config.c 168 KB
Newer Older
Roger Dingledine's avatar
Roger Dingledine committed
1
2
/* Copyright (c) 2001 Matej Pfajfar.
 * Copyright (c) 2001-2004, Roger Dingledine.
3
 * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
Roger Dingledine's avatar
Roger Dingledine committed
4
 * Copyright (c) 2007-2008, The Tor Project, Inc. */
5
6
/* See LICENSE for licensing information */
/* $Id$ */
7
8
const char config_c_id[] = \
  "$Id$";
9

Nick Mathewson's avatar
Nick Mathewson committed
10
/**
11
12
 * \file config.c
 * \brief Code to parse and interpret configuration files.
Nick Mathewson's avatar
Nick Mathewson committed
13
14
 **/

15
16
#define CONFIG_PRIVATE

Roger Dingledine's avatar
Roger Dingledine committed
17
#include "or.h"
18
19
20
#ifdef MS_WINDOWS
#include <shlobj.h>
#endif
Roger Dingledine's avatar
Roger Dingledine committed
21

Nick Mathewson's avatar
Nick Mathewson committed
22
23
/** Enumeration of types which option values can take */
typedef enum config_type_t {
24
25
  CONFIG_TYPE_STRING = 0,   /**< An arbitrary string. */
  CONFIG_TYPE_UINT,         /**< A non-negative integer less than MAX_INT */
26
27
  CONFIG_TYPE_INTERVAL,     /**< A number of seconds, with optional units*/
  CONFIG_TYPE_MEMUNIT,      /**< A number of bytes, with optional units*/
28
29
  CONFIG_TYPE_DOUBLE,       /**< A floating-point value */
  CONFIG_TYPE_BOOL,         /**< A boolean value, expressed as 0 or 1. */
30
  CONFIG_TYPE_ISOTIME,      /**< An ISO-formated time relative to GMT. */
31
32
  CONFIG_TYPE_CSV,          /**< A list of strings, separated by commas and
                              * optional whitespace. */
33
  CONFIG_TYPE_LINELIST,     /**< Uninterpreted config lines */
34
35
36
37
38
  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.
                             */
39
  CONFIG_TYPE_OBSOLETE,     /**< Obsolete (ignored) option. */
Nick Mathewson's avatar
Nick Mathewson committed
40
} config_type_t;
41

42
/** An abbreviation for a configuration option allowed on the command line. */
43
typedef struct config_abbrev_t {
44
45
  const char *abbreviated;
  const char *full;
46
  int commandline_only;
47
  int warn;
48
49
} config_abbrev_t;

50
51
/* Handy macro for declaring "In the config file or on the command line,
 * you can abbreviate <b>tok</b>s as <b>tok</b>". */
52
#define PLURAL(tok) { #tok, #tok "s", 0, 0 }
53

Nick Mathewson's avatar
Nick Mathewson committed
54
/* A list of command-line abbreviations. */
55
static config_abbrev_t _option_abbrevs[] = {
56
  PLURAL(ExitNode),
57
  PLURAL(EntryNode),
58
59
  PLURAL(ExcludeNode),
  PLURAL(FirewallPort),
60
  PLURAL(LongLivedPort),
61
62
  PLURAL(HiddenServiceNode),
  PLURAL(HiddenServiceExcludeNode),
63
  PLURAL(NumCpu),
64
65
  PLURAL(RendNode),
  PLURAL(RendExcludeNode),
66
67
  PLURAL(StrictEntryNode),
  PLURAL(StrictExitNode),
68
  { "l", "Log", 1, 0},
69
  { "AllowUnverifiedNodes", "AllowInvalidNodes", 0, 0},
70
71
  { "AutomapHostSuffixes", "AutomapHostsSuffixes", 0, 0},
  { "AutomapHostOnResolve", "AutomapHostsOnResolve", 0, 0},
72
73
74
75
  { "BandwidthRateBytes", "BandwidthRate", 0, 0},
  { "BandwidthBurstBytes", "BandwidthBurst", 0, 0},
  { "DirFetchPostPeriod", "StatusFetchPeriod", 0, 0},
  { "MaxConn", "ConnLimit", 0, 1},
76
77
78
  { "ORBindAddress", "ORListenAddress", 0, 0},
  { "DirBindAddress", "DirListenAddress", 0, 0},
  { "SocksBindAddress", "SocksListenAddress", 0, 0},
79
80
81
82
  { "UseHelperNodes", "UseEntryGuards", 0, 0},
  { "NumHelperNodes", "NumEntryGuards", 0, 0},
  { "UseEntryNodes", "UseEntryGuards", 0, 0},
  { "NumEntryNodes", "NumEntryGuards", 0, 0},
83
84
  { "ResolvConf", "ServerDNSResolvConfFile", 0, 1},
  { "SearchDomains", "ServerDNSSearchDomains", 0, 1},
85
  { "PreferTunnelledDirConns", "PreferTunneledDirConns", 0, 0},
86
  { "BridgeAuthoritativeDirectory", "BridgeAuthoritativeDir", 0, 0},
87
88
89
90
  { NULL, NULL, 0, 0},
};
/* A list of state-file abbreviations, for compatibility. */
static config_abbrev_t _state_abbrevs[] = {
91
  { "AccountingBytesReadInterval", "AccountingBytesReadInInterval", 0, 0 },
92
93
94
95
96
97
  { "HelperNode", "EntryGuard", 0, 0 },
  { "HelperNodeDownSince", "EntryGuardDownSince", 0, 0 },
  { "HelperNodeUnlistedSince", "EntryGuardUnlistedSince", 0, 0 },
  { "EntryNode", "EntryGuard", 0, 0 },
  { "EntryNodeDownSince", "EntryGuardDownSince", 0, 0 },
  { "EntryNodeUnlistedSince", "EntryGuardUnlistedSince", 0, 0 },
98
  { NULL, NULL, 0, 0},
99
};
100
#undef PLURAL
101

102
/** A variable allowed in the configuration file or on the command line. */
103
typedef struct config_var_t {
104
  const char *name; /**< The full keyword (case insensitive). */
105
106
  config_type_t type; /**< How to interpret the type and turn it into a
                       * value. */
107
108
  off_t var_offset; /**< Offset of the corresponding member of or_options_t. */
  const char *initvalue; /**< String (or null) describing initial value. */
109
110
} config_var_t;

