## Common OpenSSL Commands with Keys and Certificates

[SSL Info](https://www.digitalocean.com/community/tutorials/openssl-essentials-working-with-ssl-certificates-private-keys-and-csrs)

### Generate RSA private key with certificate in a single command
    openssl req -x509 -newkey rsa:4096 -sha256 -keyout example.key -out example.crt -subj "/CN=example.com" -days 3650 -passout pass:foobar
    
### Generate Certificate Signing Request (CSR) from private key with passphrase
    
    openssl x509 -x509toreq -in example.crt -out example.csr -signkey example.key -passin pass:foobar

#### Generate RSA private key (2048 bit)

    openssl genrsa -out private.pem 2048

#### Generate a Certificate Signing Request (CSR)

    openssl req -sha256 -new -key private.pem -out csr.pem

#### Generate RSA private key (2048 bit) and a Certificate Signing Request (CSR) with a single command

    openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out server.csr

#### Convert private key to PEM format

    openssl rsa -in server.key -outform PEM -out server.pem

#### Generate a self-signed certificate that is valid for a year with sha256 hash

    openssl x509 -req -sha256 -days 365 -in csr.pem -signkey private.pem -out certificate.pem

#### View details of a RSA private key

    openssl rsa -in private.pem -text -noout

#### View details of a CSR

    openssl req -in csr.pem -text -noout

#### View details of a Certificate

    openssl x509 -in certificate.pem -text -noout

#### View details of a Certificate in DER format

    openssl x509 -inform der -in certificate.cer -text -noout

#### Convert a DER file (.crt .cer .der) to PEM

    openssl x509 -inform der -in certificate.cer -out certificate.pem

#### Convert a PEM file to DER

    openssl x509 -outform der -in certificate.pem -out certificate.cer