/// <summary>
/// Creates a *software* root key. The key will be random (not created from a seed). The key can be used
/// as the root of a software hierarchy that can be translated into a duplication blob ready for import into
/// a TPM. Depending on the type of key, the software root key can be a parent for other root keys that can
/// comprise a migration group. The caller should specify necessary key parameters in Public.
/// </summary>
/// <returns></returns>
public static TssObject CreateStorageParent(TpmPublic keyParameters, AuthValue authVal)
{
var newKey = new TssObject();
// Create a new asymmetric key from the supplied parameters
IPublicIdUnion publicId;
ISensitiveCompositeUnion sensitiveData = CreateSensitiveComposite(keyParameters, out publicId);
// fill in the public data
newKey.publicPart = keyParameters.Copy();
newKey.publicPart.unique = publicId;
// Create the associated symmetric key -
SymDefObject symDef = GetSymDef(keyParameters);
byte[] symmKey;
if (symDef.Algorithm != TpmAlgId.Null)
{
using (var symmCipher = SymmCipher.Create(symDef))
{
symmKey = symmCipher.KeyData;
}
}
else
{
symmKey = new byte[0];
}
// Fill in the fields for the symmetric private-part of the asymmetric key
var sens = new Sensitive(authVal.AuthVal, symmKey, sensitiveData);
newKey.sensitivePart = sens;
// And return the new key
return(newKey);
}
/// <summary>
/// Creates a Private area for this key so that it can be loaded into a TPM by
/// TPM2_Load() if the target TPM already has the storage key 'parent' loaded.
/// This function lets an application to create key hierarchies in software
/// that can be loaded into a TPM once the parent has been TPM2_Import'ed.
/// TPM2_Import() supports plaintext import. To get this sort of import blob,
/// set 'parent' to null.
/// </summary>
/// <param name="parent"></param>
/// <returns></returns>
public TpmPrivate GetPrivate(TssObject parent)
{
SymDefObject symDef = GetSymDef(parent.Public);
// Figure out how many bits we will need from the KDF
byte[] parentSymSeed = parent.Sensitive.seedValue;
Transform(parentSymSeed);
byte[] iv = (symDef.Mode == TpmAlgId.Ecb) ? new byte[0]
: Globs.GetRandomBytes(SymCipher.GetBlockSize(symDef));
// The encryption key is calculated with a KDF
byte[] symKey = KDF.KDFa(parent.Public.nameAlg,
parentSymSeed,
"STORAGE",
GetName(),
new byte[0],
symDef.KeyBits);
Transform(symKey);
byte[] newPrivate = KeyWrapper.CreatePrivateFromSensitive(
symDef,
symKey,
iv,
Sensitive,
Public.nameAlg,
Public.GetName(),
parent.Public.nameAlg,
parent.Sensitive.seedValue,
TransformerCallback);
Transform(newPrivate);
return(new TpmPrivate(newPrivate));
}
/// <summary>
/// Creates a Private area for this key that will be loadable on a TPM though TPM2_Load() if the target TPM already has the parent
/// storage key "parent" loaded. This function lets applications create key-hierarchies in software that can be loaded into
/// a TPM once the parent has been "TPM2_Import'ed."
/// TPM2_Import() supports plaintext import. To get this sort of import blob set intendedParent
/// to null
/// </summary>
/// <param name="intendedParent"></param>
/// <returns></returns>
public TpmPrivate GetPrivate(TssObject intendedParent)
{
SymDefObject symDef = GetSymDef(intendedParent.publicPart);
// Figure out how many bits we will need from the KDF
byte[] parentSymValue = intendedParent.sensitivePart.seedValue;
byte[] iv = Globs.GetRandomBytes(SymmCipher.GetBlockSize(symDef));
// The encryption key is calculated with a KDF
byte[] symKey = KDF.KDFa(intendedParent.publicPart.nameAlg,
parentSymValue,
"STORAGE",
GetName(),
new byte[0],
symDef.KeyBits);
byte[] newPrivate = KeyWrapper.CreatePrivateFromSensitive(symDef,
symKey,
iv,
sensitivePart,
publicPart.nameAlg,
publicPart.GetName(),
intendedParent.publicPart.nameAlg,
intendedParent.sensitivePart.seedValue);
return(new TpmPrivate(newPrivate));
}
private static void Transform(byte[] x, TssObject.Transformer f)
{
if (f == null)
{
return;
}
f(x);
}
/// <summary>
/// Create activation blobs that can be passed to ActivateCredential. Two blobs are returned -
/// (a) - encryptedSecret - is the symmetric key cfb-symmetrically encrypted with an enveloping key
/// (b) credentialBlob (the return value of this function) - is the enveloping key OEAP (RSA) encrypted
/// by the public part of this key.
