solanum-vs-hackint-and-char.../modules/m_sasl.c

366 lines
11 KiB
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)
{
if (!strcmp(parv[1], "*"))
{
sendto_one(source_p, form_str(ERR_SASLABORTED), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
source_p->localClient->sasl_out = 0;
return;
}
sendto_one(saslserv_p, ":%s ENCAP %s SASL %s %s H %s %s %c",
me.id, saslserv_p->servptr->name, source_p->id, saslserv_p->id,
source_p->host, source_p->sockhost,
IsSSL(source_p) ? 'S' : 'P');
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
{
if (!strcmp(parv[1], "*"))
{
sendto_one(source_p, form_str(ERR_SASLABORTED), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
sendto_one(agent_p, ":%s ENCAP %s SASL %s %s D A", me.id, agent_p->servptr->name, source_p->id, agent_p->id);
source_p->localClient->sasl_out = 0;
return;
}
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);
}