Merge pull request #346 from google/fixes

Metadata validation and other security improvements

3 files changed, 71 insertions, 59 deletions

diff --git a/metadata/config_test.go b/metadata/config_test.go
index 52f83f2..2874bb8 100644
--- a/metadata/config_test.go
+++ b/metadata/config_test.go
@@ -49,7 +49,8 @@ var testConfigString = `{
 		"filenames": "AES_256_CTS",
 		"policy_version": "1"
 	},
-	"use_fs_keyring_for_v1_policies": false
+	"use_fs_keyring_for_v1_policies": false,
+	"allow_cross_user_metadata": false
 }
 `
 
diff --git a/metadata/metadata.pb.go b/metadata/metadata.pb.go
index a2148ce..6709804 100644
--- a/metadata/metadata.pb.go
+++ b/metadata/metadata.pb.go
@@ -45,7 +45,7 @@ func (x SourceType) String() string {
 	return proto.EnumName(SourceType_name, int32(x))
 }
 func (SourceType) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{0}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{0}
 }
 
 // Type of encryption; should match declarations of unix.FSCRYPT_MODE
@@ -87,7 +87,7 @@ func (x EncryptionOptions_Mode) String() string {
 	return proto.EnumName(EncryptionOptions_Mode_name, int32(x))
 }
 func (EncryptionOptions_Mode) EnumDescriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{3, 0}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{3, 0}
 }
 
 // Cost parameters to be used in our hashing functions.
@@ -104,7 +104,7 @@ func (m *HashingCosts) Reset()         { *m = HashingCosts{} }
 func (m *HashingCosts) String() string { return proto.CompactTextString(m) }
 func (*HashingCosts) ProtoMessage()    {}
 func (*HashingCosts) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{0}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{0}
 }
 func (m *HashingCosts) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_HashingCosts.Unmarshal(m, b)
@@ -159,7 +159,7 @@ func (m *WrappedKeyData) Reset()         { *m = WrappedKeyData{} }
 func (m *WrappedKeyData) String() string { return proto.CompactTextString(m) }
 func (*WrappedKeyData) ProtoMessage()    {}
 func (*WrappedKeyData) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{1}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{1}
 }
 func (m *WrappedKeyData) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_WrappedKeyData.Unmarshal(m, b)
@@ -219,7 +219,7 @@ func (m *ProtectorData) Reset()         { *m = ProtectorData{} }
 func (m *ProtectorData) String() string { return proto.CompactTextString(m) }
 func (*ProtectorData) ProtoMessage()    {}
 func (*ProtectorData) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{2}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{2}
 }
 func (m *ProtectorData) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_ProtectorData.Unmarshal(m, b)
@@ -303,7 +303,7 @@ func (m *EncryptionOptions) Reset()         { *m = EncryptionOptions{} }
 func (m *EncryptionOptions) String() string { return proto.CompactTextString(m) }
 func (*EncryptionOptions) ProtoMessage()    {}
 func (*EncryptionOptions) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{3}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{3}
 }
 func (m *EncryptionOptions) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_EncryptionOptions.Unmarshal(m, b)
@@ -363,7 +363,7 @@ func (m *WrappedPolicyKey) Reset()         { *m = WrappedPolicyKey{} }
 func (m *WrappedPolicyKey) String() string { return proto.CompactTextString(m) }
 func (*WrappedPolicyKey) ProtoMessage()    {}
 func (*WrappedPolicyKey) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{4}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{4}
 }
 func (m *WrappedPolicyKey) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_WrappedPolicyKey.Unmarshal(m, b)
@@ -411,7 +411,7 @@ func (m *PolicyData) Reset()         { *m = PolicyData{} }
 func (m *PolicyData) String() string { return proto.CompactTextString(m) }
 func (*PolicyData) ProtoMessage()    {}
 func (*PolicyData) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{5}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{5}
 }
 func (m *PolicyData) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_PolicyData.Unmarshal(m, b)
@@ -458,6 +458,7 @@ type Config struct {
 	HashCosts                 *HashingCosts      `protobuf:"bytes,2,opt,name=hash_costs,json=hashCosts,proto3" json:"hash_costs,omitempty"`
 	Options                   *EncryptionOptions `protobuf:"bytes,4,opt,name=options,proto3" json:"options,omitempty"`
 	UseFsKeyringForV1Policies bool               `protobuf:"varint,5,opt,name=use_fs_keyring_for_v1_policies,json=useFsKeyringForV1Policies,proto3" json:"use_fs_keyring_for_v1_policies,omitempty"`
+	AllowCrossUserMetadata    bool               `protobuf:"varint,6,opt,name=allow_cross_user_metadata,json=allowCrossUserMetadata,proto3" json:"allow_cross_user_metadata,omitempty"`
 	XXX_NoUnkeyedLiteral      struct{}           `json:"-"`
 	XXX_unrecognized          []byte             `json:"-"`
 	XXX_sizecache             int32              `json:"-"`
@@ -467,7 +468,7 @@ func (m *Config) Reset()         { *m = Config{} }
 func (m *Config) String() string { return proto.CompactTextString(m) }
 func (*Config) ProtoMessage()    {}
 func (*Config) Descriptor() ([]byte, []int) {
-	return fileDescriptor_metadata_20fa0d9b7a38c428, []int{6}
+	return fileDescriptor_metadata_31965d2849cb292a, []int{6}
 }
 func (m *Config) XXX_Unmarshal(b []byte) error {
 	return xxx_messageInfo_Config.Unmarshal(m, b)
@@ -515,6 +516,13 @@ func (m *Config) GetUseFsKeyringForV1Policies() bool {
 	return false
 }
 
