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Diffstat (limited to 'src/test/test_circuitpadding.c')
| -rw-r--r-- | src/test/test_circuitpadding.c | 3147 |
1 files changed, 3147 insertions, 0 deletions
diff --git a/src/test/test_circuitpadding.c b/src/test/test_circuitpadding.c new file mode 100644 index 0000000000..cfb24c032c --- /dev/null +++ b/src/test/test_circuitpadding.c @@ -0,0 +1,3147 @@ +#define CHANNEL_OBJECT_PRIVATE +#define TOR_TIMERS_PRIVATE +#define CIRCUITPADDING_PRIVATE +#define CIRCUITPADDING_MACHINES_PRIVATE +#define NETWORKSTATUS_PRIVATE +#define CRYPT_PATH_PRIVATE +#define RELAY_PRIVATE + +#include "core/or/or.h" +#include "test/test.h" +#include "test/log_test_helpers.h" +#include "lib/testsupport/testsupport.h" +#include "core/or/connection_or.h" +#include "core/or/channel.h" +#include "core/or/channeltls.h" +#include "core/or/crypt_path.h" +#include <event.h> +#include "lib/evloop/compat_libevent.h" +#include "lib/time/compat_time.h" +#include "lib/defs/time.h" +#include "core/or/relay.h" +#include "core/or/circuitlist.h" +#include "core/or/circuitbuild.h" +#include "core/or/circuitpadding.h" +#include "core/or/circuitpadding_machines.h" +#include "core/mainloop/netstatus.h" +#include "core/crypto/relay_crypto.h" +#include "core/or/protover.h" +#include "feature/nodelist/nodelist.h" +#include "app/config/config.h" + +#include "feature/nodelist/routerstatus_st.h" +#include "feature/nodelist/networkstatus_st.h" +#include "feature/nodelist/node_st.h" +#include "core/or/cell_st.h" +#include "core/or/crypt_path_st.h" +#include "core/or/or_circuit_st.h" +#include "core/or/origin_circuit_st.h" + +#include "test/fakecircs.h" +#include "test/rng_test_helpers.h" + +/* Start our monotime mocking at 1 second past whatever monotime_init() + * thought the actual wall clock time was, for platforms with bad resolution + * and weird timevalues during monotime_init() before mocking. */ +#define MONOTIME_MOCK_START (monotime_absolute_nsec()+\ + TOR_NSEC_PER_USEC*TOR_USEC_PER_SEC) + +extern smartlist_t *connection_array; +void circuit_expire_old_circuits_clientside(void); + +circid_t get_unique_circ_id_by_chan(channel_t *chan); +void helper_create_basic_machine(void); +static void helper_create_conditional_machines(void); + +channel_t *new_fake_channel(void); +void test_circuitpadding_negotiation(void *arg); +void test_circuitpadding_wronghop(void *arg); +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, + int padding); +void free_fake_origin_circuit(origin_circuit_t *circ); + +static int deliver_negotiated = 1; +static int64_t curr_mocked_time; + +static node_t padding_node; +static node_t non_padding_node; + +static channel_t dummy_channel; +static circpad_machine_spec_t circ_client_machine; + +static void +timers_advance_and_run(int64_t msec_update) +{ + curr_mocked_time += msec_update*TOR_NSEC_PER_MSEC; + monotime_coarse_set_mock_time_nsec(curr_mocked_time); + monotime_set_mock_time_nsec(curr_mocked_time); + timers_run_pending(); +} + +static void +nodes_init(void) +{ + padding_node.rs = tor_malloc_zero(sizeof(routerstatus_t)); + padding_node.rs->pv.supports_hs_setup_padding = 1; + + non_padding_node.rs = tor_malloc_zero(sizeof(routerstatus_t)); + non_padding_node.rs->pv.supports_hs_setup_padding = 0; +} + +static void +nodes_free(void) +{ + tor_free(padding_node.rs); + + tor_free(non_padding_node.rs); +} + +static const node_t * +node_get_by_id_mock(const char *identity_digest) +{ + if (identity_digest[0] == 1) { + return &padding_node; + } else if (identity_digest[0] == 0) { + return &non_padding_node; + } + + return NULL; +} + +static const node_t * +circuit_get_nth_node_mock(origin_circuit_t *circ, int hop) +{ + (void) circ; + (void) hop; + + return &padding_node; +} + +void +free_fake_origin_circuit(origin_circuit_t *circ) +{ + circpad_circuit_free_all_machineinfos(TO_CIRCUIT(circ)); + circuit_clear_cpath(circ); + tor_free(circ); +} + +void dummy_nop_timer(void); + +//static int dont_stop_libevent = 0; + +static circuit_t *client_side; +static circuit_t *relay_side; + +static int n_client_cells = 0; +static int n_relay_cells = 0; + +static int +circuit_package_relay_cell_mock(cell_t *cell, circuit_t *circ, + cell_direction_t cell_direction, + crypt_path_t *layer_hint, streamid_t on_stream, + const char *filename, int lineno); + +static void +circuitmux_attach_circuit_mock(circuitmux_t *cmux, circuit_t *circ, + cell_direction_t direction); + +static void +circuitmux_attach_circuit_mock(circuitmux_t *cmux, circuit_t *circ, + cell_direction_t direction) +{ + (void)cmux; + (void)circ; + (void)direction; + + return; +} + +static int +circuit_package_relay_cell_mock(cell_t *cell, circuit_t *circ, + cell_direction_t cell_direction, + crypt_path_t *layer_hint, streamid_t on_stream, + const char *filename, int lineno) +{ + (void)cell; (void)on_stream; (void)filename; (void)lineno; + + if (circ == client_side) { + if (cell->payload[0] == RELAY_COMMAND_PADDING_NEGOTIATE) { + // Deliver to relay + circpad_handle_padding_negotiate(relay_side, cell); + } else { + + int is_target_hop = circpad_padding_is_from_expected_hop(circ, + layer_hint); + tt_int_op(cell_direction, OP_EQ, CELL_DIRECTION_OUT); + tt_int_op(is_target_hop, OP_EQ, 1); + + // No need to pretend a padding cell was sent: This event is + // now emitted internally when the circuitpadding code sends them. + //circpad_cell_event_padding_sent(client_side); + + // Receive padding cell at middle + circpad_deliver_recognized_relay_cell_events(relay_side, + cell->payload[0], NULL); + } + n_client_cells++; + } else if (circ == relay_side) { + tt_int_op(cell_direction, OP_EQ, CELL_DIRECTION_IN); + + if (cell->payload[0] == RELAY_COMMAND_PADDING_NEGOTIATED) { + // XXX: blah need right layer_hint.. + if (deliver_negotiated) + circpad_handle_padding_negotiated(client_side, cell, + TO_ORIGIN_CIRCUIT(client_side) + ->cpath->next); + } else if (cell->payload[0] == RELAY_COMMAND_PADDING_NEGOTIATE) { + circpad_handle_padding_negotiate(client_side, cell); + } else { + // No need to pretend a padding cell was sent: This event is + // now emitted internally when the circuitpadding code sends them. + //circpad_cell_event_padding_sent(relay_side); + + // Receive padding cell at client + circpad_deliver_recognized_relay_cell_events(client_side, + cell->payload[0], + TO_ORIGIN_CIRCUIT(client_side)->cpath->next); + } + + n_relay_cells++; + } + + done: + timers_advance_and_run(1); + return 0; +} + +// Test reading and writing padding to strings (or options_t + consensus) +void +test_circuitpadding_serialize(void *arg) +{ + (void)arg; +} + +static signed_error_t +circpad_send_command_to_hop_mock(origin_circuit_t *circ, uint8_t hopnum, + uint8_t relay_command, const uint8_t *payload, + ssize_t payload_len) +{ + (void) circ; + (void) hopnum; + (void) relay_command; + (void) payload; + (void) payload_len; + return 0; +} + +void +test_circuitpadding_rtt(void *arg) +{ + /* Test Plan: + * + * 1. Test RTT measurement server side + * a. test usage of measured RTT + * 2. Test termination of RTT measurement + * a. test non-update of RTT + * 3. Test client side circuit and non-application of RTT.. + */ + circpad_delay_t rtt_estimate; + 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); + testing_enable_reproducible_rng(); + + 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; + + timers_initialize(); + circpad_machines_init(); + helper_create_basic_machine(); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = circpad_circuit_machineinfo_new(client_side, + 0); + + relay_side->padding_machine[0] = &circ_client_machine; + relay_side->padding_info[0] = circpad_circuit_machineinfo_new(client_side,0); + + /* Test 1: Test measuring RTT */ + circpad_cell_event_nonpadding_received(relay_side); + tt_u64_op(relay_side->padding_info[0]->last_received_time_usec, OP_NE, 0); + + timers_advance_and_run(20); + + circpad_cell_event_nonpadding_sent(relay_side); + tt_u64_op(relay_side->padding_info[0]->last_received_time_usec, OP_EQ, 0); + + tt_int_op(relay_side->padding_info[0]->rtt_estimate_usec, OP_GE, 19000); + tt_int_op(relay_side->padding_info[0]->rtt_estimate_usec, OP_LE, 30000); + tt_int_op(circpad_histogram_bin_to_usec(relay_side->padding_info[0], 0), + OP_EQ, + relay_side->padding_info[0]->rtt_estimate_usec+ + circpad_machine_current_state( + relay_side->padding_info[0])->histogram_edges[0]); + + circpad_cell_event_nonpadding_received(relay_side); + circpad_cell_event_nonpadding_received(relay_side); + tt_u64_op(relay_side->padding_info[0]->last_received_time_usec, OP_NE, 0); + timers_advance_and_run(20); + circpad_cell_event_nonpadding_sent(relay_side); + circpad_cell_event_nonpadding_sent(relay_side); + tt_u64_op(relay_side->padding_info[0]->last_received_time_usec, OP_EQ, 0); + + tt_int_op(relay_side->padding_info[0]->rtt_estimate_usec, OP_GE, 20000); + tt_int_op(relay_side->padding_info[0]->rtt_estimate_usec, OP_LE, 21000); + tt_int_op(circpad_histogram_bin_to_usec(relay_side->padding_info[0], 0), + OP_EQ, + relay_side->padding_info[0]->rtt_estimate_usec+ + circpad_machine_current_state( + relay_side->padding_info[0])->histogram_edges[0]); + + /* Test 2: Termination of RTT measurement (from the previous test) */ + tt_int_op(relay_side->padding_info[0]->stop_rtt_update, OP_EQ, 1); + rtt_estimate = relay_side->padding_info[0]->rtt_estimate_usec; + + circpad_cell_event_nonpadding_received(relay_side); + timers_advance_and_run(4); + circpad_cell_event_nonpadding_sent(relay_side); + + tt_int_op(relay_side->padding_info[0]->rtt_estimate_usec, OP_EQ, + rtt_estimate); + tt_u64_op(relay_side->padding_info[0]->last_received_time_usec, OP_EQ, 0); + tt_int_op(relay_side->padding_info[0]->stop_rtt_update, OP_EQ, 1); + tt_int_op(circpad_histogram_bin_to_usec(relay_side->padding_info[0], 0), + OP_EQ, + relay_side->padding_info[0]->rtt_estimate_usec+ + circpad_machine_current_state( + relay_side->padding_info[0])->histogram_edges[0]); + + /* Test 3: Make sure client side machine properly ignores RTT */ + circpad_cell_event_nonpadding_received(client_side); + tt_u64_op(client_side->padding_info[0]->last_received_time_usec, OP_EQ, 0); + + timers_advance_and_run(20); + circpad_cell_event_nonpadding_sent(client_side); + tt_u64_op(client_side->padding_info[0]->last_received_time_usec, OP_EQ, 0); + + tt_int_op(client_side->padding_info[0]->rtt_estimate_usec, OP_EQ, 0); + tt_int_op(circpad_histogram_bin_to_usec(client_side->padding_info[0], 0), + OP_NE, client_side->padding_info[0]->rtt_estimate_usec); + tt_int_op(circpad_histogram_bin_to_usec(client_side->padding_info[0], 0), + OP_EQ, + circpad_machine_current_state( + client_side->padding_info[0])->histogram_edges[0]); + done: + free_fake_orcirc(TO_OR_CIRCUIT(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); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); + + return; +} + +void +helper_create_basic_machine(void) +{ + /* Start, burst */ + circpad_machine_states_init(&circ_client_machine, 2); + + circ_client_machine.name = "basic"; + + circ_client_machine.states[CIRCPAD_STATE_START]. + next_state[CIRCPAD_EVENT_NONPADDING_RECV] = CIRCPAD_STATE_BURST; + circ_client_machine.states[CIRCPAD_STATE_START].use_rtt_estimate = 