1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
<?php
declare(strict_types=1);
class IpUtil
{
public static function rangeToCidr(int $start, int $end): string
{
$value = $end - $start;
if (!self::isAllOnes($value))
return 'NOT SUBNET: ' . long2ip($start) . '-' . long2ip($end);
$ones = self::bitLength($value);
return long2ip($start) . '/' . (32 - $ones);
}
public static function isValidSubnetRange(int $start, int $end): bool
{
return self::isAllOnes($end - $start);
}
/**
* Return number of bits required to represent
* this number.
* !! Assumes given number is 2^n - 1 !!
*/
private static function bitLength(int $value): int
{
// This is log(value) / log(2)
// It should actually be $value + 1, but floating point errors
// start to happen either way at higher values, so with
// the round() thrown in, it doesn't matter...
return (int)round(log($value) / 0.69314718055995);
}
/**
* Is the given number just ones if converted to
* binary (ignoring leading zeros)?
*/
private static function isAllOnes(int $value): bool
{
return ($value & ($value + 1)) === 0;
}
/**
* Parse network range in CIDR notion, return
* ['start' => (int), 'end' => (int)] representing
* the according start and end addresses as integer
* values. Returns false on malformed input.
*
* @param string $cidr 192.168.101/24, 1.2.3.4/16, ...
* @return array{start: int, end: int}|null start and end address, false on error
*/
public static function parseCidr(string $cidr): ?array
{
$parts = explode('/', $cidr);
if (count($parts) !== 2) {
$ip = ip2long($cidr);
if ($ip === false)
return null;
return ['start' => $ip, 'end' => $ip];
}
$ip = $parts[0];
$bits = $parts[1];
if (!is_numeric($bits) || $bits < 0 || $bits > 32)
return null;
$dots = substr_count($ip, '.');
if ($dots < 3) {
$ip .= str_repeat('.0', 3 - $dots);
}
$ip = ip2long($ip);
if ($ip === false)
return null;
$bits = (int)((2 ** (32 - $bits)) - 1);
return ['start' => $ip & ~$bits, 'end' => $ip | $bits];
}
/**
* Normalizes an IP address to the canonical form.
* This supports all numeric IPv4, IPv6 and IPv4-mapped IPv6 addresses.
* As well as odd formats like IPv4 with multiple octets collapsed into a single one.
* Returns null if the address is invalid.
*/
public static function normalizeIp(string $ip): ?string
{
$ip = trim($ip);
if ($ip === '')
return null;
// Check simple case first
$addr = @inet_pton($ip);
if ($addr !== false) {
$ret = inet_ntop($addr);
if (substr($ret, 0, 7) === '::ffff:')
return substr($ret, 7);
return $ret;
}
if (strpos($ip, ':') !== false)
return null;
// IPv4 handling
// Support octal, hex and shorthand notations
$parts = explode('.', $ip);
$numParts = count($parts);
if ($numParts > 4)
return null;
$values = [];
foreach ($parts as $part) {
$part = trim($part);
if ($part === '')
return null;
// Check for hex (0x...)
if (strncasecmp($part, '0x', 2) === 0) {
if (!ctype_xdigit(substr($part, 2)))
return null;
$values[] = hexdec($part);
} elseif ($part[0] === '0' && strlen($part) > 1) {
// Octal (starts with 0, but not just 0)
if (!preg_match('/^[0-7]+$/', $part))
return null;
$values[] = octdec($part);
} else {
// Decimal
if (!preg_match('/^[0-9]+$/', $part))
return null;
$values[] = (int)$part;
}
}
if (empty($values))
return null;
// Validate values and handle shorthands
// Rules:
// 1 part: a (32 bits)
// 2 parts: a.b (a: 8 bits, b: 24 bits)
// 3 parts: a.b.c (a: 8 bits, b: 8 bits, c: 16 bits)
// 4 parts: a.b.c.d (a: 8 bits, b: 8 bits, c: 8 bits, d: 8 bits)
$ipv4int = 0;
for ($i = 0; $i < $numParts; $i++) {
$val = $values[$i];
if ($i === $numParts - 1) {
// Last part
$max = (2 ** (8 * (4 - $i))) - 1;
if ($val < 0 || $val > $max)
return null;
$ipv4int = ($ipv4int << (8 * (4 - $i))) | (int)$val;
} else {
if ($val < 0 || $val > 255)
return null;
$ipv4int = ($ipv4int << 8) | (int)$val;
}
}
return long2ip($ipv4int);
}
/**
* Check if given string is a valid IP address.
* Supports all kinds of IP address formats that PHP supports,
* including IPv6, IPv4-mapped IPv6, IPv4-in-IPv6, etc.
*/
public static function isValidIp(string $ip): bool
{
return self::normalizeIp($ip) !== null;
}
}
|
