/* Copyright (c) 2001 Matej Pfajfar.
* Copyright (c) 2001-2004, Roger Dingledine.
* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. */
/* See LICENSE for licensing information */
/* $Id$ */
const char router_c_id[] =
"$Id$";
#include "or.h"
/**
* \file router.c
* \brief OR functionality, including key maintenance, generating
* and uploading server descriptors, retrying OR connections.
**/
extern long stats_n_seconds_working;
/* Exposed for test.c. */ void get_platform_str(char *platform, size_t len);
/************************************************************/
/*****
* Key management: ORs only.
*****/
/** Private keys for this OR. There is also an SSL key managed by tortls.c.
*/
static tor_mutex_t *key_lock=NULL;
static time_t onionkey_set_at=0; /* When was onionkey last changed? */
static crypto_pk_env_t *onionkey=NULL;
static crypto_pk_env_t *lastonionkey=NULL;
static crypto_pk_env_t *identitykey=NULL;
/** Replace the current onion key with <b>k</b>. Does not affect lastonionkey;
* to update onionkey correctly, call rotate_onion_key().
*/
void
set_onion_key(crypto_pk_env_t *k)
{
tor_mutex_acquire(key_lock);
onionkey = k;
onionkey_set_at = time(NULL);
tor_mutex_release(key_lock);
mark_my_descriptor_dirty();
}
/** Return the current onion key. Requires that the onion key has been
* loaded or generated. */
crypto_pk_env_t *
get_onion_key(void)
{
tor_assert(onionkey);
return onionkey;
}
/** Store a copy of the current onion key into *<b>key</b>, and a copy
* of the most recent onion key into *<b>last</b>.
*/
void
dup_onion_keys(crypto_pk_env_t **key, crypto_pk_env_t **last)
{
tor_assert(key);
tor_assert(last);
tor_mutex_acquire(key_lock);
tor_assert(onionkey);
*key = crypto_pk_dup_key(onionkey);
if (lastonionkey)
*last = crypto_pk_dup_key(lastonionkey);
else
*last = NULL;
tor_mutex_release(key_lock);
}
/** Return the time when the onion key was last set. This is either the time
* when the process launched, or the time of the most recent key rotation since
* the process launched.
*/
time_t
get_onion_key_set_at(void)
{
return onionkey_set_at;
}
/** Set the current identity key to k.
*/
void
set_identity_key(crypto_pk_env_t *k)
{
if (identitykey)
crypto_free_pk_env(identitykey);
identitykey = k;
}
/** Returns the current identity key; requires that the identity key has been
* set.
*/
crypto_pk_env_t *
get_identity_key(void)
{
tor_assert(identitykey);
return identitykey;
}
/** Return true iff the identity key has been set. */
int
identity_key_is_set(void)
{
return identitykey != NULL;
}
/** Replace the previous onion key with the current onion key, and generate
* a new previous onion key. Immediately after calling this function,
* the OR should:
* - schedule all previous cpuworkers to shut down _after_ processing
* pending work. (This will cause fresh cpuworkers to be generated.)
* - generate and upload a fresh routerinfo.
*/
void
rotate_onion_key(void)
{
char fname[512];
char fname_prev[512];
crypto_pk_env_t *prkey;
tor_snprintf(fname,sizeof(fname),
"%s/keys/secret_onion_key",get_options()->DataDirectory);
tor_snprintf(fname_prev,sizeof(fname_prev),
"%s/keys/secret_onion_key.old",get_options()->DataDirectory);
if (!(prkey = crypto_new_pk_env())) {
log_err(LD_GENERAL,"Error creating crypto environment.");
goto error;
}
if (crypto_pk_generate_key(prkey)) {
log_err(LD_BUG,"Error generating onion key");
goto error;
}
if (file_status(fname) == FN_FILE) {
if (replace_file(fname, fname_prev))
goto error;
}
if (crypto_pk_write_private_key_to_filename(prkey, fname)) {
log_err(LD_FS,"Couldn't write generated key to \"%s\".", fname);
goto error;
}
log_info(LD_GENERAL, "Rotating onion key");
tor_mutex_acquire(key_lock);
if (lastonionkey)
crypto_free_pk_env(lastonionkey);
lastonionkey = onionkey;
onionkey = prkey;
onionkey_set_at = time(NULL);
tor_mutex_release(key_lock);
mark_my_descriptor_dirty();
return;
error:
log_warn(LD_GENERAL, "Couldn't rotate onion key.");
}
/* Read an RSA secret key key from a file that was once named fname_old,
* but is now named fname_new. Rename the file from old to new as needed.
*/
static crypto_pk_env_t *
init_key_from_file_name_changed(const char *fname_old,
const char *fname_new)
{
if (file_status(fname_new) == FN_FILE || file_status(fname_old) != FN_FILE)
/* The new filename is there, or both are, or neither is. */
return init_key_from_file(fname_new);
/* The old filename exists, and the new one doesn't. Rename and load. */
if (rename(fname_old, fname_new) < 0) {
log_warn(LD_FS, "Couldn't rename \"%s\" to \"%s\": %s",
fname_old, fname_new, strerror(errno));
return NULL;
}
return init_key_from_file(fname_new);
}
/** Try to read an RSA key from <b>fname</b>. If <b>fname</b> doesn't exist,
* create a new RSA key and save it in <b>fname</b>. Return the read/created
* key, or NULL on error.
