elemental-ircd/libcharybdis/commio.c

892 lines
20 KiB
C
Raw Normal View History

/*
* ircd-ratbox: A slightly useful ircd.
* commio.c: Network/file related functions
*
* 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: commio.c 3354 2007-04-03 09:21:31Z nenolod $
*/
#include "libcharybdis.h"
#ifndef IN_LOOPBACKNET
#define IN_LOOPBACKNET 0x7f
#endif
#ifndef INADDR_NONE
#define INADDR_NONE ((unsigned int) 0xffffffff)
#endif
const char *const NONB_ERROR_MSG = "set_non_blocking failed for %s:%s";
const char *const SETBUF_ERROR_MSG = "set_sock_buffers failed for server %s:%s";
static const char *comm_err_str[] = { "Comm OK", "Error during bind()",
"Error during DNS lookup", "connect timeout",
"Error during connect()",
"Comm Error"
};
#define FD_HASH_SIZE 128
static dlink_list fd_table[FD_HASH_SIZE];
static void fdlist_update_biggest(int fd, int opening);
/* Highest FD and number of open FDs .. */
int highest_fd = -1; /* Its -1 because we haven't started yet -- adrian */
int number_fd = 0;
static void comm_connect_callback(int fd, int status);
static PF comm_connect_timeout;
static void comm_connect_dns_callback(void *vptr, struct DNSReply *reply);
static PF comm_connect_tryconnect;
static int comm_max_connections = 0;
inline fde_t *
comm_locate_fd(int fd)
{
int bucket = fd % FD_HASH_SIZE;
dlink_list *list = &fd_table[bucket];
dlink_node *n;
DLINK_FOREACH(n, list->head)
{
fde_t *F = (fde_t *) n->data;
if (F->fd == fd)
return F;
}
return NULL;
}
inline fde_t *
comm_add_fd(int fd)
{
fde_t *F = comm_locate_fd(fd);
dlink_list *list;
if (F != NULL)
return F;
F = MyMalloc(sizeof(fde_t));
F->fd = fd;
F->read_impl = read;
F->write_impl = write;
list = &fd_table[fd % FD_HASH_SIZE];
dlinkAdd(F, &F->node, list);
return F;
}
inline void
comm_remove_fd(int fd)
{
int bucket = fd % FD_HASH_SIZE;
fde_t *F;
dlink_list *list = &fd_table[bucket];
F = comm_locate_fd(fd);
if (F == NULL)
return;
dlinkDelete(&F->node, list);
MyFree(F);
}
/* 32bit solaris is kinda slow and stdio only supports fds < 256
* so we got to do this crap below.
* (BTW Fuck you Sun, I hate your guts and I hope you go bankrupt soon)
* XXX: this is no longer needed in Solaris 10. --nenolod
*/
#if defined (__SVR4) && defined (__sun)
static void comm_fd_hack(int *fd)
{
int newfd;
if(*fd > 256 || *fd < 0)
return;
if((newfd = fcntl(*fd, F_DUPFD, 256)) != -1)
{
close(*fd);
*fd = newfd;
}
return;
}
#else
#define comm_fd_hack(fd)
#endif
/* close_all_connections() can be used *before* the system come up! */
void
comm_close_all(void)
{
int i;
#ifndef NDEBUG
int fd;
#endif
/*
* we start at 4 to avoid giving fds where malloc messages
* could be written --nenolod
*/
for (i = 4; i < comm_max_connections; ++i)
{
fde_t *F = comm_locate_fd(i);
if(F != NULL && F->flags.open)
comm_close(i);
else
close(i);
}
/* XXX should his hack be done in all cases? */
#ifndef NDEBUG
/* fugly hack to reserve fd == 2 */
(void) close(2);
fd = open("stderr.log", O_WRONLY | O_CREAT | O_APPEND, 0644);
if(fd >= 0)
{
dup2(fd, 2);
close(fd);
}
#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
comm_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, (char *) &err, (socklen_t *) & len))
{
if(err)
errtmp = err;
}
errno = errtmp;
#endif
return errtmp;
}
/*
* set_sock_buffers - set send and receive buffers for socket
*
* inputs - fd file descriptor
* - size to set
* output - returns true (1) if successful, false (0) otherwise
* side effects -
*/
int
comm_set_buffers(int fd, int size)
{
if(setsockopt
(fd, SOL_SOCKET, SO_RCVBUF, (char *) &size, sizeof(size))
|| setsockopt(fd, SOL_SOCKET, SO_SNDBUF, (char *) &size, sizeof(size)))
return 0;
return 1;
}
/*
* set_non_blocking - Set the client connection into non-blocking mode.
