commit 2af254096f68f0cefadb5cb06b010d19edd2e6e1 Author: George Kadianakis desnacked@riseup.net Date: Mon Jul 17 14:45:14 2017 +0300

SR: Compute the start time of the current protocol run.

This function will be used to make the HS desc overlap function be independent of absolute times. --- src/or/shared_random_state.c | 20 ++++++++++++ src/or/shared_random_state.h | 2 ++ src/test/test_shared_random.c | 73 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 95 insertions(+)

diff --git a/src/or/shared_random_state.c b/src/or/shared_random_state.c index 89d2e8d7f..1fc1440d0 100644 --- a/src/or/shared_random_state.c +++ b/src/or/shared_random_state.c @@ -156,6 +156,26 @@ get_start_time_of_current_round(time_t now) return curr_start; }

+/** Return the start time of the current SR protocol run. For example, if the + * time is 23/06/2017 23:47:08 and a full SR protocol run is 24 hours, this + * function should return 23/06/2017 00:00:00. */ +time_t +sr_state_get_start_time_of_current_protocol_run(time_t now) +{ + int total_rounds = SHARED_RANDOM_N_ROUNDS * SHARED_RANDOM_N_PHASES; + int voting_interval = get_voting_interval(); + /* Find the time the current round started. */ + time_t beginning_of_current_round = get_start_time_of_current_round(now); + + /* Get current SR protocol round */ + int current_round = (now / voting_interval) % total_rounds; + + /* Get start time by subtracting the time elapsed from the beginning of the + protocol run */ + time_t time_elapsed_since_start_of_run = current_round * voting_interval; + return beginning_of_current_round - time_elapsed_since_start_of_run; +} + /* Return the time we should expire the state file created at <b>now</b>. * We expire the state file in the beginning of the next protocol run. */ STATIC time_t diff --git a/src/or/shared_random_state.h b/src/or/shared_random_state.h index 3526ad47d..ae1c5ac21 100644 --- a/src/or/shared_random_state.h +++ b/src/or/shared_random_state.h @@ -121,6 +121,8 @@ int sr_state_is_initialized(void); void sr_state_save(void); void sr_state_free(void);

+time_t sr_state_get_start_time_of_current_protocol_run(time_t now); + #ifdef SHARED_RANDOM_STATE_PRIVATE

STATIC int disk_state_load_from_disk_impl(const char *fname); diff --git a/src/test/test_shared_random.c b/src/test/test_shared_random.c index 026a0f382..3eb47dfbc 100644 --- a/src/test/test_shared_random.c +++ b/src/test/test_shared_random.c @@ -189,6 +189,77 @@ test_get_state_valid_until_time(void *arg) ; }

+/** Test the function that calculates the start time of the current SRV + * protocol run. */ +static void +test_get_start_time_of_current_run(void *arg) +{ + int retval; + char tbuf[ISO_TIME_LEN + 1]; + time_t current_time, run_start_time; + + (void) arg; + + { + /* Get start time if called at 00:00:01 */ + retval = parse_rfc1123_time("Mon, 20 Apr 2015 00:00:01 UTC", + &current_time); + tt_int_op(retval, ==, 0); + run_start_time = + sr_state_get_start_time_of_current_protocol_run(current_time); + + /* Compare it with the correct result */ + format_iso_time(tbuf, run_start_time); + tt_str_op("2015-04-20 00:00:00", OP_EQ, tbuf); + } + + { + retval = parse_rfc1123_time("Mon, 20 Apr 2015 23:59:59 UTC", + &current_time); + tt_int_op(retval, ==, 0); + run_start_time = + sr_state_get_start_time_of_current_protocol_run(current_time); + + /* Compare it with the correct result */ + format_iso_time(tbuf, run_start_time); + tt_str_op("2015-04-20 00:00:00", OP_EQ, tbuf); + } + + { + retval = parse_rfc1123_time("Mon, 20 Apr 2015 00:00:00 UTC", + &current_time); + tt_int_op(retval, ==, 0); + run_start_time = + sr_state_get_start_time_of_current_protocol_run(current_time); + + /* Compare it with the correct result */ + format_iso_time(tbuf, run_start_time); + tt_str_op("2015-04-20 00:00:00", OP_EQ, tbuf); + } + + /* Now let's alter the voting schedule and check the correctness of the + * function. Voting interval of 10 seconds, means that an SRV protocol run + * takes 10 seconds * 24 rounds = 4 mins */ + { + or_options_t *options = get_options_mutable(); + options->V3AuthVotingInterval = 10; + options->TestingV3AuthInitialVotingInterval = 10; + retval = parse_rfc1123_time("Mon, 20 Apr 2015 00:15:32 UTC", + &current_time); + + tt_int_op(retval, ==, 0); + run_start_time = + sr_state_get_start_time_of_current_protocol_run(current_time); + + /* Compare it with the correct result */ + format_iso_time(tbuf, run_start_time); + tt_str_op("2015-04-20 00:12:00", OP_EQ, tbuf); + } + + done: + ; +} + /* Mock function to immediately return our local 'mock_consensus'. */ static networkstatus_t * mock_networkstatus_get_live_consensus(time_t now) @@ -1272,6 +1343,8 @@ struct testcase_t sr_tests[] = { NULL, NULL }, { "get_next_valid_after_time", test_get_next_valid_after_time, TT_FORK, NULL, NULL }, + { "get_start_time_of_current_run", test_get_start_time_of_current_run, + TT_FORK, NULL, NULL }, { "get_state_valid_until_time", test_get_state_valid_until_time, TT_FORK, NULL, NULL }, { "vote", test_vote, TT_FORK,