Fix various issues in TLS found using BoGo

 - BoGo sends unparseable OCSP responses, so we have to accomodate for
   this by delaying decoding until verification and simply ignoring
   OCSP responses that we can't parse.
 - Check that there is no trailing garbage at the end of various messages.
 - Don't send empty SNI
 - Check the TLS record header versions (previously ignored)
 - For CBC 1/n-1 splitting split every record instead of just first.
   I think this is not a problem but it is what BoGo expects.
 - New Channel::application_protocol virtual (previously was
   implemented on both Client and Server but not shared).
 - Changes to resumption version handling.
 - Fix server version selection when newer versions are disabled.

New policy hooks added in service of BoGo:
 - maximum_certificate_chain_size gives the maximum cert chain in bytes
   that we'll accept.
 - allow_resumption_for_renegotiation specifies if a renegotiation
   attempt can be simply (re-)resumed instead.
 - abort_handshake_on_undesired_renegotiation - previously we just
   ignored it with a warning alert. Now behavior is configurable.
 - request_client_certificate_authentication
 - require_client_certificate_authentication

1 files changed, 8 insertions, 11 deletions

diff --git a/src/lib/tls/msg_cert_status.cpp b/src/lib/tls/msg_cert_status.cpp
index 8ad37336b..c0cd82a28 100644
--- a/src/lib/tls/msg_cert_status.cpp
+++ b/src/lib/tls/msg_cert_status.cpp
@@ -22,8 +22,8 @@ Certificate_Status::Certificate_Status(const std::vector<uint8_t>& buf)
    if(buf.size() < 5)
       throw Decoding_Error("Invalid Certificate_Status message: too small");
 
-   if(buf[0] != 1)
-      throw Decoding_Error("Unexpected Certificate_Status message: unexpected message type");
+   if(buf[0] != 1) // not OCSP
+      throw Decoding_Error("Unexpected Certificate_Status message: unexpected response type");
 
    size_t len = make_uint32(0, buf[1], buf[2], buf[3]);
 
@@ -31,33 +31,30 @@ Certificate_Status::Certificate_Status(const std::vector<uint8_t>& buf)
    if(buf.size() != len + 4)
       throw Decoding_Error("Invalid Certificate_Status: invalid length field");
 
-   m_response = std::make_shared<OCSP::Response>(buf.data() + 4, buf.size() - 4);
+   m_response.assign(buf.begin() + 4, buf.end());
    }
 
 Certificate_Status::Certificate_Status(Handshake_IO& io,
                                        Handshake_Hash& hash,
                                        std::shared_ptr<const OCSP::Response> ocsp) :
-   m_response(ocsp)
+   m_response(ocsp->raw_bits())
    {
    hash.update(io.send(*this));
    }
 
 std::vector<uint8_t> Certificate_Status::serialize() const
    {
-   BOTAN_ASSERT_NONNULL(m_response);
-   const std::vector<uint8_t>& m_resp_bits = m_response->raw_bits();
-
-   if(m_resp_bits.size() > 0xFFFFFF) // unlikely
+   if(m_response.size() > 0xFFFFFF) // unlikely
       throw Encoding_Error("OCSP response too long to encode in TLS");
 
-   const uint32_t m_resp_bits_len = static_cast<uint32_t>(m_resp_bits.size());
+   const uint32_t m_response_len = static_cast<uint32_t>(m_response.size());
 
    std::vector<uint8_t> buf;
    buf.push_back(1); // type OCSP
    for(size_t i = 1; i < 4; ++i)
-      buf[i] = get_byte(i, m_resp_bits_len);
+      buf[i] = get_byte(i, m_response_len);
 
-   buf += m_resp_bits;
+   buf += m_response;
    return buf;
    }