openclonk/src/lib/C4InputValidation.cpp

/*
 * OpenClonk, http://www.openclonk.org
 *
 * Copyright (c) 2007-2008  Sven Eberhardt
 * Copyright (c) 2008  Matthes Bender
 * Copyright (c) 2007-2009, RedWolf Design GmbH, http://www.clonk.de
 *
 * Portions might be copyrighted by other authors who have contributed
 * to OpenClonk.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 * See isc_license.txt for full license and disclaimer.
 *
 * "Clonk" is a registered trademark of Matthes Bender.
 * See clonk_trademark_license.txt for full license.
 */
// user input validation functions

#include "C4Include.h"
#include <Standard.h>
#include <C4InputValidation.h>
#include <C4Log.h>
#include "StdMarkup.h"

#include <cctype>

namespace C4InVal
	{
	bool ValidateString(char *szString, ValidationOption eOption, size_t iMaxSize)
		{
		// validate in a StdStrBuf. Does one alloc and copy :(
		StdStrBuf buf; buf.Copy(szString);
		bool fInvalid = ValidateString(buf, eOption);
		if (fInvalid) SCopy(buf.getData(), szString, iMaxSize);
		return fInvalid;
		}

	bool ValidateString(StdStrBuf &rsString, ValidationOption eOption)
		{
		bool fValid = true;
		// validation depending on option
		// check min length
		if (!rsString.getLength())
			{
			// empty if not allowed?
			if (eOption != VAL_NameAllowEmpty && eOption != VAL_NameExAllowEmpty && eOption != VAL_Comment)
				{
				rsString.Copy("empty");
				fValid = false;
				}
			}
		switch (eOption)
			{
			case VAL_Filename: // regular filenames only
				// absolutely no directory traversal
				if (rsString.ReplaceChar('/', '_')) fValid = false;
				if (rsString.ReplaceChar('\\', '_')) fValid = false;

				// fallthrough to general file name validation
			case VAL_SubPathFilename: // filenames and optional subpath
				// do not traverse upwards in file hierarchy
				if (rsString.Replace("..", "__")) fValid = false;
				if (*rsString.getData() == '/' || *rsString.getData() == '\\') { *rsString.getMData() = '_'; fValid = false; }

				// fallthrough to general file name validation
			case VAL_FullPath:        // full filename paths
				// some characters are prohibited in filenames in general
				if (rsString.ReplaceChar('*', '_')) fValid = false;
				if (rsString.ReplaceChar('?', '_')) fValid = false;
				if (rsString.ReplaceChar('<', '_')) fValid = false;
				if (rsString.ReplaceChar('>', '_')) fValid = false;
				// ';' and '|' is never allowed in filenames, because it would cause problems in many engine internal file lists
				if (rsString.ReplaceChar(';', '_')) fValid = false;
				if (rsString.ReplaceChar('|', '_')) fValid = false;
				// the colon is generally prohibited except at pos 2 (C:\...), because it could lead to creation of (invisible) streams on NTFS
				if (rsString.ReplaceChar(':', '_', 2)) fValid = false;
				if (*rsString.getData() == ':') { *rsString.getMData() = '_'; fValid = false; }
				// validate drive letter
				if (rsString.getLength()>=2 && *rsString.getPtr(1) == ':')
					{
					if (eOption != VAL_FullPath)
						{
						*rsString.getMPtr(1)='_'; fValid = false;
						}
					else if (!isalpha((unsigned char)*rsString.getData()) || (*rsString.getPtr(2)!='\\' && *rsString.getPtr(2)!='/'))
						{
						*rsString.getMData()=*rsString.getMPtr(1)='_'; fValid = false;
						}
					}
				break;

			case VAL_NameNoEmpty:
			case VAL_NameAllowEmpty:
				// no markup
				if (CMarkup::StripMarkup(&rsString)) { fValid = false; }
				// trim spaces
				if (rsString.TrimSpaces()) fValid = false;
				// min length
				if (eOption == VAL_NameNoEmpty) if (!rsString.getLength()) { fValid = false; rsString.Copy("Unknown"); }
				// max length
				if (rsString.getLength() > C4MaxName) { fValid = false; rsString.SetLength(C4MaxName); }
				break;

