Commit Graph

82 Commits

Author SHA1 Message Date
Andrew Gierth 02ddd49932 Change floating-point output format for improved performance.
Previously, floating-point output was done by rounding to a specific
decimal precision; by default, to 6 or 15 decimal digits (losing
information) or as requested using extra_float_digits. Drivers that
wanted exact float values, and applications like pg_dump that must
preserve values exactly, set extra_float_digits=3 (or sometimes 2 for
historical reasons, though this isn't enough for float4).

Unfortunately, decimal rounded output is slow enough to become a
noticable bottleneck when dealing with large result sets or COPY of
large tables when many floating-point values are involved.

Floating-point output can be done much faster when the output is not
rounded to a specific decimal length, but rather is chosen as the
shortest decimal representation that is closer to the original float
value than to any other value representable in the same precision. The
recently published Ryu algorithm by Ulf Adams is both relatively
simple and remarkably fast.

Accordingly, change float4out/float8out to output shortest decimal
representations if extra_float_digits is greater than 0, and make that
the new default. Applications that need rounded output can set
extra_float_digits back to 0 or below, and take the resulting
performance hit.

We make one concession to portability for systems with buggy
floating-point input: we do not output decimal values that fall
exactly halfway between adjacent representable binary values (which
would rely on the reader doing round-to-nearest-even correctly). This
is known to be a problem at least for VS2013 on Windows.

Our version of the Ryu code originates from
https://github.com/ulfjack/ryu/ at commit c9c3fb1979, but with the
following (significant) modifications:

 - Output format is changed to use fixed-point notation for small
   exponents, as printf would, and also to use lowercase 'e', a
   minimum of 2 exponent digits, and a mandatory sign on the exponent,
   to keep the formatting as close as possible to previous output.

 - The output of exact midpoint values is disabled as noted above.

 - The integer fast-path code is changed somewhat (since we have
   fixed-point output and the upstream did not).

 - Our project style has been largely applied to the code with the
   exception of C99 declaration-after-statement, which has been
   retained as an exception to our present policy.

 - Most of upstream's debugging and conditionals are removed, and we
   use our own configure tests to determine things like uint128
   availability.

Changing the float output format obviously affects a number of
regression tests. This patch uses an explicit setting of
extra_float_digits=0 for test output that is not expected to be
exactly reproducible (e.g. due to numerical instability or differing
algorithms for transcendental functions).

Conversions from floats to numeric are unchanged by this patch. These
may appear in index expressions and it is not yet clear whether any
change should be made, so that can be left for another day.

This patch assumes that the only supported floating point format is
now IEEE format, and the documentation is updated to reflect that.

Code by me, adapting the work of Ulf Adams and other contributors.

References:
https://dl.acm.org/citation.cfm?id=3192369

Reviewed-by: Tom Lane, Andres Freund, Donald Dong
Discussion: https://postgr.es/m/87r2el1bx6.fsf@news-spur.riddles.org.uk
2019-02-13 15:20:33 +00:00
Tom Lane c64d0cd5ce Use perfect hashing, instead of binary search, for keyword lookup.
We've been speculating for a long time that hash-based keyword lookup
ought to be faster than binary search, but up to now we hadn't found
a suitable tool for generating the hash function.  Joerg Sonnenberger
provided the inspiration, and sample code, to show us that rolling our
own generator wasn't a ridiculous idea.  Hence, do that.

The method used here requires a lookup table of approximately 4 bytes
per keyword, but that's less than what we saved in the predecessor commit
afb0d0712, so it's not a big problem.  The time savings is indeed
significant: preliminary testing suggests that the total time for raw
parsing (flex + bison phases) drops by ~20%.

Patch by me, but it owes its existence to Joerg Sonnenberger;
thanks also to John Naylor for review.

Discussion: https://postgr.es/m/20190103163340.GA15803@britannica.bec.de
2019-01-09 19:47:46 -05:00
Tom Lane afb0d0712f Replace the data structure used for keyword lookup.
Previously, ScanKeywordLookup was passed an array of string pointers.
This had some performance deficiencies: the strings themselves might
be scattered all over the place depending on the compiler (and some
quick checking shows that at least with gcc-on-Linux, they indeed
weren't reliably close together).  That led to very cache-unfriendly
behavior as the binary search touched strings in many different pages.
Also, depending on the platform, the string pointers might need to
be adjusted at program start, so that they couldn't be simple constant
data.  And the ScanKeyword struct had been designed with an eye to
32-bit machines originally; on 64-bit it requires 16 bytes per
keyword, making it even more cache-unfriendly.

Redesign so that the keyword strings themselves are allocated
consecutively (as part of one big char-string constant), thereby
eliminating the touch-lots-of-unrelated-pages syndrome.  And get
rid of the ScanKeyword array in favor of three separate arrays:
uint16 offsets into the keyword array, uint16 token codes, and
uint8 keyword categories.  That reduces the overhead per keyword
to 5 bytes instead of 16 (even less in programs that only need
one of the token codes and categories); moreover, the binary search
only touches the offsets array, further reducing its cache footprint.
This also lets us put the token codes somewhere else than the
keyword strings are, which avoids some unpleasant build dependencies.

While we're at it, wrap the data used by ScanKeywordLookup into
a struct that can be treated as an opaque type by most callers.
That doesn't change things much right now, but it will make it
less painful to switch to a hash-based lookup method, as is being
discussed in the mailing list thread.

Most of the change here is associated with adding a generator
script that can build the new data structure from the same
list-of-PG_KEYWORD header representation we used before.
The PG_KEYWORD lists that plpgsql and ecpg used to embed in
their scanner .c files have to be moved into headers, and the
Makefiles have to be taught to invoke the generator script.
This work is also necessary if we're to consider hash-based lookup,
since the generator script is what would be responsible for
constructing a hash table.

Aside from saving a few kilobytes in each program that includes
the keyword table, this seems to speed up raw parsing (flex+bison)
by a few percent.  So it's worth doing even as it stands, though
we think we can gain even more with a follow-on patch to switch
to hash-based lookup.

John Naylor, with further hacking by me

Discussion: https://postgr.es/m/CAJVSVGXdFVU2sgym89XPL=Lv1zOS5=EHHQ8XWNzFL=mTXkKMLw@mail.gmail.com
2019-01-06 17:02:57 -05:00
Bruce Momjian 97c39498e5 Update copyright for 2019
Backpatch-through: certain files through 9.4
2019-01-02 12:44:25 -05:00
Stephen Frost 8bddc86400 Add application_name to connection authorized msg
The connection authorized message has quite a bit of useful information
in it, but didn't include the application_name (when provided), so let's
add that as it can be very useful.

Note that at the point where we're emitting the connection authorized
message, we haven't processed GUCs, so it's not possible to get this by
using log_line_prefix (which pulls from the GUC).  There's also
something to be said for having this included in the connection
authorized message and then not needing to repeat it for every line, as
having it in log_line_prefix would do.

The GUC cleans the application name to pure-ascii, so do that here too,
but pull out the logic for cleaning up a string into its own function
in common and re-use it from those places, and check_cluster_name which
was doing the same thing.

Author: Don Seiler <don@seiler.us>
Discussion: https://postgr.es/m/CAHJZqBB_Pxv8HRfoh%2BAB4KxSQQuPVvtYCzMg7woNR3r7dfmopw%40mail.gmail.com
2018-09-28 19:04:50 -04:00
Tom Lane ed0cdf0e05 Install a check for mis-linking of src/port and src/common functions.
On ELF-based platforms (and maybe others?) it's possible for a shared
library, when dynamically loaded into the backend, to call the backend
versions of src/port and src/common functions rather than the frontend
versions that are actually linked into the shlib.  This is definitely
not what we want, because the frontend versions often behave slightly
differently.  Up to now it's been "slight" enough that nobody noticed;
but with the addition of SCRAM support functions in src/common, we're
observing crashes due to the difference between palloc and malloc
memory allocation rules, as reported in bug #15367 from Jeremy Evans.

The purpose of this patch is to create a direct test for this type of
mis-linking, so that we know whether any given platform requires extra
measures to prevent using the wrong functions.  If the test fails, it
will lead to connection failures in the contrib/postgres_fdw regression
test.  At the moment, *BSD platforms using ELF format are known to have
the problem and can be expected to fail; but we need to know whether
anything else does, and we need a reliable ongoing check for future
platforms.

Actually fixing the problem will be the subject of later commit(s).

