config.c

/* Copyright (c) 2001 Matej Pfajfar.
 * Copyright (c) 2001-2004, Roger Dingledine.
 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
 * Copyright (c) 2007-2011, The Tor Project, Inc. */
/* See LICENSE for licensing information */

/**
 * \file config.c
 * \brief Code to parse and interpret configuration files.
 **/

#define CONFIG_PRIVATE

#include "or.h"
#include "circuitbuild.h"
#include "circuitlist.h"
#include "config.h"
#include "connection.h"
#include "connection_edge.h"
#include "connection_or.h"
#include "control.h"
#include "cpuworker.h"
#include "dirserv.h"
#include "dirvote.h"
#include "dns.h"
#include "geoip.h"
#include "hibernate.h"
#include "main.h"
#include "networkstatus.h"
#include "policies.h"
#include "relay.h"
#include "rendclient.h"
#include "rendservice.h"
#include "rephist.h"
#include "router.h"
#include "util.h"
#include "routerlist.h"
#include "transports.h"
#ifdef MS_WINDOWS
#include <shlobj.h>
#endif

#include "procmon.h"

/* From main.c */
extern int quiet_level;

/* Includes for the process attaching prevention */
#if defined(HAVE_SYS_PRCTL_H) && defined(__linux__)
#include <sys/prctl.h> 
#elif defined(__APPLE__)
#include <sys/types.h>
#include <sys/ptrace.h>
#endif

/** Enumeration of types which option values can take */
typedef enum config_type_t {
  CONFIG_TYPE_STRING = 0,   /**< An arbitrary string. */
  CONFIG_TYPE_FILENAME,     /**< A filename: some prefixes get expanded. */
  CONFIG_TYPE_UINT,         /**< A non-negative integer less than MAX_INT */
  CONFIG_TYPE_PORT,         /**< A port from 1...65535, 0 for "not set", or
                             * "auto".  */
  CONFIG_TYPE_INTERVAL,     /**< A number of seconds, with optional units*/
  CONFIG_TYPE_MSEC_INTERVAL,/**< A number of milliseconds, with optional
                              * units */
  CONFIG_TYPE_MEMUNIT,      /**< A number of bytes, with optional units*/
  CONFIG_TYPE_DOUBLE,       /**< A floating-point value */
  CONFIG_TYPE_BOOL,         /**< A boolean value, expressed as 0 or 1. */
  CONFIG_TYPE_AUTOBOOL,     /**< A boolean+auto value, expressed 0 for false,
                             * 1 for true, and -1 for auto  */
  CONFIG_TYPE_ISOTIME,      /**< An ISO-formatted time relative to GMT. */
  CONFIG_TYPE_CSV,          /**< A list of strings, separated by commas and
                              * optional whitespace. */
  CONFIG_TYPE_LINELIST,     /**< Uninterpreted config lines */
  CONFIG_TYPE_LINELIST_S,   /**< Uninterpreted, context-sensitive config lines,
                             * mixed with other keywords. */
  CONFIG_TYPE_LINELIST_V,   /**< Catch-all "virtual" option to summarize
                             * context-sensitive config lines when fetching.
                             */
  CONFIG_TYPE_ROUTERSET,    /**< A list of router names, addrs, and fps,
                             * parsed into a routerset_t. */
  CONFIG_TYPE_OBSOLETE,     /**< Obsolete (ignored) option. */
} config_type_t;

/** An abbreviation for a configuration option allowed on the command line. */
typedef struct config_abbrev_t {
  const char *abbreviated;
  const char *full;
  int commandline_only;
  int warn;
} config_abbrev_t;

/* Handy macro for declaring "In the config file or on the command line,
 * you can abbreviate <b>tok</b>s as <b>tok</b>". */
#define PLURAL(tok) { #tok, #tok "s", 0, 0 }

/** 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(ExitNode),
  PLURAL(EntryNode),
  PLURAL(ExcludeNode),
  PLURAL(FirewallPort),
  PLURAL(LongLivedPort),
  PLURAL(HiddenServiceNode),
  PLURAL(HiddenServiceExcludeNode),
  PLURAL(NumCPU),
  PLURAL(RendNode),
  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},
  { "MaxConn", "ConnLimit", 0, 1},
  { "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},
  { "StrictEntryNodes", "StrictNodes", 0, 1},
  { "StrictExitNodes", "StrictNodes", 0, 1},
  { NULL, NULL, 0, 0},
};

