tests: Implement unit tests for SENDME v1

Part of #26288

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

1 files changed, 223 insertions, 0 deletions

diff --git a/src/test/test_sendme.c b/src/test/test_sendme.c
new file mode 100644
index 0000000000..ad6aac6c0c
--- /dev/null
+++ b/src/test/test_sendme.c
@@ -0,0 +1,223 @@
+/* Copyright (c) 2014-2019, The Tor Project, Inc. */
+/* See LICENSE for licensing information */
+
+/* Unit tests for handling different kinds of relay cell */
+
+#define CIRCUITLIST_PRIVATE
+#define NETWORKSTATUS_PRIVATE
+#define SENDME_PRIVATE
+
+#include "core/or/circuit_st.h"
+#include "core/or/or_circuit_st.h"
+#include "core/or/origin_circuit_st.h"
+#include "core/or/circuitlist.h"
+#include "core/or/sendme.h"
+
+#include "feature/nodelist/networkstatus.h"
+#include "feature/nodelist/networkstatus_st.h"
+
+#include "test/test.h"
+#include "test/log_test_helpers.h"
+
+static void
+setup_mock_consensus(void)
+{
+  current_md_consensus = current_ns_consensus =
+    tor_malloc_zero(sizeof(networkstatus_t));
+  current_md_consensus->net_params = smartlist_new();
+  current_md_consensus->routerstatus_list = smartlist_new();
+}
+
+static void
+free_mock_consensus(void)
+{
+  SMARTLIST_FOREACH(current_md_consensus->routerstatus_list, void *, r,
+                    tor_free(r));
+  smartlist_free(current_md_consensus->routerstatus_list);
+  smartlist_free(current_ns_consensus->net_params);
+  tor_free(current_ns_consensus);
+}
+
+static void
+test_v1_note_digest(void *arg)
+{
+  or_circuit_t *or_circ = NULL;
+  origin_circuit_t *orig_circ = NULL;
+  circuit_t *circ = NULL;
+
+  (void) arg;
+
+  /* Create our dummy circuits. */
+  orig_circ = origin_circuit_new();
+  tt_assert(orig_circ);
+  or_circ = or_circuit_new(1, NULL);
+
+  /* Start by pointing to the origin circuit. */
+  circ = TO_CIRCUIT(orig_circ);
+  circ->purpose = CIRCUIT_PURPOSE_S_REND_JOINED;
+
+  /* We should never note SENDME digest on origin circuit. */
+  sendme_note_cell_digest(circ);
+  tt_assert(!circ->sendme_last_digests);
+  /* We do not need the origin circuit for now. */
+  orig_circ = NULL;
+  circuit_free_(circ);
+  /* Points it to the OR circuit now. */
+  circ = TO_CIRCUIT(or_circ);
+  or_circ->crypto.sendme_digest = crypto_digest_new();
+
+  /* The package window has to be a multiple of CIRCWINDOW_INCREMENT minus 1
+   * in order to catched the CIRCWINDOW_INCREMENT-nth cell. Try something that
+   * shouldn't be noted. */
+  circ->package_window = CIRCWINDOW_INCREMENT;
+  sendme_note_cell_digest(circ);
+  tt_assert(!circ->sendme_last_digests);
+
+  /* This should work now. Package window at CIRCWINDOW_INCREMENT + 1. */
+  circ->package_window++;
+  sendme_note_cell_digest(circ);
+  tt_assert(circ->sendme_last_digests);
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 1);
+
+  /* Next cell in the package window shouldn't do anything. */
+  circ->package_window++;
+  sendme_note_cell_digest(circ);
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 1);
+
+  /* The next CIRCWINDOW_INCREMENT should add one more digest. */
+  circ->package_window = (CIRCWINDOW_INCREMENT * 2) + 1;
+  sendme_note_cell_digest(circ);
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 2);
+
+ done:
+  circuit_free_(circ);
+}
+
+static void
+test_v1_consensus_params(void *arg)
+{
+  (void) arg;
+
+  setup_mock_consensus();
+  tt_assert(current_md_consensus);
+
+  /* Both zeroes. */
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_emit_min_version=0");
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_accept_min_version=0");
+  tt_int_op(get_emit_min_version(), OP_EQ, 0);
+  tt_int_op(get_accept_min_version(), OP_EQ, 0);
+  smartlist_clear(current_md_consensus->net_params);
+
+  /* Both ones. */
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_emit_min_version=1");
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_accept_min_version=1");
