tomato-testing/toxcore/onion.c
Green Sky 9ace11a0e2 Squashed 'external/toxcore/c-toxcore/' changes from f1df709b87..8f0d505f9a
8f0d505f9a feat: add ngc events
9b8216e70c refactor: Make event dispatch ordered by receive time.
814c12a6f4 cleanup: Add dynamically derived array sizes to the API.
226b23be12 cleanup: Add explicit array sizes to toxencryptsave.
ef33cb4de0 cleanup: Add Toxav alias for ToxAV.
1da723b34d cleanup: Make Tox_Options a typedef.
b148a2afff chore: Simplify msvc build using vcpkg.
5cac6d7eb1 cleanup: Move `tox_get_system` out of the public API.
c9ca4007e3 refactor: Align group message sending with other send functions.
6c6c0b1b1b cleanup: Make setters take non-const `Tox *`.
a76f758d70 cleanup: Mark arrays in the tox API as `[]` instead of `*`.
baf6d1f6cf cleanup: Make array params in toxav `[]` instead of `*`.
79f55bd06a cleanup: Put the size of fixed arrays into the API types.
1e73698db2 cleanup: Add typedefs for public API int identifiers.
cac074c57f chore: Add fetch-sha256 script to update bootstrap node hash.
32576656bb Make the comment capitalization uniform
aff4dda17c Spellcheck tox-bootstrapd
40b5fbbe9d chore: Remove settings.yml in favour of hs-github-tools.
ebafd51be7 chore: Use GPL license with https.
0e42752f0f cleanup: Move all vptr-to-ptr casts to the beginning of a function.
5407384211 cleanup: Use github actions matrix to simplify CI.
82d8265688 fix: Use QueryPerformanceCounter on windows for monotonic time.
1224e656e3 chore: Add `net_(new|kill)_strerror` to cppcheck's allocators.
6a90ddfe4e cleanup: Run clang-tidy on headers, as well.
bd930cc80a cleanup: Make TCP connection failures a warning instead of error.
fad6e4e173 cleanup: Make all .c files include the headers they need.
ef4897a898 cleanup: Upgrade to clang-tidy-17 and fix some warnings.
REVERT: f1df709b87 feat: add ngc events
REVERT: 1b6c907235 refactor: Make event dispatch ordered by receive time.

git-subtree-dir: external/toxcore/c-toxcore
git-subtree-split: 8f0d505f9a598cc41c682178e1589bcc01efe9cb
2024-01-09 16:39:05 +01:00

781 lines
25 KiB
C

/* SPDX-License-Identifier: GPL-3.0-or-later
* Copyright © 2016-2018 The TokTok team.
* Copyright © 2013 Tox project.
*/
/**
* Implementation of the onion part of docs/Prevent_Tracking.txt
*/
#include "onion.h"
#include <assert.h>
#include <string.h>
#include "DHT.h"
#include "ccompat.h"
#include "crypto_core.h"
#include "logger.h"
#include "mem.h"
#include "mono_time.h"
#include "network.h"
#include "shared_key_cache.h"
#define RETURN_1 ONION_RETURN_1
#define RETURN_2 ONION_RETURN_2
#define RETURN_3 ONION_RETURN_3
#define SEND_BASE ONION_SEND_BASE
#define SEND_3 ONION_SEND_3
#define SEND_2 ONION_SEND_2
#define SEND_1 ONION_SEND_1
#define KEY_REFRESH_INTERVAL (2 * 60 * 60)
// Settings for the shared key cache
#define MAX_KEYS_PER_SLOT 4
#define KEYS_TIMEOUT 600
/** Change symmetric keys every 2 hours to make paths expire eventually. */
non_null()
static void change_symmetric_key(Onion *onion)
{
if (mono_time_is_timeout(onion->mono_time, onion->timestamp, KEY_REFRESH_INTERVAL)) {
new_symmetric_key(onion->rng, onion->secret_symmetric_key);
onion->timestamp = mono_time_get(onion->mono_time);
}
}
/** packing and unpacking functions */
non_null()
static void ip_pack(uint8_t *data, const IP *source)
{
data[0] = source->family.value;
if (net_family_is_ipv4(source->family) || net_family_is_tox_tcp_ipv4(source->family)) {
memset(data + 1, 0, SIZE_IP6);
memcpy(data + 1, source->ip.v4.uint8, SIZE_IP4);
} else {
memcpy(data + 1, source->ip.v6.uint8, SIZE_IP6);
}
}
/** return 0 on success, -1 on failure. */
non_null()
static int ip_unpack(IP *target, const uint8_t *data, unsigned int data_size, bool disable_family_check)
{
if (data_size < (1 + SIZE_IP6)) {
return -1;
}
// TODO(iphydf): Validate input.