/// </summary>
/// <param name="secret"></param>
/// <param name="nameAlgId"></param>
/// <param name="nameOfKeyToBeActivated"></param>
/// <param name="encryptedSecret"></param>
/// <returns>CredentialBlob (</returns>
public byte[] CreateActivationCredentials(
byte[] secret,
TpmAlgId nameAlgId,
byte[] nameOfKeyToBeActivated,
out byte[] encryptedSecret)
{
byte[] seed, encSecret;
switch (type)
{
case TpmAlgId.Rsa:
// The seed should be the same size as the symmKey
seed = Globs.GetRandomBytes((CryptoLib.DigestSize(nameAlg) + 7) / 8);
encSecret = EncryptOaep(seed, ActivateEncodingParms);
break;
case TpmAlgId.Ecc:
EccPoint pubEphem;
seed = EcdhGetKeyExchangeKey(ActivateEncodingParms, nameAlg, out pubEphem);
encSecret = Marshaller.GetTpmRepresentation(pubEphem);
break;
default:
Globs.Throw <NotImplementedException>("CreateActivationCredentials: Unsupported algorithm");
encryptedSecret = new byte[0];
return(new byte[0]);
}
var cvx = new Tpm2bDigest(secret);
byte[] cvTpm2B = Marshaller.GetTpmRepresentation(cvx);
SymDefObject symDef = TssObject.GetSymDef(this);
byte[] symKey = KDF.KDFa(nameAlg, seed, "STORAGE", nameOfKeyToBeActivated, new byte[0], symDef.KeyBits);
byte[] encIdentity;
using (SymmCipher symm2 = SymmCipher.Create(symDef, symKey))
{
encIdentity = symm2.Encrypt(cvTpm2B);
}
var hmacKeyBits = CryptoLib.DigestSize(nameAlg);
byte[] hmacKey = KDF.KDFa(nameAlg, seed, "INTEGRITY", new byte[0], new byte[0], hmacKeyBits * 8);
byte[] outerHmac = CryptoLib.HmacData(nameAlg,
hmacKey,
Globs.Concatenate(encIdentity, nameOfKeyToBeActivated));
byte[] activationBlob = Globs.Concatenate(
Marshaller.ToTpm2B(outerHmac),
encIdentity);
encryptedSecret = encSecret;
return(activationBlob);
}
/// <summary>
/// Creates a *software* key. The key will be random (not created from
/// a seed). The key can be used as the root of a software hierarchy that
/// can be translated into a duplication blob ready for import into a TPM.
/// Depending on the type of key, the software root key can be a parent for
/// other root keys that can comprise a migration group. The caller should
/// specify necessary key parameters in Public.
///
/// Parameter keyData is used only with symmetric or HMAC keys. If non-null
/// on entry, it contains the key bytes supplied by the caller, otherwise the
/// key will be randomly generated. For asymmetric keys keyData must be null.
///
/// Parameter authVal specifies the authorization value associated with the key.
/// If it is null, then an random value will be used.
