Merge branch 'bug17027-reject-private-all-interfaces-v2' into bug16069-bug17027

src/test/test_policy.c:
Merged calls to policies_parse_exit_policy by adding additional arguments.
fixup to remaining instance of ~EXIT_POLICY_IPV6_ENABLED.
Compacting logic test now produces previous list length of 4, corrected this.

src/config/torrc.sample.in:
src/config/torrc.minimal.in-staging:
Merged torrc modification dates in favour of latest.

2 files changed, 118 insertions, 24 deletions

diff --git a/src/common/address.c b/src/common/address.c
index 066355373a..163db59ac4 100644
--- a/src/common/address.c
+++ b/src/common/address.c
@@ -1527,7 +1527,7 @@ get_interface_addresses_raw(int severity)
 }
 
 /** Return true iff <b>a</b> is a multicast address.  */
-static int
+STATIC int
 tor_addr_is_multicast(const tor_addr_t *a)
 {
   sa_family_t family = tor_addr_family(a);
@@ -1617,43 +1617,108 @@ get_interface_address6_via_udp_socket_hack(int severity,
   return r;
 }
 
-/** Set *<b>addr</b> to the IP address (if any) of whatever interface
- * connects to the Internet.  This address should only be used in checking
- * whether our address has changed.  Return 0 on success, -1 on failure.
+/** Set *<b>addr</b> to an arbitrary IP address (if any) of an interface that
+ * connects to the Internet.  Prefer public IP addresses to internal IP
+ * addresses.  This address should only be used in checking whether our
+ * address has changed, as it may be an internal IP address.  Return 0 on
+ * success, -1 on failure.
+ * Prefer get_interface_address6_list for a list of all addresses on all
+ * interfaces which connect to the Internet.
  */
 MOCK_IMPL(int,
 get_interface_address6,(int severity, sa_family_t family, tor_addr_t *addr))
 {
-  /* XXX really, this function should yield a smartlist of addresses. */
   smartlist_t *addrs;
+  int rv = -1;
   tor_assert(addr);
 
+  /* Get a list of public or internal IPs in arbitrary order */
+  addrs = get_interface_address6_list(severity, family, 1);
+
+  /* Find the first non-internal address, or the last internal address
+   * Ideally, we want the default route, see #12377 for details */
+  SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, a) {
+    tor_addr_copy(addr, a);
+    rv = 0;
+
+    /* If we found a non-internal address, declare success.  Otherwise,
+     * keep looking. */
+    if (!tor_addr_is_internal(a, 0))
+      break;
+  } SMARTLIST_FOREACH_END(a);
+
+  free_interface_address6_list(addrs);
+  return rv;
+}
+
+/** Free a smartlist of IP addresses returned by get_interface_address6_list.
+ */
+void
+free_interface_address6_list(smartlist_t *addrs)
+{
+  SMARTLIST_FOREACH(addrs, tor_addr_t *, a, tor_free(a));
+  smartlist_free(addrs);
+}
+
+/** Return a smartlist of the IP addresses of type family from all interfaces
+ * on the server. Excludes loopback and multicast addresses. Only includes
+ * internal addresses if include_internal is true. (Note that a relay behind
+ * NAT may use an internal address to connect to the Internet.)
+ * An empty smartlist means that there are no addresses of the selected type
+ * matching these criteria.
+ * Returns NULL on failure.
+ * Use free_interface_address6_list to free the returned list.
+ */
+MOCK_IMPL(smartlist_t *,get_interface_address6_list,(int severity,
+                                                     sa_family_t family,
+                                                     int include_internal))
+{
+  smartlist_t *addrs;
+  tor_addr_t addr;
+
   /* Try to do this the smart way if possible. */
   if ((addrs = get_interface_addresses_raw(severity))) {
-    int rv = -1;
-    SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, a) {
-      if (family != AF_UNSPEC && family != tor_addr_family(a))
+    SMARTLIST_FOREACH_BEGIN(addrs, tor_addr_t *, a)
+    {
+      if (family != AF_UNSPEC && family != tor_addr_family(a)) {
+        SMARTLIST_DEL_CURRENT(addrs, a);
+        tor_free(a);
         continue;
+      }
+
       if (tor_addr_is_loopback(a) ||
-          tor_addr_is_multicast(a))
+          tor_addr_is_multicast(a)) {
+        SMARTLIST_DEL_CURRENT(addrs, a);
+        tor_free(a);
         continue;
+      }
 
-      tor_addr_copy(addr, a);
-      rv = 0;
-
-      /* If we found a non-internal address, declare success.  Otherwise,
-       * keep looking. */
-      if (!tor_addr_is_internal(a, 0))
-        break;
+      if (!include_internal && tor_addr_is_internal(a, 0)) {
+        SMARTLIST_DEL_CURRENT(addrs, a);
+        tor_free(a);
+        continue;
+      }
     } SMARTLIST_FOREACH_END(a);
+  }
+
+  if (addrs && smartlist_len(addrs) > 0) {
+    return addrs;
+  }
 
