commit 3cddd6570c6c1e30b002893262680c3d3235d6c3 Author: Nick Mathewson <nickm@torproject.org> Date: Wed Aug 9 13:45:03 2017 -0400 Add a hashtable mapping to nodes from ed25519 ids --- src/or/nodelist.c | 126 +++++++++++++++++++++++++++++++++++++++++++++++++++++- src/or/nodelist.h | 3 ++ src/or/or.h | 9 ++++ 3 files changed, 137 insertions(+), 1 deletion(-) diff --git a/src/or/nodelist.c b/src/or/nodelist.c index 0fcaea626..93d362d8e 100644 --- a/src/or/nodelist.c +++ b/src/or/nodelist.c @@ -92,7 +92,14 @@ typedef struct nodelist_t { smartlist_t *nodes; /* Hash table to map from node ID digest to node. */ HT_HEAD(nodelist_map, node_t) nodes_by_id; - + /* Hash table to map from node Ed25519 ID to node. + * + * Whenever a node's routerinfo or microdescriptor is about to change, + * you should remove it from this map with node_remove_from_ed25519_map(). + * Whenever a node's routerinfo or microdescriptor has just chaned, + * you should add it to this map with node_add_to_ed25519_map(). + */ + HT_HEAD(nodelist_ed_map, node_t) nodes_by_ed_id; } nodelist_t; static inline unsigned int @@ -111,6 +118,23 @@ HT_PROTOTYPE(nodelist_map, node_t, ht_ent, node_id_hash, node_id_eq) HT_GENERATE2(nodelist_map, node_t, ht_ent, node_id_hash, node_id_eq, 0.6, tor_reallocarray_, tor_free_) +static inline unsigned int +node_ed_id_hash(const node_t *node) +{ + return (unsigned) siphash24g(node->ed25519_id.pubkey, ED25519_PUBKEY_LEN); +} + +static inline unsigned int +node_ed_id_eq(const node_t *node1, const node_t *node2) +{ + return ed25519_pubkey_eq(&node1->ed25519_id, &node2->ed25519_id); +} + +HT_PROTOTYPE(nodelist_ed_map, node_t, ed_ht_ent, node_ed_id_hash, + node_ed_id_eq) +HT_GENERATE2(nodelist_ed_map, node_t, ed_ht_ent, node_ed_id_hash, + node_ed_id_eq, 0.6, tor_reallocarray_, tor_free_) + /** The global nodelist. */ static nodelist_t *the_nodelist=NULL; @@ -121,6 +145,7 @@ init_nodelist(void) if (PREDICT_UNLIKELY(the_nodelist == NULL)) { the_nodelist = tor_malloc_zero(sizeof(nodelist_t)); HT_INIT(nodelist_map, &the_nodelist->nodes_by_id); + HT_INIT(nodelist_ed_map, &the_nodelist->nodes_by_ed_id); the_nodelist->nodes = smartlist_new(); } } @@ -138,6 +163,21 @@ node_get_mutable_by_id(const char *identity_digest) return node; } +/** As node_get_by_ed25519_id, but returns a non-const pointer */ +node_t * +node_get_mutable_by_ed25519_id(const ed25519_public_key_t *ed_id) +{ + node_t search, *node; + if (PREDICT_UNLIKELY(the_nodelist == NULL)) + return NULL; + if (BUG(ed_id == NULL) || BUG(ed25519_public_key_is_zero(ed_id))) + return NULL; + + memcpy(&search.ed25519_id, ed_id, sizeof(search.ed25519_id)); + node = HT_FIND(nodelist_ed_map, &the_nodelist->nodes_by_ed_id, &search); + return node; +} + /** Return the node_t whose identity is <b>identity_digest</b>, or NULL * if no such node exists. */ MOCK_IMPL(const node_t *, @@ -146,6 +186,14 @@ node_get_by_id,(const char *identity_digest)) return node_get_mutable_by_id(identity_digest); } +/** Return the node_t whose ed25519 identity is <b>ed_id</b>, or NULL + * if no such node exists. */ +MOCK_IMPL(const node_t *, +node_get_by_ed25519_id,(const ed25519_public_key_t *ed_id)) +{ + return node_get_mutable_by_ed25519_id(ed_id); +} + /** Internal: return the node_t whose identity_digest is * <b>identity_digest</b>. If none exists, create a new one, add it to the * nodelist, and return it. @@ -173,6 +221,67 @@ node_get_or_create(const char *identity_digest) return node; } +/** Remove <b>node</b> from the ed25519 map (if it present), and + * set its ed25519_id field to zero. */ +static int +node_remove_from_ed25519_map(node_t *node) +{ + tor_assert(the_nodelist); + tor_assert(node); + + if (ed25519_public_key_is_zero(&node->ed25519_id)) { + return 0; + } + + int rv = 0; + node_t *search = + HT_FIND(nodelist_ed_map, &the_nodelist->nodes_by_ed_id, node); + if (BUG(search != node)) { + goto clear_and_return; + } + + search = HT_REMOVE(nodelist_ed_map, &the_nodelist->nodes_by_ed_id, node); + tor_assert(search == node); + rv = 1; + + clear_and_return: + memset(&node->ed25519_id, 0, sizeof(node->ed25519_id)); + return rv; +} + +/** If <b>node</b> has an ed25519 id, and it is not already in the ed25519 id + * map, set its ed25519_id field, and add it to the ed25519 map. + */ +static int +node_add_to_ed25519_map(node_t *node) +{ + tor_assert(the_nodelist); + tor_assert(node); + + if (! ed25519_public_key_is_zero(&node->ed25519_id)) { + return 