commit 8aa69a1b69b64185333fb1b6e74d55fc5e341fd8 Author: Nick Mathewson nickm@torproject.org Date: Mon Mar 13 15:38:20 2017 -0400

Refactor the directory spool implementation

The old implementation had duplicated code in a bunch of places, and it interspersed spool-management with resource management. The new implementation should make it easier to add new resource types and maintain the spooling code.

Closing ticket 21651. --- changes/new_spooling_backend | 7 + src/or/connection.c | 8 +- src/or/directory.c | 204 +++++++---- src/or/directory.h | 9 +- src/or/dirserv.c | 806 +++++++++++++++++++++-------------------- src/or/dirserv.h | 74 +++- src/or/microdesc.c | 12 - src/or/microdesc.h | 2 - src/or/or.h | 24 +- src/test/test_dir_handle_get.c | 17 +- 10 files changed, 646 insertions(+), 517 deletions(-)

diff --git a/changes/new_spooling_backend b/changes/new_spooling_backend new file mode 100644 index 0000000..a100688 --- /dev/null +++ b/changes/new_spooling_backend @@ -0,0 +1,7 @@ + o Code simplification and refactoring: + - The logic that directory caches use to spool request to clients, + serving them one part at a time so as not to allocate too much memory, + has been refactored for consistency. Previously there was a separate + spooling implementation per type of spoolable data. Now there + is one common spooling implementation, with extensible data types. + Closes ticket 21651. diff --git a/src/or/connection.c b/src/or/connection.c index 1882760..3c51df3 100644 --- a/src/or/connection.c +++ b/src/or/connection.c @@ -629,12 +629,12 @@ connection_free_(connection_t *conn) tor_free(dir_conn->requested_resource);

tor_zlib_free(dir_conn->zlib_state); - if (dir_conn->fingerprint_stack) { - SMARTLIST_FOREACH(dir_conn->fingerprint_stack, char *, cp, tor_free(cp)); - smartlist_free(dir_conn->fingerprint_stack); + if (dir_conn->spool) { + SMARTLIST_FOREACH(dir_conn->spool, spooled_resource_t *, spooled, + spooled_resource_free(spooled)); + smartlist_free(dir_conn->spool); }

- cached_dir_decref(dir_conn->cached_dir); rend_data_free(dir_conn->rend_data); if (dir_conn->guard_state) { /* Cancel before freeing, if it's still there. */ diff --git a/src/or/directory.c b/src/or/directory.c index e60952f..ee36a43 100644 --- a/src/or/directory.c +++ b/src/or/directory.c @@ -1368,7 +1368,7 @@ directory_initiate_command_rend(const tor_addr_port_t *or_addr_port, /** Return true iff anything we say on <b>conn</b> is being encrypted before * we send it to the client/server. */ int -connection_dir_is_encrypted(dir_connection_t *conn) +connection_dir_is_encrypted(const dir_connection_t *conn) { /* Right now it's sufficient to see if conn is or has been linked, since * the only thing it could be linked to is an edge connection on a @@ -3061,10 +3061,10 @@ handle_get_current_consensus(dir_connection_t *conn, const char *url = args->url; const int compressed = args->compressed; const time_t if_modified_since = args->if_modified_since; + int clear_spool = 0;

{ /* v3 network status fetch. */ - smartlist_t *dir_fps = smartlist_new(); long lifetime = NETWORKSTATUS_CACHE_LIFETIME;

networkstatus_t *v; @@ -3098,7 +3098,6 @@ handle_get_current_consensus(dir_connection_t *conn, if (v && !networkstatus_consensus_reasonably_live(v, now)) { write_http_status_line(conn, 404, "Consensus is too old"); warn_consensus_is_too_old(v, flavor, now); - smartlist_free(dir_fps); geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND); tor_free(flavor); goto done; @@ -3108,51 +3107,54 @@ handle_get_current_consensus(dir_connection_t *conn, !client_likes_consensus(v, want_fps)) { write_http_status_line(conn, 404, "Consensus not signed by sufficient " "number of requested authorities"); - smartlist_free(dir_fps); geoip_note_ns_response(GEOIP_REJECT_NOT_ENOUGH_SIGS); tor_free(flavor); goto done; }

+ conn->spool = smartlist_new(); + clear_spool = 1; { - char *fp = tor_malloc_zero(DIGEST_LEN); + spooled_resource_t *spooled; if (flavor) - strlcpy(fp, flavor, DIGEST_LEN); + spooled = spooled_resource_new(DIR_SPOOL_NETWORKSTATUS, + (uint8_t*)flavor, strlen(flavor)); + else + spooled = spooled_resource_new(DIR_SPOOL_NETWORKSTATUS, + NULL, 0); tor_free(flavor); - smartlist_add(dir_fps, fp); + smartlist_add(conn->spool, spooled); } lifetime = (v && v->fresh_until > now) ? v->fresh_until - now : 0;

- if (!smartlist_len(dir_fps)) { /* we failed to create/cache cp */ + if (!smartlist_len(conn->spool)) { /* we failed to create/cache cp */ write_http_status_line(conn, 503, "Network status object unavailable"); - smartlist_free(dir_fps); geoip_note_ns_response(GEOIP_REJECT_UNAVAILABLE); goto done; }

- if (!dirserv_remove_old_statuses(dir_fps, if_modified_since)) { + size_t size_guess = 0; + int n_expired = 0; + dirserv_spool_remove_missing_and_guess_size(conn, if_modified_since, + compressed, + &size_guess, + &n_expired); + + if (!smartlist_len(conn->spool) && !n_expired) { write_http_status_line(conn, 404, "Not found"); - SMARTLIST_FOREACH(dir_fps, char *, cp, tor_free(cp)); - smartlist_free(dir_fps); geoip_note_ns_response(GEOIP_REJECT_NOT_FOUND); goto done; - } else if (!smartlist_len(dir_fps)) { + } else if (!smartlist_len(conn->spool)) { write_http_status_line(conn, 304, "Not modified"); - SMARTLIST_FOREACH(dir_fps, char *, cp, tor_free(cp)); - smartlist_free(dir_fps); geoip_note_ns_response(GEOIP_REJECT_NOT_MODIFIED); goto done; }

- size_t dlen = dirserv_estimate_data_size(dir_fps, 0, compressed); - if (global_write_bucket_low(TO_CONN(conn), dlen, 2)) { + if (global_write_bucket_low(TO_CONN(conn), size_guess, 2)) { log_debug(LD_DIRSERV, "Client asked for network status lists, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); - SMARTLIST_FOREACH(dir_fps, char *, fp, tor_free(fp)); - smartlist_free(dir_fps); - geoip_note_ns_response(GEOIP_REJECT_BUSY); goto done; } @@ -3166,25 +3168,27 @@ handle_get_current_consensus(dir_connection_t *conn, /* Note that a request for a network status has started, so that we * can measure the download time later on. */ if (conn->dirreq_id) - geoip_start_dirreq(conn->dirreq_id, dlen, DIRREQ_TUNNELED); + geoip_start_dirreq(conn->dirreq_id, size_guess, DIRREQ_TUNNELED); else - geoip_start_dirreq(TO_CONN(conn)->global_identifier, dlen, + geoip_start_dirreq(TO_CONN(conn)->global_identifier, size_guess, DIRREQ_DIRECT); }

+ clear_spool = 0; write_http_response_header(conn, -1, compressed, - smartlist_len(dir_fps) == 1 ? lifetime : 0); - conn->fingerprint_stack = dir_fps; + smartlist_len(conn->spool) == 1 ? lifetime : 0); if (! compressed) conn->zlib_state = tor_zlib_new(0, ZLIB_METHOD, HIGH_COMPRESSION);

/* Prime the connection with some data. */ - conn->dir_spool_src = DIR_SPOOL_NETWORKSTATUS; connection_dirserv_flushed_some(conn); goto done; }

done: + if (clear_spool) { + dir_conn_clear_spool(conn); + } return 0; }

@@ -3302,43 +3306,45 @@ handle_get_microdesc(dir_connection_t *conn, const get_handler_args_t *args) { const char *url = args->url; const int compressed = args->compressed; + int clear_spool = 1; { - smartlist_t *fps = smartlist_new(); + conn->spool = smartlist_new();

