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tor/src/or/nodelist.c
Nick Mathewson bbaa7d09a0 Merge remote-tracking branch 'teor/reject-tap-v6'
2016-08-29 15:02:11 -04:00

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/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2016, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file nodelist.c
*
* \brief Structures and functions for tracking what we know about the routers
* on the Tor network, and correlating information from networkstatus,
* routerinfo, and microdescs.
*/
#include "or.h"
#include "address.h"
#include "config.h"
#include "control.h"
#include "dirserv.h"
#include "geoip.h"
#include "main.h"
#include "microdesc.h"
#include "networkstatus.h"
#include "nodelist.h"
#include "policies.h"
#include "rendservice.h"
#include "router.h"
#include "routerlist.h"
#include "routerset.h"
#include <string.h>
static void nodelist_drop_node(node_t *node, int remove_from_ht);
static void node_free(node_t *node);
/** count_usable_descriptors counts descriptors with these flag(s)
*/
typedef enum {
/* All descriptors regardless of flags */
USABLE_DESCRIPTOR_ALL = 0,
/* Only descriptors with the Exit flag */
USABLE_DESCRIPTOR_EXIT_ONLY = 1
} usable_descriptor_t;
static void count_usable_descriptors(int *num_present,
int *num_usable,
smartlist_t *descs_out,
const networkstatus_t *consensus,
const or_options_t *options,
time_t now,
routerset_t *in_set,
usable_descriptor_t exit_only);
static void update_router_have_minimum_dir_info(void);
static double get_frac_paths_needed_for_circs(const or_options_t *options,
const networkstatus_t *ns);
/** A nodelist_t holds a node_t object for every router we're "willing to use
* for something". Specifically, it should hold a node_t for every node that
* is currently in the routerlist, or currently in the consensus we're using.
*/
typedef struct nodelist_t {
/* A list of all the nodes. */
smartlist_t *nodes;
/* Hash table to map from node ID digest to node. */
HT_HEAD(nodelist_map, node_t) nodes_by_id;
} nodelist_t;
static inline unsigned int
node_id_hash(const node_t *node)
{
return (unsigned) siphash24g(node->identity, DIGEST_LEN);
}
static inline unsigned int
node_id_eq(const node_t *node1, const node_t *node2)
{
return tor_memeq(node1->identity, node2->identity, DIGEST_LEN);
}
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_)
/** The global nodelist. */
static nodelist_t *the_nodelist=NULL;
/** Create an empty nodelist if we haven't done so already. */
static void
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);
the_nodelist->nodes = smartlist_new();
}
}
/** As node_get_by_id, but returns a non-const pointer */
node_t *
node_get_mutable_by_id(const char *identity_digest)
{
node_t search, *node;
if (PREDICT_UNLIKELY(the_nodelist == NULL))
return NULL;
memcpy(&search.identity, identity_digest, DIGEST_LEN);
node = HT_FIND(nodelist_map, &the_nodelist->nodes_by_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 *,
node_get_by_id,(const char *identity_digest))
{
return node_get_mutable_by_id(identity_digest);
}
/** 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.
*
* Requires that the nodelist be initialized.
*/
static node_t *
node_get_or_create(const char *identity_digest)
{
node_t *node;
if ((node = node_get_mutable_by_id(identity_digest)))
return node;
node = tor_malloc_zero(sizeof(node_t));
memcpy(node->identity, identity_digest, DIGEST_LEN);
HT_INSERT(nodelist_map, &the_nodelist->nodes_by_id, node);
smartlist_add(the_nodelist->nodes, node);
node->nodelist_idx = smartlist_len(the_nodelist->nodes) - 1;
node->country = -1;
return node;
}
/** Called when a node's address changes. */
static void
node_addrs_changed(node_t *node)
{
node->last_reachable = node->last_reachable6 = 0;
node->country = -1;
}
/** Add <b>ri</b> to an appropriate node in the nodelist. If we replace an
* old routerinfo, and <b>ri_old_out</b> is not NULL, set *<b>ri_old_out</b>
* to the previous routerinfo.
*/
node_t *
nodelist_set_routerinfo(routerinfo_t *ri, routerinfo_t **ri_old_out)
{
node_t *node;
const char *id_digest;
int had_router = 0;
tor_assert(ri);
init_nodelist();
id_digest = ri->cache_info.identity_digest;
node = node_get_or_create(id_digest);
if (node->ri) {
if (!routers_have_same_or_addrs(node->ri, ri)) {
node_addrs_changed(node);
}
had_router = 1;
if (ri_old_out)
*ri_old_out = node->ri;
} else {
if (ri_old_out)
*ri_old_out = NULL;
}
node->ri = ri;
if (node->country == -1)
node_set_country(node);
if (authdir_mode(get_options()) && !had_router) {
const char *discard=NULL;
uint32_t status = dirserv_router_get_status(ri, &discard, LOG_INFO);
dirserv_set_node_flags_from_authoritative_status(node, status);
}
return node;
}
/** Set the appropriate node_t to use <b>md</b> as its microdescriptor.
*
* Called when a new microdesc has arrived and the usable consensus flavor
* is "microdesc".
**/
node_t *
nodelist_add_microdesc(microdesc_t *md)
{
networkstatus_t *ns =
networkstatus_get_latest_consensus_by_flavor(FLAV_MICRODESC);
const routerstatus_t *rs;
node_t *node;
if (ns == NULL)
return NULL;
init_nodelist();
/* Microdescriptors don't carry an identity digest, so we need to figure
* it out by looking up the routerstatus. */
rs = router_get_consensus_status_by_descriptor_digest(ns, md->digest);
if (rs == NULL)
return NULL;
node = node_get_mutable_by_id(rs->identity_digest);
if (node) {
if (node->md)
node->md->held_by_nodes--;
node->md = md;
md->held_by_nodes++;
}
return node;
}
/** Tell the nodelist that the current usable consensus is <b>ns</b>.
* This makes the nodelist change all of the routerstatus entries for
* the nodes, drop nodes that no longer have enough info to get used,
* and grab microdescriptors into nodes as appropriate.
