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5 Commits

Author SHA1 Message Date
4ee5965bfa added: retry pin 2022-01-24 14:36:07 +01:00
b939e9efcd added: allow-discards env var 2022-01-24 14:19:04 +01:00
f6c2bc4cdb added --allow-discards flag 2021-12-28 13:50:21 +01:00
4e7ef4b8b7 0.3.0-alpha notice 2021-12-11 11:52:40 +01:00
e1ad8b37c1 0.3.0-alpha 2021-12-11 11:51:07 +01:00
9 changed files with 40 additions and 319 deletions

4
Cargo.lock generated
View File

@@ -1,5 +1,7 @@
# This file is automatically @generated by Cargo. # This file is automatically @generated by Cargo.
# It is not intended for manual editing. # It is not intended for manual editing.
version = 3
[[package]] [[package]]
name = "addr2line" name = "addr2line"
version = "0.13.0" version = "0.13.0"
@@ -404,7 +406,7 @@ dependencies = [
[[package]] [[package]]
name = "fido2luks" name = "fido2luks"
version = "0.3.0" version = "0.3.0-alpha"
dependencies = [ dependencies = [
"ctap_hmac", "ctap_hmac",
"failure", "failure",

View File

@@ -1,6 +1,6 @@
[package] [package]
name = "fido2luks" name = "fido2luks"
version = "0.3.0" version = "0.3.0-alpha"
authors = ["shimunn <shimun@shimun.net>"] authors = ["shimunn <shimun@shimun.net>"]
edition = "2018" edition = "2018"

