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require 'openssl'
module PuppetSpec
module SSL
PRIVATE_KEY_LENGTH = 2048
FIVE_YEARS = 5 * 365 * 24 * 60 * 60
CA_EXTENSIONS = [
["basicConstraints", "CA:TRUE", true],
["keyUsage", "keyCertSign, cRLSign", true],
["subjectKeyIdentifier", "hash", false],
["authorityKeyIdentifier", "keyid:always", false]
]
NODE_EXTENSIONS = [
["keyUsage", "digitalSignature", true],
["subjectKeyIdentifier", "hash", false]
]
DEFAULT_SIGNING_DIGEST = OpenSSL::Digest::SHA256.new
DEFAULT_REVOCATION_REASON = OpenSSL::OCSP::REVOKED_STATUS_KEYCOMPROMISE
ROOT_CA_NAME = "/CN=root-ca-\u{2070E}"
REVOKED_INT_CA_NAME = "/CN=revoked-int-ca-\u16A0"
INT_CA_NAME = "/CN=unrevoked-int-ca\u06FF\u16A0\u{2070E}"
LEAF_CA_NAME = "/CN=leaf-ca-\u06FF"
EXPLANATORY_TEXT = <<-EOT
# Root Issuer: #{ROOT_CA_NAME}
# Intermediate Issuer: #{INT_CA_NAME}
# Leaf Issuer: #{LEAF_CA_NAME}
EOT
def self.create_private_key(length = PRIVATE_KEY_LENGTH)
OpenSSL::PKey::RSA.new(length)
end
def self.self_signed_ca(key, name)
cert = OpenSSL::X509::Certificate.new
cert.public_key = key.public_key
cert.subject = OpenSSL::X509::Name.parse(name)
cert.issuer = cert.subject
cert.version = 2
cert.serial = rand(2**128)
not_before = just_now
cert.not_before = not_before
cert.not_after = not_before + FIVE_YEARS
ext_factory = extension_factory_for(cert, cert)
CA_EXTENSIONS.each do |ext|
extension = ext_factory.create_extension(*ext)
cert.add_extension(extension)
end
cert.sign(key, DEFAULT_SIGNING_DIGEST)
cert
end
def self.create_csr(key, name)
csr = OpenSSL::X509::Request.new
csr.public_key = key.public_key
csr.subject = OpenSSL::X509::Name.parse(name)
csr.version = 2
csr.sign(key, DEFAULT_SIGNING_DIGEST)
csr
end
def self.sign(ca_key, ca_cert, csr, extensions = NODE_EXTENSIONS)
cert = OpenSSL::X509::Certificate.new
cert.public_key = csr.public_key
cert.subject = csr.subject
cert.issuer = ca_cert.subject
cert.version = 2
cert.serial = rand(2**128)
not_before = just_now
cert.not_before = not_before
cert.not_after = not_before + FIVE_YEARS
ext_factory = extension_factory_for(ca_cert, cert)
extensions.each do |ext|
extension = ext_factory.create_extension(*ext)
cert.add_extension(extension)
end
cert.sign(ca_key, DEFAULT_SIGNING_DIGEST)
cert
end
def self.create_crl_for(ca_cert, ca_key)
crl = OpenSSL::X509::CRL.new
crl.version = 1
crl.issuer = ca_cert.subject
ef = extension_factory_for(ca_cert)
crl.add_extension(
ef.create_extension(["authorityKeyIdentifier", "keyid:always", false]))
crl.add_extension(
OpenSSL::X509::Extension.new("crlNumber", OpenSSL::ASN1::Integer(0)))
not_before = just_now
crl.last_update = not_before
crl.next_update = not_before + FIVE_YEARS
crl.sign(ca_key, DEFAULT_SIGNING_DIGEST)
crl
end
def self.revoke(serial, crl, ca_key)
revoked = OpenSSL::X509::Revoked.new
revoked.serial = serial
revoked.time = Time.now
revoked.add_extension(
OpenSSL::X509::Extension.new("CRLReason",
OpenSSL::ASN1::Enumerated(DEFAULT_REVOCATION_REASON)))
crl.add_revoked(revoked)
extensions = crl.extensions.group_by{|e| e.oid == 'crlNumber' }
crl_number = extensions[true].first
unchanged_exts = extensions[false]
next_crl_number = crl_number.value.to_i + 1
new_crl_number_ext = OpenSSL::X509::Extension.new("crlNumber",
OpenSSL::ASN1::Integer(next_crl_number))
crl.extensions = unchanged_exts + [new_crl_number_ext]
crl.sign(ca_key, DEFAULT_SIGNING_DIGEST)