1; + + circ_client_machine.states[CIRCPAD_STATE_BURST]. + next_state[CIRCPAD_EVENT_PADDING_RECV] = CIRCPAD_STATE_BURST; + circ_client_machine.states[CIRCPAD_STATE_BURST]. + next_state[CIRCPAD_EVENT_NONPADDING_RECV] = CIRCPAD_STATE_BURST; + + circ_client_machine.states[CIRCPAD_STATE_BURST]. + next_state[CIRCPAD_EVENT_NONPADDING_SENT] = CIRCPAD_STATE_CANCEL; + + circ_client_machine.states[CIRCPAD_STATE_BURST].token_removal = + CIRCPAD_TOKEN_REMOVAL_HIGHER; + + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_len = 5; + + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[0] = 500; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[1] = 2500; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[2] = 5000; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[3] = 10000; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[4] = 20000; + + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram[0] = 1; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram[1] = 0; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram[2] = 2; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram[3] = 2; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram[4] = 2; + + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_total_tokens = 7; + circ_client_machine.states[CIRCPAD_STATE_BURST].use_rtt_estimate = 1; + + return; +} + +#define BIG_HISTOGRAM_LEN 10 + +/** Setup a machine with a big histogram */ +static void +helper_create_machine_with_big_histogram(circpad_removal_t removal_strategy) +{ + const int tokens_per_bin = 2; + + /* Start, burst */ + circpad_machine_states_init(&circ_client_machine, 2); + + circpad_state_t *burst_state = + &circ_client_machine.states[CIRCPAD_STATE_BURST]; + + circ_client_machine.states[CIRCPAD_STATE_START]. + next_state[CIRCPAD_EVENT_NONPADDING_RECV] = CIRCPAD_STATE_BURST; + + burst_state->next_state[CIRCPAD_EVENT_PADDING_RECV] = CIRCPAD_STATE_BURST; + burst_state->next_state[CIRCPAD_EVENT_NONPADDING_RECV] =CIRCPAD_STATE_BURST; + + burst_state->next_state[CIRCPAD_EVENT_NONPADDING_SENT] =CIRCPAD_STATE_CANCEL; + + burst_state->token_removal = CIRCPAD_TOKEN_REMOVAL_HIGHER; + + burst_state->histogram_len = BIG_HISTOGRAM_LEN; + + int n_tokens = 0; + int i; + for (i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + burst_state->histogram[i] = tokens_per_bin; + n_tokens += tokens_per_bin; + } + + burst_state->histogram_edges[0] = 0; + burst_state->histogram_edges[1] = 1; + burst_state->histogram_edges[2] = 7; + burst_state->histogram_edges[3] = 15; + burst_state->histogram_edges[4] = 31; + burst_state->histogram_edges[5] = 62; + burst_state->histogram_edges[6] = 125; + burst_state->histogram_edges[7] = 250; + burst_state->histogram_edges[8] = 500; + burst_state->histogram_edges[9] = 1000; + + burst_state->histogram_total_tokens = n_tokens; + burst_state->length_dist.type = CIRCPAD_DIST_UNIFORM; + burst_state->length_dist.param1 = n_tokens; + burst_state->length_dist.param2 = n_tokens; + burst_state->max_length = n_tokens; + burst_state->length_includes_nonpadding = 1; + burst_state->use_rtt_estimate = 0; + burst_state->token_removal = removal_strategy; +} + +static circpad_decision_t +circpad_machine_schedule_padding_mock(circpad_machine_runtime_t *mi) +{ + (void)mi; + return 0; +} + +static uint64_t +mock_monotime_absolute_usec(void) +{ + return 100; +} + +/** Test higher token removal strategy by bin */ +static void +test_circuitpadding_token_removal_higher(void *arg) +{ + circpad_machine_runtime_t *mi; + (void)arg; + + /* Mock it up */ + MOCK(monotime_absolute_usec, mock_monotime_absolute_usec); + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + /* Setup test environment (time etc.) */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + monotime_enable_test_mocking(); + + /* Create test machine */ + helper_create_machine_with_big_histogram(CIRCPAD_TOKEN_REMOVAL_HIGHER); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + + /* move the machine to the right state */ + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + /* Get the machine and setup tokens */ + mi = client_side->padding_info[0]; + tt_assert(mi); + + /*************************************************************************/ + + uint64_t current_time = monotime_absolute_usec(); + + /* Test left boundaries of each histogram bin: */ + const circpad_delay_t bin_left_bounds[] = + {0, 1, 7, 15, 31, 62, 125, 250, 500, 1000, CIRCPAD_DELAY_INFINITE}; + for (int i = 0; i <= BIG_HISTOGRAM_LEN ; i++) { + tt_uint_op(bin_left_bounds[i], OP_EQ, + circpad_histogram_bin_to_usec(mi, i)); + } + + /* Test right boundaries of each histogram bin: */ + const circpad_delay_t bin_right_bounds[] = + {0, 6, 14, 30, 61, 124, 249, 499, 999, CIRCPAD_DELAY_INFINITE-1}; + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_uint_op(bin_right_bounds[i], OP_EQ, + histogram_get_bin_upper_bound(mi, i)); + } + + /* Check that all bins have two tokens right now */ + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* This is the right order to remove tokens from this histogram. That is, we + * first remove tokens from the 4th bin since 57 usec is nearest to the 4th + * bin midpoint (31 + (62-31)/2 == 46). Then we remove from the 3rd bin for + * the same reason, then from the 5th, etc. */ + const int bin_removal_order[] = {4, 5, 6, 7, 8}; + unsigned i; + + /* Remove all tokens from all bins apart from the infinity bin */ + for (i = 0; i < sizeof(bin_removal_order)/sizeof(int) ; i++) { + int bin_to_remove = bin_removal_order[i]; + log_debug(LD_GENERAL, "Testing that %d attempt removes %d bin", + i, bin_to_remove); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 2); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 1); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + /* Test that we cleaned out this bin. Don't do this in the case of the last + bin since the tokens will get refilled */ + if (i != BIG_HISTOGRAM_LEN - 2) { + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 0); + } + } + + /* Check that all lower bins are not touched */ + for (i=0; i < 4 ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* Test below the lowest bin, for coverage */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[0] = 100; + mi->padding_scheduled_at_usec = current_time; + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[0], OP_EQ, 1); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + monotime_disable_test_mocking(); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); +} + +/** Test lower token removal strategy by bin */ +static void +test_circuitpadding_token_removal_lower(void *arg) +{ + circpad_machine_runtime_t *mi; + (void)arg; + + /* Mock it up */ + MOCK(monotime_absolute_usec, mock_monotime_absolute_usec); + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + /* Setup test environment (time etc.) */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + monotime_enable_test_mocking(); + + /* Create test machine */ + helper_create_machine_with_big_histogram(CIRCPAD_TOKEN_REMOVAL_LOWER); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + + /* move the machine to the right state */ + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + /* Get the machine and setup tokens */ + mi = client_side->padding_info[0]; + tt_assert(mi); + + /*************************************************************************/ + + uint64_t current_time = monotime_absolute_usec(); + + /* Test left boundaries of each histogram bin: */ + const circpad_delay_t bin_left_bounds[] = + {0, 1, 7, 15, 31, 62, 125, 250, 500, 1000, CIRCPAD_DELAY_INFINITE}; + for (int i = 0; i <= BIG_HISTOGRAM_LEN ; i++) { + tt_uint_op(bin_left_bounds[i], OP_EQ, + circpad_histogram_bin_to_usec(mi, i)); + } + + /* Check that all bins have two tokens right now */ + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* This is the right order to remove tokens from this histogram. That is, we + * first remove tokens from the 4th bin since 57 usec is nearest to the 4th + * bin midpoint (31 + (62-31)/2 == 46). Then we remove from the 3rd bin for + * the same reason, then from the 5th, etc. */ + const int bin_removal_order[] = {4, 3, 2, 1, 0}; + unsigned i; + + /* Remove all tokens from all bins apart from the infinity bin */ + for (i = 0; i < sizeof(bin_removal_order)/sizeof(int) ; i++) { + int bin_to_remove = bin_removal_order[i]; + log_debug(LD_GENERAL, "Testing that %d attempt removes %d bin", + i, bin_to_remove); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 2); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 1); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + /* Test that we cleaned out this bin. Don't do this in the case of the last + bin since the tokens will get refilled */ + if (i != BIG_HISTOGRAM_LEN - 2) { + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 0); + } + } + + /* Check that all higher bins are untouched */ + for (i = 5; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* Test above the highest bin, for coverage */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + circ_client_machine.states[CIRCPAD_STATE_BURST]. + histogram_edges[BIG_HISTOGRAM_LEN-2] = 100; + mi->padding_scheduled_at_usec = current_time - 29202; + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[BIG_HISTOGRAM_LEN-2], OP_EQ, 1); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + monotime_disable_test_mocking(); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); +} + +/** Test closest token removal strategy by bin */ +static void +test_circuitpadding_closest_token_removal(void *arg) +{ + circpad_machine_runtime_t *mi; + (void)arg; + + /* Mock it up */ + MOCK(monotime_absolute_usec, mock_monotime_absolute_usec); + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + /* Setup test environment (time etc.) */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + monotime_enable_test_mocking(); + + /* Create test machine */ + helper_create_machine_with_big_histogram(CIRCPAD_TOKEN_REMOVAL_CLOSEST); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + + /* move the machine to the right state */ + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + /* Get the machine and setup tokens */ + mi = client_side->padding_info[0]; + tt_assert(mi); + + /*************************************************************************/ + + uint64_t current_time = monotime_absolute_usec(); + + /* Test left boundaries of each histogram bin: */ + const circpad_delay_t bin_left_bounds[] = + {0, 1, 7, 15, 31, 62, 125, 250, 500, 1000, CIRCPAD_DELAY_INFINITE}; + for (int i = 0; i <= BIG_HISTOGRAM_LEN ; i++) { + tt_uint_op(bin_left_bounds[i], OP_EQ, + circpad_histogram_bin_to_usec(mi, i)); + } + + /* Check that all bins have two tokens right now */ + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* This is the right order to remove tokens from this histogram. That is, we + * first remove tokens from the 4th bin since 57 usec is nearest to the 4th + * bin midpoint (31 + (62-31)/2 == 46). Then we remove from the 3rd bin for + * the same reason, then from the 5th, etc. */ + const int bin_removal_order[] = {4, 3, 5, 2, 6, 1, 7, 0, 8, 9}; + + /* Remove all tokens from all bins apart from the infinity bin */ + for (int i = 0; i < BIG_HISTOGRAM_LEN-1 ; i++) { + int bin_to_remove = bin_removal_order[i]; + log_debug(LD_GENERAL, "Testing that %d attempt removes %d bin", + i, bin_to_remove); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 2); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 1); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + /* Test that we cleaned out this