Discussion: https://postgr.es/m/153626613985.23143.4743626885618266803@wrigleys.postgresql.org
2018-09-09 12:23:23 -04:00
Heikki Linnakangas 77291139c7 Remove support for tls-unique channel binding.
There are some problems with the tls-unique channel binding type. It's not
supported by all SSL libraries, and strictly speaking it's not defined for
TLS 1.3 at all, even though at least in OpenSSL, the functions used for it
still seem to work with TLS 1.3 connections. And since we had no
mechanism to negotiate what channel binding type to use, there would be
awkward interoperability issues if a server only supported some channel
binding types. tls-server-end-point seems feasible to support with any SSL
library, so let's just stick to that.

This removes the scram_channel_binding libpq option altogether, since there
is now only one supported channel binding type.

This also removes all the channel binding tests from the SSL test suite.
They were really just testing the scram_channel_binding option, which
is now gone. Channel binding is used if both client and server support it,
so it is used in the existing tests. It would be good to have some tests
specifically for channel binding, to make sure it really is used, and the
different combinations of a client and a server that support or doesn't
support it. The current set of settings we have make it hard to write such
tests, but I did test those things manually, by disabling
HAVE_BE_TLS_GET_CERTIFICATE_HASH and/or
HAVE_PGTLS_GET_PEER_CERTIFICATE_HASH.

I also removed the SCRAM_CHANNEL_BINDING_TLS_END_POINT constant. This is a
matter of taste, but IMO it's more readable to just use the
"tls-server-end-point" string.

Refactor the checks on whether the SSL library supports the functions
needed for tls-server-end-point channel binding. Now the server won't
advertise, and the client won't choose, the SCRAM-SHA-256-PLUS variant, if
compiled with an OpenSSL version too old to support it.

In the passing, add some sanity checks to check that the chosen SASL
mechanism, SCRAM-SHA-256 or SCRAM-SHA-256-PLUS, matches whether the SCRAM
exchange used channel binding or not. For example, if the client selects
the non-channel-binding variant SCRAM-SHA-256, but in the SCRAM message
uses channel binding anyway. It's harmless from a security point of view,
I believe, and I'm not sure if there are some other conditions that would
cause the connection to fail, but it seems better to be strict about these
things and check explicitly.

Discussion: https://www.postgresql.org/message-id/ec787074-2305-c6f4-86aa-6902f98485a4%40iki.fi
2018-08-05 13:44:21 +03:00
Tom Lane 1d96c1b91a Fix incorrect ordering of operations in pg_resetwal and pg_rewind.
Commit c37b3d08c dropped its added GetDataDirectoryCreatePerm call into
the wrong place in pg_resetwal.c, namely after the chdir to DataDir.
That broke invocations using a relative path, as reported by Tushar Ahuja.
We could have left it where it was and changed the argument to be ".",
but that'd result in a rather confusing error message in event of a
failure, so re-ordering seems like a better solution.

Similarly reorder operations in pg_rewind.c.  The issue there is that
it doesn't seem like a good idea to do any actual operations before the
not-root check (on Unix) or the restricted token acquisition (on Windows).
I don't know that this is an actual bug, but I'm definitely not convinced
that it isn't, either.

Assorted other code review for c37b3d08c and da9b580d8: fix some
misspelled or otherwise badly worded comments, put the #include for
<sys/stat.h> where it actually belongs, etc.

Discussion: https://postgr.es/m/aeb9c3a7-3c3f-a57f-1a18-c8d4fcdc2a1f@enterprisedb.com
2018-05-23 10:59:55 -04:00
Tom Lane bdf46af748 Post-feature-freeze pgindent run.
Discussion: https://postgr.es/m/15719.1523984266@sss.pgh.pa.us
2018-04-26 14:47:16 -04:00
Tom Lane af1a949109 Further cleanup of client dependencies on src/include/catalog headers.
In commit 9c0a0de4c, I'd failed to notice that catalog/catalog.h
should also be considered a frontend-unsafe header, because it includes
(and needs) the full form of pg_class.h, not to mention relcache.h.
However, various frontend code was depending on it to get
TABLESPACE_VERSION_DIRECTORY, so refactoring of some sort is called for.

