config.c

/* Copyright (c) 2001 Matej Pfajfar.
 * Copyright (c) 2001-2004, Roger Dingledine.
 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
 * Copyright (c) 2007-2018, The Tor Project, Inc. */
/* See LICENSE for licensing information */

/**
 * \file config.c
 * \brief Code to interpret the user's configuration of Tor.
 *
 * This module handles torrc configuration file, including parsing it,
 * combining it with torrc.defaults and the command line, allowing
 * user changes to it (via editing and SIGHUP or via the control port),
 * writing it back to disk (because of SAVECONF from the control port),
 * and -- most importantly, acting on it.
 *
 * The module additionally has some tools for manipulating and
 * inspecting values that are calculated as a result of the
 * configured options.
 *
 * <h3>How to add new options</h3>
 *
 * To add new items to the torrc, there are a minimum of three places to edit:
 * <ul>
 *   <li>The or_options_t structure in or.h, where the options are stored.
 *   <li>The option_vars_ array below in this module, which configures
 *       the names of the torrc options, their types, their multiplicities,
 *       and their mappings to fields in or_options_t.
 *   <li>The manual in doc/tor.1.txt, to document what the new option
 *       is, and how it works.
 * </ul>
 *
 * Additionally, you might need to edit these places too:
 * <ul>
 *   <li>options_validate() below, in case you want to reject some possible
 *       values of the new configuration option.
 *   <li>options_transition_allowed() below, in case you need to
 *       forbid some or all changes in the option while Tor is
 *       running.
 *   <li>options_transition_affects_workers(), in case changes in the option
 *       might require Tor to relaunch or reconfigure its worker threads.
 *   <li>options_transition_affects_descriptor(), in case changes in the
 *       option might require a Tor relay to build and publish a new server
 *       descriptor.
 *   <li>options_act() and/or options_act_reversible(), in case there's some
 *       action that needs to be taken immediately based on the option's
 *       value.
 * </ul>
 *
 * <h3>Changing the value of an option</h3>
 *
 * Because of the SAVECONF command from the control port, it's a bad
 * idea to change the value of any user-configured option in the
 * or_options_t.  If you want to sometimes do this anyway, we recommend
 * that you create a secondary field in or_options_t; that you have the
 * user option linked only to the secondary field; that you use the
 * secondary field to initialize the one that Tor actually looks at; and that
 * you use the one Tor looks as the one that you modify.
 **/

#define CONFIG_PRIVATE
#include "core/or/or.h"
#include "feature/client/bridges.h"
#include "feature/client/addressmap.h"
#include "core/or/channel.h"
#include "core/or/circuitbuild.h"
#include "core/or/circuitlist.h"
#include "core/or/circuitmux.h"
#include "core/or/circuitmux_ewma.h"
#include "core/or/circuitstats.h"
#include "lib/compress/compress.h"
#include "app/config/config.h"
#include "lib/encoding/confline.h"
#include "core/mainloop/connection.h"
#include "core/or/connection_edge.h"
#include "core/or/connection_or.h"
#include "feature/dircache/consdiffmgr.h"
#include "feature/control/control.h"
#include "app/config/confparse.h"
#include "core/mainloop/cpuworker.h"
#include "lib/crypt_ops/crypto_rand.h"
#include "lib/crypt_ops/crypto_util.h"
#include "lib/crypt_ops/crypto_init.h"
#ifdef ENABLE_NSS
#include "lib/crypt_ops/crypto_nss_mgt.h"
#else
#include "lib/crypt_ops/crypto_openssl_mgt.h"
#endif
#include "feature/dircache/dirserv.h"
#include "feature/relay/dns.h"
#include "core/or/dos.h"
#include "feature/client/entrynodes.h"
#include "lib/log/git_revision.h"
#include "feature/stats/geoip.h"
#include "feature/hibernate/hibernate.h"
#include "core/mainloop/main.h"
#include "feature/nodelist/networkstatus.h"
#include "feature/nodelist/nodelist.h"
#include "core/or/policies.h"
#include "core/or/relay.h"
#include "feature/rend/rendclient.h"
#include "feature/rend/rendservice.h"
#include "feature/hs/hs_config.h"
#include "feature/stats/rephist.h"
#include "feature/relay/router.h"
#include "lib/sandbox/sandbox.h"
#include "feature/nodelist/routerlist.h"
#include "feature/nodelist/routerset.h"
#include "core/or/scheduler.h"
#include "app/config/statefile.h"
#include "feature/client/transports.h"
#include "feature/relay/ext_orport.h"
#include "feature/dircommon/voting_schedule.h"
#include "lib/net/resolve.h"
#ifdef _WIN32
#include <shlobj.h>
#endif
#ifdef HAVE_FCNTL_H
#include <fcntl.h>
#endif
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "lib/meminfo/meminfo.h"
#include "lib/osinfo/uname.h"
#include "lib/process/daemon.h"
#include "lib/process/pidfile.h"
#include "lib/process/restrict.h"
#include "lib/process/setuid.h"
#include "lib/process/subprocess.h"
#include "lib/net/gethostname.h"
#include "lib/thread/numcpus.h"

#include "lib/encoding/keyval.h"
#include "lib/fs/conffile.h"
#include "lib/evloop/procmon.h"

#include "feature/dirauth/dirvote.h"
#include "feature/dirauth/mode.h"

#include "core/or/connection_st.h"
#include "core/or/port_cfg_st.h"

#ifdef HAVE_SYSTEMD
#   if defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__)
/* Systemd's use of gcc's __INCLUDE_LEVEL__ extension macro appears to confuse
 * Coverity. Here's a kludge to unconfuse it.
 */
#   define __INCLUDE_LEVEL__ 2
#endif /* defined(__COVERITY__) && !defined(__INCLUDE_LEVEL__) */
#include <systemd/sd-daemon.h>
#endif /* defined(HAVE_SYSTEMD) */

