AMCL JS create rsa_public_key from ASN1 formatted X.509 public key. about core HOT 7 CLOSED

Yes, that should be possible. In rsa.js there would be a need to provide a new function

set_rsa_public_key = function(ctx,n,e)

similar to the existing

rsa_public_key = function(ctx)

Where the public key n is provided as a byte array extracted from an X.509 cert, and e=65537. Then use the ff.js function

FF.fromBytes = function(x, b)

to copy n into the public key structure.

(Note: we would regard X.509 cert processing as outside of the remit of this library)

from core.

Ok. Thank you!

Pascal

from core.

I am not sure, if that is wished, but maybe it could be useful to have getter and setter for the objects rsa_public_key and rsa_private_key. In the following is a suggestion how it could be done:

ctx.rsa_public_key.set(n,e);
ctx.rsa_public_key.set_e(e);
ctx.rsa_public_key.set_n(n);

ctx.rsa_public_key.get_instance(n,e);

Whereby the get_instance method creates a new rsa_public_key object and set the properties n and e.
It is also possible to do respectively also getter and setter for the rsa_private_key and a get_instance method for setting the attributes manually.
What do you think about the idea?

Maybe that would be better as creating a "new" rsa_public_key object and it is possible to use the existing structure.
If you want I can create a Pull Request, depends on if you think that could be useful for the library.

from core.

Yes, OK, that sounds like a good plan. Make sure and test it on a real X.509 public key!

Mike

from core.

It seems that it is possible to store a public key in that structure.
I used [1] as asn1 parser and stored the bytes directly into the rsa_public_key structure with the get_instance method.

Pull Request is on the way - without the asn1 parser, only the rsa key data strucutres.

Anyway I have a question regarding the data in the array which I get back from the FF data structure.
Which representation have the content of the following array?

[ 190,  66, 142, 139,  46, 151, 187, 158, 173, 174, 147, 123, ... ]

is the the 190 (from index 0) in hex or in uint or something else? I am a bit confused about the representation and wanted to know which representation are used here.

Thank you in advance!

[1] https://git.coolaj86.com/coolaj86/asn1-parser.js

from core.

Those are just unsigned byte values, in decimal

from core.

Thank you.

from core.