/** A list of state-file "abbreviations," for compatibility. */
static config_abbrev_t _state_abbrevs[] = {
  { "AccountingBytesReadInterval", "AccountingBytesReadInInterval", 0, 0 },
  { "HelperNode", "EntryGuard", 0, 0 },
  { "HelperNodeDownSince", "EntryGuardDownSince", 0, 0 },
  { "HelperNodeUnlistedSince", "EntryGuardUnlistedSince", 0, 0 },
  { "EntryNode", "EntryGuard", 0, 0 },
  { "EntryNodeDownSince", "EntryGuardDownSince", 0, 0 },
  { "EntryNodeUnlistedSince", "EntryGuardUnlistedSince", 0, 0 },
  { NULL, NULL, 0, 0},
};
#undef PLURAL

/** A variable allowed in the configuration file or on the command line. */
typedef struct config_var_t {
  const char *name; /**< The full keyword (case insensitive). */
  config_type_t type; /**< How to interpret the type and turn it into a
                       * value. */
  off_t var_offset; /**< Offset of the corresponding member of or_options_t. */
  const char *initvalue; /**< String (or null) describing initial value. */
} config_var_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, STRUCT_OFFSET(or_options_t, member), \
      initvalue }
/** 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." */
#define OBSOLETE(name) { name, CONFIG_TYPE_OBSOLETE, 0, NULL }

