New option to check_smtp to ignore failures when sending QUIT (#3358348 - Duncan Ferguson)

2 files changed, 27 insertions, 4 deletions

diff --git a/NEWS b/NEWS
index 8bb0fcb2..9ff87554 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ This file documents the major additions and syntax changes between releases.
         check_http now uses standard threshold functions (enables floating point and ranges)
         check_http now checks for and prints the certificate cn (hostname) in SSL certificate checks (Stéphane Urbanovski)
         Add perfdata to check_ssh (#3244097 - Marco Beck)
+        New option to check_smtp to ignore failures when sending QUIT (#3358348 - Duncan Ferguson)
 
         FIXES
         Fix check_disk free space calculation if blocksizes differ within a disk group (Bekar - #2973603)
diff --git a/plugins/check_smtp.c b/plugins/check_smtp.c
index ed491638..6c5994c0 100644
--- a/plugins/check_smtp.c
+++ b/plugins/check_smtp.c
@@ -114,6 +114,7 @@ enum {
   TCP_PROTOCOL = 1,
   UDP_PROTOCOL = 2,
 };
+int ignore_send_quit_failure = FALSE;
 
 
 int
@@ -129,6 +130,9 @@ main (int argc, char **argv)
         char *error_msg = "";
         struct timeval tv;
 
+        /* Catch pipe errors in read/write - sometimes occurs when writing QUIT */
+        (void) signal (SIGPIPE, SIG_IGN);
+
         setlocale (LC_ALL, "");
         bindtextdomain (PACKAGE, LOCALEDIR);
         textdomain (PACKAGE);
@@ -476,6 +480,7 @@ process_arguments (int argc, char **argv)
                 {"help", no_argument, 0, 'h'},
                 {"starttls",no_argument,0,'S'},
                 {"certificate",required_argument,0,'D'},
+                {"ignore-quit-failure",no_argument,0,'q'},
                 {0, 0, 0, 0}
         };
 
@@ -492,7 +497,7 @@ process_arguments (int argc, char **argv)
         }
 
         while (1) {
-                c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:SD:F:A:U:P:",
+                c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:SD:F:A:U:P:q",
                                  longopts, &option);
 
                 if (c == -1 || c == EOF)
@@ -579,6 +584,9 @@ process_arguments (int argc, char **argv)
                 case 'v':                                                                       /* verbose */
                         verbose++;
                         break;
+                case 'q':
+                        ignore_send_quit_failure++;             /* ignore problem sending QUIT */
+                        break;
                 case 't':                                                                       /* timeout */
                         if (is_intnonneg (optarg)) {
                                 socket_timeout = atoi (optarg);
@@ -662,8 +670,20 @@ void
 smtp_quit(void)
 {
         int bytes;
+        int n;
+
+        n = my_send(SMTP_QUIT, strlen(SMTP_QUIT));
+        if(n < 0) {
+                if(ignore_send_quit_failure) {
+                        if(verbose) {
+                                printf(_("Connection closed by server before sending QUIT command\n"));
+                        }
+                        return;
+                }
+                die (STATE_UNKNOWN,
+                        _("Connection closed by server before sending QUIT command\n"));
+        }
 
-        my_send(SMTP_QUIT, strlen(SMTP_QUIT));
         if (verbose)
                 printf(_("sent %s\n"), "QUIT");
 
@@ -797,7 +817,9 @@ print_help (void)
   printf ("    %s\n", _("SMTP AUTH username"));
   printf (" %s\n", "-P, --authpass=STRING");
   printf ("    %s\n", _("SMTP AUTH password"));
-
+  printf (" %s\n", "-q, --ignore-quit-failure");
+  printf ("    %s\n", _("Ignore failure when sending QUIT command to server"));
+   
         printf (UT_WARN_CRIT);
 
         printf (UT_TIMEOUT, DEFAULT_SOCKET_TIMEOUT);
@@ -821,6 +843,6 @@ print_usage (void)
   printf ("%s\n", _("Usage:"));
   printf ("%s -H host [-p port] [-e expect] [-C command] [-f from addr]", progname);
   printf ("[-A authtype -U authuser -P authpass] [-w warn] [-c crit] [-t timeout]\n");
-  printf ("[-F fqdn] [-S] [-D days] [-v] [-4|-6]\n");
+  printf ("[-F fqdn] [-S] [-D days] [-v] [-4|-6] [-q]\n");
 }