1 | /* |
2 | * svc_tcp.c, Server side for TCP/IP based RPC. |
3 | * |
4 | * Copyright (C) 2012-2017 Free Software Foundation, Inc. |
5 | * This file is part of the GNU C Library. |
6 | * |
7 | * The GNU C Library is free software; you can redistribute it and/or |
8 | * modify it under the terms of the GNU Lesser General Public |
9 | * License as published by the Free Software Foundation; either |
10 | * version 2.1 of the License, or (at your option) any later version. |
11 | * |
12 | * The GNU C Library is distributed in the hope that it will be useful, |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
15 | * Lesser General Public License for more details. |
16 | * |
17 | * You should have received a copy of the GNU Lesser General Public |
18 | * License along with the GNU C Library; if not, see |
19 | * <http://www.gnu.org/licenses/>. |
20 | * |
21 | * Copyright (c) 2010, Oracle America, Inc. |
22 | * |
23 | * Redistribution and use in source and binary forms, with or without |
24 | * modification, are permitted provided that the following conditions are |
25 | * met: |
26 | * |
27 | * * Redistributions of source code must retain the above copyright |
28 | * notice, this list of conditions and the following disclaimer. |
29 | * * Redistributions in binary form must reproduce the above |
30 | * copyright notice, this list of conditions and the following |
31 | * disclaimer in the documentation and/or other materials |
32 | * provided with the distribution. |
33 | * * Neither the name of the "Oracle America, Inc." nor the names of its |
34 | * contributors may be used to endorse or promote products derived |
35 | * from this software without specific prior written permission. |
36 | * |
37 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
38 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
39 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
40 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
41 | * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, |
42 | * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
43 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE |
44 | * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
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. |
49 | * |
50 | * Actually implements two flavors of transporter - |
51 | * a tcp rendezvouser (a listener and connection establisher) |
52 | * and a record/tcp stream. |
53 | */ |
54 | |
55 | #include <stdio.h> |
56 | #include <unistd.h> |
57 | #include <string.h> |
58 | #include <libintl.h> |
59 | #include <rpc/rpc.h> |
60 | #include <sys/socket.h> |
61 | #include <sys/poll.h> |
62 | #include <errno.h> |
63 | #include <stdlib.h> |
64 | |
65 | #include <wchar.h> |
66 | #include <libio/iolibio.h> |
67 | #include <shlib-compat.h> |
68 | |
69 | /* |
70 | * Ops vector for TCP/IP based rpc service handle |
71 | */ |
72 | static bool_t svctcp_recv (SVCXPRT *, struct rpc_msg *); |
73 | static enum xprt_stat svctcp_stat (SVCXPRT *); |
74 | static bool_t svctcp_getargs (SVCXPRT *, xdrproc_t, caddr_t); |
75 | static bool_t svctcp_reply (SVCXPRT *, struct rpc_msg *); |
76 | static bool_t svctcp_freeargs (SVCXPRT *, xdrproc_t, caddr_t); |
77 | static void svctcp_destroy (SVCXPRT *); |
78 | |
79 | static const struct xp_ops svctcp_op = |
80 | { |
81 | svctcp_recv, |
82 | svctcp_stat, |
83 | svctcp_getargs, |
84 | svctcp_reply, |
85 | svctcp_freeargs, |
86 | svctcp_destroy |
87 | }; |
88 | |
89 | /* |
90 | * Ops vector for TCP/IP rendezvous handler |
91 | */ |
92 | static bool_t rendezvous_request (SVCXPRT *, struct rpc_msg *); |