0; + } + + const ed25519_public_key_t *key = node_get_ed25519_id(node); + if (!key) { + return 0; + } + + node_t *old; + memcpy(&node->ed25519_id, key, sizeof(node->ed25519_id)); + old = HT_FIND(nodelist_ed_map, &the_nodelist->nodes_by_ed_id, node); + if (BUG(old)) { + /* XXXX order matters here, and this may mean that authorities aren't + * pinning. */ + if (old != node) + memset(&node->ed25519_id, 0, sizeof(node->ed25519_id)); + return 0; + } + + HT_INSERT(nodelist_ed_map, &the_nodelist->nodes_by_ed_id, node); + return 1; +} + /* For a given <b>node</b> for the consensus <b>ns</b>, set the hsdir index * for the node, both current and next if possible. This can only fails if the * node_t ed25519 identity key can't be found which would be a bug. */ @@ -262,6 +371,8 @@ nodelist_set_routerinfo(routerinfo_t *ri, routerinfo_t **ri_old_out) id_digest = ri->cache_info.identity_digest; node = node_get_or_create(id_digest); + node_remove_from_ed25519_map(node); + if (node->ri) { if (!routers_have_same_or_addrs(node->ri, ri)) { node_addrs_changed(node); @@ -275,6 +386,8 @@ nodelist_set_routerinfo(routerinfo_t *ri, routerinfo_t **ri_old_out) } node->ri = ri; + node_add_to_ed25519_map(node); + if (node->country == -1) node_set_country(node); @@ -318,8 +431,10 @@ nodelist_add_microdesc(microdesc_t *md) return NULL; node = node_get_mutable_by_id(rs->identity_digest); if (node) { + node_remove_from_ed25519_map(node); if (node->md) node->md->held_by_nodes--; + node->md = md; md->held_by_nodes++; /* Setting the HSDir index requires the ed25519 identity key which can @@ -328,7 +443,9 @@ nodelist_add_microdesc(microdesc_t *md) if (rs->supports_v3_hsdir) { node_set_hsdir_index(node, ns); } + node_add_to_ed25519_map(node); } + return node; } @@ -356,12 +473,14 @@ nodelist_set_consensus(networkstatus_t *ns) if (ns->flavor == FLAV_MICRODESC) { if (node->md == NULL || tor_memneq(node->md->digest,rs->descriptor_digest,DIGEST256_LEN)) { + node_remove_from_ed25519_map(node); if (node->md) node->md->held_by_nodes--; node->md = microdesc_cache_lookup_by_digest256(NULL, rs->descriptor_digest); if (node->md) node->md->held_by_nodes++; + node_add_to_ed25519_map(node); } } @@ -426,6 +545,9 @@ nodelist_remove_microdesc(const char *identity_digest, microdesc_t *md) if (node && node->md == md) { node->md = NULL; md->held_by_nodes--; + if (! node_get_ed25519_id(node)) { + node_remove_from_ed25519_map(node); + } } } @@ -454,6 +576,7 @@ nodelist_drop_node(node_t *node, int remove_from_ht) tmp = HT_REMOVE(nodelist_map, &the_nodelist->nodes_by_id, node); tor_assert(tmp == node); } + node_remove_from_ed25519_map(node); idx = node->nodelist_idx; tor_assert(idx >= 0); @@ -537,6 +660,7 @@ nodelist_free_all(void) return; HT_CLEAR(nodelist_map, &the_nodelist->nodes_by_id); + HT_CLEAR(nodelist_ed_map, &the_nodelist->nodes_by_ed_id); SMARTLIST_FOREACH_BEGIN(the_nodelist->nodes, node_t *, node) { node->nodelist_idx = -1; node_free(node); diff --git a/src/or/nodelist.h b/src/or/nodelist.h index 405b79d82..20df37b51 100644 --- a/src/or/nodelist.h +++ b/src/or/nodelist.h @@ -18,6 +18,9 @@ node_t *node_get_mutable_by_id(const char *identity_digest); MOCK_DECL(const node_t *, node_get_by_id, (const char *identity_digest)); +node_t *node_get_mutable_by_ed25519_id(const ed25519_public_key_t *ed_id); +MOCK_DECL(const node_t *, node_get_by_ed25519_id, + (const ed25519_public_key_t *ed_id)); const node_t *node_get_by_hex_id(const char *identity_digest); node_t *nodelist_set_routerinfo(routerinfo_t *ri, routerinfo_t **ri_old_out); node_t *nodelist_add_microdesc(microdesc_t *md); diff --git a/src/or/or.h b/src/or/or.h index ff11c7279..9449e87e1 100644 --- a/src/or/or.h +++ b/src/or/or.h @@ -2443,6 +2443,8 @@ typedef struct node_t { /** Used to look up the node_t by its identity digest. */ HT_ENTRY(node_t) ht_ent; + /** Used to look up the node_t by its ed25519 identity digest. */ + HT_ENTRY(node_t) ed_ht_ent; /** Position of the node within the list of nodes */ int nodelist_idx; @@ -2450,6 +2452,13 @@ typedef struct node_t { * identity may exist at a time. */ char identity[DIGEST_LEN]; + /** The ed25519 identity of this node_t. This field is nonzero iff we + * currently have an ed25519 identity for this node in either md or ri, + * _and_ this node has been inserted to the ed25519-to-node map in the + * nodelist. + */ + ed25519_public_key_t ed25519_id; + microdesc_t *md; routerinfo_t *ri; routerstatus_t *rs;