From a quick look at the hostap driver, it appears that newer versions

support the Radiotap header.

diff --git a/pcap-linux.c b/pcap-linux.c
index 1a238891f4fe4ab3c01db9083fc86b9b17104211..051741e7b7c69cd93224a4dc97e43b9017396e02 100644 (file)
--- a/pcap-linux.c
+++ b/pcap-linux.c
@@ -2796,8 +2796,10 @@ enter_rfmon_mode_wext(pcap_t *handle, int sock_fd, const char *device)
                         * Hostap driver, use this one.
                         * Set monitor mode first.
                         * You can set it to 0 to get DLT_IEEE80211,
-                        * 1 to get DLT_PRISM, or 2 to get
-                        * DLT_IEEE80211_RADIO_AVS.
+                        * 1 to get DLT_PRISM, 2 to get
+                        * DLT_IEEE80211_RADIO_AVS, and, with more
+                        * recent versions of the driver, 3 to get
+                        * DLT_IEEE80211_RADIO.
                         */
                        if ((priv[i].set_args & IW_PRIV_TYPE_MASK) != IW_PRIV_TYPE_INT)
                                break;
@@ -3060,8 +3062,19 @@ enter_rfmon_mode_wext(pcap_t *handle, int sock_fd, const char *device)
 
        case MONITOR_HOSTAP:
                /*
-                * Select the AVS header if we can, otherwise
-                * select the Prism header.
+                * Try to select the radiotap header.
+                */
+               memset(&ireq, 0, sizeof ireq);
+               strncpy(ireq.ifr_ifrn.ifrn_name, device,
+                   sizeof ireq.ifr_ifrn.ifrn_name);
+               ireq.ifr_ifrn.ifrn_name[sizeof ireq.ifr_ifrn.ifrn_name - 1] = 0;
+               args[0] = 3;    /* request radiotap header */
+               memcpy(ireq.u.name, args, sizeof (int));
+               if (ioctl(sock_fd, cmd, &ireq) != -1)
+                       break;  /* success */
+
+               /*
+                * That failed.  Try to select the AVS header.
                 */
                memset(&ireq, 0, sizeof ireq);
                strncpy(ireq.ifr_ifrn.ifrn_name, device,
@@ -3069,18 +3082,19 @@ enter_rfmon_mode_wext(pcap_t *handle, int sock_fd, const char *device)
                ireq.ifr_ifrn.ifrn_name[sizeof ireq.ifr_ifrn.ifrn_name - 1] = 0;
                args[0] = 2;    /* request AVS header */
                memcpy(ireq.u.name, args, sizeof (int));
-               if (ioctl(sock_fd, cmd, &ireq) == -1) {
-                       /*
-                        * Failure - try the Prism header.
-                        */
-                       memset(&ireq, 0, sizeof ireq);
-                       strncpy(ireq.ifr_ifrn.ifrn_name, device,
-                           sizeof ireq.ifr_ifrn.ifrn_name);
-                       ireq.ifr_ifrn.ifrn_name[sizeof ireq.ifr_ifrn.ifrn_name - 1] = 0;
-                       args[0] = 1;    /* request Prism header */
-                       memcpy(ireq.u.name, args, sizeof (int));
-                       ioctl(sock_fd, cmd, &ireq);
-               }
+               if (ioctl(sock_fd, cmd, &ireq) != -1)
+                       break;  /* success */
+
+               /*
+                * That failed.  Try to select the Prism header.
+                */
+               memset(&ireq, 0, sizeof ireq);
+               strncpy(ireq.ifr_ifrn.ifrn_name, device,
+                   sizeof ireq.ifr_ifrn.ifrn_name);
+               ireq.ifr_ifrn.ifrn_name[sizeof ireq.ifr_ifrn.ifrn_name - 1] = 0;
+               args[0] = 1;    /* request Prism header */
+               memcpy(ireq.u.name, args, sizeof (int));
+               ioctl(sock_fd, cmd, &ireq);
                break;
 
        case MONITOR_PRISM: