The tools.ietf.org site has been decommissioned and replaced by a
number of sites serving various purposes. Links to RFCs and BCPs
are now 301 redirected to their new respective IETF sites. Since
this serves no purpose and only adds network overhead, update our
links to the new locations.
Backpatch to all supported versions.
Discussion: https://postgr.es/m/3C1CEA99-FCED-447D-9858-5A579B4C6687@yesql.se
Backpatch-through: v12
secure_open_gssapi() installed the krb_server_keyfile setting as
KRB5_KTNAME unconditionally, so long as it's not empty. However,
pg_GSS_recvauth() only installed it if KRB5_KTNAME wasn't set already,
leading to a troubling inconsistency: in theory, clients could see
different sets of server principal names depending on whether they
use GSSAPI encryption. Always using krb_server_keyfile seems like
the right thing, so make both places do that. Also fix up
secure_open_gssapi()'s lack of a check for setenv() failure ---
it's unlikely, surely, but security-critical actions are no place
to be sloppy.
Also improve the associated documentation.
This patch does nothing about secure_open_gssapi()'s use of setenv(),
and indeed causes pg_GSS_recvauth() to use it too. That's nominally
against project portability rules, but since this code is only built
with --with-gssapi, I do not feel a need to do something about this
in the back branches. A fix will be forthcoming for HEAD though.
Back-patch to v12 where GSSAPI encryption was introduced. The
dubious behavior in pg_GSS_recvauth() goes back further, but it
didn't have anything to be inconsistent with, so let it be.
Discussion: https://postgr.es/m/2187460.1609263156@sss.pgh.pa.us
Unrecoverable errors detected by GSSAPI encryption can't just be
reported with elog(ERROR) or elog(FATAL), because attempting to
send the error report to the client is likely to lead to infinite
recursion or loss of protocol sync. Instead make this code do what
the SSL encryption code has long done, which is to just report any
such failure to the server log (with elevel COMMERROR), then pretend
we've lost the connection by returning errno = ECONNRESET.
Along the way, fix confusion about whether message translation is done
by pg_GSS_error() or its callers (the latter should do it), and make
the backend version of that function work more like the frontend
version.
Avoid allocating the port->gss struct until it's needed; we surely
don't need to allocate it in the postmaster.
Improve logging of "connection authorized" messages with GSS enabled.
(As part of this, I back-patched the code changes from dc11f31a1.)
Make BackendStatusShmemSize() account for the GSS-related space that
will be allocated by CreateSharedBackendStatus(). This omission
could possibly cause out-of-shared-memory problems with very high
max_connections settings.
Remove arbitrary, pointless restriction that only GSS authentication
can be used on a GSS-encrypted connection.
Improve documentation; notably, document the fact that libpq now
prefers GSS encryption over SSL encryption if both are possible.
Per report from Mikael Gustavsson. Back-patch to v12 where
this code was introduced.
Discussion: https://postgr.es/m/e5b0b6ed05764324a2f3fe7acfc766d5@smhi.se
These were missed when these were added to pg_hba.conf in PG 12;
updates docs and pg_hba.conf.sample.
Reported-by: Arthur Nascimento
Bug: 16380
Discussion: https://postgr.es/m/20200421182736.GG19613@momjian.us
Backpatch-through: 12
The "auth-methods" <sect1> used to include descriptions of all our
authentication methods. Commit 56811e573 promoted its child <sect2>'s
to <sect1>'s, which has advantages but also created some issues:
* The auth-methods page itself is essentially empty/useless.
* Links that pointed to "auth-methods" as a placeholder for all
auth methods were rendered a bit nonsensical.
* DocBook no longer provides a subsection table-of-contents here,
which formerly was a useful if terse summary of available auth methods.
To improve matters, add a handwritten list of all the auth methods.
Per gripe from Dave Cramer. Back-patch to v11 where the previous
commit came in.
Discussion: https://postgr.es/m/CADK3HH+xQLhcPgg=kWqfogtXGGZr-JdSo=x=WQC0PkAVyxUWyQ@mail.gmail.com
Commit 6b76f1bb5 changed all the RADIUS auth parameters to be lists
rather than single values. But its use of SplitIdentifierString
to parse the list format was not very carefully thought through,
because that function thinks it's parsing SQL identifiers, which
means it will (a) downcase the strings and (b) truncate them to
be shorter than NAMEDATALEN. While downcasing should be harmless
for the server names and ports, it's just wrong for the shared
secrets, and probably for the NAS Identifier strings as well.
