void connection::write(const net::buffer& data)
{
if(m_service.check_this_loop()){
write_in_loop(data.data(),data.size());
}else{
m_service.run_task( boost::bind(&connection::write_in_loop,this,data.data(),data.size()) );
}
}
bool message_udp::recv::node_list::expect(const net::buffer & recv_buf)
{
if(recv_buf.size() < protocol_udp::node_list_size){
return false;
}
if(recv_buf[0] != protocol_udp::node_list){
return false;
}
if((recv_buf.size() - protocol_udp::node_list_size) % 20 != 0){
return false;
}
return std::memcmp(recv_buf.data()+1, random.data(), 4) == 0;
}
void encryption::crypt_send(net::buffer & send_buff, const int index)
{
assert(enable_crypt);
for(int x=index; x<send_buff.size(); ++x){
send_buff[x] ^= PRNG_send.byte();
}
}
void encryption::crypt_recv(net::buffer & recv_buff, const int index)
{
assert(enable_crypt);
for(int x=index; x<recv_buff.size(); ++x){
recv_buff[x] ^= PRNG_recv.byte();
}
}
bool message_udp::recv::host_list::recv(const net::buffer & recv_buf,
const net::endpoint & endpoint)
{
if(!expect(recv_buf)){
return false;
}
std::string remote_ID(convert::bin_to_hex(std::string(
reinterpret_cast<const char *>(recv_buf.data())+5, 20)));
bit_field BF(recv_buf.data()+25, 2, 16);
std::list<net::endpoint> hosts;
unsigned offset = protocol_udp::host_list_size;
for(unsigned x=0; x<16 && offset != recv_buf.size(); ++x){
if(BF[x] == 0){
//IPv4
boost::optional<net::endpoint> ep = net::bin_to_endpoint(
recv_buf.str(offset, 4), recv_buf.str(offset + 4, 2));
if(ep){
hosts.push_back(*ep);
}
offset += 6;
}else{
//IPv6
boost::optional<net::endpoint> ep = net::bin_to_endpoint(
recv_buf.str(offset, 16), recv_buf.str(offset + 16, 2));
if(ep){
hosts.push_back(*ep);
}
offset += 18;
}
}
func(endpoint, remote_ID, hosts);
return true;
}
//BEGIN send::host_list
message_udp::send::host_list::host_list(const net::buffer & random,
const std::string & local_ID,
const std::list<net::endpoint> & hosts)
{
assert(random.size() == 4);
assert(hosts.size() <= protocol_udp::host_list_elements);
bit_field BF(16);
unsigned cnt = 0;
for(std::list<net::endpoint>::const_iterator it_cur = hosts.begin(),
it_end = hosts.end(); it_cur != it_end; ++it_cur)
{
if(it_cur->version() == net::IPv4){
BF[cnt] = 0;
}else{
BF[cnt] = 1;
}
++cnt;
}
buf.append(protocol_udp::host_list)
.append(random)
.append(convert::hex_to_bin(local_ID))
.append(BF.get_buf());
//append addresses
for(std::list<net::endpoint>::const_iterator it_cur = hosts.begin(),
it_end = hosts.end(); it_cur != it_end; ++it_cur)
{
buf.append(it_cur->IP_bin())
.append(it_cur->port_bin());
}
}
//BEGIN send::store_node
message_udp::send::store_node::store_node(const net::buffer & random,
const std::string & local_ID)
{
assert(random.size() == 4);
assert(local_ID.size() == SHA1::hex_size);
buf.append(protocol_udp::store_node)
.append(random)
.append(convert::hex_to_bin(local_ID));
}
bool message_udp::recv::find_node::expect(const net::buffer & recv_buf)
{
if(recv_buf.size() != protocol_udp::find_node_size){
return false;
}
if(recv_buf[0] != protocol_udp::find_node){
return false;
}
return true;
}
bool message_udp::recv::pong::expect(const net::buffer & recv_buf)
{
if(recv_buf.size() != protocol_udp::pong_size){
return false;
}
if(recv_buf[0] != protocol_udp::pong){
return false;
}
return std::memcmp(recv_buf.data()+1, random.data(), 4) == 0;
}
//BEGIN send::query_file
message_udp::send::query_file::query_file(const net::buffer & random,
const std::string & local_ID, const std::string & hash)
{
assert(random.size() == 4);
assert(local_ID.size() == SHA1::hex_size);
