From e30516f33f53d34c39d3613cecca0f4567b8e11e Mon Sep 17 00:00:00 2001 From: Nick Mathewson Date: Sun, 8 Jan 2006 21:26:33 +0000 Subject: [PATCH] Fix bug 236: caches should cache up to 16 unrecognized network-status docs. svn:r5754 --- src/or/dirserv.c | 43 +++++++++++++++++++++++++--- src/or/routerlist.c | 69 +++++++++++++++++++++++++++++++-------------- 2 files changed, 87 insertions(+), 25 deletions(-) diff --git a/src/or/dirserv.c b/src/or/dirserv.c index 3970cdd631..f3ca5fda9e 100644 --- a/src/or/dirserv.c +++ b/src/or/dirserv.c @@ -17,6 +17,9 @@ const char dirserv_c_id[] = #define ROUTER_ALLOW_SKEW (60*60*12) /* 12 hours */ /** How many seconds do we wait before regenerating the directory? */ #define DIR_REGEN_SLACK_TIME 30 +/** If we're a cache, keep this many networkstatuses around from non-trusted + * directory authorities. */ +#define MAX_UNTRUSTED_NETWORKSTATUSES 16 extern long stats_n_seconds_working; @@ -984,28 +987,60 @@ dirserv_set_cached_directory(const char *directory, time_t published, * the cache. */ void -dirserv_set_cached_networkstatus_v2(const char *directory, +dirserv_set_cached_networkstatus_v2(const char *networkstatus, const char *identity, time_t published) { cached_dir_t *d; + smartlist_t *trusted_dirs; if (!cached_v2_networkstatus) cached_v2_networkstatus = digestmap_new(); if (!(d = digestmap_get(cached_v2_networkstatus, identity))) { - if (!directory) + if (!networkstatus) return; d = tor_malloc_zero(sizeof(cached_dir_t)); digestmap_set(cached_v2_networkstatus, identity, d); } tor_assert(d); - if (directory) { - set_cached_dir(d, tor_strdup(directory), published); + if (networkstatus) { + if (published > d->published) { + set_cached_dir(d, tor_strdup(networkstatus), published); + } else { + networkstatus_free(networkstatus); + } } else { free_cached_dir(d); digestmap_remove(cached_v2_networkstatus, identity); } + + router_get_trusted_dir_servers(&trusted_dirs); + if (digestmap_size(cached_v2_networkstatus) > + smartlist_len(trusted_dirs) + MAX_UNTRUSTED_NETWORKSTATUSES) { + /* We need to remove the oldest untrusted networkstatus. */ + const char *oldest = NULL; + time_t oldest_published = TIME_MAX; + digestmap_iter_t *iter; + + for (iter = digestmap_iter_init(cached_v2_networkstatus); + !digestmap_iter_done(iter); + iter = digestmap_iter_next(cached_v2_networkstatus, iter)) { + const char *ident; + void *val; + digestmap_iter_get(iter, &ident, &val); + d = val; + if (d->published < oldest_published && + !router_get_trusteddirserver_by_digest(ident)) { + oldest = ident; + oldest_published = d->published; + } + } + tor_assert(oldest); + d = digestmap_remove(cached_v2_networkstatus, oldest); + if (d) + free_cached_dir(d); + } } /** Helper: If we're an authority for the right directory version (the diff --git a/src/or/routerlist.c b/src/or/routerlist.c index 44139d1369..d79d8931a7 100644 --- a/src/or/routerlist.c +++ b/src/or/routerlist.c @@ -1938,6 +1938,30 @@ _compare_networkstatus_published_on(const void **_a, const void **_b) return 0; } +/** Add the parsed neworkstatus in ns (with original document in + * s to the disk cache (and the in-memory directory server cache) as + * appropriate. */ +static int +add_networkstatus_to_cache(const char *s, + networkstatus_source_t source, + networkstatus_t *ns) +{ + if (source != NS_FROM_CACHE) { + char *fn = networkstatus_get_cache_filename(ns); + if (write_str_to_file(fn, s, 0)<0) { + notice(LD_FS, "Couldn't write cached network status to \"%s\"", fn); + } + tor_free(fn); + } + + if (get_options()->DirPort) + dirserv_set_cached_networkstatus_v2(s, + ns->identity_digest, + ns->published_on); + + return 0; +} + /** How far in the future do we allow a network-status to get before removing * it? (seconds) */ #define NETWORKSTATUS_ALLOW_SKEW (48*60*60) @@ -1969,7 +1993,8 @@ router_set_networkstatus(const char *s, time_t arrived_at, int i, found; time_t now; int skewed = 0; - trusted_dir_server_t *trusted_dir; + trusted_dir_server_t *trusted_dir = NULL; + const char *source_desc = NULL; char fp[HEX_DIGEST_LEN+1]; char published[ISO_TIME_LEN+1]; @@ -1978,12 +2003,18 @@ router_set_networkstatus(const char *s, time_t arrived_at, warn(LD_DIR, "Couldn't parse network status."); return -1; } + base16_encode(fp, HEX_DIGEST_LEN+1, ns->identity_digest, DIGEST_LEN); if (!(trusted_dir = router_get_trusteddirserver_by_digest(ns->identity_digest))) { info(LD_DIR, "Network status was signed, but not by an authoritative " "directory we recognize."); - networkstatus_free(ns); - return -1; + if (!get_options()->DirPort) { + networkstatus_free(ns); + return 0; + } + source_desc = fp; + } else { + source_desc = trusted_dir->description; } now = time(NULL); if (arrived_at > now) @@ -1996,7 +2027,7 @@ router_set_networkstatus(const char *s, time_t arrived_at, if (ns->published_on > now + NETWORKSTATUS_ALLOW_SKEW) { warn(LD_GENERAL, "Network status from %s was published in the future " "(%s GMT). Somebody is skewed here: check your clock. Not caching.", - trusted_dir->description, published); + source_desc, published); skewed = 1; } @@ -2009,8 +2040,6 @@ router_set_networkstatus(const char *s, time_t arrived_at, return 0; } - base16_encode(fp, HEX_DIGEST_LEN+1, ns->identity_digest, DIGEST_LEN); - if (requested_fingerprints) { if (smartlist_string_isin(requested_fingerprints, fp)) { smartlist_string_remove(requested_fingerprints, fp); @@ -2025,7 +2054,15 @@ router_set_networkstatus(const char *s, time_t arrived_at, } } - if (source != NS_FROM_CACHE) + if (!trusted_dir) { + if (!skewed && get_options()->DirPort) { + add_networkstatus_to_cache(s, source, ns); + networkstatus_free(ns); + } + return 0; + } + + if (source != NS_FROM_CACHE && trusted_dir) trusted_dir->n_networkstatus_failures = 0; found = 0; @@ -2075,8 +2112,8 @@ router_set_networkstatus(const char *s, time_t arrived_at, SMARTLIST_FOREACH(ns->entries, routerstatus_t *, rs, { - if (!router_get_by_descriptor_digest(rs->descriptor_digest)) - rs->need_to_mirror = 1; + if (!router_get_by_descriptor_digest(rs->descriptor_digest)) + rs->need_to_mirror = 1; }); info(LD_DIR, "Setting networkstatus %s %s (published %s)", @@ -2087,21 +2124,11 @@ router_set_networkstatus(const char *s, time_t arrived_at, smartlist_sort(networkstatus_list, _compare_networkstatus_published_on); - if (source != NS_FROM_CACHE && !skewed) { - char *fn = networkstatus_get_cache_filename(ns); - if (write_str_to_file(fn, s, 0)<0) { - notice(LD_FS, "Couldn't write cached network status to \"%s\"", fn); - } - tor_free(fn); - } + if (!skewed) + add_networkstatus_to_cache(s, source, ns); networkstatus_list_update_recent(now); - if (get_options()->DirPort && !skewed) - dirserv_set_cached_networkstatus_v2(s, - ns->identity_digest, - ns->published_on); - return 0; }