boot.initrd.luks: Adding FIDO2 support

This commit is contained in:
Marek Mahut 2020-01-13 12:07:48 +01:00
parent 48f07787ab
commit dea2fe9f39

View File

@ -103,6 +103,33 @@ let
fi
return 0
}
wait_fido2key () {
local secs="''${1:-10}"
fido2luks connected 1>/dev/null 2>&1
if [ $? != 0 ]; then
echo -n "Waiting $secs seconds for the FIDO2 key to appear..."
local success=false
for try in $(seq $secs); do
echo -n .
sleep 1
fido2luks connected 1>/dev/null 2>&1
if [ $? == 0 ]; then
success=true
break
fi
done
if [ $success == true ]; then
echo " - success";
return 0
else
echo " - failure";
return 1
fi
fi
return 0
}
'';
preCommands = ''
@ -139,7 +166,7 @@ let
umount /crypt-ramfs 2>/dev/null
'';
openCommand = name': { name, device, header, keyFile, keyFileSize, keyFileOffset, allowDiscards, yubikey, gpgCard, fallbackToPassword, ... }: assert name' == name;
openCommand = name': { name, device, header, keyFile, keyFileSize, keyFileOffset, allowDiscards, yubikey, gpgCard, fido2, fallbackToPassword, ... }: assert name' == name;
let
csopen = "cryptsetup luksOpen ${device} ${name} ${optionalString allowDiscards "--allow-discards"} ${optionalString (header != null) "--header=${header}"}";
cschange = "cryptsetup luksChangeKey ${device} ${optionalString (header != null) "--header=${header}"}";
@ -387,7 +414,29 @@ let
}
''}
${if (luks.yubikeySupport && (yubikey != null)) || (luks.gpgSupport && (gpgCard != null)) then ''
${optionalString (luks.fido2Support && (fido2.credential != null)) ''
open_with_hardware() {
local passsphrase
if wait_fido2key ${toString fido2.gracePeriod}; then
${if fido2.passwordLess then ''
export passphrase=""
'' else ''
echo -n "FIDO2 salt for ${device}: "
read -rs passphrase
echo
''}
echo "Waiting for your FIDO2 device..."
fido2luks -i open ${device} ${name} ${fido2.credential} --salt string:$passphrase
else
echo "No FIDO2 key found, falling back to normal open procedure"
open_normally
fi
}
''}
${if (luks.yubikeySupport && (yubikey != null)) || (luks.gpgSupport && (gpgCard != null)) || (luks.fido2Support && (fido2.credential != null)) then ''
open_with_hardware
'' else ''
open_normally
@ -608,6 +657,31 @@ in
});
};
fido2 = {
credential = mkOption {
default = null;
example = "f1d00200d8dc783f7fb1e10ace8da27f8312d72692abfca2f7e4960a73f48e82e1f7571f6ebfcee9fb434f9886ccc8fcc52a6614d8d2";
type = types.str;
description = "The FIDO2 credential ID.";
};
gracePeriod = mkOption {
default = 10;
type = types.int;
description = "Time in seconds to wait for the FIDO2 key.";
};
passwordLess = mkOption {
default = false;
type = types.bool;
description = ''
Defines whatever to use an empty string as a default salt.
Enable only when your device is PIN protected, such as <link xlink:href="https://trezor.io/">Trezor</link>.
'';
};
};
yubikey = mkOption {
default = null;
description = ''
@ -706,6 +780,15 @@ in
and a Yubikey to work with this feature.
'';
};
boot.initrd.luks.fido2Support = mkOption {
default = false;
type = types.bool;
description = ''
Enables support for authenticating with FIDO2 devices.
'';
};
};
config = mkIf (luks.devices != {} || luks.forceLuksSupportInInitrd) {
@ -714,6 +797,14 @@ in
[ { assertion = !(luks.gpgSupport && luks.yubikeySupport);
message = "Yubikey and GPG Card may not be used at the same time.";
}
{ assertion = !(luks.gpgSupport && luks.fido2Support);
message = "FIDO2 and GPG Card may not be used at the same time.";
}
{ assertion = !(luks.fido2Support && luks.yubikeySupport);
message = "FIDO2 and Yubikey may not be used at the same time.";
}
];
# actually, sbp2 driver is the one enabling the DMA attack, but this needs to be tested
@ -753,6 +844,11 @@ in
chmod +x $out/bin/openssl-wrap
''}
${optionalString luks.fido2Support ''
copy_bin_and_libs ${pkgs.fido2luks}/bin/fido2luks
''}
${optionalString luks.gpgSupport ''
copy_bin_and_libs ${pkgs.gnupg}/bin/gpg
copy_bin_and_libs ${pkgs.gnupg}/bin/gpg-agent
@ -783,6 +879,9 @@ in
$out/bin/gpg-agent --version
$out/bin/scdaemon --version
''}
${optionalString luks.fido2Support ''
$out/bin/fido2luks --version
''}
'';
boot.initrd.preFailCommands = postCommands;