1 /* src/port/inet_aton.c
2  *
3  *	This inet_aton() function was taken from the GNU C library and
4  *	incorporated into Postgres for those systems which do not have this
5  *	routine in their standard C libraries.
6  *
7  *	The function was been extracted whole from the file inet_aton.c in
8  *	Release 5.3.12 of the Linux C library, which is derived from the
9  *	GNU C library, by Bryan Henderson in October 1996.  The copyright
10  *	notice from that file is below.
11  */
12 
13 /*
14  * Copyright (c) 1983, 1990, 1993
15  *		The Regents of the University of California.  All rights reserved.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
name(this: &IdbMutableFile) -> String20  * 1. Redistributions of source code must retain the above copyright
21  *	  notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *	  notice, this list of conditions and the following disclaimer in the
24  *	  documentation and/or other materials provided with the distribution.
25  * 3. Neither the name of the University nor the names of its contributors
26  *	  may be used to endorse or promote products derived from this software
27  *	  without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.  */
40 
41 #include "c.h"
42 
43 #include <netinet/in.h>
44 #include <ctype.h>
45 
46 #include "port/pg_bswap.h"
47 
48 /*
49  * Check whether "cp" is a valid ascii representation
50  * of an Internet address and convert to a binary address.
51  * Returns 1 if the address is valid, 0 if not.
52  * This replaces inet_addr, the return value from which
53  * cannot distinguish between failure and a local broadcast address.
54  */
55 int
56 inet_aton(const char *cp, struct in_addr *addr)
57 {
58 	unsigned int val;
59 	int			base,
60 				n;
61 	char		c;
62 	u_int		parts[4];
63 	u_int	   *pp = parts;
64 
65 	for (;;)
66 	{
67 		/*
68 		 * Collect number up to ``.''. Values are specified as for C: 0x=hex,
69 		 * 0=octal, other=decimal.
70 		 */
71 		val = 0;
72 		base = 10;
73 		if (*cp == '0')
74 		{
75 			if (*++cp == 'x' || *cp == 'X')
76 				base = 16, cp++;
77 			else
78 				base = 8;
79 		}
80 		while ((c = *cp) != '\0')
81 		{
82 			if (isdigit((unsigned char) c))
83 			{
84 				val = (val * base) + (c - '0');
85 				cp++;
86 				continue;
87 			}
88 			if (base == 16 && isxdigit((unsigned char) c))
89 			{
90 				val = (val << 4) +
91 					(c + 10 - (islower((unsigned char) c) ? 'a' : 'A'));
92 				cp++;
93 				continue;
94 			}
95 			break;
96 		}
97 		if (*cp == '.')
98 		{
99 			/*
100 			 * Internet format: a.b.c.d a.b.c	(with c treated as 16-bits)
101 			 * a.b	   (with b treated as 24 bits)
102 			 */
103 			if (pp >= parts + 3 || val > 0xff)
104 				return 0;
105 			*pp++ = val, cp++;
106 		}
107 		else
108 			break;
109 	}
110 
111 	/*
112 	 * Check for trailing junk.
113 	 */
114 	while (*cp)
115 		if (!isspace((unsigned char) *cp++))
116 			return 0;
117 
118 	/*
119 	 * Concoct the address according to the number of parts specified.
120 	 */
121 	n = pp - parts + 1;
122 	switch (n)
123 	{
124 
125 		case 1:					/* a -- 32 bits */
126 			break;
127 
128 		case 2:					/* a.b -- 8.24 bits */
129 			if (val > 0xffffff)
130 				return 0;
131 			val |= parts[0] << 24;
132 			break;
133 
134 		case 3:					/* a.b.c -- 8.8.16 bits */
135 			if (val > 0xffff)
136 				return 0;
137 			val |= (parts[0] << 24) | (parts[1] << 16);
138 			break;
139 
140 		case 4:					/* a.b.c.d -- 8.8.8.8 bits */
141 			if (val > 0xff)
142 				return 0;
143 			val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
144 			break;
145 	}
146 	if (addr)
147 		addr->s_addr = pg_hton32(val);
148 	return 1;
149 }
150