v4 UUID를 생성하는 PHP 함수

v4 UUID를 생성하는 PHP 함수

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그래서 나는 파고 들었고 PHP에서 유효한 v4 UUID를 생성하는 함수를 함께 모 으려고 노력했습니다. 이것은 내가 올 수 있었던 가장 가까운 것입니다. 16 진수, 10 진수, 이진, PHP의 비트 연산자 등에 대한 나의 지식은 거의 존재하지 않습니다. 이 함수는 한 영역까지 유효한 v4 UUID를 생성합니다. v4 UUID는 다음과 같은 형식이어야합니다.

XXXXXXXX-xxxx- 4 xxx- Y의 XXX-xxxxxxxxxxxx 여기서

여기서 y 는 8, 9, A 또는 B입니다.이 기능은이를 준수하지 않아 기능이 실패하는 곳입니다.

나는이 분야에서 나보다 더 많은 지식을 가진 사람이 나에게 손을 빌려주고이 규칙을 준수하도록이 기능을 수정하도록 도울 수 있기를 바랐습니다.

기능은 다음과 같습니다.

<?php

function gen_uuid() {
 $uuid = array(
  'time_low'  => 0,
  'time_mid'  => 0,
  'time_hi'  => 0,
  'clock_seq_hi' => 0,
  'clock_seq_low' => 0,
  'node'   => array()
 );

 $uuid['time_low'] = mt_rand(0, 0xffff) + (mt_rand(0, 0xffff) << 16);
 $uuid['time_mid'] = mt_rand(0, 0xffff);
 $uuid['time_hi'] = (4 << 12) | (mt_rand(0, 0x1000));
 $uuid['clock_seq_hi'] = (1 << 7) | (mt_rand(0, 128));
 $uuid['clock_seq_low'] = mt_rand(0, 255);

 for ($i = 0; $i < 6; $i++) {
  $uuid['node'][$i] = mt_rand(0, 255);
 }

 $uuid = sprintf('%08x-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x',
  $uuid['time_low'],
  $uuid['time_mid'],
  $uuid['time_hi'],
  $uuid['clock_seq_hi'],
  $uuid['clock_seq_low'],
  $uuid['node'][0],
  $uuid['node'][1],
  $uuid['node'][2],
  $uuid['node'][3],
  $uuid['node'][4],
  $uuid['node'][5]
 );

 return $uuid;
}

?>

나를 도울 수있는 사람에게 감사합니다.

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Taken from this comment on the PHP manual, you could use this:

function gen_uuid() {
    return sprintf( '%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
        // 32 bits for "time_low"
        mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ),

        // 16 bits for "time_mid"
        mt_rand( 0, 0xffff ),

        // 16 bits for "time_hi_and_version",
        // four most significant bits holds version number 4
        mt_rand( 0, 0x0fff ) | 0x4000,

        // 16 bits, 8 bits for "clk_seq_hi_res",
        // 8 bits for "clk_seq_low",
        // two most significant bits holds zero and one for variant DCE1.1
        mt_rand( 0, 0x3fff ) | 0x8000,

        // 48 bits for "node"
        mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff ), mt_rand( 0, 0xffff )
    );
}

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Instead of breaking it down into individual fields, it's easier to generate a random block of data and change the individual byte positions. You should also use a better random number generator than mt_rand().

According to RFC 4122 - Section 4.4, you need to change these fields:

1. time_hi_and_version (bits 4-7 of 7th octet),
2. clock_seq_hi_and_reserved (bit 6 & 7 of 9th octet)

All of the other 122 bits should be sufficiently random.

The following approach generates 128 bits of random data using openssl_random_pseudo_bytes(), makes the permutations on the octets and then uses bin2hex() and vsprintf() to do the final formatting.

function guidv4($data)
{
    assert(strlen($data) == 16);

    $data[6] = chr(ord($data[6]) & 0x0f | 0x40); // set version to 0100
    $data[8] = chr(ord($data[8]) & 0x3f | 0x80); // set bits 6-7 to 10

    return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
}

echo guidv4(openssl_random_pseudo_bytes(16));

With PHP 7, generating random byte sequences is even simpler using random_bytes():

function guidv4($data = null)
{
    $data = $data ?? random_bytes(16);
    // ...
}

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Anyone using composer dependencies, you might want to consider this library: https://github.com/ramsey/uuid

It doesn't get any easier than this:

Uuid::uuid4();

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on unix systems, use the system kernel to generate a uuid for you.

file_get_contents('/proc/sys/kernel/random/uuid')

Credit Samveen on https://serverfault.com/a/529319/210994

Note!: Using this method to get a uuid does in fact exhaust the entropy pool, very quickly! I would avoid using this where it would be called frequently.

