security enhancements and small formatting changes

- wipe crypto password on all crypto folder unlock return paths
- wipe passwords on logout/unlink
- *pwd reference setup only after online check succeeds

pclsync/putil.h

@@ -1,6 +1,10 @@
 #ifndef __PUTIL_H
 #define __PUTIL_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #include <stddef.h>
 
 #define NTO_STR(s) TO_STR(s)
@@ -9,4 +13,8 @@
 
 void putil_wipe(void *mem, size_t sz);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif

pclsync_lib.cpp

@@ -43,6 +43,7 @@
 #include "pshm.h"
 #include "pdevice.h"
 #include "pcommands.h"
+#include "putil.h"
 
 #include "pclsync_lib.h"
 
@@ -70,6 +71,18 @@ const std::string &clib::pclsync_lib::get_crypto_pass() {
   return crypto_pass_;
 };
 
+void clib::pclsync_lib::wipe_crypto_pass() {
+  this->wipe(crypto_pass_);
+}
+
+void clib::pclsync_lib::wipe_password() {
+  this->wipe(password_);
+}
+
+void clib::pclsync_lib::wipe_tfa_code() {
+  this->wipe(tfa_code_);
+}
+
 const std::string &clib::pclsync_lib::get_mount() { return mount_; }
 
 void clib::pclsync_lib::set_trusted_device(bool arg) {
@@ -201,21 +214,22 @@ void event_handler(psync_eventtype_t event, psync_eventdata_t eventdata) {
 }
 
 static int lib_setup_cripto() {
-  const char *pwd = clib::pclsync_lib::get_lib().get_crypto_pass().c_str();
-
   if(pstatus_get(PSTATUS_TYPE_ONLINE) == PSTATUS_ONLINE_OFFLINE) {
     std::cout << "Cannot unlock crypto folder, pcloudcc is offline" << std::endl;
     return PSYNC_CRYPTO_CANT_CONNECT;
   }
 
+  const char *pwd = clib::pclsync_lib::get_lib().get_crypto_pass().c_str();
   if(!pcryptofolder_issetup()) {
     std::cout << "crypto is not setup, setting it up now..." << std::endl;
     if(int ret = pcryptofolder_setup(pwd, "no hint") != PSYNC_CRYPTO_SETUP_SUCCESS) {
       std::cout << "crypto setup failed, error code was " << ret << std::endl;
+      clib::pclsync_lib::get_lib().wipe_crypto_pass();
       return ret;
     }
     if(int ret = pcryptofolder_mkdir(0, "Crypto", NULL, NULL) != PSYNC_CRYPTO_SUCCESS) {
       std::cout << "failed to create crypto directory, error code was" << ret << std::endl;
+      clib::pclsync_lib::get_lib().wipe_crypto_pass();
       return ret;
     }
     std::cout << "crypto folder was setup using the provided password, "
@@ -225,9 +239,11 @@ static int lib_setup_cripto() {
 
   if(int ret = pcryptofolder_unlock(pwd) != PSYNC_CRYPTO_START_SUCCESS) {
     std::cout << "Failed to unlock crypto folder: error code was " << ret << std::endl;
+    clib::pclsync_lib::get_lib().wipe_crypto_pass();
     return ret;
   }
 
+  clib::pclsync_lib::get_lib().wipe_crypto_pass();
   clib::pclsync_lib::get_lib().crypto_on_ = true;
   return 0;
 }
@@ -470,22 +486,33 @@ int clib::pclsync_lib::init() {
 }
 
 int clib::pclsync_lib::login(const char *user, const char *pass, int save) {
-  set_username(user);
-  set_password(pass);
-  set_savepass(bool(save));
+  username_ = user;
+  password_ = pass;
+  save_pass_ = save;
   psync_set_user_pass(user, pass, save);
   return 0;
 }
 
 int clib::pclsync_lib::logout() {
-  set_password("");
+  wipe_password();
   psync_logout();
   return 0;
 }
 
 int clib::pclsync_lib::unlink() {
   set_username("");
-  set_password("");
+  wipe_password();
   psync_unlink();
   return 0;
 }
+
+void clib::pclsync_lib::wipe(std::string& s) {
+    if (s.empty()) {
+      return;
+    }
+
+    void* mem = &s[0];
+    size_t sz = s.size();
+    putil_wipe(mem, sz);
+    s.clear();
+}

pclsync_lib.h

@@ -77,6 +77,12 @@ public:
   void set_daemon(bool p);
   void set_status_callback(status_callback_t p);
 
+  // FIXME: not ideal, better if programmer does not have to remember to do
+  // this, but good enough for now...
+  void wipe_password();
+  void wipe_crypto_pass();
+  void wipe_tfa_code();
+
   // Singleton
   static pclsync_lib &get_lib();
 
@@ -103,9 +109,9 @@ public:
 
 private:
   std::string username_;
-  std::string password_;
-  std::string tfa_code_;
-  std::string crypto_pass_;
+  std::string password_;    // SENSITIVE, use wipe function
+  std::string tfa_code_;    // SENSITIVE, use wipe function
+  std::string crypto_pass_; // SENSITIVE, use wipe function
   std::string mount_;
 
 
@@ -113,6 +119,7 @@ private:
   bool daemon_;
 
   void do_get_pass_from_console(std::string &password);
+  void wipe(std::string& str);
 };
 } // namespace clibrary
 } // namespace console_client