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 | #include <shlib-compat.h> |
58 | |
59 | extern u_long _create_xid (void); |
60 | |
61 | #define MCALL_MSG_SIZE 24 |
62 | |
63 | struct ct_data |
64 | { |
65 | int ct_sock; |
66 | bool_t ct_closeit; |
67 | struct timeval ct_wait; |
68 | bool_t ct_waitset; /* wait set by clnt_control? */ |
69 | struct sockaddr_in ct_addr; |
70 | struct rpc_err ct_error; |
71 | char ct_mcall[MCALL_MSG_SIZE]; /* marshalled callmsg */ |
72 | u_int ct_mpos; /* pos after marshal */ |
73 | XDR ct_xdrs; |
74 | }; |
75 | |
76 | static int readtcp (char *, char *, int); |
77 | static int writetcp (char *, char *, int); |
78 | |
79 | static enum clnt_stat clnttcp_call (CLIENT *, u_long, xdrproc_t, caddr_t, |
80 | xdrproc_t, caddr_t, struct timeval); |
81 | static void clnttcp_abort (void); |
82 | static void clnttcp_geterr (CLIENT *, struct rpc_err *); |
83 | static bool_t clnttcp_freeres (CLIENT *, xdrproc_t, caddr_t); |
84 | static bool_t clnttcp_control (CLIENT *, int, char *); |
85 | static void clnttcp_destroy (CLIENT *); |
86 | |
87 | static const struct clnt_ops tcp_ops = |
88 | { |
89 | clnttcp_call, |
90 | clnttcp_abort, |
91 | clnttcp_geterr, |
92 | clnttcp_freeres, |
93 | clnttcp_destroy, |
94 | clnttcp_control |
95 | }; |
96 | |
97 | /* |
98 | * Create a client handle for a tcp/ip connection. |
99 | * If *sockp<0, *sockp is set to a newly created TCP socket and it is |
100 | * connected to raddr. If *sockp non-negative then |
101 | * raddr is ignored. The rpc/tcp package does buffering |
102 | * similar to stdio, so the client must pick send and receive buffer sizes,]; |
103 | * 0 => use the default. |
104 | * If raddr->sin_port is 0, then a binder on the remote machine is |
105 | * consulted for the right port number. |
106 | * NB: *sockp is copied into a private area. |
107 | * NB: It is the clients responsibility to close *sockp. |
108 | * NB: The rpch->cl_auth is set null authentication. Caller may wish to set this |
109 | * something more useful. |
110 | */ |
111 | CLIENT * |
112 | clnttcp_create (struct sockaddr_in *raddr, u_long prog, u_long vers, |
113 | int *sockp, u_int sendsz, u_int recvsz) |
114 | { |
115 | CLIENT *h; |
116 | struct ct_data *ct; |
117 | struct rpc_msg call_msg; |
118 | |
119 | h = (CLIENT *) mem_alloc (sizeof (*h)); |
120 | ct = (struct ct_data *) mem_alloc (sizeof (*ct)); |
121 | if (h == NULL || ct == NULL) |
122 | { |
123 | struct rpc_createerr *ce = &get_rpc_createerr (); |
124 | (void) __fxprintf (NULL, "%s: %s" , __func__, _("out of memory\n" )); |
125 | ce->cf_stat = RPC_SYSTEMERROR; |
126 | ce->cf_error.re_errno = ENOMEM; |
127 | goto fooy; |
128 | } |
129 | |
130 | /* |
131 | * If no port number given ask the pmap for one |
132 | */ |
133 | if (raddr->sin_port == 0) |
134 | { |
135 | u_short port; |
136 | if ((port = pmap_getport (raddr, prog, vers, IPPROTO_TCP)) == 0) |
137 | { |
138 | mem_free ((caddr_t) ct, sizeof (struct ct_data)); |
