1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 /*
43  * svc_tcp.c, Server side for TCP/IP based RPC.
44  *
45  * Actually implements two flavors of transporter -
46  * a tcp rendezvouser (a listner and connection establisher)
47  * and a record/tcp stream.
48  */
49 
50 #include <rpc/rpc.h>
51 #include <sys/socket.h>
52 #include <sys/time.h>
53 #include <errno.h>
54 #include <syslog.h>
55 #include <malloc.h>
56 #include <stdio.h>
57 
58 extern bool_t abort();
59 extern int errno;
60 extern SVCXPRT *svc_xprt_alloc();
61 extern void svc_xprt_free();
62 extern int _socket(int, int, int);
63 extern int _bind(int, const struct sockaddr *, int);
64 extern int _getsockname(int, struct sockaddr *, int *);
65 extern int _listen(int, int);
66 extern int _accept(int, struct sockaddr *, int *);
67 extern int bindresvport(int, struct sockaddr_in *);
68 
69 static struct xp_ops *svctcp_ops();
70 static struct xp_ops *svctcp_rendezvous_ops();
71 
72 static int readtcp(), writetcp();
73 static SVCXPRT *makefd_xprt();
74 
75 struct tcp_rendezvous { /* kept in xprt->xp_p1 */
76 	u_int sendsize;
77 	u_int recvsize;
78 };
79 
80 struct tcp_conn {  /* kept in xprt->xp_p1 */
81 	enum xprt_stat strm_stat;
82 	uint32_t x_id;
83 	XDR xdrs;
84 	char verf_body[MAX_AUTH_BYTES];
85 };
86 
87 /*
88  * Usage:
89  *	xprt = svctcp_create(sock, send_buf_size, recv_buf_size);
90  *
91  * Creates, registers, and returns a (rpc) tcp based transporter.
92  * Once *xprt is initialized, it is registered as a transporter
93  * see (svc.h, xprt_register).  This routine returns
94  * a NULL if a problem occurred.
95  *
96  * If sock<0 then a socket is created, else sock is used.
97  * If the socket, sock is not bound to a port then svctcp_create
98  * binds it to an arbitrary port.  The routine then starts a tcp
99  * listener on the socket's associated port.  In any (successful) case,
100  * xprt->xp_sock is the registered socket number and xprt->xp_port is the
101  * associated port number.
102  *
103  * Since tcp streams do buffered io similar to stdio, the caller can specify
104  * how big the send and receive buffers are via the second and third parms;
105  * 0 => use the system default.
106  */
107 SVCXPRT *
svctcp_create(sock,sendsize,recvsize)108 svctcp_create(sock, sendsize, recvsize)
109 	register int sock;
110 	u_int sendsize;
111 	u_int recvsize;
112 {
113 	bool_t madesock = FALSE;
114 	register SVCXPRT *xprt;
115 	register struct tcp_rendezvous *r;
116 	struct sockaddr_in addr;
117 	int len = sizeof (struct sockaddr_in);
118 
119 	if (sock == RPC_ANYSOCK) {
120 		if ((sock = _socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
121 			(void) syslog(LOG_ERR, "svctcp_create - tcp",
122 				" socket creation problem: %m");
123 			return ((SVCXPRT *)NULL);
