First attempt to do IPv6 on the resolver

SRC/plugins/dns/dns.c

@@ -1,11 +1,12 @@
 /*
- * DNS plugin. 
- * $Id$
+ * DNS plugin. $Id$
  */
 
 #define IN_PLUGIN
 #include "../../echoping.h"
-
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
 #include <netinet/in.h>
 #include <arpa/nameser.h>
 #include <resolv.h>
@@ -36,8 +37,7 @@ nsError (error, domain)
 	int             error;
 	char           *domain;
 {
-  switch (error)
-    {
+	switch (error) {
 	case HOST_NOT_FOUND:
 		err_ret("Unknown domain: %s\n", domain);
 		return -1;
@@ -56,8 +56,7 @@ nsError (error, domain)
 void
 dns_usage(const char *msg)
 {
-  if (msg)
-    {
+	if (msg) {
 		fprintf(stderr, "Error: %s\n", msg);
 	}
 	poptPrintUsage(dns_poptcon, stderr, 0);
@@ -87,10 +86,8 @@ init (const int argc, const char **argv)
 	};
 	dns_poptcon = poptGetContext(NULL, argc,
 				     argv, options, POPT_CONTEXT_KEEP_FIRST);
-  while ((value = poptGetNextOpt (dns_poptcon)) > 0)
-    {
-      if (value < -1)
-	{
+	while ((value = poptGetNextOpt(dns_poptcon)) > 0) {
+		if (value < -1) {
 			sprintf(msg, "%s: %s",
 			 poptBadOption(dns_poptcon, POPT_BADOPTION_NOALIAS),
 				poptStrerror(value));
@@ -103,10 +100,12 @@ init (const int argc, const char **argv)
 		dns_usage("Mandatory request missing");
 	if ((type_name == NULL) || !strcmp(type_name, ""))
 		type = T_A;
-  else
-    {
+	else {
 		upper_type_name = to_upper(type_name);
-      /* TODO: a better algorithm. Use dns_rdatatype_fromtext in BIND ? */
+		/*
+		 * TODO: a better algorithm. Use dns_rdatatype_fromtext in
+		 * BIND ?
+		 */
 		if (!strcmp(upper_type_name, "A"))
 			type = T_A;
 		else if (!strcmp(upper_type_name, "AAAA"))
@@ -136,22 +135,39 @@ start (struct addrinfo *res)
 {
 	struct sockaddr name_server_sockaddr;
 	struct sockaddr_in name_server_sockaddr_in;
+	struct sockaddr_in6 name_server_sockaddr_in6;
 	name_server = *res;
 	name_server_sockaddr = *name_server.ai_addr;
+	if (name_server_sockaddr.sa_family == AF_INET) {
 		/* Converts a generic sockaddr to an IPv4 sockaddr_in */
 		(void)memcpy((void *)&name_server_sockaddr_in, &name_server_sockaddr,
 			     sizeof(struct sockaddr));
+	} else if (name_server_sockaddr.sa_family == AF_INET6) {
+#ifdef HAVE_RES_EXT
+		/* Converts a generic sockaddr to an IPv6 sockaddr_in6 */
+		(void)memcpy((void *)&name_server_sockaddr_in6, &name_server_sockaddr,
+			     sizeof(struct sockaddr));
+#else
+		err_quit("IPv6 name servers not supported on this platform, may be you should use the -4 option");
+#endif
+	} else {
+		err_quit("Unknown family for address of the server");
+	}
 	if (res_init() < 0)
 		err_sys("res_init");
-  _res.nsaddr_list[0] = name_server_sockaddr_in;	/* TODO: and IPv6? We now if we have _res_ext (xBSD) so we should use HAVE_RES_EXT here */
+	if (name_server_sockaddr.sa_family == AF_INET) {
+		_res.nsaddr_list[0] = name_server_sockaddr_in;
+	} else if (name_server_sockaddr.sa_family == AF_INET6) {
+#ifdef HAVE_RES_EXT
+		(void)memcpy(_res_ext.nsaddr_list, &name_server_sockaddr_in6, sizeof(struct sockaddr_in6));
+#endif
+	}
 	_res.nscount = 1;
 	_res.options &= ~(RES_DNSRCH | RES_DEFNAMES | RES_NOALIASES);
-  if (use_tcp)
-    {
+	if (use_tcp) {
 		_res.options |= RES_USEVC;
 	}
-  if (no_recurse)
-    {
+	if (no_recurse) {
 		_res.options &= ~RES_RECURSE;
 	}
 }
@@ -159,25 +175,27 @@ start (struct addrinfo *res)
 int
 execute()
 {
-  union
-  {
+	union {
 		HEADER          hdr;	/* defined in resolv.h */
 		u_char          buf[PACKETSZ];	/* defined in arpa/nameser.h */
 	}               response;	/* response buffers */
 	int             response_length;	/* buffer length */
-  if ((response_length = res_query (request,	/* the domain we care about   */
+	if ((response_length = res_query(request,	/* the domain we care
+							 * about   */
 					 C_IN,	/* Internet class records     */
 					 type, (u_char *) & response,	/* response buffer */
 					 sizeof(response)))	/* buffer size    */
-      < 0)
-    {				/*If negative    */
+	    <0) {		/* If negative    */
 		nsError(h_errno, request);	/* report the error           */
 		if (h_errno == TRY_AGAIN)
 			return -1;	/* More luck next time? */
 		else
 			return -2;	/* Give in */
 	}
-  /* TODO: better analysis of the replies. For instance, replies can be in the authority section (delegation info) */
+	/*
+	 * TODO: better analysis of the replies. For instance, replies can be
+	 * in the authority section (delegation info)
+	 */
 	return 0;
 }