1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
|
/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: svc_udp.c,v 1.8 1998/03/19 00:27:26 millert Exp $";
#endif /* LIBC_SCCS and not lint */
/*
* svc_udp.c,
* Server side for UDP/IP based RPC. (Does some caching in the hopes of
* achieving execute-at-most-once semantics.)
*
* Copyright (C) 1984, Sun Microsystems, Inc.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <errno.h>
#include <unistd.h>
#define rpc_buffer(xprt) ((xprt)->xp_p1)
#define MAX(a, b) ((a > b) ? a : b)
static bool_t svcudp_recv();
static bool_t svcudp_reply();
static enum xprt_stat svcudp_stat();
static bool_t svcudp_getargs();
static bool_t svcudp_freeargs();
static void svcudp_destroy();
static void cache_set __P((SVCXPRT *, u_long));
static int cache_get __P((SVCXPRT *, struct rpc_msg *, char **, u_long *));
static struct xp_ops svcudp_op = {
svcudp_recv,
svcudp_stat,
svcudp_getargs,
svcudp_reply,
svcudp_freeargs,
svcudp_destroy
};
/*
* kept in xprt->xp_p2
*/
struct svcudp_data {
u_int su_iosz; /* byte size of send.recv buffer */
u_long su_xid; /* transaction id */
XDR su_xdrs; /* XDR handle */
char su_verfbody[MAX_AUTH_BYTES]; /* verifier body */
char * su_cache; /* cached data, NULL if no cache */
};
#define su_data(xprt) ((struct svcudp_data *)(xprt->xp_p2))
/*
* Usage:
* xprt = svcudp_create(sock);
*
* If sock<0 then a socket is created, else sock is used.
* If the socket, sock is not bound to a port then svcudp_create
* binds it to an arbitrary port. In any (successful) case,
* xprt->xp_sock is the registered socket number and xprt->xp_port is the
* associated port number.
* Once *xprt is initialized, it is registered as a transporter;
* see (svc.h, xprt_register).
* The routines returns NULL if a problem occurred.
*/
SVCXPRT *
svcudp_bufcreate(sock, sendsz, recvsz)
register int sock;
u_int sendsz, recvsz;
{
bool_t madesock = FALSE;
register SVCXPRT *xprt;
register struct svcudp_data *su;
struct sockaddr_in addr;
int len = sizeof(struct sockaddr_in);
if (sock == RPC_ANYSOCK) {
if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
perror("svcudp_create: socket creation problem");
return ((SVCXPRT *)NULL);
}
madesock = TRUE;
}
memset(&addr, 0, sizeof (addr));
addr.sin_len = sizeof(struct sockaddr_in);
addr.sin_family = AF_INET;
if (bindresvport(sock, &addr)) {
addr.sin_port = 0;
(void)bind(sock, (struct sockaddr *)&addr, len);
}
if (getsockname(sock, (struct sockaddr *)&addr, &len) != 0) {
perror("svcudp_create - cannot getsockname");
if (madesock)
(void)close(sock);
return ((SVCXPRT *)NULL);
}
xprt = (SVCXPRT *)mem_alloc(sizeof(SVCXPRT));
if (xprt == NULL) {
(void)fprintf(stderr, "svcudp_create: out of memory\n");
if (madesock)
(void)close(sock);
return (NULL);
}
su = (struct svcudp_data *)mem_alloc(sizeof(*su));
if (su == NULL) {
(void)fprintf(stderr, "svcudp_create: out of memory\n");
if (madesock)
(void)close(sock);
free(xprt);
return (NULL);
}
su->su_iosz = ((MAX(sendsz, recvsz) + 3) / 4) * 4;
if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL) {
(void)fprintf(stderr, "svcudp_create: out of memory\n");
if (madesock)
(void)close(sock);
free(xprt);
free(su);
return (NULL);
}
xdrmem_create(
&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_DECODE);
su->su_cache = NULL;
xprt->xp_p2 = (caddr_t)su;
xprt->xp_verf.oa_base = su->su_verfbody;
xprt->xp_ops = &svcudp_op;
xprt->xp_port = ntohs(addr.sin_port);
xprt->xp_sock = sock;
xprt_register(xprt);
return (xprt);
}
SVCXPRT *
svcudp_create(sock)
int sock;
{
return(svcudp_bufcreate(sock, UDPMSGSIZE, UDPMSGSIZE));
}
/* ARGSUSED */
static enum xprt_stat
svcudp_stat(xprt)
SVCXPRT *xprt;
{
return (XPRT_IDLE);
}
static bool_t