Nick Mathewson's avatar
Nick Mathewson committed
111
112
113
114
/** 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>"
 */
115
116
#define VAR(name,conftype,member,initvalue)                             \
  { name, CONFIG_TYPE_ ## conftype, STRUCT_OFFSET(or_options_t, member), \
117
      initvalue }
118
119
120
/** As VAR, but the option name and member name are the same. */
#define V(member,conftype,initvalue)                                    \
  VAR(#member, conftype, member, initvalue)
Nick Mathewson's avatar
Nick Mathewson committed
121
/** An entry for config_vars: "The option <b>name</b> is obsolete." */
122
#define OBSOLETE(name) { name, CONFIG_TYPE_OBSOLETE, 0, NULL }
123

Nick Mathewson's avatar
Nick Mathewson committed
124
125
126
127
/** Array of configuration options.  Until we disallow nonstandard
 * abbreviations, order is significant, since the first matching option will
 * be chosen first.
 */
128
static config_var_t _option_vars[] = {
129
  OBSOLETE("AccountingMaxKB"),
130
131
132
133
134
  V(AccountingMax,               MEMUNIT,  "0 bytes"),
  V(AccountingStart,             STRING,   NULL),
  V(Address,                     STRING,   NULL),
  V(AllowInvalidNodes,           CSV,      "middle,rendezvous"),
  V(AllowNonRFC953Hostnames,     BOOL,     "0"),
135
136
137
  V(AlternateBridgeAuthority,    LINELIST, NULL),
  V(AlternateDirAuthority,       LINELIST, NULL),
  V(AlternateHSAuthority,        LINELIST, NULL),
138
  V(AssumeReachable,             BOOL,     "0"),
139
  V(AuthDirBadDir,               LINELIST, NULL),
140
141
142
143
  V(AuthDirBadExit,              LINELIST, NULL),
  V(AuthDirInvalid,              LINELIST, NULL),
  V(AuthDirReject,               LINELIST, NULL),
  V(AuthDirRejectUnlisted,       BOOL,     "0"),
144
  V(AuthDirListBadDirs,          BOOL,     "0"),
145
  V(AuthDirListBadExits,         BOOL,     "0"),
146
147
  V(AuthDirMaxServersPerAddr,    UINT,     "2"),
  V(AuthDirMaxServersPerAuthAddr,UINT,     "5"),
148
149
150
151
  VAR("AuthoritativeDirectory",  BOOL, AuthoritativeDir,    "0"),
  V(AutomapHostsOnResolve,       BOOL,     "0"),
  V(AutomapHostsSuffixes,        CSV,      ".onion,.exit"),
  V(AvoidDiskWrites,             BOOL,     "0"),
152
153
  V(BandwidthBurst,              MEMUNIT,  "10 MB"),
  V(BandwidthRate,               MEMUNIT,  "5 MB"),
154
155
  V(BridgeAuthoritativeDir,      BOOL,     "0"),
  VAR("Bridge",                  LINELIST, Bridges,    NULL),
156
  V(BridgePassword,              STRING,   NULL),
157
  V(BridgeRecordUsageByCountry,  BOOL,     "1"),
158
  V(BridgeRelay,                 BOOL,     "0"),
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
  V(CircuitBuildTimeout,         INTERVAL, "1 minute"),
  V(CircuitIdleTimeout,          INTERVAL, "1 hour"),
  V(ClientDNSRejectInternalAddresses, BOOL,"1"),
  V(ClientOnly,                  BOOL,     "0"),
  V(ConnLimit,                   UINT,     "1000"),
  V(ConstrainedSockets,          BOOL,     "0"),
  V(ConstrainedSockSize,         MEMUNIT,  "8192"),
  V(ContactInfo,                 STRING,   NULL),
  V(ControlListenAddress,        LINELIST, NULL),
  V(ControlPort,                 UINT,     "0"),
  V(ControlSocket,               LINELIST, NULL),
  V(CookieAuthentication,        BOOL,     "0"),
  V(CookieAuthFileGroupReadable, BOOL,     "0"),
  V(CookieAuthFile,              STRING,   NULL),
  V(DataDirectory,               STRING,   NULL),
174
  OBSOLETE("DebugLogFile"),
175
176
  V(DirAllowPrivateAddresses,    BOOL,     NULL),
  V(DirListenAddress,            LINELIST, NULL),
177
  OBSOLETE("DirFetchPeriod"),
178
179
  V(DirPolicy,                   LINELIST, NULL),
  V(DirPort,                     UINT,     "0"),
180
  OBSOLETE("DirPostPeriod"),
181
182
183
184
185
186
187
188
189
190
  VAR("DirServer",               LINELIST, DirServers, NULL),
  V(DNSPort,                     UINT,     "0"),
  V(DNSListenAddress,            LINELIST, NULL),
  V(DownloadExtraInfo,           BOOL,     "0"),
  V(EnforceDistinctSubnets,      BOOL,     "1"),
  V(EntryNodes,                  STRING,   NULL),
  V(ExcludeNodes,                STRING,   NULL),
  V(ExitNodes,                   STRING,   NULL),
  V(ExitPolicy,                  LINELIST, NULL),
  V(ExitPolicyRejectPrivate,     BOOL,     "1"),
191
  V(FallbackNetworkstatusFile,   STRING,
192
    SHARE_DATADIR PATH_SEPARATOR "tor" PATH_SEPARATOR "fallback-consensus"),
193
194
195
  V(FascistFirewall,             BOOL,     "0"),
  V(FirewallPorts,               CSV,      ""),
  V(FastFirstHopPK,              BOOL,     "1"),
196
  V(FetchDirInfoEarly,           BOOL,     "0"),
197
198
199
  V(FetchServerDescriptors,      BOOL,     "1"),
  V(FetchHidServDescriptors,     BOOL,     "1"),
  V(FetchUselessDescriptors,     BOOL,     "0"),
200
  V(GeoIPFile,                   STRING,   NULL),
201
202
  V(Group,                       STRING,   NULL),
  V(HardwareAccel,               BOOL,     "0"),
203
  V(HashedControlPassword,       LINELIST, NULL),
204
  V(HidServDirectoryV2,          BOOL,     "0"),
Nick Mathewson's avatar
Nick Mathewson committed
205
206
207
208
209
  VAR("HiddenServiceDir",    LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceExcludeNodes", LINELIST_S, RendConfigLines, NULL),
  VAR("HiddenServiceNodes",  LINELIST_S, RendConfigLines,    NULL),
  VAR("HiddenServiceOptions",LINELIST_V, RendConfigLines,    NULL),
  VAR("HiddenServicePort",   LINELIST_S, RendConfigLines,    NULL),