*/
void
nodelist_set_consensus(networkstatus_t *ns)
{
const or_options_t *options = get_options();
int authdir = authdir_mode_v3(options);
init_nodelist();
if (ns->flavor == FLAV_MICRODESC)
(void) get_microdesc_cache(); /* Make sure it exists first. */
SMARTLIST_FOREACH(the_nodelist->nodes, node_t *, node,
node->rs = NULL);
SMARTLIST_FOREACH_BEGIN(ns->routerstatus_list, routerstatus_t *, rs) {
node_t *node = node_get_or_create(rs->identity_digest);
node->rs = rs;
if (ns->flavor == FLAV_MICRODESC) {
if (node->md == NULL ||
tor_memneq(node->md->digest,rs->descriptor_digest,DIGEST256_LEN)) {
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_set_country(node);
/* If we're not an authdir, believe others. */
if (!authdir) {
node->is_valid = rs->is_valid;
node->is_running = rs->is_flagged_running;
node->is_fast = rs->is_fast;
node->is_stable = rs->is_stable;
node->is_possible_guard = rs->is_possible_guard;
node->is_exit = rs->is_exit;
node->is_bad_exit = rs->is_bad_exit;
node->is_hs_dir = rs->is_hs_dir;
node->ipv6_preferred = 0;
if (fascist_firewall_prefer_ipv6_orport(options) &&
(tor_addr_is_null(&rs->ipv6_addr) == 0 ||
(node->md && tor_addr_is_null(&node->md->ipv6_addr) == 0)))
node->ipv6_preferred = 1;
}
} SMARTLIST_FOREACH_END(rs);
nodelist_purge();
if (! authdir) {
SMARTLIST_FOREACH_BEGIN(the_nodelist->nodes, node_t *, node) {
/* We have no routerstatus for this router. Clear flags so we can skip
* it, maybe.*/
if (!node->rs) {
tor_assert(node->ri); /* if it had only an md, or nothing, purge
* would have removed it. */
if (node->ri->purpose == ROUTER_PURPOSE_GENERAL) {
/* Clear all flags. */
node->is_valid = node->is_running = node->is_hs_dir =
node->is_fast = node->is_stable =
node->is_possible_guard = node->is_exit =
node->is_bad_exit = node->ipv6_preferred = 0;
}
}
} SMARTLIST_FOREACH_END(node);
}
}
/** Helper: return true iff a node has a usable amount of information*/
static inline int
node_is_usable(const node_t *node)
{
return (node->rs) || (node->ri);
}
/** Tell the nodelist that <b>md</b> is no longer a microdescriptor for the
* node with <b>identity_digest</b>. */
void
nodelist_remove_microdesc(const char *identity_digest, microdesc_t *md)
{
node_t *node = node_get_mutable_by_id(identity_digest);
if (node && node->md == md) {
node->md = NULL;
md->held_by_nodes--;
}
}
/** Tell the nodelist that <b>ri</b> is no longer in the routerlist. */
void
nodelist_remove_routerinfo(routerinfo_t *ri)
{
node_t *node = node_get_mutable_by_id(ri->cache_info.identity_digest);
if (node && node->ri == ri) {
node->ri = NULL;
if (! node_is_usable(node)) {
nodelist_drop_node(node, 1);
node_free(node);
}
}
}
/** Remove <b>node</b> from the nodelist. (Asserts that it was there to begin
* with.) */
static void
nodelist_drop_node(node_t *node, int remove_from_ht)
{
node_t *tmp;
int idx;
if (remove_from_ht) {
tmp = HT_REMOVE(nodelist_map, &the_nodelist->nodes_by_id, node);
tor_assert(tmp == node);
}
idx = node->nodelist_idx;
tor_assert(idx >= 0);
tor_assert(node == smartlist_get(the_nodelist->nodes, idx));
smartlist_del(the_nodelist->nodes, idx);
if (idx < smartlist_len(the_nodelist->nodes)) {
tmp = smartlist_get(the_nodelist->nodes, idx);
tmp->nodelist_idx = idx;
}
node->nodelist_idx = -1;
}
/** Return a newly allocated smartlist of the nodes that have <b>md</b> as
* their microdescriptor. */
smartlist_t *
nodelist_find_nodes_with_microdesc(const microdesc_t *md)
{
smartlist_t *result = smartlist_new();
if (the_nodelist == NULL)
return result;
SMARTLIST_FOREACH_BEGIN(the_nodelist->nodes, node_t *, node) {
if (node->md == md) {
smartlist_add(result, node);
}
} SMARTLIST_FOREACH_END(node);
return result;
}
/** Release storage held by <b>node</b> */
static void
node_free(node_t *node)
{
if (!node)
return;
if (node->md)
node->md->held_by_nodes--;
tor_assert(node->nodelist_idx == -1);
tor_free(node);
}
/** Remove all entries from the nodelist that don't have enough info to be
* usable for anything. */
void
nodelist_purge(void)
{
node_t **iter;
if (PREDICT_UNLIKELY(the_nodelist == NULL))
return;
/* Remove the non-usable nodes. */
for (iter = HT_START(nodelist_map, &the_nodelist->nodes_by_id); iter; ) {
node_t *node = *iter;
if (node->md && !node->rs) {
/* An md is only useful if there is an rs. */
node->md->held_by_nodes--;
node->md = NULL;
}
if (node_is_usable(node)) {
iter = HT_NEXT(nodelist_map, &the_nodelist->nodes_by_id, iter);
} else {
iter = HT_NEXT_RMV(nodelist_map, &the_nodelist->nodes_by_id, iter);
nodelist_drop_node(node, 0);
node_free(node);
}
}
nodelist_assert_ok();
}
/** Release all storage held by the nodelist. */
void
nodelist_free_all(void)
{
if (PREDICT_UNLIKELY(the_nodelist == NULL))
return;
HT_CLEAR(nodelist_map, &the_nodelist->nodes_by_id);
SMARTLIST_FOREACH_BEGIN(the_nodelist->nodes, node_t *, node) {
node->nodelist_idx = -1;
node_free(node);
} SMARTLIST_FOREACH_END(node);
smartlist_free(the_nodelist->nodes);
tor_free(the_nodelist);
}
/** Check that the nodelist is internally consistent, and consistent with
* the directory info it's derived from.
*/
void
nodelist_assert_ok(void)
{
routerlist_t *rl = router_get_routerlist();
networkstatus_t *ns = networkstatus_get_latest_consensus();
digestmap_t *dm;
if (!the_nodelist)
return;
dm = digestmap_new();
/* every routerinfo in rl->routers should be in the nodelist. */
if (rl) {
SMARTLIST_FOREACH_BEGIN(rl->routers, routerinfo_t *, ri) {
const node_t *node = node_get_by_id(ri->cache_info.identity_digest);
tor_assert(node && node->ri == ri);
tor_assert(fast_memeq(ri->cache_info.identity_digest,
node->identity, DIGEST_LEN));
tor_assert(! digestmap_get(dm, node->identity));
digestmap_set(dm, node->identity, (void*)node);
} SMARTLIST_FOREACH_END(ri);
}
/* every routerstatus in ns should be in the nodelist */
if (ns) {
SMARTLIST_FOREACH_BEGIN(ns->routerstatus_list, routerstatus_t *, rs) {
const node_t *node = node_get_by_id(rs->identity_digest);
tor_assert(node && node->rs == rs);
tor_assert(fast_memeq(rs->identity_digest, node->identity, DIGEST_LEN));
digestmap_set(dm, node->identity, (void*)node);
if (ns->flavor == FLAV_MICRODESC) {
/* If it's a microdesc consensus, every entry that has a
* microdescriptor should be in the nodelist.
