prop224: Load and/or generate v3 service keys

Try to load or/and generate service keys for v3. This write both the public
and private key file to disk along with the hostname file containing the onion
address.

Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit is contained in:
David Goulet 2017-02-01 09:18:58 -05:00
parent f3899acdbf
commit 138e03c488
6 changed files with 215 additions and 33 deletions

View File

@ -1799,7 +1799,7 @@ options_act(const or_options_t *old_options)
monitor_owning_controller_process(options->OwningControllerProcess);
/* reload keys as needed for rendezvous services. */
if (rend_service_load_all_keys(NULL)<0) {
if (hs_service_load_all_keys() < 0) {
log_warn(LD_GENERAL,"Error loading rendezvous service keys");
return -1;
}

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@ -20,6 +20,20 @@
#include "hs_service.h"
#include "rendcommon.h"
/* Allocate and return a string containing the path to filename in directory.
* This function will never return NULL. The caller must free this path. */
char *
hs_path_from_filename(const char *directory, const char *filename)
{
char *file_path = NULL;
tor_assert(directory);
tor_assert(filename);
tor_asprintf(&file_path, "%s%s%s", directory, PATH_SEPARATOR, filename);
return file_path;
}
/* Make sure that the directory for <b>service</b> is private, using the config
* <b>username</b>.
* If <b>create</b> is true:

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@ -88,6 +88,7 @@ void hs_free_all(void);
int hs_check_service_private_dir(const char *username, const char *path,
unsigned int dir_group_readable,
unsigned int create);
char *hs_path_from_filename(const char *directory, const char *filename);
void hs_build_address(const ed25519_public_key_t *key, uint8_t version,
char *addr_out);
int hs_address_is_valid(const char *address);