139 | mem_free ((caddr_t) h, sizeof (CLIENT)); |
140 | return ((CLIENT *) NULL); |
141 | } |
142 | raddr->sin_port = htons (port); |
143 | } |
144 | |
145 | /* |
146 | * If no socket given, open one |
147 | */ |
148 | if (*sockp < 0) |
149 | { |
150 | *sockp = __socket (AF_INET, SOCK_STREAM, IPPROTO_TCP); |
151 | (void) bindresvport (*sockp, (struct sockaddr_in *) 0); |
152 | if ((*sockp < 0) |
153 | || (__connect (*sockp, (struct sockaddr *) raddr, |
154 | sizeof (*raddr)) < 0)) |
155 | { |
156 | struct rpc_createerr *ce = &get_rpc_createerr (); |
157 | ce->cf_stat = RPC_SYSTEMERROR; |
158 | ce->cf_error.re_errno = errno; |
159 | if (*sockp >= 0) |
160 | (void) __close (*sockp); |
161 | goto fooy; |
162 | } |
163 | ct->ct_closeit = TRUE; |
164 | } |
165 | else |
166 | { |
167 | ct->ct_closeit = FALSE; |
168 | } |
169 | |
170 | /* |
171 | * Set up private data struct |
172 | */ |
173 | ct->ct_sock = *sockp; |
174 | ct->ct_wait.tv_usec = 0; |
175 | ct->ct_waitset = FALSE; |
176 | ct->ct_addr = *raddr; |
177 | |
178 | /* |
179 | * Initialize call message |
180 | */ |
181 | call_msg.rm_xid = _create_xid (); |
182 | call_msg.rm_direction = CALL; |
183 | call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION; |
184 | call_msg.rm_call.cb_prog = prog; |
185 | call_msg.rm_call.cb_vers = vers; |
186 | |
187 | /* |
188 | * pre-serialize the static part of the call msg and stash it away |
189 | */ |
190 | xdrmem_create (&(ct->ct_xdrs), ct->ct_mcall, MCALL_MSG_SIZE, XDR_ENCODE); |
191 | if (!xdr_callhdr (&(ct->ct_xdrs), &call_msg)) |
192 | { |
193 | if (ct->ct_closeit) |
194 | { |
195 | (void) __close (*sockp); |
196 | } |
197 | goto fooy; |
198 | } |
199 | ct->ct_mpos = XDR_GETPOS (&(ct->ct_xdrs)); |
200 | XDR_DESTROY (&(ct->ct_xdrs)); |
201 | |
202 | /* |
203 | * Create a client handle which uses xdrrec for serialization |
204 | * and authnone for authentication. |
205 | */ |
206 | xdrrec_create (&(ct->ct_xdrs), sendsz, recvsz, |
207 | (caddr_t) ct, readtcp, writetcp); |
208 | h->cl_ops = (struct clnt_ops *) &tcp_ops; |
209 | h->cl_private = (caddr_t) ct; |
210 | h->cl_auth = authnone_create (); |
211 | return h; |
212 | |
213 | fooy: |
214 | /* |
215 | * Something goofed, free stuff and barf |
216 | */ |
217 | mem_free ((caddr_t) ct, sizeof (struct ct_data)); |
218 | mem_free ((caddr_t) h, sizeof (CLIENT)); |
219 | return ((CLIENT *) NULL); |
220 | } |
221 | #ifdef EXPORT_RPC_SYMBOLS |
222 | libc_hidden_def (clnttcp_create) |
223 | #else |
224 | libc_hidden_nolink_sunrpc (clnttcp_create, GLIBC_2_0) |
225 | #endif |
226 | |
227 | static enum clnt_stat |
228 | clnttcp_call (CLIENT *h, u_long proc, xdrproc_t xdr_args, caddr_t args_ptr, |
229 | xdrproc_t xdr_results, caddr_t results_ptr, |
230 | struct timeval timeout) |
231 | { |
232 | struct ct_data *ct = (struct ct_data *) h->cl_private; |
233 | XDR *xdrs = &(ct->ct_xdrs); |
234 | struct rpc_msg reply_msg; |
235 | u_long x_id; |
236 | u_int32_t *msg_x_id = (u_int32_t *) (ct->ct_mcall); /* yuk */ |
