tools/hexnet: Implement bi-directional communication

src/tools/hexnet.cpp

@@ -16,6 +16,7 @@
 //version 3 along with this program.
 //If not, see https://www.gnu.org/licenses/agpl-3.0.en.html
 
+#include <chrono>
 #include <csignal>
 #include <iomanip>
 #include <iostream>
@@ -23,6 +24,10 @@
 #include <string>
 #include <sockpp/tcp_acceptor.h>
 #include <sockpp/tcp_connector.h>
+#include <sockpp/tcp6_acceptor.h>
+#include <sockpp/tcp6_connector.h>
+#include <sockpp/udp_socket.h>
+#include <sockpp/udp6_socket.h>
 #include <thread>
 #include <vector>
 
@@ -33,12 +38,22 @@
 #define EXIT_RUNTIME 1
 #define EXIT_USAGE 2
 #define EXIT_UNIMPLEMENTED 3
+#define EXIT_SIGNAL 4
 
 // TCP v4 server
 sockpp::tcp_socket tcpSocket;
 sockpp::tcp_acceptor tcpAcceptor;
 // TCP v4 client
 sockpp::tcp_connector tcpConnector;
+// TCP v6 server
+sockpp::tcp6_socket tcp6Socket;
+sockpp::tcp6_acceptor tcp6Acceptor;
+// TCP v6 client
+sockpp::tcp6_connector tcp6Connector;
+// UDP v4 server and client
+sockpp::udp_socket udpSocket;
+// UDP v6 server and client
+sockpp::udp6_socket udp6Socket;
 
 bool exitProgram = false;
 
@@ -50,6 +65,44 @@ bool outgoing = false;
 std::string host;
 in_port_t port;
 
+// This is probably bigger than the MTU on any given network.
+// This should allow us to read entire packets at once when they arrive
+// slowly enough to be read individually.
+const uint32_t bufferSize = 2048;
+uint8_t networkBuffer[bufferSize];
+
+std::string readByteFromStdin() {
+    std::string input = "";
+    // read 2 characters from stdin
+    char characterInput;
+    bool readByte = false;
+    uint16_t iterationsSinceLastInput = 0;
+    while (input.length() < 2 && !exitProgram) {
+        if (std::cin.good()) {
+            std::cin.get(characterInput);
+            readByte = true;
+        } else {
+            readByte = false;
+        }
+        // ignore space, tabs, and newlines
+        if (readByte && characterInput!=' ' && characterInput!='\n' && characterInput!='\r' && characterInput!='\t') {
+            input.push_back(characterInput);
+        }
+
+        iterationsSinceLastInput++;
+        if (readByte) {
+            iterationsSinceLastInput = 0;
+        }
+        if (iterationsSinceLastInput>1024) {
+            // prevent integer overflow
+            iterationsSinceLastInput = 1024;
+
+            std::this_thread::sleep_for(std::chrono::milliseconds(1000));
+        }
+    }
+    return exitProgram? "" : std::string(1, (char) std::stoi(input, nullptr, 16));
+}
+
 void signalHandler(int signal) {
     // shut down gracefully
     exitProgram = true;
@@ -61,21 +114,136 @@ void signalHandler(int signal) {
         tcpSocket.shutdown(SHUT_RD);
     }
 
-    std::cerr << "Received signal " << signal << ", bye!" << std::endl;
-    std::exit(signal);
+    if (tcpConnector) {
+        tcpConnector.shutdown(SHUT_RD);
     }
 
-void readFromTCPSocket() {
+    if (tcp6Socket) {
+        tcp6Socket.shutdown(SHUT_RD);
+    }
+
+    if (tcp6Connector) {
+        tcp6Connector.shutdown(SHUT_RD);
+    }
+
+    if (udpSocket) {
+        udpSocket.shutdown(SHUT_RD);
+    }
+
+    if (udp6Socket) {
+        udp6Socket.shutdown(SHUT_RD);
+    }
+
+    std::cerr << "Received signal " << signal << ", bye!" << std::endl;
+    std::exit(EXIT_SIGNAL);
+}
+
+void readFromTCP() {
     ssize_t byteCount;
-    uint8_t buffer[1536];
-    while (!exitProgram && (outgoing? (byteCount = tcpConnector.read(buffer, sizeof(buffer))) > 0 : (byteCount = tcpSocket.read(buffer, sizeof(buffer))) > 0)) {
+    while (!exitProgram && (outgoing? (byteCount = tcpConnector.read(networkBuffer, bufferSize)) > 0 : (byteCount = tcpSocket.read(networkBuffer, bufferSize)) > 0)) {
         for (ssize_t i=0; i<byteCount; i++) {
-            std::cout << std::hex << std::setfill('0') << std::setw(2) << (short) buffer[i] << " ";
+            std::cout << std::hex << std::setfill('0') << std::setw(2) << (short) networkBuffer[i] << " ";
         }
         std::cout.flush();
     }
 }
 
