# 0-dns ## Purpose The test cert file for use `test/parallel/test-tls-0-dns-altname.js` can be created by using `asn1.js` and `asn1.js-rfc5280`, ## How to create a test cert. ```sh $ openssl genrsa -out 0-dns-key.pem 2048 Generating RSA private key, 2048 bit long modulus ...................+++ ..............................................................................................+++ e is 65537 (0x10001) $ openssl rsa -in 0-dns-key.pem -RSAPublicKey_out -outform der -out 0-dns-rsapub.der writing RSA key $ npm install 0-dns@1.0.0 /home/github/node/test/fixtures/0-dns +-- asn1.js@4.9.1 | +-- bn.js@4.11.6 | +-- inherits@2.0.3 | `-- minimalistic-assert@1.0.0 `-- asn1.js-rfc5280@1.2.2 $ node ./createCert.js $ openssl x509 -text -in 0-dns-cert.pem (You can not see evil.example.com in subjectAltName field) ```