Apply same performance optimizations to wsssh C version as wsscp

- Replace blocking recv() with select() for efficient I/O multiplexing
- Add 50ms timeouts to prevent indefinite blocking operations
- Increase buffer size from 4KB to 1MB for optimal throughput
- Add 3-second exit delay after SSH completion for clean shutdown
- Fix setup_tunnel return codes to prevent segmentation faults
- Correct memory management in argument cleanup

wssshtools/wsssh.c

@@ -32,8 +32,9 @@
 #include <sys/wait.h>
 #include <fcntl.h>
 #include <pthread.h>
+#include <sys/select.h>
 
-#define BUFFER_SIZE 4096
+#define BUFFER_SIZE 1048576
 #define DEFAULT_PORT 22
 
 typedef struct {
@@ -450,6 +451,8 @@ void *forward_tcp_to_ws(void *arg) {
     int debug = args->debug;
     char buffer[BUFFER_SIZE];
     int bytes_read;
+    fd_set readfds;
+    struct timeval tv;
 
     while (1) {
         pthread_mutex_lock(&tunnel_mutex);
@@ -462,6 +465,25 @@ void *forward_tcp_to_ws(void *arg) {
         strcpy(request_id, active_tunnel->request_id);
         pthread_mutex_unlock(&tunnel_mutex);
 
+        // Use select to wait for data on local socket
+        FD_ZERO(&readfds);
+        FD_SET(sock, &readfds);
+        tv.tv_sec = 0;  // 0 seconds
+        tv.tv_usec = 50000;  // 50ms timeout
+
+        int retval = select(sock + 1, &readfds, NULL, NULL, &tv);
+        if (retval == -1) {
+            if (debug) {
+                perror("[DEBUG] select failed");
+                fflush(stdout);
+            }
+            break;
+        } else if (retval == 0) {
+            // Timeout, continue loop
+            continue;
+        }
+
+        if (FD_ISSET(sock, &readfds)) {
             bytes_read = recv(sock, buffer, sizeof(buffer), 0);
             if (bytes_read <= 0) {
                 if (debug) {
@@ -497,6 +519,7 @@ void *forward_tcp_to_ws(void *arg) {
                 break;
             }
         }
+    }
 
     if (debug) {
         printf("[DEBUG] TCP to WebSocket forwarding thread exiting\n");
@@ -560,13 +583,13 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
     // Resolve hostname
     if ((he = gethostbyname(wssshd_host)) == NULL) {
         herror("gethostbyname");
-        return 0;
+        return -1;
     }
 
     // Create socket
     if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
         perror("Socket creation failed");
-        return 0;
+        return -1;
     }
 
     memset(&server_addr, 0, sizeof(server_addr));
@@ -578,7 +601,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
     if (connect(sock, (struct sockaddr *)&server_addr, sizeof(server_addr)) < 0) {
         perror("Connection failed");
         close(sock);
-        return 0;
+        return -1;
     }
 
     // Initialize SSL
@@ -590,7 +613,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
     if (!ssl_ctx) {
         ERR_print_errors_fp(stderr);
         close(sock);
-        return 0;
+        return -1;
     }
 
     // Allow self-signed certificates
@@ -609,7 +632,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
     if (debug) {
         printf("[DEBUG] SSL connection established\n");
@@ -626,7 +649,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
     if (debug) {
         printf("[DEBUG] WebSocket handshake successful\n");
@@ -638,7 +661,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     if (debug) {
@@ -654,7 +677,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     if (debug) {
@@ -688,7 +711,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     // Parse WebSocket frame
@@ -707,7 +730,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     // Null terminate payload
@@ -733,7 +756,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     if (debug) {
@@ -747,7 +770,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     strcpy(active_tunnel->request_id, request_id);
@@ -764,7 +787,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     struct sockaddr_in local_addr;
@@ -781,7 +804,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     if (listen(listen_sock, 1) < 0) {
@@ -792,7 +815,7 @@ int setup_tunnel(const char *wssshd_host, int wssshd_port, const char *client_id
         SSL_free(ssl);
         SSL_CTX_free(ssl_ctx);
         close(sock);
-        return 0;
+        return -1;
     }
 
     if (debug) {
@@ -1034,7 +1057,30 @@ int main(int argc, char *argv[]) {
     // Main tunnel loop - handle WebSocket messages
     char buffer[BUFFER_SIZE];
     int bytes_read;
+    fd_set readfds;
+    struct timeval tv;
+    int ssl_fd = SSL_get_fd(active_tunnel->ssl);
+
     while (active_tunnel && active_tunnel->active) {
+        // Use select to wait for data on SSL socket with timeout
+        FD_ZERO(&readfds);
+        FD_SET(ssl_fd, &readfds);
+        tv.tv_sec = 0;  // 0 seconds
+        tv.tv_usec = 50000;  // 50ms timeout
+
+        int retval = select(ssl_fd + 1, &readfds, NULL, NULL, &tv);
+        if (retval == -1) {
+            if (config.debug) {
+                perror("[DEBUG] select on SSL fd failed");
+                fflush(stdout);
+            }
+            break;
+        } else if (retval == 0) {
+            // Timeout, continue loop
+            continue;
+        }
+
+        if (FD_ISSET(ssl_fd, &readfds)) {
             bytes_read = SSL_read(active_tunnel->ssl, buffer, sizeof(buffer));
             if (bytes_read <= 0) {
                 if (config.debug) {
@@ -1131,6 +1177,7 @@ int main(int argc, char *argv[]) {
                 }
             }
         }
+    }
 
     if (config.debug) {
         printf("[DEBUG] Tunnel loop ended, waiting for SSH to finish...\n");
@@ -1146,6 +1193,13 @@ int main(int argc, char *argv[]) {
         fflush(stdout);
     }
 
+    // Wait a few seconds before exiting cleanly
+    if (config.debug) {
+        printf("[DEBUG] Waiting 3 seconds before exit...\n");
+        fflush(stdout);
+    }
+    sleep(3);
+
     // Cleanup
     if (active_tunnel) {
         close(active_tunnel->local_sock);