commit e8a1f241783878a242ebb153119af06631fe7cdb Author: Mike Perry mikeperry-git@torproject.org Date: Wed May 15 03:45:03 2019 +0000
Add test to explicitly check state lengths and token counts.
Our other tests tested state lengths against padding packets, and token counts against non-padding packets. This test checks state lengths against non-padding packets (and also padding packets too), and checks token counts against padding packets (and also non-padding packets too).
The next three commits are needed to make this test pass (it found 3 bugs). Yay? --- src/test/test_circuitpadding.c | 180 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 180 insertions(+)
diff --git a/src/test/test_circuitpadding.c b/src/test/test_circuitpadding.c index b19bbcc94..b2ae659a6 100644 --- a/src/test/test_circuitpadding.c +++ b/src/test/test_circuitpadding.c @@ -55,6 +55,7 @@ void test_circuitpadding_conditions(void *arg); void test_circuitpadding_serialize(void *arg); void test_circuitpadding_rtt(void *arg); void test_circuitpadding_tokens(void *arg); +void test_circuitpadding_state_length(void *arg);
static void simulate_single_hop_extend(circuit_t *client, circuit_t *mid_relay, @@ -1644,6 +1645,55 @@ simulate_single_hop_extend(circuit_t *client, circuit_t *mid_relay, }
static circpad_machine_spec_t * +helper_create_length_machine(void) +{ + circpad_machine_spec_t *ret = + tor_malloc_zero(sizeof(circpad_machine_spec_t)); + + /* Start, burst */ + circpad_machine_states_init(ret, 2); + + ret->states[CIRCPAD_STATE_START]. + next_state[CIRCPAD_EVENT_PADDING_SENT] = CIRCPAD_STATE_BURST; + + ret->states[CIRCPAD_STATE_BURST]. + next_state[CIRCPAD_EVENT_PADDING_SENT] = CIRCPAD_STATE_BURST; + + ret->states[CIRCPAD_STATE_BURST]. + next_state[CIRCPAD_EVENT_LENGTH_COUNT] = CIRCPAD_STATE_END; + + ret->states[CIRCPAD_STATE_BURST]. + next_state[CIRCPAD_EVENT_BINS_EMPTY] = CIRCPAD_STATE_END; + + /* No token removal.. end via state_length only */ + ret->states[CIRCPAD_STATE_BURST].token_removal = + CIRCPAD_TOKEN_REMOVAL_NONE; + + /* Let's have this one end after 12 packets */ + ret->states[CIRCPAD_STATE_BURST].length_dist.type = CIRCPAD_DIST_UNIFORM; + ret->states[CIRCPAD_STATE_BURST].length_dist.param1 = 12; + ret->states[CIRCPAD_STATE_BURST].length_dist.param2 = 13; + ret->states[CIRCPAD_STATE_BURST].max_length = 12; + + ret->states[CIRCPAD_STATE_BURST].histogram_len = 4; + + ret->states[CIRCPAD_STATE_BURST].histogram_edges[0] = 0; + ret->states[CIRCPAD_STATE_BURST].histogram_edges[1] = 1; + ret->states[CIRCPAD_STATE_BURST].histogram_edges[2] = 1000000; + ret->states[CIRCPAD_STATE_BURST].histogram_edges[3] = 10000000; + + ret->states[CIRCPAD_STATE_BURST].histogram[0] = 0; + ret->states[CIRCPAD_STATE_BURST].histogram[1] = 0; + ret->states[CIRCPAD_STATE_BURST].histogram[2] = 6; + + ret->states[CIRCPAD_STATE_BURST].histogram_total_tokens = 6; + ret->states[CIRCPAD_STATE_BURST].use_rtt_estimate = 0; + ret->states[CIRCPAD_STATE_BURST].length_includes_nonpadding = 0; + + return ret; +} + +static circpad_machine_spec_t * helper_create_conditional_machine(void) { circpad_machine_spec_t *ret = @@ -1739,6 +1789,135 @@ helper_create_conditional_machines(void) }
void +test_circuitpadding_state_length(void *arg) +{ + /** + * Test plan: + * * Explicitly test that with no token removal enabled, we hit + * the state length limit due to either padding, or non-padding. + * * Repeat test with an arbitrary token removal strategy, and + * verify that if we run out of tokens due to padding before we + * hit the state length, we still go to state end (all our + * token removal tests only test nonpadding token removal). + */ + int64_t actual_mocked_monotime_start; + (void)arg; + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + MOCK(circpad_send_command_to_hop, circpad_send_command_to_hop_mock); + + nodes_init(); + dummy_channel.cmux = circuitmux_alloc(); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, + &dummy_channel)); + client_side = TO_CIRCUIT(origin_circuit_new()); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + monotime_init(); + monotime_enable_test_mocking(); + actual_mocked_monotime_start = MONOTIME_MOCK_START; + monotime_set_mock_time_nsec(actual_mocked_monotime_start); + monotime_coarse_set_mock_time_nsec(actual_mocked_monotime_start); + curr_mocked_time = actual_mocked_monotime_start; + + /* This is needed so that we are not considered to be dormant */ + note_user_activity(20); + + timers_initialize(); + circpad_machine_spec_t *client_machine = + helper_create_length_machine(); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + MOCK(node_get_by_id, + node_get_by_id_mock); + + client_side->padding_machine[0] = client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + circpad_machine_runtime_t *mi = client_side->padding_info[0]; + + circpad_cell_event_padding_sent(client_side); + tt_int_op(mi->state_length, OP_EQ, 12); + tt_ptr_op(mi->histogram, OP_EQ, NULL); + + /* Verify that non-padding does not change our state length */ + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->state_length, OP_EQ, 12); + + /* verify that sending padding changes our state length */ + for (uint64_t i = mi->state_length-1; i > 0; i--) { + circpad_send_padding_cell_for_callback(mi); + tt_int_op(mi->state_length, OP_EQ, i); + } + circpad_send_padding_cell_for_callback(mi); + + tt_int_op(mi->state_length, OP_EQ, -1); + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_END); + + /* Restart machine */ + mi->current_state = CIRCPAD_STATE_START; + + /* Now, count nonpadding as part of the state length */ + client_machine->states[CIRCPAD_STATE_BURST].length_includes_nonpadding = 1; + + circpad_cell_event_padding_sent(client_side); + tt_int_op(mi->state_length, OP_EQ, 12); + + /* Verify that non-padding does change our state length now */ + for (uint64_t i = mi->state_length-1; i > 0; i--) { + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->state_length, OP_EQ, i); + } + + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->state_length, OP_EQ, -1); + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_END); + + /* Now, just test token removal when we send padding */ + client_machine->states[CIRCPAD_STATE_BURST].token_removal = + CIRCPAD_TOKEN_REMOVAL_EXACT; + + /* Restart machine */ + mi->current_state = CIRCPAD_STATE_START; + circpad_cell_event_padding_sent(client_side); + tt_int_op(mi->state_length, OP_EQ, 12); + tt_ptr_op(mi->histogram, OP_NE, NULL); + tt_int_op(mi->chosen_bin, OP_EQ, 2); + + /* verify that sending padding changes our state length and + * our histogram now */ + for (uint32_t i = mi->histogram[2]-1; i > 0; i--) { + circpad_send_padding_cell_for_callback(mi); + tt_int_op(mi->chosen_bin, OP_EQ, 2); + tt_int_op(mi->histogram[2], OP_EQ, i); + } + + tt_int_op(mi->state_length, OP_EQ, 7); + tt_int_op(mi->histogram[2], OP_EQ, 1); + + circpad_send_padding_cell_for_callback(mi); + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_END); + + done: + tor_free(client_machine->states); + tor_free(client_machine); + + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + free_fake_orcirc(relay_side); + + circuitmux_detach_all_circuits(dummy_channel.cmux, NULL); + circuitmux_free(dummy_channel.cmux); + timers_shutdown(); + monotime_disable_test_mocking(); + UNMOCK(circuit_package_relay_cell); + UNMOCK(circuitmux_attach_circuit); + UNMOCK(node_get_by_id); + + return; +} + +void test_circuitpadding_conditions(void *arg) { /** @@ -2556,6 +2735,7 @@ test_circuitpadding_reduce_disable(void *arg)
struct testcase_t circuitpadding_tests[] = { TEST_CIRCUITPADDING(circuitpadding_tokens, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_state_length, TT_FORK), TEST_CIRCUITPADDING(circuitpadding_negotiation, TT_FORK), TEST_CIRCUITPADDING(circuitpadding_wronghop, TT_FORK), /** Disabled unstable test until #29298 is implemented (see #29122) */