target->family.value = data[0];
if (net_family_is_ipv4(target->family) || net_family_is_tox_tcp_ipv4(target->family)) {
memcpy(target->ip.v4.uint8, data + 1, SIZE_IP4);
} else {
memcpy(target->ip.v6.uint8, data + 1, SIZE_IP6);
}
const bool valid = disable_family_check ||
net_family_is_ipv4(target->family) ||
net_family_is_ipv6(target->family);
return valid ? 0 : -1;
}
non_null()
static void ipport_pack(uint8_t *data, const IP_Port *source)
{
ip_pack(data, &source->ip);
memcpy(data + SIZE_IP, &source->port, SIZE_PORT);
}
/** return 0 on success, -1 on failure. */
non_null()
static int ipport_unpack(IP_Port *target, const uint8_t *data, unsigned int data_size, bool disable_family_check)
{
if (data_size < (SIZE_IP + SIZE_PORT)) {
return -1;
}
if (ip_unpack(&target->ip, data, data_size, disable_family_check) == -1) {
return -1;
}
memcpy(&target->port, data + SIZE_IP, SIZE_PORT);
return 0;
}
/** @brief Create a new onion path.
*
* Create a new onion path out of nodes (nodes is a list of ONION_PATH_LENGTH nodes)
*
* new_path must be an empty memory location of at least Onion_Path size.
*
* return -1 on failure.
* return 0 on success.
*/
int create_onion_path(const Random *rng, const DHT *dht, Onion_Path *new_path, const Node_format *nodes)
{
if (new_path == nullptr || nodes == nullptr) {
return -1;
}
encrypt_precompute(nodes[0].public_key, dht_get_self_secret_key(dht), new_path->shared_key1);
memcpy(new_path->public_key1, dht_get_self_public_key(dht), CRYPTO_PUBLIC_KEY_SIZE);
uint8_t random_public_key[CRYPTO_PUBLIC_KEY_SIZE];
uint8_t random_secret_key[CRYPTO_SECRET_KEY_SIZE];
crypto_new_keypair(rng, random_public_key, random_secret_key);
encrypt_precompute(nodes[1].public_key, random_secret_key, new_path->shared_key2);
memcpy(new_path->public_key2, random_public_key, CRYPTO_PUBLIC_KEY_SIZE);
crypto_new_keypair(rng, random_public_key, random_secret_key);
encrypt_precompute(nodes[2].public_key, random_secret_key, new_path->shared_key3);
memcpy(new_path->public_key3, random_public_key, CRYPTO_PUBLIC_KEY_SIZE);
crypto_memzero(random_secret_key, sizeof(random_secret_key));
new_path->ip_port1 = nodes[0].ip_port;
new_path->ip_port2 = nodes[1].ip_port;
new_path->ip_port3 = nodes[2].ip_port;
memcpy(new_path->node_public_key1, nodes[0].public_key, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(new_path->node_public_key2, nodes[1].public_key, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(new_path->node_public_key3, nodes[2].public_key, CRYPTO_PUBLIC_KEY_SIZE);
return 0;
}
/** @brief Dump nodes in onion path to nodes of length num_nodes.
*
* return -1 on failure.
* return 0 on success.
*/
int onion_path_to_nodes(Node_format *nodes, unsigned int num_nodes, const Onion_Path *path)
{
if (num_nodes < ONION_PATH_LENGTH) {
return -1;
}
nodes[0].ip_port = path->ip_port1;
nodes[1].ip_port = path->ip_port2;
nodes[2].ip_port = path->ip_port3;
memcpy(nodes[0].public_key, path->node_public_key1, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(nodes[1].public_key, path->node_public_key2, CRYPTO_PUBLIC_KEY_SIZE);
memcpy(nodes[2].public_key, path->node_public_key3, CRYPTO_PUBLIC_KEY_SIZE);
return 0;
}
/** @brief Create a onion packet.