- dir_split_resource_into_fingerprints(url+strlen("/tor/micro/d/"), - fps, NULL, + dir_split_resource_into_spoolable(url+strlen("/tor/micro/d/"), + DIR_SPOOL_MICRODESC, + conn->spool, NULL, DSR_DIGEST256|DSR_BASE64|DSR_SORT_UNIQ);

- if (!dirserv_have_any_microdesc(fps)) { + size_t size_guess = 0; + dirserv_spool_remove_missing_and_guess_size(conn, 0, compressed, + &size_guess, NULL); + if (smartlist_len(conn->spool) == 0) { write_http_status_line(conn, 404, "Not found"); - SMARTLIST_FOREACH(fps, char *, fp, tor_free(fp)); - smartlist_free(fps); goto done; } - size_t dlen = dirserv_estimate_microdesc_size(fps, compressed); - if (global_write_bucket_low(TO_CONN(conn), dlen, 2)) { + if (global_write_bucket_low(TO_CONN(conn), size_guess, 2)) { log_info(LD_DIRSERV, "Client asked for server descriptors, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); - SMARTLIST_FOREACH(fps, char *, fp, tor_free(fp)); - smartlist_free(fps); goto done; }

+ clear_spool = 0; write_http_response_header(conn, -1, compressed, MICRODESC_CACHE_LIFETIME); - conn->dir_spool_src = DIR_SPOOL_MICRODESC; - conn->fingerprint_stack = fps;

if (compressed) conn->zlib_state = tor_zlib_new(1, ZLIB_METHOD, - choose_compression_level(dlen)); + choose_compression_level(size_guess));

connection_dirserv_flushed_some(conn); goto done; }

done: + if (clear_spool) { + dir_conn_clear_spool(conn); + } return 0; }

@@ -3350,69 +3356,88 @@ handle_get_descriptor(dir_connection_t *conn, const get_handler_args_t *args) const char *url = args->url; const int compressed = args->compressed; const or_options_t *options = get_options(); + int clear_spool = 1; if (!strcmpstart(url,"/tor/server/") || (!options->BridgeAuthoritativeDir && !options->BridgeRelay && !strcmpstart(url,"/tor/extra/"))) { - size_t dlen; int res; - const char *msg; + const char *msg = NULL; int cache_lifetime = 0; int is_extra = !strcmpstart(url,"/tor/extra/"); url += is_extra ? strlen("/tor/extra/") : strlen("/tor/server/"); - conn->fingerprint_stack = smartlist_new(); - res = dirserv_get_routerdesc_fingerprints(conn->fingerprint_stack, url, - &msg, - !connection_dir_is_encrypted(conn), - is_extra); - - if (!strcmpstart(url, "fp/")) { - if (smartlist_len(conn->fingerprint_stack) == 1) - cache_lifetime = ROUTERDESC_CACHE_LIFETIME; - } else if (!strcmpstart(url, "authority")) { - cache_lifetime = ROUTERDESC_CACHE_LIFETIME; - } else if (!strcmpstart(url, "all")) { - cache_lifetime = FULL_DIR_CACHE_LIFETIME; - } else if (!strcmpstart(url, "d/")) { - if (smartlist_len(conn->fingerprint_stack) == 1) - cache_lifetime = ROUTERDESC_BY_DIGEST_CACHE_LIFETIME; - } - if (!strcmpstart(url, "d/")) - conn->dir_spool_src = + dir_spool_source_t source; + time_t publish_cutoff = 0; + if (!strcmpstart(url, "d/")) { + source = is_extra ? DIR_SPOOL_EXTRA_BY_DIGEST : DIR_SPOOL_SERVER_BY_DIGEST; - else - conn->dir_spool_src = + } else { + source = is_extra ? DIR_SPOOL_EXTRA_BY_FP : DIR_SPOOL_SERVER_BY_FP; + /* We only want to apply a publish cutoff when we're requesting + * resources by fingerprint. */ + publish_cutoff = time(NULL) - ROUTER_MAX_AGE_TO_PUBLISH; + }

- if (!dirserv_have_any_serverdesc(conn->fingerprint_stack, - conn->dir_spool_src)) { - res = -1; - msg = "Not found"; + conn->spool = smartlist_new(); + res = dirserv_get_routerdesc_spool(conn->spool, url, + source, + connection_dir_is_encrypted(conn), + &msg); + + if (!strcmpstart(url, "all")) { + cache_lifetime = FULL_DIR_CACHE_LIFETIME; + } else if (smartlist_len(conn->spool) == 1) { + cache_lifetime = ROUTERDESC_BY_DIGEST_CACHE_LIFETIME; }

- if (res < 0) + size_t size_guess = 0; + int n_expired = 0; + dirserv_spool_remove_missing_and_guess_size(conn, publish_cutoff, + compressed, &size_guess, + &n_expired); + + /* If we are the bridge authority and the descriptor is a bridge + * descriptor, remember that we served this descriptor for desc stats. */ + /* XXXX it's a bit of a kludge to have this here. */ + if (get_options()->BridgeAuthoritativeDir && + source == DIR_SPOOL_SERVER_BY_FP) { + SMARTLIST_FOREACH_BEGIN(conn->spool, spooled_resource_t *, spooled) { + const routerinfo_t *router = + router_get_by_id_digest((const char *)spooled->digest); + /* router can be NULL here when the bridge auth is asked for its own + * descriptor. */ + if (router && router->purpose == ROUTER_PURPOSE_BRIDGE) + rep_hist_note_desc_served(router->cache_info.identity_digest); + } SMARTLIST_FOREACH_END(spooled); + } + + if (res < 0 || size_guess == 0 || smartlist_len(conn->spool) == 0) { + if (msg == NULL) + msg = "Not found"; write_http_status_line(conn, 404, msg); - else { - dlen = dirserv_estimate_data_size(conn->fingerprint_stack, - 1, compressed); - if (global_write_bucket_low(TO_CONN(conn), dlen, 2)) { + } else { + if (global_write_bucket_low(TO_CONN(conn), size_guess, 2)) { log_info(LD_DIRSERV, "Client asked for server descriptors, but we've been " "writing too many bytes lately. Sending 503 Dir busy."); write_http_status_line(conn, 503, "Directory busy, try again later"); - conn->dir_spool_src = DIR_SPOOL_NONE; + dir_conn_clear_spool(conn); goto done; } write_http_response_header(conn, -1, compressed, cache_lifetime); if (compressed) conn->zlib_state = tor_zlib_new(1, ZLIB_METHOD, - choose_compression_level(dlen)); + choose_compression_level(size_guess)); + clear_spool = 0; /* Prime the connection with some data. */ connection_dirserv_flushed_some(conn); } goto done; } done: - return 0; + if (clear_spool) + dir_conn_clear_spool(conn); + return 0; }

/** Helper function for GET /tor/keys/... @@ -3936,7 +3961,7 @@ connection_dir_finished_flushing(dir_connection_t *conn) conn->base_.state = DIR_CONN_STATE_CLIENT_READING; return 0; case DIR_CONN_STATE_SERVER_WRITING: - if (conn->dir_spool_src != DIR_SPOOL_NONE) { + if (conn->spool) { log_warn(LD_BUG, "Emptied a dirserv buffer, but it's still spooling!"); connection_mark_for_close(TO_CONN(conn)); } else { @@ -4619,3 +4644,34 @@ dir_split_resource_into_fingerprints(const char *resource, return 0; }

