2 * svc_unix.c, Server side for TCP/IP based RPC.
4 * Copyright (C) 2012-2024 Free Software Foundation, Inc.
5 * This file is part of the GNU C Library.
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21 * Copyright (c) 2010, Oracle America, Inc.
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38 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
39 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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45 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
46 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
47 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
48 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
50 * Actually implements two flavors of transporter -
51 * a unix rendezvouser (a listener and connection establisher)
52 * and a record/unix stream.
60 #include <sys/socket.h>
67 #include <shlib-compat.h>
70 * Ops vector for AF_UNIX based rpc service handle
72 static bool_t
svcunix_recv (SVCXPRT
*, struct rpc_msg
*);
73 static enum xprt_stat
svcunix_stat (SVCXPRT
*);
74 static bool_t
svcunix_getargs (SVCXPRT
*, xdrproc_t
, caddr_t
);
75 static bool_t
svcunix_reply (SVCXPRT
*, struct rpc_msg
*);
76 static bool_t
svcunix_freeargs (SVCXPRT
*, xdrproc_t
, caddr_t
);
77 static void svcunix_destroy (SVCXPRT
*);
79 static const struct xp_ops svcunix_op
=
90 * Ops vector for AF_UNIX rendezvous handler
92 static bool_t
rendezvous_request (SVCXPRT
*, struct rpc_msg
*);
93 static enum xprt_stat
rendezvous_stat (SVCXPRT
*);
94 static void svcunix_rendezvous_abort (void) __attribute__ ((__noreturn__
));
96 /* This function makes sure abort() relocation goes through PLT
97 and thus can be lazy bound. */
99 svcunix_rendezvous_abort (void)
104 static const struct xp_ops svcunix_rendezvous_op
=
108 (bool_t (*) (SVCXPRT
*, xdrproc_t
, caddr_t
)) svcunix_rendezvous_abort
,
109 (bool_t (*) (SVCXPRT
*, struct rpc_msg
*)) svcunix_rendezvous_abort
,
110 (bool_t (*) (SVCXPRT
*, xdrproc_t
, caddr_t
)) svcunix_rendezvous_abort
,
114 static int readunix (char*, char *, int);
115 static int writeunix (char *, char *, int);
116 static SVCXPRT
*makefd_xprt (int, u_int
, u_int
);
118 struct unix_rendezvous
{ /* kept in xprt->xp_p1 */
123 struct unix_conn
{ /* kept in xprt->xp_p1 */
124 enum xprt_stat strm_stat
;
127 char verf_body
[MAX_AUTH_BYTES
];
132 * xprt = svcunix_create(sock, send_buf_size, recv_buf_size);
134 * Creates, registers, and returns a (rpc) unix based transporter.
135 * Once *xprt is initialized, it is registered as a transporter
136 * see (svc.h, xprt_register). This routine returns
137 * a NULL if a problem occurred.
139 * If sock<0 then a socket is created, else sock is used.
140 * If the socket, sock is not bound to a port then svcunix_create
141 * binds it to an arbitrary port. The routine then starts a unix
142 * listener on the socket's associated port. In any (successful) case,
143 * xprt->xp_sock is the registered socket number and xprt->xp_port is the
144 * associated port number.
146 * Since unix streams do buffered io similar to stdio, the caller can specify
147 * how big the send and receive buffers are via the second and third parms;
148 * 0 => use the system default.
151 svcunix_create (int sock
, u_int sendsize
, u_int recvsize
, char *path
)
153 bool_t madesock
= FALSE
;
155 struct unix_rendezvous
*r
;
156 struct sockaddr_un addr
;
157 socklen_t len
= sizeof (addr
);
159 if (__sockaddr_un_set (&addr
, path
) < 0)
162 if (sock
== RPC_ANYSOCK
)
164 if ((sock
= __socket (AF_UNIX
, SOCK_STREAM
, 0)) < 0)
166 perror (_("svc_unix.c - AF_UNIX socket creation problem"));
167 return (SVCXPRT
*) NULL
;
171 __bind (sock
, (struct sockaddr
*) &addr
, len
);
173 if (__getsockname (sock
, (struct sockaddr
*) &addr
, &len
) != 0
174 || __listen (sock
, SOMAXCONN
) != 0)
176 perror (_("svc_unix.c - cannot getsockname or listen"));
179 return (SVCXPRT
*) NULL
;
182 r
= (struct unix_rendezvous
*) mem_alloc (sizeof (*r
));
183 xprt
= (SVCXPRT
*) mem_alloc (sizeof (SVCXPRT
));
184 if (r
== NULL
|| xprt
== NULL
)
186 __fxprintf (NULL
, "%s: %s", __func__
, _("out of memory\n"));
187 mem_free (r
, sizeof (*r
));
188 mem_free (xprt
, sizeof (SVCXPRT
));
191 r
->sendsize
= sendsize
;
192 r
->recvsize
= recvsize
;
194 xprt
->xp_p1
= (caddr_t
) r
;
195 xprt
->xp_verf
= _null_auth
;
196 xprt
->xp_ops
= &svcunix_rendezvous_op
;
198 xprt
->xp_sock
= sock
;
199 xprt_register (xprt
);
202 libc_hidden_nolink_sunrpc (svcunix_create
, GLIBC_2_1
)
205 * Like svunix_create(), except the routine takes any *open* UNIX file
206 * descriptor as its first input.
