From 87d3ed9187cb9caccaa8df0769d4cb722cc5bd00 Mon Sep 17 00:00:00 2001 From: Jesse Dunietz Date: Sat, 6 Oct 2018 15:49:33 -0400 Subject: Add option for autounmount Even though filesystem notifications aren't implemented for FUSE, I decided to try my hand at implementing the autounmount feature (#128). I based it on the EncFS autounmount code, which records filesystem accesses and checks every X seconds whether it's idled long enough to unmount. I've tested the feature locally, but I haven't added any tests for this flag. I also haven't worked with Go before. So please let me know if there's anything that should be done differently. One particular concern: I worked from the assumption that the open files table is unique per-filesystem. If that's not true, I'll need to add an open file count and associated lock to the Filesystem type instead. https://github.com/rfjakob/gocryptfs/pull/265 --- internal/fusefrontend/fs.go | 5 +++++ internal/fusefrontend/names.go | 6 ++++++ 2 files changed, 11 insertions(+) (limited to 'internal/fusefrontend') diff --git a/internal/fusefrontend/fs.go b/internal/fusefrontend/fs.go index 1b6941e..c0d6151 100644 --- a/internal/fusefrontend/fs.go +++ b/internal/fusefrontend/fs.go @@ -47,6 +47,11 @@ type FS struct { // "gocryptfs -fsck" reads from the channel to also catch these transparently- // mitigated corruptions. MitigatedCorruptions chan string + // Track accesses to the filesystem so that we can know when to autounmount. + // An access is considered to have happened on every call to encryptPath, + // which is called as part of every filesystem operation. + // (This flag uses a uint32 so that it can be reset with CompareAndSwapUint32.) + AccessedSinceLastCheck uint32 } var _ pathfs.FileSystem = &FS{} // Verify that interface is implemented. diff --git a/internal/fusefrontend/names.go b/internal/fusefrontend/names.go index 5530e3e..3bf64d5 100644 --- a/internal/fusefrontend/names.go +++ b/internal/fusefrontend/names.go @@ -60,9 +60,15 @@ func (fs *FS) openBackingDir(relPath string) (dirfd int, cName string, err error // encryptPath - encrypt relative plaintext path func (fs *FS) encryptPath(plainPath string) (string, error) { + if plainPath != "" { // Empty path gets encrypted all the time without actual file accesses. + fs.AccessedSinceLastCheck = 1 + } else { // Empty string gets encrypted as empty string + return plainPath, nil + } if fs.args.PlaintextNames { return plainPath, nil } + fs.dirIVLock.RLock() cPath, err := fs.nameTransform.EncryptPathDirIV(plainPath, fs.args.Cipherdir) tlog.Debug.Printf("encryptPath '%s' -> '%s' (err: %v)", plainPath, cPath, err) -- cgit v1.2.3