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Add a "Consensus diff manager" module.
This module's job is to remember old consensus documents, to calculate their diffs on demand, and to . There are some incomplete points in this code; I've marked them with "XXXX". I intend to fix them in separate commits, since I believe doing it in separate commits will make the branch easier to review.
This commit is contained in:
Nick Mathewson
parent
b022ea32a6
commit
bc91808c47
719
src/or/consdiffmgr.c
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719
src/or/consdiffmgr.c
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/* Copyright (c) 2017, The Tor Project, Inc. */
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/* See LICENSE for licensing information */
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/**
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* \file consdiffmsr.c
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*
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* \brief consensus diff manager functions
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*
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* This module is run by directory authorities and caches in order
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* to remember a number of past consensus documents, and to generate
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* and serve the diffs from those documents to the latest consensus.
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*/
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#include "or.h"
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#include "conscache.h"
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#include "consdiff.h"
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#include "consdiffmgr.h"
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#include "cpuworker.h"
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#include "networkstatus.h"
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#include "workqueue.h"
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/* XXXX support compression */
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/**
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* Labels to apply to items in the conscache object.
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*
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* @{
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*/
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/* One of DOCTYPE_CONSENSUS or DOCTYPE_CONSENSUS_DIFF */
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#define LABEL_DOCTYPE "document-type"
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/* The valid-after time for a consensus (or for the target consensus of a
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* diff), encoded as ISO UTC. */
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#define LABEL_VALID_AFTER "consensus-valid-after"
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/* A hex encoded SHA3 digest of the object after decompression. */
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#define LABEL_SHA3_DIGEST "sha3-digest"
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/* The flavor of the consensus or consensuses diff */
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#define LABEL_FLAVOR "consensus-flavor"
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/* Diff only: the SHA3 digest of the source consensus. */
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#define LABEL_FROM_SHA3_DIGEST "from-sha3-digest"
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/* Diff only: the SHA3 digest of the target consensus. */
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#define LABEL_TARGET_SHA3_DIGEST "target-sha3-digest"
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/* Diff only: the valid-after date of the source consensus. */
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#define LABEL_FROM_VALID_AFTER "from-valid-after"
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/** @} */
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#define DOCTYPE_CONSENSUS "consensus"
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#define DOCTYPE_CONSENSUS_DIFF "consensus-diff"
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/**
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* Underlying directory that stores consensuses and consensus diffs. Don't
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* use this directly: use cdm_cache_get() instead.
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*/
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static consensus_cache_t *cons_diff_cache = NULL;
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/**
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* If true, we have learned at least one new consensus since the
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* consensus cache was last up-to-date.
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*/
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static int cdm_cache_dirty = 0;
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/**
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* Configuration for this module
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*/
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static consdiff_cfg_t consdiff_cfg = {
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/* .cache_max_age_hours = */ 24 * 90,
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/* .cache_max_num = */ 1440
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};
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static int consensus_diff_queue_diff_work(consensus_cache_entry_t *diff_from,
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consensus_cache_entry_t *diff_to);
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/**
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* Helper: initialize <b>cons_diff_cache</b>.
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*/
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static void
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cdm_cache_init(void)
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{
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unsigned n_entries = consdiff_cfg.cache_max_num * 2;
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tor_assert(cons_diff_cache == NULL);
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cons_diff_cache = consensus_cache_open("diff-cache", n_entries);
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if (cons_diff_cache == NULL) {
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log_err(LD_FS, "Error: Couldn't open storage for consensus diffs.");
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tor_assert_unreached();
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}
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cdm_cache_dirty = 1;
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}
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/**
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* Helper: return the consensus_cache_t * that backs this manager,
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* initializing it if needed.
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*/
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static consensus_cache_t *
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cdm_cache_get(void)
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{
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if (PREDICT_UNLIKELY(cons_diff_cache == NULL)) {
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cdm_cache_init();
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}
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return cons_diff_cache;
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}
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/**
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* Helper: given a list of labels, prepend the hex-encoded SHA3 digest
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* of the <b>bodylen</b>-byte object at <b>body</b> to those labels,
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* with LABEL_SHA3_DIGEST as its label.
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*/
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static void
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cdm_labels_prepend_sha3(config_line_t **labels,
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const uint8_t *body,
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size_t bodylen)
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{
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uint8_t sha3_digest[DIGEST256_LEN];
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char hexdigest[HEX_DIGEST256_LEN+1];
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crypto_digest256((char *)sha3_digest,
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(const char *)body, bodylen, DIGEST_SHA3_256);
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base16_encode(hexdigest, sizeof(hexdigest),
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(const char *)sha3_digest, sizeof(sha3_digest));
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config_line_prepend(labels, LABEL_SHA3_DIGEST, hexdigest);
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}
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/**
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* Helper: look for a consensus with the given <b>flavor</b> and
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* <b>valid_after</b> time in the cache. Return that consensus if it's
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* present, or NULL if it's missing.
