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d273891107
tor/src/or/routerlist.c
Roger Dingledine d273891107 if we fetch the dir from a mirror that has a wildly skewed 
clock, then don't bother checking recommended-versions: it will
just make us sad.

as a side effect, people running obsolete versions and whose
clocks are wildly skewed will not be auto-shut-down. but they
will still get warns about their clock skew.


svn:r3459
2005-01-29 11:48:37 +00:00

1327 lines
42 KiB
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/* Copyright 2001 Matej Pfajfar.
* Copyright 2001-2004 Roger Dingledine.
* Copyright 2004 Roger Dingledine, Nick Mathewson. */
/* See LICENSE for licensing information */
/* $Id$ */
const char routerlist_c_id[] = "$Id$";
#include "or.h"
/**
* \file routerlist.c
*
* \brief Code to
* maintain and access the global list of routerinfos for known
* servers.
**/
/****************************************************************************/
static smartlist_t *trusted_dir_servers = NULL;
/* static function prototypes */
static routerinfo_t *
router_pick_directory_server_impl(int requireothers, int fascistfirewall,
int for_runningrouters);
static trusted_dir_server_t *
router_pick_trusteddirserver_impl(int requireother, int fascistfirewall);
static void mark_all_trusteddirservers_up(void);
static int router_resolve_routerlist(routerlist_t *dir);
/****************************************************************************/
/****
* Functions to manage and access our list of known routers. (Note:
* dirservers maintain a separate, independent list of known router
* descriptors.)
*****/
/** Global list of all of the routers that we, as an OR or OP, know about. */
static routerlist_t *routerlist = NULL;
extern int has_fetched_directory; /**< from main.c */
/**
* Reload the original list of trusted dirservers, and the most recent
* cached directory (if present).
*/
int router_reload_router_list(void)
{
char filename[512];
int is_recent;
struct stat st;
char *s;
tor_assert(get_options()->DataDirectory);
tor_snprintf(filename,sizeof(filename),"%s/cached-directory",
get_options()->DataDirectory);
s = read_file_to_str(filename,0);
if (s) {
stat(filename, &st); /* if s is true, stat probably worked */
log_fn(LOG_INFO, "Loading cached directory from %s", filename);
is_recent = st.st_mtime > time(NULL) - 60*15;
if (router_load_routerlist_from_directory(s, NULL, is_recent, 1) < 0) {
log_fn(LOG_WARN, "Cached directory at '%s' was unparseable; ignoring.", filename);
}
if (routerlist &&
((routerlist->published_on > time(NULL) - MIN_ONION_KEY_LIFETIME/2)
|| is_recent)) {
directory_has_arrived(st.st_mtime); /* do things we've been waiting to do */
}
tor_free(s);
}
return 0;
}
/* Set *<b>outp</b> to a smartlist containing a list of
* trusted_dir_server_t * for all known trusted dirservers. Callers
* must not modify the list or its contents.
*/
void router_get_trusted_dir_servers(smartlist_t **outp)
{
if (!trusted_dir_servers)
trusted_dir_servers = smartlist_create();
*outp = trusted_dir_servers;
}
/** Try to find a running dirserver. If there are no running dirservers
* in our routerlist, set all the authoritative ones as running again,
* and pick one. If there are no dirservers at all in our routerlist,
* reload the routerlist and try one last time. If for_runningrouters is
* true, then only pick a dirserver that can answer runningrouters queries
* (that is, a trusted dirserver, or one running 0.0.9rc5-cvs or later).
*/
routerinfo_t *router_pick_directory_server(int requireothers,
int fascistfirewall,
int for_runningrouters,
int retry_if_no_servers) {
routerinfo_t *choice;
if (!routerlist)
return NULL;
choice = router_pick_directory_server_impl(requireothers, fascistfirewall,
for_runningrouters);
if (choice || !retry_if_no_servers)
return choice;
log_fn(LOG_INFO,"No reachable router entries for dirservers. Trying them all again.");
/* mark all authdirservers as up again */
mark_all_trusteddirservers_up();
/* try again */
choice = router_pick_directory_server_impl(requireothers, fascistfirewall,
for_runningrouters);
if (choice)
return choice;
log_fn(LOG_INFO,"Still no %s router entries. Reloading and trying again.",
get_options()->FascistFirewall ? "reachable" : "known");
has_fetched_directory=0; /* reset it */
if (router_reload_router_list()) {
return NULL;
}
/* give it one last try */
choice = router_pick_directory_server_impl(requireothers, 0,
for_runningrouters);
return choice;
}
trusted_dir_server_t *router_pick_trusteddirserver(int requireothers,
int fascistfirewall,
int retry_if_no_servers) {
trusted_dir_server_t *choice;
choice = router_pick_trusteddirserver_impl(requireothers, fascistfirewall);
if (choice || !retry_if_no_servers)
return choice;
log_fn(LOG_INFO,"No trusted dirservers are reachable. Trying them all again.");
/* mark all authdirservers as up again */
mark_all_trusteddirservers_up();
/* try again */
choice = router_pick_trusteddirserver_impl(requireothers, fascistfirewall);
if (choice)
return choice;
log_fn(LOG_WARN,"Still no dirservers %s. Reloading and trying again.",
get_options()->FascistFirewall ? "reachable" : "known");
has_fetched_directory=0; /* reset it */
if (router_reload_router_list()) {
return NULL;
}
/* give it one last try */
choice = router_pick_trusteddirserver_impl(requireothers, 0);
return choice;
}
/** Pick a random running router from our routerlist. If requireauth,
* it has to be a trusted server. If requireothers, it cannot be us.