/* Prefix used to indicate a Unix socket in a FooPort configuration. */
static const char unix_socket_prefix[] = "unix:";
/* Prefix used to indicate a Unix socket with spaces in it, in a FooPort
 * configuration. */
static const char unix_q_socket_prefix[] = "unix:\"";

/* limits for TCP send and recv buffer size used for constrained sockets */
#define MIN_CONSTRAINED_TCP_BUFFER 2048
#define MAX_CONSTRAINED_TCP_BUFFER 262144  /* 256k */

/** macro to help with the bulk rename of *DownloadSchedule to
 * *DowloadInitialDelay . */
#define DOWNLOAD_SCHEDULE(name) \
  { #name "DownloadSchedule", #name "DownloadInitialDelay", 0, 1 }

/** A list of abbreviations and aliases to map command-line options, obsolete
 * option names, or alternative option names, to their current values. */
static config_abbrev_t option_abbrevs_[] = {
  PLURAL(AuthDirBadDirCC),
  PLURAL(AuthDirBadExitCC),
  PLURAL(AuthDirInvalidCC),
  PLURAL(AuthDirRejectCC),
  PLURAL(EntryNode),
  PLURAL(ExcludeNode),
  PLURAL(FirewallPort),
  PLURAL(LongLivedPort),
  PLURAL(HiddenServiceNode),
  PLURAL(HiddenServiceExcludeNode),
  PLURAL(NumCPU),
  PLURAL(RendNode),
  PLURAL(RecommendedPackage),
  PLURAL(RendExcludeNode),
  PLURAL(StrictEntryNode),
  PLURAL(StrictExitNode),
  PLURAL(StrictNode),
  { "l", "Log", 1, 0},
  { "AllowUnverifiedNodes", "AllowInvalidNodes", 0, 0},
  { "AutomapHostSuffixes", "AutomapHostsSuffixes", 0, 0},
  { "AutomapHostOnResolve", "AutomapHostsOnResolve", 0, 0},
  { "BandwidthRateBytes", "BandwidthRate", 0, 0},
  { "BandwidthBurstBytes", "BandwidthBurst", 0, 0},
  { "DirFetchPostPeriod", "StatusFetchPeriod", 0, 0},
  { "DirServer", "DirAuthority", 0, 0}, /* XXXX later, make this warn? */
  { "MaxConn", "ConnLimit", 0, 1},
  { "MaxMemInCellQueues", "MaxMemInQueues", 0, 0},
  { "ORBindAddress", "ORListenAddress", 0, 0},
  { "DirBindAddress", "DirListenAddress", 0, 0},
  { "SocksBindAddress", "SocksListenAddress", 0, 0},
  { "UseHelperNodes", "UseEntryGuards", 0, 0},
  { "NumHelperNodes", "NumEntryGuards", 0, 0},
  { "UseEntryNodes", "UseEntryGuards", 0, 0},
  { "NumEntryNodes", "NumEntryGuards", 0, 0},
  { "ResolvConf", "ServerDNSResolvConfFile", 0, 1},
  { "SearchDomains", "ServerDNSSearchDomains", 0, 1},
  { "ServerDNSAllowBrokenResolvConf", "ServerDNSAllowBrokenConfig", 0, 0},
  { "PreferTunnelledDirConns", "PreferTunneledDirConns", 0, 0},
  { "BridgeAuthoritativeDirectory", "BridgeAuthoritativeDir", 0, 0},
  { "HashedControlPassword", "__HashedControlSessionPassword", 1, 0},
  { "VirtualAddrNetwork", "VirtualAddrNetworkIPv4", 0, 0},
  { "SocksSocketsGroupWritable", "UnixSocksGroupWritable", 0, 1},
  { "_HSLayer2Nodes", "HSLayer2Nodes", 0, 1 },
  { "_HSLayer3Nodes", "HSLayer3Nodes", 0, 1 },

  DOWNLOAD_SCHEDULE(ClientBootstrapConsensusAuthority),
  DOWNLOAD_SCHEDULE(ClientBootstrapConsensusAuthorityOnly),
  DOWNLOAD_SCHEDULE(ClientBootstrapConsensusFallback),
  DOWNLOAD_SCHEDULE(TestingBridge),
  DOWNLOAD_SCHEDULE(TestingBridgeBootstrap),
  DOWNLOAD_SCHEDULE(TestingClient),
  DOWNLOAD_SCHEDULE(TestingClientConsensus),
  DOWNLOAD_SCHEDULE(TestingServer),
  DOWNLOAD_SCHEDULE(TestingServerConsensus),

  { NULL, NULL, 0, 0},
};

/** dummy instance of or_options_t, used for type-checking its
 * members with CONF_CHECK_VAR_TYPE. */
DUMMY_TYPECHECK_INSTANCE(or_options_t);

/** An entry for config_vars: "The option <b>name</b> has type
 * CONFIG_TYPE_<b>conftype</b>, and corresponds to
 * or_options_t.<b>member</b>"
 */
#define VAR(name,conftype,member,initvalue)                             \
  { name, CONFIG_TYPE_ ## conftype, offsetof(or_options_t, member),     \
      initvalue CONF_TEST_MEMBERS(or_options_t, conftype, member) }
/** As VAR, but the option name and member name are the same. */
#define V(member,conftype,initvalue)                                    \
  VAR(#member, conftype, member, initvalue)
/** An entry for config_vars: "The option <b>name</b> is obsolete." */
#ifdef TOR_UNIT_TESTS
#define OBSOLETE(name) { name, CONFIG_TYPE_OBSOLETE, 0, NULL, {.INT=NULL} }
#else
#define OBSOLETE(name) { name, CONFIG_TYPE_OBSOLETE, 0, NULL }
#endif

