diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/bogo_shim/bogo_shim.cpp | 5 | ||||
-rw-r--r-- | src/lib/tls/msg_client_hello.cpp | 19 | ||||
-rw-r--r-- | src/lib/tls/msg_hello_verify.cpp | 5 | ||||
-rw-r--r-- | src/lib/tls/tls_callbacks.cpp | 5 | ||||
-rw-r--r-- | src/lib/tls/tls_callbacks.h | 12 | ||||
-rw-r--r-- | src/lib/tls/tls_client.cpp | 1 | ||||
-rw-r--r-- | src/lib/tls/tls_handshake_io.cpp | 8 | ||||
-rw-r--r-- | src/lib/tls/tls_handshake_state.cpp | 14 | ||||
-rw-r--r-- | src/lib/tls/tls_messages.h | 6 | ||||
-rw-r--r-- | src/lib/tls/tls_server.cpp | 42 | ||||
-rw-r--r-- | src/tests/unit_tls.cpp | 5 |
11 files changed, 112 insertions, 10 deletions
diff --git a/src/bogo_shim/bogo_shim.cpp b/src/bogo_shim/bogo_shim.cpp index 64fedf57f..ec4af181e 100644 --- a/src/bogo_shim/bogo_shim.cpp +++ b/src/bogo_shim/bogo_shim.cpp @@ -1170,6 +1170,11 @@ class Shim_Credentials final : public Botan::Credentials_Manager return Botan::SymmetricKey("ABCDEF0123456789"); } + if(type == "tls-server" && context == "dtls-cookie-secret") + { + return Botan::SymmetricKey("F00FB00FD00F100F700F"); + } + if(identity != m_psk_identity) throw Shim_Exception("Unexpected PSK identity"); return m_psk; diff --git a/src/lib/tls/msg_client_hello.cpp b/src/lib/tls/msg_client_hello.cpp index a3e1206df..149f3f0d4 100644 --- a/src/lib/tls/msg_client_hello.cpp +++ b/src/lib/tls/msg_client_hello.cpp @@ -259,6 +259,25 @@ std::vector<uint8_t> Client_Hello::serialize() const return buf; } +std::vector<uint8_t> Client_Hello::cookie_input_data() const + { + std::vector<uint8_t> buf; + + buf.push_back(m_version.major_version()); + buf.push_back(m_version.minor_version()); + buf += m_random; + + append_tls_length_value(buf, m_session_id, 1); + + append_tls_length_value(buf, m_suites, 2); + append_tls_length_value(buf, m_comp_methods, 1); + + // Here we don't serialize the extensions since the client extensions + // may contain values we don't know how to serialize back. + + return buf; + } + /* * Read a counterparty client hello */ diff --git a/src/lib/tls/msg_hello_verify.cpp b/src/lib/tls/msg_hello_verify.cpp index 648ca1a4e..bc93af9d6 100644 --- a/src/lib/tls/msg_hello_verify.cpp +++ b/src/lib/tls/msg_hello_verify.cpp @@ -35,7 +35,7 @@ Hello_Verify_Request::Hello_Verify_Request(const std::vector<uint8_t>& client_he const std::string& client_identity, const SymmetricKey& secret_key) { - std::unique_ptr<MessageAuthenticationCode> hmac(MessageAuthenticationCode::create("HMAC(SHA-256)")); + std::unique_ptr<MessageAuthenticationCode> hmac = MessageAuthenticationCode::create_or_throw("HMAC(SHA-256)"); hmac->set_key(secret_key); hmac->update_be(static_cast<uint64_t>(client_hello_bits.size())); @@ -43,7 +43,8 @@ Hello_Verify_Request::Hello_Verify_Request(const std::vector<uint8_t>& client_he hmac->update_be(static_cast<uint64_t>(client_identity.size())); hmac->update(client_identity); - m_cookie = unlock(hmac->final()); + m_cookie.resize(hmac->output_length()); + hmac->final(m_cookie.data()); } std::vector<uint8_t> Hello_Verify_Request::serialize() const diff --git a/src/lib/tls/tls_callbacks.cpp b/src/lib/tls/tls_callbacks.cpp index bcd3aa39b..18868e0ef 100644 --- a/src/lib/tls/tls_callbacks.cpp +++ b/src/lib/tls/tls_callbacks.cpp @@ -33,6 +33,11 @@ std::string TLS::Callbacks::tls_server_choose_app_protocol(const std::vector<std return ""; } +std::string TLS::Callbacks::tls_peer_network_identity() + { + return ""; + } + void TLS::Callbacks::tls_modify_extensions(Extensions&, Connection_Side) { } diff --git a/src/lib/tls/tls_callbacks.h b/src/lib/tls/tls_callbacks.h index 325ed884b..c9ba070c0 100644 --- a/src/lib/tls/tls_callbacks.h +++ b/src/lib/tls/tls_callbacks.h @@ -314,6 +314,18 @@ class BOTAN_PUBLIC_API(2,0) Callbacks virtual std::string