diff options
| -rw-r--r-- | pkg/sentry/fsimpl/verity/filesystem.go | 2 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/verity/verity.go | 32 | ||||
| -rw-r--r-- | pkg/sentry/fsimpl/verity/verity_test.go | 10 |
3 files changed, 26 insertions, 18 deletions
diff --git a/pkg/sentry/fsimpl/verity/filesystem.go b/pkg/sentry/fsimpl/verity/filesystem.go index 04e7110a3..a4ad625bb 100644 --- a/pkg/sentry/fsimpl/verity/filesystem.go +++ b/pkg/sentry/fsimpl/verity/filesystem.go @@ -163,7 +163,7 @@ afterSymlink: // verifyChildLocked verifies the hash of child against the already verified // hash of the parent to ensure the child is expected. verifyChild triggers a // sentry panic if unexpected modifications to the file system are detected. In -// noCrashOnVerificationFailure mode it returns a syserror instead. +// ErrorOnViolation mode it returns a syserror instead. // // Preconditions: // * fs.renameMu must be locked. diff --git a/pkg/sentry/fsimpl/verity/verity.go b/pkg/sentry/fsimpl/verity/verity.go index 9563ceab4..66029c64d 100644 --- a/pkg/sentry/fsimpl/verity/verity.go +++ b/pkg/sentry/fsimpl/verity/verity.go @@ -92,10 +92,8 @@ const ( ) var ( - // noCrashOnVerificationFailure indicates whether the sandbox should panic - // whenever verification fails. If true, an error is returned instead of - // panicking. This should only be set for tests. - noCrashOnVerificationFailure bool + // action specifies the action towards detected violation. + action ViolationAction // verityMu synchronizes concurrent operations that enable verity and perform // verification checks. @@ -106,6 +104,18 @@ var ( // content. type HashAlgorithm int +// ViolationAction is a type specifying the action when an integrity violation +// is detected. +type ViolationAction int + +const ( + // PanicOnViolation terminates the sentry on detected violation. + PanicOnViolation ViolationAction = 0 + // ErrorOnViolation returns an error from the violating system call on + // detected violation. + ErrorOnViolation = 1 +) + // Currently supported hashing algorithms include SHA256 and SHA512. const ( SHA256 HashAlgorithm = iota @@ -200,10 +210,8 @@ type InternalFilesystemOptions struct { // system wrapped by verity file system. LowerGetFSOptions vfs.GetFilesystemOptions - // NoCrashOnVerificationFailure indicates whether the sandbox should - // panic whenever verification fails. If true, an error is returned - // instead of panicking. This should only be set for tests. - NoCrashOnVerificationFailure bool + // Action specifies the action on an integrity violation. + Action ViolationAction } // Name implements vfs.FilesystemType.Name. @@ -215,10 +223,10 @@ func (FilesystemType) Name() string { func (FilesystemType) Release(ctx context.Context) {} // alertIntegrityViolation alerts a violation of integrity, which usually means -// unexpected modification to the file system is detected. In -// noCrashOnVerificationFailure mode, it returns EIO, otherwise it panic. +// unexpected modification to the file system is detected. In ErrorOnViolation +// mode, it returns EIO, otherwise it panic. func alertIntegrityViolation(msg string) error { - if noCrashOnVerificationFailure { + if action == ErrorOnViolation { return syserror.EIO } panic(msg) @@ -231,7 +239,7 @@ func (fstype FilesystemType) GetFilesystem(ctx context.Context, vfsObj *vfs.Virt ctx.Warningf("verity.FilesystemType.GetFilesystem: missing verity configs") return nil, nil, syserror.EINVAL } - noCrashOnVerificationFailure = iopts.NoCrashOnVerificationFailure + action = iopts.Action // Mount the lower file system. The lower file system is wrapped inside // verity, and should not be exposed or connected. diff --git a/pkg/sentry/fsimpl/verity/verity_test.go b/pkg/sentry/fsimpl/verity/verity_test.go index bd948715f..30d8b4355 100644 --- a/pkg/sentry/fsimpl/verity/verity_test.go +++ b/pkg/sentry/fsimpl/verity/verity_test.go @@ -92,11 +92,11 @@ func newVerityRoot(t *testing.T, hashAlg HashAlgorithm) (*vfs.VirtualFilesystem, mntns, err := vfsObj.NewMountNamespace(ctx, auth.CredentialsFromContext(ctx), "", "verity", &vfs.MountOptions{ GetFilesystemOptions: vfs.GetFilesystemOptions{ InternalData: InternalFilesystemOptions{ - RootMerkleFileName: rootMerkleFilename, - LowerName: "tmpfs", - Alg: hashAlg, - AllowRuntimeEnable: true, - NoCrashOnVerificationFailure: true, + RootMerkleFileName: rootMerkleFilename, + LowerName: "tmpfs", + Alg: hashAlg, + AllowRuntimeEnable: true, + Action: ErrorOnViolation, }, }, }) |