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Add Enrollment tutorial; describe more TPM commands
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@ -64,6 +64,26 @@ Attestation is done by a client computer with a TPM interacting with an
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attestation service over a network. This requires a network protocol
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for attestation.
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## Intended Audience
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Readers should have read the [TPM introduction tutorial](/Intro/README.md).
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## Enrollment
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[Enrollment](/Enrollment/README.md) is the process and protocol for
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onboarding devices into a network / organization. For example, adding
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an IoT to a home network, a server to a data center, a smartphone or
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tablet or laptop to a persons set of personal devices, etc.
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Generally attestation protocols apply to enrolled devices. Enrollment
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protocols _may_ be very similar to attestation protocols, or even
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actually be sub-protocols of attestation protocols. Enrollment
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protocols can also be separate from attestation altogether.
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This tutorial mostly covers only attestation of/by enrolled devices.
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For more about enrollment see the tutorial specifically for
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[enrollment](/Enrollment/README.md).
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## Notation
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- `Encrypt_<name>` == encryption with the named private or secret key
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@ -78,6 +98,70 @@ for attestation.
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- `{"key":<value>,...}` == JSON text
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- `TPM2_MakeCredential(<args>)` == outputs of calling `TPM2_MakeCredential()` with `args` arguments
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- `TPM2_Certify(<args>)` == outputs of calling `TPM2_Certify()` with `args` arguments
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- `XK` == `<X>` key, for some `<X>` purpose (the TPM-resident object and its private key)
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- `EK` == endorsement key (the TPM-resident object and its private key)
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- `AK` == attestation key (the TPM-resident object and its private key)
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- `TK` == transport key (the TPM-resident object and its private key)
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- `XKpub` == `<X>`'s public key, for some `<X>` purpose
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- `EKpub` == endorsement public key
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- `AKpub` == attestation public key
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- `TKpub` == transport public key
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- `XKname` == `<X>`'s cryptographic name, for some `<X>` purpose
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- `EKname` == endorsement key's cryptographic name
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- `AKname` == attestation key's cryptographic name
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## Threat Models
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Some threats that an attestation protocol and implementation may want to
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address:
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- attestation client impersonation
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- attestation server impersonation
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- unauthorized firmware and/or OS updates
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- theft or compromise of of attestation servers
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- theft of client devices or their local storage (e.g., disks, JBODs)
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- theft of client devices by adversaries capable of decapping and
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reading the client's TPM's NVRAM
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The attestation protocols we discuss will provide at least partial
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protection against impersonation of attestation clients: once a TPM's
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EKpub/EKcert are bound to the device in the attestation server's
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database, that TPM can only be used for that device and no others.
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All the attestation protocols we discuss will provide protection against
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unauthorized firmware and/or OS updates via attestation of root of trust
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measurements (RTM).
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The attestation protocols we discuss will provide protection against
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impersonation of attestation servers without necessarily authenticating
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the servers to the clients in traditional ways (e.g., using TLS server
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certificates). The role of the attestation server will be to deliver to
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clients secrets and credentials they need that can only be correct and
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legitimate if the server is authentic. As well, an attestation server
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may unlock network access for a client, something only an authentic
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server could do.
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We will show how an attestation server can avoid storing any cleartext
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secrets.
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Theft of _running_ client devices cannot be fully protected against by
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an attestation protocol. The client must detect being taken from its
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normal environment and shutdown in such a way that no secrets are left
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in cleartext on any of its devices. Frequent attestations might be used
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to detect theft of a client, but other keepalive signalling options are
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possible.
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Theft of non-running client devices can be protected against by having
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the client shutdown in such a way that no secrets are left in cleartext
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on any of its devices. Such client devices may be configured to need
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the help of an attestation server to recover the secrets it needs for
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normal operation.
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Full protection against decapping of TPM chips is not possible, but
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protection against off-line use of secrets stolen from TPM chips is
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possible by requiring that the client be on-line and attest in order to
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obtain secrets that it needs to operate. This allows for revocation of
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stolen clients, which would result in attestation protocol failures.
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## Proof of Possession of TPM
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@ -314,7 +398,7 @@ is persisted both, in the client TPM and in the attestation service's
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database:
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```
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<having previously successfully enrolled AKpub and bound it to EKpub...>
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<having previously successfully enrolled>
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CS0: timestamp, AKpub, PCRs, eventlog,
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TPM2_Quote(AK, PCRs, extra_data)=Signed_AK({hash-of-PCRs, misc, extra_data})
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@ -505,10 +589,6 @@ PCRs are desired, then this becomes a one round trip protocol.