bin. Don't do this in the case of the last + bin since the tokens will get refilled */ + if (i != BIG_HISTOGRAM_LEN - 2) { + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 0); + } + } + + /* Check that all bins have been refilled */ + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* Test below the lowest bin, for coverage */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[0] = 100; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[1] = 101; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[2] = 120; + mi->padding_scheduled_at_usec = current_time - 102; + mi->histogram[0] = 0; + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[1], OP_EQ, 1); + + /* Test above the highest bin, for coverage */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + mi->padding_scheduled_at_usec = current_time - 29202; + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[BIG_HISTOGRAM_LEN-2], OP_EQ, 1); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + monotime_disable_test_mocking(); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); +} + +/** Test closest token removal strategy with usec */ +static void +test_circuitpadding_closest_token_removal_usec(void *arg) +{ + circpad_machine_runtime_t *mi; + (void)arg; + + /* Mock it up */ + MOCK(monotime_absolute_usec, mock_monotime_absolute_usec); + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + /* Setup test environment (time etc.) */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + monotime_enable_test_mocking(); + + /* Create test machine */ + helper_create_machine_with_big_histogram(CIRCPAD_TOKEN_REMOVAL_CLOSEST_USEC); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + + /* move the machine to the right state */ + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + /* Get the machine and setup tokens */ + mi = client_side->padding_info[0]; + tt_assert(mi); + + /*************************************************************************/ + + uint64_t current_time = monotime_absolute_usec(); + + /* Test left boundaries of each histogram bin: */ + const circpad_delay_t bin_left_bounds[] = + {0, 1, 7, 15, 31, 62, 125, 250, 500, 1000, CIRCPAD_DELAY_INFINITE}; + for (int i = 0; i <= BIG_HISTOGRAM_LEN ; i++) { + tt_uint_op(bin_left_bounds[i], OP_EQ, + circpad_histogram_bin_to_usec(mi, i)); + } + + /* XXX we want to test remove_token_exact and + circpad_machine_remove_closest_token() with usec */ + + /* Check that all bins have two tokens right now */ + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* This is the right order to remove tokens from this histogram. That is, we + * first remove tokens from the 4th bin since 57 usec is nearest to the 4th + * bin midpoint (31 + (62-31)/2 == 46). Then we remove from the 3rd bin for + * the same reason, then from the 5th, etc. */ + const int bin_removal_order[] = {4, 3, 5, 2, 1, 0, 6, 7, 8, 9}; + + /* Remove all tokens from all bins apart from the infinity bin */ + for (int i = 0; i < BIG_HISTOGRAM_LEN-1 ; i++) { + int bin_to_remove = bin_removal_order[i]; + log_debug(LD_GENERAL, "Testing that %d attempt removes %d bin", + i, bin_to_remove); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 2); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 1); + + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + + /* Test that we cleaned out this bin. Don't do this in the case of the last + bin since the tokens will get refilled */ + if (i != BIG_HISTOGRAM_LEN - 2) { + tt_int_op(mi->histogram[bin_to_remove], OP_EQ, 0); + } + } + + /* Check that all bins have been refilled */ + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + + /* Test below the lowest bin, for coverage */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[0] = 100; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[1] = 101; + circ_client_machine.states[CIRCPAD_STATE_BURST].histogram_edges[2] = 120; + mi->padding_scheduled_at_usec = current_time - 102; + mi->histogram[0] = 0; + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[1], OP_EQ, 1); + + /* Test above the highest bin, for coverage */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + circ_client_machine.states[CIRCPAD_STATE_BURST]. + histogram_edges[BIG_HISTOGRAM_LEN-2] = 100; + mi->padding_scheduled_at_usec = current_time - 29202; + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[BIG_HISTOGRAM_LEN-2], OP_EQ, 1); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + monotime_disable_test_mocking(); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); +} + +/** Test closest token removal strategy with usec */ +static void +test_circuitpadding_token_removal_exact(void *arg) +{ + circpad_machine_runtime_t *mi; + (void)arg; + + /* Mock it up */ + MOCK(monotime_absolute_usec, mock_monotime_absolute_usec); + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + /* Setup test environment (time etc.) */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + monotime_enable_test_mocking(); + + /* Create test machine */ + helper_create_machine_with_big_histogram(CIRCPAD_TOKEN_REMOVAL_EXACT); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + + /* move the machine to the right state */ + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + /* Get the machine and setup tokens */ + mi = client_side->padding_info[0]; + tt_assert(mi); + + /**********************************************************************/ + uint64_t current_time = monotime_absolute_usec(); + + /* Ensure that we will clear out bin #4 with this usec */ + mi->padding_scheduled_at_usec = current_time - 57; + tt_int_op(mi->histogram[4], OP_EQ, 2); + circpad_cell_event_nonpadding_sent(client_side); + mi->padding_scheduled_at_usec = current_time - 57; + tt_int_op(mi->histogram[4], OP_EQ, 1); + circpad_cell_event_nonpadding_sent(client_side); + tt_int_op(mi->histogram[4], OP_EQ, 0); + + /* Ensure that we will not remove any other tokens even tho we try to, since + * this is what the exact strategy dictates */ + mi->padding_scheduled_at_usec = current_time - 57; + circpad_cell_event_nonpadding_sent(client_side); + for (int i = 0; i < BIG_HISTOGRAM_LEN ; i++) { + if (i != 4) { + tt_int_op(mi->histogram[i], OP_EQ, 2); + } + } + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + monotime_disable_test_mocking(); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); +} + +#undef BIG_HISTOGRAM_LEN + +void +test_circuitpadding_tokens(void *arg) +{ + const circpad_state_t *state; + circpad_machine_runtime_t *mi; + int64_t actual_mocked_monotime_start; + (void)arg; + + testing_enable_reproducible_rng(); + + /** Test plan: + * + * 1. Test symmetry between bin_to_usec and usec_to_bin + * a. Test conversion + * b. Test edge transitions (lower, upper) + * 2. Test remove higher on an empty bin + * a. Normal bin + * b. Infinity bin + * c. Bin 0 + * d. No higher + * 3. Test remove lower + * a. Normal bin + * b. Bin 0 + * c. No lower + * 4. Test remove closest + * a. Closest lower + * b. Closest higher + * c. Closest 0 + * d. Closest Infinity + */ + client_side = TO_CIRCUIT(origin_circuit_new()); + 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(); + + helper_create_basic_machine(); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = circpad_circuit_machineinfo_new(client_side, + 0); + + mi = client_side->padding_info[0]; + + // Pretend a non-padding cell was sent + circpad_cell_event_nonpadding_received(client_side); + circpad_cell_event_nonpadding_sent(client_side); + /* We have to save the infinity bin because one inf delay + * could have been chosen when we transition to burst */ + circpad_hist_token_t inf_bin = mi->histogram[4]; + + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + state = circpad_machine_current_state(client_side->padding_info[0]); + + // Test 0: convert bin->usec->bin + // Bin 0+1 have different semantics + for (int bin = 0; bin < 2; bin++) { + circpad_delay_t usec = + circpad_histogram_bin_to_usec(client_side->padding_info[0], bin); + int bin2 = circpad_histogram_usec_to_bin(client_side->padding_info[0], + usec); + tt_int_op(bin, OP_EQ, bin2); + } + for (int bin = 2; bin < state->histogram_len-1; bin++) { + circpad_delay_t usec = + circpad_histogram_bin_to_usec(client_side->padding_info[0], bin); + int bin2 = circpad_histogram_usec_to_bin(client_side->padding_info[0], + usec); + tt_int_op(bin, OP_EQ, bin2); + /* Verify we round down */ + bin2 = circpad_histogram_usec_to_bin(client_side->padding_info[0], + usec+3); + tt_int_op(bin, OP_EQ, bin2); + + bin2 = circpad_histogram_usec_to_bin(client_side->padding_info[0], + usec-1); + tt_int_op(bin, OP_EQ, bin2+1); + } + + // Test 1: converting usec->bin->usec->bin + // Bin 0+1 have different semantics. + for (circpad_delay_t i = 0; i <= state->histogram_edges[0]; i++) { + int bin = circpad_histogram_usec_to_bin(client_side->padding_info[0], + i); + circpad_delay_t usec = + circpad_histogram_bin_to_usec(client_side->padding_info[0], bin); + int bin2 = circpad_histogram_usec_to_bin(client_side->padding_info[0], + usec); + tt_int_op(bin, OP_EQ, bin2); + tt_int_op(i, OP_LE, usec); + } + for (circpad_delay_t i = state->histogram_edges[0]+1; + i <= state->histogram_edges[0] + + state->histogram_edges[state->histogram_len-2]; i++) { + int bin = circpad_histogram_usec_to_bin(client_side->padding_info[0], + i); + circpad_delay_t usec = + circpad_histogram_bin_to_usec(client_side->padding_info[0], bin); + int bin2 = circpad_histogram_usec_to_bin(client_side->padding_info[0], + usec); + tt_int_op(bin, OP_EQ, bin2); + tt_int_op(i, OP_GE, usec); + } + + /* 2.a. Normal higher bin */ + { + tt_int_op(mi->histogram[2], OP_EQ, 2); + tt_int_op(mi->histogram[3], OP_EQ, 2); + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1); + tt_int_op(mi->histogram[3], OP_EQ, 2); + tt_int_op(mi->histogram[2], OP_EQ, 1); + + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1); + tt_int_op(mi->histogram[2], OP_EQ, 0); + + tt_int_op(mi->histogram[3], OP_EQ, 2); + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1); + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1); + tt_int_op(mi->histogram[3], OP_EQ, 0); + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1); + tt_int_op(mi->histogram[3], OP_EQ, 0); + } + + /* 2.b. Higher Infinity bin */ + { + tt_int_op(mi->histogram[4], OP_EQ, inf_bin); + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1); + tt_int_op(mi->histogram[4], OP_EQ, inf_bin); + + /* Test past the infinity bin */ + circpad_machine_remove_higher_token(mi, + circpad_histogram_bin_to_usec(mi, 5)+1000000); + + tt_int_op(mi->histogram[4], OP_EQ, inf_bin); + } + + /* 2.c. Bin 0 */ + { + tt_int_op(mi->histogram[0], OP_EQ, 0); + mi->histogram[0] = 1; + circpad_machine_remove_higher_token(mi, state->histogram_edges[0]/2); + tt_int_op(mi->histogram[0], OP_EQ, 0); + } + + /* Drain the infinity bin and cause a refill */ + while (inf_bin != 0) { + tt_int_op(mi->histogram[4], OP_EQ, inf_bin); + circpad_cell_event_nonpadding_received(client_side); + inf_bin--; + } + + circpad_cell_event_nonpadding_sent(client_side); + + // We should have refilled here. + tt_int_op(mi->histogram[4], OP_EQ, 2); + + /* 3.a. Bin 0 */ + { + tt_int_op(mi->histogram[0], OP_EQ, 1); + circpad_machine_remove_higher_token(mi, state->histogram_edges[0]/2); + tt_int_op(mi->histogram[0], OP_EQ, 0); + } + + /* 3.b. Test remove lower normal bin */ + { + tt_int_op(mi->histogram[3], OP_EQ, 2); + circpad_machine_remove_lower_token(mi, + circpad_histogram_bin_to_usec(mi, 