Coverage Report

Created: 2025-04-11 06:34

/src/botan/src/lib/tls/msg_finished.cpp
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Source (jump to first uncovered line)
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/*
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* Finished Message
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* (C) 2004-2006,2012 Jack Lloyd
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*     2021 Elektrobit Automotive GmbH
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*     2022 René Meusel, Hannes Rantzsch - neXenio GmbH
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*
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* Botan is released under the Simplified BSD License (see license.txt)
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*/
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#include <botan/tls_messages.h>
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#include <botan/kdf.h>
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#include <botan/internal/ct_utils.h>
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#include <botan/internal/target_info.h>
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#include <botan/internal/tls_handshake_io.h>
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#include <botan/internal/tls_handshake_state.h>
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#if defined(BOTAN_HAS_TLS_13)
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   #include <botan/internal/tls_cipher_state.h>
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#endif
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namespace Botan::TLS {
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namespace {
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/*
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* Compute the verify_data for TLS 1.2
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*/
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std::vector<uint8_t> finished_compute_verify_12(const Handshake_State& state, Connection_Side side) {
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   const uint8_t TLS_CLIENT_LABEL[] = {
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      0x63, 0x6C, 0x69, 0x65, 0x6E, 0x74, 0x20, 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64};
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   const uint8_t TLS_SERVER_LABEL[] = {
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      0x73, 0x65, 0x72, 0x76, 0x65, 0x72, 0x20, 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64};
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   auto prf = state.protocol_specific_prf();
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   std::vector<uint8_t> input;
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   std::vector<uint8_t> label;
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   label += (side == Connection_Side::Client) ? std::make_pair(TLS_CLIENT_LABEL, sizeof(TLS_CLIENT_LABEL))
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                                              : std::make_pair(TLS_SERVER_LABEL, sizeof(TLS_SERVER_LABEL));
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   input += state.hash().final(state.ciphersuite().prf_algo());
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   return unlock(prf->derive_key(12, state.session_keys().master_secret(), input, label));
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}
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}  // namespace
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std::vector<uint8_t> Finished::serialize() const {
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   return m_verification_data;
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}
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5.34k
Finished::Finished(const std::vector<uint8_t>& buf) : m_verification_data(buf) {}
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std::vector<uint8_t> Finished::verify_data() const {
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   return m_verification_data;
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}
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Finished_12::Finished_12(Handshake_IO& io, Handshake_State& state, Connection_Side side) {
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   m_verification_data = finished_compute_verify_12(state, side);
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   state.hash().update(io.send(*this));
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}
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bool Finished_12::verify(const Handshake_State& state, Connection_Side side) const {
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   std::vector<uint8_t> computed_verify = finished_compute_verify_12(state, side);
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#if defined(BOTAN_UNSAFE_FUZZER_MODE)
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   return true;
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#else
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   // first check the size:
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   if(m_verification_data.size() != computed_verify.size()) {
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      return false;
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   }
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   return CT::is_equal(m_verification_data.data(), computed_verify.data(), computed_verify.size()).as_bool();
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#endif
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}
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#if defined(BOTAN_HAS_TLS_13)
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Finished_13::Finished_13(Cipher_State* cipher_state, const Transcript_Hash& transcript_hash) {
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   m_verification_data = cipher_state->finished_mac(transcript_hash);
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}
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bool Finished_13::verify(Cipher_State* cipher_state, const Transcript_Hash& transcript_hash) const {
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   return cipher_state->verify_peer_finished_mac(transcript_hash, m_verification_data);
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}
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#endif
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}  // namespace Botan::TLS