libgocryptfs: update to gocryptfs v2.3

go.mod

@@ -1,14 +1,17 @@
 module libgocryptfs/v2
 
-go 1.16
+go 1.19
 
 require (
 	github.com/jacobsa/crypto v0.0.0-20190317225127-9f44e2d11115
+	github.com/rfjakob/eme v1.1.2
+	golang.org/x/crypto v0.0.0-20220829220503-c86fa9a7ed90
+	golang.org/x/sys v0.0.0-20220915200043-7b5979e65e41
+)
+
+require (
 	github.com/jacobsa/oglematchers v0.0.0-20150720000706-141901ea67cd // indirect
 	github.com/jacobsa/oglemock v0.0.0-20150831005832-e94d794d06ff // indirect
 	github.com/jacobsa/ogletest v0.0.0-20170503003838-80d50a735a11 // indirect
 	github.com/jacobsa/reqtrace v0.0.0-20150505043853-245c9e0234cb // indirect
-	github.com/rfjakob/eme v1.1.2
-	golang.org/x/crypto v0.0.0-20220214200702-86341886e292
-	golang.org/x/sys v0.0.0-20220227234510-4e6760a101f9
 )

go.sum

@@ -10,15 +10,8 @@ github.com/jacobsa/reqtrace v0.0.0-20150505043853-245c9e0234cb h1:uSWBjJdMf47kQl
 github.com/jacobsa/reqtrace v0.0.0-20150505043853-245c9e0234cb/go.mod h1:ivcmUvxXWjb27NsPEaiYK7AidlZXS7oQ5PowUS9z3I4=
 github.com/rfjakob/eme v1.1.2 h1:SxziR8msSOElPayZNFfQw4Tjx/Sbaeeh3eRvrHVMUs4=
 github.com/rfjakob/eme v1.1.2/go.mod h1:cVvpasglm/G3ngEfcfT/Wt0GwhkuO32pf/poW6Nyk1k=
-golang.org/x/crypto v0.0.0-20220214200702-86341886e292 h1:f+lwQ+GtmgoY+A2YaQxlSOnDjXcQ7ZRLWOHbC6HtRqE=
+golang.org/x/crypto v0.0.0-20220829220503-c86fa9a7ed90 h1:Y/gsMcFOcR+6S6f3YeMKl5g+dZMEWqcz5Czj/GWYbkM=
-golang.org/x/crypto v0.0.0-20220214200702-86341886e292/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
+golang.org/x/crypto v0.0.0-20220829220503-c86fa9a7ed90/go.mod h1:IxCIyHEi3zRg3s0A5j5BB6A9Jmi73HwBIUl50j+osU4=
 golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2 h1:CIJ76btIcR3eFI5EgSo6k1qKw9KJexJuRLI9G7Hp5wE=
-golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/sys v0.0.0-20220915200043-7b5979e65e41 h1:ohgcoMbSofXygzo6AD2I1kz3BFmW1QArPYTtwEM3UXc=
-golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20220915200043-7b5979e65e41/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220227234510-4e6760a101f9 h1:nhht2DYV/Sn3qOayu8lM+cU1ii9sTLUeBQwQQfUHtrs=
-golang.org/x/sys v0.0.0-20220227234510-4e6760a101f9/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

internal/configfile/config_file.go

@@ -54,6 +54,8 @@ type ConfFile struct {
 	FeatureFlags []string
 	// FIDO2 parameters
 	FIDO2 *FIDO2Params `json:",omitempty"`
+	// LongNameMax corresponds to the -longnamemax flag
+	LongNameMax uint8 `json:",omitempty"`
 	// Filename is the name of the config file. Not exported to JSON.
 	filename string
 }
@@ -68,6 +70,7 @@ type CreateArgs struct {
 	AESSIV             bool
 	DeterministicNames bool
 	XChaCha20Poly1305  bool
+	LongNameMax        uint8
 }
 