*/
microdesc_t *md =
microdesc_cache_lookup_by_digest256(NULL, rs->descriptor_digest);
tor_assert(md == node->md);
if (md)
tor_assert(md->held_by_nodes >= 1);
}
} SMARTLIST_FOREACH_END(rs);
}
/* The nodelist should have no other entries, and its entries should be
* well-formed. */
SMARTLIST_FOREACH_BEGIN(the_nodelist->nodes, node_t *, node) {
tor_assert(digestmap_get(dm, node->identity) != NULL);
tor_assert(node_sl_idx == node->nodelist_idx);
} SMARTLIST_FOREACH_END(node);
tor_assert((long)smartlist_len(the_nodelist->nodes) ==
(long)HT_SIZE(&the_nodelist->nodes_by_id));
digestmap_free(dm, NULL);
}
/** Return a list of a node_t * for every node we know about. The caller
* MUST NOT modify the list. (You can set and clear flags in the nodes if
* you must, but you must not add or remove nodes.) */
MOCK_IMPL(smartlist_t *,
nodelist_get_list,(void))
{
init_nodelist();
return the_nodelist->nodes;
}
/** Given a hex-encoded nickname of the format DIGEST, $DIGEST, $DIGEST=name,
* or $DIGEST~name, return the node with the matching identity digest and
* nickname (if any). Return NULL if no such node exists, or if <b>hex_id</b>
* is not well-formed. */
const node_t *
node_get_by_hex_id(const char *hex_id)
{
char digest_buf[DIGEST_LEN];
char nn_buf[MAX_NICKNAME_LEN+1];
char nn_char='\0';
if (hex_digest_nickname_decode(hex_id, digest_buf, &nn_char, nn_buf)==0) {
const node_t *node = node_get_by_id(digest_buf);
if (!node)
return NULL;
if (nn_char) {
const char *real_name = node_get_nickname(node);
if (!real_name || strcasecmp(real_name, nn_buf))
return NULL;
if (nn_char == '=') {
const char *named_id =
networkstatus_get_router_digest_by_nickname(nn_buf);
if (!named_id || tor_memneq(named_id, digest_buf, DIGEST_LEN))
return NULL;
}
}
return node;
}
return NULL;
}
/** Given a nickname (possibly verbose, possibly a hexadecimal digest), return
* the corresponding node_t, or NULL if none exists. Warn the user if
* <b>warn_if_unnamed</b> is set, and they have specified a router by
* nickname, but the Named flag isn't set for that router. */
MOCK_IMPL(const node_t *,
node_get_by_nickname,(const char *nickname, int warn_if_unnamed))
{
if (!the_nodelist)
return NULL;
/* Handle these cases: DIGEST, $DIGEST, $DIGEST=name, $DIGEST~name. */
{
const node_t *node;
if ((node = node_get_by_hex_id(nickname)) != NULL)
return node;
}
if (!strcasecmp(nickname, UNNAMED_ROUTER_NICKNAME))
return NULL;
/* Okay, so if we get here, the nickname is just a nickname. Is there
* a binding for it in the consensus? */
{
const char *named_id =
networkstatus_get_router_digest_by_nickname(nickname);
if (named_id)
return node_get_by_id(named_id);
}
/* Is it marked as owned-by-someone-else? */
if (networkstatus_nickname_is_unnamed(nickname)) {
log_info(LD_GENERAL, "The name %s is listed as Unnamed: there is some "
"router that holds it, but not one listed in the current "
"consensus.", escaped(nickname));
return NULL;
}
/* Okay, so the name is not canonical for anybody. */
{
smartlist_t *matches = smartlist_new();
const node_t *choice = NULL;
SMARTLIST_FOREACH_BEGIN(the_nodelist->nodes, node_t *, node) {
if (!strcasecmp(node_get_nickname(node), nickname))
smartlist_add(matches, node);
} SMARTLIST_FOREACH_END(node);
if (smartlist_len(matches)>1 && warn_if_unnamed) {
int any_unwarned = 0;
SMARTLIST_FOREACH_BEGIN(matches, node_t *, node) {
if (!node->name_lookup_warned) {
node->name_lookup_warned = 1;
any_unwarned = 1;
}
} SMARTLIST_FOREACH_END(node);
if (any_unwarned) {
log_warn(LD_CONFIG, "There are multiple matches for the name %s, "
"but none is listed as Named in the directory consensus. "
"Choosing one arbitrarily.", nickname);
}
} else if (smartlist_len(matches)==1 && warn_if_unnamed) {
char fp[HEX_DIGEST_LEN+1];
node_t *node = smartlist_get(matches, 0);
if (! node->name_lookup_warned) {
base16_encode(fp, sizeof(fp), node->identity, DIGEST_LEN);
log_warn(LD_CONFIG,
"You specified a server \"%s\" by name, but the directory "
"authorities do not have any key registered for this "
"nickname -- so it could be used by any server, not just "
"the one you meant. "
"To make sure you get the same server in the future, refer "
"to it by key, as \"$%s\".", nickname, fp);
node->name_lookup_warned = 1;
}
}
if (smartlist_len(matches))
choice = smartlist_get(matches, 0);
smartlist_free(matches);
return choice;
}
}
/** Return the nickname of <b>node</b>, or NULL if we can't find one. */
const char *
node_get_nickname(const node_t *node)
{
tor_assert(node);
if (node->rs)
return node->rs->nickname;
else if (node->ri)
return node->ri->nickname;
else
return NULL;
}
/** Return true iff the nickname of <b>node</b> is canonical, based on the
* latest consensus. */
int
node_is_named(const node_t *node)
{
const char *named_id;
const char *nickname = node_get_nickname(node);
if (!nickname)
return 0;
named_id = networkstatus_get_router_digest_by_nickname(nickname);
if (!named_id)
return 0;
return tor_memeq(named_id, node->identity, DIGEST_LEN);
}
/** Return true iff <b>node</b> appears to be a directory authority or
* directory cache */
int
node_is_dir(const node_t *node)
{
if (node->rs) {
routerstatus_t * rs = node->rs;
/* This is true if supports_tunnelled_dir_requests is true which
* indicates that we support directory request tunnelled or through the
* DirPort. */
return rs->is_v2_dir;
} else if (node->ri) {
routerinfo_t * ri = node->ri;
/* Both tunnelled request is supported or DirPort is set. */
return ri->supports_tunnelled_dir_requests;
} else {
return 0;
}
}
/** Return true iff <b>node</b> has either kind of usable descriptor -- that
* is, a routerdescriptor or a microdescriptor. */
int
node_has_descriptor(const node_t *node)
{
return (node->ri ||
(node->rs && node->md));
}
/** Return the router_purpose of <b>node</b>. */
int
node_get_purpose(const node_t *node)
{
if (node->ri)
return node->ri->purpose;
else
return ROUTER_PURPOSE_GENERAL;
}
/** Compute the verbose ("extended") nickname of <b>node</b> and store it
* into the MAX_VERBOSE_NICKNAME_LEN+1 character buffer at
* <b>verbose_name_out</b> */
void
node_get_verbose_nickname(const node_t *node,
char *verbose_name_out)
{
const char *nickname = node_get_nickname(node);
int is_named = node_is_named(node);
verbose_name_out[0] = '$';
base16_encode(verbose_name_out+1, HEX_DIGEST_LEN+1, node->identity,
DIGEST_LEN);
if (!nickname)
return;
verbose_name_out[1+HEX_DIGEST_LEN] = is_named ? '=' : '~';
strlcpy(verbose_name_out+1+HEX_DIGEST_LEN+1, nickname, MAX_NICKNAME_LEN+1);
}
/** Compute the verbose ("extended") nickname of node with
* given <b>id_digest</b> and store it into the MAX_VERBOSE_NICKNAME_LEN+1
* character buffer at <b>verbose_name_out</b>
*
* If node_get_by_id() returns NULL, base 16 encoding of
* <b>id_digest</b> is returned instead. */
void
node_get_verbose_nickname_by_id(const char *id_digest,
char *verbose_name_out)
{
const node_t *node = node_get_by_id(id_digest);
if (!node) {
verbose_name_out[0] = '$';
base16_encode(verbose_name_out+1, HEX_DIGEST_LEN+1, id_digest, DIGEST_LEN);
} else {
node_get_verbose_nickname(node, verbose_name_out);
}
}
/** Return true iff it seems that <b>node</b> allows circuits to exit
* through it directlry from the client. */
int
node_allows_single_hop_exits(const node_t *node)
{
if (node && node->ri)
return node->ri->allow_single_hop_exits;
else
return 0;
}
/** Return true iff it seems that <b>node</b> has an exit policy that doesn't
* actually permit anything to exit, or we don't know its exit policy */
int
node_exit_policy_rejects_all(const node_t *node)
{
if (node->rejects_all)
return 1;
if (node->ri)
return node->ri->policy_is_reject_star;
else if (node->md)
return node->md->exit_policy == NULL ||
short_policy_is_reject_star(node->md->exit_policy);
else
return 1;
}
/** Return true iff the exit policy for <b>node</b> is such that we can treat
* rejecting an address of type <b>family</b> unexpectedly as a sign of that
* node's failure. */
int
node_exit_policy_is_exact(const node_t *node, sa_family_t family)
{
if (family == AF_UNSPEC) {
return 1; /* Rejecting an address but not telling us what address
* is a bad sign. */
} else if (family == AF_INET) {
return node->ri != NULL;
} else if (family == AF_INET6) {
return 0;
}
tor_fragile_assert();
return 1;
}
/* Check if the "addr" and port_field fields from r are a valid non-listening
* address/port. If so, set valid to true and add a newly allocated
* tor_addr_port_t containing "addr" and port_field to sl.
* "addr" is an IPv4 host-order address and port_field is a uint16_t.
* r is typically a routerinfo_t or routerstatus_t.
