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e6a581f126
tor/src/or/rendcommon.c
David Goulet e6a581f126 Add a create function for rend_data_t object 
Ground works for fixing #15816. This adds the rend_data_create() function in
order to have a single place where we initialize that data structure.

Furthermore, an array of descriptor IDs is added (one per replica) so we can
keep a copy of the current id in the object. It will be used to purge the
last hid serv request cache using those descriptor IDs. When they change,
they will be replaced and the old ones will be purged from the cache.

Signed-off-by: David Goulet <dgoulet@ev0ke.net>
2015-04-30 12:35:20 -04:00

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/* Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
* Copyright (c) 2007-2015, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file rendcommon.c
* \brief Rendezvous implementation: shared code between
* introducers, services, clients, and rendezvous points.
**/
#include "or.h"
#include "circuitbuild.h"
#include "config.h"
#include "rendclient.h"
#include "rendcommon.h"
#include "rendmid.h"
#include "rendservice.h"
#include "rephist.h"
#include "routerlist.h"
#include "routerparse.h"
/** Return 0 if one and two are the same service ids, else -1 or 1 */
int
rend_cmp_service_ids(const char *one, const char *two)
{
return strcasecmp(one,two);
}
/** Free the storage held by the service descriptor <b>desc</b>.
*/
void
rend_service_descriptor_free(rend_service_descriptor_t *desc)
{
if (!desc)
return;
if (desc->pk)
crypto_pk_free(desc->pk);
if (desc->intro_nodes) {
SMARTLIST_FOREACH(desc->intro_nodes, rend_intro_point_t *, intro,
rend_intro_point_free(intro););
smartlist_free(desc->intro_nodes);
}
if (desc->successful_uploads) {
SMARTLIST_FOREACH(desc->successful_uploads, char *, c, tor_free(c););
smartlist_free(desc->successful_uploads);
}
tor_free(desc);
}
/** Length of the descriptor cookie that is used for versioned hidden
* service descriptors. */
#define REND_DESC_COOKIE_LEN 16
/** Length of the replica number that is used to determine the secret ID
* part of versioned hidden service descriptors. */
#define REND_REPLICA_LEN 1
/** Compute the descriptor ID for <b>service_id</b> of length
* <b>REND_SERVICE_ID_LEN</b> and <b>secret_id_part</b> of length
* <b>DIGEST_LEN</b>, and write it to <b>descriptor_id_out</b> of length
* <b>DIGEST_LEN</b>. */
void
rend_get_descriptor_id_bytes(char *descriptor_id_out,
const char *service_id,
const char *secret_id_part)
{
crypto_digest_t *digest = crypto_digest_new();
crypto_digest_add_bytes(digest, service_id, REND_SERVICE_ID_LEN);
crypto_digest_add_bytes(digest, secret_id_part, DIGEST_LEN);
crypto_digest_get_digest(digest, descriptor_id_out, DIGEST_LEN);
crypto_digest_free(digest);
}
/** Compute the secret ID part for time_period,
* a <b>descriptor_cookie</b> of length
* <b>REND_DESC_COOKIE_LEN</b> which may also be <b>NULL</b> if no
* descriptor_cookie shall be used, and <b>replica</b>, and write it to
* <b>secret_id_part</b> of length DIGEST_LEN. */
static void
get_secret_id_part_bytes(char *secret_id_part, uint32_t time_period,
const char *descriptor_cookie, uint8_t replica)
{
crypto_digest_t *digest = crypto_digest_new();
time_period = htonl(time_period);
crypto_digest_add_bytes(digest, (char*)&time_period, sizeof(uint32_t));
if (descriptor_cookie) {
crypto_digest_add_bytes(digest, descriptor_cookie,
REND_DESC_COOKIE_LEN);
}
crypto_digest_add_bytes(digest, (const char *)&replica, REND_REPLICA_LEN);
crypto_digest_get_digest(digest, secret_id_part, DIGEST_LEN);
crypto_digest_free(digest);
}
/** Return the time period for time <b>now</b> plus a potentially
* intended <b>deviation</b> of one or more periods, based on the first byte
* of <b>service_id</b>. */
static uint32_t
get_time_period(time_t now, uint8_t deviation, const char *service_id)
{
/* The time period is the number of REND_TIME_PERIOD_V2_DESC_VALIDITY
* intervals that have passed since the epoch, offset slightly so that
* each service's time periods start and end at a fraction of that
* period based on their first byte. */
return (uint32_t)
(now + ((uint8_t) *service_id) * REND_TIME_PERIOD_V2_DESC_VALIDITY / 256)
/ REND_TIME_PERIOD_V2_DESC_VALIDITY + deviation;
}
/** Compute the time in seconds that a descriptor that is generated
* <b>now</b> for <b>service_id</b> will be valid. */
static uint32_t
get_seconds_valid(time_t now, const char *service_id)
{
uint32_t result = REND_TIME_PERIOD_V2_DESC_VALIDITY -
((uint32_t)
(now + ((uint8_t) *service_id) * REND_TIME_PERIOD_V2_DESC_VALIDITY / 256)
% REND_TIME_PERIOD_V2_DESC_VALIDITY);
return result;
}
/** Compute the binary <b>desc_id_out</b> (DIGEST_LEN bytes long) for a given
* base32-encoded <b>service_id</b> and optional unencoded
* <b>descriptor_cookie</b> of length REND_DESC_COOKIE_LEN,
* at time <b>now</b> for replica number
* <b>replica</b>. <b>desc_id</b> needs to have <b>DIGEST_LEN</b> bytes
* free. Return 0 for success, -1 otherwise. */
int
rend_compute_v2_desc_id(char *desc_id_out, const char *service_id,
const char *descriptor_cookie, time_t now,
uint8_t replica)
{
char service_id_binary[REND_SERVICE_ID_LEN];
char secret_id_part[DIGEST_LEN];
uint32_t time_period;
if (!service_id ||
strlen(service_id) != REND_SERVICE_ID_LEN_BASE32) {
log_warn(LD_REND, "Could not compute v2 descriptor ID: "
"Illegal service ID: %s",
safe_str(service_id));
return -1;
}
if (replica >= REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS) {
log_warn(LD_REND, "Could not compute v2 descriptor ID: "
"Replica number out of range: %d", replica);
return -1;
}
/* Convert service ID to binary. */
if (base32_decode(service_id_binary, REND_SERVICE_ID_LEN,
service_id, REND_SERVICE_ID_LEN_BASE32) < 0) {
log_warn(LD_REND, "Could not compute v2 descriptor ID: "
"Illegal characters in service ID: %s",
safe_str_client(service_id));
return -1;
}
/* Calculate current time-period. */
time_period = get_time_period(now, 0, service_id_binary);
/* Calculate secret-id-part = h(time-period | replica). */
get_secret_id_part_bytes(secret_id_part, time_period, descriptor_cookie,
replica);
/* Calculate descriptor ID. */
rend_get_descriptor_id_bytes(desc_id_out, service_id_binary, secret_id_part);
return 0;
}
/** Encode the introduction points in <b>desc</b> and write the result to a
* newly allocated string pointed to by <b>encoded</b>. Return 0 for
