test: Add test for exits blocking reentry to the network

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/feature/nodelist/dirlist.c

@@ -71,8 +71,8 @@ add_trusted_dir_to_nodelist_addr_set(const dir_server_t *dir)
 
 /** Go over the trusted directory server list and add their address(es) to the
  * nodelist address set. This is called every time a new consensus is set. */
-void
+MOCK_IMPL(void,
-dirlist_add_trusted_dir_addresses(void)
+dirlist_add_trusted_dir_addresses, (void))
 {
   if (!trusted_dir_servers) {
     return;

src/feature/nodelist/dirlist.h

@@ -44,6 +44,6 @@ void dir_server_add(dir_server_t *ent);
 void clear_dir_servers(void);
 void dirlist_free_all(void);
 
-void dirlist_add_trusted_dir_addresses(void);
+MOCK_DECL(void, dirlist_add_trusted_dir_addresses, (void));
 
 #endif

src/test/test_address_set.c

@@ -4,6 +4,7 @@
 #include "core/or/or.h"
 #include "lib/crypt_ops/crypto_rand.h"
 #include "core/or/address_set.h"
+#include "feature/nodelist/dirlist.h"
 #include "feature/nodelist/microdesc.h"
 #include "feature/nodelist/networkstatus.h"
 #include "feature/nodelist/nodelist.h"
@@ -31,6 +32,12 @@ mock_networkstatus_get_latest_consensus_by_flavor(consensus_flavor_t f)
   return dummy_ns;
 }
 
+static void
+mock_dirlist_add_trusted_dir_addresses(void)
+{
+  return;
+}
+
 /* Number of address a single node_t can have. Default to the production
  * value. This is to control the size of the bloom filter. */
 static int addr_per_node = 2;
@@ -169,11 +176,91 @@ test_nodelist(void *arg)
   UNMOCK(get_estimated_address_per_node);
 }
 
+/** Test that the no-reentry exit filter works as intended */
+static void
+test_exit_no_reentry(void *arg)
+{
+  routerstatus_t *rs = NULL; microdesc_t *md = NULL; routerinfo_t *ri = NULL;
+  (void) arg;
+
+  MOCK(networkstatus_get_latest_consensus,
+       mock_networkstatus_get_latest_consensus);
+  MOCK(networkstatus_get_latest_consensus_by_flavor,
+       mock_networkstatus_get_latest_consensus_by_flavor);
+  MOCK(get_estimated_address_per_node,
+       mock_get_estimated_address_per_node);
+  MOCK(dirlist_add_trusted_dir_addresses,
+       mock_dirlist_add_trusted_dir_addresses);
+
+  dummy_ns = tor_malloc_zero(sizeof(*dummy_ns));
+  dummy_ns->flavor = FLAV_MICRODESC;
+  dummy_ns->routerstatus_list = smartlist_new();
+
+  tor_addr_t addr_v4, addr_v6, dummy_addr;
+  tor_addr_parse(&addr_v4, "42.42.42.42");
+  tor_addr_parse(&addr_v6, "1:2:3:4::");
+  memset(&dummy_addr, 'A', sizeof(dummy_addr));
+
+  /* This will make the nodelist bloom filter very large
+   * (the_nodelist->node_addrs) so we will fail the contain test rarely. */
+  addr_per_node = 1024;
+
+  /* After this point the nodelist is populated with the directory authorities
+   * address and ports */
+  nodelist_set_consensus(dummy_ns);
+
+  /* The address set is empty. Try it anyway */
+  tt_assert(!nodelist_reentry_probably_contains(&addr_v4, 244));
+  tt_assert(!nodelist_reentry_probably_contains(&addr_v6, 244));
+
+  /* Now let's populate the network */
+  md = tor_malloc_zero(sizeof(*md));
+  ri = tor_malloc_zero(sizeof(*ri));
+  rs = tor_malloc_zero(sizeof(*rs));
+  crypto_rand(rs->identity_digest, sizeof(rs->identity_digest));
+  crypto_rand(md->digest, sizeof(md->digest));
+  memcpy(rs->descriptor_digest, md->digest, DIGEST256_LEN);
+
+  /* Setup the rs, ri and md addresses. */
+  rs->addr = tor_addr_to_ipv4h(&addr_v4);
+  rs->or_port = 444;
+  tor_addr_parse(&rs->ipv6_addr, "1:2:3:4::");
+  rs->ipv6_orport = 666;
+  ri->addr = tor_addr_to_ipv4h(&addr_v4);
+  tor_addr_parse(&ri->ipv6_addr, "1:2:3:4::");
+  tor_addr_parse(&md->ipv6_addr, "1:2:3:4::");
+
+  /* Add the rs to the consensus becoming a node_t. */
+  smartlist_add(dummy_ns->routerstatus_list, rs);
+  nodelist_set_consensus(dummy_ns);
+
+  /* Now that the nodelist is populated let's do some retry attempts */
+
+  /* First let's try an address that is on the no-reentry list, but with a
+     different port */
+  tt_assert(!nodelist_reentry_probably_contains(&addr_v4, 666));
+  tt_assert(!nodelist_reentry_probably_contains(&addr_v6, 444));
+
+  /* OK now let's try with the right address and right port */
+  tt_assert(nodelist_reentry_probably_contains(&addr_v4, 444));
+  tt_assert(nodelist_reentry_probably_contains(&addr_v6, 666));
+
+ done:
+  routerstatus_free(rs); routerinfo_free(ri); microdesc_free(md);
+  smartlist_clear(dummy_ns->routerstatus_list);
+  networkstatus_vote_free(dummy_ns);
+  UNMOCK(networkstatus_get_latest_consensus);
+  UNMOCK(networkstatus_get_latest_consensus_by_flavor);
+  UNMOCK(get_estimated_address_per_node);
+  UNMOCK(dirlist_add_trusted_dir_addresses);
+}
+
 struct testcase_t address_set_tests[] = {
   { "contains", test_contains, TT_FORK,
     NULL, NULL },
   { "nodelist", test_nodelist, TT_FORK,
     NULL, NULL },
+  { "exit_no_reentry", test_exit_no_reentry, TT_FORK, NULL, NULL },
 
   END_OF_TESTCASES
 };