*/
static routerinfo_t *
router_pick_directory_server_impl(int requireothers, int fascistfirewall,
int for_runningrouters)
{
int i;
routerinfo_t *router;
smartlist_t *sl;
if (!routerlist)
return NULL;
if (get_options()->HttpProxy)
fascistfirewall = 0;
/* Find all the running dirservers we know about. */
sl = smartlist_create();
for (i=0;i< smartlist_len(routerlist->routers); i++) {
router = smartlist_get(routerlist->routers, i);
if (!router->is_running || !router->dir_port)
continue;
if (requireothers && router_is_me(router))
continue;
if (fascistfirewall) {
if (!smartlist_string_num_isin(get_options()->FirewallPorts, router->dir_port))
continue;
}
/* before 0.0.9rc5-cvs, only trusted dirservers served status info. */
if (for_runningrouters &&
!(tor_version_as_new_as(router->platform,"0.0.9rc5-cvs") ||
router_digest_is_trusted_dir(router->identity_digest)))
continue;
smartlist_add(sl, router);
}
router = smartlist_choose(sl);
smartlist_free(sl);
return router;
}
static trusted_dir_server_t *
router_pick_trusteddirserver_impl(int requireother, int fascistfirewall)
{
smartlist_t *sl;
routerinfo_t *me;
trusted_dir_server_t *ds;
sl = smartlist_create();
me = router_get_my_routerinfo();
if (!trusted_dir_servers)
return NULL;
if (get_options()->HttpProxy)
fascistfirewall = 0;
SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, d,
{
if (!d->is_running) continue;
if (requireother && me &&
!memcmp(me->identity_digest, d->digest, DIGEST_LEN))
continue;
if (fascistfirewall) {
if (!smartlist_string_num_isin(get_options()->FirewallPorts, d->dir_port))
continue;
}
smartlist_add(sl, d);
});
ds = smartlist_choose(sl);
smartlist_free(sl);
return ds;
}
/** Go through and mark the auth dirservers as up */
static void mark_all_trusteddirservers_up(void) {
if (routerlist) {
SMARTLIST_FOREACH(routerlist->routers, routerinfo_t *, router,
if (router_digest_is_trusted_dir(router->identity_digest)) {
tor_assert(router->dir_port > 0);
router->is_running = 1;
router->status_set_at = time(NULL);
});
}
if (trusted_dir_servers) {
SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, dir,
dir->is_running = 1);
}
}
/** Return 0 if \exists an authoritative dirserver that's currently
* thought to be running, else return 1.
*/
int all_trusted_directory_servers_down(void) {
if (!trusted_dir_servers)
return 1;
SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, dir,
if (dir->is_running) return 0);
return 1;
}
/** Add all the family of <b>router</b> to the smartlist <b>sl</b>.
*/
void routerlist_add_family(smartlist_t *sl, routerinfo_t *router) {
routerinfo_t *r;
struct config_line_t *cl;
if (!router->declared_family)
return;
/* Add every r such that router declares familyness with r, and r
* declares familyhood with router. */
SMARTLIST_FOREACH(router->declared_family, const char *, n,
{
if (!(r = router_get_by_nickname(n)))
continue;
if (!r->declared_family)
continue;
SMARTLIST_FOREACH(r->declared_family, const char *, n2,
{
if (router_nickname_matches(router, n2))
smartlist_add(sl, r);
});
});
for (cl = get_options()->NodeFamilies; cl; cl = cl->next) {
if (router_nickname_is_in_list(router, cl->value)) {
add_nickname_list_to_smartlist(sl, cl->value, 0);
}
}
}
/** Given a comma-and-whitespace separated list of nicknames, see which
* nicknames in <b>list</b> name routers in our routerlist that are
* currently running. Add the routerinfos for those routers to <b>sl</b>.
*/
void
add_nickname_list_to_smartlist(smartlist_t *sl, const char *list, int warn_if_down)
{
routerinfo_t *router;
smartlist_t *nickname_list;
if (!list)
return; /* nothing to do */
tor_assert(sl);
nickname_list = smartlist_create();
smartlist_split_string(nickname_list, list, ",",
SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
SMARTLIST_FOREACH(nickname_list, const char *, nick, {
if (!is_legal_nickname_or_hexdigest(nick)) {
log_fn(LOG_WARN,"Nickname %s is misformed; skipping", nick);
continue;
}
router = router_get_by_nickname(nick);
if (router) {
if (router->is_running)
smartlist_add(sl,router);
else
log_fn(warn_if_down ? LOG_WARN : LOG_DEBUG,
"Nickname list includes '%s' which is known but down.",nick);
} else
log_fn(has_fetched_directory ? LOG_WARN : LOG_INFO,
"Nickname list includes '%s' which isn't a known router.",nick);
});
SMARTLIST_FOREACH(nickname_list, char *, nick, tor_free(nick));
smartlist_free(nickname_list);
}
/** Return 1 iff any member of the comma-separated list <b>list</b> is an
* acceptable nickname or hexdigest for <b>router</b>. Else return 0.
*/
int
router_nickname_is_in_list(routerinfo_t *router, const char *list)
{
smartlist_t *nickname_list;
int v = 0;
if (!list)
return 0; /* definitely not */
tor_assert(router);
nickname_list = smartlist_create();
smartlist_split_string(nickname_list, list, ",",
SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
SMARTLIST_FOREACH(nickname_list, const char *, cp,
if (router_nickname_matches(router, cp)) {v=1;break;});
SMARTLIST_FOREACH(nickname_list, char *, cp, tor_free(cp));
smartlist_free(nickname_list);
return v;
}
/** Add every router from our routerlist that is currently running to
* <b>sl</b>.