+func (m *Config) GetAllowCrossUserMetadata() bool {
+	if m != nil {
+		return m.AllowCrossUserMetadata
+	}
+	return false
+}
+
 func init() {
 	proto.RegisterType((*HashingCosts)(nil), "metadata.HashingCosts")
 	proto.RegisterType((*WrappedKeyData)(nil), "metadata.WrappedKeyData")
@@ -527,53 +535,55 @@ func init() {
 	proto.RegisterEnum("metadata.EncryptionOptions_Mode", EncryptionOptions_Mode_name, EncryptionOptions_Mode_value)
 }
 
-func init() { proto.RegisterFile("metadata/metadata.proto", fileDescriptor_metadata_20fa0d9b7a38c428) }
-
-var fileDescriptor_metadata_20fa0d9b7a38c428 = []byte{
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+func init() { proto.RegisterFile("metadata/metadata.proto", fileDescriptor_metadata_31965d2849cb292a) }
+
+var fileDescriptor_metadata_31965d2849cb292a = []byte{
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+	0x39, 0xb7, 0x7e, 0xf4, 0x87, 0xd0, 0x59, 0xd0, 0xf4, 0x39, 0x6d, 0x7b, 0x41, 0xd3, 0x0d, 0xc2,
+	0x53, 0xa8, 0xf1, 0x7c, 0x08, 0x05, 0xd9, 0xa7, 0x2f, 0xcc, 0x09, 0x97, 0xbe, 0xe8, 0x06, 0xde,
+	0x95, 0x75, 0x16, 0x83, 0x5a, 0xd0, 0x34, 0x1b, 0xb5, 0x75, 0xd4, 0x1c, 0x7c, 0xf2, 0xac, 0xde,
+	0x95, 0x26, 0x78, 0x77, 0xf9, 0x04, 0x91, 0xbd, 0x7f, 0x4d, 0xa8, 0x0e, 0x79, 0x34, 0x65, 0xb3,
+	0x8d, 0xb5, 0x33, 0x5e, 0xb1, 0x76, 0xa7, 0x00, 0x73, 0x22, 0xe7, 0x6e, 0xbe, 0x67, 0xe6, 0x8b,
+	0x7b, 0xd6, 0xc8, 0x3c, 0xf3, 0x7f, 0xb2, 0x8d, 0x96, 0x2b, 0x6f, 0x68, 0xf9, 0x1c, 0x3e, 0x4b,
+	0x24, 0x75, 0xa7, 0x32, 0x6b, 0x55, 0xb0, 0x68, 0xe6, 0x4e, 0xb9, 0x70, 0x1f, 0xfb, 0xb9, 0x00,
+	0x8c, 0x4a, 0xbd, 0xbc, 0x75, 0x7c, 0x90, 0x48, 0x7a, 0x25, 0x6f, 0x73, 0x9f, 0x2b, 0x2e, 0x26,
+	0xfd, 0xfb, 0xc2, 0x01, 0x9d, 0xc1, 0x01, 0x09, 0x02, 0xbe, 0x74, 0x3d, 0xc1, 0xa5, 0x74, 0x13,
+	0x49, 0x85, 0x5b, 0x52, 0xeb, 0x3d, 0xaf, 0xe3, 0x7d, 0xed, 0x30, 0xcc, 0xee, 0x7f, 0x91, 0x54,
+	0xdc, 0x15, 0xb7, 0x37, 0x95, 0xba, 0x65, 0x57, 0x70, 0xdb, 0xe3, 0x61, 0x4c, 0x14, 0x7b, 0x60,
+	0x01, 0x53, 0xe9, 0x17, 0x3f, 0x03, 0xac, 0x65, 0xd9, 0x5e, 0x02, 0x04, 0x9d, 0x98, 0x84, 0x6e,
+	0x4c, 0xa4, 0x8c, 0xe7, 0x82, 0x48, 0x6a, 0x1b, 0xe8, 0x23, 0xd8, 0xf5, 0x12, 0xa9, 0xf8, 0x16,
+	0x6c, 0x66, 0x71, 0x82, 0x2c, 0xb3, 0xae, 0x6c, 0xeb, 0xa1, 0xaa, 0xbf, 0x03, 0x5f, 0xfd, 0x1f,
+	0x00, 0x00, 0xff, 0xff, 0xe2, 0x78, 0x9e, 0x2e, 0x22, 0x06, 0x00, 0x00,
 }
diff --git a/metadata/metadata.proto b/metadata/metadata.proto
index 8ffb4f6..84245e0 100644
--- a/metadata/metadata.proto
+++ b/metadata/metadata.proto
@@ -99,6 +99,7 @@ message Config {
   HashingCosts hash_costs = 2;
   EncryptionOptions options = 4;
   bool use_fs_keyring_for_v1_policies = 5;
+  bool allow_cross_user_metadata = 6;
 
   // reserve the removed field 'string compatibility = 3;'
   reserved 3;