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directory.c：源码内容

/* See LICENSE for licensing information */
#include "or.h"
#if defined(EXPORTMALLINFO) && defined(HAVE_MALLOC_H) && defined(HAVE_MALLINFO)
#ifndef OPENBSD
#include <malloc.h>
#endif
#endif
/**
* file directory.c
* brief Code to send and fetch directories and router
* descriptors via HTTP. Directories use dirserv.c to generate the
* results; clients use routers.c to parse them.
**/
/* In-points to directory.c:
*
* - directory_post_to_dirservers(), called from
* router_upload_dir_desc_to_dirservers() in router.c
* upload_service_descriptor() in rendservice.c
* - directory_get_from_dirserver(), called from
* rend_client_refetch_renddesc() in rendclient.c
* run_scheduled_events() in main.c
* do_hup() in main.c
* - connection_dir_process_inbuf(), called from
* connection_process_inbuf() in connection.c
* - connection_dir_finished_flushing(), called from
* connection_finished_flushing() in connection.c
* - connection_dir_finished_connecting(), called from
* connection_finished_connecting() in connection.c
*/
static void directory_send_command(dir_connection_t *conn,
int purpose, int direct, const char *resource,
const char *payload, size_t payload_len,
int supports_conditional_consensus,
time_t if_modified_since);
static int directory_handle_command(dir_connection_t *conn);
static int body_is_plausible(const char *body, size_t body_len, int purpose);
static int purpose_needs_anonymity(uint8_t dir_purpose,
uint8_t router_purpose);
static char *http_get_header(const char *headers, const char *which);
static void http_set_address_origin(const char *headers, connection_t *conn);
static void connection_dir_download_networkstatus_failed(
dir_connection_t *conn, int status_code);
static void connection_dir_download_routerdesc_failed(dir_connection_t *conn);
static void connection_dir_download_cert_failed(
dir_connection_t *conn, int status_code);
static void dir_networkstatus_download_failed(smartlist_t *failed,
int status_code);
static void dir_routerdesc_download_failed(smartlist_t *failed,
int status_code,
int router_purpose,
int was_extrainfo,
int was_descriptor_digests);
static void note_client_request(int purpose, int compressed, size_t bytes);
static int client_likes_consensus(networkstatus_t *v, const char *want_url);
static void directory_initiate_command_rend(const char *address,
const tor_addr_t *addr,
uint16_t or_port,
uint16_t dir_port,
int supports_conditional_consensus,
int supports_begindir,
const char *digest,
uint8_t dir_purpose,
uint8_t router_purpose,
int anonymized_connection,
const char *resource,
const char *payload,
size_t payload_len,
time_t if_modified_since,
const rend_data_t *rend_query);
/********* START VARIABLES **********/
/** How far in the future do we allow a directory server to tell us it is
* before deciding that one of us has the wrong time? */
#define ALLOW_DIRECTORY_TIME_SKEW (30*60)
#define X_ADDRESS_HEADER "X-Your-Address-Is: "
/** HTTP cache control: how long do we tell proxies they can cache each
* kind of document we serve? */
#define FULL_DIR_CACHE_LIFETIME (60*60)
#define RUNNINGROUTERS_CACHE_LIFETIME (20*60)
#define DIRPORTFRONTPAGE_CACHE_LIFETIME (20*60)
#define NETWORKSTATUS_CACHE_LIFETIME (5*60)
#define ROUTERDESC_CACHE_LIFETIME (30*60)
#define ROUTERDESC_BY_DIGEST_CACHE_LIFETIME (48*60*60)
#define ROBOTS_CACHE_LIFETIME (24*60*60)
/********* END VARIABLES ************/
/** Return true iff the directory purpose 'purpose' must use an
* anonymous connection to a directory. */
static int
purpose_needs_anonymity(uint8_t dir_purpose, uint8_t router_purpose)
{
if (get_options()->AllDirActionsPrivate)
return 1;
if (router_purpose == ROUTER_PURPOSE_BRIDGE && has_completed_circuit)
return 1; /* if no circuits yet, we may need this info to bootstrap. */
if (dir_purpose == DIR_PURPOSE_UPLOAD_DIR ||
dir_purpose == DIR_PURPOSE_UPLOAD_VOTE ||
dir_purpose == DIR_PURPOSE_UPLOAD_SIGNATURES ||
dir_purpose == DIR_PURPOSE_FETCH_V2_NETWORKSTATUS ||
dir_purpose == DIR_PURPOSE_FETCH_STATUS_VOTE ||
dir_purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES ||
dir_purpose == DIR_PURPOSE_FETCH_CONSENSUS ||
dir_purpose == DIR_PURPOSE_FETCH_CERTIFICATE ||
dir_purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
dir_purpose == DIR_PURPOSE_FETCH_EXTRAINFO)
return 0;
return 1;
}
/** Return a newly allocated string describing auth. */
char *
authority_type_to_string(authority_type_t auth)
{
char *result;
smartlist_t *lst = smartlist_create();
if (auth & V1_AUTHORITY)
smartlist_add(lst, (void*)"V1");
if (auth & V2_AUTHORITY)
smartlist_add(lst, (void*)"V2");
if (auth & BRIDGE_AUTHORITY)
smartlist_add(lst, (void*)"Bridge");
if (auth & HIDSERV_AUTHORITY)
smartlist_add(lst, (void*)"Hidden service");
if (smartlist_len(lst)) {
result = smartlist_join_strings(lst, ", ", 0, NULL);
} else {
result = tor_strdup("[Not an authority]");
}
smartlist_free(lst);
return result;
}
/** Return a string describing a given directory connection purpose. */
static const char *
dir_conn_purpose_to_string(int purpose)
{
switch (purpose)
{
case DIR_PURPOSE_FETCH_RENDDESC:
return "hidden-service descriptor fetch";
case DIR_PURPOSE_UPLOAD_DIR:
return "server descriptor upload";
case DIR_PURPOSE_UPLOAD_RENDDESC:
return "hidden-service descriptor upload";
case DIR_PURPOSE_UPLOAD_VOTE:
return "server vote upload";
case DIR_PURPOSE_UPLOAD_SIGNATURES:
return "consensus signature upload";
case DIR_PURPOSE_FETCH_V2_NETWORKSTATUS:
return "network-status fetch";
case DIR_PURPOSE_FETCH_SERVERDESC:
return "server descriptor fetch";
case DIR_PURPOSE_FETCH_EXTRAINFO:
return "extra-info fetch";
case DIR_PURPOSE_FETCH_CONSENSUS:
return "consensus network-status fetch";
case DIR_PURPOSE_FETCH_CERTIFICATE:
return "authority cert fetch";
case DIR_PURPOSE_FETCH_STATUS_VOTE:
return "status vote fetch";
case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
return "consensus signature fetch";
case DIR_PURPOSE_FETCH_RENDDESC_V2:
return "hidden-service v2 descriptor fetch";
case DIR_PURPOSE_UPLOAD_RENDDESC_V2:
return "hidden-service v2 descriptor upload";
}
log_warn(LD_BUG, "Called with unknown purpose %d", purpose);
return "(unknown)";
}
/** Return true iff identity_digest is the digest of a router we
* believe to support extrainfo downloads. (If is_authority we do
* additional checking that's only valid for authorities.) */
int
router_supports_extrainfo(const char *identity_digest, int is_authority)
{
routerinfo_t *ri = router_get_by_digest(identity_digest);
if (ri) {
if (ri->caches_extra_info)
return 1;
if (is_authority && ri->platform &&
tor_version_as_new_as(ri->platform, "Tor 0.2.0.0-alpha-dev (r10070)"))
return 1;
}
if (is_authority) {
routerstatus_t *rs = router_get_consensus_status_by_id(identity_digest);
if (rs && rs->version_supports_extrainfo_upload)
return 1;
}
return 0;
}
/** Return true iff any trusted directory authority has accepted our
* server descriptor.
*
* We consider any authority sufficient because waiting for all of
* them means it never happens while any authority is down; we don't
* go for something more complex in the middle (like >1/3 or >1/2 or
* >=1/2) because that doesn't seem necessary yet.