+/** As dir_split_resource_into_fingerprints, but instead fills + * <b>spool_out</b> with a list of spoolable_resource_t for the resource + * identified through <b>source</b>. */ +int +dir_split_resource_into_spoolable(const char *resource, + dir_spool_source_t source, + smartlist_t *spool_out, + int *compressed_out, + int flags) +{ + smartlist_t *fingerprints = smartlist_new(); + + tor_assert(flags & (DSR_HEX|DSR_BASE64)); + const size_t digest_len = + (flags & DSR_DIGEST256) ? DIGEST256_LEN : DIGEST_LEN; + + int r = dir_split_resource_into_fingerprints(resource, fingerprints, + compressed_out, flags); + /* This is not a very efficient implementation XXXX */ + SMARTLIST_FOREACH_BEGIN(fingerprints, uint8_t *, digest) { + spooled_resource_t *spooled = + spooled_resource_new(source, digest, digest_len); + if (spooled) + smartlist_add(spool_out, spooled); + tor_free(digest); + } SMARTLIST_FOREACH_END(digest); + + smartlist_free(fingerprints); + return r; +} + diff --git a/src/or/directory.h b/src/or/directory.h index 8be1f8e..a45a0aa 100644 --- a/src/or/directory.h +++ b/src/or/directory.h @@ -66,7 +66,7 @@ void directory_initiate_command_routerstatus_rend(const routerstatus_t *status, int parse_http_response(const char *headers, int *code, time_t *date, compress_method_t *compression, char **response);

-int connection_dir_is_encrypted(dir_connection_t *conn); +int connection_dir_is_encrypted(const dir_connection_t *conn); int connection_dir_reached_eof(dir_connection_t *conn); int connection_dir_process_inbuf(dir_connection_t *conn); int connection_dir_finished_flushing(dir_connection_t *conn); @@ -88,7 +88,12 @@ void directory_initiate_command(const tor_addr_t *or_addr, uint16_t or_port, int dir_split_resource_into_fingerprints(const char *resource, smartlist_t *fp_out, int *compressed_out, int flags); - +enum dir_spool_source_t; +int dir_split_resource_into_spoolable(const char *resource, + enum dir_spool_source_t source, + smartlist_t *spool_out, + int *compressed_out, + int flags); int dir_split_resource_into_fingerprint_pairs(const char *res, smartlist_t *pairs_out); char *directory_dump_request_log(void); diff --git a/src/or/dirserv.c b/src/or/dirserv.c index 74617ff..bf01dce 100644 --- a/src/or/dirserv.c +++ b/src/or/dirserv.c @@ -81,14 +81,23 @@ dirserv_get_status_impl(const char *fp, const char *nickname, int severity); static void clear_cached_dir(cached_dir_t *d); static const signed_descriptor_t *get_signed_descriptor_by_fp( - const char *fp, - int extrainfo, - time_t publish_cutoff); + const uint8_t *fp, + int extrainfo); static was_router_added_t dirserv_add_extrainfo(extrainfo_t *ei, const char **msg); static uint32_t dirserv_get_bandwidth_for_router_kb(const routerinfo_t *ri); static uint32_t dirserv_get_credible_bandwidth_kb(const routerinfo_t *ri);

+static int spooled_resource_lookup_body(const spooled_resource_t *spooled, + int conn_is_encrypted, + const uint8_t **body_out, + size_t *size_out, + time_t *published_out); +static cached_dir_t *spooled_resource_lookup_cached_dir( + const spooled_resource_t *spooled, + time_t *published_out); +static cached_dir_t *lookup_cached_dir_by_fp(const uint8_t *fp); + /************** Fingerprint handling code ************/

/* 1 Historically used to indicate Named */ @@ -3037,58 +3046,61 @@ dirserv_generate_networkstatus_vote_obj(crypto_pk_t *private_key, * requests, adds identity digests. */ int -dirserv_get_routerdesc_fingerprints(smartlist_t *fps_out, const char *key, - const char **msg, int for_unencrypted_conn, - int is_extrainfo) +dirserv_get_routerdesc_spool(smartlist_t *spool_out, + const char *key, + dir_spool_source_t source, + int conn_is_encrypted, + const char **msg_out) { - int by_id = 1; - *msg = NULL; + *msg_out = NULL;

if (!strcmp(key, "all")) { - routerlist_t *rl = router_get_routerlist(); - SMARTLIST_FOREACH(rl->routers, routerinfo_t *, r, - smartlist_add(fps_out, - tor_memdup(r->cache_info.identity_digest, DIGEST_LEN))); - /* Treat "all" requests as if they were unencrypted */ - for_unencrypted_conn = 1; + const routerlist_t *rl = router_get_routerlist(); + SMARTLIST_FOREACH_BEGIN(rl->routers, const routerinfo_t *, r) { + spooled_resource_t *spooled; + spooled = spooled_resource_new(source, + (const uint8_t *)r->cache_info.identity_digest, + DIGEST_LEN); + /* Treat "all" requests as if they were unencrypted */ + conn_is_encrypted = 0; + smartlist_add(spool_out, spooled); + } SMARTLIST_FOREACH_END(r); } else if (!strcmp(key, "authority")) { const routerinfo_t *ri = router_get_my_routerinfo(); if (ri) - smartlist_add(fps_out, - tor_memdup(ri->cache_info.identity_digest, DIGEST_LEN)); + smartlist_add(spool_out, + spooled_resource_new(source, + (const uint8_t *)ri->cache_info.identity_digest, + DIGEST_LEN)); } else if (!strcmpstart(key, "d/")) { - by_id = 0; key += strlen("d/"); - dir_split_resource_into_fingerprints(key, fps_out, NULL, - DSR_HEX|DSR_SORT_UNIQ); + dir_split_resource_into_spoolable(key, source, spool_out, NULL, + DSR_HEX|DSR_SORT_UNIQ); } else if (!strcmpstart(key, "fp/")) { key += strlen("fp/"); - dir_split_resource_into_fingerprints(key, fps_out, NULL, - DSR_HEX|DSR_SORT_UNIQ); + dir_split_resource_into_spoolable(key, source, spool_out, NULL, + DSR_HEX|DSR_SORT_UNIQ); } else { - *msg = "Key not recognized"; + *msg_out = "Not found"; return -1; }

- if (for_unencrypted_conn) { + if (! conn_is_encrypted) { /* Remove anything that insists it not be sent unencrypted. */ - SMARTLIST_FOREACH_BEGIN(fps_out, char *, cp) { - const signed_descriptor_t *sd; - if (by_id) - sd = get_signed_descriptor_by_fp(cp,is_extrainfo,0); - else if (is_extrainfo) - sd = extrainfo_get_by_descriptor_digest(cp); - else - sd = router_get_by_descriptor_digest(cp); - if (sd && !sd->send_unencrypted) { - tor_free(cp); - SMARTLIST_DEL_CURRENT(fps_out, cp); - } - } SMARTLIST_FOREACH_END(cp); + SMARTLIST_FOREACH_BEGIN(spool_out, spooled_resource_t *, spooled) { + const uint8_t *body = NULL; + size_t bodylen = 0; + int r = spooled_resource_lookup_body(spooled, conn_is_encrypted, + &body, &bodylen, NULL); + if (r < 0 || body == NULL || bodylen == 0) { + SMARTLIST_DEL_CURRENT(spool_out, spooled); + spooled_resource_free(spooled); + } + } SMARTLIST_FOREACH_END(spooled); }

- if (!smartlist_len(fps_out)) { - *msg = "Servers unavailable"; + if (!smartlist_len(spool_out)) { + *msg_out = "Servers unavailable"; return -1; } return 0; @@ -3352,414 +3364,438 @@ dirserv_test_reachability(time_t now) ctr = (ctr + 1) % REACHABILITY_MODULO_PER_TEST; /* increment ctr */ }

-/** Given a fingerprint <b>fp</b> which is either set if we're looking for a - * v2 status, or zeroes if we're looking for a v3 status, or a NUL-padded - * flavor name if we want a flavored v3 status, return a pointer to the - * appropriate cached dir object, or NULL if there isn't one available. */ -static cached_dir_t * -lookup_cached_dir_by_fp(const char *fp) +/* ========== + * Spooling code. + * ========== */ + +spooled_resource_t * +spooled_resource_new(dir_spool_source_t source, + const uint8_t *digest, size_t digestlen) { - cached_dir_t *d = NULL; - if (tor_digest_is_zero(fp) && cached_consensuses) { - d = strmap_get(cached_consensuses, "ns"); - } else if (memchr(fp, '\0', DIGEST_LEN) && cached_consensuses && - (d = strmap_get(cached_consensuses, fp))) { - /* this here interface is a nasty hack XXXX */; + spooled_resource_t *spooled = tor_malloc_zero(sizeof(spooled_resource_t)); + spooled->spool_source = source; + switch (source) { + case DIR_SPOOL_NETWORKSTATUS: + spooled->spool_eagerly = 0; + break; + case DIR_SPOOL_SERVER_BY_DIGEST: + case DIR_SPOOL_SERVER_BY_FP: + case DIR_SPOOL_EXTRA_BY_DIGEST: + case DIR_SPOOL_EXTRA_BY_FP: + case DIR_SPOOL_MICRODESC: + default: + spooled->spool_eagerly = 1; + break; } - return d; + tor_assert(digestlen <= sizeof(spooled->digest)); + if (digest) + memcpy(spooled->digest, digest, digestlen); + return spooled; }

