From 0150fc5d50ccecbd22a48545c27ecdd429b8214f Mon Sep 17 00:00:00 2001
From: Cesar Ghali <cesarghali@users.noreply.github.com>
Date: Wed, 5 Sep 2018 15:15:42 -0700
Subject: [PATCH] credentials/alts: Move alts/core to alts/internal (#2292)

---
 credentials/alts/alts.go                      |   8 +-
 credentials/alts/alts_test.go                 |   2 +-
 .../{core => internal}/authinfo/authinfo.go   |   2 +-
 .../authinfo/authinfo_test.go                 |   2 +-
 credentials/alts/{core => internal}/common.go |   0
 .../alts/{core => internal}/conn/aeadrekey.go |   0
 .../{core => internal}/conn/aeadrekey_test.go |   0
 .../alts/{core => internal}/conn/aes128gcm.go |   2 +-
 .../{core => internal}/conn/aes128gcm_test.go |   2 +-
 .../{core => internal}/conn/aes128gcmrekey.go |   2 +-
 .../conn/aes128gcmrekey_test.go               |   2 +-
 .../alts/{core => internal}/conn/common.go    |   0
 .../alts/{core => internal}/conn/counter.go   |   2 +-
 .../{core => internal}/conn/counter_test.go   |   2 +-
 .../alts/{core => internal}/conn/record.go    |   2 +-
 .../{core => internal}/conn/record_test.go    |   2 +-
 .../handshaker/handshaker.go                  |  10 +-
 .../handshaker/handshaker_test.go             |   6 +-
 .../handshaker/service/service.go             |   0
 .../handshaker/service/service_test.go        |   0
 .../proto/grpc_gcp/altscontext.pb.go          |  53 +++---
 .../proto/grpc_gcp/handshaker.pb.go           | 172 +++++++++---------
 .../grpc_gcp/transport_security_common.pb.go  |  52 +++---
 .../alts/{core => internal}/regenerate.sh     |   0
 .../{core => internal}/testutil/testutil.go   |   2 +-
 credentials/alts/utils_test.go                |   2 +-
 26 files changed, 163 insertions(+), 164 deletions(-)
 rename credentials/alts/{core => internal}/authinfo/authinfo.go (97%)
 rename credentials/alts/{core => internal}/authinfo/authinfo_test.go (98%)
 rename credentials/alts/{core => internal}/common.go (100%)
 rename credentials/alts/{core => internal}/conn/aeadrekey.go (100%)
 rename credentials/alts/{core => internal}/conn/aeadrekey_test.go (100%)
 rename credentials/alts/{core => internal}/conn/aes128gcm.go (98%)
 rename credentials/alts/{core => internal}/conn/aes128gcm_test.go (99%)
 rename credentials/alts/{core => internal}/conn/aes128gcmrekey.go (98%)
 rename credentials/alts/{core => internal}/conn/aes128gcmrekey_test.go (98%)
 rename credentials/alts/{core => internal}/conn/common.go (100%)
 rename credentials/alts/{core => internal}/conn/counter.go (97%)
 rename credentials/alts/{core => internal}/conn/counter_test.go (98%)
 rename credentials/alts/{core => internal}/conn/record.go (99%)
 rename credentials/alts/{core => internal}/conn/record_test.go (99%)
 rename credentials/alts/{core => internal}/handshaker/handshaker.go (97%)
 rename credentials/alts/{core => internal}/handshaker/handshaker_test.go (97%)
 rename credentials/alts/{core => internal}/handshaker/service/service.go (100%)
 rename credentials/alts/{core => internal}/handshaker/service/service_test.go (100%)
 rename credentials/alts/{core => internal}/proto/grpc_gcp/altscontext.pb.go (63%)
 rename credentials/alts/{core => internal}/proto/grpc_gcp/handshaker.pb.go (83%)
 rename credentials/alts/{core => internal}/proto/grpc_gcp/transport_security_common.pb.go (71%)
 rename credentials/alts/{core => internal}/regenerate.sh (100%)
 rename credentials/alts/{core => internal}/testutil/testutil.go (98%)

diff --git a/credentials/alts/alts.go b/credentials/alts/alts.go
index 94005654..3bb00142 100644
--- a/credentials/alts/alts.go
+++ b/credentials/alts/alts.go
@@ -32,10 +32,10 @@ import (
 
 	"golang.org/x/net/context"
 	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/credentials/alts/core"
-	"google.golang.org/grpc/credentials/alts/core/handshaker"
-	"google.golang.org/grpc/credentials/alts/core/handshaker/service"
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+	core "google.golang.org/grpc/credentials/alts/internal"
+	"google.golang.org/grpc/credentials/alts/internal/handshaker"
+	"google.golang.org/grpc/credentials/alts/internal/handshaker/service"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 	"google.golang.org/grpc/grpclog"
 )
 
diff --git a/credentials/alts/alts_test.go b/credentials/alts/alts_test.go
index 6b041d99..43c7732c 100644
--- a/credentials/alts/alts_test.go
+++ b/credentials/alts/alts_test.go
@@ -23,7 +23,7 @@ import (
 	"testing"
 
 	"github.com/golang/protobuf/proto"
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 )
 
 func TestInfoServerName(t *testing.T) {
diff --git a/credentials/alts/core/authinfo/authinfo.go b/credentials/alts/internal/authinfo/authinfo.go
similarity index 97%
rename from credentials/alts/core/authinfo/authinfo.go
rename to credentials/alts/internal/authinfo/authinfo.go
index 2fe54b74..ed628dc7 100644
--- a/credentials/alts/core/authinfo/authinfo.go
+++ b/credentials/alts/internal/authinfo/authinfo.go
@@ -21,7 +21,7 @@ package authinfo
 
 import (
 	"google.golang.org/grpc/credentials"
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 )
 
 var _ credentials.AuthInfo = (*altsAuthInfo)(nil)
diff --git a/credentials/alts/core/authinfo/authinfo_test.go b/credentials/alts/internal/authinfo/authinfo_test.go
similarity index 98%
rename from credentials/alts/core/authinfo/authinfo_test.go
rename to credentials/alts/internal/authinfo/authinfo_test.go
index 635d8049..91d9ffef 100644
--- a/credentials/alts/core/authinfo/authinfo_test.go
+++ b/credentials/alts/internal/authinfo/authinfo_test.go
@@ -22,7 +22,7 @@ import (
 	"reflect"
 	"testing"
 
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 )
 
 const (
diff --git a/credentials/alts/core/common.go b/credentials/alts/internal/common.go
similarity index 100%
rename from credentials/alts/core/common.go
rename to credentials/alts/internal/common.go
diff --git a/credentials/alts/core/conn/aeadrekey.go b/credentials/alts/internal/conn/aeadrekey.go
similarity index 100%
rename from credentials/alts/core/conn/aeadrekey.go
rename to credentials/alts/internal/conn/aeadrekey.go
diff --git a/credentials/alts/core/conn/aeadrekey_test.go b/credentials/alts/internal/conn/aeadrekey_test.go
similarity index 100%
rename from credentials/alts/core/conn/aeadrekey_test.go
rename to credentials/alts/internal/conn/aeadrekey_test.go
diff --git a/credentials/alts/core/conn/aes128gcm.go b/credentials/alts/internal/conn/aes128gcm.go
similarity index 98%
rename from credentials/alts/core/conn/aes128gcm.go
rename to credentials/alts/internal/conn/aes128gcm.go
index 0c4fe339..6247bd3e 100644
--- a/credentials/alts/core/conn/aes128gcm.go
+++ b/credentials/alts/internal/conn/aes128gcm.go
@@ -22,7 +22,7 @@ import (
 	"crypto/aes"
 	"crypto/cipher"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 const (
diff --git a/credentials/alts/core/conn/aes128gcm_test.go b/credentials/alts/internal/conn/aes128gcm_test.go
similarity index 99%
rename from credentials/alts/core/conn/aes128gcm_test.go
rename to credentials/alts/internal/conn/aes128gcm_test.go
index c2fca4dd..4580bcac 100644
--- a/credentials/alts/core/conn/aes128gcm_test.go
+++ b/credentials/alts/internal/conn/aes128gcm_test.go
@@ -22,7 +22,7 @@ import (
 	"bytes"
 	"testing"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 // cryptoTestVector is struct for a GCM test vector
diff --git a/credentials/alts/core/conn/aes128gcmrekey.go b/credentials/alts/internal/conn/aes128gcmrekey.go
similarity index 98%
rename from credentials/alts/core/conn/aes128gcmrekey.go
rename to credentials/alts/internal/conn/aes128gcmrekey.go
index 4b5ecf40..a3cc0a11 100644
--- a/credentials/alts/core/conn/aes128gcmrekey.go
+++ b/credentials/alts/internal/conn/aes128gcmrekey.go
@@ -21,7 +21,7 @@ package conn
 import (
 	"crypto/cipher"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 const (
diff --git a/credentials/alts/core/conn/aes128gcmrekey_test.go b/credentials/alts/internal/conn/aes128gcmrekey_test.go
similarity index 98%
rename from credentials/alts/core/conn/aes128gcmrekey_test.go
rename to credentials/alts/internal/conn/aes128gcmrekey_test.go
index 9f31a0fa..6bfde3ca 100644
--- a/credentials/alts/core/conn/aes128gcmrekey_test.go
+++ b/credentials/alts/internal/conn/aes128gcmrekey_test.go
@@ -21,7 +21,7 @@ package conn
 import (
 	"testing"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 // cryptoTestVector is struct for a rekey test vector
diff --git a/credentials/alts/core/conn/common.go b/credentials/alts/internal/conn/common.go
similarity index 100%
rename from credentials/alts/core/conn/common.go
rename to credentials/alts/internal/conn/common.go
diff --git a/credentials/alts/core/conn/counter.go b/credentials/alts/internal/conn/counter.go
similarity index 97%
rename from credentials/alts/core/conn/counter.go
rename to credentials/alts/internal/conn/counter.go
index 754dcfaa..280a6cdd 100644
--- a/credentials/alts/core/conn/counter.go
+++ b/credentials/alts/internal/conn/counter.go
@@ -21,7 +21,7 @@ package conn
 import (
 	"errors"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 const counterLen = 12
diff --git a/credentials/alts/core/conn/counter_test.go b/credentials/alts/internal/conn/counter_test.go
similarity index 98%
rename from credentials/alts/core/conn/counter_test.go
rename to credentials/alts/internal/conn/counter_test.go
index faf56369..6e623c0f 100644
--- a/credentials/alts/core/conn/counter_test.go
+++ b/credentials/alts/internal/conn/counter_test.go
@@ -22,7 +22,7 @@ import (
 	"bytes"
 	"testing"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 const (
diff --git a/credentials/alts/core/conn/record.go b/credentials/alts/internal/conn/record.go
similarity index 99%
rename from credentials/alts/core/conn/record.go
rename to credentials/alts/internal/conn/record.go
index cb514ebe..fd5a53d9 100644
--- a/credentials/alts/core/conn/record.go
+++ b/credentials/alts/internal/conn/record.go
@@ -26,7 +26,7 @@ import (
 	"math"
 	"net"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 // ALTSRecordCrypto is the interface for gRPC ALTS record protocol.
diff --git a/credentials/alts/core/conn/record_test.go b/credentials/alts/internal/conn/record_test.go
similarity index 99%
rename from credentials/alts/core/conn/record_test.go
rename to credentials/alts/internal/conn/record_test.go
index 5c3b8e2c..76e05549 100644
--- a/credentials/alts/core/conn/record_test.go
+++ b/credentials/alts/internal/conn/record_test.go
@@ -28,7 +28,7 @@ import (
 	"reflect"
 	"testing"
 
