diff --git a/changes/change_separate_exit_and_relay.txt b/changes/change_separate_exit_and_relay.txt
new file mode 100644
index 0000000000..28db1d20fe
--- /dev/null
+++ b/changes/change_separate_exit_and_relay.txt
@@ -0,0 +1,2 @@
+- Minor features:
+ - Allow separation of exit and relay traffic to different source IP addresses (Ticket #17975). Written by Michael Sonntag.
diff --git a/doc/tor.1.txt b/doc/tor.1.txt
index da2a61f4b6..de2e2b4a04 100644
--- a/doc/tor.1.txt
+++ b/doc/tor.1.txt
@@ -640,6 +640,20 @@ GENERAL OPTIONS
This setting will be ignored for connections to the loopback addresses
(127.0.0.0/8 and ::1).
+[[OutboundBindAddressOR]] **OutboundBindAddressOR** __IP__::
+ Make all outbound non-exit (=relay and other) connections originate from the IP
+ address specified. This option overrides **OutboundBindAddress** for the same
+ IP version. This option may be used twice, once with an IPv4 address and once
+ with an IPv6 address. This setting will be ignored for connections to the
+ loopback addresses (127.0.0.0/8 and ::1).
+
+[[OutboundBindAddressExit]] **OutboundBindAddressExit** __IP__::
+ Make all outbound exit connections originate from the IP address specified. This
+ option overrides **OutboundBindAddress** for the same IP version. This option
+ may be used twice, once with an IPv4 address and once with an IPv6 address. This
+ setting will be ignored for connections to the loopback addresses (127.0.0.0/8
+ and ::1).
+
[[PidFile]] **PidFile** __FILE__::
On startup, write our PID to FILE. On clean shutdown, remove
FILE. Can not be changed while tor is running.
diff --git a/src/config/torrc.sample.in b/src/config/torrc.sample.in
index 5328206da9..37777443ac 100644
--- a/src/config/torrc.sample.in
+++ b/src/config/torrc.sample.in
@@ -95,7 +95,12 @@
## If you have multiple network interfaces, you can specify one for
## outgoing traffic to use.
-# OutboundBindAddress 10.0.0.5
+## OutboundBindAddressExit will be used for all exit traffic, while
+## OutboundBindAddressOR will be used for all other connections.
+## If you do not wish to differentiate, use OutboundBindAddress to
+## specify the same address for both in a single line.
+#OutboundBindAddressExit 10.0.0.4
+#OutboundBindAddressOR 10.0.0.5
## A handle for your relay, so people don't have to refer to it by key.
## Nicknames must be between 1 and 19 characters inclusive, and must
diff --git a/src/or/config.c b/src/or/config.c
index e5078ad656..d0ca561e1f 100644
--- a/src/or/config.c
+++ b/src/or/config.c
@@ -411,6 +411,8 @@ static config_var_t option_vars_[] = {
V(ORListenAddress, LINELIST, NULL),
VPORT(ORPort),
V(OutboundBindAddress, LINELIST, NULL),
+ V(OutboundBindAddressOR, LINELIST, NULL),
+ V(OutboundBindAddressExit, LINELIST, NULL),
OBSOLETE("PathBiasDisableRate"),
V(PathBiasCircThreshold, INT, "-1"),
@@ -7917,57 +7919,80 @@ getinfo_helper_config(control_connection_t *conn,
return 0;
}
+/* Check whether an address has already been set against the options
+ * depending on address family and destination type. Any exsting
+ * value will lead to a fail, even if it is the same value. If not
+ * set and not only validating, copy it into this location too.
+ * Returns 0 on success or -1 if this address is already set.
+ */
+static int
+verify_and_store_outbound_address(sa_family_t family, tor_addr_t *addr,
+ outbound_addr_t type, or_options_t *options, int validate_only)
+{
+ if (type>=OUTBOUND_ADDR_MAX || (family!=AF_INET && family!=AF_INET6)) {
+ return -1;
+ }
+ int fam_index=0;
+ if (family==AF_INET6) {
+ fam_index=1;
+ }
+ tor_addr_t *dest=&options->OutboundBindAddresses[type][fam_index];
+ if (!tor_addr_is_null(dest)) {
+ return -1;
+ }
+ if (!validate_only) {
+ tor_addr_copy(dest, addr);
+ }
+ return 0;
+}
+
+/* Parse a list of address lines for a specific destination type.
