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_reference.c,v 1.13 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  #include <sys/cdefs.h>
 56  #if defined(LIBC_SCCS) && !defined(lint) 
 57  static char *sccsid = "@(#)xdr_reference.c 1.11 87/08/11 SMI";
 58  static char *sccsid = "@(#)xdr_reference.c      2.1 88/07/29 4.0 RPCSRC";
 59  static char *rcsid = "$FreeBSD: src/lib/libc/xdr/xdr_reference.c,v 1.11 2002/03/22 21:53:26 obrien Exp $";
 60  #endif
 61  #include <sys/cdefs.h>
 62  #include <security_utilities/simulatecrash_assert.h>
 63  /*
 64   * xdr_reference.c, Generic XDR routines impelmentation.
 65   *
 66   * Copyright (C) 1987, Sun Microsystems, Inc.
 67   *
 68   * These are the "non-trivial" xdr primitives used to serialize and de-serialize
 69   * "pointers".  See xdr.h for more info on the interface to xdr.
 70   */
 71  
 72  #include <err.h>
 73  #include <stdio.h>
 74  #include <stdlib.h>
 75  #include <string.h>
 76  
 77  #include "sec_xdr.h"
 78  
 79  /*
 80   * XDR an indirect pointer
 81   * xdr_reference is for recursively translating a structure that is
 82   * referenced by a pointer inside the structure that is currently being
 83   * translated.  pp references a pointer to storage. If *pp is null
 84   * the  necessary storage is allocated.
 85   * size is the sizeof the referneced structure.
 86   * proc is the routine to handle the referenced structure.
 87   */
 88  bool_t
 89  sec_xdr_reference(XDR *xdrs, uint8_t **pp, u_int size, xdrproc_t proc)
 90  {
 91      uint8_t *loc = pp ? *pp : NULL;
 92      bool_t stat;
 93  
 94      if (size > 1024) {
 95          // Structure suspiciously large: 1024 is arbitrary upper bound
 96          // for struct sizes (non-nested size)
 97          assert(FALSE);
 98          return (FALSE);
 99      }
100      uint8_t obj[size];
101  
102      bool_t sizeof_alloc = sec_xdr_arena_size_allocator(xdrs);
103  
104      if (loc == NULL)
105              switch (xdrs->x_op) {
106              case XDR_FREE:
107                  return (TRUE);
108              case XDR_DECODE:
109                  {
110                      if (!sec_mem_alloc(xdrs, size, &loc))
111                          return (FALSE);
112  					if (!loc) {
113                          memset(obj, 0, size);
114  						loc = &obj[0];
115                      }
116  					if (!sizeof_alloc && pp != NULL)
117  						*pp = loc;
118  					break;
119                  }
120              case XDR_ENCODE:
121                  break;
122              }
123  
124      stat = (*proc)(xdrs, loc, 0);
125  
126      if (xdrs->x_op == XDR_FREE) {
127          sec_mem_free(xdrs, loc, size);
128          if(pp) {
129              *pp = NULL;
130          }
131      }
132      return (stat);
133  }
134  
135  
136  bool_t
137  sec_xdr_pointer(XDR *xdrs, uint8_t **objpp, u_int obj_size, xdrproc_t xdr_obj)
138  {
139      bool_t more_data;
140  
141      more_data = (objpp ? (*objpp != NULL) : FALSE);
142      if (! xdr_bool(xdrs,&more_data))
143          return (FALSE);
144  
145      bool_t sizeof_alloc = sec_xdr_arena_size_allocator(xdrs);
146  
147      if (! more_data) {
148          if ((xdrs->x_op == XDR_DECODE) && !sizeof_alloc && objpp != NULL)
149              *objpp = NULL;
150          return (TRUE);
151      }
152      return (sec_xdr_reference(xdrs,objpp,obj_size,xdr_obj));
153  }
154  
155  /**
156   * This is almost a straight copy of the standard implementation, except
157   * that all calls made that allocate memory can defer to an alternate 
158   * mechanism, with the purpose to allocate from one block of memory on
159   * *decode*
160   */