210
  VAR("HiddenServiceVersion",LINELIST_S, RendConfigLines,    NULL),
211
212
213
214
215
216
  V(HSAuthoritativeDir,          BOOL,     "0"),
  V(HSAuthorityRecordStats,      BOOL,     "0"),
  V(HttpProxy,                   STRING,   NULL),
  V(HttpProxyAuthenticator,      STRING,   NULL),
  V(HttpsProxy,                  STRING,   NULL),
  V(HttpsProxyAuthenticator,     STRING,   NULL),
217
  OBSOLETE("IgnoreVersion"),
218
219
  V(KeepalivePeriod,             INTERVAL, "5 minutes"),
  VAR("Log",                     LINELIST, Logs,             NULL),
220
  OBSOLETE("LinkPadding"),
221
222
  OBSOLETE("LogLevel"),
  OBSOLETE("LogFile"),
223
  V(LongLivedPorts,              CSV,
224
                         "21,22,706,1863,5050,5190,5222,5223,6667,6697,8300"),
225
226
227
228
  VAR("MapAddress",              LINELIST, AddressMap,           NULL),
  V(MaxAdvertisedBandwidth,      MEMUNIT,  "1 GB"),
  V(MaxCircuitDirtiness,         INTERVAL, "10 minutes"),
  V(MaxOnionsPending,            UINT,     "100"),
229
  OBSOLETE("MonthlyAccountingStart"),
230
231
  V(MyFamily,                    STRING,   NULL),
  V(NewCircuitPeriod,            INTERVAL, "30 seconds"),
232
  VAR("NamingAuthoritativeDirectory",BOOL, NamingAuthoritativeDir, "0"),
233
234
235
236
237
238
239
240
241
242
  V(NatdListenAddress,           LINELIST, NULL),
  V(NatdPort,                    UINT,     "0"),
  V(Nickname,                    STRING,   NULL),
  V(NoPublish,                   BOOL,     "0"),
  VAR("NodeFamily",              LINELIST, NodeFamilies,         NULL),
  V(NumCpus,                     UINT,     "1"),
  V(NumEntryGuards,              UINT,     "3"),
  V(ORListenAddress,             LINELIST, NULL),
  V(ORPort,                      UINT,     "0"),
  V(OutboundBindAddress,         STRING,   NULL),
243
  OBSOLETE("PathlenCoinWeight"),
244
245
246
  V(PidFile,                     STRING,   NULL),
  V(PreferTunneledDirConns,      BOOL,     "0"),
  V(ProtocolWarnings,            BOOL,     "0"),
247
  V(PublishServerDescriptor,     CSV,      "1"),
248
249
250
251
252
253
254
255
  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(RedirectExit,                LINELIST, NULL),
256
  V(RejectPlaintextPorts,        CSV,      ""),
257
258
259
260
261
262
  V(RelayBandwidthBurst,         MEMUNIT,  "0"),
  V(RelayBandwidthRate,          MEMUNIT,  "0"),
  V(RendExcludeNodes,            STRING,   NULL),
  V(RendNodes,                   STRING,   NULL),
  V(RendPostPeriod,              INTERVAL, "1 hour"),
  V(RephistTrackTime,            INTERVAL, "24 hours"),
263
  OBSOLETE("RouterFile"),
264
265
266
267
  V(RunAsDaemon,                 BOOL,     "0"),
  V(RunTesting,                  BOOL,     "0"),
  V(SafeLogging,                 BOOL,     "1"),
  V(SafeSocks,                   BOOL,     "0"),
268
  V(ServerDNSAllowBrokenResolvConf, BOOL,  "0"),
269
270
271
272
273
  V(ServerDNSAllowNonRFC953Hostnames, BOOL,"0"),
  V(ServerDNSDetectHijacking,    BOOL,     "1"),
  V(ServerDNSResolvConfFile,     STRING,   NULL),
  V(ServerDNSSearchDomains,      BOOL,     "0"),
  V(ServerDNSTestAddresses,      CSV,
274
      "www.google.com,www.mit.edu,www.yahoo.com,www.slashdot.org"),
275
276
277
278
279
  V(ShutdownWaitLength,          INTERVAL, "30 seconds"),
  V(SocksListenAddress,          LINELIST, NULL),
  V(SocksPolicy,                 LINELIST, NULL),
  V(SocksPort,                   UINT,     "9050"),
  V(SocksTimeout,                INTERVAL, "2 minutes"),
280
  OBSOLETE("StatusFetchPeriod"),
281
282
  V(StrictEntryNodes,            BOOL,     "0"),
  V(StrictExitNodes,             BOOL,     "0"),
283
  OBSOLETE("SysLog"),
284
285
286
287
  V(TestSocks,                   BOOL,     "0"),
  V(TestVia,                     STRING,   NULL),
  V(TrackHostExits,              CSV,      NULL),
  V(TrackHostExitsExpire,        INTERVAL, "30 minutes"),
288
  OBSOLETE("TrafficShaping"),
289
290
291
292
293
294
295
  V(TransListenAddress,          LINELIST, NULL),
  V(TransPort,                   UINT,     "0"),
  V(TunnelDirConns,              BOOL,     "0"),
  V(UpdateBridgesFromAuthority,  BOOL,     "0"),
  V(UseBridges,                  BOOL,     "0"),
  V(UseEntryGuards,              BOOL,     "1"),
  V(User,                        STRING,   NULL),
296
  VAR("V1AuthoritativeDirectory",BOOL, V1AuthoritativeDir,   "0"),
297
  VAR("V2AuthoritativeDirectory",BOOL, V2AuthoritativeDir,   "0"),
298
  VAR("V3AuthoritativeDirectory",BOOL, V3AuthoritativeDir,   "0"),
299
300
301
302
  V(V3AuthVotingInterval,        INTERVAL, "1 hour"),
  V(V3AuthVoteDelay,             INTERVAL, "5 minutes"),
  V(V3AuthDistDelay,             INTERVAL, "5 minutes"),
  V(V3AuthNIntervalsValid,       UINT,     "3"),
303
  VAR("VersioningAuthoritativeDirectory",BOOL,VersioningAuthoritativeDir, "0"),
304
  V(VirtualAddrNetwork,          STRING,   "127.192.0.0/10"),
305
  V(WarnPlaintextPorts,          CSV,      "23,109,110,143"),
306
307
308
  VAR("__AllDirActionsPrivate",  BOOL,  AllDirActionsPrivate,     "0"),
  VAR("__DisablePredictedCircuits",BOOL,DisablePredictedCircuits, "0"),
  VAR("__LeaveStreamsUnattached",BOOL,  LeaveStreamsUnattached,   "0"),
309
310
  VAR("__HashedControlSessionPassword", LINELIST, HashedControlSessionPassword,
      NULL),
311
  V(MinUptimeHidServDirectoryV2, INTERVAL, "24 hours"),
312
  { NULL, CONFIG_TYPE_OBSOLETE, 0, NULL }
313
};
314
315
#undef VAR