*/
crypto_pk_env_t *
init_key_from_file(const char *fname)
{
crypto_pk_env_t *prkey = NULL;
FILE *file = NULL;
if (!(prkey = crypto_new_pk_env())) {
log_err(LD_GENERAL,"Error creating crypto environment.");
goto error;
}
switch (file_status(fname)) {
case FN_DIR:
case FN_ERROR:
log_err(LD_FS,"Can't read key from \"%s\"", fname);
goto error;
case FN_NOENT:
log_info(LD_GENERAL, "No key found in \"%s\"; generating fresh key.",
fname);
if (crypto_pk_generate_key(prkey)) {
log_err(LD_GENERAL,"Error generating onion key");
goto error;
}
if (crypto_pk_check_key(prkey) <= 0) {
log_err(LD_GENERAL,"Generated key seems invalid");
goto error;
}
log_info(LD_GENERAL, "Generated key seems valid");
if (crypto_pk_write_private_key_to_filename(prkey, fname)) {
log_err(LD_FS,"Couldn't write generated key to \"%s\".", fname);
goto error;
}
return prkey;
case FN_FILE:
if (crypto_pk_read_private_key_from_filename(prkey, fname)) {
log_err(LD_GENERAL,"Error loading private key.");
goto error;
}
return prkey;
default:
tor_assert(0);
}
error:
if (prkey)
crypto_free_pk_env(prkey);
if (file)
fclose(file);
return NULL;
}
/** Initialize all OR private keys, and the TLS context, as necessary.
* On OPs, this only initializes the tls context.
*/
int
init_keys(void)
{
/* XXX009 Two problems with how this is called:
* 1. It should be idempotent for servers, so we can call init_keys
* as much as we need to.
*/
char keydir[512];
char keydir2[512];
char fingerprint[FINGERPRINT_LEN+1];
/*nickname<space>fp\n\0 */
char fingerprint_line[MAX_NICKNAME_LEN+FINGERPRINT_LEN+3];
char *cp;
const char *mydesc, *datadir;
crypto_pk_env_t *prkey;
char digest[20];
or_options_t *options = get_options();
if (!key_lock)
key_lock = tor_mutex_new();
/* OP's don't need persistent keys; just make up an identity and
* initialize the TLS context. */
if (!server_mode(options)) {
if (!(prkey = crypto_new_pk_env()))
return -1;
if (crypto_pk_generate_key(prkey))
return -1;
set_identity_key(prkey);
/* Create a TLS context; default the client nickname to "client". */
if (tor_tls_context_new(get_identity_key(), 1,
options->Nickname ? options->Nickname : "client",
MAX_SSL_KEY_LIFETIME) < 0) {
log_err(LD_GENERAL,"Error creating TLS context for OP.");
return -1;
}
return 0;
}
/* Make sure DataDirectory exists, and is private. */
datadir = options->DataDirectory;
if (check_private_dir(datadir, CPD_CREATE)) {
return -1;
}
/* Check the key directory. */
tor_snprintf(keydir,sizeof(keydir),"%s/keys", datadir);
if (check_private_dir(keydir, CPD_CREATE)) {
return -1;
}
cp = keydir + strlen(keydir); /* End of string. */
/* 1. Read identity key. Make it if none is found. */
tor_snprintf(keydir,sizeof(keydir),"%s/keys/identity.key",datadir);
tor_snprintf(keydir2,sizeof(keydir2),"%s/keys/secret_id_key",datadir);
log_info(LD_GENERAL,"Reading/making identity key \"%s\"...",keydir2);
prkey = init_key_from_file_name_changed(keydir,keydir2);
if (!prkey) return -1;
set_identity_key(prkey);
/* 2. Read onion key. Make it if none is found. */
tor_snprintf(keydir,sizeof(keydir),"%s/keys/onion.key",datadir);
tor_snprintf(keydir2,sizeof(keydir2),"%s/keys/secret_onion_key",datadir);
log_info(LD_GENERAL,"Reading/making onion key \"%s\"...",keydir2);
prkey = init_key_from_file_name_changed(keydir,keydir2);
if (!prkey) return -1;
set_onion_key(prkey);
tor_snprintf(keydir,sizeof(keydir),"%s/keys/secret_onion_key.old",datadir);
if (file_status(keydir) == FN_FILE) {
prkey = init_key_from_file(keydir);
if (prkey)
lastonionkey = prkey;
}
/* 3. Initialize link key and TLS context. */
if (tor_tls_context_new(get_identity_key(), 1, options->Nickname,
MAX_SSL_KEY_LIFETIME) < 0) {
log_err(LD_GENERAL,"Error initializing TLS context");
return -1;
}
/* 4. Build our router descriptor. */
/* Must be called after keys are initialized. */
mydesc = router_get_my_descriptor();
if (!mydesc) {
log_err(LD_GENERAL,"Error initializing descriptor.");
return -1;
}
if (authdir_mode(options)) {
const char *m;
/* We need to add our own fingerprint so it gets recognized. */
