Constructing an ECPublic Key in Java from Java Card

Question

However in the answer it isn't explained how to extract x and y - how can I do this?

LozCodes · Accepted Answer · 2022-05-05T09:03:17.017

0

The 'w' value is made up of the x and y values.

The first byte should be either 04, 02 or 03 - which indicates if it is uncompressed or compressed. The last two bytes are status bytes, e.g. 90 00.

The remaining bytes are the x, then y value, which are both the same length

edited May 05 '22 at 09:03

answered May 03 '22 at 13:22

LozCodes

I miss the grouping information: x and y are supposed to have the same length. – guidot May 04 '22 at 21:05
Yes they are - let me edit my answer to include that – LozCodes May 05 '22 at 09:03

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