 // Create - create a new config with a random key encrypted with
@@ -94,6 +97,12 @@ func Create(args *CreateArgs, returnedScryptHashBuff []byte) error {
 		if !args.DeterministicNames {
 			cf.setFeatureFlag(FlagDirIV)
 		}
+		// 0 means to *use* the default (which means we don't have to save it), and
+		// 255 *is* the default, which means we don't have to save it either.
+		if args.LongNameMax != 0 && args.LongNameMax != 255 {
+			cf.LongNameMax = args.LongNameMax
+			cf.setFeatureFlag(FlagLongNameMax)
+		}
 		cf.setFeatureFlag(FlagEMENames)
 		cf.setFeatureFlag(FlagLongNames)
 		cf.setFeatureFlag(FlagRaw64)

internal/configfile/feature_flags.go

@@ -14,8 +14,11 @@ const (
 	// This flag is mandatory since gocryptfs v1.0,
 	// except when XChaCha20Poly1305 is used.
 	FlagGCMIV128
-	// FlagLongNames allows file names longer than 176 bytes.
+	// FlagLongNames allows file names longer than 175 bytes.
 	FlagLongNames
+	// FlagLongNameMax sets a custom name length limit, names longer than that
+	// will be hashed.
+	FlagLongNameMax
 	// FlagAESSIV selects an AES-SIV based crypto backend.
 	FlagAESSIV
 	// FlagRaw64 enables raw (unpadded) base64 encoding for file names
@@ -40,6 +43,7 @@ var knownFlags = map[flagIota]string{
 	FlagEMENames:          "EMENames",
 	FlagGCMIV128:          "GCMIV128",
 	FlagLongNames:         "LongNames",
+	FlagLongNameMax:       "LongNameMax",
 	FlagAESSIV:            "AESSIV",
 	FlagRaw64:             "Raw64",
 	FlagHKDF:              "HKDF",

internal/configfile/validate.go

@@ -23,22 +23,23 @@ func (cf *ConfFile) Validate() error {
 	}
 	// File content encryption
 	{
-		switch {
+		if cf.IsFeatureFlagSet(FlagXChaCha20Poly1305) && cf.IsFeatureFlagSet(FlagAESSIV) {
-		case cf.IsFeatureFlagSet(FlagXChaCha20Poly1305) && cf.IsFeatureFlagSet(FlagAESSIV):
 			return fmt.Errorf("Can't have both XChaCha20Poly1305 and AESSIV feature flags")
-		case cf.IsFeatureFlagSet(FlagAESSIV):
+		}
-			if !cf.IsFeatureFlagSet(FlagGCMIV128) {
+		if cf.IsFeatureFlagSet(FlagAESSIV) && !cf.IsFeatureFlagSet(FlagGCMIV128) {
+
 			return fmt.Errorf("AESSIV requires GCMIV128 feature flag")
 		}
-		case cf.IsFeatureFlagSet(FlagXChaCha20Poly1305):
+		if cf.IsFeatureFlagSet(FlagXChaCha20Poly1305) {
 			if cf.IsFeatureFlagSet(FlagGCMIV128) {
 				return fmt.Errorf("XChaCha20Poly1305 conflicts with GCMIV128 feature flag")
 			}
 			if !cf.IsFeatureFlagSet(FlagHKDF) {
 				return fmt.Errorf("XChaCha20Poly1305 requires HKDF feature flag")
 			}
+		}
 		// The absence of other flags means AES-GCM (oldest algorithm)
-		case !cf.IsFeatureFlagSet(FlagXChaCha20Poly1305) && !cf.IsFeatureFlagSet(FlagAESSIV):
+		if !cf.IsFeatureFlagSet(FlagXChaCha20Poly1305) && !cf.IsFeatureFlagSet(FlagAESSIV) {
 			if !cf.IsFeatureFlagSet(FlagGCMIV128) {
 				return fmt.Errorf("AES-GCM requires GCMIV128 feature flag")
 			}
@@ -46,10 +47,10 @@ func (cf *ConfFile) Validate() error {
 	}
 	// Filename encryption
 	{
-		switch {
+		if cf.IsFeatureFlagSet(FlagPlaintextNames) {
-		case cf.IsFeatureFlagSet(FlagPlaintextNames) && cf.IsFeatureFlagSet(FlagEMENames):
+			if cf.IsFeatureFlagSet(FlagEMENames) {
-			return fmt.Errorf("Can't have both PlaintextNames and EMENames feature flags")
+				return fmt.Errorf("PlaintextNames conflicts with EMENames feature flag")
-		case cf.IsFeatureFlagSet(FlagPlaintextNames):
+			}
 			if cf.IsFeatureFlagSet(FlagDirIV) {
 				return fmt.Errorf("PlaintextNames conflicts with DirIV feature flag")
 			}
@@ -59,9 +60,19 @@ func (cf *ConfFile) Validate() error {
 			if cf.IsFeatureFlagSet(FlagRaw64) {
 				return fmt.Errorf("PlaintextNames conflicts with Raw64 feature flag")
 			}
-		case cf.IsFeatureFlagSet(FlagEMENames):
+			if cf.IsFeatureFlagSet(FlagLongNameMax) {
+				return fmt.Errorf("PlaintextNames conflicts with LongNameMax feature flag")
+			}
+		}
+		if cf.IsFeatureFlagSet(FlagEMENames) {
 			// All combinations of DirIV, LongNames, Raw64 allowed
 		}
+		if cf.LongNameMax != 0 && !cf.IsFeatureFlagSet(FlagLongNameMax) {
+			return fmt.Errorf("LongNameMax=%d but the LongNameMax feature flag is NOT set", cf.LongNameMax)
+		}
+		if cf.LongNameMax == 0 && cf.IsFeatureFlagSet(FlagLongNameMax) {
+			return fmt.Errorf("LongNameMax=0 but the LongNameMax feature flag IS set")
+		}
 	}
 	return nil
 }