if (dirserv_add_own_fingerprint(options->Nickname, get_identity_key())) {
log_err(LD_GENERAL,"Error adding own fingerprint to approved set");
return -1;
}
if (dirserv_add_descriptor(mydesc, &m) < 0) {
log_err(LD_GENERAL,"Unable to add own descriptor to directory: %s",
m?m:"<unknown error>");
return -1;
}
}
#if 0
tor_snprintf(keydir,sizeof(keydir),"%s/router.desc", datadir);
log_info(LD_GENERAL,"Dumping descriptor to \"%s\"...",keydir);
if (write_str_to_file(keydir, mydesc,0)) {
return -1;
}
#endif
/* 5. Dump fingerprint to 'fingerprint' */
tor_snprintf(keydir,sizeof(keydir),"%s/fingerprint", datadir);
log_info(LD_GENERAL,"Dumping fingerprint to \"%s\"...",keydir);
if (crypto_pk_get_fingerprint(get_identity_key(), fingerprint, 1)<0) {
log_err(LD_GENERAL,"Error computing fingerprint");
return -1;
}
tor_assert(strlen(options->Nickname) <= MAX_NICKNAME_LEN);
if (tor_snprintf(fingerprint_line, sizeof(fingerprint_line),
"%s %s\n",options->Nickname, fingerprint) < 0) {
log_err(LD_GENERAL,"Error writing fingerprint line");
return -1;
}
if (write_str_to_file(keydir, fingerprint_line, 0)) {
log_err(LD_FS, "Error writing fingerprint line to file");
return -1;
}
log(LOG_NOTICE, LD_GENERAL,
"Your Tor server's identity key fingerprint is '%s %s'",
options->Nickname, fingerprint);
if (!authdir_mode(options))
return 0;
/* 6. [authdirserver only] load approved-routers file */
tor_snprintf(keydir,sizeof(keydir),"%s/approved-routers", datadir);
log_info(LD_DIRSERV,"Loading approved fingerprints from \"%s\"...",keydir);
if (dirserv_parse_fingerprint_file(keydir) < 0) {
log_err(LD_GENERAL,"Error loading fingerprints");
return -1;
}
/* 6b. [authdirserver only] add own key to approved directories. */
crypto_pk_get_digest(get_identity_key(), digest);
if (!router_digest_is_trusted_dir(digest)) {
add_trusted_dir_server(options->Nickname, NULL,
(uint16_t)options->DirPort, digest,
options->V1AuthoritativeDir);
}
/* success */
return 0;
}
/* Keep track of whether we should upload our server descriptor,
* and what type of server we are.
*/
/** Whether we can reach our ORPort from the outside. */
static int can_reach_or_port = 0;
/** Whether we can reach our DirPort from the outside. */
static int can_reach_dir_port = 0;
/** Return 1 if or port is known reachable; else return 0. */
int
check_whether_orport_reachable(void)
{
or_options_t *options = get_options();
return clique_mode(options) ||
options->AssumeReachable ||
can_reach_or_port;
}
/** Return 1 if we don't have a dirport configured, or if it's reachable. */
int
check_whether_dirport_reachable(void)
{
or_options_t *options = get_options();
return !options->DirPort ||
options->AssumeReachable ||
we_are_hibernating() ||
can_reach_dir_port;
}
/** Look at a variety of factors, and return 0 if we don't want to
* advertise the fact that we have a DirPort open. Else return the
* DirPort we want to advertise. */
static int
decide_to_advertise_dirport(or_options_t *options, routerinfo_t *router)
{
if (!router->dir_port) /* short circuit the rest of the function */
return 0;
if (authdir_mode(options)) /* always publish */
return router->dir_port;
if (we_are_hibernating())
return 0;
if (!check_whether_dirport_reachable())
return 0;
if (router->bandwidthcapacity >= router->bandwidthrate) {
/* check if we might potentially hibernate. */
if (options->AccountingMax != 0)
return 0;
/* also check if we're advertising a small amount, and have
a "boring" DirPort. */
if (router->bandwidthrate < 50000 && router->dir_port > 1024)
return 0;
}
/* Sounds like a great idea. Let's publish it. */
return router->dir_port;
}
/** Some time has passed, or we just got new directory information.
* See if we currently believe our ORPort or DirPort to be
* unreachable. If so, launch a new test for it.
*
* For ORPort, we simply try making a circuit that ends at ourselves.
* Success is noticed in onionskin_answer().
*
* For DirPort, we make a connection via Tor to our DirPort and ask
* for our own server descriptor.
* Success is noticed in connection_dir_client_reached_eof().