View File

@ -12,6 +12,7 @@
#include "relay.h"
#include "rendservice.h"
#include "router.h"
#include "routerkeys.h"
#include "hs_common.h"
#include "hs_config.h"
@ -21,6 +22,11 @@
#include "hs/cell_establish_intro.h"
#include "hs/cell_common.h"
/* Onion service directory file names. */
static const char *fname_keyfile_prefix = "hs_ed25519";
static const char *fname_hostname = "hostname";
static const char *address_tld = "onion";
/* Staging list of service object. When configuring service, we add them to
* this list considered a staging area and they will get added to our global
* map once the keys have been loaded. These two steps are seperated because
@ -163,19 +169,21 @@ ht_free_service_(struct hs_service_t *service, void *data)
static void
service_free_all(void)
{
if (hs_service_map == NULL) {
return;
if (hs_service_map) {
/* The free helper function returns 1 so this is safe. */
hs_service_ht_HT_FOREACH_FN(hs_service_map, ht_free_service_, NULL);
HT_CLEAR(hs_service_ht, hs_service_map);
tor_free(hs_service_map);
hs_service_map = NULL;
}
if (hs_service_staging_list) {
/* Cleanup staging list. */
SMARTLIST_FOREACH(hs_service_staging_list, hs_service_t *, s,
hs_service_free(s));
smartlist_free(hs_service_staging_list);
hs_service_staging_list = NULL;
}
/* The free helper function returns 1 so this is safe. */
hs_service_ht_HT_FOREACH_FN(hs_service_map, ht_free_service_, NULL);
HT_CLEAR(hs_service_ht, hs_service_map);
tor_free(hs_service_map);
hs_service_map = NULL;
/* Cleanup staging list. */
SMARTLIST_FOREACH(hs_service_staging_list, hs_service_t *, s,
hs_service_free(s));
smartlist_free(hs_service_staging_list);
hs_service_staging_list = NULL;
}
/* Close all rendezvous circuits for the given service. */
@ -299,19 +307,29 @@ move_ephemeral_services(hs_service_ht *src, hs_service_ht *dst)
}
}
/* Register services that are in the list. Once this function returns, the
* global service map will be set with the right content and all non surviving
* services will be cleaned up. */
void
hs_service_register_services(smartlist_t *new_service_list)
/* Return a const string of the directory path escaped. If this is an
* ephemeral service, it returns "[EPHEMERAL]". This can only be called from
* the main thread because escaped() uses a static variable. */
static const char *
service_escaped_dir(const hs_service_t *s)
{
return (s->config.is_ephemeral) ? "[EPHEMERAL]" :
escaped(s->config.directory_path);
}
/* Register services that are in the staging list. Once this function returns,
* the global service map will be set with the right content and all non
* surviving services will be cleaned up. */
static void
register_all_services(void)
{
struct hs_service_ht *new_service_map;
hs_service_t *s, **iter;
tor_assert(new_service_list);
tor_assert(hs_service_staging_list);
/* We'll save us some allocation and computing time. */
if (smartlist_len(new_service_list) == 0) {
if (smartlist_len(hs_service_staging_list) == 0) {
return;
}
@ -325,7 +343,7 @@ hs_service_register_services(smartlist_t *new_service_list)
* port or stopping the tor daemon. */
move_ephemeral_services(hs_service_map, new_service_map);
SMARTLIST_FOREACH_BEGIN(new_service_list, hs_service_t *, snew) {
SMARTLIST_FOREACH_BEGIN(hs_service_staging_list, hs_service_t *, snew) {
/* Check if that service is already in our global map and if so, we'll
* transfer the intro points to it. */
s = find_service(hs_service_map, &snew->keys.identity_pk);
@ -345,8 +363,8 @@ hs_service_register_services(smartlist_t *new_service_list)
* service means we failed to validate correctly. In that case, don't
* break tor and ignore the service but tell user. */
log_warn(LD_BUG, "Unable to register service with directory %s",
snew->config.directory_path);
SMARTLIST_DEL_CURRENT(new_service_list, snew);
service_escaped_dir(snew));
SMARTLIST_DEL_CURRENT(hs_service_staging_list, snew);
hs_service_free(snew);
}
} SMARTLIST_FOREACH_END(snew);
@ -357,11 +375,162 @@ hs_service_register_services(smartlist_t *new_service_list)
close_service_circuits(*iter);
}
/* Time to make the switch. We'll wipe the current list and switch. */
/* Time to make the switch. We'll clear the staging list because its content
* has now changed ownership to the map. */
smartlist_clear(hs_service_staging_list);
service_free_all();
hs_service_map = new_service_map;
}
/* Write the onion address of a given service to the given filename fname_ in
* the service directory. Return 0 on success else -1 on error. */
static int
write_address_to_file(const hs_service_t *service, const char *fname_)
{
int ret = -1;
char *fname = NULL;
/* Length of an address plus the sizeof the address tld (onion) which counts
* the NUL terminated byte so we keep it for the "." and the newline. */
char buf[HS_SERVICE_ADDR_LEN_BASE32 + sizeof(address_tld) + 1];
tor_assert(service);
tor_assert(fname_);
/* Construct the full address with the onion tld and write the hostname file
* to disk. */
tor_snprintf(buf, sizeof(buf), "%s.%s\n", service->onion_address,
address_tld);
/* Notice here that we use the given "fname_". */
fname = hs_path_from_filename(service->config.directory_path, fname_);
if (write_str_to_file(fname, buf, 0) < 0) {
log_warn(LD_REND, "Could not write onion address to hostname file %s",
escaped(fname));
goto end;
}
#ifndef _WIN32
if (service->config.dir_group_readable) {
/* Mode to 0640. */
if (chmod(fname, S_IRUSR | S_IWUSR | S_IRGRP) < 0) {
log_warn(LD_FS, "Unable to make onion service hostname file %s "
"group-readable.", escaped(fname));
}
}
#endif /* _WIN32 */
/* Success. */
ret = 0;
end:
tor_free(fname);
return ret;
}
/* Load and/or generate private keys for the given service. On success, the
* hostname file will be written to disk along with the master private key iff
* the service is not configured for offline keys. Return 0 on success else -1
* on failure. */
static int
load_service_keys(hs_service_t *service)
{
int ret = -1;
char *fname = NULL;
ed25519_keypair_t *kp;
const hs_service_config_t *config;
tor_assert(service);
config = &service->config;
/* Create and fix permission on service directory. We are about to write
* files to that directory so make sure it exists and has the right
* permissions. We do this here because at this stage we know that Tor is
* actually running and the service we have has been validated. */
if (BUG(hs_check_service_private_dir(get_options()->User,
config->directory_path,
config->dir_group_readable, 1) < 0)) {
goto end;
}
/* Try to load the keys from file or generate it if not found. */
fname = hs_path_from_filename(config->directory_path, fname_keyfile_prefix);
/* Don't ask for key creation, we want to know if we were able to load it or
* we had to generate it. Better logging! */
kp = ed_key_init_from_file(fname, 0, LOG_INFO, NULL, 0, 0, 0, NULL);
if (!kp) {
log_info(LD_REND, "Unable to load keys from %s. Generating it...", fname);
/* We'll now try to generate the keys and for it we want the strongest
* randomness for it. The keypair will be written in different files. */
uint32_t key_flags = INIT_ED_KEY_CREATE | INIT_ED_KEY_EXTRA_STRONG |
INIT_ED_KEY_SPLIT;
kp = ed_key_init_from_file(fname, key_flags, LOG_WARN, NULL, 0, 0, 0,
NULL);
if (!kp) {
log_warn(LD_REND, "Unable to generate keys and save in %s.", fname);
goto end;
}
}
/* Copy loaded or generated keys to service object. */
ed25519_pubkey_copy(&service->keys.identity_pk, &kp->pubkey);
memcpy(&service->keys.identity_sk, &kp->seckey,
sizeof(service->keys.identity_sk));
/* This does a proper memory wipe. */
ed25519_keypair_free(kp);
/* Build onion address from the newly loaded keys. */
tor_assert(service->version <= UINT8_MAX);
hs_build_address(&service->keys.identity_pk, (uint8_t) service->version,
service->onion_address);
/* Write onion address to hostname file. */
if (write_address_to_file(service, fname_hostname) < 0) {
goto end;
}
/* Succes. */
ret = 0;
end:
tor_free(fname);
return ret;
}
/* Load and/or generate keys for all onion services including the client
* authorization if any. Return 0 on success, -1 on failure. */
int
hs_service_load_all_keys(void)
{
/* Load v2 service keys if we have v2. */
if (num_rend_services() != 0) {
if (rend_service_load_all_keys(NULL) < 0) {
goto err;
}
}
/* Load or/and generate them for v3+. */
SMARTLIST_FOREACH_BEGIN(hs_service_staging_list, hs_service_t *, service) {
/* Ignore ephemeral service, they already have their keys set. */
if (service->config.is_ephemeral) {
continue;
}
log_info(LD_REND, "Loading v3 onion service keys from %s",
service_escaped_dir(service));
if (load_service_keys(service) < 0) {
goto err;
}
/* XXX: Load/Generate client authorization keys. (#20700) */
} SMARTLIST_FOREACH_END(service);
/* Final step, the staging list contains service in a quiescent state that
* is ready to be used. Register them to the global map. Once this is over,
* the staging list will be cleaned up. */
register_all_services();
/* All keys have been loaded successfully. */
return 0;
err:
return -1;
}
/* Put all service object in the given service list. After this, the caller
* looses ownership of every elements in the list and responsible to free the
* list pointer. */

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@ -13,6 +13,7 @@
#include "crypto_ed25519.h"
#include "replaycache.h"
#include "hs_common.h"
#include "hs_descriptor.h"
#include "hs_intropoint.h"
@ -172,6 +173,10 @@ typedef struct hs_service_t {
/* Protocol version of the service. Specified by HiddenServiceVersion. */
uint32_t version;
/* Onion address base32 encoded and NUL terminated. We keep it for logging
* purposes so we don't have to build it everytime. */
char onion_address[HS_SERVICE_ADDR_LEN_BASE32 + 1];
/* Hashtable node: use to look up the service by its master public identity
* key in the service global map. */
HT_ENTRY(hs_service_t) hs_service_node;
@ -205,8 +210,8 @@ void hs_service_free_all(void);
hs_service_t *hs_service_new(const or_options_t *options);
void hs_service_free(hs_service_t *service);
void hs_service_register_services(smartlist_t *new_service_list);
void hs_service_stage_services(const smartlist_t *service_list);
int hs_service_load_all_keys(void);
/* These functions are only used by unit tests and we need to expose them else
* hs_service.o ends up with no symbols in libor.a which makes clang throw a

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@ -1046,15 +1046,8 @@ rend_service_update_descriptor(rend_service_t *service)
static char *
rend_service_path(const rend_service_t *service, const char *file_name)
{
char *file_path = NULL;
tor_assert(service->directory);
/* Can never fail: asserts rather than leaving file_path NULL. */
tor_asprintf(&file_path, "%s%s%s",
service->directory, PATH_SEPARATOR, file_name);
return file_path;
return hs_path_from_filename(service->directory, file_name);
}
/* Allocate and return a string containing the path to the single onion