PUSP from MyProxy

Introduction

This page describes how one can configure a MyProxy server (in 'CA' mode) to produce PUSP proxies (see EGI wiki on PUSP) instead of End-Entity Certificates.

'Simple CA' setup

Create a MyProxy 'simple CA' directory structure:

/var/lib/globus/simple_robotca/
/var/lib/globus/simple_robotca/newcerts/
/var/lib/globus/simple_robotca/private/

Now store the robot certificate and key as if they are CA certificate and key:

/var/lib/globus/simple_robotca/cacert.pem
/var/lib/globus/simple_robotca/private/cakey.pem

Initialize a new 'CA':

touch /var/lib/globus/simple_robotca/index.txt
echo 01 > /var/lib/globus/simple_robotca/serial

Configuration of the MyProxy server

Edit the server configuration /etc/myproxy-server.config to look something like:

cert_dir /etc/grid-security/certificates

# Robot certificate and private key, update paths where needed
certificate_issuer_cert /var/lib/globus/simple_robotca/cacert.pem
certificate_issuer_key /var/lib/globus/simple_robotca/private/cakey.pem
# Set the correct robot private key password
certificate_issuer_key_passphrase "<ROBOT CERTIFICATE PASSPHRASE>"

certificate_serialfile /var/lib/globus/simple_robotca/serial
certificate_out_dir /var/lib/globus/simple_robotca/newcerts

# Next option is needed to include the robot EEC in the returned proxy chain
certificate_issuer_subca_certfile /var/lib/globus/simple_robotca/cacert.pem

# Script to produce the correct PUSP subject DN
certificate_mapapp /opt/myproxy/bin/myproxy-certificate-mapapp

# Extensions to create a valid RFC proxy certificate
certificate_extfile /opt/myproxy/share/etc/proxy_extensions.cnf

Extra files used to create the PUSP

Mapping script

The contents of the mapping script myproxy-certificate-mapapp is something like:

#!/bin/sh
username=$1
if [ X"$username" = X ]; then
    # no username given
    exit 1
fi
# DN must match robot DN.
echo "/DC=org/DC=terena/DC=tcs/O=Nikhef/OU=Robot/CN=Robot - Marvin/CN=user:${username}"
exit 0

Certificate extensions file

And the proxy_extensions.cnf contains something like:

keyUsage = critical,digitalSignature,keyEncipherment
1.3.6.1.5.5.7.1.14 = critical,ASN1:SEQUENCE:rfc3820_seq_sect_infinite

[ rfc3820_seq_sect_infinite ]
field1 = SEQUENCE:normal_policy

[ normal_policy ]
p1 = OID:1.3.6.1.5.5.7.21.1

A more generic file would be:

keyUsage = critical,digitalSignature,keyEncipherment
1.3.6.1.5.5.7.1.14 = critical,ASN1:SEQUENCE:$ENV::PROXY_INFO

[ rfc3820_seq_sect_infinite ]
field1 = SEQUENCE:$ENV::PROXY_POLICY

[ rfc3820_seq_sect ]
field1 = INTEGER:$ENV::PROXY_PATHLENGTH
field2 = SEQUENCE:$ENV::PROXY_POLICY

[ normal_policy ]
p1 = OID:1.3.6.1.5.5.7.21.1

[ limited_policy ]
p1 = OID:1.3.6.1.4.1.3536.1.1.1.9

where PROXY_INFO, PROXY_PATHLENGTH and PROXY_POLICY should be defined as environment variables, e.g. in /etc/sysconfig/myproxy-server For example:

export PROXY_INFO=rfc3820_seq_sect
export PROXY_PATHLENGTH=42
export PROXY_POLICY=limited_policy

which would result in limited RFC proxies with a maximum proxyPathLength constraint of 42.