From 5a46074e550229e6c19eac9625b26af346b487fc Mon Sep 17 00:00:00 2001 From: Sebastian Hahn Date: Fri, 3 Nov 2017 23:00:27 +0100 Subject: [PATCH 1/4] Revert "Make ClientDNSRejectInternalAddresses testing-only." This reverts commit 27fa4a98d23972213122fa99499efa4baebe49e3. --- doc/tor.1.txt | 15 +++++++-------- src/or/config.c | 16 ++++++++++------ src/or/connection_edge.c | 2 +- src/or/or.h | 2 +- src/or/relay.c | 6 +++--- src/test/test_relaycell.c | 4 ++-- 6 files changed, 24 insertions(+), 21 deletions(-) diff --git a/doc/tor.1.txt b/doc/tor.1.txt index 86999667a5..d701288af7 100644 --- a/doc/tor.1.txt +++ b/doc/tor.1.txt @@ -1440,6 +1440,12 @@ The following options are useful only for clients (that is, if addresses/ports. See SocksPort for an explanation of isolation flags. (Default: 0) +[[ClientDNSRejectInternalAddresses]] **ClientDNSRejectInternalAddresses** **0**|**1**:: + If true, Tor does not believe any anonymously retrieved DNS answer that + tells it that an address resolves to an internal address (like 127.0.0.1 or + 192.168.0.1). This option prevents certain browser-based attacks; don't + turn it off unless you know what you're doing. (Default: 1) + [[ClientRejectInternalAddresses]] **ClientRejectInternalAddresses** **0**|**1**:: If true, Tor does not try to fulfill requests to connect to an internal address (like 127.0.0.1 or 192.168.0.1) __unless a exit node is @@ -2507,7 +2513,7 @@ The following options are used for running a testing Tor network. 4 (for 40 seconds), 8, 16, 32, 60 ClientBootstrapConsensusMaxDownloadTries 80 ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries 80 - TestingClientDNSRejectInternalAddresses 0 + ClientDNSRejectInternalAddresses 0 ClientRejectInternalAddresses 0 CountPrivateBandwidth 1 ExitPolicyRejectPrivate 0 @@ -2718,13 +2724,6 @@ The following options are used for running a testing Tor network. we replace it and issue a new key? (Default: 3 hours for link and auth; 1 day for signing.) -[[ClientDNSRejectInternalAddresses]] [[TestingClientDNSRejectInternalAddresses]] **TestingClientDNSRejectInternalAddresses** **0**|**1**:: - If true, Tor does not believe any anonymously retrieved DNS answer that - tells it that an address resolves to an internal address (like 127.0.0.1 or - 192.168.0.1). This option prevents certain browser-based attacks; don't - turn it off unless you know what you're doing. (Default: 1) - - NON-PERSISTENT OPTIONS ---------------------- diff --git a/src/or/config.c b/src/or/config.c index e7fe3a5470..c87786cb9f 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -169,8 +169,6 @@ static config_abbrev_t option_abbrevs_[] = { { "BridgeAuthoritativeDirectory", "BridgeAuthoritativeDir", 0, 0}, { "HashedControlPassword", "__HashedControlSessionPassword", 1, 0}, { "VirtualAddrNetwork", "VirtualAddrNetworkIPv4", 0, 0}, - { "ClientDNSRejectInternalAddresses", - "TestingClientDNSRejectInternalAddresses", 0, 1, }, { NULL, NULL, 0, 0}, }; @@ -262,7 +260,7 @@ static config_var_t option_vars_[] = { V(CircuitsAvailableTimeout, INTERVAL, "0"), V(CircuitStreamTimeout, INTERVAL, "0"), V(CircuitPriorityHalflife, DOUBLE, "-100.0"), /*negative:'Use default'*/ - V(TestingClientDNSRejectInternalAddresses, BOOL,"1"), + V(ClientDNSRejectInternalAddresses, BOOL,"1"), V(ClientOnly, BOOL, "0"), V(ClientPreferIPv6ORPort, AUTOBOOL, "auto"), V(ClientPreferIPv6DirPort, AUTOBOOL, "auto"), @@ -648,7 +646,7 @@ static const config_var_t testing_tor_network_defaults[] = { "0, 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 16, 32, 60"), V(ClientBootstrapConsensusMaxDownloadTries, UINT, "80"), V(ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries, UINT, "80"), - V(TestingClientDNSRejectInternalAddresses, BOOL,"0"), + V(ClientDNSRejectInternalAddresses, BOOL,"0"), // deprecated in 0.2.9.2-alpha V(ClientRejectInternalAddresses, BOOL, "0"), V(CountPrivateBandwidth, BOOL, "1"), V(ExitPolicyRejectPrivate, BOOL, "0"), @@ -693,7 +691,14 @@ static const config_var_t testing_tor_network_defaults[] = { #undef OBSOLETE static const config_deprecation_t option_deprecation_notes_[] = { - /* Deprecated since 0.3.2.1-alpha. */ + /* Deprecated since 0.2.9.2-alpha... */ + { "AllowDotExit", "Unrestricted use of the .exit notation can be used for " + "a wide variety of application-level attacks." }, + { "ClientDNSRejectInternalAddresses", "Turning this on makes your client " + "easier to fingerprint, and may open you to esoteric attacks." }, + /* End of options deprecated since 0.2.9.2-alpha. */ + + /* 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 " @@ -4211,7 +4216,6 @@ options_validate(or_options_t *old_options, or_options_t *options, CHECK_DEFAULT(TestingSigningKeySlop); CHECK_DEFAULT(TestingAuthKeySlop); CHECK_DEFAULT(TestingLinkKeySlop); - CHECK_DEFAULT(TestingClientDNSRejectInternalAddresses); #undef CHECK_DEFAULT if (options->SigningKeyLifetime < options->TestingSigningKeySlop*2) diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index b9d8eeaff6..f178917f0b 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -1344,7 +1344,7 @@ connection_ap_handshake_rewrite(entry_connection_t *conn, /* Hang on, did we find an answer saying that this is a reverse lookup for * an internal address? If so, we should reject it if we're configured to * do so. */ - if (options->TestingClientDNSRejectInternalAddresses) { + if (options->ClientDNSRejectInternalAddresses) { /* Don't let clients try to do a reverse lookup on 10.0.0.1. */ tor_addr_t addr; int ok; diff --git a/src/or/or.h b/src/or/or.h index d9ab815cbc..809714b5e2 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -4204,7 +4204,7 @@ typedef struct { /** If true, do not believe anybody who tells us that a domain resolves * to an internal address, or that an internal address has a PTR mapping. * Helps avoid some cross-site attacks. */ - int TestingClientDNSRejectInternalAddresses; + int ClientDNSRejectInternalAddresses; /** If true, do not accept any requests to connect to internal addresses * over randomly chosen exits. */ diff --git a/src/or/relay.c b/src/or/relay.c index 48c1dd6f8d..09f70793d3 100644 --- a/src/or/relay.c +++ b/src/or/relay.c @@ -949,7 +949,7 @@ connection_ap_process_end_not_open( connection_mark_unattached_ap(conn, END_STREAM_REASON_TORPROTOCOL); return 0; } - if (get_options()->TestingClientDNSRejectInternalAddresses && + if (get_options()->ClientDNSRejectInternalAddresses && tor_addr_is_internal(&addr, 0)) { log_info(LD_APP,"Address '%s' resolved to internal. Closing,", safe_str(conn->socks_request->address)); @@ -1366,7 +1366,7 @@ connection_edge_process_resolved_cell(edge_connection_t *conn, goto done; } - if (get_options()->TestingClientDNSRejectInternalAddresses) { + if (get_options()->ClientDNSRejectInternalAddresses) { int orig_len = smartlist_len(resolved_addresses); SMARTLIST_FOREACH_BEGIN(resolved_addresses, address_ttl_t *, addr) { if (addr->hostname == NULL && tor_addr_is_internal(&addr->addr, 