*/
#define SL_ADD_NEW_IPV4_AP(r, port_field, sl, valid) \
STMT_BEGIN \
if (tor_addr_port_is_valid_ipv4h((r)->addr, (r)->port_field, 0)) { \
valid = 1; \
tor_addr_port_t *ap = tor_malloc(sizeof(tor_addr_port_t)); \
tor_addr_from_ipv4h(&ap->addr, (r)->addr); \
ap->port = (r)->port_field; \
smartlist_add((sl), ap); \
} \
STMT_END
/* Check if the "addr" and port_field fields from r are a valid non-listening
* address/port. If so, set valid to true and add a newly allocated
* tor_addr_port_t containing "addr" and port_field to sl.
* "addr" is a tor_addr_t and port_field is a uint16_t.
* r is typically a routerinfo_t or routerstatus_t.
*/
#define SL_ADD_NEW_IPV6_AP(r, port_field, sl, valid) \
STMT_BEGIN \
if (tor_addr_port_is_valid(&(r)->ipv6_addr, (r)->port_field, 0)) { \
valid = 1; \
tor_addr_port_t *ap = tor_malloc(sizeof(tor_addr_port_t)); \
tor_addr_copy(&ap->addr, &(r)->ipv6_addr); \
ap->port = (r)->port_field; \
smartlist_add((sl), ap); \
} \
STMT_END
/** Return list of tor_addr_port_t with all OR ports (in the sense IP
* addr + TCP port) for <b>node</b>. Caller must free all elements
* using tor_free() and free the list using smartlist_free().
*
* XXX this is potentially a memory fragmentation hog -- if on
* critical path consider the option of having the caller allocate the
* memory
*/
smartlist_t *
node_get_all_orports(const node_t *node)
{
smartlist_t *sl = smartlist_new();
int valid = 0;
/* Find a valid IPv4 address and port */
if (node->ri != NULL) {
SL_ADD_NEW_IPV4_AP(node->ri, or_port, sl, valid);
}
/* If we didn't find a valid address/port in the ri, try the rs */
if (!valid && node->rs != NULL) {
SL_ADD_NEW_IPV4_AP(node->rs, or_port, sl, valid);
}
/* Find a valid IPv6 address and port */
valid = 0;
if (node->ri != NULL) {
SL_ADD_NEW_IPV6_AP(node->ri, ipv6_orport, sl, valid);
}
if (!valid && node->rs != NULL) {
SL_ADD_NEW_IPV6_AP(node->rs, ipv6_orport, sl, valid);
}
if (!valid && node->md != NULL) {
SL_ADD_NEW_IPV6_AP(node->md, ipv6_orport, sl, valid);
}
return sl;
}
#undef SL_ADD_NEW_IPV4_AP
#undef SL_ADD_NEW_IPV6_AP
/** Wrapper around node_get_prim_orport for backward
compatibility. */
void
node_get_addr(const node_t *node, tor_addr_t *addr_out)
{
tor_addr_port_t ap;
node_get_prim_orport(node, &ap);
tor_addr_copy(addr_out, &ap.addr);
}
/** Return the host-order IPv4 address for <b>node</b>, or 0 if it doesn't
* seem to have one. */
uint32_t
node_get_prim_addr_ipv4h(const node_t *node)
{
/* Don't check the ORPort or DirPort, as this function isn't port-specific,
* and the node might have a valid IPv4 address, yet have a zero
* ORPort or DirPort.
*/
if (node->ri && tor_addr_is_valid_ipv4h(node->ri->addr, 0)) {
return node->ri->addr;
} else if (node->rs && tor_addr_is_valid_ipv4h(node->rs->addr, 0)) {
return node->rs->addr;
}
return 0;
}
/** Copy a string representation of an IP address for <b>node</b> into
* the <b>len</b>-byte buffer at <b>buf</b>. */
void
node_get_address_string(const node_t *node, char *buf, size_t len)
{
uint32_t ipv4_addr = node_get_prim_addr_ipv4h(node);
if (tor_addr_is_valid_ipv4h(ipv4_addr, 0)) {
tor_addr_t addr;
tor_addr_from_ipv4h(&addr, ipv4_addr);
tor_addr_to_str(buf, &addr, len, 0);
} else if (len > 0) {
buf[0] = '\0';
}
}
/** Return <b>node</b>'s declared uptime, or -1 if it doesn't seem to have
* one. */
long
node_get_declared_uptime(const node_t *node)
{
if (node->ri)
return node->ri->uptime;
else
return -1;
}
/** Return <b>node</b>'s platform string, or NULL if we don't know it. */
const char *
node_get_platform(const node_t *node)
{
/* If we wanted, we could record the version in the routerstatus_t, since
* the consensus lists it. We don't, though, so this function just won't
* work with microdescriptors. */
if (node->ri)
return node->ri->platform;
else
return NULL;
}
/** Return <b>node</b>'s time of publication, or 0 if we don't have one. */
time_t
node_get_published_on(const node_t *node)
{
if (node->ri)
return node->ri->cache_info.published_on;
else
return 0;
}
/** Return true iff <b>node</b> is one representing this router. */
int
node_is_me(const node_t *node)
{
return router_digest_is_me(node->identity);
}
/** Return <b>node</b> declared family (as a list of names), or NULL if
* the node didn't declare a family. */
const smartlist_t *
node_get_declared_family(const node_t *node)
{
if (node->ri && node->ri->declared_family)
return node->ri->declared_family;
else if (node->md && node->md->family)
return node->md->family;
else
return NULL;
}
/* Does this node have a valid IPv6 address?
* Prefer node_has_ipv6_orport() or node_has_ipv6_dirport() for
* checking specific ports. */
int
node_has_ipv6_addr(const node_t *node)
{
/* Don't check the ORPort or DirPort, as this function isn't port-specific,
* and the node might have a valid IPv6 address, yet have a zero
* ORPort or DirPort.
*/
if (node->ri && tor_addr_is_valid(&node->ri->ipv6_addr, 0))
return 1;
if (node->rs && tor_addr_is_valid(&node->rs->ipv6_addr, 0))
return 1;
if (node->md && tor_addr_is_valid(&node->md->ipv6_addr, 0))
return 1;
return 0;
}
/* Does this node have a valid IPv6 ORPort? */
int
node_has_ipv6_orport(const node_t *node)
{
tor_addr_port_t ipv6_orport;
node_get_pref_ipv6_orport(node, &ipv6_orport);
return tor_addr_port_is_valid_ap(&ipv6_orport, 0);
}
/* Does this node have a valid IPv6 DirPort? */
int
node_has_ipv6_dirport(const node_t *node)
{
tor_addr_port_t ipv6_dirport;
node_get_pref_ipv6_dirport(node, &ipv6_dirport);
return tor_addr_port_is_valid_ap(&ipv6_dirport, 0);
}
/** Return 1 if we prefer the IPv6 address and OR TCP port of
* <b>node</b>, else 0.
*
* We prefer the IPv6 address if the router has an IPv6 address,
* and we can use IPv6 addresses, and:
* i) the node_t says that it prefers IPv6
* or
* ii) the router has no IPv4 OR address.
*
* If you don't have a node, consider looking it up.
* If there is no node, use fascist_firewall_prefer_ipv6_orport().
*/
int
node_ipv6_or_preferred(const node_t *node)
{
const or_options_t *options = get_options();
tor_addr_port_t ipv4_addr;
node_assert_ok(node);
/* XX/teor - node->ipv6_preferred is set from
* fascist_firewall_prefer_ipv6_orport() each time the consensus is loaded.