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*/
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static consensus_cache_entry_t *
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cdm_cache_lookup_consensus(consensus_flavor_t flavor, time_t valid_after)
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{
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char formatted_time[ISO_TIME_LEN+1];
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format_iso_time_nospace(formatted_time, valid_after);
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const char *flavname = networkstatus_get_flavor_name(flavor);
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/* We'll filter by valid-after time first, since that should
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* match the fewest documents. */
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// XXXX This is stupid and it should be a hash table.
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smartlist_t *matches = smartlist_new();
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consensus_cache_find_all(matches, cdm_cache_get(),
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LABEL_VALID_AFTER, formatted_time);
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consensus_cache_filter_list(matches, LABEL_FLAVOR, flavname);
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consensus_cache_filter_list(matches, LABEL_DOCTYPE, DOCTYPE_CONSENSUS);
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consensus_cache_entry_t *result = NULL;
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if (smartlist_len(matches) > 1) {
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log_warn(LD_BUG, "How odd; there appear to be two matching consensuses "
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"with flavor %s published at %s.",
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flavname, formatted_time);
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}
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if (smartlist_len(matches)) {
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result = smartlist_get(matches, 0);
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}
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smartlist_free(matches);
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return result;
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}
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/**
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* Given a string containing a networkstatus consensus, and the results of
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* having parsed that consensus, add that consensus to the cache if it is not
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* already present and not too old. Create new consensus diffs from or to
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* that consensus as appropriate.
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*
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* Return 0 on success and -1 on failure.
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*/
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int
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consdiffmgr_add_consensus(const char *consensus,
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const networkstatus_t *as_parsed)
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{
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if (BUG(consensus == NULL) || BUG(as_parsed == NULL))
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return -1; // LCOV_EXCL_LINE
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if (BUG(as_parsed->type != NS_TYPE_CONSENSUS))
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return -1; // LCOV_EXCL_LINE
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const consensus_flavor_t flavor = as_parsed->flavor;
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const time_t valid_after = as_parsed->valid_after;
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if (valid_after < approx_time() - 3600 * consdiff_cfg.cache_max_age_hours) {
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log_info(LD_DIRSERV, "We don't care about this consensus document; it's "
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"too old.");
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return -1;
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}
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/* Do we already have this one? */
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consensus_cache_entry_t *entry =
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cdm_cache_lookup_consensus(flavor, valid_after);
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if (entry) {
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log_info(LD_DIRSERV, "We already have a copy of that consensus");
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return -1;
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}
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/* We don't have it. Add it to the cache. */
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{
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size_t bodylen = strlen(consensus);
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config_line_t *labels = NULL;
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char formatted_time[ISO_TIME_LEN+1];
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format_iso_time_nospace(formatted_time, valid_after);
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const char *flavname = networkstatus_get_flavor_name(flavor);
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cdm_labels_prepend_sha3(&labels, (const uint8_t *)consensus, bodylen);
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config_line_prepend(&labels, LABEL_FLAVOR, flavname);
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config_line_prepend(&labels, LABEL_VALID_AFTER, formatted_time);
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config_line_prepend(&labels, LABEL_DOCTYPE, DOCTYPE_CONSENSUS);
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entry = consensus_cache_add(cdm_cache_get(),
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labels,
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(const uint8_t *)consensus,
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bodylen);
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config_free_lines(labels);
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}
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if (entry)
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consensus_cache_entry_decref(entry);
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cdm_cache_dirty = 1;
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return entry ? 0 : -1;
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}
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/**
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* Helper: used to sort two smartlists of consensus_cache_entry_t by their
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* LABEL_VALID_AFTER labels.
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*/
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static int
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compare_by_valid_after_(const void **a, const void **b)
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{
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const consensus_cache_entry_t *e1 = *a;
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const consensus_cache_entry_t *e2 = *b;
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/* We're in luck here: sorting UTC iso-encoded values lexically will work
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* fine (until 9999). */
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return strcmp_opt(consensus_cache_entry_get_value(e1, LABEL_VALID_AFTER),
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consensus_cache_entry_get_value(e2, LABEL_VALID_AFTER));
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}
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/**
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* Helper: Sort <b>lst</b> by LABEL_VALID_AFTER and return the most recent
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* entry.
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*/
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static consensus_cache_entry_t *
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sort_and_find_most_recent(smartlist_t *lst)
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{
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smartlist_sort(lst, compare_by_valid_after_);
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if (smartlist_len(lst)) {
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return smartlist_get(lst, smartlist_len(lst) - 1);
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} else {
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return NULL;
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}
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}
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/**
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* Look up consensus_cache_entry_t for the consensus of type <b>flavor</b>,
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* from the source consensus with the specified digest (which must be SHA3).