*/
void
consider_testing_reachability(void)
{
routerinfo_t *me = router_get_my_routerinfo();
if (!me) {
log_warn(LD_BUG,
"Bug: router_get_my_routerinfo() did not find my routerinfo?");
return;
}
if (!check_whether_orport_reachable()) {
circuit_launch_by_router(CIRCUIT_PURPOSE_TESTING, me, 0, 1, 1);
}
if (!check_whether_dirport_reachable()) {
/* ask myself, via tor, for my server descriptor. */
directory_initiate_command_router(me, DIR_PURPOSE_FETCH_SERVERDESC,
1, "authority", NULL, 0);
}
}
/** Annotate that we found our ORPort reachable. */
void
router_orport_found_reachable(void)
{
if (!can_reach_or_port) {
if (!clique_mode(get_options()))
log_notice(LD_OR,"Self-testing indicates your ORPort is reachable from "
"the outside. Excellent.%s",
get_options()->PublishServerDescriptor ?
" Publishing server descriptor." : "");
can_reach_or_port = 1;
mark_my_descriptor_dirty();
consider_publishable_server(time(NULL), 1);
}
}
/** Annotate that we found our DirPort reachable. */
void
router_dirport_found_reachable(void)
{
if (!can_reach_dir_port) {
log_notice(LD_DIRSERV,"Self-testing indicates your DirPort is reachable "
"from the outside. Excellent.");
can_reach_dir_port = 1;
}
}
/** Our router has just moved to a new IP. Reset stats. */
void
server_has_changed_ip(void)
{
stats_n_seconds_working = 0;
can_reach_or_port = 0;
can_reach_dir_port = 0;
mark_my_descriptor_dirty();
}
/** Return true iff we believe ourselves to be an authoritative
* directory server.
*/
int
authdir_mode(or_options_t *options)
{
return options->AuthoritativeDir != 0;
}
/** Return true iff we try to stay connected to all ORs at once.
*/
int
clique_mode(or_options_t *options)
{
return authdir_mode(options);
}
/** Return true iff we are trying to be a server.
*/
int
server_mode(or_options_t *options)
{
if (options->ClientOnly) return 0;
return (options->ORPort != 0 || options->ORListenAddress);
}
/** Remember if we've advertised ourselves to the dirservers. */
static int server_is_advertised=0;
/** Return true iff we have published our descriptor lately.
*/
int
advertised_server_mode(void)
{
return server_is_advertised;
}
/**
* Called with a boolean: set whether we have recently published our
* descriptor.
*/
static void
set_server_advertised(int s)
{
server_is_advertised = s;
}
/** Return true iff we are trying to be a socks proxy. */
int
proxy_mode(or_options_t *options)
{
return (options->SocksPort != 0 || options->SocksListenAddress);
}
/** Decide if we're a publishable server. We are a publishable server if:
* - We don't have the ClientOnly option set
* and
* - We have the PublishServerDescriptor option set
* and
* - We have ORPort set
* and
* - We believe we are reachable from the outside; or
* - We have the AuthoritativeDirectory option set.
*/
static int
decide_if_publishable_server(time_t now)
{
or_options_t *options = get_options();
if (options->ClientOnly)
return 0;
if (!options->PublishServerDescriptor)
return 0;
if (!server_mode(options))
return 0;
if (options->AuthoritativeDir)
return 1;
return check_whether_orport_reachable();
}
/** Initiate server descriptor upload as reasonable (if server is publishable,
* etc). <b>force</b> is as for router_upload_dir_desc_to_dirservers.
*
* We need to rebuild the descriptor if it's dirty even if we're not
* uploading, because our reachability testing *uses* our descriptor to
* determine what IP address and ports to test.
*/
void
consider_publishable_server(time_t now, int force)
{
int rebuilt;
if (!server_mode(get_options()))
return;
rebuilt = router_rebuild_descriptor(0);
if (decide_if_publishable_server(now)) {
set_server_advertised(1);
if (rebuilt == 0)
router_upload_dir_desc_to_dirservers(force);
} else {
set_server_advertised(0);
}
}
/*
* Clique maintenance
*/
/** OR only: if in clique mode, try to open connections to all of the
* other ORs we know about. Otherwise, open connections to those we
* think are in clique mode.
*
* If <b>testing_reachability</b> is 0, try to open the connections
* but only if we don't already have one. If it's 1, then we're an
* auth dir server, and we should try to connect regardless of
* whether we already have a connection open -- but if <b>try_all</b>
* is 0, we want to load balance such that we only try a few connections
* per call.
*
* The load balancing is such that if we get called once every ten
* seconds, we will cycle through all the tests in 1280 seconds (a
* bit over 20 minutes).