svcudp_recv(xprt, msg)
register SVCXPRT *xprt;
struct rpc_msg *msg;
{
register struct svcudp_data *su = su_data(xprt);
register XDR *xdrs = &(su->su_xdrs);
register int rlen;
char *reply;
u_long replylen;
again:
xprt->xp_addrlen = sizeof(struct sockaddr_in);
rlen = recvfrom(xprt->xp_sock, rpc_buffer(xprt), (int) su->su_iosz,
0, (struct sockaddr *)&(xprt->xp_raddr), &(xprt->xp_addrlen));
if (rlen == -1 && errno == EINTR)
goto again;
if (rlen == -1 || rlen < 4*sizeof(u_int32_t))
return (FALSE);
xdrs->x_op = XDR_DECODE;
XDR_SETPOS(xdrs, 0);
if (! xdr_callmsg(xdrs, msg))
return (FALSE);
su->su_xid = msg->rm_xid;
if (su->su_cache != NULL) {
if (cache_get(xprt, msg, &reply, &replylen)) {
(void) sendto(xprt->xp_sock, reply, (int) replylen, 0,
(struct sockaddr *) &xprt->xp_raddr, xprt->xp_addrlen);
return (TRUE);
}
}
return (TRUE);
}
static bool_t
svcudp_reply(xprt, msg)
register SVCXPRT *xprt;
struct rpc_msg *msg;
{
register struct svcudp_data *su = su_data(xprt);
register XDR *xdrs = &(su->su_xdrs);
register int slen;
register bool_t stat = FALSE;
xdrs->x_op = XDR_ENCODE;
XDR_SETPOS(xdrs, 0);
msg->rm_xid = su->su_xid;
if (xdr_replymsg(xdrs, msg)) {
slen = (int)XDR_GETPOS(xdrs);
if (sendto(xprt->xp_sock, rpc_buffer(xprt), slen, 0,
(struct sockaddr *)&(xprt->xp_raddr), xprt->xp_addrlen)
== slen) {
stat = TRUE;
if (su->su_cache && slen >= 0) {
cache_set(xprt, (u_long) slen);
}
}
}
return (stat);
}
static bool_t
svcudp_getargs(xprt, xdr_args, args_ptr)
SVCXPRT *xprt;
xdrproc_t xdr_args;
caddr_t args_ptr;
{
return ((*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr));
}
static bool_t
svcudp_freeargs(xprt, xdr_args, args_ptr)
SVCXPRT *xprt;
xdrproc_t xdr_args;
caddr_t args_ptr;
{
register XDR *xdrs = &(su_data(xprt)->su_xdrs);
xdrs->x_op = XDR_FREE;
return ((*xdr_args)(xdrs, args_ptr));
}
static void
svcudp_destroy(xprt)
register SVCXPRT *xprt;
{
register struct svcudp_data *su = su_data(xprt);
xprt_unregister(xprt);
if (xprt->xp_sock != -1)
(void)close(xprt->xp_sock);
xprt->xp_sock = -1;
XDR_DESTROY(&(su->su_xdrs));
mem_free(rpc_buffer(xprt), su->su_iosz);
mem_free((caddr_t)su, sizeof(struct svcudp_data));
mem_free((caddr_t)xprt, sizeof(SVCXPRT));
}
/***********this could be a separate file*********************/
/*
* Fifo cache for udp server
* Copies pointers to reply buffers into fifo cache
* Buffers are sent again if retransmissions are detected.
*/
#define SPARSENESS 4 /* 75% sparse */
#define CACHE_PERROR(msg) \
(void) fprintf(stderr,"%s\n", msg)
#define ALLOC(type, size) \
(type *) mem_alloc((unsigned) (sizeof(type) * (size)))
#define BZERO(addr, type, size) \
memset((char *) addr, 0, sizeof(type) * (int) (size))
/*
* An entry in the cache
*/
typedef struct cache_node *cache_ptr;
struct cache_node {
/*
* Index into cache is xid, proc, vers, prog and address
*/
u_long cache_xid;
u_long cache_proc;
u_long cache_vers;
u_long cache_prog;
struct sockaddr_in cache_addr;
/*
* The cached reply and length
*/
char * cache_reply;
u_long cache_replylen;
/*
* Next node on the list, if there is a collision
*/
cache_ptr cache_next;
};
/*
* The entire cache
*/
struct udp_cache {
u_long uc_size; /* size of cache */
cache_ptr *uc_entries; /* hash table of entries in cache */
cache_ptr *uc_fifo; /* fifo list of entries in cache */
u_long uc_nextvictim; /* points to next victim in fifo list */
u_long uc_prog; /* saved program number */
u_long uc_vers; /* saved version number */
u_long uc_proc; /* saved procedure number */
struct sockaddr_in uc_addr; /* saved caller's address */
};
/*
* the hashing function
*/
#define CACHE_LOC(transp, xid) \
(xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
/*
* Enable use of the cache.