*/
static void
router_add_running_routers_to_smartlist(smartlist_t *sl, int allow_unverified,
int need_uptime, int need_capacity)
{
routerinfo_t *router;
int i;
if (!routerlist)
return;
for (i=0;i<smartlist_len(routerlist->routers);i++) {
router = smartlist_get(routerlist->routers, i);
if (router->is_running &&
(router->is_verified ||
(allow_unverified &&
!router_is_unreliable(router, need_uptime, need_capacity)))) {
/* If it's running, and either it's verified or we're ok picking
* unverified routers and this one is suitable.
*/
smartlist_add(sl, router);
}
}
}
routerinfo_t *
routerlist_find_my_routerinfo(void) {
routerinfo_t *router;
int i;
if (!routerlist)
return NULL;
for (i=0;i<smartlist_len(routerlist->routers);i++) {
router = smartlist_get(routerlist->routers, i);
if (router_is_me(router))
return router;
}
return NULL;
}
int
router_is_unreliable(routerinfo_t *router, int need_uptime, int need_capacity)
{
if (need_uptime && router->uptime < ROUTER_REQUIRED_MIN_UPTIME)
return 1;
if (need_capacity && router->bandwidthcapacity < ROUTER_REQUIRED_MIN_BANDWIDTH)
return 1;
return 0;
}
static void
routerlist_sl_remove_unreliable_routers(smartlist_t *sl)
{
int i;
routerinfo_t *router;
for (i = 0; i < smartlist_len(sl); ++i) {
router = smartlist_get(sl, i);
if (router_is_unreliable(router, 1, 0)) {
log(LOG_DEBUG, "Router '%s' has insufficient uptime; deleting.",
router->nickname);
smartlist_del(sl, i--);
}
}
}
routerinfo_t *
routerlist_sl_choose_by_bandwidth(smartlist_t *sl)
{
int i;
routerinfo_t *router;
smartlist_t *bandwidths;
uint32_t this_bw, tmp, total_bw=0, rand_bw;
uint32_t *p;
bandwidths = smartlist_create();
for (i = 0; i < smartlist_len(sl); ++i) {
router = smartlist_get(sl, i);
this_bw = (router->bandwidthcapacity < router->bandwidthrate) ?
router->bandwidthcapacity : router->bandwidthrate;
if (this_bw > 800000)
this_bw = 800000; /* if they claim something huge, don't believe it */
p = tor_malloc(sizeof(uint32_t));
*p = this_bw;
smartlist_add(bandwidths, p);
total_bw += this_bw;
// log_fn(LOG_INFO,"Recording bw %d for node %s.", this_bw, router->nickname);
}
if (!total_bw) {
SMARTLIST_FOREACH(bandwidths, uint32_t*, p, tor_free(p));
smartlist_free(bandwidths);
return smartlist_choose(sl);
}
rand_bw = crypto_pseudo_rand_int(total_bw);
// log_fn(LOG_INFO,"Total bw %d. Randomly chose %d.", total_bw, rand_bw);
tmp = 0;
for (i=0; ; i++) {
tor_assert(i < smartlist_len(sl));
p = smartlist_get(bandwidths, i);
tmp += *p;
router = smartlist_get(sl, i);
// log_fn(LOG_INFO,"Considering %s. tmp = %d.", router->nickname, tmp);
if (tmp >= rand_bw)
break;
}
SMARTLIST_FOREACH(bandwidths, uint32_t*, p, tor_free(p));
smartlist_free(bandwidths);
router = smartlist_get(sl, i);
// log_fn(LOG_INFO,"Picked %s.", router->nickname);
return router;
}
/** Return a random running router from the routerlist. If any node
* named in <b>preferred</b> is available, pick one of those. Never
* pick a node named in <b>excluded</b>, or whose routerinfo is in
* <b>excludedsmartlist</b>, even if they are the only nodes
* available. If <b>strict</b> is true, never pick any node besides
* those in <b>preferred</b>.
*/
routerinfo_t *router_choose_random_node(const char *preferred,
const char *excluded,
smartlist_t *excludedsmartlist,
int need_uptime, int need_capacity,
int allow_unverified, int strict)
{
smartlist_t *sl, *excludednodes;
routerinfo_t *choice;
excludednodes = smartlist_create();
add_nickname_list_to_smartlist(excludednodes,excluded,0);
/* try the preferred nodes first */
sl = smartlist_create();
add_nickname_list_to_smartlist(sl,preferred,1);
smartlist_subtract(sl,excludednodes);
if (excludedsmartlist)
smartlist_subtract(sl,excludedsmartlist);
if (need_uptime)
routerlist_sl_remove_unreliable_routers(sl);
if (need_capacity)
choice = routerlist_sl_choose_by_bandwidth(sl);
else
choice = smartlist_choose(sl);
smartlist_free(sl);
if (!choice && !strict) {
sl = smartlist_create();
router_add_running_routers_to_smartlist(sl, allow_unverified,
need_uptime, need_capacity);
smartlist_subtract(sl,excludednodes);
if (excludedsmartlist)
smartlist_subtract(sl,excludedsmartlist);
if (need_uptime)
routerlist_sl_remove_unreliable_routers(sl);
if (need_capacity)
choice = routerlist_sl_choose_by_bandwidth(sl);
else
choice = smartlist_choose(sl);
smartlist_free(sl);
}
smartlist_free(excludednodes);
if (!choice)
log_fn(LOG_WARN,"No available nodes when trying to choose node. Failing.");
return choice;
}
/** Return the router in our routerlist whose address is <b>addr</b> and
* whose OR port is <b>port</b>. Return NULL if no such router is known.
