/hsmwiz

HSMWiz is a frontend for OpenSC, pkcs11tool and pkcs15tool to ease handling of HSM smartcards

Primary LanguagePythonGNU General Public License v3.0GPL-3.0

hsmwiz

HSMWiz is a frontend for OpenSC to ease handling of HSMs like the NitroKey HSM USB smart card. It was previously called "nitrotool" since it only targeted the NitroKey, but has since been renamed because it actually is not using anything specific to the NitroKey.

Basically, it is just boilerplate that does nothing more than what is already described in the excellent OpenSC tutorial for the Smart Card HSM. However, there's some annoying issues with that -- multiple tools are needed (pkcs11-tool, pkcs15-tool, sc-hsm-tool, OpenSSL) and output formats are sometimes not very user friendly (e.g., public keys are exported as binary DER blobs instead of PEM files). So I wrote this little frontend to encapsulate common tasks a bit.

Hardware

The hardware I'm working with is the NitroKey HSM, which is a quite affordable smart-card based USB HSM. I'm in no way affiliated with them whatsoever, just think they have a pretty cool product.

CA management and PKI

Once you've a good grip on keys that are working on your HSM, you might want to use it to create a CA and issue certificates signed by that CA (which has its key on a hardware token such as the NitroKey HSM). Lucky you, check out the x509sak (X.509 Swiss Army Knife), the sibling project of hsmwiz, which has that exact capability.

Usage

All commands have comprehensive help pages. You can get a summary of available commands by typing:

$ hsmwiz
Syntax: hsmwiz [command] [options]

Available commands:

Options vary from command to command. To receive further info, type
    hsmwiz [command] --help
    identify           Check if a HSM is connected and list all contents
    verifypin          Try to login a HSM by entering a PIN or SO-PIN
    checkengine        Check if the OpenSSL engine driver works
    init               Initialize the smartcard for the first time, set default
                       SO-PIN and PIN
    format             Reinitialize the smartcard completely (removing all keys
                       and certificates) and set SO-PIN and PIN back to their
                       factory default
    changepin          Change device PIN or SO-PIN
    explore            Explore the smartcard structure interactively
    unblock            Unblock the transponder's blocked PIN using the SO-PIN
    keygen             Create a new private keypair on the smartcard
    getkey             Fetch a public key from the smartcard
    removekey          Remove a keypair from the smartcard
    gencsr             Generate a certificate signing request from a HSM-
                       contained private key
    gencrt             Generate a self-signed certificate from a HSM-contained
                       private key
    putcrt             Put a certificate on the smartcard

Then, you can lookup individual help pages:

$ hsmwiz keygen --help
usage: hsmwiz keygen [--id key_id] [--label key_label] [--pin pin]
                          [--so-path path] [-v] [--help]
                          keyspec

Create a new private keypair on the smartcard

positional arguments:
  keyspec            Key specification string to generate. Can be either
                     'rsa:BITLENGTH' or 'EC:CURVENAME'. Examples are
                     'rsa:1024', 'EC:brainpool256r1' or 'EC:prime256v1'.

optional arguments:
  --id key_id        Specifies the key ID to use for generating the new key.
                     Must be an integer and defaults to 1.
  --label key_label  Specifies the key label to use for generating the new
                     key.
  --pin pin          Specifies the PIN of the smartcard. If this argument is
                     not given, the command will ask for it interactively.
  --so-path path     Search path, separated by ':' characters, in which to
                     look for shared objects like opensc-pkcs11.so. Defaults
                     to /usr/local/lib:/usr/lib:/usr/lib/x86_64-linux-gnu
  -v, --verbose      Increase verbosity. Can be specified multiple times.
  --help             Show this help page.