-	"google.golang.org/grpc/credentials/alts/core"
+	core "google.golang.org/grpc/credentials/alts/internal"
 )
 
 var (
diff --git a/credentials/alts/core/handshaker/handshaker.go b/credentials/alts/internal/handshaker/handshaker.go
similarity index 97%
rename from credentials/alts/core/handshaker/handshaker.go
rename to credentials/alts/internal/handshaker/handshaker.go
index a2049785..574884ad 100644
--- a/credentials/alts/core/handshaker/handshaker.go
+++ b/credentials/alts/internal/handshaker/handshaker.go
@@ -30,11 +30,11 @@ import (
 	grpc "google.golang.org/grpc"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/credentials"
-	"google.golang.org/grpc/credentials/alts/core"
-	"google.golang.org/grpc/credentials/alts/core/authinfo"
-	"google.golang.org/grpc/credentials/alts/core/conn"
-	altsgrpc "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+	core "google.golang.org/grpc/credentials/alts/internal"
+	"google.golang.org/grpc/credentials/alts/internal/authinfo"
+	"google.golang.org/grpc/credentials/alts/internal/conn"
+	altsgrpc "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 )
 
 const (
diff --git a/credentials/alts/core/handshaker/handshaker_test.go b/credentials/alts/internal/handshaker/handshaker_test.go
similarity index 97%
rename from credentials/alts/core/handshaker/handshaker_test.go
rename to credentials/alts/internal/handshaker/handshaker_test.go
index 343ac2ee..d870a1b3 100644
--- a/credentials/alts/core/handshaker/handshaker_test.go
+++ b/credentials/alts/internal/handshaker/handshaker_test.go
@@ -25,9 +25,9 @@ import (
 
 	"golang.org/x/net/context"
 	grpc "google.golang.org/grpc"
-	"google.golang.org/grpc/credentials/alts/core"
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
-	"google.golang.org/grpc/credentials/alts/core/testutil"
+	core "google.golang.org/grpc/credentials/alts/internal"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
+	"google.golang.org/grpc/credentials/alts/internal/testutil"
 )
 
 var (
diff --git a/credentials/alts/core/handshaker/service/service.go b/credentials/alts/internal/handshaker/service/service.go
similarity index 100%
rename from credentials/alts/core/handshaker/service/service.go
rename to credentials/alts/internal/handshaker/service/service.go
diff --git a/credentials/alts/core/handshaker/service/service_test.go b/credentials/alts/internal/handshaker/service/service_test.go
similarity index 100%
rename from credentials/alts/core/handshaker/service/service_test.go
rename to credentials/alts/internal/handshaker/service/service_test.go
diff --git a/credentials/alts/core/proto/grpc_gcp/altscontext.pb.go b/credentials/alts/internal/proto/grpc_gcp/altscontext.pb.go
similarity index 63%
rename from credentials/alts/core/proto/grpc_gcp/altscontext.pb.go
rename to credentials/alts/internal/proto/grpc_gcp/altscontext.pb.go
index cd4fe79b..18711a2b 100644
--- a/credentials/alts/core/proto/grpc_gcp/altscontext.pb.go
+++ b/credentials/alts/internal/proto/grpc_gcp/altscontext.pb.go
@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: grpc/gcp/altscontext.proto
 
-package grpc_gcp // import "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+package grpc_gcp // import "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 
 import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
@@ -40,7 +40,7 @@ func (m *AltsContext) Reset()         { *m = AltsContext{} }
 func (m *AltsContext) String() string { return proto.CompactTextString(m) }
 func (*AltsContext) ProtoMessage()    {}
 func (*AltsContext) Descriptor() ([]byte, []int) {
-	return fileDescriptor_altscontext_2f63c0ac7e856743, []int{0}
+	return fileDescriptor_altscontext_4d8d0120fd718d8c, []int{0}
 }
 func (m *AltsContext) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_AltsContext.Unmarshal(m, b)
@@ -107,31 +107,30 @@ func init() {
 }
 
 func init() {
-	proto.RegisterFile("grpc/gcp/altscontext.proto", fileDescriptor_altscontext_2f63c0ac7e856743)
+	proto.RegisterFile("grpc/gcp/altscontext.proto", fileDescriptor_altscontext_4d8d0120fd718d8c)
 }
 
