SoftHSMv2
First, we install SoftHSMv2 and configure it to store tokens in the default location /var/lib/softhsm/tokens
. We also need to give the softhsm
group permission to this directory as this is how the keyless
user will access this directory.
sudo apt-get install -y softhsm2 opensc
#...
cat <<EOF | sudo tee /etc/softhsm/softhsm2.confdirectories.tokendir = /var/lib/softhsm/tokensobjectstore.backend = filelog.level = DEBUGslots.removable = falseEOF
sudo mkdir /var/lib/softhsm/tokenssudo chown root:softhsm $_sudo chmod 0770 /var/lib/softhsm/tokenssudo usermod -G softhsm keylesssudo usermod -G softhsm $(whoami)
echo 'export SOFTHSM2_CONF=/etc/softhsm/softhsm2.conf' | tee -a ~/.profilesource ~/.profile
Next, we create a token in slot 0 called test-token
and secure it with a PIN of 1234
. In this slot we’ll store the RSA keys for our SSL certificates for keyless-softhsm.example.com
.
sudo -u keyless softhsm2-util --init-token --slot 0 --label test-token --pin 1234 --so-pin 4321
The token has been initialized.
Using cfssl, we generate the private keys and Certificate Signing Requests (CSRs), the latter of which will be sent to a Certificate Authority (CA) for signing.
cat <<EOF | tee csr.json{ "hosts": [ "keyless-softhsm.example.com" ], "CN": "keyless-softhsm.example.com", "key": { "algo": "rsa", "size": 2048 }, "names": [{ "C": "US", "L": "San Francisco", "O": "TLS Fun", "OU": "Technical Operations", "ST": "California" }]}EOF
cfssl genkey csr.json | cfssljson -bare certificate
2018/08/12 00:52:22 [INFO] generate received request2018/08/12 00:52:22 [INFO] received CSR2018/08/12 00:52:22 [INFO] generating key: rsa-20482018/08/12 00:52:22 [INFO] encoded CSR
Now that the key has been generated, it’s time to load it into the slot we created. Before doing so, we need to convert from PKCS#1 to PKCS#8 format. During import, we specify the token and PIN from token initialization and provide a unique hexadecimal ID and label to the key.
openssl pkcs8 -topk8 -inform PEM -outform PEM -nocrypt -in certificate-key.pem -out certificate-key.p8sudo chown keyless certificate-key.p8
sudo -u keyless softhsm2-util --pin 1234 --import ./certificate-key.p8 --token test-token --id a000 --label rsa-privkey
Found slot 915669571 with matching token label.The key pair has been imported.
After importing we ask pkcs11-tool
to confirm the objects have been successfully stored in the token.
sudo -u keyless pkcs11-tool --module /usr/lib/softhsm/libsofthsm2.so -l -p 1234 --token test-token --list-objects
Public Key Object; RSA 2048 bits label: rsa-privkey ID: a000 Usage: verifyPrivate Key Object; RSA label: rsa-privkey ID: a000 Usage: sign
With the keys in place, it’s time to build the configuration file that the key server will read on startup. The id
refers to the hexadecimal ID you provided to the softhsm2-util
import statement; we used a000
so it is encoded as %a0%00
. The module-path
will vary slightly based on the Linux distribution you are using. On Debian it should be /usr/lib/softhsm/libsofthsm2.so
.
Open up /etc/keyless/gokeyless.yaml
and immediately after
private_key_stores: - dir: /etc/keyless/keys
add
- uri: pkcs11:token=test-token;id=%a0%00?module-path=/usr/lib/softhsm/libsofthsm2.so&pin-value=1234&max-sessions=1
Save the config file, restart gokeyless
, and verify it started successfully.
sudo systemctl restart gokeyless.servicesudo systemctl status gokeyless.service -l