onion routing downstream traffic relaying works on testnet

CMakeLists.txt

@@ -124,7 +124,6 @@ set(LIB_SRC
   llarp/nodedb.cpp
   llarp/path.cpp
   llarp/pathbuilder.cpp
-  llarp/path_confirm.cpp
   llarp/proofofwork.cpp
   llarp/relay_ack.cpp
   llarp/relay_commit.cpp
@@ -136,6 +135,8 @@ set(LIB_SRC
   llarp/testnet.c
   llarp/time.cpp
   llarp/timer.cpp
+  llarp/routing/message_parser.cpp
+  llarp/routing/path_confirm.cpp
   vendor/cppbackport-master/lib/fs/rename.cpp
   vendor/cppbackport-master/lib/fs/filestatus.cpp
   vendor/cppbackport-master/lib/fs/filetype.cpp

Makefile

@@ -66,7 +66,7 @@ testnet-build: testnet-configure
 
 testnet: testnet-build
 	mkdir -p $(TESTNET_ROOT)
-	python3 contrib/testnet/genconf.py --bin=$(REPO)/llarpd --svc=30 --clients=300 --dir=$(TESTNET_ROOT) --out $(TESTNET_CONF)
+	python3 contrib/testnet/genconf.py --bin=$(REPO)/llarpd --svc=30 --clients=1 --dir=$(TESTNET_ROOT) --out $(TESTNET_CONF)
 	supervisord -n -d $(TESTNET_ROOT) -l $(TESTNET_LOG) -c $(TESTNET_CONF)
 
 test: debug-configure

include/llarp/bencode.hpp

@@ -48,6 +48,23 @@ namespace llarp
     return true;
   }
 
+  template < typename Int_t >
+  bool
+  BEncodeMaybeReadDictInt(const char* k, Int_t& i, bool& read,
+                          llarp_buffer_t key, llarp_buffer_t* buf)
+  {
+    if(llarp_buffer_eq(key, k))
+    {
+      if(!bencode_read_integer(buf, &i))
+      {
+        llarp::Warn("failed to decode key ", k);
+        return false;
+      }
+      read = true;
+    }
+    return true;
+  }
+
   template < typename Item_t >
   bool
   BEncodeMaybeReadVersion(const char* k, Item_t& item, uint64_t expect,

include/llarp/crypto.h

@@ -46,7 +46,7 @@ typedef byte_t llarp_tunnel_nonce_t[TUNNONCESIZE];
 /// PKE(result, publickey, secretkey, nonce)
 typedef bool (*llarp_path_dh_func)(byte_t *, byte_t *, byte_t *, byte_t *);
 
-/// TKE(result publickey, secretkey, nonce)
+/// TKE(result, publickey, secretkey, nonce)
 typedef bool (*llarp_transport_dh_func)(byte_t *, byte_t *, byte_t *, byte_t *);
 
 /// SD/SE(buffer, key, nonce)

include/llarp/messages/path_confirm.hpp

@@ -1,7 +1,7 @@
 #ifndef LLARP_MESSAGE_PATH_CONFIRM_HPP
 #define LLARP_MESSAGE_PATH_CONFIRM_HPP
 
-#include <llarp/routing_message.hpp>
+#include <llarp/routing/message.hpp>
 
 namespace llarp
 {
@@ -11,18 +11,21 @@ namespace llarp
     {
       uint64_t pathLifetime;
       uint64_t pathCreated;
-
+      PathConfirmMessage();
       PathConfirmMessage(uint64_t lifetime);
       ~PathConfirmMessage(){};
 
       bool
       BEncode(llarp_buffer_t* buf) const;
 
+      bool
+      DecodeKey(llarp_buffer_t key, llarp_buffer_t* val);
+
       bool
       BDecode(llarp_buffer_t* buf);
 
       bool
-      HandleMessage(llarp_router* r) const;
+      HandleMessage(IMessageHandler* h) const;
     };
   }  // namespace routing
 }  // namespace llarp

include/llarp/path.hpp

@@ -10,7 +10,8 @@
 #include <llarp/messages/relay_commit.hpp>
 #include <llarp/path_types.hpp>
 #include <llarp/router_id.hpp>
-#include <llarp/routing_message.hpp>
+#include <llarp/routing/handler.hpp>
+#include <llarp/routing/message.hpp>
 
 #include <list>
 #include <map>
@@ -173,7 +174,7 @@ namespace llarp
   };
 
   /// A path we made
-  struct Path : public IHopHandler
+  struct Path : public IHopHandler, public llarp::routing::IMessageHandler
   {
     typedef std::vector< PathHopConfig > HopList;
     HopList hops;
@@ -207,6 +208,9 @@ namespace llarp
 
