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                 Using SSL
                 =========

The implementation and use of SSL has some differences on Linux and
on Windows.

Linux
=====

SSL support for Qpid-C++ is based on Mozilla's Network Security Services
library. SSL support will be built automatically providing this library
and include files are found at build time.

Broker side SSL Settings (note you can get these by qpidd --help)

SSL Settings:
  --ssl-use-export-policy              Use NSS export policy
  --ssl-cert-password-file PATH        File containing password to use for accessing
                                       certificate database
  --ssl-cert-db PATH                   Path to directory containing certificate
                                       database
  --ssl-cert-name NAME (hostname)      Name of the certificate to use
  --ssl-port PORT (5671)               Port on which to listen for SSL connections
  --ssl-require-client-authentication  Forces clients to authenticate in order 
                                       to establish an SSL connection
  --ssl-sasl-no-dict                   Disables SASL mechanisms that are vulner able to
                                       passive dictionary-based password attacks

The first four of these are also available as client options (where
they must either be in the client config file or set as environment
variables e.g. QPID_SSL_CERT_DB).

To run either the broker or client you need ssl-cert-db-path to point
to the directory where relevant certificate and key databases can be
found.

Certificate databases are set up using certutil (included in the
nss-tools package on fedora). See the NSS site for examples[1] and
full details[2].

For a simple testing you can set up a single db with a single self
signed certificate. E.g (with myhost and mydomain replaced by the
hostname and domainname of the machine in question respectively):

    mkdir test_cert_db
    certutil -N -d test_cert_db -f cert.password
    certutil -S -d test_cert_db -n "myhost.mydomain" \
             -s "CN=myhost.mydomain" -t "CT,," -x \
             -f cert.password -z /usr/bin/certutil

Here cert.password is a file with a password in it that will be needed
for accessing the created db.

The daemon can then be started with something like the following:

./src/qpidd --auth no \
            --ssl-cert-db ./test_cert_db \
            --ssl-cert-password-file ./cert.password \
            --ssl-cert-name myhost.mydomain

then for client set:

QPID_SSL_CERT_DB=./test_cert_db

and run e.g.

./src/tests/perftest --count 10000 -P ssl --port 5671 \
                     --broker myhost.mydomain

When authentication is enabled, the EXTERNAL mechanism will be
available on client authenticated SSL connections. This allows the
clients authorisation id to be taken from the validated client
certificate (it will be the CN with any DCs present appended as the
domain, e.g. CN=bob,DC=acme,DC=com would result in an identity of
bob@acme.com).

[1] http://www.mozilla.org/projects/security/pki/nss/ref/ssl/gtstd.html
[2] http://www.mozilla.org/projects/security/pki/nss/tools/certutil.html


Windows
=======

SSL support for Qpid-C++ on Windows is implemented using the Microsoft
Secure Channel (Schannel) package.  Currently, only registry based
certificates scoped to the local machine are supported on the broker.
The client may specify client certificates in a user scoped store or in
a pkcs#12 file.

For testing purposes, a self signed certificate can be created as
follows (requiring Administrator privilege on more recent versions of
Windows):

  makecert -ss qpidstore -n "CN=myhost.mydomain" -r -sr localmachine myhost.cer

where "qpidstore" is an abitrary certificate store name.  The
resulting output file "myhost.cer" is the public key of the
certificate that will be required by any client that wishes to
authenticate myhost.

To run the server (also as Administrator on recent Windows versions):

  qpidd --ssl-cert-name myhost.mydomain --ssl-cert-store qpidstore [other-args]

On the Windows client side, the SSL support is available without
loading a separate support module.  For each machine or separate user
that will be using qpid, you must import the self signed certificate
as a trusted root.  This can be done from the MMC certificate snapin
or directly using certmgr.exe.  From the main window:

  select "Trusted Root Certification Authorities"
  select "Action" -> "Import..."
  then direct the Certificate Import Wizard to the "myhost.cer" file

To test the setup:

  perftest --count 10000 -P ssl --port 5671 --broker myhost.mydomain

To export the certificate to non Windows clients, note that
"myhost.cer" is the X.509 representation of the public key of the
certificate in DER format.  Import the certificate into the other
clients if they support the DER format.  Otherwise the certificate can
be converted to PEM format using OpenSSL

  openssl x509 -in myhost.cer -inform DER -out myhost.pem -outform PEM

Client certificates operate much the same as for Linux, except for
identifying the certificate storage.  Process environment variables
are used but the certificate name may be set or overridden by its Qpid
Messaging connection option.  For Windows registry stores, you specify
the store:

  QPID_SSL_CERT_STORE=teststore

If you omit the certificate store name, it defaults to the "Personal" or
"MY" store.  For a certificate stored in a pkcs#12 format file, you must
supply the filename and a file containing the password for the
certificate's private key:

  QPID_SSL_CERT_FILENAME=wg444.pfx
  QPID_SSL_CERT_PASSWORD_FILE=pw_wg444.txt

The certificate is specified by its "friendly name", i.e.

  QPID_SSL_CERT_NAME=guest123

as an environment variable, or in the case of a Qpid Messaging
connection option:

  {transport:ssl,sasl-mechanism:EXTERNAL,ssl-cert-name:guest789}