Add a function to validate an x509 RSA key pair

Add a function to validate an x509 RSA certificate and key pair, as
commonly used for TLS certificates.

The rationale behind this is that we store our TLS certificates and
private keys in Hiera YAML files, and poor indentation or formatting in
the YAML file could cause a valid certificate to be considered invalid.

Will cause the Puppet run to fail if:

- an invalid certificate is detected
- an invalid RSA key is detected
- the certificate does not match the key, i.e. the certificate
  has not been signed by the supplied key

The test certificates I've used in the spec tests were generated using
the Go standard library:

    $ go run $GOROOT/src/crypto/tls/generate_cert.go -host localhost

Example output:

    ==> cache-1.router: Error: Not a valid RSA key: Neither PUB key nor PRIV key:: nested asn1 error at /var/govuk/puppet/modules/nginx/manifests/config/ssl.pp:30 on node cache-1.router.dev.gov.uk
This commit is contained in:
Matt Bostock 2015-11-23 23:45:23 +00:00
parent ef0c13b1af
commit 97320ab421
3 changed files with 217 additions and 0 deletions

View file

@ -1182,6 +1182,22 @@ Instead, use:
*Type*: statement.
#### `validate_x509_rsa_key_pair`
Validates a PEM-formatted X.509 certificate and private key using OpenSSL.
Verifies that the certficate's signature was created from the supplied key.
Fails catalog compilation if any value fails this check.
Takes two arguments, the first argument must be a X.509 certificate and the
second must be an RSA private key:
~~~
validate_x509_rsa_key_pair($cert, $key)
~~~
*Type*: statement.
#### `values`
Returns the values of a given hash. For example, given `$hash = {'a'=1, 'b'=2, 'c'=3} values($hash)` returns [1,2,3].

View file

@ -0,0 +1,47 @@
module Puppet::Parser::Functions
newfunction(:validate_x509_rsa_key_pair, :doc => <<-ENDHEREDOC
Validates a PEM-formatted X.509 certificate and RSA private key using
OpenSSL. Verifies that the certficate's signature was created from the
supplied key.
Fail compilation if any value fails this check.
validate_x509_rsa_key_pair($cert, $key)
ENDHEREDOC
) do |args|
require 'openssl'
NUM_ARGS = 2 unless defined? NUM_ARGS
unless args.length == NUM_ARGS then
raise Puppet::ParseError,
("validate_x509_rsa_key_pair(): wrong number of arguments (#{args.length}; must be #{NUM_ARGS})")
end
args.each do |arg|
unless arg.is_a?(String)
raise Puppet::ParseError, "#{arg.inspect} is not a string."
end
end
begin
cert = OpenSSL::X509::Certificate.new(args[0])
rescue OpenSSL::X509::CertificateError => e
raise Puppet::ParseError, "Not a valid x509 certificate: #{e}"
end
begin
key = OpenSSL::PKey::RSA.new(args[1])
rescue OpenSSL::PKey::RSAError => e
raise Puppet::ParseError, "Not a valid RSA key: #{e}"
end
unless cert.verify(key)
raise Puppet::ParseError, "Certificate signature does not match supplied key"
end
end
end