+void writeToTCP() {
+    while (!exitProgram) {
+        if (outgoing) {
+            if (tcpConnector.write(readByteFromStdin()) == -1 && !exitProgram) {
+                exitProgram = true;
+                tcpConnector.shutdown(SHUT_RD);
+                std::cerr << "Error while sending data: " << tcpConnector.last_error_str() << std::endl;
+                return;
+            }
+        } else {
+            if (tcpSocket.write(readByteFromStdin()) == -1 && !exitProgram) {
+                exitProgram = true;
+                tcpSocket.shutdown(SHUT_RD);
+                std::cerr << "Error while sending data: " << tcpSocket.last_error_str() << std::endl;
+                return;
+            }
+        }
+    }
+}
+
+void readFromTCP6() {
+    ssize_t byteCount;
+    while (!exitProgram && (outgoing? (byteCount = tcp6Connector.read(networkBuffer, bufferSize)) > 0 : (byteCount = tcp6Socket.read(networkBuffer, bufferSize)) > 0)) {
+        for (ssize_t i=0; i<byteCount; i++) {
+            std::cout << std::hex << std::setfill('0') << std::setw(2) << (short) networkBuffer[i] << " ";
+        }
+        std::cout.flush();
+    }
+}
+
+void writeToTCP6() {
+    while (!exitProgram) {
+        if (outgoing) {
+            if (tcp6Connector.write(readByteFromStdin()) == -1 && !exitProgram) {
+                exitProgram = true;
+                tcp6Connector.shutdown(SHUT_RD);
+                std::cerr << "Error while sending data: " << tcp6Connector.last_error_str() << std::endl;
+                return;
+            }
+        } else {
+            if (tcp6Socket.write(readByteFromStdin()) == -1 && !exitProgram) {
+                exitProgram = true;
+                tcp6Socket.shutdown(SHUT_RD);
+                std::cerr << "Error while sending data: " << tcp6Socket.last_error_str() << std::endl;
+                return;
+            }
+        }
+    }
+}
+
+void readFromUDP() {
+    ssize_t byteCount;
+    sockpp::udp_socket::addr_t peer;
+    while ((byteCount = udpSocket.recv_from(networkBuffer, bufferSize, &peer)) > 0) {
+        std::cout << peer << ": ";
+        for (ssize_t i=0; i<byteCount; i++) {
+            std::cout << std::hex << std::setfill('0') << std::setw(2) << (short) networkBuffer[i] << " ";
+        }
+        std::cout << std::dec << std::endl;
+    }
+}
+
+void writeToUDP(sockpp::udp_socket::addr_t peer) {
+    while (!exitProgram) {
+        if (udpSocket.send_to(readByteFromStdin(), peer) == -1 && !exitProgram) {
+            exitProgram = true;
+            udpSocket.shutdown(SHUT_RD);
+            std::cerr << "Error while sending data: " << udpSocket.last_error_str() << std::endl;
+            return;
+        }
+    }
+}
+
+void readFromUDP6() {
+    ssize_t byteCount;
+    sockpp::udp6_socket::addr_t peer;
+    while ((byteCount = udp6Socket.recv_from(networkBuffer, bufferSize, &peer)) > 0) {
+        std::cout << peer << ": ";
+        for (ssize_t i=0; i<byteCount; i++) {
+            std::cout << std::hex << std::setfill('0') << std::setw(2) << (short) networkBuffer[i] << " ";
+        }
+        std::cout << std::dec << std::endl;
+    }
+}
+
+void writeToUDP6(sockpp::udp6_socket::addr_t peer) {
+    while (!exitProgram) {
+        if (udp6Socket.send_to(readByteFromStdin(), peer) == -1 && !exitProgram) {
+            exitProgram = true;
+            udp6Socket.shutdown(SHUT_RD);
+            std::cerr << "Error while sending data: " << udp6Socket.last_error_str() << std::endl;
+            return;
+        }
+    }
+}
+
 int main(int argc, char* argv[]) {
     std::signal(SIGINT, signalHandler);
     std::signal(SIGTERM, signalHandler);
@@ -90,11 +258,12 @@ int main(int argc, char* argv[]) {
 
     std::vector<CLI::Option> options;
     options.push_back(CLI::Option('c', "connect", "HOST", "make an outgoing connection to HOST instead of listening for an incoming connection"));
+    options.push_back(CLI::Option('b', "bind", "ADDRESS", "(UDP only) bind to ADDRESS instead of localhost"));
 
     std::vector<CLI::Argument> arguments;
     arguments.push_back(CLI::Argument("PORT", "the port to lsiten on (or connect to)"));
 
