glibc/sunrpc/svc_tcp.c

437 lines
12 KiB
C

/*
* svc_tcp.c, Server side for TCP/IP based RPC.
*
* Copyright (C) 2012-2023 Free Software Foundation, Inc.
* This file is part of the GNU C Library.
*
* The GNU C Library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* The GNU C Library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with the GNU C Library; if not, see
* <https://www.gnu.org/licenses/>.
*
* Copyright (c) 2010, Oracle America, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of the "Oracle America, Inc." nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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
* COPYRIGHT HOLDER OR CONTRIBUTORS 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.
*
* Actually implements two flavors of transporter -
* a tcp rendezvouser (a listener and connection establisher)
* and a record/tcp stream.
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <libintl.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <sys/poll.h>
#include <errno.h>
#include <stdlib.h>
#include <wchar.h>
#include <libio/iolibio.h>
#include <shlib-compat.h>
/*
* Ops vector for TCP/IP based rpc service handle
*/
static bool_t svctcp_recv (SVCXPRT *, struct rpc_msg *);
static enum xprt_stat svctcp_stat (SVCXPRT *);
static bool_t svctcp_getargs (SVCXPRT *, xdrproc_t, caddr_t);
static bool_t svctcp_reply (SVCXPRT *, struct rpc_msg *);
static bool_t svctcp_freeargs (SVCXPRT *, xdrproc_t, caddr_t);
static void svctcp_destroy (SVCXPRT *);
static const struct xp_ops svctcp_op =
{
svctcp_recv,
svctcp_stat,
svctcp_getargs,
svctcp_reply,
svctcp_freeargs,
svctcp_destroy
};
/*
* Ops vector for TCP/IP rendezvous handler
*/
static bool_t rendezvous_request (SVCXPRT *, struct rpc_msg *);
static enum xprt_stat rendezvous_stat (SVCXPRT *);
static void svctcp_rendezvous_abort (void) __attribute__ ((__noreturn__));
/* This function makes sure abort() relocation goes through PLT
and thus can be lazy bound. */
static void
svctcp_rendezvous_abort (void)
{
abort ();
};
static const struct xp_ops svctcp_rendezvous_op =
{
rendezvous_request,
rendezvous_stat,
(bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) svctcp_rendezvous_abort,
(bool_t (*) (SVCXPRT *, struct rpc_msg *)) svctcp_rendezvous_abort,
(bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) svctcp_rendezvous_abort,
svctcp_destroy
};
static int readtcp (char*, char *, int);
static int writetcp (char *, char *, int);
static SVCXPRT *makefd_xprt (int, u_int, u_int);
struct tcp_rendezvous
{ /* kept in xprt->xp_p1 */
u_int sendsize;
u_int recvsize;
};
struct tcp_conn
{ /* kept in xprt->xp_p1 */
enum xprt_stat strm_stat;
u_long x_id;
XDR xdrs;
char verf_body[MAX_AUTH_BYTES];
};
/*
* Usage:
* xprt = svctcp_create(sock, send_buf_size, recv_buf_size);
*
* Creates, registers, and returns a (rpc) tcp based transporter.
* Once *xprt is initialized, it is registered as a transporter
* see (svc.h, xprt_register). This routine returns
* a NULL if a problem occurred.
*
* If sock<0 then a socket is created, else sock is used.
* If the socket, sock is not bound to a port then svctcp_create
* binds it to an arbitrary port. The routine then starts a tcp
* listener on the socket's associated port. In any (successful) case,
* xprt->xp_sock is the registered socket number and xprt->xp_port is the
* associated port number.
*
* Since tcp streams do buffered io similar to stdio, the caller can specify
* how big the send and receive buffers are via the second and third parms;
* 0 => use the system default.