*
* Use Onion_Path path to create packet for data of length to dest.
* Maximum length of data is ONION_MAX_DATA_SIZE.
* packet should be at least ONION_MAX_PACKET_SIZE big.
*
* return -1 on failure.
* return length of created packet on success.
*/
int create_onion_packet(const Random *rng, uint8_t *packet, uint16_t max_packet_length,
const Onion_Path *path, const IP_Port *dest,
const uint8_t *data, uint16_t length)
{
if (1 + length + SEND_1 > max_packet_length || length == 0) {
return -1;
}
VLA(uint8_t, step1, SIZE_IPPORT + length);
ipport_pack(step1, dest);
memcpy(step1 + SIZE_IPPORT, data, length);
uint8_t nonce[CRYPTO_NONCE_SIZE];
random_nonce(rng, nonce);
VLA(uint8_t, step2, SIZE_IPPORT + SEND_BASE + length);
ipport_pack(step2, &path->ip_port3);
memcpy(step2 + SIZE_IPPORT, path->public_key3, CRYPTO_PUBLIC_KEY_SIZE);
int len = encrypt_data_symmetric(path->shared_key3, nonce, step1, SIZEOF_VLA(step1),
step2 + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + length + CRYPTO_MAC_SIZE) {
return -1;
}
VLA(uint8_t, step3, SIZE_IPPORT + SEND_BASE * 2 + length);
ipport_pack(step3, &path->ip_port2);
memcpy(step3 + SIZE_IPPORT, path->public_key2, CRYPTO_PUBLIC_KEY_SIZE);
len = encrypt_data_symmetric(path->shared_key2, nonce, step2, SIZEOF_VLA(step2),
step3 + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + SEND_BASE + length + CRYPTO_MAC_SIZE) {
return -1;
}
packet[0] = NET_PACKET_ONION_SEND_INITIAL;
memcpy(packet + 1, nonce, CRYPTO_NONCE_SIZE);
memcpy(packet + 1 + CRYPTO_NONCE_SIZE, path->public_key1, CRYPTO_PUBLIC_KEY_SIZE);
len = encrypt_data_symmetric(path->shared_key1, nonce, step3, SIZEOF_VLA(step3),
packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + SEND_BASE * 2 + length + CRYPTO_MAC_SIZE) {
return -1;
}
return 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + len;
}
/** @brief Create a onion packet to be sent over tcp.
*
* Use Onion_Path path to create packet for data of length to dest.
* Maximum length of data is ONION_MAX_DATA_SIZE.
* packet should be at least ONION_MAX_PACKET_SIZE big.
*
* return -1 on failure.
* return length of created packet on success.
*/
int create_onion_packet_tcp(const Random *rng, uint8_t *packet, uint16_t max_packet_length,
const Onion_Path *path, const IP_Port *dest,
const uint8_t *data, uint16_t length)
{
if (CRYPTO_NONCE_SIZE + SIZE_IPPORT + SEND_BASE * 2 + length > max_packet_length || length == 0) {
return -1;
}
VLA(uint8_t, step1, SIZE_IPPORT + length);
ipport_pack(step1, dest);
memcpy(step1 + SIZE_IPPORT, data, length);
uint8_t nonce[CRYPTO_NONCE_SIZE];
random_nonce(rng, nonce);
VLA(uint8_t, step2, SIZE_IPPORT + SEND_BASE + length);
ipport_pack(step2, &path->ip_port3);
memcpy(step2 + SIZE_IPPORT, path->public_key3, CRYPTO_PUBLIC_KEY_SIZE);
int len = encrypt_data_symmetric(path->shared_key3, nonce, step1, SIZEOF_VLA(step1),
step2 + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + length + CRYPTO_MAC_SIZE) {
return -1;
}
ipport_pack(packet + CRYPTO_NONCE_SIZE, &path->ip_port2);
memcpy(packet + CRYPTO_NONCE_SIZE + SIZE_IPPORT, path->public_key2, CRYPTO_PUBLIC_KEY_SIZE);
len = encrypt_data_symmetric(path->shared_key2, nonce, step2, SIZEOF_VLA(step2),
packet + CRYPTO_NONCE_SIZE + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE);
if (len != SIZE_IPPORT + SEND_BASE + length + CRYPTO_MAC_SIZE) {
return -1;
}
memcpy(packet, nonce, CRYPTO_NONCE_SIZE);
return CRYPTO_NONCE_SIZE + SIZE_IPPORT + CRYPTO_PUBLIC_KEY_SIZE + len;
}
/** @brief Create and send a onion response sent initially to dest with.
