I2NPMessage * CreateDatabaseStoreMsg (const i2p::data::RouterInfo * router)
{
if (!router) // we send own RouterInfo
router = &context.GetRouterInfo ();
I2NPMessage * m = NewI2NPShortMessage ();
I2NPDatabaseStoreMsg * msg = (I2NPDatabaseStoreMsg *)m->GetPayload ();
memcpy (msg->key, router->GetIdentHash (), 32);
msg->type = 0;
msg->replyToken = 0;
CryptoPP::Gzip compressor;
compressor.Put (router->GetBuffer (), router->GetBufferLen ());
compressor.MessageEnd();
auto size = compressor.MaxRetrievable ();
uint8_t * buf = m->GetPayload () + sizeof (I2NPDatabaseStoreMsg);
*(uint16_t *)buf = htobe16 (size); // size
buf += 2;
// TODO: check if size doesn't exceed buffer
compressor.Get (buf, size);
m->len += sizeof (I2NPDatabaseStoreMsg) + 2 + size; // payload size
FillI2NPMessageHeader (m, eI2NPDatabaseStore);
return m;
}
Data Gzip::Compress(const Data &data) {
CryptoPP::Gzip zipper;
zipper.Put((byte *) data.data(), data.size());
zipper.MessageEnd();
Data compressed(zipper.MaxRetrievable());
zipper.Get((byte *) compressed.data(), compressed.size());
return compressed;
}
I2NPMessage * DatagramDestination::CreateDataMessage (const uint8_t * payload, size_t len)
{
I2NPMessage * msg = NewI2NPMessage ();
CryptoPP::Gzip compressor; // default level
compressor.Put (payload, len);
compressor.MessageEnd();
int size = compressor.MaxRetrievable ();
uint8_t * buf = msg->GetPayload ();
*(uint32_t *)buf = htobe32 (size); // length
buf += 4;
compressor.Get (buf, size);
memset (buf + 4, 0, 4); // source and destination are zeroes
buf[9] = i2p::client::PROTOCOL_TYPE_DATAGRAM; // datagram protocol
msg->len += size + 4;
FillI2NPMessageHeader (msg, eI2NPData);
return msg;
}
I2NPMessage * DatagramDestination::CreateDataMessage (const uint8_t * payload, size_t len, uint16_t fromPort, uint16_t toPort)
{
I2NPMessage * msg = NewI2NPMessage ();
CryptoPP::Gzip compressor; // default level
compressor.Put (payload, len);
compressor.MessageEnd();
int size = compressor.MaxRetrievable ();
uint8_t * buf = msg->GetPayload ();
htobe32buf (buf, size); // length
buf += 4;
compressor.Get (buf, size);
htobe16buf (buf + 4, fromPort); // source port
htobe16buf (buf + 6, toPort); // destination port
buf[9] = i2p::client::PROTOCOL_TYPE_DATAGRAM; // datagram protocol
msg->len += size + 4;
FillI2NPMessageHeader (msg, eI2NPData);
return msg;
}