*/
SVCXPRT *
svctcp_create (int sock, u_int sendsize, u_int recvsize)
{
bool_t madesock = FALSE;
SVCXPRT *xprt;
struct tcp_rendezvous *r;
struct sockaddr_in addr;
socklen_t len = sizeof (struct sockaddr_in);
if (sock == RPC_ANYSOCK)
{
if ((sock = __socket (AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
{
perror (_("svc_tcp.c - tcp socket creation problem"));
return (SVCXPRT *) NULL;
}
madesock = TRUE;
}
memset ((char *) &addr, 0, sizeof (addr));
addr.sin_family = AF_INET;
if (bindresvport (sock, &addr))
{
addr.sin_port = 0;
(void) __bind (sock, (struct sockaddr *) &addr, len);
}
if ((__getsockname (sock, (struct sockaddr *) &addr, &len) != 0) ||
(__listen (sock, SOMAXCONN) != 0))
{
perror (_("svc_tcp.c - cannot getsockname or listen"));
if (madesock)
(void) __close (sock);
return (SVCXPRT *) NULL;
}
r = (struct tcp_rendezvous *) mem_alloc (sizeof (*r));
xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
if (r == NULL || xprt == NULL)
{
(void) __fxprintf (NULL, "%s: %s", __func__, _("out of memory\n"));
mem_free (r, sizeof (*r));
mem_free (xprt, sizeof (SVCXPRT));
return NULL;
}
r->sendsize = sendsize;
r->recvsize = recvsize;
xprt->xp_p2 = NULL;
xprt->xp_p1 = (caddr_t) r;
xprt->xp_verf = _null_auth;
xprt->xp_ops = &svctcp_rendezvous_op;
xprt->xp_port = ntohs (addr.sin_port);
xprt->xp_sock = sock;
xprt_register (xprt);
return xprt;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (svctcp_create)
#else
libc_hidden_nolink_sunrpc (svctcp_create, GLIBC_2_0)
#endif
/*
* Like svtcp_create(), except the routine takes any *open* UNIX file
* descriptor as its first input.
*/
SVCXPRT *
svcfd_create (int fd, u_int sendsize, u_int recvsize)
{
return makefd_xprt (fd, sendsize, recvsize);
}
libc_hidden_nolink_sunrpc (svcfd_create, GLIBC_2_0)
static SVCXPRT *
makefd_xprt (int fd, u_int sendsize, u_int recvsize)
{
SVCXPRT *xprt;
struct tcp_conn *cd;
xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
cd = (struct tcp_conn *) mem_alloc (sizeof (struct tcp_conn));
if (xprt == (SVCXPRT *) NULL || cd == NULL)
{
(void) __fxprintf (NULL, "%s: %s", "svc_tcp: makefd_xprt",
_("out of memory\n"));
mem_free (xprt, sizeof (SVCXPRT));
mem_free (cd, sizeof (struct tcp_conn));
return NULL;
}
cd->strm_stat = XPRT_IDLE;
xdrrec_create (&(cd->xdrs), sendsize, recvsize,
(caddr_t) xprt, readtcp, writetcp);
xprt->xp_p2 = NULL;
xprt->xp_p1 = (caddr_t) cd;
xprt->xp_verf.oa_base = cd->verf_body;
xprt->xp_addrlen = 0;
xprt->xp_ops = &svctcp_op; /* truly deals with calls */
xprt->xp_port = 0; /* this is a connection, not a rendezvouser */
xprt->xp_sock = fd;
xprt_register (xprt);
return xprt;
}
static bool_t
rendezvous_request (SVCXPRT *xprt, struct rpc_msg *errmsg)
{
int sock;
struct tcp_rendezvous *r;
struct sockaddr_in addr;
socklen_t len;
r = (struct tcp_rendezvous *) xprt->xp_p1;
again:
len = sizeof (struct sockaddr_in);
if ((sock = accept (xprt->xp_sock, (struct sockaddr *) &addr, &len)) < 0)
{
if (errno == EINTR)
goto again;
__svc_accept_failed ();
return FALSE;
}
/*
* make a new transporter (re-uses xprt)
*/
xprt = makefd_xprt (sock, r->sendsize, r->recvsize);
/* If we are out of memory, makefd_xprt has already dumped an error. */
if (xprt == NULL)
{
__svc_wait_on_error ();
return FALSE;
}
memcpy (&xprt->xp_raddr, &addr, sizeof (addr));
xprt->xp_addrlen = len;
return FALSE; /* there is never an rpc msg to be processed */
}
static enum xprt_stat
rendezvous_stat (SVCXPRT *xprt)
{
return XPRT_IDLE;
}
static void
svctcp_destroy (SVCXPRT *xprt)
{
struct tcp_conn *cd = (struct tcp_conn *) xprt->xp_p1;
xprt_unregister (xprt);
(void) __close (xprt->xp_sock);
if (xprt->xp_port != 0)
{
/* a rendezvouser socket */
xprt->xp_port = 0;
}
else
{
/* an actual connection socket */
XDR_DESTROY (&(cd->xdrs));
}
mem_free ((caddr_t) cd, sizeof (struct tcp_conn));
mem_free ((caddr_t) xprt, sizeof (SVCXPRT));
}
/*
* reads data from the tcp connection.