*/
int
directories_have_accepted_server_descriptor(void)
{
smartlist_t *servers = router_get_trusted_dir_servers();
or_options_t *options = get_options();
SMARTLIST_FOREACH(servers, trusted_dir_server_t *, d, {
if ((d->type & options->_PublishServerDescriptor) &&
d->has_accepted_serverdesc) {
return 1;
}
});
return 0;
}
/** Start a connection to every suitable directory authority, using
* connection purpose 'purpose' and uploading the payload 'payload'
* (length 'payload_len'). The purpose should be one of
* 'DIR_PURPOSE_UPLOAD_DIR' or 'DIR_PURPOSE_UPLOAD_RENDDESC'.
*
* type specifies what sort of dir authorities (V1, V2,
* HIDSERV, BRIDGE) we should upload to.
*
* If extrainfo_len is nonzero, the first payload_len bytes of
* payload hold a router descriptor, and the next extrainfo_len
* bytes of payload hold an extra-info document. Upload the descriptor
* to all authorities, and the extra-info document to all authorities that
* support it.
*/
void
directory_post_to_dirservers(uint8_t dir_purpose, uint8_t router_purpose,
authority_type_t type,
const char *payload,
size_t payload_len, size_t extrainfo_len)
{
int post_via_tor;
smartlist_t *dirservers = router_get_trusted_dir_servers();
int found = 0;
tor_assert(dirservers);
/* This tries dirservers which we believe to be down, but ultimately, that's
* harmless, and we may as well err on the side of getting things uploaded.
*/
SMARTLIST_FOREACH_BEGIN(dirservers, trusted_dir_server_t *, ds) {
routerstatus_t *rs = &(ds->fake_status);
size_t upload_len = payload_len;
tor_addr_t ds_addr;
if ((type & ds->type) == 0)
continue;
found = 1; /* at least one authority of this type was listed */
if (dir_purpose == DIR_PURPOSE_UPLOAD_DIR)
ds->has_accepted_serverdesc = 0;
if (extrainfo_len && router_supports_extrainfo(ds->digest, 1)) {
upload_len += extrainfo_len;
log_info(LD_DIR, "Uploading an extrainfo too (length %d)",
(int) extrainfo_len);
}
tor_addr_from_ipv4h(&ds_addr, ds->addr);
post_via_tor = purpose_needs_anonymity(dir_purpose, router_purpose) ||
!fascist_firewall_allows_address_dir(&ds_addr, ds->dir_port);
directory_initiate_command_routerstatus(rs, dir_purpose,
router_purpose,
post_via_tor,
NULL, payload, upload_len, 0);
} SMARTLIST_FOREACH_END(ds);
if (!found) {
char *s = authority_type_to_string(type);
log_warn(LD_DIR, "Publishing server descriptor to directory authorities "
"of type '%s', but no authorities of that type listed!", s);
tor_free(s);
}
}
/** Start a connection to a random running directory server, using
* connection purpose dir_purpose, intending to fetch descriptors
* of purpose router_purpose, and requesting resource.
* Use pds_flags as arguments to router_pick_directory_server()
* or router_pick_trusteddirserver().
*/
void
directory_get_from_dirserver(uint8_t dir_purpose, uint8_t router_purpose,
const char *resource, int pds_flags)
{
routerstatus_t *rs = NULL;
or_options_t *options = get_options();
int prefer_authority = directory_fetches_from_authorities(options);
int get_via_tor = purpose_needs_anonymity(dir_purpose, router_purpose);
authority_type_t type;
time_t if_modified_since = 0;
/* FFFF we could break this switch into its own function, and call
* it elsewhere in directory.c. -RD */
switch (dir_purpose) {
case DIR_PURPOSE_FETCH_EXTRAINFO:
type = EXTRAINFO_CACHE |
(router_purpose == ROUTER_PURPOSE_BRIDGE ? BRIDGE_AUTHORITY :
V2_AUTHORITY);
break;
case DIR_PURPOSE_FETCH_V2_NETWORKSTATUS:
case DIR_PURPOSE_FETCH_SERVERDESC:
type = (router_purpose == ROUTER_PURPOSE_BRIDGE ? BRIDGE_AUTHORITY :
V2_AUTHORITY);
break;
case DIR_PURPOSE_FETCH_RENDDESC:
type = HIDSERV_AUTHORITY;
break;
case DIR_PURPOSE_FETCH_STATUS_VOTE:
case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
type = V3_AUTHORITY;
break;
case DIR_PURPOSE_FETCH_CONSENSUS:
case DIR_PURPOSE_FETCH_CERTIFICATE:
type = V3_AUTHORITY;
break;
default:
log_warn(LD_BUG, "Unexpected purpose %d", (int)dir_purpose);
return;
}
if (DIR_PURPOSE_FETCH_CONSENSUS) {
networkstatus_t *v = networkstatus_get_latest_consensus();
if (v)
if_modified_since = v->valid_after + 180;
}
if (!options->FetchServerDescriptors && type != HIDSERV_AUTHORITY)
return;
if (!get_via_tor) {
if (options->UseBridges && type != BRIDGE_AUTHORITY) {
/* want to ask a running bridge for which we have a descriptor. */
/* XXX022 we assume that all of our bridges can answer any
* possible directory question. This won't be true forever. -RD */
/* It certainly is not true with conditional consensus downloading,
* so, for now, never assume the server supports that. */
routerinfo_t *ri = choose_random_entry(NULL);
if (ri) {
tor_addr_t addr;
tor_addr_from_ipv4h(&addr, ri->addr);
directory_initiate_command(ri->address, &addr,
ri->or_port, 0,
0, /* don't use conditional consensus url */
1, ri->cache_info.identity_digest,
dir_purpose,
router_purpose,
0, resource, NULL, 0, if_modified_since);
} else
log_notice(LD_DIR, "Ignoring directory request, since no bridge "
"nodes are available yet.");
return;
} else {
if (prefer_authority || type == BRIDGE_AUTHORITY) {
/* only ask authdirservers, and don't ask myself */
rs = router_pick_trusteddirserver(type, pds_flags);
if (rs == NULL && (pds_flags & PDS_NO_EXISTING_SERVERDESC_FETCH)) {
/* We don't want to fetch from any authorities that we're currently
* fetching server descriptors from, and we got no match. Did we
* get no match because all the authorities have connections
* fetching server descriptors (in which case we should just
* return,) or because all the authorities are down or on fire or
* unreachable or something (in which case we should go on with
* our fallback code)? */
pds_flags &= ~PDS_NO_EXISTING_SERVERDESC_FETCH;
rs = router_pick_trusteddirserver(type, pds_flags);
if (rs) {
log_debug(LD_DIR, "Deferring serverdesc fetch: all authorities "
"are in use.");
return;
}
}
}
if (!rs && type != BRIDGE_AUTHORITY) {
/* anybody with a non-zero dirport will do */
rs = router_pick_directory_server(type, pds_flags);
if (!rs) {
log_info(LD_DIR, "No router found for %s; falling back to "
"dirserver list.", dir_conn_purpose_to_string(dir_purpose));
rs = router_pick_trusteddirserver(type, pds_flags);
if (!rs)
get_via_tor = 1; /* last resort: try routing it via Tor */
}
}
}
} else { /* get_via_tor */
/* Never use fascistfirewall; we're going via Tor. */
if (dir_purpose == DIR_PURPOSE_FETCH_RENDDESC) {
/* only ask hidserv authorities, any of them will do */
pds_flags |= PDS_IGNORE_FASCISTFIREWALL|PDS_ALLOW_SELF;
rs = router_pick_trusteddirserver(HIDSERV_AUTHORITY, pds_flags);
} else {
/* anybody with a non-zero dirport will do. Disregard firewalls. */
pds_flags |= PDS_IGNORE_FASCISTFIREWALL;
rs = router_pick_directory_server(type, pds_flags);
/* If we have any hope of building an indirect conn, we know some router
* descriptors. If (rs==NULL), we can't build circuits anyway, so
* there's no point in falling back to the authorities in this case. */
}
}
if (rs)
directory_initiate_command_routerstatus(rs, dir_purpose,
router_purpose,
get_via_tor,
resource, NULL, 0,
if_modified_since);
else {
log_notice(LD_DIR,
"While fetching directory info, "
"no running dirservers known. Will try again later. "
"(purpose %d)", dir_purpose);
if (!purpose_needs_anonymity(dir_purpose, router_purpose)) {
/* remember we tried them all and failed. */
directory_all_unreachable(time(NULL));
}
}
}
/** As directory_get_from_dirserver, but initiates a request to every
* directory authority other than ourself. Only for use by authorities when
* searching for missing information while voting. */
void
directory_get_from_all_authorities(uint8_t dir_purpose,
uint8_t router_purpose,
