size_t GarlicRoutingSession::CreateAESBlock (uint8_t * buf, std::shared_ptr<const I2NPMessage> msg)
{
size_t blockSize = 0;
bool createNewTags = m_Owner && m_NumTags && ((int)m_SessionTags.size () <= m_NumTags*2/3);
UnconfirmedTags * newTags = createNewTags ? GenerateSessionTags () : nullptr;
htobuf16 (buf, newTags ? htobe16 (newTags->numTags) : 0); // tag count
blockSize += 2;
if (newTags) // session tags recreated
{
for (int i = 0; i < newTags->numTags; i++)
{
memcpy (buf + blockSize, newTags->sessionTags[i], 32); // tags
blockSize += 32;
}
}
uint32_t * payloadSize = (uint32_t *)(buf + blockSize);
blockSize += 4;
uint8_t * payloadHash = buf + blockSize;
blockSize += 32;
buf[blockSize] = 0; // flag
blockSize++;
size_t len = CreateGarlicPayload (buf + blockSize, msg, newTags);
htobe32buf (payloadSize, len);
SHA256(buf + blockSize, len, payloadHash);
blockSize += len;
size_t rem = blockSize % 16;
if (rem)
blockSize += (16-rem); //padding
m_Encryption.Encrypt(buf, blockSize, buf);
return blockSize;
}
std::shared_ptr<I2NPMessage> CreateRouterInfoDatabaseLookupMsg (const uint8_t * key, const uint8_t * from,
uint32_t replyTunnelID, bool exploratory, std::set<i2p::data::IdentHash> * excludedPeers)
{
auto m = excludedPeers ? NewI2NPMessage () : NewI2NPShortMessage ();
uint8_t * buf = m->GetPayload ();
memcpy (buf, key, 32); // key
buf += 32;
memcpy (buf, from, 32); // from
buf += 32;
uint8_t flag = exploratory ? DATABASE_LOOKUP_TYPE_EXPLORATORY_LOOKUP : DATABASE_LOOKUP_TYPE_ROUTERINFO_LOOKUP;
if (replyTunnelID)
{
*buf = flag | DATABASE_LOOKUP_DELIVERY_FLAG; // set delivery flag
htobe32buf (buf+1, replyTunnelID);
buf += 5;
}
else
{
*buf = flag; // flag
buf++;
}
if (excludedPeers)
{
int cnt = excludedPeers->size ();
htobe16buf (buf, cnt);
buf += 2;
for (auto& it: *excludedPeers)
{
memcpy (buf, it, 32);
buf += 32;
}
}
else
{
// nothing to exclude
htobuf16 (buf, 0);
buf += 2;
}
m->len += (buf - m->GetPayload ());
m->FillI2NPMessageHeader (eI2NPDatabaseLookup);
return m;
}
