diff options
Diffstat (limited to 'src/s_bsd.c')
| -rw-r--r-- | src/s_bsd.c | 757 |
1 files changed, 757 insertions, 0 deletions
diff --git a/src/s_bsd.c b/src/s_bsd.c new file mode 100644 index 0000000..316d3f4 --- /dev/null +++ b/src/s_bsd.c @@ -0,0 +1,757 @@ +/* + * ircd-hybrid: an advanced Internet Relay Chat Daemon(ircd). + * s_bsd.c: Network functions. + * + * Copyright (C) 2002 by the past and present ircd coders, and others. + * + * 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 + * + * $Id$ + */ + +#include "stdinc.h" +#include <netinet/in_systm.h> +#include <netinet/ip.h> +#include <netinet/tcp.h> +#include "list.h" +#include "fdlist.h" +#include "s_bsd.h" +#include "client.h" +#include "dbuf.h" +#include "event.h" +#include "irc_string.h" +#include "ircd.h" +#include "listener.h" +#include "numeric.h" +#include "packet.h" +#include "irc_res.h" +#include "restart.h" +#include "s_auth.h" +#include "conf.h" +#include "log.h" +#include "s_serv.h" +#include "send.h" +#include "memory.h" +#include "s_user.h" +#include "hook.h" + +static const char *comm_err_str[] = { "Comm OK", "Error during bind()", + "Error during DNS lookup", "connect timeout", "Error during connect()", + "Comm Error" }; + +struct Callback *setup_socket_cb = NULL; + +static void comm_connect_callback(fde_t *, int); +static PF comm_connect_timeout; +static void comm_connect_dns_callback(void *, const struct irc_ssaddr *, const char *); +static PF comm_connect_tryconnect; + + +/* check_can_use_v6() + * Check if the system can open AF_INET6 sockets + */ +void +check_can_use_v6(void) +{ +#ifdef IPV6 + int v6; + + if ((v6 = socket(AF_INET6, SOCK_STREAM, 0)) < 0) + ServerInfo.can_use_v6 = 0; + else + { + ServerInfo.can_use_v6 = 1; + close(v6); + } +#else + ServerInfo.can_use_v6 = 0; +#endif +} + +/* get_sockerr - get the error value from the socket or the current errno + * + * Get the *real* error from the socket (well try to anyway..). + * This may only work when SO_DEBUG is enabled but its worth the + * gamble anyway. + */ +int +get_sockerr(int fd) +{ + int errtmp = errno; +#ifdef SO_ERROR + int err = 0; + socklen_t len = sizeof(err); + + if (-1 < fd && !getsockopt(fd, SOL_SOCKET, SO_ERROR, &err, &len)) + { + if (err) + errtmp = err; + } + errno = errtmp; +#endif + return errtmp; +} + +/* + * report_error - report an error from an errno. + * Record error to log and also send a copy to all *LOCAL* opers online. + * + * text is a *format* string for outputing error. It must + * contain only two '%s', the first will be replaced + * by the sockhost from the client_p, and the latter will + * be taken from sys_errlist[errno]. + * + * client_p if not NULL, is the *LOCAL* client associated with + * the error. + * + * Cannot use perror() within daemon. stderr is closed in + * ircd and cannot be used. And, worse yet, it might have + * been reassigned to a normal connection... + * + * Actually stderr is still there IFF ircd was run with -s --Rodder + */ + +void +report_error(int level, const char* text, const char* who, int error) +{ + who = (who) ? who : ""; + + sendto_realops_flags(UMODE_DEBUG, level, text, who, strerror(error)); + ilog(LOG_TYPE_IRCD, text, who, strerror(error)); +} + +/* + * setup_socket() + * + * Set the socket non-blocking, and other wonderful bits. + */ +static void * +setup_socket(va_list args) +{ + int fd = va_arg(args, int); + int opt = 1; + + setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof(opt)); + +#ifdef IPTOS_LOWDELAY + opt = IPTOS_LOWDELAY; + setsockopt(fd, IPPROTO_IP, IP_TOS, &opt, sizeof(opt)); +#endif + + fcntl(fd, F_SETFL, fcntl(fd, F_GETFL, 0) | O_NONBLOCK); + + return NULL; +} + +/* + * init_comm() + * + * Initializes comm subsystem. + */ +void +init_comm(void) +{ + setup_socket_cb = register_callback("setup_socket", setup_socket); + init_netio(); +} + +/* + * close_connection + * Close the physical connection. This function must make + * MyConnect(client_p) == FALSE, and set client_p->from == NULL. + */ +void +close_connection(struct Client *client_p) +{ + struct AccessItem *aconf; + struct ClassItem *aclass; + dlink_node *ptr = NULL; + + assert(client_p); + + if (!IsDead(client_p)) + { + /* attempt to flush any pending dbufs. Evil, but .. -- adrian */ + /* there is still a chance that we might send data to this socket + * even if it is marked as blocked (COMM_SELECT_READ handler is called + * before COMM_SELECT_WRITE). Let's try, nothing to lose.. -adx + */ + ClearSendqBlocked(client_p); + send_queued_write(client_p); + } + + if (IsClient(client_p)) + { + ++ServerStats.is_cl; + ServerStats.is_cbs += client_p->localClient->send.bytes; + ServerStats.is_cbr += client_p->localClient->recv.bytes; + ServerStats.is_cti += CurrentTime - client_p->localClient->firsttime; + } + else if (IsServer(client_p)) + { + ++ServerStats.is_sv; + ServerStats.is_sbs += client_p->localClient->send.bytes; + ServerStats.is_sbr += client_p->localClient->recv.bytes; + ServerStats.is_sti += CurrentTime - client_p->localClient->firsttime; + + DLINK_FOREACH(ptr, server_items.head) + { + struct ConfItem *conf = ptr->data; + + if (irccmp(conf->name, client_p->name)) + continue; + + /* + * Reset next-connect cycle of all connect{} blocks that match + * this servername. + */ + aconf = map_to_conf(conf); + aclass = map_to_conf(aconf->class_ptr); + aconf->hold = CurrentTime + aclass->con_freq; + } + } + else + ++ServerStats.is_ni; + +#ifdef HAVE_LIBCRYPTO + if (client_p->localClient->fd.ssl) + { + SSL_set_shutdown(client_p->localClient->fd.ssl, SSL_RECEIVED_SHUTDOWN); + + if (!SSL_shutdown(client_p->localClient->fd.ssl)) + SSL_shutdown(client_p->localClient->fd.ssl); + } +#endif + if (client_p->localClient->fd.flags.open) + fd_close(&client_p->localClient->fd); + + dbuf_clear(&client_p->localClient->buf_sendq); + dbuf_clear(&client_p->localClient->buf_recvq); + + MyFree(client_p->localClient->passwd); + detach_conf(client_p, CONF_TYPE); + client_p->from = NULL; /* ...this should catch them! >:) --msa */ +} + +#ifdef HAVE_LIBCRYPTO +/* + * ssl_handshake - let OpenSSL initialize the protocol. Register for + * read/write events if necessary. + */ +static void +ssl_handshake(int fd, struct Client *client_p) +{ + int ret = SSL_accept(client_p->localClient->fd.ssl); + + if (ret <= 0) + switch (SSL_get_error(client_p->localClient->fd.ssl, ret)) + { + case SSL_ERROR_WANT_WRITE: + comm_setselect(&client_p->localClient->fd, COMM_SELECT_WRITE, + (PF *) ssl_handshake, client_p, 0); + return; + + case SSL_ERROR_WANT_READ: + comm_setselect(&client_p->localClient->fd, COMM_SELECT_READ, + (PF *) ssl_handshake, client_p, 0); + return; + + default: + exit_client(client_p, client_p, "Error during SSL handshake"); + return; + } + + execute_callback(auth_cb, client_p); +} +#endif + +/* + * 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. + * An unique id is calculated now, in case it is needed for auth. + * The client is sent to the auth module for verification, and not put in + * any client list yet. + */ +void +add_connection(struct Listener *listener, struct irc_ssaddr *irn, int fd) +{ + struct Client *new_client = make_client(NULL); + + fd_open(&new_client->localClient->fd, fd, 1, + (listener->flags & LISTENER_SSL) ? + "Incoming SSL connection" : "Incoming connection"); + + /* + * copy address to 'sockhost' as a string, copy it to host too + * so we have something valid to put into error messages... + */ + memcpy(&new_client->localClient->ip, irn, sizeof(struct irc_ssaddr)); + + getnameinfo((struct sockaddr *)&new_client->localClient->ip, + new_client->localClient->ip.ss_len, new_client->sockhost, + sizeof(new_client->sockhost), NULL, 0, NI_NUMERICHOST); + new_client->localClient->aftype = new_client->localClient->ip.ss.ss_family; + + if (new_client->sockhost[0] == ':' && new_client->sockhost[1] == ':') + { + strlcpy(new_client->host, "0", sizeof(new_client->host)); + strlcpy(new_client->host+1, new_client->sockhost, sizeof(new_client->host)-1); + memmove(new_client->sockhost+1, new_client->sockhost, sizeof(new_client->sockhost)-1); + new_client->sockhost[0] = '0'; + } + else + strlcpy(new_client->host, new_client->sockhost, sizeof(new_client->host)); + + new_client->localClient->listener = listener; + ++listener->ref_count; + +#ifdef HAVE_LIBCRYPTO + if (listener->flags & LISTENER_SSL) + { + if ((new_client->localClient->fd.ssl = SSL_new(ServerInfo.server_ctx)) == NULL) + { + ilog(LOG_TYPE_IRCD, "SSL_new() ERROR! -- %s", + ERR_error_string(ERR_get_error(), NULL)); + + SetDead(new_client); + exit_client(new_client, new_client, "SSL_new failed"); + return; + } + + SSL_set_fd(new_client->localClient->fd.ssl, fd); + ssl_handshake(0, new_client); + } + else +#endif + execute_callback(auth_cb, new_client); +} + +/* + * stolen from squid - its a neat (but overused! :) routine which we + * can use to see whether we can ignore this errno or not. It is + * generally useful for non-blocking network IO related errnos. + * -- adrian + */ +int +ignoreErrno(int ierrno) +{ + switch (ierrno) + { + case EINPROGRESS: + case EWOULDBLOCK: +#if EAGAIN != EWOULDBLOCK + case EAGAIN: +#endif + case EALREADY: + case EINTR: +#ifdef ERESTART + case ERESTART: +#endif + return 1; + default: + return 0; + } +} + +/* + * comm_settimeout() - set the socket timeout + * + * Set the timeout for the fd + */ +void +comm_settimeout(fde_t *fd, time_t timeout, PF *callback, void *cbdata) +{ + assert(fd->flags.open); + + fd->timeout = CurrentTime + (timeout / 1000); + fd->timeout_handler = callback; + fd->timeout_data = cbdata; +} + +/* + * comm_setflush() - set a flush function + * + * A flush function is simply a function called if found during + * comm_timeouts(). Its basically a second timeout, except in this case + * I'm too lazy to implement multiple timeout functions! :-) + * its kinda nice to have it separate, since this is designed for + * flush functions, and when comm_close() is implemented correctly + * with close functions, we _actually_ don't call comm_close() here .. + * -- originally Adrian's notes + * comm_close() is replaced with fd_close() in fdlist.c + */ +void +comm_setflush(fde_t *fd, time_t timeout, PF *callback, void *cbdata) +{ + assert(fd->flags.open); + + fd->flush_timeout = CurrentTime + (timeout / 1000); + fd->flush_handler = callback; + fd->flush_data = cbdata; +} + +/* + * comm_checktimeouts() - check the socket timeouts + * + * All this routine does is call the given callback/cbdata, without closing + * down the file descriptor. When close handlers have been implemented, + * this will happen. + */ +void +comm_checktimeouts(void *notused) +{ + int i; + fde_t *F; + PF *hdl; + void *data; + + for (i = 0; i < FD_HASH_SIZE; i++) + for (F = fd_hash[i]; F != NULL; F = fd_next_in_loop) + { + assert(F->flags.open); + fd_next_in_loop = F->hnext; + + /* check flush functions */ + if (F->flush_handler && F->flush_timeout > 0 && + F->flush_timeout < CurrentTime) + { + hdl = F->flush_handler; + data = F->flush_data; + comm_setflush(F, 0, NULL, NULL); + hdl(F, data); + } + + /* check timeouts */ + if (F->timeout_handler && F->timeout > 0 && + F->timeout < CurrentTime) + { + /* Call timeout handler */ + hdl = F->timeout_handler; + data = F->timeout_data; + comm_settimeout(F, 0, NULL, NULL); + hdl(F, data); + } + } +} + +/* + * void comm_connect_tcp(int fd, const char *host, unsigned short port, + * struct sockaddr *clocal, int socklen, + * CNCB *callback, void *data, int aftype, int timeout) + * Input: An fd to connect with, a host and port to connect to, + * a local sockaddr to connect from + length(or NULL to use the + * default), a callback, the data to pass into the callback, the + * address family. + * Output: None. + * Side-effects: A non-blocking connection to the host is started, and + * if necessary, set up for selection. The callback given + * may be called now, or it may be called later. + */ +void +comm_connect_tcp(fde_t *fd, const char *host, unsigned short port, + struct sockaddr *clocal, int socklen, CNCB *callback, + void *data, int aftype, int timeout) +{ + struct addrinfo hints, *res; + char portname[PORTNAMELEN + 1]; + + assert(callback); + fd->connect.callback = callback; + fd->connect.data = data; + + fd->connect.hostaddr.ss.ss_family = aftype; + fd->connect.hostaddr.ss_port = htons(port); + + /* Note that we're using a passed sockaddr here. This is because + * generally you'll be bind()ing to a sockaddr grabbed from + * getsockname(), so this makes things easier. + * XXX If NULL is passed as local, we should later on bind() to the + * virtual host IP, for completeness. + * -- adrian + */ + if ((clocal != NULL) && (bind(fd->fd, clocal, socklen) < 0)) + { + /* Failure, call the callback with COMM_ERR_BIND */ + comm_connect_callback(fd, COMM_ERR_BIND); + /* ... and quit */ + return; + } + + /* Next, if we have been given an IP, get the addr and skip the + * DNS check (and head direct to comm_connect_tryconnect(). + */ + memset(&hints, 0, sizeof(hints)); + hints.ai_family = AF_UNSPEC; + hints.ai_socktype = SOCK_STREAM; + hints.ai_flags = AI_PASSIVE | AI_NUMERICHOST; + + snprintf(portname, sizeof(portname), "%d", port); + + if (getaddrinfo(host, portname, &hints, &res)) + { + /* Send the DNS request, for the next level */ + if (aftype == AF_INET6) + gethost_byname_type(comm_connect_dns_callback, fd, host, T_AAAA); + else + gethost_byname_type(comm_connect_dns_callback, fd, host, T_A); + } + else + { + /* We have a valid IP, so we just call tryconnect */ + /* Make sure we actually set the timeout here .. */ + assert(res != NULL); + memcpy(&fd->connect.hostaddr, res->ai_addr, res->ai_addrlen); + fd->connect.hostaddr.ss_len = res->ai_addrlen; + fd->connect.hostaddr.ss.ss_family = res->ai_family; + freeaddrinfo(res); + comm_settimeout(fd, timeout*1000, comm_connect_timeout, NULL); + comm_connect_tryconnect(fd, NULL); + } +} + +/* + * comm_connect_callback() - call the callback, and continue with life + */ +static void +comm_connect_callback(fde_t *fd, int status) +{ + CNCB *hdl; + + /* This check is gross..but probably necessary */ + if (fd->connect.callback == NULL) + return; + + /* Clear the connect flag + handler */ + hdl = fd->connect.callback; + fd->connect.callback = NULL; + + /* Clear the timeout handler */ + comm_settimeout(fd, 0, NULL, NULL); + + /* Call the handler */ + hdl(fd, status, fd->connect.data); +} + +/* + * comm_connect_timeout() - this gets called when the socket connection + * times out. This *only* can be called once connect() is initially + * called .. + */ +static void +comm_connect_timeout(fde_t *fd, void *notused) +{ + /* error! */ + comm_connect_callback(fd, COMM_ERR_TIMEOUT); +} + +/* + * comm_connect_dns_callback() - called at the completion of the DNS request + * + * The DNS request has completed, so if we've got an error, return it, + * otherwise we initiate the connect() + */ +static void +comm_connect_dns_callback(void *vptr, const struct irc_ssaddr *addr, const char *name) +{ + fde_t *F = vptr; + + if (name == NULL) + { + comm_connect_callback(F, COMM_ERR_DNS); + return; + } + + /* No error, set a 10 second timeout */ + comm_settimeout(F, 30*1000, comm_connect_timeout, NULL); + + /* Copy over the DNS reply info so we can use it in the connect() */ + /* + * Note we don't fudge the refcount here, because we aren't keeping + * the DNS record around, and the DNS cache is gone anyway.. + * -- adrian + */ + memcpy(&F->connect.hostaddr, addr, addr->ss_len); + /* The cast is hacky, but safe - port offset is same on v4 and v6 */ + ((struct sockaddr_in *) &F->connect.hostaddr)->sin_port = + F->connect.hostaddr.ss_port; + F->connect.hostaddr.ss_len = addr->ss_len; + + /* Now, call the tryconnect() routine to try a connect() */ + comm_connect_tryconnect(F, NULL); +} + +/* static void comm_connect_tryconnect(int fd, void *notused) + * Input: The fd, the handler data(unused). + * Output: None. + * Side-effects: Try and