-var fileDescriptor_altscontext_2f63c0ac7e856743 = []byte{
-	// 338 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x64, 0x91, 0x4d, 0x4b, 0x23, 0x41,
-	0x10, 0x86, 0x99, 0xec, 0x6e, 0xd8, 0xed, 0xb0, 0xc9, 0xee, 0x6c, 0xc2, 0x0e, 0x01, 0x21, 0x78,
-	0x71, 0x4e, 0x33, 0x1a, 0x8f, 0x82, 0x90, 0x78, 0x12, 0x3c, 0x84, 0x09, 0x78, 0xf0, 0x32, 0xb4,
-	0x95, 0xa2, 0x6d, 0xe8, 0x74, 0x35, 0xd5, 0x9d, 0xa0, 0x7f, 0xd5, 0x5f, 0x23, 0xd3, 0x93, 0x2f,
-	0xf4, 0x58, 0xf5, 0xbc, 0x6f, 0x7d, 0x8a, 0xb1, 0x62, 0x07, 0xa5, 0x02, 0x57, 0x4a, 0x13, 0x3c,
-	0x90, 0x0d, 0xf8, 0x1a, 0x0a, 0xc7, 0x14, 0x28, 0xfd, 0xd9, 0xb0, 0x42, 0x81, 0x1b, 0xe7, 0x07,
-	0x55, 0x60, 0x69, 0xbd, 0x23, 0x0e, 0xb5, 0x47, 0xd8, 0xb0, 0x0e, 0x6f, 0x35, 0xd0, 0x7a, 0x4d,
-	0xb6, 0xf5, 0x9c, 0xbf, 0x77, 0x44, 0x6f, 0x66, 0x82, 0xbf, 0x6b, 0x2b, 0xa5, 0x57, 0x62, 0x28,
-	0x9d, 0x33, 0x1a, 0x64, 0xd0, 0x64, 0xeb, 0x28, 0x02, 0x32, 0x59, 0x32, 0x49, 0xf2, 0x5f, 0xd5,
-	0xbf, 0x13, 0xb6, 0xd8, 0xa1, 0xf4, 0x42, 0x0c, 0x18, 0x81, 0x78, 0x75, 0x54, 0x77, 0xa2, 0xba,
-	0xdf, 0xa6, 0x0f, 0xc2, 0x5b, 0xd1, 0x3f, 0x0c, 0x61, 0x70, 0x8b, 0x26, 0xfb, 0x36, 0x49, 0xf2,
-	0xfe, 0xf4, 0x7f, 0xb1, 0x1f, 0xbc, 0x58, 0xee, 0xf8, 0x43, 0x83, 0xab, 0xdf, 0xfe, 0x34, 0x4c,
-	0x2f, 0xc5, 0xd0, 0x21, 0x72, 0xed, 0x91, 0xb7, 0x1a, 0xb0, 0x96, 0x00, 0xb4, 0xb1, 0x21, 0xfb,
-	0x1e, 0xbb, 0xa5, 0x0d, 0x5b, 0xb6, 0x68, 0xd6, 0x92, 0x74, 0x2a, 0x46, 0x86, 0x40, 0x9a, 0x2f,
-	0x96, 0x1f, 0xed, 0x3a, 0x11, 0x7e, 0xf2, 0xdc, 0x8b, 0xbf, 0xb1, 0x0b, 0x3b, 0xa8, 0xb7, 0xc8,
-	0x5e, 0x93, 0xf5, 0x59, 0x77, 0x92, 0xe4, 0xbd, 0xe9, 0xd9, 0x71, 0xd0, 0xca, 0xc1, 0x7e, 0xaf,
-	0xc7, 0x9d, 0xa8, 0x1a, 0x34, 0xbe, 0xca, 0xc1, 0x3e, 0x31, 0x7f, 0x11, 0x23, 0x4d, 0xad, 0xa7,
-	0xf9, 0x56, 0xa1, 0x6d, 0x40, 0xb6, 0xd2, 0xcc, 0xff, 0x9c, 0x9c, 0x3c, 0x96, 0x59, 0x24, 0x4f,
-	0x37, 0x8a, 0x48, 0x19, 0x2c, 0x14, 0x19, 0x69, 0x55, 0x41, 0xac, 0xca, 0xf8, 0x45, 0x60, 0x5c,
-	0xa1, 0x0d, 0x5a, 0x1a, 0x1f, 0x7f, 0x5e, 0x02, 0x31, 0x96, 0xf1, 0xd4, 0x51, 0x50, 0x2b, 0x70,
-	0xcf, 0xdd, 0x18, 0x5f, 0x7f, 0x04, 0x00, 0x00, 0xff, 0xff, 0xe8, 0x41, 0xe3, 0x52, 0x1f, 0x02,
-	0x00, 0x00,
+var fileDescriptor_altscontext_4d8d0120fd718d8c = []byte{
+	// 335 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x64, 0x91, 0xcf, 0x4b, 0x2b, 0x31,
+	0x10, 0xc7, 0xd9, 0xbe, 0xf7, 0xca, 0x33, 0xc5, 0x56, 0xd7, 0x16, 0x97, 0x82, 0x50, 0xbc, 0xb8,
+	0xa7, 0x5d, 0xad, 0x77, 0xa5, 0xf5, 0x24, 0x78, 0x28, 0x5b, 0xf0, 0xe0, 0x65, 0x89, 0xd3, 0x10,
+	0x02, 0x69, 0x26, 0x4c, 0xd2, 0xa2, 0xff, 0xaa, 0x7f, 0x8d, 0x6c, 0xd2, 0x6d, 0x8b, 0x1e, 0x67,
+	0x3e, 0xdf, 0xef, 0xfc, 0x64, 0x63, 0x49, 0x16, 0x4a, 0x09, 0xb6, 0xe4, 0xda, 0x3b, 0x40, 0xe3,
+	0xc5, 0x87, 0x2f, 0x2c, 0xa1, 0xc7, 0xf4, 0x7f, 0xc3, 0x0a, 0x09, 0x76, 0x9c, 0xef, 0x55, 0x9e,
+	0xb8, 0x71, 0x16, 0xc9, 0xd7, 0x4e, 0xc0, 0x86, 0x94, 0xff, 0xac, 0x01, 0xd7, 0x6b, 0x34, 0xd1,
+	0x73, 0xfd, 0xd5, 0x61, 0xbd, 0x99, 0xf6, 0xee, 0x29, 0x56, 0x4a, 0xef, 0xd8, 0x90, 0x5b, 0xab,
+	0x15, 0x70, 0xaf, 0xd0, 0xd4, 0x41, 0x04, 0xa8, 0xb3, 0x64, 0x92, 0xe4, 0x27, 0xd5, 0xc5, 0x11,
+	0x5b, 0xec, 0x50, 0x7a, 0xc3, 0x06, 0x24, 0x00, 0x69, 0x75, 0x50, 0x77, 0x82, 0xba, 0x1f, 0xd3,
+	0x7b, 0xe1, 0x03, 0xeb, 0xef, 0x87, 0xd0, 0x62, 0x2b, 0x74, 0xf6, 0x67, 0x92, 0xe4, 0xfd, 0xe9,
+	0x65, 0xd1, 0x0e, 0x5e, 0x2c, 0x77, 0xfc, 0xa5, 0xc1, 0xd5, 0xa9, 0x3b, 0x0e, 0xd3, 0x5b, 0x36,
+	0xb4, 0x42, 0x50, 0xed, 0x04, 0x6d, 0x15, 0x88, 0x9a, 0x03, 0xe0, 0xc6, 0xf8, 0xec, 0x6f, 0xe8,
+	0x96, 0x36, 0x6c, 0x19, 0xd1, 0x2c, 0x92, 0x74, 0xca, 0x46, 0x1a, 0x81, 0xeb, 0x5f, 0x96, 0x7f,
+	0x71, 0x9d, 0x00, 0x7f, 0x78, 0x9e, 0xd9, 0x79, 0xe8, 0x42, 0x16, 0xea, 0xad, 0x20, 0xa7, 0xd0,
+	0xb8, 0xac, 0x3b, 0x49, 0xf2, 0xde, 0xf4, 0xea, 0x30, 0x68, 0x65, 0xa1, 0xdd, 0xeb, 0x75, 0x27,
+	0xaa, 0x06, 0x8d, 0xaf, 0xb2, 0xd0, 0x26, 0xe6, 0x9a, 0x8d, 0x14, 0x46, 0x4f, 0xf3, 0xad, 0x42,
+	0x19, 0x2f, 0xc8, 0x70, 0x3d, 0x3f, 0x3b, 0x3a, 0x79, 0x28, 0xb3, 0x48, 0xde, 0x1e, 0x25, 0xa2,
+	0xd4, 0xa2, 0x90, 0xa8, 0xb9, 0x91, 0x05, 0x92, 0x2c, 0xc3, 0x17, 0x81, 0xc4, 0x4a, 0x18, 0xaf,
+	0xb8, 0x76, 0xe1, 0xe7, 0x65, 0x5b, 0xa5, 0x0c, 0xe7, 0x0e, 0xa2, 0x5a, 0x82, 0x7d, 0xef, 0x86,
+	0xf8, 0xfe, 0x3b, 0x00, 0x00, 0xff, 0xff, 0x15, 0xf8, 0xd5, 0xb6, 0x23, 0x02, 0x00, 0x00,
 }
diff --git a/credentials/alts/core/proto/grpc_gcp/handshaker.pb.go b/credentials/alts/internal/proto/grpc_gcp/handshaker.pb.go
similarity index 83%
rename from credentials/alts/core/proto/grpc_gcp/handshaker.pb.go
rename to credentials/alts/internal/proto/grpc_gcp/handshaker.pb.go
index e03e0fed..cbf85645 100644
--- a/credentials/alts/core/proto/grpc_gcp/handshaker.pb.go
+++ b/credentials/alts/internal/proto/grpc_gcp/handshaker.pb.go
@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: grpc/gcp/handshaker.proto
 
-package grpc_gcp // import "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+package grpc_gcp // import "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 
 import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
@@ -49,7 +49,7 @@ func (x HandshakeProtocol) String() string {
 	return proto.EnumName(HandshakeProtocol_name, int32(x))
 }
 func (HandshakeProtocol) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{0}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{0}
 }
 
 type NetworkProtocol int32
@@ -75,7 +75,7 @@ func (x NetworkProtocol) String() string {
 	return proto.EnumName(NetworkProtocol_name, int32(x))
 }
 func (NetworkProtocol) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{1}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{1}
 }
 