*/
if (!fascist_firewall_use_ipv6(options)) {
return 0;
} else if (node->ipv6_preferred || node_get_prim_orport(node, &ipv4_addr)) {
return node_has_ipv6_orport(node);
}
return 0;
}
#define RETURN_IPV4_AP(r, port_field, ap_out) \
STMT_BEGIN \
if (r && tor_addr_port_is_valid_ipv4h((r)->addr, (r)->port_field, 0)) { \
tor_addr_from_ipv4h(&(ap_out)->addr, (r)->addr); \
(ap_out)->port = (r)->port_field; \
return 0; \
} \
STMT_END
/** Copy the primary (IPv4) OR port (IP address and TCP port) for
* <b>node</b> into *<b>ap_out</b>. Return 0 if a valid address and
* port was copied, else return non-zero.*/
int
node_get_prim_orport(const node_t *node, tor_addr_port_t *ap_out)
{
node_assert_ok(node);
tor_assert(ap_out);
RETURN_IPV4_AP(node->ri, or_port, ap_out);
RETURN_IPV4_AP(node->rs, or_port, ap_out);
/* Microdescriptors only have an IPv6 address */
return -1;
}
/** Copy the preferred OR port (IP address and TCP port) for
* <b>node</b> into *<b>ap_out</b>. */
void
node_get_pref_orport(const node_t *node, tor_addr_port_t *ap_out)
{
tor_assert(ap_out);
if (node_ipv6_or_preferred(node)) {
node_get_pref_ipv6_orport(node, ap_out);
} else {
/* the primary ORPort is always on IPv4 */
node_get_prim_orport(node, ap_out);
}
}
/** Copy the preferred IPv6 OR port (IP address and TCP port) for
* <b>node</b> into *<b>ap_out</b>. */
void
node_get_pref_ipv6_orport(const node_t *node, tor_addr_port_t *ap_out)
{
node_assert_ok(node);
tor_assert(ap_out);
/* Prefer routerstatus over microdesc for consistency with the
* fascist_firewall_* functions. Also check if the address or port are valid,
* and try another alternative if they are not. */
if (node->ri && tor_addr_port_is_valid(&node->ri->ipv6_addr,
node->ri->ipv6_orport, 0)) {
tor_addr_copy(&ap_out->addr, &node->ri->ipv6_addr);
ap_out->port = node->ri->ipv6_orport;
} else if (node->rs && tor_addr_port_is_valid(&node->rs->ipv6_addr,
node->rs->ipv6_orport, 0)) {
tor_addr_copy(&ap_out->addr, &node->rs->ipv6_addr);
ap_out->port = node->rs->ipv6_orport;
} else if (node->md && tor_addr_port_is_valid(&node->md->ipv6_addr,
node->md->ipv6_orport, 0)) {
tor_addr_copy(&ap_out->addr, &node->md->ipv6_addr);
ap_out->port = node->md->ipv6_orport;
} else {
tor_addr_make_null(&ap_out->addr, AF_INET6);
ap_out->port = 0;
}
}
/** Return 1 if we prefer the IPv6 address and Dir TCP port of
* <b>node</b>, else 0.
*
* We prefer the IPv6 address if the router has an IPv6 address,
* and we can use IPv6 addresses, and:
* i) the router has no IPv4 Dir address.
* or
* ii) our preference is for IPv6 Dir addresses.
*
* If there is no node, use fascist_firewall_prefer_ipv6_dirport().
*/
int
node_ipv6_dir_preferred(const node_t *node)
{
const or_options_t *options = get_options();
tor_addr_port_t ipv4_addr;
node_assert_ok(node);
/* node->ipv6_preferred is set from fascist_firewall_prefer_ipv6_orport(),
* so we can't use it to determine DirPort IPv6 preference.
* This means that bridge clients will use IPv4 DirPorts by default.
*/
if (!fascist_firewall_use_ipv6(options)) {
return 0;
} else if (node_get_prim_dirport(node, &ipv4_addr)
|| fascist_firewall_prefer_ipv6_dirport(get_options())) {
return node_has_ipv6_dirport(node);
}
return 0;
}
/** Copy the primary (IPv4) Dir port (IP address and TCP port) for
* <b>node</b> into *<b>ap_out</b>. Return 0 if a valid address and
* port was copied, else return non-zero.*/
int
node_get_prim_dirport(const node_t *node, tor_addr_port_t *ap_out)
{
node_assert_ok(node);
tor_assert(ap_out);
RETURN_IPV4_AP(node->ri, dir_port, ap_out);
RETURN_IPV4_AP(node->rs, dir_port, ap_out);
/* Microdescriptors only have an IPv6 address */
return -1;
}
#undef RETURN_IPV4_AP
/** Copy the preferred Dir port (IP address and TCP port) for
* <b>node</b> into *<b>ap_out</b>. */
void
node_get_pref_dirport(const node_t *node, tor_addr_port_t *ap_out)
{
tor_assert(ap_out);
if (node_ipv6_dir_preferred(node)) {
node_get_pref_ipv6_dirport(node, ap_out);
} else {
/* the primary DirPort is always on IPv4 */
node_get_prim_dirport(node, ap_out);
}
}
/** Copy the preferred IPv6 Dir port (IP address and TCP port) for
* <b>node</b> into *<b>ap_out</b>. */
void
node_get_pref_ipv6_dirport(const node_t *node, tor_addr_port_t *ap_out)
{
node_assert_ok(node);
tor_assert(ap_out);
/* Check if the address or port are valid, and try another alternative if
* they are not. Note that microdescriptors have no dir_port. */
/* Assume IPv4 and IPv6 dirports are the same */
if (node->ri && tor_addr_port_is_valid(&node->ri->ipv6_addr,
node->ri->dir_port, 0)) {
tor_addr_copy(&ap_out->addr, &node->ri->ipv6_addr);
ap_out->port = node->ri->dir_port;
} else if (node->rs && tor_addr_port_is_valid(&node->rs->ipv6_addr,
node->rs->dir_port, 0)) {
tor_addr_copy(&ap_out->addr, &node->rs->ipv6_addr);
ap_out->port = node->rs->dir_port;
} else {
tor_addr_make_null(&ap_out->addr, AF_INET6);
ap_out->port = 0;
}
}
/** Return true iff <b>md</b> has a curve25519 onion key.
* Use node_has_curve25519_onion_key() instead of calling this directly. */
static int
microdesc_has_curve25519_onion_key(const microdesc_t *md)
{
if (!md) {
return 0;
}
if (!md->onion_curve25519_pkey) {
return 0;
}
if (tor_mem_is_zero((const char*)md->onion_curve25519_pkey->public_key,
CURVE25519_PUBKEY_LEN)) {
return 0;
}
return 1;
}
/** Return true iff <b>node</b> has a curve25519 onion key. */
int
node_has_curve25519_onion_key(const node_t *node)
{
if (!node)
return 0;
if (node->ri)
return routerinfo_has_curve25519_onion_key(node->ri);
else if (node->md)
return microdesc_has_curve25519_onion_key(node->md);
else
return 0;
}
/** Refresh the country code of <b>ri</b>. This function MUST be called on
* each router when the GeoIP database is reloaded, and on all new routers. */
void
node_set_country(node_t *node)
{
tor_addr_t addr = TOR_ADDR_NULL;
/* XXXXipv6 */
if (node->rs)
tor_addr_from_ipv4h(&addr, node->rs->addr);
else if (node->ri)
tor_addr_from_ipv4h(&addr, node->ri->addr);
node->country = geoip_get_country_by_addr(&addr);
}
/** Set the country code of all routers in the routerlist. */
void
nodelist_refresh_countries(void)
{
smartlist_t *nodes = nodelist_get_list();
SMARTLIST_FOREACH(nodes, node_t *, node,
node_set_country(node));
}
/** Return true iff router1 and router2 have similar enough network addresses
* that we should treat them as being in the same family */
static inline int
addrs_in_same_network_family(const tor_addr_t *a1,
const tor_addr_t *a2)
{
return 0 == tor_addr_compare_masked(a1, a2, 16, CMP_SEMANTIC);
}
/** Return true if <b>node</b>'s nickname matches <b>nickname</b>
* (case-insensitive), or if <b>node's</b> identity key digest
* matches a hexadecimal value stored in <b>nickname</b>. Return
* false otherwise. */
static int
node_nickname_matches(const node_t *node, const char *nickname)
{
const char *n = node_get_nickname(node);
if (n && nickname[0]!='$' && !strcasecmp(n, nickname))
return 1;
return hex_digest_nickname_matches(nickname,
node->identity,
n,
node_is_named(node));
}
/** Return true iff <b>node</b> is named by some nickname in <b>lst</b>. */
static inline int
node_in_nickname_smartlist(const smartlist_t *lst, const node_t *node)
{
if (!lst) return 0;
SMARTLIST_FOREACH(lst, const char *, name, {
if (node_nickname_matches(node, name))
return 1;
});
return 0;
}
/** Return true iff r1 and r2 are in the same family, but not the same
* router. */
int
nodes_in_same_family(const node_t *node1, const node_t *node2)
{
const or_options_t *options = get_options();
/* Are they in the same family because of their addresses? */
if (options->EnforceDistinctSubnets) {
tor_addr_t a1, a2;
node_get_addr(node1, &a1);
node_get_addr(node2, &a2);
if (addrs_in_same_network_family(&a1, &a2))
return 1;
}
/* Are they in the same family because the agree they are? */
{
const smartlist_t *f1, *f2;
f1 = node_get_declared_family(node1);
f2 = node_get_declared_family(node2);
if (f1 && f2 &&
node_in_nickname_smartlist(f1, node2) &&
node_in_nickname_smartlist(f2, node1))
return 1;
}
/* Are they in the same option because the user says they are? */
if (options->NodeFamilySets) {
SMARTLIST_FOREACH(options->NodeFamilySets, const routerset_t *, rs, {
if (routerset_contains_node(rs, node1) &&
routerset_contains_node(rs, node2))
return 1;
});
}
return 0;
}
/**
* Add all the family of <b>node</b>, including <b>node</b> itself, to
* the smartlist <b>sl</b>.