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An AKcert will be added to the Safeboot protocol soon.
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### Actual Protocols: ...
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(TBD)
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## Attestation Protocol Patterns and Actual Protocols (signing-only EKs)
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Some TPMs come provisioned with signing-only endorsement keys in
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@ -609,8 +689,8 @@ A schema for the attestation server's database entries might look like:
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"previous_PCRs": "<...>",
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"proposed_PCRs": "<...>",
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"ak_cert_template": "<AKCertTemplate>",
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"secrets": "<secrets>",
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"resetCount": "<resetCount value from last quote>"
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"resetCount": "<resetCount value from last quote>",
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"secrets": "<see below>"
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}
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```
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@ -660,12 +740,28 @@ then an administrator would confirm that the client just did a
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firmware/OS upgrade and if so replace the `previous_PCRs` with the
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`proposed_PCRs`, then the client could attempt attestation again.
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## Dealing with Secrets
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# Delivery of Secrets to Attestation Clients
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An attestation server might want to return storage/filesystem decryption
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key-encryption-keys to a client. But one might not want to store those
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keys in the clear on the attestation server. As well, one might want a
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break-glass way to recover those secrets.
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An attestation server might have to return storage/filesystem decryption
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key-encryption-keys (KEKs) to a client. But one might not want to store
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those keys in the clear on the attestation server. As well, one might
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want a break-glass way to recover those secrets.
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Possible goals:
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- store secrets that clients need on the attestation server
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- do not store plaintext or plaintext-equivalent secrets on the
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attestation server
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- allow for adding more secrets to send to the client after enrollment
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- provide a break-glass recovery mechanism
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Note that in all cases the client does get direct access to various
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secrets. Using a TPM to prevent direct software access to those secrets
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would not be performant if, for example, those secrets are being used to
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encrypt filesystems. We must inherently trust the client to keep those
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secrets safe when running.
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## Break-Glass Recovery
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For break-glass recovery, the simplest thing to do is to store
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`Encrypt_backupKey({EKpub, hostname, secrets})`, where `backupKey` is an
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@ -675,53 +771,252 @@ the ciphertext to the offline system where the private backup key is
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kept, decrypt it, and then use the secrets manually to recover the
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affected system.
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Here are some ideas for how to make an attestation client depend on the
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attestation server giving it keys needed to continue booting after
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successful attestation:
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## Secret Transport Sub-Protocols
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- Store `TPM2_MakeCredential(EKpub, someObjectName, key0), Encrypt_key0(secrets)`.
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Here we describe several possible sub-protocols of attestation protocols
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for secret transport. This list is almost certainly not exhaustive.
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In this mode the server sends the client the stored data, then client
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gets to recreate `someObject` (possibly by loading a saved object or
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by re-creating it on the same non-NULL hierarchy from the same
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primary seed using the same template and extra entropy) on its TPM so
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that the corresponding call to `TPM2_ActivateCredential()` can
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succeed, then the client recovers `key0` and decrypts the encrypted
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secrets. Here `someObject` can be trivial and need only exist to
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make the `{Make,Activate}Credential` machinery work.
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### Store a `TPM2_MakeCredential()` Payload
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TPM replacement and/or migration of a host from one physical system
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to another can be implemented by learning the new system's TPM's
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EKpub and using the offline `backupKey` to compute
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`TPM2_MakeCredential(EKpub_new, someObjectName, key0)` and update the
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host's entry.
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[`TPM2_MakeCredential()`](/TPM-Commands/TPM2_MakeCredential.md) and
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[`TPM2_ActivateCredential()`](/TPM-Commands/TPM2_ActivateCredential.md)
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can use any kind of loaded object with a private area as the "credential
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object name" and "credential object handle" arguments of the two calls,
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respectively. During attestation we need to use an AK for this object
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due to the need to have a signature key for
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[`TPM2_Quote()`](/TPM-Commands/TPM2_Quote.md), and we want that AK to
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have `stClear` set, meaning that it is ephemeral, rendering the outputs
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of `TPM2_MakeCredential(EKpub, AKname, secrets)` ephemeral as well,
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therefore `TPM2_MakeCredential(EKpub, AKname, secrets)` must be called
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on each attestation, which means the `secrets` also have to be ephemeral
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or else must be stored in cleartext on the attestation server.
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- Alternatively generate a non-restricted decryption private key using
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a set template and extra entropy, on the same non-NULL hierarchy
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(i.e., from the same seed), enroll the public key to this private key
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in an attestation protocol, and have the attestation server store
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secrets encrypted to that public key.
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However, we can use a key that does not have `stClear` set as the
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credential object. A long-term key that survives reboots.
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(The EK cannot be used this way because it is restricted.)
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> We'd like to use the EK itself, however,
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> [that is not actually possible](https://github.com/tpm2-software/tpm2-tools/issues/1883)
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> because the `activateHandle` argument to
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> [`TPM2_ActivateCredential()`](/TPM-Commands/TPM2_ActivateCredential.md)
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> requires `ADMIN` role, and on most TPMs the auth policy for the EK
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> does not provide any way to satisfy it for this usage. Though in
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> principle this should be possible, and it would be very convenient if
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> it was.
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- Store a secret value that will be extended into an application PCR
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that is used as a policy PCR for unsealing a persistent object stored
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on the client's TPM.
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So for this approach one has to create a long-term attestation key that
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we shall call the `LTAK`, and then the server can store
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`TPM2_MakeCredential(EKpub, LTAKname, secrets)` without knowing the
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secrets.
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In this mode the server sends the client the secret PCR extension
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value, and the client uses it to extend a PCR such that it can then
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unseal the real storage / filesystem decryption keys.
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The client has to use
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[`TPM2_CreatePrimary()`](/TPM-Commands/TPM2_CreatePrimary.md) or
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[`TPM2_CreateLoaded()`](/TPM-Commands/TPM2_CreateLoaded.md) in order to
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deterministically create the same `LTAK` (again, without the `stClear`
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attribute), else if it uses
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[`TPM2_Create()`](/TPM-Commands/TPM2_Create.md) then it must store the
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key save file somewhere (possibly in the attestation server!) or make
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the key object persistent.
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Using a PCR and a policy on the key object allows for a clever
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break-glass secret recovery mechanism by using a compound extended
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authorization (EA) policy that allows either unsealing based on a
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PCR, or maybe based on an password-based HMAC (with machine passwords
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stored in a safe).
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```
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<having previously successfully enrolled
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and saved
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long_term_Credential =
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TPM2_MakeCredential(EKpub, LTAKname, secrets_key) ||
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Encrypt_secrets_key(long_term_secrets)>
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- A hybrid of the previous options, where the server stores a secret
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PCR extension value wrapped with `TPM2_MakeCredential()`.
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CS0: timestamp, AKpub, PCRs, eventlog,
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TPM2_Quote(AK, PCRs, extra_data)=Signed_AK({hash-of-PCRs, misc, extra_data})
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SC0: {TPM2_MakeCredential(EKpub, AKname, session_key),
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Encrypt_session_key(long_term_Credential)}
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```
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Other ideas?
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New secrets can be added at any time without interaction with the
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client if the attestation server recalls the `LTAKname`.
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The schema for storing secrets transported this way would be:
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```JSON
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{
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"EKpub": "<EKpub>",
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"hostname": "<hostname>",
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"EKcert": "<EKcert in PEM, if available>",
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"previous_firmware_profile": "FWProfile0",
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"current_firmware_profiles": ["FWProfile1", "FWProfile2", "..."],
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"previous_operating_system_profiles": "OSProfile0",
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"current_operating_system_profiles": ["OSProfile1", "OSProfile2", "..."],
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"previous_PCRs": "<...>",
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"proposed_PCRs": "<...>",
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"ak_cert_template": "<AKCertTemplate>",
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"resetCount": "<resetCount value from last quote>",
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"secret store and transport fields":"vvvvvvvvvvvvvvvvvv",
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"LTAKname": "<...>",
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"secrets": ["<MakeCredential_0>", "<MakeCredential_1>", "..", "<MakeCredential_N>"]
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"secrets_backup": ["<RSA_Encrypt_to_backup_key(...)", "..."],
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}
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```
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### Use an Unrestricted Decryption Transport Key (TK) for Secret Transport (client-side)
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Another option is to generate an asymmetric key-pair at device
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enrollment time (we shall call this the "transport key", or `TK`), and
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store:
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- the `TKpub`, and
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- zero, one, or more secrets encrypted in the `EKpub`.
