// Copyright (c) 2018, Google LLC All rights reserved. // // 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. package tpm2 import ( "crypto" "crypto/elliptic" "fmt" "strings" // Register the relevant hash implementations to prevent a runtime failure. _ "crypto/sha1" _ "crypto/sha256" _ "crypto/sha512" "github.com/google/go-tpm/tpmutil" ) var hashInfo = []struct { alg Algorithm hash crypto.Hash }{ {AlgSHA1, crypto.SHA1}, {AlgSHA256, crypto.SHA256}, {AlgSHA384, crypto.SHA384}, {AlgSHA512, crypto.SHA512}, {AlgSHA3_256, crypto.SHA3_256}, {AlgSHA3_384, crypto.SHA3_384}, {AlgSHA3_512, crypto.SHA3_512}, } // MAX_DIGEST_BUFFER is the maximum size of []byte request or response fields. // Typically used for chunking of big blobs of data (such as for hashing or // encryption). const maxDigestBuffer = 1024 // Algorithm represents a TPM_ALG_ID value. type Algorithm uint16 // HashToAlgorithm looks up the TPM2 algorithm corresponding to the provided crypto.Hash func HashToAlgorithm(hash crypto.Hash) (Algorithm, error) { for _, info := range hashInfo { if info.hash == hash { return info.alg, nil } } return AlgUnknown, fmt.Errorf("go hash algorithm #%d has no TPM2 algorithm", hash) } // IsNull returns true if a is AlgNull or zero (unset). func (a Algorithm) IsNull() bool { return a == AlgNull || a == AlgUnknown } // UsesCount returns true if a signature algorithm uses count value. func (a Algorithm) UsesCount() bool { return a == AlgECDAA } // UsesHash returns true if the algorithm requires the use of a hash. func (a Algorithm) UsesHash() bool { return a == AlgOAEP } // Hash returns a crypto.Hash based on the given TPM_ALG_ID. // An error is returned if the given algorithm is not a hash algorithm or is not available. func (a Algorithm) Hash() (crypto.Hash, error) { for _, info := range hashInfo { if info.alg == a { if !info.hash.Available() { return crypto.Hash(0), fmt.Errorf("go hash algorithm #%d not available", info.hash) } return info.hash, nil } } return crypto.Hash(0), fmt.Errorf("hash algorithm not supported: 0x%x", a) } func (a Algorithm) String() string { var s strings.Builder var err error switch a { case AlgUnknown: _, err = s.WriteString("AlgUnknown") case AlgRSA: _, err = s.WriteString("RSA") case AlgSHA1: _, err = s.WriteString("SHA1") case AlgHMAC: _, err = s.WriteString("HMAC") case AlgAES: _, err = s.WriteString("AES") case AlgKeyedHash: _, err = s.WriteString("KeyedHash") case AlgXOR: _, err = s.WriteString("XOR") case AlgSHA256: _, err = s.WriteString("SHA256") case AlgSHA384: _, err = s.WriteString("SHA384") case AlgSHA512: _, err = s.WriteString("SHA512") case AlgNull: _, err = s.WriteString("AlgNull") case AlgRSASSA: _, err = s.WriteString("RSASSA") case AlgRSAES: _, err = s.WriteString("RSAES") case AlgRSAPSS: _, err = s.WriteString("RSAPSS") case AlgOAEP: _, err = s.WriteString("OAEP") case AlgECDSA: _, err = s.WriteString("ECDSA") case AlgECDH: _, err = s.WriteString("ECDH") case