elemental-ircd/src/listener.c

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/*
* ircd-ratbox: A slightly useful ircd.
* listener.c: Listens on a port.
*
* Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
* Copyright (C) 1996-2002 Hybrid Development Team
* Copyright (C) 2002-2005 ircd-ratbox development team
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
2007-05-14 22:21:16 +00:00
* $Id: listener.c 3446 2007-05-14 22:21:16Z jilles $
*/
#include "stdinc.h"
#include "setup.h"
#include "listener.h"
#include "client.h"
#include "irc_string.h"
#include "sprintf_irc.h"
#include "ircd.h"
#include "ircd_defs.h"
#include "numeric.h"
#include "commio.h"
#include "s_conf.h"
#include "s_newconf.h"
#include "s_stats.h"
#include "send.h"
#include "memory.h"
#include "s_auth.h"
#include "reject.h"
#ifndef INADDR_NONE
#define INADDR_NONE ((unsigned int) 0xffffffff)
#endif
#if defined(NO_IN6ADDR_ANY) && defined(IPV6)
static const struct in6_addr in6addr_any =
{ { { 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0 } } };
#endif
static PF accept_connection;
static listener_t *ListenerPollList = NULL;
static listener_t *
make_listener(struct irc_sockaddr_storage *addr)
{
listener_t *listener = (listener_t *) MyMalloc(sizeof(listener_t));
s_assert(0 != listener);
listener->name = me.name;
listener->fd = -1;
memcpy(&listener->addr, addr, sizeof(struct irc_sockaddr_storage));
listener->next = NULL;
return listener;
}
void
free_listener(listener_t *listener)
{
s_assert(NULL != listener);
if(listener == NULL)
return;
/*
* remove from listener list
*/
if(listener == ListenerPollList)
ListenerPollList = listener->next;
else
{
listener_t *prev = ListenerPollList;
for (; prev; prev = prev->next)
{
if(listener == prev->next)
{
prev->next = listener->next;
break;
}
}
}
/* free */
MyFree(listener);
}
#define PORTNAMELEN 6 /* ":31337" */
/*
* get_listener_name - return displayable listener name and port
* returns "host.foo.org:6667" for a given listener
*/
const char *
get_listener_name(const listener_t *listener)
{
static char buf[HOSTLEN + HOSTLEN + PORTNAMELEN + 4];
int port = 0;
s_assert(NULL != listener);
if(listener == NULL)
return NULL;
#ifdef IPV6
if(listener->addr.ss_family == AF_INET6)
port = ntohs(((const struct sockaddr_in6 *)&listener->addr)->sin6_port);
else
#endif
port = ntohs(((const struct sockaddr_in *)&listener->addr)->sin_port);
ircsnprintf(buf, sizeof(buf), "%s[%s/%u]", me.name, listener->name, port);
return buf;
}
/*
* show_ports - send port listing to a client
* inputs - pointer to client to show ports to
* output - none
* side effects - show ports
*/
void
show_ports(struct Client *source_p)
{
listener_t *listener = 0;
for (listener = ListenerPollList; listener; listener = listener->next)
{
sendto_one_numeric(source_p, RPL_STATSPLINE,
form_str(RPL_STATSPLINE), 'P',
#ifdef IPV6
ntohs(listener->addr.ss_family == AF_INET ? ((struct sockaddr_in *)&listener->addr)->sin_port :
((struct sockaddr_in6 *)&listener->addr)->sin6_port),
#else
ntohs(((struct sockaddr_in *)&listener->addr)->sin_port),
#endif
IsOperAdmin(source_p) ? listener->name : me.name,
listener->ref_count, (listener->active) ? "active" : "disabled");
}
}
/*
* inetport - create a listener socket in the AF_INET or AF_INET6 domain,
* bind it to the port given in 'port' and listen to it
* returns true (1) if successful false (0) on error.
*
* If the operating system has a define for SOMAXCONN, use it, otherwise
* use RATBOX_SOMAXCONN
*/
#ifdef SOMAXCONN
#undef RATBOX_SOMAXCONN
#define RATBOX_SOMAXCONN SOMAXCONN
#endif
static int
inetport(listener_t *listener)
{
int fd;
int opt = 1;
/*
* At first, open a new socket
*/
fd = comm_socket(listener->addr.ss_family, SOCK_STREAM, 0, "Listener socket");
#ifdef IPV6
if(listener->addr.ss_family == AF_INET6)
{
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&listener->addr;
if(!IN6_ARE_ADDR_EQUAL(&in6->sin6_addr, &in6addr_any))
{
inetntop(AF_INET6, &in6->sin6_addr, listener->vhost, sizeof(listener->vhost));
listener->name = listener->vhost;
}
} else
#endif
{
struct sockaddr_in *in = (struct sockaddr_in *)&listener->addr;
if(in->sin_addr.s_addr != INADDR_ANY)
{
inetntop(AF_INET, &in->sin_addr, listener->vhost, sizeof(listener->vhost));
listener->name = listener->vhost;
}
}
/*
* At one point, we enforced a strange arbitrary limit here.