-/** Remove from <b>fps</b> every networkstatus key where both - * a) we have a networkstatus document and - * b) it is not newer than <b>cutoff</b>. - * - * Return 1 if any items were present at all; else return 0. - */ -int -dirserv_remove_old_statuses(smartlist_t *fps, time_t cutoff) +/** Release all storage held by <b>spooled</b>. */ +void +spooled_resource_free(spooled_resource_t *spooled) { - int found_any = 0; - SMARTLIST_FOREACH_BEGIN(fps, char *, digest) { - cached_dir_t *d = lookup_cached_dir_by_fp(digest); - if (!d) - continue; - found_any = 1; - if (d->published <= cutoff) { - tor_free(digest); - SMARTLIST_DEL_CURRENT(fps, digest); - } - } SMARTLIST_FOREACH_END(digest); - - return found_any; -} + if (spooled == NULL) + return;

-/** Return the cache-info for identity fingerprint <b>fp</b>, or - * its extra-info document if <b>extrainfo</b> is true. Return - * NULL if not found or if the descriptor is older than - * <b>publish_cutoff</b>. */ -static const signed_descriptor_t * -get_signed_descriptor_by_fp(const char *fp, int extrainfo, - time_t publish_cutoff) -{ - if (router_digest_is_me(fp)) { - if (extrainfo) - return &(router_get_my_extrainfo()->cache_info); - else - return &(router_get_my_routerinfo()->cache_info); - } else { - const routerinfo_t *ri = router_get_by_id_digest(fp); - if (ri && - ri->cache_info.published_on > publish_cutoff) { - if (extrainfo) - return extrainfo_get_by_descriptor_digest( - ri->cache_info.extra_info_digest); - else - return &ri->cache_info; - } + if (spooled->cached_dir_ref) { + cached_dir_decref(spooled->cached_dir_ref); } - return NULL; -}

-/** Return true iff we have any of the documents (extrainfo or routerdesc) - * specified by the fingerprints in <b>fps</b> and <b>spool_src</b>. Used to - * decide whether to send a 404. */ -int -dirserv_have_any_serverdesc(smartlist_t *fps, int spool_src) -{ - time_t publish_cutoff = time(NULL)-ROUTER_MAX_AGE_TO_PUBLISH; - SMARTLIST_FOREACH_BEGIN(fps, const char *, fp) { - switch (spool_src) - { - case DIR_SPOOL_EXTRA_BY_DIGEST: - if (extrainfo_get_by_descriptor_digest(fp)) return 1; - break; - case DIR_SPOOL_SERVER_BY_DIGEST: - if (router_get_by_descriptor_digest(fp)) return 1; - break; - case DIR_SPOOL_EXTRA_BY_FP: - case DIR_SPOOL_SERVER_BY_FP: - if (get_signed_descriptor_by_fp(fp, - spool_src == DIR_SPOOL_EXTRA_BY_FP, publish_cutoff)) - return 1; - break; - } - } SMARTLIST_FOREACH_END(fp); - return 0; + tor_free(spooled); }

-/** Return true iff any of the 256-bit elements in <b>fps</b> is the digest of - * a microdescriptor we have. */ -int -dirserv_have_any_microdesc(const smartlist_t *fps) +/** When spooling data from a cached_dir_t object, we always add + * at least this much. */ +#define DIRSERV_CACHED_DIR_CHUNK_SIZE 8192 + +/** Return an compression ratio for compressing objects from <b>source</b>. + */ +static double +estimate_compression_ratio(dir_spool_source_t source) { - microdesc_cache_t *cache = get_microdesc_cache(); - SMARTLIST_FOREACH(fps, const char *, fp, - if (microdesc_cache_lookup_by_digest256(cache, fp)) - return 1); - return 0; + /* We should put in better estimates here, depending on the number of + objects and their type */ + (void) source; + return 0.5; }

-/** Return an approximate estimate of the number of bytes that will - * be needed to transmit the server descriptors (if is_serverdescs -- - * they can be either d/ or fp/ queries) or networkstatus objects (if - * !is_serverdescs) listed in <b>fps</b>. If <b>compressed</b> is set, - * we guess how large the data will be after compression. +/** Return an estimated number of bytes needed for transmitting the + * resource in <b>spooled</b> on <b>conn</b> * - * The return value is an estimate; it might be larger or smaller. - **/ -size_t -dirserv_estimate_data_size(smartlist_t *fps, int is_serverdescs, - int compressed) -{ - size_t result; - tor_assert(fps); - if (is_serverdescs) { - int n = smartlist_len(fps); - const routerinfo_t *me = router_get_my_routerinfo(); - result = (me?me->cache_info.signed_descriptor_len:2048) * n; - if (compressed) - result /= 2; /* observed compressibility is between 35 and 55%. */ + * As a convenient side-effect, set *<b>published_out</b> to the resource's + * publication time. + */ +static size_t +spooled_resource_estimate_size(const spooled_resource_t *spooled, + dir_connection_t *conn, + int compressed, + time_t *published_out) +{ + if (spooled->spool_eagerly) { + const uint8_t *body = NULL; + size_t bodylen = 0; + int r = spooled_resource_lookup_body(spooled, + connection_dir_is_encrypted(conn), + &body, &bodylen, + published_out); + if (r == -1 || body == NULL || bodylen == 0) + return 0; + if (compressed) { + double ratio = estimate_compression_ratio(spooled->spool_source); + bodylen = (size_t)(bodylen * ratio); + } + return bodylen; } else { - result = 0; - SMARTLIST_FOREACH(fps, const char *, digest, { - cached_dir_t *dir = lookup_cached_dir_by_fp(digest); - if (dir) - result += compressed ? dir->dir_z_len : dir->dir_len; - }); + cached_dir_t *cached; + if (spooled->cached_dir_ref) { + cached = spooled->cached_dir_ref; + } else { + cached = spooled_resource_lookup_cached_dir(spooled, + published_out); + } + if (cached == NULL) { + return 0; + } + size_t result = compressed ? cached->dir_z_len : cached->dir_len; + return result; } - return result; }

-/** Given a list of microdescriptor hashes, guess how many bytes will be - * needed to transmit them, and return the guess. */ -size_t -dirserv_estimate_microdesc_size(const smartlist_t *fps, int compressed) -{ - size_t result = smartlist_len(fps) * microdesc_average_size(NULL); - if (compressed) - result /= 2; - return result; -} +/** Return code for spooled_resource_flush_some */ +typedef enum { + SRFS_ERR = -1, + SRFS_MORE = 0, + SRFS_DONE +} spooled_resource_flush_status_t;

-/** When we're spooling data onto our outbuf, add more whenever we dip - * below this threshold. */ -#define DIRSERV_BUFFER_MIN 16384 +/** Flush some or all of the bytes from <b>spooled</b> onto <b>conn</b>. + * Return SRFS_ERR on error, SRFS_MORE if there are more bytes to flush from + * this spooled resource, or SRFS_DONE if we are done flushing this spooled + * resource. + */ +static spooled_resource_flush_status_t +spooled_resource_flush_some(spooled_resource_t *spooled, + dir_connection_t *conn) +{ + if (spooled->spool_eagerly) { + /* Spool_eagerly resources are sent all-at-once. */ + const uint8_t *body = NULL; + size_t bodylen = 0; + int r = spooled_resource_lookup_body(spooled, + connection_dir_is_encrypted(conn), + &body, &bodylen, NULL); + if (r == -1 || body == NULL || bodylen == 0) { + /* Absent objects count as "done". */ + return SRFS_DONE; + } + if (conn->zlib_state) { + connection_write_to_buf_zlib((const char*)body, bodylen, conn, 0); + } else { + connection_write_to_buf((const char*)body, bodylen, TO_CONN(conn)); + } + return SRFS_DONE; + } else { + cached_dir_t *cached = spooled->cached_dir_ref; + if (cached == NULL) { + /* The cached_dir_t hasn't been materialized yet. So let's look it up. */ + cached = spooled->cached_dir_ref = + spooled_resource_lookup_cached_dir(spooled, NULL); + if (!cached) { + /* Absent objects count as done. */ + return SRFS_DONE; + } + ++cached->refcnt; + tor_assert_nonfatal(spooled->cached_dir_offset == 0); + }

