TL;DR It's not a bug, it's a feature! Hi, you can generate explicit parameters for that curve by: `openssl ecparam -name Oakley-EC2N-3 -param_enc explicit` the command in your case was failing because by default it tries to generate a named_curve ASN1 encoding, which fails because there is no OID associated with Oakley-EC2N-3. You can have a look at https://github.com/openssl/openssl/issues/5723 and https://github.com/openssl/openssl/pull/5725 that fixes it. This change has been included in the 1.0.2 branch since 1.0.2p; in 1.0.2o your command will silently fail as the generated PEM file would be invalid. Best regards, Nicola Tuveri On Wed, 20 Mar 2019 at 19:29, shiva kumar <shivakumar2696@xxxxxxxxx> wrote: > > Hi, > When I run openssl ecparam on elliptic curve Oakley-EC2N-3, > Oakley-EC2N-4 on openssl 1.0.2r version, > I am getting the following error, can anyone please help me why i am getting this error. > > # openssl ecparam -out Oakley-EC2N-3_102r.pem -name Oakley-EC2N-3 > unable to write elliptic curve parameters > 2063867464:error:100BF079:elliptic curve routines:i2d_ECPKParameters:i2d ecpkparameters failure:ec_asn1.c:1011: > 2063867464:error:100BF079:elliptic curve routines:i2d_ECPKParameters:i2d ecpkparameters failure:ec_asn1.c:1011: > > unable to write elliptic curve parameters > 2063867464:error:100BF079:elliptic curve routines:i2d_ECPKParameters:i2d ecpkparameters failure:ec_asn1.c:1011: > 2063867464:error:100BF079:elliptic curve routines:i2d_ECPKParameters:i2d ecpkparameters failure:ec_asn1.c:1011: > > Thanks and Regards > shivakumar