* any error is fatal and the connection is closed.
* (And a read of zero bytes is a half closed stream => error.)
*/
static int
readtcp (char *xprtptr, char *buf, int len)
{
SVCXPRT *xprt = (SVCXPRT *)xprtptr;
int sock = xprt->xp_sock;
int milliseconds = 35 * 1000;
struct pollfd pollfd;
do
{
pollfd.fd = sock;
pollfd.events = POLLIN;
switch (__poll (&pollfd, 1, milliseconds))
{
case -1:
if (errno == EINTR)
continue;
/*FALLTHROUGH*/
case 0:
goto fatal_err;
default:
if ((pollfd.revents & POLLERR) || (pollfd.revents & POLLHUP)
|| (pollfd.revents & POLLNVAL))
goto fatal_err;
break;
}
}
while ((pollfd.revents & POLLIN) == 0);
if ((len = __read (sock, buf, len)) > 0)
return len;
fatal_err:
((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
return -1;
}
/*
* writes data to the tcp connection.
* Any error is fatal and the connection is closed.
*/
static int
writetcp (char *xprtptr, char * buf, int len)
{
SVCXPRT *xprt = (SVCXPRT *)xprtptr;
int i, cnt;
for (cnt = len; cnt > 0; cnt -= i, buf += i)
{
if ((i = __write (xprt->xp_sock, buf, cnt)) < 0)
{
((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED;
return -1;
}
}
return len;
}
static enum xprt_stat
svctcp_stat (SVCXPRT *xprt)
{
struct tcp_conn *cd =
(struct tcp_conn *) (xprt->xp_p1);
if (cd->strm_stat == XPRT_DIED)
return XPRT_DIED;
if (!xdrrec_eof (&(cd->xdrs)))
return XPRT_MOREREQS;
return XPRT_IDLE;
}
static bool_t
svctcp_recv (SVCXPRT *xprt, struct rpc_msg *msg)
{
struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1);
XDR *xdrs = &(cd->xdrs);
xdrs->x_op = XDR_DECODE;
(void) xdrrec_skiprecord (xdrs);
if (xdr_callmsg (xdrs, msg))
{
cd->x_id = msg->rm_xid;
return TRUE;
}
cd->strm_stat = XPRT_DIED; /* XXXX */
return FALSE;
}
static bool_t
svctcp_getargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
{
return ((*xdr_args) (&(((struct tcp_conn *)
(xprt->xp_p1))->xdrs), args_ptr));
}
static bool_t
svctcp_freeargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
{
XDR *xdrs = &(((struct tcp_conn *) (xprt->xp_p1))->xdrs);
xdrs->x_op = XDR_FREE;
return ((*xdr_args) (xdrs, args_ptr));
}
static bool_t
svctcp_reply (SVCXPRT *xprt, struct rpc_msg *msg)
{
struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1);
XDR *xdrs = &(cd->xdrs);
bool_t stat;
xdrs->x_op = XDR_ENCODE;
msg->rm_xid = cd->x_id;
stat = xdr_replymsg (xdrs, msg);
(void) xdrrec_endofrecord (xdrs, TRUE);
return stat;
}