-/** Spooling helper: called when we have no more data to spool to <b>conn</b>. - * Flushes any remaining data to be (un)compressed, and changes the spool - * source to NONE. Returns 0 on success, negative on failure. */ -static int -connection_dirserv_finish_spooling(dir_connection_t *conn) -{ - if (conn->zlib_state) { - connection_write_to_buf_zlib("", 0, conn, 1); - tor_zlib_free(conn->zlib_state); - conn->zlib_state = NULL; + /* How many bytes left to flush? */ + int64_t remaining = 0; + remaining = cached->dir_z_len - spooled->cached_dir_offset; + if (BUG(remaining < 0)) + return SRFS_ERR; + ssize_t bytes = MIN(DIRSERV_CACHED_DIR_CHUNK_SIZE, remaining); + if (conn->zlib_state) { + connection_write_to_buf_zlib(cached->dir_z + spooled->cached_dir_offset, + bytes, conn, 0); + } else { + connection_write_to_buf(cached->dir_z + spooled->cached_dir_offset, + bytes, TO_CONN(conn)); + } + spooled->cached_dir_offset += bytes; + if (spooled->cached_dir_offset >= (off_t)cached->dir_z_len) { + return SRFS_DONE; + } else { + return SRFS_MORE; + } } - conn->dir_spool_src = DIR_SPOOL_NONE; - return 0; }

-/** Spooling helper: called when we're sending a bunch of server descriptors, - * and the outbuf has become too empty. Pulls some entries from - * fingerprint_stack, and writes the corresponding servers onto outbuf. If we - * run out of entries, flushes the zlib state and sets the spool source to - * NONE. Returns 0 on success, negative on failure. +/** Helper: find the cached_dir_t for a spooled_resource_t, for + * sending it to <b>conn</b>. Set *<b>published_out</b>, if provided, + * to the published time of the cached_dir_t. + * + * DOES NOT increase the reference count on the result. Callers must do that + * themselves if they mean to hang on to it. */ +static cached_dir_t * +spooled_resource_lookup_cached_dir(const spooled_resource_t *spooled, + time_t *published_out) +{ + tor_assert(spooled->spool_eagerly == 0); + cached_dir_t *d = lookup_cached_dir_by_fp(spooled->digest); + if (d != NULL) { + if (published_out) + *published_out = d->published; + } + return d; +} + +/** Helper: Look up the body for an eagerly-served spooled_resource. If + * <b>conn_is_encrypted</b> is false, don't look up any resource that + * shouldn't be sent over an unencrypted connection. On success, set + * <b>body_out</b>, <b>size_out</b>, and <b>published_out</b> to refer + * to the resource's body, size, and publication date, and return 0. + * On failure return -1. */ static int -connection_dirserv_add_servers_to_outbuf(dir_connection_t *conn) +spooled_resource_lookup_body(const spooled_resource_t *spooled, + int conn_is_encrypted, + const uint8_t **body_out, + size_t *size_out, + time_t *published_out) { - int by_fp = (conn->dir_spool_src == DIR_SPOOL_SERVER_BY_FP || - conn->dir_spool_src == DIR_SPOOL_EXTRA_BY_FP); - int extra = (conn->dir_spool_src == DIR_SPOOL_EXTRA_BY_FP || - conn->dir_spool_src == DIR_SPOOL_EXTRA_BY_DIGEST); - time_t publish_cutoff = time(NULL)-ROUTER_MAX_AGE_TO_PUBLISH; + tor_assert(spooled->spool_eagerly == 1);

- const or_options_t *options = get_options(); + const signed_descriptor_t *sd = NULL;

- while (smartlist_len(conn->fingerprint_stack) && - connection_get_outbuf_len(TO_CONN(conn)) < DIRSERV_BUFFER_MIN) { - const char *body; - char *fp = smartlist_pop_last(conn->fingerprint_stack); - const signed_descriptor_t *sd = NULL; - if (by_fp) { - sd = get_signed_descriptor_by_fp(fp, extra, publish_cutoff); - } else { - sd = extra ? extrainfo_get_by_descriptor_digest(fp) - : router_get_by_descriptor_digest(fp); + switch (spooled->spool_source) { + case DIR_SPOOL_EXTRA_BY_FP: { + sd = get_signed_descriptor_by_fp(spooled->digest, 1); + break; } - tor_free(fp); - if (!sd) - continue; - if (!connection_dir_is_encrypted(conn) && !sd->send_unencrypted) { - /* we did this check once before (so we could have an accurate size - * estimate and maybe send a 404 if somebody asked for only bridges on a - * connection), but we need to do it again in case a previously - * unknown bridge descriptor has shown up between then and now. */ - continue; + case DIR_SPOOL_SERVER_BY_FP: { + sd = get_signed_descriptor_by_fp(spooled->digest, 0); + break; } - - /** If we are the bridge authority and the descriptor is a bridge - * descriptor, remember that we served this descriptor for desc stats. */ - if (options->BridgeAuthoritativeDir && by_fp) { - const routerinfo_t *router = - router_get_by_id_digest(sd->identity_digest); - /* router can be NULL here when the bridge auth is asked for its own - * descriptor. */ - if (router && router->purpose == ROUTER_PURPOSE_BRIDGE) - rep_hist_note_desc_served(sd->identity_digest); + case DIR_SPOOL_SERVER_BY_DIGEST: { + sd = router_get_by_descriptor_digest((const char *)spooled->digest); + break; } - body = signed_descriptor_get_body(sd); - if (conn->zlib_state) { - int last = ! smartlist_len(conn->fingerprint_stack); - connection_write_to_buf_zlib(body, sd->signed_descriptor_len, conn, - last); - if (last) { - tor_zlib_free(conn->zlib_state); - conn->zlib_state = NULL; + case DIR_SPOOL_EXTRA_BY_DIGEST: { + sd = extrainfo_get_by_descriptor_digest((const char *)spooled->digest); + break; + } + case DIR_SPOOL_MICRODESC: { + microdesc_t *md = microdesc_cache_lookup_by_digest256( + get_microdesc_cache(), + (const char *)spooled->digest); + if (! md || ! md->body) { + return -1; } - } else { - connection_write_to_buf(body, - sd->signed_descriptor_len, - TO_CONN(conn)); + *body_out = (const uint8_t *)md->body; + *size_out = md->bodylen; + if (published_out) + *published_out = TIME_MAX; + return 0; } + case DIR_SPOOL_NETWORKSTATUS: + default: + /* LCOV_EXCL_START */ + tor_assert_nonfatal_unreached(); + return -1; + /* LCOV_EXCL_STOP */ }

- if (!smartlist_len(conn->fingerprint_stack)) { - /* We just wrote the last one; finish up. */ - if (conn->zlib_state) { - connection_write_to_buf_zlib("", 0, conn, 1); - tor_zlib_free(conn->zlib_state); - conn->zlib_state = NULL; - } - conn->dir_spool_src = DIR_SPOOL_NONE; - smartlist_free(conn->fingerprint_stack); - conn->fingerprint_stack = NULL; - } - return 0; -} + /* If we get here, then we tried to set "sd" to a signed_descriptor_t. */