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*
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* If the diff is present, store it into *<b>entry_out</b> and return
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* CONSDIFF_AVAILABLE. Otherwise return CONSDIFF_NOT_FOUND or
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* CONSDIFF_IN_PROGRESS.
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*/
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consdiff_status_t
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consdiffmgr_find_diff_from(consensus_cache_entry_t **entry_out,
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consensus_flavor_t flavor,
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int digest_type,
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const uint8_t *digest,
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size_t digestlen)
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{
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// XXXX actually return IN_PROGRESS some times?
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if (BUG(digest_type != DIGEST_SHA3_256) ||
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BUG(digestlen != DIGEST256_LEN)) {
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return CONSDIFF_NOT_FOUND; // LCOV_EXCL_LINE
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}
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char hex[HEX_DIGEST256_LEN+1];
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base16_encode(hex, sizeof(hex), (const char *)digest, digestlen);
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const char *flavname = networkstatus_get_flavor_name(flavor);
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smartlist_t *matches = smartlist_new();
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consensus_cache_find_all(matches, cdm_cache_get(),
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LABEL_FROM_SHA3_DIGEST, hex);
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consensus_cache_filter_list(matches, LABEL_FLAVOR, flavname);
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consensus_cache_filter_list(matches, LABEL_DOCTYPE, DOCTYPE_CONSENSUS_DIFF);
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*entry_out = sort_and_find_most_recent(matches);
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consdiff_status_t result =
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(*entry_out) ? CONSDIFF_AVAILABLE : CONSDIFF_NOT_FOUND;
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smartlist_free(matches);
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return result;
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}
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/**
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* Perform periodic cleanup tasks on the consensus diff cache. Return
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* the number of objects marked for deletion.
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*/
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int
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consdiffmgr_cleanup(void)
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{
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smartlist_t *objects = smartlist_new();
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smartlist_t *consensuses = smartlist_new();
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smartlist_t *diffs = smartlist_new();
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int n_to_delete = 0;
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log_debug(LD_DIRSERV, "Looking for consdiffmgr entries to remove");
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// 1. Delete any consensus or diff or anything whose valid_after is too old.
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const time_t valid_after_cutoff =
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approx_time() - 3600 * consdiff_cfg.cache_max_age_hours;
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consensus_cache_find_all(objects, cdm_cache_get(),
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NULL, NULL);
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SMARTLIST_FOREACH_BEGIN(objects, consensus_cache_entry_t *, ent) {
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const char *lv_valid_after =
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consensus_cache_entry_get_value(ent, LABEL_VALID_AFTER);
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if (! lv_valid_after) {
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log_debug(LD_DIRSERV, "Ignoring entry because it had no %s label",
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LABEL_VALID_AFTER);
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continue;
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}
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time_t valid_after = 0;
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if (parse_iso_time_nospace(lv_valid_after, &valid_after) < 0) {
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log_debug(LD_DIRSERV, "Ignoring entry because its %s value (%s) was "
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"unparseable", LABEL_VALID_AFTER, escaped(lv_valid_after));
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continue;
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}
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if (valid_after < valid_after_cutoff) {
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log_debug(LD_DIRSERV, "Deleting entry because its %s value (%s) was "
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"too old", LABEL_VALID_AFTER, lv_valid_after);
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consensus_cache_entry_mark_for_removal(ent);
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++n_to_delete;
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}
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} SMARTLIST_FOREACH_END(ent);
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// 2. Delete all diffs that lead to a consensus whose valid-after is not the
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// latest.