*/
void
router_retry_connections(int testing_reachability, int try_all)
{
time_t now = time(NULL);
routerlist_t *rl = router_get_routerlist();
or_options_t *options = get_options();
static char ctr = 0;
tor_assert(server_mode(options));
SMARTLIST_FOREACH(rl->routers, routerinfo_t *, router, {
const char *id_digest = router->cache_info.identity_digest;
if (router_is_me(router))
continue;
if (!clique_mode(options) && !router_is_clique_mode(router))
continue;
if ((testing_reachability &&
(try_all || (((uint8_t)id_digest[0]) % 128) == ctr)) ||
(!testing_reachability &&
!connection_or_get_by_identity_digest(id_digest))) {
log_debug(LD_OR,"%sconnecting to %s at %s:%u.",
clique_mode(options) ? "(forced) " : "",
router->nickname, router->address, router->or_port);
/* Remember when we started trying to determine reachability */
if (!router->testing_since)
router->testing_since = now;
connection_or_connect(router->addr, router->or_port,
id_digest);
}
});
if (testing_reachability && !try_all) /* increment ctr */
ctr = (ctr + 1) % 128;
}
/** Return true iff this OR should try to keep connections open to all
* other ORs. */
int
router_is_clique_mode(routerinfo_t *router)
{
if (router_digest_is_trusted_dir(router->cache_info.identity_digest))
return 1;
return 0;
}
/*
* OR descriptor generation.
*/
/** My routerinfo. */
static routerinfo_t *desc_routerinfo = NULL;
/** Since when has our descriptor been "clean"? 0 if we need to regenerate it
* now. */
static time_t desc_clean_since = 0;
/** Boolean: do we need to regenerate the above? */
static int desc_needs_upload = 0;
/** OR only: If <b>force</b> is true, or we haven't uploaded this
* descriptor successfully yet, try to upload our signed descriptor to
* all the directory servers we know about.
*/
void
router_upload_dir_desc_to_dirservers(int force)
{
const char *s;
s = router_get_my_descriptor();
if (!s) {
log_warn(LD_GENERAL, "No descriptor; skipping upload");
return;
}
if (!get_options()->PublishServerDescriptor)
return;
if (!force && !desc_needs_upload)
return;
desc_needs_upload = 0;
directory_post_to_dirservers(DIR_PURPOSE_UPLOAD_DIR, s, strlen(s));
}
/** OR only: Check whether my exit policy says to allow connection to
* conn. Return 0 if we accept; non-0 if we reject.
*/
int
router_compare_to_my_exit_policy(connection_t *conn)
{
tor_assert(desc_routerinfo);
/* make sure it's resolved to something. this way we can't get a
'maybe' below. */
if (!conn->addr)
return -1;
return compare_addr_to_addr_policy(conn->addr, conn->port,
desc_routerinfo->exit_policy) != ADDR_POLICY_ACCEPTED;
}
/** Return true iff I'm a server and <b>digest</b> is equal to
* my identity digest. */
int
router_digest_is_me(const char *digest)
{
routerinfo_t *me = router_get_my_routerinfo();
if (!me || memcmp(me->cache_info.identity_digest, digest, DIGEST_LEN))
return 0;
return 1;
}
/** A wrapper around router_digest_is_me(). */
int
router_is_me(routerinfo_t *router)
{
return router_digest_is_me(router->cache_info.identity_digest);
}
/** Return true iff <b>fp</b> is a hex fingerprint of my identity digest. */
int
router_fingerprint_is_me(const char *fp)
{
char digest[DIGEST_LEN];
if (strlen(fp) == HEX_DIGEST_LEN &&
base16_decode(digest, sizeof(digest), fp, HEX_DIGEST_LEN) == 0)
return router_digest_is_me(digest);
return 0;
}
/** Return a routerinfo for this OR, rebuilding a fresh one if
* necessary. Return NULL on error, or if called on an OP. */
routerinfo_t *
router_get_my_routerinfo(void)
{
if (!server_mode(get_options()))
return NULL;
if (!desc_routerinfo) {
if (router_rebuild_descriptor(1))
return NULL;
}
return desc_routerinfo;
}
/** OR only: Return a signed server descriptor for this OR, rebuilding a fresh
* one if necessary. Return NULL on error.
*/
const char *
router_get_my_descriptor(void)
{
const char *body;
if (!desc_routerinfo) {
if (router_rebuild_descriptor(1))
return NULL;
}
body = signed_descriptor_get_body(&desc_routerinfo->cache_info);
log_debug(LD_GENERAL,"my desc is '%s'", body);
return body;
}
/*DOCDOC*/
static smartlist_t *warned_nonexistent_family = NULL;
/** If <b>force</b> is true, or our descriptor is out-of-date, rebuild
* a fresh routerinfo and signed server descriptor for this OR.
* Return 0 on success, -1 on error.
