[PATCH v28 5/7] server: Introduce error when attempting to connect() to abstract AF_UNIX sockets.

[Ally Sommers]

From: Ally Sommers

This also introduces an error when attempting to create an AF_UNIX
socket of type SOCK_DGRAM.
---
 server/sock.c | 31 ++++++++++++++++++++++++-------
 1 file changed, 24 insertions(+), 7 deletions(-)

diff --git a/server/sock.c b/server/sock.c
index 8378944b482..f801b44240a 100644
--- a/server/sock.c
+++ b/server/sock.c
@@ -1881,6 +1881,12 @@ static int init_socket( struct sock *sock, int family, int type, int protocol )
         return -1;
     }

+    if (unix_family == AF_UNIX && unix_type == SOCK_DGRAM)
+    {
+        set_win32_error(WSAEAFNOSUPPORT);
+        return -1;
+    }
+
     sockfd = socket( unix_family, unix_type, unix_protocol );

#ifdef linux
@@ -2639,17 +2645,28 @@ static void sock_ioctl( struct fd *fd, ioctl_code_t code, struct async *async )
         if (unix_addr.addr.sa_family == AF_INET && !memcmp( &unix_addr.in.sin_addr, magic_loopback_addr, 4 ))
             unix_addr.in.sin_addr.s_addr = htonl( INADDR_LOOPBACK );

-        if (sock->family == WS_AF_UNIX && *((struct WS_sockaddr_un *)&addr)->sun_path)
+        if (sock->family == WS_AF_UNIX)
         {
-            char *unix_path = (char *)(params + 1) + params->addr_len;
-            char unix_path_copy[PATH_MAX];
-            strcpy(unix_path_copy, unix_path);
-            if (chdir( dirname( unix_path_copy ) ) == -1)
+            if (*((struct WS_sockaddr_un *)&addr)->sun_path)
             {
-                set_error( sock_get_ntstatus( errno ) );
+                char *unix_path = (char *)(params + 1) + params->addr_len;
+                char unix_path_copy[PATH_MAX];
+                strcpy(unix_path_copy, unix_path);
+                if (chdir( dirname( unix_path_copy ) ) == -1)
+                {
+                    set_error( sock_get_ntstatus( errno ) );
+                    return;
+                }
+                memcpy( unix_addr.un.sun_path, basename( unix_path ), sizeof(unix_addr.un.sun_path) );
+            }
+            else
+            {
+                /* Contrary to documentation, Windows does not currently support abstract Unix
+                 * sockets. connect() throws WSAEINVAL if sun_family is AF_UNIX and sun_path
+                 * begins with '\0', even though bind() will succeed. */
+                set_win32_error( WSAEINVAL );
                 return;
             }
-            memcpy( unix_addr.un.sun_path, basename( unix_path ), sizeof(unix_addr.un.sun_path) );
         }

ret = connect( unix_fd, &unix_addr.addr, unix_len );