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for (int flav = 0; flav < N_CONSENSUS_FLAVORS; ++flav) {
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const char *flavname = networkstatus_get_flavor_name(flav);
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/* Determine the most recent consensus of this flavor */
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consensus_cache_find_all(consensuses, cdm_cache_get(),
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LABEL_DOCTYPE, DOCTYPE_CONSENSUS);
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consensus_cache_filter_list(consensuses, LABEL_FLAVOR, flavname);
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consensus_cache_entry_t *most_recent =
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sort_and_find_most_recent(consensuses);
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if (most_recent == NULL)
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continue;
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const char *most_recent_sha3 =
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consensus_cache_entry_get_value(most_recent, LABEL_SHA3_DIGEST);
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if (BUG(most_recent_sha3 == NULL))
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continue; // LCOV_EXCL_LINE
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/* consider all such-flavored diffs, and look to see if they match. */
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consensus_cache_find_all(diffs, cdm_cache_get(),
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LABEL_DOCTYPE, DOCTYPE_CONSENSUS_DIFF);
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consensus_cache_filter_list(diffs, LABEL_FLAVOR, flavname);
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SMARTLIST_FOREACH_BEGIN(diffs, consensus_cache_entry_t *, diff) {
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const char *this_diff_target_sha3 =
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consensus_cache_entry_get_value(diff, LABEL_TARGET_SHA3_DIGEST);
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if (!this_diff_target_sha3)
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continue;
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||||||
|
if (strcmp(this_diff_target_sha3, most_recent_sha3)) {
|
||||||
|
consensus_cache_entry_mark_for_removal(diff);
|
||||||
|
++n_to_delete;
|
||||||
|
}
|
||||||
|
} SMARTLIST_FOREACH_END(diff);
|
||||||
|
smartlist_clear(consensuses);
|
||||||
|
smartlist_clear(diffs);
|
||||||
|
}
|
||||||
|
|
||||||
|
smartlist_free(objects);
|
||||||
|
smartlist_free(consensuses);
|
||||||
|
smartlist_free(diffs);
|
||||||
|
// XXXX for anything where the sha3 doesn't match -- delete it. But not
|
||||||
|
// XXXX here. Somewhere else?
|
||||||
|
|
||||||
|
// Actually remove files, if they're not used.
|
||||||
|
consensus_cache_delete_pending(cdm_cache_get());
|
||||||
|
return n_to_delete;
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Initialize the consensus diff manager and its cache, and configure
|
||||||
|
* its parameters based on the latest torrc and networkstatus parameters.
|
||||||
|
*/
|
||||||
|
void
|
||||||
|
consdiffmgr_configure(const consdiff_cfg_t *cfg)
|
||||||
|
{
|
||||||
|
memcpy(&consdiff_cfg, cfg, sizeof(consdiff_cfg));
|
||||||
|
|
||||||
|
(void) cdm_cache_get();
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Helper: build new diffs of <b>flavor</b> as needed
|
||||||
|
*/
|
||||||
|
static void
|
||||||
|
consdiffmgr_rescan_flavor_(consensus_flavor_t flavor)
|
||||||
|
{
|
||||||
|
smartlist_t *matches = NULL;
|
||||||
|
smartlist_t *diffs = NULL;
|
||||||
|
smartlist_t *compute_diffs_from = NULL;
|
||||||
|
strmap_t *have_diff_from = NULL;
|
||||||
|
|
||||||
|
// look for the most recent consensus, and for all previous in-range
|
||||||
|
// consensuses. Do they all have diffs to it?
|
||||||
|
const char *flavname = networkstatus_get_flavor_name(flavor);
|
||||||
|
|
||||||
|
// 1. find the most recent consensus, and the ones that we might want
|
||||||
|
// to diff to it.
|
||||||
|
matches = smartlist_new();
|
||||||
|
consensus_cache_find_all(matches, cdm_cache_get(),
|
||||||
|
LABEL_FLAVOR, flavname);
|
||||||
|
consensus_cache_filter_list(matches, LABEL_DOCTYPE, DOCTYPE_CONSENSUS);
|
||||||
|
consensus_cache_entry_t *most_recent = sort_and_find_most_recent(matches);
|
||||||
|
if (!most_recent) {
|
||||||
|
log_info(LD_DIRSERV, "No 'most recent' %s consensus found; "
|
||||||
|
"not making diffs", flavname);
|
||||||
|
goto done;
|
||||||
|
}
|
||||||
|
tor_assert(smartlist_len(matches));
|
||||||
|
smartlist_del(matches, smartlist_len(matches) - 1);
|
||||||
|
|
||||||
|
const char *most_recent_valid_after =
|
||||||
|
consensus_cache_entry_get_value(most_recent, LABEL_VALID_AFTER);
|
||||||
|
if (BUG(most_recent_valid_after == NULL))
|
||||||
|
goto done; //LCOV_EXCL_LINE
|
||||||
|
|
||||||
|
// 2. Find all the relevant diffs _to_ this consensus. These are ones
|
||||||
|
// that we don't need to compute.
|
||||||
|
diffs = smartlist_new();
|
||||||
|
consensus_cache_find_all(diffs, cdm_cache_get(),
|
||||||
|
LABEL_VALID_AFTER, most_recent_valid_after);
|
||||||
|
consensus_cache_filter_list(diffs, LABEL_DOCTYPE, DOCTYPE_CONSENSUS_DIFF);
|
||||||
|
consensus_cache_filter_list(diffs, LABEL_FLAVOR, flavname);
|
||||||
|
have_diff_from = strmap_new();
|
||||||
|
SMARTLIST_FOREACH_BEGIN(diffs, consensus_cache_entry_t *, diff) {
|
||||||
|
const char *va = consensus_cache_entry_get_value(diff,
|
||||||
|
LABEL_FROM_VALID_AFTER);
|
||||||
|
if (BUG(va == NULL))
|
||||||
|
continue; // LCOV_EXCL_LINE
|
||||||
|
strmap_set(have_diff_from, va, diff);
|
||||||
|
} SMARTLIST_FOREACH_END(diff);
|
||||||
|
|
||||||
|
// 3. See which consensuses in 'matches' don't have diffs yet.
