Enabling daemon-rpc SSL now requires non-system CA verification

If `--daemon-ssl enabled` is set in the wallet, then a user certificate,
fingerprint, or onion/i2p address must be provided.

contrib/epee/include/net/net_ssl.h

@@ -100,6 +100,9 @@ namespace net_utils
     //! \return False iff ssl is disabled, otherwise true.
     explicit operator bool() const noexcept { return support != ssl_support_t::e_ssl_support_disabled; }
 
+    //! \retrurn True if `host` can be verified using `this` configuration WITHOUT system "root" CAs.
+    bool has_strong_verification(boost::string_ref host) const noexcept;
+
     //! Search against internal fingerprints. Always false if `behavior() != user_certificate_check`.
     bool has_fingerprint(boost::asio::ssl::verify_context &ctx) const;
 

contrib/epee/src/net_ssl.cpp

@@ -278,6 +278,25 @@ bool is_ssl(const unsigned char *data, size_t len)
   return false;
 }
 
+bool ssl_options_t::has_strong_verification(boost::string_ref host) const noexcept
+{
+  // onion and i2p addresses contain information about the server cert
+  // which both authenticates and encrypts
+  if (host.ends_with(".onion") || host.ends_with(".i2p"))
+    return true;
+  switch (verification)
+  {
+    default:
+    case ssl_verification_t::none:
+    case ssl_verification_t::system_ca:
+      return false;
+    case ssl_verification_t::user_certificates:
+    case ssl_verification_t::user_ca:
+      break;
+  }
+  return true;
+}
+
 bool ssl_options_t::has_fingerprint(boost::asio::ssl::verify_context &ctx) const
 {
   // can we check the certificate against a list of fingerprints?

src/wallet/wallet2.cpp

@@ -315,6 +315,7 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   const uint64_t kdf_rounds = command_line::get_arg(vm, opts.kdf_rounds);
   THROW_WALLET_EXCEPTION_IF(kdf_rounds == 0, tools::error::wallet_internal_error, "KDF rounds must not be 0");
 
+  const bool use_proxy = command_line::has_arg(vm, opts.proxy);
   auto daemon_address = command_line::get_arg(vm, opts.daemon_address);
   auto daemon_host = command_line::get_arg(vm, opts.daemon_host);
   auto daemon_port = command_line::get_arg(vm, opts.daemon_port);
@@ -382,22 +383,24 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   if (daemon_address.empty())
     daemon_address = std::string("http://") + daemon_host + ":" + std::to_string(daemon_port);
 
-  boost::asio::ip::tcp::endpoint proxy{};
-  if (command_line::has_arg(vm, opts.proxy))
   {
-    namespace ip = boost::asio::ip;
     const boost::string_ref real_daemon = boost::string_ref{daemon_address}.substr(0, daemon_address.rfind(':'));
 
-    // onion and i2p addresses contain information about the server cert
+    const bool verification_required =
-    // which both authenticates and encrypts
+      ssl_options.support == epee::net_utils::ssl_support_t::e_ssl_support_enabled || use_proxy;
-    const bool unencrypted_proxy =
+
-      !real_daemon.ends_with(".onion") && !real_daemon.ends_with(".i2p") &&
-      daemon_ssl_ca_file.empty() && daemon_ssl_allowed_fingerprints.empty();
     THROW_WALLET_EXCEPTION_IF(
-      unencrypted_proxy,
+      verification_required && !ssl_options.has_strong_verification(real_daemon),
       tools::error::wallet_internal_error,
-      std::string{"Use of --"} + opts.proxy.name + " requires --" + opts.daemon_ssl_ca_certificates.name + " or --" + opts.daemon_ssl_allowed_fingerprints.name + " or use of a .onion/.i2p domain"
+      tools::wallet2::tr("Enabling --") + std::string{use_proxy ? opts.proxy.name : opts.daemon_ssl.name} + tools::wallet2::tr(" requires --") +
+        opts.daemon_ssl_ca_certificates.name + tools::wallet2::tr(" or --") + opts.daemon_ssl_allowed_fingerprints.name + tools::wallet2::tr(" or use of a .onion/.i2p domain")
     );
+  }
+
+  boost::asio::ip::tcp::endpoint proxy{};
+  if (use_proxy)
+  {
+    namespace ip = boost::asio::ip;
 
     const auto proxy_address = command_line::get_arg(vm, opts.proxy);
 

src/wallet/wallet_rpc_server.cpp

@@ -4060,13 +4060,7 @@ namespace tools
       er.message = "Command unavailable in restricted mode.";
       return false;
     }
-    epee::net_utils::ssl_options_t ssl_options = epee::net_utils::ssl_support_t::e_ssl_support_enabled;
+   
-    if (!epee::net_utils::ssl_support_from_string(ssl_options.support, req.ssl_support))
-    {
-      er.code = WALLET_RPC_ERROR_CODE_NO_DAEMON_CONNECTION;
-      er.message = std::string("Invalid ssl support mode");
-      return false;
-    }
     std::vector<std::vector<uint8_t>> ssl_allowed_fingerprints;
     ssl_allowed_fingerprints.reserve(req.ssl_allowed_fingerprints.size());
     for (const std::string &fp: req.ssl_allowed_fingerprints)
@@ -4076,15 +4070,30 @@ namespace tools
       for (auto c: fp)
         v.push_back(c);
     }
+
+    epee::net_utils::ssl_options_t ssl_options = epee::net_utils::ssl_support_t::e_ssl_support_enabled;
     if (req.ssl_allow_any_cert)
       ssl_options.verification = epee::net_utils::ssl_verification_t::none;
     else if (!ssl_allowed_fingerprints.empty() || !req.ssl_ca_file.empty())
       ssl_options = epee::net_utils::ssl_options_t{std::move(ssl_allowed_fingerprints), std::move(req.ssl_ca_file)};
 
+    if (!epee::net_utils::ssl_support_from_string(ssl_options.support, req.ssl_support))
+    {
+      er.code = WALLET_RPC_ERROR_CODE_NO_DAEMON_CONNECTION;
+      er.message = std::string("Invalid ssl support mode");
+      return false;
+    }
+
     ssl_options.auth = epee::net_utils::ssl_authentication_t{
       std::move(req.ssl_private_key_path), std::move(req.ssl_certificate_path)
     };
 
+    if (ssl_options.support == epee::net_utils::ssl_support_t::e_ssl_support_enabled && !ssl_options.has_strong_verification(boost::string_ref{}))
+    {
+      er.code = WALLET_RPC_ERROR_CODE_NO_DAEMON_CONNECTION;
+      er.message = "SSL is enabled but no user certificate or fingerprints were provided";
+    }
+
     if (!m_wallet->set_daemon(req.address, boost::none, req.trusted, std::move(ssl_options)))
     {
       er.code = WALLET_RPC_ERROR_CODE_NO_DAEMON_CONNECTION;