Note: This page is horribly out of
date.
You can find the current pages for the dm-crypt
project (the Linux kernel part) here:
https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt
and the project page for the command line tool
cryptsetup (with Linux Unified Key
Setup - LUKS) here: https://gitlab.com/cryptsetup/cryptsetup.
Old page:
Device-mapper is a new infrastructure in the Linux 2.6 kernel that provides
a generic way to create virtual layers of block devices that can do different
things on top of real block devices like striping, concatenation, mirroring,
snapshotting, etc... The device-mapper is used by the
LVM2 and
EVMS 2.x tools.
dm-crypt is such a device-mapper target that provides transparent encryption of
block devices using the new Linux 2.6 cryptoapi. The user can basically specify
one of the symmetric ciphers, a key (of any allowed size), an iv generation mode
and then the user can create a new block device in /dev. Writes to this device
will be encrypted and reads decrypted. You can mount your filesystem on it as usual.
But without the key you can't access your data.
It does basically the same as cryptoloop only that it's a much cleaner code and
better suits the need of a block device and has a more flexible configuration
interface. The on-disk format is also compatible. In the future you will be able
to specify other iv generation modes for enhanced security (you'll have to
reencrypt your filesystem though).
I've set up a Wiki.
There's a mailing list at .
If you want to subscribe, use the mailman
web interface or its
archive.
Gmane provides a NNTP interface and also a
web archive
for this mailing list.
There is support for dm-crypt in the latest official kernel
2.6.4
which you can find on kernel.org.
Please use the mirrors for downloads.
There is a HIGHMEM cryptoapi bug in kernels before 2.6.4-rc2, please
upgrade if you were using such a kernel.
The latest version of the native userspace setup tool is cryptsetup 0.1.
Clemens Fruhwirth is maintaining an
enhanced
version of cryptsetup with the LUKS extension that allows you to have an
on-disk block of metadata which is superior to the current mechanism and was
my long term plan anyway but I didn't find the time to implement that yet...
A solid red light usually indicates an incompatible firmware version or a failed flash. You must repeat the USB pinout method to flash a compatible firmware repair package.
This is widely considered the safest method, as it involves no firmware changes.
Power the device off for 30 seconds and then back on to clear the temporary cache.
using custom firmware lets you bypass strict carrier locks, access hidden network settings, and pick any data provider worldwide. Many units come locked to specific providers, like Free Libyana or Vodafone, turning your device into an expensive paperweight if you change networks.
Flashing firmware can damage your router if done incorrectly. Proceed with caution and ensure the router is not turned off during the process. Risks and Precautions
Select your computer’s network card from the network adapter dropdown list.
If your router's default firmware allows manual code entry, an IMEI unlock is the safest method as it does not carry any risk of bricking the device. Step 1: Locate Your Router's IMEI
: Navigate to 192.168.8.1 in your browser and log in with your admin credentials.
Unlike simple "unlock codes" that work for older devices, modern LTE routers like the B311221 often require a firmware flash to remove the carrier lock. Here is why unlocking the firmware is the best route:
If you have installed custom firmware, you can now explore the advanced features, such as enabling Telnet, setting up ad-blocking, or configuring a VPN.
These tools often require a paid license (like credits for DC-Unlocker) but offer a graphical interface or straightforward command-line instructions.
hardware, explains the advantages of flashing modded exclusive firmware, and provides a clear walkthrough for safely unlocking your router. 📊 Technical Profiles: Huawei B311-221 Huawei B311-221
The on-disk layouts used by the current 2.6 cryptoloop are supported by dm-crypt.
Cryptoloop also uses cryptoapi so the name of the ciphers are the same. Cryptoloop also
supports ECB and CBC mode. Use <cipher>-ecb and
<cipher>-plain accordingly with dm-crypt. If you didn't
explicitly specify either -ecb or -cbc before you don't need it now, the default plain
IV generation will be used. There will be additional (incompatible, but more secure) possibilites
in the future because the unhashed sector number as IV is too predictible.
You'll need to figure out how your passphrase was turned into a key to use for losetup.
There are several patches floating around doing things differently. But usually cryptsetup
will provide a working solution to recreate the same key from your passphrase.
If you want to migrate from 2.4 cryptoloop please take a look at Clemens Fruhwirth's
Cryptoloop
Migration Guide. He describes the differences between 2.4 and 2.6 cryptoapi (or basically
the bugs in 2.4 cryptoapi...). If you need to cut the key size you can use the -s
option instead of playing with dd.
(BTW: Clemens has a i586 optimized version of the aes and serpent cipher on his page,
about twice as fast as the kernel implementation.)
Why dm-crypt?
Originally it started as a fun project because I wanted to play with the new Linux 2.6 internals.
I got a lot of great help from the device-mapper guys at Sistina (now Redhat). Thank you very
much!
It turned out that this implementation worked great and is very clean compared to the hacked
loop device. The device-mapper core provides much better facilities to stack block devices.
dm-crypt uses mempools to assure we never run into out-of-memory deadlocks when allocating
buffers.
Also the device-mapper configuration interface provides much more flexibility than the losetup
ioctl. And you can create as many devices as you want with any names you want and combine them
with other dm targets. Online device resizing is also possible, e.g. if you use dm-crypt on top
of a logical volume. There might perhaps even be LVM or EVMS support for device encryption
in the future.
A solid red light usually indicates an incompatible firmware version or a failed flash. You must repeat the USB pinout method to flash a compatible firmware repair package.
This is widely considered the safest method, as it involves no firmware changes.
Power the device off for 30 seconds and then back on to clear the temporary cache.
using custom firmware lets you bypass strict carrier locks, access hidden network settings, and pick any data provider worldwide. Many units come locked to specific providers, like Free Libyana or Vodafone, turning your device into an expensive paperweight if you change networks. huawei router b311221 unlock firmware exclusive
Flashing firmware can damage your router if done incorrectly. Proceed with caution and ensure the router is not turned off during the process. Risks and Precautions
Select your computer’s network card from the network adapter dropdown list.
If your router's default firmware allows manual code entry, an IMEI unlock is the safest method as it does not carry any risk of bricking the device. Step 1: Locate Your Router's IMEI A solid red light usually indicates an incompatible
: Navigate to 192.168.8.1 in your browser and log in with your admin credentials.
Unlike simple "unlock codes" that work for older devices, modern LTE routers like the B311221 often require a firmware flash to remove the carrier lock. Here is why unlocking the firmware is the best route:
If you have installed custom firmware, you can now explore the advanced features, such as enabling Telnet, setting up ad-blocking, or configuring a VPN. Power the device off for 30 seconds and
These tools often require a paid license (like credits for DC-Unlocker) but offer a graphical interface or straightforward command-line instructions.
hardware, explains the advantages of flashing modded exclusive firmware, and provides a clear walkthrough for safely unlocking your router. 📊 Technical Profiles: Huawei B311-221 Huawei B311-221
Please contact the mailing list: dm-crypt@saout.de. Or in case there is a problem with the mailing list, me: .