Wallet: Sanitise -wallet parameter

Author: luke-jr

src/utilstrencodings.cpp

@@ -19,7 +19,8 @@ static const string CHARS_ALPHA_NUM = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNO
 static const string SAFE_CHARS[] =
 {
     CHARS_ALPHA_NUM + " .,;-_/:?@()", // SAFE_CHARS_DEFAULT
-    CHARS_ALPHA_NUM + " .,;-_?@" // SAFE_CHARS_UA_COMMENT
+    CHARS_ALPHA_NUM + " .,;-_?@", // SAFE_CHARS_UA_COMMENT
+    CHARS_ALPHA_NUM + ".-_", // SAFE_CHARS_FILENAME
 };
 
 string SanitizeString(const string& str, int rule)

src/utilstrencodings.h

@@ -26,7 +26,8 @@
 enum SafeChars
 {
     SAFE_CHARS_DEFAULT, //!< The full set of allowed chars
-    SAFE_CHARS_UA_COMMENT //!< BIP-0014 subset
+    SAFE_CHARS_UA_COMMENT, //!< BIP-0014 subset
+    SAFE_CHARS_FILENAME, //!< Chars allowed in filenames
 };
 
 /**

src/wallet/wallet.cpp

@@ -3765,6 +3765,12 @@ bool CWallet::InitLoadWallet()
 
     std::string walletFile = GetArg("-wallet", DEFAULT_WALLET_DAT);
 
+    if (walletFile.find_first_of("/\\") != std::string::npos) {
+        return InitError(_("-wallet parameter must only specify a filename (not a path)"));
+    } else if (SanitizeString(walletFile, SAFE_CHARS_FILENAME) != walletFile) {
+        return InitError(_("Invalid characters in -wallet filename"));
+    }
+
     CWallet * const pwallet = CreateWalletFromFile(walletFile);
     if (!pwallet) {
         return false;