|
||||||
|
smartlist_reverse(matches); // from newest to oldest.
|
||||||
|
compute_diffs_from = smartlist_new();
|
||||||
|
SMARTLIST_FOREACH_BEGIN(matches, consensus_cache_entry_t *, ent) {
|
||||||
|
const char *va = consensus_cache_entry_get_value(ent, LABEL_VALID_AFTER);
|
||||||
|
if (BUG(va == NULL))
|
||||||
|
continue; // LCOV_EXCL_LINE
|
||||||
|
if (strmap_get(have_diff_from, va) != NULL)
|
||||||
|
continue; /* we already have this one. */
|
||||||
|
smartlist_add(compute_diffs_from, ent);
|
||||||
|
} SMARTLIST_FOREACH_END(ent);
|
||||||
|
|
||||||
|
log_info(LD_DIRSERV,
|
||||||
|
"The most recent %s consensus is valid-after %s. We have diffs to "
|
||||||
|
"this consensus for %d/%d older %s consensuses. Generating diffs "
|
||||||
|
"for the other %d.",
|
||||||
|
flavname,
|
||||||
|
most_recent_valid_after,
|
||||||
|
smartlist_len(matches) - smartlist_len(compute_diffs_from),
|
||||||
|
smartlist_len(matches),
|
||||||
|
flavname,
|
||||||
|
smartlist_len(compute_diffs_from));
|
||||||
|
|
||||||
|
// 4. Actually launch the requests.
|
||||||
|
SMARTLIST_FOREACH_BEGIN(compute_diffs_from, consensus_cache_entry_t *, c) {
|
||||||
|
if (BUG(c == most_recent))
|
||||||
|
continue; // LCOV_EXCL_LINE
|
||||||
|
|
||||||
|
// XXXX how do we know that we are not already computing this?????
|
||||||
|
// XXXX DO NOT MERGE UNTIL THAT ISSUE IS SOLVED.
|
||||||
|
consensus_diff_queue_diff_work(c, most_recent);
|
||||||
|
} SMARTLIST_FOREACH_END(c);
|
||||||
|
|
||||||
|
done:
|
||||||
|
smartlist_free(matches);
|
||||||
|
smartlist_free(diffs);
|
||||||
|
smartlist_free(compute_diffs_from);
|
||||||
|
strmap_free(have_diff_from, NULL);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Build new diffs as needed.
|
||||||
|
*/
|
||||||
|
void
|
||||||
|
consdiffmgr_rescan(void)
|
||||||
|
{
|
||||||
|
if (cdm_cache_dirty == 0)
|
||||||
|
return;
|
||||||
|
|
||||||
|
// Clean up here to make room for new diffs, and to ensure that older
|
||||||
|
// consensuses do not have any entries.
|
||||||
|
consdiffmgr_cleanup();
|
||||||
|
|
||||||
|
for (int flav = 0; flav < N_CONSENSUS_FLAVORS; ++flav) {
|
||||||
|
consdiffmgr_rescan_flavor_((consensus_flavor_t) flav);
|
||||||
|
}
|
||||||
|
|
||||||
|
cdm_cache_dirty = 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Called before shutdown: drop all storage held by the consdiffmgr.c module.
|
||||||
|
*/
|
||||||
|
void
|
||||||
|
consdiffmgr_free_all(void)
|
||||||
|
{
|
||||||
|
consensus_cache_free(cons_diff_cache);
|
||||||
|
cons_diff_cache = NULL;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* =====
|
||||||
|
Thread workers
|
||||||
|
=====*/
|
||||||
|
|
||||||
|
/**
|
||||||
|
* An object passed to a worker thread that will try to produce a consensus
|
||||||
|
* diff.
|
||||||
|
*/
|
||||||
|
typedef struct consensus_diff_worker_job_t {
|
||||||
|
/**
|
||||||
|
* Input: The consensus to compute the diff from. Holds a reference to the
|
||||||
|
* cache entry, which must not be released until the job is passed back to
|
||||||
|
* the main thread. The body must be mapped into memory in the main thread.
|
||||||
|
*/
|
||||||
|
consensus_cache_entry_t *diff_from;
|
||||||
|
/**
|
||||||
|
* Input: The consensus to compute the diff to. Holds a reference to the
|
||||||
|
* cache entry, which must not be released until the job is passed back to
|
||||||
|
* the main thread. The body must be mapped into memory in the main thread.
