1 files changed, 321 insertions, 0 deletions
diff --git a/src/tls/tls_extensions.h b/src/tls/tls_extensions.h
new file mode 100644
index 000000000..180216b8b
--- /dev/null
+++ b/src/tls/tls_extensions.h
@@ -0,0 +1,321 @@
+/*
+* TLS Extensions
+* (C) 2011 Jack Lloyd
+*
+* Released under the terms of the Botan license
+*/
+
+#ifndef BOTAN_TLS_EXTENSIONS_H__
+#define BOTAN_TLS_EXTENSIONS_H__
+
+#include <botan/secmem.h>
+#include <botan/tls_magic.h>
+#include <vector>
+#include <string>
+#include <map>
+
+namespace Botan {
+
+namespace TLS {
+
+class TLS_Data_Reader;
+
+enum Handshake_Extension_Type {
+   TLSEXT_SERVER_NAME_INDICATION = 0,
+   TLSEXT_MAX_FRAGMENT_LENGTH    = 1,
+   TLSEXT_CLIENT_CERT_URL        = 2,
+   TLSEXT_TRUSTED_CA_KEYS        = 3,
+   TLSEXT_TRUNCATED_HMAC         = 4,
+
+   TLSEXT_CERTIFICATE_TYPES      = 9,
+   TLSEXT_USABLE_ELLIPTIC_CURVES = 10,
+   TLSEXT_EC_POINT_FORMATS       = 11,
+   TLSEXT_SRP_IDENTIFIER         = 12,
+   TLSEXT_SIGNATURE_ALGORITHMS   = 13,
+
+   TLSEXT_SESSION_TICKET         = 35,
+
+   TLSEXT_NEXT_PROTOCOL          = 13172,
+
+   TLSEXT_SAFE_RENEGOTIATION     = 65281,
+};
+
+/**
+* Base class representing a TLS extension of some kind
+*/
+class Extension
+   {
+   public:
+      virtual Handshake_Extension_Type type() const = 0;
+
+      virtual MemoryVector<byte> serialize() const = 0;
+
+      virtual bool empty() const = 0;
+
+      virtual ~Extension() {}
+   };
+
+/**
+* Server Name Indicator extension (RFC 3546)
+*/
+class Server_Name_Indicator : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_SERVER_NAME_INDICATION; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      Server_Name_Indicator(const std::string& host_name) :
+         sni_host_name(host_name) {}
+
+      Server_Name_Indicator(TLS_Data_Reader& reader,
+                            u16bit extension_size);
+
+      std::string host_name() const { return sni_host_name; }
+
+      MemoryVector<byte> serialize() const;
+
+      bool empty() const { return sni_host_name == ""; }
+   private:
+      std::string sni_host_name;
+   };
+
+/**
+* SRP identifier extension (RFC 5054)
+*/
+class SRP_Identifier : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_SRP_IDENTIFIER; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      SRP_Identifier(const std::string& identifier) :
+         srp_identifier(identifier) {}
+
+      SRP_Identifier(TLS_Data_Reader& reader,
+                     u16bit extension_size);
+
+      std::string identifier() const { return srp_identifier; }
+
+      MemoryVector<byte> serialize() const;
+
+      bool empty() const { return srp_identifier == ""; }
+   private:
+      std::string srp_identifier;
+   };
+
+/**
+* Renegotiation Indication Extension (RFC 5746)
+*/
+class Renegotation_Extension : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_SAFE_RENEGOTIATION; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      Renegotation_Extension() {}
+
+      Renegotation_Extension(const MemoryRegion<byte>& bits) :
+         reneg_data(bits) {}
+
+      Renegotation_Extension(TLS_Data_Reader& reader,
+                             u16bit extension_size);
+
+      const MemoryVector<byte>& renegotiation_info() const
+         { return reneg_data; }
+
+      MemoryVector<byte> serialize() const;
+
+      bool empty() const { return false; } // always send this
+   private:
+      MemoryVector<byte> reneg_data;
+   };
+
+/**
+* Maximum Fragment Length Negotiation Extension (RFC 4366 sec 3.2)
+*/
+class Maximum_Fragment_Length : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_MAX_FRAGMENT_LENGTH; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      bool empty() const { return val != 0; }
+
+      size_t fragment_size() const;
+
+      MemoryVector<byte> serialize() const
+         {
+         return MemoryVector<byte>(&val, 1);
+         }
+
+      /**
+      * @param max_fragment specifies what maximum fragment size to
+      *        advertise. Currently must be one of 512, 1024, 2048, or
+      *        4096.
