xref: /openbsd/lib/libc/rpc/xdr_mem.c (revision 8d4335cb)
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 
50 static bool_t	xdrmem_getlong_aligned(XDR *, long *);
51 static bool_t	xdrmem_putlong_aligned(XDR *, long *);
52 static bool_t	xdrmem_getlong_unaligned(XDR *, long *);
53 static bool_t	xdrmem_putlong_unaligned(XDR *, long *);
54 static bool_t	xdrmem_getbytes(XDR *, caddr_t, u_int);
55 static bool_t	xdrmem_putbytes(XDR *, caddr_t, u_int);
56 static u_int	xdrmem_getpos(XDR *); /* XXX w/64-bit pointers, u_int not enough! */
57 static bool_t	xdrmem_setpos(XDR *, u_int);
58 static int32_t *xdrmem_inline_aligned(XDR *, u_int);
59 static int32_t *xdrmem_inline_unaligned(XDR *, u_int);
60 static void	xdrmem_destroy(XDR *);
61 
62 static 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 
74 static 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  */
90 void
xdrmem_create(XDR * xdrs,caddr_t addr,u_int size,enum xdr_op op)91 xdrmem_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 }
100 DEF_WEAK(xdrmem_create);
101 
102 static void
xdrmem_destroy(XDR * xdrs)103 xdrmem_destroy(XDR *xdrs)
104 {
105 }
106 
107 static bool_t
xdrmem_getlong_aligned(XDR * xdrs,long int * lp)108 xdrmem_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 
119 static bool_t
xdrmem_putlong_aligned(XDR * xdrs,long int * lp)120 xdrmem_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 
131 static bool_t
xdrmem_getlong_unaligned(XDR * xdrs,long int * lp)132 xdrmem_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 
145 static bool_t
xdrmem_putlong_unaligned(XDR * xdrs,long int * lp)146 xdrmem_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 
159 static bool_t
xdrmem_getbytes(XDR * xdrs,caddr_t addr,u_int len)160 xdrmem_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 
171 static bool_t
xdrmem_putbytes(XDR * xdrs,caddr_t addr,u_int len)172 xdrmem_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 
183 static u_int
xdrmem_getpos(XDR * xdrs)184 xdrmem_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 
191 static bool_t
xdrmem_setpos(XDR * xdrs,u_int pos)192 xdrmem_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 
204 static int32_t *
xdrmem_inline_aligned(XDR * xdrs,u_int len)205 xdrmem_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 
217 static int32_t *
xdrmem_inline_unaligned(XDR * xdrs,u_int len)218 xdrmem_inline_unaligned(XDR *xdrs, u_int len)
219 {
220 
221 	return (0);
222 }
223