[solanum.git] / modules / m_sasl.c

/* modules/m_sasl.c
 *   Copyright (C) 2006 Michael Tharp <gxti@partiallystapled.com>
 *   Copyright (C) 2006 charybdis development team
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * 1.Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * 2.Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * 3.The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * 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 "stdinc.h"

#include "client.h"
#include "hash.h"
#include "send.h"
#include "msg.h"
#include "modules.h"
#include "numeric.h"
#include "reject.h"
#include "s_serv.h"
#include "s_stats.h"
#include "string.h"
#include "s_newconf.h"
#include "s_conf.h"

static const char sasl_desc[] = "Provides SASL authentication support";

static void m_authenticate(struct MsgBuf *, struct Client *, struct Client *, int, const char **);
static void me_sasl(struct MsgBuf *, struct Client *, struct Client *, int, const char **);
static void me_mechlist(struct MsgBuf *, struct Client *, struct Client *, int, const char **);

static void abort_sasl(struct Client *);
static void abort_sasl_exit(hook_data_client_exit *);

static void advertise_sasl(struct Client *);
static void advertise_sasl_exit(hook_data_client_exit *);

static unsigned int CLICAP_SASL = 0;
static char mechlist_buf[BUFSIZE];

struct Message authenticate_msgtab = {
	"AUTHENTICATE", 0, 0, 0, 0,
	{{m_authenticate, 2}, {m_authenticate, 2}, mg_ignore, mg_ignore, mg_ignore, {m_authenticate, 2}}
};
struct Message sasl_msgtab = {
	"SASL", 0, 0, 0, 0,
	{mg_ignore, mg_ignore, mg_ignore, mg_ignore, {me_sasl, 5}, mg_ignore}
};
struct Message mechlist_msgtab = {
	"MECHLIST", 0, 0, 0, 0,
	{mg_ignore, mg_ignore, mg_ignore, mg_ignore, {me_mechlist, 2}, mg_ignore}
};

mapi_clist_av1 sasl_clist[] = {
	&authenticate_msgtab, &sasl_msgtab, &mechlist_msgtab, NULL
};
mapi_hfn_list_av1 sasl_hfnlist[] = {
	{ "new_local_user",	(hookfn) abort_sasl },
	{ "client_exit",	(hookfn) abort_sasl_exit },
	{ "new_remote_user",	(hookfn) advertise_sasl },
	{ "client_exit",	(hookfn) advertise_sasl_exit },
	{ NULL, NULL }
};

static bool
sasl_visible(struct Client *client_p)
{
	struct Client *agent_p = NULL;

	if (ConfigFileEntry.sasl_service)
		agent_p = find_named_client(ConfigFileEntry.sasl_service);

	return agent_p != NULL && IsService(agent_p);
}

static const char *
sasl_data(struct Client *client_p)
{
	return *mechlist_buf != 0 ? mechlist_buf : NULL;
}

static struct ClientCapability capdata_sasl = {
	.visible = sasl_visible,
	.data = sasl_data,
	.flags = CLICAP_FLAGS_STICKY,
};

static int
_modinit(void)
{
	memset(mechlist_buf, 0, sizeof mechlist_buf);
	CLICAP_SASL = capability_put(cli_capindex, "sasl", &capdata_sasl);
	return 0;
}

static void
_moddeinit(void)
{
	capability_orphan(cli_capindex, "sasl");
}

DECLARE_MODULE_AV2(sasl, _modinit, _moddeinit, sasl_clist, NULL, sasl_hfnlist, NULL, NULL, sasl_desc);

static void
m_authenticate(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p,
	int parc, const char *parv[])
{
	struct Client *agent_p = NULL;
	struct Client *saslserv_p = NULL;

