make the exec (-e) an optional feature of netcat

git-svn-id: svn://busybox.net/trunk/busybox@10254 69ca8d6d-28ef-0310-b511-8ec308f3f277

3 files changed, 28 insertions, 18 deletions

diff --git a/include/usage.h b/include/usage.h
index d731957f1..1ef79df61 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -1824,6 +1824,11 @@
         " or\n" \
         "$ nameif -c /etc/my_mactab_file\n" \
 
+#ifdef CONFIG_NC_GAPING_SECURITY_HOLE
+#  define USAGE_NC_EXEC(a) a
+#else
+#  define USAGE_NC_EXEC(a)
+#endif
 #define nc_trivial_usage \
         "[OPTIONS] [IP] [port]"
 #define nc_full_usage \
@@ -1832,8 +1837,10 @@
         "\t-l\t\tlisten mode, for inbound connects\n" \
         "\t-p PORT\t\tlocal port number\n" \
         "\t-i SECS\t\tdelay interval for lines sent\n" \
-        "\t-w SECS\t\ttimeout for connects and final net reads\n" \
-        "\t-e PROG\t\tprogram to exec after connect (dangerous!)"
+        USAGE_NC_EXEC( \
+        "\t-e PROG\t\tprogram to exec after connect (dangerous!)\n" \
+        ) \
+        "\t-w SECS\t\ttimeout for connects and final net reads"
 #define nc_example_usage \
         "$ nc foobar.somedomain.com 25\n" \
         "220 foobar ESMTP Exim 3.12 #1 Sat, 15 Apr 2000 00:03:02 -0600\n" \
diff --git a/networking/Config.in b/networking/Config.in
index 418ef4bc4..a84427981 100644
--- a/networking/Config.in
+++ b/networking/Config.in
@@ -422,6 +422,14 @@ config CONFIG_NC
           A simple Unix utility which reads and writes data across network
           connections.
 
+config CONFIG_NC_GAPING_SECURITY_HOLE
+        bool "gaping security hole"
+        default n
+        depends on CONFIG_NC
+        help
+          Add support for executing a program after making or receiving a
+          successful connection (-e option).
+
 config CONFIG_NETSTAT
         bool "netstat"
         default n
diff --git a/networking/nc.c b/networking/nc.c
index bbcbc0d13..bb6373fd3 100644
--- a/networking/nc.c
+++ b/networking/nc.c
@@ -4,7 +4,7 @@
 
     0.0.1   6K      It works.
     0.0.2   5K      Smaller and you can also check the exit condition if you wish.
-    0.0.3           Uses select()
+    0.0.3           Uses select()
 
     19980918 Busy Boxed! Dave Cinege
     19990512 Uses Select. Charles P. Wright
@@ -23,7 +23,6 @@
     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
 */
 
 #include <stdio.h>
@@ -41,8 +40,6 @@
 #include <sys/ioctl.h>
 #include "busybox.h"
 
-#define GAPING_SECURITY_HOLE
-
 static void timeout(int signum)
 {
         bb_error_msg_and_die("Timed out");
@@ -52,8 +49,8 @@ int nc_main(int argc, char **argv)
 {
         int do_listen = 0, lport = 0, delay = 0, wsecs = 0, tmpfd, opt, sfd, x;
         char buf[BUFSIZ];
-#ifdef GAPING_SECURITY_HOLE
-        char * pr00gie = NULL;
+#ifdef CONFIG_NC_GAPING_SECURITY_HOLE
+        char *pr00gie = NULL;
 #endif
 
         struct sockaddr_in address;
@@ -72,7 +69,7 @@ int nc_main(int argc, char **argv)
                         case 'i':
                                 delay = atoi(optarg);
                                 break;
-#ifdef GAPING_SECURITY_HOLE
+#ifdef CONFIG_NC_GAPING_SECURITY_HOLE
                         case 'e':
                                 pr00gie = optarg;
                                 break;
@@ -85,13 +82,12 @@ int nc_main(int argc, char **argv)
                 }
         }
 
-#ifdef GAPING_SECURITY_HOLE
+#ifdef CONFIG_NC_GAPING_SECURITY_HOLE
         if (pr00gie) {
                 /* won't need stdin */
                 close (STDIN_FILENO);      
         }
-#endif /* GAPING_SECURITY_HOLE */
-
+#endif /* CONFIG_NC_GAPING_SECURITY_HOLE */
 
         if ((do_listen && optind != argc) || (!do_listen && optind + 2 != argc))
                 bb_show_usage();
@@ -142,19 +138,18 @@ int nc_main(int argc, char **argv)
                 signal(SIGALRM, SIG_DFL);
         }
 
-#ifdef GAPING_SECURITY_HOLE
+#ifdef CONFIG_NC_GAPING_SECURITY_HOLE
         /* -e given? */
         if (pr00gie) {
                 dup2(sfd, 0);
                 close(sfd);
-                dup2 (0, 1);
-                dup2 (0, 2);
-                execl (pr00gie, pr00gie, NULL);
+                dup2(0, 1);
+                dup2(0, 2);
+                execl(pr00gie, pr00gie, NULL);
                 /* Don't print stuff or it will go over the wire.... */
                 _exit(-1);
         }
-#endif /* GAPING_SECURITY_HOLE */
-
+#endif /* CONFIG_NC_GAPING_SECURITY_HOLE */
 
         FD_ZERO(&readfds);
         FD_SET(sfd, &readfds);