237 | bool_t shipnow; |
238 | int refreshes = 2; |
239 | |
240 | if (!ct->ct_waitset) |
241 | { |
242 | ct->ct_wait = timeout; |
243 | } |
244 | |
245 | shipnow = |
246 | (xdr_results == (xdrproc_t) 0 && ct->ct_wait.tv_sec == 0 |
247 | && ct->ct_wait.tv_usec == 0) ? FALSE : TRUE; |
248 | |
249 | call_again: |
250 | xdrs->x_op = XDR_ENCODE; |
251 | ct->ct_error.re_status = RPC_SUCCESS; |
252 | x_id = ntohl (--(*msg_x_id)); |
253 | if ((!XDR_PUTBYTES (xdrs, ct->ct_mcall, ct->ct_mpos)) || |
254 | (!XDR_PUTLONG (xdrs, (long *) &proc)) || |
255 | (!AUTH_MARSHALL (h->cl_auth, xdrs)) || |
256 | (!(*xdr_args) (xdrs, args_ptr))) |
257 | { |
258 | if (ct->ct_error.re_status == RPC_SUCCESS) |
259 | ct->ct_error.re_status = RPC_CANTENCODEARGS; |
260 | (void) xdrrec_endofrecord (xdrs, TRUE); |
261 | return (ct->ct_error.re_status); |
262 | } |
263 | if (!xdrrec_endofrecord (xdrs, shipnow)) |
264 | return ct->ct_error.re_status = RPC_CANTSEND; |
265 | if (!shipnow) |
266 | return RPC_SUCCESS; |
267 | /* |
268 | * Hack to provide rpc-based message passing |
269 | */ |
270 | if (ct->ct_wait.tv_sec == 0 && ct->ct_wait.tv_usec == 0) |
271 | { |
272 | return ct->ct_error.re_status = RPC_TIMEDOUT; |
273 | } |
274 | |
275 | |
276 | /* |
277 | * Keep receiving until we get a valid transaction id |
278 | */ |
279 | xdrs->x_op = XDR_DECODE; |
280 | while (TRUE) |
281 | { |
282 | reply_msg.acpted_rply.ar_verf = _null_auth; |
283 | reply_msg.acpted_rply.ar_results.where = NULL; |
284 | reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void; |
285 | if (!xdrrec_skiprecord (xdrs)) |
286 | return (ct->ct_error.re_status); |
287 | /* now decode and validate the response header */ |
288 | if (!xdr_replymsg (xdrs, &reply_msg)) |
289 | { |
290 | if (ct->ct_error.re_status == RPC_SUCCESS) |
291 | continue; |
292 | return ct->ct_error.re_status; |
293 | } |
294 | if ((u_int32_t) reply_msg.rm_xid == (u_int32_t) x_id) |
295 | break; |
296 | } |
297 | |
298 | /* |
299 | * process header |
300 | */ |
301 | _seterr_reply (&reply_msg, &(ct->ct_error)); |
302 | if (ct->ct_error.re_status == RPC_SUCCESS) |
303 | { |
304 | if (!AUTH_VALIDATE (h->cl_auth, &reply_msg.acpted_rply.ar_verf)) |
305 | { |
306 | ct->ct_error.re_status = RPC_AUTHERROR; |
307 | ct->ct_error.re_why = AUTH_INVALIDRESP; |
308 | } |
309 | else if (!(*xdr_results) (xdrs, results_ptr)) |
310 | { |
311 | if (ct->ct_error.re_status == RPC_SUCCESS) |
312 | ct->ct_error.re_status = RPC_CANTDECODERES; |
313 | } |
314 | /* free verifier ... */ |
315 | if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) |
316 | { |
317 | xdrs->x_op = XDR_FREE; |
318 | (void) xdr_opaque_auth (xdrs, &(reply_msg.acpted_rply.ar_verf)); |
319 | } |
320 | } /* end successful completion */ |
321 | else |
322 | { |
323 | /* maybe our credentials need to be refreshed ... */ |
324 | if (refreshes-- && AUTH_REFRESH (h->cl_auth)) |
325 | goto call_again; |
326 | } /* end of unsuccessful completion */ |
