1/*
2 * clnt_tcp.c, Implements a TCP/IP based, client side RPC.
3 *
4 * Copyright (c) 2010, Oracle America, Inc.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met:
9 *
10 * * Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * * Redistributions in binary form must reproduce the above
13 * copyright notice, this list of conditions and the following
14 * disclaimer in the documentation and/or other materials
15 * provided with the distribution.
16 * * Neither the name of the "Oracle America, Inc." nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 *
33 * TCP based RPC supports 'batched calls'.
34 * A sequence of calls may be batched-up in a send buffer. The rpc call
35 * return immediately to the client even though the call was not necessarily
36 * sent. The batching occurs if the results' xdr routine is NULL (0) AND
37 * the rpc timeout value is zero (see clnt.h, rpc).
38 *
39 * Clients should NOT casually batch calls that in fact return results; that is,
40 * the server side should be aware that a call is batched and not produce any
41 * return message. Batched calls that produce many result messages can
42 * deadlock (netlock) the client and the server....
43 *
44 * Now go hang yourself.
45 */
46
47#include <netdb.h>
48#include <errno.h>
49#include <stdio.h>
50#include <unistd.h>
51#include <libintl.h>
52#include <rpc/rpc.h>
53#include <sys/poll.h>
54#include <sys/socket.h>
55#include <rpc/pmap_clnt.h>
56#include <wchar.h>
57
58extern u_long _create_xid (void);
59
60#define MCALL_MSG_SIZE 24
61
62struct ct_data
63 {
64 int ct_sock;
65 bool_t ct_closeit;
66 struct timeval ct_wait;
67 bool_t ct_waitset; /* wait set by clnt_control? */
68 struct sockaddr_in ct_addr;
69 struct rpc_err ct_error;
70 char ct_mcall[MCALL_MSG_SIZE]; /* marshalled callmsg */
71 u_int ct_mpos; /* pos after marshal */
72 XDR ct_xdrs;
73 };
74
75static int readtcp (char *, char *, int);
76static int writetcp (char *, char *, int);
77
78static enum clnt_stat clnttcp_call (CLIENT *, u_long, xdrproc_t, caddr_t,
79 xdrproc_t, caddr_t, struct timeval);
80static void clnttcp_abort (void);
81static void clnttcp_geterr (CLIENT *, struct rpc_err *);
82static bool_t clnttcp_freeres (CLIENT *, xdrproc_t, caddr_t);
83static bool_t clnttcp_control (CLIENT *, int, char *);
84static void clnttcp_destroy (CLIENT *);
85
86static const struct clnt_ops tcp_ops =
87{
88 clnttcp_call,
89 clnttcp_abort,
90 clnttcp_geterr,
91 clnttcp_freeres,
92 clnttcp_destroy,
93 clnttcp_control
94};
95
96/*
97 * Create a client handle for a tcp/ip connection.
98 * If *sockp<0, *sockp is set to a newly created TCP socket and it is
99 * connected to raddr. If *sockp non-negative then
100 * raddr is ignored. The rpc/tcp package does buffering
101 * similar to stdio, so the client must pick send and receive buffer sizes,];
102 * 0 => use the default.
103 * If raddr->sin_port is 0, then a binder on the remote machine is
104 * consulted for the right port number.
105 * NB: *sockp is copied into a private area.
106 * NB: It is the clients responsibility to close *sockp.
107 * NB: The rpch->cl_auth is set null authentication. Caller may wish to set this
108 * something more useful.
