Introduce UID_NONE value, for cache records which are not the target of a CNAME.

src/cache.c

@@ -77,17 +77,20 @@ static void cache_link(struct crec *crecp);
 static void rehash(int size);
 static void cache_hash(struct crec *crecp);
 
-static unsigned int next_uid(void)
+void next_uid(struct crec *crecp)
 {
   static unsigned int uid = 0;
 
-  uid++;
+  if (crecp->uid == UID_NONE)
+    {
+      uid++;
   
-  /* uid == 0 used to indicate CNAME to interface name. */
-  if (uid == SRC_INTERFACE)
-    uid++;
+      /* uid == 0 used to indicate CNAME to interface name. */
+      if (uid == UID_NONE)
+	uid++;
       
-  return uid;
+      crecp->uid = uid;
+    }
 }
 
 void cache_init(void)
@@ -105,7 +108,7 @@ void cache_init(void)
 	{
 	  cache_link(crecp);
 	  crecp->flags = 0;
-	  crecp->uid = next_uid();
+	  crecp->uid = UID_NONE;
 	}
     }
   
@@ -204,7 +207,7 @@ static void cache_free(struct crec *crecp)
 {
   crecp->flags &= ~F_FORWARD;
   crecp->flags &= ~F_REVERSE;
-  crecp->uid = next_uid(); /* invalidate CNAMES pointing to this. */
+  crecp->uid = UID_NONE; /* invalidate CNAMES pointing to this. */
 
   if (cache_tail)
     cache_tail->next = crecp;
@@ -787,8 +790,9 @@ static void add_hosts_cname(struct crec *target)
 	crec->ttd = a->ttl;
 	crec->name.namep = a->alias;
 	crec->addr.cname.target.cache = target;
+	next_uid(target);
 	crec->addr.cname.uid = target->uid;
-	crec->uid = next_uid();
+	crec->uid = UID_NONE;
 	cache_hash(crec);
 	add_hosts_cname(crec); /* handle chains */
       }
@@ -1071,7 +1075,7 @@ void cache_reload(void)
 	  cache->name.namep = a->alias;
 	  cache->addr.cname.target.int_name = intr;
 	  cache->addr.cname.uid = SRC_INTERFACE;
-	  cache->uid = next_uid();
+	  cache->uid = UID_NONE;
 	  cache_hash(cache);
 	  add_hosts_cname(cache); /* handle chains */
 	}
@@ -1201,8 +1205,9 @@ static void add_dhcp_cname(struct crec *target, time_t ttd)
 	      aliasc->ttd = ttd;
 	    aliasc->name.namep = a->alias;
 	    aliasc->addr.cname.target.cache = target;
+	    next_uid(target);
 	    aliasc->addr.cname.uid = target->uid;
-	    aliasc->uid = next_uid();
+	    aliasc->uid = UID_NONE;
 	    cache_hash(aliasc);
 	    add_dhcp_cname(aliasc, ttd);
 	  }
@@ -1290,7 +1295,7 @@ void cache_add_dhcp_entry(char *host_name, int prot,
 	crec->ttd = ttd;
       crec->addr.addr = *host_address;
       crec->name.namep = host_name;
-      crec->uid = next_uid();
+      crec->uid = UID_NONE;
       cache_hash(crec);
 
       add_dhcp_cname(crec, ttd);

src/dnsmasq.h

@@ -468,8 +468,12 @@ struct crec {
 #define F_SERVFAIL  (1u<<28)
 #define F_RCODE     (1u<<29)
 
+#define UID_NONE      0
 /* Values of uid in crecs with F_CONFIG bit set. */
-#define SRC_INTERFACE 0
+/* cname to uid SRC_INTERFACE are to interface names,
+   so use UID_NONE for that to eliminate clashes with
+   any other uid */
+#define SRC_INTERFACE UID_NONE
 #define SRC_CONFIG    1
 #define SRC_HOSTS     2
 #define SRC_AH        3
@@ -1117,6 +1121,7 @@ extern struct daemon {
 
 /* cache.c */
 void cache_init(void);
+void next_uid(struct crec *crecp);
 void log_query(unsigned int flags, char *name, struct all_addr *addr, char *arg); 
 char *record_source(unsigned int index);
 char *querystr(char *desc, unsigned short type);

src/rfc1035.c

@@ -788,6 +788,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 			  newc->addr.cname.uid = 1; 
 			  if (cpp)
 			    {
+			      next_uid(newc);
 			      cpp->addr.cname.target.cache = newc;
 			      cpp->addr.cname.uid = newc->uid;
 			    }
@@ -844,6 +845,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 		      newc = cache_insert(name, &addr, now, attl, flags | F_FORWARD | secflag);
 		      if (newc && cpp)
 			{
+			  next_uid(newc);
 			  cpp->addr.cname.target.cache = newc;
 			  cpp->addr.cname.uid = newc->uid;
 			}
@@ -870,6 +872,7 @@ int extract_addresses(struct dns_header *header, size_t qlen, char *name, time_t
 		  newc = cache_insert(name, NULL, now, ttl ? ttl : cttl, F_FORWARD | F_NEG | flags | (secure ? F_DNSSECOK : 0));	
 		  if (newc && cpp)
 		    {
+		      next_uid(newc);
 		      cpp->addr.cname.target.cache = newc;
 		      cpp->addr.cname.uid = newc->uid;
 		    }