93 | static enum xprt_stat rendezvous_stat (SVCXPRT *); |
94 | static void svctcp_rendezvous_abort (void) __attribute__ ((__noreturn__)); |
95 | |
96 | /* This function makes sure abort() relocation goes through PLT |
97 | and thus can be lazy bound. */ |
98 | static void |
99 | svctcp_rendezvous_abort (void) |
100 | { |
101 | abort (); |
102 | }; |
103 | |
104 | static const struct xp_ops svctcp_rendezvous_op = |
105 | { |
106 | rendezvous_request, |
107 | rendezvous_stat, |
108 | (bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) svctcp_rendezvous_abort, |
109 | (bool_t (*) (SVCXPRT *, struct rpc_msg *)) svctcp_rendezvous_abort, |
110 | (bool_t (*) (SVCXPRT *, xdrproc_t, caddr_t)) svctcp_rendezvous_abort, |
111 | svctcp_destroy |
112 | }; |
113 | |
114 | static int readtcp (char*, char *, int); |
115 | static int writetcp (char *, char *, int); |
116 | static SVCXPRT *makefd_xprt (int, u_int, u_int) internal_function; |
117 | |
118 | struct tcp_rendezvous |
119 | { /* kept in xprt->xp_p1 */ |
120 | u_int sendsize; |
121 | u_int recvsize; |
122 | }; |
123 | |
124 | struct tcp_conn |
125 | { /* kept in xprt->xp_p1 */ |
126 | enum xprt_stat strm_stat; |
127 | u_long x_id; |
128 | XDR xdrs; |
129 | char verf_body[MAX_AUTH_BYTES]; |
130 | }; |
131 | |
132 | /* |
133 | * Usage: |
134 | * xprt = svctcp_create(sock, send_buf_size, recv_buf_size); |
135 | * |
136 | * Creates, registers, and returns a (rpc) tcp based transporter. |
137 | * Once *xprt is initialized, it is registered as a transporter |
138 | * see (svc.h, xprt_register). This routine returns |
139 | * a NULL if a problem occurred. |
140 | * |
141 | * If sock<0 then a socket is created, else sock is used. |
142 | * If the socket, sock is not bound to a port then svctcp_create |
143 | * binds it to an arbitrary port. The routine then starts a tcp |
144 | * listener on the socket's associated port. In any (successful) case, |
145 | * xprt->xp_sock is the registered socket number and xprt->xp_port is the |
146 | * associated port number. |
147 | * |
148 | * Since tcp streams do buffered io similar to stdio, the caller can specify |
149 | * how big the send and receive buffers are via the second and third parms; |
150 | * 0 => use the system default. |
151 | */ |
152 | SVCXPRT * |
153 | svctcp_create (int sock, u_int sendsize, u_int recvsize) |
154 | { |
155 | bool_t madesock = FALSE; |
156 | SVCXPRT *xprt; |
157 | struct tcp_rendezvous *r; |
158 | struct sockaddr_in addr; |
159 | socklen_t len = sizeof (struct sockaddr_in); |
160 | |
161 | if (sock == RPC_ANYSOCK) |
162 | { |
163 | if ((sock = __socket (AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) |
164 | { |
165 | perror (_("svc_tcp.c - tcp socket creation problem" )); |
166 | return (SVCXPRT *) NULL; |
167 | } |
168 | madesock = TRUE; |
169 | } |
170 | memset ((char *) &addr, 0, sizeof (addr)); |
171 | addr.sin_family = AF_INET; |
172 | if (bindresvport (sock, &addr)) |
173 | { |
174 | addr.sin_port = 0; |
175 | (void) __bind (sock, (struct sockaddr *) &addr, len); |
176 | } |
177 | if ((__getsockname (sock, (struct sockaddr *) &addr, &len) != 0) || |
178 | (__listen (sock, SOMAXCONN) != 0)) |
179 | { |
180 | perror (_("svc_tcp.c - cannot getsockname or listen" )); |
181 | if (madesock) |
182 | (void) __close (sock); |
183 | return (SVCXPRT *) NULL; |
184 | } |
185 | r = (struct tcp_rendezvous *) mem_alloc (sizeof (*r)); |
186 | xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT)); |
187 | if (r == NULL || xprt == NULL) |
188 | { |