AlgECDAA: _, err = s.WriteString("ECDAA") case AlgKDF2: _, err = s.WriteString("KDF2") case AlgECC: _, err = s.WriteString("ECC") case AlgSymCipher: _, err = s.WriteString("SymCipher") case AlgSHA3_256: _, err = s.WriteString("SHA3_256") case AlgSHA3_384: _, err = s.WriteString("SHA3_384") case AlgSHA3_512: _, err = s.WriteString("SHA3_512") case AlgCTR: _, err = s.WriteString("CTR") case AlgOFB: _, err = s.WriteString("OFB") case AlgCBC: _, err = s.WriteString("CBC") case AlgCFB: _, err = s.WriteString("CFB") case AlgECB: _, err = s.WriteString("ECB") default: return fmt.Sprintf("Alg?<%d>", int(a)) } if err != nil { return fmt.Sprintf("Writing to string builder failed: %v", err) } return s.String() } // Supported Algorithms. const ( AlgUnknown Algorithm = 0x0000 AlgRSA Algorithm = 0x0001 AlgSHA1 Algorithm = 0x0004 AlgHMAC Algorithm = 0x0005 AlgAES Algorithm = 0x0006 AlgKeyedHash Algorithm = 0x0008 AlgXOR Algorithm = 0x000A AlgSHA256 Algorithm = 0x000B AlgSHA384 Algorithm = 0x000C AlgSHA512 Algorithm = 0x000D AlgNull Algorithm = 0x0010 AlgRSASSA Algorithm = 0x0014 AlgRSAES Algorithm = 0x0015 AlgRSAPSS Algorithm = 0x0016 AlgOAEP Algorithm = 0x0017 AlgECDSA Algorithm = 0x0018 AlgECDH Algorithm = 0x0019 AlgECDAA Algorithm = 0x001A AlgKDF2 Algorithm = 0x0021 AlgECC Algorithm = 0x0023 AlgSymCipher Algorithm = 0x0025 AlgSHA3_256 Algorithm = 0x0027 AlgSHA3_384 Algorithm = 0x0028 AlgSHA3_512 Algorithm = 0x0029 AlgCTR Algorithm = 0x0040 AlgOFB Algorithm = 0x0041 AlgCBC Algorithm = 0x0042 AlgCFB Algorithm = 0x0043 AlgECB Algorithm = 0x0044 ) // HandleType defines a type of handle. type HandleType uint8 // Supported handle types const ( HandleTypePCR HandleType = 0x00 HandleTypeNVIndex HandleType = 0x01 HandleTypeHMACSession HandleType = 0x02 HandleTypeLoadedSession HandleType = 0x02 HandleTypePolicySession HandleType = 0x03 HandleTypeSavedSession HandleType = 0x03 HandleTypePermanent HandleType = 0x40 HandleTypeTransient HandleType = 0x80 HandleTypePersistent HandleType = 0x81 ) // SessionType defines the type of session created in StartAuthSession. type SessionType uint8 // Supported session types. const ( SessionHMAC SessionType = 0x00 SessionPolicy SessionType = 0x01 SessionTrial SessionType = 0x03 ) // SessionAttributes represents an attribute of a session. type SessionAttributes byte // Session Attributes (Structures 8.4 TPMA_SESSION) const ( AttrContinueSession SessionAttributes = 1 << iota AttrAuditExclusive AttrAuditReset _ // bit 3 reserved _ // bit 4 reserved AttrDecrypt AttrEcrypt AttrAudit ) // EmptyAuth represents the empty authorization value. var EmptyAuth []byte // KeyProp is a bitmask used in Attributes field of key templates. Individual // flags should be OR-ed to form a full mask. type KeyProp uint32 // Key properties. const ( FlagFixedTPM KeyProp = 0x00000002 FlagStClear KeyProp = 0x00000004 FlagFixedParent KeyProp = 0x00000010 FlagSensitiveDataOrigin KeyProp = 0x00000020 FlagUserWithAuth