/** 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[] = {
  OBSOLETE("AccountingMaxKB"),
  V(AccountingMax,               MEMUNIT,  "0 bytes"),
  V(AccountingStart,             STRING,   NULL),
  V(Address,                     STRING,   NULL),
  V(AllowDotExit,                BOOL,     "0"),
  V(AllowInvalidNodes,           CSV,      "middle,rendezvous"),
  V(AllowNonRFC953Hostnames,     BOOL,     "0"),
  V(AllowSingleHopCircuits,      BOOL,     "0"),
  V(AllowSingleHopExits,         BOOL,     "0"),
  V(AlternateBridgeAuthority,    LINELIST, NULL),
  V(AlternateDirAuthority,       LINELIST, NULL),
  V(AlternateHSAuthority,        LINELIST, NULL),
  V(AssumeReachable,             BOOL,     "0"),
  V(AuthDirBadDir,               LINELIST, NULL),
  V(AuthDirBadExit,              LINELIST, NULL),
  V(AuthDirInvalid,              LINELIST, NULL),
  V(AuthDirFastGuarantee,        MEMUNIT,  "100 KB"),
  V(AuthDirGuardBWGuarantee,     MEMUNIT,  "250 KB"),
  V(AuthDirReject,               LINELIST, NULL),
  V(AuthDirRejectUnlisted,       BOOL,     "0"),
  V(AuthDirListBadDirs,          BOOL,     "0"),
  V(AuthDirListBadExits,         BOOL,     "0"),
  V(AuthDirMaxServersPerAddr,    UINT,     "2"),
  V(AuthDirMaxServersPerAuthAddr,UINT,     "5"),
  VAR("AuthoritativeDirectory",  BOOL, AuthoritativeDir,    "0"),
  V(AutomapHostsOnResolve,       BOOL,     "0"),
  V(AutomapHostsSuffixes,        CSV,      ".onion,.exit"),
  V(AvoidDiskWrites,             BOOL,     "0"),
  V(BandwidthBurst,              MEMUNIT,  "10 MB"),
  V(BandwidthRate,               MEMUNIT,  "5 MB"),
  V(BridgeAuthoritativeDir,      BOOL,     "0"),
  VAR("Bridge",                  LINELIST, Bridges,    NULL),
  V(BridgePassword,              STRING,   NULL),
  V(BridgeRecordUsageByCountry,  BOOL,     "1"),
  V(BridgeRelay,                 BOOL,     "0"),
  V(CellStatistics,              BOOL,     "0"),
  V(LearnCircuitBuildTimeout,    BOOL,     "1"),
  V(CircuitBuildTimeout,         INTERVAL, "0"),
  V(CircuitIdleTimeout,          INTERVAL, "1 hour"),
  V(CircuitStreamTimeout,        INTERVAL, "0"),
  V(CircuitPriorityHalflife,     DOUBLE,  "-100.0"), /*negative:'Use default'*/
  V(ClientDNSRejectInternalAddresses, BOOL,"1"),
  V(ClientOnly,                  BOOL,     "0"),
  V(ClientRejectInternalAddresses, BOOL,   "1"),
  V(ClientTransportPlugin,       LINELIST, NULL),
  V(ConsensusParams,             STRING,   NULL),
  V(ConnLimit,                   UINT,     "1000"),
  V(ConnDirectionStatistics,     BOOL,     "0"),
  V(ConstrainedSockets,          BOOL,     "0"),
  V(ConstrainedSockSize,         MEMUNIT,  "8192"),
  V(ContactInfo,                 STRING,   NULL),
  V(ControlListenAddress,        LINELIST, NULL),
  V(ControlPort,                 PORT,     "0"),
  V(ControlPortFileGroupReadable,BOOL,     "0"),
  V(ControlPortWriteToFile,      FILENAME, NULL),
  V(ControlSocket,               LINELIST, NULL),
  V(ControlSocketsGroupWritable, BOOL,     "0"),
  V(CookieAuthentication,        BOOL,     "0"),
  V(CookieAuthFileGroupReadable, BOOL,     "0"),
  V(CookieAuthFile,              STRING,   NULL),
  V(CountPrivateBandwidth,       BOOL,     "0"),
  V(DataDirectory,               FILENAME, NULL),
  OBSOLETE("DebugLogFile"),
  V(DirAllowPrivateAddresses,    BOOL,     NULL),
  V(TestingAuthDirTimeToLearnReachability, INTERVAL, "30 minutes"),
  V(DirListenAddress,            LINELIST, NULL),
  OBSOLETE("DirFetchPeriod"),
  V(DirPolicy,                   LINELIST, NULL),
  V(DirPort,                     PORT,     "0"),
  V(DirPortFrontPage,            FILENAME, NULL),
  OBSOLETE("DirPostPeriod"),
  OBSOLETE("DirRecordUsageByCountry"),
  OBSOLETE("DirRecordUsageGranularity"),
  OBSOLETE("DirRecordUsageRetainIPs"),
  OBSOLETE("DirRecordUsageSaveInterval"),
  V(DirReqStatistics,            BOOL,     "1"),
  VAR("DirServer",               LINELIST, DirServers, NULL),
  V(DisableAllSwap,              BOOL,     "0"),
  V(DisableDebuggerAttachment,   BOOL,     "1"),
  V(DisableIOCP,                 BOOL,     "1"),
  V(DNSPort,                     LINELIST, NULL),
  V(DNSListenAddress,            LINELIST, NULL),
  V(DownloadExtraInfo,           BOOL,     "0"),
  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),
  V(ExcludeSingleHopRelays,      BOOL,     "1"),
  V(ExitNodes,                   ROUTERSET, NULL),
  V(ExitPolicy,                  LINELIST, NULL),
  V(ExitPolicyRejectPrivate,     BOOL,     "1"),
  V(ExitPortStatistics,          BOOL,     "0"),
  V(ExtraInfoStatistics,         BOOL,     "1"),

