safec  2.1
Safe C Library - ISO TR24731 Bounds Checking Interface
strishex_s.c
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1 /*------------------------------------------------------------------
2  * strishex_s.c
3  *
4  * October 2008, Bo Berry
5  *
6  * Copyright (c) 2008-2011, 2013 by Cisco Systems, Inc
7  * All rights reserved.
8  *
9  * Permission is hereby granted, free of charge, to any person
10  * obtaining a copy of this software and associated documentation
11  * files (the "Software"), to deal in the Software without
12  * restriction, including without limitation the rights to use,
13  * copy, modify, merge, publish, distribute, sublicense, and/or
14  * sell copies of the Software, and to permit persons to whom the
15  * Software is furnished to do so, subject to the following
16  * conditions:
17  *
18  * The above copyright notice and this permission notice shall be
19  * included in all copies or substantial portions of the Software.
20  *
21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
23  * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
25  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
26  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
27  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28  * OTHER DEALINGS IN THE SOFTWARE.
29  *------------------------------------------------------------------
30  */
31 
32 #include "safeclib_private.h"
33 #include "safe_str_constraint.h"
34 #include "safe_str_lib.h"
35 
36 
64 bool
65 strishex_s (const char *dest, rsize_t dmax)
66 {
67  if (!dest) {
68  invoke_safe_str_constraint_handler("strishex_s: dest is null",
69  NULL, ESNULLP);
70  return (false);
71  }
72 
73  if (dmax == 0) {
74  invoke_safe_str_constraint_handler("strishex_s: dmax is 0",
75  NULL, ESZEROL);
76  return (false);
77  }
78 
79  if (dmax > RSIZE_MAX_STR) {
80  invoke_safe_str_constraint_handler("strishex_s: dmax exceeds max",
81  NULL, ESLEMAX);
82  return (false);
83  }
84 
85  if (*dest == '\0') {
86  return (false);
87  }
88 
89  while (*dest && dmax) {
90 
91  if (((*dest >= '0') && (*dest <= '9')) ||
92  ((*dest >= 'a') && (*dest <= 'f')) ||
93  ((*dest >= 'A') && (*dest <= 'F'))) {
94  dest++;
95  dmax--;
96 
97  } else {
98  return (false);
99  }
100  }
101 
102  return (true);
103 }
void invoke_safe_str_constraint_handler(const char *msg, void *ptr, errno_t error)
Invokes the currently set constraint handler or the default.
bool strishex_s(const char *dest, rsize_t dmax)
This function checks that the entire string contains hex characters.
Definition: strishex_s.c:65