nix-bitcoin/modules/bitcoind.nix
Erik Arvstedt 826245484e
make secrets dir location configurable
Users of the nix-bitcoin modules shouldn't be forced to add an extra
dir under root.
The secrets location is unchanged for the default node config.
2020-01-13 00:25:12 +01:00

317 lines
11 KiB
Nix

{ config, pkgs, lib, ... }:
with lib;
let
cfg = config.services.bitcoind;
inherit (config) nix-bitcoin-services;
pidFile = "${cfg.dataDir}/bitcoind.pid";
configFile = pkgs.writeText "bitcoin.conf" ''
${optionalString cfg.testnet "testnet=1"}
${optionalString (cfg.dbCache != null) "dbcache=${toString cfg.dbCache}"}
${optionalString (cfg.prune != null) "prune=${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"}"}
# Connection options
${optionalString (cfg.port != null) "port=${toString cfg.port}"}
${optionalString (cfg.proxy != null) "proxy=${cfg.proxy}"}
listen=${if cfg.listen then "1" else "0"}
# RPC server options
rpcport=${toString cfg.rpc.port}
${concatMapStringsSep "\n"
(rpcUser: "rpcauth=${rpcUser.name}:${rpcUser.passwordHMAC}")
(attrValues cfg.rpc.users)
}
${optionalString (cfg.rpcuser != null) "rpcuser=${cfg.rpcuser}"}
${optionalString (cfg.rpcpassword != null) "rpcpassword=${cfg.rpcpassword}"}
# ZMQ options
${optionalString (cfg.zmqpubrawblock != null) "zmqpubrawblock=${cfg.zmqpubrawblock}"}
${optionalString (cfg.zmqpubrawtx != null) "zmqpubrawtx=${cfg.zmqpubrawtx}"}
# Extra config options (from bitcoind nixos service)
${cfg.extraConfig}
'';
cmdlineOptions = concatMapStringsSep " " (arg: "'${arg}'") [
"-datadir=${cfg.dataDir}"
"-pid=${pidFile}"
];
hexStr = types.strMatching "[0-9a-f]+";
rpcUserOpts = { name, ... }: {
options = {
name = mkOption {
type = types.str;
example = "alice";
description = ''
Username for JSON-RPC connections.
'';
};
passwordHMAC = mkOption {
type = with types; uniq (strMatching "[0-9a-f]+\\$[0-9a-f]{64}");
example = "f7efda5c189b999524f151318c0c86$d5b51b3beffbc02b724e5d095828e0bc8b2456e9ac8757ae3211a5d9b16a22ae";
description = ''
Password HMAC-SHA-256 for JSON-RPC connections. Must be a string of the
format <SALT-HEX>$<HMAC-HEX>.
'';
};
};
config = {
name = mkDefault name;
};
};
in {
options = {
services.bitcoind = {
enable = mkEnableOption "Bitcoin daemon";
package = mkOption {
type = types.package;
default = pkgs.nix-bitcoin.bitcoind;
defaultText = "pkgs.blockchains.bitcoind";
description = "The package providing bitcoin binaries.";
};
extraConfig = mkOption {
type = types.lines;
default = "";
example = ''
par=16
rpcthreads=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.";
};
configFileOption = mkOption {
type = types.path;
default = configFile;
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 = {
port = mkOption {
type = types.ints.u16;
default = 8332;
description = "Port on which to listen for JSON-RPC connections.";
};
users = mkOption {
default = {};
example = {
alice.passwordHMAC = "f7efda5c189b999524f151318c0c86$d5b51b3beffbc02b724e5d095828e0bc8b2456e9ac8757ae3211a5d9b16a22ae";
bob.passwordHMAC = "b2dd077cb54591a2f3139e69a897ac$4e71f08d48b4347cf8eff3815c0e25ae2e9a4340474079f55705f40574f4ec99";
};
type = with types; loaOf (submodule rpcUserOpts);
description = ''
RPC user information for JSON-RPC connnections.
'';
};
};
rpcuser = mkOption {
type = types.nullOr types.str;
default = null;
description = "Username for JSON-RPC connections";
};
rpcpassword = mkOption {
type = types.nullOr types.str;
default = null;
description = "Password for JSON-RPC connections";
};
testnet = mkOption {
type = types.bool;
default = false;
description = "Whether to use the test chain.";
};
port = mkOption {
type = types.nullOr types.ints.u16;
default = null;
description = "Override the default port on which to listen for connections.";
};
proxy = mkOption {
type = types.nullOr types.str;
default = null;
description = "Connect through SOCKS5 proxy";
};
listen = mkOption {
type = types.bool;
default = false;
description = ''
If enabled, the bitcoin service will listen.
'';
};
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.nullOr (types.coercedTo
(types.enum [ "disable" "manual" ])
(x: if x == "disable" then 0 else 1)
types.ints.unsigned
);
default = null;
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";
};
cli = mkOption {
type = types.package;
readOnly = true;
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 ];
systemd.services.bitcoind = {
description = "Bitcoin daemon";
requires = [ "nix-bitcoin-secrets.target" ];
after = [ "network.target" "nix-bitcoin-secrets.target" ];
wantedBy = [ "multi-user.target" ];
preStart = ''
if ! test -e ${cfg.dataDir}; then
mkdir -m 0770 -p '${cfg.dataDir}'
fi
if ! test -e ${cfg.dataDir}/blocks; then
mkdir -m 0770 -p '${cfg.dataDir}/blocks'
fi
cp '${cfg.configFileOption}' '${cfg.dataDir}/bitcoin.conf'
chmod o-rw '${cfg.dataDir}/bitcoin.conf'
chown -R '${cfg.user}:${cfg.group}' '${cfg.dataDir}'
echo "rpcpassword=$(cat ${config.nix-bitcoin.secretsDir}/bitcoin-rpcpassword)" >> '${cfg.dataDir}/bitcoin.conf'
chmod -R g+rX '${cfg.dataDir}/blocks'
'';
# Wait until RPC port is open. This usually takes just a few ms.
postStart = ''
while ! { exec 3>/dev/tcp/127.0.0.1/${toString cfg.rpc.port}; } &>/dev/null; do
sleep 0.05
done
'';
serviceConfig = {
Type = "simple";
User = "${cfg.user}";
Group = "${cfg.group}";
ExecStart = "${cfg.package}/bin/bitcoind ${cmdlineOptions}";
PIDFile = "${pidFile}";
Restart = "on-failure";
# Hardening measures
PrivateTmp = "true";
ProtectSystem = "full";
NoNewPrivileges = "true";
PrivateDevices = "true";
MemoryDenyWriteExecute = "true";
# Permission for preStart
PermissionsStartOnly = "true";
} // nix-bitcoin-services.defaultHardening
// (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
# Poll until bitcoind accepts commands. This can take a long time.
while ! ./bitcoin-cli getnetworkinfo &> /dev/null; do
sleep 1
done
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 = {
User = "${cfg.user}";
Group = "${cfg.group}";
} // nix-bitcoin-services.defaultHardening
// nix-bitcoin-services.allowTor;
};
users.users.${cfg.user} = {
group = cfg.group;
description = "Bitcoin daemon user";
home = cfg.dataDir;
};
users.groups.${cfg.group} = {};
users.groups.bitcoinrpc = {};
nix-bitcoin.secrets.bitcoin-rpcpassword = {
user = "bitcoin";
group = "bitcoinrpc";
};
};
}