     RouterID
     Upstream() const;
+
+   protected:
+    llarp::routing::InboundMessageParser m_InboundMessageParser;
   };
 
   enum PathBuildStatus

include/llarp/routing/handler.hpp

@@ -0,0 +1,14 @@
+#ifndef LLARP_ROUTING_HANDLER_HPP
+#define LLARP_ROUTING_HANDLER_HPP
+
+namespace llarp
+{
+  namespace routing
+  {
+    struct IMessageHandler
+    {
+    };
+  }  // namespace routing
+}  // namespace llarp
+
+#endif

include/llarp/routing/message.hpp

@@ -0,0 +1,46 @@
+#ifndef LLARP_ROUTING_MESSAGE_HPP
+#define LLARP_ROUTING_MESSAGE_HPP
+
+#include <llarp/buffer.h>
+#include <llarp/router.h>
+#include <llarp/path_types.hpp>
+
+namespace llarp
+{
+  namespace routing
+  {
+    struct IMessageHandler;
+
+    struct IMessage
+    {
+      llarp::PathID_t from;
+
+      virtual ~IMessage(){};
+
+      virtual bool
+      BEncode(llarp_buffer_t* buf) const = 0;
+
+      virtual bool
+      DecodeKey(llarp_buffer_t key, llarp_buffer_t* buf) = 0;
+
+      virtual bool
+      HandleMessage(IMessageHandler* r) const = 0;
+    };
+
+    struct InboundMessageParser
+    {
+      InboundMessageParser();
+      bool
+      ParseMessageBuffer(llarp_buffer_t buf, IMessageHandler* handler);
+
+     private:
+      static bool
+      OnKey(dict_reader* r, llarp_buffer_t* key);
+      bool firstKey;
+      dict_reader reader;
+      IMessage* msg;
+    };
+  }  // namespace routing
+}  // namespace llarp
+
+#endif

include/llarp/routing_message.hpp

@@ -1,30 +0,0 @@
-#ifndef LLARP_ROUTING_MESSAGE_HPP
-#define LLARP_ROUTING_MESSAGE_HPP
-
-#include <llarp/buffer.h>
-#include <llarp/router.h>
-#include <llarp/path_types.hpp>
-
-namespace llarp
-{
-  namespace routing
-  {
-    struct IMessage
-    {
-      llarp::PathID_t from;
-
-      virtual ~IMessage(){};
-
-      virtual bool
-      BEncode(llarp_buffer_t* buf) const = 0;
-
-      virtual bool
-      BDecode(llarp_buffer_t* buf) = 0;
-
-      virtual bool
-      HandleMessage(llarp_router* r) const = 0;
-    };
-  }  // namespace routing
-}  // namespace llarp
-
-#endif

llarp/iwp_link.cpp

@@ -1397,7 +1397,7 @@ namespace iwp
         UnmapAddr(addr);
         session *s = static_cast< session * >(itr->second.impl);
         s->done();
-        m_sessions.erase(itr);
+        m_sessions.erase(addr);
         if(s->frames)
         {
           llarp::Warn("session has ", s->frames,

llarp/nodedb.cpp

@@ -291,7 +291,8 @@ nodedb_async_load_rc(void *user)
   llarp_logic_queue_job(job->logic, {job, &nodedb_inform_load_rc});
 }
 
-extern "C" {
+extern "C"
+{
   struct llarp_nodedb *
   llarp_nodedb_new(struct llarp_crypto *crypto)
   {
@@ -393,7 +394,7 @@ llarp_nodedb_select_random_hop(struct llarp_nodedb *n, struct llarp_rc *prev,
         auto itr = n->entries.begin();
         if(sz > 1)
         {
-        auto idx = rand() % (sz - 1);
+          auto idx = rand() % sz;
           std::advance(itr, idx);
         }
         if(memcmp(prev->pubkey, itr->second.pubkey, PUBKEYSIZE) == 0)
@@ -407,7 +408,7 @@ llarp_nodedb_select_random_hop(struct llarp_nodedb *n, struct llarp_rc *prev,
       auto itr = n->entries.begin();
       if(sz > 1)
       {
-      auto idx = rand() % (sz - 1);
+        auto idx = rand() % sz;
         std::advance(itr, idx);
       }
       llarp_rc_copy(result, &itr->second);

