commit d47a4aec666396acb10a2bfcd9797a9c6402c1fe Author: Donncha O'Cearbhaill donncha@donncha.is Date: Tue Sep 1 21:19:01 2015 +0200

Separate lookup function for service rend cache

Performing lookups in both the client and service side descriptor caches from the same rend_cache_lookup_entry() function increases the risk of accidental API misuse.

I'm separating the lookup functions to keep the caches distinct. --- src/or/connection_edge.c | 3 +-- src/or/control.c | 4 ++-- src/or/rendcache.c | 57 +++++++++++++++++++++++++++++++++------------- src/or/rendcache.h | 5 ++-- src/or/rendclient.c | 15 +++++------- 5 files changed, 53 insertions(+), 31 deletions(-)

diff --git a/src/or/connection_edge.c b/src/or/connection_edge.c index 5ea82d8..729ef8a 100644 --- a/src/or/connection_edge.c +++ b/src/or/connection_edge.c @@ -1527,8 +1527,7 @@ connection_ap_handshake_rewrite_and_attach(entry_connection_t *conn, unsigned int refetch_desc = 0; rend_cache_entry_t *entry = NULL; const int rend_cache_lookup_result = - rend_cache_lookup_entry(rend_data->onion_address, -1, &entry, - REND_CACHE_TYPE_CLIENT); + rend_cache_lookup_entry(rend_data->onion_address, -1, &entry); if (rend_cache_lookup_result < 0) { switch (-rend_cache_lookup_result) { case EINVAL: diff --git a/src/or/control.c b/src/or/control.c index 2408793..7d72342 100644 --- a/src/or/control.c +++ b/src/or/control.c @@ -1920,7 +1920,7 @@ getinfo_helper_dir(control_connection_t *control_conn, return -1; }

- if (!rend_cache_lookup_entry(question, -1, &e, REND_CACHE_TYPE_CLIENT)) { + if (!rend_cache_lookup_entry(question, -1, &e)) { /* Descriptor found in cache */ *answer = tor_strdup(e->desc); } else { @@ -1936,7 +1936,7 @@ getinfo_helper_dir(control_connection_t *control_conn, return -1; }

- if (!rend_cache_lookup_entry(question, -1, &e, REND_CACHE_TYPE_SERVICE)) { + if (!rend_cache_lookup_v2_desc_as_service(question, &e)) { /* Descriptor found in cache */ *answer = tor_strdup(e->desc); } else { diff --git a/src/or/rendcache.c b/src/or/rendcache.c index b8bdf88..0fe5a47 100644 --- a/src/or/rendcache.c +++ b/src/or/rendcache.c @@ -480,27 +480,23 @@ rend_cache_clean_v2_descs_as_dir(time_t now, size_t force_remove) } while (bytes_removed < force_remove); }

-/** Lookup in the client or service cache the given service ID <b>query</b> for - * <b>version</b>. The <b>service</b> argument determines if the lookup should - * be from the client cache or the service cache. +/** Lookup in the client cache the given service ID <b>query</b> for + * <b>version</b>. * * Return 0 if found and if <b>e</b> is non NULL, set it with the entry * found. Else, a negative value is returned and <b>e</b> is untouched. * -EINVAL means that <b>query</b> is not a valid service id. * -ENOENT means that no entry in the cache was found. */ int -rend_cache_lookup_entry(const char *query, int version, rend_cache_entry_t **e, - rend_cache_type_t cache) +rend_cache_lookup_entry(const char *query, int version, rend_cache_entry_t **e) { int ret = 0; char key[REND_SERVICE_ID_LEN_BASE32 + 2]; /* <version><query>\0 */ rend_cache_entry_t *entry = NULL; static const int default_version = 2;

- tor_assert(rend_cache_local_service); tor_assert(rend_cache); tor_assert(query); - tor_assert(cache);

if (!rend_valid_service_id(query)) { ret = -EINVAL; @@ -514,21 +510,50 @@ rend_cache_lookup_entry(const char *query, int version, rend_cache_entry_t **e, case 2: /* Default is version 2. */ default: - if(cache == REND_CACHE_TYPE_SERVICE){ - entry = strmap_get_lc(rend_cache_local_service, query); - } else if (cache == REND_CACHE_TYPE_CLIENT) { - tor_snprintf(key, sizeof(key), "%d%s", default_version, query); - entry = strmap_get_lc(rend_cache, key); - } + tor_snprintf(key, sizeof(key), "%d%s", default_version, query); + entry = strmap_get_lc(rend_cache, key); break; } if (!entry) { ret = -ENOENT; goto end; } - /* Check descriptor is parsed only if lookup is from client cache */ - if(cache == REND_CACHE_TYPE_CLIENT){ - tor_assert(entry->parsed && entry->parsed->intro_nodes); + tor_assert(entry->parsed && entry->parsed->intro_nodes); + + if (e) { + *e = entry; + } + + end: + return ret; +} + +/* + * Lookup the v2 service descriptor with the service ID <b>query</b> in the + * local service descriptor cache. Return 0 if found and if <b>e</b> is + * non NULL, set it with the entry found. Else, a negative value is returned + * and <b>e</b> is untouched. + * -EINVAL means that <b>query</b> is not a valid service id. + * -ENOENT means that no entry in the cache was found. */ +int +rend_cache_lookup_v2_desc_as_service(const char *query, rend_cache_entry_t **e) +{ + int ret = 0; + rend_cache_entry_t *entry = NULL; + + tor_assert(rend_cache_local_service); + tor_assert(query); + + if (!rend_valid_service_id(query)) { + ret = -EINVAL; + goto end; + } + + /* Lookup descriptor and return. */ + entry = strmap_get_lc(rend_cache_local_service, query); + if (!entry) { + ret = -ENOENT; + goto end; }

