Changeset - r28506:4fd07c3f848d
[Not reviewed]
master
0 4 0
Loïc Guilloux - 3 months ago 2024-01-18 17:06:30
glx22@users.noreply.github.com
Fix: [Script] Improve ScriptText validation (#11721)

The validation is now done in two steps:
- First we get the list of parameters in the same order they used to be in encoded string
- Then we validate the parameter types like FormatString would use them while encoding the string
4 files changed with 87 insertions and 60 deletions:
0 comments (0 inline, 0 general)
src/game/game_text.cpp
Show inline comments
 
@@ -268,9 +268,15 @@ static void ExtractStringParams(const St
 
			StringParams &param = params.emplace_back();
 
			ParsedCommandStruct pcs = ExtractCommandString(ls->english.c_str(), false);
 

	
 
			for (const CmdStruct *cs : pcs.consuming_commands) {
 
				if (cs == nullptr) break;
 
				param.emplace_back(GetParamType(cs), cs->consumes);
 
			for (auto it = pcs.consuming_commands.begin(); it != pcs.consuming_commands.end(); it++) {
 
				if (*it == nullptr) {
 
					/* Skip empty param unless a non empty param exist after it. */
 
					if (std::all_of(it, pcs.consuming_commands.end(), [](auto cs) { return cs == nullptr; })) break;
 
					param.emplace_back(StringParam::UNUSED, 1, nullptr);
 
					continue;
 
				}
 
				const CmdStruct *cs = *it;
 
				param.emplace_back(GetParamType(cs), cs->consumes, cs->cmd);
 
			}
 
		}
 
	}
src/game/game_text.hpp
Show inline comments
 
@@ -12,6 +12,7 @@
 

	
 
struct StringParam {
 
	enum ParamType {
 
		UNUSED,
 
		RAW_STRING,
 
		STRING,
 
		OTHER
 
@@ -19,8 +20,9 @@ struct StringParam {
 

	
 
	ParamType type;
 
	uint8_t consumes;
 
	const char *cmd;
 

	
 
	StringParam(ParamType type, uint8_t consumes) : type(type), consumes(consumes) {}
 
	StringParam(ParamType type, uint8_t consumes, const char *cmd) : type(type), consumes(consumes), cmd(cmd) {}
 
};
 
using StringParams = std::vector<StringParam>;
 
using StringParamsList = std::vector<StringParams>;
src/script/api/script_text.cpp
Show inline comments
 
@@ -160,17 +160,28 @@ SQInteger ScriptText::_set(HSQUIRRELVM v
 

	
 
std::string ScriptText::GetEncodedText()
 
{
 
	static StringIDList seen_ids;
 
	StringIDList seen_ids;
 
	ParamList params;
 
	int param_count = 0;
 
	seen_ids.clear();
 
	std::string result;
 
	auto output = std::back_inserter(result);
 
	this->_GetEncodedText(output, param_count, seen_ids);
 
	this->_FillParamList(params);
 
	this->_GetEncodedText(output, param_count, seen_ids, params);
 
	if (param_count > SCRIPT_TEXT_MAX_PARAMETERS) throw Script_FatalError(fmt::format("{}: Too many parameters", GetGameStringName(this->string)));
 
	return result;
 
}
 

	
 
void ScriptText::_GetEncodedText(std::back_insert_iterator<std::string> &output, int &param_count, StringIDList &seen_ids)
 
void ScriptText::_FillParamList(ParamList &params)
 
{
 
	for (int i = 0; i < this->paramc; i++) {
 
		Param *p = &this->param[i];
 
		params.emplace_back(this->string, i, p);
 
		if (!std::holds_alternative<ScriptTextRef>(*p)) continue;
 
		std::get<ScriptTextRef>(*p)->_FillParamList(params);
 
	}
 
}
 

	
 
void ScriptText::_GetEncodedText(std::back_insert_iterator<std::string> &output, int &param_count, StringIDList &seen_ids, ParamSpan args)
 
{
 
	const std::string &name = GetGameStringName(this->string);
 

	
 