#if defined (WINCE)
  V(FallbackNetworkstatusFile,   FILENAME, "fallback-consensus"),
#else
  V(FallbackNetworkstatusFile,   FILENAME,
    SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "fallback-consensus"),
#endif
  V(FascistFirewall,             BOOL,     "0"),
  V(FirewallPorts,               CSV,      ""),
  V(FastFirstHopPK,              BOOL,     "1"),
  V(FetchDirInfoEarly,           BOOL,     "0"),
  V(FetchDirInfoExtraEarly,      BOOL,     "0"),
  V(FetchServerDescriptors,      BOOL,     "1"),
  V(FetchHidServDescriptors,     BOOL,     "1"),
  V(FetchUselessDescriptors,     BOOL,     "0"),
  V(FetchV2Networkstatus,        BOOL,     "0"),
#ifdef WIN32
  V(GeoIPFile,                   FILENAME, "<default>"),
#else
  V(GeoIPFile,                   FILENAME,
    SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "geoip"),
#endif
  V(GiveGuardFlagTo_CVE_2011_2768_VulnerableRelays,
                                 BOOL,     "0"),
  OBSOLETE("Group"),
  V(HardwareAccel,               BOOL,     "0"),
  V(HeartbeatPeriod,             INTERVAL, "6 hours"),
  V(AccelName,                   STRING,   NULL),
  V(AccelDir,                    FILENAME, NULL),
  V(HashedControlPassword,       LINELIST, NULL),
  V(HidServDirectoryV2,          BOOL,     "1"),
  VAR("HiddenServiceDir",    LINELIST_S, RendConfigLines,    NULL),
  OBSOLETE("HiddenServiceExcludeNodes"),
  OBSOLETE("HiddenServiceNodes"),
  VAR("HiddenServiceOptions",LINELIST_V, RendConfigLines,    NULL),
  VAR("HiddenServicePort",   LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceVersion",LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceAuthorizeClient",LINELIST_S,RendConfigLines, NULL),
  V(HidServAuth,                 LINELIST, NULL),
  V(HSAuthoritativeDir,          BOOL,     "0"),
  OBSOLETE("HSAuthorityRecordStats"),
  V(HTTPProxy,                   STRING,   NULL),
  V(HTTPProxyAuthenticator,      STRING,   NULL),
  V(HTTPSProxy,                  STRING,   NULL),
  V(HTTPSProxyAuthenticator,     STRING,   NULL),
  VAR("ServerTransportPlugin",   LINELIST, ServerTransportPlugin,  NULL),
  V(Socks4Proxy,                 STRING,   NULL),
  V(Socks5Proxy,                 STRING,   NULL),
  V(Socks5ProxyUsername,         STRING,   NULL),
  V(Socks5ProxyPassword,         STRING,   NULL),
  OBSOLETE("IgnoreVersion"),
  V(KeepalivePeriod,             INTERVAL, "5 minutes"),
  VAR("Log",                     LINELIST, Logs,             NULL),
  V(LogMessageDomains,           BOOL,     "0"),
  OBSOLETE("LinkPadding"),
  OBSOLETE("LogLevel"),
  OBSOLETE("LogFile"),
  V(LogTimeGranularity,          MSEC_INTERVAL, "1 second"),
  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(MaxOnionsPending,            UINT,     "100"),
  OBSOLETE("MonthlyAccountingStart"),
  V(MyFamily,                    STRING,   NULL),
  V(NewCircuitPeriod,            INTERVAL, "30 seconds"),
  VAR("NamingAuthoritativeDirectory",BOOL, NamingAuthoritativeDir, "0"),
  V(NATDListenAddress,           LINELIST, NULL),
  V(NATDPort,                    LINELIST, NULL),
  V(Nickname,                    STRING,   NULL),
  V(WarnUnsafeSocks,              BOOL,     "1"),
  OBSOLETE("NoPublish"),
  VAR("NodeFamily",              LINELIST, NodeFamilies,         NULL),
  V(NumCPUs,                     UINT,     "0"),
  V(NumEntryGuards,              UINT,     "3"),
  V(ORListenAddress,             LINELIST, NULL),
  V(ORPort,                      PORT,     "0"),
  V(OutboundBindAddress,         STRING,   NULL),
  OBSOLETE("PathlenCoinWeight"),
  V(PerConnBWBurst,              MEMUNIT,  "0"),
  V(PerConnBWRate,               MEMUNIT,  "0"),
  V(PidFile,                     STRING,   NULL),
  V(TestingTorNetwork,           BOOL,     "0"),
  V(OptimisticData,              AUTOBOOL, "auto"),
  V(PortForwarding,              BOOL,     "0"),
  V(PortForwardingHelper,        FILENAME, "tor-fw-helper"),
  V(PreferTunneledDirConns,      BOOL,     "1"),
  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),
  OBSOLETE("RedirectExit"),
  V(RefuseUnknownExits,          AUTOBOOL, "auto"),
  V(RejectPlaintextPorts,        CSV,      ""),
  V(RelayBandwidthBurst,         MEMUNIT,  "0"),
  V(RelayBandwidthRate,          MEMUNIT,  "0"),
  OBSOLETE("RendExcludeNodes"),
  OBSOLETE("RendNodes"),
  V(RendPostPeriod,              INTERVAL, "1 hour"),
  V(RephistTrackTime,            INTERVAL, "24 hours"),
  OBSOLETE("RouterFile"),
  V(RunAsDaemon,                 BOOL,     "0"),
//  V(RunTesting,                  BOOL,     "0"),
  OBSOLETE("RunTesting"), // currently unused
  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"),
  V(ShutdownWaitLength,          INTERVAL, "30 seconds"),
  V(SocksListenAddress,          LINELIST, NULL),
  V(SocksPolicy,                 LINELIST, NULL),
  V(SocksPort,                   LINELIST, NULL),
  V(SocksTimeout,                INTERVAL, "2 minutes"),
  OBSOLETE("StatusFetchPeriod"),
  V(StrictNodes,                 BOOL,     "0"),
  OBSOLETE("SysLog"),
  V(TestSocks,                   BOOL,     "0"),
  OBSOLETE("TestVia"),
  V(TokenBucketRefillInterval,   MSEC_INTERVAL, "100 msec"),
  V(TrackHostExits,              CSV,      NULL),
  V(TrackHostExitsExpire,        INTERVAL, "30 minutes"),
  OBSOLETE("TrafficShaping"),
  V(TransListenAddress,          LINELIST, NULL),
  V(TransPort,                   LINELIST, NULL),
  V(TunnelDirConns,              BOOL,     "1"),
  V(UpdateBridgesFromAuthority,  BOOL,     "0"),
  V(UseBridges,                  BOOL,     "0"),
  V(UseEntryGuards,              BOOL,     "1"),
  V(UseMicrodescriptors,         AUTOBOOL, "auto"),
  V(User,                        STRING,   NULL),
  V(UserspaceIOCPBuffers,        BOOL,     "0"),
  VAR("V1AuthoritativeDirectory",BOOL, V1AuthoritativeDir,   "0"),
  VAR("V2AuthoritativeDirectory",BOOL, V2AuthoritativeDir,   "0"),
  VAR("V3AuthoritativeDirectory",BOOL, V3AuthoritativeDir,   "0"),
  V(TestingV3AuthInitialVotingInterval, INTERVAL, "30 minutes"),
  V(TestingV3AuthInitialVoteDelay, INTERVAL, "5 minutes"),
  V(TestingV3AuthInitialDistDelay, INTERVAL, "5 minutes"),
  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),
  VAR("VersioningAuthoritativeDirectory",BOOL,VersioningAuthoritativeDir, "0"),
  V(VirtualAddrNetwork,          STRING,   "127.192.0.0/10"),
  V(WarnPlaintextPorts,          CSV,      "23,109,110,143"),
  V(_UseFilteringSSLBufferevents, BOOL,    "0"),
  VAR("__ReloadTorrcOnSIGHUP",   BOOL,  ReloadTorrcOnSIGHUP,      "1"),
  VAR("__AllDirActionsPrivate",  BOOL,  AllDirActionsPrivate,     "0"),
  VAR("__DisablePredictedCircuits",BOOL,DisablePredictedCircuits, "0"),
  VAR("__LeaveStreamsUnattached",BOOL,  LeaveStreamsUnattached,   "0"),
  VAR("__HashedControlSessionPassword", LINELIST, HashedControlSessionPassword,
      NULL),
  VAR("__OwningControllerProcess",STRING,OwningControllerProcess, NULL),
  V(MinUptimeHidServDirectoryV2, INTERVAL, "25 hours"),
  V(VoteOnHidServDirectoriesV2,  BOOL,     "1"),
  V(_UsingTestNetworkDefaults,   BOOL,     "0"),

