Enabled HTTP auth support for monero-wallet-rpc

5 files changed, 205 insertions, 17 deletions

diff --git a/src/common/boost_serialization_helper.h b/src/common/boost_serialization_helper.h
index c640a1705..bf0023471 100644
--- a/src/common/boost_serialization_helper.h
+++ b/src/common/boost_serialization_helper.h
@@ -53,8 +53,8 @@ namespace tools
       return false;
     }
 
-    FILE* data_file_file = _fdopen(data_file_descriptor, "wb");
-    if (0 == data_file_file)
+    const std::unique_ptr<FILE, tools::close_file> data_file_file{_fdopen(data_file_descriptor, "wb")};
+    if (nullptr == data_file_file)
     {
       // Call CloseHandle is not necessary
       _close(data_file_descriptor);
@@ -62,11 +62,10 @@ namespace tools
     }
 
     // HACK: undocumented constructor, this code may not compile
-    std::ofstream data_file(data_file_file);
+    std::ofstream data_file(data_file_file.get());
     if (data_file.fail())
     {
       // Call CloseHandle and _close are not necessary
-      fclose(data_file_file);
       return false;
     }
 #else
@@ -85,7 +84,6 @@ namespace tools
 #if defined(_MSC_VER)
     // To make sure the file is fully stored on disk
     ::FlushFileBuffers(data_file_handle);
-    fclose(data_file_file);
 #endif
 
     return true;
diff --git a/src/common/util.cpp b/src/common/util.cpp
index a53a9be52..6dec6af2a 100644
--- a/src/common/util.cpp
+++ b/src/common/util.cpp
@@ -50,6 +50,92 @@ namespace tools
 {
   std::function<void(int)> signal_handler::m_handler;
 
+  std::unique_ptr<std::FILE, tools::close_file> create_private_file(const std::string& name)
+  {
+#ifdef WIN32
+    struct close_handle
+    {
+      void operator()(HANDLE handle) const noexcept
+      {
+        CloseHandle(handle);
+      }
+    };
+
+    std::unique_ptr<void, close_handle> process = nullptr;
+    {
+      HANDLE temp{};
+      const bool fail = OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, std::addressof(temp)) == 0;
+      process.reset(temp);
+      if (fail)
+        return nullptr;
+    }
+
+    DWORD sid_size = 0;
+    GetTokenInformation(process.get(), TokenOwner, nullptr, 0, std::addressof(sid_size));
+    if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+      return nullptr;
+
+    std::unique_ptr<char[]> sid{new char[sid_size]};
+    if (!GetTokenInformation(process.get(), TokenOwner, sid.get(), sid_size, std::addressof(sid_size)))
+      return nullptr;
+
+    const PSID psid = reinterpret_cast<const PTOKEN_OWNER>(sid.get())->Owner;
+    const DWORD daclSize =
+      sizeof(ACL) + sizeof(ACCESS_ALLOWED_ACE) + GetLengthSid(psid) - sizeof(DWORD);
+
+    const std::unique_ptr<char[]> dacl{new char[daclSize]};
+    if (!InitializeAcl(reinterpret_cast<PACL>(dacl.get()), daclSize, ACL_REVISION))
+      return nullptr;
+
+    if (!AddAccessAllowedAce(reinterpret_cast<PACL>(dacl.get()), ACL_REVISION, (READ_CONTROL | FILE_GENERIC_READ | DELETE), psid))
+      return nullptr;
+
+    SECURITY_DESCRIPTOR descriptor{};
+    if (!InitializeSecurityDescriptor(std::addressof(descriptor), SECURITY_DESCRIPTOR_REVISION))
+      return nullptr;
+
+    if (!SetSecurityDescriptorDacl(std::addressof(descriptor), true, reinterpret_cast<PACL>(dacl.get()), false))
+      return nullptr;
+
+    SECURITY_ATTRIBUTES attributes{sizeof(SECURITY_ATTRIBUTES), std::addressof(descriptor), false};
+    std::unique_ptr<void, close_handle> file{
+      CreateFile(
+        name.c_str(),
+        GENERIC_WRITE, FILE_SHARE_READ,
+        std::addressof(attributes),
+        CREATE_NEW, FILE_ATTRIBUTE_TEMPORARY,
+        nullptr
+      )
+    };
+    if (file)
+    {
+      const int fd = _open_osfhandle(reinterpret_cast<intptr_t>(file.get()), 0);
+      if (0 <= fd)
+      {
+        file.release();
+        std::FILE* real_file = _fdopen(fd, "w");
+        if (!real_file)
+        {
+          _close(fd);
+        }
+        return {real_file, tools::close_file{}};
+      }
+    }
+#else
+    const int fd = open(name.c_str(), (O_RDWR | O_EXCL | O_CREAT), S_IRUSR);
+    if (0 <= fd)
+    {
+      std::FILE* file = fdopen(fd, "w");
+      if (!file)
+      {
+        close(fd);
+      }
+      return {file, tools::close_file{}};
+    }
+#endif
+    return nullptr;
+  }
+
 #ifdef WIN32
   std::string get_windows_version_display_string()
   {
diff --git a/src/common/util.h b/src/common/util.h
index 4fcf66b8f..3bb9a053e 100644
--- a/src/common/util.h
+++ b/src/common/util.h
@@ -30,13 +30,15 @@
 