*
* inputs - fd to set into non blocking mode
* output - 1 if successful 0 if not
* side effects - use POSIX compliant non blocking and
* be done with it.
*/
int
comm_set_nb(int fd)
{
int nonb = 0;
int res;
fde_t *F = comm_locate_fd(fd);
nonb |= O_NONBLOCK;
res = fcntl(fd, F_GETFL, 0);
if(-1 == res || fcntl(fd, F_SETFL, res | nonb) == -1)
return 0;
if (F != NULL)
F->flags.nonblocking = 1;
return 1;
}
/*
* 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(int fd, time_t timeout, PF * callback, void *cbdata)
{
fde_t *F;
s_assert(fd >= 0);
F = comm_locate_fd(fd);
s_assert(F->flags.open);
F->timeout = CurrentTime + (timeout / 1000);
F->timeout_handler = callback;
F->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 seperate, 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 ..
*/
void
comm_setflush(int fd, time_t timeout, PF * callback, void *cbdata)
{
fde_t *F;
s_assert(fd >= 0);
F = comm_locate_fd(fd);
s_assert(F->flags.open);
F->flush_timeout = CurrentTime + (timeout / 1000);
F->flush_handler = callback;
F->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)
{
PF *hdl;
void *data;
fde_t *F;
dlink_list *bucket;
int i;
dlink_node *n, *n2;
2007-03-05 17:35:17 +00:00
for (i = 0; i <= FD_HASH_SIZE; i++)
{
bucket = &fd_table[i];
if (dlink_list_length(bucket) <= 0)
continue;
DLINK_FOREACH_SAFE(n, n2, bucket->head)
{
F = (fde_t *) n->data;
if(F == NULL)
continue;
if(!F->flags.open)
continue;
if(F->flags.closing)
continue;
/* 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->fd, 0, NULL, NULL);
hdl(F->fd, 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->fd, 0, NULL, NULL);
hdl(F->fd, data);
}
}
}
}
/*
* void comm_connect_tcp(int fd, const char *host, u_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(int fd, const char *host, u_short port,
struct sockaddr *clocal, int socklen, CNCB * callback,
void *data, int aftype, int timeout)
{
void *ipptr = NULL;
fde_t *F;
s_assert(fd >= 0);
F = comm_locate_fd(fd);
F->flags.called_connect = 1;
s_assert(callback);
F->connect.callback = callback;
F->connect.data = data;
memset(&F->connect.hostaddr, 0, sizeof(F->connect.hostaddr));
#ifdef IPV6
if(aftype == AF_INET6)
{
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&F->connect.hostaddr;
SET_SS_LEN(F->connect.hostaddr, sizeof(struct sockaddr_in6));
in6->sin6_port = htons(port);
in6->sin6_family = AF_INET6;
ipptr = &in6->sin6_addr;
} else
#endif
{
struct sockaddr_in *in = (struct sockaddr_in *)&F->connect.hostaddr;
SET_SS_LEN(F->connect.hostaddr, sizeof(struct sockaddr_in));
in->sin_port = htons(port);
in->sin_family = AF_INET;
ipptr = &in->sin_addr;
}
/* 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(F->fd, clocal, socklen) < 0))
{
/* Failure, call the callback with COMM_ERR_BIND */
comm_connect_callback(F->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().
