Botan::TLS::Server_Hello_Internal Class Reference

#include <tls_messages_internal.h>

Public Member Functions
uint16_t	ciphersuite () const
uint8_t	comp_method () const
Extensions &	extensions ()
const Extensions &	extensions () const
bool	is_hello_retry_request () const
Protocol_Version	legacy_version () const
const std::vector< uint8_t > &	random () const
	Server_Hello_Internal (const std::vector< uint8_t > &buf)
	Server_Hello_Internal (Protocol_Version lv, Session_ID sid, std::vector< uint8_t > r, const uint16_t cs, const uint8_t cm, bool is_hrr=false)
const Session_ID &	session_id () const
Protocol_Version	version () const

Detailed Description

Version-agnostic internal server hello data container that allows parsing Server_Hello messages without prior knowledge of the contained protocol version.

Definition at line 110 of file tls_messages_internal.h.

Constructor & Destructor Documentation

Server_Hello_Internal() [1/2]

Botan::TLS::Server_Hello_Internal::Server_Hello_Internal ( const std::vector< uint8_t > & buf )

explicit

Deserialize a Server Hello message

Definition at line 49 of file msg_server_hello.cpp.

                                                                          {
   if(buf.size() < 38) {
      throw Decoding_Error("Server_Hello: Packet corrupted");
   }
 
   TLS_Data_Reader reader("ServerHello", buf);
 
   const uint8_t major_version = reader.get_byte();
   const uint8_t minor_version = reader.get_byte();
 
   m_legacy_version = Protocol_Version(major_version, minor_version);
 
   // RFC 8446 4.1.3
   //    Upon receiving a message with type server_hello, implementations MUST
   //    first examine the Random value and, if it matches this value, process
   //    it as described in Section 4.1.4 [Hello Retry Request]).
   m_random = reader.get_fixed<uint8_t>(32);
   m_is_hello_retry_request = CT::is_equal<uint8_t>(m_random, HELLO_RETRY_REQUEST_MARKER).as_bool();
 
   m_session_id = Session_ID(reader.get_range<uint8_t>(1, 0, 32));
   m_ciphersuite = reader.get_uint16_t();
   m_comp_method = reader.get_byte();
 
   // Note that this code path might parse a TLS 1.2 (or older) server hello message that
   // is nevertheless marked as being a 'hello retry request' (potentially maliciously).
   // Extension parsing will however not be affected by the associated flag.
   // Only after parsing the extensions will the upstream code be able to decide
   // whether we're dealing with TLS 1.3 or older.
   m_extensions.deserialize(reader,
                            Connection_Side::Server,
                            m_is_hello_retry_request ? Handshake_Type::HelloRetryRequest : Handshake_Type::ServerHello);
}

References Botan::TLS::TLS_Data_Reader::get_byte(), Botan::TLS::TLS_Data_Reader::get_fixed(), Botan::TLS::TLS_Data_Reader::get_range(), Botan::TLS::TLS_Data_Reader::get_uint16_t(), Botan::TLS::HELLO_RETRY_REQUEST_MARKER, Botan::TLS::HelloRetryRequest, Botan::CT::is_equal(), Botan::TLS::Server, and Botan::TLS::ServerHello.

Server_Hello_Internal() [2/2]

Botan::TLS::Server_Hello_Internal::Server_Hello_Internal ( Protocol_Version lv, Session_ID sid, std::vector< uint8_t > r, const uint16_t cs, const uint8_t cm, bool is_hrr = false )

inline

Definition at line 117 of file tls_messages_internal.h.

                                                 :
            m_legacy_version(lv),
            m_session_id(std::move(sid)),
            m_random(std::move(r)),
            m_is_hello_retry_request(is_hrr),
            m_ciphersuite(cs),
            m_comp_method(cm) {}

Member Function Documentation

ciphersuite()

uint16_t Botan::TLS::Server_Hello_Internal::ciphersuite ( ) const

inline

Definition at line 138 of file tls_messages_internal.h.

{ return m_ciphersuite; }

comp_method()

uint8_t Botan::TLS::Server_Hello_Internal::comp_method ( ) const

inline

Definition at line 140 of file tls_messages_internal.h.

{ return m_comp_method; }

extensions() [1/2]

Extensions & Botan::TLS::Server_Hello_Internal::extensions ( )

inline

Definition at line 146 of file tls_messages_internal.h.

{ return m_extensions; }

extensions() [2/2]

const Extensions & Botan::TLS::Server_Hello_Internal::extensions ( ) const

inline

Definition at line 144 of file tls_messages_internal.h.

{ return m_extensions; }

Referenced by version().

is_hello_retry_request()

bool Botan::TLS::Server_Hello_Internal::is_hello_retry_request ( ) const

inline

Definition at line 142 of file tls_messages_internal.h.

{ return m_is_hello_retry_request; }

legacy_version()

Protocol_Version Botan::TLS::Server_Hello_Internal::legacy_version ( ) const

inline

Definition at line 132 of file tls_messages_internal.h.

{ return m_legacy_version; }

random()

const std::vector< uint8_t > & Botan::TLS::Server_Hello_Internal::random ( ) const

inline

Definition at line 136 of file tls_messages_internal.h.

{ return m_random; }

session_id()

const Session_ID & Botan::TLS::Server_Hello_Internal::session_id ( ) const

inline

Definition at line 134 of file tls_messages_internal.h.

{ return m_session_id; }

version()

Protocol_Version Botan::TLS::Server_Hello_Internal::version

(

)

const

Definition at line 82 of file msg_server_hello.cpp.

                                                      {
   // RFC 8446 4.2.1
   //    A server which negotiates a version of TLS prior to TLS 1.3 MUST set
   //    ServerHello.version and MUST NOT send the "supported_versions"
   //    extension.  A server which negotiates TLS 1.3 MUST respond by sending
   //    a "supported_versions" extension containing the selected version
   //    value (0x0304).
   //
   // Note: Here we just take a message parsing decision, further validation of
   //       the extension's contents is done later.
   return (extensions().has<Supported_Versions>()) ? Protocol_Version::TLS_V13 : m_legacy_version;
}

References extensions().

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The documentation for this class was generated from the following files:

• src/lib/tls/tls_messages_internal.h
• src/lib/tls/msg_server_hello.cpp