 #pragma once 
 
-#include <mutex>
-#include <system_error>
-#include <boost/filesystem.hpp>
+#include <boost/thread/locks.hpp>
+#include <boost/thread/mutex.hpp>
+#include <csignal>
+#include <cstdio>
+#include <functional>
+#include <memory>
+#include <string>
 
-#include "crypto/crypto.h"
 #include "crypto/hash.h"
-#include "misc_language.h"
 #include "p2p/p2p_protocol_defs.h"
 
 /*! \brief Various Tools
@@ -46,6 +48,21 @@
  */
 namespace tools
 {
+  //! Functional class for closing C file handles.
+  struct close_file
+  {
+    void operator()(std::FILE* handle) const noexcept
+    {
+      if (handle)
+      {
+        std::fclose(handle);
+      }
+    }
+  };
+
+  //! \return File only readable by owner. nullptr if `filename` exists.
+  std::unique_ptr<std::FILE, close_file> create_private_file(const std::string& filename);
+
   /*! \brief Returns the default data directory.
    *
    * \details Windows < Vista: C:\\Documents and Settings\\Username\\Application Data\\CRYPTONOTE_NAME
diff --git a/src/wallet/wallet_rpc_server.cpp b/src/wallet/wallet_rpc_server.cpp
index 7c08bbe4b..c34ce4cf2 100644
--- a/src/wallet/wallet_rpc_server.cpp
+++ b/src/wallet/wallet_rpc_server.cpp
@@ -28,6 +28,7 @@
 // 
 // Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
 #include <boost/asio/ip/address.hpp>
+#include <boost/filesystem/operations.hpp>
 #include <cstdint>
 #include "include_base_utils.h"
 using namespace epee;
@@ -36,10 +37,12 @@ using namespace epee;
 #include "wallet/wallet_args.h"
 #include "common/command_line.h"
 #include "common/i18n.h"
+#include "common/util.h"
 #include "cryptonote_core/cryptonote_format_utils.h"
 #include "cryptonote_core/account.h"
 #include "wallet_rpc_server_commands_defs.h"
 #include "misc_language.h"
+#include "string_coding.h"
 #include "string_tools.h"
 #include "crypto/hash.h"
 
@@ -47,9 +50,11 @@ namespace
 {
   const command_line::arg_descriptor<std::string, true> arg_rpc_bind_port = {"rpc-bind-port", "Sets bind port for server"};
   const command_line::arg_descriptor<std::string> arg_rpc_bind_ip = {"rpc-bind-ip", "Specify ip to bind rpc server", "127.0.0.1"};
-  const command_line::arg_descriptor<std::string> arg_user_agent = {"user-agent", "Restrict RPC to clients using this user agent", ""};
-
+  const command_line::arg_descriptor<std::string> arg_rpc_login = {"rpc-login", "Specify username[:password] required for RPC connection"};
+  const command_line::arg_descriptor<bool> arg_disable_rpc_login = {"disable-rpc-login", "Disable HTTP authentication for RPC"};
   const command_line::arg_descriptor<bool> arg_confirm_external_bind = {"confirm-external-bind", "Confirm rcp-bind-ip value is NOT a loopback (local) IP"};
+
+  constexpr const char default_rpc_username[] = "monero";
 }
 
 namespace tools
@@ -60,9 +65,19 @@ namespace tools
   }
 
   //------------------------------------------------------------------------------------------------------------------------------
-  wallet_rpc_server::wallet_rpc_server(wallet2& w):m_wallet(w)
+  wallet_rpc_server::wallet_rpc_server(wallet2& w):m_wallet(w), rpc_login_filename(), m_stop(false)
   {}
   //------------------------------------------------------------------------------------------------------------------------------
+  wallet_rpc_server::~wallet_rpc_server()
+  {
+    try
+    {
+      boost::system::error_code ec{};
+      boost::filesystem::remove(rpc_login_filename, ec);
+    }
+    catch (...) {}
+  }
+  //------------------------------------------------------------------------------------------------------------------------------
   bool wallet_rpc_server::run()
   {
     m_stop = false;
@@ -110,11 +125,79 @@ namespace tools
       }
     }
 