124 		}
125 		madesock = TRUE;
126 	}
127 	memset((char *)&addr, 0, sizeof (addr));
128 	addr.sin_family = AF_INET;
129 	if (bindresvport(sock, &addr)) {
130 		addr.sin_port = 0;
131 		(void) _bind(sock, (struct sockaddr *)&addr, len);
132 	}
133 	if ((_getsockname(sock, (struct sockaddr *)&addr, &len) != 0) ||
134 	    (_listen(sock, 2) != 0)) {
135 		(void) syslog(LOG_ERR, "svctcp_create - cannot",
136 			" getsockname or listen: %m");
137 		if (madesock)
138 			(void) close(sock);
139 		return ((SVCXPRT *)NULL);
140 	}
141 	r = (struct tcp_rendezvous *)mem_alloc(sizeof (*r));
142 	if (r == NULL) {
143 		(void) syslog(LOG_ERR, "svctcp_create: out of memory");
144 		if (madesock)
145 			(void) close(sock);
146 		return (NULL);
147 	}
148 	r->sendsize = sendsize;
149 	r->recvsize = recvsize;
150 	xprt = svc_xprt_alloc();
151 	if (xprt == NULL) {
152 		(void) syslog(LOG_ERR, "svctcp_create: out of memory");
153 		mem_free((char *) r, sizeof (*r));
154 		if (madesock)
155 			(void) close(sock);
156 		return (NULL);
157 	}
158 	xprt->xp_p2 = NULL;
159 	xprt->xp_netid = NULL;
160 	xprt->xp_p1 = (caddr_t)r;
161 	xprt->xp_verf = _null_auth;
162 	xprt->xp_ops = svctcp_rendezvous_ops();
163 	xprt->xp_port = ntohs(addr.sin_port);
164 	xprt->xp_sock = sock;
165 	xprt->xp_rtaddr.buf = xprt->xp_raddr;
166 	xprt_register(xprt);
167 	return (xprt);
168 }
169 
170 /*
171  * Like svtcp_create(), except the routine takes any *open* UNIX file
172  * descriptor as its first input.
173  */
174 SVCXPRT *
svcfd_create(fd,sendsize,recvsize)175 svcfd_create(fd, sendsize, recvsize)
176 	int fd;
177 	u_int sendsize;
178 	u_int recvsize;
179 {
180 
181 	return (makefd_xprt(fd, sendsize, recvsize));
182 }
183 
184 static SVCXPRT *
makefd_xprt(fd,sendsize,recvsize)185 makefd_xprt(fd, sendsize, recvsize)
186 	int fd;
187 	u_int sendsize;
188 	u_int recvsize;
189 {
190 	register SVCXPRT *xprt;
191 	register struct tcp_conn *cd;
192 
193 	xprt = svc_xprt_alloc();
194 	if (xprt == (SVCXPRT *)NULL) {
195 		(void) syslog(LOG_ERR, "svc_tcp: makefd_xprt: out of memory");
196 		goto done;
197 	}
198 	cd = (struct tcp_conn *)mem_alloc(sizeof (struct tcp_conn));
199 	if (cd == (struct tcp_conn *)NULL) {
200 		(void) syslog(LOG_ERR, "svc_tcp: makefd_xprt: out of memory");
201 		svc_xprt_free(xprt);
202 		xprt = (SVCXPRT *)NULL;
203 		goto done;
204 	}
205 	cd->strm_stat = XPRT_IDLE;
206 	xdrrec_create(&(cd->xdrs), sendsize, recvsize,
207 	    (caddr_t)xprt, readtcp, writetcp);
208 	xprt->xp_p2 = NULL;
209 	xprt->xp_netid = NULL;
210 	xprt->xp_p1 = (caddr_t)cd;
211 	xprt->xp_verf.oa_base = cd->verf_body;
212 	xprt->xp_addrlen = 0;
213 	xprt->xp_ops = svctcp_ops();  /* truely deals with calls */
214 	xprt->xp_port = 0;  /* this is a connection, not a rendezvouser */
