syntax = "proto2";

option go_package = ".;widevine";

// from x86 (partial), most of it from the ARM version:
message ClientIdentification {
    enum TokenType {
        KEYBOX = 0;
        DEVICE_CERTIFICATE = 1;
        REMOTE_ATTESTATION_CERTIFICATE = 2;
    }
    message NameValue {
        required string Name = 1;
        required string Value = 2;
    }
    message ClientCapabilities {
        enum HdcpVersion {
            HDCP_NONE = 0;
            HDCP_V1 = 1;
            HDCP_V2 = 2;
            HDCP_V2_1 = 3;
            HDCP_V2_2 = 4;
        }
        optional uint32 ClientToken = 1;
        optional uint32 SessionToken = 2;
        optional uint32 VideoResolutionConstraints = 3;
        optional HdcpVersion MaxHdcpVersion = 4;
        optional uint32 OemCryptoApiVersion = 5;
    }
    required TokenType Type = 1;
    //optional bytes Token = 2; // by default the client treats this as blob, but it's usually a DeviceCertificate, so for usefulness sake, I'm replacing it with this one:
    optional SignedDeviceCertificate Token = 2; // use this when parsing, "bytes" when building a client id blob
    repeated NameValue ClientInfo = 3;
    optional bytes ProviderClientToken = 4;
    optional uint32 LicenseCounter = 5;
    optional ClientCapabilities _ClientCapabilities = 6; // how should we deal with duped names? will have to look at proto docs later
    optional FileHashes _FileHashes = 7; // vmp blob goes here
}

message DeviceCertificate {
    enum CertificateType {
        ROOT = 0;
        INTERMEDIATE = 1;
        USER_DEVICE = 2;
        SERVICE = 3;
    }
    required CertificateType Type = 1; // the compiled code reused this as ProvisionedDeviceInfo.WvSecurityLevel, however that is incorrect (compiler aliased it as they're both identical as a structure)
    optional bytes SerialNumber = 2;
    optional uint32 CreationTimeSeconds = 3;
    optional bytes PublicKey = 4;
    optional uint32 SystemId = 5;
    optional uint32 TestDeviceDeprecated = 6; // is it bool or int?
    optional bytes ServiceId = 7; // service URL for service certificates
}

// missing some references,
message DeviceCertificateStatus {
    enum CertificateStatus {
        VALID = 0;
        REVOKED = 1;
    }
    optional bytes SerialNumber = 1;
    optional CertificateStatus Status = 2;
    optional ProvisionedDeviceInfo DeviceInfo = 4; // where is 3? is it deprecated?
}

message DeviceCertificateStatusList {
    optional uint32 CreationTimeSeconds = 1;
    repeated DeviceCertificateStatus CertificateStatus = 2;
}

message EncryptedClientIdentification {
    required string ServiceId = 1;
    optional bytes ServiceCertificateSerialNumber = 2;
    required bytes EncryptedClientId = 3;
    required bytes EncryptedClientIdIv = 4;
    required bytes EncryptedPrivacyKey = 5;
}

// todo: fill (for this top-level type, it might be impossible/difficult)
enum LicenseType {
    ZERO = 0;
    DEFAULT = 1; // 1 is STREAMING/temporary license; on recent versions may go up to 3 (latest x86); it might be persist/don't persist type, unconfirmed
    OFFLINE = 2;
}

// todo: fill (for this top-level type, it might be impossible/difficult)
// this is just a guess because these globals got lost, but really, do we need more?
enum ProtocolVersion {
    CURRENT = 21; // don't have symbols for this
}


message LicenseIdentification {
    optional bytes RequestId = 1;
    optional bytes SessionId = 2;
    optional bytes PurchaseId = 3;
    optional LicenseType Type = 4;
    optional uint32 Version = 5;
    optional bytes ProviderSessionToken = 6;
}