 type Endpoint struct {
@@ -95,7 +95,7 @@ func (m *Endpoint) Reset()         { *m = Endpoint{} }
 func (m *Endpoint) String() string { return proto.CompactTextString(m) }
 func (*Endpoint) ProtoMessage()    {}
 func (*Endpoint) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{0}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{0}
 }
 func (m *Endpoint) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Endpoint.Unmarshal(m, b)
@@ -150,7 +150,7 @@ func (m *Identity) Reset()         { *m = Identity{} }
 func (m *Identity) String() string { return proto.CompactTextString(m) }
 func (*Identity) ProtoMessage()    {}
 func (*Identity) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{1}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{1}
 }
 func (m *Identity) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Identity.Unmarshal(m, b)
@@ -310,7 +310,7 @@ func (m *StartClientHandshakeReq) Reset()         { *m = StartClientHandshakeReq
 func (m *StartClientHandshakeReq) String() string { return proto.CompactTextString(m) }
 func (*StartClientHandshakeReq) ProtoMessage()    {}
 func (*StartClientHandshakeReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{2}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{2}
 }
 func (m *StartClientHandshakeReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_StartClientHandshakeReq.Unmarshal(m, b)
@@ -409,7 +409,7 @@ func (m *ServerHandshakeParameters) Reset()         { *m = ServerHandshakeParame
 func (m *ServerHandshakeParameters) String() string { return proto.CompactTextString(m) }
 func (*ServerHandshakeParameters) ProtoMessage()    {}
 func (*ServerHandshakeParameters) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{3}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{3}
 }
 func (m *ServerHandshakeParameters) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_ServerHandshakeParameters.Unmarshal(m, b)
@@ -473,7 +473,7 @@ func (m *StartServerHandshakeReq) Reset()         { *m = StartServerHandshakeReq
 func (m *StartServerHandshakeReq) String() string { return proto.CompactTextString(m) }
 func (*StartServerHandshakeReq) ProtoMessage()    {}
 func (*StartServerHandshakeReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{4}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{4}
 }
 func (m *StartServerHandshakeReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_StartServerHandshakeReq.Unmarshal(m, b)
@@ -549,7 +549,7 @@ func (m *NextHandshakeMessageReq) Reset()         { *m = NextHandshakeMessageReq
 func (m *NextHandshakeMessageReq) String() string { return proto.CompactTextString(m) }
 func (*NextHandshakeMessageReq) ProtoMessage()    {}
 func (*NextHandshakeMessageReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{5}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{5}
 }
 func (m *NextHandshakeMessageReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_NextHandshakeMessageReq.Unmarshal(m, b)
@@ -591,7 +591,7 @@ func (m *HandshakerReq) Reset()         { *m = HandshakerReq{} }
 func (m *HandshakerReq) String() string { return proto.CompactTextString(m) }
 func (*HandshakerReq) ProtoMessage()    {}
 func (*HandshakerReq) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{6}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{6}
 }
 func (m *HandshakerReq) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_HandshakerReq.Unmarshal(m, b)
@@ -782,7 +782,7 @@ func (m *HandshakerResult) Reset()         { *m = HandshakerResult{} }
 func (m *HandshakerResult) String() string { return proto.CompactTextString(m) }
 func (*HandshakerResult) ProtoMessage()    {}
 func (*HandshakerResult) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{7}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{7}
 }
 func (m *HandshakerResult) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_HandshakerResult.Unmarshal(m, b)
@@ -865,7 +865,7 @@ func (m *HandshakerStatus) Reset()         { *m = HandshakerStatus{} }
 func (m *HandshakerStatus) String() string { return proto.CompactTextString(m) }
 func (*HandshakerStatus) ProtoMessage()    {}
 func (*HandshakerStatus) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{8}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{8}
 }
 func (m *HandshakerStatus) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_HandshakerStatus.Unmarshal(m, b)
@@ -924,7 +924,7 @@ func (m *HandshakerResp) Reset()         { *m = HandshakerResp{} }
 func (m *HandshakerResp) String() string { return proto.CompactTextString(m) }
 func (*HandshakerResp) ProtoMessage()    {}
 func (*HandshakerResp) Descriptor() ([]byte, []int) {
-	return fileDescriptor_handshaker_b28e45bdd1661054, []int{9}
+	return fileDescriptor_handshaker_cd0a1186560da71f, []int{9}
 }
 func (m *HandshakerResp) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_HandshakerResp.Unmarshal(m, b)
@@ -1105,80 +1105,80 @@ var _HandshakerService_serviceDesc = grpc.ServiceDesc{
 }
 
 func init() {
-	proto.RegisterFile("grpc/gcp/handshaker.proto", fileDescriptor_handshaker_b28e45bdd1661054)
+	proto.RegisterFile("grpc/gcp/handshaker.proto", fileDescriptor_handshaker_cd0a1186560da71f)
 }
 
