Revert: No backward compatibility for TLS sessions

src/lib/tls/tls_session.cpp

@@ -137,13 +137,10 @@ Session::Session(const uint8_t ber[], size_t ber_len)
    size_t compression_method = 0;
    uint16_t ciphersuite_code = 0;
 
-   size_t struct_version = 0;
-
-   BER_Decoder dec(ber, ber_len);
-   auto seqdec = dec.start_sequence();
-
-   seqdec
-        .decode_integer_type(struct_version)
+   BER_Decoder(ber, ber_len)
+      .start_sequence()
+        .decode_and_check(static_cast<size_t>(TLS_SESSION_PARAM_STRUCT_VERSION),
+                          "Unknown version in serialized TLS session")
         .decode_integer_type(start_time)
         .decode_integer_type(major_version)
         .decode_integer_type(minor_version)
@@ -161,35 +158,13 @@ Session::Session(const uint8_t ber[], size_t ber_len)
         .decode(server_service)
         .decode(server_port)
         .decode(srp_identifier_str)
-        .decode(srtp_profile);
-
-   m_version = Protocol_Version(major_version, minor_version);
-
-   if(struct_version == TLS_SESSION_PARAM_STRUCT_VERSION_TLS12)
-      {
-      if(!m_version.is_pre_tls_13())
-         throw Decoding_Error("Serialized TLS session scheme does not match the protocol version expectations");
-
-      m_early_data_allowed = false;
-      m_max_early_data_bytes = 0;
-      m_ticket_age_add = 0;
-      m_lifetime_hint = 0;
-      }
-   else if(struct_version == TLS_SESSION_PARAM_STRUCT_VERSION_TLS13)
-      {
-      seqdec
-         .decode(m_early_data_allowed)
-         .decode_integer_type(m_max_early_data_bytes)
-         .decode_integer_type(m_ticket_age_add)
-         .decode_integer_type(m_lifetime_hint);
-      }
-   else
-      {
-      throw Decoding_Error("Unknown TLS Session object revision: " + std::to_string(struct_version));
-      }
-
-   seqdec.end_cons();
-   dec.verify_end();
+        .decode(srtp_profile)
+        .decode(m_early_data_allowed)
+        .decode_integer_type(m_max_early_data_bytes)
+        .decode_integer_type(m_ticket_age_add)
+        .decode_integer_type(m_lifetime_hint)
+      .end_cons()
+      .verify_end();
 
    /*
    * Compression is not supported and must be zero
@@ -216,6 +191,7 @@ Session::Session(const uint8_t ber[], size_t ber_len)
       }
 
    m_ciphersuite = ciphersuite_code;
+   m_version = Protocol_Version(major_version, minor_version);
    m_start_time = std::chrono::system_clock::from_time_t(start_time);
    m_connection_side = static_cast<Connection_Side>(side_code);
    m_srtp_profile = static_cast<uint16_t>(srtp_profile);
@@ -245,7 +221,7 @@ secure_vector<uint8_t> Session::DER_encode() const
 
    return DER_Encoder()
       .start_sequence()
-         .encode(static_cast<size_t>(TLS_SESSION_PARAM_STRUCT_VERSION_TLS13))
+         .encode(static_cast<size_t>(TLS_SESSION_PARAM_STRUCT_VERSION))
          .encode(static_cast<size_t>(std::chrono::system_clock::to_time_t(m_start_time)))
          .encode(static_cast<size_t>(m_version.major_version()))
          .encode(static_cast<size_t>(m_version.minor_version()))

src/lib/tls/tls_session.h

@@ -211,8 +211,7 @@ class BOTAN_PUBLIC_API(2,0) Session final
       //              - m_lifetime_hint
       enum
          {
-         TLS_SESSION_PARAM_STRUCT_VERSION_TLS12 = 20160812,
-         TLS_SESSION_PARAM_STRUCT_VERSION_TLS13 = 20220505
+         TLS_SESSION_PARAM_STRUCT_VERSION = 20220505
          };
 
