openssl ec [-inform PEM|DER] [-outform PEM|DER] [-in filename] [-out filename] [-passin arg] [-passout arg] [-text] [-noout] [-param_out] [-conv_form arg] [-pubin] [-pubout] [-param_enc arg] [-engine id] [-des] [-des3] [-idea]

-inform arg     input format - DER or PEM
 -outform arg    output format - DER or PEM
 -in arg         input file
 -passin arg     input file pass phrase source
 -out arg        output file
 -passout arg    output file pass phrase source
 -engine e       use engine e, possibly a hardware device.
 -des            encrypt PEM output, instead of 'des' every other 
                 cipher supported by OpenSSL can be used
 -text           print the key
 -noout          don't print key out
 -param_out      print the elliptic curve parameters
 -conv_form arg  specifies the point conversion form 
                 possible values: compressed
                                  uncompressed (default)
                                   hybrid
 -param_enc arg  specifies the way the ec parameters are encoded
                 in the asn1 der encoding
                 possible values: named_curve (default)
                                  explicit

1、生成EC私钥

openssl ecparam -genkey -name prime256v1 -param_enc explicit -outform pem -out ec_prikey.pem

2、对私钥进行口令保护

openssl ec -in ec_prikey.pem -des -out ec_prikey.pem

openssl ec -in ec_prikey.pem -des -passout pass:"123456" -out ec_prikey.pem

3、从私钥提取公钥

openssl ec -in ec_prikey.pem -pubout -out ec_pubkey.pem

4、查看私钥信息

openssl ec -in ec_prikey.pem -passin pass:"123456" -text

5、查看公钥信息

openssl ec -in ec_pubkey.pem -pubin -text

6、pem为der

openssl ec -in ec_prikey.pem -outform der -out ec_prikey.der