/**
 * Macro to declare *Port options.  Each one comes in three entries.
 * For example, most users should use "SocksPort" to configure the
 * socks port, but TorBrowser wants to use __SocksPort so that it
 * isn't stored by SAVECONF.  The SocksPortLines virtual option is
 * used to query both options from the controller.
 */
#define VPORT(member)                                           \
  VAR(#member "Lines", LINELIST_V, member ## _lines, NULL),     \
  VAR(#member, LINELIST_S, member ## _lines, NULL),             \
  VAR("__" #member, LINELIST_S, member ## _lines, NULL)

/** UINT64_MAX as a decimal string */
#define UINT64_MAX_STRING "18446744073709551615"

/** Array of configuration options.  Until we disallow nonstandard
 * abbreviations, order is significant, since the first matching option will
 * be chosen first.
 */
static config_var_t option_vars_[] = {
  V(AccountingMax,               MEMUNIT,  "0 bytes"),
  VAR("AccountingRule",          STRING,   AccountingRule_option,  "max"),
  V(AccountingStart,             STRING,   NULL),
  V(Address,                     STRING,   NULL),
  OBSOLETE("AllowDotExit"),
  OBSOLETE("AllowInvalidNodes"),
  V(AllowNonRFC953Hostnames,     BOOL,     "0"),
  OBSOLETE("AllowSingleHopCircuits"),
  OBSOLETE("AllowSingleHopExits"),
  V(AlternateBridgeAuthority,    LINELIST, NULL),
  V(AlternateDirAuthority,       LINELIST, NULL),
  OBSOLETE("AlternateHSAuthority"),
  V(AssumeReachable,             BOOL,     "0"),
  OBSOLETE("AuthDirBadDir"),
  OBSOLETE("AuthDirBadDirCCs"),
  V(AuthDirBadExit,              LINELIST, NULL),
  V(AuthDirBadExitCCs,           CSV,      ""),
  V(AuthDirInvalid,              LINELIST, NULL),
  V(AuthDirInvalidCCs,           CSV,      ""),
  V(AuthDirFastGuarantee,        MEMUNIT,  "100 KB"),
  V(AuthDirGuardBWGuarantee,     MEMUNIT,  "2 MB"),
  V(AuthDirPinKeys,              BOOL,     "1"),
  V(AuthDirReject,               LINELIST, NULL),
  V(AuthDirRejectCCs,            CSV,      ""),
  OBSOLETE("AuthDirRejectUnlisted"),
  OBSOLETE("AuthDirListBadDirs"),
  V(AuthDirListBadExits,         BOOL,     "0"),
  V(AuthDirMaxServersPerAddr,    UINT,     "2"),
  OBSOLETE("AuthDirMaxServersPerAuthAddr"),
  V(AuthDirHasIPv6Connectivity,  BOOL,     "0"),
  VAR("AuthoritativeDirectory",  BOOL, AuthoritativeDir,    "0"),
  V(AutomapHostsOnResolve,       BOOL,     "0"),
  V(AutomapHostsSuffixes,        CSV,      ".onion,.exit"),
  V(AvoidDiskWrites,             BOOL,     "0"),
  V(BandwidthBurst,              MEMUNIT,  "1 GB"),
  V(BandwidthRate,               MEMUNIT,  "1 GB"),
  V(BridgeAuthoritativeDir,      BOOL,     "0"),
  VAR("Bridge",                  LINELIST, Bridges,    NULL),
  V(BridgePassword,              STRING,   NULL),
  V(BridgeRecordUsageByCountry,  BOOL,     "1"),
  V(BridgeRelay,                 BOOL,     "0"),
  V(BridgeDistribution,          STRING,   NULL),
  VAR("CacheDirectory",          FILENAME, CacheDirectory_option, NULL),
  V(CacheDirectoryGroupReadable, BOOL,     "0"),
  V(CellStatistics,              BOOL,     "0"),
  V(PaddingStatistics,           BOOL,     "1"),
  V(LearnCircuitBuildTimeout,    BOOL,     "1"),
  V(CircuitBuildTimeout,         INTERVAL, "0"),
  OBSOLETE("CircuitIdleTimeout"),
  V(CircuitsAvailableTimeout,    INTERVAL, "0"),
  V(CircuitStreamTimeout,        INTERVAL, "0"),
  V(CircuitPriorityHalflife,     DOUBLE,  "-1.0"), /*negative:'Use default'*/
  V(ClientDNSRejectInternalAddresses, BOOL,"1"),
  V(ClientOnly,                  BOOL,     "0"),
  V(ClientPreferIPv6ORPort,      AUTOBOOL, "auto"),
  V(ClientPreferIPv6DirPort,     AUTOBOOL, "auto"),
  V(ClientRejectInternalAddresses, BOOL,   "1"),
  V(ClientTransportPlugin,       LINELIST, NULL),
  V(ClientUseIPv6,               BOOL,     "0"),
  V(ClientUseIPv4,               BOOL,     "1"),
  V(ConsensusParams,             STRING,   NULL),
  V(ConnLimit,                   UINT,     "1000"),
  V(ConnDirectionStatistics,     BOOL,     "0"),
  V(ConstrainedSockets,          BOOL,     "0"),
  V(ConstrainedSockSize,         MEMUNIT,  "8192"),
  V(ContactInfo,                 STRING,   NULL),
  OBSOLETE("ControlListenAddress"),
  VPORT(ControlPort),
  V(ControlPortFileGroupReadable,BOOL,     "0"),
  V(ControlPortWriteToFile,      FILENAME, NULL),
  V(ControlSocket,               LINELIST, NULL),
  V(ControlSocketsGroupWritable, BOOL,     "0"),
  V(UnixSocksGroupWritable,    BOOL,     "0"),
  V(CookieAuthentication,        BOOL,     "0"),
  V(CookieAuthFileGroupReadable, BOOL,     "0"),
  V(CookieAuthFile,              STRING,   NULL),
  V(CountPrivateBandwidth,       BOOL,     "0"),
  VAR("DataDirectory",           FILENAME, DataDirectory_option, NULL),
  V(DataDirectoryGroupReadable,  BOOL,     "0"),
  V(DisableOOSCheck,             BOOL,     "1"),
  V(DisableNetwork,              BOOL,     "0"),
  V(DirAllowPrivateAddresses,    BOOL,     "0"),
  V(TestingAuthDirTimeToLearnReachability, INTERVAL, "30 minutes"),
  OBSOLETE("DirListenAddress"),
  V(DirPolicy,                   LINELIST, NULL),
  VPORT(DirPort),
  V(DirPortFrontPage,            FILENAME, NULL),
  VAR("DirReqStatistics",        BOOL,     DirReqStatistics_option, "1"),
  VAR("DirAuthority",            LINELIST, DirAuthorities, NULL),
  V(DirCache,                    BOOL,     "1"),
  /* A DirAuthorityFallbackRate of 0.1 means that 0.5% of clients try an
   * authority when all fallbacks are up, and 2% try an authority when 25% of
   * fallbacks are down. (We rebuild the list when 25% of fallbacks are down).
   *
   * We want to reduce load on authorities, but keep these two figures within
   * an order of magnitude, so there isn't too much load shifting to
   * authorities when fallbacks go down. */
  V(DirAuthorityFallbackRate,    DOUBLE,   "0.1"),
  V(DisableAllSwap,              BOOL,     "0"),
  V(DisableDebuggerAttachment,   BOOL,     "1"),
  OBSOLETE("DisableIOCP"),
  OBSOLETE("DisableV2DirectoryInfo_"),
  OBSOLETE("DynamicDHGroups"),
  VPORT(DNSPort),
  OBSOLETE("DNSListenAddress"),
  /* DoS circuit creation options. */
  V(DoSCircuitCreationEnabled,   AUTOBOOL, "auto"),
  V(DoSCircuitCreationMinConnections,      UINT, "0"),
  V(DoSCircuitCreationRate,      UINT,     "0"),
  V(DoSCircuitCreationBurst,     UINT,     "0"),
  V(DoSCircuitCreationDefenseType,         INT,  "0"),
  V(DoSCircuitCreationDefenseTimePeriod,   INTERVAL, "0"),
  /* DoS connection options. */
  V(DoSConnectionEnabled,        AUTOBOOL, "auto"),
  V(DoSConnectionMaxConcurrentCount,       UINT, "0"),
  V(DoSConnectionDefenseType,    INT,      "0"),
  /* DoS single hop client options. */
  V(DoSRefuseSingleHopClientRendezvous,    AUTOBOOL, "auto"),
  V(DownloadExtraInfo,           BOOL,     "0"),
  V(TestingEnableConnBwEvent,    BOOL,     "0"),
  V(TestingEnableCellStatsEvent, BOOL,     "0"),
  OBSOLETE("TestingEnableTbEmptyEvent"),
  V(EnforceDistinctSubnets,      BOOL,     "1"),
  V(EntryNodes,                  ROUTERSET,   NULL),
  V(EntryStatistics,             BOOL,     "0"),
  V(TestingEstimatedDescriptorPropagationTime, INTERVAL, "10 minutes"),
  V(ExcludeNodes,                ROUTERSET, NULL),
  V(ExcludeExitNodes,            ROUTERSET, NULL),
  OBSOLETE("ExcludeSingleHopRelays"),
  V(ExitNodes,                   ROUTERSET, NULL),
  V(ExitPolicy,                  LINELIST, NULL),
  V(ExitPolicyRejectPrivate,     BOOL,     "1"),
  V(ExitPolicyRejectLocalInterfaces, BOOL, "0"),
  V(ExitPortStatistics,          BOOL,     "0"),
  V(ExtendAllowPrivateAddresses, BOOL,     "0"),
  V(ExitRelay,                   AUTOBOOL, "auto"),
  VPORT(ExtORPort),
  V(ExtORPortCookieAuthFile,     STRING,   NULL),
  V(ExtORPortCookieAuthFileGroupReadable, BOOL, "0"),
  V(ExtraInfoStatistics,         BOOL,     "1"),
  V(ExtendByEd25519ID,           AUTOBOOL, "auto"),
  V(FallbackDir,                 LINELIST, NULL),

