1 files changed, 284 insertions, 0 deletions
diff --git a/src/lib/cc/command_interpreter.cc b/src/lib/cc/command_interpreter.cc
new file mode 100644
index 0000000..68f880c
--- /dev/null
+++ b/src/lib/cc/command_interpreter.cc
@@ -0,0 +1,284 @@
+// Copyright (C) 2009-2022 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#include <config.h>
+
+#include <exceptions/exceptions.h>
+#include <cc/command_interpreter.h>
+#include <cc/data.h>
+#include <string>
+#include <set>
+
+using namespace std;
+
+using isc::data::Element;
+using isc::data::ConstElementPtr;
+using isc::data::ElementPtr;
+using isc::data::JSONError;
+
+namespace isc {
+namespace config {
+
+const char *CONTROL_COMMAND = "command";
+const char *CONTROL_RESULT = "result";
+const char *CONTROL_TEXT = "text";
+const char *CONTROL_ARGUMENTS = "arguments";
+const char *CONTROL_SERVICE = "service";
+const char *CONTROL_REMOTE_ADDRESS = "remote-address";
+
+// Full version, with status, text and arguments
+ConstElementPtr
+createAnswer(const int status_code, const std::string& text,
+             const ConstElementPtr& arg) {
+    if (status_code != 0 && text.empty()) {
+        isc_throw(CtrlChannelError, "Text has to be provided for status_code != 0");
+    }
+
+    ElementPtr answer = Element::createMap();
+    ElementPtr result = Element::create(status_code);
+    answer->set(CONTROL_RESULT, result);
+
+    if (!text.empty()) {
+        answer->set(CONTROL_TEXT, Element::create(text));
+    }
+    if (arg) {
+        answer->set(CONTROL_ARGUMENTS, arg);
+    }
+    return (answer);
+}
+
+ConstElementPtr
+createAnswer() {
+    return (createAnswer(0, string(""), ConstElementPtr()));
+}
+
+ConstElementPtr
+createAnswer(const int status_code, const std::string& text) {
+    return (createAnswer(status_code, text, ElementPtr()));
+}
+
+ConstElementPtr
+createAnswer(const int status_code, const ConstElementPtr& arg) {
+    return (createAnswer(status_code, "", arg));
+}
+
+ConstElementPtr
+parseAnswer(int &rcode, const ConstElementPtr& msg) {
+    if (!msg) {
+        isc_throw(CtrlChannelError, "No answer specified");
+    }
+    if (msg->getType() != Element::map) {
+        isc_throw(CtrlChannelError,
+                  "Invalid answer Element specified, expected map");
+    }
+    if (!msg->contains(CONTROL_RESULT)) {
+        isc_throw(CtrlChannelError,
+                  "Invalid answer specified, does not contain mandatory 'result'");
+    }
+
+    ConstElementPtr result = msg->get(CONTROL_RESULT);
+    if (result->getType() != Element::integer) {
+            isc_throw(CtrlChannelError,
+                      "Result element in answer message is not a string");
+    }
+
+    rcode = result->intValue();
+
+    // If there are arguments, return them.
+    ConstElementPtr args = msg->get(CONTROL_ARGUMENTS);
+    if (args) {
+        return (args);
+    }
+
+    // There are no arguments, let's try to return just the text status
+    return (msg->get(CONTROL_TEXT));
+}
+
+std::string
+answerToText(const ConstElementPtr& msg) {
+    if (!msg) {
+        isc_throw(CtrlChannelError, "No answer specified");
+    }
+    if (msg->getType() != Element::map) {
+        isc_throw(CtrlChannelError,
+                  "Invalid answer Element specified, expected map");
+    }
+    if (!msg->contains(CONTROL_RESULT)) {
+        isc_throw(CtrlChannelError,
+                  "Invalid answer specified, does not contain mandatory 'result'");
+    }
+
+    ConstElementPtr result = msg->get(CONTROL_RESULT);
+    if (result->getType() != Element::integer) {
+            isc_throw(CtrlChannelError,
+                      "Result element in answer message is not a string");
+    }
+
+    stringstream txt;
+    int rcode = result->intValue();
+    if (rcode == 0) {
+        txt << "success(0)";
+    } else {
+        txt << "failure(" << rcode << ")";
+    }
+
+    // Was any text provided? If yes, include it.