+ * Will store them into the options if not validate_only. If a
+ * problem occurs, a suitable error message is store in msg.
+ * Returns 0 on success or -1 if any address is already set.
+ */
+static int
+parse_outbound_address_lines(const config_line_t *lines, outbound_addr_t type,
+ or_options_t *options, int validate_only, char **msg)
+{
+ tor_addr_t addr;
+ sa_family_t family;
+ while (lines) {
+ family = tor_addr_parse(&addr, lines->value);
+ if (verify_and_store_outbound_address(family, &addr, type,
+ options, validate_only)) {
+ if (msg)
+ tor_asprintf(msg, "Multiple%s%s outbound bind addresses "
+ "configured: %s",
+ family==AF_INET?" IPv4":(family==AF_INET6?" IPv6":""),
+ type==OUTBOUND_ADDR_OR?" OR":
+ (type==OUTBOUND_ADDR_EXIT?" exit":""), lines->value);
+ return -1;
+ }
+ lines = lines->next;
+ }
+ return 0;
+}
+
/** Parse outbound bind address option lines. If validate_only
- * is not 0 update OutboundBindAddressIPv4_ and
- * OutboundBindAddressIPv6_ in options. On failure, set
- * msg (if provided) to a newly allocated string containing a
- * description of the problem and return -1. */
+ * is not 0 update OutboundBindAddresses in options.
+ * Only one address can be set for any of these values.
+ * On failure, set msg (if provided) to a newly allocated string
+ * containing a description of the problem and return -1.
+ */
static int
parse_outbound_addresses(or_options_t *options, int validate_only, char **msg)
{
- const config_line_t *lines = options->OutboundBindAddress;
- int found_v4 = 0, found_v6 = 0;
-
if (!validate_only) {
- memset(&options->OutboundBindAddressIPv4_, 0,
- sizeof(options->OutboundBindAddressIPv4_));
- memset(&options->OutboundBindAddressIPv6_, 0,
- sizeof(options->OutboundBindAddressIPv6_));
- }
- while (lines) {
- tor_addr_t addr, *dst_addr = NULL;
- int af = tor_addr_parse(&addr, lines->value);
- switch (af) {
- case AF_INET:
- if (found_v4) {
- if (msg)
- tor_asprintf(msg, "Multiple IPv4 outbound bind addresses "
- "configured: %s", lines->value);
- return -1;
- }
- found_v4 = 1;
- dst_addr = &options->OutboundBindAddressIPv4_;
- break;
- case AF_INET6:
- if (found_v6) {
- if (msg)
- tor_asprintf(msg, "Multiple IPv6 outbound bind addresses "
- "configured: %s", lines->value);
- return -1;
- }
- found_v6 = 1;
- dst_addr = &options->OutboundBindAddressIPv6_;
- break;
- default:
- if (msg)
- tor_asprintf(msg, "Outbound bind address '%s' didn't parse.",
- lines->value);
- return -1;
- }
- if (!validate_only)
- tor_addr_copy(dst_addr, &addr);
- lines = lines->next;
+ memset(&options->OutboundBindAddresses, 0,
+ sizeof(options->OutboundBindAddresses));
}
+ parse_outbound_address_lines(options->OutboundBindAddress,
+ OUTBOUND_ADDR_EXIT_AND_OR, options, validate_only, msg);
+ parse_outbound_address_lines(options->OutboundBindAddressOR,
+ OUTBOUND_ADDR_OR, options, validate_only, msg);
+ parse_outbound_address_lines(options->OutboundBindAddressExit,
+ OUTBOUND_ADDR_EXIT, options, validate_only, msg);
return 0;
}
diff --git a/src/or/connection.c b/src/or/connection.c
index 7e0ee4551e..188276026f 100644
--- a/src/or/connection.c
+++ b/src/or/connection.c
@@ -134,6 +134,8 @@ static int connection_read_https_proxy_response(connection_t *conn);
static void connection_send_socks5_connect(connection_t *conn);
static const char *proxy_type_to_string(int proxy_type);
static int get_proxy_type(void);
+const tor_addr_t *conn_get_outbound_address(sa_family_t family,
+ const or_options_t *options, unsigned int conn_type);
/** The last addresses that our network interface seemed to have been
* binding to. We use this as one way to detect when our IP changes.
@@ -1771,7 +1773,7 @@ connection_connect_sockaddr,(connection_t *conn,
/*
* We've got the socket open; give the OOS handler a chance to check
- * against configuured maximum socket number, but tell it no exhaustion
+ * against configured maximum socket number, but tell it no exhaustion
* failure.