* success, -1 otherwise. */
static int
rend_encode_v2_intro_points(char **encoded, rend_service_descriptor_t *desc)
{
size_t unenc_len;
char *unenc = NULL;
size_t unenc_written = 0;
int i;
int r = -1;
/* Assemble unencrypted list of introduction points. */
unenc_len = smartlist_len(desc->intro_nodes) * 1000; /* too long, but ok. */
unenc = tor_malloc_zero(unenc_len);
for (i = 0; i < smartlist_len(desc->intro_nodes); i++) {
char id_base32[REND_INTRO_POINT_ID_LEN_BASE32 + 1];
char *onion_key = NULL;
size_t onion_key_len;
crypto_pk_t *intro_key;
char *service_key = NULL;
char *address = NULL;
size_t service_key_len;
int res;
rend_intro_point_t *intro = smartlist_get(desc->intro_nodes, i);
/* Obtain extend info with introduction point details. */
extend_info_t *info = intro->extend_info;
/* Encode introduction point ID. */
base32_encode(id_base32, sizeof(id_base32),
info->identity_digest, DIGEST_LEN);
/* Encode onion key. */
if (crypto_pk_write_public_key_to_string(info->onion_key, &onion_key,
&onion_key_len) < 0) {
log_warn(LD_REND, "Could not write onion key.");
goto done;
}
/* Encode intro key. */
intro_key = intro->intro_key;
if (!intro_key ||
crypto_pk_write_public_key_to_string(intro_key, &service_key,
&service_key_len) < 0) {
log_warn(LD_REND, "Could not write intro key.");
tor_free(onion_key);
goto done;
}
/* Assemble everything for this introduction point. */
address = tor_dup_addr(&info->addr);
res = tor_snprintf(unenc + unenc_written, unenc_len - unenc_written,
"introduction-point %s\n"
"ip-address %s\n"
"onion-port %d\n"
"onion-key\n%s"
"service-key\n%s",
id_base32,
address,
info->port,
onion_key,
service_key);
tor_free(address);
tor_free(onion_key);
tor_free(service_key);
if (res < 0) {
log_warn(LD_REND, "Not enough space for writing introduction point "
"string.");
goto done;
}
/* Update total number of written bytes for unencrypted intro points. */
unenc_written += res;
}
/* Finalize unencrypted introduction points. */
if (unenc_len < unenc_written + 2) {
log_warn(LD_REND, "Not enough space for finalizing introduction point "
"string.");
goto done;
}
unenc[unenc_written++] = '\n';
unenc[unenc_written++] = 0;
*encoded = unenc;
r = 0;
done:
if (r<0)
tor_free(unenc);
return r;
}
/** Encrypt the encoded introduction points in <b>encoded</b> using
* authorization type 'basic' with <b>client_cookies</b> and write the
* result to a newly allocated string pointed to by <b>encrypted_out</b> of
* length <b>encrypted_len_out</b>. Return 0 for success, -1 otherwise. */
static int
rend_encrypt_v2_intro_points_basic(char **encrypted_out,
size_t *encrypted_len_out,
const char *encoded,
smartlist_t *client_cookies)
{
int r = -1, i, pos, enclen, client_blocks;
size_t len, client_entries_len;
char *enc = NULL, iv[CIPHER_IV_LEN], *client_part = NULL,
session_key[CIPHER_KEY_LEN];
smartlist_t *encrypted_session_keys = NULL;
crypto_digest_t *digest;
crypto_cipher_t *cipher;
tor_assert(encoded);
tor_assert(client_cookies && smartlist_len(client_cookies) > 0);
/* Generate session key. */
if (crypto_rand(session_key, CIPHER_KEY_LEN) < 0) {
log_warn(LD_REND, "Unable to generate random session key to encrypt "
"introduction point string.");
goto done;
}
/* Determine length of encrypted introduction points including session
* keys. */
client_blocks = 1 + ((smartlist_len(client_cookies) - 1) /
REND_BASIC_AUTH_CLIENT_MULTIPLE);
client_entries_len = client_blocks * REND_BASIC_AUTH_CLIENT_MULTIPLE *
REND_BASIC_AUTH_CLIENT_ENTRY_LEN;
len = 2 + client_entries_len + CIPHER_IV_LEN + strlen(encoded);
if (client_blocks >= 256) {
log_warn(LD_REND, "Too many clients in introduction point string.");
goto done;
}
enc = tor_malloc_zero(len);
enc[0] = 0x01; /* type of authorization. */
enc[1] = (uint8_t)client_blocks;
/* Encrypt with random session key. */
enclen = crypto_cipher_encrypt_with_iv(session_key,
enc + 2 + client_entries_len,
CIPHER_IV_LEN + strlen(encoded), encoded, strlen(encoded));
if (enclen < 0) {
log_warn(LD_REND, "Could not encrypt introduction point string.");
goto done;
}
memcpy(iv, enc + 2 + client_entries_len, CIPHER_IV_LEN);
/* Encrypt session key for cookies, determine client IDs, and put both
* in a smartlist. */
encrypted_session_keys = smartlist_new();
SMARTLIST_FOREACH_BEGIN(client_cookies, const char *, cookie) {
client_part = tor_malloc_zero(REND_BASIC_AUTH_CLIENT_ENTRY_LEN);
/* Encrypt session key. */
cipher = crypto_cipher_new(cookie);
if (crypto_cipher_encrypt(cipher, client_part +
REND_BASIC_AUTH_CLIENT_ID_LEN,
session_key, CIPHER_KEY_LEN) < 0) {
log_warn(LD_REND, "Could not encrypt session key for client.");
crypto_cipher_free(cipher);
tor_free(client_part);
goto done;
}
crypto_cipher_free(cipher);
/* Determine client ID. */
digest = crypto_digest_new();
crypto_digest_add_bytes(digest, cookie, REND_DESC_COOKIE_LEN);
crypto_digest_add_bytes(digest, iv, CIPHER_IV_LEN);
crypto_digest_get_digest(digest, client_part,
REND_BASIC_AUTH_CLIENT_ID_LEN);
crypto_digest_free(digest);
/* Put both together. */
smartlist_add(encrypted_session_keys, client_part);
} SMARTLIST_FOREACH_END(cookie);
/* Add some fake client IDs and encrypted session keys. */
for (i = (smartlist_len(client_cookies) - 1) %
REND_BASIC_AUTH_CLIENT_MULTIPLE;
i < REND_BASIC_AUTH_CLIENT_MULTIPLE - 1; i++) {
client_part = tor_malloc_zero(REND_BASIC_AUTH_CLIENT_ENTRY_LEN);
if (crypto_rand(client_part, REND_BASIC_AUTH_CLIENT_ENTRY_LEN) < 0) {
log_warn(LD_REND, "Unable to generate fake client entry.");
tor_free(client_part);
goto done;
}
smartlist_add(encrypted_session_keys, client_part);
}
/* Sort smartlist and put elements in result in order. */
smartlist_sort_digests(encrypted_session_keys);
pos = 2;
SMARTLIST_FOREACH(encrypted_session_keys, const char *, entry, {
memcpy(enc + pos, entry, REND_BASIC_AUTH_CLIENT_ENTRY_LEN);
pos += REND_BASIC_AUTH_CLIENT_ENTRY_LEN;
});
*encrypted_out = enc;
*encrypted_len_out = len;
enc = NULL; /* prevent free. */
r = 0;
done:
tor_free(enc);
if (encrypted_session_keys) {
SMARTLIST_FOREACH(encrypted_session_keys, char *, d, tor_free(d););
smartlist_free(encrypted_session_keys);
}
return r;
}
/** Encrypt the encoded introduction points in <b>encoded</b> using
* authorization type 'stealth' with <b>descriptor_cookie</b> of length
* REND_DESC_COOKIE_LEN and write the result to a newly allocated string
* pointed to by <b>encrypted_out</b> of length <b>encrypted_len_out</b>.