215 	xprt->xp_sock = fd;
216 	/* to handle svc_getcaller() properly */
217 	xprt->xp_rtaddr.buf = xprt->xp_raddr;
218 	xprt_register(xprt);
219 	done:
220 	return (xprt);
221 }
222 
223 static bool_t
rendezvous_request(xprt,rpc_msg)224 rendezvous_request(xprt, rpc_msg)
225 	register SVCXPRT *xprt;
226 	struct rpc_msg	*rpc_msg;
227 {
228 	int sock;
229 	struct tcp_rendezvous *r;
230 	struct sockaddr_in addr;
231 	int len;
232 
233 	r = (struct tcp_rendezvous *)xprt->xp_p1;
234 	again:
235 	len = sizeof (struct sockaddr_in);
236 	if ((sock = _accept(xprt->xp_sock, (struct sockaddr *)&addr,
237 	    &len)) < 0) {
238 		if (errno == EINTR)
239 			goto again;
240 		return (FALSE);
241 	}
242 	/*
243 	 * make a new transporter (re-uses xprt)
244 	 */
245 	xprt = makefd_xprt(sock, r->sendsize, r->recvsize);
246 
247 	memcpy((char *)&xprt->xp_raddr, (char *)&addr, len);
248 	xprt->xp_addrlen = len;
249 	return (FALSE); /* there is never an rpc msg to be processed */
250 }
251 
252 static enum xprt_stat
rendezvous_stat(xprt)253 rendezvous_stat(xprt)
254 	SVCXPRT *xprt;
255 {
256 
257 	return (XPRT_IDLE);
258 }
259 
260 static void
svctcp_destroy(xprt)261 svctcp_destroy(xprt)
262 	register SVCXPRT *xprt;
263 {
264 	register struct tcp_conn *cd = (struct tcp_conn *)xprt->xp_p1;
265 
266 	xprt_unregister(xprt);
267 	(void) close(xprt->xp_sock);
268 	if (xprt->xp_port != 0) {
269 		/* a rendezvouser socket */
270 		xprt->xp_port = 0;
271 	} else {
272 		/* an actual connection socket */
273 		XDR_DESTROY(&(cd->xdrs));
274 	}
275 	mem_free((caddr_t)cd, sizeof (struct tcp_conn));
276 	svc_xprt_free(xprt);
277 }
278 
279 /*
280  * All read operations timeout after 35 seconds.
281  * A timeout is fatal for the connection.
282  */
283 static struct timeval wait_per_try = { 35, 0 };
284 
285 /*
286  * reads data from the tcp conection.
287  * any error is fatal and the connection is closed.
288  * (And a read of zero bytes is a half closed stream => error.)
289  */
290 static int
readtcp(xprt,buf,len)291 readtcp(xprt, buf, len)
292 	register SVCXPRT *xprt;
293 	caddr_t buf;
294 	register int len;
295 {
296 	register int sock = xprt->xp_sock;
297 	fd_set mask;
298 	fd_set readfds;
299 
300 	FD_ZERO(&mask);
301 	FD_SET(sock, &mask);
302 	do {
303 		readfds = mask;
304 		if (select(__rpc_dtbsize(), &readfds, NULL, NULL,
305 			&wait_per_try) <= 0) {
306 			if (errno == EINTR) {
307 				continue;
308 			}
309 			goto fatal_err;
310 		}
311 	} while (!FD_ISSET(sock, &readfds));
312 	if ((len = read(sock, buf, len)) > 0) {
313 		return (len);
314 	}
315 fatal_err:
316 	((struct tcp_conn *)(xprt->xp_p1))->strm_stat = XPRT_DIED;
317 	return (-1);
318 }
319 
320 /*
321  * writes data to the tcp connection.
322  * Any error is fatal and the connection is closed.