if (e) { diff --git a/src/or/rendcache.h b/src/or/rendcache.h index f04d087..a5ad2da 100644 --- a/src/or/rendcache.h +++ b/src/or/rendcache.h @@ -60,8 +60,9 @@ void rend_cache_clean_v2_descs_as_dir(time_t now, size_t min_to_remove); void rend_cache_purge(void); void rend_cache_free_all(void); int rend_cache_lookup_entry(const char *query, int version, - rend_cache_entry_t **entry_out, - rend_cache_type_t cache); + rend_cache_entry_t **entry_out); +int rend_cache_lookup_v2_desc_as_service(const char *query, + rend_cache_entry_t **entry_out); int rend_cache_lookup_v2_desc_as_dir(const char *query, const char **desc); /** Return value from rend_cache_store_v2_desc_as_{dir,client}. */ typedef enum { diff --git a/src/or/rendclient.c b/src/or/rendclient.c index af1abe5..a39e518 100644 --- a/src/or/rendclient.c +++ b/src/or/rendclient.c @@ -160,7 +160,7 @@ rend_client_send_introduction(origin_circuit_t *introcirc, #endif

r = rend_cache_lookup_entry(introcirc->rend_data->onion_address, -1, - &entry, REND_CACHE_TYPE_CLIENT); + &entry); /* An invalid onion address is not possible else we have a big issue. */ tor_assert(r != -EINVAL); if (r < 0 || !rend_client_any_intro_points_usable(entry)) { @@ -906,8 +906,7 @@ rend_client_refetch_v2_renddesc(rend_data_t *rend_query) return; } /* Before fetching, check if we already have a usable descriptor here. */ - if (rend_cache_lookup_entry(rend_query->onion_address, -1, &e, - REND_CACHE_TYPE_CLIENT) == 0 && + if (rend_cache_lookup_entry(rend_query->onion_address, -1, &e) == 0 && rend_client_any_intro_points_usable(e)) { log_info(LD_REND, "We would fetch a v2 rendezvous descriptor, but we " "already have a usable descriptor here. Not fetching."); @@ -988,8 +987,7 @@ rend_client_report_intro_point_failure(extend_info_t *failed_intro, rend_cache_entry_t *ent; connection_t *conn;

- r = rend_cache_lookup_entry(rend_query->onion_address, -1, &ent, - REND_CACHE_TYPE_CLIENT); + r = rend_cache_lookup_entry(rend_query->onion_address, -1, &ent); if (r < 0) { /* Either invalid onion address or cache entry not found. */ switch (-r) { @@ -1215,7 +1213,7 @@ rend_client_desc_trynow(const char *query) continue; assert_connection_ok(base_conn, now); if (rend_cache_lookup_entry(rend_data->onion_address, -1, - &entry, REND_CACHE_TYPE_CLIENT) == 0 && + &entry) == 0 && rend_client_any_intro_points_usable(entry)) { /* either this fetch worked, or it failed but there was a * valid entry from before which we should reuse */ @@ -1258,7 +1256,7 @@ rend_client_note_connection_attempt_ended(const rend_data_t *rend_data) if (*rend_data->onion_address != '\0') { /* Ignore return value; we find an entry, or we don't. */ (void) rend_cache_lookup_entry(rend_data->onion_address, -1, - &cache_entry, 0); + &cache_entry); have_onion = 1; }

@@ -1297,8 +1295,7 @@ rend_client_get_random_intro(const rend_data_t *rend_query) extend_info_t *result; rend_cache_entry_t *entry;

- ret = rend_cache_lookup_entry(rend_query->onion_address, -1, &entry, - REND_CACHE_TYPE_CLIENT); + ret = rend_cache_lookup_entry(rend_query->onion_address, -1, &entry); if (ret < 0 || !rend_client_any_intro_points_usable(entry)) { log_warn(LD_REND, "Query '%s' didn't have valid rend desc in cache. Failing.",