const char *resource)
{
tor_assert(dir_purpose == DIR_PURPOSE_FETCH_STATUS_VOTE ||
dir_purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES);
SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
trusted_dir_server_t *, ds,
{
routerstatus_t *rs;
if (router_digest_is_me(ds->digest))
continue;
if (!(ds->type & V3_AUTHORITY))
continue;
rs = &ds->fake_status;
directory_initiate_command_routerstatus(rs, dir_purpose, router_purpose,
0, resource, NULL, 0, 0);
});
}
/** Same as directory_initiate_command_routerstatus(), but accepts
* rendezvous data to fetch a hidden service descriptor. */
void
directory_initiate_command_routerstatus_rend(routerstatus_t *status,
uint8_t dir_purpose,
uint8_t router_purpose,
int anonymized_connection,
const char *resource,
const char *payload,
size_t payload_len,
time_t if_modified_since,
const rend_data_t *rend_query)
{
routerinfo_t *router;
char address_buf[INET_NTOA_BUF_LEN+1];
struct in_addr in;
const char *address;
tor_addr_t addr;
router = router_get_by_digest(status->identity_digest);
if (!router && anonymized_connection) {
log_info(LD_DIR, "Not sending anonymized request to directory '%s'; we "
"don't have its router descriptor.", status->nickname);
return;
} else if (router) {
address = router->address;
} else {
in.s_addr = htonl(status->addr);
tor_inet_ntoa(&in, address_buf, sizeof(address_buf));
address = address_buf;
}
tor_addr_from_ipv4h(&addr, status->addr);
directory_initiate_command_rend(address, &addr,
status->or_port, status->dir_port,
status->version_supports_conditional_consensus,
status->version_supports_begindir,
status->identity_digest,
dir_purpose, router_purpose,
anonymized_connection, resource,
payload, payload_len, if_modified_since,
rend_query);
}
/** Launch a new connection to the directory server status to
* upload or download a server or rendezvous
* descriptor. dir_purpose determines what
* kind of directory connection we're launching, and must be one of
* DIR_PURPOSE_{FETCH|UPLOAD}_{DIR|RENDDESC|RENDDESC_V2}. router_purpose
* specifies the descriptor purposes we have in mind (currently only
* used for FETCH_DIR).
*
* When uploading, payload and payload_len determine the content
* of the HTTP post. Otherwise, payload should be NULL.
*
* When fetching a rendezvous descriptor, resource is the service ID we
* want to fetch.
*/
void
directory_initiate_command_routerstatus(routerstatus_t *status,
uint8_t dir_purpose,
uint8_t router_purpose,
int anonymized_connection,
const char *resource,
const char *payload,
size_t payload_len,
time_t if_modified_since)
{
directory_initiate_command_routerstatus_rend(status, dir_purpose,
router_purpose,
anonymized_connection, resource,
payload, payload_len,
if_modified_since, NULL);
}
/** Return true iff conn is the client side of a directory connection
* we launched to ourself in order to determine the reachability of our
* dir_port. */
static int
directory_conn_is_self_reachability_test(dir_connection_t *conn)
{
if (conn->requested_resource &&
!strcmpstart(conn->requested_resource,"authority")) {
routerinfo_t *me = router_get_my_routerinfo();
if (me &&
router_digest_is_me(conn->identity_digest) &&
tor_addr_eq_ipv4h(&conn->_base.addr, me->addr) && /*XXXX prop 118*/
me->dir_port == conn->_base.port)
return 1;
}
return 0;
}
/** Called when we are unable to complete the client's request to a directory
* server due to a network error: Mark the router as down and try again if
* possible.
*/
void
connection_dir_request_failed(dir_connection_t *conn)
{
if (directory_conn_is_self_reachability_test(conn)) {
return; /* this was a test fetch. don't retry. */
}
if (entry_list_can_grow(get_options()))
router_set_status(conn->identity_digest, 0); /* don't try him again */
if (conn->_base.purpose == DIR_PURPOSE_FETCH_V2_NETWORKSTATUS) {
log_info(LD_DIR, "Giving up on directory server at '%s'; retrying",
conn->_base.address);
connection_dir_download_networkstatus_failed(conn, -1);
} else if (conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
conn->_base.purpose == DIR_PURPOSE_FETCH_EXTRAINFO) {
log_info(LD_DIR, "Giving up on directory server at '%s'; retrying",
conn->_base.address);
connection_dir_download_routerdesc_failed(conn);
} else if (conn->_base.purpose == DIR_PURPOSE_FETCH_CONSENSUS) {
networkstatus_consensus_download_failed(0);
} else if (conn->_base.purpose == DIR_PURPOSE_FETCH_CERTIFICATE) {
log_info(LD_DIR, "Giving up on directory server at '%s'; retrying",
conn->_base.address);
connection_dir_download_cert_failed(conn, 0);
} else if (conn->_base.purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES) {
log_info(LD_DIR, "Giving up downloading detached signatures from '%s'",
conn->_base.address);
} else if (conn->_base.purpose == DIR_PURPOSE_FETCH_STATUS_VOTE) {
log_info(LD_DIR, "Giving up downloading votes from '%s'",
conn->_base.address);
}
}
/** Called when an attempt to download one or more network status
* documents on connection conn failed. Decide whether to
* retry the fetch now, later, or never.
*/
static void
connection_dir_download_networkstatus_failed(dir_connection_t *conn,
int status_code)
{
if (!conn->requested_resource) {
/* We never reached directory_send_command, which means that we never
* opened a network connection. Either we're out of sockets, or the
* network is down. Either way, retrying would be pointless. */
return;
}
if (!strcmpstart(conn->requested_resource, "all")) {
/* We're a non-authoritative directory cache; try again. Ignore status
* code, since we don't want to keep trying forever in a tight loop
* if all the authorities are shutting us out. */
smartlist_t *trusted_dirs = router_get_trusted_dir_servers();
SMARTLIST_FOREACH(trusted_dirs, trusted_dir_server_t *, ds,
download_status_failed(&ds->v2_ns_dl_status, 0));
directory_get_from_dirserver(conn->_base.purpose, conn->router_purpose,
"all.z", 0 /* don't retry_if_no_servers */);
} else if (!strcmpstart(conn->requested_resource, "fp/")) {
/* We were trying to download by fingerprint; mark them all as having
* failed, and possibly retry them later.*/
smartlist_t *failed = smartlist_create();
dir_split_resource_into_fingerprints(conn->requested_resource+3,
failed, NULL, 0, 0);
if (smartlist_len(failed)) {
dir_networkstatus_download_failed(failed, status_code);
SMARTLIST_FOREACH(failed, char *, cp, tor_free(cp));
}
smartlist_free(failed);
}
}
/** Called when an attempt to download one or more router descriptors
* or extra-info documents on connection conn failed.
*/
static void
connection_dir_download_routerdesc_failed(dir_connection_t *conn)
{
/* No need to increment the failure count for routerdescs, since
* it's not their fault. */
/* No need to relaunch descriptor downloads here: we already do it
* every 10 or 60 seconds (FOO_DESCRIPTOR_RETRY_INTERVAL) in main.c. */
tor_assert(conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
conn->_base.purpose == DIR_PURPOSE_FETCH_EXTRAINFO);
(void) conn;
}
/** Called when an attempt to fetch a certificate fails. */
static void
connection_dir_download_cert_failed(dir_connection_t *conn, int status)
{
smartlist_t *failed;
tor_assert(conn->_base.purpose == DIR_PURPOSE_FETCH_CERTIFICATE);
if (!conn->requested_resource)
return;
failed = smartlist_create();
dir_split_resource_into_fingerprints(conn->requested_resource+3,
failed, NULL, 1, 0);
SMARTLIST_FOREACH(failed, char *, cp,
{
authority_cert_dl_failed(cp, status);
tor_free(cp);
});
smartlist_free(failed);
update_certificate_downloads(time(NULL));
}
/** Evaluate the situation and decide if we should use an encrypted
* "begindir-style" connection for this directory request.