KeyProp = 0x00000040 FlagAdminWithPolicy KeyProp = 0x00000080 FlagNoDA KeyProp = 0x00000400 FlagRestricted KeyProp = 0x00010000 FlagDecrypt KeyProp = 0x00020000 FlagSign KeyProp = 0x00040000 FlagSealDefault = FlagFixedTPM | FlagFixedParent FlagSignerDefault = FlagSign | FlagRestricted | FlagFixedTPM | FlagFixedParent | FlagSensitiveDataOrigin | FlagUserWithAuth FlagStorageDefault = FlagDecrypt | FlagRestricted | FlagFixedTPM | FlagFixedParent | FlagSensitiveDataOrigin | FlagUserWithAuth ) // TPMProp represents a Property Tag (TPM_PT) used with calls to GetCapability(CapabilityTPMProperties). type TPMProp uint32 // TPM Capability Properties, see TPM 2.0 Spec, Rev 1.38, Table 23. // Fixed TPM Properties (PT_FIXED) const ( FamilyIndicator TPMProp = 0x100 + iota SpecLevel SpecRevision SpecDayOfYear SpecYear Manufacturer VendorString1 VendorString2 VendorString3 VendorString4 VendorTPMType FirmwareVersion1 FirmwareVersion2 InputMaxBufferSize TransientObjectsMin PersistentObjectsMin LoadedObjectsMin ActiveSessionsMax PCRCount PCRSelectMin ContextGapMax _ // (PT_FIXED + 21) is skipped NVCountersMax NVIndexMax MemoryMethod ClockUpdate ContextHash ContextSym ContextSymSize OrderlyCount CommandMaxSize ResponseMaxSize DigestMaxSize ObjectContextMaxSize SessionContextMaxSize PSFamilyIndicator PSSpecLevel PSSpecRevision PSSpecDayOfYear PSSpecYear SplitSigningMax TotalCommands LibraryCommands VendorCommands NVMaxBufferSize TPMModes CapabilityMaxBufferSize ) // Variable TPM Properties (PT_VAR) const ( TPMAPermanent TPMProp = 0x200 + iota TPMAStartupClear HRNVIndex HRLoaded HRLoadedAvail HRActive HRActiveAvail HRTransientAvail CurrentPersistent AvailPersistent NVCounters NVCountersAvail AlgorithmSet LoadedCurves LockoutCounter MaxAuthFail LockoutInterval LockoutRecovery NVWriteRecovery AuditCounter0 AuditCounter1 ) // Allowed ranges of different kinds of Handles (TPM_HANDLE) // These constants have type TPMProp for backwards compatibility. const ( PCRFirst TPMProp = 0x00000000 HMACSessionFirst TPMProp = 0x02000000 LoadedSessionFirst TPMProp = 0x02000000 PolicySessionFirst TPMProp = 0x03000000 ActiveSessionFirst TPMProp = 0x03000000 TransientFirst TPMProp = 0x80000000 PersistentFirst TPMProp = 0x81000000 PersistentLast TPMProp = 0x81FFFFFF PlatformPersistent TPMProp = 0x81800000 NVIndexFirst TPMProp = 0x01000000 NVIndexLast TPMProp = 0x01FFFFFF PermanentFirst TPMProp = 0x40000000 PermanentLast TPMProp = 0x4000010F ) // Reserved Handles. const ( HandleOwner tpmutil.Handle = 0x40000001 + iota HandleRevoke HandleTransport HandleOperator HandleAdmin HandleEK HandleNull HandleUnassigned HandlePasswordSession HandleLockout HandleEndorsement HandlePlatform ) // Capability identifies some TPM property or state type. type Capability uint32 // TPM Capabilities. const ( CapabilityAlgs Capability = iota CapabilityHandles CapabilityCommands CapabilityPPCommands CapabilityAuditCommands CapabilityPCRs CapabilityTPMProperties