Merge pull request #866 from pi-hole/tweak/debugging_show_IPv6_namese…

…rvers

Show also IPv6 nameservers in DEBUG_RESOLVER

src/resolve.c

@@ -71,10 +71,37 @@ static bool valid_hostname(char* name, const char* clientip)
 static void print_used_resolvers(const char *message)
 {
  logg("%s", message);
- for(unsigned int i = 0u; i < MAXNS; i++)
- logg(" %u: %s:%d", i,
- inet_ntoa(_res.nsaddr_list[i].sin_addr),
- ntohs(_res.nsaddr_list[i].sin_port));
+ for(unsigned int i = 0u; i < 2*MAXNS; i++)
+ {
+ int family;
+ in_port_t port;
+ void *addr = NULL;
+ if(i < MAXNS)
+ {
+ // IPv4 name servers
+ addr = &_res.nsaddr_list[i].sin_addr;
+ port = ntohs(_res.nsaddr_list[i].sin_port);
+ family = AF_INET;
+ }
+ else
+ {
+ // Extension name servers (typically IPv6)
+
+ // Some of the entries may not be configured
+ if(_res._u._ext.nsaddrs[i - MAXNS] == NULL)
+ continue;
+ addr = &_res._u._ext.nsaddrs[i - MAXNS]->sin6_addr;
+ port = ntohs(_res._u._ext.nsaddrs[i - MAXNS]->sin6_port);
+ family = _res._u._ext.nsaddrs[i - MAXNS]->sin6_family;
+ }
+
+ // Convert nameserver information to human-readable form
+ char nsname[INET6_ADDRSTRLEN];
+ inet_ntop(family, addr, nsname, INET6_ADDRSTRLEN);
+
+ logg(" %u: %s:%d (IPv%i)", i, nsname, port,
+ family == AF_INET ? 4 : 6);
+ }
 }
 
 static char *resolveHostname(const char *addr)