Use certificate with proper subjectAltName (Chrome 58 compatibility)

[padde]

Problem description

Dotjs stopped working with Chrome 58. Chrome will no longer accept a certificate without subjectAltName and will display this error instead:

Attackers might be trying to steal your information from localhost (for example, passwords, messages or credit cards). NET::ERR_CERT_COMMON_NAME_INVALID

This server could not prove that it is localhost; its security certificate is from [missing_subjectAltName]. This may be caused by a misconfiguration or an attacker intercepting your connection.

For the announcement, see https://groups.google.com/a/chromium.org/forum/#!msg/security-dev/IGT2fLJrAeo/csf_1Rh1AwAJ

How the valid self-signed certificate was generated

For future reference, the openssl command used to generate the certificate was based on this StackOverflow post:

openssl req -config localhost.conf -new -x509 -sha256 -newkey rsa:2048 -nodes \
    -keyout localhost.key.pem -days 36500 -out localhost.cert.pem

# localhost.conf

[ req ]
default_bits        = 2048
default_keyfile     = server-key.pem
distinguished_name  = subject
req_extensions      = req_ext
x509_extensions     = x509_ext
string_mask         = utf8only

[ subject ]
countryName         = Country Name (2 letter code)
countryName_default     = US
stateOrProvinceName     = State or Province Name (full name)
stateOrProvinceName_default = NY
localityName            = Locality Name (eg, city)
localityName_default        = Localhost
organizationName         = Organization Name (eg, company)
organizationName_default    = Localhost
commonName          = Common Name (e.g. server FQDN or YOUR name)
commonName_default      = Localhost
emailAddress            = Email Address
emailAddress_default        = localhost@example.com

[ x509_ext ]

subjectKeyIdentifier        = hash
authorityKeyIdentifier  = keyid,issuer
basicConstraints        = CA:FALSE
keyUsage            = digitalSignature, keyEncipherment
subjectAltName          = @alternate_names
nsComment           = "OpenSSL Generated Certificate"

[ req_ext ]
subjectKeyIdentifier        = hash
basicConstraints        = CA:FALSE
keyUsage            = digitalSignature, keyEncipherment
subjectAltName          = @alternate_names
nsComment           = "OpenSSL Generated Certificate"

[ alternate_names ]
DNS.1 = localhost
DNS.2 = 127.0.0.1
DNS.3 = ::1

[keith]

This still works for me with chrome 71