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Diffstat (limited to 'Documentation/SECURITY.md')
| -rw-r--r-- | Documentation/SECURITY.md | 48 |
1 files changed, 1 insertions, 47 deletions
diff --git a/Documentation/SECURITY.md b/Documentation/SECURITY.md index a49994a..47edd1d 100644 --- a/Documentation/SECURITY.md +++ b/Documentation/SECURITY.md @@ -1,47 +1 @@ -GoCryptFS Security -================== - -Master Key Storage ------------------- - -The master key is used to perform content and file name encryption. -It is stored in `gocryptfs.conf`, encrypted with AES-256-GCM using the -Key Encryption Key (KEK). - -The KEK is generated from the user password using `scrypt`. - - - -File Contents -------------- - -All file contents are encrypted using AES-256-GCM (Galois/Counter Mode). - -Files are segmented into 4KB blocks. Each block gets a fresh random -128 bit IV each time it is modified. A 128-bit authentication tag (GHASH) -protects each block from modifications. - -Each file has a header containing a random 128-bit file ID. The -file ID and the block number are mixed into the GHASH as -*additional authenticated data*. The prevents blocks from being copied -between or within files. - - - -To support sparse files, all-zero blocks are accepted and passed through -unchanged. - -File Names ----------- - -Every directory gets a 128-bit directory IV that is stored in each -directory as `gocryptfs.diriv`. - -File names are encrypted using AES-256-EME (ECB-Mix-ECB wide-block encryption, -see https://github.com/rfjakob/eme for details) with the directory IV -as initialization vector. EME fixes the prefix leak that occours with CBC -encryption. - - - -The Base64 encoding limits the usable filename length to 176 characters. +This page has been moved to https://nuetzlich.net/gocryptfs/security/ . |