aboutsummaryrefslogtreecommitdiff
path: root/internal
diff options
context:
space:
mode:
authorJakob Unterwurzacher2021-08-02 20:01:26 +0200
committerJakob Unterwurzacher2021-08-02 20:01:26 +0200
commitc3c9513e6504276698ed1f50a259d4333476acf8 (patch)
treef5cf3a6cf76dc36ebf04c5eaa365f80355fa0494 /internal
parent75cf36fe7b4e64379ba67804d8c5ac56e25f63b7 (diff)
fusefrontend: add quirks for MacOS ExFAT
This also moves the quirks logic into fusefrontend. Fixes https://github.com/rfjakob/gocryptfs/issues/585
Diffstat (limited to 'internal')
-rw-r--r--internal/fusefrontend/file.go2
-rw-r--r--internal/fusefrontend/node_helpers.go2
-rw-r--r--internal/fusefrontend/quirks.go52
-rw-r--r--internal/fusefrontend/root_node.go4
4 files changed, 58 insertions, 2 deletions
diff --git a/internal/fusefrontend/file.go b/internal/fusefrontend/file.go
index 4866e65..304ba7f 100644
--- a/internal/fusefrontend/file.go
+++ b/internal/fusefrontend/file.go
@@ -118,7 +118,7 @@ func (f *File) createHeader() (fileID []byte, err error) {
h := contentenc.RandomHeader()
buf := h.Pack()
// Prevent partially written (=corrupt) header by preallocating the space beforehand
- if !f.rootNode.args.NoPrealloc {
+ if !f.rootNode.args.NoPrealloc && f.rootNode.quirks&quirkBrokenFalloc == 0 {
err = syscallcompat.EnospcPrealloc(f.intFd(), 0, contentenc.HeaderLen)
if err != nil {
if !syscallcompat.IsENOSPC(err) {
diff --git a/internal/fusefrontend/node_helpers.go b/internal/fusefrontend/node_helpers.go
index 31954f3..2f361f6 100644
--- a/internal/fusefrontend/node_helpers.go
+++ b/internal/fusefrontend/node_helpers.go
@@ -87,7 +87,7 @@ func (n *Node) newChild(ctx context.Context, st *syscall.Stat_t, out *fuse.Entry
out.Attr.FromStat(st)
var gen uint64 = 1
- if rn.args.SharedStorage {
+ if rn.args.SharedStorage || rn.quirks&quirkDuplicateIno1 != 0 {
// Make each directory entry a unique node by using a unique generation
// value - see the comment at RootNode.gen for details.
gen = atomic.AddUint64(&rn.gen, 1)
diff --git a/internal/fusefrontend/quirks.go b/internal/fusefrontend/quirks.go
new file mode 100644
index 0000000..2979c84
--- /dev/null
+++ b/internal/fusefrontend/quirks.go
@@ -0,0 +1,52 @@
+package fusefrontend
+
+import (
+ "runtime"
+
+ "golang.org/x/sys/unix"
+
+ "github.com/rfjakob/gocryptfs/internal/tlog"
+)
+
+const (
+ quirkBrokenFalloc = uint64(1 << iota)
+ quirkDuplicateIno1
+)
+
+func detectQuirks(cipherdir string) (q uint64) {
+ const (
+ // From Linux' man statfs
+ BTRFS_SUPER_MAGIC = 0x9123683e
+
+ // From https://github.com/rfjakob/gocryptfs/issues/585#issuecomment-887370065
+ DARWIN_EXFAT_MAGIC = 35
+ )
+
+ var st unix.Statfs_t
+ err := unix.Statfs(cipherdir, &st)
+ if err != nil {
+ tlog.Warn.Printf("detectQuirks: Statfs on %q failed: %v", cipherdir, err)
+ return 0
+ }
+
+ logQuirk := func(s string) {
+ tlog.Info.Printf(tlog.ColorYellow + "detectQuirks: " + s + tlog.ColorReset)
+ }
+
+ // Preallocation on Btrfs is broken ( https://github.com/rfjakob/gocryptfs/issues/395 )
+ // and slow ( https://github.com/rfjakob/gocryptfs/issues/63 ).
+ //
+ // Cast to uint32 avoids compile error on arm: "constant 2435016766 overflows int32"
+ if uint32(st.Type) == BTRFS_SUPER_MAGIC {
+ logQuirk("Btrfs detected, forcing -noprealloc. See https://github.com/rfjakob/gocryptfs/issues/395 for why.")
+ q |= quirkBrokenFalloc
+ }
+ // On MacOS ExFAT, all empty files share inode number 1:
+ // https://github.com/rfjakob/gocryptfs/issues/585
+ if runtime.GOOS == "darwin" && st.Type == DARWIN_EXFAT_MAGIC {
+ logQuirk("ExFAT detected, disabling hard links. See https://github.com/rfjakob/gocryptfs/issues/585 for why.")
+ q |= quirkDuplicateIno1
+ }
+
+ return q
+}
diff --git a/internal/fusefrontend/root_node.go b/internal/fusefrontend/root_node.go
index 46bee4a..9905d66 100644
--- a/internal/fusefrontend/root_node.go
+++ b/internal/fusefrontend/root_node.go
@@ -57,6 +57,9 @@ type RootNode struct {
// makes go-fuse hand out separate FUSE Node IDs for each, and prevents
// bizarre problems when inode numbers are reused behind our back.
gen uint64
+ // quirks is a bitmap that enables workaround for quirks in the filesystem
+ // backing the cipherdir
+ quirks uint64
}
func NewRootNode(args Args, c *contentenc.ContentEnc, n *nametransform.NameTransform) *RootNode {
@@ -76,6 +79,7 @@ func NewRootNode(args Args, c *contentenc.ContentEnc, n *nametransform.NameTrans
contentEnc: c,
inoMap: inomap.New(),
dirCache: dirCache{ivLen: ivLen},
+ quirks: detectQuirks(args.Cipherdir),
}
return rn
}