message License {
    message Policy {
        optional bool CanPlay = 1; // changed from uint32 to bool
        optional bool CanPersist = 2;
        optional bool CanRenew = 3;
        optional uint32 RentalDurationSeconds = 4;
        optional uint32 PlaybackDurationSeconds = 5;
        optional uint32 LicenseDurationSeconds = 6;
        optional uint32 RenewalRecoveryDurationSeconds = 7;
        optional string RenewalServerUrl = 8;
        optional uint32 RenewalDelaySeconds = 9;
        optional uint32 RenewalRetryIntervalSeconds = 10;
        optional bool RenewWithUsage = 11; // was uint32
    }
    message KeyContainer {
        enum KeyType {
            SIGNING = 1;
            CONTENT = 2;
            KEY_CONTROL = 3;
            OPERATOR_SESSION = 4;
        }
        enum SecurityLevel {
            SW_SECURE_CRYPTO = 1;
            SW_SECURE_DECODE = 2;
            HW_SECURE_CRYPTO = 3;
            HW_SECURE_DECODE = 4;
            HW_SECURE_ALL = 5;
        }
        message OutputProtection {
            enum CGMS {
                COPY_FREE = 0;
                COPY_ONCE = 2;
                COPY_NEVER = 3;
                CGMS_NONE = 0x2A; // PC default!
            }
            optional ClientIdentification.ClientCapabilities.HdcpVersion Hdcp = 1; // it's most likely a copy of Hdcp version available here, but compiler optimized it away
            optional CGMS CgmsFlags = 2;
        }
        message KeyControl {
            required bytes KeyControlBlock = 1; // what is this?
            required bytes Iv = 2;
        }
        message OperatorSessionKeyPermissions {
            optional uint32 AllowEncrypt = 1;
            optional uint32 AllowDecrypt = 2;
            optional uint32 AllowSign = 3;
            optional uint32 AllowSignatureVerify = 4;
        }
        message VideoResolutionConstraint {
            optional uint32 MinResolutionPixels = 1;
            optional uint32 MaxResolutionPixels = 2;
            optional OutputProtection RequiredProtection = 3;
        }
        optional bytes Id = 1;
        optional bytes Iv = 2;
        optional bytes Key = 3;
        optional KeyType Type = 4;
        optional SecurityLevel Level = 5;
        optional OutputProtection RequiredProtection = 6;
        optional OutputProtection RequestedProtection = 7;
        optional KeyControl _KeyControl = 8; // duped names, etc
        optional OperatorSessionKeyPermissions _OperatorSessionKeyPermissions = 9; // duped names, etc
        repeated VideoResolutionConstraint VideoResolutionConstraints = 10;
    }
    optional LicenseIdentification Id = 1;
    optional Policy _Policy = 2; // duped names, etc
    repeated KeyContainer Key = 3;
    optional uint32 LicenseStartTime = 4;
    optional uint32 RemoteAttestationVerified = 5; // bool?
    optional bytes ProviderClientToken = 6;
    // there might be more, check with newer versions (I see field 7-8 in a lic)
    // this appeared in latest x86:
    optional uint32 ProtectionScheme = 7; // type unconfirmed fully, but it's likely as WidevineCencHeader describesit (fourcc)
}

message LicenseError {
    enum Error {
        INVALID_DEVICE_CERTIFICATE = 1;
        REVOKED_DEVICE_CERTIFICATE = 2;
        SERVICE_UNAVAILABLE = 3;
    }
    //LicenseRequest.RequestType ErrorCode; // clang mismatch
    optional Error ErrorCode = 1;
}

message LicenseRequest {
    message ContentIdentification {
        message CENC {
            //optional bytes Pssh = 1; // the client's definition is opaque, it doesn't care about the contents, but the PSSH has a clear definition that is understood and requested by the server, thus I'll replace it with:
            optional WidevineCencHeader Pssh = 1;
            optional LicenseType LicenseType = 2; // unfortunately the LicenseType symbols are not present, acceptable value seems to only be 1 (is this persist/don't persist? look into it!)
            optional bytes RequestId = 3;
        }
        message WebM {
            optional bytes Header = 1; // identical to CENC, aside from PSSH and the parent field number used
            optional LicenseType LicenseType = 2;
            optional bytes RequestId = 3;
        }
        message ExistingLicense {
            optional LicenseIdentification LicenseId = 1;
            optional uint32 SecondsSinceStarted = 2;
            optional uint32 SecondsSinceLastPlayed = 3;
            optional bytes SessionUsageTableEntry = 4; // interesting! try to figure out the connection between the usage table blob and KCB!
        }
        optional CENC CencId = 1;
        optional WebM WebmId = 2;
        optional ExistingLicense License = 3;
    }
    enum RequestType {
        NEW = 1;
        RENEWAL = 2;
        RELEASE = 3;
    }
    optional ClientIdentification ClientId = 1;
    optional ContentIdentification ContentId = 2;
    optional RequestType Type = 3;
    optional uint32 RequestTime = 4;
    optional bytes KeyControlNonceDeprecated = 5;
    optional ProtocolVersion ProtocolVersion = 6; // lacking symbols for this
    optional uint32 KeyControlNonce = 7;
    optional EncryptedClientIdentification EncryptedClientId = 8;
}

