COCOS-407 - Add support for Linux IMA (#429)

* Added a feature which enables users to fetch IMA measurements and verify them

* Added a feature which enables users to fetch IMA measurements and verify them

* fixed lint error

* fixed according to comments

* fixed according to comments

* fixed according to comments

* fixed according to comments

* final bug fix

pkg/attestation/vtpm/vtpm.go

@@ -33,6 +33,7 @@ const (
 	eventLog = "/sys/kernel/security/tpm0/binary_bios_measurements"
 	Nonce    = 32
 	PCR15    = 15
+	Hash1    = 20
 	Hash256  = 32
 	Hash384  = 48
 )
@@ -315,3 +316,30 @@ func calculatePCRTLSKey(pubKey []byte) ([]byte, []byte) {
 
 	return newPcr256[:], newPcr384[:]
 }
+
+func getPCRValue(index int, algorithm tpm2.Algorithm) ([]byte, error) {
+	rwc, err := OpenTpm()
+	if err != nil {
+		return nil, err
+	}
+	defer rwc.Close()
+
+	pcrValue, err := tpm2.ReadPCR(rwc, index, algorithm)
+	if err != nil {
+		return nil, err
+	}
+
+	return pcrValue, nil
+}
+
+func GetPCRSHA1Value(index int) ([]byte, error) {
+	return getPCRValue(index, tpm2.AlgSHA1)
+}
+
+func GetPCRSHA256Value(index int) ([]byte, error) {
+	return getPCRValue(index, tpm2.AlgSHA256)
+}
+
+func GetPCRSHA384Value(index int) ([]byte, error) {
+	return getPCRValue(index, tpm2.AlgSHA384)
+}

pkg/progressbar/progressbar.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/fatih/color"
 	"github.com/ultravioletrs/cocos/agent"
+	"github.com/ultravioletrs/cocos/pkg/attestation/vtpm"
 	"golang.org/x/term"
 )
 
@@ -338,6 +339,22 @@ func (p *ProgressBar) ReceiveResult(description string, totalSize int, stream ag
 	}, resultFile)
 }
 
+func (p *ProgressBar) ReceiveIMAMeasurements(description string, totalSize int, stream agent.AgentService_IMAMeasurementsClient, resultFile *os.File) ([]byte, error) {
+	pcr10 := make([]byte, vtpm.Hash1)
+	err := p.receiveStream(description, totalSize, func() ([]byte, error) {
+		response, err := stream.Recv()
+		if err != nil {
+			return nil, err
+		}
+
+		copy(pcr10, response.Pcr10[:20])
+
+		return response.File, nil
+	}, resultFile)
+
+	return pcr10, err
+}
+
 func (p *ProgressBar) ReceiveAttestation(description string, totalSize int, stream agent.AgentService_AttestationClient, attestationFile *os.File) error {
 	return p.receiveStream(description, totalSize, func() ([]byte, error) {
 		response, err := stream.Recv()

pkg/sdk/agent.go

@@ -27,15 +27,17 @@ type SDK interface {
 	Data(ctx context.Context, dataset *os.File, filename string, privKey any) error
 	Result(ctx context.Context, privKey any, resultFile *os.File) error
 	Attestation(ctx context.Context, reportData [size64]byte, nonce [size32]byte, attType int, attestationFile *os.File) error
+	IMAMeasurements(ctx context.Context, resultFile *os.File) ([]byte, error)
 }
 
 const (
-	size64                         = 64
-	size32                         = 32
-	algoProgressBarDescription     = "Uploading algorithm"
-	dataProgressBarDescription     = "Uploading data"
-	resultProgressDescription      = "Downloading result"
-	attestationProgressDescription = "Downloading attestation"
+	size64                             = 64
+	size32                             = 32
+	algoProgressBarDescription         = "Uploading algorithm"
+	dataProgressBarDescription         = "Uploading data"
+	resultProgressDescription          = "Downloading result"
+	attestationProgressDescription     = "Downloading attestation"
+	imaMeasurementsProgressDescription = "Downloading Linux IMA measurements"
 )
 
