ECDH- NID_X9_62_prime256v1 - EVP_RAND_instantiate()

[Damodhar Boddukuri via openssl-users <openssl-users@xxxxxxxxxxx>]

Hi,

 

I am implementing ECDH- Group19 (NID_X9_62_prime256v1). I followed the below sequence.

1. ecdh_group = EC_GROUP_new_by_curve_name(NID_X9_62_prime256v1); // NID_X9_62_prime256v1 or  NID_secp256k1
2. ecdh_keys = EC_KEY_new();
3. ret = EC_KEY_set_group(ecdh_keys, ecdh_group);
4. ret = EC_KEY_generate_key(ecdh_keys);

At 4^th step, function EVP_RAND_instantiate()  returning ‘1’ for the 1^st time. Then 2^nd time onward it’s returning ‘0’. Because of this reason 4^th step is failing.

 

Could you please let me know the possible reasons for it.

 

Thanks & Regards,

Damodhar.

 

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