@@ -181,63 +192,51 @@ void ScriptText::_GetEncodedText(std::ba
 
	fmt::format_to(output, "{:X}", this->string);
 

	
 
	const StringParams &params = GetGameStringParams(this->string);
 
	int cur_idx = 0;
 
	int prev_string = -1;
 
	int prev_idx = -1;
 
	int prev_count = -1;
 

	
 
	size_t idx = 0;
 
	auto get_next_arg = [&]() {
 
		if (idx >= args.size()) throw Script_FatalError(fmt::format("{}({}): Not enough parameters", name, param_count + 1));
 
		ParamCheck &pc = args[idx++];
 
		if (pc.owner != this->string) ScriptLog::Warning(fmt::format("{}({}): Consumes {}({})", name, param_count + 1, GetGameStringName(pc.owner), pc.idx + 1));
 
		return pc.param;
 
	};
 
	auto skip_args = [&](size_t nb) { idx += nb; };
 

	
 
	for (const StringParam &cur_param : params) {
 
		if (cur_idx >= this->paramc) throw Script_FatalError(fmt::format("{}: Not enough parameters", name));
 
		switch (cur_param.type) {
 
			case StringParam::UNUSED:
 
				skip_args(cur_param.consumes);
 
				break;
 

	
 
		if (prev_string != -1) {
 
			/* The previous substring added more parameters than expected, means we will consume them but can't properly validate them. */
 
			for (int i = 0; i < cur_param.consumes; i++) {
 
				if (prev_idx < prev_count) {
 
					ScriptLog::Warning(fmt::format("{}: Parameter {} uses parameter {} from substring {} and cannot be validated", name, param_count + i, prev_idx++, prev_string));
 
				} else {
 
					/* No more extra parameters, assume SQInteger are expected. */
 
					if (cur_idx >= this->paramc) throw Script_FatalError(fmt::format("{}: Not enough parameters", name));
 
					if (!std::holds_alternative<SQInteger>(this->param[cur_idx])) throw Script_FatalError(fmt::format("{}: Parameter {} expects an integer", name, param_count + i));
 
					fmt::format_to(output, ":{:X}", std::get<SQInteger>(this->param[cur_idx++]));
 
				}
 
			case StringParam::RAW_STRING: {
 
				Param *p = get_next_arg();
 
				if (!std::holds_alternative<std::string>(*p)) throw Script_FatalError(fmt::format("{}({}): {{{}}} expects a raw string", name, param_count + 1, cur_param.cmd));
 
				fmt::format_to(output, ":\"{}\"", std::get<std::string>(*p));
 
				break;
 
			}
 
			if (prev_idx == prev_count) {
 
				/* Re-enable validation. */
 
				prev_string = -1;
 
			}
 
		} else {
 
			switch (cur_param.type) {
 
				case StringParam::RAW_STRING:
 
					if (!std::holds_alternative<std::string>(this->param[cur_idx])) throw Script_FatalError(fmt::format("{}: Parameter {} expects a raw string", name, param_count));
 
					fmt::format_to(output, ":\"{}\"", std::get<std::string>(this->param[cur_idx++]));
 
					break;
 

	
 
				case StringParam::STRING: {
 
					if (!std::holds_alternative<ScriptTextRef>(this->param[cur_idx])) throw Script_FatalError(fmt::format("{}: Parameter {} expects a substring", name, param_count));
 
					int count = 0;
 
					fmt::format_to(output, ":");
 
					std::get<ScriptTextRef>(this->param[cur_idx++])->_GetEncodedText(output, count, seen_ids);
 
					if (++count != cur_param.consumes) {
 
						ScriptLog::Error(fmt::format("{}: Parameter {} substring consumes {}, but expected {} to be consumed", name, param_count, count - 1, cur_param.consumes - 1));
 
						/* Fill missing params if needed. */
 
						for (int i = count; i < cur_param.consumes; i++) fmt::format_to(output, ":0");
 
						/* Disable validation for the extra params if any. */
 
						if (count > cur_param.consumes) {
 
							prev_string = param_count;
 
							prev_idx = cur_param.consumes - 1;
 
							prev_count = count - 1;
 