-var fileDescriptor_handshaker_b28e45bdd1661054 = []byte{
-	// 1128 bytes of a gzipped FileDescriptorProto
+var fileDescriptor_handshaker_cd0a1186560da71f = []byte{
+	// 1127 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xa4, 0x56, 0xdf, 0x6e, 0x1a, 0xc7,
-	0x17, 0xf6, 0x02, 0xb6, 0xe1, 0x60, 0xfe, 0x78, 0x92, 0x28, 0xd8, 0x49, 0x7e, 0x3f, 0x4a, 0x55,
-	0x95, 0xf8, 0x02, 0x5a, 0xd2, 0x2a, 0x4d, 0xa2, 0xaa, 0xb1, 0x31, 0x16, 0x6e, 0x5c, 0x8c, 0x16,
-	0xa7, 0x95, 0x9a, 0x8b, 0xd5, 0x64, 0x39, 0x59, 0xaf, 0x58, 0x66, 0xd6, 0x33, 0x83, 0x1b, 0x1e,
-	0xa0, 0x8f, 0xd3, 0x57, 0xe8, 0xdb, 0xf4, 0x0d, 0x7a, 0xdf, 0x6a, 0x67, 0xff, 0x61, 0x0c, 0x51,
-	0xa2, 0xde, 0xed, 0xce, 0x7c, 0xdf, 0xd9, 0x73, 0xbe, 0xf3, 0xcd, 0xd9, 0x81, 0x3d, 0x47, 0xf8,
-	0x76, 0xdb, 0xb1, 0xfd, 0xf6, 0x25, 0x65, 0x63, 0x79, 0x49, 0x27, 0x28, 0x5a, 0xbe, 0xe0, 0x8a,
-	0x93, 0x7c, 0xb0, 0xd5, 0x72, 0x6c, 0x7f, 0xbf, 0x99, 0x80, 0x94, 0xa0, 0x4c, 0xfa, 0x5c, 0x28,
-	0x4b, 0xa2, 0x3d, 0x13, 0xae, 0x9a, 0x5b, 0x36, 0x9f, 0x4e, 0x39, 0x0b, 0x39, 0x0d, 0x05, 0xf9,
-	0x1e, 0x1b, 0xfb, 0xdc, 0x65, 0x8a, 0x3c, 0x02, 0x70, 0x7d, 0x8b, 0x8e, 0xc7, 0x02, 0xa5, 0xac,
-	0x19, 0x75, 0xa3, 0x59, 0x30, 0x0b, 0xae, 0x7f, 0x18, 0x2e, 0x10, 0x02, 0xb9, 0x20, 0x50, 0x2d,
-	0x53, 0x37, 0x9a, 0x9b, 0xa6, 0x7e, 0x26, 0xdf, 0x42, 0x5e, 0xc7, 0xb1, 0xb9, 0x57, 0xcb, 0xd6,
-	0x8d, 0x66, 0xb9, 0xb3, 0xd7, 0x8a, 0xb3, 0x68, 0x0d, 0x50, 0xfd, 0xc6, 0xc5, 0x64, 0x18, 0x01,
-	0xcc, 0x04, 0xda, 0x40, 0xc8, 0x9f, 0x8e, 0x91, 0x29, 0x57, 0xcd, 0xc9, 0x63, 0xa8, 0x48, 0x14,
-	0xd7, 0xae, 0x8d, 0x16, 0xb5, 0x6d, 0x3e, 0x63, 0x2a, 0xfc, 0x74, 0x7f, 0xc3, 0x2c, 0x47, 0x1b,
-	0x87, 0xe1, 0x3a, 0x79, 0x08, 0xf9, 0x4b, 0x2e, 0x15, 0xa3, 0x53, 0xd4, 0x59, 0x04, 0x98, 0x64,
-	0xe5, 0xa8, 0x0a, 0x65, 0x37, 0x0a, 0x6a, 0x71, 0x86, 0xfc, 0x5d, 0xe3, 0x8f, 0x1c, 0xdc, 0x1f,
-	0x29, 0x2a, 0x54, 0xd7, 0x73, 0x91, 0xa9, 0x7e, 0x2c, 0x98, 0x89, 0x57, 0xe4, 0x0d, 0x3c, 0x48,
-	0x04, 0x4c, 0xb5, 0x49, 0x8a, 0x31, 0x74, 0x31, 0x0f, 0xd2, 0x62, 0x12, 0x72, 0x52, 0xce, 0x5e,
-	0xc2, 0x1f, 0x45, 0xf4, 0x78, 0x8b, 0x3c, 0x81, 0x7b, 0xd4, 0xf7, 0x3d, 0xd7, 0xa6, 0xca, 0xe5,
-	0x2c, 0x89, 0x2a, 0x6b, 0x99, 0x7a, 0xb6, 0x59, 0x30, 0xef, 0x2e, 0x6c, 0xc6, 0x1c, 0x49, 0x1e,
-	0x43, 0x55, 0xa0, 0xcd, 0xc5, 0x78, 0x01, 0x9f, 0xd5, 0xf8, 0x4a, 0xb8, 0x9e, 0x42, 0x7f, 0x80,
-	0x5d, 0x45, 0x85, 0x83, 0xca, 0x8a, 0x2a, 0x76, 0x51, 0xd6, 0x72, 0xf5, 0x6c, 0xb3, 0xd8, 0x21,
-	0x69, 0xca, 0xb1, 0xc4, 0x66, 0x35, 0x04, 0x9f, 0x26, 0x58, 0xf2, 0x0c, 0xca, 0x1e, 0xb7, 0xa9,
-	0x17, 0xf3, 0xe7, 0xb5, 0xcd, 0xba, 0xb1, 0x86, 0x5d, 0xd2, 0xc8, 0xa4, 0x5f, 0x09, 0x15, 0x23,
-	0xdf, 0xd4, 0xb6, 0x96, 0xa9, 0xb1, 0xa3, 0x22, 0x6a, 0x62, 0xb0, 0x17, 0x50, 0x11, 0x38, 0xe5,
-	0x0a, 0x53, 0xee, 0xf6, 0x5a, 0x6e, 0x39, 0x84, 0x26, 0xe4, 0xff, 0x43, 0x31, 0xaa, 0x59, 0xf7,
-	0x3f, 0xaf, 0xed, 0x09, 0xe1, 0xd2, 0x80, 0x4e, 0x91, 0xbc, 0x84, 0x1d, 0xe1, 0xdb, 0xd6, 0x35,
-	0x0a, 0xe9, 0x72, 0x26, 0x6b, 0x05, 0x1d, 0xfa, 0x51, 0x1a, 0xda, 0xf4, 0xed, 0x58, 0xc2, 0x9f,
-	0x23, 0x90, 0x59, 0x14, 0xbe, 0x1d, 0xbf, 0x34, 0x7e, 0x37, 0x60, 0x6f, 0x84, 0xe2, 0x1a, 0x45,
-	0xda, 0x6d, 0x2a, 0xe8, 0x14, 0x15, 0x8a, 0xd5, 0xfd, 0x31, 0x56, 0xf7, 0xe7, 0x7b, 0xa8, 0xde,
-	0x90, 0x37, 0x68, 0x4f, 0x66, 0x6d, 0x7b, 0x2a, 0x8b, 0x02, 0xbb, 0x28, 0x1b, 0xff, 0x64, 0x23,
-	0xdf, 0x2e, 0x25, 0x13, 0xf8, 0x76, 0xad, 0xb5, 0x8c, 0x0f, 0x58, 0x6b, 0x0a, 0x77, 0x53, 0xb3,
-	0xfb, 0x49, 0x49, 0x51, 0x4e, 0xcf, 0xd3, 0x9c, 0xd6, 0x7c, 0xb5, 0xb5, 0x42, 0x8f, 0x1e, 0x53,
-	0x62, 0x6e, 0xde, 0xb9, 0x5c, 0xa1, 0xd4, 0x1e, 0xe4, 0x5d, 0x66, 0xbd, 0x9d, 0x2b, 0x94, 0x7a,
-	0x2a, 0xec, 0x98, 0xdb, 0x2e, 0x3b, 0x0a, 0x5e, 0x57, 0xb8, 0x27, 0xf7, 0x1f, 0xdc, 0xb3, 0xf9,
-	0xd1, 0xee, 0x59, 0x36, 0xc7, 0xd6, 0xa7, 0x9a, 0x63, 0x7f, 0x02, 0xb5, 0x75, 0x2a, 0x90, 0x2a,
-	0x64, 0x27, 0x38, 0xd7, 0x43, 0x63, 0xd3, 0x0c, 0x1e, 0xc9, 0x33, 0xd8, 0xbc, 0xa6, 0xde, 0x2c,
-	0x9c, 0x53, 0xc5, 0xce, 0xe7, 0x0b, 0x12, 0xaf, 0x33, 0x98, 0x19, 0x32, 0x9e, 0x67, 0xbe, 0x33,
-	0x1a, 0xdf, 0xc0, 0xfd, 0x01, 0xbe, 0x4f, 0x27, 0xd6, 0x4f, 0x28, 0x25, 0x75, 0xb4, 0x01, 0x16,
-	0xc5, 0x35, 0x6e, 0x88, 0xdb, 0xf8, 0xcb, 0x80, 0x52, 0x42, 0x11, 0x01, 0xf8, 0x04, 0x76, 0x6c,
-	0x3d, 0xfb, 0x2c, 0x19, 0x74, 0x56, 0x13, 0x8a, 0x9d, 0xcf, 0x96, 0x1a, 0x7e, 0x7b, 0x3c, 0xf6,
-	0x37, 0xcc, 0x62, 0x48, 0xd4, 0x80, 0x20, 0x8e, 0xd4, 0x79, 0x47, 0x71, 0x32, 0x2b, 0xe3, 0xdc,
-	0x36, 0x4e, 0x10, 0x27, 0x24, 0x86, 0x71, 0x9e, 0x42, 0x8e, 0xe1, 0x7b, 0xa5, 0x5d, 0x71, 0x83,
-	0xbf, 0xa6, 0xda, 0xfe, 0x86, 0xa9, 0x09, 0x47, 0x45, 0x28, 0x08, 0xbc, 0x8a, 0xe6, 0xfa, 0xdf,
-	0x19, 0xa8, 0x2e, 0xd6, 0x29, 0x67, 0x9e, 0x22, 0x5f, 0xc3, 0xdd, 0x55, 0x07, 0x23, 0xfa, 0x8f,
-	0xdd, 0x59, 0x71, 0x2e, 0xc8, 0x97, 0x50, 0x59, 0x3a, 0xd1, 0xe1, 0x6f, 0x25, 0x70, 0xcf, 0xe2,
-	0x81, 0x0e, 0x34, 0x9f, 0xe0, 0xdc, 0x1a, 0x53, 0x45, 0x63, 0x43, 0x4f, 0x70, 0x7e, 0x4c, 0x15,
-	0x25, 0x4f, 0xa1, 0xe4, 0x23, 0x8a, 0x74, 0x90, 0xe6, 0xd6, 0x0e, 0xd2, 0x9d, 0x00, 0x78, 0x7b,
-	0x8e, 0x7e, 0xfa, 0x08, 0x3e, 0x80, 0xdd, 0x09, 0xa2, 0x6f, 0xd9, 0x97, 0x94, 0x31, 0xf4, 0x2c,
-	0xee, 0x23, 0xd3, 0x8e, 0xce, 0x9b, 0x95, 0x60, 0xa3, 0x1b, 0xae, 0x9f, 0xfb, 0xc8, 0xc8, 0x29,
-	0xec, 0xea, 0xfc, 0x6e, 0xb8, 0x7f, 0xfb, 0x63, 0xdc, 0x5f, 0x09, 0x78, 0xe6, 0xc2, 0x78, 0x7c,
-	0xb9, 0xa8, 0xfa, 0x48, 0x51, 0x35, 0xd3, 0x97, 0x02, 0x9b, 0x8f, 0x51, 0xab, 0x5c, 0x32, 0xf5,
-	0x33, 0xa9, 0xc1, 0xf6, 0x18, 0x15, 0x75, 0xf5, 0xff, 0x2e, 0x90, 0x33, 0x7e, 0x6d, 0xfc, 0x69,
-	0x40, 0xf9, 0x46, 0xe3, 0xfc, 0xe0, 0xd2, 0xc1, 0x67, 0xca, 0x7a, 0x17, 0x9c, 0x82, 0xd8, 0xd0,
-	0x05, 0x3e, 0x53, 0x27, 0x7a, 0x81, 0x7c, 0x01, 0x65, 0x6d, 0x75, 0xcb, 0xe6, 0x4c, 0xce, 0xa6,
-	0x38, 0xd6, 0x21, 0x4b, 0x66, 0x49, 0xaf, 0x76, 0xa3, 0x45, 0xd2, 0x81, 0x2d, 0xa1, 0x6d, 0x10,
-	0x39, 0x6b, 0x7f, 0xc5, 0x8f, 0x3b, 0x32, 0x8a, 0x19, 0x21, 0x03, 0x8e, 0xd4, 0x45, 0x44, 0x2d,
-	0x5b, 0xc9, 0x09, 0xcb, 0x34, 0x23, 0xe4, 0xc1, 0x8f, 0xb0, 0x7b, 0xeb, 0x22, 0x40, 0x1a, 0xf0,
-	0xbf, 0xfe, 0xe1, 0xe0, 0x78, 0xd4, 0x3f, 0x7c, 0xd5, 0xb3, 0x86, 0xe6, 0xf9, 0xc5, 0x79, 0xf7,
-	0xfc, 0xcc, 0x7a, 0x3d, 0x18, 0x0d, 0x7b, 0xdd, 0xd3, 0x93, 0xd3, 0xde, 0x71, 0x75, 0x83, 0x6c,
-	0x43, 0xf6, 0xe2, 0x6c, 0x54, 0x35, 0x48, 0x1e, 0x72, 0x87, 0x67, 0x17, 0xa3, 0x6a, 0xe6, 0xa0,
-	0x07, 0x95, 0xa5, 0x1b, 0x12, 0xa9, 0xc3, 0xc3, 0x41, 0xef, 0xe2, 0x97, 0x73, 0xf3, 0xd5, 0x87,
-	0xe2, 0x74, 0x87, 0x55, 0x23, 0x78, 0x78, 0x7d, 0x3c, 0xac, 0x66, 0x3a, 0x6f, 0x16, 0x52, 0x12,
-	0xa3, 0xf0, 0xc2, 0x44, 0x4e, 0xa0, 0x78, 0xcc, 0x93, 0x65, 0x72, 0x7f, 0xb5, 0x1c, 0x57, 0xfb,
-	0xb5, 0x35, 0x3a, 0xf9, 0x8d, 0x8d, 0xa6, 0xf1, 0x95, 0x71, 0xe4, 0xc0, 0x3d, 0x97, 0x87, 0x18,
-	0xea, 0x29, 0xd9, 0x72, 0x99, 0x42, 0xc1, 0xa8, 0x77, 0x54, 0x49, 0xe1, 0x3a, 0xfb, 0xa1, 0xf1,
-	0xeb, 0x0b, 0x87, 0x73, 0xc7, 0xc3, 0x96, 0xc3, 0x3d, 0xca, 0x9c, 0x16, 0x17, 0x4e, 0x5b, 0x5f,
-	0x43, 0x6d, 0x81, 0xda, 0xb8, 0xd4, 0x93, 0xed, 0x20, 0x48, 0xdb, 0xe6, 0x02, 0xdb, 0xfa, 0xc4,
-	0x69, 0x80, 0xe5, 0xd8, 0xfe, 0xdb, 0x2d, 0xfd, 0xfe, 0xe4, 0xdf, 0x00, 0x00, 0x00, 0xff, 0xff,
-	0xfa, 0xd2, 0x42, 0x7f, 0xdf, 0x0a, 0x00, 0x00,
+	0x17, 0xf6, 0x02, 0xb6, 0xf1, 0xc1, 0xfc, 0xf1, 0x24, 0x51, 0xb0, 0x93, 0xfc, 0x7e, 0x94, 0xaa,
+	0x2a, 0xc9, 0x05, 0xb4, 0xa4, 0x55, 0x9a, 0x54, 0x55, 0x62, 0x63, 0x2c, 0xdc, 0xa4, 0x18, 0x0d,
