OpenSSL generate multi cert

Generate many user certificates

the size of the key to generate in bits
Country Name (2 letter code) [ex. GB]
State or Province Name (full name)
Locality Name (eg, city)
Organization Name (eg, company)
many user's information*	User information deals with one user by the line. The line delimits by the comma and describes a organizational unit name, a common name, and the mail address. The comma(,) and the quotation mark(") cannot be used for a organizational unit name(empty is acceptable), a common name, and the mail address. It is possible to describe it up to 100 users at a time. It becomes for a fee more than 101 users.
CA's private key*	PEM format data is lines from '-----BEGIN' to '-----END'.
CA's certificate*	PEM format data is lines from '-----BEGIN' to '-----END'.

Generate many user certificates