项目详情
TDX Guest
This project offers libraries for a simple wrapper around quote providing tools
such as the go-configfs-tsm library, or the /dev/tdx_guest device in Linux,
as well as a library for attestation verification of fundamental components of
an attestation quote.
This project is split into two complementary roles. The first role is producing
an attestation quote, and the second is checking an attestation quote. Theclient library produces quote, the verify library verifies quote's
signatures and certificates.
client
This library should be used within the confidential workload to collect an
attestation quote along with requisite certificates.
Your main interactions with it will be to first get the quote provider, or
open the device, then get an attestation quote with your provided 64 bytes of
user data (typically a nonce), and then close the device. For convenience, the
attestation with its associated certificates can be collected in a
wire-transmittable protocol buffer format.
func GetQuoteProvider() (*LinuxConfigFsQuoteProvider, error)
This function creates an instance of a quote provider which uses the go-configfs-tsm
library to fetch attestation quotes via ConfigFS.
func OpenDevice() (*LinuxDevice, error)
This function creates a file descriptor to the /dev/tdx_guest device and
returns an object that has methods encapsulating commands to the device. When
done, remember to Close() the device.
Note:- The Device interface is deprecated, and use of quote provider interface
is recommended for fetching attestation quote.
func GetQuote(quoteProvider any, reportData [64]byte) (any, error)
This function takes an object implementing either the QuoteProvider interface
(e.g. LinuxConfigFsQuoteProvider), or the Device interface (e.g., a LinuxDevice)
along with report data which typically consists of a nonce value.
It returns the protocol buffer representation of the attestation quote.
You can use GetRawQuote to get the TDX Quote in byte array format.
func (d Device) Close() error
Closes the device.
verify
This library will check the signature, certificate chain and basic
well-formedness properties of an attestation quote. The requirements for quote
well-formedness come from the Intel TDX specification,
and the requirements for certificate well-formedness come from the
Intel PCK Certificate specification.
The presence of the PCK Certificate Chain within the input attestation quote is
expected.
func TdxQuote(quote *pb.QuoteV4, options *Options) error
This function verifies that the attestation has a valid signature and
certificate chain. It provides an optional verification against the collateral
obtained from the Intel PCS API and also offers an optional check against
the certificate revocation list (CRL). By default, the option to verify against
collaterals and the certificate revocation list(CRL) is disabled. The
verification using collaterals is based on Intel PCS API specification
documentation.
Example expected invocation:
verify.TdxQuote(myAttestation, verify.Options())Options type
This type contains six fields:
GetCollateral bool: if true, thenTdxQuotewill download the collateral
from Intel PCS API service and check against collateral obtained.
Must betrueifCheckRevocationsis true.CheckRevocations bool: if true, thenTdxQuotewill download the
certificate revocation list (CRL) from Intel PCS API service and check for
revocations.Getter HTTPSGetter: ifnil, usesDefaultHTTPSGetter().
TheHTTPSGetterinterface consists of a single method `Get(url string)
(map[string][]string, []byte, error)` that should return the headers and body
of the HTTPS response.Now *TimeSet: ifnil, usesdefaultTimeSet(). It is the set of times at
which to verify the validity of certificates and collaterals.TrustedRoots *x509.CertPool: ifnil, uses the library's embedded
certificate.
Certificate chain verification is performed using trusted roots.DisableTcbStatusCheck bool: if true, thenTdxQuotewill NOT check the TCB
status reported by Intel PCS. Default isfalse.
rtmr
This library should be used within the confidential workload to perform a hash
extend operation into the TDX RTMR register.
func ExtendEventLog(rtmrIndex int, hashAlgo crypto.Hash, eventLog []byte) error
This function calculates the hash digest of a provided event log and extends it
in the corresponding RTMR register. However, it's important to note that TDX
currently only supports the SHA-384 hash algorithm. If hashAlgo is not SHA-384,
the function will return an error.
func ExtendDigest(rtmrIndex int, digest []byte) error
This function extends a SHA-384 digest into the corresponding RTMR register.
If the length of the given digest does not match that of a SHA-384 digest,
the function will return an error.
License
go-tdx-guest is released under the Apache 2.0 license.
Copyright 2023 Google LLC
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.Links
Disclaimers
This is not an officially supported Google product.