* Return 0 for success, -1 otherwise. */
static int
rend_encrypt_v2_intro_points_stealth(char **encrypted_out,
size_t *encrypted_len_out,
const char *encoded,
const char *descriptor_cookie)
{
int r = -1, enclen;
char *enc;
tor_assert(encoded);
tor_assert(descriptor_cookie);
enc = tor_malloc_zero(1 + CIPHER_IV_LEN + strlen(encoded));
enc[0] = 0x02; /* Auth type */
enclen = crypto_cipher_encrypt_with_iv(descriptor_cookie,
enc + 1,
CIPHER_IV_LEN+strlen(encoded),
encoded, strlen(encoded));
if (enclen < 0) {
log_warn(LD_REND, "Could not encrypt introduction point string.");
goto done;
}
*encrypted_out = enc;
*encrypted_len_out = enclen;
enc = NULL; /* prevent free */
r = 0;
done:
tor_free(enc);
return r;
}
/** Attempt to parse the given <b>desc_str</b> and return true if this
* succeeds, false otherwise. */
static int
rend_desc_v2_is_parsable(rend_encoded_v2_service_descriptor_t *desc)
{
rend_service_descriptor_t *test_parsed = NULL;
char test_desc_id[DIGEST_LEN];
char *test_intro_content = NULL;
size_t test_intro_size;
size_t test_encoded_size;
const char *test_next;
int res = rend_parse_v2_service_descriptor(&test_parsed, test_desc_id,
&test_intro_content,
&test_intro_size,
&test_encoded_size,
&test_next, desc->desc_str, 1);
rend_service_descriptor_free(test_parsed);
tor_free(test_intro_content);
return (res >= 0);
}
/** Free the storage held by an encoded v2 service descriptor. */
void
rend_encoded_v2_service_descriptor_free(
rend_encoded_v2_service_descriptor_t *desc)
{
if (!desc)
return;
tor_free(desc->desc_str);
tor_free(desc);
}
/** Free the storage held by an introduction point info. */
void
rend_intro_point_free(rend_intro_point_t *intro)
{
if (!intro)
return;
extend_info_free(intro->extend_info);
crypto_pk_free(intro->intro_key);
if (intro->accepted_intro_rsa_parts != NULL) {
replaycache_free(intro->accepted_intro_rsa_parts);
}
tor_free(intro);
}
/** Encode a set of rend_encoded_v2_service_descriptor_t's for <b>desc</b>
* at time <b>now</b> using <b>service_key</b>, depending on
* <b>auth_type</b> a <b>descriptor_cookie</b> and a list of
* <b>client_cookies</b> (which are both <b>NULL</b> if no client
* authorization is performed), and <b>period</b> (e.g. 0 for the current
* period, 1 for the next period, etc.) and add them to the existing list
* <b>descs_out</b>; return the number of seconds that the descriptors will
* be found by clients, or -1 if the encoding was not successful. */
int
rend_encode_v2_descriptors(smartlist_t *descs_out,
rend_service_descriptor_t *desc, time_t now,
uint8_t period, rend_auth_type_t auth_type,
crypto_pk_t *client_key,
smartlist_t *client_cookies)
{
char service_id[DIGEST_LEN];
uint32_t time_period;
char *ipos_base64 = NULL, *ipos = NULL, *ipos_encrypted = NULL,
*descriptor_cookie = NULL;
size_t ipos_len = 0, ipos_encrypted_len = 0;
int k;
uint32_t seconds_valid;
crypto_pk_t *service_key;
if (!desc) {
log_warn(LD_BUG, "Could not encode v2 descriptor: No desc given.");
return -1;
}
service_key = (auth_type == REND_STEALTH_AUTH) ? client_key : desc->pk;
tor_assert(service_key);
if (auth_type == REND_STEALTH_AUTH) {
descriptor_cookie = smartlist_get(client_cookies, 0);
tor_assert(descriptor_cookie);
}
/* Obtain service_id from public key. */
crypto_pk_get_digest(service_key, service_id);
/* Calculate current time-period. */
time_period = get_time_period(now, period, service_id);
/* Determine how many seconds the descriptor will be valid. */
seconds_valid = period * REND_TIME_PERIOD_V2_DESC_VALIDITY +
get_seconds_valid(now, service_id);
/* Assemble, possibly encrypt, and encode introduction points. */
if (smartlist_len(desc->intro_nodes) > 0) {
if (rend_encode_v2_intro_points(&ipos, desc) < 0) {
log_warn(LD_REND, "Encoding of introduction points did not succeed.");
return -1;
}
switch (auth_type) {
case REND_NO_AUTH:
ipos_len = strlen(ipos);
break;
case REND_BASIC_AUTH:
if (rend_encrypt_v2_intro_points_basic(&ipos_encrypted,
&ipos_encrypted_len, ipos,
client_cookies) < 0) {
log_warn(LD_REND, "Encrypting of introduction points did not "
"succeed.");
tor_free(ipos);
return -1;
}
tor_free(ipos);
ipos = ipos_encrypted;
ipos_len = ipos_encrypted_len;
break;
case REND_STEALTH_AUTH:
if (rend_encrypt_v2_intro_points_stealth(&ipos_encrypted,
&ipos_encrypted_len, ipos,
descriptor_cookie) < 0) {
log_warn(LD_REND, "Encrypting of introduction points did not "
"succeed.");
tor_free(ipos);
return -1;
}
tor_free(ipos);
ipos = ipos_encrypted;
ipos_len = ipos_encrypted_len;
break;
default:
log_warn(LD_REND|LD_BUG, "Unrecognized authorization type %d",
(int)auth_type);
tor_free(ipos);
return -1;
}
/* Base64-encode introduction points. */
ipos_base64 = tor_calloc(ipos_len, 2);
if (base64_encode(ipos_base64, ipos_len * 2, ipos, ipos_len,
BASE64_ENCODE_MULTILINE)<0) {
log_warn(LD_REND, "Could not encode introduction point string to "
"base64. length=%d", (int)ipos_len);
tor_free(ipos_base64);
tor_free(ipos);
return -1;
}
tor_free(ipos);
}
/* Encode REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS descriptors. */
for (k = 0; k < REND_NUMBER_OF_NON_CONSECUTIVE_REPLICAS; k++) {