*/
routerinfo_t *router_get_by_addr_port(uint32_t addr, uint16_t port) {
int i;
routerinfo_t *router;
if (!routerlist)
return NULL;
for (i=0;i<smartlist_len(routerlist->routers);i++) {
router = smartlist_get(routerlist->routers, i);
if ((router->addr == addr) && (router->or_port == port))
return router;
}
return NULL;
}
/** Return true iff the digest of <b>router</b>'s identity key,
* encoded in hexadecimal, matches <b>hexdigest</b> (which is
* optionally prefixed with a single dollar sign). Return false if
* <b>hexdigest</b> is malformed, or it doesn't match. */
static INLINE int router_hex_digest_matches(routerinfo_t *router,
const char *hexdigest)
{
char digest[DIGEST_LEN];
tor_assert(hexdigest);
if (hexdigest[0] == '$')
++hexdigest;
if (strlen(hexdigest) != HEX_DIGEST_LEN ||
base16_decode(digest, DIGEST_LEN, hexdigest, HEX_DIGEST_LEN)<0)
return 0;
else
return (!memcmp(digest, router->identity_digest, DIGEST_LEN));
}
/* Return true if <b>router</b>'s nickname matches <b>nickname</b>
* (case-insensitive), or if <b>router's</b> identity key digest
* matches a hexadecimal value stored in <b>nickname</b>. Return
* false otherwise.*/
int router_nickname_matches(routerinfo_t *router, const char *nickname)
{
if (nickname[0]!='$' && !strcasecmp(router->nickname, nickname))
return 1;
else
return router_hex_digest_matches(router, nickname);
}
/** Return the router in our routerlist whose (case-insensitive)
* nickname or (case-sensitive) hexadecimal key digest is
* <b>nickname</b>. Return NULL if no such router is known.
*/
routerinfo_t *router_get_by_nickname(const char *nickname)
{
int i, maybedigest;
routerinfo_t *router;
char digest[DIGEST_LEN];
tor_assert(nickname);
if (!routerlist)
return NULL;
if (nickname[0] == '$')
return router_get_by_hexdigest(nickname);
maybedigest = (strlen(nickname) == HEX_DIGEST_LEN) &&
(base16_decode(digest,DIGEST_LEN,nickname,HEX_DIGEST_LEN) == 0);
for (i=0;i<smartlist_len(routerlist->routers);i++) {
router = smartlist_get(routerlist->routers, i);
if (0 == strcasecmp(router->nickname, nickname) ||
(maybedigest && 0 == memcmp(digest, router->identity_digest,
DIGEST_LEN)))
return router;
}
return NULL;
}
/** Return true iff <b>digest</b> is the digest of the identity key of
* a trusted directory. */
int router_digest_is_trusted_dir(const char *digest) {
if (!trusted_dir_servers)
return 0;
SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ent,
if (!memcmp(digest, ent->digest, DIGEST_LEN)) return 1);
return 0;
}
/** Return the router in our routerlist whose hexadecimal key digest
* is <b>hexdigest</b>. Return NULL if no such router is known. */
routerinfo_t *router_get_by_hexdigest(const char *hexdigest) {
char digest[DIGEST_LEN];
tor_assert(hexdigest);
if (!routerlist)
return NULL;
if (hexdigest[0]=='$')
++hexdigest;
if (strlen(hexdigest) != HEX_DIGEST_LEN ||
base16_decode(digest,DIGEST_LEN,hexdigest,HEX_DIGEST_LEN) < 0)
return NULL;
return router_get_by_digest(digest);
}
/** Return the router in our routerlist whose 20-byte key digest
* is <b>hexdigest</b>. Return NULL if no such router is known. */
routerinfo_t *router_get_by_digest(const char *digest) {
int i;
routerinfo_t *router;
tor_assert(digest);
if (!routerlist) return NULL;
for (i=0;i<smartlist_len(routerlist->routers);i++) {
router = smartlist_get(routerlist->routers, i);
if (0 == memcmp(router->identity_digest, digest, DIGEST_LEN))
return router;
}
return NULL;
}
/** Set *<b>prouterlist</b> to the current list of all known routers. */
void router_get_routerlist(routerlist_t **prouterlist) {
*prouterlist = routerlist;
}
/** Return the publication time on the current routerlist, or 0 if we have no
* routerlist. */
time_t routerlist_get_published_time(void) {
return routerlist ? routerlist->published_on : 0;
}
/** Free all storage held by <b>router</b>. */
void routerinfo_free(routerinfo_t *router)
{
if (!router)
return;
tor_free(router->address);
tor_free(router->nickname);
tor_free(router->platform);
if (router->onion_pkey)
crypto_free_pk_env(router->onion_pkey);
if (router->identity_pkey)
crypto_free_pk_env(router->identity_pkey);
if (router->declared_family) {
SMARTLIST_FOREACH(router->declared_family, char *, s, tor_free(s));
smartlist_free(router->declared_family);
}
addr_policy_free(router->exit_policy);
tor_free(router);
}
/** Allocate a fresh copy of <b>router</b> */
routerinfo_t *routerinfo_copy(const routerinfo_t *router)
{
routerinfo_t *r;
addr_policy_t **e, *tmp;
r = tor_malloc(sizeof(routerinfo_t));
memcpy(r, router, sizeof(routerinfo_t));
r->address = tor_strdup(r->address);
r->nickname = tor_strdup(r->nickname);
r->platform = tor_strdup(r->platform);
if (r->onion_pkey)
