nix-bitcoin/modules/bitcoind.nix
2021-01-14 13:25:03 +01:00

399 lines
14 KiB
Nix

{ config, pkgs, lib, ... }:
with lib;
let
cfg = config.services.bitcoind;
inherit (config) nix-bitcoin-services;
secretsDir = config.nix-bitcoin.secretsDir;
configFile = pkgs.writeText "bitcoin.conf" ''
# We're already logging via journald
nodebuglogfile=1
${optionalString cfg.regtest ''
regtest=1
[regtest]
''}
${optionalString (cfg.dbCache != null) "dbcache=${toString cfg.dbCache}"}
prune=${toString cfg.prune}
${optionalString (cfg.sysperms != null) "sysperms=${if cfg.sysperms then "1" else "0"}"}
${optionalString (cfg.disablewallet != null) "disablewallet=${if cfg.disablewallet then "1" else "0"}"}
${optionalString (cfg.assumevalid != null) "assumevalid=${cfg.assumevalid}"}
# Connection options
${optionalString cfg.listen "bind=${cfg.address}"}
port=${toString cfg.port}
${optionalString (cfg.proxy != null) "proxy=${cfg.proxy}"}
listen=${if cfg.listen then "1" else "0"}
${optionalString (cfg.discover != null) "discover=${if cfg.discover then "1" else "0"}"}
${lib.concatMapStrings (node: "addnode=${node}\n") cfg.addnodes}
# RPC server options
rpcbind=${cfg.rpc.address}
rpcport=${toString cfg.rpc.port}
rpcconnect=${cfg.rpc.address}
${optionalString (cfg.rpc.threads != null) "rpcthreads=${toString cfg.rpcthreads}"}
rpcwhitelistdefault=0
${concatMapStrings (user: ''
${optionalString (!user.passwordHMACFromFile) "rpcauth=${user.name}:${passwordHMAC}"}
${optionalString (user.rpcwhitelist != [])
"rpcwhitelist=${user.name}:${lib.strings.concatStringsSep "," user.rpcwhitelist}"}
'') (builtins.attrValues cfg.rpc.users)
}
${lib.concatMapStrings (rpcallowip: "rpcallowip=${rpcallowip}\n") cfg.rpcallowip}
# Wallet options
${optionalString (cfg.addresstype != null) "addresstype=${cfg.addresstype}"}
# ZMQ options
${optionalString (cfg.zmqpubrawblock != null) "zmqpubrawblock=${cfg.zmqpubrawblock}"}
${optionalString (cfg.zmqpubrawtx != null) "zmqpubrawtx=${cfg.zmqpubrawtx}"}
# Extra options
${cfg.extraConfig}
'';
in {
options = {
services.bitcoind = {
enable = mkEnableOption "Bitcoin daemon";
address = mkOption {
type = types.str;
default = "127.0.0.1";
description = "Address to listen for peer connections.";
};
port = mkOption {
type = types.port;
default = 8333;
description = "Port to listen for peer connections.";
};
package = mkOption {
type = types.package;
default = config.nix-bitcoin.pkgs.bitcoind;
defaultText = "pkgs.blockchains.bitcoind";
description = "The package providing bitcoin binaries.";
};
extraConfig = mkOption {
type = types.lines;
default = "";
example = ''
par=16
logips=1
'';
description = "Additional configurations to be appended to <filename>bitcoin.conf</filename>.";
};
dataDir = mkOption {
type = types.path;
default = "/var/lib/bitcoind";
description = "The data directory for bitcoind.";
};
user = mkOption {
type = types.str;
default = "bitcoin";
description = "The user as which to run bitcoind.";
};
group = mkOption {
type = types.str;
default = cfg.user;
description = "The group as which to run bitcoind.";
};
rpc = {
address = mkOption {
type = types.str;
default = "127.0.0.1";
description = ''
Address to listen for JSON-RPC connections.
'';
};
port = mkOption {
type = types.port;
default = 8332;
description = "Port to listen for JSON-RPC connections.";
};
users = mkOption {
default = {};
example = {
alice.passwordHMAC = "f7efda5c189b999524f151318c0c86$d5b51b3beffbc02b724e5d095828e0bc8b2456e9ac8757ae3211a5d9b16a22ae";
bob.passwordHMAC = "b2dd077cb54591a2f3139e69a897ac$4e71f08d48b4347cf8eff3815c0e25ae2e9a4340474079f55705f40574f4ec99";
};
type = with types; loaOf (submodule ({ name, ... }: {
options = {
name = mkOption {
type = types.str;
default = name;
example = "alice";
description = ''
Username for JSON-RPC connections.
