OSX/libsecurityd/lib/sec_xdr_array.c

   1 /*
   2  * Copyright (c) 2006,2011,2013-2014 Apple Inc. All Rights Reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 /*    $NetBSD: xdr_array.c,v 1.12 2000/01/22 22:19:18 mycroft Exp $    */
  25
  26 /*
  27  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  28  * unrestricted use provided that this legend is included on all tape
  29  * media and as a part of the software program in whole or part.  Users
  30  * may copy or modify Sun RPC without charge, but are not authorized
  31  * to license or distribute it to anyone else except as part of a product or
  32  * program developed by the user.
  33  *
  34  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  35  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  36  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  37  *
  38  * Sun RPC is provided with no support and without any obligation on the
  39  * part of Sun Microsystems, Inc. to assist in its use, correction,
  40  * modification or enhancement.
  41  *
  42  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  43  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  44  * OR ANY PART THEREOF.
  45  *
  46  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  47  * or profits or other special, indirect and consequential damages, even if
  48  * Sun has been advised of the possibility of such damages.
  49  *
  50  * Sun Microsystems, Inc.
  51  * 2550 Garcia Avenue
  52  * Mountain View, California  94043
  53  */
  54
  55 #if defined(LIBC_SCCS) && !defined(lint)
  56 static char *sccsid = "@(#)xdr_array.c 1.10 87/08/11 Copyr 1984 Sun Micro";
  57 static char *sccsid = "@(#)xdr_array.c    2.1 88/07/29 4.0 RPCSRC";
  58 #endif
  59 #include <sys/cdefs.h>
  60
  61 /*
  62  * xdr_array.c, Generic XDR routines impelmentation.
  63  *
  64  * Copyright (C) 1984, Sun Microsystems, Inc.
  65  *
  66  * These are the "non-trivial" xdr primitives used to serialize and de-serialize
  67  * arrays.  See xdr.h for more info on the interface to xdr.
  68  */
  69
  70 #include <err.h>
  71 #include <limits.h>
  72 #include <stdio.h>
  73 #include <stdlib.h>
  74 #include <string.h>
  75 #include <assert.h>
  76
  77 #include "sec_xdr.h"
  78
  79 /*
  80  * XDR an array of arbitrary elements
  81  * *addrp is a pointer to the array, *sizep is the number of elements.
  82  * If addrp is NULL (*sizep * elsize) bytes are allocated.
  83  * elsize is the size (in bytes) of each element, and elproc is the
  84  * xdr procedure to call to handle each element of the array.
  85  */
  86 bool_t
  87 sec_xdr_array(XDR *xdrs, uint8_t **addrp, u_int *sizep, u_int maxsize, u_int elsize, xdrproc_t elproc)
  88 {
  89     u_int i;
  90     bool_t stat = TRUE;
  91
  92     u_int c = sizep ? *sizep : 0;  /* the actual element count */
  93     /* like strings, arrays are really counted arrays */
  94     if (!xdr_u_int(xdrs, &c))
  95         return (FALSE);
  96
  97     if (sizep && (xdrs->x_op == XDR_DECODE))
  98         *sizep = c;
  99
 100     // XXX/cs on decode if c == 0 return
 101
 102     if ((c > maxsize || UINT_MAX/elsize < c) && (xdrs->x_op != XDR_FREE))
 103         return (FALSE);
 104
 105     if (elsize > 1024) {
 106         // Structure suspiciously large: 1024 is arbitrary upper bound
 107         // for struct sizes (non-nested size)
 108         assert(FALSE);
 109         return (FALSE);
 110     }
 111
 112     u_int nodesize = c * elsize;
 113     uint8_t *target = addrp ? *addrp : NULL;
 114
 115     uint8_t obj[elsize];
 116
 117     bool_t sizeof_alloc = sec_xdr_arena_size_allocator(xdrs);
 118
 119     /*
 120      * if we are deserializing, we may need to allocate an array.
 121      * We also save time by checking for a null array if we are freeing.
 122      */
 123     if (target == NULL) {
 124         switch (xdrs->x_op) {
 125         case XDR_DECODE:
 126             if (c == 0)
 127                 return (TRUE);
 128                         if (!sec_mem_alloc(xdrs, nodesize, &target))
 129                                 return (FALSE);
 130                         if (!target)
 131                                 target = &obj[0];
 132             if (!sizeof_alloc)
 133                                 *addrp = target;
 134             break;
 135
 136         case XDR_FREE:
 137             return (TRUE);
 138
 139         case XDR_ENCODE:
 140             break;
 141         }
 142     }
 143
 144     /*
 145      * now we xdr each element of array
 146      */
 147     for (i = 0; (i < c) && stat; i++) {
 148         if ((xdrs->x_op == XDR_DECODE) && sizeof_alloc)
 149             memset(obj, 0, elsize);
 150         stat = (*elproc)(xdrs, target, 0);
 151         if ((xdrs->x_op == XDR_ENCODE) || !sizeof_alloc)
 152             target += elsize;
 153     }
 154
 155     /*
 156      * the array may need freeing
 157      */
 158     if (xdrs->x_op == XDR_FREE) {
 159         sec_mem_free(xdrs, *addrp, nodesize);
 160         *addrp = NULL;
 161     }
 162     return (stat);
 163 }
 164
 165 /**
 166  * This is almost a straight copy of the standard implementation, except
 167  * that all calls made that allocate memory can defer to an alternate
 168  * mechanism, with the purpose to allocate from one block of memory on
 169  * *decode*
 170  */