{ config, options, lib, pkgs, ... }: with lib; let cfg = config.services.neo4j; certDirOpt = options.services.neo4j.directories.certificates; isDefaultPathOption = opt: isOption opt && opt.type == types.path && opt.highestPrio >= 1500; sslPolicies = mapAttrsToList ( name: conf: '' dbms.ssl.policy.${name}.allow_key_generation=${boolToString conf.allowKeyGeneration} dbms.ssl.policy.${name}.base_directory=${conf.baseDirectory} ${optionalString (conf.ciphers != null) '' dbms.ssl.policy.${name}.ciphers=${concatStringsSep "," conf.ciphers} ''} dbms.ssl.policy.${name}.client_auth=${conf.clientAuth} ${if length (splitString "/" conf.privateKey) > 1 then ''dbms.ssl.policy.${name}.private_key=${conf.privateKey}'' else ''dbms.ssl.policy.${name}.private_key=${conf.baseDirectory}/${conf.privateKey}'' } ${if length (splitString "/" conf.privateKey) > 1 then ''dbms.ssl.policy.${name}.public_certificate=${conf.publicCertificate}'' else ''dbms.ssl.policy.${name}.public_certificate=${conf.baseDirectory}/${conf.publicCertificate}'' } dbms.ssl.policy.${name}.revoked_dir=${conf.revokedDir} dbms.ssl.policy.${name}.tls_versions=${concatStringsSep "," conf.tlsVersions} dbms.ssl.policy.${name}.trust_all=${boolToString conf.trustAll} dbms.ssl.policy.${name}.trusted_dir=${conf.trustedDir} '' ) cfg.ssl.policies; serverConfig = pkgs.writeText "neo4j.conf" '' # General dbms.allow_upgrade=${boolToString cfg.allowUpgrade} dbms.connectors.default_listen_address=${cfg.defaultListenAddress} dbms.read_only=${boolToString cfg.readOnly} ${optionalString (cfg.workerCount > 0) '' dbms.threads.worker_count=${toString cfg.workerCount} ''} # Directories dbms.directories.certificates=${cfg.directories.certificates} dbms.directories.data=${cfg.directories.data} dbms.directories.logs=${cfg.directories.home}/logs dbms.directories.plugins=${cfg.directories.plugins} ${optionalString (cfg.constrainLoadCsv) '' dbms.directories.import=${cfg.directories.imports} ''} # HTTP Connector ${optionalString (cfg.http.enable) '' dbms.connector.http.enabled=${boolToString cfg.http.enable} dbms.connector.http.listen_address=${cfg.http.listenAddress} ''} ${optionalString (!cfg.http.enable) '' # It is not possible to disable the HTTP connector. To fully prevent # clients from connecting to HTTP, block the HTTP port (7474 by default) # via firewall. listen_address is set to the loopback interface to # prevent remote clients from connecting. dbms.connector.http.listen_address=127.0.0.1 ''} # HTTPS Connector dbms.connector.https.enabled=${boolToString cfg.https.enable} dbms.connector.https.listen_address=${cfg.https.listenAddress} https.ssl_policy=${cfg.https.sslPolicy} # BOLT Connector dbms.connector.bolt.enabled=${boolToString cfg.bolt.enable} dbms.connector.bolt.listen_address=${cfg.bolt.listenAddress} bolt.ssl_policy=${cfg.bolt.sslPolicy} dbms.connector.bolt.tls_level=${cfg.bolt.tlsLevel} # neo4j-shell dbms.shell.enabled=${boolToString cfg.shell.enable} # SSL Policies ${concatStringsSep "\n" sslPolicies} # Default retention policy from neo4j.conf dbms.tx_log.rotation.retention_policy=1 days # Default JVM parameters from neo4j.conf dbms.jvm.additional=-XX:+UseG1GC dbms.jvm.additional=-XX:-OmitStackTraceInFastThrow dbms.jvm.additional=-XX:+AlwaysPreTouch dbms.jvm.additional=-XX:+UnlockExperimentalVMOptions dbms.jvm.additional=-XX:+TrustFinalNonStaticFields dbms.jvm.additional=-XX:+DisableExplicitGC dbms.jvm.additional=-Djdk.tls.ephemeralDHKeySize=2048 dbms.jvm.additional=-Djdk.tls.rejectClientInitiatedRenegotiation=true dbms.jvm.additional=-Dunsupported.dbms.udc.source=tarball # Usage Data Collector dbms.udc.enabled=${boolToString cfg.udc.enable} # Extra Configuration ${cfg.extraServerConfig} ''; in { ###### interface options.services.neo4j = { enable = mkOption { type = types.bool; default = false; description = '' Whether to enable Neo4j Community Edition. ''; }; allowUpgrade = mkOption { type = types.bool; default = false; description = '' Allow upgrade of Neo4j database files from an older version. ''; }; constrainLoadCsv = mkOption { type = types.bool; default = true; description = '' Sets the root directory for file URLs used with the Cypher LOAD CSV clause to be that defined by . It restricts access to only those files within that directory and its subdirectories. Setting this option to false introduces possible security problems. ''; }; defaultListenAddress = mkOption { type = types.str; default = "127.0.0.1"; description = '' Default network interface to listen for incoming connections. To listen for connections on all interfaces, use "0.0.0.0". Specifies the default IP address and address part of connector specific options. To bind specific connectors to a specific network interfaces, specify the entire option for that connector. ''; }; extraServerConfig = mkOption { type = types.lines; default = ""; description = '' Extra configuration for Neo4j Community server. Refer to the complete reference of Neo4j configuration settings. ''; }; package = mkOption { type = types.package; default = pkgs.neo4j; defaultText = "pkgs.neo4j"; description = '' Neo4j package to use. ''; }; readOnly = mkOption { type = types.bool; default = false; description = '' Only allow read operations from this Neo4j instance. ''; }; workerCount = mkOption { type = types.ints.between 0 44738; default = 0; description = '' Number of Neo4j worker threads, where the default of 0 indicates a worker count equal to the number of available processors. ''; }; bolt = { enable = mkOption { type = types.bool; default = true; description = '' Enable the BOLT connector for Neo4j. Setting this option to false will stop Neo4j from listening for incoming connections on the BOLT port (7687 by default). ''; }; listenAddress = mkOption { type = types.str; default = ":7687"; description = '' Neo4j listen address for BOLT traffic. The listen address is expressed in the format <ip-address>:<port-number>. ''; }; sslPolicy = mkOption { type = types.str; default = "legacy"; description = '' Neo4j SSL policy for BOLT traffic. The legacy policy is a special policy which is not defined in the policy configuration section, but rather derives from and associated files (by default: neo4j.key and neo4j.cert). Its use will be deprecated. Note: This connector must be configured to support/require SSL/TLS for the legacy policy to actually be utilized. See . ''; }; tlsLevel = mkOption { type = types.enum [ "REQUIRED" "OPTIONAL" "DISABLED" ]; default = "OPTIONAL"; description = '' SSL/TSL requirement level for BOLT traffic. ''; }; }; directories = { certificates = mkOption { type = types.path; default = "${cfg.directories.home}/certificates"; description = '' Directory for storing certificates to be used by Neo4j for TLS connections. When setting this directory to something other than its default, ensure the directory's existence, and that read/write permissions are given to the Neo4j daemon user neo4j. Note that changing this directory from its default will prevent the directory structure required for each SSL policy from being automatically generated. A policy's directory structure as defined by its , and must then be setup manually. The existence of these directories is mandatory, as well as the presence of the certificate file and the private key. Ensure the correct permissions are set on these directories and files. ''; }; data = mkOption { type = types.path; default = "${cfg.directories.home}/data"; description = '' Path of the data directory. You must not configure more than one Neo4j installation to use the same data directory. When setting this directory to something other than its default, ensure the directory's existence, and that read/write permissions are given to the Neo4j daemon user neo4j. ''; }; home = mkOption { type = types.path; default = "/var/lib/neo4j"; description = '' Path of the Neo4j home directory. Other default directories are subdirectories of this path. This directory will be created if non-existent, and its ownership will be chown to the Neo4j daemon user neo4j. ''; }; imports = mkOption { type = types.path; default = "${cfg.directories.home}/import"; description = '' The root directory for file URLs used with the Cypher LOAD CSV clause. Only meaningful when is set to true. When setting this directory to something other than its default, ensure the directory's existence, and that read permission is given to the Neo4j daemon user neo4j. ''; }; plugins = mkOption { type = types.path; default = "${cfg.directories.home}/plugins"; description = '' Path of the database plugin directory. Compiled Java JAR files that contain database procedures will be loaded if they are placed in this directory. When setting this directory to something other than its default, ensure the directory's existence, and