* 1) If or_port is 0, or it's a direct conn and or_port is firewalled
* or we're a dir mirror, no.
* 2) If we prefer to avoid begindir conns, and we're not fetching or
* publishing a bridge relay descriptor, no.
* 3) Else yes.
*/
static int
directory_command_should_use_begindir(or_options_t *options,
const tor_addr_t *addr,
int or_port, uint8_t router_purpose,
int anonymized_connection)
{
if (!or_port)
return 0; /* We don't know an ORPort -- no chance. */
if (!anonymized_connection)
if (!fascist_firewall_allows_address_or(addr, or_port) ||
directory_fetches_from_authorities(options) ||
(server_mode(options) && !options->Address))
return 0; /* We're firewalled or are acting like a relay -- also no. */
if (!options->TunnelDirConns &&
router_purpose != ROUTER_PURPOSE_BRIDGE)
return 0; /* We prefer to avoid using begindir conns. Fine. */
return 1;
}
/** Helper for directory_initiate_command_routerstatus: send the
* command to a server whose address is address, whose IP is
* addr, whose directory port is dir_port, whose tor version
* supports_begindir, and whose identity key digest is
* digest. */
void
directory_initiate_command(const char *address, const tor_addr_t *_addr,
uint16_t or_port, uint16_t dir_port,
int supports_conditional_consensus,
int supports_begindir, const char *digest,
uint8_t dir_purpose, uint8_t router_purpose,
int anonymized_connection, const char *resource,
const char *payload, size_t payload_len,
time_t if_modified_since)
{
directory_initiate_command_rend(address, _addr, or_port, dir_port,
supports_conditional_consensus,
supports_begindir, digest, dir_purpose,
router_purpose, anonymized_connection,
resource, payload, payload_len,
if_modified_since, NULL);
}
/** Same as directory_initiate_command(), but accepts rendezvous data to
* fetch a hidden service descriptor. */
static void
directory_initiate_command_rend(const char *address, const tor_addr_t *_addr,
uint16_t or_port, uint16_t dir_port,
int supports_conditional_consensus,
int supports_begindir, const char *digest,
uint8_t dir_purpose, uint8_t router_purpose,
int anonymized_connection,
const char *resource,
const char *payload, size_t payload_len,
time_t if_modified_since,
const rend_data_t *rend_query)
{
dir_connection_t *conn;
or_options_t *options = get_options();
int socket_error = 0;
int use_begindir = supports_begindir &&
directory_command_should_use_begindir(options, _addr,
or_port, router_purpose, anonymized_connection);
tor_addr_t addr;
tor_assert(address);
tor_assert(_addr);
tor_assert(or_port || dir_port);
tor_assert(digest);
tor_addr_copy(&addr, _addr);
log_debug(LD_DIR, "anonymized %d, use_begindir %d.",
anonymized_connection, use_begindir);
log_debug(LD_DIR, "Initiating %s", dir_conn_purpose_to_string(dir_purpose));
conn = dir_connection_new(AF_INET);
/* set up conn so it's got all the data we need to remember */
tor_addr_copy(&conn->_base.addr, &addr);
conn->_base.port = use_begindir ? or_port : dir_port;
conn->_base.address = tor_strdup(address);
memcpy(conn->identity_digest, digest, DIGEST_LEN);
conn->_base.purpose = dir_purpose;
conn->router_purpose = router_purpose;
/* give it an initial state */
conn->_base.state = DIR_CONN_STATE_CONNECTING;
/* decide whether we can learn our IP address from this conn */
conn->dirconn_direct = !anonymized_connection;
/* copy rendezvous data, if any */
if (rend_query)
conn->rend_data = rend_data_dup(rend_query);
if (!anonymized_connection && !use_begindir) {
/* then we want to connect to dirport directly */
if (options->HttpProxy) {
tor_addr_from_ipv4h(&addr, options->HttpProxyAddr);
dir_port = options->HttpProxyPort;
}
switch (connection_connect(TO_CONN(conn), conn->_base.address, &addr,
dir_port, &socket_error)) {
case -1:
connection_dir_request_failed(conn); /* retry if we want */
/* XXX we only pass 'conn' above, not 'resource', 'payload',
* etc. So in many situations it can't retry! -RD */
connection_free(TO_CONN(conn));
return;
case 1:
/* start flushing conn */
conn->_base.state = DIR_CONN_STATE_CLIENT_SENDING;
/* fall through */
case 0:
/* queue the command on the outbuf */
directory_send_command(conn, dir_purpose, 1, resource,
payload, payload_len,
supports_conditional_consensus,
if_modified_since);
connection_watch_events(TO_CONN(conn), EV_READ | EV_WRITE);
/* writable indicates finish, readable indicates broken link,
error indicates broken link in windowsland. */
}
} else { /* we want to connect via a tor connection */
edge_connection_t *linked_conn;
/* If it's an anonymized connection, remember the fact that we
* wanted it for later: maybe we'll want it again soon. */
if (anonymized_connection && use_begindir)
rep_hist_note_used_internal(time(NULL), 0, 1);
else if (anonymized_connection && !use_begindir)
rep_hist_note_used_port(time(NULL), conn->_base.port);
/* make an AP connection
* populate it and add it at the right state
* hook up both sides
*/
linked_conn =
connection_ap_make_link(conn->_base.address, conn->_base.port,
digest, use_begindir, conn->dirconn_direct);
if (!linked_conn) {
log_warn(LD_NET,"Making tunnel to dirserver failed.");
connection_mark_for_close(TO_CONN(conn));
return;
}
connection_link_connections(TO_CONN(conn), TO_CONN(linked_conn));
if (connection_add(TO_CONN(conn)) < 0) {
log_warn(LD_NET,"Unable to add connection for link to dirserver.");
connection_mark_for_close(TO_CONN(conn));
return;
}
conn->_base.state = DIR_CONN_STATE_CLIENT_SENDING;
/* queue the command on the outbuf */
directory_send_command(conn, dir_purpose, 0, resource,
payload, payload_len,
supports_conditional_consensus,
if_modified_since);
connection_watch_events(TO_CONN(conn), EV_READ | EV_WRITE);
connection_start_reading(TO_CONN(linked_conn));
}
}
/** Return true iff anything we say on conn is being encrypted before
* we send it to the client/server. */
int
connection_dir_is_encrypted(dir_connection_t *conn)
{
/* Right now it's sufficient to see if conn is or has been linked, since
* the only thing it could be linked to is an edge connection on a
* circuit, and the only way it could have been unlinked is at the edge
* connection getting closed.
*/
return TO_CONN(conn)->linked;
}
/** Helper for sorting
*
* sort strings alphabetically
*/
static int
_compare_strs(const void **a, const void **b)
{
const char *s1 = *a, *s2 = *b;
return strcmp(s1, s2);
}
#define CONDITIONAL_CONSENSUS_FPR_LEN 3
#if (CONDITIONAL_CONSENSUS_FPR_LEN > DIGEST_LEN)
#error "conditional consensus fingerprint length is larger than digest length"
#endif
/** Return the URL we should use for a consensus download.
*
* This url depends on whether or not the server we go to
* is sufficiently new to support conditional consensus downloading,
* i.e. GET .../consensus/fpr+fpr+fpr
*/
static char *
directory_get_consensus_url(int supports_conditional_consensus)
{
char *url;
size_t len;
if (supports_conditional_consensus) {
char *authority_id_list;
smartlist_t *authority_digets = smartlist_create();
SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
trusted_dir_server_t *, ds,
{
char *hex;
if (!(ds->type & V3_AUTHORITY))
continue;
hex = tor_malloc(2*CONDITIONAL_CONSENSUS_FPR_LEN+1);
base16_encode(hex, 2*CONDITIONAL_CONSENSUS_FPR_LEN+1,
ds->v3_identity_digest, CONDITIONAL_CONSENSUS_FPR_LEN);
smartlist_add(authority_digets, hex);
});
smartlist_sort(authority_digets, _compare_strs);
authority_id_list = smartlist_join_strings(authority_digets,
"+", 0, NULL);
len = strlen(authority_id_list)+64;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/status-vote/current/consensus/%s.z",
authority_id_list);
SMARTLIST_FOREACH(authority_digets, char *, cp, tor_free(cp));
smartlist_free(authority_digets);
tor_free(authority_id_list);
} else {
url = tor_strdup("/tor/status-vote/current/consensus.z");
}
return url;
}
/** Queue an appropriate HTTP command on conn->outbuf. The other args
* are as in directory_initiate_command.
