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 | |
58 | extern u_long _create_xid (void); |
59 | |
60 | #define MCALL_MSG_SIZE 24 |
61 | |
62 | struct 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 | |
75 | static int readtcp (char *, char *, int); |
76 | static int writetcp (char *, char *, int); |
77 | |
78 | static enum clnt_stat clnttcp_call (CLIENT *, u_long, xdrproc_t, caddr_t, |
79 | xdrproc_t, caddr_t, struct timeval); |
80 | static void clnttcp_abort (void); |
81 | static void clnttcp_geterr (CLIENT *, struct rpc_err *); |
82 | static bool_t clnttcp_freeres (CLIENT *, xdrproc_t, caddr_t); |
83 | static bool_t clnttcp_control (CLIENT *, int, char *); |
84 | static void clnttcp_destroy (CLIENT *); |
85 | |
86 | static 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 | */ |
110 | CLIENT * |
111 | clnttcp_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 | |
212 | fooy: |
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 |
221 | libc_hidden_def (clnttcp_create) |
222 | #else |
223 | libc_hidden_nolink_sunrpc (clnttcp_create, GLIBC_2_0) |
224 | #endif |
225 | |
226 | static enum clnt_stat |
227 | clnttcp_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 | |
248 | call_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 | |
329 | static void |
330 | clnttcp_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 | |
338 | static bool_t |
339 | clnttcp_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 | |
348 | static void |
349 | clnttcp_abort (void) |
350 | { |
351 | } |
352 | |
353 | static bool_t |
354 | clnttcp_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 | |
445 | static void |
446 | clnttcp_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 | */ |
465 | static int |
466 | readtcp (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 | |
513 | static int |
514 | writetcp (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 | |