Cryptmount is a utility for GNU/Linux operating systems which allows an ordinary user to mount an encrypted filing system without requiring superuser privileges. It is aimed at recent Linux systems using the 2.6 kernel series.
Cryptmount was written to make it as easy for ordinary users to access encrypted filesystems on-demand using the newer devmapper mechansism as it was to use the older, now deprecated, cryptoloop methods. This offers the following advantages:
- access to improved functionality in the kernel
- transparent support for filesystems stored on either raw disk partitions or loopback files
- separate encryption of filesystem access keys, allowing access passwords to be changed without re-encrypting the entire filesystem
- storing multiple encrypted filesystems within a single disk partition, using a designated subset of blocks for each
- rarely used filesystems do not need to be mounted at system startup
- un-mounting of each filesystem is locked so that this can only be performed by the user that mounted it, or the superuser
- encrypted filesystems compatible with cryptsetup
- encrypted access-keys can be chosen to be compatible with openssl, or managed via libgcrypt, or (for 2.0 release-series) built-in SHA1/Blowfish ciphers
- support for encrypted swap partitions (superuser only)
- support for setting up encrypted filesystems or crypto-swap at system boot-up.