	/* They really should use CAP for their own sake. */
	if(!IsCapable(source_p, CLICAP_SASL))
		return;

	if(source_p->localClient->sasl_next_retry > rb_current_time())
	{
		sendto_one(source_p, form_str(RPL_LOAD2HI), me.name, EmptyString(source_p->name) ? "*" : source_p->name, msgbuf_p->cmd);
		return;
	}

	if(strlen(client_p->id) == 3)
	{
		exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
		return;
	}

	if (*parv[1] == ':' || strchr(parv[1], ' '))
	{
		exit_client(client_p, client_p, client_p, "Malformed AUTHENTICATE");
		return;
	}

	saslserv_p = find_named_client(ConfigFileEntry.sasl_service);
	if(saslserv_p == NULL || !IsService(saslserv_p))
	{
		sendto_one(source_p, form_str(ERR_SASLABORTED), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
		return;
	}

	if(source_p->localClient->sasl_complete)
	{
		*source_p->localClient->sasl_agent = '\0';
		source_p->localClient->sasl_complete = 0;
	}

	if(strlen(parv[1]) > 400)
	{
		sendto_one(source_p, form_str(ERR_SASLTOOLONG), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
		return;
	}

	if(!*source_p->id)
	{
		/* Allocate a UID. */
		rb_strlcpy(source_p->id, generate_uid(), sizeof(source_p->id));
		add_to_id_hash(source_p->id, source_p);
	}

	if(*source_p->localClient->sasl_agent)
		agent_p = find_id(source_p->localClient->sasl_agent);

	if(agent_p == NULL)
	{
		sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s H %s %s",
					me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
					source_p->host, source_p->sockhost);

		if (source_p->certfp != NULL)
			sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s S %s %s",
						me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
						parv[1], source_p->certfp);
		else
			sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s S %s",
						me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
						parv[1]);

		rb_strlcpy(source_p->localClient->sasl_agent, saslserv_p->id, IDLEN);
	}
	else
		sendto_one(agent_p, ":%s ENCAP %s SASL %s %s C %s",
				me.id, agent_p->servptr->name, source_p->id, agent_p->id,
				parv[1]);
	source_p->localClient->sasl_out++;
}

static void
me_sasl(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p,
	int parc, const char *parv[])
{
	struct Client *target_p, *agent_p;

	/* Let propagate if not addressed to us, or if broadcast.
	 * Only SASL agents can answer global requests.
	 */
	if(strncmp(parv[2], me.id, 3))
		return;

	if((target_p = find_id(parv[2])) == NULL)
		return;

	if((agent_p = find_id(parv[1])) == NULL)
		return;

	if(source_p != agent_p->servptr) /* WTF?! */
		return;

	/* We only accept messages from SASL agents; these must have umode +S
	 * (so the server must be listed in a service{} block).
	 */
	if(!IsService(agent_p))
		return;

	/* Reject if someone has already answered. */
	if(*target_p->localClient->sasl_agent && strncmp(parv[1], target_p->localClient->sasl_agent, IDLEN))
		return;
	else if(!*target_p->localClient->sasl_agent)
		rb_strlcpy(target_p->localClient->sasl_agent, parv[1], IDLEN);