char secret_id_part[DIGEST_LEN];
char secret_id_part_base32[REND_SECRET_ID_PART_LEN_BASE32 + 1];
char desc_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
char *permanent_key = NULL;
size_t permanent_key_len;
char published[ISO_TIME_LEN+1];
int i;
char protocol_versions_string[16]; /* max len: "0,1,2,3,4,5,6,7\0" */
size_t protocol_versions_written;
size_t desc_len;
char *desc_str = NULL;
int result = 0;
size_t written = 0;
char desc_digest[DIGEST_LEN];
rend_encoded_v2_service_descriptor_t *enc =
tor_malloc_zero(sizeof(rend_encoded_v2_service_descriptor_t));
/* Calculate secret-id-part = h(time-period | cookie | replica). */
get_secret_id_part_bytes(secret_id_part, time_period, descriptor_cookie,
k);
base32_encode(secret_id_part_base32, sizeof(secret_id_part_base32),
secret_id_part, DIGEST_LEN);
/* Calculate descriptor ID. */
rend_get_descriptor_id_bytes(enc->desc_id, service_id, secret_id_part);
base32_encode(desc_id_base32, sizeof(desc_id_base32),
enc->desc_id, DIGEST_LEN);
/* PEM-encode the public key */
if (crypto_pk_write_public_key_to_string(service_key, &permanent_key,
&permanent_key_len) < 0) {
log_warn(LD_BUG, "Could not write public key to string.");
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
/* Encode timestamp. */
format_iso_time(published, desc->timestamp);
/* Write protocol-versions bitmask to comma-separated value string. */
protocol_versions_written = 0;
for (i = 0; i < 8; i++) {
if (desc->protocols & 1 << i) {
tor_snprintf(protocol_versions_string + protocol_versions_written,
16 - protocol_versions_written, "%d,", i);
protocol_versions_written += 2;
}
}
if (protocol_versions_written)
protocol_versions_string[protocol_versions_written - 1] = '\0';
else
protocol_versions_string[0]= '\0';
/* Assemble complete descriptor. */
desc_len = 2000 + smartlist_len(desc->intro_nodes) * 1000; /* far too long,
but okay.*/
enc->desc_str = desc_str = tor_malloc_zero(desc_len);
result = tor_snprintf(desc_str, desc_len,
"rendezvous-service-descriptor %s\n"
"version 2\n"
"permanent-key\n%s"
"secret-id-part %s\n"
"publication-time %s\n"
"protocol-versions %s\n",
desc_id_base32,
permanent_key,
secret_id_part_base32,
published,
protocol_versions_string);
tor_free(permanent_key);
if (result < 0) {
log_warn(LD_BUG, "Descriptor ran out of room.");
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
written = result;
/* Add introduction points. */
if (ipos_base64) {
result = tor_snprintf(desc_str + written, desc_len - written,
"introduction-points\n"
"-----BEGIN MESSAGE-----\n%s"
"-----END MESSAGE-----\n",
ipos_base64);
if (result < 0) {
log_warn(LD_BUG, "could not write introduction points.");
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
written += result;
}
/* Add signature. */
strlcpy(desc_str + written, "signature\n", desc_len - written);
written += strlen(desc_str + written);
if (crypto_digest(desc_digest, desc_str, written) < 0) {
log_warn(LD_BUG, "could not create digest.");
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
if (router_append_dirobj_signature(desc_str + written,
desc_len - written,
desc_digest, DIGEST_LEN,
service_key) < 0) {
log_warn(LD_BUG, "Couldn't sign desc.");
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
written += strlen(desc_str+written);
if (written+2 > desc_len) {
log_warn(LD_BUG, "Could not finish desc.");
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
desc_str[written++] = 0;
/* Check if we can parse our own descriptor. */
if (!rend_desc_v2_is_parsable(enc)) {
log_warn(LD_BUG, "Could not parse my own descriptor: %s", desc_str);
rend_encoded_v2_service_descriptor_free(enc);
goto err;
}
smartlist_add(descs_out, enc);
}
log_info(LD_REND, "Successfully encoded a v2 descriptor and "
"confirmed that it is parsable.");
goto done;
err:
SMARTLIST_FOREACH(descs_out, rend_encoded_v2_service_descriptor_t *, d,
rend_encoded_v2_service_descriptor_free(d););
smartlist_clear(descs_out);
seconds_valid = -1;
done:
tor_free(ipos_base64);
return seconds_valid;
}
/** Sets <b>out</b> to the first 10 bytes of the digest of <b>pk</b>,
* base32 encoded. NUL-terminates out. (We use this string to
* identify services in directory requests and .onion URLs.)
*/
int
rend_get_service_id(crypto_pk_t *pk, char *out)
{
char buf[DIGEST_LEN];
tor_assert(pk);
if (crypto_pk_get_digest(pk, buf) < 0)
return -1;
base32_encode(out, REND_SERVICE_ID_LEN_BASE32+1, buf, REND_SERVICE_ID_LEN);
return 0;
}
/* ==== Rendezvous service descriptor cache. */
/** How old do we let hidden service descriptors get before discarding
* them as too old? */
#define REND_CACHE_MAX_AGE (2*24*60*60)
/** How wrong do we assume our clock may be when checking whether hidden
* services are too old or too new? */
#define REND_CACHE_MAX_SKEW (24*60*60)
/** Map from service id (as generated by rend_get_service_id) to
* rend_cache_entry_t. */
static strmap_t *rend_cache = NULL;
/** Map from descriptor id to rend_cache_entry_t; only for hidden service
* directories. */
static digestmap_t *rend_cache_v2_dir = NULL;
/** DOCDOC */
static size_t rend_cache_total_allocation = 0;
/** Initializes the service descriptor cache.