*
* This is used to make sure we don't pick siblings in a single path, or
* pick more than one relay from a family for our entry guard list.
* Note that a node may be added to <b>sl</b> more than once if it is
* part of <b>node</b>'s family for more than one reason.
*/
void
nodelist_add_node_and_family(smartlist_t *sl, const node_t *node)
{
const smartlist_t *all_nodes = nodelist_get_list();
const smartlist_t *declared_family;
const or_options_t *options = get_options();
tor_assert(node);
declared_family = node_get_declared_family(node);
/* Let's make sure that we have the node itself, if it's a real node. */
{
const node_t *real_node = node_get_by_id(node->identity);
if (real_node)
smartlist_add(sl, (node_t*)real_node);
}
/* First, add any nodes with similar network addresses. */
if (options->EnforceDistinctSubnets) {
tor_addr_t node_addr;
node_get_addr(node, &node_addr);
SMARTLIST_FOREACH_BEGIN(all_nodes, const node_t *, node2) {
tor_addr_t a;
node_get_addr(node2, &a);
if (addrs_in_same_network_family(&a, &node_addr))
smartlist_add(sl, (void*)node2);
} SMARTLIST_FOREACH_END(node2);
}
/* Now, add all nodes in the declared_family of this node, if they
* also declare this node to be in their family. */
if (declared_family) {
/* Add every r such that router declares familyness with node, and node
* declares familyhood with router. */
SMARTLIST_FOREACH_BEGIN(declared_family, const char *, name) {
const node_t *node2;
const smartlist_t *family2;
if (!(node2 = node_get_by_nickname(name, 0)))
continue;
if (!(family2 = node_get_declared_family(node2)))
continue;
SMARTLIST_FOREACH_BEGIN(family2, const char *, name2) {
if (node_nickname_matches(node, name2)) {
smartlist_add(sl, (void*)node2);
break;
}
} SMARTLIST_FOREACH_END(name2);
} SMARTLIST_FOREACH_END(name);
}
/* If the user declared any families locally, honor those too. */
if (options->NodeFamilySets) {
SMARTLIST_FOREACH(options->NodeFamilySets, const routerset_t *, rs, {
if (routerset_contains_node(rs, node)) {
routerset_get_all_nodes(sl, rs, NULL, 0);
}
});
}
}
/** Find a router that's up, that has this IP address, and
* that allows exit to this address:port, or return NULL if there
* isn't a good one.
* Don't exit enclave to excluded relays -- it wouldn't actually
* hurt anything, but this way there are fewer confused users.
*/
const node_t *
router_find_exact_exit_enclave(const char *address, uint16_t port)
{/*XXXX MOVE*/
uint32_t addr;
struct in_addr in;
tor_addr_t a;
const or_options_t *options = get_options();
if (!tor_inet_aton(address, &in))
return NULL; /* it's not an IP already */
addr = ntohl(in.s_addr);
tor_addr_from_ipv4h(&a, addr);
SMARTLIST_FOREACH(nodelist_get_list(), const node_t *, node, {
if (node_get_addr_ipv4h(node) == addr &&
node->is_running &&
compare_tor_addr_to_node_policy(&a, port, node) ==
ADDR_POLICY_ACCEPTED &&
!routerset_contains_node(options->ExcludeExitNodesUnion_, node))
return node;
});
return NULL;
}
/** Return 1 if <b>router</b> is not suitable for these parameters, else 0.
* If <b>need_uptime</b> is non-zero, we require a minimum uptime.
* If <b>need_capacity</b> is non-zero, we require a minimum advertised
* bandwidth.
* If <b>need_guard</b>, we require that the router is a possible entry guard.
*/
int
node_is_unreliable(const node_t *node, int need_uptime,
int need_capacity, int need_guard)
{
if (need_uptime && !node->is_stable)
return 1;
if (need_capacity && !node->is_fast)
return 1;
if (need_guard && !node->is_possible_guard)
return 1;
return 0;
}
/** Return 1 if all running sufficiently-stable routers we can use will reject
* addr:port. Return 0 if any might accept it. */
int
router_exit_policy_all_nodes_reject(const tor_addr_t *addr, uint16_t port,
int need_uptime)
{
addr_policy_result_t r;
SMARTLIST_FOREACH_BEGIN(nodelist_get_list(), const node_t *, node) {
if (node->is_running &&
!node_is_unreliable(node, need_uptime, 0, 0)) {
r = compare_tor_addr_to_node_policy(addr, port, node);
if (r != ADDR_POLICY_REJECTED && r != ADDR_POLICY_PROBABLY_REJECTED)
return 0; /* this one could be ok. good enough. */
}
} SMARTLIST_FOREACH_END(node);
return 1; /* all will reject. */
}
/** Mark the router with ID <b>digest</b> as running or non-running
* in our routerlist. */
void
router_set_status(const char *digest, int up)
{
node_t *node;
tor_assert(digest);
SMARTLIST_FOREACH(router_get_fallback_dir_servers(),
dir_server_t *, d,
if (tor_memeq(d->digest, digest, DIGEST_LEN))
d->is_running = up);
SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
dir_server_t *, d,
if (tor_memeq(d->digest, digest, DIGEST_LEN))
d->is_running = up);
node = node_get_mutable_by_id(digest);
if (node) {
#if 0
log_debug(LD_DIR,"Marking router %s as %s.",
node_describe(node), up ? "up" : "down");
#endif
if (!up && node_is_me(node) && !net_is_disabled())
log_warn(LD_NET, "We just marked ourself as down. Are your external "
"addresses reachable?");
if (bool_neq(node->is_running, up))
router_dir_info_changed();
node->is_running = up;
}
}
/** True iff, the last time we checked whether we had enough directory info
* to build circuits, the answer was "yes". If there are no exits in the
* consensus, we act as if we have 100% of the exit directory info. */
static int have_min_dir_info = 0;
/** Does the consensus contain nodes that can exit? */
static consensus_path_type_t have_consensus_path = CONSENSUS_PATH_UNKNOWN;
/** True iff enough has changed since the last time we checked whether we had
* enough directory info to build circuits that our old answer can no longer
* be trusted. */
static int need_to_update_have_min_dir_info = 1;
/** String describing what we're missing before we have enough directory
* info. */
static char dir_info_status[512] = "";
/** Return true iff we have enough consensus information to
* start building circuits. Right now, this means "a consensus that's
* less than a day old, and at least 60% of router descriptors (configurable),
* weighted by bandwidth. Treat the exit fraction as 100% if there are
* no exits in the consensus."
