java - Generating ECDSA public key at host side from W parameter -


i want send public key of private-public key pair (ecdsa) generated in applet host application/terminal.

in rsa send modulus , exponent , generate public key @ host side.

in ecdsa read link can same if take w parameter bytes outside card click here: stackoverflow answer: encode public key on java

i have w bytes card now. can suggest how create public key this?

i wrote method convert ec public key java.security.interfaces.ecpublickey key object. use bouncy castle provider (bcprov-ext-jdk16-1.46.jar). can download latest version here.

/**  * method converts ec public key (ecpublickey#getw()) ecpublickey  * @param cardpublickey w  * @param curvename (for example "p-224")  * @return java.security.interfaces.ecpublickey  */ public ecpublickey ucpublickeytopublickey(byte[] cardpublickey, string curvename) {     //for example curvename = "p-224";     java.security.interfaces.ecpublickey ecpublickey = null; // java.security.interfaces.ecpublickey     java.security.keyfactory kf = null;      org.bouncycastle.jce.spec.ecnamedcurveparameterspec ecnamedcurveparameterspec = ecnamedcurvetable.getparameterspec(curvename);     org.bouncycastle.math.ec.eccurve curve = ecnamedcurveparameterspec.getcurve();     java.security.spec.ellipticcurve ellipticcurve = ec5util.convertcurve(curve, ecnamedcurveparameterspec.getseed());     java.security.spec.ecpoint ecpoint = ecpointutil.decodepoint(ellipticcurve, cardpublickey);     java.security.spec.ecparameterspec ecparameterspec = ec5util.convertspec(ellipticcurve, ecnamedcurveparameterspec);     java.security.spec.ecpublickeyspec publickeyspec = new java.security.spec.ecpublickeyspec(ecpoint, ecparameterspec);      try {         kf = java.security.keyfactory.getinstance("ec", "bc");     } catch (exception e) {         system.out.println("caught exception kf : " + e.tostring());     }      try {         ecpublickey = (ecpublickey) kf.generatepublic(publickeyspec);     } catch (exception e) {         system.out.println("caught exception public key: " + e.tostring());     }      return ecpublickey; }

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