189 | (void) __fxprintf (NULL, "%s: %s" , __func__, _("out of memory\n" )); |
190 | mem_free (r, sizeof (*r)); |
191 | mem_free (xprt, sizeof (SVCXPRT)); |
192 | return NULL; |
193 | } |
194 | r->sendsize = sendsize; |
195 | r->recvsize = recvsize; |
196 | xprt->xp_p2 = NULL; |
197 | xprt->xp_p1 = (caddr_t) r; |
198 | xprt->xp_verf = _null_auth; |
199 | xprt->xp_ops = &svctcp_rendezvous_op; |
200 | xprt->xp_port = ntohs (addr.sin_port); |
201 | xprt->xp_sock = sock; |
202 | xprt_register (xprt); |
203 | return xprt; |
204 | } |
205 | #ifdef EXPORT_RPC_SYMBOLS |
206 | libc_hidden_def (svctcp_create) |
207 | #else |
208 | libc_hidden_nolink_sunrpc (svctcp_create, GLIBC_2_0) |
209 | #endif |
210 | |
211 | /* |
212 | * Like svtcp_create(), except the routine takes any *open* UNIX file |
213 | * descriptor as its first input. |
214 | */ |
215 | SVCXPRT * |
216 | svcfd_create (int fd, u_int sendsize, u_int recvsize) |
217 | { |
218 | return makefd_xprt (fd, sendsize, recvsize); |
219 | } |
220 | libc_hidden_nolink_sunrpc (svcfd_create, GLIBC_2_0) |
221 | |
222 | static SVCXPRT * |
223 | internal_function |
224 | makefd_xprt (int fd, u_int sendsize, u_int recvsize) |
225 | { |
226 | SVCXPRT *xprt; |
227 | struct tcp_conn *cd; |
228 | |
229 | xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT)); |
230 | cd = (struct tcp_conn *) mem_alloc (sizeof (struct tcp_conn)); |
231 | if (xprt == (SVCXPRT *) NULL || cd == NULL) |
232 | { |
233 | (void) __fxprintf (NULL, "%s: %s" , "svc_tcp: makefd_xprt" , |
234 | _("out of memory\n" )); |
235 | mem_free (xprt, sizeof (SVCXPRT)); |
236 | mem_free (cd, sizeof (struct tcp_conn)); |
237 | return NULL; |
238 | } |
239 | cd->strm_stat = XPRT_IDLE; |
240 | xdrrec_create (&(cd->xdrs), sendsize, recvsize, |
241 | (caddr_t) xprt, readtcp, writetcp); |
242 | xprt->xp_p2 = NULL; |
243 | xprt->xp_p1 = (caddr_t) cd; |
244 | xprt->xp_verf.oa_base = cd->verf_body; |
245 | xprt->xp_addrlen = 0; |
246 | xprt->xp_ops = &svctcp_op; /* truly deals with calls */ |
247 | xprt->xp_port = 0; /* this is a connection, not a rendezvouser */ |
248 | xprt->xp_sock = fd; |
249 | xprt_register (xprt); |
250 | return xprt; |
251 | } |
252 | |
253 | static bool_t |
254 | rendezvous_request (SVCXPRT *xprt, struct rpc_msg *errmsg) |
255 | { |
256 | int sock; |
257 | struct tcp_rendezvous *r; |
258 | struct sockaddr_in addr; |
259 | socklen_t len; |
260 | |
261 | r = (struct tcp_rendezvous *) xprt->xp_p1; |
262 | again: |
263 | len = sizeof (struct sockaddr_in); |
264 | if ((sock = accept (xprt->xp_sock, (struct sockaddr *) &addr, &len)) < 0) |
265 | { |
266 | if (errno == EINTR) |
267 | goto again; |
268 | __svc_accept_failed (); |
269 | return FALSE; |
270 | } |
271 | /* |
272 | * make a new transporter (re-uses xprt) |
273 | */ |
274 | xprt = makefd_xprt (sock, r->sendsize, r->recvsize); |
275 | memcpy (&xprt->xp_raddr, &addr, sizeof (addr)); |
276 | xprt->xp_addrlen = len; |
277 | return FALSE; /* there is never an rpc msg to be processed */ |
278 | } |
279 | |
280 | static enum xprt_stat |
281 | rendezvous_stat (SVCXPRT *xprt) |
282 | { |
283 | return XPRT_IDLE; |
284 | } |
285 | |
286 | static void |
287 | svctcp_destroy (SVCXPRT *xprt) |
288 | { |
289 | struct tcp_conn *cd = (struct tcp_conn *) xprt->xp_p1; |
290 | |
291 | xprt_unregister (xprt); |
292 | (void) __close (xprt->xp_sock); |
293 | if (xprt->xp_port != 0) |
294 | { |
295 | /* a rendezvouser socket */ |
296 | xprt->xp_port = 0; |
297 | } |
298 | else |
299 | { |
300 | /* an actual connection socket */ |
301 | XDR_DESTROY (&(cd->xdrs)); |