       std::chrono::system_clock::time_point m_start_time;

src/tests/test_tls.cpp

@@ -29,22 +29,6 @@ namespace Botan_Tests {
 
 class TLS_Session_Tests final : public Test
    {
-   private:
-      std::string session_rev20160812 =
-         "-----BEGIN TLS SESSION-----\n"
-         "MIICCQIEATOhLAIEYoOgCgIBAwIBAwQCqrsEEEJCQkJCQkJCQkJCQkJCQkICAwDA\n"
-         "LwIBAAIBAQIBAAEB/wEBAAQCEAIEggG2MIIBsjCCARugAwIBAgIBATANBgkqhkiG\n"
-         "9w0BAQsFADARMQ8wDQYDVQQDEwZjbGllbnQwHhcNMTYwNzMwMDEyMzU5WhcNMjYw\n"
-         "NzMwMDEyMzU5WjARMQ8wDQYDVQQDEwZjbGllbnQwgZ8wDQYJKoZIhvcNAQEBBQAD\n"
-         "gY0AMIGJAoGBAMOBdeAEpo0JP4I7nDedIB+8C7ehx5GQXj+/doR+ROdR67zTYL2U\n"
-         "XIHlIivMiEbTqKD5Ppv1vrq9ku3x3h/xkCFwPnq2wJAVE/l+ObER8JyTSJcceyEZ\n"
-         "hKdUzUX+CVrw6kI2gpvM96f+myiI54q0d2kKW54cy+kcakoPl6fgKEIBAgMBAAGj\n"
-         "GjAYMAkGA1UdEwQCMAAwCwYDVR0PBAQDAgeAMA0GCSqGSIb3DQEBCwUAA4GBABp6\n"
-         "WgGFMrAirwdn1IYWDP8tFnoZFdI4NbVFlJFtxoC+XS5iYHbF1Sci68x3XX2Z+YC+\n"
-         "L8lNNKz2zAC6kMvPsGCKoefjlx7wwHpB1HrYNF0fgf5Bihz0EFRCn9IXvXd9wc8I\n"
-         "8F35B5nGWTYeDxqO5KwPeJdCC9vII9qAovK6IwgcDANyc2EMAAIBAAwAAgEA\n"
-         "-----END TLS SESSION-----\n";
-
    public:
       std::vector<Test::Result> run() override
          {
@@ -121,22 +105,6 @@ class TLS_Session_Tests final : public Test
                             "Serialized TLS session contains unknown cipher suite (47789)",
                             [&] { Botan::TLS::Session{pem_with_unknown_ciphersuite}; });
 
-         Botan::TLS::Session legacy_session(session_rev20160812);
-
-         // check a few fields that were present in this revision already
-         result.confirm("protocol version", legacy_session.version().is_pre_tls_13());
-         result.test_eq("master secret", legacy_session.master_secret(), Botan::secure_vector<uint8_t>{0x10, 0x02});
-         result.confirm("encrypt_then_mac", legacy_session.supports_extended_master_secret());
-         result.test_eq("peer certificate", legacy_session.peer_certs().at(0).subject_info("CN").at(0), "client");
-         result.test_eq("ticket", legacy_session.session_ticket(), std::vector<uint8_t>(16, 0x42));
-         result.test_is_eq("SRTP profile", legacy_session.dtls_srtp_profile(), uint16_t(0x0000));
-
-         // check newly added fields (default values are added)
-         result.confirm("no early data", !legacy_session.supports_early_data());
-         result.test_is_eq("no early data bytes", legacy_session.max_early_data_bytes(), uint32_t(0));
-         result.test_is_eq("no age adder", legacy_session.session_age_add(), uint32_t(0));
-         result.confirm("no lifetime hint", legacy_session.lifetime_hint().count() == 0);
-
          return {result};
          }
    };