*/
if(inetpton(aftype, host, ipptr) <= 0)
{
/* Send the DNS request, for the next level */
F->dns_query = MyMalloc(sizeof(struct DNSQuery));
F->dns_query->ptr = F;
F->dns_query->callback = comm_connect_dns_callback;
#ifdef IPV6
if (aftype == AF_INET6)
gethost_byname_type(host, F->dns_query, T_AAAA);
else
#endif
gethost_byname_type(host, F->dns_query, T_A);
}
else
{
/* We have a valid IP, so we just call tryconnect */
/* Make sure we actually set the timeout here .. */
comm_settimeout(F->fd, timeout * 1000, comm_connect_timeout, NULL);
comm_connect_tryconnect(F->fd, NULL);
}
}
/*
* comm_connect_callback() - call the callback, and continue with life
*/
static void
comm_connect_callback(int fd, int status)
{
CNCB *hdl;
fde_t *F = comm_locate_fd(fd);
/* This check is gross..but probably necessary */
if(F == NULL || F->connect.callback == NULL)
return;
/* Clear the connect flag + handler */
hdl = F->connect.callback;
F->connect.callback = NULL;
F->flags.called_connect = 0;
/* Clear the timeout handler */
comm_settimeout(F->fd, 0, NULL, NULL);
/* Call the handler */
hdl(F->fd, status, F->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(int 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, struct DNSReply *reply)
{
fde_t *F = vptr;
/* Free dns_query now to avoid double reslist free -- jilles */
MyFree(F->dns_query);
F->dns_query = NULL;
if(!reply)
{
comm_connect_callback(F->fd, COMM_ERR_DNS);
return;
}
/* No error, set a 10 second timeout */
comm_settimeout(F->fd, 30 * 1000, comm_connect_timeout, NULL);
/* Copy over the DNS reply info so we can use it in the connect() */
#ifdef IPV6
if(reply->addr.ss_family == AF_INET6)
{
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&F->connect.hostaddr;
memcpy(&in6->sin6_addr, &((struct sockaddr_in6 *)&reply->addr)->sin6_addr, sizeof(struct in6_addr));
}
else
#endif
{
struct sockaddr_in *in = (struct sockaddr_in *)&F->connect.hostaddr;
in->sin_addr.s_addr = ((struct sockaddr_in *)&reply->addr)->sin_addr.s_addr;
}
/* Now, call the tryconnect() routine to try a connect() */
comm_connect_tryconnect(F->fd, 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(int fd, void *notused)
{
int retval;
fde_t *F = comm_locate_fd(fd);
if(F->connect.callback == NULL)
return;
/* Try the connect() */
retval = connect(fd, (struct sockaddr *) &F->connect.hostaddr,
GET_SS_LEN(F->connect.hostaddr));
/* 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(F->fd, COMM_OK);
else if(ignoreErrno(errno))
/* Ignore error? Reschedule */
comm_setselect(F->fd, FDLIST_SERVER, COMM_SELECT_WRITE|COMM_SELECT_RETRY,
comm_connect_tryconnect, NULL, 0);
else
/* Error? Fail with COMM_ERR_CONNECT */
comm_connect_callback(F->fd, COMM_ERR_CONNECT);
return;
}
/* If we get here, we've suceeded, so call with COMM_OK */
comm_connect_callback(F->fd, COMM_OK);
}
/*
* comm_error_str() - 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_socket() - 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_socket(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 >= comm_max_connections)
{
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);
comm_fd_hack(&fd);
if(fd < 0)
return -1; /* errno will be passed through, yay.. */
#if defined(IPV6) && defined(IPV6_V6ONLY)
/*
* Make sure we can take both IPv4 and IPv6 connections
* on an AF_INET6 socket
*/
if(family == AF_INET6)
{
int off = 1;
if(setsockopt(fd, IPPROTO_IPV6, IPV6_V6ONLY, &off, sizeof(off)) == -1)
{
libcharybdis_log("comm_socket: Could not set IPV6_V6ONLY option to 1 on FD %d: %s",
fd, strerror(errno));
close(fd);
return -1;
}
}
#endif
/* Set the socket non-blocking, and other wonderful bits */
if(!comm_set_nb(fd))
{
libcharybdis_log("comm_open: Couldn't set FD %d non blocking: %s", fd, strerror(errno));
close(fd);
return -1;
}
/* Next, update things in our fd tracking */
comm_open(fd, FD_SOCKET, note);
return fd;
}
/*
* comm_accept() - accept an incoming connection
*
* This is a simple wrapper for accept() which enforces FD limits like
* comm_open() does.
*/
int
comm_accept(int fd, struct sockaddr *pn, socklen_t *addrlen)
{
int newfd;
if(number_fd >= comm_max_connections)
{
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(fd, (struct sockaddr *) pn, addrlen);
comm_fd_hack(&newfd);
if(newfd < 0)
return -1;
/* Set the socket non-blocking, and other wonderful bits */
if(!comm_set_nb(newfd))
{
libcharybdis_log("comm_accept: Couldn't set FD %d non blocking!", newfd);
close(newfd);
return -1;
}
/* Next, tag the FD as an incoming connection */
comm_open(newfd, FD_SOCKET, "Incoming connection");
/* .. and return */
return newfd;
}
/*
* If a sockaddr_storage is AF_INET6 but is a mapped IPv4
* socket manged the sockaddr.
