function oid2hex($n)
{
if (is_int($n)) {
$oidHex = $n > 127 ? dec2hex(128 | $n / 128) . dec2hex($n % 128) : dec2hex($n);
} else {
$oidHex = '';
$oid = explode('.', $n);
$n1 = 40 * $oid[0] + $oid[1];
$oidHex .= dec2hex($n1);
unset($oid[0], $oid[1]);
foreach ($oid as $n) {
$oidHex .= oid2hex((int) $n);
}
}
return $oidHex;
}
protected static function packVar($var, $type = null, $varInHex = false)
{
/**
* @link http://en.wikipedia.org/wiki/Basic_encoding_rules
P/C is the primitive/constructed bit, it specifies if the value is primitive like an INTEGER or constructed which means, it again holds TLV values like a SET. If the bit is "on" (value = 1), it indicates a constructed value.
Name P/C dec hex
EOC (End-of-Content) P 0 0x00
BOOLEAN P 1 0x01
INTEGER P 2 0x02
BIT STRING P/C 3 0x03
OCTET STRING P/C 4 0x04
NULL P 5 0x05
OBJECT IDENTIFIER P 6 0x06
Object Descriptor P 7 0x07
EXTERNAL C 8 0x08
REAL (float) P 9 0x09
ENUMERATED P 10 0x0A
EMBEDDED PDV C 11 0x0B
UTF8String P/C 12 0x0C
RELATIVE-OID P 13 0x0D
SEQUENCE and SEQUENCE OF C 16 0x10
SET and SET OF C 17 0x11
NumericString P/C 18 0x12
PrintableString P/C 19 0x13
T61String P/C 20 0x14
VideotexString P/C 21 0x15
IA5String P/C 22 0x16
UTCTime P/C 23 0x17
GeneralizedTime P/C 24 0x18
GraphicString P/C 25 0x19
VisibleString P/C 26 0x1A
GeneralString P/C 27 0x1B
UniversalString P/C 28 0x1C
CHARACTER STRING P/C 29 0x1D
BMPString P/C 30 0x1E
IpAddress 40
Counter (Counter32 in SNMPv2) 41
Gauge (Gauge32 in SNMPv 2) 42
TimeTicks 43
Opaque 44
NsapAddress 45
Counter64 (available only in SNMPv2) 46
Uinteger32 (available only in SNMPv2) 47
*/
$type2hex = array('s' => '04', 'i' => '02', 'oid' => '06', 'o' => '43');
if ($type[0] == 'x') {
$typeHex = $type[1] . $type[2];
$type = 'x';
} else {
$type = $type == 'oid' ? $type : substr($type, 0, 1);
$type = $type ? $type : substr(gettype($var), 0, 1);
$typeHex = $type2hex[$type];
}
$varHex = '';
if ($type == 'i') {
$varHex = $varInHex ? $var : dec2hex($var);
}
if ($type == 's') {
$varHex = $varInHex ? $var : str2hex($var);
}
if ($type == 'o') {
$varHex = $varInHex ? $var : dec2hex($var);
}
if ($type == 'x') {
$varHex = $varInHex ? $var : $var;
}
// if object, we pass hex data in $var
if ($type == 'oid') {
$varHex = $varInHex ? $var : oid2hex($var);
}
$bodyPack = pack('H*', $varHex);
$headPack = pack('H*', $typeHex . self::hexlen($bodyPack));
return $headPack . $bodyPack;
}