* Maximum length of data is ONION_RESPONSE_MAX_DATA_SIZE.
*
* return -1 on failure.
* return 0 on success.
*/
int send_onion_response(const Logger *log, const Networking_Core *net,
const IP_Port *dest, const uint8_t *data, uint16_t length,
const uint8_t *ret)
{
if (length > ONION_RESPONSE_MAX_DATA_SIZE || length == 0) {
return -1;
}
const uint16_t packet_size = 1 + RETURN_3 + length;
VLA(uint8_t, packet, packet_size);
packet[0] = NET_PACKET_ONION_RECV_3;
memcpy(packet + 1, ret, RETURN_3);
memcpy(packet + 1 + RETURN_3, data, length);
if ((uint16_t)sendpacket(net, dest, packet, packet_size) != packet_size) {
return -1;
}
Ip_Ntoa ip_str;
LOGGER_TRACE(log, "forwarded onion RECV_3 to %s:%d (%02x in %02x, %d bytes)",
net_ip_ntoa(&dest->ip, &ip_str), net_ntohs(dest->port), data[0], packet[0], packet_size);
return 0;
}
non_null()
static int handle_send_initial(void *object, const IP_Port *source, const uint8_t *packet, uint16_t length,
void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
LOGGER_TRACE(onion->log, "invalid initial onion packet length: %u (max: %u)",
length, ONION_MAX_PACKET_SIZE);
return 1;
}
if (length <= 1 + SEND_1) {
LOGGER_TRACE(onion->log, "initial onion packet cannot contain SEND_1 packet: %u <= %u",
length, 1 + SEND_1);
return 1;
}
change_symmetric_key(onion);
const int nonce_start = 1;
const int public_key_start = nonce_start + CRYPTO_NONCE_SIZE;
const int ciphertext_start = public_key_start + CRYPTO_PUBLIC_KEY_SIZE;
const int ciphertext_length = length - ciphertext_start;
const int plaintext_length = ciphertext_length - CRYPTO_MAC_SIZE;
uint8_t plain[ONION_MAX_PACKET_SIZE];
const uint8_t *public_key = &packet[public_key_start];
const uint8_t *shared_key = shared_key_cache_lookup(onion->shared_keys_1, public_key);
if (shared_key == nullptr) {
/* Error looking up/deriving the shared key */
LOGGER_TRACE(onion->log, "shared onion key lookup failed for pk %02x%02x...",
public_key[0], public_key[1]);
return 1;
}
const int len = decrypt_data_symmetric(
shared_key, &packet[nonce_start], &packet[ciphertext_start], ciphertext_length, plain);
if (len != plaintext_length) {
LOGGER_TRACE(onion->log, "decrypt failed: %d != %d", len, plaintext_length);
return 1;
}
return onion_send_1(onion, plain, len, source, packet + 1);
}
int onion_send_1(const Onion *onion, const uint8_t *plain, uint16_t len, const IP_Port *source, const uint8_t *nonce)
{
const uint16_t max_len = ONION_MAX_PACKET_SIZE + SIZE_IPPORT - (1 + CRYPTO_NONCE_SIZE + ONION_RETURN_1);
if (len > max_len) {
LOGGER_TRACE(onion->log, "invalid SEND_1 length: %d > %d", len, max_len);
return 1;
}
if (len <= SIZE_IPPORT + SEND_BASE * 2) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, false) == -1) {
return 1;
}
uint8_t ip_port[SIZE_IPPORT];
ipport_pack(ip_port, source);
uint8_t data[ONION_MAX_PACKET_SIZE] = {0};
data[0] = NET_PACKET_ONION_SEND_1;
memcpy(data + 1, nonce, CRYPTO_NONCE_SIZE);
memcpy(data + 1 + CRYPTO_NONCE_SIZE, plain + SIZE_IPPORT, len - SIZE_IPPORT);
uint16_t data_len = 1 + CRYPTO_NONCE_SIZE + (len - SIZE_IPPORT);
uint8_t *ret_part = data + data_len;
random_nonce(onion->rng, ret_part);
len = encrypt_data_symmetric(onion->secret_symmetric_key, ret_part, ip_port, SIZE_IPPORT,
ret_part + CRYPTO_NONCE_SIZE);
if (len != SIZE_IPPORT + CRYPTO_MAC_SIZE) {
return 1;
}
data_len += CRYPTO_NONCE_SIZE + len;
if ((uint32_t)sendpacket(onion->net, &send_to, data, data_len) != data_len) {