*/
int
router_rebuild_descriptor(int force)
{
routerinfo_t *ri;
uint32_t addr;
char platform[256];
int hibernating = we_are_hibernating();
or_options_t *options = get_options();
if (desc_clean_since && !force)
return 0;
if (resolve_my_address(options, &addr, NULL) < 0) {
log_warn(LD_CONFIG,"options->Address didn't resolve into an IP.");
return -1;
}
ri = tor_malloc_zero(sizeof(routerinfo_t));
ri->address = tor_dup_addr(addr);
ri->nickname = tor_strdup(options->Nickname);
ri->addr = addr;
ri->or_port = options->ORPort;
ri->dir_port = options->DirPort;
ri->cache_info.published_on = time(NULL);
ri->onion_pkey = crypto_pk_dup_key(get_onion_key()); /* must invoke from
* main thread */
ri->identity_pkey = crypto_pk_dup_key(get_identity_key());
if (crypto_pk_get_digest(ri->identity_pkey,
ri->cache_info.identity_digest)<0) {
routerinfo_free(ri);
return -1;
}
get_platform_str(platform, sizeof(platform));
ri->platform = tor_strdup(platform);
ri->bandwidthrate = (int)options->BandwidthRate;
ri->bandwidthburst = (int)options->BandwidthBurst;
ri->bandwidthcapacity = hibernating ? 0 : rep_hist_bandwidth_assess();
if (options->BandwidthRate > options->MaxAdvertisedBandwidth)
ri->bandwidthrate = (int)options->MaxAdvertisedBandwidth;
policies_parse_exit_policy(options->ExitPolicy, &ri->exit_policy,
options->ExitPolicyRejectPrivate);
if (desc_routerinfo) { /* inherit values */
ri->is_valid = desc_routerinfo->is_valid;
ri->is_running = desc_routerinfo->is_running;
ri->is_named = desc_routerinfo->is_named;
}
if (authdir_mode(options))
ri->is_valid = ri->is_named = 1; /* believe in yourself */
if (options->MyFamily) {
smartlist_t *family;
if (!warned_nonexistent_family)
warned_nonexistent_family = smartlist_create();
family = smartlist_create();
ri->declared_family = smartlist_create();
smartlist_split_string(family, options->MyFamily, ",",
SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 0);
SMARTLIST_FOREACH(family, char *, name,
{
routerinfo_t *member;
if (!strcasecmp(name, options->Nickname))
member = ri;
else
member = router_get_by_nickname(name, 1);
if (!member) {
if (!smartlist_string_isin(warned_nonexistent_family, name) &&
!is_legal_hexdigest(name)) {
log_warn(LD_CONFIG,
"I have no descriptor for the router named \"%s\" "
"in my declared family; I'll use the nickname as is, but "
"this may confuse clients.", name);
smartlist_add(warned_nonexistent_family, tor_strdup(name));
}
smartlist_add(ri->declared_family, name);
name = NULL;
} else {
char *fp = tor_malloc(HEX_DIGEST_LEN+2);
fp[0] = '$';
base16_encode(fp+1,HEX_DIGEST_LEN+1,
member->cache_info.identity_digest, DIGEST_LEN);
smartlist_add(ri->declared_family, fp);
if (smartlist_string_isin(warned_nonexistent_family, name))
smartlist_string_remove(warned_nonexistent_family, name);
}
tor_free(name);
});
smartlist_free(family);
}
ri->cache_info.signed_descriptor_body = tor_malloc(8192);
if (router_dump_router_to_string(ri->cache_info.signed_descriptor_body, 8192,
ri, get_identity_key())<0) {
log_warn(LD_BUG, "Couldn't allocate string for descriptor.");
return -1;
}
ri->cache_info.signed_descriptor_len =
strlen(ri->cache_info.signed_descriptor_body);
crypto_digest(ri->cache_info.signed_descriptor_digest,
ri->cache_info.signed_descriptor_body,
ri->cache_info.signed_descriptor_len);
if (desc_routerinfo)
routerinfo_free(desc_routerinfo);
desc_routerinfo = ri;
desc_clean_since = time(NULL);
desc_needs_upload = 1;
return 0;
}
/** Mark descriptor out of date if it's older than <b>when</b> */
void
mark_my_descriptor_dirty_if_older_than(time_t when)
{
if (desc_clean_since < when)
mark_my_descriptor_dirty();
}
/** Call when the current descriptor is out of date. */
void
mark_my_descriptor_dirty(void)
{
desc_clean_since = 0;
}
/** How frequently will we republish our descriptor because of large (factor
* of 2) shifts in estimated bandwidth? */
#define MAX_BANDWIDTH_CHANGE_FREQ (20*60)
/** Check whether bandwidth has changed a lot since the last time we announced
* bandwidth. If so, mark our descriptor dirty. */
void
check_descriptor_bandwidth_changed(time_t now)
{
static time_t last_changed = 0;
uint64_t prev, cur;
if (!desc_routerinfo)
return;
prev = desc_routerinfo->bandwidthcapacity;
cur = we_are_hibernating() ? 0 : rep_hist_bandwidth_assess();
if ((prev != cur && (!prev || !cur)) ||
cur > prev*2 ||
cur < prev/2) {
if (last_changed+MAX_BANDWIDTH_CHANGE_FREQ < now) {
log_info(LD_GENERAL,
"Measured bandwidth has changed; rebuilding descriptor.");
mark_my_descriptor_dirty();
last_changed = now;
}
}
}
/** Check whether our own address as defined by the Address configuration
* has changed. This is for routers that get their address from a service
* like dyndns. If our address has changed, mark our descriptor dirty. */
void
check_descriptor_ipaddress_changed(time_t now)
{
uint32_t prev, cur;
or_options_t *options = get_options();
if (!desc_routerinfo)
return;
prev = desc_routerinfo->addr;
if (resolve_my_address(options, &cur, NULL) < 0) {
log_warn(LD_CONFIG,"options->Address didn't resolve into an IP.");
return;
}
if (prev != cur) {
char addrbuf_prev[INET_NTOA_BUF_LEN];
char addrbuf_cur[INET_NTOA_BUF_LEN];
struct in_addr in_prev;
struct in_addr in_cur;
in_prev.s_addr = htonl(prev);
tor_inet_ntoa(&in_prev, addrbuf_prev, sizeof(addrbuf_prev));
in_cur.s_addr = htonl(cur);
tor_inet_ntoa(&in_cur, addrbuf_cur, sizeof(addrbuf_cur));
log_info(LD_GENERAL,
"Our IP Address has changed from %s to %s; "
"rebuilding descriptor.",
addrbuf_prev, addrbuf_cur);
mark_my_descriptor_dirty();
}
}
/** Set <b>platform</b> (max length <b>len</b>) to a NUL-terminated short
* string describing the version of Tor and the operating system we're
* currently running on.