tls_decode_group_param(Group_Params group_param); /** + * Optional callback: return peer network identity + * + * There is no expected or specified format. The only expectation is this + * function will return a unique value. For example returning the peer + * host IP and port. + * + * This is used to bind the DTLS cookie to a particular network identity. + * It is only called if the dtls-cookie-secret PSK is also defined. + */ + virtual std::string tls_peer_network_identity(); + + /** * Optional callback: error logging. (not currently called) * @param err An error message related to this connection. */ diff --git a/src/lib/tls/tls_client.cpp b/src/lib/tls/tls_client.cpp index 7779481bc..12c95595d 100644 --- a/src/lib/tls/tls_client.cpp +++ b/src/lib/tls/tls_client.cpp @@ -279,7 +279,6 @@ void Client::process_handshake_msg(const Handshake_State* active_state, state.set_expected_next(HELLO_VERIFY_REQUEST); // might get it again Hello_Verify_Request hello_verify_request(contents); - state.hello_verify_request(hello_verify_request); } else if(type == SERVER_HELLO) diff --git a/src/lib/tls/tls_handshake_io.cpp b/src/lib/tls/tls_handshake_io.cpp index 7ac868612..62f3bebb8 100644 --- a/src/lib/tls/tls_handshake_io.cpp +++ b/src/lib/tls/tls_handshake_io.cpp @@ -379,7 +379,6 @@ Datagram_Handshake_IO::format(const std::vector<uint8_t>& msg, return format_w_seq(msg, type, m_in_message_seq - 1); } - std::vector<uint8_t> Datagram_Handshake_IO::send(const Handshake_Message& msg) { @@ -392,6 +391,13 @@ Datagram_Handshake_IO::send(const Handshake_Message& msg) m_send_hs(epoch, CHANGE_CIPHER_SPEC, msg_bits); return std::vector<uint8_t>(); // not included in handshake hashes } + else if(msg_type == HELLO_VERIFY_REQUEST) + { + // This message is not included in the handshake hashes + send_message(m_out_message_seq, epoch, msg_type, msg_bits); + m_out_message_seq += 1; + return std::vector<uint8_t>(); + } // Note: not saving CCS, instead we know it was there due to change in epoch m_flights.rbegin()->push_back(m_out_message_seq); diff --git a/src/lib/tls/tls_handshake_state.cpp b/src/lib/tls/tls_handshake_state.cpp index 8bc603a43..8261cefbc 100644 --- a/src/lib/tls/tls_handshake_state.cpp +++ b/src/lib/tls/tls_handshake_state.cpp @@ -203,8 +203,16 @@ void Handshake_State::hello_verify_request(const Hello_Verify_Request& hello_ver void Handshake_State::client_hello(Client_Hello* client_hello) { - m_client_hello.reset(client_hello); - note_message(*m_client_hello); + if(client_hello == nullptr) + { + m_client_hello.reset(); + hash().reset(); + } + else + { + m_client_hello.reset(client_hello); + note_message(*m_client_hello); + } } void Handshake_State::server_hello(Server_Hello* server_hello) @@ -304,9 +312,11 @@ void Handshake_State::confirm_transition_to(Handshake_Type handshake_msg) const bool ok = (m_hand_expecting_mask & mask) != 0; // overlap? if(!ok) + { throw Unexpected_Message("Unexpected state transition in handshake, expected " + handshake_mask_to_string(m_hand_expecting_mask, '|') + " received " + handshake_mask_to_string(m_hand_received_mask, '+')); + } /* We don't know what to expect next, so force a call to set_expected_next; if it doesn't happen, the next transition diff --git a/src/lib/tls/tls_messages.h b/src/lib/tls/tls_messages.h index 7c35bff87..e67b82888 100644 --- a/src/lib/tls/tls_messages.h +++ b/src/lib/tls/tls_messages.h @@ -53,7 +53,7 @@ class BOTAN_UNSTABLE_API Hello_Verify_Request final : public Handshake_Message std::vector<uint8_t> serialize() const override; Handshake_Type type() const override { return HELLO_VERIFY_REQUEST; } - std::vector<uint8_t> cookie() const { return m_cookie; } + const std::vector<uint8_t>& cookie() const { return m_cookie; } explicit Hello_Verify_Request(const