nmbd uses only first IP address even when more are returned by DNS

[bernd.casimir at daimlerchrysler.com]

Hi,
to get rid of the inconsistency problems between WINS and DNS we modified
the SAMBA nmbd
to use DNS as the only source to respond to WINS name queries
(WINS-to-DNS-Proxy).
To be able to respond to domain controller queries we added some lines of
code that adds
"-PDC" to the DNS query when a client requests a name with type "1B" and "
-DC" if it is type "1C".

Unfortunately nmbd uses only the first IP address of the DNS response -
even when several
domain controllers are reported by DNS.

The reason for this behaviour is the function "interpret_addr" (defined in
lib/util.c) called by asyncdns_process
and queue_dns_query (both defined in nmbd/asyncdns.c) which uses h_addr
from "gethostbyname"
and not the complete list (h_addr_list):

struct hostent {
   char    *h_name;        /* official name of host */
   char    **h_aliases;    /* alias list */
   int     h_addrtype;     /* host address type */
   int     h_length;       /* length of address */
   char    **h_addr_list;  /* list of addresses */
}
#define h_addr  h_addr_list[0]  /* for backward compatibility */


uint32 interpret_addr(const char *str)
{
        struct hostent *hp;
        uint32 res;

        if (strcmp(str,"0.0.0.0") == 0)
                return(0);
        if (strcmp(str,"255.255.255.255") == 0)
                return(0xFFFFFFFF);

  /* if it's in the form of an IP address then get the lib to interpret it
*/
        if (is_ipaddress(str)) {
                res = inet_addr(str);
        } else {
                /* otherwise assume it's a network name of some sort and
use
                        sys_gethostbyname */
                if ((hp = sys_gethostbyname(str)) == 0) {
                        DEBUG(3,("sys_gethostbyname: Unknown host.
%s\n",str));
                        return 0;
                }

                if(hp->h_addr == NULL) {
                        DEBUG(3,("sys_gethostbyname: host address is
invalid for host %s\n",str));
                        return 0;
                }
                putip((char *)&res,(char *)hp->h_addr);
        }

        if (res == (uint32)-1)
                return(0);

        return(res);
}



Do you think this can be modified in a later version of samba?

Over 30.000 productive clients are running very fine with this solution.
The only drawback is that there must be a memory leak in nmbd as the used
memory
increases from hour to hour and we have to restart nmbd every night...

PS: If you are interested in the modifications for a WINS-to-DNS-Proxy I
can post the diffs...

Thanks,
Bernd