	if(*parv[3] == 'C')
	{
		sendto_one(target_p, "AUTHENTICATE %s", parv[4]);
		target_p->localClient->sasl_messages++;
	}
	else if(*parv[3] == 'D')
	{
		if(*parv[4] == 'F')
		{
			sendto_one(target_p, form_str(ERR_SASLFAIL), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
			/* Failures with zero messages are just "unknown mechanism" errors; don't count those. */
			if(target_p->localClient->sasl_messages > 0)
			{
				if(*target_p->name)
				{
					/* Allow 2 tries before rate-limiting as some clients try EXTERNAL
					 * then PLAIN right after it if the auth failed, causing the client to be
					 * rate-limited immediately and not being able to login with SASL.
					 */
					if (target_p->localClient->sasl_failures++ > 0)
						target_p->localClient->sasl_next_retry = rb_current_time() + (1 << MIN(target_p->localClient->sasl_failures + 1, 8));
				}
				else if(throttle_add((struct sockaddr*)&target_p->localClient->ip))
				{
					exit_client(target_p, target_p, &me, "Too many failed authentication attempts");
					return;
				}
			}
		}
		else if(*parv[4] == 'S')
		{
			sendto_one(target_p, form_str(RPL_SASLSUCCESS), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
			target_p->localClient->sasl_failures = 0;
			target_p->localClient->sasl_complete = 1;
			ServerStats.is_ssuc++;
		}
		*target_p->localClient->sasl_agent = '\0'; /* Blank the stored agent so someone else can answer */
		target_p->localClient->sasl_messages = 0;
	}
	else if(*parv[3] == 'M')
		sendto_one(target_p, form_str(RPL_SASLMECHS), me.name, EmptyString(target_p->name) ? "*" : target_p->name, parv[4]);
}

static void
me_mechlist(struct MsgBuf *msgbuf_p, struct Client *client_p, struct Client *source_p,
	    int parc, const char *parv[])
{
	rb_strlcpy(mechlist_buf, parv[1], sizeof mechlist_buf);
}

/* If the client never finished authenticating but is
 * registering anyway, abort the exchange.
 */
static void
abort_sasl(struct Client *data)
{
	if(data->localClient->sasl_out == 0 || data->localClient->sasl_complete)
		return;

	data->localClient->sasl_out = data->localClient->sasl_complete = 0;
	ServerStats.is_sbad++;

	if(!IsClosing(data))
		sendto_one(data, form_str(ERR_SASLABORTED), me.name, EmptyString(data->name) ? "*" : data->name);

	if(*data->localClient->sasl_agent)
	{
		struct Client *agent_p = find_id(data->localClient->sasl_agent);
		if(agent_p)
		{
			sendto_one(agent_p, ":%s ENCAP %s SASL %s %s D A", me.id, agent_p->servptr->name,
					data->id, agent_p->id);
			return;
		}
	}

	sendto_server(NULL, NULL, CAP_TS6|CAP_ENCAP, NOCAPS, ":%s ENCAP * SASL %s * D A", me.id,
			data->id);
}

static void
abort_sasl_exit(hook_data_client_exit *data)
{
	if (data->target->localClient)
		abort_sasl(data->target);
}

static void
advertise_sasl(struct Client *client_p)
{
	if (!ConfigFileEntry.sasl_service)
		return;

	if (irccmp(client_p->name, ConfigFileEntry.sasl_service))
		return;

	sendto_local_clients_with_capability(CLICAP_CAP_NOTIFY, ":%s CAP * NEW :sasl", me.name);
}

static void
advertise_sasl_exit(hook_data_client_exit *data)
{
	if (!ConfigFileEntry.sasl_service)
		return;

	if (irccmp(data->target->name, ConfigFileEntry.sasl_service))
		return;

