Documentation
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Overview ¶
Package filesystem deals with the structure of the files on disk used to store the metadata for fscrypt. Specifically, this package includes:
- mountpoint management (mountpoint.go)
- querying existing mounted filesystems
- getting filesystems from a UUID
- finding the filesystem for a specific path
- metadata organization (filesystem.go)
- setting up a mounted filesystem for use with fscrypt
- adding/querying/deleting metadata
- making links to other filesystems' metadata
- following links to get data from other filesystems
Index ¶
- Variables
- func UpdateMountInfo() error
- type Mount
- func (m *Mount) AddLinkedProtector(descriptor string, dest *Mount) error
- func (m *Mount) AddPolicy(data *metadata.PolicyData) error
- func (m *Mount) AddProtector(data *metadata.ProtectorData) error
- func (m *Mount) BaseDir() string
- func (m *Mount) CheckSetup() error
- func (m *Mount) CheckSupport() error
- func (m *Mount) GetPolicy(descriptor string) (*metadata.PolicyData, error)
- func (m *Mount) GetProtector(descriptor string) (*Mount, *metadata.ProtectorData, error)
- func (m *Mount) GetRegularProtector(descriptor string) (*metadata.ProtectorData, error)
- func (m *Mount) ListPolicies() ([]string, error)
- func (m *Mount) ListProtectors() ([]string, error)
- func (m *Mount) PolicyDir() string
- func (m *Mount) ProtectorDir() string
- func (m *Mount) RemoveAllMetadata() error
- func (m *Mount) RemovePolicy(descriptor string) error
- func (m *Mount) RemoveProtector(descriptor string) error
- func (m *Mount) Setup() error
- func (m *Mount) String() string
- type PathSorter
Constants ¶
This section is empty.
Variables ¶
var ( ErrNotAMountpoint = errors.New("not a mountpoint") ErrAlreadySetup = errors.New("already setup for use with fscrypt") ErrNotSetup = errors.New("not setup for use with fscrypt") ErrNoMetadata = errors.New("could not find metadata") ErrLinkedProtector = errors.New("not a regular protector") ErrInvalidMetadata = errors.New("provided metadata is invalid") ErrFollowLink = errors.New("cannot follow filesystem link") ErrLinkExpired = errors.New("no longer exists on linked filesystem") ErrMakeLink = util.SystemError("cannot create filesystem link") ErrGlobalMountInfo = util.SystemError("creating global mountpoint list failed") ErrCorruptMetadata = util.SystemError("on-disk metadata is corrupt") )
Filesystem error values
Functions ¶
func UpdateMountInfo ¶
func UpdateMountInfo() error
UpdateMountInfo updates the filesystem mountpoint maps with the current state of the filesystem mountpoints. Returns error if the initialization fails.
Types ¶
type Mount ¶
Mount contains information for a specific mounted filesystem.
Path - Absolute path where the directory is mounted Filesystem - Name of the mounted filesystem Options - List of options used when mounting the filesystem Device - Device for filesystem (empty string if we cannot find one)
In order to use a Mount to store fscrypt metadata, some directories must be setup first. Specifically, the directories created look like: <mountpoint> └── .fscrypt
├── policies └── protectors
These "policies" and "protectors" directories will contain files that are the corresponding metadata structures for policies and protectors. The public interface includes functions for setting up these directories and Adding, Getting, and Removing these files.
There is also the ability to reference another filesystem's metadata. This is used when a Policy on filesystem A is protected with Protector on filesystem B. In this scenario, we store a "link file" in the protectors directory whose contents look like "UUID=3a6d9a76-47f0-4f13-81bf-3332fbe984fb".
func AllFilesystems ¶
AllFilesystems lists all the Mounts on the current system ordered by path. Use CheckSetup() to see if they are used with fscrypt.
func FindMount ¶
FindMount returns the corresponding Mount object for some path in a filesystem. Note that in the case of a bind mounts there may be two Mount objects for the same underlying filesystem. An error is returned if the path is invalid or we cannot load the required mount data. If a filesystem has been updated since the last call to one of the mount functions, run UpdateMountInfo to see changes.
func GetMount ¶
GetMount returns the Mount object with a matching mountpoint. An error is returned if the path is invalid or we cannot load the required mount data. If a filesystem has been updated since the last call to one of the mount functions, run UpdateMountInfo to see changes.
func (*Mount) AddLinkedProtector ¶
AddLinkedProtector adds a link in this filesystem to the protector metadata in the dest filesystem.
func (*Mount) AddPolicy ¶
func (m *Mount) AddPolicy(data *metadata.PolicyData) error
AddPolicy adds the policy metadata to the filesystem storage.
func (*Mount) AddProtector ¶
func (m *Mount) AddProtector(data *metadata.ProtectorData) error
AddProtector adds the protector metadata to this filesystem's storage. This will overwrite the value of an existing protector with this descriptor. This will fail with ErrLinkedProtector if a linked protector with this descriptor already exists on the filesystem.
func (*Mount) CheckSetup ¶
CheckSetup returns an error if all the fscrypt metadata directories do not exist. Will log any unexpected errors or incorrect permissions.
func (*Mount) CheckSupport ¶ added in v0.2.0
CheckSupport returns an error if this filesystem does not support filesystem encryption.
func (*Mount) GetPolicy ¶
func (m *Mount) GetPolicy(descriptor string) (*metadata.PolicyData, error)
GetPolicy looks up the policy metadata by descriptor.
func (*Mount) GetProtector ¶
GetProtector returns the Mount of the filesystem containing the information and that protector's data. If the descriptor is a regular (not linked) protector, the mount will return itself.
func (*Mount) GetRegularProtector ¶
func (m *Mount) GetRegularProtector(descriptor string) (*metadata.ProtectorData, error)
GetRegularProtector looks up the protector metadata by descriptor. This will fail with ErrNoMetadata if the descriptor is a linked protector.
func (*Mount) ListPolicies ¶
ListPolicies lists the descriptors of all policies on this filesystem.
func (*Mount) ListProtectors ¶
ListProtectors lists the descriptors of all protectors on this filesystem. This does not include linked protectors.
func (*Mount) ProtectorDir ¶
ProtectorDir returns the directory containing the protector metadata.
func (*Mount) RemoveAllMetadata ¶
RemoveAllMetadata removes all the policy and protector metadata from the filesystem. This operation is atomic, it either succeeds or no files in the baseDir are removed. WARNING: Will cause data loss if the metadata is used to encrypt directories (this could include directories on other filesystems).
func (*Mount) RemovePolicy ¶
RemovePolicy deletes the policy metadata from the filesystem storage.
func (*Mount) RemoveProtector ¶
RemoveProtector deletes the protector metadata (or an link to another filesystem's metadata) from the filesystem storage.
type PathSorter ¶
type PathSorter []*Mount
PathSorter allows mounts to be sorted by Path.
func (PathSorter) Len ¶
func (p PathSorter) Len() int
func (PathSorter) Less ¶
func (p PathSorter) Less(i, j int) bool
func (PathSorter) Swap ¶
func (p PathSorter) Swap(i, j int)
Source Files