diff options
Diffstat (limited to 'src/or/rendcommon.c')
| -rw-r--r-- | src/or/rendcommon.c | 161 |
1 files changed, 134 insertions, 27 deletions
diff --git a/src/or/rendcommon.c b/src/or/rendcommon.c index 3d2b706104..82202b9058 100644 --- a/src/or/rendcommon.c +++ b/src/or/rendcommon.c @@ -1,5 +1,5 @@ /* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. - * Copyright (c) 2007-2013, The Tor Project, Inc. */ + * Copyright (c) 2007-2015, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** @@ -155,7 +155,7 @@ rend_compute_v2_desc_id(char *desc_id_out, const char *service_id, } /* Calculate current time-period. */ time_period = get_time_period(now, 0, service_id_binary); - /* Calculate secret-id-part = h(time-period + replica). */ + /* Calculate secret-id-part = h(time-period | replica). */ get_secret_id_part_bytes(secret_id_part, time_period, descriptor_cookie, replica); /* Calculate descriptor ID. */ @@ -411,7 +411,7 @@ rend_desc_v2_is_parsable(rend_encoded_v2_service_descriptor_t *desc) &test_intro_content, &test_intro_size, &test_encoded_size, - &test_next, desc->desc_str); + &test_next, desc->desc_str, 1); rend_service_descriptor_free(test_parsed); tor_free(test_intro_content); return (res >= 0); @@ -528,7 +528,7 @@ rend_encode_v2_descriptors(smartlist_t *descs_out, return -1; } /* Base64-encode introduction points. */ - ipos_base64 = tor_malloc_zero(ipos_len * 2); + ipos_base64 = tor_calloc(ipos_len, 2); if (base64_encode(ipos_base64, ipos_len * 2, ipos, ipos_len)<0) { log_warn(LD_REND, "Could not encode introduction point string to " "base64. length=%d", (int)ipos_len); @@ -556,7 +556,7 @@ rend_encode_v2_descriptors(smartlist_t *descs_out, char desc_digest[DIGEST_LEN]; rend_encoded_v2_service_descriptor_t *enc = tor_malloc_zero(sizeof(rend_encoded_v2_service_descriptor_t)); - /* Calculate secret-id-part = h(time-period + cookie + replica). */ + /* Calculate secret-id-part = h(time-period | cookie | replica). */ get_secret_id_part_bytes(secret_id_part, time_period, descriptor_cookie, k); base32_encode(secret_id_part_base32, sizeof(secret_id_part_base32), @@ -704,6 +704,9 @@ static strmap_t *rend_cache = NULL; * directories. */ static digestmap_t *rend_cache_v2_dir = NULL; +/** DOCDOC */ +static size_t rend_cache_total_allocation = 0; + /** Initializes the service descriptor cache. */ void @@ -713,12 +716,64 @@ rend_cache_init(void) rend_cache_v2_dir = digestmap_new(); } +/** Return the approximate number of bytes needed to hold <b>e</b>. */ +static size_t +rend_cache_entry_allocation(const rend_cache_entry_t *e) +{ + if (!e) + return 0; + + /* This doesn't count intro_nodes or key size */ + return sizeof(*e) + e->len + sizeof(*e->parsed); +} + +/** DOCDOC */ +size_t +rend_cache_get_total_allocation(void) +{ + return rend_cache_total_allocation; +} + +/** Decrement the total bytes attributed to the rendezvous cache by n. */ +static void +rend_cache_decrement_allocation(size_t n) +{ + static int have_underflowed = 0; + + if (rend_cache_total_allocation >= n) { + rend_cache_total_allocation -= n; + } else { + rend_cache_total_allocation = 0; + if (! have_underflowed) { + have_underflowed = 1; + log_warn(LD_BUG, "Underflow in rend_cache_decrement_allocation"); + } + } +} + +/** Increase the total bytes attributed to the rendezvous cache by n. */ +static void +rend_cache_increment_allocation(size_t n) +{ + static int have_overflowed = 0; + if (rend_cache_total_allocation <= SIZE_MAX - n) { + rend_cache_total_allocation += n; + } else { + rend_cache_total_allocation = SIZE_MAX; + if (! have_overflowed) { + have_overflowed = 1; + log_warn(LD_BUG, "Overflow in rend_cache_increment_allocation"); + } + } +} + /** Helper: