commit 7e3005af30b94fd1925b0be475d72875272b9044 Author: Nick Mathewson <nickm@torproject.org> Date: Fri Sep 7 19:38:21 2018 -0400 Replace "read consensus from disk" with "map consensus from disk". Implements 27244, and should save a bunch of RAM on clients. --- src/feature/dirauth/dirvote.c | 4 +- src/feature/dircache/directory.c | 18 ++++---- src/feature/nodelist/networkstatus.c | 89 +++++++++++++++++++----------------- src/feature/nodelist/networkstatus.h | 4 +- src/test/test_routerlist.c | 3 +- 5 files changed, 65 insertions(+), 53 deletions(-) diff --git a/src/feature/dirauth/dirvote.c b/src/feature/dirauth/dirvote.c index 42821760c..771e0363a 100644 --- a/src/feature/dirauth/dirvote.c +++ b/src/feature/dirauth/dirvote.c @@ -3648,7 +3648,9 @@ dirvote_publish_consensus(void) continue; } - if (networkstatus_set_current_consensus(pending->body, name, 0, NULL)) + if (networkstatus_set_current_consensus(pending->body, + strlen(pending->body), + name, 0, NULL)) log_warn(LD_DIR, "Error publishing %s consensus", name); else log_notice(LD_DIR, "Published %s consensus", name); diff --git a/src/feature/dircache/directory.c b/src/feature/dircache/directory.c index 8e5fc8683..147329902 100644 --- a/src/feature/dircache/directory.c +++ b/src/feature/dircache/directory.c @@ -2606,17 +2606,17 @@ handle_response_fetch_consensus(dir_connection_t *conn, if (looks_like_a_consensus_diff(body, body_len)) { /* First find our previous consensus. Maybe it's in ram, maybe not. */ cached_dir_t *cd = dirserv_get_consensus(flavname); - const char *consensus_body; + const char *consensus_body = NULL; size_t consensus_body_len; - char *owned_consensus = NULL; + tor_mmap_t *mapped_consensus = NULL; if (cd) { consensus_body = cd->dir; consensus_body_len = cd->dir_len; } else { - owned_consensus = networkstatus_read_cached_consensus(flavname); - if (owned_consensus) { - consensus_body = owned_consensus; - consensus_body_len = strlen(consensus_body); + mapped_consensus = networkstatus_map_cached_consensus(flavname); + if (mapped_consensus) { + consensus_body = mapped_consensus->data; + consensus_body_len = mapped_consensus->size; } } if (!consensus_body) { @@ -2629,7 +2629,7 @@ handle_response_fetch_consensus(dir_connection_t *conn, new_consensus = consensus_diff_apply(consensus_body, consensus_body_len, body, body_len); - tor_free(owned_consensus); + tor_munmap_file(mapped_consensus); if (new_consensus == NULL) { log_warn(LD_DIR, "Could not apply consensus diff received from server " "'%s:%d'", conn->base_.address, conn->base_.port); @@ -2651,7 +2651,9 @@ handle_response_fetch_consensus(dir_connection_t *conn, sourcename = "downloaded"; } - if ((r=networkstatus_set_current_consensus(consensus, flavname, 0, + if ((r=networkstatus_set_current_consensus(consensus, + strlen(consensus), + flavname, 0, conn->identity_digest))<0) { log_fn(r<-1?LOG_WARN:LOG_INFO, LD_DIR, "Unable to load %s consensus directory %s from " diff --git a/src/feature/nodelist/networkstatus.c b/src/feature/nodelist/networkstatus.c index 4338fde59..847ca0cdf 100644 --- a/src/feature/nodelist/networkstatus.c +++ b/src/feature/nodelist/networkstatus.c @@ -105,8 +105,6 @@ STATIC networkstatus_t *current_md_consensus = NULL; typedef struct consensus_waiting_for_certs_t { /** The consensus itself. */ networkstatus_t *consensus; - /** The encoded version of the consensus, nul-terminated. */ - char *body; /** When did we set the current value of consensus_waiting_for_certs? If * this is too recent, we shouldn't try to fetch a new consensus for a * little while, to give ourselves time to