161
README.md
View File

@@ -1,160 +1,7 @@
# fido2luks [![Crates.io Version](https://img.shields.io/crates/v/fido2luks.svg)](https://crates.io/crates/fido2luks) # fido2luks [![Crates.io Version](https://img.shields.io/crates/v/fido2luks.svg)](https://crates.io/crates/fido2luks)
This will allow you to unlock your LUKS encrypted disk with an FIDO2 compatible key. ## 0.3.0-alpha
Note: This has only been tested under Fedora 31, [Ubuntu 20.04](initramfs-tools/), [NixOS](https://nixos.org/nixos/manual/#sec-luks-file-systems-fido2) using a Solo Key, Trezor Model T, YubiKey(fw >= [5.2.3](https://support.yubico.com/hc/en-us/articles/360016649319-YubiKey-5-2-3-Enhancements-to-FIDO-2-Support))
## Setup
### Prerequisites
```
dnf install clang cargo cryptsetup-devel -y
```
### Device
```
git clone https://github.com/shimunn/fido2luks.git && cd fido2luks
# Alternativly cargo build --release && sudo cp target/release/fido2luks /usr/bin/
sudo -E cargo install -f --path . --root /usr
# Copy template
cp dracut/96luks-2fa/fido2luks.conf /etc/
# Name is optional but useful if your authenticator has a display
echo FIDO2LUKS_CREDENTIAL_ID=$(fido2luks credential [NAME]) >> /etc/fido2luks.conf
# Load config into env
set -a
. /etc/fido2luks.conf
# Repeat for each luks volume
# You can also use the `--token` flag when using LUKS2 which will then store the credential in the LUKS header,
# enabling you to use `fido2luks open-token` without passing a credential as parameter
sudo -E fido2luks -i add-key /dev/disk/by-uuid/<DISK_UUID>
# Test(only works if the luks container isn't active)
sudo -E fido2luks -i open /dev/disk/by-uuid/<DISK_UUID> luks-<DISK_UUID>
```
### Dracut
```
cd dracut
sudo make install
```
### Grub
Add `rd.luks.2fa=<CREDENTIAL_ID>:<DISK_UUID>` to `GRUB_CMDLINE_LINUX` in /etc/default/grub
Note: This is only required for your root disk, systemd will try to unlock all other LUKS partions using the same key if you added it using `fido2luks add-key`
```
grub2-mkconfig > /boot/grub2/grub.cfg
```
I'd also recommend to copy the executable onto /boot so that it is accessible in case you have to access your disk from a rescue system
```
mkdir /boot/fido2luks/
cp /usr/bin/fido2luks /boot/fido2luks/
cp /etc/fido2luks.conf /boot/fido2luks/
```
## Testing
Just reboot and see if it works, if that's the case you should remove your old less secure password from your LUKS header:
```
# Recommend in case you lose your authenticator, store this backupfile somewhere safe
cryptsetup luksHeaderBackup /dev/disk/by-uuid/<DISK_UUID> --header-backup-file luks_backup_<DISK_UUID>
# There is no turning back if you mess this up, make sure you made a backup
# You can also pass `--token` if you're using LUKS2 which will then store the credential in the LUKS header,
# which will enable you to use `fido2luks open-token` without passing a credential as parameter
fido2luks -i add-key --exclusive /dev/disk/by-uuid/<DISK_UUID>
```
## Addtional settings
### Password less
Remove your previous secret as described in the next section, in case you've already added one.
Open `/etc/fido2luks.conf` and replace `FIDO2LUKS_SALT=Ask` with `FIDO2LUKS_SALT=string:<YOUR_RANDOM_STRING>`
but be warned that this password will be included to into your initramfs.
Import the new config into env:
```
set -a
. /etc/fido2luks.conf
```
Then add the new secret to each device and update dracut afterwards `dracut -f`
### Multiple keys
Additional/backup keys are supported, Multiple fido2luks credentials can be added to your /etc/fido2luks.conf file. Credential tokens are comma separated.
```
FIDO2LUKS_CREDENTIAL_ID=<CREDENTIAL1>,<CREDENTIAL2>,<CREDENTIAL3>
```
## Removal
Remove `rd.luks.2fa` from `GRUB_CMDLINE_LINUX` in /etc/default/grub
```
set -a
. fido2luks.conf
sudo -E fido2luks -i replace-key /dev/disk/by-uuid/<DISK_UUID>
sudo rm -rf /usr/lib/dracut/modules.d/96luks-2fa /etc/dracut.conf.d/luks-2fa.conf /etc/fido2luks.conf
```
## Theory of operation
fido2luks builds on two basic building blocks, LUKS as an abstraction over linux disk encryption and and the FIDO2 extension [`hmac-secret`](https://fidoalliance.org/specs/fido-v2.0-rd-20180702/fido-client-to-authenticator-protocol-v2.0-rd-20180702.html#sctn-hmac-secret-extension).
The `hmac-secret` extension allows for an secret to be dervied on the FIDO2 device from two inputs, the user supplied salt/password/keyfile and another secret contained within the FID2 device. The output of the `hmac-secret` function will then be used to decrypt the LUKS header which in turn is used to decrypt the disk.
```
+-------------------------------------------------------------------------------+
| |
| +-----------------------------------------+ |
| | FIDO2 device | |
| | | |
| | | |
+-------+--------+ +------+ | +---------------+ | | +------------------------+
| Salt/Password +-> |sha256+------------------------> | | | v | LUKS header |
+----------------+ +------+ | | | | | | +---------------+
| | | | +--------+ +------------------------+--------> |Disk master key|
| | sha256_hmac +---------> | sha256 +-------> | Keyslot 1 | +---------------+
+----------------+ | +----------+ | | | +--------+ +------------------------+
| FIDO credential+---------------> |Credential| +----> | | | | Keyslot 2 |
+----------------+ | |secret | | | | +------------------------+
| +----------+ +---------------+ |
| |
| |
+-----------------------------------------+
```
Since all these components build upon each other losing or damaging just one of them will render the disk undecryptable, it's threfore of paramount importance to backup the LUKS header and ideally set an backup password
or utilise more than one FIDO2 device. Each additional credential and password combination will require it's own LUKS keyslot since the credential secret is randomly generated for each new credential and will thus result
in a completly different secret.
## License
Licensed under
* Mozilla Public License 2.0, ([LICENSE-MPL](LICENSE-MPL) or https://www.mozilla.org/en-US/MPL/2.0/)
### Contribution
Unless you explicitly state otherwise, any contribution intentionally
submitted for inclusion in the work by you, as defined in the MPL 2.0
license, shall be licensed as above, without any additional terms or
conditions.
This is just the program itself, all intitrid scripts are mostly taylored to the latest 0.2.x version and will most likely not work with 0.3.0 due to breaking changes in the CLI interface.
I've decided it release the version in this state since I just do not have the time now or in the forseeable future to tewak all scripts since it's quite an tedious tasks which involves rebooting VMs countless times.
If you're interested to adapt or write scripts for an particular distro I'd be more than happy to accept pull requests.

