xref: /illumos-gate/usr/src/lib/libnsl/rpc/xdr_mem.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
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 /*
24  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29 /*
30  * Portions of this source code were derived from Berkeley
31  * 4.3 BSD under license from the Regents of the University of
32  * California.
33  */
34 
35 /*
36  * xdr_mem.h, XDR implementation using memory buffers.
37  *
38  * If you have some data to be interpreted as external data representation
39  * or to be converted to external data representation in a memory buffer,
40  * then this is the package for you.
41  */
42 
43 #include "mt.h"
44 #include "rpc_mt.h"
45 #include <sys/types.h>
46 #include <rpc/types.h>
47 #include <rpc/xdr.h>
48 #include <memory.h>
49 #include <inttypes.h>
50 
51 static struct xdr_ops *xdrmem_ops(void);
52 
53 /*
54  * Meaning of the private areas of the xdr struct for xdr_mem
55  * 	x_base : Base from where the xdr stream starts
56  * 	x_private : The current position of the stream.
57  * 	x_handy : The size of the stream buffer.
58  */
59 
60 /*
61  * The procedure xdrmem_create initializes a stream descriptor for a
62  * memory buffer.
63  */
64 void
65 xdrmem_create(XDR *xdrs, const caddr_t addr, const uint_t size,
66 							const enum xdr_op op)
67 {
68 	caddr_t eaddr = addr;
69 
70 	xdrs->x_op = op;
71 	xdrs->x_ops = xdrmem_ops();
72 	xdrs->x_private = xdrs->x_base = 0;
73 	/*
74 	 * We check here that the size is with in the range of the
75 	 * address space. If not we set x_handy to zero. This will cause
76 	 * all xdrmem entry points to fail.
77 	 */
78 	eaddr = addr + size;
79 
80 	if (eaddr < addr)
81 		xdrs->x_handy = 0;
82 	else {
83 		xdrs->x_handy = size;
84 		xdrs->x_private = xdrs->x_base = addr;
85 	}
86 }
87 
88 /* ARGSUSED */
89 static void
90 xdrmem_destroy(XDR *xdrs)
91 {
92 }
93 
94 static bool_t
95 xdrmem_getlong(XDR *xdrs, long *lp)
96 {
97 	if (sizeof (int32_t) > (uint32_t)xdrs->x_handy) {
98 		xdrs->x_private += (uint_t)xdrs->x_handy;
99 		xdrs->x_handy = 0;
100 		return (FALSE);
101 	}
102 	xdrs->x_handy -= sizeof (int32_t);
103 	/* LINTED pointer cast */
104 	*lp = (int32_t)ntohl((uint32_t)(*((int32_t *)(xdrs->x_private))));
105 	xdrs->x_private += sizeof (int32_t);
106 	return (TRUE);
107 }
108 
109 static bool_t
110 xdrmem_putlong(XDR *xdrs, long *lp)
111 {
112 #if defined(_LP64)
113 	if ((*lp > INT32_MAX) || (*lp < INT32_MIN))
114 		return (FALSE);
115 #endif
116 
117 	if ((sizeof (int32_t) > (uint32_t)xdrs->x_handy)) {
118 		xdrs->x_private += (uint_t)xdrs->x_handy;
119 		xdrs->x_handy = 0;
120 		return (FALSE);
121 	}
122 	xdrs->x_handy -= sizeof (int32_t);
123 	/* LINTED pointer cast */
124 	*(int32_t *)xdrs->x_private = (int32_t)htonl((uint32_t)(*lp));
125 	xdrs->x_private += sizeof (int32_t);
126 	return (TRUE);
127 }
128 
129 #if defined(_LP64)
130 static bool_t
131 xdrmem_getint32(XDR *xdrs, int32_t *ip)
132 {
133 	if (sizeof (int32_t) > (uint_t)xdrs->x_handy) {
134 		xdrs->x_private += (uint_t)xdrs->x_handy;
135 		xdrs->x_handy = 0;
136 		return (FALSE);
137 	}
138 	xdrs->x_handy -= sizeof (int32_t);
139 	/* LINTED pointer cast */
140 	*ip = (int32_t)ntohl((uint32_t)(*((int32_t *)(xdrs->x_private))));
