    This directory, tests/standalone/io/certificates, contains the
X509 TLS certificates and private keys needed to run tests of Dart's
secure networking code.  The SecureSocket and SecureServer classes
are tested by making TLS (formerly called SSL) connections, secured
by certificates from a self-signed test root authority.

The certificates are created by running ../create_sample_certificates.sh
in a bash or sh shell, with the openssl tools installed.  Run the script
twice to create the untrusted_* files.

PEM files:

server_chain.pem:
  Contains the chain of certificates, from the self-signed
test certificate authority, through the intermediate CA, to the server
certificate, used on the server side of a test connection.

server_key.pem:
  Contains the private key for the server certificate

trusted_certs.pem:
  Contains the self-signed certificate of the test certificate authority.
This certificate is set as "trusted" by the client side of the connection
in its SecurityContext object, so that a verified TLS connection to the
server can be made.

untrusted_server_chain.pem:
  Contains a chain of certificates, from a different self-signed
test certificate authority, through an intermediate CA, to a server
certificate, used on the server side of a test connection that is intended
to fail because the client does not accept this certificate authority

untrusted_server_key.pem:
  Contains the private key for the untrusted server certificate
in untrusted_server_chain.pem

*_malformed.pem:
  Truncated PEM formatted certificates used to test error handling.

PKCS12 files:

server_key.12:
  Created with:
  $ openssl pkcs12 -export -inkey server_key.pem -out server_key.p12 -nocerts
  with password 'dartdart'

server_chain.p12:
  Created with:
  $ openssl pkcs12 -export -in server_chain.pem -out server_chain.p12 -nokeys
  with password 'dartdart'

client1_key.p12:
  Created with:
  $ openssl pkcs12 -export -inkey client1_key.pem -out client1_key.p12 -nocerts
  with password 'dartdart'

client1.p12:
  Created with:
  $ openssl pkcs12 -export -in client1.pem -out client1.p12 -nokeys
  with password 'dartdart'

trusted_certs.p12:
  Created with:
  $ openssl pkcs12 -export -in trusted_certs.pem -out trusted_certs.p12 -nokeys
  with password 'dartdart'

client_authority.p12:
  Created with:
  $ openssl pkcs12 -export -in client_authority.pem -out client_authority.p12 -nokeys
  with password 'dartdart'