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#if 0
#include "resolv.h"
#include "string.h"
#include <gpxe/dns.h>
#include "nic.h"
#include "nmb.h"
/*
* Convert a standard NUL-terminated string to an NBNS query name.
*
* Returns a pointer to the character following the constructed NBNS
* query name.
*
*/
static inline char * nbns_make_name ( char *dest, const char *name ) {
char nb_name[16];
char c;
int i;
uint16_t *d;
*(dest++) = 32; /* Length is always 32 */
/* Name encoding is as follows: pad the name with spaces to
* length 15, and add a NUL. Take this 16-byte string, split
* it into nibbles and add 0x41 to each nibble to form a byte
* of the resulting name string.
*/
memset ( nb_name, ' ', 15 );
nb_name[15] = '\0';
memcpy ( nb_name, name, strlen ( name ) ); /* Do not copy NUL */
d = ( uint16_t * ) dest;
for ( i = 0 ; i < 16 ; i++ ) {
c = nb_name[i];
*( d++ ) = htons ( ( ( c | ( c << 4 ) ) & 0x0f0f ) + 0x4141 );
}
dest = ( char * ) d;
*(dest++) = 0; /* Terminating 0-length name component */
return dest;
}
/*
* Resolve a name using NMB
*
*/
static int nmb_resolv ( struct in_addr *addr, const char *name ) {
struct dns_query query;
struct dns_query_info *query_info;
struct dns_header *reply;
struct dns_rr_info *rr_info;
struct dns_rr_info_nb *rr_info_nb;
struct sockaddr_in nameserver;
DBG ( "NMB resolving %s\n", name );
/* Set up the query data */
nameserver.sin_addr.s_addr = INADDR_BROADCAST;
nameserver.sin_port = NBNS_UDP_PORT;
memset ( &query, 0, sizeof ( query ) );
query.dns.id = htons ( 1 );
query.dns.flags = htons ( DNS_FLAG_QUERY | DNS_FLAG_OPCODE_QUERY |
DNS_FLAG_RD | DNS_FLAG_BROADCAST );
query.dns.qdcount = htons ( 1 );
query_info = ( void * ) nbns_make_name ( query.payload, name );
query_info->qtype = htons ( DNS_TYPE_NB );
query_info->qclass = htons ( DNS_CLASS_IN );
/* Issue query, wait for reply */
reply = dns_query ( &query,
( ( ( char * ) query_info )
+ sizeof ( *query_info )
- ( ( char * ) &query ) ),
&nameserver );
if ( ! reply ) {
DBG ( "NMB got no response via %@ (port %d)\n",
nameserver.sin_addr.s_addr,
nameserver.sin_port );
return 0;
}
/* Search through response for useful answers. */
rr_info = dns_find_rr ( &query, reply );
if ( ! rr_info ) {
DBG ( "NMB got invalid response\n" );
return 0;
}
/* Check type of response */
if ( ntohs ( rr_info->type ) != DNS_TYPE_NB ) {
DBG ( "NMB got answer type %hx (wanted %hx)\n",
ntohs ( rr_info->type ), DNS_TYPE_NB );
return 0;
}
/* Read response */
rr_info_nb = ( struct dns_rr_info_nb * ) rr_info;
*addr = rr_info_nb->nb_address;
DBG ( "NMB found address %@\n", addr->s_addr );
return 1;
}
struct resolver nmb_resolver __resolver = {
.name = "NMB",
.resolv = nmb_resolv,
};
#endif
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