*/
static void
directory_send_command(dir_connection_t *conn,
int purpose, int direct, const char *resource,
const char *payload, size_t payload_len,
int supports_conditional_consensus,
time_t if_modified_since)
{
char proxystring[256];
char proxyauthstring[256];
char hoststring[128];
char imsstring[RFC1123_TIME_LEN+32];
char *url;
char request[8192];
const char *httpcommand = NULL;
size_t len;
tor_assert(conn);
tor_assert(conn->_base.type == CONN_TYPE_DIR);
tor_free(conn->requested_resource);
if (resource)
conn->requested_resource = tor_strdup(resource);
/* come up with a string for which Host: we want */
if (conn->_base.port == 80) {
strlcpy(hoststring, conn->_base.address, sizeof(hoststring));
} else {
tor_snprintf(hoststring, sizeof(hoststring),"%s:%d",
conn->_base.address, conn->_base.port);
}
/* Format if-modified-since */
if (!if_modified_since) {
imsstring[0] = '';
} else {
char b[RFC1123_TIME_LEN+1];
format_rfc1123_time(b, if_modified_since);
tor_snprintf(imsstring, sizeof(imsstring), "rnIf-Modified-Since: %s", b);
}
/* come up with some proxy lines, if we're using one. */
if (direct && get_options()->HttpProxy) {
char *base64_authenticator=NULL;
const char *authenticator = get_options()->HttpProxyAuthenticator;
tor_snprintf(proxystring, sizeof(proxystring),"http://%s", hoststring);
if (authenticator) {
base64_authenticator = alloc_http_authenticator(authenticator);
if (!base64_authenticator)
log_warn(LD_BUG, "Encoding http authenticator failed");
}
if (base64_authenticator) {
tor_snprintf(proxyauthstring, sizeof(proxyauthstring),
"rnProxy-Authorization: Basic %s",
base64_authenticator);
tor_free(base64_authenticator);
} else {
proxyauthstring[0] = 0;
}
} else {
proxystring[0] = 0;
proxyauthstring[0] = 0;
}
switch (purpose) {
case DIR_PURPOSE_FETCH_V2_NETWORKSTATUS:
tor_assert(resource);
httpcommand = "GET";
len = strlen(resource)+32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/status/%s", resource);
break;
case DIR_PURPOSE_FETCH_CONSENSUS:
tor_assert(!resource);
tor_assert(!payload);
httpcommand = "GET";
url = directory_get_consensus_url(supports_conditional_consensus);
log_info(LD_DIR, "Downloading consensus from %s using %s",
hoststring, url);
break;
case DIR_PURPOSE_FETCH_CERTIFICATE:
tor_assert(resource);
tor_assert(!payload);
httpcommand = "GET";
len = strlen(resource)+32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/keys/%s", resource);
break;
case DIR_PURPOSE_FETCH_STATUS_VOTE:
tor_assert(resource);
tor_assert(!payload);
httpcommand = "GET";
len = strlen(resource)+32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/status-vote/next/%s.z", resource);
break;
case DIR_PURPOSE_FETCH_DETACHED_SIGNATURES:
tor_assert(!resource);
tor_assert(!payload);
httpcommand = "GET";
url = tor_strdup("/tor/status-vote/next/consensus-signatures.z");
break;
case DIR_PURPOSE_FETCH_SERVERDESC:
tor_assert(resource);
httpcommand = "GET";
len = strlen(resource)+32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/server/%s", resource);
break;
case DIR_PURPOSE_FETCH_EXTRAINFO:
tor_assert(resource);
httpcommand = "GET";
len = strlen(resource)+32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/extra/%s", resource);
break;
case DIR_PURPOSE_UPLOAD_DIR:
tor_assert(!resource);
tor_assert(payload);
httpcommand = "POST";
url = tor_strdup("/tor/");
break;
case DIR_PURPOSE_UPLOAD_VOTE:
tor_assert(!resource);
tor_assert(payload);
httpcommand = "POST";
url = tor_strdup("/tor/post/vote");
break;
case DIR_PURPOSE_UPLOAD_SIGNATURES:
tor_assert(!resource);
tor_assert(payload);
httpcommand = "POST";
url = tor_strdup("/tor/post/consensus-signature");
break;
case DIR_PURPOSE_FETCH_RENDDESC:
tor_assert(resource);
tor_assert(!payload);
/* this must be true or we wouldn't be doing the lookup */
tor_assert(strlen(resource) <= REND_SERVICE_ID_LEN_BASE32);
/* This breaks the function abstraction. */
conn->rend_data = tor_malloc_zero(sizeof(rend_data_t));
strlcpy(conn->rend_data->onion_address, resource,
sizeof(conn->rend_data->onion_address));
conn->rend_data->rend_desc_version = 0;
httpcommand = "GET";
/* Request the most recent versioned descriptor. */
// (XXXX We were going to switch this to fetch rendezvous1 descriptors,
// but that never got testing, and it wasn't a good design.)
len = strlen(resource)+32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/rendezvous/%s", resource);
break;
case DIR_PURPOSE_FETCH_RENDDESC_V2:
tor_assert(resource);
tor_assert(strlen(resource) <= REND_DESC_ID_V2_LEN_BASE32);
tor_assert(!payload);
conn->rend_data->rend_desc_version = 2;
httpcommand = "GET";
len = strlen(resource) + 32;
url = tor_malloc(len);
tor_snprintf(url, len, "/tor/rendezvous2/%s", resource);
break;
case DIR_PURPOSE_UPLOAD_RENDDESC:
tor_assert(!resource);
tor_assert(payload);
httpcommand = "POST";
url = tor_strdup("/tor/rendezvous/publish");
break;
case DIR_PURPOSE_UPLOAD_RENDDESC_V2:
tor_assert(!resource);
tor_assert(payload);
httpcommand = "POST";
url = tor_strdup("/tor/rendezvous2/publish");
break;
default:
tor_assert(0);
return;
}
if (strlen(proxystring) + strlen(url) >= 4096) {
log_warn(LD_BUG,
"Squid does not like URLs longer than 4095 bytes, and this "
"one is %d bytes long: %s%s",
(int)(strlen(proxystring) + strlen(url)), proxystring, url);
}
tor_snprintf(request, sizeof(request), "%s %s", httpcommand, proxystring);
connection_write_to_buf(request, strlen(request), TO_CONN(conn));
connection_write_to_buf(url, strlen(url), TO_CONN(conn));
tor_free(url);
if (!strcmp(httpcommand, "GET") && !payload) {
tor_snprintf(request, sizeof(request),
" HTTP/1.0rnHost: %s%s%srnrn",
hoststring,
imsstring,
proxyauthstring);
} else {
tor_snprintf(request, sizeof(request),
" HTTP/1.0rnContent-Length: %lurnHost: %s%s%srnrn",
payload ? (unsigned long)payload_len : 0,
hoststring,
imsstring,
proxyauthstring);
}
connection_write_to_buf(request, strlen(request), TO_CONN(conn));
if (payload) {
/* then send the payload afterwards too */
connection_write_to_buf(payload, payload_len, TO_CONN(conn));
}
}
/** Parse an HTTP request string headers of the form
* verbatim
* "%s [http[s]://]%s HTTP/1..."
* endverbatim
* If it's well-formed, strdup the second %s into *url, and
* nul-terminate it. If the url doesn't start with "/tor/", rewrite it
* so it does. Return 0.
* Otherwise, return -1.
