Openssl genrsa命令

openssl  genrsa [-out filename] [-passout arg] [-f4] [-3] [-rand file(s)] [-engine id] [numbits] [-des] [-des3] [-idea]

usage: genrsa [args] [numbits]
 -des            encrypt the generated key with DES in cbc mode
 -des3           encrypt the generated key with DES in ede cbc mode (168 bit key)
 -idea           encrypt the generated key with IDEA in cbc mode
 -seed
                 encrypt PEM output with cbc seed
 -aes128, -aes192, -aes256
                 encrypt PEM output with cbc aes
 -camellia128, -camellia192, -camellia256
                 encrypt PEM output with cbc camellia
 -out file       output the key to ‘file
 -passout arg    output file pass phrase source
 -f4             use F4 (0x10001) for the E value
 -3              use 3 for the E value
 -engine e       use engine e, possibly a hardware device.
 -rand file:file:...
                 load the file (or the files in the directory) into
                 the random number generator

openssl genrsa -des -passout pass:"1234546" -out prikey.pem 1024

openssl rsa -in prikey.pem -out pubkey.pem -pubout

参考：http://blog.csdn.net/fym0121/article/details/7987512