internal/nametransform/badname.go

@@ -34,7 +34,7 @@ func (be *NameTransform) EncryptAndHashBadName(name string, iv []byte, dirfd int
 		//file found, return result
 		return lastFoundName, nil
 	}
-	//BadName Mode: check if the name was tranformed without change (badname suffix and undecryptable cipher name)
+	//BadName Mode: check if the name was transformed without change (badname suffix and undecryptable cipher name)
 	err = syscallcompat.Fstatat(dirfd, name[:len(name)-len(BadnameSuffix)], &st, unix.AT_SYMLINK_NOFOLLOW)
 	if err == nil {
 		filesFound++
@@ -48,7 +48,7 @@ func (be *NameTransform) EncryptAndHashBadName(name string, iv []byte, dirfd int
 			//expand suffix on error
 			continue
 		}
-		if be.longNames && len(cName) > NameMax {
+		if len(cName) > be.longNameMax {
 			cNamePart = be.HashLongName(cName)
 		}
 		cNameBadReverse := cNamePart + name[charpos:len(name)-len(BadnameSuffix)]

internal/nametransform/names.go

@@ -4,6 +4,7 @@ package nametransform
 import (
 	"crypto/aes"
 	"encoding/base64"
+	"math"
 	"path/filepath"
 	"syscall"
 
@@ -18,7 +19,9 @@ const (
 // NameTransform is used to transform filenames.
 type NameTransform struct {
 	emeCipher *eme.EMECipher
-	longNames bool
+	// Names longer than `longNameMax` are hashed. Set to MaxInt when
+	// longnames are disabled.
+	longNameMax int
 	// B64 = either base64.URLEncoding or base64.RawURLEncoding, depending
 	// on the Raw64 feature flag
 	B64 *base64.Encoding
@@ -28,14 +31,26 @@ type NameTransform struct {
 }
 
 // New returns a new NameTransform instance.
-func New(e *eme.EMECipher, longNames bool, raw64 bool, badname []string, deterministicNames bool) *NameTransform {
+//
+// If `longNames` is set, names longer than `longNameMax` are hashed to
+// `gocryptfs.longname.[sha256]`.
+// Pass `longNameMax = 0` to use the default value (255).
+func New(e *eme.EMECipher, longNames bool, longNameMax uint8, raw64 bool, badname []string, deterministicNames bool) *NameTransform {
 	b64 := base64.URLEncoding
 	if raw64 {
 		b64 = base64.RawURLEncoding
 	}
+	var effectiveLongNameMax int = math.MaxInt32
+	if longNames {
+		if longNameMax == 0 {
+			effectiveLongNameMax = NameMax
+		} else {
+			effectiveLongNameMax = int(longNameMax)
+		}
+	}
 	return &NameTransform{
 		emeCipher:          e,
-		longNames:          longNames,
+		longNameMax:        effectiveLongNameMax,
 		B64:                b64,
 		badnamePatterns:    badname,
 		deterministicNames: deterministicNames,
@@ -47,7 +62,13 @@ func New(e *eme.EMECipher, longNames bool, raw64 bool, badname []string, determi
 func (n *NameTransform) DecryptName(cipherName string, iv []byte) (string, error) {
 	res, err := n.decryptName(cipherName, iv)
 	if err != nil && n.HaveBadnamePatterns() {
-		return n.decryptBadname(cipherName, iv)
+		res, err = n.decryptBadname(cipherName, iv)
+	}
+	if err != nil {
+		return "", err
+	}
+	if err := IsValidName(res); err != nil {
+		return "", syscall.EBADMSG
 	}
 	return res, err
 }
@@ -71,26 +92,34 @@ func (n *NameTransform) decryptName(cipherName string, iv []byte) (string, error
 		return "", syscall.EBADMSG
 	}
 	plain := string(bin)
-	if err := IsValidName(plain); err != nil {
-		return "", syscall.EBADMSG
-	}
 	return plain, err
 }
 