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@@ -1,79 +0,0 @@
# fido2luks [![Crates.io Version](https://img.shields.io/crates/v/fido2luks.svg)](https://crates.io/crates/fido2luks)
This will allow you to unlock your LUKS encrypted disk with an FIDO2 compatible key.
Note: This has only been tested under Fedora 31, [Ubuntu 20.04](initramfs-tools/), [NixOS](https://nixos.org/nixos/manual/#sec-luks-file-systems-fido2) using a Solo Key, Trezor Model T
## Installation
### From Source
Installing from source requires the following dependencies:
Ubuntu: `cargo, libclang-dev, libcryptsetup-dev >= 2.2`
Fedora: `cargo, clang-devel, cryptsetup-devel`
To compile the fido2luks binary you can simply run `sudo cargo install --root /usr fido2luks` but since you may want to install the scripts included it this repo as well,
it's recommended to clone the repo and install from there.
``
git clone https://github.com/shimunn/fido2luks.git
cargo install --root /usr --path fido2luks
``
Continue with further instructions for [Ubuntu](initramfs-tools) or [Fedora](dracut)
### From Package
Ubuntu: see [releases](https://github.com/shimunn/fido2luks/releases)
NixOS: https://nixos.org/nixos/manual/#sec-luks-file-systems-fido2
ArchLinux:
* [AUR](https://aur.archlinux.org/packages/fido2luks/)
* [Git](PKGBUILD)
Fedora: coming soon
## Credentials
Depending on the version of cryptsetup and the age of your installation your LUKS header might be in the LUKS2 format already if that's the case fido2luks will be able to spare you from dealing with just another config file by simply storeing all the required information within your LUKS header.
If your header is still using the LUKS1 format you may convert it:
```
cryptsetup convert --type luks2 <device>
```
if you want to keep using LUKS1 due to other software such as pam_mount not being compatible with LUKS2 at the moment, you will have to generate credentials by hand an add them to `/etc/fido2luks.conf` otherwise you can skip this step.
```
fido2luks credential [optional name]
```
the generated hexadecimal credential can then be added to `FIDO2LUKS_CREDENTIAL_ID=` in `/etc/fido2luks.conf` multiple credentials can be separated by comma.
## Adding a Key
If you had to generate a credential in the previous step you'll have to provide it to the following commands as a parameter or via an environment variable:
```
set -a
. /etc/fido2luks.conf
```
To then add the key you need to have your current password/keyfile ready:
without having generated a credential in the previous step: `fido2luks -i add-key --gen-cred <device>`
with a keyfile: `fido2luks -i add-key --keyfile <path-to-keyfile <device>`
if you've confirmed at a later stage that everything works as expected you may want to remove your keyfile/password by running the previous commands with the `--exclusive` flag which will remove all other keys from the device.
## Replacing a Key
with password: `fido2luks -i replace-key <device>`
with keyfile: `fido2luks -i replace-key -d <path-to-keyfile> <device>`
with another fido2 derived key: `fido2luks -i replace-key -f <device>`