|
||||||
|
*/
|
||||||
|
consensus_cache_entry_t *diff_to;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Output: Labels to store in the cache associated with this diff.
|
||||||
|
*/
|
||||||
|
config_line_t *labels_out;
|
||||||
|
/**
|
||||||
|
* Output: Body of the diff
|
||||||
|
*/
|
||||||
|
uint8_t *body_out;
|
||||||
|
/**
|
||||||
|
* Output: length of body_out
|
||||||
|
*/
|
||||||
|
size_t bodylen_out;
|
||||||
|
} consensus_diff_worker_job_t;
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Worker function. This function runs inside a worker thread and receives
|
||||||
|
* a consensus_diff_worker_job_t as its input.
|
||||||
|
*/
|
||||||
|
static workqueue_reply_t
|
||||||
|
consensus_diff_worker_threadfn(void *state_, void *work_)
|
||||||
|
{
|
||||||
|
(void)state_;
|
||||||
|
consensus_diff_worker_job_t *job = work_;
|
||||||
|
const uint8_t *diff_from, *diff_to;
|
||||||
|
size_t len_from, len_to;
|
||||||
|
int r;
|
||||||
|
/* We need to have the body already mapped into RAM here.
|
||||||
|
*/
|
||||||
|
r = consensus_cache_entry_get_body(job->diff_from, &diff_from, &len_from);
|
||||||
|
if (BUG(r < 0))
|
||||||
|
return WQ_RPL_REPLY; // LCOV_EXCL_LINE
|
||||||
|
r = consensus_cache_entry_get_body(job->diff_to, &diff_to, &len_to);
|
||||||
|
if (BUG(r < 0))
|
||||||
|
return WQ_RPL_REPLY; // LCOV_EXCL_LINE
|
||||||
|
|
||||||
|
const char *lv_to_valid_after =
|
||||||
|
consensus_cache_entry_get_value(job->diff_to, LABEL_VALID_AFTER);
|
||||||
|
const char *lv_from_valid_after =
|
||||||
|
consensus_cache_entry_get_value(job->diff_from, LABEL_VALID_AFTER);
|
||||||
|
const char *lv_from_digest =
|
||||||
|
consensus_cache_entry_get_value(job->diff_from, LABEL_SHA3_DIGEST);
|
||||||
|
const char *lv_from_flavor =
|
||||||
|
consensus_cache_entry_get_value(job->diff_from, LABEL_FLAVOR);
|
||||||
|
const char *lv_to_flavor =
|
||||||
|
consensus_cache_entry_get_value(job->diff_to, LABEL_FLAVOR);
|
||||||
|
const char *lv_to_digest =
|
||||||
|
consensus_cache_entry_get_value(job->diff_to, LABEL_SHA3_DIGEST);
|
||||||
|
|
||||||
|
/* All these values are mandatory on the input */
|
||||||
|
if (BUG(!lv_to_valid_after) ||
|
||||||
|
BUG(!lv_from_valid_after) ||
|
||||||
|
BUG(!lv_from_digest) ||
|
||||||
|
BUG(!lv_from_flavor) ||
|
||||||
|
BUG(!lv_to_flavor)) {
|
||||||
|
return WQ_RPL_REPLY; // LCOV_EXCL_LINE
|
||||||
|
}
|
||||||
|
/* The flavors need to match */
|
||||||
|
if (BUG(strcmp(lv_from_flavor, lv_to_flavor))) {
|
||||||
|
return WQ_RPL_REPLY; // LCOV_EXCL_LINE
|
||||||
|
}
|
||||||
|
|
||||||
|
char *consensus_diff;
|
||||||
|
{
|
||||||
|
// XXXX the input might not be nul-terminated. And also we wanted to
|
||||||
|
// XXXX support compression later I guess. So, we need to copy here.
|
||||||
|
char *diff_from_nt, *diff_to_nt;
|
||||||
|
diff_from_nt = tor_memdup_nulterm(diff_from, len_from);
|
||||||
|
diff_to_nt = tor_memdup_nulterm(diff_to, len_to);
|
||||||
|
|
||||||
|
// XXXX ugh; this is going to calculate the SHA3 of both its
|
||||||
|
// XXXX inputs again, even though we already have that. Maybe it's time
|
||||||
|
// XXXX to change the API here?