  { NULL, CONFIG_TYPE_OBSOLETE, 0, NULL }
};

/** Override default values with these if the user sets the TestingTorNetwork
 * option. */
static const config_var_t testing_tor_network_defaults[] = {
  V(ServerDNSAllowBrokenConfig,  BOOL,  "1"),
  V(DirAllowPrivateAddresses,    BOOL,     "1"),
  V(EnforceDistinctSubnets,      BOOL,     "0"),
  V(AssumeReachable,             BOOL,     "1"),
  V(AuthDirMaxServersPerAddr,    UINT,     "0"),
  V(AuthDirMaxServersPerAuthAddr,UINT,     "0"),
  V(ClientDNSRejectInternalAddresses, BOOL,"0"),
  V(ClientRejectInternalAddresses, BOOL,   "0"),
  V(CountPrivateBandwidth,       BOOL,     "1"),
  V(ExitPolicyRejectPrivate,     BOOL,     "0"),
  V(V3AuthVotingInterval,        INTERVAL, "5 minutes"),
  V(V3AuthVoteDelay,             INTERVAL, "20 seconds"),
  V(V3AuthDistDelay,             INTERVAL, "20 seconds"),
  V(TestingV3AuthInitialVotingInterval, INTERVAL, "5 minutes"),
  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(_UsingTestNetworkDefaults,   BOOL,     "1"),

