fixed race condition between local buffer creation and sending it through the transports

This commit is contained in:
orignal 2024-05-26 15:33:37 -04:00
parent 7dc5a04b8d
commit acbd3f897b
8 changed files with 51 additions and 18 deletions

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@ -129,7 +129,8 @@ namespace transport
options[1] = 2; // ver
htobe16buf (options + 2, paddingLength); // padLen
// m3p2Len
auto bufLen = i2p::context.GetRouterInfo ().GetBufferLen ();
auto riBuffer = i2p::context.CopyRouterInfoBuffer ();
auto bufLen = riBuffer->GetBufferLen ();
m3p2Len = bufLen + 4 + 16; // (RI header + RI + MAC for now) TODO: implement options
htobe16buf (options + 4, m3p2Len);
// fill m3p2 payload (RouterInfo block)
@ -138,7 +139,7 @@ namespace transport
m3p2[0] = eNTCP2BlkRouterInfo; // block
htobe16buf (m3p2 + 1, bufLen + 1); // flag + RI
m3p2[3] = 0; // flag
memcpy (m3p2 + 4, i2p::context.GetRouterInfo ().GetBuffer (), bufLen); // TODO: own RI should be protected by mutex
memcpy (m3p2 + 4, riBuffer->data (), bufLen); // TODO: eliminate extra copy
// 2 bytes reserved
htobe32buf (options + 8, (i2p::util::GetMillisecondsSinceEpoch () + 500)/1000); // tsA, rounded to seconds
// 4 bytes reserved
@ -1200,7 +1201,8 @@ namespace transport
void NTCP2Session::SendRouterInfo ()
{
if (!IsEstablished ()) return;
auto riLen = i2p::context.GetRouterInfo ().GetBufferLen ();
auto riBuffer = i2p::context.CopyRouterInfoBuffer ();
auto riLen = riBuffer->GetBufferLen ();
size_t payloadLen = riLen + 3 + 1 + 7; // 3 bytes block header + 1 byte RI flag + 7 bytes DateTime
m_NextSendBuffer = new uint8_t[payloadLen + 16 + 2 + 64]; // up to 64 bytes padding
// DateTime block
@ -1211,7 +1213,7 @@ namespace transport
m_NextSendBuffer[9] = eNTCP2BlkRouterInfo;
htobe16buf (m_NextSendBuffer + 10, riLen + 1); // size
m_NextSendBuffer[12] = 0; // flag
memcpy (m_NextSendBuffer + 13, i2p::context.GetRouterInfo ().GetBuffer (), riLen);
memcpy (m_NextSendBuffer + 13, riBuffer->data (), riLen); // TODO: eliminate extra copy
// padding block
auto paddingSize = CreatePaddingBlock (payloadLen, m_NextSendBuffer + 2 + payloadLen, 64);
payloadLen += paddingSize;

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@ -119,7 +119,11 @@ namespace data
size_t VisitRandomRouterInfos(RouterInfoFilter f, RouterInfoVisitor v, size_t n);
void ClearRouterInfos () { m_RouterInfos.clear (); };
std::shared_ptr<RouterInfo::Buffer> NewRouterInfoBuffer () { return m_RouterInfoBuffersPool.AcquireSharedMt (); };
template<typename... TArgs>
std::shared_ptr<RouterInfo::Buffer> NewRouterInfoBuffer (TArgs&&... args)
{
return m_RouterInfoBuffersPool.AcquireSharedMt (std::forward<TArgs>(args)...);
}
bool PopulateRouterInfoBuffer (std::shared_ptr<RouterInfo> r);
std::shared_ptr<RouterInfo::Address> NewRouterInfoAddress () { return m_RouterInfoAddressesPool.AcquireSharedMt (); };
boost::shared_ptr<RouterInfo::Addresses> NewRouterInfoAddresses ()

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@ -78,6 +78,12 @@ namespace i2p
}
}
std::shared_ptr<i2p::data::RouterInfo::Buffer> RouterContext::CopyRouterInfoBuffer () const
{
std::lock_guard<std::mutex> l(m_RouterInfoMutex);
return m_RouterInfo.CopyBuffer ();
}
void RouterContext::CreateNewRouter ()
{
m_Keys = i2p::data::PrivateKeys::CreateRandomKeys (i2p::data::SIGNING_KEY_TYPE_EDDSA_SHA512_ED25519,
@ -246,7 +252,10 @@ namespace i2p
void RouterContext::UpdateRouterInfo ()
{
{
std::lock_guard<std::mutex> l(m_RouterInfoMutex);
m_RouterInfo.CreateBuffer (m_Keys);
}
m_RouterInfo.SaveToFile (i2p::fs::DataDirPath (ROUTER_INFO));
m_LastUpdateTime = i2p::util::GetSecondsSinceEpoch ();
}

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@ -114,6 +114,7 @@ namespace garlic
return std::shared_ptr<i2p::garlic::GarlicDestination> (this,
[](i2p::garlic::GarlicDestination *) {});
}
std::shared_ptr<i2p::data::RouterInfo::Buffer> CopyRouterInfoBuffer () const;
const uint8_t * GetNTCP2StaticPublicKey () const { return m_NTCP2Keys ? m_NTCP2Keys->staticPublicKey : nullptr; };
const uint8_t * GetNTCP2StaticPrivateKey () const { return m_NTCP2Keys ? m_NTCP2Keys->staticPrivateKey : nullptr; };
@ -258,6 +259,7 @@ namespace garlic
std::unordered_set<i2p::data::IdentHash> m_PublishExcluded;
uint32_t m_PublishReplyToken;
bool m_IsHiddenMode; // not publish
mutable std::mutex m_RouterInfoMutex;
};
extern RouterContext context;