35
flake.lock generated
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@@ -1,21 +1,5 @@
{ {
"nodes": { "nodes": {
"cargo-deb": {
"flake": false,
"locked": {
"lastModified": 1627137192,
"narHash": "sha256-zDAwiETJquiViEvBKMuI9WWgSGhVDscL/m1ufKJENBw=",
"owner": "mmstick",
"repo": "cargo-deb",
"rev": "f603d105b4641e00640e46b189c6ee0c8f084de2",
"type": "github"
},
"original": {
"owner": "mmstick",
"repo": "cargo-deb",
"type": "github"
}
},
"naersk": { "naersk": {
"inputs": { "inputs": {
"nixpkgs": [ "nixpkgs": [
@@ -23,11 +7,11 @@
] ]
}, },
"locked": { "locked": {
"lastModified": 1623927034, "lastModified": 1639051343,
"narHash": "sha256-sGxlmfp5eXL5sAMNqHSb04Zq6gPl+JeltIZ226OYN0w=", "narHash": "sha256-62qARP+5Q0GmudcpuQHJP3/yXIgmUVoHR4orD/+FAC4=",
"owner": "nmattia", "owner": "nmattia",
"repo": "naersk", "repo": "naersk",
"rev": "e09c320446c5c2516d430803f7b19f5833781337", "rev": "ebde51ec0eec82dc71eaca03bc24cf8eb44a3d74",
"type": "github" "type": "github"
}, },
"original": { "original": {
@@ -38,11 +22,11 @@
}, },
"nixpkgs": { "nixpkgs": {
"locked": { "locked": {
"lastModified": 1627245147, "lastModified": 1638109994,
"narHash": "sha256-CQzH/4Mbhcx1HD+dtD7pZ0dHUZvX4eKN9b8Ifzz4gC4=", "narHash": "sha256-OpA37PTiPMIqoRJbufbl5rOLII7HeeGcA0yl7FoyCIE=",
"owner": "NixOS", "owner": "NixOS",
"repo": "nixpkgs", "repo": "nixpkgs",
"rev": "23098f20376cd1c874af476e5d8ef9169105b020", "rev": "a284564b7f75ac4db73607db02076e8da9d42c9d",
"type": "github" "type": "github"
}, },
"original": { "original": {
@@ -52,7 +36,6 @@
}, },
"root": { "root": {
"inputs": { "inputs": {
"cargo-deb": "cargo-deb",
"naersk": "naersk", "naersk": "naersk",
"nixpkgs": "nixpkgs", "nixpkgs": "nixpkgs",
"utils": "utils" "utils": "utils"
@@ -60,11 +43,11 @@
}, },
"utils": { "utils": {
"locked": { "locked": {
"lastModified": 1623875721, "lastModified": 1638122382,
"narHash": "sha256-A8BU7bjS5GirpAUv4QA+QnJ4CceLHkcXdRp4xITDB0s=", "narHash": "sha256-sQzZzAbvKEqN9s0bzWuYmRaA03v40gaJ4+iL1LXjaeI=",
"owner": "numtide", "owner": "numtide",
"repo": "flake-utils", "repo": "flake-utils",
"rev": "f7e004a55b120c02ecb6219596820fcd32ca8772", "rev": "74f7e4319258e287b0f9cb95426c9853b282730b",
"type": "github" "type": "github"
}, },
"original": { "original": {

