mirror of
https://github.com/kairos-io/tpm-helpers.git
synced 2025-07-07 19:48:37 +00:00
83 lines
2.0 KiB
Go
83 lines
2.0 KiB
Go
/*
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** Copyright 2019 Bloomberg Finance L.P.
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**
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** Licensed under the Apache License, Version 2.0 (the "License");
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** you may not use this file except in compliance with the License.
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** You may obtain a copy of the License at
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**
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** http://www.apache.org/licenses/LICENSE-2.0
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**
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** Unless required by applicable law or agreed to in writing, software
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** distributed under the License is distributed on an "AS IS" BASIS,
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** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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** See the License for the specific language governing permissions and
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** limitations under the License.
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*/
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package tpm
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import (
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"crypto/sha256"
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"encoding/pem"
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"fmt"
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"github.com/google/certificate-transparency-go/x509"
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"github.com/google/go-attestation/attest"
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)
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// AttestationData is used to generate challanges from EKs
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type AttestationData struct {
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EK []byte
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AK *attest.AttestationParameters
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}
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// Challenge represent the struct returned from the ws server,
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// used to resolve the TPM challenge.
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type Challenge struct {
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EC *attest.EncryptedCredential
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}
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// ChallengeResponse represent the struct returned to the ws server
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// as a challenge response.
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type ChallengeResponse struct {
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Secret []byte
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}
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// DecodePubHash returns the public key from an attestation EK
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func DecodePubHash(ek *attest.EK) (string, error) {
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data, err := pubBytes(ek)
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if err != nil {
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return "", err
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}
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pubHash := sha256.Sum256(data)
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hashEncoded := fmt.Sprintf("%x", pubHash)
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return hashEncoded, nil
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}
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func encodeEK(ek *attest.EK) ([]byte, error) {
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if ek.Certificate != nil {
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return pem.EncodeToMemory(&pem.Block{
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Type: "CERTIFICATE",
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Bytes: ek.Certificate.Raw,
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}), nil
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}
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data, err := pubBytes(ek)
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if err != nil {
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return nil, err
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}
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return pem.EncodeToMemory(&pem.Block{
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Type: "PUBLIC KEY",
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Bytes: data,
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}), nil
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}
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func pubBytes(ek *attest.EK) ([]byte, error) {
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data, err := x509.MarshalPKIXPublicKey(ek.Public)
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if err != nil {
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return nil, fmt.Errorf("error marshaling ec public key: %v", err)
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}
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return data, nil
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}
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