-/** Spooling helper: called when we're sending a bunch of microdescriptors, - * and the outbuf has become too empty. Pulls some entries from - * fingerprint_stack, and writes the corresponding microdescs onto outbuf. If - * we run out of entries, flushes the zlib state and sets the spool source to - * NONE. Returns 0 on success, negative on failure. - */ -static int -connection_dirserv_add_microdescs_to_outbuf(dir_connection_t *conn) -{ - microdesc_cache_t *cache = get_microdesc_cache(); - while (smartlist_len(conn->fingerprint_stack) && - connection_get_outbuf_len(TO_CONN(conn)) < DIRSERV_BUFFER_MIN) { - char *fp256 = smartlist_pop_last(conn->fingerprint_stack); - microdesc_t *md = microdesc_cache_lookup_by_digest256(cache, fp256); - tor_free(fp256); - if (!md || !md->body) - continue; - if (conn->zlib_state) { - int last = !smartlist_len(conn->fingerprint_stack); - connection_write_to_buf_zlib(md->body, md->bodylen, conn, last); - if (last) { - tor_zlib_free(conn->zlib_state); - conn->zlib_state = NULL; - } - } else { - connection_write_to_buf(md->body, md->bodylen, TO_CONN(conn)); - } + if (sd == NULL) { + return -1; } - if (!smartlist_len(conn->fingerprint_stack)) { - if (conn->zlib_state) { - connection_write_to_buf_zlib("", 0, conn, 1); - tor_zlib_free(conn->zlib_state); - conn->zlib_state = NULL; - } - conn->dir_spool_src = DIR_SPOOL_NONE; - smartlist_free(conn->fingerprint_stack); - conn->fingerprint_stack = NULL; + if (sd->send_unencrypted == 0 && ! conn_is_encrypted) { + /* we did this check once before (so we could have an accurate size + * estimate and maybe send a 404 if somebody asked for only bridges on + * a connection), but we need to do it again in case a previously + * unknown bridge descriptor has shown up between then and now. */ + return -1; } + *body_out = (const uint8_t *) signed_descriptor_get_body(sd); + *size_out = sd->signed_descriptor_len; + if (published_out) + *published_out = sd->published_on; return 0; }

-/** Spooling helper: Called when we're sending a directory or networkstatus, - * and the outbuf has become too empty. Pulls some bytes from - * <b>conn</b>->cached_dir->dir_z, uncompresses them if appropriate, and - * puts them on the outbuf. If we run out of entries, flushes the zlib state - * and sets the spool source to NONE. Returns 0 on success, negative on - * failure. */ -static int -connection_dirserv_add_dir_bytes_to_outbuf(dir_connection_t *conn) -{ - ssize_t bytes; - int64_t remaining; - - bytes = DIRSERV_BUFFER_MIN - connection_get_outbuf_len(TO_CONN(conn)); - tor_assert(bytes > 0); - tor_assert(conn->cached_dir); - if (bytes < 8192) - bytes = 8192; - remaining = conn->cached_dir->dir_z_len - conn->cached_dir_offset; - if (BUG(remaining < 0)) { - remaining = 0; - } - if (bytes > remaining) { - bytes = (ssize_t) remaining; - if (BUG(bytes < 0)) - return -1; +/** Given a fingerprint <b>fp</b> which is either set if we're looking for a + * v2 status, or zeroes if we're looking for a v3 status, or a NUL-padded + * flavor name if we want a flavored v3 status, return a pointer to the + * appropriate cached dir object, or NULL if there isn't one available. */ +static cached_dir_t * +lookup_cached_dir_by_fp(const uint8_t *fp) +{ + cached_dir_t *d = NULL; + if (tor_digest_is_zero((const char *)fp) && cached_consensuses) { + d = strmap_get(cached_consensuses, "ns"); + } else if (memchr(fp, '\0', DIGEST_LEN) && cached_consensuses) { + /* this here interface is a nasty hack: we're shoving a flavor into + * a digest field. */ + d = strmap_get(cached_consensuses, (const char *)fp); } + return d; +}

- if (conn->zlib_state) { - connection_write_to_buf_zlib( - conn->cached_dir->dir_z + conn->cached_dir_offset, - bytes, conn, bytes == remaining); - } else { - connection_write_to_buf(conn->cached_dir->dir_z + conn->cached_dir_offset, - bytes, TO_CONN(conn)); - } - conn->cached_dir_offset += bytes; - if (conn->cached_dir_offset >= (off_t)conn->cached_dir->dir_z_len) { - /* We just wrote the last one; finish up. */ - connection_dirserv_finish_spooling(conn); - cached_dir_decref(conn->cached_dir); - conn->cached_dir = NULL; +/** Try to guess the number of bytes that will be needed to send the + * spooled objects for <b>conn</b>'s outgoing spool. In the process, + * remove every element of the spool that refers to an absent object, or + * which was published earlier than <b>cutoff</b>. Set *<b>size_out</b> + * to the number of bytes, and *<b>n_expired_out</b> to the number of + * objects removed for being too old. */ +void +dirserv_spool_remove_missing_and_guess_size(dir_connection_t *conn, + time_t cutoff, + int compression, + uint64_t *size_out, + int *n_expired_out) +{ + if (BUG(!conn)) + return; + + smartlist_t *spool = conn->spool; + if (!spool) { + if (size_out) + *size_out = 0; + if (n_expired_out) + *n_expired_out = 0; + return; } - return 0; + int n_expired = 0; + uint64_t total = 0; + SMARTLIST_FOREACH_BEGIN(spool, spooled_resource_t *, spooled) { + time_t published = TIME_MAX; + size_t sz = spooled_resource_estimate_size(spooled, conn, + compression, &published); + if (published < cutoff) { + ++n_expired; + SMARTLIST_DEL_CURRENT(spool, spooled); + spooled_resource_free(spooled); + } else if (sz == 0) { + SMARTLIST_DEL_CURRENT(spool, spooled); + spooled_resource_free(spooled); + } else { + total += sz; + } + } SMARTLIST_FOREACH_END(spooled); + + if (size_out) + *size_out = total; + if (n_expired_out) + *n_expired_out = n_expired; }

-/** Spooling helper: Called when we're spooling networkstatus objects on - * <b>conn</b>, and the outbuf has become too empty. If the current - * networkstatus object (in <b>conn</b>->cached_dir) has more data, pull data - * from there. Otherwise, pop the next fingerprint from fingerprint_stack, - * and start spooling the next networkstatus. (A digest of all 0 bytes is - * treated as a request for the current consensus.) If we run out of entries, - * flushes the zlib state and sets the spool source to NONE. Returns 0 on - * success, negative on failure. */ +/** Helper: used to sort a connection's spool. */ static int -connection_dirserv_add_networkstatus_bytes_to_outbuf(dir_connection_t *conn) -{ - - while (connection_get_outbuf_len(TO_CONN(conn)) < DIRSERV_BUFFER_MIN) { - if (conn->cached_dir) { - int uncompressing = (conn->zlib_state != NULL); - int r = connection_dirserv_add_dir_bytes_to_outbuf(conn); - if (conn->dir_spool_src == DIR_SPOOL_NONE) { - /* add_dir_bytes thinks we're done with the cached_dir. But we - * may have more cached_dirs! */ - conn->dir_spool_src = DIR_SPOOL_NETWORKSTATUS; - /* This bit is tricky. If we were uncompressing the last - * networkstatus, we may need to make a new zlib object to - * uncompress the next one. */ - if (uncompressing && ! conn->zlib_state && - conn->fingerprint_stack && - smartlist_len(conn->fingerprint_stack)) { - conn->zlib_state = tor_zlib_new(0, ZLIB_METHOD, HIGH_COMPRESSION); - } - } - if (r) return r; - } else if (conn->fingerprint_stack && - smartlist_len(conn->fingerprint_stack)) { - /* Add another networkstatus; start serving it. */ - char *fp = smartlist_pop_last(conn->fingerprint_stack); - cached_dir_t *d = lookup_cached_dir_by_fp(fp); - tor_free(fp); - if (d) { - ++d->refcnt; - conn->cached_dir = d; - conn->cached_dir_offset = 0; - } - } else { - connection_dirserv_finish_spooling(conn); - smartlist_free(conn->fingerprint_stack); - conn->fingerprint_stack = NULL; - return 0; +dirserv_spool_sort_comparison_(const void **a_, const void **b_) +{ + const spooled_resource_t *a = *a_; + const spooled_resource_t *b = *b_; + return fast_memcmp(a->digest, b->digest, sizeof(a->digest)); +} + +/** Sort all the entries in <b>conn</b> by digest. */ +void +dirserv_spool_sort(dir_connection_t *conn) +{ + if (conn->spool == NULL) + return; + smartlist_sort(conn->spool, dirserv_spool_sort_comparison_); +} + +/** Return the cache-info for identity fingerprint <b>fp</b>, or + * its extra-info document if <b>extrainfo</b> is true. Return + * NULL if not found or if the descriptor is older than + * <b>publish_cutoff</b>. */ +static const signed_descriptor_t * +get_signed_descriptor_by_fp(const uint8_t *fp, int extrainfo) +{ + if (router_digest_is_me((const char *)fp)) { + if (extrainfo) + return &(router_get_my_extrainfo()->cache_info); + else + return &(router_get_my_routerinfo()->cache_info); + } else { + const routerinfo_t *ri = router_get_by_id_digest((const char *)fp); + if (ri) { + if (extrainfo) + return extrainfo_get_by_descriptor_digest( + ri->cache_info.extra_info_digest); + else + return &ri->cache_info; } } - return 0; + return NULL; }