The truncation aspect is at least potentially a problem too,
though typical values for these parameters would fit in 63 bytes.
Fortunately, we now have a function SplitGUCList that is exactly
the same except for not doing the two unwanted things, so fixing
this is a trivial matter of calling that function instead.
While here, improve the documentation to show how to double-quote
the parameter values. I failed to resist the temptation to do
some copy-editing as well.
Report and patch from Marcos David (bug #16106); doc changes by me.
Back-patch to v10 where the aforesaid commit came in, since this is
arguably a regression from our previous behavior with RADIUS auth.
Discussion: https://postgr.es/m/16106-7d319e4295d08e70@postgresql.org
On both the frontend and backend, prepare for GSSAPI encryption
support by moving common code for error handling into a separate file.
Fix a TODO for handling multiple status messages in the process.
Eliminate the OIDs, which have not been needed for some time.
Add frontend and backend encryption support functions. Keep the
context initiation for authentication-only separate on both the
frontend and backend in order to avoid concerns about changing the
requested flags to include encryption support.
In postmaster, pull GSSAPI authorization checking into a shared
function. Also share the initiator name between the encryption and
non-encryption codepaths.
For HBA, add "hostgssenc" and "hostnogssenc" entries that behave
similarly to their SSL counterparts. "hostgssenc" requires either
"gss", "trust", or "reject" for its authentication.
Similarly, add a "gssencmode" parameter to libpq. Supported values are
"disable", "require", and "prefer". Notably, negotiation will only be
attempted if credentials can be acquired. Move credential acquisition
into its own function to support this behavior.
Add a simple pg_stat_gssapi view similar to pg_stat_ssl, for monitoring
if GSSAPI authentication was used, what principal was used, and if
encryption is being used on the connection.
Finally, add documentation for everything new, and update existing
documentation on connection security.
Thanks to Michael Paquier for the Windows fixes.
Author: Robbie Harwood, with changes to the read/write functions by me.
Reviewed in various forms and at different times by: Michael Paquier,
Andres Freund, David Steele.
Discussion: https://www.postgresql.org/message-id/flat/jlg1tgq1ktm.fsf@thriss.redhat.com
LDAP servers can be advertised on a network with RFC 2782 DNS SRV
records. The OpenLDAP command-line tools automatically try to find
servers that way, if no server name is provided by the user. Teach
PostgreSQL to do the same using OpenLDAP's support functions, when
building with OpenLDAP.
For now, we assume that HAVE_LDAP_INITIALIZE (an OpenLDAP extension
available since OpenLDAP 2.0 and also present in Apple LDAP) implies
that you also have ldap_domain2hostlist() (which arrived in the same
OpenLDAP version and is also present in Apple LDAP).
Author: Thomas Munro
Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/CAEepm=2hAnSfhdsd6vXsM6VZVN0br-FbAZ-O+Swk18S5HkCP=A@mail.gmail.com
This allows a login to require both that the cn of the certificate
matches (like authentication type cert) *and* that another
authentication method (such as password or kerberos) succeeds as well.
The old value of clientcert=1 maps to the new clientcert=verify-ca,
clientcert=0 maps to the new clientcert=no-verify, and the new option
erify-full will add the validation of the CN.
Author: Julian Markwort, Marius Timmer
Reviewed by: Magnus Hagander, Thomas Munro
Update links that resulted in redirects. Most are changes from http to
https, but there are also some other minor edits. (There are still some
redirects where the target URL looks less elegant than the one we
currently have. I have left those as is.)
While ldaptls=1 provides an RFC 4513 conforming way to do LDAP
authentication with TLS encryption, there was an earlier de facto
standard way to do LDAP over SSL called LDAPS. Even though it's not
enshrined in a standard, it's still widely used and sometimes required
by organizations' network policies. There seems to be no reason not to
support it when available in the client library. Therefore, add support
when using OpenLDAP 2.4+ or Windows. It can be configured with
ldapscheme=ldaps or ldapurl=ldaps://...
Add tests for both ways of requesting LDAPS and a test for the
pre-existing ldaptls=1. Modify the 001_auth.pl test for "diagnostic
messages", which was previously relying on the server rejecting
ldaptls=1.