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The client has to use
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[`TPM2_CreatePrimary()`](/TPM-Commands/TPM2_CreatePrimary.md) or
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[`TPM2_CreateLoaded()`](/TPM-Commands/TPM2_CreateLoaded.md) in order to
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deterministically create the same `TK` (without the `stClear`)
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attribute, else if it uses
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[`TPM2_Create()`](/TPM-Commands/TPM2_Create.md) then it must store the
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key save file somewhere (possibly in the attestation server!) or make
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the key object persistent.
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New secrets can be added at any time without interaction with the
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client.
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```JSON
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{
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"EKpub": "<EKpub>",
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"hostname": "<hostname>",
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"EKcert": "<EKcert in PEM, if available>",
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"previous_firmware_profile": "FWProfile0",
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"current_firmware_profiles": ["FWProfile1", "FWProfile2", "..."],
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"previous_operating_system_profiles": "OSProfile0",
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"current_operating_system_profiles": ["OSProfile1", "OSProfile2", "..."],
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"previous_PCRs": "<...>",
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"proposed_PCRs": "<...>",
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"ak_cert_template": "<AKCertTemplate>",
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"resetCount": "<resetCount value from last quote>",
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"secret store and transport fields":"vvvvvvvvvvvvvvvvvv",
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"TKpub": "<TKpub in PEM>",
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"secrets": ["<RSA_Encrypt_0>", "<RSA_Encrypt_1>", "..", "<RSA_Encrypt_N>"]
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"secrets_backup": ["<RSA_Encrypt_to_backup_key(...)", "..."],
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}
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```
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### Use an Unrestricted Decryption Transport Key (TK) for Secret Transport (server-side)
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Another option is to generate an asymmetric key-pair at device
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enrollment time (we shall call this the "transport key", or `TK`), and
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store:
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- the TK exported to the client device's TPM (i.e., the output of
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`TPM2_Duplicate()` called on that private key to export it to the
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client's TPM's EKpub), and
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- the ciphertext resulting from encrypting long-term secrets to that
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TK.
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At attestation time the server can send back these two values to the
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client, and then the client can `TPM2_Import()` and then `TPM2_Load()`
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the duplicated (exported) TK, then use it to `TPM2_RSA_Decrypt()` the
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encrypted long-term secrets.
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New secrets can be added at any time without interaction with the
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client.
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```JSON
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{
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"EKpub": "<EKpub>",
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"hostname": "<hostname>",
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"EKcert": "<EKcert in PEM, if available>",
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"previous_firmware_profile": "FWProfile0",
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"current_firmware_profiles": ["FWProfile1", "FWProfile2", "..."],
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"previous_operating_system_profiles": "OSProfile0",
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"current_operating_system_profiles": ["OSProfile1", "OSProfile2", "..."],
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"previous_PCRs": "<...>",
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"proposed_PCRs": "<...>",
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"ak_cert_template": "<AKCertTemplate>",
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"resetCount": "<resetCount value from last quote>",
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"secret store and transport fields":"vvvvvvvvvvvvvvvvvv",
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"TKdup": "<output of TPM2_Duplicate(EKpub, TK)>",
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"TKpub": "<TKpub in PEM>",
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"secrets": ["<RSA_Encrypt_0>", "<RSA_Encrypt_1>", "..", "<RSA_Encrypt_N>"]
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"secrets_backup": ["<RSA_Encrypt_to_backup_key(...)", "..."],
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}
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```
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### Store a Secret PCR Extension Value for Unsealing Data Objects
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The attestation server could store in plaintext a secret that it will
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returned encrypted to the client's EKpub vias `TPM2_MakeCredential()`,
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and which the client must use to extend a PCR (e.g., the debug PCR) to
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get that PCR into the state needed to unseal a persistent data object on
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the TPM.
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Because the sealed data object may itself be stored in cleartext in the
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TPM's NVRAM, and because an attacker might be able to decap a stolen
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client device's TPM and recover the TPM's NVRAM contents and seeds, the
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client might store an encrypted value in that sealed data object that
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the TPM does not have the keey to decrypt. The decryption key would be
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sent by the attestation server (possibly being the same secret as is
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extended into that PCR).
