Add --synth-domain

src/domain.c

@@ -0,0 +1,200 @@
+/* dnsmasq is Copyright (c) 2000-2013 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"
+
+
+static struct cond_domain *search_domain(struct in_addr addr, struct cond_domain *c);
+#ifdef HAVE_IPV6
+static struct cond_domain *search_domain6(struct in6_addr *addr, struct cond_domain *c);
+#endif
+
+
+int is_name_synthetic(int flags, char *name, struct all_addr *addr)
+{
+  char *p;
+  struct cond_domain *c = NULL;
+  int prot = AF_INET;
+
+#ifdef HAVE_IPV6
+  if (flags & F_IPV6)
+    prot = AF_INET6;
+#endif
+
+  /* NB, must not alter name if we return zero */
+  for (p = name; *p; p++)
+    {
+      char c = *p;
+      
+      if ((c >='0' && c <= '9') || c == '-')
+	continue;
+      
+#ifdef HAVE_IPV6
+      if (prot == AF_INET6 && ((c >='A' && c <= 'F') || (c >='a' && c <= 'f'))) 
+	continue;
+#endif
+      
+      break;
+    }
+  
+  if (*p != '.')
+    return 0;
+  
+  *p = 0;	
+
+  for (p = name; *p; p++)
+    if (*p == '-')
+      {
+	if (prot == AF_INET)
+	  *p = '.';
+#ifdef HAVE_IPV6
+	else
+	  *p = ':';
+#endif
+      }
+ 
+  if (inet_pton(prot, name, addr))
+    for (c = daemon->synth_domains; c; c = c->next)
+      if (hostname_isequal(c->domain, p+1))
+	{
+	  if (prot == AF_INET)
+	    {
+	      if (!c->is6 &&
+		  ntohl(addr->addr.addr4.s_addr) >= ntohl(c->start.s_addr) &&
+		  ntohl(addr->addr.addr4.s_addr) <= ntohl(c->end.s_addr))
+		break;
+	    }
+#ifdef HAVE_IPV6
+	  else
+	    {
+	      u64 addrpart = addr6part(&addr->addr.addr6);
+	      
+	      if (c->is6 &&
+		  is_same_net6(&addr->addr.addr6, &c->start6, 64) &&
+		  addrpart >= addr6part(&c->start6) &&
+		  addrpart <= addr6part(&c->end6))
+		break;
+	    }
+#endif
+	}
+  
+  /* restore name */
+  for (p = name; *p; p++)
+    if (*p == '.' || *p == ':')
+      *p = '-';
+  
+  *p = '.';
+  
+  return (c != NULL);
+  
+}
+
+
+int is_rev_synth(int flag, struct all_addr *addr, char *name)
+{
+   struct cond_domain *c;
+
+   if (flag & F_IPV4 && (c = search_domain(addr->addr.addr4, daemon->synth_domains))) 
+     {
+       char *p;
+       
+       inet_ntop(AF_INET, &addr->addr.addr4, name, ADDRSTRLEN);
+       for (p = name; *p; p++)
+	 if (*p == '.')
+	   *p = '-';
+
+       strncat(name, ".", MAXDNAME);
+       strncat(name, c->domain, MAXDNAME);
+
+       return 1;
+     }
+
+#ifdef HAVE_IPV6
+   if (flag & F_IPV6 && (c = search_domain6(&addr->addr.addr6, daemon->synth_domains))) 
+     {
+       char *p;
+       
+       inet_ntop(AF_INET6, &addr->addr.addr6, name, ADDRSTRLEN);
+
+       /* IPv6 presentation address can start with ":", but valid domain names
+	  cannot start with "-" so prepend a zero in that case. */
+       if (*name == ':')
+	 {
+	   *name = '0';
+	   inet_ntop(AF_INET6, &addr->addr.addr6, name+1, ADDRSTRLEN);
+	 }
+
+       for (p = name; *p; p++)
+	 if (*p == ':')
+	   *p = '-';
+
+       strncat(name, ".", MAXDNAME);
+       strncat(name, c->domain, MAXDNAME);
+       
+       return 1;
+     }
+#endif
+   
+   return 0;
+}
+
+
+static struct cond_domain *search_domain(struct in_addr addr, struct cond_domain *c)
+{
+  for (; c; c = c->next)
+    if (!c->is6 &&
+	ntohl(addr.s_addr) >= ntohl(c->start.s_addr) &&
+        ntohl(addr.s_addr) <= ntohl(c->end.s_addr))
+      return c;
+
+  return NULL;
+}
+
+char *get_domain(struct in_addr addr)
+{
+  struct cond_domain *c;
+
+  if ((c = search_domain(addr, daemon->cond_domain)))
+    return c->domain;
+
+  return daemon->domain_suffix;
+} 
+
+#ifdef HAVE_IPV6
+static struct cond_domain *search_domain6(struct in6_addr *addr, struct cond_domain *c)
+{
+  u64 addrpart = addr6part(addr);
+  
+  for (; c; c = c->next)
+    if (c->is6 &&
+	is_same_net6(addr, &c->start6, 64) &&
+	addrpart >= addr6part(&c->start6) &&
+        addrpart <= addr6part(&c->end6))
+      return c;
+  
+  return NULL;
+}
+
+char *get_domain6(struct in6_addr *addr)
+{
+  struct cond_domain *c;
+
+  if ((c = search_domain6(addr, daemon->cond_domain)))
+    return c->domain;
+
+  return daemon->domain_suffix;
+} 
+#endif