*/
void
get_platform_str(char *platform, size_t len)
{
tor_snprintf(platform, len, "Tor %s on %s",
VERSION, get_uname());
return;
}
/* XXX need to audit this thing and count fenceposts. maybe
* refactor so we don't have to keep asking if we're
* near the end of maxlen?
*/
#define DEBUG_ROUTER_DUMP_ROUTER_TO_STRING
/** OR only: Given a routerinfo for this router, and an identity key to sign
* with, encode the routerinfo as a signed server descriptor and write the
* result into <b>s</b>, using at most <b>maxlen</b> bytes. Return -1 on
* failure, and the number of bytes used on success.
*/
int
router_dump_router_to_string(char *s, size_t maxlen, routerinfo_t *router,
crypto_pk_env_t *ident_key)
{
char *onion_pkey; /* Onion key, PEM-encoded. */
char *identity_pkey; /* Identity key, PEM-encoded. */
char digest[DIGEST_LEN];
char published[ISO_TIME_LEN+1];
char fingerprint[FINGERPRINT_LEN+1];
struct in_addr in;
char addrbuf[INET_NTOA_BUF_LEN];
size_t onion_pkeylen, identity_pkeylen;
size_t written;
int result=0;
addr_policy_t *tmpe;
char *bandwidth_usage;
char *family_line;
#ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING
char *s_tmp, *s_dup;
const char *cp;
routerinfo_t *ri_tmp;
#endif
or_options_t *options = get_options();
/* Make sure the identity key matches the one in the routerinfo. */
if (crypto_pk_cmp_keys(ident_key, router->identity_pkey)) {
log_warn(LD_BUG,"Tried to sign a router with a private key that didn't "
"match router's public key!");
return -1;
}
/* record our fingerprint, so we can include it in the descriptor */
if (crypto_pk_get_fingerprint(router->identity_pkey, fingerprint, 1)<0) {
log_err(LD_BUG,"Error computing fingerprint");
return -1;
}
/* PEM-encode the onion key */
if (crypto_pk_write_public_key_to_string(router->onion_pkey,
&onion_pkey,&onion_pkeylen)<0) {
log_warn(LD_BUG,"write onion_pkey to string failed!");
return -1;
}
/* PEM-encode the identity key key */
if (crypto_pk_write_public_key_to_string(router->identity_pkey,
&identity_pkey,&identity_pkeylen)<0) {
log_warn(LD_BUG,"write identity_pkey to string failed!");
tor_free(onion_pkey);
return -1;
}
/* Encode the publication time. */
format_iso_time(published, router->cache_info.published_on);
/* How busy have we been? */
bandwidth_usage = rep_hist_get_bandwidth_lines();
if (router->declared_family && smartlist_len(router->declared_family)) {
size_t n;
char *s = smartlist_join_strings(router->declared_family, " ", 0, &n);
n += strlen("family ") + 2; /* 1 for \n, 1 for \0. */
family_line = tor_malloc(n);
tor_snprintf(family_line, n, "family %s\n", s);
tor_free(s);
} else {
family_line = tor_strdup("");
}
/* Generate the easy portion of the router descriptor. */
result = tor_snprintf(s, maxlen,
"router %s %s %d 0 %d\n"
"platform %s\n"
"published %s\n"
"opt fingerprint %s\n"
"uptime %ld\n"
"bandwidth %d %d %d\n"
"onion-key\n%s"
"signing-key\n%s%s%s%s",
router->nickname,
router->address,
router->or_port,
decide_to_advertise_dirport(options, router),
router->platform,
published,
fingerprint,
stats_n_seconds_working,
(int) router->bandwidthrate,
(int) router->bandwidthburst,
(int) router->bandwidthcapacity,
onion_pkey, identity_pkey,
family_line, bandwidth_usage,
we_are_hibernating() ? "opt hibernating 1\n" : "");
tor_free(family_line);
tor_free(onion_pkey);
tor_free(identity_pkey);
tor_free(bandwidth_usage);
if (result < 0)
return -1;
/* From now on, we use 'written' to remember the current length of 's'. */
written = result;
if (options->ContactInfo && strlen(options->ContactInfo)) {
result = tor_snprintf(s+written,maxlen-written, "contact %s\n",
options->ContactInfo);
if (result<0)
return -1;
written += result;
}
/* Write the exit policy to the end of 's'. */
