mellon passes on every attribute received in a SAML assertion as an
Apache variable. By default, the variable is prefixed with "MELLON_".
In some cases, for example when migrating from a different SP to mellon
it might be beneficial to change the prefix. And while using
MellonSetEnvNoPrefix is an option as well, the MellonSetEnvNoPrefix has
to be specified for each variable independently.
Previously there was no way to control the signature algorithm used
when Mellon signed it's SAML messages. It simply defaulted to whatever
the default was in the LassoServer server object. Currently the lasso
default is LASSO_SIGNATURE_METHOD_RSA_SHA1. Some IdP's require a
different or more secure method (e.g. ADFS). This patch allows
controlling the signature method on a per directory basis via the
MellonSignatureMethod configuration directive.
It currently supports the following configuration values which map to
these Lasso enumerated constants (provided these definition exist in
Lasso):
rsa-sha1: LASSO_SIGNATURE_METHOD_RSA_SHA1
rsa-sha256: LASSO_SIGNATURE_METHOD_RSA_SHA256
rsa-sha384: LASSO_SIGNATURE_METHOD_RSA_SHA384
rsa-sha512: LASSO_SIGNATURE_METHOD_RSA_SHA512
configure.ac was modified to test for the existence of the above
Lasso definitions, support is only compiled into Mellon if they
are defined at build time.
Important: This patch also changes the default used by Mellon from
rsa-sha1 to rsa-sha256. This was done because SHA1 is no longer
considered safe, SHA256 is now the current recommendation.
The patch also includes a few corrections in the diagnostics code
where it failed to use CFG_VALUE. Also fixed the diagnostics code when
an unknown value was encounted to print what that unknown value was.
Signed-off-by: John Dennis <jdennis@redhat.com>
Knowing if a SAML operation failed and the reason why is essential to
diagnose problems. The SAML Status Response is always included in all
SAML responses. In addition to the major reason why a transaction
failed it may also include extra expository information giving
additional details. Unfortunately we never logged any of the status
response information when a failure occurred. This patch adds code to
log the status response information.
In addition the patch adds diagnostic logging of received POST data.
Signed-off-by: John Dennis <jdennis@redhat.com>
Commit de853e15 introduced using config.h to define optional build
parameters instead of putting them on the compile command
line. Unfortunately that broke the compilation of
auth_mellon_diagostics.c.
We used to have this:
ifdef ENABLE_DIAGNOSTICS
include "auth_mellon.h"
but the flag ENABLE_DIAGNOSTICS is now defined by including
auth_mellon.h (which includes config.h) hence it would be impossible
for the ENABLE_DIAGNOSTICS to be defined during compilation.
The solution is simple, just reverse the order of the two lines such
that the defines are seen before the #ifdef conditional.
Signed-off-by: John Dennis <jdennis@redhat.com>
Field experience with Mellon has demonstrated there are many
opportunities for deployment problems. Although there are tools such
as browser plugins which can capture SAML messages it's onerous for
site personnel to install and capture the relevant information. The
problem with this approach is further compounded by the fact the
external SAML messages are not correlated to Mellon's
requests/responses. Mellon currently can dump the Lasso session and
SAML Response messages and place them in Apache environment variables,
however these do not appear in the log file. To get them into the log
you have to add custom logging to the Apache config. Another issue is
the dumps are not human readable, they are base64 encoded, anyone
looking at the logs after setting up the custom logging will have to
find the base64 text and then manually copy the text into an external
base64 decoder. At that point you'll discover the XML is not pretty
printed making human interpretation difficult.
The Mellon debug messages written to the Apache error are often
insufficient to diagnose problems. And since the Mellon log messages
are written to the Apache error log they are interspersed with a lot
of non-Mellon message.
Compounding the problem of writing Mellon debug messages to the Apache
error log is the fact Apache log messages have a fixed maximum length
(currently 8192) which is insufficient to completely write out such
things as SAML Assertions, metadata, etc. Apache logging also escapes
all control characters with the consequence line breaks are not
preserved and what was a nicely formatted human readable piece of text
becomes a single line with escape characters and may be truncated.
It would be really nice if we could capture diagnostic information
with these properties:
* All relevant data is collected in exactly one file.
* Only information relevant to Mellon appears in the file.
* All information is human readable (pretty printed, decrypted) with
no need to rely on other tools.
* The diagnostic information is grouped by requests.
* The requests can be cross correlated with other Apache logs because
they utilize the same unique request identifier.
This patch adds diagnostic logging to a independent Mellon diagnostics
log file. Every piece of relevant information is captured, including:
* Request information which includes:
- Request method
- Request URL (raw and processed)
- Scheme
- Port
- Request query parameters
- Server name
- Unique request ID
- process ID, thread ID
- Request headers
* Mellon per directory configuration
A complete dump of the entire am_dir_cfg_rec structure keyed using
both the Mellon directive it is associated with and it's internal
name. This is emitted once on first use for a given URL.
The per directory dump includes the pathname of each file read as
well as the file contents. This includes:
- IdP metadata
- SP metadata
- SP cert
- SP key
- IdP public key file
- IdP CA file
* All session management operations
- cookie
- session lookup
- session creation
- session deletion
- cache management
- cache entry information
* All SAML messages
Each SAML message is decrypted, decoded and XML pretty printed in
human readable form.
* Request pipeline operations
What operations Mellon performs, what decisions it makes and what
data is being used to make those decisions.
* Response
- response status
- response headers
- Apache user name
- auth_type
- all Apache environment variables
Diagnostics can be enabled/disabled both at compile time and run
time. Compile time inclusion of diagnostics is managed with the
ENABLE_DIAGNOSTICS preprocssor symbol. The configure script now accepts
the
--enable-diagnostics and --disable-diagnostics
option. Building with diagnostics is disabled by default, you must
specify --enable-diagnostics to enable the run time option of generating
diagnostics.
The following server config directives have been added (e.g. may be
specified in the main server config area or within a <VirtualHost>
directive). If Mellon was not built with diagnostics enabled then
these config directives are no-ops and their use will generated a
warning in the log file indicating they have been ignored and to be
effective you must builld Mellon with diagnostics enabled.
MellonDiagnosticsFile:
The name of the diagnostics file or pipe,
(default is logs/mellon_diagnostics)
MellonDiagnosticsEnable:
Currently either On or Off but it is designed so it can take other
flags in the future to control what type of information is
reported.
Signed-off-by: John Dennis <jdennis@redhat.com>
Roger Meier
Jakub Hrozek
Olav Morken
John Dennis