* To obtain the final weighted bandwidth, we multiply the
* weighted bandwidth fraction for each position (guard, middle, exit). */
int
router_have_minimum_dir_info(void)
{
static int logged_delay=0;
const char *delay_fetches_msg = NULL;
if (should_delay_dir_fetches(get_options(), &delay_fetches_msg)) {
if (!logged_delay)
log_notice(LD_DIR, "Delaying directory fetches: %s", delay_fetches_msg);
logged_delay=1;
strlcpy(dir_info_status, delay_fetches_msg, sizeof(dir_info_status));
return 0;
}
logged_delay = 0; /* reset it if we get this far */
if (PREDICT_UNLIKELY(need_to_update_have_min_dir_info)) {
update_router_have_minimum_dir_info();
}
return have_min_dir_info;
}
/** Set to CONSENSUS_PATH_EXIT if there is at least one exit node
* in the consensus. We update this flag in compute_frac_paths_available if
* there is at least one relay that has an Exit flag in the consensus.
* Used to avoid building exit circuits when they will almost certainly fail.
* Set to CONSENSUS_PATH_INTERNAL if there are no exits in the consensus.
* (This situation typically occurs during bootstrap of a test network.)
* Set to CONSENSUS_PATH_UNKNOWN if we have never checked, or have
* reason to believe our last known value was invalid or has expired.
* If we're in a network with TestingDirAuthVoteExit set,
* this can cause router_have_consensus_path() to be set to
* CONSENSUS_PATH_EXIT, even if there are no nodes with accept exit policies.
*/
consensus_path_type_t
router_have_consensus_path(void)
{
return have_consensus_path;
}
/** Called when our internal view of the directory has changed. This can be
* when the authorities change, networkstatuses change, the list of routerdescs
* changes, or number of running routers changes.
*/
void
router_dir_info_changed(void)
{
need_to_update_have_min_dir_info = 1;
rend_hsdir_routers_changed();
}
/** Return a string describing what we're missing before we have enough
* directory info. */
const char *
get_dir_info_status_string(void)
{
return dir_info_status;
}
/** Iterate over the servers listed in <b>consensus</b>, and count how many of
* them seem like ones we'd use (store this in *<b>num_usable</b>), and how
* many of <em>those</em> we have descriptors for (store this in
* *<b>num_present</b>).
*
* If <b>in_set</b> is non-NULL, only consider those routers in <b>in_set</b>.
* If <b>exit_only</b> is USABLE_DESCRIPTOR_EXIT_ONLY, only consider nodes
* with the Exit flag.
* If *<b>descs_out</b> is present, add a node_t for each usable descriptor
* to it.
*/
static void
count_usable_descriptors(int *num_present, int *num_usable,
smartlist_t *descs_out,
const networkstatus_t *consensus,
const or_options_t *options, time_t now,
routerset_t *in_set,
usable_descriptor_t exit_only)
{
const int md = (consensus->flavor == FLAV_MICRODESC);
*num_present = 0, *num_usable = 0;
SMARTLIST_FOREACH_BEGIN(consensus->routerstatus_list, routerstatus_t *, rs)
{
const node_t *node = node_get_by_id(rs->identity_digest);
if (!node)
continue; /* This would be a bug: every entry in the consensus is
* supposed to have a node. */
if (exit_only == USABLE_DESCRIPTOR_EXIT_ONLY && ! rs->is_exit)
continue;
if (in_set && ! routerset_contains_routerstatus(in_set, rs, -1))
continue;
if (client_would_use_router(rs, now, options)) {
const char * const digest = rs->descriptor_digest;
int present;
++*num_usable; /* the consensus says we want it. */
if (md)
present = NULL != microdesc_cache_lookup_by_digest256(NULL, digest);
else
present = NULL != router_get_by_descriptor_digest(digest);
if (present) {
/* we have the descriptor listed in the consensus. */
++*num_present;
}
if (descs_out)
smartlist_add(descs_out, (node_t*)node);
}
}
SMARTLIST_FOREACH_END(rs);
log_debug(LD_DIR, "%d usable, %d present (%s%s).",
*num_usable, *num_present,
md ? "microdesc" : "desc",
exit_only == USABLE_DESCRIPTOR_EXIT_ONLY ? " exits" : "s");
}
/** Return an estimate of which fraction of usable paths through the Tor
* network we have available for use. Count how many routers seem like ones
* we'd use (store this in *<b>num_usable_out</b>), and how many of
* <em>those</em> we have descriptors for (store this in
* *<b>num_present_out</b>.)
*
* If **<b>status_out</b> is present, allocate a new string and print the
* available percentages of guard, middle, and exit nodes to it, noting
* whether there are exits in the consensus.
* If there are no guards in the consensus,
* we treat the exit fraction as 100%.
*/
static double
compute_frac_paths_available(const networkstatus_t *consensus,
const or_options_t *options, time_t now,
int *num_present_out, int *num_usable_out,
char **status_out)
{
smartlist_t *guards = smartlist_new();
smartlist_t *mid = smartlist_new();
smartlist_t *exits = smartlist_new();
double f_guard, f_mid, f_exit;
double f_path = 0.0;
/* Used to determine whether there are any exits in the consensus */
int np = 0;
/* Used to determine whether there are any exits with descriptors */
int nu = 0;
const int authdir = authdir_mode_v3(options);
count_usable_descriptors(num_present_out, num_usable_out,
mid, consensus, options, now, NULL,
USABLE_DESCRIPTOR_ALL);
if (options->EntryNodes) {
count_usable_descriptors(&np, &nu, guards, consensus, options, now,
options->EntryNodes, USABLE_DESCRIPTOR_ALL);
} else {
SMARTLIST_FOREACH(mid, const node_t *, node, {
if (authdir) {
if (node->rs && node->rs->is_possible_guard)
smartlist_add(guards, (node_t*)node);
} else {
if (node->is_possible_guard)
smartlist_add(guards, (node_t*)node);
}
});
}
/* All nodes with exit flag
* If we're in a network with TestingDirAuthVoteExit set,
* this can cause false positives on have_consensus_path,
* incorrectly setting it to CONSENSUS_PATH_EXIT. This is
* an unavoidable feature of forcing authorities to declare
* certain nodes as exits.
*/
count_usable_descriptors(&np, &nu, exits, consensus, options, now,
NULL, USABLE_DESCRIPTOR_EXIT_ONLY);
log_debug(LD_NET,
"%s: %d present, %d usable",
"exits",
np,
nu);
/* We need at least 1 exit present in the consensus to consider
* building exit paths */
/* Update our understanding of whether the consensus has exits */
consensus_path_type_t old_have_consensus_path = have_consensus_path;
have_consensus_path = ((nu > 0) ?
