xref: /illumos-gate/usr/src/uts/common/rpc/xdr_sizeof.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /*
27  * Copyright 2012 Nexenta Systems, Inc. All rights reserved.
28  * Copyright 2017 RackTop Systems.
29  */
30 
31 #include <rpc/types.h>
32 #include <rpc/xdr.h>
33 #include <sys/types.h>
34 
35 /* ARGSUSED */
36 static bool_t
37 x_putint32_t(XDR *xdrs, int32_t *ip)
38 {
39 	xdrs->x_handy += BYTES_PER_XDR_UNIT;
40 	return (TRUE);
41 }
42 
43 /* ARGSUSED */
44 static bool_t
45 x_putbytes(XDR *xdrs, char *bp, int len)
46 {
47 	xdrs->x_handy += len;
48 	return (TRUE);
49 }
50 
51 static uint_t
52 x_getpostn(XDR *xdrs)
53 {
54 	return (xdrs->x_handy);
55 }
56 
57 /* ARGSUSED */
58 static bool_t
59 x_setpostn(XDR *xdrs, uint_t pos)
60 {
61 	/* This is not allowed */
62 	return (FALSE);
63 }
64 
65 static rpc_inline_t *
66 x_inline(XDR *xdrs, int len)
67 {
68 	if (len == 0) {
69 		return (NULL);
70 	}
71 	if (xdrs->x_op != XDR_ENCODE) {
72 		return (NULL);
73 	}
74 	if (len < (uintptr_t)xdrs->x_base) {
75 		/* x_private was already allocated */
76 		xdrs->x_handy += len;
77 		return ((rpc_inline_t *)xdrs->x_private);
78 	} else {
79 		/* Free the earlier space and allocate new area */
80 		if (xdrs->x_private)
81 			mem_free(xdrs->x_private, (uintptr_t)xdrs->x_base);
82 		if ((xdrs->x_private = (caddr_t)mem_alloc(len)) == NULL) {
83 			xdrs->x_base = 0;
84 			return (NULL);
85 		}
86 		xdrs->x_base = (caddr_t)(uintptr_t)len;
87 		xdrs->x_handy += len;
88 		return ((rpc_inline_t *)xdrs->x_private);
89 	}
90 }
91 
92 static int
93 harmless()
94 {
95 	/* Always return FALSE/NULL, as the case may be */
96 	return (0);
97 }
98 
99 static void
100 x_destroy(XDR *xdrs)
101 {
102 	xdrs->x_handy = 0;
103 	if (xdrs->x_private) {
104 		mem_free(xdrs->x_private, (uintptr_t)xdrs->x_base);
105 		xdrs->x_private = NULL;
106 	}
107 	xdrs->x_base = 0;
108 }
109 
110 unsigned int
111 xdr_sizeof(xdrproc_t func, void *data)
112 {
113 	XDR x;
114 	struct xdr_ops ops;
115 	bool_t stat;
116 	/* to stop ANSI-C compiler from complaining */
117 	typedef  bool_t (* dummyfunc1)(XDR *, caddr_t, int);
118 	typedef	 bool_t (* dummyfunc2)(XDR *, int, void *);
119 #if defined(_LP64) || defined(_KERNEL)
120 	typedef  bool_t (* dummyfunc3)(XDR *, int32_t *);
121 #endif
122 
123 	ops.x_putbytes = x_putbytes;
124 	ops.x_inline = x_inline;
125 	ops.x_getpostn = x_getpostn;
126 	ops.x_setpostn = x_setpostn;
127 	ops.x_destroy = x_destroy;
128 
129 #if defined(_LP64) || defined(_KERNEL)
130 	ops.x_getint32 = (dummyfunc3)harmless;
131 	ops.x_putint32 = x_putint32_t;
132 #endif
133 
134 	/* the other harmless ones */
135 	ops.x_getbytes = (dummyfunc1)harmless;
136 	ops.x_control = (dummyfunc2)harmless;
137 
138 	x.x_op = XDR_ENCODE;
139 	x.x_ops = &ops;
140 	x.x_handy = 0;
141 	x.x_private = (caddr_t)NULL;
142 	x.x_base = NULL;
143 
144 	stat = func(&x, data);
145 	if (x.x_private)
146 		mem_free(x.x_private, (uintptr_t)x.x_base);
147 	return (stat == TRUE ? (unsigned int)x.x_handy: 0);
148 }
149