llarp/path.cpp

@@ -269,14 +269,9 @@ namespace llarp
   Path::HandleDownstream(llarp_buffer_t buf, const TunnelNonce& Y,
                          llarp_router* r)
   {
-    size_t idx = hops.size() - 1;
-    while(idx >= 0)
+    for(const auto& hop : hops)
     {
-      r->crypto.xchacha20(buf, hops[idx].shared, Y);
-      if(idx)
-        idx--;
-      else
-        break;
+      r->crypto.xchacha20(buf, hop.shared, Y);
     }
     return HandleRoutingMessage(buf, r);
   }
@@ -284,7 +279,11 @@ namespace llarp
   bool
   Path::HandleRoutingMessage(llarp_buffer_t buf, llarp_router* r)
   {
-    // TODO: implement me
+    if(!m_InboundMessageParser.ParseMessageBuffer(buf, this))
+    {
+      llarp::Warn("Failed to parse inbound routing message");
+      return false;
+    }
     return true;
   }
 

llarp/pathbuilder.cpp

@@ -47,10 +47,9 @@ namespace llarp
         abort();
         return;
       }
-
       ++ctx->idx;
 
-      bool isFarthestHop = ctx->idx == ctx->path->hops.size() - 1;
+      bool isFarthestHop = ctx->idx == ctx->path->hops.size();
 
       if(isFarthestHop)
       {

llarp/routing/message_parser.cpp

@@ -0,0 +1,69 @@
+#include <llarp/messages/path_confirm.hpp>
+#include <llarp/routing/message.hpp>
+
+namespace llarp
+{
+  namespace routing
+  {
+    InboundMessageParser::InboundMessageParser()
+    {
+      reader.user   = this;
+      reader.on_key = &OnKey;
+      firstKey      = false;
+    }
+
+    bool
+    InboundMessageParser::OnKey(dict_reader* r, llarp_buffer_t* key)
+    {
+      InboundMessageParser* self =
+          static_cast< InboundMessageParser* >(r->user);
+
+      if(key == nullptr && self->firstKey)
+      {
+        // empty dict
+        return false;
+      }
+      if(!key)
+        return true;
+      if(self->firstKey)
+      {
+        llarp_buffer_t strbuf;
+        if(!llarp_buffer_eq(*key, "A"))
+          return false;
+        if(!bencode_read_string(r->buffer, &strbuf))
+          return false;
+        if(strbuf.sz != 1)
+          return false;
+        switch(*strbuf.cur)
+        {
+          case 'P':
+            self->msg = new PathConfirmMessage;
+            break;
+          default:
+            llarp::Error("invalid routing message id: ", *strbuf.cur);
+        }
+        self->firstKey = false;
+        return self->msg != nullptr;
+      }
+      else
+      {
+        return self->msg->DecodeKey(*key, r->buffer);
+      }
+    }
+
+    bool
+    InboundMessageParser::ParseMessageBuffer(llarp_buffer_t buf,
+                                             IMessageHandler* h)
+    {
+      bool result = false;
+      msg         = nullptr;
+      firstKey    = true;
+      if(bencode_read_dict(&buf, &reader))
+      {
+        result = msg->HandleMessage(h);
+        delete msg;
+      }
+      return result;
+    }
+  }  // namespace routing
+}  // namespace llarp

llarp/routing/path_confirm.cpp

@@ -1,16 +1,32 @@
 #include <llarp/time.h>
 #include <llarp/bencode.hpp>
 #include <llarp/messages/path_confirm.hpp>
+#include <llarp/routing/handler.hpp>
 
 namespace llarp
 {
   namespace routing
   {
+    PathConfirmMessage::PathConfirmMessage() : pathLifetime(0), pathCreated(0)
+    {
+    }
+
     PathConfirmMessage::PathConfirmMessage(uint64_t lifetime)
         : pathLifetime(lifetime), pathCreated(llarp_time_now_ms())
     {
     }
 
+    bool
+    PathConfirmMessage::DecodeKey(llarp_buffer_t key, llarp_buffer_t* val)
+    {
+      bool read = false;
+      if(!BEncodeMaybeReadDictInt("L", pathLifetime, read, key, val))
+        return false;
+      if(!BEncodeMaybeReadDictInt("S", pathCreated, read, key, val))
+        return false;
+      return read;
+    }
+
     bool
     PathConfirmMessage::BEncode(llarp_buffer_t* buf) const
     {
@@ -26,14 +42,10 @@ namespace llarp
     }
 
     bool
-    PathConfirmMessage::BDecode(llarp_buffer_t* buf)
-    {
-      return false;
-    }
-
-    bool
-    PathConfirmMessage::HandleMessage(llarp_router* r) const
+    PathConfirmMessage::HandleMessage(IMessageHandler* h) const
     {
+      llarp::Info("got path confirm created=", pathCreated,
+                  " lifetime=", pathLifetime);
       return true;
     }