diff options
| author | Jakob Unterwurzacher | 2017-05-23 20:46:24 +0200 |
|---|---|---|
| committer | Jakob Unterwurzacher | 2017-05-23 21:26:38 +0200 |
| commit | e827763f2e6226d9f5778d56c28270264950c0f5 (patch) | |
| tree | 2f5f4adeed482dd473cc4714b97a8903806fdbb3 /internal/fusefrontend | |
| parent | 508fd9e1d64131958c86175cb8d848f730e629cf (diff) | |
nametransform: harden name decryption against invalid input
This fixes a few issues I have found reviewing the code:
1) Limit the amount of data ReadLongName() will read. Previously,
you could send gocryptfs into out-of-memory by symlinking
gocryptfs.diriv to /dev/zero.
2) Handle the empty input case in unPad16() by returning an
error. Previously, it would panic with an out-of-bounds array
read. It is unclear to me if this could actually be triggered.
3) Reject empty names after base64-decoding in DecryptName().
An empty name crashes emeCipher.Decrypt().
It is unclear to me if B64.DecodeString() can actually return
a non-error empty result, but let's guard against it anyway.
Diffstat (limited to 'internal/fusefrontend')
| -rw-r--r-- | internal/fusefrontend/fs_dir.go | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/internal/fusefrontend/fs_dir.go b/internal/fusefrontend/fs_dir.go index 7d1e3ef..30e715a 100644 --- a/internal/fusefrontend/fs_dir.go +++ b/internal/fusefrontend/fs_dir.go @@ -273,16 +273,14 @@ func (fs *FS) OpenDir(dirName string, context *fuse.Context) ([]fuse.DirEntry, f // silently ignore "gocryptfs.conf" in the top level dir continue } - if !fs.args.PlaintextNames && cName == nametransform.DirIVFilename { - // silently ignore "gocryptfs.diriv" everywhere if dirIV is enabled - continue - } - if fs.args.PlaintextNames { plain = append(plain, cipherEntries[i]) continue } - + if cName == nametransform.DirIVFilename { + // silently ignore "gocryptfs.diriv" everywhere if dirIV is enabled + continue + } // Handle long file name isLong := nametransform.LongNameNone if fs.args.LongNames { @@ -301,7 +299,6 @@ func (fs *FS) OpenDir(dirName string, context *fuse.Context) ([]fuse.DirEntry, f // ignore "gocryptfs.longname.*.name" continue } - name, err := fs.nameTransform.DecryptName(cName, cachedIV) if err != nil { tlog.Warn.Printf("OpenDir %q: invalid entry %q: %v", |