  { NULL, CONFIG_TYPE_OBSOLETE, 0, NULL }
};
#undef VAR

#define VAR(name,conftype,member,initvalue)                             \
  { name, CONFIG_TYPE_ ## conftype, STRUCT_OFFSET(or_state_t, member),  \
      initvalue }

/** Array of "state" variables saved to the ~/.tor/state file. */
static config_var_t _state_vars[] = {
  V(AccountingBytesReadInInterval,    MEMUNIT,  NULL),
  V(AccountingBytesWrittenInInterval, MEMUNIT,  NULL),
  V(AccountingExpectedUsage,          MEMUNIT,  NULL),
  V(AccountingIntervalStart,          ISOTIME,  NULL),
  V(AccountingSecondsActive,          INTERVAL, NULL),
  V(AccountingSecondsToReachSoftLimit,INTERVAL, NULL),
  V(AccountingSoftLimitHitAt,         ISOTIME,  NULL),
  V(AccountingBytesAtSoftLimit,       MEMUNIT,  NULL),

  VAR("EntryGuard",              LINELIST_S,  EntryGuards,             NULL),
  VAR("EntryGuardDownSince",     LINELIST_S,  EntryGuards,             NULL),
  VAR("EntryGuardUnlistedSince", LINELIST_S,  EntryGuards,             NULL),
  VAR("EntryGuardAddedBy",       LINELIST_S,  EntryGuards,             NULL),
  V(EntryGuards,                 LINELIST_V,  NULL),

  VAR("TransportProxy",               LINELIST_S, TransportProxies, NULL),
  V(TransportProxies,                 LINELIST_V, NULL),

  V(BWHistoryReadEnds,                ISOTIME,  NULL),
  V(BWHistoryReadInterval,            UINT,     "900"),
  V(BWHistoryReadValues,              CSV,      ""),
  V(BWHistoryReadMaxima,              CSV,      ""),
  V(BWHistoryWriteEnds,               ISOTIME,  NULL),
  V(BWHistoryWriteInterval,           UINT,     "900"),
  V(BWHistoryWriteValues,             CSV,      ""),
  V(BWHistoryWriteMaxima,             CSV,      ""),
  V(BWHistoryDirReadEnds,             ISOTIME,  NULL),
  V(BWHistoryDirReadInterval,         UINT,     "900"),
  V(BWHistoryDirReadValues,           CSV,      ""),
  V(BWHistoryDirReadMaxima,           CSV,      ""),
  V(BWHistoryDirWriteEnds,            ISOTIME,  NULL),
  V(BWHistoryDirWriteInterval,        UINT,     "900"),
  V(BWHistoryDirWriteValues,          CSV,      ""),
  V(BWHistoryDirWriteMaxima,          CSV,      ""),

  V(TorVersion,                       STRING,   NULL),

  V(LastRotatedOnionKey,              ISOTIME,  NULL),
  V(LastWritten,                      ISOTIME,  NULL),

  V(TotalBuildTimes,                  UINT,     NULL),
  V(CircuitBuildAbandonedCount,       UINT,     "0"),
  VAR("CircuitBuildTimeBin",          LINELIST_S, BuildtimeHistogram, NULL),
  VAR("BuildtimeHistogram",           LINELIST_V, BuildtimeHistogram, NULL),
  { NULL, CONFIG_TYPE_OBSOLETE, 0, NULL }
};

#undef VAR
#undef V
#undef OBSOLETE

/** Represents an English description of a configuration variable; used when
 * generating configuration file comments. */
typedef struct config_var_description_t {
  const char *name;
  const char *description;
} config_var_description_t;

/** Type of a callback to validate whether a given configuration is
 * well-formed and consistent. See options_trial_assign() for documentation
 * of arguments. */
typedef int (*validate_fn_t)(void*,void*,int,char**);