-    SMARTLIST_FOREACH(addrs, tor_addr_t *, a, tor_free(a));
+  /* if we removed all entries as unsuitable */
+  if (addrs) {
     smartlist_free(addrs);
-    return rv;
   }
 
   /* Okay, the smart way is out. */
-  return get_interface_address6_via_udp_socket_hack(severity,family,addr);
+  get_interface_address6_via_udp_socket_hack(severity,family,&addr);
+  if (!include_internal && tor_addr_is_internal(&addr, 0)) {
+    return smartlist_new();
+  } else {
+    addrs = smartlist_new();
+    smartlist_add(addrs, tor_dup_addr(&addr));
+    return addrs;
+  }
 }
 
 /* ======
@@ -1895,10 +1960,13 @@ tor_dup_ip(uint32_t addr)
 }
 
 /**
- * Set *<b>addr</b> to the host-order IPv4 address (if any) of whatever
- * interface connects to the Internet.  This address should only be used in
- * checking whether our address has changed.  Return 0 on success, -1 on
- * failure.
+ * Set *<b>addr</b> to a host-order IPv4 address (if any) of an
+ * interface that connects to the Internet.  Prefer public IP addresses to
+ * internal IP addresses.  This address should only be used in checking
+ * whether our address has changed, as it may be an internal IPv4 address.
+ * Return 0 on success, -1 on failure.
+ * Prefer get_interface_address_list6 for a list of all IPv4 and IPv6
+ * addresses on all interfaces which connect to the Internet.
  */
 MOCK_IMPL(int,
 get_interface_address,(int severity, uint32_t *addr))
diff --git a/src/common/address.h b/src/common/address.h
index 90207c3338..7d49fb59bc 100644
--- a/src/common/address.h
+++ b/src/common/address.h
@@ -15,6 +15,7 @@
 #include "orconfig.h"
 #include "torint.h"
 #include "compat.h"
+#include "container.h"
 
 #ifdef ADDRESS_PRIVATE
 
@@ -43,7 +44,6 @@
 #endif
 
 // TODO win32 specific includes
-#include "container.h"
 #endif // ADDRESS_PRIVATE
 
 /** The number of bits from an address to consider while doing a masked
@@ -190,8 +190,13 @@ char *tor_dup_addr(const tor_addr_t *addr) ATTR_MALLOC;
 const char *fmt_addr_impl(const tor_addr_t *addr, int decorate);
 const char *fmt_addrport(const tor_addr_t *addr, uint16_t port);
 const char * fmt_addr32(uint32_t addr);
+
 MOCK_DECL(int,get_interface_address6,(int severity, sa_family_t family,
 tor_addr_t *addr));
+void free_interface_address6_list(smartlist_t * addrs);
+MOCK_DECL(smartlist_t *,get_interface_address6_list,(int severity,
+                                                     sa_family_t family,
+                                                     int include_internal));
 
 /** Flag to specify how to do a comparison between addresses.  In an "exact"
  * comparison, addresses are equivalent only if they are in the same family
@@ -281,11 +286,32 @@ int addr_mask_get_bits(uint32_t mask);
 int tor_inet_ntoa(const struct in_addr *in, char *buf, size_t buf_len);
 char *tor_dup_ip(uint32_t addr) ATTR_MALLOC;
 MOCK_DECL(int,get_interface_address,(int severity, uint32_t *addr));
+/** Free a smartlist of IP addresses returned by get_interface_address_list.
+ */
+static INLINE void
+free_interface_address_list(smartlist_t *addrs)
+{
+  free_interface_address6_list(addrs);
+}
+/** Return a smartlist of the IPv4 addresses of all interfaces on the server.
+ * Excludes loopback and multicast addresses. Only includes internal addresses
+ * if include_internal is true. (Note that a relay behind NAT may use an
+ * internal address to connect to the Internet.)
+ * An empty smartlist means that there are no IPv4 addresses.
+ * Returns NULL on failure.
+ * Use free_interface_address_list to free the returned list.
+ */
+static INLINE smartlist_t *
+get_interface_address_list(int severity, int include_internal)
+{
+  return get_interface_address6_list(severity, AF_INET, include_internal);
+}
 
 tor_addr_port_t *tor_addr_port_new(const tor_addr_t *addr, uint16_t port);
 
 #ifdef ADDRESS_PRIVATE
 STATIC smartlist_t *get_interface_addresses_raw(int severity);
+STATIC int tor_addr_is_multicast(const tor_addr_t *a);
 STATIC int get_interface_address6_via_udp_socket_hack(int severity,
                                                       sa_family_t family,
                                                       tor_addr_t *addr);