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@ -1120,6 +1120,12 @@ namespace data
m_Buffer->SetBufferLen (len);
}
std::shared_ptr<RouterInfo::Buffer> RouterInfo::CopyBuffer () const
{
if (!m_Buffer) return nullptr;
return netdb.NewRouterInfoBuffer (*m_Buffer);
}
std::shared_ptr<RouterInfo::Buffer> RouterInfo::NewBuffer () const
{
return netdb.NewRouterInfoBuffer ();

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@ -188,6 +188,7 @@ namespace data
Buffer () = default;
Buffer (const uint8_t * buf, size_t len);
Buffer (const Buffer& other): Buffer (other.data (), other.m_BufferLen) {};
size_t GetBufferLen () const { return m_BufferLen; };
void SetBufferLen (size_t len) { m_BufferLen = len; };
@ -282,6 +283,7 @@ namespace data
size_t GetBufferLen () const { return m_Buffer ? m_Buffer->GetBufferLen () : 0; };
void DeleteBuffer () { m_Buffer = nullptr; };
std::shared_ptr<Buffer> GetSharedBuffer () const { return m_Buffer; };
std::shared_ptr<Buffer> CopyBuffer () const;
bool IsUpdated () const { return m_IsUpdated; };
void SetUpdated (bool updated) { m_IsUpdated = updated; };

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@ -337,7 +337,7 @@ namespace transport
{
if (!s->IsEstablished ()) return;
uint8_t payload[SSU2_MAX_PACKET_SIZE];
size_t payloadSize = s->CreateRouterInfoBlock (payload, s->m_MaxPayloadSize - 32, i2p::context.GetSharedRouterInfo ());
size_t payloadSize = s->CreateRouterInfoBlock (payload, s->m_MaxPayloadSize - 32, i2p::context.CopyRouterInfoBuffer ());
if (payloadSize)
{
if (payloadSize < s->m_MaxPayloadSize)
@ -883,12 +883,12 @@ namespace transport
// payload
size_t maxPayloadSize = m_MaxPayloadSize - 48; // for part 2, 48 is part1
uint8_t * payload = m_SentHandshakePacket->payload;
size_t payloadSize = CreateRouterInfoBlock (payload, maxPayloadSize, i2p::context.GetSharedRouterInfo ());
size_t payloadSize = CreateRouterInfoBlock (payload, maxPayloadSize, i2p::context.CopyRouterInfoBuffer ());
if (!payloadSize)
{
// split by two fragments
maxPayloadSize += m_MaxPayloadSize;
payloadSize = CreateRouterInfoBlock (payload, maxPayloadSize, i2p::context.GetSharedRouterInfo ());
payloadSize = CreateRouterInfoBlock (payload, maxPayloadSize, i2p::context.CopyRouterInfoBuffer ());
header.h.flags[0] = 0x02; // frag 0, total fragments 2
// TODO: check if we need more fragments
}
@ -2537,19 +2537,25 @@ namespace transport
size_t SSU2Session::CreateRouterInfoBlock (uint8_t * buf, size_t len, std::shared_ptr<const i2p::data::RouterInfo> r)
{
if (!r || !r->GetBuffer () || len < 5) return 0;
if (!r || len < 5) return 0;
return CreateRouterInfoBlock (buf, len, r->GetSharedBuffer ());
}
size_t SSU2Session::CreateRouterInfoBlock (uint8_t * buf, size_t len, std::shared_ptr<const i2p::data::RouterInfo::Buffer> riBuffer)
{
if (!riBuffer || len < 5) return 0;
buf[0] = eSSU2BlkRouterInfo;
size_t size = r->GetBufferLen ();
size_t size = riBuffer->GetBufferLen ();
if (size + 5 < len)
{
memcpy (buf + 5, r->GetBuffer (), size);
memcpy (buf + 5, riBuffer->data (), size);
buf[3] = 0; // flag
}
else
{
i2p::data::GzipDeflator deflator;
deflator.SetCompressionLevel (9);
size = deflator.Deflate (r->GetBuffer (), r->GetBufferLen (), buf + 5, len - 5);
size = deflator.Deflate (riBuffer->data (), riBuffer->GetBufferLen (), buf + 5, len - 5);
if (!size) return 0; // doesn't fit
buf[3] = SSU2_ROUTER_INFO_FLAG_GZIP; // flag
}
@ -2558,6 +2564,7 @@ namespace transport
return size + 5;
}
size_t SSU2Session::CreateAckBlock (uint8_t * buf, size_t len)
{
if (len < 8) return 0;

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@ -326,6 +326,7 @@ namespace transport
size_t CreateAddressBlock (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& ep);
size_t CreateRouterInfoBlock (uint8_t * buf, size_t len, std::shared_ptr<const i2p::data::RouterInfo> r);
size_t CreateRouterInfoBlock (uint8_t * buf, size_t len, std::shared_ptr<const i2p::data::RouterInfo::Buffer> riBuffer);
size_t CreateAckBlock (uint8_t * buf, size_t len);
size_t CreatePaddingBlock (uint8_t * buf, size_t len, size_t minSize = 0);
size_t CreateI2NPBlock (uint8_t * buf, size_t len, std::shared_ptr<I2NPMessage>&& msg);