Fix various fatal errors around --send-eth

FPEngine.cc

@@ -118,7 +118,7 @@ FPNetworkControl::~FPNetworkControl() {
 
 /* (Re)-Initialize object's state (default parameter setup and nsock
  * initialization). */
-void FPNetworkControl::init(const char *ifname) {
+void FPNetworkControl::init(const char *ifname, devtype iftype) {
 
   /* Init congestion control parameters */
   this->cc_init();
@@ -161,7 +161,7 @@ void FPNetworkControl::init(const char *ifname) {
   netutil_eth_t *ethsd = NULL;
 
   /* Obtain raw socket or check that we can obtain an eth descriptor. */
-  if (!raw_socket_or_eth(o.sendpref, ifname, &this->rawsd, &ethsd)) {
+  if (!raw_socket_or_eth(o.sendpref, ifname, iftype, &this->rawsd, &ethsd)) {
     fatal("Couldn't obtain raw socket or eth handle in %s", __func__);
   }
 
@@ -1122,7 +1122,7 @@ int FPEngine6::os_scan(std::vector<Target *> &Targets) {
 
   /* Initialize variables, timers, etc. */
   gettimeofday(&begin_time, NULL);
-  global_netctl.init(Targets[0]->deviceName());
+  global_netctl.init(Targets[0]->deviceName(), Targets[0]->ifType());
   for (size_t i = 0; i < Targets.size(); i++) {
     if (o.debugging > 3) {
       log_write(LOG_PLAIN, "[FPEngine] Allocating FPHost6 for %s %s\n",
@@ -2511,6 +2511,7 @@ int FPPacket::setEthernet(const Target *target) {
         else {
           memcpy(this->eth_hdr.srcmac, src_mac, 6);
           memcpy(this->eth_hdr.dstmac, dst_mac, 6);
+          Strncpy(this->eth_hdr.devname, devname, sizeof(this->eth_hdr.devname));
         }
       }
     }

FPEngine.h

@@ -157,7 +157,7 @@ class FPNetworkControl {
  public:
   FPNetworkControl();
   ~FPNetworkControl();
-  void init(const char *ifname);
+  void init(const char *ifname, devtype iftype);
   int register_caller(FPHost *newcaller);
   int unregister_caller(FPHost *oldcaller);
   int setup_sniffer(const char *iface, const char *bfp_filter);

idle_scan.cc

@@ -599,7 +599,7 @@ static void initialize_idleproxy(struct idle_proxy_info *proxy, char *proxyName,
 
   /* Now lets send some probes to check IP ID algorithm ... */
   /* First we need a raw socket ... */
-  if (!raw_socket_or_eth(o.sendpref, proxy->host.deviceName(),
+  if (!raw_socket_or_eth(o.sendpref, proxy->host.deviceName(), proxy->host.ifType(),
         &proxy->rawsd, &proxy->eth.ethsd)) {
     fatal("%s: Failed to open raw socket or ethernet handle", __func__);
   }

libnetutil/netutil.cc

@@ -1128,12 +1128,21 @@ int netutil_raw_socket(const char *device) {
 #endif
 }
 
-int raw_socket_or_eth(int sendpref, const char *ifname,
+int raw_socket_or_eth(int sendpref, const char *ifname, devtype iftype,
     int *rawsd, netutil_eth_t **ethsd) {
   assert(rawsd != NULL);
   *rawsd = -1;
   assert(ethsd != NULL);
   *ethsd = NULL;
+
+#ifndef WIN32
+  /* In general, on Windows we need to use Ether headers.
+   * On other platforms, avoid it. */
+  if (iftype != devt_ethernet) {
+    sendpref = PACKET_SEND_IP;
+  }
+#endif
+
   bool may_try_eth = ifname && !(sendpref & PACKET_SEND_IP_STRONG);
   bool may_try_ip = !(sendpref & PACKET_SEND_ETH_STRONG);
   bool try_eth = may_try_eth && (sendpref & PACKET_SEND_ETH);

libnetutil/netutil.h

@@ -330,7 +330,7 @@ int netutil_raw_socket(const char *device);
 #define PACKET_SEND_IP_WEAK     0x08
 #define PACKET_SEND_IP_STRONG   0x10
 #define PACKET_SEND_IP (PACKET_SEND_IP_WEAK | PACKET_SEND_IP_STRONG)
-int raw_socket_or_eth(int sendpref, const char *ifname,
+int raw_socket_or_eth(int sendpref, const char *ifname, devtype iftype,
     int *rawsd, netutil_eth_t **ethsd);
 
 /* Takes a protocol number like IPPROTO_TCP, IPPROTO_UDP, or

osscan2.cc

@@ -1176,8 +1176,10 @@ struct eth_nfo *HostOsScanStats::fill_eth_nfo(struct eth_nfo *eth, netutil_eth_t
   if (ethsd == NULL)
     return NULL;
 
+  if (netutil_eth_datalink(ethsd) == DLT_EN10MB) {
     memcpy(eth->srcmac, target->SrcMACAddress(), sizeof(eth->srcmac));
-  memcpy(eth->dstmac, target->NextHopMACAddress(), sizeof(eth->srcmac));
+    memcpy(eth->dstmac, target->NextHopMACAddress(), sizeof(eth->dstmac));
+  }
   eth->ethsd = ethsd;
   eth->devname[0] = '\0';
 
@@ -1335,8 +1337,9 @@ HostOsScan::HostOsScan(Target *t) {
   pd = NULL;
   rawsd = -1;
   ethsd = NULL;
+  int sendpref = o.sendpref;
 
-  if (!raw_socket_or_eth(o.sendpref, t->deviceName(), &rawsd, &ethsd)) {
+  if (!raw_socket_or_eth(sendpref, t->deviceName(), t->ifType(), &rawsd, &ethsd)) {
     fatal("%s: Failed to open raw socket or ethernet device", __func__);
   }
   if (rawsd >= 0)

scan_engine.cc

@@ -956,14 +956,8 @@ void UltraScanInfo::Init(std::vector<Target *> &Targets, const struct scan_lists
       assert(!(sendpref & PACKET_SEND_IP_STRONG));
       sendpref = PACKET_SEND_ETH;
     }
-#ifndef WIN32
-    /* Windows does loopback via Npcap (eth),
-     * but we want to avoid that for everyone else. */
-    if (Targets[0]->ifType() == devt_loopback) {
-      sendpref = PACKET_SEND_IP;
-    }
-#endif
-    if (!raw_socket_or_eth(sendpref, Targets[0]->deviceName(), &rawsd, &ethsd)) {
+    if (!raw_socket_or_eth(sendpref, Targets[0]->deviceName(), Targets[0]->ifType(),
+          &rawsd, &ethsd)) {
       fatal("Couldn't open a raw socket or eth handle.");
     }
     /* Raw scan types also need to know the source IP. */

traceroute.cc

@@ -837,7 +837,8 @@ TracerouteState::TracerouteState(std::vector<Target *> &targets) {
 
   assert(targets.size() > 0);
 
-  if (!raw_socket_or_eth(o.sendpref, targets[0]->deviceName(), &rawsd, &ethsd)) {
+  if (!raw_socket_or_eth(o.sendpref, targets[0]->deviceName(), targets[0]->ifType(),
+        &rawsd, &ethsd)) {
     fatal("traceroute: socket troubles");
   }