*/
static int
parse_http_url(const char *headers, char **url)
{
char *s, *start, *tmp;
s = (char *)eat_whitespace_no_nl(headers);
if (!*s) return -1;
s = (char *)find_whitespace(s); /* get past GET/POST */
if (!*s) return -1;
s = (char *)eat_whitespace_no_nl(s);
if (!*s) return -1;
start = s; /* this is it, assuming it's valid */
s = (char *)find_whitespace(start);
if (!*s) return -1;
/* tolerate the http[s] proxy style of putting the hostname in the url */
if (s-start >= 4 && !strcmpstart(start,"http")) {
tmp = start + 4;
if (*tmp == 's')
tmp++;
if (s-tmp >= 3 && !strcmpstart(tmp,"://")) {
tmp = strchr(tmp+3, '/');
if (tmp && tmp < s) {
log_debug(LD_DIR,"Skipping over 'http[s]://hostname' string");
start = tmp;
}
}
}
if (s-start < 5 || strcmpstart(start,"/tor/")) { /* need to rewrite it */
*url = tor_malloc(s - start + 5);
strlcpy(*url,"/tor", s-start+5);
strlcat((*url)+4, start, s-start+1);
} else {
*url = tor_strndup(start, s-start);
}
return 0;
}
/** Return a copy of the first HTTP header in headers whose key is
* which. The key should be given with a terminating colon and space;
* this function copies everything after, up to but not including the
* following \r\n. */
static char *
http_get_header(const char *headers, const char *which)
{
const char *cp = headers;
while (cp) {
if (!strcasecmpstart(cp, which)) {
char *eos;
cp += strlen(which);
if ((eos = strchr(cp,'r')))
return tor_strndup(cp, eos-cp);
else
return tor_strdup(cp);
}
cp = strchr(cp, 'n');
if (cp)
++cp;
}
return NULL;
}
/** If headers indicates that a proxy was involved, then rewrite
* conn->address to describe our best guess of the address that
* originated this HTTP request. */
static void
http_set_address_origin(const char *headers, connection_t *conn)
{
char *fwd;
fwd = http_get_header(headers, "Forwarded-For: ");
if (!fwd)
fwd = http_get_header(headers, "X-Forwarded-For: ");
if (fwd) {
struct in_addr in;
if (!tor_inet_aton(fwd, &in) || is_internal_IP(ntohl(in.s_addr), 0)) {
log_debug(LD_DIR, "Ignoring unrecognized or internal IP %s",
escaped(fwd));
tor_free(fwd);
return;
}
tor_free(conn->address);
conn->address = tor_strdup(fwd);
tor_free(fwd);
}
}
/** Parse an HTTP response string headers of the form
* verbatim
* "HTTP/1.%d %d%srn...".
* endverbatim
*
* If it's well-formed, assign the status code to *code and
* return 0. Otherwise, return -1.
*
* On success: If date is provided, set *date to the Date
* header in the http headers, or 0 if no such header is found. If
* compression is provided, set *compression to the
* compression method given in the Content-Encoding header, or 0 if no
* such header is found, or -1 if the value of the header is not
* recognized. If reason is provided, strdup the reason string
* into it.
*/
int
parse_http_response(const char *headers, int *code, time_t *date,
compress_method_t *compression, char **reason)
{
unsigned n1, n2;
char datestr[RFC1123_TIME_LEN+1];
smartlist_t *parsed_headers;
tor_assert(headers);
tor_assert(code);
while (TOR_ISSPACE(*headers)) headers++; /* tolerate leading whitespace */
if (tor_sscanf(headers, "HTTP/1.%u %u", &n1, &n2) < 2 ||
(n1 != 0 && n1 != 1) ||
(n2 < 100 || n2 >= 600)) {
log_warn(LD_HTTP,"Failed to parse header %s",escaped(headers));
return -1;
}
*code = n2;
parsed_headers = smartlist_create();
smartlist_split_string(parsed_headers, headers, "n",
SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, -1);
if (reason) {
smartlist_t *status_line_elements = smartlist_create();
tor_assert(smartlist_len(parsed_headers));
smartlist_split_string(status_line_elements,
smartlist_get(parsed_headers, 0),
" ", SPLIT_SKIP_SPACE|SPLIT_IGNORE_BLANK, 3);
tor_assert(smartlist_len(status_line_elements) <= 3);
if (smartlist_len(status_line_elements) == 3) {
*reason = smartlist_get(status_line_elements, 2);
smartlist_set(status_line_elements, 2, NULL); /* Prevent free */
}
SMARTLIST_FOREACH(status_line_elements, char *, cp, tor_free(cp));
smartlist_free(status_line_elements);
}
if (date) {
*date = 0;
SMARTLIST_FOREACH(parsed_headers, const char *, s,
if (!strcmpstart(s, "Date: ")) {
strlcpy(datestr, s+6, sizeof(datestr));
/* This will do nothing on failure, so we don't need to check
the result. We shouldn't warn, since there are many other valid
date formats besides the one we use. */
parse_rfc1123_time(datestr, date);
break;
});
}
if (compression) {
const char *enc = NULL;
SMARTLIST_FOREACH(parsed_headers, const char *, s,
if (!strcmpstart(s, "Content-Encoding: ")) {
enc = s+18; break;
});
if (!enc || !strcmp(enc, "identity")) {
*compression = NO_METHOD;
} else if (!strcmp(enc, "deflate") || !strcmp(enc, "x-deflate")) {
*compression = ZLIB_METHOD;
} else if (!strcmp(enc, "gzip") || !strcmp(enc, "x-gzip")) {
*compression = GZIP_METHOD;
} else {
log_info(LD_HTTP, "Unrecognized content encoding: %s. Trying to deal.",
escaped(enc));
*compression = UNKNOWN_METHOD;
}
}
SMARTLIST_FOREACH(parsed_headers, char *, s, tor_free(s));
smartlist_free(parsed_headers);
return 0;
}
/** Return true iff body doesn't start with a plausible router or
* running-list or directory opening. This is a sign of possible compression.
**/
static int
body_is_plausible(const char *body, size_t len, int purpose)
{
int i;
if (len == 0)
return 1; /* empty bodies don't need decompression */
if (len < 32)
return 0;
if (purpose != DIR_PURPOSE_FETCH_RENDDESC) {
if (!strcmpstart(body,"router") ||
!strcmpstart(body,"signed-directory") ||
!strcmpstart(body,"network-status") ||
!strcmpstart(body,"running-routers"))
return 1;
for (i=0;i<32;++i) {
if (!TOR_ISPRINT(body[i]) && !TOR_ISSPACE(body[i]))
return 0;
}
return 1;
} else {
return 1;
}
}
/** Called when we've just fetched a bunch of router descriptors in
* body. The list which, if present, holds digests for
* descriptors we requested: descriptor digests if descriptor_digests
* is true, or identity digests otherwise. Parse the descriptors, validate
* them, and annotate them as having purpose purpose and as having been
* downloaded from source.
*
* Return the number of routers actually added. */
static int
load_downloaded_routers(const char *body, smartlist_t *which,
int descriptor_digests,
int router_purpose,
const char *source)
{
char buf[256];
char time_buf[ISO_TIME_LEN+1];
int added = 0;
int general = router_purpose == ROUTER_PURPOSE_GENERAL;
format_iso_time(time_buf, time(NULL));
tor_assert(source);
if (tor_snprintf(buf, sizeof(buf),
"@downloaded-at %sn"
"@source %sn"
"%s%s%s", time_buf, escaped(source),
!general ? "@purpose " : "",
!general ? router_purpose_to_string(router_purpose) : "",
!general ? "n" : "")<0)
return added;
added = router_load_routers_from_string(body, NULL, SAVED_NOWHERE, which,
descriptor_digests, buf);
control_event_bootstrap(BOOTSTRAP_STATUS_LOADING_DESCRIPTORS,
count_loading_descriptors_progress());
return added;
}
/** We are a client, and we've finished reading the server's
* response. Parse it and act appropriately.
*
* If we're still happy with using this directory server in the future, return
* 0. Otherwise return -1; and the caller should consider trying the request
* again.
*
* The caller will take care of marking the connection for close.
