1/*	$OpenBSD: xdr_mem.c,v 1.18 2022/02/14 03:38:59 guenther Exp $ */
2
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
34/*
35 * xdr_mem.h, XDR implementation using memory buffers.
36 *
37 * If you have some data to be interpreted as external data representation
38 * or to be converted to external data representation in a memory buffer,
39 * then this is the package for you.
40 *
41 */
42
43#include <sys/types.h>
44#include <netinet/in.h>
45#include <string.h>
46
47#include <rpc/types.h>
48#include <rpc/xdr.h>
49
50static bool_t	xdrmem_getlong_aligned(XDR *, long *);
51static bool_t	xdrmem_putlong_aligned(XDR *, long *);
52static bool_t	xdrmem_getlong_unaligned(XDR *, long *);
53static bool_t	xdrmem_putlong_unaligned(XDR *, long *);
54static bool_t	xdrmem_getbytes(XDR *, caddr_t, u_int);
55static bool_t	xdrmem_putbytes(XDR *, caddr_t, u_int);
56static u_int	xdrmem_getpos(XDR *); /* XXX w/64-bit pointers, u_int not enough! */
57static bool_t	xdrmem_setpos(XDR *, u_int);
58static int32_t *xdrmem_inline_aligned(XDR *, u_int);
59static int32_t *xdrmem_inline_unaligned(XDR *, u_int);
60static void	xdrmem_destroy(XDR *);
61
62static const struct xdr_ops xdrmem_ops_aligned = {
63	xdrmem_getlong_aligned,
64	xdrmem_putlong_aligned,
65	xdrmem_getbytes,
66	xdrmem_putbytes,
67	xdrmem_getpos,
68	xdrmem_setpos,
69	xdrmem_inline_aligned,
70	xdrmem_destroy,
71	NULL,	/* xdrmem_control */
72};
73
74static const struct xdr_ops xdrmem_ops_unaligned = {
75	xdrmem_getlong_unaligned,
76	xdrmem_putlong_unaligned,
77	xdrmem_getbytes,
78	xdrmem_putbytes,
79	xdrmem_getpos,
80	xdrmem_setpos,
81	xdrmem_inline_unaligned,
82	xdrmem_destroy,
83	NULL,	/* xdrmem_control */
84};
85
86/*
87 * The procedure xdrmem_create initializes a stream descriptor for a
88 * memory buffer.
89 */
90void
91xdrmem_create(XDR *xdrs, caddr_t addr, u_int size, enum xdr_op op)
92{
93
94	xdrs->x_op = op;
95	xdrs->x_ops = ((size_t)addr & (sizeof(int32_t) - 1))
96	    ? &xdrmem_ops_unaligned : &xdrmem_ops_aligned;
97	xdrs->x_private = xdrs->x_base = addr;
98	xdrs->x_handy = size;
99}
100DEF_WEAK(xdrmem_create);
101
102static void
103xdrmem_destroy(XDR *xdrs)
104{
105}
106
107static bool_t
108xdrmem_getlong_aligned(XDR *xdrs, long int *lp)
109{
110
111	if (xdrs->x_handy < sizeof(int32_t))
112		return (FALSE);
113	xdrs->x_handy -= sizeof(int32_t);
114	*lp = ntohl(*(int32_t *)xdrs->x_private);
115	xdrs->x_private += sizeof(int32_t);
116	return (TRUE);
117}
118
119static bool_t
120xdrmem_putlong_aligned(XDR *xdrs, long int *lp)
121{
122
123	if (xdrs->x_handy < sizeof(int32_t))
124		return (FALSE);
125	xdrs->x_handy -= sizeof(int32_t);
126	*(int32_t *)xdrs->x_private = htonl((u_int32_t)*lp);
127	xdrs->x_private += sizeof(int32_t);
128	return (TRUE);
129}
130
131static bool_t
132xdrmem_getlong_unaligned(XDR *xdrs, long int *lp)
133{
134	int32_t l;
135
136	if (xdrs->x_handy < sizeof(int32_t))
137		return (FALSE);
138	xdrs->x_handy -= sizeof(int32_t);
139	memcpy(&l, xdrs->x_private, sizeof(int32_t));
140	*lp = ntohl(l);
141	xdrs->x_private += sizeof(int32_t);
142	return (TRUE);
143}
144
145static bool_t
146xdrmem_putlong_unaligned(XDR *xdrs, long int *lp)
147{
148	int32_t l;
149
150	if (xdrs->x_handy < sizeof(int32_t))
151		return (FALSE);
152	xdrs->x_handy -= sizeof(int32_t);
153	l = htonl((u_int32_t)*lp);
154	memcpy(xdrs->x_private, &l, sizeof(int32_t));
155	xdrs->x_private += sizeof(int32_t);
156	return (TRUE);
157}
158
159static bool_t
160xdrmem_getbytes(XDR *xdrs, caddr_t addr, u_int len)
161{
162
163	if (xdrs->x_handy < len)
164		return (FALSE);
165	xdrs->x_handy -= len;
166	memcpy(addr, xdrs->x_private, len);
167	xdrs->x_private += len;
168	return (TRUE);
169}
170
171static bool_t
172xdrmem_putbytes(XDR *xdrs, caddr_t addr, u_int len)
173{
174
175	if (xdrs->x_handy < len)
176		return (FALSE);
177	xdrs->x_handy -= len;
178	memcpy(xdrs->x_private, addr, len);
179	xdrs->x_private += len;
180	return (TRUE);
181}
182
183static u_int
184xdrmem_getpos(XDR *xdrs)
185{
186
187	/* XXX w/64-bit pointers, u_int not enough! */
188	return ((u_long)xdrs->x_private - (u_long)xdrs->x_base);
189}
190
191static bool_t
192xdrmem_setpos(XDR *xdrs, u_int pos)
193{
194	caddr_t newaddr = xdrs->x_base + pos;
195	caddr_t lastaddr = xdrs->x_private + xdrs->x_handy;
196
197	if (newaddr > lastaddr)
198		return (FALSE);
199	xdrs->x_private = newaddr;
200	xdrs->x_handy = (u_int)(lastaddr - newaddr);	/* XXX w/64-bit pointers, u_int not enough! */
201	return (TRUE);
202}
203
204static int32_t *
205xdrmem_inline_aligned(XDR *xdrs, u_int len)
206{
207	int32_t *buf = 0;
208
209	if (xdrs->x_handy >= len) {
210		xdrs->x_handy -= len;
211		buf = (int32_t *)xdrs->x_private;
212		xdrs->x_private += len;
213	}
214	return (buf);
215}
216
217static int32_t *
218xdrmem_inline_unaligned(XDR *xdrs, u_int len)
219{
220
221	return (0);
222}
223