Files
heimdal/lib/krb5/send_to_kdc.c
Johan Danielsson 18797d20ba Check for NULL return from gethostent.
git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@2362 ec53bebd-3082-4978-b11e-865c3cabbd6b
1997-07-16 03:45:23 +00:00

108 lines
2.3 KiB
C

#include "krb5_locl.h"
RCSID("$Id$");
static int
send_and_recv (int fd,
struct sockaddr_in *addr,
const krb5_data *send,
krb5_data *recv)
{
struct fd_set fdset;
struct timeval timeout;
int ret;
int nbytes;
if (sendto (fd, send->data, send->length, 0,
(struct sockaddr *)addr, sizeof(*addr)) < 0)
return -1;
FD_ZERO(&fdset);
FD_SET(fd, &fdset);
timeout.tv_sec = 3;
timeout.tv_usec = 0;
ret = select (fd + 1, &fdset, NULL, NULL, &timeout);
if (ret <= 0)
return -1;
else {
int len;
if (ioctl (fd, FIONREAD, &nbytes) < 0)
return -1;
recv->data = malloc (nbytes);
ret = recvfrom (fd, recv->data, nbytes, 0, NULL, &len);
if (ret < 0) {
free (recv->data);
return -1;
}
recv->data = realloc (recv->data, ret);
recv->length = ret;
return 0;
}
}
krb5_error_code
krb5_sendto_kdc (krb5_context context,
const krb5_data *send,
const krb5_realm *realm,
krb5_data *receive)
{
krb5_error_code err;
char **hostlist, **hp, *p;
struct hostent *hostent;
int fd;
int port;
int i;
port = krb5_getportbyname ("kerberos", "udp", htons(88));
fd = socket (AF_INET, SOCK_DGRAM, 0);
if (fd < 0) {
krb5_free_krbhst (context, hostlist);
return errno;
}
err = krb5_get_krbhst (context, realm, &hostlist);
if (err) {
close (fd);
return err;
}
for (i = 0; i < 3; ++i)
for (hp = hostlist; (p = *hp); ++hp) {
char *addr;
char *colon;
colon = strchr (p, ':');
if (colon)
*colon = '\0';
hostent = gethostbyname (p);
if(hostent == NULL)
continue;
if (colon)
*colon++ = ':';
while ((addr = *hostent->h_addr_list++)) {
struct sockaddr_in a;
memset (&a, 0, sizeof(a));
a.sin_family = AF_INET;
if (colon) {
int tmp;
sscanf (colon, "%d", &tmp);
a.sin_port = htons(tmp);
} else
a.sin_port = port;
a.sin_addr = *((struct in_addr *)addr);
if (send_and_recv (fd, &a, send, receive) == 0) {
close (fd);
krb5_free_krbhst (context, hostlist);
return 0;
}
}
}
close (fd);
krb5_free_krbhst (context, hostlist);
return KRB5_KDC_UNREACH;
}