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```JSON
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{
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"EKpub": "<EKpub>",
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"hostname": "<hostname>",
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"EKcert": "<EKcert in PEM, if available>",
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"previous_firmware_profile": "FWProfile0",
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"current_firmware_profiles": ["FWProfile1", "FWProfile2", "..."],
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"previous_operating_system_profiles": "OSProfile0",
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"current_operating_system_profiles": ["OSProfile1", "OSProfile2", "..."],
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"previous_PCRs": "<...>",
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"proposed_PCRs": "<...>",
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"ak_cert_template": "<AKCertTemplate>",
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"resetCount": "<resetCount value from last quote>",
|
||||
|
||||
"secret store and transport fields":"vvvvvvvvvvvvvvvvvv",
|
||||
|
||||
"unseal_key": "<key>",
|
||||
"secrets_backup": ["<RSA_Encrypt_to_backup_key(...)", "..."],
|
||||
}
|
||||
```
|
||||
|
||||
### Store Secrets in Plaintext, Encrypt to EKpub Using `TPM2_MakeCredential()`
|
||||
|
||||
As the title says, one option is to store the secrets in plaintext and
|
||||
send them encrypted to the EKpub via
|
||||
[`TPM2_MakeCredential()`](/TPM-Commands/TPM2_MakeCredential.md).
|
||||
Because [`TPM2_MakeCredential()`](/TPM-Commands/TPM2_MakeCredential.md)
|
||||
encrypts only a small secret, it goes without saying that that secret
|
||||
would be a one-time use symmetric encryption key that would be used to
|
||||
encrypt the actual secrets.
|
||||
|
||||
This is, naturally, the least desirable option.
|
||||
|
||||
```JSON
|
||||
{
|
||||
"EKpub": "<EKpub>",
|
||||
"hostname": "<hostname>",
|
||||
"EKcert": "<EKcert in PEM, if available>",
|
||||
"previous_firmware_profile": "FWProfile0",
|
||||
"current_firmware_profiles": ["FWProfile1", "FWProfile2", "..."],
|
||||
"previous_operating_system_profiles": "OSProfile0",
|
||||
"current_operating_system_profiles": ["OSProfile1", "OSProfile2", "..."],
|
||||
"previous_PCRs": "<...>",
|
||||
"proposed_PCRs": "<...>",
|
||||
"ak_cert_template": "<AKCertTemplate>",
|
||||
"resetCount": "<resetCount value from last quote>",
|
||||
|
||||
"secret store and transport fields":"vvvvvvvvvvvvvvvvvv",
|
||||
|
||||
"secrets": ["<secret_0>", "<secret_1>", "<secret_N>"]
|
||||
}
|
||||
```
|
||||
|
||||
# Security Considerations
|
||||
|
||||
TBD
|
||||
|
||||
# References
|
||||
|
||||
|
|
139
Enrollment/README.md
Normal file
139
Enrollment/README.md
Normal file
|
@ -0,0 +1,139 @@
|
|||
# Device Enrollment
|
||||
|
||||
Device Enrollment is the act of registering a device -anything from an
|
||||
IoT to a server- and creating the state that will be referenced in
|
||||
future [attestations](/Attestation/README.md) from that device.
|
||||
|
||||
This can be as simple as sending the device's endorsement key
|
||||
certificate (EKcert) to a registration server (possibly authenticating
|
||||
to that server using some administrator user's credentials), to a more
|
||||
complex protocol similar to [attestation](/Attestation/README.md).
|
||||
|
||||
## Online Enrollment
|
||||
|
||||
Online enrollment means that the device to be enrolled interacts with an
|
||||
enrollment service over a network.
|
||||
|
||||
## Off-line Enrollment
|
||||
|
||||
Off-line enrollment means that the device to be enrolled *does not*
|
||||
interact with an enrollment service.
|
||||
|
||||
For example, one might scan an endorsement key (EK) public key or
|
||||
certificate from a QR code on a shipment manifest and then enroll the
|
||||
device using only that information.
