Merge branch 'maint-0.2.9' into maint-0.3.0

5 files changed, 80 insertions, 18 deletions

diff --git a/changes/bug22460_case2 b/changes/bug22460_case2
new file mode 100644
index 0000000000..0a11759832
--- /dev/null
+++ b/changes/bug22460_case2
@@ -0,0 +1,8 @@
+  o Major bugfixes (relay, link handshake):
+
+    - When performing the v3 link handshake on a TLS connection, report that
+      we have the x509 certificate that we actually used on that connection,
+      even if we have changed certificates since that connection was first
+      opened. Previously, we would claim to have used our most recent x509
+      link certificate, which would sometimes make the link handshake fail.
+      Fixes one case of bug 22460; bugfix on 0.2.3.6-alpha.
diff --git a/src/common/tortls.c b/src/common/tortls.c
index 1594f3be00..e3e8830b3e 100644
--- a/src/common/tortls.c
+++ b/src/common/tortls.c
@@ -704,11 +704,13 @@ MOCK_IMPL(STATIC tor_x509_cert_t *,
   return cert;
 }
 
-/** Return a copy of <b>cert</b> */
+/** Return a new copy of <b>cert</b>. */
 tor_x509_cert_t *
 tor_x509_cert_dup(const tor_x509_cert_t *cert)
 {
-  return tor_x509_cert_new(X509_dup(cert->cert));
+  tor_assert(cert);
+  X509 *x509 = cert->cert;
+  return tor_x509_cert_new(X509_dup(x509));
 }
 
 /** Read a DER-encoded X509 cert, of length exactly <b>certificate_len</b>,
@@ -2046,7 +2048,8 @@ tor_tls_peer_has_cert(tor_tls_t *tls)
   return 1;
 }
 
-/** Return the peer certificate, or NULL if there isn't one. */
+/** Return a newly allocated copy of the peer certificate, or NULL if there
+ * isn't one. */
 MOCK_IMPL(tor_x509_cert_t *,
 tor_tls_get_peer_cert,(tor_tls_t *tls))
 {
@@ -2058,6 +2061,24 @@ tor_tls_get_peer_cert,(tor_tls_t *tls))
   return tor_x509_cert_new(cert);
 }
 
+/** Return a newly allocated copy of the cerficate we used on the connection,
+ * or NULL if somehow we didn't use one. */
+MOCK_IMPL(tor_x509_cert_t *,
+tor_tls_get_own_cert,(tor_tls_t *tls))
+{
+  X509 *cert = SSL_get_certificate(tls->ssl);
+  tls_log_errors(tls, LOG_WARN, LD_HANDSHAKE,
+                 "getting own-connection certificate");
+  if (!cert)
+    return NULL;
+  /* Fun inconsistency: SSL_get_peer_certificate increments the reference
+   * count, but SSL_get_certificate does not. */
+  X509 *duplicate = X509_dup(cert);
+  if (BUG(duplicate == NULL))
+    return NULL;
+  return tor_x509_cert_new(duplicate);
+}
+
 /** Warn that a certificate lifetime extends through a certain range. */
 static void
 log_cert_lifetime(int severity, const X509 *cert, const char *problem,
diff --git a/src/common/tortls.h b/src/common/tortls.h
index 6510fdbe64..bb7701cc4b 100644
--- a/src/common/tortls.h
+++ b/src/common/tortls.h
@@ -199,6 +199,7 @@ int tor_tls_is_server(tor_tls_t *tls);
 void tor_tls_free(tor_tls_t *tls);
 int tor_tls_peer_has_cert(tor_tls_t *tls);
 MOCK_DECL(tor_x509_cert_t *,tor_tls_get_peer_cert,(tor_tls_t *tls));
+MOCK_DECL(tor_x509_cert_t *,tor_tls_get_own_cert,(tor_tls_t *tls));
 int tor_tls_verify(int severity, tor_tls_t *tls, crypto_pk_t **identity);
 int tor_tls_check_lifetime(int severity,
                            tor_tls_t *tls, time_t now,
diff --git a/src/or/connection_or.c b/src/or/connection_or.c
index cefe42c4db..b9ac9b2c5d 100644
--- a/src/or/connection_or.c
+++ b/src/or/connection_or.c
@@ -2270,7 +2270,8 @@ add_ed25519_cert(certs_cell_t *certs_cell,
 int
 connection_or_send_certs_cell(or_connection_t *conn)
 {
-  const tor_x509_cert_t *link_cert = NULL, *id_cert = NULL;
+  const tor_x509_cert_t *global_link_cert = NULL, *id_cert = NULL;
+  tor_x509_cert_t *own_link_cert = NULL;
   var_cell_t *cell;
 
   certs_cell_t *certs_cell = NULL;
@@ -2283,21 +2284,26 @@ connection_or_send_certs_cell(or_connection_t *conn)
   const int conn_in_server_mode = ! conn->handshake_state->started_here;
 