+    epee::net_utils::http::http_auth::login login{};
+
+    const bool disable_auth = command_line::get_arg(vm, arg_disable_rpc_login);
+    const std::string user_pass = command_line::get_arg(vm, arg_rpc_login);
+    const std::string bind_port = command_line::get_arg(vm, arg_rpc_bind_port);
+
+    if (disable_auth)
+    {
+      if (!user_pass.empty())
+      {
+        LOG_ERROR(tr("Cannot specify --") << arg_disable_rpc_login.name << tr(" and --") << arg_rpc_login.name);
+        return false;
+      }
+    }
+    else // auth enabled
+    {
+      if (user_pass.empty())
+      {
+        login.username = default_rpc_username;
+
+        std::array<std::uint8_t, 16> rand_128bit{{}};
+        crypto::rand(rand_128bit.size(), rand_128bit.data());
+        login.password = string_encoding::base64_encode(rand_128bit.data(), rand_128bit.size());
+      }
+      else // user password
+      {
+        const auto loc = user_pass.find(':');
+        login.username = user_pass.substr(0, loc);
+        if (loc != std::string::npos)
+        {
+          login.password = user_pass.substr(loc + 1);
+        }
+        else
+        {
+          tools::password_container pwd(true);
+          pwd.read_password("RPC password");
+          login.password = pwd.password();
+        }
+
+        if (login.username.empty() || login.password.empty())
+        {
+          LOG_ERROR(tr("Blank username or password not permitted for RPC authenticaion"));
+          return false;
+        }
+      }
+
+      assert(!login.username.empty());
+      assert(!login.password.empty());
+
+      std::string temp = "monero-wallet-rpc." + bind_port + ".login";
+      const auto cookie = tools::create_private_file(temp);
+      if (!cookie)
+      {
+        LOG_ERROR(tr("Failed to create file ") << temp << tr(". Check permissions or remove file"));
+        return false;
+      }
+      rpc_login_filename.swap(temp); // nothrow guarantee destructor cleanup
+      temp = rpc_login_filename;
+      std::fputs(login.username.c_str(), cookie.get());
+      std::fputc(':', cookie.get());
+      std::fputs(login.password.c_str(), cookie.get());
+      std::fflush(cookie.get());
+      if (std::ferror(cookie.get()))
+      {
+        LOG_ERROR(tr("Error writing to file ") << temp);
+        return false;
+      }
+      LOG_PRINT_L0(tr("RPC username/password is stored in file ") << temp);
+    } // end auth enabled
+
     m_net_server.set_threads_prefix("RPC");
     return epee::http_server_impl_base<wallet_rpc_server, connection_context>::init(
-      command_line::get_arg(vm, arg_rpc_bind_port),
-      std::move(bind_ip),
-      command_line::get_arg(vm, arg_user_agent)
+      std::move(bind_port), std::move(bind_ip), std::string{}, boost::make_optional(!disable_auth, std::move(login))
     );
   }
   //------------------------------------------------------------------------------------------------------------------------------
@@ -1132,7 +1215,8 @@ int main(int argc, char** argv) {
   tools::wallet2::init_options(desc_params);
   command_line::add_arg(desc_params, arg_rpc_bind_ip);
   command_line::add_arg(desc_params, arg_rpc_bind_port);
-  command_line::add_arg(desc_params, arg_user_agent);
+  command_line::add_arg(desc_params, arg_rpc_login);
+  command_line::add_arg(desc_params, arg_disable_rpc_login);
   command_line::add_arg(desc_params, arg_confirm_external_bind);
   command_line::add_arg(desc_params, arg_wallet_file);
   command_line::add_arg(desc_params, arg_from_json);
diff --git a/src/wallet/wallet_rpc_server.h b/src/wallet/wallet_rpc_server.h
index 96ca1af04..8701d38cd 100644
--- a/src/wallet/wallet_rpc_server.h
+++ b/src/wallet/wallet_rpc_server.h
@@ -32,6 +32,7 @@
 
 #include <boost/program_options/options_description.hpp>
 #include <boost/program_options/variables_map.hpp>
+#include <string>
 #include "net/http_server_impl_base.h"
 #include "wallet_rpc_server_commands_defs.h"
 #include "wallet2.h"
@@ -48,6 +49,7 @@ namespace tools
     static const char* tr(const char* str);
 
     wallet_rpc_server(wallet2& cr);
+    ~wallet_rpc_server();
 
     bool init(const boost::program_options::variables_map& vm);
     bool run();
@@ -118,6 +120,7 @@ namespace tools
       bool on_query_key(const wallet_rpc::COMMAND_RPC_QUERY_KEY::request& req, wallet_rpc::COMMAND_RPC_QUERY_KEY::response& res, epee::json_rpc::error& er);
 
       wallet2& m_wallet;
+      std::string rpc_login_filename;
       std::atomic<bool> m_stop;
   };
 }