CMakeLists.txt

@@ -12,7 +12,7 @@ endif()
 project ("shell-server")
 
 # Добавьте источник в исполняемый файл этого проекта.
-add_executable (shell-server "main.c" "server.c" "server.h" "client.c" "client.h")
+add_executable (shell-server "main.c" "server.c" "server.h")
 
 if (CMAKE_VERSION VERSION_GREATER 3.12)
   set_property(TARGET shell-server PROPERTY CXX_STANDARD 20)

main.c

@@ -3,38 +3,31 @@
 
 #include "server.h"
 
-int _tmain(int argc, char *argv[]) {
+void PrintHelpMessage() {
+    printf("Usage error: I know 3 arguments \n\t\"install\"\n\t\"delete\"\n\t\"app\"\n");
+}
+
+int _tmain(int argc, TCHAR *argv[]) {
+    printf("\n->Start of parent execution.\n");
     if (argc == 2) {
-        if (lstrcmpi(argv[1], TEXT("-s")) == 0) {
+        if (lstrcmpi(argv[1], TEXT("-c")) == 0) {
+            return 0;
+        }
+        else if (lstrcmpi(argv[1], TEXT("-s")) == 0) {
             StartShellServer();
             return 0;
         }
         else {
-            goto help_message;
+            PrintHelpMessage();
+            return -1;
         }
 
     }
-    else if (argc == 3) {
-        if (lstrcmpi(argv[1], TEXT("-c")) == 0) {
-            StartShellClient(argv[2]);
-            return 0;
-        }
-        // TODO: implement service
-        else if (lstrcmpi(argv[1], TEXT("-s")) == 0 && lstrcmpi(argv[2], TEXT("-service")) == 0) {
-            // CreateService
-            return 0;
-        }
-        else {
-            goto help_message;
-        }
-    }
     else {
-        goto help_message;
+        PrintHelpMessage();
+        return -1;
     }
 
     return 0;
-help_message:
-    printf("Wrong usage\nUsage: %s [-c {remote ip} | -s [-service]]\n", argv[0]);
-    return -1;
 }
 

server.c

@@ -1,32 +1,77 @@
 #include "server.h"
 
 #define BUFSIZE 4096
+#define DEFAULT_PORT "50113"
 #define DEFAULT_BUFLEN 512
 
-typedef struct PipeThreadInfo_t {
+// Handles for child process STDIN and STDOUT
-    HANDLE Pipe;
+HANDLE g_hChildStd_IN_Rd = NULL;
-    SOCKET ClientSocket;
+HANDLE g_hChildStd_IN_Wr = NULL;
-} PipeThreadInfo;
+HANDLE g_hChildStd_OUT_Rd = NULL;
+HANDLE g_hChildStd_OUT_Wr = NULL;
 
-void CreateChildProcess(HANDLE g_hChildStd_IN_Rd, HANDLE g_hChildStd_OUT_Wr);
+SOCKET ClientSocket = INVALID_SOCKET;
-DWORD WINAPI WorkWithClient(LPVOID lpParam);
+
-DWORD WINAPI WriteToPipe(LPVOID lpParam);
+//HANDLE g_hInputFile = NULL;
-DWORD WINAPI ReadFromPipe(LPVOID lpParam);
-void ErrorExit(PCTSTR);
 
 void StartShellServer() {
     printf("\n->Start of shell server execution.\n");
 
+    CreatePipes();
+    CreateSocket();
+
+    // Create the child process. 
+    CreateChildProcess();
+
+    // TODO: split into threads
+    WriteToPipe();
+    // Read from pipe that is the standard output for child process. 
+    ReadFromPipe();
+
+    printf("\n->End of shell server execution.\n");
+
+    // The remaining open handles are cleaned up when this process terminates. 
+    // To avoid resource leaks in a larger application, close handles explicitly. 
+
+}
+
+void CreatePipes() {
+    SECURITY_ATTRIBUTES saAttr;
+
+    // Set the bInheritHandle flag so pipe handles are inherited. 
+
+    saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
+    saAttr.bInheritHandle = TRUE;
+    saAttr.lpSecurityDescriptor = NULL;
+
+    // Create a pipe for the child process's STDOUT. 
+
+    if (!CreatePipe(&g_hChildStd_OUT_Rd, &g_hChildStd_OUT_Wr, &saAttr, 0))
+        ErrorExit(TEXT("StdoutRd CreatePipe"));
+
+    // Ensure the read handle to the pipe for STDOUT is not inherited.
+
+    if (!SetHandleInformation(g_hChildStd_OUT_Rd, HANDLE_FLAG_INHERIT, 0))
+        ErrorExit(TEXT("Stdout SetHandleInformation"));
+
+    // Create a pipe for the child process's STDIN. 
+
+    if (!CreatePipe(&g_hChildStd_IN_Rd, &g_hChildStd_IN_Wr, &saAttr, 0))
+        ErrorExit(TEXT("Stdin CreatePipe"));
+
+    // Ensure the write handle to the pipe for STDIN is not inherited. 
+
+    if (!SetHandleInformation(g_hChildStd_IN_Wr, HANDLE_FLAG_INHERIT, 0))
+        ErrorExit(TEXT("Stdin SetHandleInformation"));
+}
+
+// TODO: to review
+void CreateSocket() {
     WSADATA wsaData;
     struct addrinfo* result = NULL, * ptr = NULL, hints;
-    int iResult;
-
-    SOCKET ClientSocket = INVALID_SOCKET;
     SOCKET ListenSocket = INVALID_SOCKET;
 