that read permission is given to the Neo4j daemon user neo4j. ''; }; }; http = { enable = mkOption { type = types.bool; default = true; description = '' The HTTP connector is required for Neo4j, and cannot be disabled. Setting this option to false will force the HTTP connector's to the loopback interface to prevent connection of remote clients. To prevent all clients from connecting, block the HTTP port (7474 by default) by firewall. ''; }; listenAddress = mkOption { type = types.str; default = ":7474"; description = '' Neo4j listen address for HTTP traffic. The listen address is expressed in the format <ip-address>:<port-number>. ''; }; }; https = { enable = mkOption { type = types.bool; default = true; description = '' Enable the HTTPS connector for Neo4j. Setting this option to false will stop Neo4j from listening for incoming connections on the HTTPS port (7473 by default). ''; }; listenAddress = mkOption { type = types.str; default = ":7473"; description = '' Neo4j listen address for HTTPS traffic. The listen address is expressed in the format <ip-address>:<port-number>. ''; }; sslPolicy = mkOption { type = types.str; default = "legacy"; description = '' Neo4j SSL policy for HTTPS traffic. The legacy policy is a special policy which is not defined in the policy configuration section, but rather derives from and associated files (by default: neo4j.key and neo4j.cert). Its use will be deprecated. ''; }; }; shell = { enable = mkOption { type = types.bool; default = false; description = '' Enable a remote shell server which Neo4j Shell clients can log in to. Only applicable to neo4j-shell. ''; }; }; ssl.policies = mkOption { type = with types; attrsOf (submodule ({ name, config, options, ... }: { options = { allowKeyGeneration = mkOption { type = types.bool; default = false; description = '' Allows the generation of a private key and associated self-signed certificate. Only performed when both objects cannot be found for this policy. It is recommended to turn this off again after keys have been generated. The public certificate is required to be duplicated to the directory holding trusted certificates as defined by the option. Keys should in general be generated and distributed offline by a trusted certificate authority and not by utilizing this mode. ''; }; baseDirectory = mkOption { type = types.path; default = "${cfg.directories.certificates}/${name}"; description = '' The mandatory base directory for cryptographic objects of this policy. This path is only automatically generated when this option as well as are left at their default. Ensure read/write permissions are given to the Neo4j daemon user neo4j. It is also possible to override each individual configuration with absolute paths. See the and policy options. ''; }; ciphers = mkOption { type = types.nullOr (types.listOf types.str); default = null; description = '' Restrict the allowed ciphers of this policy to those defined here. The default ciphers are those of the JVM platform. ''; }; clientAuth = mkOption { type = types.enum [ "NONE" "OPTIONAL" "REQUIRE" ]; default = "REQUIRE"; description = '' The client authentication stance for this policy. ''; }; privateKey = mkOption { type = types.str; default = "private.key"; description = '' The name of private PKCS #8 key file for this policy to be found in the , or the absolute path to the key file. It is mandatory that a key can be found or generated. ''; }; publicCertificate = mkOption { type = types.str; default = "public.crt"; description = '' The name of public X.509 certificate (chain) file in PEM format for this policy to be found in the , or the absolute path to the certificate file. It is mandatory that a certificate can be found or generated. The public certificate is required to be duplicated to the directory holding trusted certificates as defined by the option. ''; }; revokedDir = mkOption { type = types.path; default = "${config.baseDirectory}/revoked"; description = '' Path to directory of CRLs (Certificate Revocation Lists) in PEM format. Must be an absolute path. The existence of this directory is mandatory and will need to be created manually when: setting this option to something other than its default; setting either this policy's or to something other than their default. Ensure read/write permissions are given to the Neo4j daemon user neo4j. ''; }; tlsVersions = mkOption { type = types.listOf types.str; default = [ "TLSv1.2" ]; description = '' Restrict the TLS protocol versions of this policy to those defined here. ''; }; trustAll = mkOption { type = types.bool; default = false; description = '' Makes this policy trust all remote parties. Enabling this is not recommended and the policy's trusted directory will be ignored. Use of this mode is discouraged. It would offer encryption but no security. ''; }; trustedDir = mkOption { type = types.path; default = "${config.baseDirectory}/trusted"; description = '' Path to directory of X.509 certificates in PEM format for trusted parties. Must be an absolute path. The existence of this directory is mandatory and will need to be created manually when: setting this option to something other than its default; setting either this policy's or to something other than their default. Ensure read/write permissions are given to the Neo4j daemon user neo4j. The public certificate as defined by is required to be duplicated to this directory. ''; }; directoriesToCreate = mkOption { type = types.listOf types.path; internal = true; readOnly = true; description = '' Directories of this policy that will be created automatically when the certificates directory is left at its default value. This includes all options of type path that are left at their default value. ''; }; }; config.directoriesToCreate = optionals (certDirOpt.highestPrio >= 1500 && options.baseDirectory.highestPrio >= 1500) (map (opt: opt.value) (filter isDefaultPathOption (attrValues options))); })); default = {}; description = '' Defines the SSL policies for use with Neo4j connectors. Each attribute of this set defines a policy, with the attribute name defining the name of the policy and its namespace. Refer to the operations manual section on Neo4j's SSL Framework for further details. ''; }; udc = { enable = mkOption { type = types.bool; default = false; description = '' Enable the Usage Data Collector which Neo4j uses to collect usage data. Refer to the operations manual section on the Usage Data Collector for more information. ''; }; }; }; ###### implementation config = let # Assertion helpers policyNameList = attrNames cfg.ssl.policies; validPolicyNameList = [ "legacy" ] ++ policyNameList; validPolicyNameString = concatStringsSep ", " validPolicyNameList; # Capture various directories left at their default so they can be created. defaultDirectoriesToCreate = map (opt: opt.value) (filter isDefaultPathOption (attrValues options.services.neo4j.directories)); policyDirectoriesToCreate = concatMap (pol: pol.directoriesToCreate) (attrValues cfg.ssl.policies); in mkIf cfg.enable { assertions = [ { assertion = !elem "legacy" policyNameList; message = "The policy 'legacy' is special to Neo4j, and its name is reserved."; } { assertion = elem cfg.bolt.sslPolicy validPolicyNameList; message = "Invalid policy assigned: `services.neo4j.bolt.sslPolicy = \"${cfg.bolt.sslPolicy}\"`, defined policies are: ${validPolicyNameString}"; } { assertion = elem cfg.https.sslPolicy validPolicyNameList; message = "Invalid policy assigned: `services.neo4j.https.sslPolicy = \"${cfg.https.sslPolicy}\"`, defined policies are: ${validPolicyNameString}"; } ]; systemd.services.neo4j = { description = "Neo4j Daemon"; wantedBy = [ "multi-user.target" ]; after = [ "network.target" ]; environment = { NEO4J_HOME = "${cfg.package}/share/neo4j"; NEO4J_CONF = "${cfg.directories.home}/conf"; }; serviceConfig = { ExecStart = "${cfg.package}/bin/neo4j console"; User = "neo4j"; PermissionsStartOnly = true; LimitNOFILE = 40000; }; preStart = '' # Directories Setup # Always ensure home exists with nested conf, logs directories. mkdir -m 0700 -p ${cfg.directories.home}/{conf,logs} # Create other sub-directories and policy directories that have been left at their default. ${concatMapStringsSep "\n" ( dir: '' mkdir -m 0700 -p ${dir} '') (defaultDirectoriesToCreate ++ policyDirectoriesToCreate)} # Place the configuration where Neo4j can find it. ln -fs ${serverConfig} ${cfg.directories.home}/conf/neo4j.conf # Ensure neo4j user ownership chown -R neo4j ${cfg.directories.home} ''; }; environment.systemPackages = [ cfg.package ]; users.users = singleton { name = "neo4j"; uid = config.ids.uids.neo4j; description = "Neo4j daemon user"; home = cfg.directories.home; }; }; meta = { maintainers = with lib.maintainers; [ patternspandemic ]; }; }