	sendto_local_clients_with_capability(CLICAP_CAP_NOTIFY, ":%s CAP * DEL :sasl", me.name);
}
Commit	Line	Data
212380e3 AC	1	/* modules/m_sasl.c
212380e3 AC	2	* Copyright (C) 2006 Michael Tharp <gxti@partiallystapled.com>
f62f94b0	3	* Copyright (C) 2006 charybdis development team
212380e3 AC	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions are
	7	* met:
	8	*
	9	* 1.Redistributions of source code must retain the above copyright notice,
	10	* this list of conditions and the following disclaimer.
	11	* 2.Redistributions in binary form must reproduce the above copyright
	12	* notice, this list of conditions and the following disclaimer in the
	13	* documentation and/or other materials provided with the distribution.
	14	* 3.The name of the author may not be used to endorse or promote products
	15	* derived from this software without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	19	* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	20	* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
	21	* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
	22	* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	23	* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	25	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
	26	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	27	* POSSIBILITY OF SUCH DAMAGE.
212380e3 AC	28	*/
	29
	30	#include "stdinc.h"
	31
	32	#include "client.h"
	33	#include "hash.h"
	34	#include "send.h"
	35	#include "msg.h"
	36	#include "modules.h"
	37	#include "numeric.h"
37289346	38	#include "reject.h"
212380e3 AC	39	#include "s_serv.h"
	40	#include "s_stats.h"
	41	#include "string.h"
7d33cce8 MT	42	#include "s_newconf.h"
7d33cce8 MT	43	#include "s_conf.h"
212380e3	44
eeabf33a EM	45	static const char sasl_desc[] = "Provides SASL authentication support";
eeabf33a EM	46
3c7d6fcc EM	47	static void m_authenticate(struct MsgBuf , struct Client , struct Client , int, const char *);
	48	static void me_sasl(struct MsgBuf , struct Client , struct Client , int, const char *);
	49	static void me_mechlist(struct MsgBuf , struct Client , struct Client , int, const char *);
212380e3 AC	50
	51	static void abort_sasl(struct Client *);
	52	static void abort_sasl_exit(hook_data_client_exit *);
	53
12565204 AC	54	static void advertise_sasl(struct Client *);
	55	static void advertise_sasl_exit(hook_data_client_exit *);
	56
da3e5fcb AC	57	static unsigned int CLICAP_SASL = 0;
da3e5fcb AC	58	static char mechlist_buf[BUFSIZE];
193d4db3	59
212380e3	60	struct Message authenticate_msgtab = {
7baa37a9	61	"AUTHENTICATE", 0, 0, 0, 0,
ef3ab8e3	62	{{m_authenticate, 2}, {m_authenticate, 2}, mg_ignore, mg_ignore, mg_ignore, {m_authenticate, 2}}
212380e3 AC	63	};
212380e3 AC	64	struct Message sasl_msgtab = {
7baa37a9	65	"SASL", 0, 0, 0, 0,
212380e3 AC	66	{mg_ignore, mg_ignore, mg_ignore, mg_ignore, {me_sasl, 5}, mg_ignore}
212380e3 AC	67	};
da3e5fcb AC	68	struct Message mechlist_msgtab = {
	69	"MECHLIST", 0, 0, 0, 0,
	70	{mg_ignore, mg_ignore, mg_ignore, mg_ignore, {me_mechlist, 2}, mg_ignore}
	71	};
212380e3	72
55abcbb2	73	mapi_clist_av1 sasl_clist[] = {
da3e5fcb	74	&authenticate_msgtab, &sasl_msgtab, &mechlist_msgtab, NULL
212380e3 AC	75	};
	76	mapi_hfn_list_av1 sasl_hfnlist[] = {
	77	{ "new_local_user", (hookfn) abort_sasl },
