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@ -13,14 +13,13 @@ If you have a comment or suggestion, please open an [issue](https://github.com/d
* [Entropy](#entropy)
- [Creating keys](#creating-keys)
- [Master key](#master-key)
- [Subkeys](#subkeys)
- [Sub-keys](#sub-keys)
* [Signing](#signing)
* [Encryption](#encryption)
* [Authentication](#authentication)
- [Verify keys](#verify-keys)
- [Export keys](#export-keys)
- [Backup keys](#backup-keys)
- [Configure YubiKey](#configure-yubikey)
- [Verify](#verify)
- [Export](#export)
- [Backup](#backup)
- [Configure Smartcard](#configure-smartcard)
* [Change PIN](#change-pin)
* [Set information](#set-information)
@ -31,10 +30,6 @@ If you have a comment or suggestion, please open an [issue](https://github.com/d
- [Verify card](#verify-card)
- [Cleanup](#cleanup)
- [Using keys](#using-keys)
- [Import public key](#import-public-key)
* [Trust master key](#trust-master-key)
- [Insert YubiKey](#insert-yubikey)
- [Verifying signature](#verifying-signature)
- [SSH](#ssh)
* [Create configuration](#create-configuration)
* [Replace agents](#replace-agents)
@ -64,7 +59,7 @@ You will also need several small storage devices for booting a live image, creat
# Verify YubiKey
To confirm your YubiKey is genuine, open a [browser with U2F support](https://support.yubico.com/support/solutions/articles/15000009591-how-to-confirm-your-yubico-device-is-genuine-with-u2f) to [https://www.yubico.com/genuine/](https://www.yubico.com/genuine/). Insert your Yubico device, and select Verify Device` to begin the process. Touch the YubiKey when prompted, and if asked, allow it to see the make and model of the device. If you see `Verification complete`, your device is authentic.
To confirm your YubiKey is genuine, open a [browser with U2F support](https://support.yubico.com/support/solutions/articles/15000009591-how-to-confirm-your-yubico-device-is-genuine-with-u2f) to [https://www.yubico.com/genuine/](https://www.yubico.com/genuine/). Insert your Yubico device, and select *Verify Device* to begin the process. Touch the YubiKey when prompted, and if asked, allow it to see the make and model of the device. If you see *Verification complete*, your device is authentic.
This website verifies the YubiKey's device attestation certificates signed by a set of Yubico CAs, and helps mitigate [supply chain attacks](https://media.defcon.org/DEF%20CON%2025/DEF%20CON%2025%20presentations/DEFCON-25-r00killah-and-securelyfitz-Secure-Tokin-and-Doobiekeys.pdf).
@ -298,9 +293,9 @@ Disable networking for the remainder of the setup.
# Master key
The first key to generate is the master key. It will be used for certification only: to issue subkeys that are used for encryption, signing and authentication.
The first key to generate is the master key. It will be used for certification only: to issue sub-keys that are used for encryption, signing and authentication.
**Important** The master key should be kept offline at all times and only accessed to revoke or issue new subkeys.
**Important** The master key should be kept offline at all times and only accessed to revoke or issue new sub-keys. Keys can also be generated on the YubiKey itself to ensure no other copies exist.
You'll be prompted to enter and verify a passphrase - keep it handy as you'll need it throughout. To generate a strong passphrase which could be written down in a hidden or secure place; or memorized:
@ -409,7 +404,7 @@ Export the key ID as a [variable](https://stackoverflow.com/questions/1158091/de
$ export KEYID=0xFF3E7D88647EBCDB
```
# Subkeys
# Sub-keys
Edit the master key to add sub-keys:
@ -612,7 +607,7 @@ ssb rsa4096/0x3F29127E79649A3D
gpg> save
```
# Verify keys
# Verify
List the generated secret keys and verify the output:
@ -640,7 +635,7 @@ The output will display any problems with your key in red text. If everything is
> hokey may warn (orange text) about cross certification for the authentication key. GPG's [Signing Subkey Cross-Certification](https://gnupg.org/faq/subkey-cross-certify.html) documentation has more detail on cross certification, and gpg v2.2.1 notes "subkey <keyid> does not sign and so does not need to be cross-certified". hokey may also indicate a problem (red text) with `Key expiration times: []` on the primary key (see [Note #3](#notes) about not setting an expiry for the primary key).
