solanum-vs-hackint-and-char.../authd/dns.c
Elizabeth Myers 6445c1cf0b rehash: don't restart authd for DNS reloads
This could lead to pretty nasty things, like losing DNS (and in the
future, ident) queries. That's a Bad Thing™.
2016-03-09 03:46:04 -06:00

183 lines
4.2 KiB
C

/* authd/dns.h - header for authd DNS functions
* Copyright (c) 2016 William Pitcock <nenolod@dereferenced.org>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice is present in all copies.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "authd.h"
#include "dns.h"
#include "res.h"
static void
submit_dns_answer(void *userdata, struct DNSReply *reply)
{
struct dns_request *req = userdata;
char response[64] = "*";
char status = 'E';
if (reply == NULL)
{
rb_helper_write(authd_helper, "E %s E %c *", req->reqid, req->type);
goto cleanup;
}
switch (req->type)
{
case '4':
if (GET_SS_FAMILY(&reply->addr) == AF_INET)
{
status = 'O';
rb_inet_ntop_sock((struct sockaddr *) &reply->addr, response, sizeof(response));
}
break;
#ifdef RB_IPV6
case '6':
if (GET_SS_FAMILY(&reply->addr) == AF_INET6)
{
char tmpres[63];
rb_inet_ntop_sock((struct sockaddr *) &reply->addr, tmpres, sizeof(tmpres));
if (*tmpres == ':')
{
rb_strlcpy(response, "0", sizeof(response));
rb_strlcat(response, tmpres, sizeof(response));
}
else
rb_strlcpy(response, tmpres, sizeof(response));
status = 'O';
}
break;
#endif
case 'R':
{
struct sockaddr_in *ip, *ip_fwd;
ip = (struct sockaddr_in *) &req->addr;
ip_fwd = (struct sockaddr_in *) &reply->addr;
if(ip->sin_addr.s_addr == ip_fwd->sin_addr.s_addr && strlen(reply->h_name) < 63)
{
rb_strlcpy(response, reply->h_name, sizeof(response));
status = 'O';
}
}
break;
#ifdef RB_IPV6
case 'S':
{
struct sockaddr_in6 *ip, *ip_fwd;
ip = (struct sockaddr_in6 *) &req->addr;
ip_fwd = (struct sockaddr_in6 *) &reply->addr;
if(memcmp(&ip->sin6_addr, &ip_fwd->sin6_addr, sizeof(struct in6_addr)) == 0 && strlen(reply->h_name) < 63)
{
rb_strlcpy(response, reply->h_name, sizeof(response));
status = 'O';
}
}
break;
#endif
default:
exit(7);
}
rb_helper_write(authd_helper, "E %s %c %c %s", req->reqid, status, req->type, response);
cleanup:
rb_free(req);
}
void
resolve_dns(int parc, char *parv[])
{
struct dns_request *req;
char *requestid = parv[1];
char *qtype = parv[2];
char *rec = parv[3];
int type;
req = rb_malloc(sizeof(*req));
rb_strlcpy(req->reqid, requestid, sizeof(req->reqid));
req->type = *qtype;
switch (req->type)
{
case '4':
type = T_A;
break;
case '6':
type = T_AAAA;
break;
case 'R':
case 'S':
if(!rb_inet_pton_sock(rec, (struct sockaddr *) &req->addr))
exit(6);
type = T_PTR;
break;
}
req->query.ptr = req;
req->query.callback = submit_dns_answer;
if (type != T_PTR)
gethost_byname_type(rec, &req->query, type);
else
gethost_byaddr(&req->addr, &req->query);
}
void
enumerate_nameservers(const char *rid, const char letter)
{
char buf[40 * IRCD_MAXNS]; /* Plenty */
char *c = buf;
int i;
if (!irc_nscount)
{
/* Shouldn't happen */
rb_helper_write(authd_helper, "X %s %c NONAMESERVERS", rid, letter);
return;
}
for(i = 0; i < irc_nscount; i++)
{
char addr[40];
int ret;
rb_inet_ntop_sock((struct sockaddr *)&irc_nsaddr_list[i], addr, sizeof(addr));
if (!addr[0])
{
/* Shouldn't happen */
rb_helper_write(authd_helper, "X %s %c INVALIDNAMESERVER", rid, letter);
return;
}
ret = snprintf(c, 40, "%s ", addr);
c += (size_t)ret;
}
*(--c) = '\0';
rb_helper_write(authd_helper, "Y %s %c %s", rid, letter, buf);
}
void
reload_nameservers(const char letter)
{
/* Not a whole lot to it */
restart_resolver();
}