The cleanest answer seems to be to move TABLESPACE_VERSION_DIRECTORY,
as well as the OIDCHARS symbol, to common/relpath.h.  Do that, and mop up
inclusions as necessary.  (I found that quite a few current users of
catalog/catalog.h don't seem to need it at all anymore, apparently as a
result of the refactorings that created common/relpath.[hc].  And
initdb.c needed it only as a route to pg_class_d.h.)

Discussion: https://postgr.es/m/6629.1523294509@sss.pgh.pa.us
2018-04-09 14:39:58 -04:00
Stephen Frost c37b3d08ca Allow group access on PGDATA
Allow the cluster to be optionally init'd with read access for the
group.

This means a relatively non-privileged user can perform a backup of the
cluster without requiring write privileges, which enhances security.

The mode of PGDATA is used to determine whether group permissions are
enabled for directory and file creates.  This method was chosen as it's
simple and works well for the various utilities that write into PGDATA.

Changing the mode of PGDATA manually will not automatically change the
mode of all the files contained therein.  If the user would like to
enable group access on an existing cluster then changing the mode of all
the existing files will be required.  Note that pg_upgrade will
automatically change the mode of all migrated files if the new cluster
is init'd with the -g option.

Tests are included for the backend and all the utilities which operate
on the PG data directory to ensure that the correct mode is set based on
the data directory permissions.

Author: David Steele <david@pgmasters.net>
Reviewed-By: Michael Paquier, with discussion amongst many others.
Discussion: https://postgr.es/m/ad346fe6-b23e-59f1-ecb7-0e08390ad629%40pgmasters.net
2018-04-07 17:45:39 -04:00
Stephen Frost da9b580d89 Refactor dir/file permissions
Consolidate directory and file create permissions for tools which work
with the PG data directory by adding a new module (common/file_perm.c)
that contains variables (pg_file_create_mode, pg_dir_create_mode) and
constants to initialize them (0600 for files and 0700 for directories).

Convert mkdir() calls in the backend to MakePGDirectory() if the
original call used default permissions (always the case for regular PG
directories).

Add tests to make sure permissions in PGDATA are set correctly by the
tools which modify the PG data directory.

Authors: David Steele <david@pgmasters.net>,
         Adam Brightwell <adam.brightwell@crunchydata.com>
Reviewed-By: Michael Paquier, with discussion amongst many others.
Discussion: https://postgr.es/m/ad346fe6-b23e-59f1-ecb7-0e08390ad629%40pgmasters.net
2018-04-07 17:45:39 -04:00
Alvaro Herrera 8d1b805fcc restrict -> pg_restrict
So that it works on MSVC, too.

Author: Michaël Paquier
Discussion: https://postgr.es/m/29889.1520968202@sss.pgh.pa.us
2018-03-15 10:02:59 -03:00
Peter Eisentraut 17bb625017 Move strtoint() to common
Several places used similar code to convert a string to an int, so take
the function that we already had and make it globally available.

Reviewed-by: Michael Paquier <michael@paquier.xyz>
2018-03-13 10:21:09 -04:00
Andres Freund 6d7dc53500 Return implementation defined value if pg_$op_s$bit_overflow overflows.
Some older compilers otherwise sometimes complain about undefined
values, even though the return value should not be used in the
overflow case.  We assume that any decent compiler will optimize away
the unnecessary assignment in performance critical cases.

We do not want to restrain the returned value to a specific value,
e.g. 0 or the wrapped-around value, because some fast ways to
implement overflow detecting math do not easily allow for
that (e.g. msvc intrinsics).  As the function documentation already
documents the returned value in case of intrinsics to be
implementation defined, no documentation has to be updated.

Per complaint from Tom Lane and his buildfarm member prairiedog.

Author: Andres Freund
Discussion: https://postgr.es/m/18169.1513958454@sss.pgh.pa.us
2018-02-14 14:23:57 -08:00
Peter Eisentraut 38d485fdaa Fix up references to scram-sha-256
pg_hba_file_rules erroneously reported this as scram-sha256.  Fix that.

To avoid future errors and confusion, also adjust documentation links
and internal symbols to have a separator between "sha" and "256".

Reported-by: Christophe Courtois <christophe.courtois@dalibo.com>
Author: Michael Paquier <michael.paquier@gmail.com>
2018-01-30 16:50:30 -05:00
Peter Eisentraut d3fb72ea6d Implement channel binding tls-server-end-point for SCRAM
This adds a second standard channel binding type for SCRAM.  It is
mainly intended for third-party clients that cannot implement
tls-unique, for example JDBC.