-    /*
+    int iResult;
-    * Initialize listening socket
-    */
 
     // Initialize Winsock
     iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
@@ -80,87 +125,22 @@ void StartShellServer() {
         return 1;
     }
 
-    /*
+    // Accepting a connection
-    * Process client connection
+    ClientSocket = INVALID_SOCKET;
-    */
-    for (;;) {
-        // Accepting a client connection
-        ClientSocket = INVALID_SOCKET;
 
-        ClientSocket = accept(ListenSocket, NULL, NULL);
+    // Accept a client socket
-        if (ClientSocket == INVALID_SOCKET) {
+    ClientSocket = accept(ListenSocket, NULL, NULL);
-            printf("accept failed: %d\n", WSAGetLastError());
+    if (ClientSocket == INVALID_SOCKET) {
-            break;
+        printf("accept failed: %d\n", WSAGetLastError());
-        }
+        closesocket(ListenSocket);
-        printf("Client connected\n");
+        WSACleanup();
-        // Create separate thread to process client connection
+        return 1;
-        CreateThread(NULL, 0, WorkWithClient, ClientSocket, 0, NULL);
     }
-
+    // No longer needed
-    /*
-    * Finalization
-    */
-    // TODO: properly close all handles
     closesocket(ListenSocket);
-    WSACleanup();
 }
 
-DWORD WINAPI WorkWithClient(LPVOID lpParam) {
+void CreateChildProcess()
-    /*
-    * Client variables
-    */
-    // Pipe handles for child STDIN/STDOUT
-    HANDLE g_hChildStd_IN_Rd = NULL;
-    HANDLE g_hChildStd_IN_Wr = NULL;
-    HANDLE g_hChildStd_OUT_Rd = NULL;
-    HANDLE g_hChildStd_OUT_Wr = NULL;
-
-    SECURITY_ATTRIBUTES saAttr;
-    HANDLE PipeThreads[2];
-
-    SOCKET ClientSocket = (SOCKET)lpParam;
-
-    /*
-    * Initialize pipes
-    */
-    // Set the bInheritHandle flag so pipe handles are inherited. 
-    saAttr.nLength = sizeof(SECURITY_ATTRIBUTES);
-    saAttr.bInheritHandle = TRUE;
-    saAttr.lpSecurityDescriptor = NULL;
-
-    // Create a pipe for the child process's STDOUT. 
-    if (!CreatePipe(&g_hChildStd_OUT_Rd, &g_hChildStd_OUT_Wr, &saAttr, 0))
-        ErrorExit(TEXT("StdoutRd CreatePipe"));
-
-    // Ensure the read handle to the pipe for STDOUT is not inherited.
-    if (!SetHandleInformation(g_hChildStd_OUT_Rd, HANDLE_FLAG_INHERIT, 0))
-        ErrorExit(TEXT("Stdout SetHandleInformation"));
-
-    // Create a pipe for the child process's STDIN. 
-    if (!CreatePipe(&g_hChildStd_IN_Rd, &g_hChildStd_IN_Wr, &saAttr, 0))
-        ErrorExit(TEXT("Stdin CreatePipe"));
-
-    // Ensure the write handle to the pipe for STDIN is not inherited. 
-    if (!SetHandleInformation(g_hChildStd_IN_Wr, HANDLE_FLAG_INHERIT, 0))
-        ErrorExit(TEXT("Stdin SetHandleInformation"));
-
-    /*
-    * Create child process cmd.exe
-    */
-    CreateChildProcess(g_hChildStd_IN_Rd, g_hChildStd_OUT_Wr);
-
-    // Create threads for STDIN/STDOUT
-    PipeThreadInfo WriteThreadInfo = { g_hChildStd_IN_Wr, ClientSocket };
-    PipeThreadInfo ReadThreadInfo = { g_hChildStd_OUT_Rd, ClientSocket };
-    PipeThreads[0] = CreateThread(NULL, 0, WriteToPipe, &WriteThreadInfo, 0, NULL);
-    PipeThreads[1] = CreateThread(NULL, 0, ReadFromPipe, &ReadThreadInfo, 0, NULL);
-
-    WaitForMultipleObjects(2, PipeThreads, TRUE, INFINITE);
-
-    printf("\n->Client disconnected.\n");
-}
-
-void CreateChildProcess(HANDLE g_hChildStd_IN_Rd, HANDLE g_hChildStd_OUT_Wr)
 // Create a child process that uses the previously created pipes for STDIN and STDOUT.
 {
     TCHAR szCmdline[] = TEXT("C:\\Windows\\System32\\cmd.exe");
@@ -215,31 +195,36 @@ void CreateChildProcess(HANDLE g_hChildStd_IN_Rd, HANDLE g_hChildStd_OUT_Wr)
     }
 }
 