  V(UseDefaultFallbackDirs,      BOOL,     "1"),

  OBSOLETE("FallbackNetworkstatusFile"),
  V(FascistFirewall,             BOOL,     "0"),
  V(FirewallPorts,               CSV,      ""),
  OBSOLETE("FastFirstHopPK"),
  V(FetchDirInfoEarly,           BOOL,     "0"),
  V(FetchDirInfoExtraEarly,      BOOL,     "0"),
  V(FetchServerDescriptors,      BOOL,     "1"),
  V(FetchHidServDescriptors,     BOOL,     "1"),
  V(FetchUselessDescriptors,     BOOL,     "0"),
  OBSOLETE("FetchV2Networkstatus"),
  V(GeoIPExcludeUnknown,         AUTOBOOL, "auto"),
#ifdef _WIN32
  V(GeoIPFile,                   FILENAME, "<default>"),
  V(GeoIPv6File,                 FILENAME, "<default>"),
#else
  V(GeoIPFile,                   FILENAME,
    SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "geoip"),
  V(GeoIPv6File,                 FILENAME,
    SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "geoip6"),
#endif /* defined(_WIN32) */
  OBSOLETE("Group"),
  V(GuardLifetime,               INTERVAL, "0 minutes"),
  V(HardwareAccel,               BOOL,     "0"),
  V(HeartbeatPeriod,             INTERVAL, "6 hours"),
  V(MainloopStats,               BOOL,     "0"),
  V(AccelName,                   STRING,   NULL),
  V(AccelDir,                    FILENAME, NULL),
  V(HashedControlPassword,       LINELIST, NULL),
  OBSOLETE("HidServDirectoryV2"),
  VAR("HiddenServiceDir",    LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceDirGroupReadable",  LINELIST_S, RendConfigLines, NULL),
  VAR("HiddenServiceOptions",LINELIST_V, RendConfigLines,    NULL),
  VAR("HiddenServicePort",   LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceVersion",LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceAuthorizeClient",LINELIST_S,RendConfigLines, NULL),
  VAR("HiddenServiceAllowUnknownPorts",LINELIST_S, RendConfigLines, NULL),
  VAR("HiddenServiceMaxStreams",LINELIST_S, RendConfigLines, NULL),
  VAR("HiddenServiceMaxStreamsCloseCircuit",LINELIST_S, RendConfigLines, NULL),
  VAR("HiddenServiceNumIntroductionPoints", LINELIST_S, RendConfigLines, NULL),
  VAR("HiddenServiceStatistics", BOOL, HiddenServiceStatistics_option, "1"),
  V(HidServAuth,                 LINELIST, NULL),
  V(ClientOnionAuthDir,          FILENAME, NULL),
  OBSOLETE("CloseHSClientCircuitsImmediatelyOnTimeout"),
  OBSOLETE("CloseHSServiceRendCircuitsImmediatelyOnTimeout"),
  V(HiddenServiceSingleHopMode,  BOOL,     "0"),
  V(HiddenServiceNonAnonymousMode,BOOL,    "0"),
  V(HTTPProxy,                   STRING,   NULL),
  V(HTTPProxyAuthenticator,      STRING,   NULL),
  V(HTTPSProxy,                  STRING,   NULL),
  V(HTTPSProxyAuthenticator,     STRING,   NULL),
  VPORT(HTTPTunnelPort),
  V(IPv6Exit,                    BOOL,     "0"),
  VAR("ServerTransportPlugin",   LINELIST, ServerTransportPlugin,  NULL),
  V(ServerTransportListenAddr,   LINELIST, NULL),
  V(ServerTransportOptions,      LINELIST, NULL),
  V(SigningKeyLifetime,          INTERVAL, "30 days"),
  V(Socks4Proxy,                 STRING,   NULL),
  V(Socks5Proxy,                 STRING,   NULL),
  V(Socks5ProxyUsername,         STRING,   NULL),
  V(Socks5ProxyPassword,         STRING,   NULL),
  VAR("KeyDirectory",            FILENAME, KeyDirectory_option, NULL),
  V(KeyDirectoryGroupReadable,   BOOL,     "0"),
  VAR("HSLayer2Nodes",           ROUTERSET,  HSLayer2Nodes,  NULL),
  VAR("HSLayer3Nodes",           ROUTERSET,  HSLayer3Nodes,  NULL),
  V(KeepalivePeriod,             INTERVAL, "5 minutes"),
  V(KeepBindCapabilities,            AUTOBOOL, "auto"),
  VAR("Log",                     LINELIST, Logs,             NULL),
  V(LogMessageDomains,           BOOL,     "0"),
  V(LogTimeGranularity,          MSEC_INTERVAL, "1 second"),
  V(TruncateLogFile,             BOOL,     "0"),
  V(SyslogIdentityTag,           STRING,   NULL),
  V(AndroidIdentityTag,          STRING,   NULL),
  V(LongLivedPorts,              CSV,
        "21,22,706,1863,5050,5190,5222,5223,6523,6667,6697,8300"),
  VAR("MapAddress",              LINELIST, AddressMap,           NULL),
  V(MaxAdvertisedBandwidth,      MEMUNIT,  "1 GB"),
  V(MaxCircuitDirtiness,         INTERVAL, "10 minutes"),
  V(MaxClientCircuitsPending,    UINT,     "32"),
  V(MaxConsensusAgeForDiffs,     INTERVAL, "0 seconds"),
  VAR("MaxMemInQueues",          MEMUNIT,   MaxMemInQueues_raw, "0"),
  OBSOLETE("MaxOnionsPending"),
  V(MaxOnionQueueDelay,          MSEC_INTERVAL, "1750 msec"),
  V(MaxUnparseableDescSizeToLog, MEMUNIT, "10 MB"),
  V(MinMeasuredBWsForAuthToIgnoreAdvertised, INT, "500"),
  VAR("MyFamily",                LINELIST, MyFamily_lines,       NULL),
  V(NewCircuitPeriod,            INTERVAL, "30 seconds"),
  OBSOLETE("NamingAuthoritativeDirectory"),
  OBSOLETE("NATDListenAddress"),
  VPORT(NATDPort),
  V(Nickname,                    STRING,   NULL),
  OBSOLETE("PredictedPortsRelevanceTime"),
  OBSOLETE("WarnUnsafeSocks"),
  VAR("NodeFamily",              LINELIST, NodeFamilies,         NULL),
  V(NoExec,                      BOOL,     "0"),
  V(NumCPUs,                     UINT,     "0"),
  V(NumDirectoryGuards,          UINT,     "0"),
  V(NumEntryGuards,              UINT,     "0"),
  V(NumPrimaryGuards,            UINT,     "0"),
  V(OfflineMasterKey,            BOOL,     "0"),
  OBSOLETE("ORListenAddress"),
  VPORT(ORPort),
  V(OutboundBindAddress,         LINELIST,   NULL),
  V(OutboundBindAddressOR,       LINELIST,   NULL),
  V(OutboundBindAddressExit,     LINELIST,   NULL),

