Added bpf filter option to kismet_cap_linux_wifi

capture_framework.c

@@ -727,6 +727,7 @@ int cf_handler_parse_opts(kis_capture_handler_t *caph, int argc, char *argv[]) {
         { "fixed-gps", required_argument, 0, 8},
         { "gps-name", required_argument, 0, 9},
         { "host", required_argument, 0, 10},
+        { "bpf", required_argument, 0, 11},
         { "help", no_argument, 0, 'h'},
         { 0, 0, 0, 0 }
     };
@@ -786,6 +787,8 @@ int cf_handler_parse_opts(kis_capture_handler_t *caph, int argc, char *argv[]) {
             caph->remote_host = strdup(parse_hname);
             caph->remote_port = parse_port;
             caph->reverse_server = 1;
+        } else if (r == 11) {
+          caph->bpf = strdup(optarg);
         }
     }
 
@@ -866,7 +869,8 @@ void cf_print_help(kis_capture_handler_t *caph, const char *argv0) {
                 " --gps-name [name]           Set an alternate GPS name for this source\n"
                 " --daemonize                 Background the capture tool and enter daemon\n"
                 "                             mode.\n"
-                " --list                      List supported devices detected\n",
+                " --list                      List supported devices detected\n"
+               " --bpf [filter]              Berkeley Packet Filter\n",
                 argv0, argv0);
     }
 

capture_framework.h

@@ -346,6 +346,9 @@ struct kis_capture_handler {
 
     /* Fixed GPS name */
     char *gps_name;
+
+    /* bpf filter */
+    char *bpf;
 };
 
 

capture_linux_wifi/capture_linux_wifi.c

@@ -2427,6 +2427,20 @@ int open_callback(kis_capture_handler_t *caph, uint32_t seqno, char *definition,
 
             free(filter_targets);
         }
+    } else if ((caph->bpf != NULL && caph->bpf[0] != '\0')) {
+       if (pcap_compile(local_wifi->pd, &bpf, caph->bpf, 0, 0) < 0) {
+            snprintf(errstr, STATUS_MAX, "%s unable to compile bpf filter "
+                        ": %s",
+                        local_wifi->name, pcap_geterr(local_wifi->pd));
+                        cf_send_message(caph, errstr, MSGFLAG_INFO);
+        } else {
+            if (pcap_setfilter(local_wifi->pd, &bpf) < 0) {
+                   snprintf(errstr, STATUS_MAX, "%s unable to assign bpf filter "
+                        ": %s",
+                        local_wifi->name, pcap_geterr(local_wifi->pd));
+                        cf_send_message(caph, errstr, MSGFLAG_INFO);
+            }
+        }
     }
 
     local_wifi->datalink_type = pcap_datalink(local_wifi->pd);