* We no longer do this, and just check if the fd is valid or not.
* -nenolod
*/
if(fd == -1)
{
report_error("opening listener socket %s:%s",
get_listener_name(listener),
get_listener_name(listener), errno);
return 0;
}
/*
* XXX - we don't want to do all this crap for a listener
* set_sock_opts(listener);
*/
if(setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *) &opt, sizeof(opt)))
{
report_error("setting SO_REUSEADDR for listener %s:%s",
get_listener_name(listener),
get_listener_name(listener), errno);
comm_close(fd);
return 0;
}
/*
* Bind a port to listen for new connections if port is non-null,
* else assume it is already open and try get something from it.
*/
if(bind(fd, (struct sockaddr *) &listener->addr, GET_SS_LEN(listener->addr)))
{
report_error("binding listener socket %s:%s",
get_listener_name(listener),
get_listener_name(listener), errno);
comm_close(fd);
return 0;
}
if(listen(fd, RATBOX_SOMAXCONN))
{
report_error("listen failed for %s:%s",
get_listener_name(listener),
get_listener_name(listener), errno);
comm_close(fd);
return 0;
}
listener->fd = fd;
/* Listen completion events are READ events .. */
accept_connection(fd, listener);
return 1;
}
static listener_t *
find_listener(struct irc_sockaddr_storage *addr)
{
listener_t *listener = NULL;
listener_t *last_closed = NULL;
for (listener = ListenerPollList; listener; listener = listener->next)
{
if(addr->ss_family != listener->addr.ss_family)
continue;
switch(addr->ss_family)
{
case AF_INET:
{
struct sockaddr_in *in4 = (struct sockaddr_in *)addr;
struct sockaddr_in *lin4 = (struct sockaddr_in *)&listener->addr;
if(in4->sin_addr.s_addr == lin4->sin_addr.s_addr &&
in4->sin_port == lin4->sin_port )
{
if(listener->fd == -1)
last_closed = listener;
else
return(listener);
}
break;
}
#ifdef IPV6
case AF_INET6:
{
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)addr;
struct sockaddr_in6 *lin6 =(struct sockaddr_in6 *)&listener->addr;
if(IN6_ARE_ADDR_EQUAL(&in6->sin6_addr, &lin6->sin6_addr) &&
in6->sin6_port == lin6->sin6_port)
{
if(listener->fd == -1)
last_closed = listener;
else
return(listener);
}
break;
}
#endif
default:
break;
}
}
return last_closed;
}
/*
* add_listener- create a new listener
* port - the port number to listen on
* vhost_ip - if non-null must contain a valid IP address string in
* the format "255.255.255.255"
*/
void
add_listener(int port, const char *vhost_ip, int family)
{
listener_t *listener;
struct irc_sockaddr_storage vaddr;
/*
* if no port in conf line, don't bother
*/
if(port == 0)
return;
memset(&vaddr, 0, sizeof(vaddr));
vaddr.ss_family = family;
if(vhost_ip != NULL)
{
if(family == AF_INET)
{
if(inetpton(family, vhost_ip, &((struct sockaddr_in *)&vaddr)->sin_addr) <= 0)
return;
}
#ifdef IPV6
else
{
if(inetpton(family, vhost_ip, &((struct sockaddr_in6 *)&vaddr)->sin6_addr) <= 0)
return;
}
#endif
} else
{
switch(family)
{
case AF_INET:
((struct sockaddr_in *)&vaddr)->sin_addr.s_addr = INADDR_ANY;
break;
#ifdef IPV6
case AF_INET6:
memcpy(&((struct sockaddr_in6 *)&vaddr)->sin6_addr, &in6addr_any, sizeof(struct in6_addr));
break;
default:
return;
#endif
}
}
switch(family)
{
case AF_INET:
SET_SS_LEN(vaddr, sizeof(struct sockaddr_in));
((struct sockaddr_in *)&vaddr)->sin_port = htons(port);
break;
#ifdef IPV6
case AF_INET6:
SET_SS_LEN(vaddr, sizeof(struct sockaddr_in6));
((struct sockaddr_in6 *)&vaddr)->sin6_port = htons(port);
break;
#endif
default:
break;
}
if((listener = find_listener(&vaddr)))
{
if(listener->fd > -1)
return;
}
else
{
listener = make_listener(&vaddr);
listener->next = ListenerPollList;
ListenerPollList = listener;
}
listener->fd = -1;
if(inetport(listener))
listener->active = 1;
else
close_listener(listener);
}
/*
* close_listener - close a single listener
*/
void
close_listener(listener_t *listener)
{
s_assert(listener != NULL);
if(listener == NULL)
return;
if(listener->fd >= 0)
{
comm_close(listener->fd);
listener->fd = -1;
}
listener->active = 0;
if(listener->ref_count)
return;
free_listener(listener);
}
/*
* close_listeners - close and free all listeners that are not being used
*/
void
close_listeners()
{
listener_t *listener;
listener_t *listener_next = 0;
/*
* close all 'extra' listening ports we have
*/
for (listener = ListenerPollList; listener; listener = listener_next)
{
listener_next = listener->next;
close_listener(listener);
}
}
#define DLINE_WARNING "ERROR :You have been D-lined.\r\n"
/*
* add_connection - creates a client which has just connected to us on
* the given fd. The sockhost field is initialized with the ip# of the host.