|
||||
|
||||
# Server-Side State to Create during Enrollment
|
||||
|
||||
- device name <-> EKpub binding
|
||||
- enrolling user/admin
|
||||
- that the device has a valid TPM (i.e., the EKcert validates to a
|
||||
trusted TPM vendor's trust anchor)
|
||||
- initial root of trust measurement (RTM)
|
||||
- backup, secret recovery keys
|
||||
- encrypted secrets to send to the device
|
||||
|
||||
# Client-side State to Create during Enrollment
|
||||
|
||||
- encrypted filesystems?
|
||||
- device credentials? (e.g., TLS server certificates, Kerberos keys ["keytabs"], etc.)
|
||||
|
||||
# Secrets Transport
|
||||
|
||||
Every time an enrolled device reboots, or possibly more often, it may
|
||||
have to connect to an attestation server to obtain secrets from it that
|
||||
the device needs in order to proceed. For example, filesystem
|
||||
decryption keys, general network access, device authentication
|
||||
credentials, etc.
|
||||
|
||||
See [attestation](/Attestation/README.md) for details of how to
|
||||
transport secrets onto an enrolled device post-enrollment.
|
||||
|
||||
# Enrollment Semantics
|
||||
|
||||
- online vs. off-line
|
||||
|
||||
- client device trust semantics:
|
||||
- bind device name and EKpub on first use ("BOFU")?
|
||||
- enroll into inventory and then allow authorized users to bind a
|
||||
device name to an EKpub on a first-come-first-served basis?
|
||||
|
||||
- enrollment server trust semantics:
|
||||
- trust on first use (TOFU) (i.e., trust the first enrollment server
|
||||
found)
|
||||
- pre-install a trust anchor on the client device
|
||||
- use a user/admin credential on the device to establish trust on
|
||||
the server (e.g., intrinsically to how user authentication works,
|
||||
or having the user review and approve the server's credentials)
|
||||
|
||||
# Threat Models
|
||||
|
||||
Threats:
|
||||
|
||||
- enrollment server impersonation
|
||||
- enrollment of rogue devices
|
||||
- eavesdroppers
|
||||
- DoS
|
||||
|
||||
A typical enrollment protocol for servers in datacenters may well not
|
||||
bother protecting against all of the above.
|
||||
|
||||
A typical enrollment protocol for IoTs in a home network also may well
|
||||
not bother protecting against any of the above.
|
||||
|
||||
Enrollment protocols for personal devices must protect against all the
|
||||
listed threats except DoS attacks.
|
||||
|
||||
# Enrollment Protocols
|
||||
|
||||
## Trivial Enrollment Protocols
|
||||
|
||||
The simplest enrollment protocols just have the client device send its
|
||||
EKcert to the enrollment server. The enrollment server may have a user
|
||||
associate enrolled devices with device IDs (e.g., hostnames), and the
|
||||
device's enrollment is complete.
|
||||
|
||||
## Enrollment Protocols with Proof of Possession and Attestation
|
||||
|
||||
A more complex enrollment protocol would have the device attest to
|
||||
possession of the EK whose EKpub is certified by its EKcert, and might
|
||||
as well also perform attestation of other things, such as RTM.
|
||||
|
||||
An enrollment protocol with proof of possession might look a lot like
|
||||
the [two round trip attestation
|
||||
protocol](/Attestation/README.md#two-round-trip-stateless-attestation-protocol-patterns),
|
||||
with the addition of `enrollment_data` in the last message from the
|
||||
client to the server (server authentication not shown):
|
||||
|
||||
```
|
||||
CS0: [ID], EKpub, [EKcert], AKpub, PCRs, eventlog, timestamp,
|
||||
TPM2_Quote(AK, PCRs, extra_data)=Signed_AK({hash-of-PCRs, misc, extra_data})
|
||||
SC0: {TPM2_MakeCredential(EKpub, AKpub, session_key), ticket}
|
||||
CS1: {ticket, MAC_session_key(CS0), CS0, Encrypt_session_key(enrollment_data)}
|
||||
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
(new)
|
||||
SC1: Encrypt_session_key({AKcert, filesystem_keys, etc.})
|
||||
|
||||
<extra_data includes timestamp>
|
||||
```
|
||||
|
||||
where
|
||||
|
||||
```
|
||||
enrollment_data = { Encrypt_TK(secrets), [TKpub], [HK_pub] }
|
||||
|
||||
secrets = any secrets generated on the client side
|
||||
TKpub = public part of transport key for encrypting secrets to the
|
||||
client
|
||||
HKpub = public part of a host key for host authentication
|
||||
```
|
||||
|
||||
## Enrollment Protocols for Personal Devices
|
||||
|
||||
Enrollment of personal devices in their owners' personal device groups
|
||||
can be a lot like Bluetooth device pairing. Where such devices have
|
||||
TPMs then perhaps there is a role for the TPM to play in enrollment.
