summaryrefslogtreecommitdiff
path: root/sunrpc/xdr_mem.c
blob: 46a1f6f1903dd961cc30faa7987da49939649f6d (plain)
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
/*
 * xdr_mem.c, XDR implementation using memory buffers.
 *
 * Copyright (c) 2010, Oracle America, Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials
 *       provided with the distribution.
 *     * Neither the name of the "Oracle America, Inc." nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * If you have some data to be interpreted as external data representation
 * or to be converted to external data representation in a memory buffer,
 * then this is the package for you.
 */

#include <string.h>
#include <limits.h>
#include <rpc/rpc.h>
#include <shlib-compat.h>

static bool_t xdrmem_getlong (XDR *, long *);
static bool_t xdrmem_putlong (XDR *, const long *);
static bool_t xdrmem_getbytes (XDR *, caddr_t, u_int);
static bool_t xdrmem_putbytes (XDR *, const char *, u_int);
static u_int xdrmem_getpos (const XDR *);
static bool_t xdrmem_setpos (XDR *, u_int);
static int32_t *xdrmem_inline (XDR *, u_int);
static void xdrmem_destroy (XDR *);
static bool_t xdrmem_getint32 (XDR *, int32_t *);
static bool_t xdrmem_putint32 (XDR *, const int32_t *);

static const struct xdr_ops xdrmem_ops =
{
  xdrmem_getlong,
  xdrmem_putlong,
  xdrmem_getbytes,
  xdrmem_putbytes,
  xdrmem_getpos,
  xdrmem_setpos,
  xdrmem_inline,
  xdrmem_destroy,
  xdrmem_getint32,
  xdrmem_putint32
};

/*
 * The procedure xdrmem_create initializes a stream descriptor for a
 * memory buffer.
 */
void
xdrmem_create (XDR *xdrs, const caddr_t addr, u_int size, enum xdr_op op)
{
  xdrs->x_op = op;
  /* We have to add the const since the `struct xdr_ops' in `struct XDR'
     is not `const'.  */
  xdrs->x_ops = (struct xdr_ops *) &xdrmem_ops;
  xdrs->x_private = xdrs->x_base = addr;
  xdrs->x_handy = size;
}
#ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def (xdrmem_create)
#else
libc_hidden_nolink_sunrpc (xdrmem_create, GLIBC_2_0)
#endif

/*
 * Nothing needs to be done for the memory case.  The argument is clearly
 * const.
 */

static void
xdrmem_destroy (XDR *xdrs)
{
}

/*
 * Gets the next word from the memory referenced by xdrs and places it
 * in the long pointed to by lp.  It then increments the private word to
 * point at the next element.  Neither object pointed to is const
 */
static bool_t
xdrmem_getlong (XDR *xdrs, long *lp)
{
  if (xdrs->x_handy < 4)
    return FALSE;
  xdrs->x_handy -= 4;
  *lp = (int32_t) ntohl ((*((int32_t *) (xdrs->x_private))));
  xdrs->x_private += 4;
  return TRUE;
}

/*
 * Puts the long pointed to by lp in the memory referenced by xdrs.  It
 * then increments the private word to point at the next element.  The
 * long pointed at is const
 */
static bool_t
xdrmem_putlong (XDR *xdrs, const long *lp)
{
  if (xdrs->x_handy < 4)
    return FALSE;
  xdrs->x_handy -= 4;
  *(int32_t *) xdrs->x_private = htonl (*lp);
  xdrs->x_private += 4;
  return TRUE;
}

/*
 * Gets an unaligned number of bytes from the xdrs structure and writes them
 * to the address passed in addr.  Be very careful when calling this routine
 * as it could leave the xdrs pointing to an unaligned structure which is not
 * a good idea.  None of the things pointed to are const.
 */
static bool_t
xdrmem_getbytes (XDR *xdrs, caddr_t addr, u_int len)
{
  if (xdrs->x_handy < len)
    return FALSE;
  xdrs->x_handy -= len;
  memcpy (addr, xdrs->x_private, len);
  xdrs->x_private += len;
  return TRUE;
}

/*
 * The complementary function to the above.  The same warnings apply about
 * unaligned data.  The source address is const.
 */
static bool_t
xdrmem_putbytes (XDR *xdrs, const char *addr, u_int len)
{
  if (xdrs->x_handy < len)
    return FALSE;
  xdrs->x_handy -= len;
  memcpy (xdrs->x_private, addr, len);
  xdrs->x_private += len;
  return TRUE;
}

/*
 * Not sure what this one does.  But it clearly doesn't modify the contents
 * of xdrs.  **FIXME** does this not assume u_int == u_long?
 */
static u_int
xdrmem_getpos (const XDR *xdrs)
{
  return (u_long) xdrs->x_private - (u_long) xdrs->x_base;
}

/*
 * xdrs modified
 */
static bool_t
xdrmem_setpos (XDR *xdrs, u_int pos)
{
  caddr_t newaddr = xdrs->x_base + pos;
  caddr_t lastaddr = xdrs->x_private + xdrs->x_handy;
  size_t handy = lastaddr - newaddr;

  if (newaddr > lastaddr
      || newaddr < xdrs->x_base
      || handy != (u_int) handy)
    return FALSE;

  xdrs->x_private = newaddr;
  xdrs->x_handy = (u_int) handy;
  return TRUE;
}

/*
 * xdrs modified
 */
static int32_t *
xdrmem_inline (XDR *xdrs, u_int len)
{
  int32_t *buf = 0;

  if (xdrs->x_handy >= len)
    {
      xdrs->x_handy -= len;
      buf = (int32_t *) xdrs->x_private;
      xdrs->x_private += len;
    }
  return buf;
}

/*
 * Gets the next word from the memory referenced by xdrs and places it
 * in the int pointed to by ip.  It then increments the private word to
 * point at the next element.  Neither object pointed to is const
 */
static bool_t
xdrmem_getint32 (XDR *xdrs, int32_t *ip)
{
  if (xdrs->x_handy < 4)
    return FALSE;
  xdrs->x_handy -= 4;
  *ip = ntohl ((*((int32_t *) (xdrs->x_private))));
  xdrs->x_private += 4;
  return TRUE;
}

/*
 * Puts the long pointed to by lp in the memory referenced by xdrs.  It
 * then increments the private word to point at the next element.  The
 * long pointed at is const
 */
static bool_t
xdrmem_putint32 (XDR *xdrs, const int32_t *ip)
{
  if (xdrs->x_handy < 4)
    return FALSE;
  xdrs->x_handy -= 4;
  *(int32_t *) xdrs->x_private = htonl (*ip);
  xdrs->x_private += 4;
  return TRUE;
}