/* * 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 * * $Id: listener.c 3460 2007-05-18 20:31:33Z jilles $ */ #include "stdinc.h" #include "setup.h" #include "listener.h" #include "client.h" #include "match.h" #include "ircd.h" #include "ircd_defs.h" #include "numeric.h" #include "s_conf.h" #include "s_newconf.h" #include "s_stats.h" #include "send.h" #include "s_auth.h" #include "reject.h" #include "s_conf.h" #include "hostmask.h" #include "sslproc.h" #include "hash.h" #include "s_assert.h" #include "logger.h" #ifndef INADDR_NONE #define INADDR_NONE ((unsigned int) 0xffffffff) #endif #if defined(NO_IN6ADDR_ANY) && defined(RB_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 struct Listener *ListenerPollList = NULL; static int accept_precallback(rb_fde_t *F, struct sockaddr *addr, rb_socklen_t addrlen, void *data); static void accept_callback(rb_fde_t *F, int status, struct sockaddr *addr, rb_socklen_t addrlen, void *data); static struct Listener * make_listener(struct rb_sockaddr_storage *addr) { struct Listener *listener = (struct Listener *) rb_malloc(sizeof(struct Listener)); s_assert(0 != listener); listener->name = me.name; listener->F = NULL; memcpy(&listener->addr, addr, sizeof(struct rb_sockaddr_storage)); listener->next = NULL; return listener; } void free_listener(struct Listener *listener) { s_assert(NULL != listener); if(listener == NULL) return; /* * remove from listener list */ if(listener == ListenerPollList) ListenerPollList = listener->next; else { struct Listener *prev = ListenerPollList; for (; prev; prev = prev->next) { if(listener == prev->next) { prev->next = listener->next; break; } } } /* free */ rb_free(listener); } #define PORTNAMELEN 6 /* ":31337" */ /* * get_listener_port - return displayable listener port */ static uint16_t get_listener_port(const struct Listener *listener) { #ifdef RB_IPV6 if(listener->addr.ss_family == AF_INET6) return ntohs(((const struct sockaddr_in6 *)&listener->addr)->sin6_port); else #endif return ntohs(((const struct sockaddr_in *)&listener->addr)->sin_port); } /* * get_listener_name - return displayable listener name and port * returns "host.foo.org:6667" for a given listener */ const char * get_listener_name(const struct Listener *listener) { static char buf[HOSTLEN + HOSTLEN + PORTNAMELEN + 4]; s_assert(NULL != listener); if(listener == NULL) return NULL; rb_snprintf(buf, sizeof(buf), "%s[%s/%u]", me.name, listener->name, get_listener_port(listener)); 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) { struct Listener *listener = 0; for (listener = ListenerPollList; listener; listener = listener->next) { sendto_one_numeric(source_p, RPL_STATSPLINE, form_str(RPL_STATSPLINE), 'P', get_listener_port(listener), IsOperAdmin(source_p) ? listener->name : me.name, listener->ref_count, (listener->active) ? "active" : "disabled", listener->ssl ? " ssl" : ""); } } /* * 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(struct Listener *listener) { rb_fde_t *F; int opt = 1; const char *errstr; /* * At first, open a new socket */ F = rb_socket(GET_SS_FAMILY(&listener->addr), SOCK_STREAM, 0, "Listener socket"); #ifdef RB_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)) { rb_inet_ntop(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) { rb_inet_ntop(AF_INET, &in->sin_addr, listener->vhost, sizeof(listener->vhost)); listener->name = listener->vhost; } } if(F == NULL) { sendto_realops_snomask(SNO_GENERAL, L_ALL, "Cannot open socket for listener on port %d", get_listener_port(listener)); ilog(L_MAIN, "Cannot open socket for listener %s", get_listener_name(listener)); return 0; } else if((maxconnections - 10) < rb_get_fd(F)) /* XXX this is kinda bogus*/ { ilog_error("no more connections left for listener"); sendto_realops_snomask(SNO_GENERAL, L_ALL, "No more connections left for listener on port %d", get_listener_port(listener)); ilog(L_MAIN, "No more connections left for listener %s", get_listener_name(listener)); rb_close(F); return 0; } /* * XXX - we don't want to do all this crap for a listener * set_sock_opts(listener); */ if(setsockopt(rb_get_fd(F), SOL_SOCKET, SO_REUSEADDR, (char *) &opt, sizeof(opt))) { errstr = strerror(rb_get_sockerr(F)); sendto_realops_snomask(SNO_GENERAL, L_ALL, "Cannot set SO_REUSEADDR for listener on port %d: %s", get_listener_port(listener), errstr); ilog(L_MAIN, "Cannot set SO_REUSEADDR for listener %s: %s", get_listener_name(listener), errstr); rb_close(F); 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(rb_get_fd(F), (struct sockaddr *) &listener->addr, GET_SS_LEN(&listener->addr))) { errstr = strerror(rb_get_sockerr(F)); sendto_realops_snomask(SNO_GENERAL, L_ALL, "Cannot bind for listener on port %d: %s", get_listener_port(listener), errstr); ilog(L_MAIN, "Cannot bind for listener %s: %s", get_listener_name(listener), errstr); rb_close(F); return 0; } if(rb_listen(F, RATBOX_SOMAXCONN, listener->defer_accept)) { errstr = strerror(rb_get_sockerr(F)); sendto_realops_snomask(SNO_GENERAL, L_ALL, "Cannot