+      */
+      Maximum_Fragment_Length(size_t max_fragment);
+
+      Maximum_Fragment_Length(TLS_Data_Reader& reader,
+                              u16bit extension_size);
+
+   private:
+      byte val;
+   };
+
+/**
+* Next Protocol Negotiation
+* http://technotes.googlecode.com/git/nextprotoneg.html
+*
+* This implementation requires the semantics defined in the Google
+* spec (implemented in Chromium); the internet draft leaves the format
+* unspecified.
+*/
+class Next_Protocol_Notification : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_NEXT_PROTOCOL; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      const std::vector<std::string>& protocols() const
+         { return m_protocols; }
+
+      /**
+      * Empty extension, used by client
+      */
+      Next_Protocol_Notification() {}
+
+      /**
+      * List of protocols, used by server
+      */
+      Next_Protocol_Notification(const std::vector<std::string>& protocols) :
+         m_protocols(protocols) {}
+
+      Next_Protocol_Notification(TLS_Data_Reader& reader,
+                                 u16bit extension_size);
+
+      MemoryVector<byte> serialize() const;
+
+      bool empty() const { return false; }
+   private:
+      std::vector<std::string> m_protocols;
+   };
+
+/**
+* Supported Elliptic Curves Extension (RFC 4492)
+*/
+class Supported_Elliptic_Curves : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_USABLE_ELLIPTIC_CURVES; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      static std::string curve_id_to_name(u16bit id);
+      static u16bit name_to_curve_id(const std::string& name);
+
+      const std::vector<std::string>& curves() const { return m_curves; }
+
+      MemoryVector<byte> serialize() const;
+
+      Supported_Elliptic_Curves(const std::vector<std::string>& curves) :
+         m_curves(curves) {}
+
+      Supported_Elliptic_Curves(TLS_Data_Reader& reader,
+                                u16bit extension_size);
+
+      bool empty() const { return m_curves.empty(); }
+   private:
+      std::vector<std::string> m_curves;
+   };
+
+/**
+* Signature Algorithms Extension for TLS 1.2 (RFC 5246)
+*/
+class Signature_Algorithms : public Extension
+   {
+   public:
+      static Handshake_Extension_Type static_type()
+         { return TLSEXT_SIGNATURE_ALGORITHMS; }
+
+      Handshake_Extension_Type type() const { return static_type(); }
+
+      static std::string hash_algo_name(byte code);
+      static byte hash_algo_code(const std::string& name);
+
+      static std::string sig_algo_name(byte code);
+      static byte sig_algo_code(const std::string& name);
+
+      std::vector<std::pair<std::string, std::string> >
+         supported_signature_algorthms() const
+         {
+         return m_supported_algos;
+         }
+
+      MemoryVector<byte> serialize() const;
+
+      bool empty() const { return false; }
+
+      Signature_Algorithms(const std::vector<std::pair<std::string, std::string> >& algos) :
+         m_supported_algos(algos) {}
+
+      Signature_Algorithms(TLS_Data_Reader& reader,
+                           u16bit extension_size);
+   private:
+      std::vector<std::pair<std::string, std::string> > m_supported_algos;
+   };
+
+/**
+* Represents a block of extensions in a hello message
+*/
+class Extensions
+   {
+   public:
+      template<typename T>
+      T* get() const
+         {
+         Handshake_Extension_Type type = T::static_type();
+
+         std::map<Handshake_Extension_Type, Extension*>::const_iterator i =
+            extensions.find(type);
+
+         if(i != extensions.end())
+            return dynamic_cast<T*>(i->second);
+         return 0;
+         }
+
+      void add(Extension* extn)
+         {
+         delete extensions[extn->type()]; // or hard error if already exists?
+         extensions[extn->type()] = extn;
+         }
+
+      MemoryVector<byte> serialize() const;
+
+      Extensions() {}
+
+      Extensions(TLS_Data_Reader& reader); // deserialize
+
+      ~Extensions();
+   private:
+      Extensions(const Extensions&) {}
+      Extensions& operator=(const Extensions&) { return (*this); }
+
+      std::map<Handshake_Extension_Type, Extension*> extensions;
+   };
+
+}
+
+}
+
+#endif