			case VAL_NameExNoEmpty:
			case VAL_NameExAllowEmpty:
				// trim spaces
				if (rsString.TrimSpaces()) fValid = false;
				// min length
				if (eOption == VAL_NameExNoEmpty) if (!rsString.getLength()) { fValid = false; rsString.Copy("Unknown"); }
				// max length
				if (rsString.getLength() > C4MaxLongName) { fValid = false; rsString.SetLength(C4MaxLongName); }
				break;

			case VAL_IRCName: // nickname for IRC. a-z, A-Z, _^{[]} only; 0-9|- inbetween; max 30 characters
				if (rsString.getLength() > 30) fValid = false;
				if (rsString.getLength() < 2) fValid = false;
				if (!rsString.ValidateChars("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_^{[]}", "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_^{[]}0123456789|-")) { fValid = false; rsString.Copy("Guest"); }
				if (SEqualNoCase(rsString.getData(), "NickServ")
				 || SEqualNoCase(rsString.getData(), "ChanServ")
				 || SEqualNoCase(rsString.getData(), "MemoServ")
				 || SEqualNoCase(rsString.getData(), "OperServ")
				 || SEqualNoCase(rsString.getData(), "HelpServ")) fValid = false;
				if (!fValid) rsString.Copy("Guest");
				break;

			case VAL_IRCPass: // password for IRC; max 31 characters
				// max length; no spaces
				if (rsString.getLength() > 31) { fValid = false; rsString.SetLength(31); }
				if (rsString.getLength() < 2) { fValid = false; rsString.Copy("secret"); }
				if (rsString.ReplaceChar(' ', '_')) fValid = false;
				break;

			case VAL_IRCChannel: // IRC channel name
				if (rsString.getLength() > 32) { fValid = false; rsString.SetLength(32); }
				else if (rsString.getLength() < 2) { fValid = false; rsString.Copy("#clonken"); }
				else if (*rsString.getData() != '#' && *rsString.getData() != '+') { fValid = false; *rsString.getMData() = '#'; }
				if (rsString.ReplaceChar(' ', '_')) fValid = false;
				break;

			case VAL_Comment: // comment - just limit length
				if (rsString.getLength() > C4MaxComment) { fValid = false; rsString.SetLength(C4MaxComment); }
				break;

			default:
				assert(!"not yet implemented");
			}
		// issue warning for invalid adjustments
		if (!fValid)
			{
			const char *szOption = "unknown";
			switch (eOption)
				{
				case VAL_Filename:         szOption = "filename";         break;
				case VAL_SubPathFilename:  szOption = "(sub-)filename";   break;
				case VAL_FullPath:         szOption = "free filename";    break;
				case VAL_NameNoEmpty:      szOption = "strict name";      break;
				case VAL_NameExNoEmpty:    szOption = "name";             break;
				case VAL_NameAllowEmpty:   szOption = "strict name*";     break;
				case VAL_NameExAllowEmpty: szOption = "name*";            break;
				case VAL_IRCName:          szOption = "IRC nick";         break;
				case VAL_IRCPass:          szOption = "IRC password";     break;
				case VAL_IRCChannel:       szOption = "IRC channel";      break;
				case VAL_Comment:          szOption = "Comment";          break;
				}
			//LogF("WARNING: Adjusted invalid user input for \"%s\" to \"%s\"", szOption, rsString.getData());
			}
		return !fValid;
		}

	bool ValidateInt(int32_t &riVal, int32_t iMinVal, int32_t iMaxVal)
		{
		if (riVal < iMinVal) { riVal = iMinVal; return false; }
		else if (riVal > iMaxVal) { riVal = iMaxVal; return false; }
		else return true;
		}
	};