109 */
110CLIENT *
111clnttcp_create (struct sockaddr_in *raddr, u_long prog, u_long vers,
112 int *sockp, u_int sendsz, u_int recvsz)
113{
114 CLIENT *h;
115 struct ct_data *ct;
116 struct rpc_msg call_msg;
117
118 h = (CLIENT *) mem_alloc (sizeof (*h));
119 ct = (struct ct_data *) mem_alloc (sizeof (*ct));
120 if (h == NULL || ct == NULL)
121 {
122 struct rpc_createerr *ce = &get_rpc_createerr ();
123 (void) __fxprintf (NULL, "%s: %s", __func__, _("out of memory\n"));
124 ce->cf_stat = RPC_SYSTEMERROR;
125 ce->cf_error.re_errno = ENOMEM;
126 goto fooy;
127 }
128
129 /*
130 * If no port number given ask the pmap for one
131 */
132 if (raddr->sin_port == 0)
133 {
134 u_short port;
135 if ((port = pmap_getport (raddr, prog, vers, IPPROTO_TCP)) == 0)
136 {
137 mem_free ((caddr_t) ct, sizeof (struct ct_data));
138 mem_free ((caddr_t) h, sizeof (CLIENT));
139 return ((CLIENT *) NULL);
140 }
141 raddr->sin_port = htons (port);
142 }
143
144 /*
145 * If no socket given, open one
146 */
147 if (*sockp < 0)
148 {
149 *sockp = __socket (AF_INET, SOCK_STREAM, IPPROTO_TCP);
150 (void) bindresvport (*sockp, (struct sockaddr_in *) 0);
151 if ((*sockp < 0)
152 || (__connect (*sockp, (struct sockaddr *) raddr,
153 sizeof (*raddr)) < 0))
154 {
155 struct rpc_createerr *ce = &get_rpc_createerr ();
156 ce->cf_stat = RPC_SYSTEMERROR;
157 ce->cf_error.re_errno = errno;
158 if (*sockp >= 0)
159 (void) __close (*sockp);
160 goto fooy;
161 }
162 ct->ct_closeit = TRUE;
163 }
164 else
165 {
166 ct->ct_closeit = FALSE;
167 }
168
169 /*
170 * Set up private data struct
171 */
172 ct->ct_sock = *sockp;
173 ct->ct_wait.tv_usec = 0;
174 ct->ct_waitset = FALSE;
175 ct->ct_addr = *raddr;
176
177 /*
178 * Initialize call message
179 */
180 call_msg.rm_xid = _create_xid ();
181 call_msg.rm_direction = CALL;
182 call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
183 call_msg.rm_call.cb_prog = prog;
184 call_msg.rm_call.cb_vers = vers;
185
186 /*
187 * pre-serialize the static part of the call msg and stash it away
188 */
189 xdrmem_create (&(ct->ct_xdrs), ct->ct_mcall, MCALL_MSG_SIZE, XDR_ENCODE);
190 if (!xdr_callhdr (&(ct->ct_xdrs), &call_msg))
191 {
192 if (ct->ct_closeit)
193 {
194 (void) __close (*sockp);
195 }
196 goto fooy;
197 }
198 ct->ct_mpos = XDR_GETPOS (&(ct->ct_xdrs));
199 XDR_DESTROY (&(ct->ct_xdrs));
200
201 /*
202 * Create a client handle which uses xdrrec for serialization
203 * and authnone for authentication.
204 */
205 xdrrec_create (&(ct->ct_xdrs), sendsz, recvsz,
206 (caddr_t) ct, readtcp, writetcp);
207 h->cl_ops = (struct clnt_ops *) &tcp_ops;
208 h->cl_private = (caddr_t) ct;
209 h->cl_auth = authnone_create ();
210 return h;
211
212fooy:
213 /*
214 * Something goofed, free stuff and barf
215 */
216 mem_free ((caddr_t) ct, sizeof (struct ct_data));
217 mem_free ((caddr_t) h, sizeof (CLIENT));
218 return ((CLIENT *) NULL);
219}
220#ifdef EXPORT_RPC_SYMBOLS
221libc_hidden_def (clnttcp_create)
222#else
223libc_hidden_nolink_sunrpc (clnttcp_create, GLIBC_2_0)
224#endif
225
226static enum clnt_stat
227clnttcp_call (CLIENT *h, u_long proc, xdrproc_t xdr_args, caddr_t args_ptr,
228 xdrproc_t xdr_results, caddr_t results_ptr,
229 struct timeval timeout)
230{
231 struct ct_data *ct = (struct ct_data *) h->cl_private;
232 XDR *xdrs = &(ct->ct_xdrs);
233 struct rpc_msg reply_msg;
234 u_long x_id;
235 u_int32_t *msg_x_id = (u_int32_t *) (ct->ct_mcall); /* yuk */
236 bool_t shipnow;
237 int refreshes = 2;
238
239 if (!ct->ct_waitset)
240 {
241 ct->ct_wait = timeout;
242 }
243
244 shipnow =
245 (xdr_results == (xdrproc_t) 0 && ct->ct_wait.tv_sec == 0
246 && ct->ct_wait.tv_usec == 0) ? FALSE : TRUE;
247