-// EncryptName encrypts "plainName", returns a base64-encoded "cipherName64",
+// EncryptName encrypts a file name "plainName" and returns a base64-encoded "cipherName64",
 // encrypted using EME (https://github.com/rfjakob/eme).
 //
+// plainName is checked for null bytes, slashes etc. and such names are rejected
+// with an error.
+//
 // This function is exported because in some cases, fusefrontend needs access
 // to the full (not hashed) name if longname is used.
 func (n *NameTransform) EncryptName(plainName string, iv []byte) (cipherName64 string, err error) {
 	if err := IsValidName(plainName); err != nil {
 		return "", syscall.EBADMSG
 	}
+	return n.encryptName(plainName, iv), nil
+}
+
+// encryptName encrypts "plainName" and returns a base64-encoded "cipherName64",
+// encrypted using EME (https://github.com/rfjakob/eme).
+//
+// No checks for null bytes etc are performed against plainName.
+func (n *NameTransform) encryptName(plainName string, iv []byte) (cipherName64 string) {
 	bin := []byte(plainName)
 	bin = pad16(bin)
 	bin = n.emeCipher.Encrypt(iv, bin)
 	cipherName64 = n.B64.EncodeToString(bin)
-	return cipherName64, nil
+	return cipherName64
 }
 
 // EncryptAndHashName encrypts "name" and hashes it to a longname if it is
@@ -105,7 +134,7 @@ func (be *NameTransform) EncryptAndHashName(name string, iv []byte) (string, err
 	if err != nil {
 		return "", err
 	}
-	if be.longNames && len(cName) > NameMax {
+	if len(cName) > be.longNameMax {
 		return be.HashLongName(cName), nil
 	}
 	return cName, nil
@@ -129,3 +158,9 @@ func Dir(path string) string {
 	}
 	return d
 }
+
+// GetLongNameMax will return curent `longNameMax`. File name longer than
+// this should be hashed.
+func (n *NameTransform) GetLongNameMax() int {
+	return n.longNameMax
+}

internal/stupidgcm/chacha.go

@@ -1,3 +1,4 @@
+//go:build !without_openssl
 // +build !without_openssl
 
 package stupidgcm

internal/stupidgcm/common.go

@@ -1,3 +1,4 @@
+//go:build !without_openssl
 // +build !without_openssl
 
 package stupidgcm

internal/stupidgcm/gcm.go

@@ -1,3 +1,4 @@
+//go:build !without_openssl
 // +build !without_openssl
 
 package stupidgcm

internal/stupidgcm/locking.go

@@ -1,3 +1,4 @@
+//go:build !without_openssl
 // +build !without_openssl
 
 package stupidgcm

internal/stupidgcm/openssl.go

@@ -1,3 +1,4 @@
+//go:build !without_openssl
 // +build !without_openssl
 
 package stupidgcm
@@ -117,7 +118,7 @@ func slicePointerOrNull(s []byte) (ptr *C.uchar) {
 }
 