*/
#ifndef mangle_mapped_sockaddr
void
mangle_mapped_sockaddr(struct sockaddr *in)
{
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)in;
if(in->sa_family == AF_INET)
return;
if(in->sa_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&in6->sin6_addr))
{
struct sockaddr_in in4;
memset(&in4, 0, sizeof(struct sockaddr_in));
in4.sin_family = AF_INET;
in4.sin_port = in6->sin6_port;
in4.sin_addr.s_addr = ((uint32_t *)&in6->sin6_addr)[3];
memcpy(in, &in4, sizeof(struct sockaddr_in));
}
return;
}
#endif
static void
fdlist_update_biggest(int fd, int opening)
{
if(fd < highest_fd)
return;
s_assert(fd < comm_max_connections);
if(fd > highest_fd)
{
/*
* s_assert that we are not closing a FD bigger than
* our known biggest FD
*/
s_assert(opening);
highest_fd = fd;
return;
}
/* if we are here, then fd == Biggest_FD */
/*
* s_assert that we are closing the biggest FD; we can't be
* re-opening it
*/
s_assert(!opening);
while (highest_fd >= 0 && comm_locate_fd(fd) != NULL)
highest_fd--;
}
void
fdlist_init(void)
{
static int initialized = 0;
struct rlimit limit;
if(!initialized)
{
memset(&fd_table, '\0', sizeof(dlink_list) * FD_HASH_SIZE);
/* set up comm_max_connections. */
if(!getrlimit(RLIMIT_NOFILE, &limit))
comm_max_connections = limit.rlim_cur;
initialized = 1;
}
}
/* Called to open a given filedescriptor */
void
comm_open(int fd, unsigned int type, const char *desc)
{
fde_t *F = comm_add_fd(fd);
s_assert(fd >= 0);
if(F->flags.open)
{
comm_close(fd);
}
s_assert(!F->flags.open);
F->fd = fd;
F->type = type;
F->flags.open = 1;
#ifdef NOTYET
F->defer.until = 0;
F->defer.n = 0;
F->defer.handler = NULL;
#endif
fdlist_update_biggest(fd, 1);
F->comm_index = -1;
F->list = FDLIST_NONE;
if(desc)
strlcpy(F->desc, desc, sizeof(F->desc));
number_fd++;
}
/* Called to close a given filedescriptor */
void
comm_close(int fd)
{
fde_t *F = comm_locate_fd(fd);
s_assert(F->flags.open);
/* All disk fd's MUST go through file_close() ! */
s_assert(F->type != FD_FILE);
if(F->type == FD_FILE)
{
s_assert(F->read_handler == NULL);
s_assert(F->write_handler == NULL);
}
comm_setselect(F->fd, FDLIST_NONE, COMM_SELECT_WRITE | COMM_SELECT_READ, NULL, NULL, 0);
comm_setflush(F->fd, 0, NULL, NULL);
F->timeout = 0;
if (F->dns_query != NULL)
{
delete_resolver_queries(F->dns_query);
MyFree(F->dns_query);
F->dns_query = NULL;
}
F->flags.open = 0;
fdlist_update_biggest(fd, 0);
number_fd--;
comm_remove_fd(fd);
/* Unlike squid, we're actually closing the FD here! -- adrian */
close(fd);
}
/*
* comm_dump() - dump the list of active filedescriptors
*/
void
comm_dump(struct Client *source_p)
{
int i;
for (i = 0; i <= FD_HASH_SIZE; i++)
{
dlink_node *n;
if (dlink_list_length(&fd_table[i]) <= 0)
continue;
DLINK_FOREACH(n, fd_table[i].head)
{
fde_t *F = (fde_t *) n->data;
if(F == NULL || !F->flags.open)
continue;
sendto_one_numeric(source_p, RPL_STATSDEBUG,
"F :fd %-3d bucket %-3d desc '%s'",
F->fd, i, F->desc);
}
}
}
/*
* comm_note() - set the fd note
*
* Note: must be careful not to overflow fd_table[fd].desc when
* calling.
*/
void
comm_note(int fd, const char *format, ...)
{
va_list args;
fde_t *F = comm_add_fd(fd); /* XXX: epoll, kqueue. */
if(format)
{
va_start(args, format);
ircvsnprintf(F->desc, FD_DESC_SZ, format, args);
va_end(args);
}
else
F->desc[0] = '\0';
}
extern int
comm_get_maxconnections(void)
{
fdlist_init();
return comm_max_connections;
}