	78	{ "client_exit", (hookfn) abort_sasl_exit },
12565204 AC	79	{ "new_remote_user", (hookfn) advertise_sasl },
12565204 AC	80	{ "client_exit", (hookfn) advertise_sasl_exit },
212380e3 AC	81	{ NULL, NULL }
	82	};
	83
3c7d6fcc	84	static bool
38ffccf8	85	sasl_visible(struct Client *client_p)
193d4db3 AC	86	{
	87	struct Client *agent_p = NULL;
	88
	89	if (ConfigFileEntry.sasl_service)
	90	agent_p = find_named_client(ConfigFileEntry.sasl_service);
	91
	92	return agent_p != NULL && IsService(agent_p);
	93	}
	94
da3e5fcb	95	static const char *
38ffccf8	96	sasl_data(struct Client *client_p)
da3e5fcb AC	97	{
	98	return *mechlist_buf != 0 ? mechlist_buf : NULL;
	99	}
	100
193d4db3 AC	101	static struct ClientCapability capdata_sasl = {
193d4db3 AC	102	.visible = sasl_visible,
da3e5fcb	103	.data = sasl_data,
193d4db3 AC	104	.flags = CLICAP_FLAGS_STICKY,
	105	};
	106
	107	static int
	108	_modinit(void)
	109	{
da3e5fcb	110	memset(mechlist_buf, 0, sizeof mechlist_buf);
193d4db3 AC	111	CLICAP_SASL = capability_put(cli_capindex, "sasl", &capdata_sasl);
	112	return 0;
	113	}
	114
	115	static void
	116	_moddeinit(void)
	117	{
	118	capability_orphan(cli_capindex, "sasl");
	119	}
	120
3abc337f	121	DECLARE_MODULE_AV2(sasl, _modinit, _moddeinit, sasl_clist, NULL, sasl_hfnlist, NULL, NULL, sasl_desc);
212380e3	122
3c7d6fcc	123	static void
428ca87b	124	m_authenticate(struct MsgBuf msgbuf_p, struct Client client_p, struct Client *source_p,
212380e3 AC	125	int parc, const char *parv[])
	126	{
	127	struct Client *agent_p = NULL;
7d33cce8	128	struct Client *saslserv_p = NULL;
212380e3 AC	129
	130	/* They really should use CAP for their own sake. */
	131	if(!IsCapable(source_p, CLICAP_SASL))
3c7d6fcc	132	return;
212380e3	133
9d07a42d MM	134	if(source_p->localClient->sasl_next_retry > rb_current_time())
	135	{
	136	sendto_one(source_p, form_str(RPL_LOAD2HI), me.name, EmptyString(source_p->name) ? "*" : source_p->name, msgbuf_p->cmd);
	137	return;
	138	}
	139
	140	if(strlen(client_p->id) == 3)
1b19fe8b JT	141	{
1b19fe8b JT	142	exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
3c7d6fcc	143	return;
1b19fe8b JT	144	}
1b19fe8b JT	145
ac88154f AJ	146	if (*parv[1] == ':' \|\| strchr(parv[1], ' '))
	147	{
	148	exit_client(client_p, client_p, client_p, "Malformed AUTHENTICATE");
	149	return;
	150	}
	151
7d33cce8	152	saslserv_p = find_named_client(ConfigFileEntry.sasl_service);
9d07a42d	153	if(saslserv_p == NULL \|\| !IsService(saslserv_p))
7d33cce8 MT	154	{
7d33cce8 MT	155	sendto_one(source_p, form_str(ERR_SASLABORTED), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
3c7d6fcc	156	return;
7d33cce8 MT	157	}
7d33cce8 MT	158
c6bc97fd	159	if(source_p->localClient->sasl_complete)
212380e3	160	{
51535fcb	161	*source_p->localClient->sasl_agent = '\0';
c6bc97fd	162	source_p->localClient->sasl_complete = 0;
212380e3 AC	163	}
	164
	165	if(strlen(parv[1]) > 400)
	166	{
	167	sendto_one(source_p, form_str(ERR_SASLTOOLONG), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
3c7d6fcc	168	return;
212380e3 AC	169	}
	170
	171	if(!*source_p->id)
	172	{
	173	/* Allocate a UID. */
4d5a902f	174	rb_strlcpy(source_p->id, generate_uid(), sizeof(source_p->id));
212380e3 AC	175	add_to_id_hash(source_p->id, source_p);
	176	}
	177
