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Diffstat (limited to 'src/or/shared_random_client.c')
| -rw-r--r-- | src/or/shared_random_client.c | 260 |
1 files changed, 0 insertions, 260 deletions
diff --git a/src/or/shared_random_client.c b/src/or/shared_random_client.c deleted file mode 100644 index 42a5b42f60..0000000000 --- a/src/or/shared_random_client.c +++ /dev/null @@ -1,260 +0,0 @@ -/* Copyright (c) 2018-2018, The Tor Project, Inc. */ -/* See LICENSE for licensing information */ - -/** - * \file shared_random_client.c - * \brief This file contains functions that are from the shared random - * subsystem but used by many part of tor. The full feature is built - * as part of the dirauth module. - **/ - -#define SHARED_RANDOM_CLIENT_PRIVATE -#include "or/shared_random_client.h" - -#include "or/config.h" -#include "or/voting_schedule.h" -#include "or/networkstatus.h" -#include "lib/encoding/binascii.h" - -#include "or/networkstatus_st.h" - -/* Convert a given srv object to a string for the control port. This doesn't - * fail and the srv object MUST be valid. */ -static char * -srv_to_control_string(const sr_srv_t *srv) -{ - char *srv_str; - char srv_hash_encoded[SR_SRV_VALUE_BASE64_LEN + 1]; - tor_assert(srv); - - sr_srv_encode(srv_hash_encoded, sizeof(srv_hash_encoded), srv); - tor_asprintf(&srv_str, "%s", srv_hash_encoded); - return srv_str; -} - -/* Return the voting interval of the tor vote subsystem. */ -int -get_voting_interval(void) -{ - int interval; - networkstatus_t *consensus = networkstatus_get_live_consensus(time(NULL)); - - if (consensus) { - interval = (int)(consensus->fresh_until - consensus->valid_after); - } else { - /* Same for both a testing and real network. We voluntarily ignore the - * InitialVotingInterval since it complexifies things and it doesn't - * affect the SR protocol. */ - interval = get_options()->V3AuthVotingInterval; - } - tor_assert(interval > 0); - return interval; -} - -/* Given the time <b>now</b>, return the start time of the current round of - * the SR protocol. For example, if it's 23:47:08, the current round thus - * started at 23:47:00 for a voting interval of 10 seconds. */ -time_t -get_start_time_of_current_round(void) -{ - const or_options_t *options = get_options(); - int voting_interval = get_voting_interval(); - /* First, get the start time of the next round */ - time_t next_start = voting_schedule_get_next_valid_after_time(); - /* Now roll back next_start by a voting interval to find the start time of - the current round. */ - time_t curr_start = voting_schedule_get_start_of_next_interval( - next_start - voting_interval - 1, - voting_interval, - options->TestingV3AuthVotingStartOffset); - return curr_start; -} - -/* - * Public API - */ - -/* Encode the given shared random value and put it in dst. Destination - * buffer must be at least SR_SRV_VALUE_BASE64_LEN plus the NULL byte. */ -void -sr_srv_encode(char *dst, size_t dst_len, const sr_srv_t *srv) -{ - int ret; - /* Extra byte for the NULL terminated char. */ - char buf[SR_SRV_VALUE_BASE64_LEN + 1]; - - tor_assert(dst); - tor_assert(srv); - tor_assert(dst_len >= sizeof(buf)); - - ret = base64_encode(buf, sizeof(buf), (const char *) srv->value, - sizeof(srv->value), 0); - /* Always expect the full length without the NULL byte. */ - tor_assert(ret == (sizeof(buf) - 1)); - tor_assert(ret <= (int) dst_len); - strlcpy(dst, buf, dst_len); -} - -/* Return the current SRV string representation for the control port. Return a - * newly allocated string on success containing the value else "" if not found - * or if we don't have a valid consensus yet. */ -char * -sr_get_current_for_control(void) -{ - char *srv_str; - const networkstatus_t *c = networkstatus_get_latest_consensus(); - if (c && c->sr_info.current_srv) { - srv_str = srv_to_control_string(c->sr_info.current_srv); - } else { - srv_str = tor_strdup(""); - } - return srv_str; -} - -/* Return the previous SRV string representation for the control port. Return - * a newly allocated string on success containing the value else "" if not - * found or if we don't have a valid consensus yet. */ -char * -sr_get_previous_for_control(void) -{ - char *srv_str; - const networkstatus_t *c = networkstatus_get_latest_consensus(); - if (c && c->sr_info.previous_srv) { - srv_str = srv_to_control_string(c->sr_info.previous_srv); - } else { - srv_str = tor_strdup(""); - } - return srv_str; -} - -/* Return current shared random value from the latest consensus. Caller can - * NOT keep a reference to the returned pointer. Return NULL if none. */ -const sr_srv_t * -sr_get_current(const networkstatus_t *ns) -{ - const networkstatus_t *consensus; - - /* Use provided ns else get a live one */ - if (ns) { - consensus = ns; - } else { - consensus = networkstatus_get_live_consensus(approx_time()); - } - /* Ideally we would never be asked for an SRV without a live consensus. Make - * sure this assumption is correct. */ - tor_assert_nonfatal(consensus); - - if (consensus) { - return consensus->sr_info.current_srv; - } - return NULL; -} - -/* Return previous shared random value from the latest consensus. Caller can - * NOT keep a reference to the returned pointer. Return NULL if none. */ -const sr_srv_t * -sr_get_previous(const networkstatus_t *ns) -{ - const networkstatus_t *consensus; - - /* Use provided ns else get a live one */ - if (ns) { - consensus = ns; - } else { - consensus = networkstatus_get_live_consensus(approx_time()); - } - /* Ideally we would never be asked for an SRV without a live consensus. Make - * sure this assumption is correct. */ - tor_assert_nonfatal(consensus); - - if (consensus) { - return consensus->sr_info.previous_srv; - } - return NULL; -} - -/* Parse a list of arguments from a SRV value either from a vote, consensus - * or from our disk state and return a newly allocated srv object. NULL is - * returned on error. - * - * The arguments' order: - * num_reveals, value - */ -sr_srv_t * -sr_parse_srv(const smartlist_t *args) -{ - char *value; - int ok, ret; - uint64_t num_reveals; - sr_srv_t *srv = NULL; - - tor_assert(args); - - if (smartlist_len(args) < 2) { - goto end; - } - - /* First argument is the number of reveal values */ - num_reveals = tor_parse_uint64(smartlist_get(args, 0), - 10, 0, UINT64_MAX, &ok, NULL); - if (!ok) { - goto end; - } - /* Second and last argument is the shared random value it self. */ - value = smartlist_get(args, 1); - if (strlen(value) != SR_SRV_VALUE_BASE64_LEN) { - goto end; - } - - srv = tor_malloc_zero(sizeof(*srv)); - srv->num_reveals = num_reveals; - /* We subtract one byte from the srclen because the function ignores the - * '=' character in the given buffer. This is broken but it's a documented - * behavior of the implementation. */ - ret = base64_decode((char *) srv->value, sizeof(srv->value), value, - SR_SRV_VALUE_BASE64_LEN - 1); - if (ret != sizeof(srv->value)) { - tor_free(srv); - srv = NULL; - goto end; - } - end: - return srv; -} - -/** 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(); - - /* 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 (in seconds) it takes to complete a full SR protocol phase - * (e.g. the commit phase). */ -unsigned int -sr_state_get_phase_duration(void) -{ - return SHARED_RANDOM_N_ROUNDS * get_voting_interval(); -} - -/** Return the time (in seconds) it takes to complete a full SR protocol run */ -unsigned int -sr_state_get_protocol_run_duration(void) -{ - int total_protocol_rounds = SHARED_RANDOM_N_ROUNDS * SHARED_RANDOM_N_PHASES; - return total_protocol_rounds * get_voting_interval(); -} - |