						}
 
					}
 
					break;
 
			case StringParam::STRING: {
 
				Param *p = get_next_arg();
 
				if (!std::holds_alternative<ScriptTextRef>(*p)) throw Script_FatalError(fmt::format("{}({}): {{{}}} expects a GSText", name, param_count + 1, cur_param.cmd));
 
				int count = 0;
 
				fmt::format_to(output, ":");
 
				ScriptTextRef &ref = std::get<ScriptTextRef>(*p);
 
				ref->_GetEncodedText(output, count, seen_ids, args.subspan(idx));
 
				if (++count != cur_param.consumes) {
 
					ScriptLog::Error(fmt::format("{}({}): {{{}}} expects {} to be consumed, but {} consumes {}", name, param_count + 1, cur_param.cmd, cur_param.consumes - 1, GetGameStringName(ref->string), count - 1));
 
					/* Fill missing params if needed. */
 
					for (int i = count; i < cur_param.consumes; i++) fmt::format_to(output, ":0");
 
				}
 
				skip_args(cur_param.consumes - 1);
 
				break;
 
			}
 

	
 
				default:
 
					if (cur_idx + cur_param.consumes > this->paramc) throw Script_FatalError(fmt::format("{}: Not enough parameters", name));
 
					for (int i = 0; i < cur_param.consumes; i++) {
 
						if (!std::holds_alternative<SQInteger>(this->param[cur_idx])) throw Script_FatalError(fmt::format("{}: Parameter {} expects an integer", name, param_count + i));
 
						fmt::format_to(output, ":{:X}", std::get<SQInteger>(this->param[cur_idx++]));
 
					}
 
			}
 
			default:
 
				for (int i = 0; i < cur_param.consumes; i++) {
 
					Param *p = get_next_arg();
 
					if (!std::holds_alternative<SQInteger>(*p)) throw Script_FatalError(fmt::format("{}({}): {{{}}} expects an integer", name, param_count + i + 1, cur_param.cmd));
 
					fmt::format_to(output, ":{:X}", std::get<SQInteger>(*p));
 
				}
 
		}
 

	
 
		param_count += cur_param.consumes;
src/script/api/script_text.hpp
Show inline comments
 
@@ -130,19 +130,39 @@ public:
 
private:
 
	using ScriptTextRef = ScriptObjectRef<ScriptText>;
 
	using StringIDList = std::vector<StringID>;
 
	using Param = std::variant<SQInteger, std::string, ScriptTextRef>;
 

	
 
	struct ParamCheck {
 
		StringID owner;
 
		int idx;
 
		Param *param;
 

	
 
		ParamCheck(StringID owner, int idx, Param *param) : owner(owner), idx(idx), param(param) {}
 
	};
 

	
 
	using ParamList = std::vector<ParamCheck>;
 
	using ParamSpan = std::span<ParamCheck>;
 

	
 
	StringID string;
 
	std::variant<SQInteger, std::string, ScriptTextRef> param[SCRIPT_TEXT_MAX_PARAMETERS];
 
	Param param[SCRIPT_TEXT_MAX_PARAMETERS];
 
	int paramc;
 

	
 
	/**
 
	 * Internal function to recursively fill a list of parameters.
 
	 * The parameters are added as _GetEncodedText used to encode them
 
	 *  before the addition of parameter validation.
 
	 * @param params The list of parameters to fill.
 
	 */
 
	void _FillParamList(ParamList &params);
 

	
 
	/**
 
	 * Internal function for recursive calling this function over multiple
 
	 *  instances, while writing in the same buffer.
 
	 * @param output The output to write the encoded text to.
 
	 * @param param_count The number of parameters that are in the string.
 
	 * @param seen_ids The list of seen StringID.
 
	 */
 
	void _GetEncodedText(std::back_insert_iterator<std::string> &output, int &param_count, StringIDList &seen_ids);
 
	void _GetEncodedText(std::back_insert_iterator<std::string> &output, int &param_count, StringIDList &seen_ids, ParamSpan args);
 

	
 
	/**
 
	 * Set a parameter, where the value is the first item on the stack.
0 comments (0 inline, 0 general)