Author: Thomas Munro
Reviewed-By: Peter Eisentraut
Discussion: https://postgr.es/m/CAEepm=1s+pA-LZUjQ-9GQz0Z4rX_eK=DFXAF1nBQ+ROPimuOYQ@mail.gmail.com
Since some preparation work had already been done, the only source
changes left were changing empty-element tags like <xref linkend="foo">
to <xref linkend="foo"/>, and changing the DOCTYPE.
The source files are still named *.sgml, but they are actually XML files
now. Renaming could be considered later.
In the build system, the intermediate step to convert from SGML to XML
is removed. Everything is build straight from the source files again.
The OpenSP (or the old SP) package is no longer needed.
The documentation toolchain instructions are updated and are much
simpler now.
Peter Eisentraut, Alexander Lakhin, Jürgen Purtz
CREATE USER is an alias for CREATE ROLE, not its own command any longer,
so clean up references to the 'sql-createuser' link to go to
'sql-createrole' instead.
In passing, change a few cases of 'CREATE USER' to be
'CREATE ROLE ... LOGIN'. The remaining cases appear reasonable and
also mention the distinction between 'CREATE ROLE' and 'CREATE USER'.
Also, don't say CREATE USER "assumes" LOGIN, but rather "includes".
Patch-by: David G. Johnston, with assumes->includes by me.
Discussion: https://postgr.es/m/CAKFQuwYrbhKV8hH4TEABrDRBwf=gKremF=mLPQ6X2yGqxgFpYA@mail.gmail.com
For DocBook XML compatibility, don't use SGML empty tags (</>) anymore,
replace by the full tag name. Add a warning option to catch future
occurrences.
Alexander Lakhin, Jürgen Purtz
Explain more about how the different password authentication methods and
the password_encryption settings relate to each other, give some
upgrading advice, and set a better link from the release notes.
Reviewed-by: Jeff Janes <jeff.janes@gmail.com>
Before, only filters of the form "(<ldapsearchattribute>=<user>)"
could be used to search an LDAP server. Introduce ldapsearchfilter
so that more general filters can be configured using patterns, like
"(|(uid=$username)(mail=$username))" and "(&(uid=$username)
(objectClass=posixAccount))". Also allow search filters to be included
in an LDAP URL.
Author: Thomas Munro
Reviewed-By: Peter Eisentraut, Mark Cave-Ayland, Magnus Hagander
Discussion: https://postgr.es/m/CAEepm=0XTkYvMci0WRubZcf_1am8=gP=7oJErpsUfRYcKF2gwg@mail.gmail.com
The formatting of the sidebar element didn't carry over to the new tool
chain. Instead of inventing a whole new way of dealing with it, just
convert the one use to a "note".
Per discussion, plain "scram" is confusing because we actually implement
SCRAM-SHA-256 rather than the original SCRAM that uses SHA-1 as the hash
algorithm. If we add support for SCRAM-SHA-512 or some other mechanism in
the SCRAM family in the future, that would become even more confusing.
Most of the internal files and functions still use just "scram" as a
shorthand for SCRMA-SHA-256, but I did change PASSWORD_TYPE_SCRAM to
PASSWORD_TYPE_SCRAM_SHA_256, as that could potentially be used by 3rd
party extensions that hook into the password-check hook.
Michael Paquier did this in an earlier version of the SCRAM patch set
already, but I didn't include that in the version that was committed.
Discussion: https://www.postgresql.org/message-id/fde71ff1-5858-90c8-99a9-1c2427e7bafb@iki.fi
If a user has a SCRAM verifier in pg_authid.rolpassword, there's no reason
we cannot attempt to perform SCRAM authentication instead of MD5. The worst
that can happen is that the client doesn't support SCRAM, and the
authentication will fail. But previously, it would fail for sure, because
we would not even try. SCRAM is strictly more secure than MD5, so there's
no harm in trying it. This allows for a more graceful transition from MD5
passwords to SCRAM, as user passwords can be changed to SCRAM verifiers
incrementally, without changing pg_hba.conf.
Refactor the code in auth.c to support that better. Notably, we now have to
look up the user's pg_authid entry before sending the password challenge,
also when performing MD5 authentication. Also simplify the concept of a
"doomed" authentication. Previously, if a user had a password, but it had
expired, we still performed SCRAM authentication (but always returned error
at the end) using the salt and iteration count from the expired password.
Now we construct a fake salt, like we do when the user doesn't have a
password or doesn't exist at all. That simplifies get_role_password(), and
we can don't need to distinguish the "user has expired password", and
"user does not exist" cases in auth.c.