std::vector<uint8_t>& buf); @@ -146,6 +146,10 @@ class BOTAN_UNSTABLE_API Client_Hello final : public Handshake_Message void update_hello_cookie(const Hello_Verify_Request& hello_verify); + const std::vector<uint8_t>& cookie() const { return m_hello_cookie; } + + std::vector<uint8_t> cookie_input_data() const; + std::set<Handshake_Extension_Type> extension_types() const { return m_extensions.extension_types(); } diff --git a/src/lib/tls/tls_server.cpp b/src/lib/tls/tls_server.cpp index d2474c225..c0c5e1a5c 100644 --- a/src/lib/tls/tls_server.cpp +++ b/src/lib/tls/tls_server.cpp @@ -493,8 +493,9 @@ void Server::process_client_hello_msg(const Handshake_State* active_state, pending_state.client_hello(new Client_Hello(contents)); const Protocol_Version client_offer = pending_state.client_hello()->version(); + const bool datagram = client_offer.is_datagram_protocol(); - if(client_offer.is_datagram_protocol()) + if(datagram) { if(client_offer.major_version() == 0xFF) throw TLS_Exception(Alert::PROTOCOL_VERSION, "Client offered DTLS version with major version 0xFF"); @@ -507,19 +508,54 @@ void Server::process_client_hello_msg(const Handshake_State* active_state, throw TLS_Exception(Alert::PROTOCOL_VERSION, "SSLv3 is not supported"); } + /* + * BoGo test suite expects that we will send the hello verify with a record + * version matching the version that is eventually negotiated. This is wrong + * but harmless, so go with it. Also doing the version negotiation step first + * allows to immediately close the connection with an alert if the client has + * offered a version that we are not going to negotiate anyway, instead of + * making them first do the cookie exchange and then telling them no. + * + * There is no issue with amplification here, since the alert is just 2 bytes. + */ const Protocol_Version negotiated_version = select_version(policy(), client_offer, active_state ? active_state->version() : Protocol_Version(), pending_state.client_hello()->sent_fallback_scsv(), pending_state.client_hello()->supported_versions()); + pending_state.set_version(negotiated_version); + const auto compression_methods = pending_state.client_hello()->compression_methods(); if(!value_exists(compression_methods, uint8_t(0))) throw TLS_Exception(Alert::ILLEGAL_PARAMETER, "Client did not offer NULL compression"); - secure_renegotiation_check(pending_state.client_hello()); + if(initial_handshake && datagram) + { + SymmetricKey cookie_secret; - pending_state.set_version(negotiated_version); + try + { + cookie_secret = m_creds.psk("tls-server", "dtls-cookie-secret", ""); + } + catch(...) {} + + if(cookie_secret.size() > 0) + { + const std::string client_identity = callbacks().tls_peer_network_identity(); + Hello_Verify_Request verify(pending_state.client_hello()->cookie_input_data(), client_identity, cookie_secret); + + if(pending_state.client_hello()->cookie() != verify.cookie()) + { + pending_state.handshake_io().send(verify); + pending_state.client_hello(nullptr); + pending_state.set_expected_next(CLIENT_HELLO); + return; + } + } + } + + secure_renegotiation_check(pending_state.client_hello()); callbacks().tls_examine_extensions(pending_state.client_hello()->extensions(), CLIENT); diff --git a/src/tests/unit_tls.cpp b/src/tests/unit_tls.cpp index 34c25e9ef..c3355b118 100644 --- a/src/tests/unit_tls.cpp +++ b/src/tests/unit_tls.cpp @@ -176,6 +176,11 @@ class Credentials_Manager_Test final : public Botan::Credentials_Manager return Botan::SymmetricKey("AABBCCDDEEFF012345678012345678"); } + if(type == "tls-server" && context == "dtls-cookie-secret") + { + return Botan::SymmetricKey("4AEA5EAD279CADEB537A594DA0E9DE3A"); + } + if(context == "server.example.com" && type == "tls-client") { return Botan::SymmetricKey("20B602D1475F2DF888FCB60D2AE03AFD"); |