*/
static int
connection_dir_client_reached_eof(dir_connection_t *conn)
{
char *body;
char *headers;
char *reason = NULL;
size_t body_len=0, orig_len=0;
int status_code;
time_t date_header=0;
long delta;
compress_method_t compression;
int plausible;
int skewed=0;
int allow_partial = (conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
conn->_base.purpose == DIR_PURPOSE_FETCH_EXTRAINFO);
int was_compressed=0;
time_t now = time(NULL);
switch (fetch_from_buf_http(conn->_base.inbuf,
&headers, MAX_HEADERS_SIZE,
&body, &body_len, MAX_DIR_DL_SIZE,
allow_partial)) {
case -1: /* overflow */
log_warn(LD_PROTOCOL,
"'fetch' response too large (server '%s:%d'). Closing.",
conn->_base.address, conn->_base.port);
return -1;
case 0:
log_info(LD_HTTP,
"'fetch' response not all here, but we're at eof. Closing.");
return -1;
/* case 1, fall through */
}
orig_len = body_len;
if (parse_http_response(headers, &status_code, &date_header,
&compression, &reason) < 0) {
log_warn(LD_HTTP,"Unparseable headers (server '%s:%d'). Closing.",
conn->_base.address, conn->_base.port);
tor_free(body); tor_free(headers);
return -1;
}
if (!reason) reason = tor_strdup("[no reason given]");
log_debug(LD_DIR,
"Received response from directory server '%s:%d': %d %s",
conn->_base.address, conn->_base.port, status_code,
escaped(reason));
/* now check if it's got any hints for us about our IP address. */
if (conn->dirconn_direct) {
char *guess = http_get_header(headers, X_ADDRESS_HEADER);
if (guess) {
router_new_address_suggestion(guess, conn);
tor_free(guess);
}
}
if (date_header > 0) {
/* The date header was written very soon after we sent our request,
* so compute the skew as the difference between sending the request
* and the date header. (We used to check now-date_header, but that's
* inaccurate if we spend a lot of time downloading.)
*/
delta = conn->_base.timestamp_lastwritten - date_header;
if (labs(delta)>ALLOW_DIRECTORY_TIME_SKEW) {
char dbuf[64];
int trusted = router_digest_is_trusted_dir(conn->identity_digest);
format_time_interval(dbuf, sizeof(dbuf), delta);
log_fn(trusted ? LOG_WARN : LOG_INFO,
LD_HTTP,
"Received directory with skewed time (server '%s:%d'): "
"It seems that our clock is %s by %s, or that theirs is %s. "
"Tor requires an accurate clock to work: please check your time, "
"timezone, and date settings.",
conn->_base.address, conn->_base.port,
delta>0 ? "ahead" : "behind", dbuf,
delta>0 ? "behind" : "ahead");
skewed = 1; /* don't check the recommended-versions line */
control_event_general_status(trusted ? LOG_WARN : LOG_NOTICE,
"CLOCK_SKEW SKEW=%ld SOURCE=DIRSERV:%s:%d",
delta, conn->_base.address, conn->_base.port);
} else {
log_debug(LD_HTTP, "Time on received directory is within tolerance; "
"we are %ld seconds skewed. (That's okay.)", delta);
}
}
(void) skewed; /* skewed isn't used yet. */
if (status_code == 503 && body_len < 16) {
routerstatus_t *rs;
trusted_dir_server_t *ds;
log_info(LD_DIR,"Received http status code %d (%s) from server "
"'%s:%d'. I'll try again soon.",
status_code, escaped(reason), conn->_base.address,
conn->_base.port);
if ((rs = router_get_consensus_status_by_id(conn->identity_digest)))
rs->last_dir_503_at = now;
if ((ds = router_get_trusteddirserver_by_digest(conn->identity_digest)))
ds->fake_status.last_dir_503_at = now;
tor_free(body); tor_free(headers); tor_free(reason);
return -1;
} else if (status_code == 503) {
/* XXXX022 Remove this once every server with bug 539 is obsolete. */
log_info(LD_DIR, "Server at '%s:%d' sent us a 503 response, but included "
"a body anyway. We'll pretend it gave us a 200.",
conn->_base.address, conn->_base.port);
status_code = 200;
}
plausible = body_is_plausible(body, body_len, conn->_base.purpose);
if (compression != NO_METHOD || !plausible) {
char *new_body = NULL;
size_t new_len = 0;
compress_method_t guessed = detect_compression_method(body, body_len);
if (compression == UNKNOWN_METHOD || guessed != compression) {
/* Tell the user if we don't believe what we're told about compression.*/
const char *description1, *description2;
if (compression == ZLIB_METHOD)
description1 = "as deflated";
else if (compression == GZIP_METHOD)
description1 = "as gzipped";
else if (compression == NO_METHOD)
description1 = "as uncompressed";
else
description1 = "with an unknown Content-Encoding";
if (guessed == ZLIB_METHOD)
description2 = "deflated";
else if (guessed == GZIP_METHOD)
description2 = "gzipped";
else if (!plausible)
description2 = "confusing binary junk";
else
description2 = "uncompressed";
log_info(LD_HTTP, "HTTP body from server '%s:%d' was labeled %s, "
"but it seems to be %s.%s",
conn->_base.address, conn->_base.port, description1,
description2,
(compression>0 && guessed>0)?" Trying both.":"");
}
/* Try declared compression first if we can. */
if (compression == GZIP_METHOD || compression == ZLIB_METHOD)
tor_gzip_uncompress(&new_body, &new_len, body, body_len, compression,
!allow_partial, LOG_PROTOCOL_WARN);
/* Okay, if that didn't work, and we think that it was compressed
* differently, try that. */
if (!new_body &&
(guessed == GZIP_METHOD || guessed == ZLIB_METHOD) &&
compression != guessed)
tor_gzip_uncompress(&new_body, &new_len, body, body_len, guessed,
!allow_partial, LOG_PROTOCOL_WARN);
/* If we're pretty sure that we have a compressed directory, and
* we didn't manage to uncompress it, then warn and bail. */
if (!plausible && !new_body) {
log_fn(LOG_PROTOCOL_WARN, LD_HTTP,
"Unable to decompress HTTP body (server '%s:%d').",
conn->_base.address, conn->_base.port);
tor_free(body); tor_free(headers); tor_free(reason);
return -1;
}
if (new_body) {
tor_free(body);
body = new_body;
body_len = new_len;
was_compressed = 1;
}
}
if (conn->_base.purpose == DIR_PURPOSE_FETCH_V2_NETWORKSTATUS) {
smartlist_t *which = NULL;
v2_networkstatus_source_t source;
char *cp;
log_info(LD_DIR,"Received networkstatus objects (size %d) from server "
"'%s:%d'",(int) body_len, conn->_base.address, conn->_base.port);
if (status_code != 200) {
log_warn(LD_DIR,
"Received http status code %d (%s) from server "
"'%s:%d' while fetching "/tor/status/%s". I'll try again soon.",
status_code, escaped(reason), conn->_base.address,
conn->_base.port, conn->requested_resource);
tor_free(body); tor_free(headers); tor_free(reason);
connection_dir_download_networkstatus_failed(conn, status_code);
return -1;
}
if (conn->requested_resource &&
!strcmpstart(conn->requested_resource,"fp/")) {
source = NS_FROM_DIR_BY_FP;
which = smartlist_create();
dir_split_resource_into_fingerprints(conn->requested_resource+3,
which, NULL, 0, 0);
} else if (conn->requested_resource &&
!strcmpstart(conn->requested_resource, "all")) {
source = NS_FROM_DIR_ALL;
which = smartlist_create();
SMARTLIST_FOREACH(router_get_trusted_dir_servers(),
trusted_dir_server_t *, ds,
{
char *hex = tor_malloc(HEX_DIGEST_LEN+1);
base16_encode(hex, HEX_DIGEST_LEN+1, ds->digest, DIGEST_LEN);
smartlist_add(which, hex);
});
} else {
/* XXXX Can we even end up here? -- weasel*/
source = NS_FROM_DIR_BY_FP;
log_warn(LD_BUG, "We received a networkstatus but we didn't ask "
"for it by fp, nor did we ask for all.");
}
cp = body;
