Add hardware timestamping support

pcap provides a pcap_set_tstamp_type function, which can be used to request
hardware timestamps from a supporting kernel.

This patch adds support for aforementioned function as well as two new
command line options to dumpcap, wireshark and tshark:

    --list-time-stamp-types
                             List time stamp types supported for the interface
    --time-stamp-type <type>
                             Change the interface's timestamp method

Name choice mimics those used by tcpdump(1), which already supports this
feature. However, unlike tcpdump, we provide both options unconditionally.
If Wireshark was configured without pcap_set_tstamp_type being available,
--list-time-stamp-types reports an empty list.

Change-Id: I418a4b2b84cb01949cd262aad0ad8427f5ac0652
Signed-off-by: Ahmad Fatoum <ahmad.fatoum@siemens.com>
Reviewed-on: https://code.wireshark.org/review/23113
Petri-Dish: Guy Harris <guy@alum.mit.edu>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 29 insertions, 8 deletions

diff --git a/tshark.c b/tshark.c
index 5c44d64e27..97b78b5a58 100644
--- a/tshark.c
+++ b/tshark.c
@@ -148,6 +148,7 @@
 #define INVALID_CAPABILITY 2
 #define INVALID_TAP 2
 #define INVALID_DATA_LINK 2
+#define INVALID_TIMESTAMP_TYPE 2
 #define INVALID_CAPTURE 2
 #define INIT_FAILED 2
 
@@ -353,8 +354,10 @@ print_usage(FILE *output)
   fprintf(output, "  -B <buffer size>         size of kernel buffer (def: %dMB)\n", DEFAULT_CAPTURE_BUFFER_SIZE);
 #endif
   fprintf(output, "  -y <link type>           link layer type (def: first appropriate)\n");
+  fprintf(output, "  --time-stamp-type <type> timestamp method for interface\n");
   fprintf(output, "  -D                       print list of interfaces and exit\n");
   fprintf(output, "  -L                       print list of link-layer types of iface and exit\n");
+  fprintf(output, "  --list-time-stamp-types  print list of timestamp types for iface and exit\n");
   fprintf(output, "\n");
   fprintf(output, "Capture stop conditions:\n");
   fprintf(output, "  -c <packet count>        stop after n packets (def: infinite)\n");
@@ -686,7 +689,7 @@ main(int argc, char *argv[])
   volatile gboolean    success;
   volatile int         exit_status = EXIT_SUCCESS;
 #ifdef HAVE_LIBPCAP
-  gboolean             list_link_layer_types = FALSE;
+  int                  caps_queries = 0;
   gboolean             start_capture = FALSE;
   GList               *if_list;
   gchar               *err_str;
@@ -1082,6 +1085,7 @@ main(int argc, char *argv[])
     case 'f':        /* capture filter */
     case 'g':        /* enable group read access on file(s) */
     case 'i':        /* Use interface x */
+    case LONGOPT_SET_TSTAMP_TYPE: /* Set capture timestamp type */
     case 'p':        /* Don't capture in promiscuous mode */
 #ifdef HAVE_PCAP_REMOTE
     case 'A':        /* Authentication */
@@ -1226,7 +1230,15 @@ main(int argc, char *argv[])
       break;
     case 'L':        /* Print list of link-layer types and exit */
 #ifdef HAVE_LIBPCAP
-      list_link_layer_types = TRUE;
+      caps_queries |= CAPS_QUERY_LINK_TYPES;
+#else
+      capture_option_specified = TRUE;
+      arg_error = TRUE;
+#endif
+      break;
+    case LONGOPT_LIST_TSTAMP_TYPES: /* List possible timestamp types */
+#ifdef HAVE_LIBPCAP
+      caps_queries |= CAPS_QUERY_TIMESTAMP_TYPES;
 #else
       capture_option_specified = TRUE;
       arg_error = TRUE;
@@ -1601,12 +1613,13 @@ main(int argc, char *argv[])
   }
 
 #ifdef HAVE_LIBPCAP
-  if (list_link_layer_types) {
-    /* We're supposed to list the link-layer types for an interface;
+  if (caps_queries) {
+    /* We're supposed to list the link-layer/timestamp types for an interface;
        did the user also specify a capture file to be read? */
     if (cf_name) {
       /* Yes - that's bogus. */
-      cmdarg_err("You can't specify -L and a capture file to be read.");
+      cmdarg_err("You can't specify %s and a capture file to be read.",
+                 caps_queries & CAPS_QUERY_LINK_TYPES ? "-L" : "--list-time-stamp-types");
       exit_status = INVALID_OPTION;
       goto clean_exit;
     }
@@ -2079,7 +2092,7 @@ main(int argc, char *argv[])
     }
 
     /* if requested, list the link layer types and exit */
-    if (list_link_layer_types) {
+    if (caps_queries) {
         guint i;
 
         /* Get the list of link-layer types for the capture devices. */
@@ -2087,6 +2100,7 @@ main(int argc, char *argv[])
           interface_options  interface_opts;
           if_capabilities_t *caps;
           char *auth_str = NULL;
+          int if_caps_queries = caps_queries;
 
           interface_opts = g_array_index(global_capture_opts.ifaces, interface_options, i);
 #ifdef HAVE_PCAP_REMOTE
@@ -2102,12 +2116,19 @@ main(int argc, char *argv[])
             exit_status = INVALID_CAPABILITY;
             goto clean_exit;
           }
-          if (caps->data_link_types == NULL) {
+          if ((if_caps_queries & CAPS_QUERY_LINK_TYPES) && caps->data_link_types == NULL) {
             cmdarg_err("The capture device \"%s\" has no data link types.", interface_opts.name);
             exit_status = INVALID_DATA_LINK;
             goto clean_exit;
           }
-          capture_opts_print_if_capabilities(caps, interface_opts.name, interface_opts.monitor_mode);
+          if ((if_caps_queries & CAPS_QUERY_TIMESTAMP_TYPES) && caps->timestamp_types == NULL) {
+            cmdarg_err("The capture device \"%s\" has no timestamp types.", interface_opts.name);
+            exit_status = INVALID_TIMESTAMP_TYPE;
+            goto clean_exit;
+          }
+          if (interface_opts.monitor_mode)
+                if_caps_queries |= CAPS_MONITOR_MODE;
+          capture_opts_print_if_capabilities(caps, interface_opts.name, if_caps_queries);
           free_if_capabilities(caps);
         }
         exit_status = EXIT_SUCCESS;