r->onion_pkey = crypto_pk_dup_key(r->onion_pkey);
if (r->identity_pkey)
r->identity_pkey = crypto_pk_dup_key(r->identity_pkey);
e = &r->exit_policy;
while (*e) {
tmp = tor_malloc(sizeof(addr_policy_t));
memcpy(tmp,*e,sizeof(addr_policy_t));
*e = tmp;
(*e)->string = tor_strdup((*e)->string);
e = & ((*e)->next);
}
if (r->declared_family) {
r->declared_family = smartlist_create();
SMARTLIST_FOREACH(router->declared_family, const char *, s,
smartlist_add(r->declared_family, tor_strdup(s)));
}
return r;
}
/** Free all storage held by a routerlist <b>rl</b> */
void routerlist_free(routerlist_t *rl)
{
SMARTLIST_FOREACH(rl->routers, routerinfo_t *, r,
routerinfo_free(r));
smartlist_free(rl->routers);
tor_free(rl->software_versions);
tor_free(rl);
}
/** Mark the router with ID <b>digest</b> as non-running in our routerlist. */
void router_mark_as_down(const char *digest) {
routerinfo_t *router;
tor_assert(digest);
SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, d,
if (!memcmp(d->digest, digest, DIGEST_LEN))
d->is_running = 0);
router = router_get_by_digest(digest);
if (!router) /* we don't seem to know about him in the first place */
return;
log_fn(LOG_DEBUG,"Marking router '%s' as down.",router->nickname);
if (router_is_me(router))
log_fn(LOG_WARN, "We just marked ourself as down. Are your external addresses reachable?");
router->is_running = 0;
router->status_set_at = time(NULL);
}
/** Add <b>router</b> to the routerlist, if we don't already have it. Replace
* older entries (if any) with the same name. Note: Callers should not hold
* their pointers to <b>router</b> after invoking this function; <b>router</b>
* will either be inserted into the routerlist or freed. Returns 0 if the
* router was added; -1 if it was not.
*/
static int
router_add_to_routerlist(routerinfo_t *router) {
int i;
routerinfo_t *r;
char id_digest[DIGEST_LEN];
tor_assert(routerlist);
crypto_pk_get_digest(router->identity_pkey, id_digest);
/* If we have a router with this name, and the identity key is the same,
* choose the newer one. If the identity key has changed, drop the router.
*/
for (i = 0; i < smartlist_len(routerlist->routers); ++i) {
r = smartlist_get(routerlist->routers, i);
if (!crypto_pk_cmp_keys(router->identity_pkey, r->identity_pkey)) {
if (router->published_on > r->published_on) {
log_fn(LOG_DEBUG, "Replacing entry for router '%s/%s' [%s]",
router->nickname, r->nickname, hex_str(id_digest,DIGEST_LEN));
/* Remember whether we trust this router as a dirserver. */
/* If the address hasn't changed; no need to re-resolve. */
if (!strcasecmp(r->address, router->address))
router->addr = r->addr;
routerinfo_free(r);
smartlist_set(routerlist->routers, i, router);
return 0;
} else {
log_fn(LOG_DEBUG, "Skipping old entry for router '%s'",
router->nickname);
/* Update the is_running status to whatever we were told. */
r->is_running = router->is_running;
routerinfo_free(router);
return -1;
}
} else if (!strcasecmp(router->nickname, r->nickname)) {
/* nicknames match, keys don't. */
if (router->is_verified) {
/* The new verified router replaces the old one; remove the
* old one. And carry on to the end of the list, in case
* there are more old unverified routers with this nickname
*/
/* mark-for-close connections using the old key, so we can
* make new ones with the new key.
*/
connection_t *conn;
while ((conn = connection_get_by_identity_digest(r->identity_digest,
CONN_TYPE_OR))) {
log_fn(LOG_INFO,"Closing conn to obsolete router '%s'", r->nickname);
connection_mark_for_close(conn);
}
routerinfo_free(r);
smartlist_del_keeporder(routerlist->routers, i--);
} else if (r->is_verified) {
/* Can't replace a verified router with an unverified one. */
log_fn(LOG_DEBUG, "Skipping unverified entry for verified router '%s'",
router->nickname);
routerinfo_free(router);
return -1;
}
}
}
/* We haven't seen a router with this name before. Add it to the end of
* the list. */
smartlist_add(routerlist->routers, router);
return 0;
}
/** Remove any routers from the routerlist that are more than <b>age</b>
* seconds old.
*
* (This function is just like dirserv_remove_old_servers. One day we should
* merge them.)
*/
void
routerlist_remove_old_routers(int age)
{
int i;
time_t cutoff;
routerinfo_t *router;
if (!routerlist)
return;
cutoff = time(NULL) - age;
for (i = 0; i < smartlist_len(routerlist->routers); ++i) {
router = smartlist_get(routerlist->routers, i);
if (router->published_on <= cutoff) {
/* Too old. Remove it. */
log_fn(LOG_INFO,"Forgetting obsolete routerinfo for router '%s'", router->nickname);
routerinfo_free(router);
smartlist_del(routerlist->routers, i--);
}
}
}
/*
* Code to parse router descriptors and directories.