View File

@@ -3,17 +3,13 @@
inputs = { inputs = {
utils.url = "github:numtide/flake-utils"; utils.url = "github:numtide/flake-utils";
cargo-deb = {
flake = false;
url = "github:mmstick/cargo-deb";
};
naersk = { naersk = {
url = "github:nmattia/naersk"; url = "github:nmattia/naersk";
inputs.nixpkgs.follows = "nixpkgs"; inputs.nixpkgs.follows = "nixpkgs";
}; };
}; };
outputs = { self, nixpkgs, utils, naersk, cargo-deb }: outputs = { self, nixpkgs, utils, naersk }:
let let
root = ./.; root = ./.;
pname = (builtins.fromTOML (builtins.readFile ./Cargo.toml)).package.name; pname = (builtins.fromTOML (builtins.readFile ./Cargo.toml)).package.name;
@@ -32,45 +28,6 @@
packages.${pname} = naersk-lib.buildPackage { packages.${pname} = naersk-lib.buildPackage {
inherit pname root buildInputs nativeBuildInputs LIBCLANG_PATH; inherit pname root buildInputs nativeBuildInputs LIBCLANG_PATH;
}; };
packages."${pname}-deb" =
let
cargoDeb = naersk-lib.buildPackage {
pname = "cargo-deb";
root = cargo-deb;
};
pkg = packages.${pname};
vm = pkgs.vmTools.diskImageFuns.ubuntu1804x86_64 { extraPackages = [ "cargo" "cryptsetup" "libclang-dev" "libcryptsetup-dev" ]; };
makefile = pkgs.writeText "Makefile" "
.PHONY: install
cargo-deb:
cargo install --debug --path cargo-deb
install: cargo-deb
cargo-deb
mkdir -p debs
cp target/debian/*.deb debs/
";
src = pkgs.runCommandLocal "${pname}-vendored" {} ''
mkdir -p $out/.cargo $out/cargo-deb/.cargo
printf '${pkg.cargoconfig}' > $out/.cargo/config.toml;
printf '${cargoDeb.cargoconfig}' > $out/cargo-deb/.cargo/config.toml;
printf '.PHONY: install\ninstall:\n\tcargo install --debug --path cargo-deb\n\tcargo-deb\n\tmkdir -p debs\n\tcp target/debian/*.deb debs/' > $out/Makefile
cp -r ${pkg.src}/. $out/
cp -r ${cargoDeb.src}/. $out/cargo-deb/
'';
args = {
diskImage = vm;
inherit src;
name = pname;
buildInputs = [ ];
meta.description = "No descr";
};
in
pkgs.releaseTools.debBuild args;
defaultPackage = packages.${pname}; defaultPackage = packages.${pname};
# `nix run` # `nix run`

View File

@@ -433,6 +433,8 @@ pub fn run_cli() -> Fido2LuksResult<()> {
credentials, credentials,
retries, retries,
dry_run, dry_run,
allow_discards,
..
} => { } => {
let inputs = |q: &str, verify: bool| -> Fido2LuksResult<(Option<String>, [u8; 32])> { let inputs = |q: &str, verify: bool| -> Fido2LuksResult<(Option<String>, [u8; 32])> {
get_input(&secret, &authenticator, args.interactive, q, verify) get_input(&secret, &authenticator, args.interactive, q, verify)
@@ -469,7 +471,7 @@ pub fn run_cli() -> Fido2LuksResult<()> {
}); });
secret(Cow::Borrowed(&credentials.0)).and_then(|(secret, cred)| { secret(Cow::Borrowed(&credentials.0)).and_then(|(secret, cred)| {
log(&|| format!("credential used: {}", hex::encode(&cred.id))); log(&|| format!("credential used: {}", hex::encode(&cred.id)));
luks_dev.activate(&name, &secret, luks.slot, *dry_run) luks_dev.activate(&name, &secret, luks.slot, *dry_run, *allow_discards)
}) })
} else if luks2 && !luks.disable_token { } else if luks2 && !luks.disable_token {
luks_dev.activate_token( luks_dev.activate_token(
@@ -487,6 +489,7 @@ pub fn run_cli() -> Fido2LuksResult<()> {
}), }),
luks.slot, luks.slot,
*dry_run, *dry_run,
*allow_discards,
) )
} else if luks_dev.is_luks2()? && luks.disable_token { } else if luks_dev.is_luks2()? && luks.disable_token {
// disable-token is mostly cosmetic in this instance // disable-token is mostly cosmetic in this instance
@@ -499,7 +502,11 @@ pub fn run_cli() -> Fido2LuksResult<()> {
match e { match e {
Fido2LuksError::WrongSecret if retries > 0 => {} Fido2LuksError::WrongSecret if retries > 0 => {}
Fido2LuksError::AuthenticatorError { ref cause } Fido2LuksError::AuthenticatorError { ref cause }
if cause.kind() == FidoErrorKind::Timeout && retries > 0 => {} if match cause.kind() {
FidoErrorKind::Timeout => true,
FidoErrorKind::CborError(e) if e.code() == 0x33 => true,
_ => false,
} && retries > 0 => {}
e => return Err(e), e => return Err(e),
}; };