|
||||
|
||||
# Security Considerations
|
||||
|
||||
TBD
|
|
@ -348,10 +348,18 @@ used to authenticate the TPM's legitimacy. The EK's public key
|
|||
("EKpub") can be used to uniquely identify a TPM, and possibly link to
|
||||
the platform's, and even the platform's user(s)' identities.
|
||||
|
||||
The `TPM2_CreatePrimary()` and `TPM2_CreateLoaded()` commands create key
|
||||
objects deterministically from the hierarchy's seed and the "template"
|
||||
used to create the key (which includes a "unique" area that provides
|
||||
"entropy" to the key derivation function).
|
||||
The [`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) command creates
|
||||
primary key objects deterministically from the hierarchy's seed and the
|
||||
"template" used to create the key (which includes a "unique" area that
|
||||
provides "entropy" to the key derivation function).
|
||||
|
||||
The [`TPM2_Create()`](TPM2_Create.md) command creates a ordinary
|
||||
objects.
|
||||
|
||||
The [`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md) command can also
|
||||
create primary key objects deterministically from the hierarchy's seed
|
||||
and the "template" used to create the key (which includes a "unique"
|
||||
area that provides "entropy" to the key derivation function).
|
||||
|
||||
## Key Wrapping and Resource Management
|
||||
|
||||
|
|
49
TPM-Commands/TPM2_Create.md
Normal file
49
TPM-Commands/TPM2_Create.md
Normal file
|
@ -0,0 +1,49 @@
|
|||
# `TPM2_Create()`
|
||||
|
||||
This command creates an ordinary key object.
|
||||
|
||||
The created object can then be loaded with [`TPM2_Load()`](TPM2_Load.md).
|
||||
|
||||
To decide whether to use [`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md),
|
||||
`TPM2_Create()`, or [`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md)
|
||||
refer to table 28 in section 2.7 of the [TCG TPM Library part 1:
|
||||
Architecture](https://trustedcomputinggroup.org/wp-content/uploads/TCG_TPM2_r1p59_Part1_Architecture_pub.pdf).
|
||||
|
||||
If you need to `TPM2_CertifyCreation()` that a TPM created some object,
|
||||
you must use [`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
`TPM2_Create()`.
|
||||
|
||||
If you need to seal the object to a PCR selection, you must use
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
`TPM2_Create()`.
|
||||
|
||||
If you need to create a derived object, you must use
|
||||
[`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md).
|
||||
|
||||
If you need to create an ordinary object, use `TPM2_Create()` or
|
||||
[`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md).
|
||||
|
||||
If you need to create a primary object, use
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
[`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md).
|
||||
|
||||
## Inputs
|
||||
|
||||
- `TPMI_DH_OBJECT parentHandle`
|
||||
- `TPM2B_PUBLIC inPublic`
|
||||
- `TPM2B_DATA outsideInfo`
|
||||
- `TPML_PCR_SELECTION creationPCR`
|
||||
|
||||
## Outputs (success case)
|
||||
|
||||
- `TPM_HANDLE objectHandle`
|
||||
- `TPM2B_PRIVATE outPrivate`
|
||||
- `TPM2B_PUBLIC outPublic`
|
||||
- `TPM2B_CREATION_DATA creationData`
|
||||
- `TPM2B_DIGEST creationHash`
|
||||
- `TPMT_TK_CREATION creationTicket`
|
||||
|
||||
## References
|
||||
|
||||
- [TCG TPM Library part 3: Commands, section 12.1](https://trustedcomputinggroup.org/wp-content/uploads/TCG_TPM2_r1p59_Part3_Commands_pub.pdf)
|
||||
|
43
TPM-Commands/TPM2_CreateLoaded.md
Normal file
43
TPM-Commands/TPM2_CreateLoaded.md
Normal file
|
@ -0,0 +1,43 @@
|
|||
# `TPM2_CreateLoaded()`
|
||||
|
||||
This command creates a key object and loads it. The object can be a
|
||||
primary key, in which case `TPM2_CreateLoaded()` behaves just like
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md). Or the object can be
|
||||
`ordinary` or `derived`.