View file

@ -0,0 +1,154 @@
require 'spec_helper'
describe 'validate_x509_rsa_key_pair' do
let(:valid_cert) do
<<EOS
-----BEGIN CERTIFICATE-----
MIIC9jCCAeCgAwIBAgIRAK11n3X7aypJ7FPM8UFyAeowCwYJKoZIhvcNAQELMBIx
EDAOBgNVBAoTB0FjbWUgQ28wHhcNMTUxMTIzMjIzOTU4WhcNMTYxMTIyMjIzOTU4
WjASMRAwDgYDVQQKEwdBY21lIENvMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIB
CgKCAQEAz9bY/piKahD10AiJSfbI2A8NG5UwRz0r9T/WfvNVdhgrsGFgNQjvpUoZ
nNJpQIHBbgMOiXqfATFjJl5FjEkSf7GUHohlGVls9MX2JmVvknzsiitd75H/EJd+
N+k915lix8Vqmj8d1CTlbF/8tEjzANI67Vqw5QTuqebO7rkIUvRg6yiRfSo75FK1
RinCJyl++kmleBwQZBInQyg95GvJ5JTqMzBs67DeeyzskDhTeTePRYVF2NwL8QzY
htvLIBERTNsyU5i7nkxY5ptUwgFUwd93LH4Q19tPqL5C5RZqXxhE51thOOwafm+a
W/cRkqYqV+tv+j1jJ3WICyF1JNW0BQIDAQABo0swSTAOBgNVHQ8BAf8EBAMCAKAw
EwYDVR0lBAwwCgYIKwYBBQUHAwEwDAYDVR0TAQH/BAIwADAUBgNVHREEDTALggls
b2NhbGhvc3QwCwYJKoZIhvcNAQELA4IBAQAzRo0hpVTrFQZLIXpwvKwZVGvJdCkV
P95DTsSk/VTGV+/YtxrRqks++hJZnctm2PbnTsCAoIP3AMx+vicCKiKrxvpsLU8/
+6cowUbcuGMdSQktwDqbAgEhQlLsETll06w1D/KC+ejOc4+LRn3GQcEyGDtMk/EX
IeAvBZHr4/kVXWnfo6kzCLcku1f8yE/yDEFClZe9XV1Lk/s+3YfXVtNnMJJ1giZI
QVOe6CkmuQq+4AtIeW8aLkvlfp632jag1F77a1y+L268koKkj0hBMrtcErVQaxmq
xym0+soR4Tk4pTIGckeFglrLxkP2JpM/yTwSEAVlmG9vgTliYKyR0uMl
-----END CERTIFICATE-----
EOS
end
let(:valid_key) do
<<EOS
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
EOS
end
let(:another_valid_key) do
<<EOS
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----
EOS
end
let(:valid_cert_but_indented) do
valid_cert.gsub(/^/, ' ')
end
let(:valid_key_but_indented) do
valid_key.gsub(/^/, ' ')
end
let(:bad_cert) do
'foo'
end
let(:bad_key) do
'bar'
end
context 'function signature validation' do
it { is_expected.not_to eq(nil) }
it { is_expected.to run.with_params().and_raise_error(Puppet::ParseError, /wrong number of arguments/i) }
it { is_expected.to run.with_params(0, 1, 2, 3).and_raise_error(Puppet::ParseError, /wrong number of arguments/i) }
end
context 'valid input' do
describe 'valid certificate and key' do
it { is_expected.to run.with_params(valid_cert, valid_key) }
end
end
context 'bad input' do
describe 'valid but indented certificate, valid key' do
it { is_expected.to run.with_params(valid_cert_but_indented, valid_key).and_raise_error(Puppet::ParseError, /Not a valid x509 certificate/) }
end
describe 'valid certificate, valid but indented key' do
it { is_expected.to run.with_params(valid_cert, valid_key_but_indented).and_raise_error(Puppet::ParseError, /Not a valid RSA key/) }
end
describe 'valid certificate, bad key' do
it { is_expected.to run.with_params(valid_cert, bad_key).and_raise_error(Puppet::ParseError, /Not a valid RSA key/) }
end
describe 'bad certificate, valid key' do
it { is_expected.to run.with_params(bad_cert, valid_key).and_raise_error(Puppet::ParseError, /Not a valid x509 certificate/) }
end
describe 'validate certificate and key; certficate not signed by key' do
it { is_expected.to run.with_params(valid_cert, another_valid_key).and_raise_error(Puppet::ParseError, /Certificate signature does not match supplied key/) }
end
describe 'valid cert and key but arguments in wrong order' do
it { is_expected.to run.with_params(valid_key, valid_cert).and_raise_error(Puppet::ParseError, /Not a valid x509 certificate/) }
end
describe 'non-string arguments' do
it { is_expected.to run.with_params({}, {}).and_raise_error(Puppet::ParseError, /is not a string/) }
it { is_expected.to run.with_params(1, 1).and_raise_error(Puppet::ParseError, /is not a string/) }
it { is_expected.to run.with_params(true, true).and_raise_error(Puppet::ParseError, /is not a string/) }
it { is_expected.to run.with_params("foo", {}).and_raise_error(Puppet::ParseError, /is not a string/) }
it { is_expected.to run.with_params(1, "bar").and_raise_error(Puppet::ParseError, /is not a string/) }
it { is_expected.to run.with_params("baz", true).and_raise_error(Puppet::ParseError, /is not a string/) }
end
end
end