# Export keys
# Export
The master key and sub-keys will be encrypted with your passphrase when exported.
@ -660,7 +655,7 @@ $ gpg --armor --export-secret-keys $KEYID -o \path\to\dir\mastersub.gpg
$ gpg --armor --export-secret-subkeys $KEYID -o \path\to\dir\sub.gpg
```
# Backup keys
# Backup
Once GPG keys are moved to YubiKey, they cannot be moved again! Create an **encrypted** backup of the keyring and consider using a [paper copy](https://www.jabberwocky.com/software/paperkey/) of the keys as an additional backup.
@ -821,7 +816,7 @@ $ gpg --armor --export $KEYID | sudo tee /mnt/public/$KEYID.txt
[...]
```
**Windows**
Windows:
```console
$ gpg --armor --export $KEYID -o \path\to\dir\pubkey.gpg
@ -847,7 +842,7 @@ Attach a USB disk and determine its label:
```console
$ dmesg | grep sd.\ at
sd2 at scsibus5 targ 1 lun 0: <Samsung, Flash Drive DUO, 1100> SCSI4 0/direct removable serial.50010000000000000001
sd2 at scsibus5 targ 1 lun 0: <TS-RDF5, SD Transcend, TS37> SCSI4 0/direct removable serial.00000000000000000000
```
Print the existing partitions to make sure it's the right device:
@ -856,7 +851,7 @@ Print the existing partitions to make sure it's the right device:
$ doas disklabel -h sd2
```
Initialize the disk by creating an `a` partition with FS type `RAID`:
Initialize the disk by creating an `a` partition with FS type `RAID` and size of 10 Megabytes:
```console
$ doas fdisk -iy sd2
@ -864,21 +859,25 @@ Writing MBR at offset 0.
$ doas disklabel -E sd2
Label editor (enter '?' for help at any prompt)
> a a
sd2> a a
offset: [64]
size: [62653436]
size: [31101776] 10M
FS type: [4.2BSD] RAID
> w
> q
No label changes.
sd2*> w
sd2> q
No label changes
```
Encrypt with bioctl:
```console
$ doas bioctl -c C -l sd2a softraid0
New passphrase:
Re-type passphrase:
softraid0: CRYPTO volume attached as sd3
```
Create an `i` partition, then create and mount the filesystem:
Create an `i` partition on the new crypto volume and the filesystem:
```console
$ doas fdisk -iy sd3
@ -886,23 +885,22 @@ Writing MBR at offset 0.
$ doas disklabel -E sd3
Label editor (enter '?' for help at any prompt)
> a i
sd3> a i
offset: [64]
size: [62637371]
size: [16001]
FS type: [4.2BSD]
> w
> q
sd3*> w
sd3> q
No label changes.
$ doas newfs sd3i
/dev/rsd3i: 30584.6MB in 62637344 sectors of 512 bytes
152 cylinder groups of 202.47MB, 12958 blocks, 25984 inodes each
/dev/rsd3i: 7.8MB in 16000 sectors of 512 bytes
4 cylinder groups of 1.95MB, 125 blocks, 256 inodes each
super-block backups (for fsck -b #) at:
32, 414688, 829344, 1244000, 1658656, 2073312, 2487968, 2902624, 3317280, 3731936, 4146592, 4561248, 4975904,
[...]
32, 4032, 8032, 12032,
```
Mount the filesystem and copy the temporary GNUPG directory:
Mount the filesystem and copy the temporary directory with the keyring:
```console
$ doas mkdir /mnt/encrypted-usb
@ -914,7 +912,7 @@ $ doas cp -avi $GNUPGHOME /mnt/encrypted-usb
Keep the backup mounted if you plan on setting up two or more keys as `keytocard` **will [delete](https://lists.gnupg.org/pipermail/gnupg-users/2016-July/056353.html) the local copy** on save.
Otherwise, unmount and disconnected the encrypted USB disk:
Otherwise, unmount and disconnected the encrypted volume:
```console
$ doas umount /mnt/encrypted-usb
@ -924,26 +922,40 @@ $ doas bioctl -d sd3
See [OpenBSD FAQ#14](https://www.openbsd.org/faq/faq14.html#softraidCrypto) for more information.
# Configure YubiKey
Create another partition to store the public key, or skip this step if you plan on uploading it to a key server.
