|
1
|
|
|
<?php |
|
2
|
|
|
declare(strict_types=1); |
|
3
|
|
|
|
|
4
|
|
|
namespace Mdanter\Ecc\Serializer\Point; |
|
5
|
|
|
|
|
6
|
|
|
use Mdanter\Ecc\Math\GmpMathInterface; |
|
7
|
|
|
use Mdanter\Ecc\Primitives\CurveFpInterface; |
|
8
|
|
|
use Mdanter\Ecc\Primitives\PointInterface; |
|
9
|
|
|
use Mdanter\Ecc\Serializer\Util\CurveOidMapper; |
|
10
|
|
|
|
|
11
|
|
|
class CompressedPointSerializer implements PointSerializerInterface |
|
12
|
|
|
{ |
|
13
|
|
|
/** |
|
14
|
|
|
* @var GmpMathInterface |
|
15
|
|
|
*/ |
|
16
|
|
|
private $adapter; |
|
17
|
|
|
|
|
18
|
|
|
/** |
|
19
|
|
|
* @var \Mdanter\Ecc\Math\NumberTheory |
|
20
|
|
|
*/ |
|
21
|
|
|
private $theory; |
|
22
|
|
|
|
|
23
|
|
|
/** |
|
24
|
|
|
* CompressedPointSerializer constructor. |
|
25
|
|
|
* @param GmpMathInterface $adapter |
|
26
|
|
|
*/ |
|
27
|
|
|
public function __construct(GmpMathInterface $adapter) |
|
28
|
|
|
{ |
|
29
|
|
|
$this->adapter = $adapter; |
|
30
|
|
|
$this->theory = $adapter->getNumberTheory(); |
|
31
|
|
|
} |
|
32
|
|
|
|
|
33
|
|
|
/** |
|
34
|
|
|
* @param PointInterface $point |
|
35
|
|
|
* @return string |
|
36
|
|
|
*/ |
|
37
|
|
|
public function getPrefix(PointInterface $point): string |
|
38
|
|
|
{ |
|
39
|
|
|
if ($this->adapter->equals($this->adapter->mod($point->getY(), gmp_init(2, 10)), gmp_init(0))) { |
|
|
|
|
|
|
40
|
|
|
return '02'; |
|
41
|
|
|
} else { |
|
42
|
|
|
return '03'; |
|
43
|
|
|
} |
|
44
|
|
|
} |
|
45
|
|
|
|
|
46
|
|
|
/** |
|
47
|
|
|
* @param PointInterface $point |
|
48
|
|
|
* @return string |
|
49
|
|
|
*/ |
|
50
|
|
|
public function serialize(PointInterface $point): string |
|
51
|
|
|
{ |
|
52
|
|
|
$length = CurveOidMapper::getByteSize($point->getCurve()) * 2; |
|
53
|
|
|
|
|
54
|
|
|
$hexString = $this->getPrefix($point); |
|
55
|
|
|
$hexString .= str_pad(gmp_strval($point->getX(), 16), $length, '0', STR_PAD_LEFT); |
|
56
|
|
|
|
|
57
|
|
|
return $hexString; |
|
58
|
|
|
} |
|
59
|
|
|
|
|
60
|
|
|
/** |
|
61
|
|
|
* @param CurveFpInterface $curve |
|
62
|
|
|
* @param string $data - hex serialized compressed point |
|
63
|
|
|
* @return PointInterface |
|
64
|
|
|
*/ |
|
65
|
|
|
public function unserialize(CurveFpInterface $curve, string $data): PointInterface |
|
66
|
|
|
{ |
|
67
|
|
|
$prefix = substr($data, 0, 2); |
|
68
|
|
|
if ($prefix !== '03' && $prefix !== '02') { |
|
69
|
|
|
throw new \InvalidArgumentException('Invalid data: only compressed keys are supported.'); |
|
70
|
|
|
} |
|
71
|
|
|
|
|
72
|
|
|
$x = gmp_init(substr($data, 2), 16); |
|
73
|
|
|
$y = $curve->recoverYfromX($prefix === '03', $x); |
|
|
|
|
|
|
74
|
|
|
|
|
75
|
|
|
return $curve->getPoint($x, $y); |
|
|
|
|
|
|
76
|
|
|
} |
|
77
|
|
|
} |
|
78
|
|
|
|
shanecurran /
phpecc
Loading history...