*/
void
rend_cache_init(void)
{
rend_cache = strmap_new();
rend_cache_v2_dir = digestmap_new();
}
/** Return the approximate number of bytes needed to hold <b>e</b>. */
static size_t
rend_cache_entry_allocation(const rend_cache_entry_t *e)
{
if (!e)
return 0;
/* This doesn't count intro_nodes or key size */
return sizeof(*e) + e->len + sizeof(*e->parsed);
}
/** DOCDOC */
size_t
rend_cache_get_total_allocation(void)
{
return rend_cache_total_allocation;
}
/** Decrement the total bytes attributed to the rendezvous cache by n. */
static void
rend_cache_decrement_allocation(size_t n)
{
static int have_underflowed = 0;
if (rend_cache_total_allocation >= n) {
rend_cache_total_allocation -= n;
} else {
rend_cache_total_allocation = 0;
if (! have_underflowed) {
have_underflowed = 1;
log_warn(LD_BUG, "Underflow in rend_cache_decrement_allocation");
}
}
}
/** Increase the total bytes attributed to the rendezvous cache by n. */
static void
rend_cache_increment_allocation(size_t n)
{
static int have_overflowed = 0;
if (rend_cache_total_allocation <= SIZE_MAX - n) {
rend_cache_total_allocation += n;
} else {
rend_cache_total_allocation = SIZE_MAX;
if (! have_overflowed) {
have_overflowed = 1;
log_warn(LD_BUG, "Overflow in rend_cache_increment_allocation");
}
}
}
/** Helper: free storage held by a single service descriptor cache entry. */
static void
rend_cache_entry_free(rend_cache_entry_t *e)
{
if (!e)
return;
rend_cache_decrement_allocation(rend_cache_entry_allocation(e));
rend_service_descriptor_free(e->parsed);
tor_free(e->desc);
tor_free(e);
}
/** Helper: deallocate a rend_cache_entry_t. (Used with strmap_free(), which
* requires a function pointer whose argument is void*). */
static void
rend_cache_entry_free_(void *p)
{
rend_cache_entry_free(p);
}
/** Free all storage held by the service descriptor cache. */
void
rend_cache_free_all(void)
{
strmap_free(rend_cache, rend_cache_entry_free_);
digestmap_free(rend_cache_v2_dir, rend_cache_entry_free_);
rend_cache = NULL;
rend_cache_v2_dir = NULL;
rend_cache_total_allocation = 0;
}
/** Removes all old entries from the service descriptor cache.
*/
void
rend_cache_clean(time_t now)
{
strmap_iter_t *iter;
const char *key;
void *val;
rend_cache_entry_t *ent;
time_t cutoff = now - REND_CACHE_MAX_AGE - REND_CACHE_MAX_SKEW;
for (iter = strmap_iter_init(rend_cache); !strmap_iter_done(iter); ) {
strmap_iter_get(iter, &key, &val);
ent = (rend_cache_entry_t*)val;
if (ent->parsed->timestamp < cutoff) {
iter = strmap_iter_next_rmv(rend_cache, iter);
rend_cache_entry_free(ent);
} else {
iter = strmap_iter_next(rend_cache, iter);
}
}
}
/** Remove ALL entries from the rendezvous service descriptor cache.
*/
void
rend_cache_purge(void)
{
if (rend_cache) {
log_info(LD_REND, "Purging HS descriptor cache");
strmap_free(rend_cache, rend_cache_entry_free_);
}
rend_cache = strmap_new();
}
/** Remove all old v2 descriptors and those for which this hidden service
* directory is not responsible for any more.
*
* If at all possible, remove at least <b>force_remove</b> bytes of data.
*/
void
rend_cache_clean_v2_descs_as_dir(time_t now, size_t force_remove)
{
digestmap_iter_t *iter;
time_t cutoff = now - REND_CACHE_MAX_AGE - REND_CACHE_MAX_SKEW;
const int LAST_SERVED_CUTOFF_STEP = 1800;
time_t last_served_cutoff = cutoff;
size_t bytes_removed = 0;
do {
for (iter = digestmap_iter_init(rend_cache_v2_dir);
!digestmap_iter_done(iter); ) {
const char *key;
void *val;
rend_cache_entry_t *ent;
digestmap_iter_get(iter, &key, &val);
ent = val;
if (ent->parsed->timestamp < cutoff ||
ent->last_served < last_served_cutoff ||
!hid_serv_responsible_for_desc_id(key)) {
char key_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
base32_encode(key_base32, sizeof(key_base32), key, DIGEST_LEN);
log_info(LD_REND, "Removing descriptor with ID '%s' from cache",
safe_str_client(key_base32));
bytes_removed += rend_cache_entry_allocation(ent);
iter = digestmap_iter_next_rmv(rend_cache_v2_dir, iter);
rend_cache_entry_free(ent);
} else {
iter = digestmap_iter_next(rend_cache_v2_dir, iter);
}
}
/* In case we didn't remove enough bytes, advance the cutoff a little. */
last_served_cutoff += LAST_SERVED_CUTOFF_STEP;
if (last_served_cutoff > now)
break;
} while (bytes_removed < force_remove);
}
/** Determines whether <b>a</b> is in the interval of <b>b</b> (excluded) and
* <b>c</b> (included) in a circular digest ring; returns 1 if this is the
* case, and 0 otherwise.
*/
int
rend_id_is_in_interval(const char *a, const char *b, const char *c)
{
int a_b, b_c, c_a;
tor_assert(a);
tor_assert(b);
tor_assert(c);
/* There are five cases in which a is outside the interval ]b,c]: */
a_b = tor_memcmp(a,b,DIGEST_LEN);
if (a_b == 0)
return 0; /* 1. a == b (b is excluded) */
b_c = tor_memcmp(b,c,DIGEST_LEN);
if (b_c == 0)
return 0; /* 2. b == c (interval is empty) */
else if (a_b <= 0 && b_c < 0)
return 0; /* 3. a b c */
c_a = tor_memcmp(c,a,DIGEST_LEN);
if (c_a < 0 && a_b <= 0)
return 0; /* 4. c a b */
else if (b_c < 0 && c_a < 0)
return 0; /* 5. b c a */
/* In the other cases (a c b; b a c; c b a), a is inside the interval. */
return 1;
}
/** Return true iff <b>query</b> is a syntactically valid service ID (as
* generated by rend_get_service_id). */
int
rend_valid_service_id(const char *query)
{
if (strlen(query) != REND_SERVICE_ID_LEN_BASE32)
return 0;
if (strspn(query, BASE32_CHARS) != REND_SERVICE_ID_LEN_BASE32)
return 0;
return 1;
}
/** Return true iff <b>query</b> is a syntactically valid descriptor ID.