3)+1); + circpad_machine_remove_lower_token(mi, + circpad_histogram_bin_to_usec(mi, 3)+1); + tt_int_op(mi->histogram[3], OP_EQ, 0); + tt_int_op(mi->histogram[2], OP_EQ, 2); + circpad_machine_remove_lower_token(mi, + circpad_histogram_bin_to_usec(mi, 3)+1); + circpad_machine_remove_lower_token(mi, + circpad_histogram_bin_to_usec(mi, 3)+1); + /* 3.c. No lower */ + circpad_machine_remove_lower_token(mi, + circpad_histogram_bin_to_usec(mi, 3)+1); + tt_int_op(mi->histogram[2], OP_EQ, 0); + } + + /* 4. Test remove closest + * a. Closest lower + * b. Closest higher + * c. Closest 0 + * d. Closest Infinity + */ + circpad_machine_setup_tokens(mi); + tt_int_op(mi->histogram[2], OP_EQ, 2); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1, 0); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1, 0); + tt_int_op(mi->histogram[2], OP_EQ, 0); + tt_int_op(mi->histogram[3], OP_EQ, 2); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1, 0); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1, 0); + tt_int_op(mi->histogram[3], OP_EQ, 0); + tt_int_op(mi->histogram[0], OP_EQ, 1); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1, 0); + tt_int_op(mi->histogram[0], OP_EQ, 0); + tt_int_op(mi->histogram[4], OP_EQ, 2); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 2)+1, 0); + tt_int_op(mi->histogram[4], OP_EQ, 2); + + /* 5. Test remove closest usec + * a. Closest 0 + * b. Closest lower (below midpoint) + * c. Closest higher (above midpoint) + * d. Closest Infinity + */ + circpad_machine_setup_tokens(mi); + + tt_int_op(mi->histogram[0], OP_EQ, 1); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 0)/3, 1); + tt_int_op(mi->histogram[0], OP_EQ, 0); + tt_int_op(mi->histogram[2], OP_EQ, 2); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 0)/3, 1); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 0)/3, 1); + tt_int_op(mi->histogram[2], OP_EQ, 0); + tt_int_op(mi->histogram[3], OP_EQ, 2); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 4), 1); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 4), 1); + tt_int_op(mi->histogram[3], OP_EQ, 0); + tt_int_op(mi->histogram[4], OP_EQ, 2); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 4), 1); + circpad_machine_remove_closest_token(mi, + circpad_histogram_bin_to_usec(mi, 4), 1); + tt_int_op(mi->histogram[4], OP_EQ, 2); + + // XXX: Need more coverage of the actual usec branches + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + monotime_disable_test_mocking(); + tor_free(circ_client_machine.states); + testing_disable_reproducible_rng(); +} + +void +test_circuitpadding_wronghop(void *arg) +{ + /** + * Test plan: + * 1. Padding sent from hop 1 and 3 to client + * 2. Send negotiated from hop 1 and 3 to client + * 3. Garbled negotiated cell + * 4. Padding negotiate sent to client + * 5. Send negotiate stop command for unknown machine + * 6. Send negotiated to relay + * 7. Garbled padding negotiate cell + */ + (void)arg; + uint32_t read_bw = 0, overhead_bw = 0; + cell_t cell; + signed_error_t ret; + origin_circuit_t *orig_client; + int64_t actual_mocked_monotime_start; + + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + + /* Mock this function so that our cell counting tests don't get confused by + * padding that gets sent by scheduled timers. */ + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + client_side = TO_CIRCUIT(origin_circuit_new()); + dummy_channel.cmux = circuitmux_alloc(); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, + &dummy_channel)); + orig_client = TO_ORIGIN_CIRCUIT(client_side); + + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + nodes_init(); + + 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; + + timers_initialize(); + circpad_machines_init(); + + MOCK(node_get_by_id, + node_get_by_id_mock); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + + /* Build three hops */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* verify padding was negotiated */ + tt_ptr_op(relay_side->padding_machine[0], OP_NE, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL); + + /* verify echo was sent */ + tt_int_op(n_relay_cells, OP_EQ, 1); + tt_int_op(n_client_cells, OP_EQ, 1); + + read_bw = orig_client->n_delivered_read_circ_bw; + overhead_bw = orig_client->n_overhead_read_circ_bw; + + /* 1. Test padding from first and third hop */ + circpad_deliver_recognized_relay_cell_events(client_side, + RELAY_COMMAND_DROP, + TO_ORIGIN_CIRCUIT(client_side)->cpath); + tt_int_op(read_bw, OP_EQ, + orig_client->n_delivered_read_circ_bw); + tt_int_op(overhead_bw, OP_EQ, + orig_client->n_overhead_read_circ_bw); + + circpad_deliver_recognized_relay_cell_events(client_side, + RELAY_COMMAND_DROP, + TO_ORIGIN_CIRCUIT(client_side)->cpath->next->next); + tt_int_op(read_bw, OP_EQ, + orig_client->n_delivered_read_circ_bw); + tt_int_op(overhead_bw, OP_EQ, + orig_client->n_overhead_read_circ_bw); + + circpad_deliver_recognized_relay_cell_events(client_side, + RELAY_COMMAND_DROP, + TO_ORIGIN_CIRCUIT(client_side)->cpath->next); + tt_int_op(read_bw, OP_EQ, + orig_client->n_delivered_read_circ_bw); + tt_int_op(overhead_bw, OP_LT, + orig_client->n_overhead_read_circ_bw); + + /* 2. Test padding negotiated not handled from hops 1,3 */ + ret = circpad_handle_padding_negotiated(client_side, &cell, + TO_ORIGIN_CIRCUIT(client_side)->cpath); + tt_int_op(ret, OP_EQ, -1); + + ret = circpad_handle_padding_negotiated(client_side, &cell, + TO_ORIGIN_CIRCUIT(client_side)->cpath->next->next); + tt_int_op(ret, OP_EQ, -1); + + /* 3. Garbled negotiated cell */ + memset(&cell, 255, sizeof(cell)); + ret = circpad_handle_padding_negotiated(client_side, &cell, + TO_ORIGIN_CIRCUIT(client_side)->cpath->next); + tt_int_op(ret, OP_EQ, -1); + + /* 4. Test that negotiate is dropped at origin */ + read_bw = orig_client->n_delivered_read_circ_bw; + overhead_bw = orig_client->n_overhead_read_circ_bw; + relay_send_command_from_edge(0, relay_side, + RELAY_COMMAND_PADDING_NEGOTIATE, + (void*)cell.payload, + (size_t)3, NULL); + tt_int_op(read_bw, OP_EQ, + orig_client->n_delivered_read_circ_bw); + tt_int_op(overhead_bw, OP_EQ, + orig_client->n_overhead_read_circ_bw); + + tt_int_op(n_relay_cells, OP_EQ, 2); + tt_int_op(n_client_cells, OP_EQ, 1); + + /* 5. Test that asking to stop the wrong machine does nothing */ + circpad_negotiate_padding(TO_ORIGIN_CIRCUIT(client_side), + 255, 2, CIRCPAD_COMMAND_STOP); + tt_ptr_op(client_side->padding_machine[0], OP_NE, NULL); + tt_ptr_op(client_side->padding_info[0], OP_NE, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_NE, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL); + tt_int_op(n_relay_cells, OP_EQ, 3); + tt_int_op(n_client_cells, OP_EQ, 2); + + /* 6. Sending negotiated command to relay does nothing */ + ret = circpad_handle_padding_negotiated(relay_side, &cell, NULL); + tt_int_op(ret, OP_EQ, -1); + + /* 7. Test garbled negotated cell (bad command 255) */ + memset(&cell, 0, sizeof(cell)); + ret = circpad_handle_padding_negotiate(relay_side, &cell); + tt_int_op(ret, OP_EQ, -1); + tt_int_op(n_client_cells, OP_EQ, 2); + + /* Test 2: Test no padding */ + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + + client_side = TO_CIRCUIT(origin_circuit_new()); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, + &dummy_channel)); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 0); + + /* verify no padding was negotiated */ + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + tt_int_op(n_relay_cells, OP_EQ, 3); + tt_int_op(n_client_cells, OP_EQ, 2); + + /* verify no echo was sent */ + tt_int_op(n_relay_cells, OP_EQ, 3); + tt_int_op(n_client_cells, OP_EQ, 2); + + /* Finish circuit */ + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Spoof padding negotiated on circuit with no padding */ + circpad_padding_negotiated(relay_side, + CIRCPAD_MACHINE_CIRC_SETUP, + CIRCPAD_COMMAND_START, + CIRCPAD_RESPONSE_OK); + + /* verify no padding was negotiated */ + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + circpad_padding_negotiated(relay_side, + CIRCPAD_MACHINE_CIRC_SETUP, + CIRCPAD_COMMAND_START, + CIRCPAD_RESPONSE_ERR); + + /* verify no padding was negotiated */ + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + circuitmux_detach_all_circuits(dummy_channel.cmux, NULL); + circuitmux_free(dummy_channel.cmux); + monotime_disable_test_mocking(); + UNMOCK(node_get_by_id); + UNMOCK(circuit_package_relay_cell); + UNMOCK(circuitmux_attach_circuit); + nodes_free(); + testing_disable_reproducible_rng(); +} + +void +test_circuitpadding_negotiation(void *arg) +{ + /** + * Test plan: + * 1. Test circuit where padding is supported by middle + * a. Make sure padding negotiation is sent + * b. Test padding negotiation delivery and parsing + * 2. Test circuit where padding is unsupported by middle + * a. Make sure padding negotiation is not sent + * 3. Test failure to negotiate a machine due to desync. + */ + int64_t actual_mocked_monotime_start; + (void)arg; + + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + + client_side = TO_CIRCUIT(origin_circuit_new()); + dummy_channel.cmux = circuitmux_alloc(); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, &dummy_channel)); + + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + nodes_init(); + + 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; + + timers_initialize(); + circpad_machines_init(); + + MOCK(node_get_by_id, + node_get_by_id_mock); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + + /* Build two hops */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* verify padding was negotiated */ + tt_ptr_op(relay_side->padding_machine[0], OP_NE, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL); + + /* verify echo was sent */ + tt_int_op(n_relay_cells, OP_EQ, 1); + tt_int_op(n_client_cells, OP_EQ, 1); + + /* Finish circuit */ + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Test 2: Test no padding */ + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + + client_side = TO_CIRCUIT(origin_circuit_new()); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, &dummy_channel)); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 0); + + /* verify no padding was negotiated */ + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_int_op(n_relay_cells, OP_EQ, 1); + tt_int_op(n_client_cells, OP_EQ, 1); + + /* verify no echo was sent */ + tt_int_op(n_relay_cells, OP_EQ, 1); + tt_int_op(n_client_cells, OP_EQ, 1); + + /* Finish circuit */ + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Force negotiate padding. */ + circpad_negotiate_padding(TO_ORIGIN_CIRCUIT(client_side), + CIRCPAD_MACHINE_CIRC_SETUP, + 2, CIRCPAD_COMMAND_START); + + /* verify no padding was negotiated */ + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + /* verify no echo was sent */ + tt_int_op(n_relay_cells, OP_EQ, 1); + tt_int_op(n_client_cells, OP_EQ, 1); + + /* 3. Test failure to negotiate a machine due to desync */ + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + + client_side = TO_CIRCUIT(origin_circuit_new()); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, &dummy_channel)); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + SMARTLIST_FOREACH(relay_padding_machines, + circpad_machine_spec_t *, + m, tor_free(m->states); tor_free(m)); + smartlist_free(relay_padding_machines); + relay_padding_machines = smartlist_new(); + + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* verify