|
||||||
|
consensus_diff = consensus_diff_generate(diff_from_nt, diff_to_nt);
|
||||||
|
tor_free(diff_from_nt);
|
||||||
|
tor_free(diff_to_nt);
|
||||||
|
}
|
||||||
|
if (!consensus_diff) {
|
||||||
|
/* Couldn't generate consensus; we'll leave the reply blank. */
|
||||||
|
return WQ_RPL_REPLY;
|
||||||
|
}
|
||||||
|
|
||||||
|
/* Send the reply */
|
||||||
|
job->body_out = (uint8_t *) consensus_diff;
|
||||||
|
job->bodylen_out = strlen(consensus_diff);
|
||||||
|
|
||||||
|
cdm_labels_prepend_sha3(&job->labels_out, job->body_out, job->bodylen_out);
|
||||||
|
config_line_prepend(&job->labels_out, LABEL_FROM_VALID_AFTER,
|
||||||
|
lv_from_valid_after);
|
||||||
|
config_line_prepend(&job->labels_out, LABEL_VALID_AFTER, lv_to_valid_after);
|
||||||
|
config_line_prepend(&job->labels_out, LABEL_FLAVOR, lv_from_flavor);
|
||||||
|
config_line_prepend(&job->labels_out, LABEL_FROM_SHA3_DIGEST,
|
||||||
|
lv_from_digest);
|
||||||
|
config_line_prepend(&job->labels_out, LABEL_TARGET_SHA3_DIGEST,
|
||||||
|
lv_to_digest);
|
||||||
|
config_line_prepend(&job->labels_out, LABEL_DOCTYPE, DOCTYPE_CONSENSUS_DIFF);
|
||||||
|
return WQ_RPL_REPLY;
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Helper: release all storage held in <b>job</b>.
|
||||||
|
*/
|
||||||
|
static void
|
||||||
|
consensus_diff_worker_job_free(consensus_diff_worker_job_t *job)
|
||||||
|
{
|
||||||
|
if (!job)
|
||||||
|
return;
|
||||||
|
tor_free(job->body_out);
|
||||||
|
config_free_lines(job->labels_out);
|
||||||
|
consensus_cache_entry_decref(job->diff_from);
|
||||||
|
consensus_cache_entry_decref(job->diff_to);
|
||||||
|
tor_free(job);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Worker function: This function runs in the main thread, and receives
|
||||||
|
* a consensus_diff_worker_job_t that the worker thread has already
|
||||||
|
* processed.
|
||||||
|
*/
|
||||||
|
static void
|
||||||
|
consensus_diff_worker_replyfn(void *work_)
|
||||||
|
{
|
||||||
|
tor_assert(in_main_thread());
|
||||||
|
tor_assert(work_);
|
||||||
|
|
||||||
|
consensus_diff_worker_job_t *job = work_;
|
||||||
|
|
||||||
|
const char *lv_from_digest =
|
||||||
|
consensus_cache_entry_get_value(job->diff_from, LABEL_SHA3_DIGEST);
|
||||||
|
const char *lv_to_digest =
|
||||||
|
consensus_cache_entry_get_value(job->diff_to, LABEL_SHA3_DIGEST);
|
||||||
|
if (BUG(lv_from_digest == NULL))
|
||||||
|
lv_from_digest = "???"; // LCOV_EXCL_LINE
|
||||||
|
if (BUG(lv_to_digest == NULL))
|
||||||
|
lv_to_digest = "???"; // LCOV_EXCL_LINE
|
||||||
|
|
||||||
|
if (job->body_out && job->bodylen_out && job->labels_out) {
|
||||||
|
/* Success! Store the results */
|
||||||
|
log_info(LD_DIRSERV, "Adding consensus diff from %s to %s",
|
||||||
|
lv_from_digest, lv_to_digest);
|
||||||
|
consensus_cache_add(cdm_cache_get(), job->labels_out,
|
||||||
|
job->body_out,
|
||||||
|
job->bodylen_out);
|
||||||
|
} else {
|
||||||
|
/* Failure! Nothing to do but complain */
|
||||||
|
log_warn(LD_DIRSERV,
|
||||||
|
"Worker was unable to compute consensus diff "
|
||||||
|
"from %s to %s", lv_from_digest, lv_to_digest);
|
||||||
|
/* XXXX Actually, we should cache this failure and not repeat the
|
||||||
|
* attempt over and over */
|
||||||
|
}
|
||||||
|
|
||||||
|
consensus_diff_worker_job_free(job);
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Queue the job of computing the diff from <b>diff_from</b> to <b>diff_to</b>
|
||||||
|
* in a worker thread.