* Note: there is no disable.
*/
int
svcudp_enablecache(transp, size)
SVCXPRT *transp;
u_long size;
{
struct svcudp_data *su = su_data(transp);
struct udp_cache *uc;
if (su->su_cache != NULL) {
CACHE_PERROR("enablecache: cache already enabled");
return(0);
}
uc = ALLOC(struct udp_cache, 1);
if (uc == NULL) {
CACHE_PERROR("enablecache: could not allocate cache");
return(0);
}
uc->uc_size = size;
uc->uc_nextvictim = 0;
uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
if (uc->uc_entries == NULL) {
CACHE_PERROR("enablecache: could not allocate cache data");
return(0);
}
BZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
uc->uc_fifo = ALLOC(cache_ptr, size);
if (uc->uc_fifo == NULL) {
CACHE_PERROR("enablecache: could not allocate cache fifo");
return(0);
}
BZERO(uc->uc_fifo, cache_ptr, size);
su->su_cache = (char *) uc;
return(1);
}
/*
* Set an entry in the cache
*/
static void
cache_set(xprt, replylen)
SVCXPRT *xprt;
u_long replylen;
{
register cache_ptr victim;
register cache_ptr *vicp;
register struct svcudp_data *su = su_data(xprt);
struct udp_cache *uc = (struct udp_cache *) su->su_cache;
u_int loc;
char *newbuf;
/*
* Find space for the new entry, either by
* reusing an old entry, or by mallocing a new one
*/
victim = uc->uc_fifo[uc->uc_nextvictim];
if (victim != NULL) {
loc = CACHE_LOC(xprt, victim->cache_xid);
for (vicp = &uc->uc_entries[loc];
*vicp != NULL && *vicp != victim;
vicp = &(*vicp)->cache_next)
;
if (*vicp == NULL) {
CACHE_PERROR("cache_set: victim not found");
return;
}
*vicp = victim->cache_next; /* remote from cache */
newbuf = victim->cache_reply;
} else {
victim = ALLOC(struct cache_node, 1);
if (victim == NULL) {
CACHE_PERROR("cache_set: victim alloc failed");
return;
}
newbuf = mem_alloc(su->su_iosz);
if (newbuf == NULL) {
CACHE_PERROR("cache_set: could not allocate new rpc_buffer");
return;
}
}
/*
* Store it away
*/
victim->cache_replylen = replylen;
victim->cache_reply = rpc_buffer(xprt);
rpc_buffer(xprt) = newbuf;
xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_ENCODE);
victim->cache_xid = su->su_xid;
victim->cache_proc = uc->uc_proc;
victim->cache_vers = uc->uc_vers;
victim->cache_prog = uc->uc_prog;
victim->cache_addr = uc->uc_addr;
loc = CACHE_LOC(xprt, victim->cache_xid);
victim->cache_next = uc->uc_entries[loc];
uc->uc_entries[loc] = victim;
uc->uc_fifo[uc->uc_nextvictim++] = victim;
uc->uc_nextvictim %= uc->uc_size;
}
/*
* Try to get an entry from the cache
* return 1 if found, 0 if not found
*/
static int
cache_get(xprt, msg, replyp, replylenp)
SVCXPRT *xprt;
struct rpc_msg *msg;
char **replyp;
u_long *replylenp;
{
u_int loc;
register cache_ptr ent;
register struct svcudp_data *su = su_data(xprt);
register struct udp_cache *uc = (struct udp_cache *) su->su_cache;
# define EQADDR(a1, a2) (memcmp(&a1, &a2, sizeof(a1)) == 0)
loc = CACHE_LOC(xprt, su->su_xid);
for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
if (ent->cache_xid == su->su_xid &&
ent->cache_proc == uc->uc_proc &&
ent->cache_vers == uc->uc_vers &&
ent->cache_prog == uc->uc_prog &&
EQADDR(ent->cache_addr, uc->uc_addr)) {
*replyp = ent->cache_reply;
*replylenp = ent->cache_replylen;
return(1);
}
}
/*
* Failed to find entry
* Remember a few things so we can do a set later
*/
uc->uc_proc = msg->rm_call.cb_proc;
uc->uc_vers = msg->rm_call.cb_vers;
uc->uc_prog = msg->rm_call.cb_prog;
uc->uc_addr = xprt->xp_raddr;
return(0);
}
|