+  tt_int_op(get_emit_min_version(), OP_EQ, 1);
+  tt_int_op(get_accept_min_version(), OP_EQ, 1);
+  smartlist_clear(current_md_consensus->net_params);
+
+  /* Different values from each other. */
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_emit_min_version=1");
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_accept_min_version=0");
+  tt_int_op(get_emit_min_version(), OP_EQ, 1);
+  tt_int_op(get_accept_min_version(), OP_EQ, 0);
+  smartlist_clear(current_md_consensus->net_params);
+
+  /* Validate is the cell version is coherent with our internal default value
+   * and the one in the consensus. */
+  smartlist_add(current_md_consensus->net_params,
+                (void *) "sendme_accept_min_version=1");
+  /* Minimum acceptable value is 1. */
+  tt_int_op(cell_version_is_valid(1), OP_EQ, true);
+  /* Minimum acceptable value is 1 so a cell version of 0 is refused. */
+  tt_int_op(cell_version_is_valid(0), OP_EQ, false);
+
+ done:
+  free_mock_consensus();
+}
+
+static void
+test_v1_build_cell(void *arg)
+{
+  uint8_t payload[RELAY_PAYLOAD_SIZE];
+  ssize_t ret;
+  crypto_digest_t *cell_digest = NULL;
+  or_circuit_t *or_circ = NULL;
+  circuit_t *circ = NULL;
+
+  (void) arg;
+
+  or_circ = or_circuit_new(1, NULL);
+  circ = TO_CIRCUIT(or_circ);
+
+  cell_digest = crypto_digest_new();
+  crypto_digest_add_bytes(cell_digest, "AAAA", 4);
+  tt_assert(cell_digest);
+
+  /* SENDME v1 payload is 7 bytes. See spec. */
+  ret = build_cell_payload_v1(cell_digest, payload);
+  tt_int_op(ret, OP_EQ, 7);
+
+  /* Validation. */
+
+  /* An empty payload means SENDME version 0 thus valid. */
+  tt_int_op(sendme_is_valid(circ, payload, 0), OP_EQ, true);
+
+  /* An unparseable cell means invalid. */
+  setup_full_capture_of_logs(LOG_INFO);
+  tt_int_op(sendme_is_valid(circ, (const uint8_t *) "A", 1), OP_EQ, false);
+  expect_log_msg_containing("Unparseable SENDME cell received. "
+                            "Closing circuit.");
+  teardown_capture_of_logs();
+
+  /* No cell digest recorded for this. */
+  setup_full_capture_of_logs(LOG_INFO);
+  tt_int_op(sendme_is_valid(circ, payload, sizeof(payload)), OP_EQ, false);
+  expect_log_msg_containing("We received a SENDME but we have no cell digests "
+                            "to match. Closing circuit.");
+  teardown_capture_of_logs();
+
+  /* Note the wrong digest in the circuit, cell should fail validation. */
+  or_circ->crypto.sendme_digest = crypto_digest_new();
+  circ->package_window = CIRCWINDOW_INCREMENT + 1;
+  sendme_note_cell_digest(circ);
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 1);
+  setup_full_capture_of_logs(LOG_INFO);
+  tt_int_op(sendme_is_valid(circ, payload, sizeof(payload)), OP_EQ, false);
+  /* After a validation, the last digests is always popped out. */
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 0);
+  expect_log_msg_containing("SENDME v1 cell digest do not match.");
+  teardown_capture_of_logs();
+
+  /* Cleanup */
+  crypto_digest_free(or_circ->crypto.sendme_digest);
+
+  /* Record the cell digest into the circuit, cell should validate. */
+  or_circ->crypto.sendme_digest = crypto_digest_dup(cell_digest);
+  circ->package_window = CIRCWINDOW_INCREMENT + 1;
+  sendme_note_cell_digest(circ);
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 1);
+  tt_int_op(sendme_is_valid(circ, payload, sizeof(payload)), OP_EQ, true);
+  /* After a validation, the last digests is always popped out. */
+  tt_int_op(smartlist_len(circ->sendme_last_digests), OP_EQ, 0);
+
+ done:
+  crypto_digest_free(cell_digest);
+  circuit_free_(circ);
+}
+
+struct testcase_t sendme_tests[] = {
+  { "v1_note_digest", test_v1_note_digest, TT_FORK,
+    NULL, NULL },
+  { "v1_consensus_params", test_v1_consensus_params, TT_FORK,
+    NULL, NULL },
+  { "v1_build_cell", test_v1_build_cell, TT_FORK,
+    NULL, NULL },
+
+  END_OF_TESTCASES
+};