   /* Get the encoded values of the X509 certificates */
-  if (tor_tls_get_my_certs(conn_in_server_mode, &link_cert, &id_cert) < 0)
+  if (tor_tls_get_my_certs(conn_in_server_mode,
+                           &global_link_cert, &id_cert) < 0)
     return -1;
 
-  tor_assert(link_cert);
+  if (conn_in_server_mode) {
+    own_link_cert = tor_tls_get_own_cert(conn->tls);
+  }
   tor_assert(id_cert);
 
   certs_cell = certs_cell_new();
 
   /* Start adding certs.  First the link cert or auth1024 cert. */
   if (conn_in_server_mode) {
+    tor_assert_nonfatal(own_link_cert);
     add_x509_cert(certs_cell,
-                  OR_CERT_TYPE_TLS_LINK, link_cert);
+                  OR_CERT_TYPE_TLS_LINK, own_link_cert);
   } else {
+    tor_assert(global_link_cert);
     add_x509_cert(certs_cell,
-                  OR_CERT_TYPE_AUTH_1024, link_cert);
+                  OR_CERT_TYPE_AUTH_1024, global_link_cert);
   }
 
   /* Next the RSA->RSA ID cert */
@@ -2344,6 +2350,7 @@ connection_or_send_certs_cell(or_connection_t *conn)
   connection_or_write_var_cell_to_buf(cell, conn);
   var_cell_free(cell);
   certs_cell_free(certs_cell);
+  tor_x509_cert_free(own_link_cert);
 
   return 0;
 }
@@ -2484,10 +2491,10 @@ connection_or_compute_authenticate_cell_body(or_connection_t *conn,
   memcpy(auth1_getarray_type(auth), authtype_str, 8);
 
   {
-    const tor_x509_cert_t *id_cert=NULL, *link_cert=NULL;
+    const tor_x509_cert_t *id_cert=NULL;
     const common_digests_t *my_digests, *their_digests;
     const uint8_t *my_id, *their_id, *client_id, *server_id;
-    if (tor_tls_get_my_certs(server, &link_cert, &id_cert))
+    if (tor_tls_get_my_certs(server, NULL, &id_cert))
       goto err;
     my_digests = tor_x509_cert_get_id_digests(id_cert);
     their_digests =
@@ -2542,13 +2549,11 @@ connection_or_compute_authenticate_cell_body(or_connection_t *conn,
 
   {
     /* Digest of cert used on TLS link : 32 octets. */
-    const tor_x509_cert_t *cert = NULL;
-    tor_x509_cert_t *freecert = NULL;
+    tor_x509_cert_t *cert = NULL;
     if (server) {
-      tor_tls_get_my_certs(1, &cert, NULL);
+      cert = tor_tls_get_own_cert(conn->tls);
     } else {
-      freecert = tor_tls_get_peer_cert(conn->tls);
-      cert = freecert;
+      cert = tor_tls_get_peer_cert(conn->tls);
     }
     if (!cert) {
       log_warn(LD_OR, "Unable to find cert when making %s data.",
@@ -2559,8 +2564,7 @@ connection_or_compute_authenticate_cell_body(or_connection_t *conn,
     memcpy(auth->scert,
            tor_x509_cert_get_cert_digests(cert)->d[DIGEST_SHA256], 32);
 
-    if (freecert)
-      tor_x509_cert_free(freecert);
+    tor_x509_cert_free(cert);
   }
 
   /* HMAC of clientrandom and serverrandom using master key : 32 octets */
diff --git a/src/test/test_link_handshake.c b/src/test/test_link_handshake.c
index 421f3aaedf..b3e854ef76 100644
--- a/src/test/test_link_handshake.c
+++ b/src/test/test_link_handshake.c
@@ -59,7 +59,7 @@ mock_get_peer_cert(tor_tls_t *tls)
   if (mock_peer_cert_expect_tortls &&
       mock_peer_cert_expect_tortls != tls)
     return NULL;
-  return mock_peer_cert;
+  return tor_x509_cert_dup(mock_peer_cert);
 }
 
 static int mock_send_netinfo_called = 0;
@@ -105,6 +105,14 @@ mock_export_key_material(tor_tls_t *tls, uint8_t *secrets_out,
   return 0;
 }
 
