Constructed OCTET_STRING - a real-life example about asn1 HOT 5 CLOSED

Hi!

Thanks for the files that helped me to reproduce the problem. Great that you managed to fix a workaround as well! :)

It appears that constructed strings are a thing in BER encoding. I added rudimentary support for this in php72 branch. That's a development branch that will be merged in the near future. It does require PHP 7.2 however. Can you checkout and try it?

from asn1.

Thanks for your quick answer! Great that you have support for this in the php72 branch. Unfortunately I might have to support PHP 7.1 also, but I will have a look at the branch!

EDIT: In my PHP 7.2 version I can use your php72 branch successfully! What about backporting the ConstructedString into master? How much effort would this be?

from asn1.

Hi!

Good to hear. I'll add the functionality to old master. I've created a php70 branch and backported what i've done so far. Feel free to try it out.
I'll add a couple of features before publishing a tag though. Maybe tomorrow.

from asn1.

I've pushed some changes to php70 branch. Given your example data, here's how one could extract the payload as a concatenated string:

$data = file_get_contents(__DIR__ . '/constructed-octet-string.der');
$content_info = Element::fromDER($data)->asUnspecified()->asSequence();
$signed_data = $content_info->at(1)->asTagged()->asExplicit()->asSequence();
$encapsulated = $signed_data->at(2)->asSequence();
$content = $encapsulated->at(1)->asTagged()->asExplicit()->asConstructedString();
echo $content->string() . "\n";

Do you think this would be sufficient?

from asn1.

Thank you! I'm using branch php70 now. I ended up as this:

$encapContentInfo = $signedData->at(2)->asSequence();
$content = $encapContentInfo->getTagged(0)->asExplicit()->asElement();
if ($content instanceof Stringable) { return $content->string(); }

from asn1.