3 files changed, 59 insertions, 13 deletions

diff --git a/src/lib/tls/tls_extensions.cpp b/src/lib/tls/tls_extensions.cpp
index 6497c3c11..522cf4a4f 100644
--- a/src/lib/tls/tls_extensions.cpp
+++ b/src/lib/tls/tls_extensions.cpp
@@ -59,7 +59,8 @@ Extension* make_extension(TLS_Data_Reader& reader, uint16_t code, uint16_t size)
          return new Session_Ticket(reader, size);
       }
 
-   return nullptr; // not known
+   return new Unknown_Extension(static_cast<Handshake_Extension_Type>(code),
+                                reader, size);
    }
 
 }
@@ -82,10 +83,7 @@ void Extensions::deserialize(TLS_Data_Reader& reader)
                                           extension_code,
                                           extension_size);
 
-         if(extn)
-            this->add(extn);
-         else // unknown/unhandled extension
-            reader.discard_next(extension_size);
+         this->add(extn);
          }
       }
    }
@@ -141,6 +139,19 @@ std::set<Handshake_Extension_Type> Extensions::extension_types() const
    return offers;
    }
 
+Unknown_Extension::Unknown_Extension(Handshake_Extension_Type type,
+                                     TLS_Data_Reader& reader,
+                                     uint16_t extension_size) :
+   m_type(type),
+   m_value(reader.get_fixed<uint8_t>(extension_size))
+   {
+   }
+
+std::vector<uint8_t> Unknown_Extension::serialize() const
+   {
+   throw Invalid_State("Cannot encode an unknown TLS extension");
+   }
+
 Server_Name_Indicator::Server_Name_Indicator(TLS_Data_Reader& reader,
                                              uint16_t extension_size)
    {
diff --git a/src/lib/tls/tls_extensions.h b/src/lib/tls/tls_extensions.h
index 7b7b645bf..114b16489 100644
--- a/src/lib/tls/tls_extensions.h
+++ b/src/lib/tls/tls_extensions.h
@@ -432,6 +432,30 @@ class Certificate_Status_Request final : public Extension
    };
 
 /**
+* Unknown extensions are deserialized as this type
+*/
+class BOTAN_UNSTABLE_API Unknown_Extension final : public Extension
+   {
+   public:
+      Unknown_Extension(Handshake_Extension_Type type,
+                        TLS_Data_Reader& reader,
+                        uint16_t extension_size);
+
+      std::vector<uint8_t> serialize() const override; // always fails
+
+      const std::vector<uint8_t>& value() { return m_value; }
+
+      bool empty() const { return false; }
+
+      Handshake_Extension_Type type() const { return m_type; }
+
+   private:
+      Handshake_Extension_Type m_type;
+      std::vector<uint8_t> m_value;
+
+   };
+
+/**
 * Represents a block of extensions in a hello message
 */
 class BOTAN_UNSTABLE_API Extensions final
@@ -442,13 +466,7 @@ class BOTAN_UNSTABLE_API Extensions final
       template<typename T>
       T* get() const
          {
-         Handshake_Extension_Type type = T::static_type();
-
-         auto i = m_extensions.find(type);
-
-         if(i != m_extensions.end())
-            return dynamic_cast<T*>(i->second.get());
-         return nullptr;
+         return dynamic_cast<T*>(get(T::static_type()));
          }
 
       template<typename T>
@@ -462,6 +480,15 @@ class BOTAN_UNSTABLE_API Extensions final
          m_extensions[extn->type()].reset(extn);
          }
 
+      Extension* get(Handshake_Extension_Type type) const
+         {
+         auto i = m_extensions.find(type);
+
+         if(i != m_extensions.end())
+            return i->second.get();
+         return nullptr;
+         }
+
       std::vector<uint8_t> serialize() const;
 
       void deserialize(TLS_Data_Reader& reader);
diff --git a/src/lib/tls/tls_server.h b/src/lib/tls/tls_server.h
index eb6e710e1..7c5d9668f 100644
--- a/src/lib/tls/tls_server.h
+++ b/src/lib/tls/tls_server.h
@@ -96,12 +96,20 @@ class BOTAN_PUBLIC_API(2,0) Server final : public Channel
 
       /**
       * Return the protocol notification set by the client (using the
-      * NPN extension) for this connection, if any. This value is not
+      * ALPN extension) for this connection, if any. This value is not
       * tied to the session and a later renegotiation of the same
       * session can choose a new protocol.
       */
       std::string next_protocol() const { return m_next_protocol; }
 
+      /**
+      * Return the protocol notification set by the client (using the
+      * ALPN extension) for this connection, if any. This value is not
+      * tied to the session and a later renegotiation of the same
+      * session can choose a new protocol.
+      */
+      std::string application_protocol() const { return m_next_protocol; }
+
    private:
       std::vector<X509_Certificate>
          get_peer_cert_chain(const Handshake_State& state) const override;