while (*cp) {
char *next = strstr(cp, "nnetwork-status-version");
if (next)
next[1] = '';
/* learn from it, and then remove it from 'which' */
if (router_set_networkstatus_v2(cp, now, source, which)<0)
break;
if (next) {
next[1] = 'n';
cp = next+1;
} else
break;
}
/* launches router downloads as needed */
routers_update_all_from_networkstatus(now, 2);
directory_info_has_arrived(now, 0);
if (which) {
if (smartlist_len(which)) {
dir_networkstatus_download_failed(which, status_code);
}
SMARTLIST_FOREACH(which, char *, s, tor_free(s));
smartlist_free(which);
}
}
if (conn->_base.purpose == DIR_PURPOSE_FETCH_CONSENSUS) {
int r;
if (status_code != 200) {
int severity = (status_code == 304) ? LOG_INFO : LOG_WARN;
log(severity, LD_DIR,
"Received http status code %d (%s) from server "
"'%s:%d' while fetching consensus directory.",
status_code, escaped(reason), conn->_base.address,
conn->_base.port);
tor_free(body); tor_free(headers); tor_free(reason);
networkstatus_consensus_download_failed(status_code);
return -1;
}
log_info(LD_DIR,"Received consensus directory (size %d) from server "
"'%s:%d'",(int) body_len, conn->_base.address, conn->_base.port);
if ((r=networkstatus_set_current_consensus(body, 0))<0) {
log_fn(r<-1?LOG_WARN:LOG_INFO, LD_DIR,
"Unable to load consensus directory downloaded from "
"server '%s:%d'. I'll try again soon.",
conn->_base.address, conn->_base.port);
tor_free(body); tor_free(headers); tor_free(reason);
networkstatus_consensus_download_failed(0);
return -1;
}
/* launches router downloads as needed */
routers_update_all_from_networkstatus(now, 3);
directory_info_has_arrived(now, 0);
log_info(LD_DIR, "Successfully loaded consensus.");
}
if (conn->_base.purpose == DIR_PURPOSE_FETCH_CERTIFICATE) {
if (status_code != 200) {
log_warn(LD_DIR,
"Received http status code %d (%s) from server "
"'%s:%d' while fetching "/tor/keys/%s".",
status_code, escaped(reason), conn->_base.address,
conn->_base.port, conn->requested_resource);
connection_dir_download_cert_failed(conn, status_code);
tor_free(body); tor_free(headers); tor_free(reason);
return -1;
}
log_info(LD_DIR,"Received authority certificates (size %d) from server "
"'%s:%d'",(int) body_len, conn->_base.address, conn->_base.port);
if (trusted_dirs_load_certs_from_string(body, 0, 1)<0) {
log_warn(LD_DIR, "Unable to parse fetched certificates");
connection_dir_download_cert_failed(conn, status_code);
} else {
directory_info_has_arrived(now, 0);
log_info(LD_DIR, "Successfully loaded certificates from fetch.");
}
}
if (conn->_base.purpose == DIR_PURPOSE_FETCH_STATUS_VOTE) {
const char *msg;
int st;
log_info(LD_DIR,"Got votes (size %d) from server %s:%d",
(int) body_len, conn->_base.address, conn->_base.port);
if (status_code != 200) {
log_warn(LD_DIR,
"Received http status code %d (%s) from server "
"'%s:%d' while fetching "/tor/status-vote/next/%s.z".",
status_code, escaped(reason), conn->_base.address,
conn->_base.port, conn->requested_resource);
tor_free(body); tor_free(headers); tor_free(reason);
return -1;
}
dirvote_add_vote(body, &msg, &st);
if (st > 299) {
log_warn(LD_DIR, "Error adding retrieved vote: %s", msg);
} else {
log_info(LD_DIR, "Added vote(s) successfully [msg: %s]", msg);
}
}
if (conn->_base.purpose == DIR_PURPOSE_FETCH_DETACHED_SIGNATURES) {
const char *msg = NULL;
log_info(LD_DIR,"Got detached signatures (size %d) from server %s:%d",
(int) body_len, conn->_base.address, conn->_base.port);
if (status_code != 200) {
log_warn(LD_DIR,
"Received http status code %d (%s) from server "
"'%s:%d' while fetching "/tor/status-vote/consensus-signatures.z".",
status_code, escaped(reason), conn->_base.address,
conn->_base.port);
tor_free(body); tor_free(headers); tor_free(reason);
return -1;
}
if (dirvote_add_signatures(body, conn->_base.address, &msg)<0) {
log_warn(LD_DIR, "Problem adding detached signatures from %s:%d: %s",
conn->_base.address, conn->_base.port, msg?msg:"???");
}
}
if (conn->_base.purpose == DIR_PURPOSE_FETCH_SERVERDESC ||
conn->_base.purpose == DIR_PURPOSE_FETCH_EXTRAINFO) {
int was_ei = conn->_base.purpose == DIR_PURPOSE_FETCH_EXTRAINFO;
smartlist_t *which = NULL;
int n_asked_for = 0;
int descriptor_digests = conn->requested_resource &&
!strcmpstart(conn->requested_resource,"d/");
log_info(LD_DIR,"Received %s (size %d) from server '%s:%d'",
was_ei ? "extra server info" : "server info",
(int)body_len, conn->_base.address, conn->_base.port);
if (conn->requested_resource &&
(!strcmpstart(conn->requested_resource,"d/") ||
!strcmpstart(conn->requested_resource,"fp/"))) {
which = smartlist_create();
dir_split_resource_into_fingerprints(conn->requested_resource +
(descriptor_digests ? 2 : 3),
which, NULL, 0, 0);
n_asked_for = smartlist_len(which);
}
if (status_code != 200) {
int dir_okay = status_code == 404 ||
(status_code == 400 && !strcmp(reason, "Servers unavailable."));
/* 404 means that it didn't have them; no big deal.
* Older (pre-0.1.1.8) servers said 400 Servers unavailable instead. */
log_fn(dir_okay ? LOG_INFO : LOG_WARN, LD_DIR,
"Received http status code %d (%s) from server '%s:%d' "
"while fetching "/tor/server/%s". I'll try again soon.",
status_code, escaped(reason), conn->_base.address,
conn->_base.port, conn->requested_resource);
if (!which) {
connection_dir_download_routerdesc_failed(conn);
} else {
dir_routerdesc_download_failed(which, status_code,
conn->router_purpose,
was_ei, descriptor_digests);
SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
smartlist_free(which);
}
tor_free(body); tor_free(headers); tor_free(reason);
return dir_okay ? 0 : -1;
}
/* Learn the routers, assuming we requested by fingerprint or "all"
* or "authority".
*
* We use "authority" to fetch our own descriptor for
* testing, and to fetch bridge descriptors for bootstrapping. Ignore
* the output of "authority" requests unless we are using bridges,
* since otherwise they'll be the response from reachability tests,
* and we don't really want to add that to our routerlist. */
if (which || (conn->requested_resource &&
(!strcmpstart(conn->requested_resource, "all") ||
(!strcmpstart(conn->requested_resource, "authority") &&
get_options()->UseBridges)))) {
/* as we learn from them, we remove them from 'which' */
if (was_ei) {
router_load_extrainfo_from_string(body, NULL, SAVED_NOWHERE, which,
descriptor_digests);
} else {
//router_load_routers_from_string(body, NULL, SAVED_NOWHERE, which,
// descriptor_digests, conn->router_purpose);
if (load_downloaded_routers(body, which, descriptor_digests,
conn->router_purpose,
conn->_base.address))
directory_info_has_arrived(now, 0);
}
}
if (which) { /* mark remaining ones as failed */
log_info(LD_DIR, "Received %d/%d %s requested from %s:%d",
n_asked_for-smartlist_len(which), n_asked_for,
was_ei ? "extra-info documents" : "router descriptors",
conn->_base.address, (int)conn->_base.port);
if (smartlist_len(which)) {
dir_routerdesc_download_failed(which, status_code,
conn->router_purpose,
was_ei, descriptor_digests);
}
SMARTLIST_FOREACH(which, char *, cp, tor_free(cp));
smartlist_free(which);
}
if (directory_conn_is_self_reachability_test(conn))
router_dirport_found_reachable();