CONSENSUS_PATH_EXIT :
CONSENSUS_PATH_INTERNAL);
if (have_consensus_path == CONSENSUS_PATH_INTERNAL
&& old_have_consensus_path != have_consensus_path) {
log_notice(LD_NET,
"The current consensus has no exit nodes. "
"Tor can only build internal paths, "
"such as paths to hidden services.");
/* However, exit nodes can reachability self-test using this consensus,
* join the network, and appear in a later consensus. This will allow
* the network to build exit paths, such as paths for world wide web
* browsing (as distinct from hidden service web browsing). */
}
f_guard = frac_nodes_with_descriptors(guards, WEIGHT_FOR_GUARD);
f_mid = frac_nodes_with_descriptors(mid, WEIGHT_FOR_MID);
f_exit = frac_nodes_with_descriptors(exits, WEIGHT_FOR_EXIT);
log_debug(LD_NET,
"f_guard: %.2f, f_mid: %.2f, f_exit: %.2f",
f_guard,
f_mid,
f_exit);
smartlist_free(guards);
smartlist_free(mid);
smartlist_free(exits);
if (options->ExitNodes) {
double f_myexit, f_myexit_unflagged;
smartlist_t *myexits= smartlist_new();
smartlist_t *myexits_unflagged = smartlist_new();
/* All nodes with exit flag in ExitNodes option */
count_usable_descriptors(&np, &nu, myexits, consensus, options, now,
options->ExitNodes, USABLE_DESCRIPTOR_EXIT_ONLY);
log_debug(LD_NET,
"%s: %d present, %d usable",
"myexits",
np,
nu);
/* Now compute the nodes in the ExitNodes option where which we don't know
* what their exit policy is, or we know it permits something. */
count_usable_descriptors(&np, &nu, myexits_unflagged,
consensus, options, now,
options->ExitNodes, USABLE_DESCRIPTOR_ALL);
log_debug(LD_NET,
"%s: %d present, %d usable",
"myexits_unflagged (initial)",
np,
nu);
SMARTLIST_FOREACH_BEGIN(myexits_unflagged, const node_t *, node) {
if (node_has_descriptor(node) && node_exit_policy_rejects_all(node)) {
SMARTLIST_DEL_CURRENT(myexits_unflagged, node);
/* this node is not actually an exit */
np--;
/* this node is unusable as an exit */
nu--;
}
} SMARTLIST_FOREACH_END(node);
log_debug(LD_NET,
"%s: %d present, %d usable",
"myexits_unflagged (final)",
np,
nu);
f_myexit= frac_nodes_with_descriptors(myexits,WEIGHT_FOR_EXIT);
f_myexit_unflagged=
frac_nodes_with_descriptors(myexits_unflagged,WEIGHT_FOR_EXIT);
log_debug(LD_NET,
"f_exit: %.2f, f_myexit: %.2f, f_myexit_unflagged: %.2f",
f_exit,
f_myexit,
f_myexit_unflagged);
/* If our ExitNodes list has eliminated every possible Exit node, and there
* were some possible Exit nodes, then instead consider nodes that permit
* exiting to some ports. */
if (smartlist_len(myexits) == 0 &&
smartlist_len(myexits_unflagged)) {
f_myexit = f_myexit_unflagged;
}
smartlist_free(myexits);
smartlist_free(myexits_unflagged);
/* This is a tricky point here: we don't want to make it easy for a
* directory to trickle exits to us until it learns which exits we have
* configured, so require that we have a threshold both of total exits
* and usable exits. */
if (f_myexit < f_exit)
f_exit = f_myexit;
}
/* if the consensus has no exits, treat the exit fraction as 100% */
if (router_have_consensus_path() != CONSENSUS_PATH_EXIT) {
f_exit = 1.0;
}
f_path = f_guard * f_mid * f_exit;
if (status_out)
tor_asprintf(status_out,
"%d%% of guards bw, "
"%d%% of midpoint bw, and "
"%d%% of exit bw%s = "
"%d%% of path bw",
(int)(f_guard*100),
(int)(f_mid*100),
(int)(f_exit*100),
(router_have_consensus_path() == CONSENSUS_PATH_EXIT ?
"" :
" (no exits in consensus)"),
(int)(f_path*100));
return f_path;
}
/** We just fetched a new set of descriptors. Compute how far through
* the "loading descriptors" bootstrapping phase we are, so we can inform
* the controller of our progress. */
int
count_loading_descriptors_progress(void)
{
int num_present = 0, num_usable=0;
time_t now = time(NULL);
const or_options_t *options = get_options();
const networkstatus_t *consensus =
networkstatus_get_reasonably_live_consensus(now,usable_consensus_flavor());
double paths, fraction;
if (!consensus)
return 0; /* can't count descriptors if we have no list of them */
paths = compute_frac_paths_available(consensus, options, now,
&num_present, &num_usable,
NULL);
fraction = paths / get_frac_paths_needed_for_circs(options,consensus);
if (fraction > 1.0)
return 0; /* it's not the number of descriptors holding us back */
return BOOTSTRAP_STATUS_LOADING_DESCRIPTORS + (int)
(fraction*(BOOTSTRAP_STATUS_CONN_OR-1 -
BOOTSTRAP_STATUS_LOADING_DESCRIPTORS));
}
/** Return the fraction of paths needed before we're willing to build
* circuits, as configured in <b>options</b>, or in the consensus <b>ns</b>. */
static double
get_frac_paths_needed_for_circs(const or_options_t *options,
const networkstatus_t *ns)
{
#define DFLT_PCT_USABLE_NEEDED 60
if (options->PathsNeededToBuildCircuits >= 0.0) {
return options->PathsNeededToBuildCircuits;
} else {
return networkstatus_get_param(ns, "min_paths_for_circs_pct",
DFLT_PCT_USABLE_NEEDED,
25, 95)/100.0;
}
}
/** Change the value of have_min_dir_info, setting it true iff we have enough
* network and router information to build circuits. Clear the value of
* need_to_update_have_min_dir_info. */
static void
update_router_have_minimum_dir_info(void)
{
time_t now = time(NULL);
int res;
const or_options_t *options = get_options();
const networkstatus_t *consensus =
networkstatus_get_reasonably_live_consensus(now,usable_consensus_flavor());
int using_md;
if (!consensus) {
if (!networkstatus_get_latest_consensus())
strlcpy(dir_info_status, "We have no usable consensus.",
sizeof(dir_info_status));
else
strlcpy(dir_info_status, "We have no recent usable consensus.",
sizeof(dir_info_status));
res = 0;
goto done;
}
using_md = consensus->flavor == FLAV_MICRODESC;
/* Check fraction of available paths */
{
char *status = NULL;
int num_present=0, num_usable=0;
double paths = compute_frac_paths_available(consensus, options, now,
&num_present, &num_usable,
&status);
if (paths < get_frac_paths_needed_for_circs(options,consensus)) {
tor_snprintf(dir_info_status, sizeof(dir_info_status),
"We need more %sdescriptors: we have %d/%d, and "
"can only build %d%% of likely paths. (We have %s.)",
using_md?"micro":"", num_present, num_usable,
(int)(paths*100), status);
tor_free(status);
res = 0;
control_event_bootstrap(BOOTSTRAP_STATUS_REQUESTING_DESCRIPTORS, 0);
goto done;
}
tor_free(status);
res = 1;
}
done:
/* If paths have just become available in this update. */
if (res && !have_min_dir_info) {
control_event_client_status(LOG_NOTICE, "ENOUGH_DIR_INFO");
if (control_event_bootstrap(BOOTSTRAP_STATUS_CONN_OR, 0) == 0) {
log_notice(LD_DIR,
"We now have enough directory information to build circuits.");
}
}
/* If paths have just become unavailable in this update. */
if (!res && have_min_dir_info) {
int quiet = directory_too_idle_to_fetch_descriptors(options, now);
tor_log(quiet ? LOG_INFO : LOG_NOTICE, LD_DIR,
"Our directory information is no longer up-to-date "
"enough to build circuits: %s", dir_info_status);
/* a) make us log when we next complete a circuit, so we know when Tor
* is back up and usable, and b) disable some activities that Tor
* should only do while circuits are working, like reachability tests
* and fetching bridge descriptors only over circuits. */
note_that_we_maybe_cant_complete_circuits();
have_consensus_path = CONSENSUS_PATH_UNKNOWN;
control_event_client_status(LOG_NOTICE, "NOT_ENOUGH_DIR_INFO");
}
have_min_dir_info = res;
need_to_update_have_min_dir_info = 0;
}
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