static int handle_ping_response(void *object, IP_Port source, const uint8_t *packet, uint16_t length, void *userdata)
{
DHT *dht = (DHT *)object;
int rc;
if (length != DHT_PING_SIZE) {
return 1;
}
PING *ping = dht->ping;
if (id_equal(packet + 1, ping->dht->self_public_key)) {
return 1;
}
uint8_t shared_key[CRYPTO_SHARED_KEY_SIZE];
// generate key to encrypt ping_id with recipient privkey
DHT_get_shared_key_sent(ping->dht, shared_key, packet + 1);
uint8_t ping_plain[PING_PLAIN_SIZE];
// Decrypt ping_id
rc = decrypt_data_symmetric(shared_key,
packet + 1 + CRYPTO_PUBLIC_KEY_SIZE,
packet + 1 + CRYPTO_PUBLIC_KEY_SIZE + CRYPTO_NONCE_SIZE,
PING_PLAIN_SIZE + CRYPTO_MAC_SIZE,
ping_plain);
if (rc != sizeof(ping_plain)) {
return 1;
}
if (ping_plain[0] != NET_PACKET_PING_RESPONSE) {
return 1;
}
uint64_t ping_id;
memcpy(&ping_id, ping_plain + 1, sizeof(ping_id));
uint8_t data[PING_DATA_SIZE];
if (ping_array_check(data, sizeof(data), &ping->ping_array, ping_id) != sizeof(data)) {
return 1;
}
if (!id_equal(packet + 1, data)) {
return 1;
}
IP_Port ipp;
memcpy(&ipp, data + CRYPTO_PUBLIC_KEY_SIZE, sizeof(IP_Port));
if (!ipport_equal(&ipp, &source)) {
return 1;
}
addto_lists(dht, source, packet + 1);
return 0;
}
static int handle_ping_response(void *_dht, IP_Port source, const uint8_t *packet, uint16_t length)
{
DHT *dht = _dht;
int rc;
if (length != DHT_PING_SIZE)
return 1;
PING *ping = dht->ping;
if (id_equal(packet + 1, ping->dht->self_public_key))
return 1;
uint8_t shared_key[crypto_box_BEFORENMBYTES];
// generate key to encrypt ping_id with recipient privkey
DHT_get_shared_key_sent(ping->dht, shared_key, packet + 1);
uint8_t ping_plain[PING_PLAIN_SIZE];
// Decrypt ping_id
rc = decrypt_data_symmetric(shared_key,
packet + 1 + crypto_box_PUBLICKEYBYTES,
packet + 1 + crypto_box_PUBLICKEYBYTES + crypto_box_NONCEBYTES,
PING_PLAIN_SIZE + crypto_box_MACBYTES,
ping_plain);
if (rc != sizeof(ping_plain))
return 1;
if (ping_plain[0] != NET_PACKET_PING_RESPONSE)
return 1;
uint64_t ping_id;
memcpy(&ping_id, ping_plain + 1, sizeof(ping_id));
uint8_t data[PING_DATA_SIZE];
if (ping_array_check(data, sizeof(data), &ping->ping_array, ping_id) != sizeof(data))
return 1;
if (!id_equal(packet + 1, data))
return 1;
IP_Port ipp;
memcpy(&ipp, data + crypto_box_PUBLICKEYBYTES, sizeof(IP_Port));
if (!ipport_equal(&ipp, &source))
return 1;
addto_lists(dht, source, packet + 1);
return 0;
}
/* Checks if the sendback is valid and returns the public key contained in it in ret_pubkey and the
* ip contained in it in ret_ip_port
*
* sendback is the sendback ONION_ANNOUNCE_SENDBACK_DATA_LENGTH big
* ret_pubkey must be at least crypto_box_PUBLICKEYBYTES big
* ret_ip_port must be at least 1 big
*
* return ~0 on failure
* return num (see new_sendback(...)) on success
*/
static uint32_t check_sendback(Onion_Client *onion_c, const uint8_t *sendback, uint8_t *ret_pubkey,
IP_Port *ret_ip_port)
{
uint64_t sback;
memcpy(&sback, sendback, sizeof(uint64_t));
uint8_t data[sizeof(uint32_t) + crypto_box_PUBLICKEYBYTES + sizeof(IP_Port)];
if (ping_array_check(data, sizeof(data), &onion_c->announce_ping_array, sback) != sizeof(data))
return ~0;
memcpy(ret_pubkey, data + sizeof(uint32_t), crypto_box_PUBLICKEYBYTES);
memcpy(ret_ip_port, data + sizeof(uint32_t) + crypto_box_PUBLICKEYBYTES, sizeof(IP_Port));
uint32_t num;
memcpy(&num, data, sizeof(uint32_t));
return num;
}