327 | return ct->ct_error.re_status; |
328 | } |
329 | |
330 | static void |
331 | clnttcp_geterr (CLIENT *h, struct rpc_err *errp) |
332 | { |
333 | struct ct_data *ct = |
334 | (struct ct_data *) h->cl_private; |
335 | |
336 | *errp = ct->ct_error; |
337 | } |
338 | |
339 | static bool_t |
340 | clnttcp_freeres (CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr) |
341 | { |
342 | struct ct_data *ct = (struct ct_data *) cl->cl_private; |
343 | XDR *xdrs = &(ct->ct_xdrs); |
344 | |
345 | xdrs->x_op = XDR_FREE; |
346 | return (*xdr_res) (xdrs, res_ptr); |
347 | } |
348 | |
349 | static void |
350 | clnttcp_abort (void) |
351 | { |
352 | } |
353 | |
354 | static bool_t |
355 | clnttcp_control (CLIENT *cl, int request, char *info) |
356 | { |
357 | struct ct_data *ct = (struct ct_data *) cl->cl_private; |
358 | u_long ul; |
359 | u_int32_t ui32; |
360 | |
361 | |
362 | switch (request) |
363 | { |
364 | case CLSET_FD_CLOSE: |
365 | ct->ct_closeit = TRUE; |
366 | break; |
367 | case CLSET_FD_NCLOSE: |
368 | ct->ct_closeit = FALSE; |
369 | break; |
370 | case CLSET_TIMEOUT: |
371 | ct->ct_wait = *(struct timeval *) info; |
372 | ct->ct_waitset = TRUE; |
373 | break; |
374 | case CLGET_TIMEOUT: |
375 | *(struct timeval *) info = ct->ct_wait; |
376 | break; |
377 | case CLGET_SERVER_ADDR: |
378 | *(struct sockaddr_in *) info = ct->ct_addr; |
379 | break; |
380 | case CLGET_FD: |
381 | *(int *)info = ct->ct_sock; |
382 | break; |
383 | case CLGET_XID: |
384 | /* |
385 | * use the knowledge that xid is the |
386 | * first element in the call structure *. |
387 | * This will get the xid of the PREVIOUS call |
388 | */ |
389 | memcpy (&ui32, ct->ct_mcall, sizeof (ui32)); |
390 | ul = ntohl (ui32); |
391 | memcpy (info, &ul, sizeof (ul)); |
392 | break; |
393 | case CLSET_XID: |
394 | /* This will set the xid of the NEXT call */ |
395 | memcpy (&ul, info, sizeof (ul)); |
396 | ui32 = htonl (ul - 1); |
397 | memcpy (ct->ct_mcall, &ui32, sizeof (ui32)); |
398 | /* decrement by 1 as clnttcp_call() increments once */ |
399 | break; |
400 | case CLGET_VERS: |
401 | /* |
402 | * This RELIES on the information that, in the call body, |
403 | * the version number field is the fifth field from the |
404 | * beginning of the RPC header. MUST be changed if the |
405 | * call_struct is changed |
406 | */ |
407 | memcpy (&ui32, ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT, sizeof (ui32)); |
408 | ul = ntohl (ui32); |
409 | memcpy (info, &ul, sizeof (ul)); |
410 | break; |
411 | case CLSET_VERS: |
412 | memcpy (&ul, info, sizeof (ul)); |
413 | ui32 = htonl (ul); |
414 | memcpy (ct->ct_mcall + 4 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32)); |
415 | break; |
416 | case CLGET_PROG: |
417 | /* |
418 | * This RELIES on the information that, in the call body, |
419 | * the program number field is the field from the |
420 | * beginning of the RPC header. MUST be changed if the |
421 | * call_struct is changed |