-    CLI::ArgumentsParser cliParser = CLI::ArgumentsParser(argc, argv, flags, options, arguments, "Arbitrary TCP/UDP connections in hex format", "Note: Make sure your terminal is set up so it doesn't buffer input and, if desired, disable input echoing.\n\tSomething like `stty -echo cbreak` should do but it will also disable some key combinations.");
+    CLI::ArgumentsParser cliParser = CLI::ArgumentsParser(argc, argv, flags, options, arguments, "Arbitrary TCP/UDP connections in hex format", "Spaces, tabs, newlines, and carriage returns in the input are ignored.\n\tYou may want to disable input echoing using `stty -echo` (reenable using `stty echo`).\n\tNote that many terminals do line buffering on the input by default.");
 
     if (cliParser.getFlag("help").value) {
         std::cout << cliParser.getUsage() << std::endl;
@@ -137,7 +306,7 @@ int main(int argc, char* argv[]) {
     }
 
     if (!(ipv4 || ipv6) || (ipv4 && ipv6) || !(tcp || udp) || (tcp && udp)) {
-        std::cout << cliParser.getUsage() << std::endl;
+        std::cout << "Please specify which protocols to use (one of IPv4/IPv6, one of TCP/UDP)." << std::endl;
         return EXIT_USAGE;
     }
 
@@ -155,26 +324,74 @@ int main(int argc, char* argv[]) {
                     return EXIT_RUNTIME;
                 }
 
-                std::thread threadReadFromTCP = std::thread(readFromTCPSocket);
-                //std::thread threadWriteToTCP = std::thread(writeToTCPSocket);
+                std::thread threadReadFromTCP = std::thread(readFromTCP);
+                std::thread threadWriteToTCP = std::thread(writeToTCP);
 
                 threadReadFromTCP.join();
-                //threadWriteToTCP.join();
+                threadWriteToTCP.join();
 
                 std::cout << std::endl;
                 return EXIT_SUCCESS;
             } else {
                 // TCP v6 out
-                return EXIT_UNIMPLEMENTED;
+                tcp6Connector = sockpp::tcp6_connector({host, port});
+                if (!tcp6Connector) {
+                    std::cerr << "Error connecting to " << host << " on port " << port << std::endl;
+                    std::cerr << tcp6Connector.last_error_str() << std::endl;
+                    return EXIT_RUNTIME;
+                }
+
+                std::thread threadReadFromTCP6 = std::thread(readFromTCP6);
+                std::thread threadWriteToTCP6 = std::thread(writeToTCP6);
+
+                threadReadFromTCP6.join();
+                threadWriteToTCP6.join();
+
+                std::cout << std::endl;
+                return EXIT_SUCCESS;
             }
         } else {
-            std::cerr << "Connecting to " << host << " on port " << (int) port << " (UDP)..." << std::endl;
+            std::cerr << "Talking to " << host << " on port " << (int) port << " (UDP)..." << std::endl;
             if (ipv4) {
                 // UDP v4 out
-                return EXIT_UNIMPLEMENTED;
+                if (!udpSocket) {
+                    std::cerr << "Error creating UDP socket: " << udpSocket.last_error_str() << std::endl;
+                }
+                // Btw: Did you know that UDP has no concept of a connection?
+                sockpp::udp_socket::addr_t peer = sockpp::inet_address(host, port);
+                if (!udpSocket.connect(peer)) {
+                    std::cerr << "Error associating socket with " << host << " port " << port << std::endl;
+                    std::cerr << udpSocket.last_error_str() << std::endl;
+                }
+
+                std::thread threadReadFromUDP = std::thread(readFromUDP);
+                std::thread threadWriteToUDP = std::thread(writeToUDP, peer);
+
+                threadReadFromUDP.join();
+                threadWriteToUDP.join();
+
+                std::cout << std::endl;
+                return EXIT_SUCCESS;
             } else {
                 // UDP v6 out
-                return EXIT_UNIMPLEMENTED;
+                if (!udp6Socket) {
+                    std::cerr << "Error creating UDP socket: " << udp6Socket.last_error_str() << std::endl;
+                }
+                // Btw: Did you know that UDP has no concept of a connection?
+                sockpp::udp6_socket::addr_t peer = sockpp::inet6_address(host, port);
+                if (!udp6Socket.connect(peer)) {
+                    std::cerr << "Error associating socket with " << host << " port " << port << std::endl;
+                    std::cerr << udp6Socket.last_error_str() << std::endl;
+                }
+
+                std::thread threadReadFromUDP6 = std::thread(readFromUDP6);
+                std::thread threadWriteToUDP6 = std::thread(writeToUDP6, peer);
+
+                threadReadFromUDP6.join();
+                threadWriteToUDP6.join();
+
+                std::cout << std::endl;
+                return EXIT_SUCCESS;
             }
         }
     } else {
@@ -196,26 +413,81 @@ int main(int argc, char* argv[]) {
                     return EXIT_RUNTIME;
                 }
 