  OBSOLETE("PathBiasDisableRate"),
  V(PathBiasCircThreshold,       INT,      "-1"),
  V(PathBiasNoticeRate,          DOUBLE,   "-1"),
  V(PathBiasWarnRate,            DOUBLE,   "-1"),
  V(PathBiasExtremeRate,         DOUBLE,   "-1"),
  V(PathBiasScaleThreshold,      INT,      "-1"),
  OBSOLETE("PathBiasScaleFactor"),
  OBSOLETE("PathBiasMultFactor"),
  V(PathBiasDropGuards,          AUTOBOOL, "0"),
  OBSOLETE("PathBiasUseCloseCounts"),

  V(PathBiasUseThreshold,       INT,      "-1"),
  V(PathBiasNoticeUseRate,          DOUBLE,   "-1"),
  V(PathBiasExtremeUseRate,         DOUBLE,   "-1"),
  V(PathBiasScaleUseThreshold,      INT,      "-1"),

  V(PathsNeededToBuildCircuits,  DOUBLE,   "-1"),
  V(PerConnBWBurst,              MEMUNIT,  "0"),
  V(PerConnBWRate,               MEMUNIT,  "0"),
  V(PidFile,                     STRING,   NULL),
  V(TestingTorNetwork,           BOOL,     "0"),
  V(TestingMinExitFlagThreshold, MEMUNIT,  "0"),
  V(TestingMinFastFlagThreshold, MEMUNIT,  "0"),

  V(TestingLinkCertLifetime,          INTERVAL, "2 days"),
  V(TestingAuthKeyLifetime,          INTERVAL, "2 days"),
  V(TestingLinkKeySlop,              INTERVAL, "3 hours"),
  V(TestingAuthKeySlop,              INTERVAL, "3 hours"),
  V(TestingSigningKeySlop,           INTERVAL, "1 day"),