*/
/** Add to the current routerlist each router stored in the
* signed directory <b>s</b>. If pkey is provided, check the signature against
* pkey; else check against the pkey of the signing directory server.
*
* If <b>dir_is_recent</b> is non-zero, then examine the
* Recommended-versions line and take appropriate action.
*
* If <b>dir_is_cached</b> is non-zero, then we're reading it
* from the cache so don't bother to re-write it to the cache.
*/
int router_load_routerlist_from_directory(const char *s,
crypto_pk_env_t *pkey,
int dir_is_recent,
int dir_is_cached)
{
routerlist_t *new_list = NULL;
if (router_parse_routerlist_from_directory(s, &new_list, pkey,
dir_is_recent,
!dir_is_cached)) {
log_fn(LOG_WARN, "Couldn't parse directory.");
return -1;
}
if (routerlist) {
SMARTLIST_FOREACH(new_list->routers, routerinfo_t *, r,
router_add_to_routerlist(r));
smartlist_clear(new_list->routers);
routerlist->published_on = new_list->published_on;
tor_free(routerlist->software_versions);
routerlist->software_versions = new_list->software_versions;
new_list->software_versions = NULL;
routerlist_free(new_list);
} else {
routerlist = new_list;
}
if (router_resolve_routerlist(routerlist)) {
log_fn(LOG_WARN, "Error resolving routerlist");
return -1;
}
if (get_options()->AuthoritativeDir) {
/* Learn about the descriptors in the directory. */
dirserv_load_from_directory_string(s);
}
return 0;
}
/** Helper function: resolve the hostname for <b>router</b>. */
static int
router_resolve(routerinfo_t *router)
{
if (tor_lookup_hostname(router->address, &router->addr) != 0
|| !router->addr) {
log_fn(LOG_WARN,"Could not resolve address for router '%s' at %s",
router->nickname, router->address);
return -1;
}
router->addr = ntohl(router->addr); /* get it back into host order */
return 0;
}
/** Helper function: resolve every router in rl, and ensure that our own
* routerinfo is at the front.
*/
static int
router_resolve_routerlist(routerlist_t *rl)
{
int i, remove;
routerinfo_t *r;
if (!rl)
rl = routerlist;
i = 0;
if ((r = router_get_my_routerinfo())) {
smartlist_insert(rl->routers, 0, routerinfo_copy(r));
++i;
}
for ( ; i < smartlist_len(rl->routers); ++i) {
remove = 0;
r = smartlist_get(rl->routers,i);
if (router_is_me(r)) {
remove = 1;
} else if (r->addr) {
/* already resolved. */
} else if (router_resolve(r)) {
log_fn(LOG_WARN, "Couldn't resolve router '%s' at '%s'; not using",
r->nickname, r->address);
remove = 1;
}
if (remove) {
routerinfo_free(r);
smartlist_del_keeporder(rl->routers, i--);
}
}
return 0;
}
/** Decide whether a given addr:port is definitely accepted, definitely
* rejected, or neither by a given policy. If <b>addr</b> is 0, we
* don't know the IP of the target address. If <b>port</b> is 0, we
* don't know the port of the target address.
*
* Returns -1 for "rejected", 0 for "accepted", 1 for "maybe" (since IP or
* port is unknown).
*/
int router_compare_addr_to_addr_policy(uint32_t addr, uint16_t port,
addr_policy_t *policy)
{
int maybe_reject = 0;
int maybe_accept = 0;
int match = 0;
int maybe = 0;
addr_policy_t *tmpe;
for (tmpe=policy; tmpe; tmpe=tmpe->next) {
// log_fn(LOG_DEBUG,"Considering exit policy %s", tmpe->string);
maybe = 0;
if (!addr) {
/* Address is unknown. */
if ((port >= tmpe->prt_min && port <= tmpe->prt_max) ||
(!port && tmpe->prt_min<=1 && tmpe->prt_max>=65535)) {
/* The port definitely matches. */
if (tmpe->msk == 0) {
match = 1;
} else {
maybe = 1;
}
} else if (!port) {
/* The port maybe matches. */
maybe = 1;
}
} else {
/* Address is known */
if ((addr & tmpe->msk) == (tmpe->addr & tmpe->msk)) {
if (port >= tmpe->prt_min && port <= tmpe->prt_max) {
/* Exact match for the policy */
match = 1;
} else if (!port) {
maybe = 1;
}
}
}
if (maybe) {
if (tmpe->policy_type == ADDR_POLICY_REJECT)
maybe_reject = 1;
else
maybe_accept = 1;
}
if (match) {
// struct in_addr in;
// in.s_addr = htonl(addr);
// log_fn(LOG_DEBUG,"Address %s:%d matches policy '%s'",
// inet_ntoa(in), port, tmpe->string);
if (tmpe->policy_type == ADDR_POLICY_ACCEPT) {
/* If we already hit a clause that might trigger a 'reject', than we
* can't be sure of this certain 'accept'.*/
return maybe_reject ? ADDR_POLICY_UNKNOWN : ADDR_POLICY_ACCEPTED;
} else {
return maybe_accept ? ADDR_POLICY_UNKNOWN : ADDR_POLICY_REJECTED;
}
}
}
/* accept all by default. */
return maybe_reject ? ADDR_POLICY_UNKNOWN : ADDR_POLICY_ACCEPTED;
}
/** Return 1 if all running sufficiently-stable routers will reject
* addr:port, return 0 if any might accept it. */
int router_exit_policy_all_routers_reject(uint32_t addr, uint16_t port,
int need_uptime) {
int i;
routerinfo_t *router;
if (!routerlist) return 1;
for (i=0;i<smartlist_len(routerlist->routers);i++) {
router = smartlist_get(routerlist->routers, i);
if (router->is_running &&
!router_is_unreliable(router, need_uptime, 0) &&
router_compare_addr_to_addr_policy(
addr, port, router->exit_policy) != ADDR_POLICY_REJECTED)
return 0; /* this one could be ok. good enough. */
}
return 1; /* all will reject. */
}
/**
* If <b>policy</b> implicitly allows connections to any port in the
* IP set <b>addr</b>/<b>mask</b>, then set *<b>policy_out</b> to the
* part of the policy that allows it, and return 1. Else return 0.