// raw pssh hack
message LicenseRequestRaw {
    message ContentIdentification {
        message CENC {
            optional bytes Pssh = 1; // the client's definition is opaque, it doesn't care about the contents, but the PSSH has a clear definition that is understood and requested by the server, thus I'll replace it with:
            //optional WidevineCencHeader Pssh = 1;
            optional LicenseType LicenseType = 2; // unfortunately the LicenseType symbols are not present, acceptable value seems to only be 1 (is this persist/don't persist? look into it!)
            optional bytes RequestId = 3;
        }
        message WebM {
            optional bytes Header = 1; // identical to CENC, aside from PSSH and the parent field number used
            optional LicenseType LicenseType = 2;
            optional bytes RequestId = 3;
        }
        message ExistingLicense {
            optional LicenseIdentification LicenseId = 1;
            optional uint32 SecondsSinceStarted = 2;
            optional uint32 SecondsSinceLastPlayed = 3;
            optional bytes SessionUsageTableEntry = 4; // interesting! try to figure out the connection between the usage table blob and KCB!
        }
        optional CENC CencId = 1;
        optional WebM WebmId = 2;
        optional ExistingLicense License = 3;
    }
    enum RequestType {
        NEW = 1;
        RENEWAL = 2;
        RELEASE = 3;
    }
    optional ClientIdentification ClientId = 1;
    optional ContentIdentification ContentId = 2;
    optional RequestType Type = 3;
    optional uint32 RequestTime = 4;
    optional bytes KeyControlNonceDeprecated = 5;
    optional ProtocolVersion ProtocolVersion = 6; // lacking symbols for this
    optional uint32 KeyControlNonce = 7;
    optional EncryptedClientIdentification EncryptedClientId = 8;
}


message ProvisionedDeviceInfo {
    enum WvSecurityLevel {
        LEVEL_UNSPECIFIED = 0;
        LEVEL_1 = 1;
        LEVEL_2 = 2;
        LEVEL_3 = 3;
    }
    optional uint32 SystemId = 1;
    optional string Soc = 2;
    optional string Manufacturer = 3;
    optional string Model = 4;
    optional string DeviceType = 5;
    optional uint32 ModelYear = 6;
    optional WvSecurityLevel SecurityLevel = 7;
    optional uint32 TestDevice = 8; // bool?
}


// todo: fill
message ProvisioningOptions {
}

// todo: fill
message ProvisioningRequest {
}

// todo: fill
message ProvisioningResponse {
}

message RemoteAttestation {
    optional EncryptedClientIdentification Certificate = 1;
    optional string Salt = 2;
    optional string Signature = 3;
}

// todo: fill
message SessionInit {
}

// todo: fill
message SessionState {
}

// todo: fill
message SignedCertificateStatusList {
}

message SignedDeviceCertificate {

    //optional bytes DeviceCertificate = 1; // again, they use a buffer where it's supposed to be a message, so we'll replace it with what it really is:
    optional DeviceCertificate _DeviceCertificate = 1; // how should we deal with duped names? will have to look at proto docs later
    optional bytes Signature = 2;
    optional SignedDeviceCertificate Signer = 3;
}


// todo: fill
message SignedProvisioningMessage {
}

// the root of all messages, from either server or client
message SignedMessage {
    enum MessageType {
        LICENSE_REQUEST = 1;
        LICENSE = 2;
        ERROR_RESPONSE = 3;
        SERVICE_CERTIFICATE_REQUEST = 4;
        SERVICE_CERTIFICATE = 5;
    }
    optional MessageType Type = 1; // has in incorrect overlap with License_KeyContainer_SecurityLevel
    optional bytes Msg = 2; // this has to be casted dynamically, to LicenseRequest, License or LicenseError (? unconfirmed), for Request, no other fields but Type need to be present
    // for SERVICE_CERTIFICATE, only Type and Msg are present, and it's just a DeviceCertificate with CertificateType set to SERVICE
    optional bytes Signature = 3; // might be different type of signatures (ex. RSA vs AES CMAC(??), unconfirmed for now)
    optional bytes SessionKey = 4; // often RSA wrapped for licenses
    optional RemoteAttestation RemoteAttestation = 5;
}



// This message is copied from google's docs, not reversed:
message WidevineCencHeader {
    enum Algorithm {
        UNENCRYPTED = 0;
        AESCTR = 1;
    };
    optional Algorithm algorithm = 1;
    repeated bytes key_id = 2;

    // Content provider name.
    optional string provider = 3;

    // A content identifier, specified by content provider.
    optional bytes content_id = 4;

    // Track type. Acceptable values are SD, HD and AUDIO. Used to
    // differentiate content keys used by an asset.
    optional string track_type_deprecated = 5;

    // The name of a registered policy to be used for this asset.
    optional string policy = 6;

    // Crypto period index, for media using key rotation.
    optional uint32 crypto_period_index = 7;

    // Optional protected context for group content. The grouped_license is a
    // serialized SignedMessage.
    optional bytes grouped_license = 8;

