GUACAMOLE-1841: Attempt to fix socket issues from rebase.

src/common-ssh/ssh.c

@@ -426,8 +426,14 @@ guac_common_ssh_session* guac_common_ssh_create_session(guac_client* client,
         int timeout, int keepalive, const char* host_key,
         guac_ssh_credential_handler* credential_handler) {
 
+#ifdef WINDOWS_BUILD
+    SOCKET fd = guac_tcp_connect(hostname, port, timeout);
+    if (fd == INVALID_SOCKET) {
+#else
     int fd = guac_tcp_connect(hostname, port, timeout);
     if (fd < 0) {
+#endif
+
         guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
             "Failed to open TCP connection to %s on %s.", hostname, port);
         return NULL;
@@ -464,7 +470,11 @@ guac_common_ssh_session* guac_common_ssh_create_session(guac_client* client,
         guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_ERROR,
                 "SSH handshake failed.");
         guac_mem_free(common_session);
+#ifdef WINDOWS_BUILD
+        closesocket(fd);
+#else
         close(fd);
+#endif
         return NULL;
     }
 
@@ -477,7 +487,11 @@ guac_common_ssh_session* guac_common_ssh_create_session(guac_client* client,
         guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
             "Failed to get host key for %s", hostname);
         guac_mem_free(common_session);
+#ifdef WINDOWS_BUILD
+        closesocket(fd);
+#else
         close(fd);
+#endif
         return NULL;
     }
 
@@ -500,7 +514,11 @@ guac_common_ssh_session* guac_common_ssh_create_session(guac_client* client,
                 "Host key did not match any provided known host keys. %s", err_msg);
 
         guac_mem_free(common_session);
+#ifdef WINDOWS_BUILD
+        closesocket(fd);
+#else
         close(fd);
+#endif
         return NULL;
     }
 
@@ -514,7 +532,11 @@ guac_common_ssh_session* guac_common_ssh_create_session(guac_client* client,
     /* Attempt authentication */
     if (guac_common_ssh_authenticate(common_session)) {
         guac_mem_free(common_session);
+#ifdef WINDOWS_BUILD
+        closesocket(fd);
+#else
         close(fd);
+#endif
         return NULL;
     }
 

src/libguac/guacamole/tcp.h

@@ -30,13 +30,25 @@
 
 #include <stddef.h>
 
+#ifdef WINDOWS_BUILD
+#include <winsock2.h>
+#endif
+
 /**
+ * Linux:
  * Given a hostname or IP address and port, attempt to connect to that system,
  * returning the file descriptor of an open socket if the connection succeeds,
  * or a negative value if it fails. The returned file descriptor must
  * eventually be freed with a call to close(). If this function fails,
  * guac_error will be set appropriately.
  *
+ * Windows:
+ * Given a hostname or IP address and port, attempt to connect to that system,
+ * returning A SOCKET representing an open socket if the connection succeeds,
+ * or INVALID_SOCKET if it fails. The returned socket must eventually be freed
+ * with a call to closesocket(). If this function fails, guac_error will be set
+ * appropriately.
+ *
  * @param hostname
  *     The hostname or IP address to which to attempt connections.
  *
@@ -50,6 +62,10 @@
  *     A valid socket if the connection succeeds, or a negative integer if it
  *     fails.
  */
+#ifdef WINDOWS_BUILD
+SOCKET guac_tcp_connect(const char* hostname, const char* port, const int timeout);
+#else
 int guac_tcp_connect(const char* hostname, const char* port, const int timeout);
+#endif
 
 #endif // GUAC_TCP_H

src/libguac/tcp.c

@@ -23,6 +23,7 @@
 
 #include <errno.h>
 #include <fcntl.h>
+#include <stdio.h>
 
 #ifdef WINDOWS_BUILD
 #include <winsock2.h>
@@ -35,7 +36,12 @@
 #include <unistd.h>
 #endif
 
+#ifdef WINDOWS_BUILD
+SOCKET guac_tcp_connect(const char* hostname, const char* port, const int timeout) {
+    SOCKET sock = INVALID_SOCKET;
+#else
 int guac_tcp_connect(const char* hostname, const char* port, const int timeout) {
+#endif
 
     int retval;
 
@@ -75,6 +81,47 @@ int guac_tcp_connect(const char* hostname, const char* port, const int timeout)
             continue;
         }
 