+/** When we're spooling data onto our outbuf, add more whenever we dip + * below this threshold. */ +#define DIRSERV_BUFFER_MIN 16384 + /** Called whenever we have flushed some directory data in state * SERVER_WRITING. */ int connection_dirserv_flushed_some(dir_connection_t *conn) { tor_assert(conn->base_.state == DIR_CONN_STATE_SERVER_WRITING); - - if (connection_get_outbuf_len(TO_CONN(conn)) >= DIRSERV_BUFFER_MIN) + if (conn->spool == NULL) return 0;

- switch (conn->dir_spool_src) { - case DIR_SPOOL_EXTRA_BY_DIGEST: - case DIR_SPOOL_EXTRA_BY_FP: - case DIR_SPOOL_SERVER_BY_DIGEST: - case DIR_SPOOL_SERVER_BY_FP: - return connection_dirserv_add_servers_to_outbuf(conn); - case DIR_SPOOL_MICRODESC: - return connection_dirserv_add_microdescs_to_outbuf(conn); - case DIR_SPOOL_NETWORKSTATUS: - return connection_dirserv_add_networkstatus_bytes_to_outbuf(conn); - case DIR_SPOOL_NONE: - default: + while (connection_get_outbuf_len(TO_CONN(conn)) < DIRSERV_BUFFER_MIN && + smartlist_len(conn->spool)) { + spooled_resource_t *spooled = + smartlist_get(conn->spool, smartlist_len(conn->spool)-1); + spooled_resource_flush_status_t status; + status = spooled_resource_flush_some(spooled, conn); + if (status == SRFS_ERR) { + return -1; + } else if (status == SRFS_MORE) { return 0; + } + tor_assert(status == SRFS_DONE); + + /* If we're here, we're done flushing this resource. */ + tor_assert(smartlist_pop_last(conn->spool) == spooled); + spooled_resource_free(spooled); + } + + if (smartlist_len(conn->spool) > 0) { + /* We're still spooling something. */ + return 0; + } + + /* If we get here, we're done. */ + smartlist_free(conn->spool); + conn->spool = NULL; + if (conn->zlib_state) { + /* Flush the zlib state: there could be more bytes pending in there, and + * we don't want to omit bytes. */ + connection_write_to_buf_zlib("", 0, conn, 1); + tor_zlib_free(conn->zlib_state); + conn->zlib_state = NULL; } + return 0; +} + +/** Remove every element from <b>conn</b>'s outgoing spool, and delete + * the spool. */ +void +dir_conn_clear_spool(dir_connection_t *conn) +{ + if (!conn || ! conn->spool) + return; + SMARTLIST_FOREACH(conn->spool, spooled_resource_t *, s, + spooled_resource_free(s)); + smartlist_free(conn->spool); + conn->spool = NULL; }

/** Return true iff <b>line</b> is a valid RecommendedPackages line. diff --git a/src/or/dirserv.h b/src/or/dirserv.h index e83da5e..beebe47 100644 --- a/src/or/dirserv.h +++ b/src/or/dirserv.h @@ -32,6 +32,53 @@ /** Maximum allowable length of a version line in a networkstatus. */ #define MAX_V_LINE_LEN 128

+/** Ways to convert a spoolable_resource_t to a bunch of bytes. */ +typedef enum dir_spool_source_t { + DIR_SPOOL_SERVER_BY_DIGEST=1, DIR_SPOOL_SERVER_BY_FP, + DIR_SPOOL_EXTRA_BY_DIGEST, DIR_SPOOL_EXTRA_BY_FP, + DIR_SPOOL_MICRODESC, + DIR_SPOOL_NETWORKSTATUS, +} dir_spool_source_t; +#define dir_spool_source_bitfield_t ENUM_BF(dir_spool_source_t) + +/** Object to remember the identity of an object that we are spooling, + * or about to spool, in response to a directory request. + * + * (Why do we spool? Because some directory responses are very large, + * and we don't want to just shove the complete answer into the output + * buffer: that would take a ridiculous amount of RAM.) + * + * If the spooled resource is relatively small (like microdescriptors, + * descriptors, etc), we look them up by ID as needed, and add the whole + * thing onto the output buffer at once. If the spooled reseource is + * big (like networkstatus documents), we reference-count it, and add it + * a few K at a time. + */ +typedef struct spooled_resource_t { + /** + * If true, we add the entire object to the outbuf. If false, + * we spool the object a few K at a time. + */ + unsigned spool_eagerly : 1; + /** + * Tells us what kind of object to get, and how to look it up. + */ + dir_spool_source_bitfield_t spool_source : 7; + /** + * Tells us the specific object to spool. + */ + uint8_t digest[DIGEST256_LEN]; + /** + * A large object that we're spooling. Holds a reference count. Only + * used when spool_eagerly is false. + */ + struct cached_dir_t *cached_dir_ref; + /** + * The current offset into cached_dir. Only used when spool_eagerly is + * false */ + off_t cached_dir_offset; +} spooled_resource_t; + int connection_dirserv_flushed_some(dir_connection_t *conn);

int dirserv_add_own_fingerprint(crypto_pk_t *pk); @@ -65,10 +112,10 @@ void dirserv_set_cached_consensus_networkstatus(const char *consensus, const common_digests_t *digests, time_t published); void dirserv_clear_old_networkstatuses(time_t cutoff); -int dirserv_get_routerdesc_fingerprints(smartlist_t *fps_out, const char *key, - const char **msg, - int for_unencrypted_conn, - int is_extrainfo); +int dirserv_get_routerdesc_spool(smartlist_t *spools_out, const char *key, + dir_spool_source_t source, + int conn_is_encrytped, + const char **msg_out); int dirserv_get_routerdescs(smartlist_t *descs_out, const char *key, const char **msg); void dirserv_orconn_tls_done(const tor_addr_t *addr, @@ -89,13 +136,6 @@ void dirserv_set_node_flags_from_authoritative_status(node_t *node, uint32_t authstatus);

int dirserv_would_reject_router(const routerstatus_t *rs); -int dirserv_remove_old_statuses(smartlist_t *fps, time_t cutoff); -int dirserv_have_any_serverdesc(smartlist_t *fps, int spool_src); -int dirserv_have_any_microdesc(const smartlist_t *fps); -size_t dirserv_estimate_data_size(smartlist_t *fps, int is_serverdescs, - int compressed); -size_t dirserv_estimate_microdesc_size(const smartlist_t *fps, int compressed); - char *routerstatus_format_entry( const routerstatus_t *rs, const char *version, @@ -141,5 +181,17 @@ int dirserv_read_measured_bandwidths(const char *from_file, int dirserv_read_guardfraction_file(const char *fname, smartlist_t *vote_routerstatuses);

+spooled_resource_t *spooled_resource_new(dir_spool_source_t source, + const uint8_t *digest, + size_t digestlen); +void spooled_resource_free(spooled_resource_t *spooled); +void dirserv_spool_remove_missing_and_guess_size(dir_connection_t *conn, + time_t cutoff, + int compression, + uint64_t *size_out, + int *n_expired_out); +void dirserv_spool_sort(dir_connection_t *conn); +void dir_conn_clear_spool(dir_connection_t *conn); + #endif

diff --git a/src/or/microdesc.c b/src/or/microdesc.c index 140117f..b9b0e83 100644 --- a/src/or/microdesc.c +++ b/src/or/microdesc.c @@ -804,18 +804,6 @@ microdesc_cache_lookup_by_digest256(microdesc_cache_t *cache, const char *d) return md; }