c6bc97fd AC	178	if(*source_p->localClient->sasl_agent)
c6bc97fd AC	179	agent_p = find_id(source_p->localClient->sasl_agent);
212380e3 AC	180
212380e3 AC	181	if(agent_p == NULL)
572488e0	182	{
1cae2411 MM	183	sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s H %s %s",
	184	me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
	185	source_p->host, source_p->sockhost);
a3fa9d81	186
802710b5	187	if (source_p->certfp != NULL)
6fb9f214 MM	188	sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s S %s %s",
	189	me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
	190	parv[1], source_p->certfp);
572488e0	191	else
6fb9f214 MM	192	sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s S %s",
	193	me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
	194	parv[1]);
7d33cce8	195
c6bc97fd	196	rb_strlcpy(source_p->localClient->sasl_agent, saslserv_p->id, IDLEN);
572488e0	197	}
212380e3	198	else
6fb9f214 MM	199	sendto_one(agent_p, ":%s ENCAP %s SASL %s %s C %s",
6fb9f214 MM	200	me.id, agent_p->servptr->name, source_p->id, agent_p->id,
7d33cce8	201	parv[1]);
c6bc97fd	202	source_p->localClient->sasl_out++;
212380e3 AC	203	}
212380e3 AC	204
3c7d6fcc	205	static void
428ca87b	206	me_sasl(struct MsgBuf msgbuf_p, struct Client client_p, struct Client *source_p,
212380e3 AC	207	int parc, const char *parv[])
	208	{
	209	struct Client target_p, agent_p;
	210
	211	/* Let propagate if not addressed to us, or if broadcast.
	212	* Only SASL agents can answer global requests.
	213	*/
	214	if(strncmp(parv[2], me.id, 3))
3c7d6fcc	215	return;
212380e3 AC	216
212380e3 AC	217	if((target_p = find_id(parv[2])) == NULL)
3c7d6fcc	218	return;
212380e3	219
212380e3	220	if((agent_p = find_id(parv[1])) == NULL)
3c7d6fcc	221	return;
212380e3 AC	222
212380e3 AC	223	if(source_p != agent_p->servptr) /* WTF?! */
3c7d6fcc	224	return;
212380e3 AC	225
	226	/* We only accept messages from SASL agents; these must have umode +S
	227	* (so the server must be listed in a service{} block).
	228	*/
	229	if(!IsService(agent_p))
3c7d6fcc	230	return;
212380e3 AC	231
212380e3 AC	232	/* Reject if someone has already answered. */
c6bc97fd	233	if(*target_p->localClient->sasl_agent && strncmp(parv[1], target_p->localClient->sasl_agent, IDLEN))
3c7d6fcc	234	return;
c6bc97fd AC	235	else if(!*target_p->localClient->sasl_agent)
c6bc97fd AC	236	rb_strlcpy(target_p->localClient->sasl_agent, parv[1], IDLEN);
212380e3	237
f62f94b0	238	if(*parv[3] == 'C')
37289346	239	{
212380e3	240	sendto_one(target_p, "AUTHENTICATE %s", parv[4]);
37289346 MM	241	target_p->localClient->sasl_messages++;
37289346 MM	242	}
212380e3 AC	243	else if(*parv[3] == 'D')
212380e3 AC	244	{
834579ce MM	245	if(*parv[4] == 'F')
834579ce MM	246	{
212380e3	247	sendto_one(target_p, form_str(ERR_SASLFAIL), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
9d07a42d	248	/* Failures with zero messages are just "unknown mechanism" errors; don't count those. */
834579ce	249	if(target_p->localClient->sasl_messages > 0)
37289346	250	{
9d07a42d MM	251	if(*target_p->name)
9d07a42d MM	252	{
46ef49c3 X	253	/* Allow 2 tries before rate-limiting as some clients try EXTERNAL
	254	* then PLAIN right after it if the auth failed, causing the client to be
	255	* rate-limited immediately and not being able to login with SASL.
	256	*/