323  */
324 static int
writetcp(xprt,buf,len)325 writetcp(xprt, buf, len)
326 	register SVCXPRT *xprt;
327 	caddr_t buf;
328 	int len;
329 {
330 	register int i, cnt;
331 
332 	for (cnt = len; cnt > 0; cnt -= i, buf += i) {
333 		if ((i = write(xprt->xp_sock, buf, cnt)) < 0) {
334 			((struct tcp_conn *)(xprt->xp_p1))->strm_stat =
335 			    XPRT_DIED;
336 			return (-1);
337 		}
338 	}
339 	return (len);
340 }
341 
342 static enum xprt_stat
svctcp_stat(xprt)343 svctcp_stat(xprt)
344 	SVCXPRT *xprt;
345 {
346 	register struct tcp_conn *cd =
347 	    (struct tcp_conn *)(xprt->xp_p1);
348 
349 	if (cd->strm_stat == XPRT_DIED)
350 		return (XPRT_DIED);
351 	if (! xdrrec_eof(&(cd->xdrs)))
352 		return (XPRT_MOREREQS);
353 	return (XPRT_IDLE);
354 }
355 
356 static bool_t
svctcp_recv(xprt,msg)357 svctcp_recv(xprt, msg)
358 	SVCXPRT *xprt;
359 	register struct rpc_msg *msg;
360 {
361 	register struct tcp_conn *cd =
362 	    (struct tcp_conn *)(xprt->xp_p1);
363 	register XDR *xdrs = &(cd->xdrs);
364 
365 	xdrs->x_op = XDR_DECODE;
366 	(void) xdrrec_skiprecord(xdrs);
367 	if (xdr_callmsg(xdrs, msg)) {
368 		cd->x_id = msg->rm_xid;
369 		return (TRUE);
370 	}
371 	return (FALSE);
372 }
373 
374 static bool_t
svctcp_getargs(xprt,xdr_args,args_ptr)375 svctcp_getargs(xprt, xdr_args, args_ptr)
376 	SVCXPRT *xprt;
377 	xdrproc_t xdr_args;
378 	caddr_t args_ptr;
379 {
380 
381 	return ((*xdr_args)(&(((struct tcp_conn *)(xprt->xp_p1))->xdrs),
382 		args_ptr));
383 }
384 
385 static bool_t
svctcp_freeargs(xprt,xdr_args,args_ptr)386 svctcp_freeargs(xprt, xdr_args, args_ptr)
387 	SVCXPRT *xprt;
388 	xdrproc_t xdr_args;
389 	caddr_t args_ptr;
390 {
391 	register XDR *xdrs =
392 	    &(((struct tcp_conn *)(xprt->xp_p1))->xdrs);
393 
394 	xdrs->x_op = XDR_FREE;
395 	return ((*xdr_args)(xdrs, args_ptr));
396 }
397 
398 static bool_t
svctcp_reply(xprt,msg)399 svctcp_reply(xprt, msg)
400 	SVCXPRT *xprt;
401 	register struct rpc_msg *msg;
402 {
403 	register struct tcp_conn *cd =
404 	    (struct tcp_conn *)(xprt->xp_p1);
405 	register XDR *xdrs = &(cd->xdrs);
406 	register bool_t stat;
407 
408 	xdrs->x_op = XDR_ENCODE;
409 	msg->rm_xid = cd->x_id;
410 	stat = xdr_replymsg(xdrs, msg);
411 	(void) xdrrec_endofrecord(xdrs, TRUE);
412 	return (stat);
413 }
414 
415 
416 static struct xp_ops *
svctcp_ops()417 svctcp_ops()
418 {
419 	static struct xp_ops ops;
420 
421 	if (ops.xp_recv == NULL) {
422 		ops.xp_recv = svctcp_recv;
423 		ops.xp_stat = svctcp_stat;
424 		ops.xp_getargs = svctcp_getargs;
425 		ops.xp_reply = svctcp_reply;
426 		ops.xp_freeargs = svctcp_freeargs;
427 		ops.xp_destroy = svctcp_destroy;
428 	}
429 	return (&ops);
430 }
431 
432 
433 static struct xp_ops *
svctcp_rendezvous_ops()434 svctcp_rendezvous_ops()
435 {
436 	static struct xp_ops ops;
437 
438 	if (ops.xp_recv == NULL) {
439 		ops.xp_recv = rendezvous_request;
440 		ops.xp_stat = rendezvous_stat;
441 		ops.xp_getargs = abort;
442 		ops.xp_reply = abort;
443 		ops.xp_freeargs = abort,
444 		ops.xp_destroy = svctcp_destroy;
445 	}
446 	return (&ops);
447 }
448