First release of open-appsec source code

core/environment/parsing.cc

@@ -0,0 +1,137 @@
+// Copyright (C) 2022 Check Point Software Technologies Ltd. All rights reserved.
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "environment_evaluator.h"
+
+#include <sstream>
+#include <algorithm>
+
+#include "enum_range.h"
+
+using namespace std;
+using namespace EnvironmentHelper;
+
+USE_DEBUG_FLAG(D_ENVIRONMENT);
+
+void
+reportWrongNumberOfParams(const string &eval_name, uint no_params, uint min, uint max)
+{
+    ostringstream os;
+    os <<
+        "Wrong number of parameters for '" <<
+        eval_name <<
+        "'. Got " <<
+        no_params <<
+        " parameters instead of expected ";
+    if (min == max) {
+        os << min;
+    } else if (max == static_cast<uint>(-1)) {
+        os << "more than " << min;
+    } else {
+        os << "between " << min << " and " << max;
+    }
+    dbgTrace(D_ENVIRONMENT) << os.str();
+    EvaluatorParseError err(os.str());
+    throw err;
+}
+
+void
+reportWrongParamType(const string &eval_name, const string &param, const string &reason)
+{
+    ostringstream os;
+    os << "Parameter '" << param << "' for '" << eval_name << "' is of the wrong type because: " << reason;
+    dbgTrace(D_ENVIRONMENT) << os.str();
+
+    EvaluatorParseError err(os.str());
+    throw err;
+}
+
+void
+reportUnknownEvaluatorType(const string &eval_name)
+{
+    ostringstream os;
+    os << "Evaluator '" << eval_name << "' doesn't exist for the required type";
+    dbgTrace(D_ENVIRONMENT) << os.str();
+
+    EvaluatorParseError err(os.str());
+    throw err;
+}
+
+static string
+trim(const string &str)
+{
+    auto first = str.find_first_not_of(' ');
+    if (first == string::npos) return "";
+    auto last = str.find_last_not_of(' ');
+    return str.substr(first, (last-first+1));
+}
+
+static vector<string>
+breakToParams(const string &list)
+{
+    vector<string> res;
+
+    uint brackets = 0;
+    uint start = 0;
+    for (uint iter : makeRange(list.size())) {
+        switch (list[iter]) {
+            case ',': {
+                if (brackets == 0) {
+                    res.push_back(trim(list.substr(start, iter-start)));
+                    start = iter + 1;
+                }
+                break;
+            }
+            case '(': {
+                brackets++;
+                break;
+            }
+            case ')': {
+                brackets--;
+                break;
+            }
+            default: {
+                break;
+            }
+        }
+    }
+
+    // Add the last section
+    if (start < list.size()) res.push_back(trim(list.substr(start, list.size()-start)));
+
+    dbgTrace(D_ENVIRONMENT) << "Param vector size: " << res.size();
+    return res;
+}
+
+pair<string, vector<string>>
+EnvironmentHelper::breakEvaluatorString(const string &str)
+{
+    auto trimmed = trim(str);
+
+    auto open_bracket = trimmed.find('(');
+    if (open_bracket == string::npos) {
+        dbgTrace(D_ENVIRONMENT) << "Could not find the opening bracket in the string";
+        throw EvaluatorParseError("Could not find the opening bracket in the string");
+    }
+    auto close_bracket = trimmed.size() - 1;
+    if (trimmed[close_bracket] != ')') {
+        dbgTrace(D_ENVIRONMENT) << "Could not find the closing bracket in the string";
+        throw EvaluatorParseError("Could not find the closing bracket in the string");
+    }
+
+    auto command = trimmed.substr(0, open_bracket);
+    auto params = trimmed.substr(open_bracket + 1, close_bracket - open_bracket - 1);
+
+    dbgTrace(D_ENVIRONMENT) << "Breaking evaluator string passed successfully";
+    return make_pair(trim(command), breakToParams(trim(params)));
+}