  V(OptimisticData,              AUTOBOOL, "auto"),
  OBSOLETE("PortForwarding"),
  OBSOLETE("PortForwardingHelper"),
  OBSOLETE("PreferTunneledDirConns"),
  V(ProtocolWarnings,            BOOL,     "0"),
  V(PublishServerDescriptor,     CSV,      "1"),
  V(PublishHidServDescriptors,   BOOL,     "1"),
  V(ReachableAddresses,          LINELIST, NULL),
  V(ReachableDirAddresses,       LINELIST, NULL),
  V(ReachableORAddresses,        LINELIST, NULL),
  V(RecommendedVersions,         LINELIST, NULL),
  V(RecommendedClientVersions,   LINELIST, NULL),
  V(RecommendedServerVersions,   LINELIST, NULL),
  V(RecommendedPackages,         LINELIST, NULL),
  V(ReducedConnectionPadding,    BOOL,     "0"),
  V(ConnectionPadding,           AUTOBOOL, "auto"),
  V(RefuseUnknownExits,          AUTOBOOL, "auto"),
  V(RejectPlaintextPorts,        CSV,      ""),
  V(RelayBandwidthBurst,         MEMUNIT,  "0"),
  V(RelayBandwidthRate,          MEMUNIT,  "0"),
  V(RendPostPeriod,              INTERVAL, "1 hour"),
  V(RephistTrackTime,            INTERVAL, "24 hours"),
  V(RunAsDaemon,                 BOOL,     "0"),
  V(ReducedExitPolicy,           BOOL,     "0"),
  OBSOLETE("RunTesting"), // currently unused
  V(Sandbox,                     BOOL,     "0"),
  V(SafeLogging,                 STRING,   "1"),
  V(SafeSocks,                   BOOL,     "0"),
  V(ServerDNSAllowBrokenConfig,  BOOL,     "1"),
  V(ServerDNSAllowNonRFC953Hostnames, BOOL,"0"),
  V(ServerDNSDetectHijacking,    BOOL,     "1"),
  V(ServerDNSRandomizeCase,      BOOL,     "1"),
  V(ServerDNSResolvConfFile,     STRING,   NULL),
  V(ServerDNSSearchDomains,      BOOL,     "0"),
  V(ServerDNSTestAddresses,      CSV,
      "www.google.com,www.mit.edu,www.yahoo.com,www.slashdot.org"),
  OBSOLETE("SchedulerLowWaterMark__"),
  OBSOLETE("SchedulerHighWaterMark__"),
  OBSOLETE("SchedulerMaxFlushCells__"),
  V(KISTSchedRunInterval,        MSEC_INTERVAL, "0 msec"),
  V(KISTSockBufSizeFactor,       DOUBLE,   "1.0"),
  V(Schedulers,                  CSV,      "KIST,KISTLite,Vanilla"),
  V(ShutdownWaitLength,          INTERVAL, "30 seconds"),
  OBSOLETE("SocksListenAddress"),
  V(SocksPolicy,                 LINELIST, NULL),
  VPORT(SocksPort),
  V(SocksTimeout,                INTERVAL, "2 minutes"),
  V(SSLKeyLifetime,              INTERVAL, "0"),
  OBSOLETE("StrictEntryNodes"),
  OBSOLETE("StrictExitNodes"),
  V(StrictNodes,                 BOOL,     "0"),
  OBSOLETE("Support022HiddenServices"),
  V(TestSocks,                   BOOL,     "0"),
  V(TokenBucketRefillInterval,   MSEC_INTERVAL, "100 msec"),
  OBSOLETE("Tor2webMode"),
  OBSOLETE("Tor2webRendezvousPoints"),
  OBSOLETE("TLSECGroup"),
  V(TrackHostExits,              CSV,      NULL),
  V(TrackHostExitsExpire,        INTERVAL, "30 minutes"),
  OBSOLETE("TransListenAddress"),
  VPORT(TransPort),
  V(TransProxyType,              STRING,   "default"),
  OBSOLETE("TunnelDirConns"),
  V(UpdateBridgesFromAuthority,  BOOL,     "0"),
  V(UseBridges,                  BOOL,     "0"),
  VAR("UseEntryGuards",          BOOL,     UseEntryGuards_option, "1"),
  OBSOLETE("UseEntryGuardsAsDirGuards"),
  V(UseGuardFraction,            AUTOBOOL, "auto"),
  V(UseMicrodescriptors,         AUTOBOOL, "auto"),
  OBSOLETE("UseNTorHandshake"),
  V(User,                        STRING,   NULL),
  OBSOLETE("UserspaceIOCPBuffers"),
  V(AuthDirSharedRandomness,     BOOL,     "1"),
  V(AuthDirTestEd25519LinkKeys,  BOOL,     "1"),
  OBSOLETE("V1AuthoritativeDirectory"),
  OBSOLETE("V2AuthoritativeDirectory"),
  VAR("V3AuthoritativeDirectory",BOOL, V3AuthoritativeDir,   "0"),
  V(TestingV3AuthInitialVotingInterval, INTERVAL, "30 minutes"),
  V(TestingV3AuthInitialVoteDelay, INTERVAL, "5 minutes"),
  V(TestingV3AuthInitialDistDelay, INTERVAL, "5 minutes"),
  V(TestingV3AuthVotingStartOffset, INTERVAL, "0"),
  V(V3AuthVotingInterval,        INTERVAL, "1 hour"),
  V(V3AuthVoteDelay,             INTERVAL, "5 minutes"),
  V(V3AuthDistDelay,             INTERVAL, "5 minutes"),
  V(V3AuthNIntervalsValid,       UINT,     "3"),
  V(V3AuthUseLegacyKey,          BOOL,     "0"),
  V(V3BandwidthsFile,            FILENAME, NULL),
  V(GuardfractionFile,           FILENAME, NULL),
