HPCC-32999 Sanitize user provided password to ZAP file

- Single-quote the entire password to preserve all characters but prevent
  interpretation as metacharacters.
- Replace any single quote in the original string with a sequence of characters
  that breaks the single-quoted password into three parts
    (1) a single-quoted prefix
    (2) a double-quoted single quote and
    (3) a single-quoted suffix
- The shell quote-removal deletes double-quotes around any single quote at the
  same time that it de-quotes the single-quoted prefix and suffix, leaving any
  single quote inside the password string that is tokenized as a single
  argument.

This will require a different approach for Windows targets as a future task.

Signed-off-by: Terrence Asselin <[email protected]>

esp/services/ws_workunits/ws_workunitsHelpers.cpp

@@ -4386,7 +4386,11 @@ void CWsWuFileHelper::zipZAPFiles(const char* parentFolder, const char* zapFiles
     else
         zipCommand.setf("cd %s\nzip -r", parentFolder);
     if (!isEmptyString(passwordReq))
-        zipCommand.append(" --password ").append(passwordReq);
+    {
+        StringBuffer sanitizedPassword;
+        sanitizeCommandArg(passwordReq, sanitizedPassword);
+        zipCommand.append(" --password ").append(sanitizedPassword);
+    }
     zipCommand.append(" ").append(zipFileNameWithFullPath).append(" ").append(zapFiles);
     int zipRet = system(zipCommand);
     if (zipRet != 0)

system/jlib/jstring.cpp

@@ -2902,3 +2902,32 @@ const char * stristr (const char *haystack, const char *needle)
 
     return nullptr;
 }
+
+/**
+ * For preventing command injection, sanitize the argument to be passed to the system command.
+ * - Quote the entire argument with single quotes to prevent interpretation of shell metacharacters.
+ * - Since a single-quoted string can't contain single quotes, even escaped, replace each single
+ *   quote in the argument with the sequence '"'"' . That closes the single quoted string, appends
+ *   a literal single quote, and reopens the single quoted string
+ */
+StringBuffer& sanitizeCommandArg(const char* arg, StringBuffer& sanitized)
+{
+#if defined(__linux__) || defined(__APPLE__)
+    if (!isEmptyString(arg))
+    {
+        size_t len = strlen(arg);
+        sanitized.append('\'');
+        for (size_t i = 0; i < len; i++)
+        {
+            if (arg[i] == '\'')
+                sanitized.append(R"('"'"')");
+            else
+                sanitized.append(arg[i]);
+        }
+        sanitized.append('\'');
+    }
+#else
+    sanitized.append(arg);
+#endif
+    return sanitized;
+}

system/jlib/jstring.hpp

@@ -641,4 +641,7 @@ extern jlib_decl void processOptionString(const char * options, optionCallback c
 
 extern jlib_decl const char * stristr(const char *haystack, const char *needle);
 
+// For preventing command injection, sanitize the argument to be passed to the system command
+extern jlib_decl StringBuffer& sanitizeCommandArg(const char* arg, StringBuffer& sanitized);
+
 #endif