    // Protection scheme identifying the encryption algorithm.
    // Represented as one of the following 4CC values:
    // 'cenc' (AESCTR), 'cbc1' (AESCBC),
    // 'cens' (AESCTR subsample), 'cbcs' (AESCBC subsample).
    optional uint32 protection_scheme = 9;

    // Optional. For media using key rotation, this represents the duration
    // of each crypto period in seconds.
    optional uint32 crypto_period_seconds = 10;
}


// remove these when using it outside of protoc:

// from here on, it's just for testing, these messages don't exist in the binaries, I'm adding them to avoid detecting type programmatically
message SignedLicenseRequest {
    enum MessageType {
        LICENSE_REQUEST = 1;
        LICENSE = 2;
        ERROR_RESPONSE = 3;
        SERVICE_CERTIFICATE_REQUEST = 4;
        SERVICE_CERTIFICATE = 5;
    }
    optional MessageType Type = 1; // has in incorrect overlap with License_KeyContainer_SecurityLevel
    optional LicenseRequest Msg = 2; // this has to be casted dynamically, to LicenseRequest, License or LicenseError (? unconfirmed), for Request, no other fields but Type need to be present
    // for SERVICE_CERTIFICATE, only Type and Msg are present, and it's just a DeviceCertificate with CertificateType set to SERVICE
    optional bytes Signature = 3; // might be different type of signatures (ex. RSA vs AES CMAC(??), unconfirmed for now)
    optional bytes SessionKey = 4; // often RSA wrapped for licenses
    optional RemoteAttestation RemoteAttestation = 5;
}

// hack
message SignedLicenseRequestRaw {
    enum MessageType {
        LICENSE_REQUEST = 1;
        LICENSE = 2;
        ERROR_RESPONSE = 3;
        SERVICE_CERTIFICATE_REQUEST = 4;
        SERVICE_CERTIFICATE = 5;
    }
    optional MessageType Type = 1; // has in incorrect overlap with License_KeyContainer_SecurityLevel
    optional LicenseRequestRaw Msg = 2; // this has to be casted dynamically, to LicenseRequest, License or LicenseError (? unconfirmed), for Request, no other fields but Type need to be present
    // for SERVICE_CERTIFICATE, only Type and Msg are present, and it's just a DeviceCertificate with CertificateType set to SERVICE
    optional bytes Signature = 3; // might be different type of signatures (ex. RSA vs AES CMAC(??), unconfirmed for now)
    optional bytes SessionKey = 4; // often RSA wrapped for licenses
    optional RemoteAttestation RemoteAttestation = 5;
}


message SignedLicense {
    enum MessageType {
        LICENSE_REQUEST = 1;
        LICENSE = 2;
        ERROR_RESPONSE = 3;
        SERVICE_CERTIFICATE_REQUEST = 4;
        SERVICE_CERTIFICATE = 5;
    }
    optional MessageType Type = 1; // has in incorrect overlap with License_KeyContainer_SecurityLevel
    optional License Msg = 2; // this has to be casted dynamically, to LicenseRequest, License or LicenseError (? unconfirmed), for Request, no other fields but Type need to be present
    // for SERVICE_CERTIFICATE, only Type and Msg are present, and it's just a DeviceCertificate with CertificateType set to SERVICE
    optional bytes Signature = 3; // might be different type of signatures (ex. RSA vs AES CMAC(??), unconfirmed for now)
    optional bytes SessionKey = 4; // often RSA wrapped for licenses
    optional RemoteAttestation RemoteAttestation = 5;
}

message SignedServiceCertificate {
    enum MessageType {
        LICENSE_REQUEST = 1;
        LICENSE = 2;
        ERROR_RESPONSE = 3;
        SERVICE_CERTIFICATE_REQUEST = 4;
        SERVICE_CERTIFICATE = 5;
    }
    optional MessageType Type = 1; // has in incorrect overlap with License_KeyContainer_SecurityLevel
    optional SignedDeviceCertificate Msg = 2; // this has to be casted dynamically, to LicenseRequest, License or LicenseError (? unconfirmed), for Request, no other fields but Type need to be present
    // for SERVICE_CERTIFICATE, only Type and Msg are present, and it's just a DeviceCertificate with CertificateType set to SERVICE
    optional bytes Signature = 3; // might be different type of signatures (ex. RSA vs AES CMAC(??), unconfirmed for now)
    optional bytes SessionKey = 4; // often RSA wrapped for licenses
    optional RemoteAttestation RemoteAttestation = 5;
}

//vmp support
message FileHashes {
   message Signature {
     optional string filename = 1;
     optional bool test_signing = 2; //0 - release, 1 - testing
     optional bytes SHA512Hash = 3;
     optional bool main_exe = 4; //0 for dlls, 1 for exe, this is field 3 in file
     optional bytes signature = 5;
   }
   optional bytes signer = 1;
   repeated Signature signatures = 2;
}