/// </summary>
/// <param name="pub"></param>
/// <param name="authVal"></param>
/// <param name="keyData"></param>
/// <returns></returns>
public static TssObject Create(TpmPublic pub,
AuthValue authVal = null,
byte[] keyData = null)
{
var newKey = new TssObject();
// Create a new key from the supplied parameters
IPublicIdUnion publicId;
var sensData = CreateSensitiveComposite(pub, ref keyData, out publicId);
var nameSize = CryptoLib.DigestSize(pub.nameAlg);
// Create the associated seed value
byte[] seed = Globs.GetRandomBytes(nameSize);
// Fill in the fields for the symmetric private-part of the asymmetric key
var sens = new Sensitive(authVal ?? AuthValue.FromRandom(nameSize),
seed, sensData);
newKey.Sensitive = sens;
newKey.Private = new TpmPrivate(sens.GetTpm2BRepresentation());
// fill in the public data
newKey.Public = pub.Copy();
if (pub.type == TpmAlgId.Keyedhash || pub.type == TpmAlgId.Symcipher)
{
byte[] unique = null;
if (pub.objectAttributes.HasFlag(ObjectAttr.Restricted | ObjectAttr.Decrypt))
{
unique = CryptoLib.Hmac(pub.nameAlg, seed, keyData);
}
else
{
unique = CryptoLib.HashData(pub.nameAlg, seed, keyData);
}
newKey.Public.unique = pub.type == TpmAlgId.Keyedhash
? new Tpm2bDigestKeyedhash(unique) as IPublicIdUnion
: new Tpm2bDigestSymcipher(unique);
}
else
{
newKey.Public.unique = publicId;
}
// And return the new key
return(newKey);
}
/// <summary>
/// Create an enveloped (encrypted and integrity protected) private area from a provided sensitive.
/// </summary>
/// <param name="iv"></param>
/// <param name="sens"></param>
/// <param name="nameHash"></param>
/// <param name="publicName"></param>
/// <param name="symWrappingAlg"></param>
/// <param name="symKey"></param>
/// <param name="parentNameAlg"></param>
/// <param name="parentSeed"></param>
/// <param name="f"></param>
/// <returns></returns>
public static byte[] CreatePrivateFromSensitive(
SymDefObject symWrappingAlg,
byte[] symKey,
byte[] iv,
Sensitive sens,
TpmAlgId nameHash,
byte[] publicName,
TpmAlgId parentNameAlg,
byte[] parentSeed,
TssObject.Transformer f = null)
{
// ReSharper disable once InconsistentNaming
byte[] tpm2bIv = Marshaller.ToTpm2B(iv);
Transform(tpm2bIv, f);
byte[] sensitive = sens.GetTpmRepresentation();
Transform(sensitive, f);
// ReSharper disable once InconsistentNaming
byte[] tpm2bSensitive = Marshaller.ToTpm2B(sensitive);
Transform(tpm2bSensitive, f);
byte[] encSensitive = SymmCipher.Encrypt(symWrappingAlg, symKey, iv, tpm2bSensitive);
Transform(encSensitive, f);
byte[] decSensitive = SymmCipher.Decrypt(symWrappingAlg, symKey, iv, encSensitive);
Debug.Assert(f != null || Globs.ArraysAreEqual(decSensitive, tpm2bSensitive));
uint hmacKeyBits = (uint)CryptoLib.DigestSize(parentNameAlg) * 8;
byte[] hmacKey = KDF.KDFa(parentNameAlg, parentSeed, "INTEGRITY", new byte[0], new byte[0], hmacKeyBits);
Transform(hmacKey, f);
byte[] dataToHmac = Marshaller.GetTpmRepresentation(tpm2bIv,
encSensitive,
publicName);
Transform(dataToHmac, f);
byte[] outerHmac = CryptoLib.HmacData(parentNameAlg, hmacKey, dataToHmac);
Transform(outerHmac, f);
byte[] priv = Marshaller.GetTpmRepresentation(Marshaller.ToTpm2B(outerHmac),
tpm2bIv,
encSensitive);
Transform(priv, f);
return priv;
}
/// <summary>
/// Creates a *software* root key. The key will be random (not created from a seed). The key can be used
/// as the root of a software hierarchy that can be translated into a duplication blob ready for import into
/// a TPM. Depending on the type of key, the software root key can be a parent for other root keys that can
/// comprise a migration group. The caller should specify necessary key parameters in Public.