209 svcunixfd_create (int fd
, u_int sendsize
, u_int recvsize
)
211 return makefd_xprt (fd
, sendsize
, recvsize
);
213 libc_hidden_nolink_sunrpc (svcunixfd_create
, GLIBC_2_1
)
216 makefd_xprt (int fd
, u_int sendsize
, u_int recvsize
)
219 struct unix_conn
*cd
;
221 xprt
= (SVCXPRT
*) mem_alloc (sizeof (SVCXPRT
));
222 cd
= (struct unix_conn
*) mem_alloc (sizeof (struct unix_conn
));
223 if (xprt
== (SVCXPRT
*) NULL
|| cd
== (struct unix_conn
*) NULL
)
225 (void) __fxprintf (NULL
, "%s: %s", "svc_unix: makefd_xprt",
226 _("out of memory\n"));
227 mem_free (xprt
, sizeof (SVCXPRT
));
228 mem_free (cd
, sizeof (struct unix_conn
));
231 cd
->strm_stat
= XPRT_IDLE
;
232 xdrrec_create (&(cd
->xdrs
), sendsize
, recvsize
,
233 (caddr_t
) xprt
, readunix
, writeunix
);
235 xprt
->xp_p1
= (caddr_t
) cd
;
236 xprt
->xp_verf
.oa_base
= cd
->verf_body
;
237 xprt
->xp_addrlen
= 0;
238 xprt
->xp_ops
= &svcunix_op
; /* truly deals with calls */
239 xprt
->xp_port
= 0; /* this is a connection, not a rendezvouser */
241 xprt_register (xprt
);
246 rendezvous_request (SVCXPRT
*xprt
, struct rpc_msg
*errmsg
)
249 struct unix_rendezvous
*r
;
250 struct sockaddr_un addr
;
251 struct sockaddr_in in_addr
;
254 r
= (struct unix_rendezvous
*) xprt
->xp_p1
;
256 len
= sizeof (struct sockaddr_un
);
257 if ((sock
= accept (xprt
->xp_sock
, (struct sockaddr
*) &addr
, &len
)) < 0)
261 __svc_accept_failed ();
265 * make a new transporter (re-uses xprt)
267 memset (&in_addr
, '\0', sizeof (in_addr
));
268 in_addr
.sin_family
= AF_UNIX
;
269 xprt
= makefd_xprt (sock
, r
->sendsize
, r
->recvsize
);
271 /* If we are out of memory, makefd_xprt has already dumped an error. */
274 __svc_wait_on_error ();
278 memcpy (&xprt
->xp_raddr
, &in_addr
, sizeof (in_addr
));
279 xprt
->xp_addrlen
= len
;
280 return FALSE
; /* there is never an rpc msg to be processed */
283 static enum xprt_stat
284 rendezvous_stat (SVCXPRT
*xprt
)
290 svcunix_destroy (SVCXPRT
*xprt
)
292 struct unix_conn
*cd
= (struct unix_conn
*) xprt
->xp_p1
;
294 xprt_unregister (xprt
);
295 __close (xprt
->xp_sock
);
296 if (xprt
->xp_port
!= 0)
298 /* a rendezvouser socket */
303 /* an actual connection socket */
304 XDR_DESTROY (&(cd
->xdrs
));
306 mem_free ((caddr_t
) cd
, sizeof (struct unix_conn
));
307 mem_free ((caddr_t
) xprt
, sizeof (SVCXPRT
));
310 #ifdef SCM_CREDENTIALS
314 /* hack to make sure we have enough memory */
315 char dummy
[(CMSG_ALIGN (sizeof (struct ucred
)) - sizeof (struct ucred
) + sizeof (long))];
318 /* XXX This is not thread safe, but since the main functions in svc.c
319 and the rpcgen generated *_svc functions for the daemon are also not
320 thread safe and uses static global variables, it doesn't matter. */
321 static struct cmessage cm
;
325 __msgread (int sock
, void *data
, size_t cnt
)
338 #ifdef SCM_CREDENTIALS
339 msg
.msg_control
= (caddr_t
) &cm
;
340 msg
.msg_controllen
= sizeof (struct cmessage
);
347 if (__setsockopt (sock
, SOL_SOCKET
, SO_PASSCRED
, &on
, sizeof (on
)))
353 len
= __recvmsg (sock
, &msg
, 0);
356 if (msg
.msg_flags
& MSG_CTRUNC
|| len
== 0)
367 __msgwrite (int sock
, void *data
, size_t cnt
)
369 #ifndef SCM_CREDENTIALS
370 /* We cannot implement this reliably. */
371 __set_errno (ENOSYS
);
376 struct cmsghdr
*cmsg
= &cm
.cmsg
;
380 /* XXX I'm not sure, if gete?id() is always correct, or if we should use
381 get?id(). But since keyserv needs geteuid(), we have no other chance.