302 | } |
303 | mem_free ((caddr_t) cd, sizeof (struct tcp_conn)); |
304 | mem_free ((caddr_t) xprt, sizeof (SVCXPRT)); |
305 | } |
306 | |
307 | |
308 | /* |
309 | * reads data from the tcp connection. |
310 | * any error is fatal and the connection is closed. |
311 | * (And a read of zero bytes is a half closed stream => error.) |
312 | */ |
313 | static int |
314 | readtcp (char *xprtptr, char *buf, int len) |
315 | { |
316 | SVCXPRT *xprt = (SVCXPRT *)xprtptr; |
317 | int sock = xprt->xp_sock; |
318 | int milliseconds = 35 * 1000; |
319 | struct pollfd pollfd; |
320 | |
321 | do |
322 | { |
323 | pollfd.fd = sock; |
324 | pollfd.events = POLLIN; |
325 | switch (__poll (&pollfd, 1, milliseconds)) |
326 | { |
327 | case -1: |
328 | if (errno == EINTR) |
329 | continue; |
330 | /*FALLTHROUGH*/ |
331 | case 0: |
332 | goto fatal_err; |
333 | default: |
334 | if ((pollfd.revents & POLLERR) || (pollfd.revents & POLLHUP) |
335 | || (pollfd.revents & POLLNVAL)) |
336 | goto fatal_err; |
337 | break; |
338 | } |
339 | } |
340 | while ((pollfd.revents & POLLIN) == 0); |
341 | |
342 | if ((len = __read (sock, buf, len)) > 0) |
343 | return len; |
344 | |
345 | fatal_err: |
346 | ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED; |
347 | return -1; |
348 | } |
349 | |
350 | /* |
351 | * writes data to the tcp connection. |
352 | * Any error is fatal and the connection is closed. |
353 | */ |
354 | static int |
355 | writetcp (char *xprtptr, char * buf, int len) |
356 | { |
357 | SVCXPRT *xprt = (SVCXPRT *)xprtptr; |
358 | int i, cnt; |
359 | |
360 | for (cnt = len; cnt > 0; cnt -= i, buf += i) |
361 | { |
362 | if ((i = __write (xprt->xp_sock, buf, cnt)) < 0) |
363 | { |
364 | ((struct tcp_conn *) (xprt->xp_p1))->strm_stat = XPRT_DIED; |
365 | return -1; |
366 | } |
367 | } |
368 | return len; |
369 | } |
370 | |
371 | static enum xprt_stat |
372 | svctcp_stat (SVCXPRT *xprt) |
373 | { |
374 | struct tcp_conn *cd = |
375 | (struct tcp_conn *) (xprt->xp_p1); |
376 | |
377 | if (cd->strm_stat == XPRT_DIED) |
378 | return XPRT_DIED; |
379 | if (!xdrrec_eof (&(cd->xdrs))) |
380 | return XPRT_MOREREQS; |
381 | return XPRT_IDLE; |
382 | } |
383 | |
384 | static bool_t |
385 | svctcp_recv (SVCXPRT *xprt, struct rpc_msg *msg) |
386 | { |
387 | struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1); |
388 | XDR *xdrs = &(cd->xdrs); |
389 | |
390 | xdrs->x_op = XDR_DECODE; |
391 | (void) xdrrec_skiprecord (xdrs); |
392 | if (xdr_callmsg (xdrs, msg)) |
393 | { |
394 | cd->x_id = msg->rm_xid; |
395 | return TRUE; |
396 | } |
397 | cd->strm_stat = XPRT_DIED; /* XXXX */ |
398 | return FALSE; |
399 | } |
400 | |
401 | static bool_t |
402 | svctcp_getargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr) |
403 | { |
404 | return ((*xdr_args) (&(((struct tcp_conn *) |
405 | (xprt->xp_p1))->xdrs), args_ptr)); |
406 | } |
407 | |
408 | static bool_t |
409 | svctcp_freeargs (SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr) |
410 | { |
411 | XDR *xdrs = &(((struct tcp_conn *) (xprt->xp_p1))->xdrs); |
412 | |
413 | xdrs->x_op = XDR_FREE; |
414 | return ((*xdr_args) (xdrs, args_ptr)); |
415 | } |
416 | |
417 | static bool_t |
418 | svctcp_reply (SVCXPRT *xprt, struct rpc_msg *msg) |
419 | { |
420 | struct tcp_conn *cd = (struct tcp_conn *) (xprt->xp_p1); |
421 | XDR *xdrs = &(cd->xdrs); |
422 | bool_t stat; |
423 | |
424 | xdrs->x_op = XDR_ENCODE; |
425 | msg->rm_xid = cd->x_id; |
426 | stat = xdr_replymsg (xdrs, msg); |
427 | (void) xdrrec_endofrecord (xdrs, TRUE); |
428 | return stat; |
429 | } |
430 | |