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package configfile
type flagIota int
const (
// FlagPlaintextNames indicates that filenames are unencrypted.
FlagPlaintextNames flagIota = iota
// FlagDirIV indicates that a per-directory IV file is used.
FlagDirIV
// FlagEMENames indicates EME (ECB-Mix-ECB) filename encryption.
// This flag is mandatory since gocryptfs v1.0.
FlagEMENames
// FlagGCMIV128 indicates 128-bit GCM IVs.
// This flag is mandatory since gocryptfs v1.0.
FlagGCMIV128
// FlagLongNames allows file names longer than 176 bytes.
FlagLongNames
// FlagAESSIV selects an AES-SIV based crypto backend.
FlagAESSIV
// FlagRaw64 enables raw (unpadded) base64 encoding for file names
FlagRaw64
// FlagHKDF enables HKDF-derived keys for use with GCM, EME and SIV
// instead of directly using the master key (GCM and EME) or the SHA-512
// hashed master key (SIV).
// Note that this flag does not change the password hashing algorithm
// which always is scrypt.
FlagHKDF
)
// knownFlags stores the known feature flags and their string representation
var knownFlags = map[flagIota]string{
FlagPlaintextNames: "PlaintextNames",
FlagDirIV: "DirIV",
FlagEMENames: "EMENames",
FlagGCMIV128: "GCMIV128",
FlagLongNames: "LongNames",
FlagAESSIV: "AESSIV",
FlagRaw64: "Raw64",
FlagHKDF: "HKDF",
}
// Filesystems that do not have these feature flags set are deprecated.
var requiredFlagsNormal = []flagIota{
FlagDirIV,
FlagEMENames,
FlagGCMIV128,
}
// Filesystems without filename encryption obviously don't have or need the
// filename related feature flags.
var requiredFlagsPlaintextNames = []flagIota{
FlagGCMIV128,
}
// isFeatureFlagKnown verifies that we understand a feature flag.
func (cf *ConfFile) isFeatureFlagKnown(flag string) bool {
for _, knownFlag := range knownFlags {
if knownFlag == flag {
return true
}
}
return false
}
// IsFeatureFlagSet returns true if the feature flag "flagWant" is enabled.
func (cf *ConfFile) IsFeatureFlagSet(flagWant flagIota) bool {
flagString := knownFlags[flagWant]
for _, flag := range cf.FeatureFlags {
if flag == flagString {
return true
}
}
return false
}
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