/// </summary>
/// <returns></returns>
public static TssObject CreateStorageParent(TpmPublic keyParameters, AuthValue authVal)
{
var newKey = new TssObject();
// Create a new asymmetric key from the supplied parameters
IPublicIdUnion publicId;
ISensitiveCompositeUnion sensitiveData = CreateSensitiveComposite(keyParameters, out publicId);
// fill in the public data
newKey.publicPart = keyParameters.Copy();
newKey.publicPart.unique = publicId;
// Create the associated symmetric key
byte[] symmKey = Globs.GetRandomBytes(CryptoLib.DigestSize(keyParameters.nameAlg));
// Fill in the fields for the symmetric private-part of the asymmetric key
var sens = new Sensitive(authVal.AuthVal, symmKey, sensitiveData);
newKey.sensitivePart = sens;
// And return the new key
return(newKey);
}
/// <summary>
/// Extract and return the SymDefObject that describes the symmetric
/// algorithm used for key protection in storage keys.
/// </summary>
/// <returns></returns>
public SymDefObject GetSymDef()
{
return(TssObject.GetSymDef(Public));
}
/// <summary>
/// Create activation blobs that can be passed to ActivateCredential. Two
/// blobs are returned:
/// 1) encryptedSecret - symmetric key cfb-symmetrically encrypted with the
/// enveloping key;
/// 2) credentialBlob - the enveloping key OEAP (RSA) encrypted by the public
/// part of this key. This is the return value of this
/// function
/// </summary>
/// <param name="secret"></param>
/// <param name="nameOfKeyToBeActivated"></param>
/// <param name="encryptedSecret"></param>
/// <returns>CredentialBlob (</returns>
public IdObject CreateActivationCredentials(byte[] secret,
byte[] nameOfKeyToBeActivated,
out byte[] encryptedSecret)
{
byte[] seed, encSecret;
switch (type)
{
case TpmAlgId.Rsa:
// The seed should be the same size as the name algorithmdigest
seed = Globs.GetRandomBytes(CryptoLib.DigestSize(nameAlg));
encSecret = EncryptOaep(seed, ActivateEncodingParms);
break;
case TpmAlgId.Ecc:
EccPoint ephemPubPt;
seed = EcdhGetKeyExchangeKey(ActivateEncodingParms, out ephemPubPt);
encSecret = Marshaller.GetTpmRepresentation(ephemPubPt);
break;
default:
Globs.Throw <NotImplementedException>(
"CreateActivationCredentials: Unsupported algorithm");
encryptedSecret = new byte[0];
return(null);
}
Transform(seed);
Transform(encSecret);
var cvx = new Tpm2bDigest(secret);
byte[] cvTpm2B = Marshaller.GetTpmRepresentation(cvx);
Transform(cvTpm2B);
SymDefObject symDef = TssObject.GetSymDef(this);
byte[] symKey = KDF.KDFa(nameAlg, seed, "STORAGE",
nameOfKeyToBeActivated, new byte[0], symDef.KeyBits);
Transform(symKey);
byte[] encIdentity;
// TPM only uses CFB mode in its command implementations
var sd = symDef.Copy();
sd.Mode = TpmAlgId.Cfb;
using (var sym = SymCipher.Create(sd, symKey))
{
// Not all keys specs are supported by SW crypto
if (sym == null)
{
encryptedSecret = null;
return(null);
}
encIdentity = sym.Encrypt(cvTpm2B);
}
Transform(encIdentity);
var hmacKeyBits = CryptoLib.DigestSize(nameAlg);
byte[] hmacKey = KDF.KDFa(nameAlg, seed, "INTEGRITY",
new byte[0], new byte[0], hmacKeyBits * 8);
Transform(hmacKey);
byte[] outerHmac = CryptoLib.Hmac(nameAlg, hmacKey,
Globs.Concatenate(encIdentity, nameOfKeyToBeActivated));
Transform(outerHmac);
encryptedSecret = encSecret;
return(new IdObject(outerHmac, encIdentity));
}
/// <summary>
/// Creates a Private area for this key that will be loadable on a TPM though TPM2_Load() if the target TPM already has the parent
/// storage key "parent" loaded. This function lets applications create key-hierarchies in software that can be loaded into
/// a TPM once the parent has been "TPM2_Import'ed."