0)) { @@ -1459,7 +1459,7 @@ connection_edge_process_relay_cell_not_open( if (tor_addr_family(&addr) != AF_UNSPEC) { const sa_family_t family = tor_addr_family(&addr); if (tor_addr_is_null(&addr) || - (get_options()->TestingClientDNSRejectInternalAddresses && + (get_options()->ClientDNSRejectInternalAddresses && tor_addr_is_internal(&addr, 0))) { log_info(LD_APP, "...but it claims the IP address was %s. Closing.", fmt_addr(&addr)); diff --git a/src/test/test_relaycell.c b/src/test/test_relaycell.c index 9c010deece..eea1f5dc80 100644 --- a/src/test/test_relaycell.c +++ b/src/test/test_relaycell.c @@ -112,7 +112,7 @@ test_relaycell_resolved(void *arg) MOCK(connection_mark_unattached_ap_, mark_unattached_mock); MOCK(connection_ap_handshake_socks_resolved, socks_resolved_mock); - options->TestingClientDNSRejectInternalAddresses = 0; + options->ClientDNSRejectInternalAddresses = 0; SET_CELL(/* IPv4: 127.0.1.2, ttl 256 */ "\x04\x04\x7f\x00\x01\x02\x00\x00\x01\x00" @@ -151,7 +151,7 @@ test_relaycell_resolved(void *arg) /* But we may be discarding private answers. */ MOCK_RESET(); - options->TestingClientDNSRejectInternalAddresses = 1; + options->ClientDNSRejectInternalAddresses = 1; r = connection_edge_process_resolved_cell(edgeconn, &cell, &rh); tt_int_op(r, OP_EQ, 0); ASSERT_MARK_CALLED(END_STREAM_REASON_DONE| From e491c05f96387178da0958614084cd6ab30f5ea7 Mon Sep 17 00:00:00 2001 From: Sebastian Hahn Date: Sat, 4 Nov 2017 16:24:52 +0100 Subject: [PATCH 2/4] Undo deprecation of ClientDNSRejectInternalAddresses --- src/or/config.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/src/or/config.c b/src/or/config.c index c87786cb9f..bba2532000 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -646,7 +646,7 @@ static const config_var_t testing_tor_network_defaults[] = { "0, 1, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 16, 32, 60"), V(ClientBootstrapConsensusMaxDownloadTries, UINT, "80"), V(ClientBootstrapConsensusAuthorityOnlyMaxDownloadTries, UINT, "80"), - V(ClientDNSRejectInternalAddresses, BOOL,"0"), // deprecated in 0.2.9.2-alpha + V(ClientDNSRejectInternalAddresses, BOOL,"0"), V(ClientRejectInternalAddresses, BOOL, "0"), V(CountPrivateBandwidth, BOOL, "1"), V(ExitPolicyRejectPrivate, BOOL, "0"), @@ -694,8 +694,6 @@ static const config_deprecation_t option_deprecation_notes_[] = { /* Deprecated since 0.2.9.2-alpha... */ { "AllowDotExit", "Unrestricted use of the .exit notation can be used for " "a wide variety of application-level attacks." }, - { "ClientDNSRejectInternalAddresses", "Turning this on makes your client " - "easier to fingerprint, and may open you to esoteric attacks." }, /* End of options deprecated since 0.2.9.2-alpha. */ /* Deprecated since 0.3.2.0-alpha. */ From d3fee8b82395f95a925b9adcb7b3a66ae0d5a0ef Mon Sep 17 00:00:00 2001 From: Sebastian Hahn Date: Sat, 4 Nov 2017 16:37:41 +0100 Subject: [PATCH 3/4] ClientDNSRejectInternalAddresses in non-default networks Once again allow the flag to be set, unless the default network is used. Thanks to nickm for a suggestion for the workaround to a test failure. --- changes/ticket21031 | 5 +++++ doc/tor.1.txt | 6 +++--- src/or/config.c | 4 ++++ src/test/test_options.c | 5 +++-- 4 files changed, 15 insertions(+), 5 deletions(-) create mode 100644 changes/ticket21031 diff --git a/changes/ticket21031 b/changes/ticket21031 new file mode 100644 index 0000000000..1f97c45993 --- /dev/null +++ b/changes/ticket21031 @@ -0,0 +1,5 @@ + o New/reanimated