316
317
#define VAR(name,conftype,member,initvalue)                             \
  { name, CONFIG_TYPE_ ## conftype, STRUCT_OFFSET(or_state_t, member),  \
318
      initvalue }
319
static config_var_t _state_vars[] = {
320
321
322
323
324
  V(AccountingBytesReadInInterval,    MEMUNIT,  NULL),
  V(AccountingBytesWrittenInInterval, MEMUNIT,  NULL),
  V(AccountingExpectedUsage,          MEMUNIT,  NULL),
  V(AccountingIntervalStart,          ISOTIME,  NULL),
  V(AccountingSecondsActive,          INTERVAL, NULL),
Roger Dingledine's avatar
Roger Dingledine committed
325

326
327
328
  VAR("EntryGuard",              LINELIST_S,  EntryGuards,             NULL),
  VAR("EntryGuardDownSince",     LINELIST_S,  EntryGuards,             NULL),
  VAR("EntryGuardUnlistedSince", LINELIST_S,  EntryGuards,             NULL),
329
  VAR("EntryGuardAddedBy",       LINELIST_S,  EntryGuards,             NULL),
330
  V(EntryGuards,                 LINELIST_V,  NULL),
Nick Mathewson's avatar
Nick Mathewson committed
331

332
333
334
335
336
337
  V(BWHistoryReadEnds,                ISOTIME,  NULL),
  V(BWHistoryReadInterval,            UINT,     "900"),
  V(BWHistoryReadValues,              CSV,      ""),
  V(BWHistoryWriteEnds,               ISOTIME,  NULL),
  V(BWHistoryWriteInterval,           UINT,     "900"),
  V(BWHistoryWriteValues,             CSV,      ""),
338

339
  V(TorVersion,                       STRING,   NULL),
340

341
342
  V(LastRotatedOnionKey,              ISOTIME,  NULL),
  V(LastWritten,                      ISOTIME,  NULL),
343

344
  { NULL, CONFIG_TYPE_OBSOLETE, 0, NULL }
345
346
};

347
#undef VAR
348
#undef V
349
350
#undef OBSOLETE

351
352
/** Represents an English description of a configuration variable; used when
 * generating configuration file comments. */
353
354
355
356
357
358
typedef struct config_var_description_t {
  const char *name;
  const char *description;
} config_var_description_t;

static config_var_description_t options_description[] = {
359
  /* ==== general options */
360
361
  { "AvoidDiskWrites", "If non-zero, try to write to disk less frequently than"
    " we would otherwise." },
362
363
364
365
  { "BandwidthRate", "A token bucket limits the average incoming bandwidth on "
    "this node to the specified number of bytes per second." },
  { "BandwidthBurst", "Limit the maximum token buffer size (also known as "
    "burst) to the given number of bytes." },
366
  { "ConnLimit", "Minimum number of simultaneous sockets we must have." },
367
368
369
370
371
  { "ConstrainedSockets", "Shrink tx and rx buffers for sockets to avoid "
    "system limits on vservers and related environments.  See man page for "
    "more information regarding this option." },
  { "ConstrainedSockSize", "Limit socket buffers to this size when "
    "ConstrainedSockets is enabled." },
372
373
374
375
376
377
378
  /*  ControlListenAddress */
  { "ControlPort", "If set, Tor will accept connections from the same machine "
    "(localhost only) on this port, and allow those connections to control "
    "the Tor process using the Tor Control Protocol (described in"
    "control-spec.txt).", },
  { "CookieAuthentication", "If this option is set to 1, don't allow any "
    "connections to the control port except when the connecting process "
379
    "can read a file that Tor creates in its data directory." },
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
  { "DataDirectory", "Store working data, state, keys, and caches here." },
  { "DirServer", "Tor only trusts directories signed with one of these "
    "servers' keys.  Used to override the standard list of directory "
    "authorities." },
  /* { "FastFirstHopPK", "" }, */
  /* FetchServerDescriptors, FetchHidServDescriptors,
   * FetchUselessDescriptors */
  { "Group", "On startup, setgid to this group." },
  { "HardwareAccel", "If set, Tor tries to use hardware crypto accelerators "
    "when it can." },
  /* HashedControlPassword */
  { "HTTPProxy", "Force Tor to make all HTTP directory requests through this "
    "host:port (or host:80 if port is not set)." },
  { "HTTPProxyAuthenticator", "A username:password pair to be used with "
    "HTTPProxy." },
  { "HTTPSProxy", "Force Tor to make all TLS (SSL) connectinos through this "
    "host:port (or host:80 if port is not set)." },
  { "HTTPSProxyAuthenticator", "A username:password pair to be used with "
    "HTTPSProxy." },
  { "KeepalivePeriod", "Send a padding cell every N seconds to keep firewalls "
    "from closing our connections while Tor is not in use." },
  { "Log", "Where to send logging messages.  Format is "
    "minSeverity[-maxSeverity] (stderr|stdout|syslog|file FILENAME)." },
  { "OutboundBindAddress", "Make all outbound connections originate from the "
404
    "provided IP address (only useful for multiple network interfaces)." },
405
406
  { "PIDFile", "On startup, write our PID to this file. On clean shutdown, "
    "remove the file." },
407
  { "PreferTunneledDirConns", "If non-zero, avoid directory servers that "
408
    "don't support tunneled connections." },
409
  /* PreferTunneledDirConns */
410
411
412
413
414
415
  /* ProtocolWarnings */
  /* RephistTrackTime */
  { "RunAsDaemon", "If set, Tor forks and daemonizes to the background when "
    "started.  Unix only." },
  { "SafeLogging", "If set to 0, Tor logs potentially sensitive strings "
    "rather than replacing them with the string [scrubbed]." },
416
417
418
  { "TunnelDirConns", "If non-zero, when a directory server we contact "
    "supports it, we will build a one-hop circuit and make an encrypted "
    "connection via its ORPort." },
419
420
421
422
423
  { "User", "On startup, setuid to this user" },