'';
};
passwordHMAC = mkOption {
type = types.str;
example = "f7efda5c189b999524f151318c0c86$d5b51b3beffbc02b724e5d095828e0bc8b2456e9ac8757ae3211a5d9b16a22ae";
description = ''
Password HMAC-SHA-256 for JSON-RPC connections. Must be a string of the
format <SALT-HEX>$<HMAC-HEX>.
'';
};
passwordHMACFromFile = mkOption {
type = lib.types.bool;
internal = true;
default = false;
};
rpcwhitelist = mkOption {
type = types.listOf types.str;
default = [];
description = ''
List of allowed rpc calls for each user.
If empty list, rpcwhitelist is disabled for that user.
'';
};
};
}));
description = ''
RPC user information for JSON-RPC connections.
'';
};
};
rpcthreads = mkOption {
type = types.nullOr types.ints.u16;
default = null;
description = "Set the number of threads to service RPC calls";
};
rpcallowip = mkOption {
type = types.listOf types.str;
default = [ "127.0.0.1" ];
description = ''
Allow JSON-RPC connections from specified source.
'';
};
regtest = mkOption {
type = types.bool;
default = false;
description = "Enable regtest mode.";
};
network = mkOption {
readOnly = true;
default = if cfg.regtest then "regtest" else "mainnet";
};
makeNetworkName = mkOption {
readOnly = true;
default = mainnet: regtest: if cfg.regtest then regtest else mainnet;
};
proxy = mkOption {
type = types.nullOr types.str;
default = if cfg.enforceTor then config.services.tor.client.socksListenAddress else null;
description = "Connect through SOCKS5 proxy";
};
listen = mkOption {
type = types.bool;
default = false;
description = ''
If enabled, the bitcoin service will listen.
'';
};
dataDirReadableByGroup = mkOption {
type = types.bool;
default = false;
description = ''
If enabled, data dir content is readable by the bitcoind service group.
Warning: This disables bitcoind's wallet support.
'';
};
sysperms = mkOption {
type = types.nullOr types.bool;
default = null;
description = ''
Create new files with system default permissions, instead of umask 077
(only effective with disabled wallet functionality)
'';
};
disablewallet = mkOption {
type = types.nullOr types.bool;
default = null;
description = ''
Do not load the wallet and disable wallet RPC calls
'';
};
dbCache = mkOption {
type = types.nullOr (types.ints.between 4 16384);
default = null;
example = 4000;
description = "Override the default database cache size in megabytes.";
};
prune = mkOption {
type = types.ints.unsigned;
default = 0;
example = 10000;
description = ''
Reduce storage requirements by enabling pruning (deleting) of old
blocks. This allows the pruneblockchain RPC to be called to delete
specific blocks, and enables automatic pruning of old blocks if a
target size in MiB is provided. This mode is incompatible with -txindex
and -rescan. Warning: Reverting this setting requires re-downloading
the entire blockchain. ("disable" = disable pruning blocks, "manual"
= allow manual pruning via RPC, >=550 = automatically prune block files
to stay under the specified target size in MiB)
'';
};
zmqpubrawblock = mkOption {
type = types.nullOr types.str;
default = null;
example = "tcp://127.0.0.1:28332";
description = "ZMQ address for zmqpubrawblock notifications";
};
zmqpubrawtx = mkOption {
type = types.nullOr types.str;
default = null;
example = "tcp://127.0.0.1:28333";
description = "ZMQ address for zmqpubrawtx notifications";
};
assumevalid = mkOption {
type = types.nullOr types.str;
default = null;
example = "00000000000000000000e5abc3a74fe27dc0ead9c70ea1deb456f11c15fd7bc6";
description = ''
If this block is in the chain assume that it and its ancestors are
valid and potentially skip their script verification.
