[solanum.git] / ircd / dns.c

/*
 *  dns.c: An interface to the resolver module in authd
 *  (based somewhat on ircd-ratbox dns.c)
 *
 *  Copyright (C) 2005 Aaron Sethman <androsyn@ratbox.org>
 *  Copyright (C) 2005-2012 ircd-ratbox development team
 *  Copyright (C) 2016 William Pitcock <nenolod@dereferenced.org>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301
 *  USA
 */

#include <stdinc.h>
#include <ratbox_lib.h>
#include <client.h>
#include <ircd_defs.h>
#include <parse.h>
#include <dns.h>
#include <match.h>
#include <logger.h>
#include <s_conf.h>
#include <client.h>
#include <send.h>
#include <numeric.h>
#include <msg.h>

#define DNS_IDTABLE_SIZE 0x2000

#define DNS_HOST_IPV4		((char)'4')
#define DNS_HOST_IPV6		((char)'6')
#define DNS_REVERSE_IPV4	((char)'R')
#define DNS_REVERSE_IPV6	((char)'S')

static void submit_dns(uint16_t id, char type, const char *addr);

struct dnsreq
{
	DNSCB callback;
	void *data;
};

static struct dnsreq querytable[DNS_IDTABLE_SIZE];

static uint16_t
assign_dns_id(void)
{
	static uint16_t id = 1;
	int loopcnt = 0;
	while(1)
	{
		if(++loopcnt > DNS_IDTABLE_SIZE)
			return 0;
		if(id < DNS_IDTABLE_SIZE - 1 || id == 0)
			id++;
		else
			id = 1;
		if(querytable[id].callback == NULL)
			break;
	}
	return (id);
}

static void
handle_dns_failure(uint16_t xid)
{
	struct dnsreq *req;

	req = &querytable[xid];
	if(req->callback == NULL)
		return;

	req->callback("FAILED", 0, 0, req->data);
	req->callback = NULL;
	req->data = NULL;
}

void
cancel_lookup(uint16_t xid)
{
	querytable[xid].callback = NULL;
	querytable[xid].data = NULL;
}

uint16_t
lookup_hostname(const char *hostname, int aftype, DNSCB callback, void *data)
{
	struct dnsreq *req;
	int aft;
	uint16_t nid;
	check_authd();
	nid = assign_dns_id();
	if((nid = assign_dns_id()) == 0)
		return 0;

	req = &querytable[nid];

	req->callback = callback;
	req->data = data;

#ifdef RB_IPV6
	if(aftype == AF_INET6)
		aft = 6;
	else
#endif
		aft = 4;

	submit_dns(nid, aft == 4 ? DNS_HOST_IPV4 : DNS_HOST_IPV6, hostname);
	return (nid);
}

uint16_t
lookup_ip(const char *addr, int aftype, DNSCB callback, void *data)
{
	struct dnsreq *req;
	int aft;
	uint16_t nid;
	check_authd();

	if((nid = assign_dns_id()) == 0)
		return 0;
		
	req = &querytable[nid];

	req->callback = callback;
	req->data = data;

#ifdef RB_IPV6
	if(aftype == AF_INET6)
		aft = 6;
	else
#endif
		aft = 4;

	submit_dns(nid, aft == 4 ? DNS_REVERSE_IPV4 : DNS_REVERSE_IPV6, addr);
	return (nid);
}

void
dns_results_callback(const char *callid, const char *status, const char *type, const char *results)
{
	struct dnsreq *req;
	uint16_t nid;
	int st;
	int aft;
	long lnid = strtol(callid, NULL, 16);

	if(lnid > DNS_IDTABLE_SIZE || lnid == 0)
		return;
	nid = (uint16_t)lnid;
	req = &querytable[nid];
	st = *status == 'O';
	aft = *type == '6' || *type == 'S' ? 6 : 4;
	if(req->callback == NULL)
	{
		/* got cancelled..oh well */
		req->data = NULL;
		return;
	}
#ifdef RB_IPV6
	if(aft == 6)
		aft = AF_INET6;
	else
#endif
		aft = AF_INET;

	req->callback(results, st, aft, req->data);
	req->callback = NULL;
	req->data = NULL;
}

void
report_dns_servers(struct Client *source_p)
{
#if 0
	rb_dlink_node *ptr;
	RB_DLINK_FOREACH(ptr, nameservers.head)
	{
		sendto_one_numeric(source_p, RPL_STATSDEBUG, "A %s", (char *)ptr->data);
	}
#endif
}