|
||||||
|
*/
|
||||||
|
static int
|
||||||
|
consensus_diff_queue_diff_work(consensus_cache_entry_t *diff_from,
|
||||||
|
consensus_cache_entry_t *diff_to)
|
||||||
|
{
|
||||||
|
tor_assert(in_main_thread());
|
||||||
|
|
||||||
|
consensus_cache_entry_incref(diff_from);
|
||||||
|
consensus_cache_entry_incref(diff_to);
|
||||||
|
|
||||||
|
consensus_diff_worker_job_t *job = tor_malloc_zero(sizeof(*job));
|
||||||
|
job->diff_from = diff_from;
|
||||||
|
job->diff_to = diff_to;
|
||||||
|
|
||||||
|
/* Make sure body is mapped. */
|
||||||
|
const uint8_t *body;
|
||||||
|
size_t bodylen;
|
||||||
|
int r1 = consensus_cache_entry_get_body(diff_from, &body, &bodylen);
|
||||||
|
int r2 = consensus_cache_entry_get_body(diff_to, &body, &bodylen);
|
||||||
|
if (r1 < 0 || r2 < 0)
|
||||||
|
goto err;
|
||||||
|
|
||||||
|
workqueue_entry_t *work;
|
||||||
|
work = cpuworker_queue_work(consensus_diff_worker_threadfn,
|
||||||
|
consensus_diff_worker_replyfn,
|
||||||
|
job);
|
||||||
|
if (!work)
|
||||||
|
goto err;
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
err:
|
||||||
|
consensus_diff_worker_job_free(job); // includes decrefs.
|
||||||
|
return -1;
|
||||||
|
}
|
||||||
|
|
||||||
38
src/or/consdiffmgr.h
Normal file
38
src/or/consdiffmgr.h
Normal file
@ -0,0 +1,38 @@
|
|||||||
|
/* Copyright (c) 2017, The Tor Project, Inc. */
|
||||||
|
/* See LICENSE for licensing information */
|
||||||
|
|
||||||
|
#ifndef TOR_CONSDIFFMGR_H
|
||||||
|
#define TOR_CONSDIFFMGR_H
|
||||||
|
|
||||||
|
/**
|
||||||
|
* Possible outcomes from trying to look up a given consensus diff.
|
||||||
|
*/
|
||||||
|
typedef enum consdiff_status_t {
|
||||||
|
CONSDIFF_AVAILABLE,
|
||||||
|
CONSDIFF_NOT_FOUND,
|
||||||
|
CONSDIFF_IN_PROGRESS,
|
||||||
|
} consdiff_status_t;
|
||||||
|
|
||||||
|
typedef struct consdiff_cfg_t {
|
||||||
|
uint32_t cache_max_age_hours;
|
||||||
|
uint32_t cache_max_num;
|
||||||
|
} consdiff_cfg_t;
|
||||||
|
|
||||||
|
struct consensus_cache_entry_t; // from conscache.h
|
||||||
|
|
||||||
|
int consdiffmgr_add_consensus(const char *consensus,
|
||||||
|
const networkstatus_t *as_parsed);
|
||||||
|
|
||||||
|
consdiff_status_t consdiffmgr_find_diff_from(
|
||||||
|
struct consensus_cache_entry_t **entry_out,
|
||||||
|
consensus_flavor_t flavor,
|
||||||
|
int digest_type,
|
||||||
|
const uint8_t *digest,
|
||||||
|
size_t digestlen);
|
||||||
|
void consdiffmgr_rescan(void);
|
||||||
|
int consdiffmgr_cleanup(void);
|
||||||
|
void consdiffmgr_configure(const consdiff_cfg_t *cfg);
|
||||||
|
void consdiffmgr_free_all(void);
|
||||||
|
|
||||||
|
#endif
|
||||||
|
|
||||||
@ -38,6 +38,7 @@ LIBTOR_A_SOURCES = \
|
|||||||
src/or/connection_or.c \
|
src/or/connection_or.c \
|
||||||
src/or/conscache.c \
|
src/or/conscache.c \
|
||||||
src/or/consdiff.c \
|
src/or/consdiff.c \
|
||||||
|
src/or/consdiffmgr.c \
|
||||||
src/or/control.c \
|
src/or/control.c \
|
||||||
src/or/cpuworker.c \
|
src/or/cpuworker.c \
|
||||||
src/or/dircollate.c \
|
src/or/dircollate.c \
|
||||||
@ -156,6 +157,7 @@ ORHEADERS = \
|
|||||||
src/or/connection_or.h \
|
src/or/connection_or.h \
|
||||||
src/or/conscache.h \
|
src/or/conscache.h \
|
||||||
src/or/consdiff.h \
|
src/or/consdiff.h \
|
||||||
|
src/or/consdiffmgr.h \
|
||||||
src/or/control.h \
|
src/or/control.h \
|
||||||
src/or/cpuworker.h \
|
src/or/cpuworker.h \
|
||||||
src/or/dircollate.h \
|
src/or/dircollate.h \
|
||||||
|
|||||||
Loading…
Reference in New Issue
Block a user