  /* ==== client options */
  { "AllowInvalidNodes", "Where on our circuits should Tor allow servers "
    "that the directory authorities haven't called \"valid\"?" },
424
425
  { "AllowNonRFC953Hostnames", "If set to 1, we don't automatically reject "
    "hostnames for having invalid characters." },
426
427
  /*  CircuitBuildTimeout, CircuitIdleTimeout */
  { "ClientOnly", "If set to 1, Tor will under no circumstances run as a "
428
    "server, even if ORPort is enabled." },
429
  { "EntryNodes", "A list of preferred entry nodes to use for the first hop "
430
    "in circuits, when possible." },
431
432
433
434
435
  /* { "EnforceDistinctSubnets" , "" }, */
  { "ExitNodes", "A list of preferred nodes to use for the last hop in "
    "circuits, when possible." },
  { "ExcludeNodes", "A list of nodes never to use when building a circuit." },
  { "FascistFirewall", "If set, Tor will only create outgoing connections to "
436
437
    "servers running on the ports listed in FirewallPorts." },
  { "FirewallPorts", "A list of ports that we can connect to.  Only used "
438
439
    "when FascistFirewall is set." },
  { "LongLivedPorts", "A list of ports for services that tend to require "
440
    "high-uptime connections." },
441
442
443
  { "MapAddress", "Force Tor to treat all requests for one address as if "
    "they were for another." },
  { "NewCircuitPeriod", "Force Tor to consider whether to build a new circuit "
444
    "every NUM seconds." },
445
  { "MaxCircuitDirtiness", "Do not attach new streams to a circuit that has "
446
    "been used more than this many seconds ago." },
447
448
449
450
451
452
453
454
455
  /* NatdPort, NatdListenAddress */
  { "NodeFamily", "A list of servers that constitute a 'family' and should "
    "never be used in the same circuit." },
  { "NumEntryGuards", "How many entry guards should we keep at a time?" },
  /* PathlenCoinWeight */
  { "ReachableAddresses", "Addresses we can connect to, as IP/bits:port-port. "
    "By default, we assume all addresses are reachable." },
  /* reachablediraddresses, reachableoraddresses. */
  { "RendNodes", "A list of preferred nodes to use for a rendezvous point, "
456
    "when possible." },
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
  { "RendExcludenodes", "A list of nodes never to use as rendezvous points." },
  /* SafeSOCKS */
  { "SOCKSPort", "The port where we listen for SOCKS connections from "
    "applications." },
  { "SOCKSListenAddress", "Bind to this address to listen to connections from "
    "SOCKS-speaking applications." },
  { "SOCKSPolicy", "Set an entry policy to limit which addresses can connect "
    "to the SOCKSPort." },
  /* SocksTimeout */
  { "StrictExitNodes", "If set, Tor will fail to operate when none of the "
    "configured ExitNodes can be used." },
  { "StrictEntryNodes", "If set, Tor will fail to operate when none of the "
    "configured EntryNodes can be used." },
  /* TestSocks */
  { "TrackHostsExit", "Hosts and domains which should, if possible, be "
472
    "accessed from the same exit node each time we connect to them." },
473
474
475
476
  { "TrackHostsExitExpire", "Time after which we forget which exit we were "
    "using to connect to hosts in TrackHostsExit." },
  /* "TransPort", "TransListenAddress */
  { "UseEntryGuards", "Set to 0 if we want to pick from the whole set of "
477
478
    "servers for the first position in each circuit, rather than picking a "
    "set of 'Guards' to prevent profiling attacks." },
479
480

  /* === server options */
481
  { "Address", "The advertised (external) address we should use." },
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
  /* Accounting* options. */
  /* AssumeReachable */
  { "ContactInfo", "Administrative contact information to advertise for this "
    "server." },
  { "ExitPolicy", "Address/port ranges for which to accept or reject outgoing "
    "connections on behalf of Tor users." },
  /*  { "ExitPolicyRejectPrivate, "" }, */
  { "MaxAdvertisedBandwidth", "If set, we will not advertise more than this "
    "amount of bandwidth for our bandwidth rate, regardless of how much "
    "bandwidth we actually detect." },
  { "MaxOnionsPending", "Reject new attempts to extend circuits when we "
    "already have this many pending." },
  { "MyFamily", "Declare a list of other servers as belonging to the same "
    "family as this one, so that clients will not use two from the same "
    "family in the same circuit." },
  { "Nickname", "Set the server nickname." },
498
  { "NoPublish", "{DEPRECATED}" },
499
500
501
502
503
  { "NumCPUs", "How many processes to use at once for public-key crypto." },
  { "ORPort", "Advertise this port to listen for connections from Tor clients "
    "and servers." },
  { "ORListenAddress", "Bind to this address to listen for connections from "
    "clients and servers, instead of the default 0.0.0.0:ORPort." },
504
  { "PublishServerDescriptor", "Set to 0 to keep the server from "
505
    "uploading info to the directory authorities." },
506
507
508
509
510
511
512
513
  /*{ "RedirectExit", "When an outgoing connection tries to connect to a "
   *"given address, redirect it to another address instead." },
   */
  /* ServerDNS: DetectHijacking, ResolvConfFile, SearchDomains */
  { "ShutdownWaitLength", "Wait this long for clients to finish when "
    "shutting down because of a SIGINT." },
  /* { "TestVia", } */

514
  /* === directory cache options */
515
516
  { "DirPort", "Serve directory information from this port, and act as a "
    "directory cache." },
517
  { "DirListenAddress", "Bind to this address to listen for connections from "
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
    "clients and servers, instead of the default 0.0.0.0:DirPort." },
  { "DirPolicy", "Set a policy to limit who can connect to the directory "
    "port" },

  /*  Authority options: AuthDirBadExit, AuthDirInvalid, AuthDirReject,
   * AuthDirRejectUnlisted, AuthDirListBadExits, AuthoritativeDirectory,
   * DirAllowPrivateAddresses, HSAuthoritativeDir,
   * NamingAuthoritativeDirectory, RecommendedVersions,
   * RecommendedClientVersions, RecommendedServerVersions, RendPostPeriod,
   * RunTesting, V1AuthoritativeDirectory, VersioningAuthoritativeDirectory, */

  /* Hidden service options: HiddenService: dir,excludenodes, nodes,
   * options, port.  PublishHidServDescriptor */