-/** Return the mean size of decriptors added to <b>cache</b> since it was last - * cleared. Used to estimate the size of large downloads. */ -size_t -microdesc_average_size(microdesc_cache_t *cache) -{ - if (!cache) - cache = get_microdesc_cache(); - if (!cache->n_seen) - return 512; - return (size_t)(cache->total_len_seen / cache->n_seen); -} - /** Return a smartlist of all the sha256 digest of the microdescriptors that * are listed in <b>ns</b> but not present in <b>cache</b>. Returns pointers * to internals of <b>ns</b>; you should not free the members of the resulting diff --git a/src/or/microdesc.h b/src/or/microdesc.h index 40c8313..5b1365d 100644 --- a/src/or/microdesc.h +++ b/src/or/microdesc.h @@ -32,8 +32,6 @@ void microdesc_cache_clear(microdesc_cache_t *cache); microdesc_t *microdesc_cache_lookup_by_digest256(microdesc_cache_t *cache, const char *d);

-size_t microdesc_average_size(microdesc_cache_t *cache); - smartlist_t *microdesc_list_missing_digest256(networkstatus_t *ns, microdesc_cache_t *cache, int downloadable_only, diff --git a/src/or/or.h b/src/or/or.h index dee8b85..83a1029 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -1732,14 +1732,6 @@ typedef struct entry_connection_t { unsigned int is_socks_socket:1; } entry_connection_t;

-typedef enum { - DIR_SPOOL_NONE=0, DIR_SPOOL_SERVER_BY_DIGEST, DIR_SPOOL_SERVER_BY_FP, - DIR_SPOOL_EXTRA_BY_DIGEST, DIR_SPOOL_EXTRA_BY_FP, - DIR_SPOOL_NETWORKSTATUS, - DIR_SPOOL_MICRODESC, /* NOTE: if we add another entry, add another bit. */ -} dir_spool_source_t; -#define dir_spool_source_bitfield_t ENUM_BF(dir_spool_source_t) - /** Subtype of connection_t for an "directory connection" -- that is, an HTTP * connection to retrieve or serve directory material. */ typedef struct dir_connection_t { @@ -1754,21 +1746,13 @@ typedef struct dir_connection_t { char *requested_resource; unsigned int dirconn_direct:1; /**< Is this dirconn direct, or via Tor? */

- /* Used only for server sides of some dir connections, to implement - * "spooling" of directory material to the outbuf. Otherwise, we'd have - * to append everything to the outbuf in one enormous chunk. */ - /** What exactly are we spooling right now? */ - dir_spool_source_bitfield_t dir_spool_src : 3; - /** If we're fetching descriptors, what router purpose shall we assign * to them? */ uint8_t router_purpose; - /** List of fingerprints for networkstatuses or descriptors to be spooled. */ - smartlist_t *fingerprint_stack; - /** A cached_dir_t object that we're currently spooling out */ - struct cached_dir_t *cached_dir; - /** The current offset into cached_dir. */ - off_t cached_dir_offset; + + /** List of spooled_resource_t for objects that we're spooling. We use + * it from back to front. */ + smartlist_t *spool; /** The zlib object doing on-the-fly compression for spooled data. */ tor_zlib_state_t *zlib_state;

diff --git a/src/test/test_dir_handle_get.c b/src/test/test_dir_handle_get.c index a0868f9..02ee6ad 100644 --- a/src/test/test_dir_handle_get.c +++ b/src/test/test_dir_handle_get.c @@ -743,7 +743,7 @@ test_dir_handle_get_server_descriptors_not_found(void* data) NULL, NULL, 1, 0);

tt_str_op(NOT_FOUND, OP_EQ, header); - tt_int_op(conn->dir_spool_src, OP_EQ, DIR_SPOOL_SERVER_BY_FP); + tt_ptr_op(conn->spool, OP_EQ, NULL);

done: UNMOCK(connection_write_to_buf_impl_); @@ -773,6 +773,7 @@ test_dir_handle_get_server_descriptors_all(void* data) tt_int_op(smartlist_len(our_routerlist->routers), OP_GE, 1); mock_routerinfo = smartlist_get(our_routerlist->routers, 0); set_server_identity_key(mock_routerinfo->identity_pkey); + mock_routerinfo->cache_info.published_on = time(NULL);

/* Treat "all" requests as if they were unencrypted */ mock_routerinfo->cache_info.send_unencrypted = 1; @@ -787,7 +788,7 @@ test_dir_handle_get_server_descriptors_all(void* data) //which is smaller than that by annotation_len bytes fetch_from_buf_http(TO_CONN(conn)->outbuf, &header, MAX_HEADERS_SIZE, &body, &body_used, - mock_routerinfo->cache_info.signed_descriptor_len+1, 0); + 1024*1024, 0);

tt_assert(header); tt_assert(body); @@ -803,7 +804,7 @@ test_dir_handle_get_server_descriptors_all(void* data)

tt_str_op(body, OP_EQ, mock_routerinfo->cache_info.signed_descriptor_body + mock_routerinfo->cache_info.annotations_len); - tt_int_op(conn->dir_spool_src, OP_EQ, DIR_SPOOL_NONE); + tt_ptr_op(conn->spool, OP_EQ, NULL);

done: NS_UNMOCK(router_get_my_routerinfo); @@ -882,6 +883,7 @@ test_dir_handle_get_server_descriptors_authority(void* data) mock_routerinfo->cache_info.signed_descriptor_len = strlen(TEST_DESCRIPTOR) - annotation_len;; mock_routerinfo->cache_info.annotations_len = annotation_len; + mock_routerinfo->cache_info.published_on = time(NULL);

conn = new_dir_conn();

@@ -904,7 +906,7 @@ test_dir_handle_get_server_descriptors_authority(void* data) tt_int_op(body_used, OP_EQ, strlen(body));

tt_str_op(body, OP_EQ, TEST_DESCRIPTOR + annotation_len); - tt_int_op(conn->dir_spool_src, OP_EQ, DIR_SPOOL_NONE); + tt_ptr_op(conn->spool, OP_EQ, NULL);

done: NS_UNMOCK(router_get_my_routerinfo); @@ -946,6 +948,7 @@ test_dir_handle_get_server_descriptors_fp(void* data) mock_routerinfo->cache_info.signed_descriptor_len = strlen(TEST_DESCRIPTOR) - annotation_len; mock_routerinfo->cache_info.annotations_len = annotation_len; + mock_routerinfo->cache_info.published_on = time(NULL);

conn = new_dir_conn();

@@ -975,7 +978,7 @@ test_dir_handle_get_server_descriptors_fp(void* data) tt_int_op(body_used, OP_EQ, strlen(body));

tt_str_op(body, OP_EQ, TEST_DESCRIPTOR + annotation_len); - tt_int_op(conn->dir_spool_src, OP_EQ, DIR_SPOOL_NONE); + tt_ptr_op(conn->spool, OP_EQ, NULL);

done: NS_UNMOCK(router_get_my_routerinfo); @@ -1041,7 +1044,7 @@ test_dir_handle_get_server_descriptors_d(void* data)

tt_str_op(body, OP_EQ, router->cache_info.signed_descriptor_body + router->cache_info.annotations_len); - tt_int_op(conn->dir_spool_src, OP_EQ, DIR_SPOOL_NONE); + tt_ptr_op(conn->spool, OP_EQ, NULL);

done: UNMOCK(connection_write_to_buf_impl_); @@ -1096,7 +1099,7 @@ test_dir_handle_get_server_descriptors_busy(void* data) tt_assert(header); tt_str_op(SERVER_BUSY, OP_EQ, header);

- tt_int_op(conn->dir_spool_src, OP_EQ, DIR_SPOOL_NONE); + tt_ptr_op(conn->spool, OP_EQ, NULL);

done: UNMOCK(get_options);