/// TPM2_Import() supports plaintext import. To get this sort of import blob set intendedParent
/// to null
/// </summary>
/// <param name="intendedParent"></param>
/// <returns></returns>
public TpmPrivate GetPrivate(TssObject intendedParent)
{
SymDefObject symDef = GetSymDef(intendedParent.publicPart);
// Figure out how many bits we will need from the KDF
byte[] parentSymValue = intendedParent.sensitivePart.seedValue;
Transform(parentSymValue);
byte[] iv = Globs.GetRandomBytes(SymmCipher.GetBlockSize(symDef));
// The encryption key is calculated with a KDF
byte[] symKey = KDF.KDFa(intendedParent.publicPart.nameAlg,
parentSymValue,
"STORAGE",
GetName(),
new byte[0],
symDef.KeyBits);
Transform(symKey);
byte[] newPrivate = KeyWrapper.CreatePrivateFromSensitive(symDef,
symKey,
iv,
sensitivePart,
publicPart.nameAlg,
publicPart.GetName(),
intendedParent.publicPart.nameAlg,
intendedParent.sensitivePart.seedValue,
TransformerCallback);
Transform(newPrivate);
return new TpmPrivate(newPrivate);
}
/// <summary>
/// Creates a *software* root key. The key will be random (not created from a seed). The key can be used
/// as the root of a software hierarchy that can be translated into a duplication blob ready for import into
/// a TPM. Depending on the type of key, the software root key can be a parent for other root keys that can
/// comprise a migration group. The caller should specify necessary key parameters in Public.
/// </summary>
/// <returns></returns>
public static TssObject CreateStorageParent(TpmPublic keyParameters, AuthValue authVal)
{
var newKey = new TssObject();
// Create a new asymmetric key from the supplied parameters
IPublicIdUnion publicId;
ISensitiveCompositeUnion sensitiveData = CreateSensitiveComposite(keyParameters, out publicId);
// fill in the public data
newKey.publicPart = keyParameters.Copy();
newKey.publicPart.unique = publicId;
// Create the associated symmetric key -
SymDefObject symDef = GetSymDef(keyParameters);
byte[] symmKey;
if (symDef.Algorithm != TpmAlgId.Null)
{
using (var symmCipher = SymmCipher.Create(symDef))
{
symmKey = symmCipher.KeyData;
}
}
else
{
symmKey = new byte[0];
}
// Fill in the fields for the symmetric private-part of the asymmetric key
var sens = new Sensitive(authVal.AuthVal, symmKey, sensitiveData);
newKey.sensitivePart = sens;
// And return the new key
return newKey;
}
public TssObject(TssObject the_TssObject)
{
if((Object) the_TssObject == null ) throw new ArgumentException(Globs.GetResourceString("parmError"));
publicPart = the_TssObject.publicPart;
sensitivePart = the_TssObject.sensitivePart;
privatePart = the_TssObject.privatePart;
}
/// <summary>
/// Creates a *software* root key. The key will be random (not created from a seed). The key can be used
/// as the root of a software hierarchy that can be translated into a duplication blob ready for import into
/// a TPM. Depending on the type of key, the software root key can be a parent for other root keys that can
/// comprise a migration group. The caller should specify necessary key parameters in Public.
/// </summary>
/// <returns></returns>
public static TssObject CreateStorageParent(TpmPublic keyParameters, AuthValue authVal)
{
var newKey = new TssObject();
// Create a new asymmetric key from the supplied parameters
IPublicIdUnion publicId;
ISensitiveCompositeUnion sensitiveData = CreateSensitiveComposite(keyParameters, out publicId);
// fill in the public data
newKey.publicPart = keyParameters.Copy();
newKey.publicPart.unique = publicId;
// Create the associated symmetric key
byte[] symmKey = Globs.GetRandomBytes(CryptoLib.DigestSize(keyParameters.nameAlg));
// Fill in the fields for the symmetric private-part of the asymmetric key
var sens = new Sensitive(authVal.AuthVal, symmKey, sensitiveData);
newKey.sensitivePart = sens;
// And return the new key
return newKey;
}