crl
end
# Creates a self-signed root ca, then signs two node certs, revoking one of them.
# Creates an intermediate CA and one node cert off of it.
# Creates a second intermediate CA and one node cert off if it.
# Creates a leaf CA off of the intermediate CA, then signs two node certs revoking one of them.
# Revokes an intermediate CA.
# Returns the ca bundle, crl chain, and all the node certs
#
# -----
# / \
# / \
# | root +-------------------o------------------o
# \ CA / | |
# \ / | |
# --+-- | |
# | | |
# | | |
# | | |
# | --+-- --+--
# +---------+ | +---------+ / \ / \
# | revoked | | | | /revoked\ / \
# | node +--o---+ node | | int | | int |
# | | | | \ CA / \ CA /
# +---------+ +---------+ \ / \ /
# --+-- --+--
# | |
# | |
# | |
# --+-- |
# / \ +---+-----+
# / \ | |
# | leaf | | node |
# \ CA / | |
# \ / +---------+
# --+--
# |
# |
# +---------+ | +----------+
# | revoked | | | |
# | node +--o--+ node |
# | | | |
# +---------+ +----------+
def self.create_chained_pki
root_key = create_private_key
root_cert = self_signed_ca(root_key, ROOT_CA_NAME)
root_crl = create_crl_for(root_cert, root_key)
unrevoked_root_node_key = create_private_key
unrevoked_root_node_csr = create_csr(unrevoked_root_node_key, "/CN=unrevoked-root-node")
unrevoked_root_node_cert = sign(root_key, root_cert, unrevoked_root_node_csr)
revoked_root_node_key = create_private_key
revoked_root_node_csr = create_csr(revoked_root_node_key, "/CN=revoked-root-node")
revoked_root_node_cert = sign(root_key, root_cert, revoked_root_node_csr)
revoke(revoked_root_node_cert.serial, root_crl, root_key)
revoked_int_key = create_private_key
revoked_int_csr = create_csr(revoked_int_key, REVOKED_INT_CA_NAME)
revoked_int_cert = sign(root_key, root_cert, revoked_int_csr, CA_EXTENSIONS)
revoked_int_crl = create_crl_for(revoked_int_cert, revoked_int_key)
int_key = create_private_key
int_csr = create_csr(int_key, INT_CA_NAME)
int_cert = sign(root_key, root_cert, int_csr, CA_EXTENSIONS)
int_node_key = create_private_key
int_node_csr = create_csr(int_node_key, "/CN=unrevoked-int-node")
int_node_cert = sign(int_key, int_cert, int_node_csr)
unrevoked_int_node_key = create_private_key
unrevoked_int_node_csr = create_csr(unrevoked_int_node_key, "/CN=unrevoked-int-node")
unrevoked_int_node_cert = sign(revoked_int_key, revoked_int_cert, unrevoked_int_node_csr)
leaf_key = create_private_key
leaf_csr = create_csr(leaf_key, LEAF_CA_NAME)
leaf_cert = sign(revoked_int_key, revoked_int_cert, leaf_csr, CA_EXTENSIONS)
leaf_crl = create_crl_for(leaf_cert, leaf_key)
revoke(revoked_int_cert.serial, root_crl, root_key)
unrevoked_leaf_node_key = create_private_key
unrevoked_leaf_node_csr = create_csr(unrevoked_leaf_node_key, "/CN=unrevoked-leaf-node")
unrevoked_leaf_node_cert = sign(leaf_key, leaf_cert, unrevoked_leaf_node_csr)
revoked_leaf_node_key = create_private_key
revoked_leaf_node_csr = create_csr(revoked_leaf_node_key, "/CN=revoked-leaf-node")
revoked_leaf_node_cert = sign(leaf_key, leaf_cert, revoked_leaf_node_csr)
revoke(revoked_leaf_node_cert.serial, leaf_crl, leaf_key)
ca_bundle = bundle(root_cert, revoked_int_cert, leaf_cert)
crl_chain = bundle(root_crl, revoked_int_crl, leaf_crl)
{
:root_cert => root_cert,
:int_cert => int_cert,
:int_node_cert => int_node_cert,
:leaf_cert => leaf_cert,
:leaf_key => leaf_key,
:revoked_root_node_cert => revoked_root_node_cert,
:revoked_int_cert => revoked_int_cert,
:revoked_leaf_node_cert => revoked_leaf_node_cert,
:unrevoked_root_node_cert => unrevoked_root_node_cert,
:unrevoked_int_node_cert => unrevoked_int_node_cert,
:unrevoked_leaf_node_cert => unrevoked_leaf_node_cert,
:ca_bundle => ca_bundle,
:crl_chain => crl_chain,
}
end
private
def self.just_now
Time.now - 1
end
def self.extension_factory_for(ca, cert = nil)
ef = OpenSSL::X509::ExtensionFactory.new
ef.issuer_certificate = ca
ef.subject_certificate = cert if cert
ef
end
def self.bundle(*items)
items.map {|i| EXPLANATORY_TEXT + i.to_pem }.join("\n")
end
end
end
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