*
* A policy allows an IP:Port combination <em>implicitly</em> if
* it is included in a *: pattern, or in a fallback pattern.
*/
static int
policy_includes_addr_mask_implicitly(addr_policy_t *policy,
uint32_t addr, uint32_t mask,
addr_policy_t **policy_out)
{
uint32_t addr2;
tor_assert(policy_out);
addr &= mask;
addr2 = addr | ~mask;
for (; policy; policy=policy->next) {
/* Does this policy cover all of the address range we're looking at? */
/* Boolean logic time: range X is contained in range Y if, for
* each bit B, all possible values of B in X are values of B in Y.
* In "addr", we have every fixed bit set to its value, and every
* free bit set to 0. In "addr2", we have every fixed bit set to
* its value, and every free bit set to 1. So if addr and addr2 are
* both in the policy, the range is covered by the policy.
*/
if ((policy->addr & policy->msk) == (addr & policy->msk) &&
(policy->addr & policy->msk) == (addr2 & policy->msk) &&
(policy->prt_min <= 1 && policy->prt_max == 65535)) {
return 0;
}
/* Does this policy cover some of the address range we're looking at? */
/* Boolean logic time: range X and range Y intersect if there is
* some z such that z & Xmask == Xaddr and z & Ymask == Yaddr.
* This is FALSE iff there is some bit b where Xmask == yMask == 1
* and Xaddr != Yaddr. So if X intersects with Y iff at every
* place where Xmask&Ymask==1, Xaddr == Yaddr, or equivalently,
* Xaddr&Xmask&Ymask == Yaddr&Xmask&Ymask.
*/
if ((policy->addr & policy->msk & mask) == (addr & policy->msk) &&
policy->policy_type == ADDR_POLICY_ACCEPT) {
*policy_out = policy;
return 1;
}
}
*policy_out = NULL;
return 1;
}
/** If <b>policy</b> implicitly allows connections to any port on
* 127.*, 192.168.*, etc, then warn (if <b>warn</b> is set) and return
* true. Else return false.
**/
int
exit_policy_implicitly_allows_local_networks(addr_policy_t *policy,
int warn)
{
addr_policy_t *p;
int r=0,i;
static struct {
uint32_t addr; uint32_t mask; const char *network;
} private_networks[] = {
{ 0x7f000000, 0xff000000, "localhost (127.x)" },
{ 0x0a000000, 0xff000000, "addresses in private network 10.x" },
{ 0xa9fe0000, 0xffff0000, "addresses in private network 169.254.x" },
{ 0xac100000, 0xfff00000, "addresses in private network 172.16.x" },
{ 0xc0a80000, 0xffff0000, "addresses in private network 192.168.x" },
{ 0,0,NULL},
};
for (i=0; private_networks[i].addr; ++i) {
p = NULL;
if (policy_includes_addr_mask_implicitly(
policy, private_networks[i].addr, private_networks[i].mask, &p)) {
if (warn)
log_fn(LOG_WARN, "Exit policy %s implicitly accepts %s",
p?p->string:"(default)",
private_networks[i].network);
r = 1;
}
}
return r;
}
/** Return true iff <b>router</b> does not permit exit streams.
*/
int router_exit_policy_rejects_all(routerinfo_t *router) {
return router_compare_addr_to_addr_policy(0, 0, router->exit_policy)
== ADDR_POLICY_REJECTED;
}
/** Release all space held in <b>rr</b>. */
void running_routers_free(running_routers_t *rr)
{
tor_assert(rr);
if (rr->running_routers) {
SMARTLIST_FOREACH(rr->running_routers, char *, s, tor_free(s));
smartlist_free(rr->running_routers);
}
tor_free(rr);
}
/** Update the running/not-running status of every router in <b>list</b>, based
* on the contents of <b>rr</b>. */
/* Note: this function is not yet used, since nobody publishes just
* running-router lists yet. */
void routerlist_update_from_runningrouters(routerlist_t *list,
running_routers_t *rr)
{
routerinfo_t *me = router_get_my_routerinfo();
smartlist_t *all_routers;
if (!list)
return;
if (list->published_on >= rr->published_on)
return;
if (list->running_routers_updated_on >= rr->published_on)
return;
all_routers = smartlist_create();
if (me) /* learn if the dirservers think I'm verified */
smartlist_add(all_routers, me);
smartlist_add_all(all_routers,list->routers);
SMARTLIST_FOREACH(rr->running_routers, const char *, cp,
routers_update_status_from_entry(all_routers, rr->published_on,
cp, rr->is_running_routers_format));
smartlist_free(all_routers);
list->running_routers_updated_on = rr->published_on;
}
/** Update the is_running and is_verified fields of the router <b>router</b>,
* based in its status in the list of strings stored in <b>running_list</b>.