* (as generated by rend_get_descriptor_id_bytes). */
int
rend_valid_descriptor_id(const char *query)
{
if (strlen(query) != REND_DESC_ID_V2_LEN_BASE32) {
goto invalid;
}
if (strspn(query, BASE32_CHARS) != REND_DESC_ID_V2_LEN_BASE32) {
goto invalid;
}
return 1;
invalid:
return 0;
}
/** Lookup in the client cache the given service ID <b>query</b> for
* <b>version</b>.
*
* Return 0 if found and if <b>e</b> is non NULL, set it with the entry
* found. Else, a negative value is returned and <b>e</b> is untouched.
* -EINVAL means that <b>query</b> is not a valid service id.
* -ENOENT means that no entry in the cache was found. */
int
rend_cache_lookup_entry(const char *query, int version, rend_cache_entry_t **e)
{
int ret = 0;
char key[REND_SERVICE_ID_LEN_BASE32 + 2]; /* <version><query>\0 */
rend_cache_entry_t *entry = NULL;
static const int default_version = 2;
tor_assert(rend_cache);
tor_assert(query);
if (!rend_valid_service_id(query)) {
ret = -EINVAL;
goto end;
}
switch (version) {
case 0:
log_warn(LD_REND, "Cache lookup of a v0 renddesc is deprecated.");
break;
case 2:
/* Default is version 2. */
default:
tor_snprintf(key, sizeof(key), "%d%s", default_version, query);
entry = strmap_get_lc(rend_cache, key);
break;
}
if (!entry) {
ret = -ENOENT;
goto end;
}
tor_assert(entry->parsed && entry->parsed->intro_nodes);
if (e) {
*e = entry;
}
end:
return ret;
}
/** Lookup the v2 service descriptor with base32-encoded <b>desc_id</b> and
* copy the pointer to it to *<b>desc</b>. Return 1 on success, 0 on
* well-formed-but-not-found, and -1 on failure.
*/
int
rend_cache_lookup_v2_desc_as_dir(const char *desc_id, const char **desc)
{
rend_cache_entry_t *e;
char desc_id_digest[DIGEST_LEN];
tor_assert(rend_cache_v2_dir);
if (base32_decode(desc_id_digest, DIGEST_LEN,
desc_id, REND_DESC_ID_V2_LEN_BASE32) < 0) {
log_fn(LOG_PROTOCOL_WARN, LD_REND,
"Rejecting v2 rendezvous descriptor request -- descriptor ID "
"contains illegal characters: %s",
safe_str(desc_id));
return -1;
}
/* Lookup descriptor and return. */
e = digestmap_get(rend_cache_v2_dir, desc_id_digest);
if (e) {
*desc = e->desc;
e->last_served = approx_time();
return 1;
}
return 0;
}
/* Do not allow more than this many introduction points in a hidden service
* descriptor */
#define MAX_INTRO_POINTS 10
/** Parse the v2 service descriptor(s) in <b>desc</b> and store it/them to the
* local rend cache. Don't attempt to decrypt the included list of introduction
* points (as we don't have a descriptor cookie for it).
*
* If we have a newer descriptor with the same ID, ignore this one.
* If we have an older descriptor with the same ID, replace it.
*
* Return an appropriate rend_cache_store_status_t.
*/
rend_cache_store_status_t
rend_cache_store_v2_desc_as_dir(const char *desc)
{
const or_options_t *options = get_options();
rend_service_descriptor_t *parsed;
char desc_id[DIGEST_LEN];
char *intro_content;
size_t intro_size;
size_t encoded_size;
char desc_id_base32[REND_DESC_ID_V2_LEN_BASE32 + 1];
int number_parsed = 0, number_stored = 0;
const char *current_desc = desc;
const char *next_desc;
rend_cache_entry_t *e;
time_t now = time(NULL);
tor_assert(rend_cache_v2_dir);
tor_assert(desc);
if (!hid_serv_acting_as_directory()) {
/* Cannot store descs, because we are (currently) not acting as
* hidden service directory. */
log_info(LD_REND, "Cannot store descs: Not acting as hs dir");
return RCS_NOTDIR;
}
while (rend_parse_v2_service_descriptor(&parsed, desc_id, &intro_content,
&intro_size, &encoded_size,
&next_desc, current_desc, 1) >= 0) {
number_parsed++;
/* We don't care about the introduction points. */
tor_free(intro_content);
/* For pretty log statements. */
base32_encode(desc_id_base32, sizeof(desc_id_base32),
desc_id, DIGEST_LEN);
/* Is desc ID in the range that we are (directly or indirectly) responsible
* for? */
if (!hid_serv_responsible_for_desc_id(desc_id)) {
log_info(LD_REND, "Service descriptor with desc ID %s is not in "
"interval that we are responsible for.",
safe_str_client(desc_id_base32));
goto skip;
}
/* Is descriptor too old? */
if (parsed->timestamp < now - REND_CACHE_MAX_AGE-REND_CACHE_MAX_SKEW) {
log_info(LD_REND, "Service descriptor with desc ID %s is too old.",
safe_str(desc_id_base32));
goto skip;
}
/* Is descriptor too far in the future? */
if (parsed->timestamp > now + REND_CACHE_MAX_SKEW) {
log_info(LD_REND, "Service descriptor with desc ID %s is too far in the "
"future.",
safe_str(desc_id_base32));
goto skip;
}
/* Do we already have a newer descriptor? */
e = digestmap_get(rend_cache_v2_dir, desc_id);
if (e && e->parsed->timestamp > parsed->timestamp) {
log_info(LD_REND, "We already have a newer service descriptor with the "
"same desc ID %s and version.",
safe_str(desc_id_base32));
goto skip;
}
/* Do we already have this descriptor? */
if (e && !strcmp(desc, e->desc)) {
log_info(LD_REND, "We already have this service descriptor with desc "
"ID %s.", safe_str(desc_id_base32));
goto skip;
}
/* Store received descriptor. */
if (!e) {
e = tor_malloc_zero(sizeof(rend_cache_entry_t));
digestmap_set(rend_cache_v2_dir, desc_id, e);
/* Treat something just uploaded as having been served a little
* while ago, so that flooding with new descriptors doesn't help
* too much.
