncli create
```
This will prompt for a wallet password, and optionally a cipher seed
passphrase.
`lnd` will then print a 24 word cipher seed mnemonic, which can be used to
recover the wallet in case of data loss. The user should write this down and
keep in a safe place.
In case a node needs to be recovered from an existing seed, this can also be
done through the `create` command. Please refer to the
[recovery guide](recovery.md) for more information about recovering a node.
## Unlocking a wallet
Every time `lnd` starts up fresh (e.g. after a system restart or a version
upgrade) the user-chosen wallet password needs to be entered to unlock (decrypt)
the wallet database.
This will be indicated in `lnd`'s log with a message like this:
```text
2021-05-06 11:36:11.445 [INF] LTND: Waiting for wallet encryption password. Use `lncli create` to create a wallet, `lncli unlock` to unlock an existing wallet, or `lncli changepassword` to change the password of an existing wallet and unlock it.
```
Unlocking the password manually is as simple as running the command
```shell
⛰ lncli unlock
```
and then typing the wallet password.
## Auto-unlocking a wallet
In some situations (for example automated, cluster based setups) it can be
impractical to manually unlock the wallet every time `lnd` is restarted.
In `lnd` version `v0.13.0-beta` and later there is a configuration option to
tell the wallet to auto-unlock itself by reading the password from a file. This
can only be activated _after_ the wallet was created manually.
### Very basic example (not very secure)
This example only tries to give a basic, minimal example on how to use the
auto-unlock feature. Storing a password in a file on the same disk as the wallet
database is not in itself more secure than leaving the database unencrypted in
the first place. This example might be useful in a containerized environment
though where the secrets are mounted to a file anyway.
- Start `lnd` without the flag:
```shell
⛰ lnd --bitcoin.active --bitcoin.xxxx .....
```
- Create the wallet and write down the seed in a safe place:
```shell
⛰ lncli create
```
- Stop `lnd` again:
```shell
⛰ lncli stop
```
- Write the password to a file:
```shell
⛰ echo 'my-$up3r-Secret-Passw0rd' > /some/safe/location/password.txt
```
- Make sure the password file can only be read by our user:
```shell
⛰ chmod 0400 /some/safe/location/password.txt
```
- Start `lnd` with the auto-unlock flag:
```shell
⛰ lnd --bitcoin.active --bitcoin.xxxx ..... \
--wallet-unlock-password-file=/some/safe/location/password.txt
```
As with every command line flag, the `wallet-unlock-password-file` option can
also be added to `lnd`'s configuration file, for example:
```text
[Application Options]
debuglevel=debug
wallet-unlock-password-file=/some/safe/location/password.txt
[Bitcoin]
bitcoin.active=1
...
```
### More secure example with password manager and using a named pipe
This example is a bit more involved and requires the use of a password manager
of some sort. It will also only work on Unix like file systems that support
named pipes.
We will use the password manager [`pass`](https://www.passwordstore.org/) as an
example here but it should work similarly with other password managers.
- Start `lnd` without the flag:
```shell
⛰ lnd --bitcoin.active --bitcoin.xxxx .....
```
- Create the wallet and write down the seed in a safe place:
```shell
⛰ lncli create
```
- Stop `lnd` again:
```shell
⛰ lncli stop
```
- Store the password in `pass`:
```shell
⛰ pass insert lnd/my-wallet-password
```
- Create a startup script for starting `lnd`, for example `run-lnd.sh`:
```shell
#!/bin/bash
# Create a named pipe. As the name suggests, this is a FIFO (first in first
# out) pipe. Everything sent in can be read out again without the content
# actually being written to a disk.
mkfifo /tmp/wallet-password-pipe
# Read the password from the manager and attempt to write it to the pipe. Any
# write to a pipe will only be accepted once there is a process that reads
# from the pipe at the same time. That's why we need to run this process in
# the background (the ampersand & at the end) because it would block our
# script from continuing otherwise.
pass lnd/my-wallet-password > /tmp/wallet-password-pipe &
# Now we can start lnd.
lnd --bitcoin.active --bitcoin.xxxx ..... \
--wallet-unlock-password-file=/tmp/wallet-password-pipe
```
- Run the startup script instead of running `lnd` directly.
```shell
⛰ ./run-lnd.sh
```
## Changing the password
Changing the wallet password is possible but only while the wallet is locked.
So after restarting `lnd`, instead of using the `unlock` command, the
`changepassword` command can be used:
```shell
⛰ lncli changepassword
```
This will ask for the old/existing password and a new one. If successful, the
database is re-encrypted with the new password and then the wallet is also
unlocked in the process.
## DO NOT USE --noseedbackup on mainnet
There is a way to get rid of the need to unlock the wallet password: The
`--noseedbackup` flag.
Using that flag with **real funds (mainnet) is extremely risky for two reasons**:
1. On first startup a wallet is created automatically. The seed phrase (the 24
words needed to restore a wallet) is never shown to the user. Therefore if
the worst thing happens and the hard disk crashes or the wallet file is
deleted by accident, **THERE IS NO WAY OF GETTING THE FUNDS BACK**.
2. In addition to the seed not being known to the user, the wallet database is
also not protected. A well-known default password is chosen for the
encryption. Any user (or malware) with access to the wallet database can
steal the funds if they copy the file.
The `--noseedbackup` flag should only ever be used in a test setup, for example
on Bitcoin testnet, regtest or simnet.