From ae5800cd9faccd8c1319601cac7f6c76c4beb288 Mon Sep 17 00:00:00 2001 From: David Goulet Date: Wed, 10 Feb 2021 11:46:32 -0500 Subject: relay: Allow RFC1918 addresses for non public relays In other words, if PublishServerDescriptor is set to 0 and AssumeReachable to 1, then allow a relay to hold a RFC1918 address. Reasons for this are documented in #40208 Fixes #40208 Signed-off-by: David Goulet --- changes/ticket40208 | 6 ++++++ src/app/config/resolve_addr.c | 14 +++++++++++++- src/test/test_config.c | 17 +++++++++++++++++ 3 files changed, 36 insertions(+), 1 deletion(-) create mode 100644 changes/ticket40208 diff --git a/changes/ticket40208 b/changes/ticket40208 new file mode 100644 index 0000000000..5a3a1aa55e --- /dev/null +++ b/changes/ticket40208 @@ -0,0 +1,6 @@ + o Minor bugfixes (relay): + - Allow relays to have a RFC1918 address if PublishServerDescriptor is set + to 0 and AssumeReachable is set to 1. This is to support the use case of a + bridge on a local network that can be used by restricted users on that + network to reach the Tor network. Fixes bug 40208; bugfix on + 0.4.5.1-alpha. diff --git a/src/app/config/resolve_addr.c b/src/app/config/resolve_addr.c index 080cb967bc..86db6ba680 100644 --- a/src/app/config/resolve_addr.c +++ b/src/app/config/resolve_addr.c @@ -193,7 +193,19 @@ address_can_be_used(const tor_addr_t *addr, const or_options_t *options, goto allow; } - /* We have a private IP address. It is allowed only if we set custom + /* We allow internal addresses to be used if the PublishServerDescriptor is + * unset and AssumeReachable (or for IPv6) is set. + * + * This is to cover the case where a relay/bridge might be run behind a + * firewall on a local network to users can reach the network through it + * using Tor Browser for instance. */ + if (options->PublishServerDescriptor_ == NO_DIRINFO && + (options->AssumeReachable || + (tor_addr_family(addr) == AF_INET6 && options->AssumeReachableIPv6))) { + goto allow; + } + + /* We have a private IP address. This is also allowed if we set custom * directory authorities. */ if (using_default_dir_authorities(options)) { log_fn(warn_severity, LD_CONFIG, diff --git a/src/test/test_config.c b/src/test/test_config.c index 4eb4ac9cf5..eacf12a25f 100644 --- a/src/test/test_config.c +++ b/src/test/test_config.c @@ -1460,6 +1460,7 @@ test_config_find_my_address(void *arg) options = options_new(); options_init(options); + options->PublishServerDescriptor_ = V3_DIRINFO; /* * Case 0: @@ -1782,6 +1783,22 @@ test_config_find_my_address(void *arg) VALIDATE_FOUND_ADDRESS(true, RESOLVED_ADDR_INTERFACE, NULL); CLEANUP_FOUND_ADDRESS; + /* + * Case 15: Address is a local address (internal) but we unset + * PublishServerDescriptor_ so we are allowed to hold it. + */ + options->PublishServerDescriptor_ = NO_DIRINFO; + if (p->family == AF_INET) { + options->AssumeReachable = 1; + } + config_line_append(&options->Address, "Address", p->internal_ip); + + tor_addr_parse(&test_addr, p->internal_ip); + retval = find_my_address(options, p->family, LOG_NOTICE, &resolved_addr, + &method_used, &hostname_out); + VALIDATE_FOUND_ADDRESS(true, RESOLVED_ADDR_CONFIGURED, NULL); + CLEANUP_FOUND_ADDRESS; + UNMOCK(get_interface_address6); UNMOCK(tor_gethostname); UNMOCK(tor_addr_lookup); -- cgit v1.2.3-54-g00ecf