|
||||
|
||||
The created object can then be loaded with [`TPM2_Load()`](TPM2_Load.md).
|
||||
|
||||
To decide whether to use `TPM2_CreateLoaded()`,
|
||||
[`TPM2_Create()`](TPM2_Create.md), or
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) refer to table 28 in
|
||||
section 2.7 of the [TCG TPM Library part 1:
|
||||
Architecture](https://trustedcomputinggroup.org/wp-content/uploads/TCG_TPM2_r1p59_Part1_Architecture_pub.pdf).
|
||||
|
||||
If you need to `TPM2_CertifyCreation()` that a TPM created some object,
|
||||
you must use [`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
[`TPM2_Create()`](TPM2_Create.md).
|
||||
|
||||
If you need to seal the object to a PCR selection, you must use
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
[`TPM2_Create()`](TPM2_Create.md).
|
||||
|
||||
If you need to create a derived object, you must use
|
||||
`TPM2_CreateLoaded()`.
|
||||
|
||||
## Inputs
|
||||
|
||||
- `TPMI_DH_PARENT+ parentHandle`
|
||||
- `TPM2B_SENSITIVE_CREATE inSensitive`
|
||||
- `TPM2B_TEMPLATE inPublic`
|
||||
|
||||
## Outputs (success case)
|
||||
|
||||
- `TPM_HANDLE objectHandle`
|
||||
- `TPM2B_PRIVATE outPrivate` (optional)
|
||||
- `TPM2B_PUBLIC outPublic`
|
||||
- `TPM2B_NAME name`
|
||||
|
||||
## References
|
||||
|
||||
- [TCG TPM Library part 3: Commands, section 12.9](https://trustedcomputinggroup.org/wp-content/uploads/TCG_TPM2_r1p59_Part3_Commands_pub.pdf)
|
||||
|
41
TPM-Commands/TPM2_CreatePrimary.md
Normal file
41
TPM-Commands/TPM2_CreatePrimary.md
Normal file
|
@ -0,0 +1,41 @@
|
|||
# `TPM2_CreatePrimary()`
|
||||
|
||||
This command creates a primary key object.
|
||||
|
||||
The created object can then be loaded with [`TPM2_Load()`](TPM2_Load.md).
|
||||
|
||||
To decide whether to use [`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md),
|
||||
[`TPM2_Create()`](TPM2_Create.md), or
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) refer to table 28 in
|
||||
section 2.7 of the [TCG TPM Library part 1:
|
||||
Architecture](https://trustedcomputinggroup.org/wp-content/uploads/TCG_TPM2_r1p59_Part1_Architecture_pub.pdf).
|
||||
|
||||
If you need to `TPM2_CertifyCreation()` that a TPM created some object,
|
||||
you must use [`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
[`TPM2_Create()`](TPM2_Create.md).
|
||||
|
||||
If you need to seal the object to a PCR selection, you must use
|
||||
[`TPM2_CreatePrimary()`](TPM2_CreatePrimary.md) or
|
||||
[`TPM2_Create()`](TPM2_Create.md).
|
||||
|
||||
If you need to create a derived object, you must use
|
||||
[`TPM2_CreateLoaded()`](TPM2_CreateLoaded.md).
|
||||
|
||||
## Inputs
|
||||
|
||||
- `TPMI_RH_HIERARCHY+ primaryHandle`
|
||||
- `TPM2B_TEMPLATE inPublic`
|
||||
- `TPM2B_DATA outsideInfo`
|
||||
- `TPML_PCR_SELECTION creationPCR`
|
||||
|
||||
## Outputs (success case)
|
||||
|
||||
- `TPM_HANDLE objectHandle`
|
||||
- `TPM2B_CREATION_DATA creationData`
|
||||
- `TPM2B_DIGEST creationHash`
|
||||
- `TPMT_TK_CREATION creationTicket`
|
||||
- `TPM2B_NAME name`
|
||||
|
||||
## References
|
||||
|
||||
- [TCG TPM Library part 3: Commands, section 24.1](https://trustedcomputinggroup.org/wp-content/uploads/TCG_TPM2_r1p59_Part3_Commands_pub.pdf)
|
Loading…
Reference in a new issue