+static tor_x509_cert_t *mock_own_cert = NULL;
+static tor_x509_cert_t *
+mock_get_own_cert(tor_tls_t *tls)
+{
+  (void)tls;
+  return tor_x509_cert_dup(mock_own_cert);
+}
+
 /* Test good certs cells */
 static void
 test_link_handshake_certs_ok(void *arg)
@@ -126,6 +134,7 @@ test_link_handshake_certs_ok(void *arg)
   MOCK(connection_or_write_var_cell_to_buf, mock_write_var_cell);
   MOCK(connection_or_send_netinfo, mock_send_netinfo);
   MOCK(tor_tls_get_peer_cert, mock_get_peer_cert);
+  MOCK(tor_tls_get_own_cert, mock_get_own_cert);
 
   key1 = pk_generate(2);
   key2 = pk_generate(3);
@@ -143,6 +152,12 @@ test_link_handshake_certs_ok(void *arg)
   }
 
   /* c1 has started_here == 1 */
+  {
+    const tor_x509_cert_t *link = NULL;
+    tt_assert(!tor_tls_get_my_certs(1, &link, NULL));
+    mock_own_cert = tor_x509_cert_dup(link);
+  }
+
   c1->base_.state = OR_CONN_STATE_OR_HANDSHAKING_V3;
   c1->link_proto = 3;
   tt_int_op(connection_init_or_handshake_state(c1, 1), ==, 0);
@@ -285,6 +300,9 @@ test_link_handshake_certs_ok(void *arg)
   UNMOCK(connection_or_write_var_cell_to_buf);
   UNMOCK(connection_or_send_netinfo);
   UNMOCK(tor_tls_get_peer_cert);
+  UNMOCK(tor_tls_get_own_cert);
+  tor_x509_cert_free(mock_own_cert);
+  mock_own_cert = NULL;
   memset(c1->identity_digest, 0, sizeof(c1->identity_digest));
   memset(c2->identity_digest, 0, sizeof(c2->identity_digest));
   connection_free_(TO_CONN(c1));
@@ -322,6 +340,7 @@ recv_certs_cleanup(const struct testcase_t *test, void *obj)
   UNMOCK(connection_or_send_netinfo);
   UNMOCK(connection_or_close_for_error);
   UNMOCK(tor_tls_get_peer_cert);
+  UNMOCK(tor_tls_get_own_cert);
 
   if (d) {
     tor_free(d->cell);
@@ -1130,6 +1149,7 @@ authenticate_data_cleanup(const struct testcase_t *test, void *arg)
   (void) test;
   UNMOCK(connection_or_write_var_cell_to_buf);
   UNMOCK(tor_tls_get_peer_cert);
+  UNMOCK(tor_tls_get_own_cert);
   UNMOCK(tor_tls_get_tlssecrets);
   UNMOCK(connection_or_close_for_error);
   UNMOCK(channel_set_circid_type);
@@ -1147,7 +1167,11 @@ authenticate_data_cleanup(const struct testcase_t *test, void *arg)
     crypto_pk_free(d->key2);
     tor_free(d);
   }
+  tor_x509_cert_free(mock_peer_cert);
+  tor_x509_cert_free(mock_own_cert);
   mock_peer_cert = NULL;
+  mock_own_cert = NULL;
+
   return 1;
 }
 
@@ -1161,6 +1185,7 @@ authenticate_data_setup(const struct testcase_t *test)
 
   MOCK(connection_or_write_var_cell_to_buf, mock_write_var_cell);
   MOCK(tor_tls_get_peer_cert, mock_get_peer_cert);
+  MOCK(tor_tls_get_own_cert, mock_get_own_cert);
   MOCK(tor_tls_get_tlssecrets, mock_get_tlssecrets);
   MOCK(connection_or_close_for_error, mock_close_for_err);
   MOCK(channel_set_circid_type, mock_set_circid_type);
@@ -1227,6 +1252,9 @@ authenticate_data_setup(const struct testcase_t *test)
   mock_peer_cert = tor_x509_cert_decode(der, sz);
   tt_assert(mock_peer_cert);
 
+  mock_own_cert = tor_x509_cert_decode(der, sz);
+  tt_assert(mock_own_cert);
+
   /* Make an authenticate cell ... */
   int authtype;
   if (is_ed)