248call_again:
249 xdrs->x_op = XDR_ENCODE;
250 ct->ct_error.re_status = RPC_SUCCESS;
251 x_id = ntohl (--(*msg_x_id));
252 if ((!XDR_PUTBYTES (xdrs, ct->ct_mcall, ct->ct_mpos)) ||
253 (!XDR_PUTLONG (xdrs, (long *) &proc)) ||
254 (!AUTH_MARSHALL (h->cl_auth, xdrs)) ||
255 (!(*xdr_args) (xdrs, args_ptr)))
256 {
257 if (ct->ct_error.re_status == RPC_SUCCESS)
258 ct->ct_error.re_status = RPC_CANTENCODEARGS;
259 (void) xdrrec_endofrecord (xdrs, TRUE);
260 return (ct->ct_error.re_status);
261 }
262 if (!xdrrec_endofrecord (xdrs, shipnow))
263 return ct->ct_error.re_status = RPC_CANTSEND;
264 if (!shipnow)
265 return RPC_SUCCESS;
266 /*
267 * Hack to provide rpc-based message passing
268 */
269 if (ct->ct_wait.tv_sec == 0 && ct->ct_wait.tv_usec == 0)
270 {
271 return ct->ct_error.re_status = RPC_TIMEDOUT;
272 }
273
274
275 /*
276 * Keep receiving until we get a valid transaction id
277 */
278 xdrs->x_op = XDR_DECODE;
279 while (TRUE)
280 {
281 reply_msg.acpted_rply.ar_verf = _null_auth;
282 reply_msg.acpted_rply.ar_results.where = NULL;
283 reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
284 if (!xdrrec_skiprecord (xdrs))
285 return (ct->ct_error.re_status);
286 /* now decode and validate the response header */
287 if (!xdr_replymsg (xdrs, &reply_msg))
288 {
289 if (ct->ct_error.re_status == RPC_SUCCESS)
290 continue;
291 return ct->ct_error.re_status;
292 }
293 if ((u_int32_t) reply_msg.rm_xid == (u_int32_t) x_id)
294 break;
295 }
296
297 /*
298 * process header
299 */
300 _seterr_reply (&reply_msg, &(ct->ct_error));
301 if (ct->ct_error.re_status == RPC_SUCCESS)
302 {
303 if (!AUTH_VALIDATE (h->cl_auth, &reply_msg.acpted_rply.ar_verf))
304 {
305 ct->ct_error.re_status = RPC_AUTHERROR;
306 ct->ct_error.re_why = AUTH_INVALIDRESP;
307 }
308 else if (!(*xdr_results) (xdrs, results_ptr))
309 {
310 if (ct->ct_error.re_status == RPC_SUCCESS)
311 ct->ct_error.re_status = RPC_CANTDECODERES;
312 }
313 /* free verifier ... */
314 if (reply_msg.acpted_rply.ar_verf.oa_base != NULL)
315 {
316 xdrs->x_op = XDR_FREE;
317 (void) xdr_opaque_auth (xdrs, &(reply_msg.acpted_rply.ar_verf));
318 }
319 } /* end successful completion */
320 else
321 {
322 /* maybe our credentials need to be refreshed ... */
323 if (refreshes-- && AUTH_REFRESH (h->cl_auth))
324 goto call_again;
325 } /* end of unsuccessful completion */
326 return ct->ct_error.re_status;
327}
328
329static void
330clnttcp_geterr (CLIENT *h, struct rpc_err *errp)
331{
332 struct ct_data *ct =
333 (struct ct_data *) h->cl_private;
334
335 *errp = ct->ct_error;
336}
337
338static bool_t
339clnttcp_freeres (CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
340{
341 struct ct_data *ct = (struct ct_data *) cl->cl_private;
342 XDR *xdrs = &(ct->ct_xdrs);
343
344 xdrs->x_op = XDR_FREE;
345 return (*xdr_res) (xdrs, res_ptr);
346}
347
348static void
349clnttcp_abort (void)
350{
351}
352
353static bool_t
354clnttcp_control (CLIENT *cl, int request, char *info)
355{
356 struct ct_data *ct = (struct ct_data *) cl->cl_private;
357 u_long ul;
358 u_int32_t ui32;
359
360
361 switch (request)
362 {
363 case CLSET_FD_CLOSE:
364 ct->ct_closeit = TRUE;
365 break;
366 case CLSET_FD_NCLOSE:
367 ct->ct_closeit = FALSE;
368 break;
369 case CLSET_TIMEOUT:
370 ct->ct_wait = *(struct timeval *) info;
371 ct->ct_waitset = TRUE;
372 break;
373 case CLGET_TIMEOUT:
374 *(struct timeval *) info = ct->ct_wait;
375 break;
376 case CLGET_SERVER_ADDR:
377 *(struct sockaddr_in *) info = ct->ct_addr;
378 break;
379 case CLGET_FD:
380 *(int *)info = ct->ct_sock;
381 break;
382 case CLGET_XID:
383 /*
384 * use the knowledge that xid is the
385 * first element in the call structure *.