CapabilityPCRProperties CapabilityECCCurves CapabilityAuthPolicies ) // TPM Structure Tags. Tags are used to disambiguate structures, similar to Alg // values: tag value defines what kind of data lives in a nested field. const ( TagNull tpmutil.Tag = 0x8000 TagNoSessions tpmutil.Tag = 0x8001 TagSessions tpmutil.Tag = 0x8002 TagAttestCertify tpmutil.Tag = 0x8017 TagAttestQuote tpmutil.Tag = 0x8018 TagAttestCreation tpmutil.Tag = 0x801a TagAuthSecret tpmutil.Tag = 0x8023 TagHashCheck tpmutil.Tag = 0x8024 TagAuthSigned tpmutil.Tag = 0x8025 ) // StartupType instructs the TPM on how to handle its state during Shutdown or // Startup. type StartupType uint16 // Startup types const ( StartupClear StartupType = iota StartupState ) // EllipticCurve identifies specific EC curves. type EllipticCurve uint16 // ECC curves supported by TPM 2.0 spec. const ( CurveNISTP192 = EllipticCurve(iota + 1) CurveNISTP224 CurveNISTP256 CurveNISTP384 CurveNISTP521 CurveBNP256 = EllipticCurve(iota + 10) CurveBNP638 CurveSM2P256 = EllipticCurve(0x0020) ) var toGoCurve = map[EllipticCurve]elliptic.Curve{ CurveNISTP224: elliptic.P224(), CurveNISTP256: elliptic.P256(), CurveNISTP384: elliptic.P384(), CurveNISTP521: elliptic.P521(), } // Supported TPM operations. const ( CmdNVUndefineSpaceSpecial tpmutil.Command = 0x0000011F CmdEvictControl tpmutil.Command = 0x00000120 CmdUndefineSpace tpmutil.Command = 0x00000122 CmdClear tpmutil.Command = 0x00000126 CmdHierarchyChangeAuth tpmutil.Command = 0x00000129 CmdDefineSpace tpmutil.Command = 0x0000012A CmdPCRAllocate tpmutil.Command = 0x0000012B CmdCreatePrimary tpmutil.Command = 0x00000131 CmdIncrementNVCounter tpmutil.Command = 0x00000134 CmdWriteNV tpmutil.Command = 0x00000137 CmdWriteLockNV tpmutil.Command = 0x00000138 CmdDictionaryAttackLockReset tpmutil.Command = 0x00000139 CmdDictionaryAttackParameters tpmutil.Command = 0x0000013A CmdPCREvent tpmutil.Command = 0x0000013C CmdPCRReset tpmutil.Command = 0x0000013D CmdSequenceComplete tpmutil.Command = 0x0000013E CmdStartup tpmutil.Command = 0x00000144 CmdShutdown tpmutil.Command = 0x00000145 CmdActivateCredential tpmutil.Command = 0x00000147 CmdCertify tpmutil.Command = 0x00000148 CmdCertifyCreation tpmutil.Command = 0x0000014A CmdReadNV tpmutil.Command = 0x0000014E CmdReadLockNV tpmutil.Command = 0x0000014F CmdPolicySecret tpmutil.Command = 0x00000151 CmdCreate tpmutil.Command = 0x00000153 CmdECDHZGen tpmutil.Command = 0x00000154 CmdImport tpmutil.Command = 0x00000156 CmdLoad tpmutil.Command = 0x00000157 CmdQuote tpmutil.Command = 0x00000158 CmdRSADecrypt tpmutil.Command = 0x00000159 CmdSequenceUpdate tpmutil.Command = 0x0000015C CmdSign tpmutil.Command = 0x0000015D CmdUnseal tpmutil.Command = 0x0000015E CmdPolicySigned tpmutil.Command = 0x00000160 CmdContextLoad tpmutil.Command = 0x00000161 CmdContextSave tpmutil.Command = 0x00000162 CmdECDHKeyGen tpmutil.Command = 0x00000163 CmdEncryptDecrypt tpmutil.Command = 0x00000164 CmdFlushContext