  VAR("VersioningAuthoritativeDirectory",BOOL,VersioningAuthoritativeDir, "0"),
  OBSOLETE("VoteOnHidServDirectoriesV2"),
  V(VirtualAddrNetworkIPv4,      STRING,   "127.192.0.0/10"),
  V(VirtualAddrNetworkIPv6,      STRING,   "[FE80::]/10"),
  V(WarnPlaintextPorts,          CSV,      "23,109,110,143"),
  OBSOLETE("UseFilteringSSLBufferevents"),
  OBSOLETE("__UseFilteringSSLBufferevents"),
  VAR("__ReloadTorrcOnSIGHUP",   BOOL,  ReloadTorrcOnSIGHUP,      "1"),
  VAR("__AllDirActionsPrivate",  BOOL,  AllDirActionsPrivate,     "0"),
  VAR("__DisablePredictedCircuits",BOOL,DisablePredictedCircuits, "0"),
  VAR("__DisableSignalHandlers", BOOL,  DisableSignalHandlers,    "0"),
  VAR("__LeaveStreamsUnattached",BOOL,  LeaveStreamsUnattached,   "0"),
  VAR("__HashedControlSessionPassword", LINELIST, HashedControlSessionPassword,
      NULL),
  VAR("__OwningControllerProcess",STRING,OwningControllerProcess, NULL),
  VAR("__OwningControllerFD", UINT64, OwningControllerFD, UINT64_MAX_STRING),
  V(MinUptimeHidServDirectoryV2, INTERVAL, "96 hours"),
  V(TestingServerDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingClientDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingServerConsensusDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingClientConsensusDownloadInitialDelay, CSV_INTERVAL, "0"),
  /* With the ClientBootstrapConsensus*Download* below:
   * Clients with only authorities will try:
   *  - at least 3 authorities over 10 seconds, then exponentially backoff,
   *    with the next attempt 3-21 seconds later,
   * Clients with authorities and fallbacks will try:
   *  - at least 2 authorities and 4 fallbacks over 21 seconds, then
   *    exponentially backoff, with the next attempts 4-33 seconds later,
   * Clients will also retry when an application request arrives.
   * After a number of failed requests, clients retry every 3 days + 1 hour.
   *
   * Clients used to try 2 authorities over 10 seconds, then wait for
   * 60 minutes or an application request.
   *
   * When clients have authorities and fallbacks available, they use these
   * schedules: (we stagger the times to avoid thundering herds) */
  V(ClientBootstrapConsensusAuthorityDownloadInitialDelay, CSV_INTERVAL, "6"),
  V(ClientBootstrapConsensusFallbackDownloadInitialDelay, CSV_INTERVAL, "0"),
  /* When clients only have authorities available, they use this schedule: */
  V(ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay, CSV_INTERVAL,
    "0"),
  /* We don't want to overwhelm slow networks (or mirrors whose replies are
   * blocked), but we also don't want to fail if only some mirrors are
   * blackholed. Clients will try 3 directories simultaneously.
   * (Relays never use simultaneous connections.) */
  V(ClientBootstrapConsensusMaxInProgressTries, UINT, "3"),
  /* When a client has any running bridges, check each bridge occasionally,
    * whether or not that bridge is actually up. */
  V(TestingBridgeDownloadInitialDelay, CSV_INTERVAL,"10800"),
  /* When a client is just starting, or has no running bridges, check each
   * bridge a few times quickly, and then try again later. These schedules
   * are much longer than the other schedules, because we try each and every
   * configured bridge with this schedule. */
  V(TestingBridgeBootstrapDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingClientMaxIntervalWithoutRequest, INTERVAL, "10 minutes"),
  V(TestingDirConnectionMaxStall, INTERVAL, "5 minutes"),
  OBSOLETE("TestingConsensusMaxDownloadTries"),
  OBSOLETE("ClientBootstrapConsensusMaxDownloadTries"),
  OBSOLETE("ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries"),
  OBSOLETE("TestingDescriptorMaxDownloadTries"),
  OBSOLETE("TestingMicrodescMaxDownloadTries"),
  OBSOLETE("TestingCertMaxDownloadTries"),
  V(TestingDirAuthVoteExit, ROUTERSET, NULL),
  V(TestingDirAuthVoteExitIsStrict,  BOOL,     "0"),
  V(TestingDirAuthVoteGuard, ROUTERSET, NULL),
  V(TestingDirAuthVoteGuardIsStrict,  BOOL,     "0"),
  V(TestingDirAuthVoteHSDir, ROUTERSET, NULL),
  V(TestingDirAuthVoteHSDirIsStrict,  BOOL,     "0"),
  VAR("___UsingTestNetworkDefaults", BOOL, UsingTestNetworkDefaults_, "0"),