get certificates for this one. */ @@ -199,14 +197,11 @@ networkstatus_reset_download_failures(void) download_status_reset(&consensus_bootstrap_dl_status[i]); } -/** - * Read and and return the cached consensus of type <b>flavorname</b>. If - * <b>unverified</b> is false, get the one we haven't verified. Return NULL if - * the file isn't there. */ +/** Return the filename used to cache the consensus of a given flavor */ static char * -networkstatus_read_cached_consensus_impl(int flav, - const char *flavorname, - int unverified_consensus) +networkstatus_get_cache_fname(int flav, + const char *flavorname, + int unverified_consensus) { char buf[128]; const char *prefix; @@ -221,21 +216,35 @@ networkstatus_read_cached_consensus_impl(int flav, tor_snprintf(buf, sizeof(buf), "%s-%s-consensus", prefix, flavorname); } - char *filename = get_cachedir_fname(buf); - char *result = read_file_to_str(filename, RFTS_IGNORE_MISSING, NULL); + return get_cachedir_fname(buf); +} + +/** + * Read and and return the cached consensus of type <b>flavorname</b>. If + * <b>unverified</b> is false, get the one we haven't verified. Return NULL if + * the file isn't there. */ +static tor_mmap_t * +networkstatus_map_cached_consensus_impl(int flav, + const char *flavorname, + int unverified_consensus) +{ + char *filename = networkstatus_get_cache_fname(flav, + flavorname, + unverified_consensus); + tor_mmap_t *result = tor_mmap_file(filename); tor_free(filename); return result; } -/** Return a new string containing the current cached consensus of flavor - * <b>flavorname</b>. */ -char * -networkstatus_read_cached_consensus(const char *flavorname) - { +/** Map the file containing the current cached consensus of flavor + * <b>flavorname</b> */ +tor_mmap_t * +networkstatus_map_cached_consensus(const char *flavorname) +{ int flav = networkstatus_parse_flavor_name(flavorname); if (flav < 0) return NULL; - return networkstatus_read_cached_consensus_impl(flav, flavorname, 0); + return networkstatus_map_cached_consensus_impl(flav, flavorname, 0); } /** Read every cached v3 consensus networkstatus from the disk. */ @@ -248,24 +257,26 @@ router_reload_consensus_networkstatus(void) /* FFFF Suppress warnings if cached consensus is bad? */ for (flav = 0; flav < N_CONSENSUS_FLAVORS; ++flav) { const char *flavor = networkstatus_get_flavor_name(flav); - char *s = networkstatus_read_cached_consensus_impl(flav, flavor, 0); - if (s) { - if (networkstatus_set_current_consensus(s, flavor, flags, NULL) < -1) { + tor_mmap_t *m = networkstatus_map_cached_consensus_impl(flav, flavor, 0); + if (m) { + if (networkstatus_set_current_consensus(m->data, m->size, + flavor, flags, NULL) < -1) { log_warn(LD_FS, "Couldn't load consensus %s networkstatus from cache", flavor); } - tor_free(s); + tor_munmap_file(m); } - s = networkstatus_read_cached_consensus_impl(flav, flavor, 1); - if (s) { - if (networkstatus_set_current_consensus(s, flavor, + m = networkstatus_map_cached_consensus_impl(flav, flavor, 1); + if (m) { + if (networkstatus_set_current_consensus(m->data, m->size, + flavor, flags | NSSET_WAS_WAITING_FOR_CERTS, NULL)) { log_info(LD_FS, "Couldn't load unverified consensus %s networkstatus " "from cache", flavor); } - tor_free(s); + tor_munmap_file(m); } } @@ -1833,6 +1844,7 @@ warn_early_consensus(const networkstatus_t *c, const char *flavor, */ int networkstatus_set_current_consensus(const char *consensus, + size_t consensus_len, const char *flavor, unsigned flags, const char *source_dir) @@ -1862,7 +1874,7 @@ networkstatus_set_current_consensus(const char *consensus, /* Make