+	0x4e, 0x2b, 0x35, 0x17, 0xab, 0xc9, 0x72, 0x82, 0x57, 0x2c, 0x33, 0xeb, 0x99, 0xc1, 0x0d, 0x0f,
+	0xd0, 0xc7, 0xe9, 0x2b, 0xf4, 0x6d, 0xfa, 0x06, 0xbd, 0x6f, 0xb5, 0xb3, 0xff, 0x30, 0x86, 0x28,
+	0x51, 0xef, 0x76, 0x67, 0xbe, 0xef, 0xec, 0x39, 0xdf, 0xf9, 0xe6, 0xec, 0xc0, 0xfe, 0x58, 0xfa,
+	0x4e, 0x6b, 0xec, 0xf8, 0xad, 0x0b, 0xc6, 0x47, 0xea, 0x82, 0x4d, 0x50, 0x36, 0x7d, 0x29, 0xb4,
+	0x20, 0xf9, 0x60, 0xab, 0x39, 0x76, 0xfc, 0x83, 0x46, 0x02, 0xd2, 0x92, 0x71, 0xe5, 0x0b, 0xa9,
+	0x6d, 0x85, 0xce, 0x4c, 0xba, 0x7a, 0x6e, 0x3b, 0x62, 0x3a, 0x15, 0x3c, 0xe4, 0xd4, 0x35, 0xe4,
+	0xbb, 0x7c, 0xe4, 0x0b, 0x97, 0x6b, 0xf2, 0x00, 0xc0, 0xf5, 0x6d, 0x36, 0x1a, 0x49, 0x54, 0xaa,
+	0x6a, 0xd5, 0xac, 0xc6, 0x0e, 0xdd, 0x71, 0xfd, 0xc3, 0x70, 0x81, 0x10, 0xc8, 0x05, 0x81, 0xaa,
+	0x99, 0x9a, 0xd5, 0xd8, 0xa4, 0xe6, 0x99, 0x7c, 0x0b, 0x79, 0x13, 0xc7, 0x11, 0x5e, 0x35, 0x5b,
+	0xb3, 0x1a, 0xa5, 0xf6, 0x7e, 0x33, 0xce, 0xa2, 0xd9, 0x47, 0xfd, 0x9b, 0x90, 0x93, 0x41, 0x04,
+	0xa0, 0x09, 0xb4, 0x8e, 0x90, 0x3f, 0x1d, 0x21, 0xd7, 0xae, 0x9e, 0x93, 0x87, 0x50, 0x56, 0x28,
+	0xaf, 0x5c, 0x07, 0x6d, 0xe6, 0x38, 0x62, 0xc6, 0x75, 0xf8, 0xe9, 0xde, 0x06, 0x2d, 0x45, 0x1b,
+	0x87, 0xe1, 0x3a, 0xb9, 0x0f, 0xf9, 0x0b, 0xa1, 0x34, 0x67, 0x53, 0x34, 0x59, 0x04, 0x98, 0x64,
+	0xe5, 0xa8, 0x02, 0x25, 0x37, 0x0a, 0x6a, 0x0b, 0x8e, 0xe2, 0x5d, 0xfd, 0x8f, 0x1c, 0xdc, 0x1d,
+	0x6a, 0x26, 0x75, 0xc7, 0x73, 0x91, 0xeb, 0x5e, 0x2c, 0x18, 0xc5, 0x4b, 0xf2, 0x06, 0xee, 0x25,
+	0x02, 0xa6, 0xda, 0x24, 0xc5, 0x58, 0xa6, 0x98, 0x7b, 0x69, 0x31, 0x09, 0x39, 0x29, 0x67, 0x3f,
+	0xe1, 0x0f, 0x23, 0x7a, 0xbc, 0x45, 0x1e, 0xc3, 0x1d, 0xe6, 0xfb, 0x9e, 0xeb, 0x30, 0xed, 0x0a,
+	0x9e, 0x44, 0x55, 0xd5, 0x4c, 0x2d, 0xdb, 0xd8, 0xa1, 0xb7, 0x17, 0x36, 0x63, 0x8e, 0x22, 0x0f,
+	0xa1, 0x22, 0xd1, 0x11, 0x72, 0xb4, 0x80, 0xcf, 0x1a, 0x7c, 0x39, 0x5c, 0x4f, 0xa1, 0xcf, 0x61,
+	0x4f, 0x33, 0x39, 0x46, 0x6d, 0x47, 0x15, 0xbb, 0xa8, 0xaa, 0xb9, 0x5a, 0xb6, 0x51, 0x68, 0x93,
+	0x34, 0xe5, 0x58, 0x62, 0x5a, 0x09, 0xc1, 0xa7, 0x09, 0x96, 0x3c, 0x85, 0x92, 0x27, 0x1c, 0xe6,
+	0xc5, 0xfc, 0x79, 0x75, 0xb3, 0x66, 0xad, 0x61, 0x17, 0x0d, 0x32, 0xe9, 0x57, 0x42, 0xc5, 0xc8,
+	0x37, 0xd5, 0xad, 0x65, 0x6a, 0xec, 0xa8, 0x88, 0x9a, 0x18, 0xec, 0x7b, 0x28, 0x4b, 0x9c, 0x0a,
+	0x8d, 0x29, 0x77, 0x7b, 0x2d, 0xb7, 0x14, 0x42, 0x13, 0xf2, 0xff, 0xa1, 0x10, 0xd5, 0x6c, 0xfa,
+	0x9f, 0x37, 0xf6, 0x84, 0x70, 0xa9, 0xcf, 0xa6, 0x48, 0x5e, 0xc0, 0xae, 0xf4, 0x1d, 0xfb, 0x0a,
+	0xa5, 0x72, 0x05, 0x57, 0xd5, 0x1d, 0x13, 0xfa, 0x41, 0x1a, 0x9a, 0xfa, 0x4e, 0x2c, 0xe1, 0xcf,
+	0x11, 0x88, 0x16, 0xa4, 0xef, 0xc4, 0x2f, 0xf5, 0xdf, 0x2d, 0xd8, 0x1f, 0xa2, 0xbc, 0x42, 0x99,
+	0x76, 0x9b, 0x49, 0x36, 0x45, 0x8d, 0x72, 0x75, 0x7f, 0xac, 0xd5, 0xfd, 0xf9, 0x01, 0x2a, 0xd7,
+	0xe4, 0x0d, 0xda, 0x93, 0x59, 0xdb, 0x9e, 0xf2, 0xa2, 0xc0, 0x2e, 0xaa, 0xfa, 0x3f, 0xd9, 0xc8,
+	0xb7, 0x4b, 0xc9, 0x04, 0xbe, 0x5d, 0x6b, 0x2d, 0xeb, 0x03, 0xd6, 0x9a, 0xc2, 0xed, 0xd4, 0xec,
+	0x7e, 0x52, 0x52, 0x94, 0xd3, 0xb3, 0x34, 0xa7, 0x35, 0x5f, 0x6d, 0xae, 0xd0, 0xa3, 0xcb, 0xb5,
+	0x9c, 0xd3, 0x5b, 0x17, 0x2b, 0x94, 0xda, 0x87, 0xbc, 0xcb, 0xed, 0xb7, 0x73, 0x8d, 0xca, 0x4c,
+	0x85, 0x5d, 0xba, 0xed, 0xf2, 0xa3, 0xe0, 0x75, 0x85, 0x7b, 0x72, 0xff, 0xc1, 0x3d, 0x9b, 0x1f,
+	0xed, 0x9e, 0x65, 0x73, 0x6c, 0x7d, 0xaa, 0x39, 0x0e, 0x26, 0x50, 0x5d, 0xa7, 0x02, 0xa9, 0x40,
+	0x76, 0x82, 0x73, 0x33, 0x34, 0x36, 0x69, 0xf0, 0x48, 0x9e, 0xc2, 0xe6, 0x15, 0xf3, 0x66, 0xe1,
+	0x9c, 0x2a, 0xb4, 0x3f, 0x5f, 0x90, 0x78, 0x9d, 0xc1, 0x68, 0xc8, 0x78, 0x96, 0xf9, 0xce, 0xaa,
+	0x7f, 0x03, 0x77, 0xfb, 0xf8, 0x3e, 0x9d, 0x58, 0x3f, 0xa1, 0x52, 0x6c, 0x6c, 0x0c, 0xb0, 0x28,
+	0xae, 0x75, 0x4d, 0xdc, 0xfa, 0x5f, 0x16, 0x14, 0x13, 0x8a, 0x0c, 0xc0, 0x27, 0xb0, 0xeb, 0x98,
+	0xd9, 0x67, 0xab, 0xa0, 0xb3, 0x86, 0x50, 0x68, 0x7f, 0xb6, 0xd4, 0xf0, 0x9b, 0xe3, 0xb1, 0xb7,
+	0x41, 0x0b, 0x21, 0xd1, 0x00, 0x82, 0x38, 0xca, 0xe4, 0x1d, 0xc5, 0xc9, 0xac, 0x8c, 0x73, 0xd3,
+	0x38, 0x41, 0x9c, 0x90, 0x18, 0xc6, 0x79, 0x02, 0x39, 0x8e, 0xef, 0xb5, 0x71, 0xc5, 0x35, 0xfe,
+	0x9a, 0x6a, 0x7b, 0x1b, 0xd4, 0x10, 0x8e, 0x0a, 0xb0, 0x23, 0xf1, 0x32, 0x9a, 0xeb, 0x7f, 0x67,
+	0xa0, 0xb2, 0x58, 0xa7, 0x9a, 0x79, 0x9a, 0x7c, 0x0d, 0xb7, 0x57, 0x1d, 0x8c, 0xe8, 0x3f, 0x76,
+	0x6b, 0xc5, 0xb9, 0x20, 0x5f, 0x42, 0x79, 0xe9, 0x44, 0x87, 0xbf, 0x95, 0xc0, 0x3d, 0x8b, 0x07,
+	0x3a, 0xd0, 0x7c, 0x82, 0x73, 0x7b, 0xc4, 0x34, 0x8b, 0x0d, 0x3d, 0xc1, 0xf9, 0x31, 0xd3, 0x8c,
+	0x3c, 0x81, 0xa2, 0x8f, 0x28, 0xd3, 0x41, 0x9a, 0x5b, 0x3b, 0x48, 0x77, 0x03, 0xe0, 0xcd, 0x39,
+	0xfa, 0xe9, 0x23, 0xf8, 0x11, 0xec, 0x4d, 0x10, 0x7d, 0xdb, 0xb9, 0x60, 0x9c, 0xa3, 0x67, 0x0b,
+	0x1f, 0xb9, 0x71, 0x74, 0x9e, 0x96, 0x83, 0x8d, 0x4e, 0xb8, 0x7e, 0xe6, 0x23, 0x27, 0xa7, 0xb0,
+	0x67, 0xf2, 0xbb, 0xe6, 0xfe, 0xed, 0x8f, 0x71, 0x7f, 0x39, 0xe0, 0xd1, 0x85, 0xf1, 0xf8, 0x62,
+	0x51, 0xf5, 0xa1, 0x66, 0x7a, 0x66, 0x2e, 0x05, 0x8e, 0x18, 0xa1, 0x51, 0xb9, 0x48, 0xcd, 0x33,
+	0xa9, 0xc2, 0xf6, 0x08, 0x35, 0x73, 0xcd, 0xff, 0x2e, 0x90, 0x33, 0x7e, 0xad, 0xff, 0x69, 0x41,
+	0xe9, 0x5a, 0xe3, 0xfc, 0xe0, 0xd2, 0x21, 0x66, 0xda, 0x7e, 0x17, 0x9c, 0x82, 0xd8, 0xd0, 0x3b,
+	0x62, 0xa6, 0x4f, 0xcc, 0x02, 0xf9, 0x02, 0x4a, 0xc6, 0xea, 0xb6, 0x23, 0xb8, 0x9a, 0x4d, 0x71,
+	0x64, 0x42, 0x16, 0x69, 0xd1, 0xac, 0x76, 0xa2, 0x45, 0xd2, 0x86, 0x2d, 0x69, 0x6c, 0x10, 0x39,
+	0xeb, 0x60, 0xc5, 0x8f, 0x3b, 0x32, 0x0a, 0x8d, 0x90, 0x01, 0x47, 0x99, 0x22, 0xa2, 0x96, 0xad,
+	0xe4, 0x84, 0x65, 0xd2, 0x08, 0xf9, 0xe8, 0x47, 0xd8, 0xbb, 0x71, 0x11, 0x20, 0x75, 0xf8, 0x5f,
+	0xef, 0xb0, 0x7f, 0x3c, 0xec, 0x1d, 0xbe, 0xec, 0xda, 0x03, 0x7a, 0x76, 0x7e, 0xd6, 0x39, 0x7b,
+	0x65, 0xbf, 0xee, 0x0f, 0x07, 0xdd, 0xce, 0xe9, 0xc9, 0x69, 0xf7, 0xb8, 0xb2, 0x41, 0xb6, 0x21,
+	0x7b, 0xfe, 0x6a, 0x58, 0xb1, 0x48, 0x1e, 0x72, 0x87, 0xaf, 0xce, 0x87, 0x95, 0xcc, 0xa3, 0x2e,
+	0x94, 0x97, 0x6e, 0x48, 0xa4, 0x06, 0xf7, 0xfb, 0xdd, 0xf3, 0x5f, 0xce, 0xe8, 0xcb, 0x0f, 0xc5,
+	0xe9, 0x0c, 0x2a, 0x56, 0xf0, 0xf0, 0xfa, 0x78, 0x50, 0xc9, 0xb4, 0xdf, 0x2c, 0xa4, 0x24, 0x87,
+	0xe1, 0x85, 0x89, 0x9c, 0x40, 0xe1, 0x58, 0x24, 0xcb, 0xe4, 0xee, 0x6a, 0x39, 0x2e, 0x0f, 0xaa,
+	0x6b, 0x74, 0xf2, 0xeb, 0x1b, 0x0d, 0xeb, 0x2b, 0xeb, 0x68, 0x02, 0x77, 0x5c, 0x11, 0x62, 0x98,
+	0xa7, 0x55, 0xd3, 0xe5, 0x1a, 0x25, 0x67, 0xde, 0x51, 0x39, 0x85, 0x9b, 0xec, 0x07, 0xd6, 0xaf,
+	0xcf, 0xc7, 0x42, 0x8c, 0x3d, 0x6c, 0x8e, 0x85, 0xc7, 0xf8, 0xb8, 0x29, 0xe4, 0xb8, 0x65, 0xae,
+	0xa1, 0x8e, 0x44, 0x63, 0x5c, 0xe6, 0xa9, 0x56, 0x10, 0xa4, 0x15, 0x07, 0x69, 0x99, 0x53, 0x67,
+	0x40, 0xf6, 0xd8, 0xf1, 0xdf, 0x6e, 0x99, 0xf7, 0xc7, 0xff, 0x06, 0x00, 0x00, 0xff, 0xff, 0xe6,
+	0xde, 0x21, 0x9d, 0xe3, 0x0a, 0x00, 0x00,
 }
diff --git a/credentials/alts/core/proto/grpc_gcp/transport_security_common.pb.go b/credentials/alts/internal/proto/grpc_gcp/transport_security_common.pb.go
similarity index 71%
rename from credentials/alts/core/proto/grpc_gcp/transport_security_common.pb.go
rename to credentials/alts/internal/proto/grpc_gcp/transport_security_common.pb.go
index 120700ea..27510d4d 100644
--- a/credentials/alts/core/proto/grpc_gcp/transport_security_common.pb.go
+++ b/credentials/alts/internal/proto/grpc_gcp/transport_security_common.pb.go
@@ -1,7 +1,7 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // source: grpc/gcp/transport_security_common.proto
 