On second thoughts, also rename uaSASL to uaSCRAM. It refers to the
mechanism specified in pg_hba.conf, and while we use SASL for SCRAM
authentication at the protocol level, the mechanism should be called SCRAM,
not SASL. As a comparison, we have uaLDAP, even though it looks like the
plain 'password' authentication at the protocol level.
Discussion: https://www.postgresql.org/message-id/6425.1489506016@sss.pgh.pa.us
Reviewed-by: Michael Paquier
This changes all the RADIUS related parameters (radiusserver,
radiussecret, radiusport, radiusidentifier) to be plural and to accept a
comma separated list of servers, which will be tried in order.
Reviewed by Adam Brightwell
Logical replication no longer uses the "replication" keyword. It just
matches database entries in the normal way. The "replication" keyword
now only applies to physical replication.
Reviewed-by: Petr Jelinek <petr.jelinek@2ndquadrant.com>
This introduces a new generic SASL authentication method, similar to the
GSS and SSPI methods. The server first tells the client which SASL
authentication mechanism to use, and then the mechanism-specific SASL
messages are exchanged in AuthenticationSASLcontinue and PasswordMessage
messages. Only SCRAM-SHA-256 is supported at the moment, but this allows
adding more SASL mechanisms in the future, without changing the overall
protocol.
Support for channel binding, aka SCRAM-SHA-256-PLUS is left for later.
The SASLPrep algorithm, for pre-processing the password, is not yet
implemented. That could cause trouble, if you use a password with
non-ASCII characters, and a client library that does implement SASLprep.
That will hopefully be added later.
Authorization identities, as specified in the SCRAM-SHA-256 specification,
are ignored. SET SESSION AUTHORIZATION provides more or less the same
functionality, anyway.
If a user doesn't exist, perform a "mock" authentication, by constructing
an authentic-looking challenge on the fly. The challenge is derived from
a new system-wide random value, "mock authentication nonce", which is
created at initdb, and stored in the control file. We go through these
motions, in order to not give away the information on whether the user
exists, to unauthenticated users.
Bumps PG_CONTROL_VERSION, because of the new field in control file.
Patch by Michael Paquier and Heikki Linnakangas, reviewed at different
stages by Robert Haas, Stephen Frost, David Steele, Aleksander Alekseev,
and many others.
Discussion: https://www.postgresql.org/message-id/CAB7nPqRbR3GmFYdedCAhzukfKrgBLTLtMvENOmPrVWREsZkF8g%40mail.gmail.com
Discussion: https://www.postgresql.org/message-id/CAB7nPqSMXU35g%3DW9X74HVeQp0uvgJxvYOuA4A-A3M%2B0wfEBv-w%40mail.gmail.com
Discussion: https://www.postgresql.org/message-id/55192AFE.6080106@iki.fi
This view is designed along the same lines as pg_file_settings, to wit
it shows what is currently in the file, not what the postmaster has
loaded as the active settings. That allows it to be used to pre-vet
edits before issuing SIGHUP. As with the earlier view, go out of our
way to allow errors in the file to be reflected in the view, to assist
that use-case.
(We might at some point invent a view to show the current active settings,
but this is not that patch; and it's not trivial to do.)
Haribabu Kommi, reviewed by Ashutosh Bapat, Michael Paquier, Simon Riggs,
and myself
Discussion: https://postgr.es/m/CAJrrPGerH4jiwpcXT1-46QXUDmNp2QDrG9+-Tek_xC8APHShYw@mail.gmail.com
It is no longer necessary to restart the server to enable, disable,
or reconfigure SSL. Instead, we just create a new SSL_CTX struct
(by re-reading all relevant files) whenever we get SIGHUP. Testing
shows that this is fast enough that it shouldn't be a problem.
In conjunction with that, downgrade the logic that complains about
pg_hba.conf "hostssl" lines when SSL isn't active: now that's just
a warning condition not an error.
An issue that still needs to be addressed is what shall we do with
passphrase-protected server keys? As this stands, the server would
demand the passphrase again on every SIGHUP, which is certainly
impractical. But the case was only barely supported before, so that
does not seem a sufficient reason to hold up committing this patch.