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In my search for a creating a v4 uuid, I came first to this page, then found this on http://php.net/manual/en/function.com-create-guid.php

function guidv4()
{
    if (function_exists('com_create_guid') === true)
        return trim(com_create_guid(), '{}');

    $data = openssl_random_pseudo_bytes(16);
    $data[6] = chr(ord($data[6]) & 0x0f | 0x40); // set version to 0100
    $data[8] = chr(ord($data[8]) & 0x3f | 0x80); // set bits 6-7 to 10
    return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
}

credit: pavel.volyntsev

Edit: to clarify, this function will always give you a v4 uuid (PHP >= 5.3.0).

When the com_create_guid function is available (usually only on Windows), it will use that and strip the curly braces.

If not present (Linux), it will fall back on this strong random openssl_random_pseudo_bytes function, it will then uses vsprintf to format it into v4 uuid.

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My answer is based on comment uniqid user comment but it uses openssl_random_pseudo_bytes function to generate random string instead of reading from /dev/urandom

function guid()
{
    $randomString = openssl_random_pseudo_bytes(16);
    $time_low = bin2hex(substr($randomString, 0, 4));
    $time_mid = bin2hex(substr($randomString, 4, 2));
    $time_hi_and_version = bin2hex(substr($randomString, 6, 2));
    $clock_seq_hi_and_reserved = bin2hex(substr($randomString, 8, 2));
    $node = bin2hex(substr($randomString, 10, 6));

    /**
     * Set the four most significant bits (bits 12 through 15) of the
     * time_hi_and_version field to the 4-bit version number from
     * Section 4.1.3.
     * @see http://tools.ietf.org/html/rfc4122#section-4.1.3
    */
    $time_hi_and_version = hexdec($time_hi_and_version);
    $time_hi_and_version = $time_hi_and_version >> 4;
    $time_hi_and_version = $time_hi_and_version | 0x4000;

    /**
     * Set the two most significant bits (bits 6 and 7) of the
     * clock_seq_hi_and_reserved to zero and one, respectively.
     */
    $clock_seq_hi_and_reserved = hexdec($clock_seq_hi_and_reserved);
    $clock_seq_hi_and_reserved = $clock_seq_hi_and_reserved >> 2;
    $clock_seq_hi_and_reserved = $clock_seq_hi_and_reserved | 0x8000;

    return sprintf('%08s-%04s-%04x-%04x-%012s', $time_low, $time_mid, $time_hi_and_version, $clock_seq_hi_and_reserved, $node);
} // guid

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If you use CakePHP you can use their method CakeText::uuid(); from the CakeText class to generate a RFC4122 uuid.

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Inspired by broofa's answer here.

preg_replace_callback('/[xy]/', function ($matches)
{
  return dechex('x' == $matches[0] ? mt_rand(0, 15) : (mt_rand(0, 15) & 0x3 | 0x8));
}
, 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx');

Or if unable to use anonymous functions.

preg_replace_callback('/[xy]/', create_function(
  '$matches',
  'return dechex("x" == $matches[0] ? mt_rand(0, 15) : (mt_rand(0, 15) & 0x3 | 0x8));'
)
, 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx');

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Having searched for the exact same thing and almost implementing a version of this myself, I thought it was worth mentioning that, if you're doing this within a WordPress framework, WP has its own super-handy function for exactly this:

$myUUID = wp_generate_uuid4();

You can read the description and the source here.

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A slight variation on Jack's answer to add support for PHP < 7:

// Get an RFC-4122 compliant globaly unique identifier
function get_guid() {
    $data = PHP_MAJOR_VERSION < 7 ? openssl_random_pseudo_bytes(16) : random_bytes(16);
    $data[6] = chr(ord($data[6]) & 0x0f | 0x40);    // Set version to 0100
    $data[8] = chr(ord($data[8]) & 0x3f | 0x80);    // Set bits 6-7 to 10
    return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
}

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From tom, on http://www.php.net/manual/en/function.uniqid.php

$r = unpack('v*', fread(fopen('/dev/random', 'r'),16));
$uuid = sprintf('%04x%04x-%04x-%04x-%04x-%04x%04x%04x',
    $r[1], $r[2], $r[3], $r[4] & 0x0fff | 0x4000,
    $r[5] & 0x3fff | 0x8000, $r[6], $r[7], $r[8])

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How about using mysql to generate the uuid for you?

$conn = new mysqli($servername, $username, $password, $dbname, $port);

$query = 'SELECT UUID()';
echo $conn->query($query)->fetch_row()[0];

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I'm sure there's a more elegant way to do the conversion from binary to decimal for the 4xxx and yxxx portions. But if you want to use openssl_random_pseudo_bytes as your crytographically secure number generator, this is what I use:

return sprintf('%s-%s-%04x-%04x-%s',
    bin2hex(openssl_random_pseudo_bytes(4)),
    bin2hex(openssl_random_pseudo_bytes(2)),
    hexdec(bin2hex(openssl_random_pseudo_bytes(2))) & 0x0fff | 0x4000,
    hexdec(bin2hex(openssl_random_pseudo_bytes(2))) & 0x3fff | 0x8000,
    bin2hex(openssl_random_pseudo_bytes(6))
    );

참고URL : https://stackoverflow.com/questions/2040240/php-function-to-generate-v4-uuid