*/
e->last_served = approx_time() - 3600;
} else {
rend_cache_decrement_allocation(rend_cache_entry_allocation(e));
rend_service_descriptor_free(e->parsed);
tor_free(e->desc);
}
e->parsed = parsed;
e->desc = tor_strndup(current_desc, encoded_size);
e->len = encoded_size;
rend_cache_increment_allocation(rend_cache_entry_allocation(e));
log_info(LD_REND, "Successfully stored service descriptor with desc ID "
"'%s' and len %d.",
safe_str(desc_id_base32), (int)encoded_size);
/* Statistics: Note down this potentially new HS. */
if (options->HiddenServiceStatistics) {
rep_hist_stored_maybe_new_hs(e->parsed->pk);
}
number_stored++;
goto advance;
skip:
rend_service_descriptor_free(parsed);
advance:
/* advance to next descriptor, if available. */
current_desc = next_desc;
/* check if there is a next descriptor. */
if (!current_desc ||
strcmpstart(current_desc, "rendezvous-service-descriptor "))
break;
}
if (!number_parsed) {
log_info(LD_REND, "Could not parse any descriptor.");
return RCS_BADDESC;
}
log_info(LD_REND, "Parsed %d and added %d descriptor%s.",
number_parsed, number_stored, number_stored != 1 ? "s" : "");
return RCS_OKAY;
}
/** Parse the v2 service descriptor in <b>desc</b>, decrypt the included list
* of introduction points with <b>descriptor_cookie</b> (which may also be
* <b>NULL</b> if decryption is not necessary), and store the descriptor to
* the local cache under its version and service id.
*
* If we have a newer v2 descriptor with the same ID, ignore this one.
* If we have an older descriptor with the same ID, replace it.
* If the descriptor's service ID does not match
* <b>rend_query</b>-\>onion_address, reject it.
*
* If the descriptor's descriptor ID doesn't match <b>desc_id_base32</b>,
* reject it.
*
* Return an appropriate rend_cache_store_status_t. If entry is not NULL,
* set it with the cache entry pointer of the descriptor.
*/
rend_cache_store_status_t
rend_cache_store_v2_desc_as_client(const char *desc,
const char *desc_id_base32,
const rend_data_t *rend_query,
rend_cache_entry_t **entry)
{
/*XXXX this seems to have a bit of duplicate code with
* rend_cache_store_v2_desc_as_dir(). Fix that. */
/* Though having similar elements, both functions were separated on
* purpose:
* - dirs don't care about encoded/encrypted introduction points, clients
* do.
* - dirs store descriptors in a separate cache by descriptor ID, whereas
* clients store them by service ID; both caches are different data
* structures and have different access methods.
* - dirs store a descriptor only if they are responsible for its ID,
* clients do so in every way (because they have requested it before).
* - dirs can process multiple concatenated descriptors which is required
* for replication, whereas clients only accept a single descriptor.
* Thus, combining both methods would result in a lot of if statements
* which probably would not improve, but worsen code readability. -KL */
rend_service_descriptor_t *parsed = NULL;
char desc_id[DIGEST_LEN];
char *intro_content = NULL;
size_t intro_size;
size_t encoded_size;
const char *next_desc;
time_t now = time(NULL);
char key[REND_SERVICE_ID_LEN_BASE32+2];
char service_id[REND_SERVICE_ID_LEN_BASE32+1];
char want_desc_id[DIGEST_LEN];
rend_cache_entry_t *e;
rend_cache_store_status_t retval = RCS_BADDESC;
tor_assert(rend_cache);
tor_assert(desc);
tor_assert(desc_id_base32);
memset(want_desc_id, 0, sizeof(want_desc_id));
if (entry) {
*entry = NULL;
}
if (base32_decode(want_desc_id, sizeof(want_desc_id),
desc_id_base32, strlen(desc_id_base32)) != 0) {
log_warn(LD_BUG, "Couldn't decode base32 %s for descriptor id.",
escaped_safe_str_client(desc_id_base32));
goto err;
}
/* Parse the descriptor. */
if (rend_parse_v2_service_descriptor(&parsed, desc_id, &intro_content,
&intro_size, &encoded_size,
&next_desc, desc, 0) < 0) {
log_warn(LD_REND, "Could not parse descriptor.");
goto err;
}
/* Compute service ID from public key. */
if (rend_get_service_id(parsed->pk, service_id)<0) {
log_warn(LD_REND, "Couldn't compute service ID.");
goto err;
}
if (rend_query->onion_address[0] != '\0' &&
strcmp(rend_query->onion_address, service_id)) {
log_warn(LD_REND, "Received service descriptor for service ID %s; "
"expected descriptor for service ID %s.",
service_id, safe_str(rend_query->onion_address));
goto err;
}
if (tor_memneq(desc_id, want_desc_id, DIGEST_LEN)) {
log_warn(LD_REND, "Received service descriptor for %s with incorrect "
"descriptor ID.", service_id);
goto err;
}
/* Decode/decrypt introduction points. */
if (intro_content && intro_size > 0) {
int n_intro_points;
if (rend_query->auth_type != REND_NO_AUTH &&
!tor_mem_is_zero(rend_query->descriptor_cookie,
sizeof(rend_query->descriptor_cookie))) {
char *ipos_decrypted = NULL;
size_t ipos_decrypted_size;
if (rend_decrypt_introduction_points(&ipos_decrypted,
&ipos_decrypted_size,
rend_query->descriptor_cookie,
intro_content,
intro_size) < 0) {
log_warn(LD_REND, "Failed to decrypt introduction points. We are "
"probably unable to parse the encoded introduction points.");
} else {
/* Replace encrypted with decrypted introduction points. */
log_info(LD_REND, "Successfully decrypted introduction points.");
tor_free(intro_content);
intro_content = ipos_decrypted;
intro_size = ipos_decrypted_size;
}
}
n_intro_points = rend_parse_introduction_points(parsed, intro_content,
intro_size);
if (n_intro_points <= 0) {
log_warn(LD_REND, "Failed to parse introduction points. Either the "
"service has published a corrupt descriptor or you have "
"provided invalid authorization data.");
goto err;
} else if (n_intro_points > MAX_INTRO_POINTS) {
log_warn(LD_REND, "Found too many introduction points on a hidden "
"service descriptor for %s. This is probably a (misguided) "
"attempt to improve reliability, but it could also be an "
"attempt to do a guard enumeration attack. Rejecting.",
safe_str_client(service_id));
goto err;
}
} else {
log_info(LD_REND, "Descriptor does not contain any introduction points.");
parsed->intro_nodes = smartlist_new();
}
/* We don't need the encoded/encrypted introduction points any longer. */
tor_free(intro_content);
/* Is descriptor too old? */