  /* Nonpersistent options: __LeaveStreamsUnattached, __AllDirActionsPrivate */
533
534
535
536
  { NULL, NULL },
};

static config_var_description_t state_description[] = {
537
  { "AccountingBytesReadInInterval",
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
    "How many bytes have we read in this accounting period?" },
  { "AccountingBytesWrittenInInterval",
    "How many bytes have we written in this accounting period?" },
  { "AccountingExpectedUsage",
    "How many bytes did we expect to use per minute? (0 for no estimate.)" },
  { "AccountingIntervalStart", "When did this accounting period begin?" },
  { "AccountingSecondsActive", "How long have we been awake in this period?" },

  { "BWHistoryReadEnds", "When does the last-recorded read-interval end?" },
  { "BWHistoryReadInterval", "How long is each read-interval (in seconds)?" },
  { "BWHistoryReadValues", "Number of bytes read in each interval." },
  { "BWHistoryWriteEnds", "When does the last-recorded write-interval end?" },
  { "BWHistoryWriteInterval", "How long is each write-interval (in seconds)?"},
  { "BWHistoryWriteValues", "Number of bytes written in each interval." },

553
554
  { "EntryGuard", "One of the nodes we have chosen as a fixed entry" },
  { "EntryGuardDownSince",
555
    "The last entry guard has been unreachable since this time." },
556
  { "EntryGuardUnlistedSince",
557
    "The last entry guard has been unusable since this time." },
Roger Dingledine's avatar
Roger Dingledine committed
558

559
560
561
  { "LastRotatedOnionKey",
    "The last time at which we changed the medium-term private key used for "
    "building circuits." },
562
563
564
  { "LastWritten", "When was this state file last regenerated?" },

  { "TorVersion", "Which version of Tor generated this state file?" },
565
566
567
  { NULL, NULL },
};

568
/** Type of a callback to validate whether a given configuration is
Roger Dingledine's avatar
Roger Dingledine committed
569
 * well-formed and consistent. See options_trial_assign() for documentation
570
 * of arguments. */
571
typedef int (*validate_fn_t)(void*,void*,int,char**);
572

573
574
575
/** Information on the keys, value types, key-to-struct-member mappings,
 * variable descriptions, validation functions, and abbreviations for a
 * configuration or storage format. */
576
typedef struct {
577
578
579
  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. */
Roger Dingledine's avatar
Roger Dingledine committed
580
  off_t magic_offset; /**< Offset of the magic value within the struct. */
581
  config_abbrev_t *abbrevs; /**< List of abbreviations that we expand when
Roger Dingledine's avatar
Roger Dingledine committed
582
                             * parsing this format. */
583
584
585
586
  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. */
  /** Documentation for configuration variables. */
587
  config_var_description_t *descriptions;
Roger Dingledine's avatar
Roger Dingledine committed
588
589
590
  /** If present, extra is a LINELIST variable for unrecognized
   * lines.  Otherwise, unrecognized lines are an error. */
  config_var_t *extra;
591
592
} config_format_t;

593
594
/** Macro: assert that <b>cfg</b> has the right magic field for format
 * <b>fmt</b>. */
595
#define CHECK(fmt, cfg) STMT_BEGIN                                      \
596
    tor_assert(fmt && cfg);                                             \
597
    tor_assert((fmt)->magic ==                                          \
598
               *(uint32_t*)STRUCT_VAR_P(cfg,fmt->magic_offset));        \
599
  STMT_END
600

601
static void config_line_append(config_line_t **lst,
602
                               const char *key, const char *val);
603
604
static void option_clear(config_format_t *fmt, or_options_t *options,
                         config_var_t *var);
605
static void option_reset(config_format_t *fmt, or_options_t *options,
606
                         config_var_t *var, int use_defaults);
607
static void config_free(config_format_t *fmt, void *options);
608
static int config_lines_eq(config_line_t *a, config_line_t *b);
609
static int option_is_same(config_format_t *fmt,
610
611
                          or_options_t *o1, or_options_t *o2,
                          const char *name);
612
static or_options_t *options_dup(config_format_t *fmt, or_options_t *old);
613
614
615
static int options_validate(or_options_t *old_options, or_options_t *options,
                            int from_setconf, char **msg);
static int options_act_reversible(or_options_t *old_options, char **msg);
616
static int options_act(or_options_t *old_options);
617
618
static int options_transition_allowed(or_options_t *old, or_options_t *new,
                                      char **msg);
619
620
621
622
static int options_transition_affects_workers(or_options_t *old_options,
                                              or_options_t *new_options);
static int options_transition_affects_descriptor(or_options_t *old_options,
                                                 or_options_t *new_options);
623
static int check_nickname_list(const char *lst, const char *name, char **msg);
624
static void config_register_addressmaps(or_options_t *options);
625

626
static int parse_bridge_line(const char *line, int validate_only);
627
628
629
static int parse_dir_server_line(const char *line,
                                 authority_type_t required_type,
                                 int validate_only);
630
static int parse_redirect_line(smartlist_t *result,
631
                               config_line_t *line, char **msg);
632
633
static int parse_log_severity_range(const char *range, int *min_out,
                                    int *max_out);
634
static int validate_data_directory(or_options_t *options);
635
static int write_configuration_file(const char *fname, or_options_t *options);
636
static config_line_t *get_assigned_option(config_format_t *fmt,
637
638
                                      or_options_t *options, const char *key,
                                      int escape_val);
639
static void config_init(config_format_t *fmt, void *options);
640
static int or_state_validate(or_state_t *old_options, or_state_t *options,
641
                             int from_setconf, char **msg);
642
643
static int or_state_load(void);
static int options_init_logs(or_options_t *options, int validate_only);
644

645
646
static uint64_t config_parse_memunit(const char *s, int *ok);
static int config_parse_interval(const char *s, int *ok);
647
static void print_svn_version(void);
648
static void init_libevent(void);
649
static int opt_streq(const char *s1, const char *s2);
650
/** Versions of libevent. */
651
typedef enum {
652
653
  /* Note: we compare these, so it's important that "old" precede everything,
   * and that "other" come last. */
654
  LE_OLD=0, LE_10C, LE_10D, LE_10E, LE_11, LE_11A, LE_11B, LE_12, LE_12A,
655
  LE_13, LE_13A, LE_13B, LE_13C, LE_13D,
656
  LE_OTHER
657
658
} le_version_t;
static le_version_t decode_libevent_version(void);
659
#if defined(HAVE_EVENT_GET_VERSION) && defined(HAVE_EVENT_GET_METHOD)
660
static void check_libevent_version(const char *m, int server);
661
#endif
662