tpmutil.Command = 0x00000165 CmdLoadExternal tpmutil.Command = 0x00000167 CmdMakeCredential tpmutil.Command = 0x00000168 CmdReadPublicNV tpmutil.Command = 0x00000169 CmdPolicyCommandCode tpmutil.Command = 0x0000016C CmdPolicyOr tpmutil.Command = 0x00000171 CmdReadPublic tpmutil.Command = 0x00000173 CmdRSAEncrypt tpmutil.Command = 0x00000174 CmdStartAuthSession tpmutil.Command = 0x00000176 CmdGetCapability tpmutil.Command = 0x0000017A CmdGetRandom tpmutil.Command = 0x0000017B CmdHash tpmutil.Command = 0x0000017D CmdPCRRead tpmutil.Command = 0x0000017E CmdPolicyPCR tpmutil.Command = 0x0000017F CmdReadClock tpmutil.Command = 0x00000181 CmdPCRExtend tpmutil.Command = 0x00000182 CmdEventSequenceComplete tpmutil.Command = 0x00000185 CmdHashSequenceStart tpmutil.Command = 0x00000186 CmdPolicyGetDigest tpmutil.Command = 0x00000189 CmdPolicyPassword tpmutil.Command = 0x0000018C CmdEncryptDecrypt2 tpmutil.Command = 0x00000193 ) // Regular TPM 2.0 devices use 24-bit mask (3 bytes) for PCR selection. const sizeOfPCRSelect = 3 const defaultRSAExponent = 1<<16 + 1 // NVAttr is a bitmask used in Attributes field of NV indexes. Individual // flags should be OR-ed to form a full mask. type NVAttr uint32 // NV Attributes const ( AttrPPWrite NVAttr = 0x00000001 AttrOwnerWrite NVAttr = 0x00000002 AttrAuthWrite NVAttr = 0x00000004 AttrPolicyWrite NVAttr = 0x00000008 AttrPolicyDelete NVAttr = 0x00000400 AttrWriteLocked NVAttr = 0x00000800 AttrWriteAll NVAttr = 0x00001000 AttrWriteDefine NVAttr = 0x00002000 AttrWriteSTClear NVAttr = 0x00004000 AttrGlobalLock NVAttr = 0x00008000 AttrPPRead NVAttr = 0x00010000 AttrOwnerRead NVAttr = 0x00020000 AttrAuthRead NVAttr = 0x00040000 AttrPolicyRead NVAttr = 0x00080000 AttrNoDA NVAttr = 0x02000000 AttrOrderly NVAttr = 0x04000000 AttrClearSTClear NVAttr = 0x08000000 AttrReadLocked NVAttr = 0x10000000 AttrWritten NVAttr = 0x20000000 AttrPlatformCreate NVAttr = 0x40000000 AttrReadSTClear NVAttr = 0x80000000 ) var permMap = map[NVAttr]string{ AttrPPWrite: "PPWrite", AttrOwnerWrite: "OwnerWrite", AttrAuthWrite: "AuthWrite", AttrPolicyWrite: "PolicyWrite", AttrPolicyDelete: "PolicyDelete", AttrWriteLocked: "WriteLocked", AttrWriteAll: "WriteAll", AttrWriteDefine: "WriteDefine", AttrWriteSTClear: "WriteSTClear", AttrGlobalLock: "GlobalLock", AttrPPRead: "PPRead", AttrOwnerRead: "OwnerRead", AttrAuthRead: "AuthRead", AttrPolicyRead: "PolicyRead", AttrNoDA: "No Do", AttrOrderly: "Oderly", AttrClearSTClear: "ClearSTClear", AttrReadLocked: "ReadLocked", AttrWritten: "Writte", AttrPlatformCreate: "PlatformCreate", AttrReadSTClear: "ReadSTClear", } // String returns a textual representation of the set of NVAttr func (p NVAttr) String() string { var retString strings.Builder for iterator, item := range permMap { if (p & iterator) != 0 { retString.WriteString(item + " + ") } } if retString.String() == "" { return "Permission/s not found" } return strings.TrimSuffix(retString.String(), " + ") }