Merge GH #1316 Various TLS fixes

4 files changed, 24 insertions, 9 deletions

diff --git a/src/lib/tls/msg_client_kex.cpp b/src/lib/tls/msg_client_kex.cpp
index 742fee6b5..51040e479 100644
--- a/src/lib/tls/msg_client_kex.cpp
+++ b/src/lib/tls/msg_client_kex.cpp
@@ -403,17 +403,21 @@ Client_Key_Exchange::Client_Key_Exchange(const std::vector<uint8_t>& contents,
             throw Internal_Error("Expected key agreement key type but got " +
                                  private_key.algo_name());
 
+         std::vector<uint8_t> client_pubkey;
+
+         if(ka_key->algo_name() == "DH")
+            {
+            client_pubkey = reader.get_range<uint8_t>(2, 0, 65535);
+            }
+         else
+            {
+            client_pubkey = reader.get_range<uint8_t>(1, 1, 255);
+            }
+
          try
             {
             PK_Key_Agreement ka(*ka_key, rng, "Raw");
 
-            std::vector<uint8_t> client_pubkey;
-
-            if(ka_key->algo_name() == "DH")
-               client_pubkey = reader.get_range<uint8_t>(2, 0, 65535);
-            else
-               client_pubkey = reader.get_range<uint8_t>(1, 0, 255);
-
             secure_vector<uint8_t> shared_secret = ka.derive_key(0, client_pubkey).bits_of();
 
             if(ka_key->algo_name() == "DH")
diff --git a/src/lib/tls/tls_client.cpp b/src/lib/tls/tls_client.cpp
index ce19f04c9..0e620a279 100644
--- a/src/lib/tls/tls_client.cpp
+++ b/src/lib/tls/tls_client.cpp
@@ -330,7 +330,13 @@ void Client::process_handshake_msg(const Handshake_State* active_state,
          if(state.version() > state.client_hello()->version())
             {
             throw TLS_Exception(Alert::HANDSHAKE_FAILURE,
-                                "Server replied with later version than in hello");
+                                "Server replied with later version than client offered");
+            }
+
+         if(state.version().major_version() == 3 && state.version().minor_version() == 0)
+            {
+            throw TLS_Exception(Alert::PROTOCOL_VERSION,
+                                "Server attempting to negotiate SSLv3 which is not supported");
             }
 
          if(!policy().acceptable_protocol_version(state.version()))
diff --git a/src/lib/tls/tls_extensions.cpp b/src/lib/tls/tls_extensions.cpp
index 8f13b2c6d..d521f6bf8 100644
--- a/src/lib/tls/tls_extensions.cpp
+++ b/src/lib/tls/tls_extensions.cpp
@@ -586,7 +586,7 @@ Signature_Algorithms::Signature_Algorithms(TLS_Data_Reader& reader,
    {
    uint16_t len = reader.get_uint16_t();
 
-   if(len + 2 != extension_size)
+   if(len + 2 != extension_size || len % 2 == 1 || len == 0)
       throw Decoding_Error("Bad encoding on signature algorithms extension");
 
    while(len)
diff --git a/src/lib/tls/tls_server.cpp b/src/lib/tls/tls_server.cpp
index f20e363cf..66a0e0e1d 100644
--- a/src/lib/tls/tls_server.cpp
+++ b/src/lib/tls/tls_server.cpp
@@ -405,6 +405,11 @@ void Server::process_client_hello_msg(const Handshake_State* active_state,
    pending_state.client_hello(new Client_Hello(contents));
    const Protocol_Version client_version = pending_state.client_hello()->version();
 
+   if(client_version.major_version() < 3)
+      throw TLS_Exception(Alert::PROTOCOL_VERSION, "Client offered version with major version under 3");
+   if(client_version.major_version() == 3 && client_version.minor_version() == 0)
+      throw TLS_Exception(Alert::PROTOCOL_VERSION, "SSLv3 is not supported");
+
    Protocol_Version negotiated_version;
 
    const Protocol_Version latest_supported =