if (parsed->timestamp < now - REND_CACHE_MAX_AGE-REND_CACHE_MAX_SKEW) {
log_warn(LD_REND, "Service descriptor with service ID %s is too old.",
safe_str_client(service_id));
goto err;
}
/* Is descriptor too far in the future? */
if (parsed->timestamp > now + REND_CACHE_MAX_SKEW) {
log_warn(LD_REND, "Service descriptor with service ID %s is too far in "
"the future.", safe_str_client(service_id));
goto err;
}
/* Do we already have a newer descriptor? */
tor_snprintf(key, sizeof(key), "2%s", service_id);
e = (rend_cache_entry_t*) strmap_get_lc(rend_cache, key);
if (e && e->parsed->timestamp >= parsed->timestamp) {
log_info(LD_REND, "We already have a new enough service descriptor for "
"service ID %s with the same desc ID and version.",
safe_str_client(service_id));
goto okay;
}
if (!e) {
e = tor_malloc_zero(sizeof(rend_cache_entry_t));
strmap_set_lc(rend_cache, key, e);
} else {
rend_cache_decrement_allocation(rend_cache_entry_allocation(e));
rend_service_descriptor_free(e->parsed);
tor_free(e->desc);
}
e->parsed = parsed;
e->desc = tor_malloc_zero(encoded_size + 1);
strlcpy(e->desc, desc, encoded_size + 1);
e->len = encoded_size;
rend_cache_increment_allocation(rend_cache_entry_allocation(e));
log_debug(LD_REND,"Successfully stored rend desc '%s', len %d.",
safe_str_client(service_id), (int)encoded_size);
if (entry) {
*entry = e;
}
return RCS_OKAY;
okay:
if (entry) {
*entry = e;
}
retval = RCS_OKAY;
err:
rend_service_descriptor_free(parsed);
tor_free(intro_content);
return retval;
}
/** Called when we get a rendezvous-related relay cell on circuit
* <b>circ</b>. Dispatch on rendezvous relay command. */
void
rend_process_relay_cell(circuit_t *circ, const crypt_path_t *layer_hint,
int command, size_t length,
const uint8_t *payload)
{
or_circuit_t *or_circ = NULL;
origin_circuit_t *origin_circ = NULL;
int r = -2;
if (CIRCUIT_IS_ORIGIN(circ)) {
origin_circ = TO_ORIGIN_CIRCUIT(circ);
if (!layer_hint || layer_hint != origin_circ->cpath->prev) {
log_fn(LOG_PROTOCOL_WARN, LD_APP,
"Relay cell (rend purpose %d) from wrong hop on origin circ",
command);
origin_circ = NULL;
}
} else {
or_circ = TO_OR_CIRCUIT(circ);
}
switch (command) {
case RELAY_COMMAND_ESTABLISH_INTRO:
if (or_circ)
r = rend_mid_establish_intro(or_circ,payload,length);
break;
case RELAY_COMMAND_ESTABLISH_RENDEZVOUS:
if (or_circ)
r = rend_mid_establish_rendezvous(or_circ,payload,length);
break;
case RELAY_COMMAND_INTRODUCE1:
if (or_circ)
r = rend_mid_introduce(or_circ,payload,length);
break;
case RELAY_COMMAND_INTRODUCE2:
if (origin_circ)
r = rend_service_introduce(origin_circ,payload,length);
break;
case RELAY_COMMAND_INTRODUCE_ACK:
if (origin_circ)
r = rend_client_introduction_acked(origin_circ,payload,length);
break;
case RELAY_COMMAND_RENDEZVOUS1:
if (or_circ)
r = rend_mid_rendezvous(or_circ,payload,length);
break;
case RELAY_COMMAND_RENDEZVOUS2:
if (origin_circ)
r = rend_client_receive_rendezvous(origin_circ,payload,length);
break;
case RELAY_COMMAND_INTRO_ESTABLISHED:
if (origin_circ)
r = rend_service_intro_established(origin_circ,payload,length);
break;
case RELAY_COMMAND_RENDEZVOUS_ESTABLISHED:
if (origin_circ)
r = rend_client_rendezvous_acked(origin_circ,payload,length);
break;
default:
tor_fragile_assert();
}
if (r == -2)
log_info(LD_PROTOCOL, "Dropping cell (type %d) for wrong circuit type.",
command);
}
/** Allocate and return a new rend_data_t with the same
* contents as <b>query</b>. */
rend_data_t *
rend_data_dup(const rend_data_t *data)
{
tor_assert(data);
return tor_memdup(data, sizeof(rend_data_t));
}
/** Compute descriptor ID for each replicas and save them. A valid onion
* address must be present in the <b>rend_data</b>.
*
* Return 0 on success else -1. */
static int
compute_desc_id(rend_data_t *rend_data)
{
int ret, replica;
time_t now = time(NULL);
tor_assert(rend_data);
/* Compute descriptor ID for each replicas. */
for (replica = 0; replica < ARRAY_LENGTH(rend_data->descriptor_id);
replica++) {
ret = rend_compute_v2_desc_id(rend_data->descriptor_id[replica],
rend_data->onion_address,
rend_data->descriptor_cookie,
now, replica);
if (ret < 0) {
goto end;
}
}
end:
return ret;
}
/** Allocate and initialize a rend_data_t object for a service using the
* given arguments. Only the <b>onion_address</b> is not optional.
*
* Return a valid rend_data_t pointer. */
rend_data_t *
rend_data_service_create(const char *onion_address, const char *pk_digest,
const uint8_t *cookie, rend_auth_type_t auth_type)
{
rend_data_t *rend_data = tor_malloc_zero(sizeof(*rend_data));
/* We need at least one else the call is wrong. */
tor_assert(onion_address != NULL);
if (pk_digest) {
memcpy(rend_data->rend_pk_digest, pk_digest,
sizeof(rend_data->rend_pk_digest));
}
if (cookie) {
memcpy(rend_data->rend_cookie, cookie,
sizeof(rend_data->rend_cookie));
}
strlcpy(rend_data->onion_address, onion_address,
sizeof(rend_data->onion_address));
rend_data->auth_type = auth_type;
return rend_data;
}
/** Allocate and initialize a rend_data_t object for a client request using
* the given arguments. Either an onion address or a descriptor ID is
* needed. Both can be given but only the onion address will be used to make
* the descriptor fetch.
*
* Return a valid rend_data_t pointer or NULL on error meaning the
* descriptor IDs couldn't be computed from the given data. */
rend_data_t *
rend_data_client_create(const char *onion_address, const char *desc_id,
const char *cookie, rend_auth_type_t auth_type)
{
rend_data_t *rend_data = tor_malloc_zero(sizeof(*rend_data));
/* We need at least one else the call is wrong. */
tor_assert(onion_address != NULL || desc_id != NULL);
if (cookie) {
memcpy(rend_data->descriptor_cookie, cookie,
sizeof(rend_data->descriptor_cookie));
}
if (desc_id) {
memcpy(rend_data->desc_id_fetch, desc_id,
sizeof(rend_data->desc_id_fetch));
}
if (onion_address) {
strlcpy(rend_data->onion_address, onion_address,
sizeof(rend_data->onion_address));
if (compute_desc_id(rend_data) < 0) {
goto error;
}
}
rend_data->auth_type = auth_type;
return rend_data;
error:
rend_data_free(rend_data);
return NULL;
}
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