extcap: Create unique pipe names for each interface

On Windows the pipe names does not get random characters appended.
Add the interface name and pipe type to make it unique.

This partly fixes the issue with capturing from multiple extcap
interfaces on Windows.

Ping-Bug: 13653
Ping-Bug: 13833
Change-Id: I4290b37cf789bf77608993682a803aca29513d28
Reviewed-on: https://code.wireshark.org/review/23158
Petri-Dish: Stig Bjørlykke <stig@bjorlykke.org>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 22 insertions, 22 deletions

diff --git a/extcap.c b/extcap.c
index 9bb36c178b..d025c9fe25 100644
--- a/extcap.c
+++ b/extcap.c
@@ -63,7 +63,7 @@
 #include "extcap_spawn.h"
 
 #ifdef _WIN32
-static HANDLE pipe_h = NULL;
+static HANDLE pipe_h = INVALID_HANDLE_VALUE;
 #endif
 
 static void extcap_child_watch_cb(GPid pid, gint status, gpointer user_data);
@@ -1032,13 +1032,14 @@ void extcap_if_cleanup(capture_options *capture_opts, gchar **errormsg)
               "Extcap [%s] - Cleaning up fifo: %s; PID: %d", interface_opts.name,
               interface_opts.extcap_fifo, interface_opts.extcap_pid);
 #ifdef _WIN32
-        if (pipe_h)
+        if (interface_opts.extcap_pipe_h != INVALID_HANDLE_VALUE)
         {
             g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_DEBUG,
                   "Extcap [%s] - Closing pipe", interface_opts.name);
-            FlushFileBuffers(pipe_h);
-            DisconnectNamedPipe(pipe_h);
-            CloseHandle(pipe_h);
+            FlushFileBuffers(interface_opts.extcap_pipe_h);
+            DisconnectNamedPipe(interface_opts.extcap_pipe_h);
+            CloseHandle(interface_opts.extcap_pipe_h);
+            interface_opts.extcap_pipe_h = INVALID_HANDLE_VALUE;
         }
 #else
         if (interface_opts.extcap_fifo != NULL && file_exists(interface_opts.extcap_fifo))
@@ -1353,15 +1354,21 @@ extcap_init_interfaces(capture_options *capture_opts)
         /* create control pipes if having toolbar */
         if (extcap_has_toolbar(interface_opts.name))
         {
-            extcap_create_pipe(&interface_opts.extcap_control_in);
-            extcap_create_pipe(&interface_opts.extcap_control_out);
+            extcap_create_pipe(interface_opts.name, &interface_opts.extcap_control_in,
+                               EXTCAP_CONTROL_IN_PREFIX);
+            extcap_create_pipe(interface_opts.name, &interface_opts.extcap_control_out,
+                               EXTCAP_CONTROL_OUT_PREFIX);
         }
 
         /* create pipe for fifo */
-        if (!extcap_create_pipe(&interface_opts.extcap_fifo))
+        if (!extcap_create_pipe(interface_opts.name, &interface_opts.extcap_fifo,
+                                EXTCAP_PIPE_PREFIX))
         {
             return FALSE;
         }
+#ifdef _WIN32
+        interface_opts.extcap_pipe_h = pipe_h;
+#endif
 
         /* Create extcap call */
         args = extcap_prepare_arguments(interface_opts);
@@ -1396,9 +1403,8 @@ extcap_init_interfaces(capture_options *capture_opts)
          */
         if (pid != INVALID_EXTCAP_PID)
         {
-            extcap_wait_for_pipe(pipe_h, pid);
+            extcap_wait_for_pipe(interface_opts.extcap_pipe_h, pid);
         }
-
 #endif
 
         interface_opts.extcap_userdata = (gpointer) userdata;
@@ -1410,16 +1416,7 @@ extcap_init_interfaces(capture_options *capture_opts)
     return TRUE;
 }
 
-#ifdef _WIN32
-/* called by capture_sync to get the CreatNamedPipe handle*/
-HANDLE
-extcap_get_win32_handle()
-{
-    return pipe_h;
-}
-#endif
-
-gboolean extcap_create_pipe(char **fifo)
+gboolean extcap_create_pipe(const gchar *ifname, gchar **fifo, const gchar *pipe_prefix)
 {
 #ifdef _WIN32
     gchar timestr[ 14 + 1 ];
@@ -1435,7 +1432,7 @@ gboolean extcap_create_pipe(char **fifo)
      * so we won't get a null pointer back from localtime().
      */
     strftime(timestr, sizeof(timestr), "%Y%m%d%H%M%S", localtime(&current_time));
-    pipename = g_strconcat("\\\\.\\pipe\\", EXTCAP_PIPE_PREFIX, "_", timestr, NULL);
+    pipename = g_strconcat("\\\\.\\pipe\\", pipe_prefix, "_", ifname, "_", timestr, NULL);
 
     /* Security struct to enable Inheritable HANDLE */
     memset(&security, 0, sizeof(SECURITY_ATTRIBUTES));
@@ -1466,10 +1463,13 @@ gboolean extcap_create_pipe(char **fifo)
     gchar *temp_name = NULL;
     int fd = 0;
 
-    if ((fd = create_tempfile(&temp_name, EXTCAP_PIPE_PREFIX, NULL)) < 0)
+    gchar *pfx = g_strconcat(pipe_prefix, "_", ifname, NULL);
+    if ((fd = create_tempfile(&temp_name, pfx, NULL)) < 0)
     {
+        g_free(pfx);
         return FALSE;
     }
+    g_free(pfx);
 
     ws_close(fd);