stripe-ruby/lib/stripe/certificate_blacklist.rb
2014-04-10 12:44:16 -07:00

56 lines
1.7 KiB
Ruby

require 'uri'
require 'digest/sha1'
module Stripe
module CertificateBlacklist
BLACKLIST = {
"api.stripe.com" => [
'05c0b3643694470a888c6e7feb5c9e24e823dc53',
],
"revoked.stripe.com" => [
'5b7dc7fbc98d78bf76d4d4fa6f597a0c901fad5c',
]
}
# Preflight the SSL certificate presented by the backend. This isn't 100%
# bulletproof, in that we're not actually validating the transport used to
# communicate with Stripe, merely that the first attempt to does not use a
# revoked certificate.
# Unfortunately the interface to OpenSSL doesn't make it easy to check the
# certificate before sending potentially sensitive data on the wire. This
# approach raises the bar for an attacker significantly.
def self.check_ssl_cert(uri, ca_file)
uri = URI.parse(uri)
sock = TCPSocket.new(uri.host, uri.port)
ctx = OpenSSL::SSL::SSLContext.new
ctx.set_params(:verify_mode => OpenSSL::SSL::VERIFY_PEER,
:ca_file => ca_file)
socket = OpenSSL::SSL::SSLSocket.new(sock, ctx)
socket.connect
certificate = socket.peer_cert.to_der
fingerprint = Digest::SHA1.hexdigest(certificate)
if blacklisted_certs = BLACKLIST[uri.host]
if blacklisted_certs.include?(fingerprint)
raise APIConnectionError.new(
"Invalid server certificate. You tried to connect to a server that" +
"has a revoked SSL certificate, which means we cannot securely send" +
"data to that server. Please email support@stripe.com if you need" +
"help connecting to the correct API server."
)
end
end
socket.close
return true
end
end
end