echo was sent */ + tt_int_op(n_client_cells, OP_EQ, 2); + tt_int_op(n_relay_cells, OP_EQ, 2); + + /* verify no padding was negotiated */ + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + circuitmux_detach_all_circuits(dummy_channel.cmux, NULL); + circuitmux_free(dummy_channel.cmux); + monotime_disable_test_mocking(); + UNMOCK(node_get_by_id); + UNMOCK(circuit_package_relay_cell); + UNMOCK(circuitmux_attach_circuit); + nodes_free(); +} + +static void +simulate_single_hop_extend(circuit_t *client, circuit_t *mid_relay, + int padding) +{ + char whatevs_key[CPATH_KEY_MATERIAL_LEN]; + char digest[DIGEST_LEN]; + tor_addr_t addr; + + // Pretend a non-padding cell was sent + circpad_cell_event_nonpadding_sent(client); + + // Receive extend cell at middle + circpad_cell_event_nonpadding_received(mid_relay); + + // Advance time a tiny bit so we can calculate an RTT + curr_mocked_time += 10 * TOR_NSEC_PER_MSEC; + monotime_coarse_set_mock_time_nsec(curr_mocked_time); + monotime_set_mock_time_nsec(curr_mocked_time); + + // Receive extended cell at middle + circpad_cell_event_nonpadding_sent(mid_relay); + + // Receive extended cell at first hop + circpad_cell_event_nonpadding_received(client); + + // Add a hop to cpath + crypt_path_t *hop = tor_malloc_zero(sizeof(crypt_path_t)); + cpath_extend_linked_list(&TO_ORIGIN_CIRCUIT(client)->cpath, hop); + + hop->magic = CRYPT_PATH_MAGIC; + hop->state = CPATH_STATE_OPEN; + + // add an extend info to indicate if this node supports padding or not. + // (set the first byte of the digest for our mocked node_get_by_id) + digest[0] = padding; + + hop->extend_info = extend_info_new( + padding ? "padding" : "non-padding", + digest, NULL, NULL, NULL, + &addr, padding); + + cpath_init_circuit_crypto(hop, whatevs_key, sizeof(whatevs_key), 0, 0); + + hop->package_window = circuit_initial_package_window(); + hop->deliver_window = CIRCWINDOW_START; + + // Signal that the hop was added + circpad_machine_event_circ_added_hop(TO_ORIGIN_CIRCUIT(client)); +} + +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 = + 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; + + /* Use EXACT removal strategy, otherwise setup_tokens() does not work */ + ret->states[CIRCPAD_STATE_BURST].token_removal = + CIRCPAD_TOKEN_REMOVAL_EXACT; + + ret->states[CIRCPAD_STATE_BURST].histogram_len = 3; + + 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[0] = 6; + ret->states[CIRCPAD_STATE_BURST].histogram[1] = 0; + ret->states[CIRCPAD_STATE_BURST].histogram[2] = 0; + + 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 = 1; + + return ret; +} + +static void +helper_create_conditional_machines(void) +{ + circpad_machine_spec_t *add = helper_create_conditional_machine(); + + if (!origin_padding_machines) + origin_padding_machines = smartlist_new(); + if (!relay_padding_machines) + relay_padding_machines = smartlist_new(); + + add->machine_num = 2; + add->is_origin_side = 1; + add->should_negotiate_end = 1; + add->target_hopnum = 2; + + /* Let's have this one end after 4 packets */ + add->states[CIRCPAD_STATE_BURST].length_dist.type = CIRCPAD_DIST_UNIFORM; + add->states[CIRCPAD_STATE_BURST].length_dist.param1 = 4; + add->states[CIRCPAD_STATE_BURST].length_dist.param2 = 4; + add->states[CIRCPAD_STATE_BURST].max_length = 4; + + add->conditions.requires_vanguards = 0; + add->conditions.min_hops = 2; + add->conditions.state_mask = CIRCPAD_CIRC_BUILDING| + CIRCPAD_CIRC_NO_STREAMS|CIRCPAD_CIRC_HAS_RELAY_EARLY; + add->conditions.purpose_mask = CIRCPAD_PURPOSE_ALL; + circpad_register_padding_machine(add, origin_padding_machines); + + add = helper_create_conditional_machine(); + add->machine_num = 3; + add->is_origin_side = 1; + add->should_negotiate_end = 1; + add->target_hopnum = 2; + + /* Let's have this one end after 4 packets */ + add->states[CIRCPAD_STATE_BURST].length_dist.type = CIRCPAD_DIST_UNIFORM; + add->states[CIRCPAD_STATE_BURST].length_dist.param1 = 4; + add->states[CIRCPAD_STATE_BURST].length_dist.param2 = 4; + add->states[CIRCPAD_STATE_BURST].max_length = 4; + + add->conditions.requires_vanguards = 1; + add->conditions.min_hops = 3; + add->conditions.state_mask = CIRCPAD_CIRC_OPENED| + CIRCPAD_CIRC_STREAMS|CIRCPAD_CIRC_HAS_NO_RELAY_EARLY; + add->conditions.purpose_mask = CIRCPAD_PURPOSE_ALL; + circpad_register_padding_machine(add, origin_padding_machines); + + add = helper_create_conditional_machine(); + add->machine_num = 2; + circpad_register_padding_machine(add, relay_padding_machines); + + add = helper_create_conditional_machine(); + add->machine_num = 3; + circpad_register_padding_machine(add, relay_padding_machines); +} + +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_i64_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_i64_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_i64_op(mi->state_length, OP_EQ, i); + } + circpad_send_padding_cell_for_callback(mi); + + tt_i64_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_i64_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_i64_op(mi->state_length, OP_EQ, i); + } + + circpad_cell_event_nonpadding_sent(client_side); + tt_i64_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_i64_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_i64_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(TO_OR_CIRCUIT(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) +{ + /** + * Test plan: + * 0. Make a few origin and client machines with diff conditions + * * vanguards, purposes, has_opened circs, no relay early + * * Client side should_negotiate_end + * * Length limits + * 1. Test STATE_END transitions + * 2. Test new machine after end with same conditions + * 3. Test new machine due to changed conditions + * * Esp: built event, no relay early, no streams + * XXX: Diff test: + * 1. Test STATE_END with pending timers + * 2. Test marking a circuit before padding callback fires + * 3. Test freeing a circuit before padding callback fires + */ + int64_t actual_mocked_monotime_start; + (void)arg; + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + testing_enable_reproducible_rng(); + + 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(); + helper_create_conditional_machines(); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + MOCK(node_get_by_id, + node_get_by_id_mock); + + /* Simulate extend. This should result in the original machine getting + * added, since the circuit is not built */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Verify that machine #2 is added */ + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + /* Deliver a padding cell to the client, to trigger burst state */ + circpad_cell_event_padding_sent(client_side); + + /* This should have trigger length shutdown condition on client.. */ + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + /* Verify machine is gone from both sides */ + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + + /* Send another event.. verify machine gets re-added properly + * (test race with shutdown) */ + simulate_single_hop_extend(client_side, relay_side, 1); + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + TO_ORIGIN_CIRCUIT(client_side)->p_streams = 0; + circpad_machine_event_circ_has_no_streams(TO_ORIGIN_CIRCUIT(client_side)); + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + /* Now make the circuit opened and send built event */ + TO_ORIGIN_CIRCUIT(client_side)->has_opened = 1; + circpad_machine_event_circ_built(TO_ORIGIN_CIRCUIT(client_side)); + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + TO_ORIGIN_CIRCUIT(client_side)->remaining_relay_early_cells = 0; + circpad_machine_event_circ_has_no_relay_early( + TO_ORIGIN_CIRCUIT(client_side)); + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + get_options_mutable()->HSLayer2Nodes = (void*)1; + TO_ORIGIN_CIRCUIT(client_side)->p_streams = (void*)1; + circpad_machine_event_circ_has_streams(TO_ORIGIN_CIRCUIT(client_side)); + + /* Verify different machine is added */ + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 3); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 3); + + /* Hold off on negotiated */ + deliver_negotiated = 0; + + /* Deliver a padding cell to the client, to trigger burst state */ + circpad_cell_event_padding_sent(client_side); + + /* This should have trigger length shutdown condition on client + * but not the response for the padding machine */ + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_NE, NULL); + + /* Verify machine is gone from the relay (but negotiated not back yet */ + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + + /* Add another hop and verify it's back */ + simulate_single_hop_extend(client_side, relay_side, 1); + + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 3); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 3); + + tt_ptr_op(client_side->padding_info[0], OP_NE, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL); + + done: + /* XXX: Free everything */ + testing_disable_reproducible_rng(); + return; +} + +/** Disabled unstable test until #29298 is implemented (see #29122) */ +#if 0 +void +test_circuitpadding_circuitsetup_machine(void *arg) +{ + int64_t actual_mocked_monotime_start; + /** + * Test case plan: + * + * 1. Simulate a normal circuit setup pattern + * a. Application traffic + * + * FIXME: This should focus more on exercising the machine + * features rather than actual traffic patterns. For example, + * test cancellation and bins empty/refill + */ + (void)arg; + + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + + dummy_channel.cmux = circuitmux_alloc(); + client_side = TO_CIRCUIT(origin_circuit_new()); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, &dummy_channel)); + + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + nodes_init(); + + 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; + + timers_initialize(); + circpad_machines_init(); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + MOCK(node_get_by_id, + node_get_by_id_mock); + + /* Test case #1: Build a 3 hop circuit, then wait and let pad */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + tt_int_op(n_client_cells, OP_EQ, 1); + tt_int_op(n_relay_cells, OP_EQ, 1); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + tt_int_op(relay_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_int_op(relay_side->padding_info[0]->is_padding_timer_scheduled, + OP_EQ, 0); + timers_advance_and_run(2000); + tt_int_op(n_client_cells, OP_EQ, 2); + tt_int_op(n_relay_cells, OP_EQ, 1); + + tt_int_op(relay_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_GAP); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + timers_advance_and_run(5000); + tt_int_op(n_client_cells, OP_EQ, 2); + tt_int_op(n_relay_cells, OP_EQ, 2); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + timers_advance_and_run(2000); + tt_int_op(n_client_cells, OP_EQ, 3); + tt_int_op(n_relay_cells, OP_EQ, 2); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + timers_advance_and_run(5000); + tt_int_op(n_client_cells, OP_EQ, 3); + tt_int_op(n_relay_cells, OP_EQ, 3); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + timers_advance_and_run(2000); + tt_int_op(n_client_cells, OP_EQ, 4); + tt_int_op(n_relay_cells, OP_EQ, 3); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + timers_advance_and_run(5000); + tt_int_op(n_client_cells, OP_EQ, 4); + tt_int_op(n_relay_cells, OP_EQ, 4); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + timers_advance_and_run(2000); + tt_int_op(n_client_cells, OP_EQ, 5); + tt_int_op(n_relay_cells, OP_EQ, 4); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + timers_advance_and_run(5000); + tt_int_op(n_client_cells, OP_EQ, 5); + tt_int_op(n_relay_cells, OP_EQ, 5); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + timers_advance_and_run(2000); + tt_int_op(n_client_cells, OP_EQ, 6); + tt_int_op(n_relay_cells, OP_EQ, 5); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + timers_advance_and_run(5000); + tt_int_op(n_client_cells, OP_EQ, 6); + tt_int_op(n_relay_cells, OP_EQ, 6); + + tt_int_op(client_side->padding_info[0]->current_state, + OP_EQ, CIRCPAD_STATE_END); + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + tt_int_op(relay_side->padding_info[0]->current_state, + OP_EQ, CIRCPAD_STATE_GAP); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + + /* Verify we can't schedule padding in END state */ + circpad_decision_t ret = + circpad_machine_schedule_padding(client_side->padding_info[0]); + tt_int_op(ret, OP_EQ, CIRCPAD_STATE_UNCHANGED); + + /* Simulate application traffic */ + circpad_cell_event_nonpadding_sent(client_side); + circpad_deliver_unrecognized_cell_events(relay_side, CELL_DIRECTION_OUT); + circpad_deliver_unrecognized_cell_events(relay_side, CELL_DIRECTION_IN); + circpad_deliver_recognized_relay_cell_events(client_side, RELAY_COMMAND_DATA, + TO_ORIGIN_CIRCUIT(client_side)->cpath->next); + + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + tt_int_op(n_client_cells, OP_EQ, 6); + tt_int_op(n_relay_cells, OP_EQ, 7); + + // Test timer cancellation + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + timers_advance_and_run(5000); + circpad_cell_event_padding_received(client_side); + + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + tt_int_op(relay_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_GAP); + + tt_int_op(n_client_cells, OP_EQ, 8); + tt_int_op(n_relay_cells, OP_EQ, 8); + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + + /* Test timer cancel due to state rules */ + circpad_cell_event_nonpadding_sent(client_side); + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_EQ, 0); + circpad_cell_event_padding_received(client_side); + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + + /* Simulate application traffic to cancel timer */ + circpad_cell_event_nonpadding_sent(client_side); + circpad_deliver_unrecognized_cell_events(relay_side, CELL_DIRECTION_OUT); + circpad_deliver_unrecognized_cell_events(relay_side, CELL_DIRECTION_IN); + circpad_deliver_recognized_relay_cell_events(client_side, RELAY_COMMAND_DATA, + TO_ORIGIN_CIRCUIT(client_side)->cpath->next); + + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + + /* No cells sent, except negotiate end from relay */ + tt_int_op(n_client_cells, OP_EQ, 8); + tt_int_op(n_relay_cells, OP_EQ, 9); + + /* Test mark for close and free */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + timers_advance_and_run(5000); + circpad_cell_event_padding_received(client_side); + + tt_int_op(n_client_cells, OP_EQ, 10); + tt_int_op(n_relay_cells, OP_EQ, 10); + + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_BURST); + tt_int_op(relay_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_GAP); + + tt_u64_op(client_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + tt_u64_op(relay_side->padding_info[0]->padding_scheduled_at_usec, + OP_NE, 0); + circuit_mark_for_close(client_side, END_CIRC_REASON_FLAG_REMOTE); + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + timers_advance_and_run(5000); + + /* No cells sent */ + tt_int_op(n_client_cells, OP_EQ, 10); + tt_int_op(n_relay_cells, OP_EQ, 10); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_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); + + return; +} +#endif /* 0 */ + +/** Helper function: Initializes a padding machine where every state uses the + * uniform probability distribution. */ +static void +helper_circpad_circ_distribution_machine_setup(int min, int max) +{ + circpad_machine_states_init(&circ_client_machine, 7); + + circpad_state_t *zero_st = &circ_client_machine.states[0]; + zero_st->next_state[CIRCPAD_EVENT_NONPADDING_RECV] = 1; + zero_st->iat_dist.type = CIRCPAD_DIST_UNIFORM; + /* param2 is upper bound, param1 is lower */ + zero_st->iat_dist.param1 = min; + zero_st->iat_dist.param2 = max; + zero_st->dist_added_shift_usec = min; + zero_st->dist_max_sample_usec = max; + + circpad_state_t *first_st = &circ_client_machine.states[1]; + first_st->next_state[CIRCPAD_EVENT_NONPADDING_RECV] = 2; + first_st->iat_dist.type = CIRCPAD_DIST_LOGISTIC; + /* param1 is Mu, param2 is sigma. */ + first_st->iat_dist.param1 = 9; + first_st->iat_dist.param2 = 3; + first_st->dist_added_shift_usec = min; + first_st->dist_max_sample_usec = max; + + circpad_state_t *second_st = &circ_client_machine.states[2]; + second_st->next_state[CIRCPAD_EVENT_NONPADDING_RECV] = 3; + second_st->iat_dist.type = CIRCPAD_DIST_LOG_LOGISTIC; + /* param1 is Alpha, param2 is 1.0/Beta */ + second_st->iat_dist.param1 = 1; + second_st->iat_dist.param2 = 0.5; + second_st->dist_added_shift_usec = min; + second_st->dist_max_sample_usec = max; + + circpad_state_t *third_st = &circ_client_machine.states[3]; + third_st->next_state[CIRCPAD_EVENT_NONPADDING_RECV] = 4; + third_st->iat_dist.type = CIRCPAD_DIST_GEOMETRIC; + /* param1 is 'p' (success probability) */ + third_st->iat_dist.param1 = 0.2; + third_st->dist_added_shift_usec = min; + third_st->dist_max_sample_usec = max; + + circpad_state_t *fourth_st = &circ_client_machine.states[4]; + fourth_st->next_state[CIRCPAD_EVENT_NONPADDING_RECV] = 5; + fourth_st->iat_dist.type = CIRCPAD_DIST_WEIBULL; + /* param1 is k, param2 is Lambda */ + fourth_st->iat_dist.param1 = 1.5; + fourth_st->iat_dist.param2 = 1; + fourth_st->dist_added_shift_usec = min; + fourth_st->dist_max_sample_usec = max; + + circpad_state_t *fifth_st = &circ_client_machine.states[5]; + fifth_st->next_state[CIRCPAD_EVENT_NONPADDING_RECV] = 6; + fifth_st->iat_dist.type = CIRCPAD_DIST_PARETO; + /* param1 is sigma, param2 is xi */ + fifth_st->iat_dist.param1 = 1; + fifth_st->iat_dist.param2 = 5; + fifth_st->dist_added_shift_usec = min; + fifth_st->dist_max_sample_usec = max; +} + +/** Simple test that the padding delays sampled from a uniform distribution + * actually faill within the uniform distribution range. */ +static void +test_circuitpadding_sample_distribution(void *arg) +{ + circpad_machine_runtime_t *mi; + int n_samples; + int n_states; + + (void) arg; + + /* mock this function so that we dont actually schedule any padding */ + MOCK(circpad_machine_schedule_padding, + circpad_machine_schedule_padding_mock); + testing_enable_reproducible_rng(); + + /* Initialize a machine with multiple probability distributions */ + circpad_machines_init(); + helper_circpad_circ_distribution_machine_setup(0, 10); + + /* Initialize machine and circuits */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + mi = client_side->padding_info[0]; + + /* For every state, sample a bunch of values from the distribution and ensure + * they fall within range. */ + for (n_states = 0 ; n_states < 6; n_states++) { + /* Make sure we in the right state */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, n_states); + + for (n_samples = 0; n_samples < 100; n_samples++) { + circpad_delay_t delay = circpad_machine_sample_delay(mi); + tt_int_op(delay, OP_GE, 0); + tt_int_op(delay, OP_LE, 10); + } + + /* send a non-padding cell to move to the next machine state */ + circpad_cell_event_nonpadding_received(client_side); + } + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + UNMOCK(circpad_machine_schedule_padding); + testing_disable_reproducible_rng(); +} + +static circpad_decision_t +circpad_machine_spec_transition_mock(circpad_machine_runtime_t *mi, + circpad_event_t event) +{ + (void) mi; + (void) event; + + return CIRCPAD_STATE_UNCHANGED; +} + +/* Test per-machine padding rate limits */ +static void +test_circuitpadding_machine_rate_limiting(void *arg) +{ + (void) arg; + bool retval; + circpad_machine_runtime_t *mi; + int i; + + /* Ignore machine transitions for the purposes of this function, we only + * really care about padding counts */ + MOCK(circpad_machine_spec_transition, circpad_machine_spec_transition_mock); + MOCK(circpad_send_command_to_hop, circpad_send_command_to_hop_mock); + testing_enable_reproducible_rng(); + + /* Setup machine and circuits */ + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + helper_create_basic_machine(); + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + mi = client_side->padding_info[0]; + /* Set up the machine info so that we can get through the basic functions */ + mi->state_length = CIRCPAD_STATE_LENGTH_INFINITE; + + /* First we are going to test the per-machine rate limits */ + circ_client_machine.max_padding_percent = 50; + circ_client_machine.allowed_padding_count = 100; + + /* Check padding limit, should be fine since we haven't sent anything yet. */ + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 0); + + /* Send 99 padding cells which is below circpad_global_allowed_cells=100, so + * the rate limit will not trigger */ + for (i=0;i<99;i++) { + circpad_send_padding_cell_for_callback(mi); + } + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 0); + + /* Now send another padding cell to pass circpad_global_allowed_cells=100, + and see that the limit will trigger */ + circpad_send_padding_cell_for_callback(mi); + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 1); + + retval = circpad_machine_schedule_padding(mi); + tt_int_op(retval, OP_EQ, CIRCPAD_STATE_UNCHANGED); + + /* Cover wrap */ + for (;i<UINT16_MAX;i++) { + circpad_send_padding_cell_for_callback(mi); + } + tt_int_op(mi->padding_sent, OP_EQ, UINT16_MAX/2+1); + + tt_ptr_op(client_side->padding_info[0], OP_EQ, mi); + for (i=0;i<UINT16_MAX;i++) { + circpad_cell_event_nonpadding_sent(client_side); + } + + tt_int_op(mi->nonpadding_sent, OP_EQ, UINT16_MAX/2); + tt_int_op(mi->padding_sent, OP_EQ, UINT16_MAX/4+1); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + testing_disable_reproducible_rng(); +} + +/* Test global padding rate limits */ +static void +test_circuitpadding_global_rate_limiting(void *arg) +{ + (void) arg; + bool retval; + circpad_machine_runtime_t *mi; + int i; + int64_t actual_mocked_monotime_start; + + /* Ignore machine transitions for the purposes of this function, we only + * really care about padding counts */ + MOCK(circpad_machine_spec_transition, circpad_machine_spec_transition_mock); + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + MOCK(monotime_absolute_usec, mock_monotime_absolute_usec); + testing_enable_reproducible_rng(); + + 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; + timers_initialize(); + + client_side = TO_CIRCUIT(origin_circuit_new()); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + dummy_channel.cmux = circuitmux_alloc(); + + /* Setup machine and circuits */ + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, &dummy_channel)); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + helper_create_basic_machine(); + relay_side->padding_machine[0] = &circ_client_machine; + relay_side->padding_info[0] = + circpad_circuit_machineinfo_new(relay_side, 0); + mi = relay_side->padding_info[0]; + /* Set up the machine info so that we