return 1;
}
Ip_Ntoa ip_str;
LOGGER_TRACE(onion->log, "forwarded onion packet to %s:%d, level 1 (%02x in %02x, %d bytes)",
net_ip_ntoa(&send_to.ip, &ip_str), net_ntohs(send_to.port), plain[0], data[0], data_len);
return 0;
}
non_null()
static int handle_send_1(void *object, const IP_Port *source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + SEND_2) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[ONION_MAX_PACKET_SIZE];
const uint8_t *public_key = packet + 1 + CRYPTO_NONCE_SIZE;
const uint8_t *shared_key = shared_key_cache_lookup(onion->shared_keys_2, public_key);
if (shared_key == nullptr) {
/* Error looking up/deriving the shared key */
return 1;
}
int len = decrypt_data_symmetric(shared_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE,
length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_1), plain);
if (len != length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_1 + CRYPTO_MAC_SIZE)) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, false) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE] = {0};
data[0] = NET_PACKET_ONION_SEND_2;
memcpy(data + 1, packet + 1, CRYPTO_NONCE_SIZE);
memcpy(data + 1 + CRYPTO_NONCE_SIZE, plain + SIZE_IPPORT, len - SIZE_IPPORT);
uint16_t data_len = 1 + CRYPTO_NONCE_SIZE + (len - SIZE_IPPORT);
uint8_t *ret_part = data + data_len;
random_nonce(onion->rng, ret_part);
uint8_t ret_data[RETURN_1 + SIZE_IPPORT];
ipport_pack(ret_data, source);
memcpy(ret_data + SIZE_IPPORT, packet + (length - RETURN_1), RETURN_1);
len = encrypt_data_symmetric(onion->secret_symmetric_key, ret_part, ret_data, sizeof(ret_data),
ret_part + CRYPTO_NONCE_SIZE);
if (len != RETURN_2 - CRYPTO_NONCE_SIZE) {
return 1;
}
data_len += CRYPTO_NONCE_SIZE + len;
if ((uint32_t)sendpacket(onion->net, &send_to, data, data_len) != data_len) {
return 1;
}
Ip_Ntoa ip_str;
LOGGER_TRACE(onion->log, "forwarded onion packet to %s:%d, level 2 (%02x in %02x, %d bytes)",
net_ip_ntoa(&send_to.ip, &ip_str), net_ntohs(send_to.port), packet[0], data[0], data_len);
return 0;
}
non_null()
static int handle_send_2(void *object, const IP_Port *source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + SEND_3) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[ONION_MAX_PACKET_SIZE];
const uint8_t *public_key = packet + 1 + CRYPTO_NONCE_SIZE;
const uint8_t *shared_key = shared_key_cache_lookup(onion->shared_keys_3, public_key);
if (shared_key == nullptr) {
/* Error looking up/deriving the shared key */
return 1;
}
int len = decrypt_data_symmetric(shared_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE,
length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_2), plain);
if (len != length - (1 + CRYPTO_NONCE_SIZE + CRYPTO_PUBLIC_KEY_SIZE + RETURN_2 + CRYPTO_MAC_SIZE)) {
return 1;
}
assert(len > SIZE_IPPORT);
const uint8_t packet_id = plain[SIZE_IPPORT];
if (packet_id != NET_PACKET_ANNOUNCE_REQUEST && packet_id != NET_PACKET_ANNOUNCE_REQUEST_OLD &&
packet_id != NET_PACKET_ONION_DATA_REQUEST) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, false) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE] = {0};
memcpy(data, plain + SIZE_IPPORT, len - SIZE_IPPORT);
uint16_t data_len = len - SIZE_IPPORT;
uint8_t *ret_part = data + (len - SIZE_IPPORT);
random_nonce(onion->rng, ret_part);
uint8_t ret_data[RETURN_2 + SIZE_IPPORT];
ipport_pack(ret_data, source);
memcpy(ret_data + SIZE_IPPORT, packet + (length - RETURN_2), RETURN_2);