free storage held by a single service descriptor cache entry. */ static void rend_cache_entry_free(rend_cache_entry_t *e) { if (!e) return; + rend_cache_decrement_allocation(rend_cache_entry_allocation(e)); rend_service_descriptor_free(e->parsed); tor_free(e->desc); tor_free(e); @@ -740,6 +795,7 @@ rend_cache_free_all(void) digestmap_free(rend_cache_v2_dir, rend_cache_entry_free_); rend_cache = NULL; rend_cache_v2_dir = NULL; + rend_cache_total_allocation = 0; } /** Removes all old entries from the service descriptor cache. @@ -777,31 +833,46 @@ rend_cache_purge(void) } /** Remove all old v2 descriptors and those for which this hidden service - * directory is not responsible for any more. */ + * directory is not responsible for any more. + * + * If at all possible, remove at least <b>force_remove</b> bytes of data. + */ void -rend_cache_clean_v2_descs_as_dir(time_t now) +rend_cache_clean_v2_descs_as_dir(time_t now, size_t force_remove) { digestmap_iter_t *iter; time_t cutoff = now - REND_CACHE_MAX_AGE - REND_CACHE_MAX_SKEW; - for (iter = digestmap_iter_init(rend_cache_v2_dir); - !digestmap_iter_done(iter); ) { - const char *key; - void *val; - rend_cache_entry_t *ent; - digestmap_iter_get(iter, &key, &val); - ent = val; - if (ent->parsed->timestamp < cutoff || - !hid_serv_responsible_for_desc_id(key)) { - char key_base32[REND_DESC_ID_V2_LEN_BASE32 + 1]; - base32_encode(key_base32, sizeof(key_base32), key, DIGEST_LEN); - log_info(LD_REND, "Removing descriptor with ID '%s' from cache", - safe_str_client(key_base32)); - iter = digestmap_iter_next_rmv(rend_cache_v2_dir, iter); - rend_cache_entry_free(ent); - } else { - iter = digestmap_iter_next(rend_cache_v2_dir, iter); + const int LAST_SERVED_CUTOFF_STEP = 1800; + time_t last_served_cutoff = cutoff; + size_t bytes_removed = 0; + do { + for (iter = digestmap_iter_init(rend_cache_v2_dir); + !digestmap_iter_done(iter); ) { + const char *key; + void *val; + rend_cache_entry_t *ent; + digestmap_iter_get(iter, &key, &val); + ent = val; + if (ent->parsed->timestamp < cutoff || + ent->last_served < last_served_cutoff || + !hid_serv_responsible_for_desc_id(key)) { + char key_base32[REND_DESC_ID_V2_LEN_BASE32 + 1]; + base32_encode(key_base32, sizeof(key_base32), key, DIGEST_LEN); + log_info(LD_REND, "Removing descriptor with ID '%s' from cache", + safe_str_client(key_base32)); + bytes_removed += rend_cache_entry_allocation(ent); + iter = digestmap_iter_next_rmv(rend_cache_v2_dir, iter); + rend_cache_entry_free(ent); + } else { + iter = digestmap_iter_next(rend_cache_v2_dir, iter); + } } - } + + /* In case we didn't remove enough bytes, advance the cutoff a little. */ + last_served_cutoff += LAST_SERVED_CUTOFF_STEP; + if (last_served_cutoff > now) + break; + } while (bytes_removed < force_remove); } /** Determines whether <b>a</b> is in the interval of <b>b</b> (excluded) and @@ -903,6 +974,7 @@ rend_cache_lookup_v2_desc_as_dir(const char *desc_id, const char **desc) e = digestmap_get(rend_cache_v2_dir, desc_id_digest); if (e) { *desc = e->desc; + e->last_served = approx_time(); return 1; } return 0; @@ -924,6 +996,7 @@ rend_cache_lookup_v2_desc_as_dir(const char *desc_id, const char **desc) rend_cache_store_status_t rend_cache_store_v2_desc_as_dir(const char *desc) { + const or_options_t *options = get_options(); rend_service_descriptor_t *parsed; char desc_id[DIGEST_LEN]; char *intro_content; @@ -945,7 +1018,7 @@ rend_cache_store_v2_desc_as_dir(const char *desc) } while (rend_parse_v2_service_descriptor(&parsed, desc_id, &intro_content, &intro_size, &encoded_size, - &next_desc, current_desc) >= 0) { + &next_desc, current_desc, 