features + - The ClientDNSRejectInternalAddresses flag can once again be set in + non-default tor networks. This also remves a deprecation of this + flag in 0.2.9.2-alpha. Closes ticket 21031. + diff --git a/doc/tor.1.txt b/doc/tor.1.txt index d701288af7..f052464332 100644 --- a/doc/tor.1.txt +++ b/doc/tor.1.txt @@ -1443,12 +1443,12 @@ The following options are useful only for clients (that is, if [[ClientDNSRejectInternalAddresses]] **ClientDNSRejectInternalAddresses** **0**|**1**:: If true, Tor does not believe any anonymously retrieved DNS answer that tells it that an address resolves to an internal address (like 127.0.0.1 or - 192.168.0.1). This option prevents certain browser-based attacks; don't - turn it off unless you know what you're doing. (Default: 1) + 192.168.0.1). This option prevents certain browser-based attacks; it + is not allowed to be set on the default network. (Default: 1) [[ClientRejectInternalAddresses]] **ClientRejectInternalAddresses** **0**|**1**:: If true, Tor does not try to fulfill requests to connect to an internal - address (like 127.0.0.1 or 192.168.0.1) __unless a exit node is + address (like 127.0.0.1 or 192.168.0.1) __unless an exit node is specifically requested__ (for example, via a .exit hostname, or a controller request). If true, multicast DNS hostnames for machines on the local network (of the form *.local) are also rejected. (Default: 1) diff --git a/src/or/config.c b/src/or/config.c index bba2532000..d6e1abaa10 100644 --- a/src/or/config.c +++ b/src/or/config.c @@ -4216,6 +4216,10 @@ options_validate(or_options_t *old_options, or_options_t *options, CHECK_DEFAULT(TestingLinkKeySlop); #undef CHECK_DEFAULT + if (!options->ClientDNSRejectInternalAddresses && + !(options->DirAuthorities || + (options->AlternateDirAuthority && options->AlternateBridgeAuthority))) + REJECT("ClientDNSRejectInternalAddresses used for default network."); if (options->SigningKeyLifetime < options->TestingSigningKeySlop*2) REJECT("SigningKeyLifetime is too short."); if (options->TestingLinkCertLifetime < options->TestingAuthKeySlop*2) diff --git a/src/test/test_options.c b/src/test/test_options.c index c55be35845..62732cabf7 100644 --- a/src/test/test_options.c +++ b/src/test/test_options.c @@ -398,11 +398,12 @@ fixed_get_uname(void) "V3AuthVoteDelay 20\n" \ "V3AuthDistDelay 20\n" \ "V3AuthNIntervalsValid 3\n" \ - "ClientUseIPv4 1\n" \ + "ClientUseIPv4 1\n" \ "VirtualAddrNetworkIPv4 127.192.0.0/10\n" \ "VirtualAddrNetworkIPv6 [FE80::]/10\n" \ "UseEntryGuards 1\n" \ - "Schedulers Vanilla\n" + "Schedulers Vanilla\n" \ + "ClientDNSRejectInternalAddresses 1\n" typedef struct { or_options_t *old_opt; From 7c1f33dd0e56bbd6a99ce7797bd03423675bdd9d Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Sun, 5 Nov 2017 14:09:07 -0500 Subject: [PATCH 4/4] ticket21031 changes file revised. --- changes/ticket21031 | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/changes/ticket21031 b/changes/ticket21031 index 1f97c45993..b081fb018f 100644 --- a/changes/ticket21031 +++ b/changes/ticket21031 @@ -1,5 +1,7 @@ - o New/reanimated features + o Minor features (removed deprecations): - The ClientDNSRejectInternalAddresses flag can once again be set in - non-default tor networks. This also remves a deprecation of this + non-testing Tor networks, so long as they do not use the default + directory authorities. + This change also removes the deprecation of this flag in 0.2.9.2-alpha. Closes ticket 21031.