example for RS256 openssl

[HenryNe]

An example with RS256 with encode and decode.
Keys are created by openssl and inline to make the example complete as single file.

openssl genrsa -out private.key 1024
openssl rsa -in private.key -pubout > pubkey.key

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[googlebot]

Thanks for your pull request. It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

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Once you've signed, please reply here (e.g. I signed it!) and we'll verify. Thanks.

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[HenryNe]

I signed it!

[googlebot]

CLAs look good, thanks!

[robertdimarco]

Neat!

[serroba]

pardon my ignorance. I would have thought that we should encode with the public key and decode with the private one.

[HenryNe]

You are wrong.
encode with private, so only you can sign the data.
JWT with public key is for checking signature, not for hiding information.
Information is base64 coded. See red header and payload on https://jwt.io/

[serroba]

Thanks for the explanation. Appreciated

[gbharath5182]

Hi, I am having the key like below
{
"keys":
[{"kty":"RSA",
"kid":"",
"use":"sig",
"n":"",
"e":"AQAB",
"x5c":[""],
"x5t":""}]}
Need assistance in verifying the signature using Firbase.JWT library in php.