382 It would be much better, if the kernel could pass both to the server. */
383 cred
.pid
= __getpid ();
384 cred
.uid
= __geteuid ();
385 cred
.gid
= __getegid ();
387 memcpy (CMSG_DATA(cmsg
), &cred
, sizeof (struct ucred
));
388 cmsg
->cmsg_level
= SOL_SOCKET
;
389 cmsg
->cmsg_type
= SCM_CREDENTIALS
;
390 cmsg
->cmsg_len
= sizeof(*cmsg
) + sizeof(struct ucred
);
399 msg
.msg_control
= cmsg
;
400 msg
.msg_controllen
= CMSG_ALIGN(cmsg
->cmsg_len
);
404 len
= __sendmsg (sock
, &msg
, 0);
415 * reads data from the unix connection.
416 * any error is fatal and the connection is closed.
417 * (And a read of zero bytes is a half closed stream => error.)
420 readunix (char *xprtptr
, char *buf
, int len
)
422 SVCXPRT
*xprt
= (SVCXPRT
*) xprtptr
;
423 int sock
= xprt
->xp_sock
;
424 int milliseconds
= 35 * 1000;
425 struct pollfd pollfd
;
430 pollfd
.events
= POLLIN
;
431 switch (__poll (&pollfd
, 1, milliseconds
))
440 if ((pollfd
.revents
& POLLERR
) || (pollfd
.revents
& POLLHUP
)
441 || (pollfd
.revents
& POLLNVAL
))
446 while ((pollfd
.revents
& POLLIN
) == 0);
448 if ((len
= __msgread (sock
, buf
, len
)) > 0)
452 ((struct unix_conn
*) (xprt
->xp_p1
))->strm_stat
= XPRT_DIED
;
457 * writes data to the unix connection.
458 * Any error is fatal and the connection is closed.
461 writeunix (char *xprtptr
, char * buf
, int len
)
463 SVCXPRT
*xprt
= (SVCXPRT
*) xprtptr
;
466 for (cnt
= len
; cnt
> 0; cnt
-= i
, buf
+= i
)
468 if ((i
= __msgwrite (xprt
->xp_sock
, buf
, cnt
)) < 0)
470 ((struct unix_conn
*) (xprt
->xp_p1
))->strm_stat
= XPRT_DIED
;
477 static enum xprt_stat
478 svcunix_stat (SVCXPRT
*xprt
)
480 struct unix_conn
*cd
=
481 (struct unix_conn
*) (xprt
->xp_p1
);
483 if (cd
->strm_stat
== XPRT_DIED
)
485 if (!xdrrec_eof (&(cd
->xdrs
)))
486 return XPRT_MOREREQS
;
491 svcunix_recv (SVCXPRT
*xprt
, struct rpc_msg
*msg
)
493 struct unix_conn
*cd
= (struct unix_conn
*) (xprt
->xp_p1
);
494 XDR
*xdrs
= &(cd
->xdrs
);
496 xdrs
->x_op
= XDR_DECODE
;
497 xdrrec_skiprecord (xdrs
);
498 if (xdr_callmsg (xdrs
, msg
))
500 cd
->x_id
= msg
->rm_xid
;
501 /* set up verifiers */
502 #ifdef SCM_CREDENTIALS
503 msg
->rm_call
.cb_verf
.oa_flavor
= AUTH_UNIX
;
504 msg
->rm_call
.cb_verf
.oa_base
= (caddr_t
) &cm
;
505 msg
->rm_call
.cb_verf
.oa_length
= sizeof (cm
);
509 cd
->strm_stat
= XPRT_DIED
; /* XXXX */
514 svcunix_getargs (SVCXPRT
*xprt
, xdrproc_t xdr_args
, caddr_t args_ptr
)
516 return (*xdr_args
) (&(((struct unix_conn
*) (xprt
->xp_p1
))->xdrs
),
521 svcunix_freeargs (SVCXPRT
*xprt
, xdrproc_t xdr_args
, caddr_t args_ptr
)
523 XDR
*xdrs
= &(((struct unix_conn
*) (xprt
->xp_p1
))->xdrs
);
525 xdrs
->x_op
= XDR_FREE
;
526 return (*xdr_args
) (xdrs
, args_ptr
);
530 svcunix_reply (SVCXPRT
*xprt
, struct rpc_msg
*msg
)
532 struct unix_conn
*cd
= (struct unix_conn
*) (xprt
->xp_p1
);
533 XDR
*xdrs
= &(cd
->xdrs
);
536 xdrs
->x_op
= XDR_ENCODE
;
537 msg
->rm_xid
= cd
->x_id
;
538 stat
= xdr_replymsg (xdrs
, msg
);
539 (void) xdrrec_endofrecord (xdrs
, TRUE
);