listen() for listener on port %d: %s", get_listener_port(listener), errstr); ilog(L_MAIN, "Cannot listen() for listener %s: %s", get_listener_name(listener), errstr); rb_close(F); return 0; } listener->F = F; rb_accept_tcp(listener->F, accept_precallback, accept_callback, listener); return 1; } static struct Listener * find_listener(struct rb_sockaddr_storage *addr) { struct Listener *listener = NULL; struct Listener *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->F == NULL) last_closed = listener; else return(listener); } break; } #ifdef RB_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->F == NULL) 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, int ssl, int defer_accept) { struct Listener *listener; struct rb_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(rb_inet_pton(family, vhost_ip, &((struct sockaddr_in *)&vaddr)->sin_addr) <= 0) return; } #ifdef RB_IPV6 else { if(rb_inet_pton(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 RB_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 RB_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->F != NULL) return; } else { listener = make_listener(&vaddr); listener->next = ListenerPollList; ListenerPollList = listener; } listener->F = NULL; listener->ssl = ssl; listener->defer_accept = defer_accept; if(inetport(listener)) listener->active = 1; else close_listener(listener); } /* * close_listener - close a single listener */ void close_listener(struct Listener *listener) { s_assert(listener != NULL); if(listener == NULL) return; if(listener->F != NULL) { rb_close(listener->F); listener->F = NULL; } 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() { struct Listener *listener; struct Listener *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(struct Listener *listener, rb_fde_t *F, struct sockaddr *sai, struct sockaddr *lai) { 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); if (listener->ssl) { rb_fde_t *xF[2]; if(rb_socketpair(AF_UNIX, SOCK_STREAM, 0, &xF[0], &xF[1], "Incoming ssld Connection") == -1) { free_client(new_client); return; } new_client->localClient->ssl_ctl = start_ssld_accept(F, xF[1], new_client->localClient->connid); /* this will close F for us */ if(new_client->localClient->ssl_ctl == NULL) { free_client(new_client); return; } F = xF[0]; SetSSL(new_client); } memcpy(&new_client->localClient->ip, sai, sizeof(struct rb_sockaddr_storage)); memcpy(&new_client->preClient->lip, lai, sizeof(struct rb_sockaddr_storage)); /* * copy address to 'sockhost' as a string, copy it to host too * so we have something valid to put into error messages... */ rb_inet_ntop_sock((struct sockaddr *)&new_client->localClient->ip, new_client->sockhost, sizeof(new_client->sockhost)); rb_strlcpy(new_client->host, new_client->sockhost, sizeof(new_client->host)); new_client->localClient->F = F; new_client->localClient->listener = listener; ++listener->ref_count; start_auth(new_client); } static const char *toofast = "ERROR :Reconnecting too fast, throttled.\r\n"; static int accept_precallback(rb_fde_t *F, struct sockaddr *addr, rb_socklen_t addrlen, void *data) { struct Listener *listener = (struct Listener *)data; char buf[BUFSIZE]; struct ConfItem *aconf; static time_t last_oper_notice = 0; int len; if(listener->ssl && (!ssl_ok || !get_ssld_count())) { rb_close(F); return 0; } if((maxconnections - 10) < rb_get_fd(F)) /* XXX this is kinda bogus */ { ++ServerStats.is_ref; /* * slow down the whining to opers bit */ if((last_oper_notice + 20) <= rb_current_time()) { sendto_realops_snomask(SNO_GENERAL, L_ALL, "All connections in use. (%s)", get_listener_name(listener)); last_oper_notice = rb_current_time(); } rb_write(F, "ERROR :All connections in use\r\n", 31); rb_close(F); return 0; } aconf = find_dline(addr, addr->sa_family); if(aconf != NULL && (aconf->status & CONF_EXEMPTDLINE)) return 1; /* Do an initial check we aren't connecting too fast or with too many * from this IP... */ if(aconf != NULL) { ServerStats.is_ref++; if(ConfigFileEntry.dline_with_reason) { len = rb_snprintf(buf, sizeof(buf), "ERROR :*** Banned: %s\r\n", get_user_ban_reason(aconf)); if (len >= (int)(sizeof(buf)-1)) { buf[sizeof(buf) - 3] = '\r'; buf[sizeof(buf) - 2] = '\n'; buf[sizeof(buf) - 1] = '\0'; } } else strcpy(buf, "ERROR :You have been D-lined.\r\n"); rb_write(F, buf, strlen(buf)); rb_close(F); return 0; } if(check_reject(F, addr)) return 0; if(throttle_add(addr)) { rb_write(F, toofast, strlen(toofast)); rb_close(F); return 0; } return 1; } static void accept_callback(rb_fde_t *F, int status, struct sockaddr *addr, rb_socklen_t addrlen, void *data) { struct Listener *listener = data; struct rb_sockaddr_storage lip; unsigned int locallen = sizeof(struct rb_sockaddr_storage); ServerStats.is_ac++; if(getsockname(rb_get_fd(F), (struct sockaddr *) &lip, &locallen) < 0) { /* this can fail if the connection disappeared in the meantime */ rb_close(F); return; } add_connection(listener, F, addr, (struct sockaddr *)&lip); }