-                std::thread threadReadFromTCP = std::thread(readFromTCPSocket);
-                //std::thread threadWriteToTCP = std::thread(writeToTCPSocket);
+                std::thread threadReadFromTCP = std::thread(readFromTCP);
+                std::thread threadWriteToTCP = std::thread(writeToTCP);
 
                 threadReadFromTCP.join();
-                //threadWriteToTCP.join();
+                threadWriteToTCP.join();
 
                 std::cout << std::endl;
                 return EXIT_SUCCESS;
             } else {
                 // TCP v6 in
-                return EXIT_UNIMPLEMENTED;
+                tcp6Acceptor = sockpp::tcp6_acceptor(port);
+                if (!tcp6Acceptor) {
+                    std::cerr << "Error while creating TCP acceptor: " << tcp6Acceptor.last_error_str() << std::endl;
+                    return EXIT_RUNTIME;
+                }
+
+                sockpp::inet6_address peer;
+                tcp6Socket = tcp6Acceptor.accept(&peer);
+                std::cerr << "Incoming connection from " << peer << std::endl;
+                if (!tcp6Socket) {
+                    std::cerr << "Error on incoming connection: " << tcp6Acceptor.last_error_str() << std::endl;
+                    return EXIT_RUNTIME;
+                }
+
+                std::thread threadReadFromTCP6 = std::thread(readFromTCP6);
+                std::thread threadWriteToTCP6 = std::thread(writeToTCP6);
+
+                threadReadFromTCP6.join();
+                threadWriteToTCP6.join();
+
+                std::cout << std::endl;
+                return EXIT_SUCCESS;
             }
         } else {
-            std::cerr << "Listening on port " << (int) port << " (UDP)..." << std::endl;
+            std::string address = "localhost";
+            if (cliParser.getOption("bind").errorCode != ErrorCodes::NOT_PRESENT) {
+                address = cliParser.getOption("bind").value;
+            }
+            std::cerr << "Listening on " << address << " port " << (int) port << " (UDP)..." << std::endl;
             if (ipv4) {
                 // UDP v4 in
-                return EXIT_UNIMPLEMENTED;
+                if (!udpSocket) {
+                    std::cerr << "Error creating UDP socket: " << udpSocket.last_error_str() << std::endl;
+                }
+                if (!udpSocket.bind(sockpp::inet_address(address, port))) {
+                    std::cerr << "Error binding UDP socket to " << address << " port " << port << ": " << udpSocket.last_error_str() << std::endl;
+                }
+
+                std::thread threadReadFromUDP = std::thread(readFromUDP);
+                // Can't send bc we have no idea where to send to.
+                //std::thread threadWriteToUDP = std::thread(writeToUDP);
+
+                threadReadFromUDP.join();
+                //threadWriteToUDP.join();
+
+                std::cout << std::endl;
+                return EXIT_SUCCESS;
             } else {
                 // UDP v6 in
-                return EXIT_UNIMPLEMENTED;
+                if (!udp6Socket) {
+                    std::cerr << "Error creating UDP socket: " << udp6Socket.last_error_str() << std::endl;
+                }
+                if (!udp6Socket.bind(sockpp::inet6_address(address, port))) {
+                    std::cerr << "Error binding UDP socket to " << address << " port " << port << ": " << udp6Socket.last_error_str() << std::endl;
+                }
+
+                std::thread threadReadFromUDP6 = std::thread(readFromUDP6);
+                // Can't send bc we have no idea where to send to.
+                //std::thread threadWriteToUDP6 = std::thread(writeToUDP6);
+
+                threadReadFromUDP6.join();
+                //threadWriteToUDP6.join();
+
+                std::cout << std::endl;
+                return EXIT_SUCCESS;
             }
         }
     }