len = encrypt_data_symmetric(onion->secret_symmetric_key, ret_part, ret_data, sizeof(ret_data),
ret_part + CRYPTO_NONCE_SIZE);
if (len != RETURN_3 - CRYPTO_NONCE_SIZE) {
return 1;
}
data_len += RETURN_3;
if ((uint32_t)sendpacket(onion->net, &send_to, data, data_len) != data_len) {
return 1;
}
Ip_Ntoa ip_str;
LOGGER_TRACE(onion->log, "forwarded onion packet to %s:%d, level 3 (%02x in %02x, %d bytes)",
net_ip_ntoa(&send_to.ip, &ip_str), net_ntohs(send_to.port), packet[0], data[0], data_len);
return 0;
}
non_null()
static int handle_recv_3(void *object, const IP_Port *source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + RETURN_3) {
return 1;
}
const uint8_t packet_id = packet[1 + RETURN_3];
if (packet_id != NET_PACKET_ANNOUNCE_RESPONSE && packet_id != NET_PACKET_ANNOUNCE_RESPONSE_OLD &&
packet_id != NET_PACKET_ONION_DATA_RESPONSE) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[SIZE_IPPORT + RETURN_2];
const int len = decrypt_data_symmetric(onion->secret_symmetric_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE,
SIZE_IPPORT + RETURN_2 + CRYPTO_MAC_SIZE, plain);
if ((uint32_t)len != sizeof(plain)) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, false) == -1) {
LOGGER_DEBUG(onion->log, "failed to unpack IP/Port");
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE] = {0};
data[0] = NET_PACKET_ONION_RECV_2;
memcpy(data + 1, plain + SIZE_IPPORT, RETURN_2);
memcpy(data + 1 + RETURN_2, packet + 1 + RETURN_3, length - (1 + RETURN_3));
const uint16_t data_len = 1 + RETURN_2 + (length - (1 + RETURN_3));
if ((uint32_t)sendpacket(onion->net, &send_to, data, data_len) != data_len) {
return 1;
}
Ip_Ntoa ip_str;
LOGGER_TRACE(onion->log, "forwarded onion RECV_2 to %s:%d (%02x in %02x, %d bytes)",
net_ip_ntoa(&send_to.ip, &ip_str), net_ntohs(send_to.port), packet[0], data[0], data_len);
return 0;
}
non_null()
static int handle_recv_2(void *object, const IP_Port *source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + RETURN_2) {
return 1;
}
const uint8_t packet_id = packet[1 + RETURN_2];
if (packet_id != NET_PACKET_ANNOUNCE_RESPONSE && packet_id != NET_PACKET_ANNOUNCE_RESPONSE_OLD &&
packet_id != NET_PACKET_ONION_DATA_RESPONSE) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[SIZE_IPPORT + RETURN_1];
const int len = decrypt_data_symmetric(onion->secret_symmetric_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE,
SIZE_IPPORT + RETURN_1 + CRYPTO_MAC_SIZE, plain);
if ((uint32_t)len != sizeof(plain)) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, false) == -1) {
return 1;
}
uint8_t data[ONION_MAX_PACKET_SIZE] = {0};
data[0] = NET_PACKET_ONION_RECV_1;
memcpy(data + 1, plain + SIZE_IPPORT, RETURN_1);
memcpy(data + 1 + RETURN_1, packet + 1 + RETURN_2, length - (1 + RETURN_2));
const uint16_t data_len = 1 + RETURN_1 + (length - (1 + RETURN_2));
if ((uint32_t)sendpacket(onion->net, &send_to, data, data_len) != data_len) {
return 1;
}
Ip_Ntoa ip_str;
LOGGER_TRACE(onion->log, "forwarded onion RECV_1 to %s:%d (%02x in %02x, %d bytes)",
net_ip_ntoa(&send_to.ip, &ip_str), net_ntohs(send_to.port), packet[0], data[0], data_len);
return 0;
}
non_null()
static int handle_recv_1(void *object, const IP_Port *source, const uint8_t *packet, uint16_t length, void *userdata)
{
Onion *onion = (Onion *)object;
if (length > ONION_MAX_PACKET_SIZE) {
return 1;
}
if (length <= 1 + RETURN_1) {
return 1;
}
