1 /* Legacy IPv4 text-to-address functions.
2    Copyright (C) 2019-2022 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, see
17    <https://www.gnu.org/licenses/>.  */
18 
19 /*
20  * Copyright (c) 1983, 1990, 1993
21  *    The Regents of the University of California.  All rights reserved.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the above copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 4. Neither the name of the University nor the names of its contributors
32  *    may be used to endorse or promote products derived from this software
33  *    without specific prior written permission.
34  *
35  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
36  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
38  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
39  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
40  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
41  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
42  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
43  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
44  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
45  * SUCH DAMAGE.
46  */
47 
48 /*
49  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
50  *
51  * Permission to use, copy, modify, and distribute this software for any
52  * purpose with or without fee is hereby granted, provided that the above
53  * copyright notice and this permission notice appear in all copies, and that
54  * the name of Digital Equipment Corporation not be used in advertising or
55  * publicity pertaining to distribution of the document or software without
56  * specific, written prior permission.
57  *
58  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
59  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
60  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
61  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
62  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
63  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
64  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
65  * SOFTWARE.
66  */
67 
68 /*
69  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
70  *
71  * Permission to use, copy, modify, and distribute this software for any
72  * purpose with or without fee is hereby granted, provided that the above
73  * copyright notice and this permission notice appear in all copies.
74  *
75  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
76  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
77  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
78  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
79  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
80  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
81  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
82  * SOFTWARE.
83  */
84 
85 #include <sys/types.h>
86 #include <sys/param.h>
87 
88 #include <netinet/in.h>
89 #include <arpa/inet.h>
90 
91 #include <ctype.h>
92 
93 #include <endian.h>
94 #include <stdint.h>
95 #include <stdlib.h>
96 #include <limits.h>
97 #include <errno.h>
98 
99 /* Check whether "cp" is a valid ASCII representation of an IPv4
100    Internet address and convert it to a binary address.  Returns 1 if
101    the address is valid, 0 if not.  This replaces inet_addr, the
102    return value from which cannot distinguish between failure and a
103    local broadcast address.  Write a pointer to the first
104    non-converted character to *endp.  */
105 static int
inet_aton_end(const char * cp,struct in_addr * addr,const char ** endp)106 inet_aton_end (const char *cp, struct in_addr *addr, const char **endp)
107 {
108   static const in_addr_t max[4] = { 0xffffffff, 0xffffff, 0xffff, 0xff };
109   in_addr_t val;
110   char c;
111   union iaddr
112   {
113     uint8_t bytes[4];
114     uint32_t word;
115   } res;
116   uint8_t *pp = res.bytes;
117   int digit;
118 
119   int saved_errno = errno;
120   __set_errno (0);
121 
122   res.word = 0;
123 
124   c = *cp;
125   for (;;)
126     {
127       /* Collect number up to ``.''.  Values are specified as for C:
128 	 0x=hex, 0=octal, isdigit=decimal.  */
129       if (!isdigit (c))
130 	goto ret_0;
131       {
132 	char *endp;
133 	unsigned long ul = strtoul (cp, &endp, 0);
134 	if (ul == ULONG_MAX && errno == ERANGE)
135 	  goto ret_0;
136 	if (ul > 0xfffffffful)
137 	  goto ret_0;
138 	val = ul;
139 	digit = cp != endp;
140 	cp = endp;
141       }
142       c = *cp;
143       if (c == '.')
144 	{
145 	  /* Internet format:
146 	     a.b.c.d
147 	     a.b.c	(with c treated as 16 bits)
148 	     a.b	(with b treated as 24 bits).  */
149 	  if (pp > res.bytes + 2 || val > 0xff)
150 	    goto ret_0;
151 	  *pp++ = val;
152 	  c = *++cp;
153 	}
154       else
155 	break;
156     }
157   /* Check for trailing characters.  */
158   if (c != '\0' && (!isascii (c) || !isspace (c)))
159     goto ret_0;
160   /*  Did we get a valid digit?  */
161   if (!digit)
162     goto ret_0;
163 
164   /* Check whether the last part is in its limits depending on the
165      number of parts in total.  */
166   if (val > max[pp - res.bytes])
167     goto ret_0;
168 
169   if (addr != NULL)
170     addr->s_addr = res.word | htonl (val);
171   *endp = cp;
172 
173   __set_errno (saved_errno);
174   return 1;
175 
176  ret_0:
177   __set_errno (saved_errno);
178   return 0;
179 }
180 
181 int
__inet_aton_exact(const char * cp,struct in_addr * addr)182 __inet_aton_exact (const char *cp, struct in_addr *addr)
183 {
184   struct in_addr val;
185   const char *endp;
186   /* Check that inet_aton_end parsed the entire string.  */
187   if (inet_aton_end (cp, &val, &endp) != 0 && *endp == 0)
188     {
189       *addr = val;
190       return 1;
191     }
192   else
193     return 0;
194 }
libc_hidden_def(__inet_aton_exact)195 libc_hidden_def (__inet_aton_exact)
196 
197 /* inet_aton ignores trailing garbage.  */
198 int
199 __inet_aton_ignore_trailing (const char *cp, struct in_addr *addr)
200 {
201   const char *endp;
202   return  inet_aton_end (cp, addr, &endp);
203 }
weak_alias(__inet_aton_ignore_trailing,inet_aton)204 weak_alias (__inet_aton_ignore_trailing, inet_aton)
205 
206 /* ASCII IPv4 Internet address interpretation routine.  The value
207    returned is in network order.  */
208 in_addr_t
209 __inet_addr (const char *cp)
210 {
211   struct in_addr val;
212   const char *endp;
213   if (inet_aton_end (cp, &val, &endp))
214     return val.s_addr;
215   return INADDR_NONE;
216 }
217 weak_alias (__inet_addr, inet_addr)
218