Example: General Stuff

You can first query a transponder:

$ hsmwiz identify
Using reader with a card: Nitrokey Nitrokey HSM (010000000000000000000000) 00 00
Version              : 2.6
Config options       :
  User PIN reset with SO-PIN enabled
SO-PIN tries left    : 15
User PIN tries left  : 3

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Default SO-PIN: 3537363231383830    Default PIN: 648219
pkcs15-tool --dump
Using reader with a card: Nitrokey Nitrokey HSM (010000000000000000000000) 00 00
PKCS#15 Card [SmartCard-HSM]:
	Version        : 0
	Serial number  : DENK#######
	Manufacturer ID: www.CardContact.de
	Flags          :
PIN [UserPIN]
	Object Flags   : [0x3], private, modifiable
	Auth ID        : 02
	ID             : 01
	Flags          : [0x812], local, initialized, exchangeRefData
	Length         : min_len:6, max_len:15, stored_len:0
	Pad char       : 0x00
	Reference      : 129 (0x81)
	Type           : ascii-numeric
	Path           : e82b0601040181c31f0201::
	Tries left     : 3

PIN [SOPIN]
	Object Flags   : [0x1], private
	ID             : 02
	Flags          : [0x9A], local, unblock-disabled, initialized, soPin
	Length         : min_len:16, max_len:16, stored_len:0
	Pad char       : 0x00
	Reference      : 136 (0x88)
	Type           : bcd
	Path           : e82b0601040181c31f0201::
	Tries left     : 15

Then, you could use it to generate a new private key:

$ hsmwiz genkey EC:prime256v1 --label fookey
Using slot 0 with a present token (0x0)
Logging in to "UserPIN (SmartCard-HSM)".
Please enter User PIN:
Key pair generated:
Private Key Object; EC
  label:      fookey
  ID:         01
  Usage:      sign, derive
Public Key Object; EC  EC_POINT 256 bits
  EC_POINT:   04410416d236f109229332666236b7af0d46d547cbb125151e1a6a657f2b2b8495b9207d40836ae3f276b55a8989385f46f16006677939b580b66636086dc3f095a4e2
  EC_PARAMS:  06082a8648ce3d030107
  label:      fookey
  ID:         01
  Usage:      verify, derive

Check if that worked by identifying again:

$ hsmwiz id
[...]
Private EC Key [fookey]
	Object Flags   : [0x3], private, modifiable
	Usage          : [0x10C], sign, signRecover, derive
	Access Flags   : [0x1D], sensitive, alwaysSensitive, neverExtract, local
	FieldLength    : 256
	Key ref        : 1 (0x1)
	Native         : yes
	Auth ID        : 01
	ID             : 01
	MD:guid        : 7a767d92-49ec-5894-ddf2-ca7dc72ee476

Public EC Key [fookey]
	Object Flags   : [0x0]
	Usage          : [0x40], verify
	Access Flags   : [0x2], extract
	FieldLength    : 256
	Key ref        : 0 (0x0)
	Native         : no
	ID             : 01
	DirectValue    : <present>

Grab the public key:

$ hsmwiz getpubkey --label fookey
Using slot 0 with a present token (0x0)
Logging in to "UserPIN (SmartCard-HSM)".
Please enter User PIN:
# ECC key:
-----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEFtI28QkikzJmYja3rw1G1UfLsSUV
HhpqZX8rK4SVuSB9QINq4/J2tVqJiThfRvFgBmd5ObWAtmY2CG3D8JWk4g==
-----END PUBLIC KEY-----

Or create a CSR from a HSM key:

$ hsmwiz gencsr --pin 648219
engine "pkcs11" set.
-----BEGIN CERTIFICATE REQUEST-----
MIHVMH0CAQAwGzEZMBcGA1UEAwwQTml0cm9LZXkgRXhhbXBsZTBZMBMGByqGSM49
AgEGCCqGSM49AwEHA0IABBbSNvEJIpMyZmI2t68NRtVHy7ElFR4aamV/KyuElbkg
fUCDauPydrVaiYk4X0bxYAZneTm1gLZmNghtw/CVpOKgADAKBggqhkjOPQQDAgNI
ADBFAiBybom3wRlgBDmNsm34rcOol62sgi0BHbz2PqJvwBshpgIhALdHw+PkEFeJ
pQD+3QcftVe9CZJu0uW25MEcg3S/yKOG
-----END CERTIFICATE REQUEST-----

Example: Setting up a NitroKey HSM for SSH authentication

Generate a key. For OpenSSH before v8.0, this has to be an RSA key. You can create an ECDSA/secp256r1 key by using:

$ hsmwiz genkey --id 2 --label my-ec-ssh-key --pin 648219 EC:prime256v1
Using slot 0 with a present token (0x0)
Key pair generated:
Private Key Object; EC
  label:      sshkey
  ID:         02
  Usage:      sign, derive
Public Key Object; EC  EC_POINT 256 bits
  EC_POINT:   044104ae19243bc5847e589392ffd6e4a463fd64826db96664b7d61a26c22eb523808bb4e8a31018be80f7aa1353c1f082a1a0c52ae4678129aad91f7908e62ad3081d
  EC_PARAMS:  06082a8648ce3d030107
  label:      sshkey
  ID:         02
  Usage:      verify, derive

Alternatively (e.g., if your OpenSSH version doesn't permit ECDSA/PKCS#11), create an RSA keypair inside the HSM:

$ hsmwiz genkey --id 1 --label my-ssh-key --pin 648219 rsa:2048
Using slot 0 with a present token (0x0)
Key pair generated:
Private Key Object; RSA
  label:      my-ssh-key
  ID:         01
  Usage:      decrypt, sign, unwrap
Public Key Object; RSA 2048 bits
  label:      my-ssh-key
  ID:         01
  Usage:      encrypt, verify, wrap

After you have created a key, you can easily extract the public key you just created from the NitroKey in SSH format. For the ECC case, this is done by:

$ hsmwiz getkey --id 2 --key-format ssh --pin 648219
Using slot 0 with a present token (0x0)
ecdsa-sha2-nistp256 AAAAE2VjZHNhLXNoYTItbmlzdHAyNTYAAAAIbmlzdHAyNTYAAABBBK4ZJDvFhH5Yk5L/1uSkY/1kgm25ZmS31homwi61I4CLtOijEBi+gPeqE1PB8IKhoMUq5GeBKarZH3kI5irTCB0=

Or in the case of the RSA example:

$ hsmwiz getkey --id 1 --key-format ssh --pin 648219
Using slot 0 with a present token (0x0)
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCV6Fqr80gKq+wV+MA0dMltHTuwMwyVLBvLPdtVYdsw4S2YAjfTDnLATFHOhId/fFDMbSv9qH3YI/F8ryXM8MY53J1bd3Vd5iPbnG8/Azk0F5IUw9u/bhL6/39nFWJqSKww68pe4BFtCHMfPLchT9A6lMk0QOe8rU8VNkgcZsMfQ+iDzd5OmEC7JdlJSY7kCSPHkF/SoJLk5BuftV3kVCm2VAhkMgObbNnw3xHoiL0yv/JZyBly+ssDog72EkNvbYL9bvVMk2ZqYhLESPTwMnh7x1DyznlIC2R3XuqKkrQ5ztMblCAli5S7s1yYSKj4jCYzyIZf2nfPoCTTiqNs7Eyd

Add the public key line to the ~/.ssh/authorized_keys file on the user/host you want to authenticate with (i.e., the one with the OpenSSH server).

When you want to login to that server using the HSM, do:

$ ssh -o "PKCS11Provider opensc-pkcs11.so" joe@reliant
Enter PIN for 'UserPIN (SmartCard-HSM)':
Welcome to Ubuntu 17.10 (GNU/Linux 4.13.0 x86_64)
Last login: Sat Apr  7 18:40:52 2018 from 127.0.0.1
reliant joe [~]:

You'll notice that you were asked to enter your NitroKey PIN. After entry, it allows SSH access!

Dependencies

hsmwiz itself only depends on Python3, but assumes you've installed PC/SC, OpenSC and OpenSSL. It'll use those tools on the command line.

License

GNU GPL-3.