 // This functions exists to benchmark the C call overhead from Go.
-// See BenchmarkCCall for resuts.
+// See BenchmarkCCall for results.
 func noopCFunction() {
 	C.noop_c_function()
 }

internal/stupidgcm/prefer.go

@@ -40,7 +40,7 @@ func PreferOpenSSLXchacha20poly1305() bool {
 	if runtime.GOARCH == "amd64" {
 		return false
 	}
-	// On arm64 and arm, OpenSSL is faster. Probably everwhere else too.
+	// On arm64 and arm, OpenSSL is faster. Probably everywhere else too.
 	return true
 }
 

internal/stupidgcm/xchacha.go

@@ -1,3 +1,4 @@
+//go:build !without_openssl
 // +build !without_openssl
 
 // Copyright 2018 The Go Authors. All rights reserved.

internal/syscallcompat/getdents_linux.go

@@ -1,3 +1,4 @@
+//go:build linux
 // +build linux
 
 package syscallcompat

internal/syscallcompat/sys_linux.go

@@ -17,8 +17,10 @@ const (
 	// O_PATH is only defined on Linux
 	O_PATH = unix.O_PATH
 
-	// RENAME_NOREPLACE is only defined on Linux
+	// Only defined on Linux
 	RENAME_NOREPLACE = unix.RENAME_NOREPLACE
+	RENAME_WHITEOUT  = unix.RENAME_WHITEOUT
+	RENAME_EXCHANGE  = unix.RENAME_EXCHANGE
 )
 
 // EnospcPrealloc preallocates ciphertext space without changing the file

volume.go

@@ -9,6 +9,7 @@ import (
 	"sync"
 	"syscall"
 	"path/filepath"
+	"runtime/debug"
 
 	"libgocryptfs/v2/internal/configfile"
 	"libgocryptfs/v2/internal/contentenc"
@@ -81,6 +82,7 @@ func registerNewVolume(rootCipherDir string, masterkey []byte, cf *configfile.Co
 	newVolume.nameTransform = nametransform.New(
 		newVolume.cryptoCore.EMECipher,
 		true,
+		cf.LongNameMax,
 		cf.IsFeatureFlagSet(configfile.FlagRaw64),
 		badname,
 		!cf.IsFeatureFlagSet(configfile.FlagDirIV),
@@ -116,6 +118,8 @@ func gcf_init(rootCipherDir string, password, givenScryptHash, returnedScryptHas
 	cf, err := configfile.Load(filepath.Join(rootCipherDir, configfile.ConfDefaultName))
 	if err == nil {
 		masterkey := cf.GetMasterkey(password, givenScryptHash, returnedScryptHashBuff)
+		wipe(password)
+		debug.FreeOSMemory()
 		if masterkey != nil {
 			volumeID = registerNewVolume(rootCipherDir, masterkey, cf)
 			wipe(masterkey)
@@ -152,14 +156,14 @@ func gcf_is_closed(volumeID int) bool {
 }
 
 //export gcf_change_password
-func gcf_change_password(rootCipherDir string, oldPassword, givenScryptHash, new_password, returnedScryptHashBuff []byte) bool {
+func gcf_change_password(rootCipherDir string, oldPassword, givenScryptHash, newPassword, returnedScryptHashBuff []byte) bool {
 	success := false
 	cf, err := configfile.Load(filepath.Join(rootCipherDir, configfile.ConfDefaultName))
 	if err == nil {
 		masterkey := cf.GetMasterkey(oldPassword, givenScryptHash, nil)
 		if masterkey != nil {
 			logN := cf.ScryptObject.LogN()
-			scryptHash := cf.EncryptKey(masterkey, new_password, logN, len(returnedScryptHashBuff) > 0)
+			scryptHash := cf.EncryptKey(masterkey, newPassword, logN, len(returnedScryptHashBuff) > 0)
 			wipe(masterkey)
 			for i := range scryptHash {
 				returnedScryptHashBuff[i] = scryptHash[i]
@@ -168,6 +172,9 @@ func gcf_change_password(rootCipherDir string, oldPassword, givenScryptHash, new
 			success = errToBool(cf.WriteFile())
 		}
 	}
+	wipe(newPassword)
+	wipe(oldPassword)
+	wipe(givenScryptHash)
 	return success
 }
 
@@ -191,7 +198,9 @@ func gcf_create_volume(rootCipherDir string, password []byte, plaintextNames boo
 		AESSIV:             false,
 		DeterministicNames: false,
 		XChaCha20Poly1305:  useXChaCha,
+		LongNameMax:        255,
 	}, returnedScryptHashBuff)
+	wipe(password)
 	if err == nil {
 		if plaintextNames {
 			return true