fix help option not exit problem

[KaliAssistant]

🩹 Fix: Exit immediately after showing help (-h or --help)

🐛 Problem

When running:

yersinia -h

The program prints help but continues execution, which leads to:

./yersinia -h cdp
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����۱������۰�����               Yersinia...                                     
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۲���۱���������۰���۲��         The Black Death for nowadays networks             
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 ��۰���۱�����������۰��۲�             by Slay & tomac                            
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     ��۲�۱�������������۰����        http://www.yersinia.net                     
      ۲����۱�������������۲۲            yersinia@yersinia.net                    
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         �۲�۰������۱�۰����     Prune your MSTP, RSTP, STP trees!!!!             
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Usage: yersinia [-hVGIDd] [-l logfile] [-c conffile] protocol [protocol_options]
       -V   Program version.
       -h   This help screen.
       -G   Graphical mode (GTK).
       -I   Interactive mode (ncurses).
       -D   Daemon mode.
       -d   Debug.
       -l logfile   Select logfile.
       -c conffile  Select config file.
  protocol   One of the following: cdp, dhcp, dot1q, dot1x, dtp, hsrp, isl, mpls, stp, vtp.

Try 'yersinia protocol -h' to see protocol_options help

Please, see the man page for a full list of options and many examples.
Send your bugs & suggestions to the Yersinia developers <yersinia@yersinia.net>

^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^C^X^X^Z^Z^X^H^G^K, (not exit, Ctrl^C not working)

This is because parser_initial() returned 0 even after displaying help, instead of exiting cleanly.

parser.c:204:12 : return non <0 here
    return 0;
    ~~~~~~~^
 
yersinia.c:201:55: will clean_exit when parser_initial return < 0
   if (parser_initial(tty_tmp, cl_args, argc, argv) < 0) {
                                              ~~~~~~~~^
      clean_exit();
      ~~~~ ^ ~~~~

✅ Solution

Return -1 from parser_initial() when help is invoked to signal main() to terminate early via clean_exit().

🔧 Patch

diff --git a/src/parser.c b/src/parser.c
index f3912c3..ca35edc 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -103,7 +103,7 @@ parser_initial(struct term_tty *tty, struct cl_args *cl_args, int argc, char **a
        if (!strcmp(argv[i],"-h") || !strcmp(argv[i],"--help"))
        {
           parser_help();
-          break;
+          return -1;
        }
        else
        if (!strcmp(argv[i],"-V") || !strcmp(argv[i],"--Version"))

🧪 Tested

• ✅ yersinia -h prints help and exits without error.
• ✅ Normal protocol execution (e.g. yersinia stp -attack 0 ...) works correctly.