-DWORD WINAPI WriteToPipe(LPVOID lpParam)
+void WriteToPipe(void)
+
+// Read from a file and write its contents to the pipe for the child's STDIN.
+// Stop when there is no more data. 
 {
     DWORD dwRead, dwWritten;
+    //CHAR chBuf[BUFSIZE] = "dir\r\n";
     BOOL bSuccess = FALSE;
     int i = 0;
 
-    SOCKET ClientSocket = ((PipeThreadInfo*)lpParam)->ClientSocket;
-    HANDLE g_hChildStd_IN_Wr = ((PipeThreadInfo*)lpParam)->Pipe;
-
     char recvbuf[DEFAULT_BUFLEN];
     int iResult, iSendResult;
     int recvbuflen = DEFAULT_BUFLEN;
     
-    // Change codepage to UTF-8
-    //CHAR chcpCommand[] = "chcp 65001\n";
-    //bSuccess = WriteFile(g_hChildStd_IN_Wr, chcpCommand, strlen(chcpCommand), &dwWritten, NULL);
-    //if (!bSuccess) goto WriteToPipe_end;
 
     do
     {
         iResult = recv(ClientSocket, recvbuf, recvbuflen, 0);
         if (iResult > 0) {
-            bSuccess = WriteFile(g_hChildStd_IN_Wr, recvbuf, iResult, &dwWritten, NULL);
+            printf("Bytes received: %d\n", iResult);
-            if (!bSuccess) break;
+
-            printf("Received command: %s\n");
+            // Echo the buffer back to the sender
+            iSendResult = send(ClientSocket, recvbuf, iResult, 0);
+            if (iSendResult == SOCKET_ERROR) {
+                printf("send failed: %d\n", WSAGetLastError());
+                closesocket(ClientSocket);
+                WSACleanup();
+                return 1;
+            }
+            printf("Bytes sent: %d\n", iSendResult);
         }
         else if (iResult == 0)
             printf("Connection closing...\n");
@@ -249,34 +234,40 @@ DWORD WINAPI WriteToPipe(LPVOID lpParam)
             WSACleanup();
             return 1;
         }
+
+        //dwRead = strlen(chBuf) + 1;
+        bSuccess = WriteFile(g_hChildStd_IN_Wr, recvbuf, iResult, &dwWritten, NULL);
+        if (!bSuccess) break;
+        //break;
+        //dwRead = strlen(chBuf) + 1;
+        //bSuccess = WriteFile(g_hChildStd_IN_Wr, chBuf, dwRead, &dwWritten, NULL);
+        //if (!bSuccess) break;
+        ReadFromPipe();
     } while (iResult > 0);
 
-WriteToPipe_end:
+    // Close the pipe handle so the child process stops reading. 
-    // Closing STDIN => cmd.exe exit
+
     if (!CloseHandle(g_hChildStd_IN_Wr))
         ErrorExit(TEXT("StdInWr CloseHandle"));
 }
 
-DWORD WINAPI ReadFromPipe(LPVOID lpParam)
+void ReadFromPipe(void)
-{
-    DWORD dwRead;
-    CHAR chBuf[BUFSIZE + 1];
 
+// Read output from the child process's pipe for STDOUT
+// and write to the parent process's pipe for STDOUT. 
+// Stop when there is no more data. 
+{
+    DWORD dwRead, dwWritten;
+    CHAR chBuf[BUFSIZE];
     BOOL bSuccess = FALSE;
-    //HANDLE hParentStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
+    HANDLE hParentStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
-    SOCKET ClientSocket = ((PipeThreadInfo*)lpParam)->ClientSocket;
-    HANDLE g_hChildStd_OUT_Rd = ((PipeThreadInfo*)lpParam)->Pipe;
 
     int iSendResult;
 
-
     for (;;)
     {
         bSuccess = ReadFile(g_hChildStd_OUT_Rd, chBuf, BUFSIZE, &dwRead, NULL);
         if (!bSuccess || dwRead == 0) break;
-        printf("STDOUT: %s\n", chBuf);
-       
-        chBuf[dwRead] = '\0';
 
         iSendResult = send(ClientSocket, chBuf, dwRead, 0);
         if (iSendResult == SOCKET_ERROR) {
@@ -285,7 +276,11 @@ DWORD WINAPI ReadFromPipe(LPVOID lpParam)
             WSACleanup();
             return 1;
         }
+        // Write to console
+        bSuccess = WriteFile(hParentStdOut, chBuf,
+            dwRead, &dwWritten, NULL);
         if (!bSuccess) break;
+        break;
     }
 }
 

server.h

@@ -12,7 +12,11 @@
 #include <winsock2.h>
 #include <ws2tcpip.h>
 
-#define DEFAULT_PORT "50113"
-
 // Defined functions
 void StartShellServer();
+void CreatePipes();
+void CreateChildProcess(void);
+void WriteToPipe(void);
+void ReadFromPipe(void);
+void ErrorExit(PCTSTR);
+void CreateSocket();