/** Information on the keys, value types, key-to-struct-member mappings,
 * variable descriptions, validation functions, and abbreviations for a
 * configuration or storage format. */
typedef struct {
  size_t size; /**< Size of the struct that everything gets parsed into. */
  uint32_t magic; /**< Required 'magic value' to make sure we have a struct
                   * of the right type. */
  off_t magic_offset; /**< Offset of the magic value within the struct. */
  config_abbrev_t *abbrevs; /**< List of abbreviations that we expand when
                             * parsing this format. */
  config_var_t *vars; /**< List of variables we recognize, their default
                       * values, and where we stick them in the structure. */
  validate_fn_t validate_fn; /**< Function to validate config. */
  /** If present, extra is a LINELIST variable for unrecognized
   * lines.  Otherwise, unrecognized lines are an error. */
  config_var_t *extra;
} config_format_t;

/** Macro: assert that <b>cfg</b> has the right magic field for format
 * <b>fmt</b>. */
#define CHECK(fmt, cfg) STMT_BEGIN                                      \
    tor_assert(fmt && cfg);                                             \
    tor_assert((fmt)->magic ==                                          \
               *(uint32_t*)STRUCT_VAR_P(cfg,fmt->magic_offset));        \
  STMT_END

#ifdef MS_WINDOWS
static char *get_windows_conf_root(void);
#endif
static void config_line_append(config_line_t **lst,
                               const char *key, const char *val);
static void option_clear(const config_format_t *fmt, or_options_t *options,
                         const config_var_t *var);
static void option_reset(const config_format_t *fmt, or_options_t *options,
                         const config_var_t *var, int use_defaults);
static void config_free(const config_format_t *fmt, void *options);
static int config_lines_eq(config_line_t *a, config_line_t *b);
static int option_is_same(const config_format_t *fmt,
                          const or_options_t *o1, const or_options_t *o2,
                          const char *name);
static or_options_t *options_dup(const config_format_t *fmt,
                                 const or_options_t *old);
static int options_validate(or_options_t *old_options,
                            or_options_t *options,
                            int from_setconf, char **msg);
static int options_act_reversible(const or_options_t *old_options, char **msg);
static int options_act(const or_options_t *old_options);
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);
static int check_nickname_list(const char *lst, const char *name, char **msg);

static int parse_bridge_line(const char *line, int validate_only);
static int parse_client_transport_line(const char *line, int validate_only);

static int parse_server_transport_line(const char *line, int validate_only);
static int parse_dir_server_line(const char *line,
                                 dirinfo_type_t required_type,
                                 int validate_only);
static void port_cfg_free(port_cfg_t *port);
static int parse_client_ports(const or_options_t *options, int validate_only,
                              char **msg_out, int *n_ports_out);
static int validate_data_directory(or_options_t *options);
static int write_configuration_file(const char *fname,
                                    const or_options_t *options);
static config_line_t *get_assigned_option(const config_format_t *fmt,
                                        const void *options, const char *key,
                                        int escape_val);
static void config_init(const config_format_t *fmt, void *options);
static int or_state_validate(or_state_t *old_options, or_state_t *options,
                             int from_setconf, char **msg);
static int or_state_load(void);
static int options_init_logs(or_options_t *options, int validate_only);

static int is_listening_on_low_port(int port_option,
                                    const config_line_t *listen_options);

static uint64_t config_parse_memunit(const char *s, int *ok);
static int config_parse_msec_interval(const char *s, int *ok);
static int config_parse_interval(const char *s, int *ok);
static void init_libevent(const or_options_t *options);
static int opt_streq(const char *s1, const char *s2);

/** Magic value for or_options_t. */
#define OR_OPTIONS_MAGIC 9090909

/** Configuration format for or_options_t. */
static config_format_t options_format = {
  sizeof(or_options_t),
  OR_OPTIONS_MAGIC,
  STRUCT_OFFSET(or_options_t, _magic),
  _option_abbrevs,
  _option_vars,
  (validate_fn_t)options_validate,
  NULL
};

/** Magic value for or_state_t. */
#define OR_STATE_MAGIC 0x57A73f57

/** "Extra" variable in the state that receives lines we can't parse. This
 * lets us preserve options from versions of Tor newer than us. */
static config_var_t state_extra_var = {
  "__extra", CONFIG_TYPE_LINELIST, STRUCT_OFFSET(or_state_t, ExtraLines), NULL
};