-package grpc_gcp // import "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+package grpc_gcp // import "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 
 import proto "github.com/golang/protobuf/proto"
 import fmt "fmt"
@@ -43,7 +43,7 @@ func (x SecurityLevel) String() string {
 	return proto.EnumName(SecurityLevel_name, int32(x))
 }
 func (SecurityLevel) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_transport_security_common_6489ab913bf26255, []int{0}
+	return fileDescriptor_transport_security_common_71945991f2c3b4a6, []int{0}
 }
 
 // Max and min supported RPC protocol versions.
@@ -61,7 +61,7 @@ func (m *RpcProtocolVersions) Reset()         { *m = RpcProtocolVersions{} }
 func (m *RpcProtocolVersions) String() string { return proto.CompactTextString(m) }
 func (*RpcProtocolVersions) ProtoMessage()    {}
 func (*RpcProtocolVersions) Descriptor() ([]byte, []int) {
-	return fileDescriptor_transport_security_common_6489ab913bf26255, []int{0}
+	return fileDescriptor_transport_security_common_71945991f2c3b4a6, []int{0}
 }
 func (m *RpcProtocolVersions) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RpcProtocolVersions.Unmarshal(m, b)
@@ -108,7 +108,7 @@ func (m *RpcProtocolVersions_Version) Reset()         { *m = RpcProtocolVersions
 func (m *RpcProtocolVersions_Version) String() string { return proto.CompactTextString(m) }
 func (*RpcProtocolVersions_Version) ProtoMessage()    {}
 func (*RpcProtocolVersions_Version) Descriptor() ([]byte, []int) {
-	return fileDescriptor_transport_security_common_6489ab913bf26255, []int{0, 0}
+	return fileDescriptor_transport_security_common_71945991f2c3b4a6, []int{0, 0}
 }
 func (m *RpcProtocolVersions_Version) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_RpcProtocolVersions_Version.Unmarshal(m, b)
@@ -149,30 +149,30 @@ func init() {
 }
 
 func init() {
-	proto.RegisterFile("grpc/gcp/transport_security_common.proto", fileDescriptor_transport_security_common_6489ab913bf26255)
+	proto.RegisterFile("grpc/gcp/transport_security_common.proto", fileDescriptor_transport_security_common_71945991f2c3b4a6)
 }
 