**Note** YubiKey NEO shipped after November 2015 have [all modes enabled](https://www.yubico.com/support/knowledge-base/categories/articles/yubikey-neo-manager/); so this step may be skipped. Older versions of the YubiKey NEO may need to be reconfigured as a composite USB device (HID + CCID) which allows OTPs to be emitted while in use as a SmartCard.
Plug in YubiKey and configure it with the `ykpersonalize` utility:
**Important** Without the public key, you will not be able to use GPG to encrypt, decrypt, nor sign messages. However, you will still be able to use YubiKey for SSH authentication.
```console
$ sudo ykpersonalize -m82
Firmware version 4.3.7 Touch level 527 Program sequence 1
$ doas disklabel -E sd2
Label editor (enter '?' for help at any prompt)
sd2> a b
offset: [32130]
size: [31069710] 10M
FS type: [swap] 4.2BSD
sd2*> w
sd2> q
No label changes.
The USB mode will be set to: 0x82
$ doas newfs sd2b
/dev/rsd2b: 15.7MB in 32096 sectors of 512 bytes
5 cylinder groups of 3.89MB, 249 blocks, 512 inodes each
super-block backups (for fsck -b #) at:
32, 8000, 15968, 23936, 31904,
Commit? (y/n) [n]: y
$ doas mkdir /mnt/public
$ doas mount /dev/sd2b /mnt/public
$ gpg --armor --export $KEYID | doas tee /mnt/public/$KEYID.txt
-----BEGIN PGP PUBLIC KEY BLOCK-----
[...]
```
The -m option is the mode command. To see the different modes, enter `ykpersonalize -help`. Mode 82 (in hex) enables the YubiKey NEO as a composite USB device (HID + CCID). Once you have changed the mode, you need to re-boot the YubiKey, so remove and re-insert it. On YubiKey NEO with firmware version 3.3 or higher, you can enable composite USB device with `-m86` instead of `-m82`.
# Configure Smartcard
**Windows** Use the [YubiKey NEO Manager](https://www.yubico.com/products/services-software/download/yubikey-neo-manager/) to enable CCID functionality.
# Configure Smartcard
Use GPG to configure YubiKey as a smartcard:
```console
@ -1196,14 +1208,6 @@ $ gpg --delete-secret-key $KEYID
# Using keys
You can reboot back into the Live image to test YubiKey.
Install required programs:
```console
$ sudo apt-get update && sudo apt-get install -y \
gnupg2 gnupg-agent scdaemon pcscd
```
Download [drduh/config/gpg.conf](https://github.com/drduh/config/blob/master/gpg.conf):
@ -1213,20 +1217,34 @@ $ cd ~/.gnupg ; wget https://raw.githubusercontent.com/drduh/config/master/gpg.c
$ chmod 600 gpg.conf
```
# Import public key
Install the required packages and mount the non-encrypted volume created earlier:
To import the public key from the non-encrypted volume created earlier:
**Linux**
```console
$ sudo mount /dev/sdb2 /mnt
$ sudo apt-get update && sudo apt-get install -y \
gnupg2 gnupg-agent gnupg-curl scdaemon pcscd
$ sudo mount /dev/sdb2 /mnt
```
**OpenBSD**
```console
$ doas pkg_add gnupg pcsc-tools
$ doas mount /dev/sd2b /mnt
```
Import the key:
```console
$ gpg --import /mnt/pubkey.txt
gpg: key 0xFF3E7D88647EBCDB: public key "Dr Duh <doc@duh.to>" imported
gpg: Total number processed: 1
gpg: imported: 1
```
To download the public key from a keyserver:
Or download the public key from a keyserver:
```console
$ gpg --recv $KEYID
@ -1237,14 +1255,6 @@ gpg: Total number processed: 1
gpg: imported: 1
```
If you get the error `gpgkeys: HTTP fetch error 1: unsupported protocol` - this means you need to install a special version of curl which supports GPG:
```console
$ sudo apt-get install -y gnupg-curl
```
## Trust master key
Edit the master key to assign it ultimate trust by selecting `trust` then option `5`:
```console
@ -1283,8 +1293,6 @@ sub 4096R/0x3F29127E79649A3D created: 2017-10-09 expires: 2018-10-09 usage:
gpg> quit
```
# Insert YubiKey
Remove and re-insert the YubiKey and check the status:
```console