GUACAMOLE-1686: Make WOL functionality capable of testing connectivity to the server.

src/common-ssh/ssh.c

@@ -24,6 +24,7 @@
 #include <guacamole/client.h>
 #include <guacamole/fips.h>
 #include <guacamole/mem.h>
+#include <guacamole/socket-tcp.h>
 #include <guacamole/string.h>
 #include <libssh2.h>
 
@@ -34,15 +35,11 @@
 #include <openssl/err.h>
 #include <openssl/ssl.h>
 
-#include <errno.h>
-#include <netdb.h>
-#include <netinet/in.h>
 #include <pthread.h>
 #include <pwd.h>
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
-#include <sys/socket.h>
 #include <unistd.h>
 
 #ifdef LIBSSH2_USES_GCRYPT
@@ -414,81 +411,10 @@ guac_common_ssh_session* guac_common_ssh_create_session(guac_client* client,
         int keepalive, const char* host_key,
         guac_ssh_credential_handler* credential_handler) {
 
-    int retval;
-
-    int fd;
-    struct addrinfo* addresses;
-    struct addrinfo* current_address;
-
-    char connected_address[1024];
-    char connected_port[64];
-
-    struct addrinfo hints = {
-        .ai_family   = AF_UNSPEC,
-        .ai_socktype = SOCK_STREAM,
-        .ai_protocol = IPPROTO_TCP
-    };
-
-    /* Get addresses connection */
-    if ((retval = getaddrinfo(hostname, port, &hints, &addresses))) {
+    int fd = guac_socket_tcp_connect(hostname, port);
+    if (fd < 0) {
         guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
-                "Error parsing given address or port: %s",
-                gai_strerror(retval));
-        return NULL;
-    }
-
-    /* Attempt connection to each address until success */
-    current_address = addresses;
-    while (current_address != NULL) {
-
-        /* Resolve hostname */
-        if ((retval = getnameinfo(current_address->ai_addr,
-                current_address->ai_addrlen,
-                connected_address, sizeof(connected_address),
-                connected_port, sizeof(connected_port),
-                NI_NUMERICHOST | NI_NUMERICSERV)))
-            guac_client_log(client, GUAC_LOG_DEBUG,
-                    "Unable to resolve host: %s", gai_strerror(retval));
-
-        /* Get socket */
-        fd = socket(current_address->ai_family, SOCK_STREAM, 0);
-        if (fd < 0) {
-            guac_client_abort(client, GUAC_PROTOCOL_STATUS_SERVER_ERROR,
-                    "Unable to create socket: %s", strerror(errno));
-            freeaddrinfo(addresses);
-            return NULL;
-        }
-
-        /* Connect */
-        if (connect(fd, current_address->ai_addr,
-                        current_address->ai_addrlen) == 0) {
-
-            guac_client_log(client, GUAC_LOG_DEBUG,
-                    "Successfully connected to host %s, port %s",
-                    connected_address, connected_port);
-
-            /* Done if successful connect */
-            break;
-
-        }
-
-        /* Otherwise log information regarding bind failure */
-        guac_client_log(client, GUAC_LOG_DEBUG, "Unable to connect to "
-                "host %s, port %s: %s",
-                connected_address, connected_port, strerror(errno));
-
-        close(fd);
-        current_address = current_address->ai_next;
-
-    }
-
-    /* Free addrinfo */
-    freeaddrinfo(addresses);
-
-    /* If unable to connect to anything, fail */
-    if (current_address == NULL) {
-        guac_client_abort(client, GUAC_PROTOCOL_STATUS_UPSTREAM_NOT_FOUND,
-                "Unable to connect to any addresses.");
+            "Failed to open TCP connection to %s on %s.", hostname, port);
         return NULL;
     }
 

src/libguac/Makefile.am

@@ -70,6 +70,7 @@ libguacinc_HEADERS =                  \
     guacamole/socket-constants.h      \
     guacamole/socket.h                \
     guacamole/socket-fntypes.h        \
+    guacamole/socket-tcp.h            \
     guacamole/socket-types.h          \
     guacamole/stream.h                \
     guacamole/stream-types.h          \
@@ -128,6 +129,7 @@ libguac_la_SOURCES =   \
     socket-broadcast.c \
     socket-fd.c        \
     socket-nest.c      \
+    socket-tcp.c       \
     socket-tee.c       \
     string.c           \
     timestamp.c        \

src/libguac/guacamole/socket-tcp.h

@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#ifndef __GUAC_SOCKET_TCP_H
+#define __GUAC_SOCKET_TCP_H
+
+#include "config.h"
+
+#include <stddef.h>
+
+/**
+ * Given a hostname or IP address and port, attempt to connect to that
+ * system, returning an open socket if the connection succeeds, or a negative
+ * value if it fails. If it fails the errno variable will be set.
+ *
+ * @param hostname
+ *     The hostname or IP address to which to attempt connections.
+ *
+ * @param port
+ *     The TCP port to which to attempt to connect.
+ *
+ * @return
+ *     A valid socket if the connection succeeds, or a negative integer if it
+ *     fails.
+ */
+int guac_socket_tcp_connect(const char* hostname, const char* port);
+
+#endif // __GUAC_SOCKET_TCP_H

src/libguac/guacamole/string.h

@@ -29,6 +29,24 @@
 #include <stddef.h>
 #include <string.h>
 
+/**
+ * Convert the provided unsigned integer into a string, returning the number of
+ * characters written into the destination string, or a negative value if an
+ * error occurs.
+ *
+ * @param dest
+ *     The destination string to copy the data into, which should already be
+ *     allocated and at a size that can handle the string representation of the
+ *     inteer.
+ *
+ * @param integer
+ *     The unsigned integer to convert to a string.
+ * 
+ * @return
+ *     The number of characters written into the dest string.
+ */
+int guac_itoa(char* restrict dest, unsigned int integer);
+
 /**
  * Copies a limited number of bytes from the given source string to the given
  * destination buffer. The resulting buffer will always be null-terminated,