* The client is sent to the auth module for verification, and not put in
* any client list yet.
*/
static void
add_connection(listener_t *listener, int fd, struct sockaddr *sai)
{
struct Client *new_client;
s_assert(NULL != listener);
/*
* get the client socket name from the socket
* the client has already been checked out in accept_connection
*/
new_client = make_client(NULL);
memcpy(&new_client->localClient->ip, sai, sizeof(struct irc_sockaddr_storage));
/*
* copy address to 'sockhost' as a string, copy it to host too
* so we have something valid to put into error messages...
*/
inetntop_sock((struct sockaddr *)&new_client->localClient->ip, new_client->sockhost,
sizeof(new_client->sockhost));
strlcpy(new_client->host, new_client->sockhost, sizeof(new_client->host));
#ifdef IPV6
if(new_client->localClient->ip.ss_family == AF_INET6 && ConfigFileEntry.dot_in_ip6_addr == 1)
{
strlcat(new_client->host, ".", sizeof(new_client->host));
}
#endif
new_client->localClient->fd = fd;
new_client->localClient->listener = listener;
++listener->ref_count;
if(check_reject(new_client))
return;
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if(add_unknown_ip(new_client))
return;
start_auth(new_client);
}
static void
accept_connection(int pfd, void *data)
{
static time_t last_oper_notice = 0;
struct irc_sockaddr_storage sai;
socklen_t addrlen = sizeof(sai);
int fd;
listener_t *listener = data;
struct ConfItem *aconf;
char buf[BUFSIZE];
s_assert(listener != NULL);
if(listener == NULL)
return;
/*
* There may be many reasons for error return, but
* in otherwise correctly working environment the
* probable cause is running out of file descriptors
* (EMFILE, ENFILE or others?). The man pages for
* accept don't seem to list these as possible,
* although it's obvious that it may happen here.
* Thus no specific errors are tested at this
* point, just assume that connections cannot
* be accepted until some old is closed first.
*/
fd = comm_accept(listener->fd, (struct sockaddr *)&sai, &addrlen);
if(fd < 0)
{
/* Re-register a new IO request for the next accept .. */
comm_setselect(listener->fd, FDLIST_SERVICE,
COMM_SELECT_READ, accept_connection, listener, 0);
return;
}
/* This needs to be done here, otherwise we break dlines */
mangle_mapped_sockaddr((struct sockaddr *)&sai);
/*
* check for connection limit
* TBD: this is stupid... either we have a socket or we don't. -nenolod
*/
if((comm_get_maxconnections() - 10) < fd)
{
++ServerStats->is_ref;
/*
* slow down the whining to opers bit
*/
if((last_oper_notice + 20) <= CurrentTime)
{
sendto_realops_snomask(SNO_GENERAL, L_ALL,
"All connections in use. (%s)",
get_listener_name(listener));
last_oper_notice = CurrentTime;
}
write(fd, "ERROR :All connections in use\r\n", 32);
comm_close(fd);
/* Re-register a new IO request for the next accept .. */
comm_setselect(listener->fd, FDLIST_SERVICE,
COMM_SELECT_READ, accept_connection, listener, 0);
return;
}
/* Do an initial check we aren't connecting too fast or with too many
* from this IP... */
if((aconf = conf_connect_allowed((struct sockaddr *)&sai, sai.ss_family)) != NULL)
{
ServerStats->is_ref++;
if(ConfigFileEntry.dline_with_reason)
{
if (ircsnprintf(buf, sizeof(buf), "ERROR :*** Banned: %s\r\n", aconf->passwd) >= (sizeof(buf)-1))
{
buf[sizeof(buf) - 3] = '\r';
buf[sizeof(buf) - 2] = '\n';
buf[sizeof(buf) - 1] = '\0';
}
}
else
ircsprintf(buf, "ERROR :You have been D-lined.\r\n");
write(fd, buf, strlen(buf));
comm_close(fd);
/* Re-register a new IO request for the next accept .. */
comm_setselect(listener->fd, FDLIST_SERVICE,
COMM_SELECT_READ, accept_connection, listener, 0);
return;
}
ServerStats->is_ac++;
add_connection(listener, fd, (struct sockaddr *)&sai);
/* Re-register a new IO request for the next accept .. */
comm_setselect(listener->fd, FDLIST_SERVICE, COMM_SELECT_READ,
accept_connection, listener, 0);
}