'';
};
addnodes = mkOption {
type = types.listOf types.str;
default = [];
example = [ "ecoc5q34tmbq54wl.onion" ];
description = "Add nodes to connect to and attempt to keep the connections open";
};
discover = mkOption {
type = types.nullOr types.bool;
default = null;
description = "Discover own IP addresses";
};
addresstype = mkOption {
type = types.nullOr types.str;
default = null;
example = "bech32";
description = "What type of addresses to use";
};
cli = mkOption {
readOnly = true;
type = types.package;
default = pkgs.writeScriptBin "bitcoin-cli" ''
exec ${cfg.package}/bin/bitcoin-cli -datadir='${cfg.dataDir}' "$@"
'';
description = "Binary to connect with the bitcoind instance.";
};
enforceTor = nix-bitcoin-services.enforceTor;
};
};
config = mkIf cfg.enable {
environment.systemPackages = [ cfg.package (hiPrio cfg.cli) ];
services.bitcoind = mkMerge [
(mkIf cfg.dataDirReadableByGroup {
disablewallet = true;
sysperms = true;
})
{
rpc.users.privileged = {
passwordHMACFromFile = true;
};
rpc.users.public = {
passwordHMACFromFile = true;
rpcwhitelist = import ./bitcoind-rpc-public-whitelist.nix;
};
}
];
systemd.tmpfiles.rules = [
"d '${cfg.dataDir}' 0770 ${cfg.user} ${cfg.group} - -"
"d '${cfg.dataDir}/blocks' 0770 ${cfg.user} ${cfg.group} - -"
];
systemd.services.bitcoind = {
description = "Bitcoin daemon";
requires = [ "nix-bitcoin-secrets.target" ];
after = [ "network.target" "nix-bitcoin-secrets.target" ];
wantedBy = [ "multi-user.target" ];
preStart = let
extraRpcauth = concatMapStrings (name: let
user = cfg.rpc.users.${name};
in optionalString user.passwordHMACFromFile ''
echo "rpcauth=${user.name}:$(cat ${secretsDir}/bitcoin-HMAC-${name})"
''
) (builtins.attrNames cfg.rpc.users);
in ''
${optionalString cfg.dataDirReadableByGroup "chmod -R g+rX '${cfg.dataDir}/blocks'"}
cfg=$(
cat ${configFile};
${extraRpcauth}
${/* Enable bitcoin-cli for group 'bitcoin' */ ""}
printf "rpcuser=${cfg.rpc.users.privileged.name}\nrpcpassword="; cat "${secretsDir}/bitcoin-rpcpassword-privileged";
)
confFile='${cfg.dataDir}/bitcoin.conf'
if [[ ! -e $confFile || $cfg != $(cat $confFile) ]]; then
install -o '${cfg.user}' -g '${cfg.group}' -m 640 <(echo "$cfg") $confFile
fi
'';
postStart = ''
# Poll until bitcoind accepts commands. This can take a long time.
while ! ${cfg.cli}/bin/bitcoin-cli getnetworkinfo &> /dev/null; do
sleep 1
done
'';
serviceConfig = nix-bitcoin-services.defaultHardening // {
User = "${cfg.user}";
Group = "${cfg.group}";
ExecStart = "${cfg.package}/bin/bitcoind -datadir='${cfg.dataDir}'";
Restart = "on-failure";
UMask = mkIf cfg.dataDirReadableByGroup "0027";
ReadWritePaths = "${cfg.dataDir}";
} // (if cfg.enforceTor
then nix-bitcoin-services.allowTor
else nix-bitcoin-services.allowAnyIP)
// optionalAttrs (cfg.zmqpubrawblock != null || cfg.zmqpubrawtx != null) nix-bitcoin-services.allowAnyProtocol;
};
# Use this to update the banlist:
# wget https://people.xiph.org/~greg/banlist.cli.txt
systemd.services.bitcoind-import-banlist = {
description = "Bitcoin daemon banlist importer";
wantedBy = [ "bitcoind.service" ];
bindsTo = [ "bitcoind.service" ];
after = [ "bitcoind.service" ];
script = ''
cd ${cfg.cli}/bin
echo "Importing node banlist..."
cat ${./banlist.cli.txt} | while read line; do
if ! err=$(eval "$line" 2>&1) && [[ $err != *already\ banned* ]]; then
# unexpected error
echo "$err"
exit 1
fi
done
'';
serviceConfig = nix-bitcoin-services.defaultHardening // {
User = "${cfg.user}";
Group = "${cfg.group}";
ReadWritePaths = "${cfg.dataDir}";
} // nix-bitcoin-services.allowTor;
};
users.users.${cfg.user} = {
group = cfg.group;
description = "Bitcoin daemon user";
};
users.groups.${cfg.group} = {};
users.groups.bitcoinrpc = {};
nix-bitcoin.operator.groups = [ cfg.group ];
nix-bitcoin.secrets.bitcoin-rpcpassword-privileged.user = "bitcoin";
nix-bitcoin.secrets.bitcoin-rpcpassword-public = {
user = "bitcoin";
group = "bitcoinrpc";
};
nix-bitcoin.secrets.bitcoin-HMAC-privileged.user = "bitcoin";
nix-bitcoin.secrets.bitcoin-HMAC-public.user = "bitcoin";
};
}