141 	xdrs->x_private += sizeof (int32_t);
142 	return (TRUE);
143 }
144 
145 static bool_t
146 xdrmem_putint32(XDR *xdrs, int32_t *ip)
147 {
148 	if (sizeof (int32_t) > (uint32_t)xdrs->x_handy) {
149 		xdrs->x_private += (uint_t)xdrs->x_handy;
150 		xdrs->x_handy = 0;
151 		return (FALSE);
152 	}
153 	xdrs->x_handy -= sizeof (int32_t);
154 	/* LINTED pointer cast */
155 	*(int32_t *)xdrs->x_private = (int32_t)htonl((uint32_t)(*ip));
156 	xdrs->x_private += sizeof (int32_t);
157 	return (TRUE);
158 }
159 #endif /* _LP64 */
160 
161 static bool_t
162 xdrmem_getbytes(XDR *xdrs, caddr_t addr, int len)
163 {
164 	if ((uint32_t)len > (uint32_t)xdrs->x_handy) {
165 		xdrs->x_private += (uint_t)xdrs->x_handy;
166 		xdrs->x_handy = 0;
167 		return (FALSE);
168 	}
169 	xdrs->x_handy -= len;
170 	(void) memcpy(addr, xdrs->x_private, (uint_t)len);
171 	xdrs->x_private += (uint_t)len;
172 	return (TRUE);
173 }
174 
175 static bool_t
176 xdrmem_putbytes(XDR *xdrs, caddr_t addr, int len)
177 {
178 	if ((uint32_t)len > (uint32_t)xdrs->x_handy) {
179 		xdrs->x_private += (uint_t)xdrs->x_handy;
180 		xdrs->x_handy = 0;
181 		return (FALSE);
182 	}
183 	xdrs->x_handy -= len;
184 	(void) memcpy(xdrs->x_private, addr, (uint_t)len);
185 	xdrs->x_private += (uint_t)len;
186 	return (TRUE);
187 }
188 
189 static uint_t
190 xdrmem_getpos(XDR *xdrs)
191 {
192 	return (uint_t)((uintptr_t)xdrs->x_private - (uintptr_t)xdrs->x_base);
193 }
194 
195 static bool_t
196 xdrmem_setpos(XDR *xdrs, uint_t pos)
197 {
198 	caddr_t newaddr = xdrs->x_base + pos;
199 	caddr_t lastaddr = xdrs->x_private + (uint_t)xdrs->x_handy;
200 
201 	if ((long)newaddr > (long)lastaddr)
202 		return (FALSE);
203 	xdrs->x_private = newaddr;
204 	xdrs->x_handy = (int)((uintptr_t)lastaddr - (uintptr_t)newaddr);
205 	return (TRUE);
206 }
207 
208 static rpc_inline_t *
209 xdrmem_inline(XDR *xdrs, int len)
210 {
211 	rpc_inline_t *buf = 0;
212 
213 	if ((uint32_t)xdrs->x_handy >= (uint32_t)len) {
214 		xdrs->x_handy -= len;
215 		/* LINTED pointer cast */
216 		buf = (rpc_inline_t *)xdrs->x_private;
217 		xdrs->x_private += (uint_t)len;
218 	}
219 	return (buf);
220 }
221 
222 static bool_t
223 xdrmem_control(XDR *xdrs, int request, void *info)
224 {
225 	xdr_bytesrec *xptr;
226 
227 	switch (request) {
228 	case XDR_GET_BYTES_AVAIL:
229 		xptr = (xdr_bytesrec *) info;
230 		xptr->xc_is_last_record = TRUE;
231 		xptr->xc_num_avail = xdrs->x_handy;
232 		return (TRUE);
233 	default:
234 		return (FALSE);
235 
236 	}
237 
238 }
239 
240 static struct xdr_ops *
241 xdrmem_ops(void)
242 {
243 	static struct xdr_ops ops;
244 	extern mutex_t	ops_lock;
245 
246 /* VARIABLES PROTECTED BY ops_lock: ops */
247 	(void) mutex_lock(&ops_lock);
248 	if (ops.x_getlong == NULL) {
249 		ops.x_getlong = xdrmem_getlong;
250 		ops.x_putlong = xdrmem_putlong;
251 		ops.x_getbytes = xdrmem_getbytes;
252 		ops.x_putbytes = xdrmem_putbytes;
253 		ops.x_getpostn = xdrmem_getpos;
254 		ops.x_setpostn = xdrmem_setpos;
255 		ops.x_inline = xdrmem_inline;
256 		ops.x_destroy = xdrmem_destroy;
257 		ops.x_control = xdrmem_control;
258 #if defined(_LP64)
259 		ops.x_getint32 = xdrmem_getint32;
260 		ops.x_putint32 = xdrmem_putint32;
261 #endif
262 	}
263 	(void) mutex_unlock(&ops_lock);
264 	return (&ops);
265 }
266