for (tmpe=router->exit_policy; tmpe; tmpe=tmpe->next) {
/* Write: "accept 1.2.3.4" */
in.s_addr = htonl(tmpe->addr);
tor_inet_ntoa(&in, addrbuf, sizeof(addrbuf));
result = tor_snprintf(s+written, maxlen-written, "%s %s",
tmpe->policy_type == ADDR_POLICY_ACCEPT ? "accept" : "reject",
tmpe->msk == 0 ? "*" : addrbuf);
if (result < 0)
return -1;
written += result;
if (tmpe->msk != 0xFFFFFFFFu && tmpe->msk != 0) {
int n_bits = addr_mask_get_bits(tmpe->msk);
if (n_bits >= 0) {
if (tor_snprintf(s+written, maxlen-written, "/%d", n_bits)<0)
return -1;
} else {
/* Write "/255.255.0.0" */
in.s_addr = htonl(tmpe->msk);
tor_inet_ntoa(&in, addrbuf, sizeof(addrbuf));
if (tor_snprintf(s+written, maxlen-written, "/%s", addrbuf)<0)
return -1;
}
written += strlen(s+written);
}
if (tmpe->prt_min <= 1 && tmpe->prt_max == 65535) {
/* There is no port set; write ":*" */
if (written+4 > maxlen)
return -1;
strlcat(s+written, ":*\n", maxlen-written);
written += 3;
} else if (tmpe->prt_min == tmpe->prt_max) {
/* There is only one port; write ":80". */
result = tor_snprintf(s+written, maxlen-written, ":%d\n", tmpe->prt_min);
if (result<0)
return -1;
written += result;
} else {
/* There is a range of ports; write ":79-80". */
result = tor_snprintf(s+written, maxlen-written, ":%d-%d\n",
tmpe->prt_min, tmpe->prt_max);
if (result<0)
return -1;
written += result;
}
} /* end for */
if (written+256 > maxlen) /* Not enough room for signature. */
return -1;
/* Sign the directory */
strlcat(s+written, "router-signature\n", maxlen-written);
written += strlen(s+written);
s[written] = '\0';
if (router_get_router_hash(s, digest) < 0)
return -1;
if (router_append_dirobj_signature(s+written,maxlen-written,
digest,ident_key)<0) {
log_warn(LD_BUG, "Couldn't sign router descriptor");
return -1;
}
written += strlen(s+written);
if (written+2 > maxlen)
return -1;
/* include a last '\n' */
s[written] = '\n';
s[written+1] = 0;
#ifdef DEBUG_ROUTER_DUMP_ROUTER_TO_STRING
cp = s_tmp = s_dup = tor_strdup(s);
ri_tmp = router_parse_entry_from_string(cp, NULL);
if (!ri_tmp) {
log_err(LD_BUG,
"We just generated a router descriptor we can't parse: <<%s>>",
s);
return -1;
}
tor_free(s_dup);
routerinfo_free(ri_tmp);
#endif
return written+1;
}
/** Return true iff <b>s</b> is a legally valid server nickname. */
int
is_legal_nickname(const char *s)
{
size_t len;
tor_assert(s);
len = strlen(s);
return len > 0 && len <= MAX_NICKNAME_LEN &&
strspn(s,LEGAL_NICKNAME_CHARACTERS) == len;
}
/** Return true iff <b>s</b> is a legally valid server nickname or
* hex-encoded identity-key digest. */
int
is_legal_nickname_or_hexdigest(const char *s)
{
if (*s!='$')
return is_legal_nickname(s);
else
return is_legal_hexdigest(s);
}
/** Return true iff <b>s</b> is a legally valid hex-encoded identity-key
* digest. */
int
is_legal_hexdigest(const char *s)
{
size_t len;
tor_assert(s);
len = strlen(s);
return (len == HEX_DIGEST_LEN+1 &&
s[0] == '$' &&
strspn(s+1,HEX_CHARACTERS)==len-1);
}
/** Forget that we have issued any router-related warnings, so that we'll
* warn again if we see the same errors. */
void
router_reset_warnings(void)
{
if (warned_nonexistent_family) {
SMARTLIST_FOREACH(warned_nonexistent_family, char *, cp, tor_free(cp));
smartlist_clear(warned_nonexistent_family);
}
}
/** Release all static resources held in router.c */
void
router_free_all(void)
{
if (onionkey)
crypto_free_pk_env(onionkey);
if (lastonionkey)
crypto_free_pk_env(lastonionkey);
if (identitykey)
crypto_free_pk_env(identitykey);
if (key_lock)
tor_mutex_free(key_lock);
if (desc_routerinfo)
routerinfo_free(desc_routerinfo);
if (warned_nonexistent_family) {
SMARTLIST_FOREACH(warned_nonexistent_family, char *, cp, tor_free(cp));
smartlist_free(warned_nonexistent_family);
}
}