assert(hash.size() == SHA1::hex_size);
buf.append(protocol_udp::query_file)
.append(random)
.append(convert::hex_to_bin(local_ID))
.append(convert::hex_to_bin(hash));
}
void encryption::recv_rB(const net::buffer & buf)
{
assert(enable_recv_rB);
set_enable_false();
enable_crypt = true;
assert(buf.size() == protocol_tcp::DH_key_size);
remote_result = mpa::mpint(buf.data(), protocol_tcp::DH_key_size);
shared_key = mpa::exptmod(remote_result, s, p);
std::string bin = shared_key.bin(protocol_tcp::DH_key_size);
PRNG_send.seed(reinterpret_cast<const unsigned char *>(bin.data()), bin.size());
PRNG_recv.seed(reinterpret_cast<const unsigned char *>(bin.data()), bin.size());
}
//BEGIN send::node_list
message_udp::send::node_list::node_list(const net::buffer & random,
const std::string & local_ID, const std::list<std::string> & nodes)
{
assert(random.size() == 4);
assert(local_ID.size() == SHA1::hex_size);
assert(nodes.size() <= protocol_udp::node_list_elements);
buf.append(protocol_udp::node_list)
.append(random)
.append(convert::hex_to_bin(local_ID));
for(std::list<std::string>::const_iterator it_cur = nodes.begin(),
it_end = nodes.end(); it_cur != it_end; ++it_cur)
{
assert(it_cur->size() == SHA1::hex_size);
buf.append(convert::hex_to_bin(*it_cur));
}
}
bool message_udp::recv::node_list::recv(const net::buffer & recv_buf,
const net::endpoint & endpoint)
{
if(!expect(recv_buf)){
return false;
}
net::buffer random(recv_buf.data()+1, 4);
std::string remote_ID(convert::bin_to_hex(std::string(
reinterpret_cast<const char *>(recv_buf.data())+5, 20)));
std::list<std::string> nodes;
unsigned offset = protocol_udp::node_list_size;
for(unsigned x=0; x<16 && offset != recv_buf.size(); ++x){
nodes.push_back(convert::bin_to_hex(std::string(
reinterpret_cast<const char *>(recv_buf.data())+offset, 20)));
offset += 20;
}
func(endpoint, random, remote_ID, nodes);
return true;
}
bool encryption::recv_p_rA(const net::buffer & buf)
{
assert(enable_recv_p_rA);
set_enable_false();
enable_send_rB = true;
assert(buf.size() == protocol_tcp::DH_key_size * 2);
p = mpa::mpint(buf.data(), protocol_tcp::DH_key_size);
if(!mpa::is_prime(p)){
return false;
}
remote_result = mpa::mpint(buf.data() + protocol_tcp::DH_key_size, protocol_tcp::DH_key_size);
local_result = mpa::exptmod(g, s, p);
shared_key = mpa::exptmod(remote_result, s, p);
std::string bin = shared_key.bin(protocol_tcp::DH_key_size);
PRNG_send.seed(reinterpret_cast<const unsigned char *>(bin.data()), bin.size());
PRNG_recv.seed(reinterpret_cast<const unsigned char *>(bin.data()), bin.size());
return true;
}
bool message_udp::recv::host_list::expect(const net::buffer & recv_buf)
{
//check minimum size
if(recv_buf.size() < protocol_udp::host_list_size || recv_buf.size() > 508){
return false;
}
//check command
if(recv_buf[0] != protocol_udp::host_list){
return false;
}
//check random
if(std::memcmp(recv_buf.data()+1, random.data(), 4) != 0){
return false;
}
//verify address list makes sense
bit_field BF(recv_buf.data()+25, 2, 16);
unsigned offset = protocol_udp::host_list_size;
for(unsigned x=0; x<16 && offset != recv_buf.size(); ++x){
if(BF[x] == 0){
//IPv4
if(recv_buf.size() < offset + 6){
return false;
}
offset += 6;
}else{
//IPv6
if(recv_buf.size() < offset + 18){
return false;
}
offset += 18;
}
}
//check if longer than expected
if(offset != recv_buf.size()){
return false;
}
return true;
}
bool message_udp::recv::ping::expect(const net::buffer & recv_buf)
{
return recv_buf.size() == protocol_udp::ping_size
&& recv_buf[0] == protocol_udp::ping;
}