663
/** Magic value for or_options_t. */
664
665
#define OR_OPTIONS_MAGIC 9090909

666
/** Configuration format for or_options_t. */
667
static config_format_t options_format = {
668
669
670
  sizeof(or_options_t),
  OR_OPTIONS_MAGIC,
  STRUCT_OFFSET(or_options_t, _magic),
671
672
673
  _option_abbrevs,
  _option_vars,
  (validate_fn_t)options_validate,
674
675
  options_description,
  NULL
676
677
};

678
/** Magic value for or_state_t. */
679
680
#define OR_STATE_MAGIC 0x57A73f57

681
682
/** "Extra" variable in the state that receives lines we can't parse. This
 * lets us preserve options from versions of Tor newer than us. */
683
684
685
686
static config_var_t state_extra_var = {
  "__extra", CONFIG_TYPE_LINELIST, STRUCT_OFFSET(or_state_t, ExtraLines), NULL
};

687
/** Configuration format for or_state_t. */
688
689
690
691
static config_format_t state_format = {
  sizeof(or_state_t),
  OR_STATE_MAGIC,
  STRUCT_OFFSET(or_state_t, _magic),
692
  _state_abbrevs,
693
694
  _state_vars,
  (validate_fn_t)or_state_validate,
695
696
  state_description,
  &state_extra_var,
697
698
};

699
700
701
702
703
/*
 * Functions to read and write the global options pointer.
 */

/** Command-line and config-file options. */
704
static or_options_t *global_options = NULL;
Roger Dingledine's avatar
Roger Dingledine committed
705
/** Name of most recently read torrc file. */
706
static char *torrc_fname = NULL;
707
/** Persistent serialized state. */
708
static or_state_t *global_state = NULL;
709

710
/** Allocate an empty configuration object of a given format type. */
711
712
713
static void *
config_alloc(config_format_t *fmt)
{
714
  void *opts = tor_malloc_zero(fmt->size);
715
  *(uint32_t*)STRUCT_VAR_P(opts, fmt->magic_offset) = fmt->magic;
716
717
718
719
  CHECK(fmt, opts);
  return opts;
}

720
721
/** Return the currently configured options. */
or_options_t *
722
723
get_options(void)
{
724
725
726
  tor_assert(global_options);
  return global_options;
}
727

728
729
730
/** 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.
731
 */
732
int
733
set_options(or_options_t *new_val, char **msg)
734
{
735
  or_options_t *old_options = global_options;
736
  global_options = new_val;
737
738
  /* Note that we pass the *old* options below, for comparison. It
   * pulls the new options directly out of global_options. */
739
740
  if (options_act_reversible(old_options, msg)<0) {
    tor_assert(*msg);
741
742
743
    global_options = old_options;
    return -1;
  }
744
  if (options_act(old_options) < 0) { /* acting on the options failed. die. */
745
    log_err(LD_BUG,
Roger Dingledine's avatar
Roger Dingledine committed
746
            "Acting on config options left us in a broken state. Dying.");
747
748
749
    exit(1);
  }
  if (old_options)
750
    config_free(&options_format, old_options);
751
752

  return 0;
753
754
}

Roger Dingledine's avatar
Roger Dingledine committed
755
extern const char tor_svn_revision[]; /* from tor_main.c */
756

757
758
static char *_version = NULL;

759
760
761
762
/** Return the current Tor version, possibly */
const char *
get_version(void)
{
763
  if (_version == NULL) {
764
765
    if (strlen(tor_svn_revision)) {
      size_t len = strlen(VERSION)+strlen(tor_svn_revision)+8;
766
767
      _version = tor_malloc(len);
      tor_snprintf(_version, len, "%s (r%s)", VERSION, tor_svn_revision);
768
    } else {
769
      _version = tor_strdup(VERSION);
770
771
    }
  }
772
  return _version;
773
774
}

775
776
/** Release all memory and resources held by global configuration structures.
 */
777
778
779
void
config_free_all(void)
{
780
781
782
783
784
785
786
787
  if (global_options) {
    config_free(&options_format, global_options);
    global_options = NULL;
  }
  if (global_state) {
    config_free(&state_format, global_state);
    global_state = NULL;
  }
788
  tor_free(torrc_fname);
789
  tor_free(_version);
790
791
}

792
793
794
795
/** If options->SafeLogging is on, return a not very useful string,
 * else return address.
 */
const char *
796
797
safe_str(const char *address)
{
798
  tor_assert(address);
799
800
801
802
803
804
  if (get_options()->SafeLogging)
    return "[scrubbed]";
  else
    return address;
}

805
/** Equivalent to escaped(safe_str(address)).  See reentrancy note on
806
807
 * escaped(): don't use this outside the main thread, or twice in the same
 * log statement. */
808
809
810
811
812
813
814
815
816
const char *
escaped_safe_str(const char *address)
{
  if (get_options()->SafeLogging)
    return "[scrubbed]";
  else
    return escaped(address);
}

817
818
/** Add the default directory authorities directly into the trusted dir list,
 * but only add them insofar as they share bits with <b>type</b>. */
819
static void
820
add_default_trusted_dir_authorities(authority_type_t type)
821
{
822
  int i;
823
  const char *dirservers[] = {
824
825
    "moria1 v1 orport=9001 v3ident=5420FD8EA46BD4290F1D07A1883C9D85ECC486C4 "
      "128.31.0.34:9031 FFCB 46DB 1339 DA84 674C 70D7 CB58 6434 C437 0441",
826
    "moria2 v1 orport=9002 128.31.0.34:9032 "
827
      "719B E45D E224 B607 C537 07D0 E214 3E2D 423E 74CF",
Peter Palfrader's avatar
Peter Palfrader committed
828
829
    "tor26 v1 orport=443 v3ident=A9AC67E64B200BBF2FA26DF194AC0469E2A948C6 "
      "86.59.21.38:80 847B 1F85 0344 D787 6491 A548 92F9 0493 4E4E B85D",
830
831
    "lefkada orport=443 v3ident=0D95B91896E6089AB9A3C6CB56E724CAF898C43F "
      "140.247.60.64:80 38D4 F5FC F7B1 0232 28B8 95EA 56ED E7D5 CCDC AF32",
832
833
    "dizum 194.109.206.212:80 "
      "7EA6 EAD6 FD83 083C 538F 4403 8BBF A077 587D D755",
834
835
    "Tonga orport=443 bridge no-v2 82.94.251.206:80 "
      "4A0C CD2D DC79 9508 3D73 F5D6 6710 0C8A 5831 F16D",
836
837
    "ides orport=9090 no-v2 v3ident=27B6B5996C426270A5C95488AA5BCEB6BCC86956 "
      "216.224.124.114:9030 F397 038A DC51 3361 35E7 B80B D99C A384 4360 292B",
838
839
840
    "gabelmoo orport=443 no-v2 "
      "v3ident=EAA879B5C75032E462CB018630D2D0DF46EBA606 "
      "88.198.7.215:80 6833 3D07 61BC F397 A587 A0C0 B963 E4A9 E99E C4D3",
841
842
843
    "dannenberg orport=443 no-v2 "
      "v3ident=585769C78764D58426B8B52B6651A5A71137189A "
      "213.73.91.31:80 7BE6 83E6 5D48 1413 21C5 ED92 F075 C553 64AC 7123",
844
    NULL
845
  };
846
847
848
849
850
851
  for (i=0; dirservers[i]; i++) {
    if (parse_dir_server_line(dirservers[i], type, 0)<0) {
      log_err(LD_BUG, "Couldn't parse internal dirserver line %s",
              dirservers[i]);
    }
  }
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
}