	257	if (target_p->localClient->sasl_failures++ > 0)
23f5c317	258	target_p->localClient->sasl_next_retry = rb_current_time() + (1 << MIN(target_p->localClient->sasl_failures + 1, 8));
9d07a42d MM	259	}
9d07a42d MM	260	else if(throttle_add((struct sockaddr*)&target_p->localClient->ip))
37289346 MM	261	{
	262	exit_client(target_p, target_p, &me, "Too many failed authentication attempts");
	263	return;
	264	}
	265	}
	266	}
834579ce MM	267	else if(*parv[4] == 'S')
834579ce MM	268	{
212380e3	269	sendto_one(target_p, form_str(RPL_SASLSUCCESS), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
9d07a42d	270	target_p->localClient->sasl_failures = 0;
c6bc97fd	271	target_p->localClient->sasl_complete = 1;
47adde3d	272	ServerStats.is_ssuc++;
212380e3	273	}
c6bc97fd	274	target_p->localClient->sasl_agent = '\0'; / Blank the stored agent so someone else can answer */
37289346	275	target_p->localClient->sasl_messages = 0;
212380e3	276	}
dbd8ca2b MM	277	else if(*parv[3] == 'M')
dbd8ca2b MM	278	sendto_one(target_p, form_str(RPL_SASLMECHS), me.name, EmptyString(target_p->name) ? "*" : target_p->name, parv[4]);
212380e3 AC	279	}
212380e3 AC	280
3c7d6fcc	281	static void
da3e5fcb AC	282	me_mechlist(struct MsgBuf msgbuf_p, struct Client client_p, struct Client *source_p,
	283	int parc, const char *parv[])
	284	{
	285	rb_strlcpy(mechlist_buf, parv[1], sizeof mechlist_buf);
da3e5fcb AC	286	}
da3e5fcb AC	287
212380e3 AC	288	/* If the client never finished authenticating but is
	289	* registering anyway, abort the exchange.
	290	*/
	291	static void
	292	abort_sasl(struct Client *data)
	293	{
c6bc97fd	294	if(data->localClient->sasl_out == 0 \|\| data->localClient->sasl_complete)
212380e3 AC	295	return;
212380e3 AC	296
c6bc97fd	297	data->localClient->sasl_out = data->localClient->sasl_complete = 0;
47adde3d	298	ServerStats.is_sbad++;
212380e3 AC	299
	300	if(!IsClosing(data))
	301	sendto_one(data, form_str(ERR_SASLABORTED), me.name, EmptyString(data->name) ? "*" : data->name);
	302
c6bc97fd	303	if(*data->localClient->sasl_agent)
212380e3	304	{
c6bc97fd	305	struct Client *agent_p = find_id(data->localClient->sasl_agent);
212380e3 AC	306	if(agent_p)
	307	{
	308	sendto_one(agent_p, ":%s ENCAP %s SASL %s %s D A", me.id, agent_p->servptr->name,
	309	data->id, agent_p->id);
	310	return;
	311	}
	312	}
	313
	314	sendto_server(NULL, NULL, CAP_TS6\|CAP_ENCAP, NOCAPS, ":%s ENCAP * SASL %s * D A", me.id,
	315	data->id);
	316	}
	317
	318	static void
	319	abort_sasl_exit(hook_data_client_exit *data)
	320	{
c23902ae AC	321	if (data->target->localClient)
c23902ae AC	322	abort_sasl(data->target);
212380e3 AC	323	}
212380e3 AC	324
12565204 AC	325	static void
	326	advertise_sasl(struct Client *client_p)
	327	{
	328	if (!ConfigFileEntry.sasl_service)
	329	return;
	330
	331	if (irccmp(client_p->name, ConfigFileEntry.sasl_service))
	332	return;
	333
	334	sendto_local_clients_with_capability(CLICAP_CAP_NOTIFY, ":%s CAP * NEW :sasl", me.name);
	335	}
	336
	337	static void
	338	advertise_sasl_exit(hook_data_client_exit *data)
	339	{
	340	if (!ConfigFileEntry.sasl_service)
	341	return;
	342
	343	if (irccmp(data->target->name, ConfigFileEntry.sasl_service))
	344	return;
	345
	346	sendto_local_clients_with_capability(CLICAP_CAP_NOTIFY, ":%s CAP * DEL :sasl", me.name);
	347	}