2 files changed, 13 insertions, 8 deletions

diff --git a/plugins/sslutils.c b/plugins/sslutils.c
index f5035e23..afc24be1 100644
--- a/plugins/sslutils.c
+++ b/plugins/sslutils.c
@@ -30,6 +30,10 @@
 #include "common.h"
 #include "netutils.h"
 
+/* Max length of timestamps, ex: "03/05/2009 00:13 GMT". Calculate up to 6
+ * chars for the timezone (ex: "GMT-10") and one terminating \0 */
+#define TS_LENGTH 24
+
 #ifdef HAVE_SSL
 static SSL_CTX *c=NULL;
 static SSL *s=NULL;
@@ -90,7 +94,7 @@ int np_net_ssl_check_cert(int days_till_exp){
         int offset;
         struct tm stamp;
         int days_left;
-        char timestamp[17] = "";
+        char timestamp[TS_LENGTH] = "";
 
         certificate=SSL_get_peer_certificate(s);
         if(! certificate){
@@ -135,16 +139,17 @@ int np_net_ssl_check_cert(int days_till_exp){
         stamp.tm_sec = 0;
         stamp.tm_isdst = -1;
 
-        days_left = (mktime (&stamp) - time (NULL)) / 86400;
+        float time_left = difftime(timegm(&stamp), time(NULL));
+        days_left = time_left / 86400;
         snprintf
-                (timestamp, 17, "%02d/%02d/%04d %02d:%02d",
+                (timestamp, TS_LENGTH, "%02d/%02d/%04d %02d:%02d %s",
                  stamp.tm_mon + 1,
-                 stamp.tm_mday, stamp.tm_year + 1900, stamp.tm_hour, stamp.tm_min);
+                 stamp.tm_mday, stamp.tm_year + 1900, stamp.tm_hour, stamp.tm_min, stamp.tm_zone);
 
         if (days_left > 0 && days_left <= days_till_exp) {
                 printf (_("WARNING - Certificate expires in %d day(s) (%s).\n"), days_left, timestamp);
                 return STATE_WARNING;
-        } else if (days_left < 0) {
+        } else if (time_left < 0) {
                 printf (_("CRITICAL - Certificate expired on %s.\n"), timestamp);
                 return STATE_CRITICAL;
         } else if (days_left == 0) {
diff --git a/plugins/tests/check_http.t b/plugins/tests/check_http.t
index d7f4148c..0a1b0bc8 100755
--- a/plugins/tests/check_http.t
+++ b/plugins/tests/check_http.t
@@ -163,18 +163,18 @@ SKIP: {
         
         $result = NPTest->testCmd( "$command -p $port_https -S -C 14" );
         is( $result->return_code, 0, "$command -p $port_https -S -C 14" );
-        is( $result->output, 'OK - Certificate will expire on 03/03/2019 21:41.', "output ok" );
+        is( $result->output, 'OK - Certificate will expire on 03/03/2019 21:41 GMT.', "output ok" );
 
         $result = NPTest->testCmd( "$command -p $port_https -S -C 14000" );
         is( $result->return_code, 1, "$command -p $port_https -S -C 14000" );
-        like( $result->output, '/WARNING - Certificate expires in \d+ day\(s\) \(03/03/2019 21:41\)./', "output ok" );
+        like( $result->output, '/WARNING - Certificate expires in \d+ day\(s\) \(03/03/2019 21:41 GMT\)./', "output ok" );
 
 
         # Expired cert tests
         $result = NPTest->testCmd( "$command -p $port_https_expired -S -C 7" );
         is( $result->return_code, 2, "$command -p $port_https_expired -S -C 7" );
         is( $result->output, 
-                'CRITICAL - Certificate expired on 03/05/2009 00:13.',
+                'CRITICAL - Certificate expired on 03/05/2009 00:13 GMT.',
                 "output ok" );
 
 }