386 * This will get the xid of the PREVIOUS call
387 */
388 memcpy (&ui32, ct->ct_mcall, sizeof (ui32));
389 ul = ntohl (ui32);
390 memcpy (info, &ul, sizeof (ul));
391 break;
392 case CLSET_XID:
393 /* This will set the xid of the NEXT call */
394 memcpy (&ul, info, sizeof (ul));
395 ui32 = htonl (ul - 1);
396 memcpy (ct->ct_mcall, &ui32, sizeof (ui32));
397 /* decrement by 1 as clnttcp_call() increments once */
398 break;
399 case CLGET_VERS:
400 /*
401 * This RELIES on the information that, in the call body,
402 * the version number field is the fifth field from the
403 * beginning of the RPC header. MUST be changed if the
404 * call_struct is changed
405 */
406 memcpy (&ui32, ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT, sizeof (ui32));
407 ul = ntohl (ui32);
408 memcpy (info, &ul, sizeof (ul));
409 break;
410 case CLSET_VERS:
411 memcpy (&ul, info, sizeof (ul));
412 ui32 = htonl (ul);
413 memcpy (ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32));
414 break;
415 case CLGET_PROG:
416 /*
417 * This RELIES on the information that, in the call body,
418 * the program number field is the field from the
419 * beginning of the RPC header. MUST be changed if the
420 * call_struct is changed
421 */
422 memcpy (&ui32, ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT, sizeof (ui32));
423 ul = ntohl (ui32);
424 memcpy (info, &ul, sizeof (ul));
425 break;
426 case CLSET_PROG:
427 memcpy (&ul, info, sizeof (ul));
428 ui32 = htonl (ul);
429 memcpy (ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32));
430 break;
431 /* The following are only possible with TI-RPC */
432 case CLGET_RETRY_TIMEOUT:
433 case CLSET_RETRY_TIMEOUT:
434 case CLGET_SVC_ADDR:
435 case CLSET_SVC_ADDR:
436 case CLSET_PUSH_TIMOD:
437 case CLSET_POP_TIMOD:
438 default:
439 return FALSE;
440 }
441 return TRUE;
442}
443
444
445static void
446clnttcp_destroy (CLIENT *h)
447{
448 struct ct_data *ct =
449 (struct ct_data *) h->cl_private;
450
451 if (ct->ct_closeit)
452 {
453 (void) __close (ct->ct_sock);
454 }
455 XDR_DESTROY (&(ct->ct_xdrs));
456 mem_free ((caddr_t) ct, sizeof (struct ct_data));
457 mem_free ((caddr_t) h, sizeof (CLIENT));
458}
459
460/*
461 * Interface between xdr serializer and tcp connection.
462 * Behaves like the system calls, read & write, but keeps some error state
463 * around for the rpc level.
464 */
465static int
466readtcp (char *ctptr, char *buf, int len)
467{
468 struct ct_data *ct = (struct ct_data *)ctptr;
469 struct pollfd fd;
470 int milliseconds = (ct->ct_wait.tv_sec * 1000) +
471 (ct->ct_wait.tv_usec / 1000);
472
473 if (len == 0)
474 return 0;
475
476 fd.fd = ct->ct_sock;
477 fd.events = POLLIN;
478 while (TRUE)
479 {
480 switch (__poll(&fd, 1, milliseconds))
481 {
482 case 0:
483 ct->ct_error.re_status = RPC_TIMEDOUT;
484 return -1;
485
486 case -1:
487 if (errno == EINTR)
488 continue;
489 ct->ct_error.re_status = RPC_CANTRECV;
490 ct->ct_error.re_errno = errno;
491 return -1;
492 }
493 break;
494 }
495 switch (len = __read (ct->ct_sock, buf, len))
496 {
497
498 case 0:
499 /* premature eof */
500 ct->ct_error.re_errno = ECONNRESET;
501 ct->ct_error.re_status = RPC_CANTRECV;
502 len = -1; /* it's really an error */
503 break;
504
505 case -1:
506 ct->ct_error.re_errno = errno;
507 ct->ct_error.re_status = RPC_CANTRECV;
508 break;
509 }
510 return len;
511}
512
513static int
514writetcp (char *ctptr, char *buf, int len)
515{
516 int i, cnt;
517 struct ct_data *ct = (struct ct_data*)ctptr;
518
519 for (cnt = len; cnt > 0; cnt -= i, buf += i)
520 {
521 if ((i = __write (ct->ct_sock, buf, cnt)) == -1)
522 {
523 ct->ct_error.re_errno = errno;
524 ct->ct_error.re_status = RPC_CANTSEND;
525 return -1;
526 }
527 }
528 return len;
529}
530