[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit

Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/app/dnsmasq/dnsmasq-2.86/src/arp.c b/ap/app/dnsmasq/dnsmasq-2.86/src/arp.c
new file mode 100755
index 0000000..1e4aad2
--- /dev/null
+++ b/ap/app/dnsmasq/dnsmasq-2.86/src/arp.c
@@ -0,0 +1,232 @@
+/* dnsmasq is Copyright (c) 2000-2021 Simon Kelley
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; version 2 dated June, 1991, or
+   (at your option) version 3 dated 29 June, 2007.
+ 
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+     
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "dnsmasq.h"
+
+/* Time between forced re-loads from kernel. */
+#define INTERVAL 90
+
+#define ARP_MARK  0
+#define ARP_FOUND 1  /* Confirmed */
+#define ARP_NEW   2  /* Newly created */
+#define ARP_EMPTY 3  /* No MAC addr */
+
+struct arp_record {
+  unsigned short hwlen, status;
+  int family;
+  unsigned char hwaddr[DHCP_CHADDR_MAX]; 
+  union all_addr addr;
+  struct arp_record *next;
+};
+
+static struct arp_record *arps = NULL, *old = NULL, *freelist = NULL;
+static time_t last = 0;
+
+static int filter_mac(int family, char *addrp, char *mac, size_t maclen, void *parmv)
+{
+  struct arp_record *arp;
+
+  (void)parmv;
+
+  if (maclen > DHCP_CHADDR_MAX)
+    return 1;
+
+  /* Look for existing entry */
+  for (arp = arps; arp; arp = arp->next)
+    {
+      if (family != arp->family || arp->status == ARP_NEW)
+	continue;
+      
+      if (family == AF_INET)
+	{
+	  if (arp->addr.addr4.s_addr != ((struct in_addr *)addrp)->s_addr)
+	    continue;
+	}
+      else
+	{
+	  if (!IN6_ARE_ADDR_EQUAL(&arp->addr.addr6, (struct in6_addr *)addrp))
+	    continue;
+	}
+
+      if (arp->status == ARP_EMPTY)
+	{
+	  /* existing address, was negative. */
+	  arp->status = ARP_NEW;
+	  arp->hwlen = maclen;
+	  memcpy(arp->hwaddr, mac, maclen);
+	}
+      else if (arp->hwlen == maclen && memcmp(arp->hwaddr, mac, maclen) == 0)
+	/* Existing entry matches - confirm. */
+	arp->status = ARP_FOUND;
+      else
+	continue;
+      
+      break;
+    }
+
+  if (!arp)
+    {
+      /* New entry */
+      if (freelist)
+	{
+	  arp = freelist;
+	  freelist = freelist->next;
+	}
+      else if (!(arp = whine_malloc(sizeof(struct arp_record))))
+	return 1;
+      
+      arp->next = arps;
+      arps = arp;
+      arp->status = ARP_NEW;
+      arp->hwlen = maclen;
+      arp->family = family;
+      memcpy(arp->hwaddr, mac, maclen);
+      if (family == AF_INET)
+	arp->addr.addr4.s_addr = ((struct in_addr *)addrp)->s_addr;
+      else
+	memcpy(&arp->addr.addr6, addrp, IN6ADDRSZ);
+    }
+  
+  return 1;
+}
+
+/* If in lazy mode, we cache absence of ARP entries. */
+int find_mac(union mysockaddr *addr, unsigned char *mac, int lazy, time_t now)
+{
+  struct arp_record *arp, *tmp, **up;
+  int updated = 0;
+
+ again:
+  
+  /* If the database is less then INTERVAL old, look in there */
+  if (difftime(now, last) < INTERVAL)
+    {
+      /* addr == NULL -> just make cache up-to-date */
+      if (!addr)
+	return 0;
+
+      for (arp = arps; arp; arp = arp->next)
+	{
+	  if (addr->sa.sa_family != arp->family)
+	    continue;
+	    
+	  if (arp->family == AF_INET &&
+	      arp->addr.addr4.s_addr != addr->in.sin_addr.s_addr)
+	    continue;
+	    
+	  if (arp->family == AF_INET6 && 
+	      !IN6_ARE_ADDR_EQUAL(&arp->addr.addr6, &addr->in6.sin6_addr))
+	    continue;
+	  
+	  /* Only accept positive entries unless in lazy mode. */
+	  if (arp->status != ARP_EMPTY || lazy || updated)
+	    {
+	      if (mac && arp->hwlen != 0)
+		memcpy(mac, arp->hwaddr, arp->hwlen);
+	      return arp->hwlen;
+	    }
+	}
+    }
+
+  /* Not found, try the kernel */
+  if (!updated)
+     {
+       updated = 1;
+       last = now;
+
+       /* Mark all non-negative entries */
+       for (arp = arps; arp; arp = arp->next)
+	 if (arp->status != ARP_EMPTY)
+	   arp->status = ARP_MARK;
+       
+       iface_enumerate(AF_UNSPEC, NULL, filter_mac);
+       
+       /* Remove all unconfirmed entries to old list. */
+       for (arp = arps, up = &arps; arp; arp = tmp)
+	 {
+	   tmp = arp->next;
+	   
+	   if (arp->status == ARP_MARK)
+	     {
+	       *up = arp->next;
+	       arp->next = old;
+	       old = arp;
+	     }
+	   else
+	     up = &arp->next;
+	 }
+
+       goto again;
+     }
+
+  /* record failure, so we don't consult the kernel each time
+     we're asked for this address */
+  if (freelist)
+    {
+      arp = freelist;
+      freelist = freelist->next;
+    }
+  else
+    arp = whine_malloc(sizeof(struct arp_record));
+  
+  if (arp)
+    {      
+      arp->next = arps;
+      arps = arp;
+      arp->status = ARP_EMPTY;
+      arp->family = addr->sa.sa_family;
+      arp->hwlen = 0;
+
+      if (addr->sa.sa_family == AF_INET)
+	arp->addr.addr4.s_addr = addr->in.sin_addr.s_addr;
+      else
+	memcpy(&arp->addr.addr6, &addr->in6.sin6_addr, IN6ADDRSZ);
+    }
+	  
+   return 0;
+}
+
+int do_arp_script_run(void)
+{
+  struct arp_record *arp;
+  
+  /* Notify any which went, then move to free list */
+  if (old)
+    {
+#ifdef HAVE_SCRIPT
+      if (option_bool(OPT_SCRIPT_ARP))
+	queue_arp(ACTION_ARP_DEL, old->hwaddr, old->hwlen, old->family, &old->addr);
+#endif
+      arp = old;
+      old = arp->next;
+      arp->next = freelist;
+      freelist = arp;
+      return 1;
+    }
+
+  for (arp = arps; arp; arp = arp->next)
+    if (arp->status == ARP_NEW)
+      {
+#ifdef HAVE_SCRIPT
+	if (option_bool(OPT_SCRIPT_ARP))
+	  queue_arp(ACTION_ARP, arp->hwaddr, arp->hwlen, arp->family, &arp->addr);
+#endif
+	arp->status = ARP_FOUND;
+	return 1;
+      }
+
+  return 0;
+}