1.. SPDX-License-Identifier: GPL-2.0 2 3====================================================== 4eCryptfs: A stacked cryptographic filesystem for Linux 5====================================================== 6 7eCryptfs is free software. Please see the file COPYING for details. 8For documentation, please see the files in the doc/ subdirectory. For 9building and installation instructions please see the INSTALL file. 10 11:Maintainer: Phillip Hellewell 12:Lead developer: Michael A. Halcrow <mhalcrow@us.ibm.com> 13:Developers: Michael C. Thompson 14 Kent Yoder 15:Web Site: http://ecryptfs.sf.net 16 17This software is currently undergoing development. Make sure to 18maintain a backup copy of any data you write into eCryptfs. 19 20eCryptfs requires the userspace tools downloadable from the 21SourceForge site: 22 23http://sourceforge.net/projects/ecryptfs/ 24 25Userspace requirements include: 26 27- David Howells' userspace keyring headers and libraries (version 28 1.0 or higher), obtainable from 29 http://people.redhat.com/~dhowells/keyutils/ 30- Libgcrypt 31 32 33.. note:: 34 35 In the beta/experimental releases of eCryptfs, when you upgrade 36 eCryptfs, you should copy the files to an unencrypted location and 37 then copy the files back into the new eCryptfs mount to migrate the 38 files. 39 40 41Mount-wide Passphrase 42===================== 43 44Create a new directory into which eCryptfs will write its encrypted 45files (i.e., /root/crypt). Then, create the mount point directory 46(i.e., /mnt/crypt). Now it's time to mount eCryptfs:: 47 48 mount -t ecryptfs /root/crypt /mnt/crypt 49 50You should be prompted for a passphrase and a salt (the salt may be 51blank). 52 53Try writing a new file:: 54 55 echo "Hello, World" > /mnt/crypt/hello.txt 56 57The operation will complete. Notice that there is a new file in 58/root/crypt that is at least 12288 bytes in size (depending on your 59host page size). This is the encrypted underlying file for what you 60just wrote. To test reading, from start to finish, you need to clear 61the user session keyring: 62 63keyctl clear @u 64 65Then umount /mnt/crypt and mount again per the instructions given 66above. 67 68:: 69 70 cat /mnt/crypt/hello.txt 71 72 73Notes 74===== 75 76eCryptfs version 0.1 should only be mounted on (1) empty directories 77or (2) directories containing files only created by eCryptfs. If you 78mount a directory that has pre-existing files not created by eCryptfs, 79then behavior is undefined. Do not run eCryptfs in higher verbosity 80levels unless you are doing so for the sole purpose of debugging or 81development, since secret values will be written out to the system log 82in that case. 83 84 85Mike Halcrow 86mhalcrow@us.ibm.com 87