hidden service tags

CMakeLists.txt

@@ -242,6 +242,7 @@ set(LIB_SRC
   llarp/service/address.cpp
   llarp/service/context.cpp
   llarp/service/endpoint.cpp
+  llarp/service/tag.cpp
   llarp/service/info.cpp
   ${LIBTUNTAP_SRC}
 )

doc/dht_v0.txt

@@ -21,22 +21,32 @@ variant 2: recursively find many IS in a tag
 
 {
   A: "F",
+  E: "<N*32 bytes optional exclude SA list>",
   I: 0 or 1 if iterative request,
   N: "<16 bytes topic tag>",
   T: transaction_id_uint64,
   V: 0
 }
 
+exclude adding service addresses in E if present
+
+
 got introduction message (GIM)
 
+sent in reply to FIM and PIM
+
 {
   A: "G",
-  I: [IS],
+  I: [IS, IS, IS, ...],
   T: transaction_id_uint64,
   V: 0,
 }
 
 
+The I value MUST NOT contain more than 8 IS.
+The I value is either 1 or 0 IS long for PIM and FIM variant 1.
+
+
 publish introduction message (PIM)
 
 publish one IS to the DHT.

doc/proto_v0.txt

@@ -178,7 +178,7 @@ a signed set of introductions for a hidden service
 a is the service info
 i is the list of introductions that this service is advertising with
 n is a 16 byte null padded utf-8 encoded string tagging the hidden service in 
-  a topic searchable via a lookup
+  a topic searchable via a lookup (optional)
 v is the protocol version
 w is an optinal proof of work for DoS protection (slot for future)
 z is the signature of the entire IS where z is set to zero signed by the hidden
@@ -187,7 +187,7 @@ service's signing key.
 {
   a: SI,
   i: [ I, I, I, ... ],
-  n: "<16 bytes service topic>", 
+  n: "<16 bytes service topic (optional)>", 
   v: 0,
   w: optional proof of work,
   z: "<64 bytes signature using service info signing key>"

include/llarp/dht/messages/findintro.hpp

@@ -2,6 +2,7 @@
 #define LLARP_DHT_MESSAGES_FIND_INTRO_HPP
 #include <llarp/dht/message.hpp>
 #include <llarp/service/address.hpp>
+#include <llarp/service/tag.hpp>
 
 namespace llarp
 {
@@ -12,6 +13,7 @@ namespace llarp
       uint64_t R     = 0;
       bool iterative = false;
       llarp::service::Address S;
+      llarp::service::Tag N;
       uint64_t T = 0;
 
       FindIntroMessage(const Key_t& from) : IMessage(from)

include/llarp/service/IntroSet.hpp

@@ -6,6 +6,7 @@
 #include <llarp/pow.hpp>
 #include <llarp/service/Info.hpp>
 #include <llarp/service/Intro.hpp>
+#include <llarp/service/tag.hpp>
 
 #include <list>
 
@@ -19,6 +20,7 @@ namespace llarp
     {
       ServiceInfo A;
       std::list< Introduction > I;
+      Tag topic;
       llarp::PoW* W = nullptr;
       llarp::Signature Z;
 
@@ -45,7 +47,13 @@ namespace llarp
         {
           out << intro << ",";
         }
-        return out << "] V=" << i.version << " Z=" << i.Z;
+        out << "]";
+        auto topic = i.topic.ToString();
+        if(topic.size())
+        {
+          out << " topic=" << topic;
+        }
+        return out << " V=" << i.version << " Z=" << i.Z;
       }
 
       bool

include/llarp/service/tag.hpp

@@ -0,0 +1,32 @@
+#ifndef LLARP_SERVICE_TAG_HPP
+#define LLARP_SERVICE_TAG_HPP
+
+#include <llarp/aligned.hpp>
+
+namespace llarp
+{
+  namespace service
+  {
+    struct Tag : public llarp::AlignedBuffer< 16 >
+    {
+      Tag() : llarp::AlignedBuffer< 16 >()
+      {
+        Zero();
+      }
+
+      Tag(const byte_t* d) : llarp::AlignedBuffer< 16 >(d)
+      {
+      }
+
+      Tag(const std::string& str) : Tag()
+      {
+        memcpy(data(), str.c_str(), std::min(16UL, str.size()));
+      }
+
+      std::string
+      ToString() const;
+    };
+  }  // namespace service
+}  // namespace llarp
+
+#endif

llarp/service.cpp

@@ -25,6 +25,9 @@ namespace llarp
         return BEncodeReadList(I, buf);
       }
 
+      if(!BEncodeMaybeReadDictEntry("n", topic, read, key, buf))
+        return false;
+
       if(!BEncodeMaybeReadDictInt("v", version, read, key, buf))
         return false;
 
@@ -48,6 +51,12 @@ namespace llarp
         return false;
       // end introduction list
 
+      // topic tag
+      if(topic.ToString().size())
+      {
+        if(!BEncodeWriteDictEntry("n", topic, buf))
+          return false;
+      }
       // write version
       if(!BEncodeWriteDictInt(buf, "v", version))
         return false;

llarp/service/tag.cpp

@@ -0,0 +1,13 @@
+#include <llarp/service/tag.hpp>
+
+namespace llarp
+{
+  namespace service
+  {
+    std::string
+    Tag::ToString() const
+    {
+      return std::string((const char *)data());
+    }
+  }  // namespace service
+}  // namespace llarp