/** Look at all the config options for using alternate directory
 * authorities, and make sure none of them are broken. Also, warn the
 * user if we changed any dangerous ones.
 */
static int
validate_dir_authorities(or_options_t *options, or_options_t *old_options)
{
  config_line_t *cl;

  if (options->DirServers &&
      (options->AlternateDirAuthority || options->AlternateBridgeAuthority ||
       options->AlternateHSAuthority)) {
    log_warn(LD_CONFIG,
             "You cannot set both DirServers and Alternate*Authority.");
    return -1;
  }

  /* do we want to complain to the user about being partitionable? */
  if ((options->DirServers &&
       (!old_options ||
        !config_lines_eq(options->DirServers, old_options->DirServers))) ||
      (options->AlternateDirAuthority &&
       (!old_options ||
        !config_lines_eq(options->AlternateDirAuthority,
                         old_options->AlternateDirAuthority)))) {
    log_warn(LD_CONFIG,
             "You have used DirServer or AlternateDirAuthority to "
             "specify alternate directory authorities in "
             "your configuration. This is potentially dangerous: it can "
             "make you look different from all other Tor users, and hurt "
             "your anonymity. Even if you've specified the same "
             "authorities as Tor uses by default, the defaults could "
             "change in the future. Be sure you know what you're doing.");
  }

  /* Now go through the four ways you can configure an alternate
   * set of directory authorities, and make sure none are broken. */
  for (cl = options->DirServers; cl; cl = cl->next)
892
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 1)<0)
893
894
      return -1;
  for (cl = options->AlternateBridgeAuthority; cl; cl = cl->next)
895
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 1)<0)
896
897
      return -1;
  for (cl = options->AlternateDirAuthority; cl; cl = cl->next)
898
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 1)<0)
899
900
      return -1;
  for (cl = options->AlternateHSAuthority; cl; cl = cl->next)
901
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 1)<0)
902
903
904
905
906
907
908
909
910
911
912
913
914
      return -1;
  return 0;
}

/** Look at all the config options and assign new dir authorities
 * as appropriate.
 */
static int
consider_adding_dir_authorities(or_options_t *options,
                                or_options_t *old_options)
{
  config_line_t *cl;
  int need_to_update =
915
    !smartlist_len(router_get_trusted_dir_servers()) || !old_options ||
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
    !config_lines_eq(options->DirServers, old_options->DirServers) ||
    !config_lines_eq(options->AlternateBridgeAuthority,
                     old_options->AlternateBridgeAuthority) ||
    !config_lines_eq(options->AlternateDirAuthority,
                     old_options->AlternateDirAuthority) ||
    !config_lines_eq(options->AlternateHSAuthority,
                     old_options->AlternateHSAuthority);

  if (!need_to_update)
    return 0; /* all done */

  /* Start from a clean slate. */
  clear_trusted_dir_servers();

  if (!options->DirServers) {
    /* then we may want some of the defaults */
    authority_type_t type = NO_AUTHORITY;
    if (!options->AlternateBridgeAuthority)
      type |= BRIDGE_AUTHORITY;
    if (!options->AlternateDirAuthority)
936
      type |= V1_AUTHORITY | V2_AUTHORITY | V3_AUTHORITY;
937
938
939
940
941
942
    if (!options->AlternateHSAuthority)
      type |= HIDSERV_AUTHORITY;
    add_default_trusted_dir_authorities(type);
  }

  for (cl = options->DirServers; cl; cl = cl->next)
943
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 0)<0)
944
945
      return -1;
  for (cl = options->AlternateBridgeAuthority; cl; cl = cl->next)
946
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 0)<0)
947
948
      return -1;
  for (cl = options->AlternateDirAuthority; cl; cl = cl->next)
949
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 0)<0)
950
951
      return -1;
  for (cl = options->AlternateHSAuthority; cl; cl = cl->next)
952
    if (parse_dir_server_line(cl->value, NO_AUTHORITY, 0)<0)
953
954
      return -1;
  return 0;
955
956
}

957
958
959
960
961
962
963
/** Fetch the active option list, and take actions based on it. All of the
 * things we do should survive being done repeatedly.  If present,
 * <b>old_options</b> contains the previous value of the options.
 *
 * Return 0 if all goes well, return -1 if things went badly.
 */
static int
964
options_act_reversible(or_options_t *old_options, char **msg)
965
966
967
968
969
970
971
972
{
  smartlist_t *new_listeners = smartlist_create();
  smartlist_t *replaced_listeners = smartlist_create();
  static int libevent_initialized = 0;
  or_options_t *options = get_options();
  int running_tor = options->command == CMD_RUN_TOR;
  int set_conn_limit = 0;
  int r = -1;
973
  int logs_marked = 0;
974

975
  /* Daemonize _first_, since we only want to open most of this stuff in
976
977
   * the subprocess.  Libevent bases can't be reliably inherited across
   * processes. */
978
979
980
981
982
  if (running_tor && options->RunAsDaemon) {
    /* No need to roll back, since you can't change the value. */
    start_daemon();
  }

983
984
985
986
987
988
989
990
#ifndef HAVE_SYS_UN_H
  if (options->ControlSocket) {
    *msg = tor_strdup("Unix domain sockets (ControlSocket) not supported"
                      " on this OS/with this build.");
    goto rollback;
  }
#endif

991
992
  if (running_tor) {
    /* We need to set the connection limit before we can open the listeners. */
993