connect with pending connect data for the FD. If + * we succeed or get a fatal error, call the callback. + * Otherwise, it is still blocking or something, so register + * to select for a write event on this FD. + */ +static void +comm_connect_tryconnect(fde_t *fd, void *notused) +{ + int retval; + + /* This check is needed or re-entrant s_bsd_* like sigio break it. */ + if (fd->connect.callback == NULL) + return; + + /* Try the connect() */ + retval = connect(fd->fd, (struct sockaddr *) &fd->connect.hostaddr, + fd->connect.hostaddr.ss_len); + + /* Error? */ + if (retval < 0) + { + /* + * If we get EISCONN, then we've already connect()ed the socket, + * which is a good thing. + * -- adrian + */ + if (errno == EISCONN) + comm_connect_callback(fd, COMM_OK); + else if (ignoreErrno(errno)) + /* Ignore error? Reschedule */ + comm_setselect(fd, COMM_SELECT_WRITE, comm_connect_tryconnect, + NULL, 0); + else + /* Error? Fail with COMM_ERR_CONNECT */ + comm_connect_callback(fd, COMM_ERR_CONNECT); + return; + } + + /* If we get here, we've suceeded, so call with COMM_OK */ + comm_connect_callback(fd, COMM_OK); +} + +/* + * comm_errorstr() - return an error string for the given error condition + */ +const char * +comm_errstr(int error) +{ + if (error < 0 || error >= COMM_ERR_MAX) + return "Invalid error number!"; + return comm_err_str[error]; +} + +/* + * comm_open() - open a socket + * + * This is a highly highly cut down version of squid's comm_open() which + * for the most part emulates socket(), *EXCEPT* it fails if we're about + * to run out of file descriptors. + */ +int +comm_open(fde_t *F, int family, int sock_type, int proto, const char *note) +{ + int fd; + + /* First, make sure we aren't going to run out of file descriptors */ + if (number_fd >= hard_fdlimit) + { + errno = ENFILE; + return -1; + } + + /* + * Next, we try to open the socket. We *should* drop the reserved FD + * limit if/when we get an error, but we can deal with that later. + * XXX !!! -- adrian + */ + fd = socket(family, sock_type, proto); + if (fd < 0) + return -1; /* errno will be passed through, yay.. */ + + execute_callback(setup_socket_cb, fd); + + /* update things in our fd tracking */ + fd_open(F, fd, 1, note); + return 0; +} + +/* + * comm_accept() - accept an incoming connection + * + * This is a simple wrapper for accept() which enforces FD limits like + * comm_open() does. Returned fd must be either closed or tagged with + * fd_open (this function no longer does it). + */ +int +comm_accept(struct Listener *lptr, struct irc_ssaddr *pn) +{ + int newfd; + socklen_t addrlen = sizeof(struct irc_ssaddr); + + if (number_fd >= hard_fdlimit) + { + errno = ENFILE; + return -1; + } + + /* + * Next, do the accept(). if we get an error, we should drop the + * reserved fd limit, but we can deal with that when comm_open() + * also does it. XXX -- adrian + */ + newfd = accept(lptr->fd.fd, (struct sockaddr *)pn, &addrlen); + if (newfd < 0) + return -1; + +#ifdef IPV6 + remove_ipv6_mapping(pn); +#else + pn->ss_len = addrlen; +#endif + + execute_callback(setup_socket_cb, newfd); + + /* .. and return */ + return newfd; +} + +/* + * remove_ipv6_mapping() - Removes IPv4-In-IPv6 mapping from an address + * OSes with IPv6 mapping listening on both + * AF_INET and AF_INET6 map AF_INET connections inside AF_INET6 structures + * + */ +#ifdef IPV6 +void +remove_ipv6_mapping(struct irc_ssaddr *addr) +{ + if (addr->ss.ss_family == AF_INET6) + { + if (IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)addr)->sin6_addr)) + { + struct sockaddr_in6 v6; + struct sockaddr_in *v4 = (struct sockaddr_in *)addr; + + memcpy(&v6, addr, sizeof(v6)); + memset(v4, 0, sizeof(struct sockaddr_in)); + memcpy(&v4->sin_addr, &v6.sin6_addr.s6_addr[12], sizeof(v4->sin_addr)); + + addr->ss.ss_family = AF_INET; + addr->ss_len = sizeof(struct sockaddr_in); + } + else + addr->ss_len = sizeof(struct sockaddr_in6); + } + else + addr->ss_len = sizeof(struct sockaddr_in); +} +#endif |