*/
connection_check_oos(get_n_open_sockets(), 0);
@@ -1890,6 +1892,55 @@ connection_connect_log_client_use_ip_version(const connection_t *conn)
}
}
+/** Retrieve the outbound address depending on the protocol (IPv4 or IPv6)
+ * and the connection type (relay, exit, ...)
+ * Return a socket address or NULL in case nothing is configured.
+ **/
+const tor_addr_t *
+conn_get_outbound_address(sa_family_t family,
+ const or_options_t *options, unsigned int conn_type)
+{
+ const tor_addr_t *ext_addr = NULL;
+
+ int fam_index;
+ switch (family) {
+ case AF_INET:
+ fam_index = 0;
+ break;
+ case AF_INET6:
+ fam_index = 1;
+ break;
+ default:
+ return NULL;
+ }
+
+ // If an exit connection, use the exit address (if present)
+ if (conn_type == CONN_TYPE_EXIT) {
+ if (!tor_addr_is_null(
+ &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT][fam_index])) {
+ ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT]
+ [fam_index];
+ } else if (!tor_addr_is_null(
+ &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
+ [fam_index])) {
+ ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
+ [fam_index];
+ }
+ } else { // All non-exit connections
+ if (!tor_addr_is_null(
+ &options->OutboundBindAddresses[OUTBOUND_ADDR_OR][fam_index])) {
+ ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_OR]
+ [fam_index];
+ } else if (!tor_addr_is_null(
+ &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
+ [fam_index])) {
+ ext_addr = &options->OutboundBindAddresses[OUTBOUND_ADDR_EXIT_AND_OR]
+ [fam_index];
+ }
+ }
+ return ext_addr;
+}
+
/** Take conn, make a nonblocking socket; try to connect to
* addr:port (port arrives in *host order*). If fail, return -1 and if
* applicable put your best guess about errno into *socket_error.
@@ -1911,26 +1962,15 @@ connection_connect(connection_t *conn, const char *address,
struct sockaddr *bind_addr = NULL;
struct sockaddr *dest_addr;
int dest_addr_len, bind_addr_len = 0;
- const or_options_t *options = get_options();
- int protocol_family;
/* Log if we didn't stick to ClientUseIPv4/6 or ClientPreferIPv6OR/DirPort
*/
connection_connect_log_client_use_ip_version(conn);
- if (tor_addr_family(addr) == AF_INET6)
- protocol_family = PF_INET6;
- else
- protocol_family = PF_INET;
-
if (!tor_addr_is_loopback(addr)) {
const tor_addr_t *ext_addr = NULL;
- if (protocol_family == AF_INET &&
- !tor_addr_is_null(&options->OutboundBindAddressIPv4_))
- ext_addr = &options->OutboundBindAddressIPv4_;
- else if (protocol_family == AF_INET6 &&
- !tor_addr_is_null(&options->OutboundBindAddressIPv6_))
- ext_addr = &options->OutboundBindAddressIPv6_;
+ ext_addr = conn_get_outbound_address(tor_addr_family(addr), get_options(),
+ conn->type);
if (ext_addr) {
memset(&bind_addr_ss, 0, sizeof(bind_addr_ss));
bind_addr_len = tor_addr_to_sockaddr(ext_addr, 0,
diff --git a/src/or/or.h b/src/or/or.h
index 80ce704e85..18fff78942 100644
--- a/src/or/or.h
+++ b/src/or/or.h
@@ -3545,6 +3545,12 @@ typedef struct routerset_t routerset_t;
* to pick its own port. */
#define CFG_AUTO_PORT 0xc4005e
+/** Enumeration of outbound address configuration types:
+ * Exit-only, OR-only, or both */
+typedef enum {OUTBOUND_ADDR_EXIT, OUTBOUND_ADDR_OR,
+ OUTBOUND_ADDR_EXIT_AND_OR,
+ OUTBOUND_ADDR_MAX} outbound_addr_t;
+
/** Configuration options for a Tor process. */
typedef struct {
uint32_t magic_;
@@ -3628,10 +3634,14 @@ typedef struct {
config_line_t *ControlListenAddress;
/** Local address to bind outbound sockets */
config_line_t *OutboundBindAddress;
- /** IPv4 address derived from OutboundBindAddress. */
- tor_addr_t OutboundBindAddressIPv4_;
- /** IPv6 address derived from OutboundBindAddress. */
- tor_addr_t OutboundBindAddressIPv6_;
+ /** Local address to bind outbound relay sockets */
+ config_line_t *OutboundBindAddressOR;
+ /** Local address to bind outbound exit sockets */
+ config_line_t *OutboundBindAddressExit;
+ /** Addresses derived from the various OutboundBindAddress lines.