 type agentSDK struct {
@@ -186,3 +188,32 @@ func generateMetadata(userID string, privateKey crypto.PrivateKey) (metadata.MD,
 	kv[auth.SignatureMetadataKey] = base64.StdEncoding.EncodeToString(signature)
 	return metadata.New(kv), nil
 }
+
+func (sdk *agentSDK) IMAMeasurements(ctx context.Context, resultFile *os.File) ([]byte, error) {
+	request := &agent.IMAMeasurementsRequest{}
+
+	stream, err := sdk.client.IMAMeasurements(ctx, request)
+	if err != nil {
+		return nil, err
+	}
+
+	incomingmd, err := stream.Header()
+	if err != nil {
+		return nil, err
+	}
+
+	fileSizeStr := incomingmd.Get(grpc.FileSizeKey)
+
+	if len(fileSizeStr) == 0 {
+		fileSizeStr = append(fileSizeStr, "0")
+	}
+
+	fileSize, err := strconv.Atoi(fileSizeStr[0])
+	if err != nil {
+		return nil, err
+	}
+
+	pb := progressbar.New(true)
+
+	return pb.ReceiveIMAMeasurements(imaMeasurementsProgressDescription, fileSize, stream, resultFile)
+}

pkg/sdk/mocks/sdk.go

@@ -173,6 +173,65 @@ func (_c *SDK_Data_Call) RunAndReturn(run func(context.Context, *os.File, string
 	return _c
 }
 
+// IMAMeasurements provides a mock function with given fields: ctx, resultFile
+func (_m *SDK) IMAMeasurements(ctx context.Context, resultFile *os.File) ([]byte, error) {
+	ret := _m.Called(ctx, resultFile)
+
+	if len(ret) == 0 {
+		panic("no return value specified for IMAMeasurements")
+	}
+
+	var r0 []byte
+	var r1 error
+	if rf, ok := ret.Get(0).(func(context.Context, *os.File) ([]byte, error)); ok {
+		return rf(ctx, resultFile)
+	}
+	if rf, ok := ret.Get(0).(func(context.Context, *os.File) []byte); ok {
+		r0 = rf(ctx, resultFile)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).([]byte)
+		}
+	}
+
+	if rf, ok := ret.Get(1).(func(context.Context, *os.File) error); ok {
+		r1 = rf(ctx, resultFile)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// SDK_IMAMeasurements_Call is a *mock.Call that shadows Run/Return methods with type explicit version for method 'IMAMeasurements'
+type SDK_IMAMeasurements_Call struct {
+	*mock.Call
+}
+
+// IMAMeasurements is a helper method to define mock.On call
+//   - ctx context.Context
+//   - resultFile *os.File
+func (_e *SDK_Expecter) IMAMeasurements(ctx interface{}, resultFile interface{}) *SDK_IMAMeasurements_Call {
+	return &SDK_IMAMeasurements_Call{Call: _e.mock.On("IMAMeasurements", ctx, resultFile)}
+}
+
+func (_c *SDK_IMAMeasurements_Call) Run(run func(ctx context.Context, resultFile *os.File)) *SDK_IMAMeasurements_Call {
+	_c.Call.Run(func(args mock.Arguments) {
+		run(args[0].(context.Context), args[1].(*os.File))
+	})
+	return _c
+}
+
+func (_c *SDK_IMAMeasurements_Call) Return(_a0 []byte, _a1 error) *SDK_IMAMeasurements_Call {
+	_c.Call.Return(_a0, _a1)
+	return _c
+}
+
+func (_c *SDK_IMAMeasurements_Call) RunAndReturn(run func(context.Context, *os.File) ([]byte, error)) *SDK_IMAMeasurements_Call {
+	_c.Call.Return(run)
+	return _c
+}
+
 // Result provides a mock function with given fields: ctx, privKey, resultFile
 func (_m *SDK) Result(ctx context.Context, privKey interface{}, resultFile *os.File) error {
 	ret := _m.Called(ctx, privKey, resultFile)