Customize 'permission denied' error.

From: Jan Safranek <jsafrane@redhat.com>

Add Fedora-specific message to error output when dumpcap cannot be started

because of permissions.

Signed-off-by: Jan Safranek <jsafrane@redhat.com>

---

 capture_sync.c |   14 ++++++++++----

 1 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/capture_sync.c b/capture_sync.c

index 68b79f7..71de366 100644

--- a/capture_sync.c

+++ b/capture_sync.c

@@ -351,6 +351,7 @@ sync_pipe_start(capture_options *capture_opts) {

     gchar *signal_pipe_name;

 #else

     char errmsg[1024+1];

+    const char *securitymsg = "";

     int sync_pipe[2];                       /* pipe used to send messages from child to parent */

     enum PIPES { PIPE_READ, PIPE_WRITE };   /* Constants 0 and 1 for PIPE_READ and PIPE_WRITE */

 #endif

@@ -596,8 +597,10 @@ sync_pipe_start(capture_options *capture_opts) {

       dup2(sync_pipe[PIPE_WRITE], 2);

       ws_close(sync_pipe[PIPE_READ]);

       execv(argv[0], (gpointer)argv);

-      g_snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s",

-                argv[0], strerror(errno));

+      if (errno == EPERM || errno == EACCES)

+          securitymsg = "\nAre you memeber of 'wireshark' group? Try running 'usermod -a -G wireshark <username>' as root.";

+      g_snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s%s",

+                argv[0], strerror(errno), securitymsg);

       sync_pipe_errmsg_to_parent(2, errmsg, "");

       /* Exit with "_exit()", so that we don't close the connection

@@ -687,6 +690,7 @@ sync_pipe_open_command(const char** argv, int *data_read_fd,

     int i;

 #else

     char errmsg[1024+1];

+    const char *securitymsg = "";

     int sync_pipe[2];                       /* pipe used to send messages from child to parent */

     int data_pipe[2];                       /* pipe used to send data from child to parent */

 #endif

@@ -811,8 +815,10 @@ sync_pipe_open_command(const char** argv, int *data_read_fd,

         ws_close(sync_pipe[PIPE_READ]);

         ws_close(sync_pipe[PIPE_WRITE]);

         execv(argv[0], (gpointer)argv);

-        g_snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s",

-                   argv[0], strerror(errno));

+        if (errno == EPERM || errno == EACCES)

+            securitymsg = "\nAre you memeber of 'wireshark' group? Try running 'usermod -a -G wireshark <username>' as root.";

+        g_snprintf(errmsg, sizeof errmsg, "Couldn't run %s in child process: %s%s",

+                   argv[0], strerror(errno), securitymsg);

         sync_pipe_errmsg_to_parent(2, errmsg, "");

         /* Exit with "_exit()", so that we don't close the connection