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openssl_x509_parse

(PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)

openssl_x509_parseX509 証明書をパースし、配列として情報を返す

説明

openssl_x509_parse(OpenSSLCertificate|string $certificate, bool $short_names = true): array|false

openssl_x509_parse() は、指定した certificate に関する情報を返します。この情報には 題名、発行者名、目的、発効日および有効期限等が含まれます。

パラメータ

certificate

X509証明書。正しい値の一覧は キー/証明書パラメータ を参照ください。

short_names

short_names は、配列中でのデータの添字付けの 方法を設定します。short_namestrue の場合 (デフォルト)、フィールドは短縮型で添字が付けられます。そうでない場合、 長い名前が使用されます。例えば、CN は commonName の短縮型です。

戻り値

返されるデータの構造については(わざと)まだ文書化していません。 これは、今後もデータの構造が変更される可能性があるためです。

変更履歴

バージョン 説明
8.0.0 certificate は、 OpenSSLCertificate クラスのインスタンスを受け入れるようになりました。 これより前のバージョンでは、 OpenSSL X.509 型のリソースを受け入れていました。
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User Contributed Notes 7 notes

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8
nathanael at dihedral dot de
18 years ago
When dealing with the purposes of a x509 crt file
the output of openssl_x509_parse gives an array with following for the purposes:
each new array ([purposes][1], [purposes][2] for example) is a new purpose check
I compared this output with the output of the command
# openssl x509 -purpose -in <x509crt_file>
the result i got was that
[purposes][x][2] quite obviously is the name of the purpose checked
[purposes][x][1] corresponds to the tested purpose (as named in [purposes][x][2]) acting as CA
[purposes][x][0] corresponds to the general availability of the purpose

[purposes] => Array
(
[1] => Array
(
[0] => 1
[1] => 1
[2] => sslclient
)

[2] => Array
(
[0] => 1
[1] => 1
[2] => sslserver
)

[3] => Array
(
[0] => 1
[1] => 1
[2] => nssslserver
)

[4] => Array
(
[0] => 1
[1] => 1
[2] => smimesign
)

[5] => Array
(
[0] => 1
[1] => 1
[2] => smimeencrypt
)

[6] => Array
(
[0] => 1
[1] => 1
[2] => crlsign
)

[7] => Array
(
[0] => 1
[1] => 1
[2] => any
)

[8] => Array
(
[0] => 1
[1] => 1
[2] => ocsphelper
)

)
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3
maarten at xolphin dot nl
19 years ago
At this time very useful X509 oids (like streetAddress, postalCode and others) are missing. You can find a list of them at http://www.alvestrand.no/objectid/2.5.4.html, I hope they get included to openssl-x509-parse soon.

Until then you can get these oids anyway like this:

<?
function getOID($OID, $ssl)
{
preg_match('/\/' . $OID . '=([^\/]+)/', $ssl, $matches);
return $matches[1];
}

$cert = file_get_contents('test.crt');
$ssl = openssl_x509_parse($cert);
$Address = getOID('2.5.4.9', $ssl['name']);
$ZipCode = getOID('2.5.4.17', $ssl['name']);
$Postbox = getOID('2.5.4.18', $ssl['name']);
?>

The parseCert function from the Horde framework can be usefull for this too.
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1
Stilez
8 years ago
The valid from/to info is returned twice, in two different formats. They can be converted to normal datetime objects like this:

$x509_data = openssl_x509_parse($cert);
date_create_from_format('ymdHise', $x509_data['validFrom'])->format('c');
date_create( '@' . $x509_data['validFrom_time_t'])->format('c');
/* these give the same result */

To get a human-readable format directly (or any other formatted string) instead of a datetime object, use this:

date_create_from_format('ymdHise', $x509_data['validFrom'])->format('c');
or
date_create( '@' . $x509_data['validFrom_time_t'])->format('c');

The same applies to validTo and validTo_time_t
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2
smgallo at buffalo dot edu
20 years ago
The identifier for the email portion of certificates in the name and subject array have changed since PHP4. In PHP 4.3.0 the following array was returned (displayed my print_r())

[name] => /O=Grid/O=Globus/O=CCR Grid Portal/OU=Portal User/CN=Test User/Email=test@nospam.buffalo.edu
[subject] => Array
(
[O] => Grid/O=Globus/O=CCR Grid Portal
[OU] => Portal User
[CN] => Test User
[Email] => test@nospam.buffalo.edu
...

The result in PHP5 is (note Email -> emailAddress):

[name] => /O=Grid/O=Globus/O=CCR Grid Portal/OU=Portal User/CN=Test User/emailAddress=test@nospam.buffalo.edu
[subject] => Array
(
[O] => Grid/O=Globus/O=CCR Grid Portal
[OU] => Portal User
[CN] => Test User
[emailAddress] => test@nospam.buffalo.edu
...

Of course, the manual DOES say this could happen. :)
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1
s dot stok at rollerscapes dot net
14 years ago
Alternative subjects can read as extensions.

[extensions]
[subjectAltName] => DNS:*.cacert.org, DNS:cacert.org, DNS:*.cacert.net, DNS:cacert.net, DNS:*.cacert.com, DNS:cacert.com
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2
koukopoulos at gmail dot com
16 years ago
Re: the previous note: support for the x509v3 extensions was added in PHP 5.2. Also in PHP5 prior to 5.2.4 the values of the x509v3 extensions were not decoded and were returned in the DER binary representation. Therefore in order to read the contents of the v3 extensions you have to parse the relevant ASN.1 structures yourself.

For example if one needs to read an IA5STRING value in a private extension with the OID 1.3.6.1.4.1.7782.3.3 one can do :

<?php

/* parse a DER encoded representation
of a IA5STRING of length < 127 */
function asn1der_ia5string($str)
{
$len=strlen($str)-2;
if (
$len < 0 && $len > 127) {
return
false;
}

/* check tag and len */
if (22 != (ord($str[$pos++]) & 0x1f) &&
ord($str[$pos++]) != $len) {
/* not a valid DER encoding of an IA5STRING */
return false;
}

return
substr($str, 2, $len);
}
$cert = openssl_x509_parse($pemcert);
print (
asn1der_ia5string($cert['extensions']['1.3.6.1.4.1.7782.3.3'])); // prints decoded ascii string

?>

In newer versions (>5.2.3) the extensions are returned in a 'readable format'. For example:

<?php print_r(openssl_x509_parse(...)); ?>
will result in
<?
Array
(
[name] => /C=GR/O=SOMETHING/CN=ME/
...
[extensions] => Array
(
[basicConstraints] => CA:FALSE
[keyUsage] => Digital Signature, Non Repudiation, Key Encipherment
[extendedKeyUsage] => E-mail Protection, TLS Web Client Authentication
[nsCertType] => SSL Client, S/MIME
....
?>
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-4
zioproto at gmail dot com
16 years ago
To read an extension from a X.509 certificate, you can proceed like this if you know the OID

//Read the certificate from file
$cert = file_get_contents('test.crt');
$ssl = openssl_x509_parse($cert);

$ext_value = $ssl['extensions']['1.2.3.4.5.6'];
echo $ext_value

--------------------------------

Because the $ssl array is not documented, you can easily see its contents like this:

//To print out all the array!
print_r(array_values($ssl));
print_r(array_keys($ssl));
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