View File

@@ -244,6 +244,9 @@ pub enum Command {
/// Perform the whole procedure without mounting the LUKS volume on success /// Perform the whole procedure without mounting the LUKS volume on success
#[structopt(long = "dry-run")] #[structopt(long = "dry-run")]
dry_run: bool, dry_run: bool,
/// Pass SSD trim instructions to the underlying block device
#[structopt(long = "allow-discards", env = "FIDO2LUKS_ALLOW_DISCARDS")]
allow_discards: bool,
}, },
/// Generate a new FIDO credential /// Generate a new FIDO credential
#[structopt(name = "credential")] #[structopt(name = "credential")]

View File

@@ -1,8 +1,8 @@
use crate::error::*; use crate::error::*;
use libcryptsetup_rs::{ use libcryptsetup_rs::{
CryptActivateFlags, CryptDevice, CryptInit, CryptTokenInfo, EncryptionFormat, KeyslotInfo, CryptActivateFlag, CryptActivateFlags, CryptDevice, CryptInit, CryptTokenInfo,
TokenInput, EncryptionFormat, KeyslotInfo, TokenInput,
}; };
use std::collections::{HashMap, HashSet}; use std::collections::{HashMap, HashSet};
use std::path::Path; use std::path::Path;
@@ -238,15 +238,15 @@ impl LuksDevice {
secret: &[u8], secret: &[u8],
slot_hint: Option<u32>, slot_hint: Option<u32>,
dry_run: bool, dry_run: bool,
allow_discard: bool,
) -> Fido2LuksResult<u32> { ) -> Fido2LuksResult<u32> {
let mut flags = CryptActivateFlags::empty();
if allow_discard {
flags = CryptActivateFlags::new(vec![CryptActivateFlag::AllowDiscards]);
}
self.device self.device
.activate_handle() .activate_handle()
.activate_by_passphrase( .activate_by_passphrase(Some(name).filter(|_| !dry_run), slot_hint, secret, flags)
Some(name).filter(|_| !dry_run),
slot_hint,
secret,
CryptActivateFlags::empty(),
)
.map_err(LuksError::activate) .map_err(LuksError::activate)
} }
@@ -256,6 +256,7 @@ impl LuksDevice {
secret: impl Fn(Vec<String>) -> Fido2LuksResult<([u8; 32], String)>, secret: impl Fn(Vec<String>) -> Fido2LuksResult<([u8; 32], String)>,
slot_hint: Option<u32>, slot_hint: Option<u32>,
dry_run: bool, dry_run: bool,
allow_discard: bool,
) -> Fido2LuksResult<u32> { ) -> Fido2LuksResult<u32> {
if !self.is_luks2()? { if !self.is_luks2()? {
return Err(LuksError::Luks2Required.into()); return Err(LuksError::Luks2Required.into());
@@ -299,7 +300,7 @@ impl LuksDevice {
.chain(std::iter::once(None).take(slots.is_empty() as usize)), // Try all slots as last resort .chain(std::iter::once(None).take(slots.is_empty() as usize)), // Try all slots as last resort
); );
for slot in slots { for slot in slots {
match self.activate(name, &secret, slot, dry_run) { match self.activate(name, &secret, slot, dry_run, allow_discard) {
Err(Fido2LuksError::WrongSecret) => (), Err(Fido2LuksError::WrongSecret) => (),
res => return res, res => return res,
} }