-var fileDescriptor_transport_security_common_6489ab913bf26255 = []byte{
-	// 324 bytes of a gzipped FileDescriptorProto
+var fileDescriptor_transport_security_common_71945991f2c3b4a6 = []byte{
+	// 323 bytes of a gzipped FileDescriptorProto
 	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x91, 0x41, 0x4b, 0x3b, 0x31,
 	0x10, 0xc5, 0xff, 0x5b, 0xf8, 0xab, 0x44, 0x56, 0xeb, 0x6a, 0x41, 0xc5, 0x83, 0x08, 0x42, 0xf1,
-	0x90, 0x05, 0xc5, 0x93, 0xa7, 0xb6, 0x16, 0x29, 0xd4, 0x6d, 0xdd, 0xd6, 0x42, 0xbd, 0x84, 0x18,
-	0x43, 0x88, 0x64, 0x33, 0x61, 0x36, 0x96, 0xfa, 0x95, 0xfd, 0x14, 0xb2, 0x69, 0x97, 0x22, 0x78,
-	0xf1, 0x96, 0xf7, 0x98, 0xf9, 0x4d, 0x66, 0x1e, 0x69, 0x2b, 0x74, 0x22, 0x55, 0xc2, 0xa5, 0x1e,
-	0xb9, 0x2d, 0x1d, 0xa0, 0x67, 0xa5, 0x14, 0x1f, 0xa8, 0xfd, 0x27, 0x13, 0x50, 0x14, 0x60, 0xa9,
-	0x43, 0xf0, 0x90, 0xec, 0x54, 0x95, 0x54, 0x09, 0x77, 0xf1, 0x15, 0x91, 0xc3, 0xdc, 0x89, 0x71,
-	0x65, 0x0b, 0x30, 0x33, 0x89, 0xa5, 0x06, 0x5b, 0x26, 0x8f, 0x64, 0xbf, 0xe0, 0x4b, 0x86, 0x4e,
-	0xb0, 0xc5, 0xca, 0x3b, 0x8e, 0xce, 0xa3, 0xf6, 0xee, 0xf5, 0x25, 0xad, 0x7b, 0xe9, 0x2f, 0x7d,
-	0x74, 0xfd, 0xc8, 0xe3, 0x82, 0x2f, 0x73, 0x27, 0xd6, 0x32, 0xe0, 0xb4, 0xfd, 0x81, 0x6b, 0xfc,
-	0x0d, 0xa7, 0xed, 0x06, 0x77, 0x7a, 0x4b, 0xb6, 0x6b, 0xf2, 0x11, 0xf9, 0x5f, 0xf0, 0x77, 0xc0,
-	0xf0, 0xbd, 0x38, 0x5f, 0x89, 0xe0, 0x6a, 0x0b, 0x18, 0xa6, 0x54, 0x6e, 0x25, 0xae, 0x9e, 0x48,
-	0x3c, 0x59, 0xdf, 0x63, 0x28, 0x17, 0xd2, 0x24, 0x07, 0x24, 0x9e, 0xf4, 0x7b, 0xcf, 0xf9, 0x60,
-	0x3a, 0x67, 0xd9, 0x28, 0xeb, 0x37, 0xff, 0x25, 0x09, 0xd9, 0x1b, 0x64, 0xd3, 0xfe, 0x43, 0xf0,
-	0x46, 0xd9, 0x70, 0xde, 0x8c, 0x92, 0x13, 0xd2, 0xda, 0x78, 0x9d, 0xec, 0x9e, 0x8d, 0xf3, 0xc1,
-	0xac, 0xd3, 0x9b, 0x37, 0x1b, 0x5d, 0x4f, 0x5a, 0x1a, 0x56, 0x3b, 0x70, 0xe3, 0x4b, 0xaa, 0xad,
-	0x97, 0x68, 0xb9, 0xe9, 0x9e, 0x4d, 0xeb, 0x0c, 0xea, 0x91, 0xbd, 0x90, 0x40, 0x58, 0x71, 0x1c,
-	0xbd, 0xdc, 0x29, 0x00, 0x65, 0x24, 0x55, 0x60, 0xb8, 0x55, 0x14, 0x50, 0xa5, 0x21, 0x3e, 0x81,
-	0xf2, 0x4d, 0x5a, 0xaf, 0xb9, 0x29, 0xd3, 0x8a, 0x98, 0x0a, 0x40, 0x99, 0x86, 0xd8, 0x42, 0x01,
-	0x53, 0xc2, 0xbd, 0x6e, 0x05, 0x7d, 0xf3, 0x1d, 0x00, 0x00, 0xff, 0xff, 0xa8, 0xc8, 0x38, 0x9d,
-	0xf2, 0x01, 0x00, 0x00,
+	0x90, 0x05, 0xc5, 0xb3, 0xb4, 0xb5, 0x48, 0xa1, 0x6e, 0xeb, 0xb6, 0x16, 0xea, 0x25, 0xc4, 0x18,
+	0x42, 0x24, 0x9b, 0x09, 0xb3, 0xb1, 0xd4, 0xaf, 0xec, 0xa7, 0x90, 0x4d, 0xbb, 0x14, 0xc1, 0x8b,
+	0xb7, 0xbc, 0xc7, 0xcc, 0x6f, 0x32, 0xf3, 0x48, 0x5b, 0xa1, 0x13, 0xa9, 0x12, 0x2e, 0xf5, 0xc8,
+	0x6d, 0xe9, 0x00, 0x3d, 0x2b, 0xa5, 0xf8, 0x40, 0xed, 0x3f, 0x99, 0x80, 0xa2, 0x00, 0x4b, 0x1d,
+	0x82, 0x87, 0x64, 0xa7, 0xaa, 0xa4, 0x4a, 0xb8, 0x8b, 0xaf, 0x88, 0x1c, 0xe6, 0x4e, 0x8c, 0x2b,
+	0x5b, 0x80, 0x99, 0x49, 0x2c, 0x35, 0xd8, 0x32, 0x79, 0x24, 0xfb, 0x05, 0x5f, 0x32, 0x74, 0x82,
+	0x2d, 0x56, 0xde, 0x71, 0x74, 0x1e, 0xb5, 0x77, 0xaf, 0x2f, 0x69, 0xdd, 0x4b, 0x7f, 0xe9, 0xa3,
+	0xeb, 0x47, 0x1e, 0x17, 0x7c, 0x99, 0x3b, 0xb1, 0x96, 0x01, 0xa7, 0xed, 0x0f, 0x5c, 0xe3, 0x6f,
+	0x38, 0x6d, 0x37, 0xb8, 0xd3, 0x5b, 0xb2, 0x5d, 0x93, 0x8f, 0xc8, 0xff, 0x82, 0xbf, 0x03, 0x86,
+	0xef, 0xc5, 0xf9, 0x4a, 0x04, 0x57, 0x5b, 0xc0, 0x30, 0xa5, 0x72, 0x2b, 0x71, 0xf5, 0x44, 0xe2,
+	0xc9, 0xfa, 0x1e, 0x43, 0xb9, 0x90, 0x26, 0x39, 0x20, 0xf1, 0xa4, 0xdf, 0x7b, 0xce, 0x07, 0xd3,
+	0x39, 0xcb, 0x46, 0x59, 0xbf, 0xf9, 0x2f, 0x49, 0xc8, 0xde, 0x20, 0x9b, 0xf6, 0x1f, 0x82, 0x37,
+	0xca, 0x86, 0xf3, 0x66, 0x94, 0x9c, 0x90, 0xd6, 0xc6, 0xeb, 0x64, 0xf7, 0x6c, 0x9c, 0x0f, 0x66,
+	0x9d, 0xde, 0xbc, 0xd9, 0xe8, 0x2e, 0x49, 0x4b, 0xc3, 0x6a, 0x07, 0x6e, 0x7c, 0x49, 0xb5, 0xf5,
+	0x12, 0x2d, 0x37, 0xdd, 0xb3, 0x69, 0x9d, 0x41, 0x3d, 0xb2, 0x17, 0x12, 0x08, 0x2b, 0x8e, 0xa3,
+	0x97, 0x3b, 0x05, 0xa0, 0x8c, 0xa4, 0x0a, 0x0c, 0xb7, 0x8a, 0x02, 0xaa, 0x34, 0xc4, 0x27, 0x50,
+	0xbe, 0x49, 0xeb, 0x35, 0x37, 0x65, 0x5a, 0x11, 0xd3, 0x9a, 0x98, 0x86, 0xe8, 0x42, 0x11, 0x53,
+	0xc2, 0xbd, 0x6e, 0x05, 0x7d, 0xf3, 0x1d, 0x00, 0x00, 0xff, 0xff, 0x31, 0x14, 0xb4, 0x11, 0xf6,
+	0x01, 0x00, 0x00,
 }
diff --git a/credentials/alts/core/regenerate.sh b/credentials/alts/internal/regenerate.sh
similarity index 100%
rename from credentials/alts/core/regenerate.sh
rename to credentials/alts/internal/regenerate.sh
diff --git a/credentials/alts/core/testutil/testutil.go b/credentials/alts/internal/testutil/testutil.go
similarity index 98%
rename from credentials/alts/core/testutil/testutil.go
rename to credentials/alts/internal/testutil/testutil.go
index 91cbd039..e114719d 100644
--- a/credentials/alts/core/testutil/testutil.go
+++ b/credentials/alts/internal/testutil/testutil.go
@@ -26,7 +26,7 @@ import (
 	"net"
 	"sync"
 
-	"google.golang.org/grpc/credentials/alts/core/conn"
+	"google.golang.org/grpc/credentials/alts/internal/conn"
 )
 
 // Stats is used to collect statistics about concurrent handshake calls.
diff --git a/credentials/alts/utils_test.go b/credentials/alts/utils_test.go
index dceae7a8..73bb62d8 100644
--- a/credentials/alts/utils_test.go
+++ b/credentials/alts/utils_test.go
@@ -24,7 +24,7 @@ import (
 	"testing"
 
 	"golang.org/x/net/context"
-	altspb "google.golang.org/grpc/credentials/alts/core/proto/grpc_gcp"
+	altspb "google.golang.org/grpc/credentials/alts/internal/proto/grpc_gcp"
 	"google.golang.org/grpc/peer"
 )