OpenSSL commands

Posted on Thu 01 December 2016 in certificates

Generate a new private key and Certificate Signing Request

$ openssl req -out CSR.csr -new -newkey rsa:2048 -nodes -keyout privateKey.key

Generate a self-signed certificate

$ openssl req -x509 -sha256 -nodes -days 365 -newkey rsa:2048 -keyout privateKey.key -out certificate.crt

Generate a certificate signing request (CSR) for an existing private key
```
$ openssl req -out CSR.csr -key privateKey.key -new 
```

Generate a certificate signing request based on an existing certificate

$ openssl x509 -x509toreq -in certificate.crt -out CSR.csr -signkey privateKey.key

Remove a passphrase from a private key

$ openssl rsa -in privateKey.pem -out newPrivateKey.pem

Check a Certificate Signing Request (CSR)

$ openssl req -text -noout -verify -in CSR.csr

Check a certificate

$ openssl x509 -in certificate.crt -text -noout

Check a PKCS#12 file (.pfx or .p12)
```
$ openssl pkcs12 -info -in keyStore.p12
```

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.der

Convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM
```
$ openssl pkcs12 -in keyStore.pfx -out keyStore.pem -nodes
```

Convert a PEM certificate file and a private key to PKCS#12 (.pfx .p12)

$ openssl pkcs12 -export -out certificate.pfx -inkey privateKey.key -in certificate.crt -certfile CACert.crt

Extract Keys from PKCS#12 container

$ openssl pkcs12 -in yourP12File.pfx -nocerts -out privateKey.pem

Extract Certificates from PKCS#12 container

$ openssl pkcs12 -in yourP12File.pfx -clcerts -nokeys -out publicCert.pem

Verifying that a Certificate is issued by a CA

$  openssl verify -verbose -CAfile cacert.pem  server.crt