src/libguac/guacamole/wol-constants.h

@@ -27,6 +27,12 @@
  * @file wol-constants.h
  */
 
+/**
+ * The default number of times to retry a connection to a server after waking
+ * the server with a WOL packet before giving up.
+ */
+#define GUAC_WOL_DEFAULT_CONNECT_RETRIES 5
+
 /**
  * The value for the local IPv4 broadcast address.
  */

src/libguac/guacamole/wol.h

@@ -52,5 +52,45 @@
 int guac_wol_wake(const char* mac_addr, const char* broadcast_addr,
         const unsigned short udp_port);
 
+/**
+ * Send the wake-up packet to the specified destination, returning zero if the
+ * wake was sent successfully, or non-zero if an error occurs sending the
+ * wake packet.  Note that the return value does not specify whether the
+ * system actually wakes up successfully, only whether or not the packet
+ * is transmitted.
+ * 
+ * @param mac_addr
+ *     The MAC address to place in the magic Wake-on-LAN packet.
+ * 
+ * @param broadcast_addr
+ *     The broadcast address to which to send the magic Wake-on-LAN packet.
+ * 
+ * @param udp_port
+ *     The UDP port to use when sending the WoL packet.
+ *
+ * @param wait_time
+ *     The number of seconds to wait between connection attempts after the WOL
+ *     packet has been sent.
+ *
+ * @param retries
+ *     The number of attempts to make to connect to the system before giving up
+ *     on the connection.
+ *
+ * @param hostname
+ *     The hostname or IP address of the system that has been woken up and to
+ *     to which the connection will be attempted.
+ *
+ * @param port
+ *     The TCP port of the remote system on which the connection will be
+ *     attempted after the system has been woken.
+ * 
+ * @return 
+ *     Zero if the packet is successfully sent to the destination; non-zero
+ *     if the packet cannot be sent.
+ */
+int guac_wol_wake_and_wait(const char* mac_addr, const char* broadcast_addr,
+        const unsigned short udp_port, int wait_time, int retries,
+        const char* hostname, const char* port);
+
 #endif /* GUAC_WOL_H */
 

src/libguac/socket-tcp.c

@@ -0,0 +1,102 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include "config.h"
+#include "guacamole/error.h"
+#include "guacamole/socket.h"
+
+#include <errno.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <sys/socket.h>
+
+int guac_socket_tcp_connect(const char* hostname, const char* port) {
+
+    int retval;
+
+    int fd = EBADFD;
+    struct addrinfo* addresses;
+    struct addrinfo* current_address;
+
+    char connected_address[1024];
+    char connected_port[64];
+
+    struct addrinfo hints = {
+        .ai_family   = AF_UNSPEC,
+        .ai_socktype = SOCK_STREAM,
+        .ai_protocol = IPPROTO_TCP
+    };
+
+    /* Get addresses for requested hostname and port. */
+    if ((retval = getaddrinfo(hostname, port, &hints, &addresses))) {
+        guac_error = GUAC_STATUS_INVALID_ARGUMENT;
+        guac_error_message = "Error parsing address or port.";
+        return retval;
+    }
+
+    /* Attempt connection to each address until success */
+    current_address = addresses;
+    while (current_address != NULL) {
+
+        /* Resolve hostname */
+        if ((retval = getnameinfo(current_address->ai_addr,
+                current_address->ai_addrlen,
+                connected_address, sizeof(connected_address),
+                connected_port, sizeof(connected_port),
+                NI_NUMERICHOST | NI_NUMERICSERV))) {
+
+            guac_error = GUAC_STATUS_INVALID_ARGUMENT;
+            guac_error_message = "Error resolving host.";
+            continue;
+        }
+
+        /* Get socket */
+        fd = socket(current_address->ai_family, SOCK_STREAM, 0);
+        if (fd < 0) {
+            freeaddrinfo(addresses);
+            return fd;
+        }
+
+        /* Connect */
+        if (connect(fd, current_address->ai_addr,
+                        current_address->ai_addrlen) == 0) {
+
+            /* Done if successful connect */
+            break;
+
+        }
+
+        close(fd);
+        current_address = current_address->ai_next;
+
+    }
+
+    /* Free addrinfo */
+    freeaddrinfo(addresses);
+
+    /* If unable to connect to anything, set error status. */
+    if (current_address == NULL) {
+        guac_error = GUAC_STATUS_REFUSED;
+        guac_error_message = "Unable to connect to remote host.";
+    }
+
+    /* Return the fd, or the error message if the socket connection failed. */
+    return fd;
+
+}

src/libguac/string.c

@@ -22,6 +22,7 @@
 #include "guacamole/mem.h"
 
 #include <stddef.h>
+#include <stdio.h>
 #include <string.h>
 
 /**
@@ -44,6 +45,20 @@
  */
 #define REMAINING(n, length) (((n) < (length)) ? 0 : ((n) - (length)))
 
+int guac_itoa(char* restrict dest, unsigned int integer) {
+
+    /* Determine size of string. */
+    int str_size = snprintf(dest, 0, "%i", integer);
+
+    /* If an error occurs, just return that and skip the conversion. */
+    if (str_size < 0)
+        return str_size;
+
+    /* Do the conversion and return. */
+    return snprintf(dest, (str_size + 1), "%i", integer);
+
+}
+
 size_t guac_strlcpy(char* restrict dest, const char* restrict src, size_t n) {
 
 #ifdef HAVE_STRLCPY