openssl dgst <option>:

gost-mac          md4               md5               md_gost94
ripemd160         sha               sha1              sha224
sha256            sha384            sha512            streebog256
streebog512       whirlpool


-sign file        sign digest using private key in file
-verify file      verify a signature using public key in file
-signature file   signature to verify
-out filename     output to filename rather than stdout


// 签名
openssl dgst -sha256 -sign private.pem -out out.bin testfile
// 验证
openssl dgst -sha256 -verify public.pem -signature out.bin testfile

// 从p12文件中取出私钥
openssl pkcs12 -nodes -nocerts -in Mocca.pfx -out private.pem -passin pass:""