static void
submit_dns(uint16_t nid, char type, const char *addr)
{
	if(authd_helper == NULL)
	{
		handle_dns_failure(nid);
		return;
	}
	rb_helper_write(authd_helper, "D %x %c %s", nid, type, addr);
}
Commit	Line	Data
7d2852b4 AC	1	/*
	2	* dns.c: An interface to the resolver module in authd
	3	* (based somewhat on ircd-ratbox dns.c)
	4	*
	5	* Copyright (C) 2005 Aaron Sethman <androsyn@ratbox.org>
	6	* Copyright (C) 2005-2012 ircd-ratbox development team
	7	* Copyright (C) 2016 William Pitcock <nenolod@dereferenced.org>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
	22	* USA
	23	*/
	24
	25	#include <stdinc.h>
	26	#include <ratbox_lib.h>
1d997451	27	#include <client.h>
7d2852b4 AC	28	#include <ircd_defs.h>
	29	#include <parse.h>
	30	#include <dns.h>
	31	#include <match.h>
	32	#include <logger.h>
	33	#include <s_conf.h>
	34	#include <client.h>
	35	#include <send.h>
	36	#include <numeric.h>
	37	#include <msg.h>
	38
	39	#define DNS_IDTABLE_SIZE 0x2000
	40
1bf29198 AC	41	#define DNS_HOST_IPV4 ((char)'4')
	42	#define DNS_HOST_IPV6 ((char)'6')
	43	#define DNS_REVERSE_IPV4 ((char)'R')
	44	#define DNS_REVERSE_IPV6 ((char)'S')
7d2852b4	45
1bf29198	46	static void submit_dns(uint16_t id, char type, const char *addr);
7d2852b4	47
7d2852b4 AC	48	struct dnsreq
	49	{
	50	DNSCB callback;
	51	void *data;
	52	};
	53
	54	static struct dnsreq querytable[DNS_IDTABLE_SIZE];
	55
	56	static uint16_t
	57	assign_dns_id(void)
	58	{
	59	static uint16_t id = 1;
	60	int loopcnt = 0;
	61	while(1)
	62	{
	63	if(++loopcnt > DNS_IDTABLE_SIZE)
	64	return 0;
	65	if(id < DNS_IDTABLE_SIZE - 1 \|\| id == 0)
	66	id++;
	67	else
	68	id = 1;
	69	if(querytable[id].callback == NULL)
	70	break;
	71	}
	72	return (id);
	73	}
	74
7d2852b4 AC	75	static void
	76	handle_dns_failure(uint16_t xid)
	77	{
	78	struct dnsreq *req;
	79
	80	req = &querytable[xid];
	81	if(req->callback == NULL)
	82	return;
	83
	84	req->callback("FAILED", 0, 0, req->data);
	85	req->callback = NULL;
	86	req->data = NULL;
	87	}
	88
	89	void
	90	cancel_lookup(uint16_t xid)
	91	{
	92	querytable[xid].callback = NULL;
	93	querytable[xid].data = NULL;
	94	}
	95
	96	uint16_t
	97	lookup_hostname(const char hostname, int aftype, DNSCB callback, void data)
	98	{
	99	struct dnsreq *req;
	100	int aft;
	101	uint16_t nid;
	102	check_authd();
	103	nid = assign_dns_id();
	104	if((nid = assign_dns_id()) == 0)
	105	return 0;
	106
	107	req = &querytable[nid];
	108
	109	req->callback = callback;
	110	req->data = data;
	111
	112	#ifdef RB_IPV6
	113	if(aftype == AF_INET6)
	114	aft = 6;
	115	else
	116	#endif
	117	aft = 4;
	118
1bf29198	119	submit_dns(nid, aft == 4 ? DNS_HOST_IPV4 : DNS_HOST_IPV6, hostname);
7d2852b4 AC	120	return (nid);
	121	}
	122
	123	uint16_t
	124	lookup_ip(const char addr, int aftype, DNSCB callback, void data)
	125	{
	126	struct dnsreq *req;
	127	int aft;
	128	uint16_t nid;
	129	check_authd();
	130
	131	if((nid = assign_dns_id()) == 0)
	132	return 0;
	133
	134	req = &querytable[nid];
	135
	136	req->callback = callback;
	137	req->data = data;
	138
	139	#ifdef RB_IPV6
	140	if(aftype == AF_INET6)
	141	aft = 6;
	142	else
	143	#endif
	144	aft = 4;
	145
1bf29198	146	submit_dns(nid, aft == 4 ? DNS_REVERSE_IPV4 : DNS_REVERSE_IPV6, addr);
7d2852b4 AC	147	return (nid);
	148	}
	149
fb7d74ef	150	void
1bf29198	151	dns_results_callback(const char callid, const char status, const char type, const char results)
7d2852b4 AC	152	{
	153	struct dnsreq *req;
	154	uint16_t nid;
	155	int st;
	156	int aft;
	157	long lnid = strtol(callid, NULL, 16);
	158
	159	if(lnid > DNS_IDTABLE_SIZE \|\| lnid == 0)
	160	return;
	161	nid = (uint16_t)lnid;
	162	req = &querytable[nid];
1bf29198 AC	163	st = *status == 'O';
1bf29198 AC	164	aft = type == '6' \|\| type == 'S' ? 6 : 4;
7d2852b4 AC	165	if(req->callback == NULL)
	166	{
	167	/* got cancelled..oh well */
	168	req->data = NULL;
	169	return;
	170	}
	171	#ifdef RB_IPV6
	172	if(aft == 6)
	173	aft = AF_INET6;
	174	else
	175	#endif
	176	aft = AF_INET;
	177
	178	req->callback(results, st, aft, req->data);
	179	req->callback = NULL;
	180	req->data = NULL;
	181	}
	182
7d2852b4 AC	183	void
	184	report_dns_servers(struct Client *source_p)
	185	{
	186	#if 0
	187	rb_dlink_node *ptr;
	188	RB_DLINK_FOREACH(ptr, nameservers.head)
	189	{
	190	sendto_one_numeric(source_p, RPL_STATSDEBUG, "A %s", (char *)ptr->data);
	191	}
	192	#endif
	193	}
	194
7d2852b4	195	static void
1bf29198	196	submit_dns(uint16_t nid, char type, const char *addr)
7d2852b4 AC	197	{
	198	if(authd_helper == NULL)
	199	{
	200	handle_dns_failure(nid);
	201	return;
	202	}
1bf29198	203	rb_helper_write(authd_helper, "D %x %c %s", nid, type, addr);
7d2852b4	204	}