sure it's parseable. */ c = networkstatus_parse_vote_from_string(consensus, - strlen(consensus), + consensus_len, NULL, NS_TYPE_CONSENSUS); if (!c) { log_warn(LD_DIR, "Unable to parse networkstatus consensus"); @@ -1951,14 +1963,12 @@ networkstatus_set_current_consensus(const char *consensus, c->valid_after > current_valid_after) { waiting = &consensus_waiting_for_certs[flav]; networkstatus_vote_free(waiting->consensus); - tor_free(waiting->body); waiting->consensus = c; free_consensus = 0; - waiting->body = tor_strdup(consensus); waiting->set_at = now; waiting->dl_failed = 0; if (!from_cache) { - write_str_to_file(unverified_fname, consensus, 0); + write_bytes_to_file(unverified_fname, consensus, consensus_len, 0); } if (dl_certs) authority_certs_fetch_missing(c, now, source_dir); @@ -2049,10 +2059,6 @@ networkstatus_set_current_consensus(const char *consensus, waiting->consensus->valid_after <= c->valid_after) { networkstatus_vote_free(waiting->consensus); waiting->consensus = NULL; - if (consensus != waiting->body) - tor_free(waiting->body); - else - waiting->body = NULL; waiting->set_at = 0; waiting->dl_failed = 0; if (unlink(unverified_fname) != 0) { @@ -2147,14 +2153,16 @@ networkstatus_note_certs_arrived(const char *source_dir) if (!waiting->consensus) continue; if (networkstatus_check_consensus_signature(waiting->consensus, 0)>=0) { - char *waiting_body = waiting->body; - if (!networkstatus_set_current_consensus( - waiting_body, - flavor_name, - NSSET_WAS_WAITING_FOR_CERTS, - source_dir)) { - tor_free(waiting_body); + tor_mmap_t *mapping = networkstatus_map_cached_consensus_impl( + i, flavor_name, 1); + if (mapping) { + networkstatus_set_current_consensus(mapping->data, + mapping->size, + flavor_name, + NSSET_WAS_WAITING_FOR_CERTS, + source_dir); } + tor_munmap_file(mapping); } } } @@ -2730,6 +2738,5 @@ networkstatus_free_all(void) networkstatus_vote_free(waiting->consensus); waiting->consensus = NULL; } - tor_free(waiting->body); } } diff --git a/src/feature/nodelist/networkstatus.h b/src/feature/nodelist/networkstatus.h index cc6badf0b..997d7cfa3 100644 --- a/src/feature/nodelist/networkstatus.h +++ b/src/feature/nodelist/networkstatus.h @@ -16,7 +16,7 @@ void networkstatus_reset_warnings(void); void networkstatus_reset_download_failures(void); -char *networkstatus_read_cached_consensus(const char *flavorname); +tor_mmap_t *networkstatus_map_cached_consensus(const char *flavorname); int router_reload_consensus_networkstatus(void); void routerstatus_free_(routerstatus_t *rs); #define routerstatus_free(rs) \ @@ -108,6 +108,7 @@ int networkstatus_consensus_has_ipv6(const or_options_t* options); #define NSSET_ACCEPT_OBSOLETE 8 #define NSSET_REQUIRE_FLAVOR 16 int networkstatus_set_current_consensus(const char *consensus, + size_t consensus_len, const char *flavor, unsigned flags, const char *source_dir); @@ -159,4 +160,3 @@ extern networkstatus_t *current_md_consensus; #endif /* defined(NETWORKSTATUS_PRIVATE) */ #endif /* !defined(TOR_NETWORKSTATUS_H) */ - diff --git a/src/test/test_routerlist.c b/src/test/test_routerlist.c index 7fe4c15b1..bf76570b3 100644 --- a/src/test/test_routerlist.c +++ b/src/test/test_routerlist.c @@ -659,7 +659,8 @@ test_skew_common(void *arg, time_t now, unsigned long *offset) MOCK(clock_skew_warning, mock_clock_skew_warning); /* Caller will call teardown_capture_of_logs() */ setup_capture_of_logs(LOG_WARN); - retval = networkstatus_set_current_consensus(consensus, "microdesc", 0, + retval = networkstatus_set_current_consensus(consensus, strlen(consensus), + "microdesc", 0, NULL); done: