Using an Aladdin eToken PRO to generate grid proxies

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Once your grid certificate and private key are safely stored on your eToken, you can generate grid proxies directly from the eToken.

A shell script ( mkproxy script ) was written for this purpose. This script requires quite a few special programs and libraries, which need to be installed before attempting to use the mkproxy script.

Downloading the required files

If you have installed the etoken-mkproxy RPM then all required files are already installed.

Alternatively, for manual installations, you can download and install the appropriate tarball for your platform:

All required program files and libraries for running the mkproxy script are distributed in this tarball. This tarball also includes the mkproxy script itself so there is no need to download it separately.

Please read the instructions on Using an Aladdin eToken PRO to store grid certificates to install the eToken RTE software before attempting to use this script.

The mkproxy script has been tested on

  • Windows XP (using cygwin)
  • Linux Fedora Core 5 (fc5)
  • Linux CentOS 4, Scientific Linux 4 (rhel4)
  • Linux openSuse 10 (suse10)

In the near future we hope to test it on MacOS X as well.

Note On Windows, the Cygwin toolkit ( http://www.cygwin.com/ ) needs to be installed before attempting to use the mkproxy script. It does NOT work on Windows using either a command shell or the MingW/MSys shell.

mkproxy script usage

If you have installed a single grid certificate on your eToken you can now generate a grid proxy using the command 

 ./mkproxy

Which will return 

 Starting Aladdin eToken PRO proxy generation
   (detected platform cygwin)
 Found X.509 certificate on eToken:
   label: (eTCAPI) Jan Just Keijser's NIKHEF ID
   id:    39453945373335312d333545442d343031612d384637302d3238463636393036363042303a30
 Your identity: /O=dutchgrid/O=users/O=nikhef/CN=Jan Just Keijser
 Generating a 512 bit RSA private key
 ..........++++++++++++
 ......++++++++++++
 writing new private key to 'proxykey.QjN408'
 -----
 engine "pkcs11" set.
 Signature ok
 subject=/O=dutchgrid/O=users/O=nikhef/CN=Jan Just Keijser/CN=proxy
 Getting CA Private Key
 PKCS#11 token PIN: 
 Your proxy is valid until: Fri Apr 20 16:51:16 WEST 2007

The default location of your grid proxy is the same as for grid-proxy-init:

  • wherever $X509_USER_PROXY is pointing to

otherwise

  • /tmp/x509up_u<id>, where <id> is your numeric userid.

mkproxy Command-line options

To see the command-line options for the mkproxy script, type 

 ./mkproxy --help

Which will return 

 mkproxy version 1.31
 This script will generate a X509 grid proxy using a public/private
 key pair found on an attached Aladdin eToken PRO.

   Options
   [--help]          Displays usage.
   [--version]       Displays version.
   [--debug]         Enables extra debug output.
   [--quiet]         Quiet mode, minimal output.
   [--limited]       Creates a limited globus proxy.
   [--old]           Creates a legacy globus proxy (default).
   [--gt3]           Creates a pre-RFC3820 compliant proxy.
   [--rfc]           Creates a RFC3820 compliant proxy.
   [--days=N]        Number of days the proxy is valid.
   [--valid=HH:MM]   Proxy is valid for HH hours and MM minutes
                     (default=12:00).
   [--path-length=N] Allow a chain of at most N proxies to be generated
                     from this one (default=2).
   [--bits=N]        Number of bits in key (512, 1024, 2048, default=512).
   [--out=proxyfile] Non-standard location of new proxy cert.
  
   [--slot=N]        Slot number where eToken is located (default=0).
   [--label=string]  (Part of) label of X509 certificate on eToken.
   [--id=string]     (Part of) ID of X509 certificate on eToken.

Note Instead of using '--option=value' you can also use '--option value'.

These option resemble the options of the grid-proxy-init command but there are some additions: 

 --slot=N

specify the slot in which the eToken USB token is insert. If you use only a single token then the default of 0 applies. If you use multiple tokens then increase this number. 

 --label=string
 --id=string

By default, the mkproxy script will use the first X509 certificate found on the eToken to generate a proxy. If there are multiple X509 certificates stored on your eToken then you can specify (part of) the label or of the id of a X509 certificate to select a specific X509 certificate. The RSA private key which is used to create the grid proxy is found by matching the 'id ' of the X509 public certificate with that of the private key. For example, to explicitly select a certificate with a specific ID, use 

 --id=39453945373335312d333545442d343031612d384637302d3238463636393036363042303a30

Fortunately, there is no need to specify the full label or id as found on the eToken to select an X509 certificate. The value passed to the --label option is matched against the X509 certificates on Your Precious eToken using a sed-style regular expression. For example, by specifying 

 --label=NIKHEF

the mkproxy script will select the first X509 certificate on the token with a label matching 'NIKHEF'.

Note on proxy duration

When using the mkproxy.tar.gz tarball all grid proxies generated using the mkproxy script have a duration measured in days, with a minimum of 1 day (i.e 24 hours). This is due to missing functionality in the openssl x509 command, which does not allow you to specify anything more fine-grained, not even a specific end-date.

The etoken-mkproxy RPM includes a patched version of the openssl x509 command. This allows you to specify the proxy duration in hours and minutes (--valid HH:MM).

Advanced mkproxy usage

A more advanced example to use the mkproxy script is 

 ./mkproxy --slot=0 --label=NIK --rfc --bits 1024
 Starting Aladdin eToken PRO proxy generation
  (detected platform fc5)
 Found X.509 certificate on eToken:
   label: (eTCAPI) Jan Just Keijser's NIKHEF ID
   id:    39453945373335312d333545442d343031612d384637302d3238463636393036363042303a30
 Your identity: /O=dutchgrid/O=users/O=nikhef/CN=Jan Just Keijser
 Generating a 1024 bit RSA private key
 ............................++++++
 .........++++++
 writing new private key to 'proxykey.Cz3139'
 -----
 engine "pkcs11" set.
 Signature ok
 subject=/O=dutchgrid/O=users/O=nikhef/CN=Jan Just Keijser/CN=5815075619841
 Getting CA Private Key
 PKCS#11 token PIN:
 Your proxy is valid until: Sat Apr 21 14:10:50 CEST 2007

which

  • selects the first X509 certificate found in slot 0 matching label NIK
  • creates an RFC 3820 compliant proxy
  • using a 1024 bit RSA key

Adding support for other platforms

The mkproxy script makes use of a few external programs which are all publicly available on the Internet. Most of these can be found at the OpenSC website ( http://www.opensc.org ).

The following tools are used by the mkproxy script:

  • the pkcs11-tool command, which in turn depends on the libopensc.so, libscconf.so, libopenct.so and libpcsclite.so libraries
  • the engine-pkcs11.so library , which in turn depends on the libp11.so library
  • the openssl command, preferably version 0.9.8 or higher, with support for dynamic engine loading


To add support for your platform, you can either install the required packages from the web (using rpm/apt/yum/yast/emerge/whatever)

or

you can follow these steps to add support for e.g. ubuntu:

  • create a directory 'ubuntu' in the directory where the mkproxy script is installed
  • in this directory 'ubuntu' create two more directories, 'bin' and 'lib'
  • copy a version of pkcs11-tool that works on your platform to ubuntu/bin
  • copy a version of openssl with dynamic engine loading support that works on your platform to ubuntu/bin
  • copy these libraries to ubuntu/lib:
    • libopensc.so,N
    • libscconf.so.N
    • libopenct.so.N
    • libpcsclite.so.N
    • engine-pkcs11.so
    • libp11.so.N

(where 'N' is the major version number of the library as required and found by using the ldd command

and finally

  • use
 ./mkproxy --platform=ubuntu

to overrule the platform as determined by the mkproxy script.

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