can get through the basic functions */ + mi->state_length = CIRCPAD_STATE_LENGTH_INFINITE; + + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Now test the global limits by setting up the consensus */ + networkstatus_t vote1; + vote1.net_params = smartlist_new(); + smartlist_split_string(vote1.net_params, + "circpad_global_allowed_cells=100 circpad_global_max_padding_pct=50", + NULL, 0, 0); + /* Register global limits with the padding subsystem */ + circpad_new_consensus_params(&vote1); + + /* Check padding limit, should be fine since we haven't sent anything yet. */ + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 0); + + /* Send 99 padding cells which is below circpad_global_allowed_cells=100, so + * the rate limit will not trigger */ + for (i=0;i<99;i++) { + circpad_send_padding_cell_for_callback(mi); + } + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 0); + + /* Now send another padding cell to pass circpad_global_allowed_cells=100, + and see that the limit will trigger */ + circpad_send_padding_cell_for_callback(mi); + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 1); + + retval = circpad_machine_schedule_padding(mi); + tt_int_op(retval, OP_EQ, CIRCPAD_STATE_UNCHANGED); + + /* Now send 92 non-padding cells to get near the + * circpad_global_max_padding_pct=50 limit; in particular with 96 non-padding + * cells, the padding traffic is still 51% of total traffic so limit should + * trigger */ + for (i=0;i<92;i++) { + circpad_cell_event_nonpadding_sent(relay_side); + } + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 1); + + /* Send another non-padding cell to bring the padding traffic to 50% of total + * traffic and get past the limit */ + circpad_cell_event_nonpadding_sent(relay_side); + retval = circpad_machine_reached_padding_limit(mi); + tt_int_op(retval, OP_EQ, 0); + + done: + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + circuitmux_detach_all_circuits(dummy_channel.cmux, NULL); + circuitmux_free(dummy_channel.cmux); + SMARTLIST_FOREACH(vote1.net_params, char *, cp, tor_free(cp)); + smartlist_free(vote1.net_params); + testing_disable_reproducible_rng(); +} + +/* Test reduced and disabled padding */ +static void +test_circuitpadding_reduce_disable(void *arg) +{ + (void) arg; + int64_t actual_mocked_monotime_start; + + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + testing_enable_reproducible_rng(); + + nodes_init(); + dummy_channel.cmux = circuitmux_alloc(); + relay_side = (circuit_t *)new_fake_orcirc(&dummy_channel, + &dummy_channel); + client_side = (circuit_t *)origin_circuit_new(); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + circpad_machines_init(); + helper_create_conditional_machines(); + + 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; + timers_initialize(); + + /* This is needed so that we are not considered to be dormant */ + note_user_activity(20); + + MOCK(circuit_package_relay_cell, + circuit_package_relay_cell_mock); + MOCK(node_get_by_id, + node_get_by_id_mock); + + /* Simulate extend. This should result in the original machine getting + * added, since the circuit is not built */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Verify that machine #2 is added */ + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + /* Deliver a padding cell to the client, to trigger burst state */ + circpad_cell_event_padding_sent(client_side); + + /* This should have trigger length shutdown condition on client.. */ + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + + /* Verify machine is gone from both sides */ + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + + /* Now test the reduced padding machine by setting up the consensus */ + networkstatus_t vote1; + vote1.net_params = smartlist_new(); + smartlist_split_string(vote1.net_params, + "circpad_padding_reduced=1", NULL, 0, 0); + + /* Register reduced padding machine with the padding subsystem */ + circpad_new_consensus_params(&vote1); + + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Verify that machine #0 is added */ + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + tt_int_op( + circpad_machine_reached_padding_limit(client_side->padding_info[0]), + OP_EQ, 0); + tt_int_op( + circpad_machine_reached_padding_limit(relay_side->padding_info[0]), + OP_EQ, 0); + + /* Test that machines get torn down when padding is disabled */ + SMARTLIST_FOREACH(vote1.net_params, char *, cp, tor_free(cp)); + smartlist_free(vote1.net_params); + vote1.net_params = smartlist_new(); + smartlist_split_string(vote1.net_params, + "circpad_padding_disabled=1", NULL, 0, 0); + + /* Register reduced padding machine with the padding subsystem */ + circpad_new_consensus_params(&vote1); + + tt_int_op( + circpad_machine_schedule_padding(client_side->padding_info[0]), + OP_EQ, CIRCPAD_STATE_UNCHANGED); + tt_int_op( + circpad_machine_schedule_padding(relay_side->padding_info[0]), + OP_EQ, CIRCPAD_STATE_UNCHANGED); + + /* Signal that circuit is built: this event causes us to re-evaluate + * machine conditions (which don't apply because padding is disabled). */ + circpad_machine_event_circ_built(TO_ORIGIN_CIRCUIT(client_side)); + + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + + SMARTLIST_FOREACH(vote1.net_params, char *, cp, tor_free(cp)); + smartlist_free(vote1.net_params); + vote1.net_params = NULL; + circpad_new_consensus_params(&vote1); + + get_options_mutable()->ReducedCircuitPadding = 1; + + simulate_single_hop_extend(client_side, relay_side, 1); + + /* Verify that machine #0 is added */ + tt_int_op(client_side->padding_machine[0]->machine_num, OP_EQ, 2); + tt_int_op(relay_side->padding_machine[0]->machine_num, OP_EQ, 2); + + tt_int_op( + circpad_machine_reached_padding_limit(client_side->padding_info[0]), + OP_EQ, 0); + tt_int_op( + circpad_machine_reached_padding_limit(relay_side->padding_info[0]), + OP_EQ, 0); + + get_options_mutable()->CircuitPadding = 0; + + tt_int_op( + circpad_machine_schedule_padding(client_side->padding_info[0]), + OP_EQ, CIRCPAD_STATE_UNCHANGED); + tt_int_op( + circpad_machine_schedule_padding(relay_side->padding_info[0]), + OP_EQ, CIRCPAD_STATE_UNCHANGED); + + /* Signal that circuit is built: this event causes us to re-evaluate + * machine conditions (which don't apply because padding is disabled). */ + + circpad_machine_event_circ_built(TO_ORIGIN_CIRCUIT(client_side)); + + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_EQ, NULL); + + done: + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + circuitmux_detach_all_circuits(dummy_channel.cmux, NULL); + circuitmux_free(dummy_channel.cmux); + testing_disable_reproducible_rng(); +} + +/** Just a basic machine whose whole purpose is to reach the END state */ +static void +helper_create_ender_machine(void) +{ + /* Start, burst */ + circpad_machine_states_init(&circ_client_machine, 2); + + circ_client_machine.states[CIRCPAD_STATE_START]. + next_state[CIRCPAD_EVENT_NONPADDING_RECV] = CIRCPAD_STATE_END; + + circ_client_machine.conditions.state_mask = CIRCPAD_STATE_ALL; + circ_client_machine.conditions.purpose_mask = CIRCPAD_PURPOSE_ALL; +} + +static time_t mocked_timeofday; +/** Set timeval to a mock date and time. This is necessary + * to make tor_gettimeofday() mockable. */ +static void +mock_tor_gettimeofday(struct timeval *timeval) +{ + timeval->tv_sec = mocked_timeofday; + timeval->tv_usec = 0; +} + +/** Test manual managing of circuit lifetimes by the circuitpadding + * subsystem. In particular this test goes through all the cases of the + * circpad_marked_circuit_for_padding() function, via + * circuit_mark_for_close() as well as + * circuit_expire_old_circuits_clientside(). */ +static void +test_circuitpadding_manage_circuit_lifetime(void *arg) +{ + circpad_machine_runtime_t *mi; + + (void) arg; + + client_side = (circuit_t *)origin_circuit_new(); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + monotime_enable_test_mocking(); + MOCK(tor_gettimeofday, mock_tor_gettimeofday); + mocked_timeofday = 23; + + helper_create_ender_machine(); + + /* Enable manual circuit lifetime manage for this test */ + circ_client_machine.manage_circ_lifetime = 1; + + /* Test setup */ + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + mi = client_side->padding_info[0]; + + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_START); + + /* Check that the circuit is not marked for close */ + tt_int_op(client_side->marked_for_close, OP_EQ, 0); + tt_int_op(client_side->purpose, OP_EQ, CIRCUIT_PURPOSE_C_GENERAL); + + /* Mark this circuit for close due to a remote reason */ + circuit_mark_for_close(client_side, + END_CIRC_REASON_FLAG_REMOTE|END_CIRC_REASON_NONE); + tt_ptr_op(client_side->padding_info[0], OP_NE, NULL); + tt_int_op(client_side->marked_for_close, OP_NE, 0); + tt_int_op(client_side->purpose, OP_EQ, CIRCUIT_PURPOSE_C_GENERAL); + client_side->marked_for_close = 0; + + /* Mark this circuit for close due to a protocol issue */ + circuit_mark_for_close(client_side, END_CIRC_REASON_TORPROTOCOL); + tt_int_op(client_side->marked_for_close, OP_NE, 0); + tt_int_op(client_side->purpose, OP_EQ, CIRCUIT_PURPOSE_C_GENERAL); + client_side->marked_for_close = 0; + + /* Mark a measurement circuit for close */ + client_side->purpose = CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT; + circuit_mark_for_close(client_side, END_CIRC_REASON_NONE); + tt_int_op(client_side->marked_for_close, OP_NE, 0); + tt_int_op(client_side->purpose, OP_EQ, CIRCUIT_PURPOSE_C_MEASURE_TIMEOUT); + client_side->marked_for_close = 0; + + /* Mark a general circuit for close */ + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + circuit_mark_for_close(client_side, END_CIRC_REASON_NONE); + + /* Check that this circuit is still not marked for close since we are + * managing the lifetime manually, but the circuit was tagged as such by the + * circpadding subsystem */ + tt_int_op(client_side->marked_for_close, OP_EQ, 0); + tt_int_op(client_side->purpose, OP_EQ, CIRCUIT_PURPOSE_C_CIRCUIT_PADDING); + + /* We just tested case (1) from the comments of + * circpad_circuit_should_be_marked_for_close() */ + + /* Transition the machine to the END state but did not delete its machine */ + tt_ptr_op(client_side->padding_info[0], OP_NE, NULL); + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_END); + + /* We just tested case (3) from the comments of + * circpad_circuit_should_be_marked_for_close(). + * Now let's go for case (2). */ + + /* Reset the close mark */ + client_side->marked_for_close = 0; + + /* Mark this circuit for close */ + circuit_mark_for_close(client_side, 0); + + /* See that the circ got closed since we are already in END state */ + tt_int_op(client_side->marked_for_close, OP_NE, 0); + + /* We just tested case (2). Now let's see that case (4) is unreachable as + that comment claims */ + + /* First, reset all close marks and tags */ + client_side->marked_for_close = 0; + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + /* Now re-create the ender machine so that we can transition to END again */ + /* Free up some stuff first */ + circpad_circuit_free_all_machineinfos(client_side); + tor_free(circ_client_machine.states); + helper_create_ender_machine(); + + client_side->padding_machine[0] = &circ_client_machine; + client_side->padding_info[0] = + circpad_circuit_machineinfo_new(client_side, 0); + mi = client_side->padding_info[0]; + + /* Check we are in START. */ + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_START); + + /* Test that we don't expire this circuit yet */ + client_side->timestamp_dirty = 0; + client_side->state = CIRCUIT_STATE_OPEN; + tor_gettimeofday(&client_side->timestamp_began); + TO_ORIGIN_CIRCUIT(client_side)->circuit_idle_timeout = 23; + mocked_timeofday += 24; + circuit_expire_old_circuits_clientside(); + circuit_expire_old_circuits_clientside(); + circuit_expire_old_circuits_clientside(); + tt_int_op(client_side->timestamp_dirty, OP_NE, 0); + tt_int_op(client_side->marked_for_close, OP_EQ, 0); + tt_int_op(client_side->purpose, OP_EQ, CIRCUIT_PURPOSE_C_CIRCUIT_PADDING); + + /* Runaway circpad test: if the machine does not transition to end, + * test that after CIRCPAD_DELAY_MAX_SECS, we get marked anyway */ + mocked_timeofday = client_side->timestamp_dirty + + get_options()->MaxCircuitDirtiness + 2; + client_side->padding_info[0]->last_cell_time_sec = + approx_time()-(CIRCPAD_DELAY_MAX_SECS+10); + circuit_expire_old_circuits_clientside(); + tt_int_op(client_side->marked_for_close, OP_NE, 0); + + /* Test back to normal: if we had activity, we won't close */ + client_side->padding_info[0]->last_cell_time_sec = approx_time(); + client_side->marked_for_close = 0; + circuit_expire_old_circuits_clientside(); + tt_int_op(client_side->marked_for_close, OP_EQ, 0); + + /* Transition to END, but before we're past the dirty timer */ + mocked_timeofday = client_side->timestamp_dirty; + circpad_cell_event_nonpadding_received(client_side); + tt_int_op(mi->current_state, OP_EQ, CIRCPAD_STATE_END); + + /* Verify that the circuit was not closed. */ + tt_int_op(client_side->marked_for_close, OP_EQ, 0); + + /* Now that we are in END state, we can be closed by expiry, but via + * the timestamp_dirty path, not the idle path. So first test not dirty + * enough. */ + mocked_timeofday = client_side->timestamp_dirty; + circuit_expire_old_circuits_clientside(); + tt_int_op(client_side->marked_for_close, OP_EQ, 0); + mocked_timeofday = client_side->timestamp_dirty + + get_options()->MaxCircuitDirtiness + 2; + circuit_expire_old_circuits_clientside(); + tt_int_op(client_side->marked_for_close, OP_NE, 0); + + done: + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); + tor_free(circ_client_machine.states); + monotime_disable_test_mocking(); + UNMOCK(tor_gettimeofday); +} + +/** Helper for the test_circuitpadding_hs_machines test: + * + * - Create a client and relay circuit. + * - Setup right circuit purpose and attach a machine to the client circuit. + * - Verify that state transitions work as intended and state length gets + * enforced. + * + * This function is able to do this test both for intro and rend circuits + * depending on the value of <b>test_intro_circs</b>. + */ +static void +helper_test_hs_machines(bool test_intro_circs) +{ + /* Setup the circuits */ + origin_circuit_t *origin_client_side = origin_circuit_new(); + client_side = TO_CIRCUIT(origin_client_side); + client_side->purpose = CIRCUIT_PURPOSE_C_GENERAL; + + dummy_channel.cmux = circuitmux_alloc(); + relay_side = TO_CIRCUIT(new_fake_orcirc(&dummy_channel, &dummy_channel)); + relay_side->purpose = CIRCUIT_PURPOSE_OR; + + /* extend the client circ to two hops */ + simulate_single_hop_extend(client_side, relay_side, 1); + simulate_single_hop_extend(client_side, relay_side, 1); + + /* machines only apply on opened circuits */ + origin_client_side->has_opened = 1; + + /************************************/ + + /* Attaching the client machine now won't work here because of a wrong + * purpose */ + tt_assert(!client_side->padding_machine[0]); + circpad_add_matching_machines(origin_client_side, origin_padding_machines); + tt_assert(!client_side->padding_machine[0]); + + /* Change the purpose, see the machine getting attached */ + client_side->purpose = test_intro_circs ? + CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT : CIRCUIT_PURPOSE_C_REND_JOINED; + circpad_add_matching_machines(origin_client_side, origin_padding_machines); + tt_ptr_op(client_side->padding_info[0], OP_NE, NULL); + tt_ptr_op(client_side->padding_machine[0], OP_NE, NULL); + + tt_ptr_op(relay_side->padding_info[0], OP_NE, NULL); + tt_ptr_op(relay_side->padding_machine[0], OP_NE, NULL); + + /* Verify that the right machine is attached */ + tt_str_op(client_side->padding_machine[0]->name, OP_EQ, + test_intro_circs ? "client_ip_circ" : "client_rp_circ"); + tt_str_op(relay_side->padding_machine[0]->name, OP_EQ, + test_intro_circs ? "relay_ip_circ": "relay_rp_circ"); + + /***********************************/ + + /* Intro machines are at START state, but rend machines have already skipped + * to OBFUSCATE_CIRC_SETUP because of the sent PADDING_NEGOTIATE. */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_OBFUSCATE_CIRC_SETUP); + tt_int_op(relay_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_OBFUSCATE_CIRC_SETUP); + + /*Send non-padding to move the machines from START to OBFUSCATE_CIRC_SETUP */ + circpad_cell_event_nonpadding_received(client_side); + circpad_cell_event_nonpadding_received(relay_side); + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_OBFUSCATE_CIRC_SETUP); + tt_int_op(relay_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_OBFUSCATE_CIRC_SETUP); + + /* Check that the state lengths have been sampled and are within range */ + circpad_machine_runtime_t *client_machine_runtime = + client_side->padding_info[0]; + circpad_machine_runtime_t *relay_machine_runtime = + relay_side->padding_info[0]; + + if (test_intro_circs) { + /* on the client side, we don't send any padding so + * state length is not set */ + tt_i64_op(client_machine_runtime->state_length, OP_EQ, -1); + /* relay side has state limits. check them */ + tt_i64_op(relay_machine_runtime->state_length, OP_GE, + INTRO_MACHINE_MINIMUM_PADDING); + tt_i64_op(relay_machine_runtime->state_length, OP_LT, + INTRO_MACHINE_MAXIMUM_PADDING); + } else { + tt_i64_op(client_machine_runtime->state_length, OP_EQ, 1); + tt_i64_op(relay_machine_runtime->state_length, OP_EQ, 1); + } + + if (test_intro_circs) { + int i; + /* Send state_length worth of padding from the relay and see that the + * client state goes to END */ + for (i = (int) relay_machine_runtime->state_length ; i > 0 ; i--) { + circpad_send_padding_cell_for_callback(relay_machine_runtime); + } + /* See that the machine has been teared down after all the length has been + * exhausted (the padding info should now be null on both sides) */ + tt_ptr_op(relay_side->padding_info[0], OP_EQ, NULL); + tt_ptr_op(client_side->padding_info[0], OP_EQ, NULL); + } else { + int i; + /* Send state_length worth of padding and see that the state goes to END */ + for (i = (int) client_machine_runtime->state_length ; i > 0 ; i--) { + circpad_send_padding_cell_for_callback(client_machine_runtime); + } + /* See that the machine has been teared down after all the length has been + * exhausted. */ + tt_int_op(client_side->padding_info[0]->current_state, OP_EQ, + CIRCPAD_STATE_END); + } + + done: + free_fake_orcirc(TO_OR_CIRCUIT(relay_side)); + circuitmux_detach_all_circuits(dummy_channel.cmux, NULL); + circuitmux_free(dummy_channel.cmux); + free_fake_origin_circuit(TO_ORIGIN_CIRCUIT(client_side)); +} + +/** Test that the HS circuit padding machines work as intended. */ +static void +test_circuitpadding_hs_machines(void *arg) +{ + (void)arg; + + /* Test logic: + * + * 1) Register the HS machines, which aim to hide the presense of + * onion service traffic on the client-side + * + * 2) Call helper_test_hs_machines() to perform tests for the intro circuit + * machines and for the rend circuit machines. + */ + + MOCK(circuitmux_attach_circuit, circuitmux_attach_circuit_mock); + MOCK(circuit_package_relay_cell, circuit_package_relay_cell_mock); + MOCK(circuit_get_nth_node, circuit_get_nth_node_mock); + MOCK(circpad_machine_schedule_padding,circpad_machine_schedule_padding_mock); + + origin_padding_machines = smartlist_new(); + relay_padding_machines = smartlist_new(); + + nodes_init(); + + monotime_init(); + monotime_enable_test_mocking(); + monotime_set_mock_time_nsec(1*TOR_NSEC_PER_USEC); + monotime_coarse_set_mock_time_nsec(1*TOR_NSEC_PER_USEC); + curr_mocked_time = 1*TOR_NSEC_PER_USEC; + + timers_initialize(); + + /* This is needed so that we are not considered to be dormant */ + note_user_activity(20); + + /************************************/ + + /* Register the HS machines */ + circpad_machine_client_hide_intro_circuits(origin_padding_machines); + circpad_machine_client_hide_rend_circuits(origin_padding_machines); + circpad_machine_relay_hide_intro_circuits(relay_padding_machines); + circpad_machine_relay_hide_rend_circuits(relay_padding_machines); + + /***********************************/ + + /* Do the tests for the intro circuit machines */ + helper_test_hs_machines(true); + /* Do the tests for the rend circuit machines */ + helper_test_hs_machines(false); + + timers_shutdown(); + monotime_disable_test_mocking(); + + SMARTLIST_FOREACH_BEGIN(origin_padding_machines, + circpad_machine_spec_t *, m) { + machine_spec_free(m); + } SMARTLIST_FOREACH_END(m); + + SMARTLIST_FOREACH_BEGIN(relay_padding_machines, + circpad_machine_spec_t *, m) { + machine_spec_free(m); + } SMARTLIST_FOREACH_END(m); + + smartlist_free(origin_padding_machines); + smartlist_free(relay_padding_machines); + + UNMOCK(circuitmux_attach_circuit); + UNMOCK(circuit_package_relay_cell); + UNMOCK(circuit_get_nth_node); + UNMOCK(circpad_machine_schedule_padding); +} + +/** Test that we effectively ignore non-padding cells in padding circuits. */ +static void +test_circuitpadding_ignore_non_padding_cells(void *arg) +{ + int retval; + relay_header_t rh; + + (void) arg; + + client_side = (circuit_t *)origin_circuit_new(); + client_side->purpose = CIRCUIT_PURPOSE_C_CIRCUIT_PADDING; + + rh.command = RELAY_COMMAND_BEGIN; + + setup_full_capture_of_logs(LOG_INFO); + retval = handle_relay_cell_command(NULL, client_side, NULL, NULL, &rh, 0); + tt_int_op(retval, OP_EQ, 0); + expect_log_msg_containing("Ignored cell"); + + done: + ; +} + +#define TEST_CIRCUITPADDING(name, flags) \ + { #name, test_##name, (flags), NULL, NULL } + +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) */ + // TEST_CIRCUITPADDING(circuitpadding_circuitsetup_machine, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_conditions, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_rtt, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_sample_distribution, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_machine_rate_limiting, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_global_rate_limiting, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_reduce_disable, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_token_removal_lower, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_token_removal_higher, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_closest_token_removal, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_closest_token_removal_usec, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_token_removal_exact, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_manage_circuit_lifetime, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_hs_machines, TT_FORK), + TEST_CIRCUITPADDING(circuitpadding_ignore_non_padding_cells, TT_FORK), + END_OF_TESTCASES +}; 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