  END_OF_CONFIG_VARS
};

/** Override default values with these if the user sets the TestingTorNetwork
 * option. */
static const config_var_t testing_tor_network_defaults[] = {
  V(DirAllowPrivateAddresses,    BOOL,     "1"),
  V(EnforceDistinctSubnets,      BOOL,     "0"),
  V(AssumeReachable,             BOOL,     "1"),
  V(AuthDirMaxServersPerAddr,    UINT,     "0"),
  V(ClientBootstrapConsensusAuthorityDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(ClientBootstrapConsensusFallbackDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(ClientBootstrapConsensusAuthorityOnlyDownloadInitialDelay, CSV_INTERVAL,
    "0"),
  V(ClientDNSRejectInternalAddresses, BOOL,"0"),
  V(ClientRejectInternalAddresses, BOOL,   "0"),
  V(CountPrivateBandwidth,       BOOL,     "1"),
  V(ExitPolicyRejectPrivate,     BOOL,     "0"),
  V(ExtendAllowPrivateAddresses, BOOL,     "1"),
  V(V3AuthVotingInterval,        INTERVAL, "5 minutes"),
  V(V3AuthVoteDelay,             INTERVAL, "20 seconds"),
  V(V3AuthDistDelay,             INTERVAL, "20 seconds"),
  V(TestingV3AuthInitialVotingInterval, INTERVAL, "150 seconds"),
  V(TestingV3AuthInitialVoteDelay, INTERVAL, "20 seconds"),
  V(TestingV3AuthInitialDistDelay, INTERVAL, "20 seconds"),
  V(TestingAuthDirTimeToLearnReachability, INTERVAL, "0 minutes"),
  V(TestingEstimatedDescriptorPropagationTime, INTERVAL, "0 minutes"),
  V(MinUptimeHidServDirectoryV2, INTERVAL, "0 minutes"),
  V(TestingServerDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingClientDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingServerConsensusDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingClientConsensusDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingBridgeDownloadInitialDelay, CSV_INTERVAL, "10"),
  V(TestingBridgeBootstrapDownloadInitialDelay, CSV_INTERVAL, "0"),
  V(TestingClientMaxIntervalWithoutRequest, INTERVAL, "5 seconds"),
  V(TestingDirConnectionMaxStall, INTERVAL, "30 seconds"),
  V(TestingEnableConnBwEvent,    BOOL,     "1"),
  V(TestingEnableCellStatsEvent, BOOL,     "1"),
  VAR("___UsingTestNetworkDefaults", BOOL, UsingTestNetworkDefaults_, "1"),
  V(RendPostPeriod,              INTERVAL, "2 minutes"),

  END_OF_CONFIG_VARS
};

#undef VAR
#undef V
#undef OBSOLETE

static const config_deprecation_t option_deprecation_notes_[] = {
  /* Deprecated since 0.3.2.0-alpha. */
  { "HTTPProxy", "It only applies to direct unencrypted HTTP connections "
    "to your directory server, which your Tor probably wasn't using." },
  { "HTTPProxyAuthenticator", "HTTPProxy is deprecated in favor of HTTPSProxy "
    "which should be used with HTTPSProxyAuthenticator." },
  /* End of options deprecated since 0.3.2.1-alpha */

  /* Options deprecated since 0.3.2.2-alpha */
  { "ReachableDirAddresses", "It has no effect on relays, and has had no "
    "effect on clients since 0.2.8." },
  { "ClientPreferIPv6DirPort", "It has no effect on relays, and has had no "
    "effect on clients since 0.2.8." },
  /* End of options deprecated since 0.3.2.2-alpha. */

  { NULL, NULL }
};

#ifdef _WIN32
static char *get_windows_conf_root(void);
#endif
static int options_act_reversible(const or_options_t *old_options, char **msg);
static int options_transition_allowed(const or_options_t *old,
                                      const or_options_t *new,
                                      char **msg);
static int options_transition_affects_workers(
      const or_options_t *old_options, const or_options_t *new_options);
static int options_transition_affects_descriptor(
      const or_options_t *old_options, const or_options_t *new_options);