Fetch an indication of whether the interface supports capturing in

monitor mode at the same time that we fetch its list of link-layer
types.  Support fetching that list in monitor mode, as the list may be
different in regular and monitor mode.  If the interface supports
monitor mode, when printing the list of link-layer types, indicate
whether they're fetched in monitor mode or not, as tcpdump 4.1.x does.

svn path=/trunk/; revision=32789

1 files changed, 57 insertions, 13 deletions

diff --git a/capture_ifinfo.c b/capture_ifinfo.c
index 53e024749f..e9fc5347a0 100644
--- a/capture_ifinfo.c
+++ b/capture_ifinfo.c
@@ -155,21 +155,23 @@ capture_interface_list(int *err, char **err_str)
 
 /* XXX - We parse simple text output to get our interface list.  Should
  * we use "real" data serialization instead, e.g. via XML? */
-GList *
-capture_pcap_linktype_list(const gchar *ifname, char **err_str)
+if_capabilities_t *
+capture_get_if_capabilities(const gchar *ifname, gboolean monitor_mode,
+                            char **err_str)
 {
-    GList     *linktype_list = NULL;
-    int        err, i;
-    gchar     *msg;
-    gchar    **raw_list, **lt_parts;
-    data_link_info_t *data_link_info;
+    if_capabilities_t *caps;
+    GList              *linktype_list = NULL;
+    int                 err, i;
+    gchar              *msg;
+    gchar             **raw_list, **lt_parts;
+    data_link_info_t   *data_link_info;
 
-    g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Linktype List ...");
+    g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Interface Capabilities ...");
 
     /* Try to get our interface list */
-    err = sync_linktype_list_open(ifname, &msg);
+    err = sync_if_capabilities_open(ifname, monitor_mode, &msg);
     if (err != 0) {
-        g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Linktype List failed!");
+        g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Interface Capabilities failed!");
         if (err_str) {
             *err_str = msg;
         } else {
@@ -186,7 +188,45 @@ capture_pcap_linktype_list(const gchar *ifname, char **err_str)
 #endif
     g_free(msg);
 
-    for (i = 0; raw_list[i] != NULL; i++) {
+    /*
+     * First line is 0 if monitor mode isn't supported, 1 if it is.
+     */
+    if (raw_list[0] == NULL || *raw_list[0] == '\0') {
+        g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Interface Capabilities returned no information!");
+        if (err_str) {
+            *err_str = g_strdup("Dumpcap returned no interface capability information");
+        }
+        return NULL;
+    }
+
+    /*
+     * Allocate the interface capabilities structure.
+     */
+    caps = g_malloc(sizeof *caps);
+    switch (*raw_list[0]) {
+
+    case '0':
+        caps->can_set_rfmon = FALSE;
+        break;
+
+    case '1':
+        caps->can_set_rfmon = TRUE;
+        break;
+
+    default:
+        g_log(LOG_DOMAIN_CAPTURE, G_LOG_LEVEL_MESSAGE, "Capture Interface Capabilities returned bad information!");
+        if (err_str) {
+            *err_str = g_strdup_printf("Dumpcap returned \"%s\" for monitor-mode capability",
+                                       raw_list[0]);
+        }
+        g_free(caps);
+        return NULL;
+    }
+
+    /*
+     * The rest are link-layer types.
+     */
+    for (i = 1; raw_list[i] != NULL; i++) {
         /* ...and what if the interface name has a tab in it, Mr. Clever Programmer? */
         lt_parts = g_strsplit(raw_list[i], "\t", 3);
         if (lt_parts[0] == NULL || lt_parts[1] == NULL || lt_parts[2] == NULL) {
@@ -208,10 +248,14 @@ capture_pcap_linktype_list(const gchar *ifname, char **err_str)
 
     /* Check to see if we built a list */
     if (linktype_list == NULL) {
+        /* No. */
         if (err_str)
-            *err_str = NULL;
+            *err_str = g_strdup("Dumpcap returned no link-layer types");
+        g_free(caps);
+        return NULL;
     }
-    return linktype_list;
+    caps->data_link_types = linktype_list;
+    return caps;
 }
 
 #endif /* HAVE_LIBPCAP */