+    ConstElementPtr txt_elem = msg->get(CONTROL_TEXT);
+    if (txt_elem) {
+        txt << ", text=" << txt_elem->stringValue();
+    }
+
+    return (txt.str());
+}
+
+ConstElementPtr
+createCommand(const std::string& command) {
+    return (createCommand(command, ElementPtr(), ""));
+}
+
+ConstElementPtr
+createCommand(const std::string& command, ConstElementPtr arg) {
+    return (createCommand(command, arg, ""));
+}
+
+ConstElementPtr
+createCommand(const std::string& command, const std::string& service) {
+    return (createCommand(command, ElementPtr(), service));
+}
+
+ConstElementPtr
+createCommand(const std::string& command,
+              ConstElementPtr arg,
+              const std::string& service) {
+    ElementPtr query = Element::createMap();
+    ElementPtr cmd = Element::create(command);
+    query->set(CONTROL_COMMAND, cmd);
+    if (arg) {
+        query->set(CONTROL_ARGUMENTS, arg);
+    }
+    if (!service.empty()) {
+        ElementPtr services = Element::createList();
+        services->add(Element::create(service));
+        query->set(CONTROL_SERVICE, services);
+    }
+    return (query);
+}
+
+std::string
+parseCommand(ConstElementPtr& arg, ConstElementPtr command) {
+    if (!command) {
+        isc_throw(CtrlChannelError, "No command specified");
+    }
+    if (command->getType() != Element::map) {
+        isc_throw(CtrlChannelError, "Invalid command Element specified, expected map");
+    }
+    if (!command->contains(CONTROL_COMMAND)) {
+        isc_throw(CtrlChannelError,
+                  "Invalid answer specified, does not contain mandatory 'command'");
+    }
+
+    // Make sure that all specified parameters are supported.
+    auto command_params = command->mapValue();
+    for (auto param : command_params) {
+        if ((param.first != CONTROL_COMMAND) &&
+            (param.first != CONTROL_ARGUMENTS) &&
+            (param.first != CONTROL_SERVICE) &&
+            (param.first != CONTROL_REMOTE_ADDRESS)) {
+            isc_throw(CtrlChannelError, "Received command contains unsupported "
+                      "parameter '" << param.first << "'");
+        }
+    }
+
+    ConstElementPtr cmd = command->get(CONTROL_COMMAND);
+    if (cmd->getType() != Element::string) {
+        isc_throw(CtrlChannelError,
+                  "'command' element in command message is not a string");
+    }
+
+    arg = command->get(CONTROL_ARGUMENTS);
+
+    return (cmd->stringValue());
+}
+
+std::string
+parseCommandWithArgs(ConstElementPtr& arg, ConstElementPtr command) {
+    std::string command_name = parseCommand(arg, command);
+
+    // This function requires arguments within the command.
+    if (!arg) {
+        isc_throw(CtrlChannelError,
+                  "no arguments specified for the '" << command_name
+                  << "' command");
+    }
+
+    // Arguments must be a map.
+    if (arg->getType() != Element::map) {
+        isc_throw(CtrlChannelError, "arguments specified for the '" << command_name
+                  << "' command are not a map");
+    }
+
+    // At least one argument is required.
+    if (arg->size() == 0) {
+        isc_throw(CtrlChannelError, "arguments must not be empty for "
+                  "the '" << command_name << "' command");
+    }
+
+    return (command_name);
+}
+
+ConstElementPtr
+combineCommandsLists(const ConstElementPtr& response1,
+                     const ConstElementPtr& response2) {
+    // Usually when this method is called there should be two non-null
+    // responses. If there is just a single response, return this
+    // response.
+    if (!response1 && response2) {
+        return (response2);
+
+    } else if (response1 && !response2) {
+        return (response1);
+
+    } else if (!response1 && !response2) {
+        return (ConstElementPtr());
+
+    } else {
+        // Both responses are non-null so we need to combine the lists
+        // of supported commands if the status codes are 0.
+        int status_code;
+        ConstElementPtr args1 = parseAnswer(status_code, response1);
+        if (status_code != 0) {
+            return (response1);
+        }
+
+        ConstElementPtr args2 = parseAnswer(status_code, response2);
+        if (status_code != 0) {
+            return (response2);
+        }
+
+        const std::vector<ElementPtr> vec1 = args1->listValue();
+        const std::vector<ElementPtr> vec2 = args2->listValue();
+
+        // Storing command names in a set guarantees that the non-unique
+        // command names are aggregated.
+        std::set<std::string> combined_set;
+        for (auto v = vec1.cbegin(); v != vec1.cend(); ++v) {
+            combined_set.insert((*v)->stringValue());
+        }
+        for (auto v = vec2.cbegin(); v != vec2.cend(); ++v) {
+            combined_set.insert((*v)->stringValue());
+        }
+
+        // Create a combined list of commands.
+        ElementPtr combined_list = Element::createList();
+        for (auto s = combined_set.cbegin(); s != combined_set.cend(); ++s) {
+            combined_list->add(Element::create(*s));
+        }
+        return (createAnswer(CONTROL_RESULT_SUCCESS, combined_list));
+    }
+}
+
+}
+}