* All entries in <b>running_list</b> follow one of these formats:
* <ol><li> <b>nickname</b> -- router is running and verified.
* (running-routers format)
* <li> !<b>nickname</b> -- router is not-running and verified.
* (running-routers format)
* <li> <b>nickname</b>=$<b>hexdigest</b> -- router is running and
* verified. (router-status format)
* (router-status format)
* <li> !<b>nickname</b>=$<b>hexdigest</b> -- router is running and
* verified. (router-status format)
* <li> !<b>nickname</b> -- router is not-running and verified.
* <li> $<b>hexdigest</b> -- router is running and unverified.
* <li> !$<b>hexdigest</b> -- router is not-running and unverified.
* </ol>
*
* Return 1 if we found router in running_list, else return 0.
*/
int routers_update_status_from_entry(smartlist_t *routers,
time_t list_time,
const char *s,
int rr_format)
{
int is_running = 1;
int is_verified = 0;
int hex_digest_set = 0;
char nickname[MAX_NICKNAME_LEN+1];
char hexdigest[HEX_DIGEST_LEN+1];
char digest[DIGEST_LEN];
const char *cp, *end;
/* First, parse the entry. */
cp = s;
if (*cp == '!') {
is_running = 0;
++cp;
}
if (*cp != '$') {
/* It starts with a non-dollar character; that's a nickname. The nickname
* entry will either extend to a NUL (old running-routers format) or to an
* equals sign (new router-status format). */
is_verified = 1;
end = strchr(cp, '=');
if (!end)
end = strchr(cp,'\0');
tor_assert(end);
/* 'end' now points on character beyond the end of the nickname */
if (end == cp || end-cp > MAX_NICKNAME_LEN) {
log_fn(LOG_WARN, "Bad nickname length (%d) in router status entry (%s)",
(int)(end-cp), s);
return -1;
}
memcpy(nickname, cp, end-cp);
nickname[end-cp]='\0';
if (!is_legal_nickname(nickname)) {
log_fn(LOG_WARN, "Bad nickname (%s) in router status entry (%s)",
nickname, s);
return -1;
}
cp = end;
if (*cp == '=')
++cp;
}
/* 'end' now points to the start of a hex digest, or EOS. */
/* Parse the hexdigest portion of the status. */
if (*cp == '$') {
hex_digest_set = 1;
++cp;
if (strlen(cp) != HEX_DIGEST_LEN) {
log_fn(LOG_WARN, "Bad length (%d) on digest in router status entry (%s)",
(int)strlen(cp), s);
return -1;
}
strlcpy(hexdigest, cp, sizeof(hexdigest));
if (base16_decode(digest, DIGEST_LEN, hexdigest, HEX_DIGEST_LEN)<0) {
log_fn(LOG_WARN, "Invalid digest in router status entry (%s)", s);
return -1;
}
}
/* Make sure that the entry was in the right format. */
if (rr_format) {
if (is_verified == hex_digest_set) {
log_fn(LOG_WARN, "Invalid syntax for running-routers member (%s)", s);
return -1;
}
} else {
if (!hex_digest_set) {
log_fn(LOG_WARN, "Invalid syntax for router-status member (%s)", s);
return -1;
}
}
/* Okay, we're done parsing. For all routers that match, update their status.
*/
SMARTLIST_FOREACH(routers, routerinfo_t *, r,
{
int nickname_matches = is_verified && !strcasecmp(r->nickname, nickname);
int digest_matches = !memcmp(digest, r->identity_digest, DIGEST_LEN);
if (nickname_matches && (digest_matches||rr_format))
r->is_verified = 1;
else if (digest_matches)
r->is_verified = 0;
if (digest_matches || (nickname_matches&&rr_format))
if (r->status_set_at < list_time) {
r->is_running = is_running;
r->status_set_at = time(NULL);
}
});
return 0;
}
/** As router_update_status_from_entry, but consider all entries in
* running_list. */
int
router_update_status_from_smartlist(routerinfo_t *router,
time_t list_time,
smartlist_t *running_list,
int rr_format)
{
smartlist_t *rl;
rl = smartlist_create();
smartlist_add(rl,router);
SMARTLIST_FOREACH(running_list, const char *, cp,
routers_update_status_from_entry(rl,list_time,cp,rr_format));
smartlist_free(rl);
return 0;
}
/** Add to the list of authorized directory servers one at
* <b>address</b>:<b>port</b>, with identity key <b>digest</b>. */
void
add_trusted_dir_server(const char *address, uint16_t port, const char *digest)
{
trusted_dir_server_t *ent;
uint32_t a;
if (!trusted_dir_servers)
trusted_dir_servers = smartlist_create();
if (tor_lookup_hostname(address, &a)) {
log_fn(LOG_WARN, "Unable to lookup address for directory server at %s",
address);
return;
}
ent = tor_malloc(sizeof(trusted_dir_server_t));
ent->address = tor_strdup(address);
ent->addr = ntohl(a);
ent->dir_port = port;
ent->is_running = 1;
memcpy(ent->digest, digest, DIGEST_LEN);
smartlist_add(trusted_dir_servers, ent);
}
void clear_trusted_dir_servers(void)
{
if (trusted_dir_servers) {
SMARTLIST_FOREACH(trusted_dir_servers, trusted_dir_server_t *, ent,
{ tor_free(ent->address); tor_free(ent); });
smartlist_clear(trusted_dir_servers);
} else {
trusted_dir_servers = smartlist_create();
}
}
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