422 | */ |
423 | memcpy (&ui32, ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT, sizeof (ui32)); |
424 | ul = ntohl (ui32); |
425 | memcpy (info, &ul, sizeof (ul)); |
426 | break; |
427 | case CLSET_PROG: |
428 | memcpy (&ul, info, sizeof (ul)); |
429 | ui32 = htonl (ul); |
430 | memcpy (ct->ct_mcall + 3 * BYTES_PER_XDR_UNIT, &ui32, sizeof (ui32)); |
431 | break; |
432 | /* The following are only possible with TI-RPC */ |
433 | case CLGET_RETRY_TIMEOUT: |
434 | case CLSET_RETRY_TIMEOUT: |
435 | case CLGET_SVC_ADDR: |
436 | case CLSET_SVC_ADDR: |
437 | case CLSET_PUSH_TIMOD: |
438 | case CLSET_POP_TIMOD: |
439 | default: |
440 | return FALSE; |
441 | } |
442 | return TRUE; |
443 | } |
444 | |
445 | |
446 | static void |
447 | clnttcp_destroy (CLIENT *h) |
448 | { |
449 | struct ct_data *ct = |
450 | (struct ct_data *) h->cl_private; |
451 | |
452 | if (ct->ct_closeit) |
453 | { |
454 | (void) __close (ct->ct_sock); |
455 | } |
456 | XDR_DESTROY (&(ct->ct_xdrs)); |
457 | mem_free ((caddr_t) ct, sizeof (struct ct_data)); |
458 | mem_free ((caddr_t) h, sizeof (CLIENT)); |
459 | } |
460 | |
461 | /* |
462 | * Interface between xdr serializer and tcp connection. |
463 | * Behaves like the system calls, read & write, but keeps some error state |
464 | * around for the rpc level. |
465 | */ |
466 | static int |
467 | readtcp (char *ctptr, char *buf, int len) |
468 | { |
469 | struct ct_data *ct = (struct ct_data *)ctptr; |
470 | struct pollfd fd; |
471 | int milliseconds = (ct->ct_wait.tv_sec * 1000) + |
472 | (ct->ct_wait.tv_usec / 1000); |
473 | |
474 | if (len == 0) |
475 | return 0; |
476 | |
477 | fd.fd = ct->ct_sock; |
478 | fd.events = POLLIN; |
479 | while (TRUE) |
480 | { |
481 | switch (__poll(&fd, 1, milliseconds)) |
482 | { |
483 | case 0: |
484 | ct->ct_error.re_status = RPC_TIMEDOUT; |
485 | return -1; |
486 | |
487 | case -1: |
488 | if (errno == EINTR) |
489 | continue; |
490 | ct->ct_error.re_status = RPC_CANTRECV; |
491 | ct->ct_error.re_errno = errno; |
492 | return -1; |
493 | } |
494 | break; |
495 | } |
496 | switch (len = __read (ct->ct_sock, buf, len)) |
497 | { |
498 | |
499 | case 0: |
500 | /* premature eof */ |
501 | ct->ct_error.re_errno = ECONNRESET; |
502 | ct->ct_error.re_status = RPC_CANTRECV; |
503 | len = -1; /* it's really an error */ |
504 | break; |
505 | |
506 | case -1: |
507 | ct->ct_error.re_errno = errno; |
508 | ct->ct_error.re_status = RPC_CANTRECV; |
509 | break; |
510 | } |
511 | return len; |
512 | } |
513 | |
514 | static int |
515 | writetcp (char *ctptr, char *buf, int len) |
516 | { |
517 | int i, cnt; |
518 | struct ct_data *ct = (struct ct_data*)ctptr; |
519 | |
520 | for (cnt = len; cnt > 0; cnt -= i, buf += i) |
521 | { |
522 | if ((i = __write (ct->ct_sock, buf, cnt)) == -1) |
523 | { |
524 | ct->ct_error.re_errno = errno; |
525 | ct->ct_error.re_status = RPC_CANTSEND; |
526 | return -1; |
527 | } |
528 | } |
529 | return len; |
530 | } |
531 | |