1) >= 0) { number_parsed++; /* We don't care about the introduction points. */ tor_free(intro_content); @@ -992,7 +1065,13 @@ rend_cache_store_v2_desc_as_dir(const char *desc) if (!e) { e = tor_malloc_zero(sizeof(rend_cache_entry_t)); digestmap_set(rend_cache_v2_dir, desc_id, e); + /* Treat something just uploaded as having been served a little + * while ago, so that flooding with new descriptors doesn't help + * too much. + */ + e->last_served = approx_time() - 3600; } else { + rend_cache_decrement_allocation(rend_cache_entry_allocation(e)); rend_service_descriptor_free(e->parsed); tor_free(e->desc); } @@ -1000,9 +1079,16 @@ rend_cache_store_v2_desc_as_dir(const char *desc) e->parsed = parsed; e->desc = tor_strndup(current_desc, encoded_size); e->len = encoded_size; + rend_cache_increment_allocation(rend_cache_entry_allocation(e)); log_info(LD_REND, "Successfully stored service descriptor with desc ID " "'%s' and len %d.", safe_str(desc_id_base32), (int)encoded_size); + + /* Statistics: Note down this potentially new HS. */ + if (options->HiddenServiceStatistics) { + rep_hist_stored_maybe_new_hs(e->parsed->pk); + } + number_stored++; goto advance; skip: @@ -1034,10 +1120,14 @@ rend_cache_store_v2_desc_as_dir(const char *desc) * If the descriptor's service ID does not match * <b>rend_query</b>-\>onion_address, reject it. * + * If the descriptor's descriptor ID doesn't match <b>desc_id_base32</b>, + * reject it. + * * Return an appropriate rend_cache_store_status_t. */ rend_cache_store_status_t rend_cache_store_v2_desc_as_client(const char *desc, + const char *desc_id_base32, const rend_data_t *rend_query) { /*XXXX this seems to have a bit of duplicate code with @@ -1064,14 +1154,23 @@ rend_cache_store_v2_desc_as_client(const char *desc, time_t now = time(NULL); char key[REND_SERVICE_ID_LEN_BASE32+2]; char service_id[REND_SERVICE_ID_LEN_BASE32+1]; + char want_desc_id[DIGEST_LEN]; rend_cache_entry_t *e; rend_cache_store_status_t retval = RCS_BADDESC; tor_assert(rend_cache); tor_assert(desc); + tor_assert(desc_id_base32); + memset(want_desc_id, 0, sizeof(want_desc_id)); + if (base32_decode(want_desc_id, sizeof(want_desc_id), + desc_id_base32, strlen(desc_id_base32)) != 0) { + log_warn(LD_BUG, "Couldn't decode base32 %s for descriptor id.", + escaped_safe_str_client(desc_id_base32)); + goto err; + } /* Parse the descriptor. */ if (rend_parse_v2_service_descriptor(&parsed, desc_id, &intro_content, &intro_size, &encoded_size, - &next_desc, desc) < 0) { + &next_desc, desc, 0) < 0) { log_warn(LD_REND, "Could not parse descriptor."); goto err; } @@ -1086,6 +1185,12 @@ rend_cache_store_v2_desc_as_client(const char *desc, service_id, safe_str(rend_query->onion_address)); goto err; } + if (tor_memneq(desc_id, want_desc_id, DIGEST_LEN)) { + log_warn(LD_REND, "Received service descriptor for %s with incorrect " + "descriptor ID.", service_id); + goto err; + } + /* Decode/decrypt introduction points. */ if (intro_content) { int n_intro_points; @@ -1156,6 +1261,7 @@ rend_cache_store_v2_desc_as_client(const char *desc, e = tor_malloc_zero(sizeof(rend_cache_entry_t)); strmap_set_lc(rend_cache, key, e); } else { + rend_cache_decrement_allocation(rend_cache_entry_allocation(e)); rend_service_descriptor_free(e->parsed); tor_free(e->desc); } @@ -1164,6 +1270,7 @@ rend_cache_store_v2_desc_as_client(const char *desc, e->desc = tor_malloc_zero(encoded_size + 1); strlcpy(e->desc, desc, encoded_size + 1); e->len = encoded_size; + rend_cache_increment_allocation(rend_cache_entry_allocation(e)); log_debug(LD_REND,"Successfully stored rend desc '%s', len %d.", safe_str_client(service_id), (int)encoded_size); return RCS_OKAY; |