const uint8_t packet_id = packet[1 + RETURN_1];
if (packet_id != NET_PACKET_ANNOUNCE_RESPONSE && packet_id != NET_PACKET_ANNOUNCE_RESPONSE_OLD &&
packet_id != NET_PACKET_ONION_DATA_RESPONSE) {
return 1;
}
change_symmetric_key(onion);
uint8_t plain[SIZE_IPPORT];
const int len = decrypt_data_symmetric(onion->secret_symmetric_key, packet + 1, packet + 1 + CRYPTO_NONCE_SIZE,
SIZE_IPPORT + CRYPTO_MAC_SIZE, plain);
if ((uint32_t)len != SIZE_IPPORT) {
return 1;
}
IP_Port send_to;
if (ipport_unpack(&send_to, plain, len, true) == -1) {
LOGGER_DEBUG(onion->log, "failed to unpack IP/Port");
return 1;
}
const uint16_t data_len = length - (1 + RETURN_1);
if (onion->recv_1_function != nullptr &&
!net_family_is_ipv4(send_to.ip.family) &&
!net_family_is_ipv6(send_to.ip.family)) {
return onion->recv_1_function(onion->callback_object, &send_to, packet + (1 + RETURN_1), data_len);
}
if ((uint32_t)sendpacket(onion->net, &send_to, packet + (1 + RETURN_1), data_len) != data_len) {
return 1;
}
return 0;
}
void set_callback_handle_recv_1(Onion *onion, onion_recv_1_cb *function, void *object)
{
onion->recv_1_function = function;
onion->callback_object = object;
}
Onion *new_onion(const Logger *log, const Memory *mem, const Mono_Time *mono_time, const Random *rng, DHT *dht)
{
if (dht == nullptr) {
return nullptr;
}
Onion *onion = (Onion *)mem_alloc(mem, sizeof(Onion));
if (onion == nullptr) {
return nullptr;
}
onion->log = log;
onion->dht = dht;
onion->net = dht_get_net(dht);
onion->mono_time = mono_time;
onion->rng = rng;
onion->mem = mem;
new_symmetric_key(rng, onion->secret_symmetric_key);
onion->timestamp = mono_time_get(onion->mono_time);
const uint8_t *secret_key = dht_get_self_secret_key(dht);
onion->shared_keys_1 = shared_key_cache_new(log, mono_time, mem, secret_key, KEYS_TIMEOUT, MAX_KEYS_PER_SLOT);
onion->shared_keys_2 = shared_key_cache_new(log, mono_time, mem, secret_key, KEYS_TIMEOUT, MAX_KEYS_PER_SLOT);
onion->shared_keys_3 = shared_key_cache_new(log, mono_time, mem, secret_key, KEYS_TIMEOUT, MAX_KEYS_PER_SLOT);
if (onion->shared_keys_1 == nullptr ||
onion->shared_keys_2 == nullptr ||
onion->shared_keys_3 == nullptr) {
// cppcheck-suppress mismatchAllocDealloc
kill_onion(onion);
return nullptr;
}
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_INITIAL, &handle_send_initial, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_1, &handle_send_1, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_2, &handle_send_2, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_3, &handle_recv_3, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_2, &handle_recv_2, onion);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_1, &handle_recv_1, onion);
return onion;
}
void kill_onion(Onion *onion)
{
if (onion == nullptr) {
return;
}
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_INITIAL, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_1, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_SEND_2, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_3, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_2, nullptr, nullptr);
networking_registerhandler(onion->net, NET_PACKET_ONION_RECV_1, nullptr, nullptr);
crypto_memzero(onion->secret_symmetric_key, sizeof(onion->secret_symmetric_key));
shared_key_cache_free(onion->shared_keys_1);
shared_key_cache_free(onion->shared_keys_2);
shared_key_cache_free(onion->shared_keys_3);
mem_delete(onion->mem, onion);
}