/** Configuration format for or_state_t. */
static const config_format_t state_format = {
  sizeof(or_state_t),
  OR_STATE_MAGIC,
  STRUCT_OFFSET(or_state_t, _magic),
  _state_abbrevs,
  _state_vars,
  (validate_fn_t)or_state_validate,
  &state_extra_var,
};

/*
 * Functions to read and write the global options pointer.
 */

/** Command-line and config-file options. */
static or_options_t *global_options = NULL;
/** Name of most recently read torrc file. */
static char *torrc_fname = NULL;
/** Persistent serialized state. */
static or_state_t *global_state = NULL;
/** Configuration Options set by command line. */
static config_line_t *global_cmdline_options = NULL;
/** Contents of most recently read DirPortFrontPage file. */
static char *global_dirfrontpagecontents = NULL;
/** List of port_cfg_t for client-level (SOCKS, DNS, Trans, NATD) ports. */
static smartlist_t *configured_client_ports = NULL;

/** Return the contents of our frontpage string, or NULL if not configured. */
const char *
get_dirportfrontpage(void)
{
  return global_dirfrontpagecontents;
}

/* We only use the linux prctl for now. There is no Win32 support; this may
 * also work on various BSD systems and Mac OS X - send testing feedback!
 * 
 * On recent Gnu/Linux kernels it is possible to create a system-wide policy
 * that will prevent non-root processes from attaching to other processes
 * unless they are the parent process; thus gdb can attach to programs that
 * they execute but they cannot attach to other processes running as the same
 * user. The system wide policy may be set with the sysctl
 * kernel.yama.ptrace_scope or by inspecting /proc/sys/kernel/yama/ptrace_scope
 * and it is 1 by default on Ubuntu 11.04.
 *
 * This ptrace scope will be ignored on Gnu/Linux for users with
 * CAP_SYS_PTRACE and so it is very likely that root will still be able to
 * attach to the Tor process.
*/
/** Attempt to disable debugger attachment. */
static int tor_disable_debugger_attach(void) {
    int r;
    r = -1;
    log_debug(LD_CONFIG,
    "Attemping to disable debugger attachment to Tor for unprivileged users.");
#if defined(__linux__) && defined(HAVE_SYS_PRCTL_H) && defined(HAVE_PRCTL)
#ifdef PR_SET_DUMPABLE
    r = prctl(PR_SET_DUMPABLE, 0);
#endif
#endif
#if defined(__APPLE__) && defined(PT_DENY_ATTACH)
    r = ptrace(PT_DENY_ATTACH, 0, 0, 0);
#endif

// XXX: TODO - Mac OS X has dtrace and this may be disabled - implement it here
// XXX: TODO - Windows probably has something similar - implement it here
    if (r == 0) {
      log_debug(LD_CONFIG,"Debugger attachment disabled for unprivileged users.");
    } else {
      log_warn(LD_CONFIG, "Unable to disable ptrace attach: %s",
                          strerror(errno));
    }
    return r;
}

/** Allocate an empty configuration object of a given format type. */
static void *
config_alloc(const config_format_t *fmt)
{
  void *opts = tor_malloc_zero(fmt->size);
  *(uint32_t*)STRUCT_VAR_P(opts, fmt->magic_offset) = fmt->magic;
  CHECK(fmt, opts);
  return opts;
}

/** Return the currently configured options. */
or_options_t *
get_options_mutable(void)
{
  tor_assert(global_options);
  return global_options;
}

/** Returns the currently configured options */
const or_options_t *
get_options(void)
{
  return get_options_mutable();
}

/** Change the current global options to contain <b>new_val</b> instead of
 * their current value; take action based on the new value; free the old value
 * as necessary.  Returns 0 on success, -1 on failure.
 */
int
set_options(or_options_t *new_val, char **msg)
{
  int i;
  smartlist_t *elements;
  config_line_t *line;
  or_options_t *old_options = global_options;
  global_options = new_val;
  /* Note that we pass the *old* options below, for comparison. It
   * pulls the new options directly out of global_options. */
  if (options_act_reversible(old_options, msg)<0) {
    tor_assert(*msg);
    global_options = old_options;
    return -1;
  }
  if (options_act(old_options) < 0) { /* acting on the options failed. die. */
    log_err(LD_BUG,