+ * [][0] is IPv4, [][1] is IPv6
+ */
+ tor_addr_t OutboundBindAddresses[OUTBOUND_ADDR_MAX][2];
/** Directory server only: which versions of
* Tor should we tell users to run? */
config_line_t *RecommendedVersions;
diff --git a/src/or/policies.c b/src/or/policies.c
index 84600f7ef8..aea1b11829 100644
--- a/src/or/policies.c
+++ b/src/or/policies.c
@@ -2019,10 +2019,10 @@ policies_copy_ipv4h_to_smartlist(smartlist_t *addr_list, uint32_t ipv4h_addr)
}
}
-/** Helper function that adds copies of
- * or_options->OutboundBindAddressIPv[4|6]_ to a smartlist as tor_addr_t *, as
- * long as or_options is non-NULL, and the addresses are not
- * tor_addr_is_null(), by passing them to policies_add_addr_to_smartlist.
+/** Helper function that adds copies of or_options->OutboundBindAddresses
+ * to a smartlist as tor_addr_t *, as long as or_options is non-NULL, and
+ * the addresses are not tor_addr_is_null(), by passing them to
+ * policies_add_addr_to_smartlist.
*
* The caller is responsible for freeing all the tor_addr_t* in the smartlist.
*/
@@ -2031,10 +2031,14 @@ policies_copy_outbound_addresses_to_smartlist(smartlist_t *addr_list,
const or_options_t *or_options)
{
if (or_options) {
- policies_copy_addr_to_smartlist(addr_list,
- &or_options->OutboundBindAddressIPv4_);
- policies_copy_addr_to_smartlist(addr_list,
- &or_options->OutboundBindAddressIPv6_);
+ for (int i=0;iOutboundBindAddresses[i][j])) {
+ policies_copy_addr_to_smartlist(addr_list,
+ &or_options->OutboundBindAddresses[i][j]);
+ }
+ }
+ }
}
}
@@ -2051,10 +2055,10 @@ policies_copy_outbound_addresses_to_smartlist(smartlist_t *addr_list,
* - if ipv6_local_address is non-NULL, and not the null tor_addr_t, add it
* to the list of configured addresses.
* If or_options->ExitPolicyRejectLocalInterfaces is true:
- * - if or_options->OutboundBindAddressIPv4_ is not the null tor_addr_t, add
- * it to the list of configured addresses.
- * - if or_options->OutboundBindAddressIPv6_ is not the null tor_addr_t, add
- * it to the list of configured addresses.
+ * - if or_options->OutboundBindAddresses[][0] (=IPv4) is not the null
+ * tor_addr_t, add it to the list of configured addresses.
+ * - if or_options->OutboundBindAddresses[][1] (=IPv6) is not the null
+ * tor_addr_t, add it to the list of configured addresses.
*
* If or_options->BridgeRelay is false, append entries of default
* Tor exit policy into result smartlist.
diff --git a/src/test/test_policy.c b/src/test/test_policy.c
index 4df40f618e..71a31118a1 100644
--- a/src/test/test_policy.c
+++ b/src/test/test_policy.c
@@ -1083,8 +1083,12 @@ test_policies_getinfo_helper_policies(void *arg)
append_exit_policy_string(&mock_my_routerinfo.exit_policy, "reject *6:*");
mock_options.IPv6Exit = 1;
- tor_addr_from_ipv4h(&mock_options.OutboundBindAddressIPv4_, TEST_IPV4_ADDR);
- tor_addr_parse(&mock_options.OutboundBindAddressIPv6_, TEST_IPV6_ADDR);
+ tor_addr_from_ipv4h(
+ &mock_options.OutboundBindAddresses[OUTBOUND_ADDR_EXIT][0],
+ TEST_IPV4_ADDR);
+ tor_addr_parse(
+ &mock_options.OutboundBindAddresses[OUTBOUND_ADDR_EXIT][1],
+ TEST_IPV6_ADDR);
mock_options.ExitPolicyRejectPrivate = 1;
mock_options.ExitPolicyRejectLocalInterfaces = 1;