+#ifdef WINDOWS_BUILD
+
+        /* Get socket or return the error. */
+        SOCKET sock = socket(current_address->ai_family, SOCK_STREAM, 0);
+        if (fd < 0) {
+            freeaddrinfo(addresses);
+            return fd;
+        }
+
+        /* Sockets are always created in blocking mode in WinAPI. See
+        https://learn.microsoft.com/en-us/windows/win32/winsock/winsock-ioctls#fionbio
+        */
+        u_long blocking_mode = 0;
+        if(ioctlsocket(sock, FIONBIO, &blocking_mode) != NO_ERROR) {
+            guac_error = GUAC_STATUS_INVALID_ARGUMENT;
+            guac_error_message = "Failed to set non-blocking socket.";
+            close(fd);
+            continue;
+        }
+
+        /* Get socket or return the error. WSAGetLastError() is expected
+           to return WSAEWOULDBLOCK for non-blocking sockets. */
+        sock = socket(current_address->ai_family, SOCK_STREAM, 0);
+        if (sock == SOCKET_ERROR && WSAGetLastError() != WSAEWOULDBLOCK) {
+            freeaddrinfo(addresses);
+            return fd;
+        }
+
+        /* Structure that stores our timeout setting. */
+        struct timeval tv;
+        tv.tv_sec = timeout;
+        tv.tv_usec = 0;
+
+        /* Set up timeout. */
+        fd_set fdset;
+        FD_ZERO(&fdset);
+        FD_SET(sock, &fdset);
+
+        int retval = select(sock, NULL, &fdset, NULL, &tv);
+#else
+
         /* Get socket or return the error. */
         fd = socket(current_address->ai_family, SOCK_STREAM, 0);
         if (fd < 0) {
@@ -124,16 +171,30 @@ int guac_tcp_connect(const char* hostname, const char* port, const int timeout)
                 continue;
             }
         }
-
+#endif
         /* Successful connection */
         if (retval > 0) {
+
+#ifdef WINDOWS_BUILD
+
+            // Set the socket back to blocking mode
+            blocking_mode = 1;
+            if(ioctlsocket(sock, FIONBIO, &blocking_mode) != NO_ERROR) {
+                guac_error = GUAC_STATUS_INVALID_ARGUMENT;
+                guac_error_message = "Failed to reset socket options.";
+                close(fd);
+                continue;
+            }
+#else
+
             /* Restore previous socket options. */
             if (fcntl(fd, F_SETFL, opt) < 0) {
                 guac_error = GUAC_STATUS_INVALID_ARGUMENT;
                 guac_error_message = "Failed to reset socket options.";
                 close(fd);
                 continue;
             }
+#endif
 
             break;
         }
@@ -161,7 +222,11 @@ int guac_tcp_connect(const char* hostname, const char* port, const int timeout)
         guac_error_message = "Unable to connect to remote host.";
     }
 
-    /* Return the fd, or the error message if the socket connection failed. */
+    /* Return the socket, or the error message if the socket connection failed. */
+#ifdef WINDOWS_BUILD
+    return sock;
+#else
     return fd;
+#endif
 
 }

src/libguac/wol.c

@@ -210,6 +210,21 @@ int guac_wol_wake_and_wait(const char* mac_addr, const char* broadcast_addr,
         const char* hostname, const char* port, const int timeout) {
 
     /* Attempt to connect, first. */
+#ifdef WINDOWS_BUILD
+
+    SOCKET sockfd = guac_tcp_connect(hostname, port, timeout);
+
+    /* If connection succeeds, no need to wake the system. */
+    if (sockfd != INVALID_SOCKET) {
+        closesocket(sockfd);
+        return 0;
+    }
+
+    /* Close the fd to avoid resource leak. */
+    closesocket(sockfd);
+
+#else
+
     int sockfd = guac_tcp_connect(hostname, port, timeout);
 
     /* If connection succeeds, no need to wake the system. */
@@ -221,6 +236,8 @@ int guac_wol_wake_and_wait(const char* mac_addr, const char* broadcast_addr,
     /* Close the fd to avoid resource leak. */
     close(sockfd);
 
+#endif
+
     /* Send the magic WOL packet and store return value. */
     int retval = guac_wol_wake(mac_addr, broadcast_addr, udp_port);
 
@@ -235,15 +252,23 @@ int guac_wol_wake_and_wait(const char* mac_addr, const char* broadcast_addr,
 
         /* Connection succeeded - close socket and exit. */
         if (sockfd > 0) {
-            close(sockfd);
+#ifdef WINDOWS_BUILD
+        closesocket(sockfd);
+#else
+        close(sockfd);
+#endif
             return 0;
         }
 
         /**
          * Connection did not succed - close the socket and sleep for the
          * specified amount of time before retrying.
          */
+#ifdef WINDOWS_BUILD
+        closesocket(sockfd);
+#else
         close(sockfd);
+#endif
         guac_timestamp_msleep(wait_time * 1000);
     }
 

src/protocols/telnet/telnet.c

@@ -401,7 +401,11 @@ static telnet_t* __guac_telnet_create_session(guac_client* client) {
     guac_telnet_client* telnet_client = (guac_telnet_client*) client->data;
     guac_telnet_settings* settings = telnet_client->settings;
 
+#ifdef WINDOWS_BUILD
+    SOCKET fd = guac_tcp_connect(settings->hostname, settings->port, settings->timeout);
+#else
     int fd = guac_tcp_connect(settings->hostname, settings->port, settings->timeout);
+#endif
 
     /* Open telnet session */
     telnet_t* telnet = telnet_init(__telnet_options, __guac_telnet_event_handler, 0, client);