Andreas Karlsson, reviewed by Michael Banck and Michael Paquier
Discussion: https://postgr.es/m/556A6E8A.9030400@proxel.se
We weren't terribly consistent about whether to call Apple's OS "OS X"
or "Mac OS X", and the former is probably confusing to people who aren't
Apple users. Now that Apple has rebranded it "macOS", follow their lead
to establish a consistent naming pattern. Also, avoid the use of the
ancient project name "Darwin", except as the port code name which does not
seem desirable to change. (In short, this patch touches documentation and
comments, but no actual code.)
I didn't touch contrib/start-scripts/osx/, either. I suspect those are
obsolete and due for a rewrite, anyway.
I dithered about whether to apply this edit to old release notes, but
those were responsible for quite a lot of the inconsistencies, so I ended
up changing them too. Anyway, Apple's being ahistorical about this,
so why shouldn't we be?
For some reason this option wasn't discussed at all in client-auth.sgml.
Document it there, and be more explicit about its relationship to the
"cert" authentication method. Per gripe from Srikanth Venkatesh.
I failed to resist the temptation to do some minor wordsmithing in the
same area, too.
Discussion: <20160713110357.1410.30407@wrigleys.postgresql.org>
Describe compat_realm = 0 as "disabled" not "enabled", per discussion
with Christian Ullrich. I failed to resist the temptation to do some
other minor copy-editing in the same area.
These parameters are available for SSPI authentication only, to make
it possible to make it behave more like "normal gssapi", while
making it possible to maintain compatibility.
compat_realm is on by default, but can be turned off to make the
authentication use the full Kerberos realm instead of the NetBIOS name.
upn_username is off by default, and can be turned on to return the users
Kerberos UPN rather than the SAM-compatible name (a user in Active
Directory can have both a legacy SAM-compatible username and a new
Kerberos one. Normally they are the same, but not always)
Author: Christian Ullrich
Reviewed by: Robbie Harwood, Alvaro Herrera, me
Create a "bsd" auth method that works the same as "password" so far as
clients are concerned, but calls the BSD Authentication service to
check the password. This is currently only available on OpenBSD.
Marisa Emerson, reviewed by Thomas Munro
The PAM_RHOST item is set to the remote IP address or host name and can
be used by PAM modules. A pg_hba.conf option is provided to choose
between IP address and resolved host name.
From: Grzegorz Sampolski <grzsmp@gmail.com>
Reviewed-by: Haribabu Kommi <kommi.haribabu@gmail.com>
The default behavior for GSS and SSPI authentication methods has long
been to strip the realm off of the principal, however, this is not a
secure approach in multi-realm environments and the use-case for the
parameter at all has been superseded by the regex-based mapping support
available in pg_ident.conf.
Change the default for include_realm to be '1', meaning that we do
NOT remove the realm from the principal by default. Any installations
which depend on the existing behavior will need to update their
configurations (ideally by leaving include_realm set to 1 and adding a
mapping in pg_ident.conf, but alternatively by explicitly setting
include_realm=0 prior to upgrading). Note that the mapping capability
exists in all currently supported versions of PostgreSQL and so this
change can be done today. Barring that, existing users can update their
configurations today to explicitly set include_realm=0 to ensure that
the prior behavior is maintained when they upgrade.
This needs to be noted in the release notes.
Per discussion with Magnus and Peter.
In investigating yesterday's crash report from Hugo Osvaldo Barrera, I only
looked back as far as commit f3aec2c7f5 where the breakage occurred
(which is why I thought the IPv4-in-IPv6 business was undocumented). But
actually the logic dates back to commit 3c9bb8886d and was simply
broken by erroneous refactoring in the later commit. A bit of archives
excavation shows that we added the whole business in response to a report
that some 2003-era Linux kernels would report IPv4 connections as having
IPv4-in-IPv6 addresses. The fact that we've had no complaints since 9.0
seems to be sufficient confirmation that no modern kernels do that, so
let's just rip it all out rather than trying to fix it.
Do this in the back branches too, thus essentially deciding that our
effective behavior since 9.0 is correct. If there are any platforms on
which the kernel reports IPv4-in-IPv6 addresses as such, yesterday's fix
would have made for a subtle and potentially security-sensitive change in
the effective meaning of IPv4 pg_hba.conf entries, which does not seem like
a good thing to do in minor releases. So let's let the post-9.0 behavior
stand, and change the documentation to match it.
In passing, I failed to resist the temptation to wordsmith the description
of pg_hba.conf IPv4 and IPv6 address entries a bit. A lot of this text
hasn't been touched since we were IPv4-only.
