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.
krb_srvname is actually not available anymore as a parameter server-side, since
with gssapi we accept all principals in our keytab. It's still used in libpq for
client side specification.
In passing remove declaration of krb_server_hostname, where all the functionality
was already removed.
Noted by Stephen Frost, though a different solution than his suggestion
krb5 has been deprecated since 8.3, and the recommended way to do
Kerberos authentication is using the GSSAPI authentication method
(which is still fully supported).
libpq retains the ability to identify krb5 authentication, but only
gives an error message about it being unsupported. Since all authentication
is initiated from the backend, there is no need to keep it at all
in the backend.
There's still a lot of room for improvement, but it basically works,
and we need this to be present before we can do anything much with the
writable-foreign-tables patch. So let's commit it and get on with testing.
Shigeru Hanada, reviewed by KaiGai Kohei and Tom Lane
Use the terms "simple bind" and "search+bind" consistently do
distinguish the two modes (better than first mode and second mode in
any case). They were already used in some places, now it's just more
prominent.
Split up the list of options into one for common options and one for
each mode, for clarity.
Add configuration examples for either mode.
Replace unix_socket_directory with unix_socket_directories, which is a list
of socket directories, and adjust postmaster's code to allow zero or more
Unix-domain sockets to be created.
This is mostly a straightforward change, but since the Unix sockets ought
to be created after the TCP/IP sockets for safety reasons (better chance
of detecting a port number conflict), AddToDataDirLockFile needs to be
fixed to support out-of-order updates of data directory lockfile lines.
That's a change that had been foreseen to be necessary someday anyway.
Honza Horak, reviewed and revised by Tom Lane
It turns out the reason we hadn't found out about the portability issues
with our credential-control-message code is that almost no modern platforms
use that code at all; the ones that used to need it now offer getpeereid(),
which we choose first. The last holdout was NetBSD, and they added
getpeereid() as of 5.0. So far as I can tell, the only live platform on
which that code was being exercised was Debian/kFreeBSD, ie, FreeBSD kernel
with Linux userland --- since glibc doesn't provide getpeereid(), we fell
back to the control message code. However, the FreeBSD kernel provides a
LOCAL_PEERCRED socket parameter that's functionally equivalent to Linux's
SO_PEERCRED. That is both much simpler to use than control messages, and
superior because it doesn't require receiving a message from the other end
at just the right time.
Therefore, add code to use LOCAL_PEERCRED when necessary, and rip out all
the credential-control-message code in the backend. (libpq still has such
code so that it can still talk to pre-9.1 servers ... but eventually we can
get rid of it there too.) Clean up related autoconf probes, too.
This means that libpq's requirepeer parameter now works on exactly the same
platforms where the backend supports peer authentication, so adjust the
documentation accordingly.
This removes an overloading of two authentication options where
one is very secure (peer) and one is often insecure (ident). Peer
is also the name used in libpq from 9.1 to specify the same type
of authentication.
Also make initdb select peer for local connections when ident is
chosen, and ident for TCP connections when peer is chosen.
ident keyword in pg_hba.conf is still accepted and maps to peer
authentication.
Block elements with verbatim formatting (literallayout, programlisting,
screen, synopsis) should be aligned at column 0 independent of the surrounding
SGML, because whitespace is significant, and indenting them creates erratic
whitespace in the output. The CSS stylesheets already take care of indenting
the output.
Assorted markup improvements to go along with it.
with database = replication. The previous coding would allow them to match
ordinary records too, but that seems like a recipe for security breaches.
Improve the messages associated with no-such-pg_hba.conf entry to report
replication connections as such, since that's now a critical aspect of
whether the connection matches. Make some cursory improvements in the related
documentation, too.
The endterm attribute is mainly useful when the toolchain does not support
automatic link target text generation for a particular situation. In the
past, this was required by the man page tools for all reference page links,
but that is no longer the case, and it now actually gets in the way of
proper automatic link text generation. The only remaining use cases are
currently xrefs to refsects.
This includes two new kinds of postmaster processes, walsenders and
walreceiver. Walreceiver is responsible for connecting to the primary server
and streaming WAL to disk, while walsender runs in the primary server and
streams WAL from disk to the client.
Documentation still needs work, but the basics are there. We will probably
pull the replication section to a new chapter later on, as well as the
sections describing file-based replication. But let's do that as a separate
patch, so that it's easier to see what has been added/changed. This patch
also adds a new section to the chapter about FE/BE protocol, documenting the
protocol used by walsender/walreceivxer.
Bump catalog version because of two new functions,
pg_last_xlog_receive_location() and pg_last_xlog_replay_location(), for
monitoring the progress of replication.
Fujii Masao, with additional hacking by me
does a search for the user in the directory first, and then binds with
the DN found for this user.
This allows for LDAP logins in scenarios where the DN of the user cannot
be determined simply by prefix and suffix, such as the case where different
users are located in different containers.
The old way of authentication can be significantly faster, so it's kept
as an option.
Robert Fleming and Magnus Hagander
to pass the full username@realm string to the authentication instead of
just the username. This makes it possible to use pg_ident.conf to authenticate
users from multiple realms as different database users.
* make LDAP use this instead of the hacky previous method to specify
the DN to bind as
* make all auth options behave the same when they are not compiled
into the server
* rename "ident maps" to "user name maps", and support them for all
auth methods that provide an external username
This makes a backwards incompatible change in the format of pg_hba.conf
for the ident, PAM and LDAP authentication methods.
each connection. This makes it possible to catch errors in the pg_hba
file when it's being reloaded, instead of silently reloading a broken
file and failing only when a user tries to connect.
This patch also makes the "sameuser" argument to ident authentication
optional.
to validate the realm of the connecting user. By default
it's empty meaning no verification, which is the way
Kerberos authentication has traditionally worked in
PostgreSQL.
against a Unix server, and Windows-specific server-side authentication
using SSPI "negotiate" method (Kerberos or NTLM).
Only builds properly with MSVC for now.
Standard English uses "may", "can", and "might" in different ways:
may - permission, "You may borrow my rake."
can - ability, "I can lift that log."
might - possibility, "It might rain today."
Unfortunately, in conversational English, their use is often mixed, as
in, "You may use this variable to do X", when in fact, "can" is a better
choice. Similarly, "It may crash" is better stated, "It might crash".
Also update two error messages mentioned in the documenation to match.
Peter Eisentraut
Heikki Linnakangas
Magnus Hagander
Tom Lane
Stephen Frost
Bruce Momjian
Andrew Dunstan
Robert Haas
Alvaro Herrera