Author: Michael Paquier <michael.paquier@gmail.com>
2018-01-04 15:29:50 -05:00
Bruce Momjian 9d4649ca49 Update copyright for 2018
Backpatch-through: certain files through 9.3
2018-01-02 23:30:12 -05:00
Peter Eisentraut 25d532698d Move SCRAM-related name definitions to scram-common.h
Mechanism names for SCRAM and channel binding names have been included
in scram.h by the libpq frontend code, and this header references a set
of routines which are only used by the backend.  scram-common.h is on
the contrary usable by both the backend and libpq, so getting those
names from there seems more reasonable.

Author: Michael Paquier <michael.paquier@gmail.com>
2017-12-18 16:59:48 -05:00
Andres Freund 11b8f076c0 Fix a number of copy & paste comment errors in common/int.h.
Author: Christoph Berg
Discussion: https://postgr.es/m/20171214082808.GA5775@msg.df7cb.de
2017-12-14 12:33:48 -08:00
Andres Freund 4d6ad31257 Provide overflow safe integer math inline functions.
It's not easy to get signed integer overflow checks correct and
fast. Therefore abstract the necessary infrastructure into a common
header providing addition, subtraction and multiplication for 16, 32,
64 bit signed integers.

The new macros aren't yet used, but a followup commit will convert
several open coded overflow checks.

Author: Andres Freund, with some code stolen from Greg Stark
Reviewed-By: Robert Haas
Discussion: https://postgr.es/m/20171024103954.ztmatprlglz3rwke@alap3.anarazel.de
2017-12-12 16:55:37 -08:00
Andres Freund fffd651e83 Rewrite strnlen replacement implementation from 8a241792f9.
The previous placement of the fallback implementation in libpgcommon
was problematic, because libpqport functions need strnlen
functionality.

Move replacement into libpgport. Provide strnlen() under its posix
name, instead of pg_strnlen(). Fix stupid configure bug, executing the
test only when compiled with threading support.

Author: Andres Freund
Discussion: https://postgr.es/m/E1e1gR2-0005fB-SI@gemulon.postgresql.org
2017-10-10 14:50:30 -07:00
Andres Freund 8a241792f9 Add pg_strnlen() a portable implementation of strlen.
As the OS version is likely going to be more optimized, fall back to
it if available, as detected by configure.
2017-10-09 15:20:42 -07:00
Peter Eisentraut fe7774144d Increase SCRAM salt length
The original value 12 was set based on RFC 5802 for SCRAM-SHA-1, but RFC
7677 for SCRAM-SHA-256 uses 16, so use that.  (This does not affect the
validity of already stored verifiers.)

Discussion: https://www.postgresql.org/message-id/flat/12cc9297-7e05-932f-d863-765e5626ead4%402ndquadrant.com
2017-08-24 14:04:28 -04:00
Alvaro Herrera 5e3254f086 Update copyright in recently added files 2017-07-26 18:17:18 -04:00
Tom Lane c7b8998ebb Phase 2 of pgindent updates.
Change pg_bsd_indent to follow upstream rules for placement of comments
to the right of code, and remove pgindent hack that caused comments
following #endif to not obey the general rule.

Commit e3860ffa4d wasn't actually using
the published version of pg_bsd_indent, but a hacked-up version that
tried to minimize the amount of movement of comments to the right of
code.  The situation of interest is where such a comment has to be
moved to the right of its default placement at column 33 because there's
code there.  BSD indent has always moved right in units of tab stops
in such cases --- but in the previous incarnation, indent was working
in 8-space tab stops, while now it knows we use 4-space tabs.  So the
net result is that in about half the cases, such comments are placed
one tab stop left of before.  This is better all around: it leaves
more room on the line for comment text, and it means that in such
cases the comment uniformly starts at the next 4-space tab stop after
the code, rather than sometimes one and sometimes two tabs after.

Also, ensure that comments following #endif are indented the same
as comments following other preprocessor commands such as #else.
That inconsistency turns out to have been self-inflicted damage
from a poorly-thought-through post-indent "fixup" in pgindent.

This patch is much less interesting than the first round of indent
changes, but also bulkier, so I thought it best to separate the effects.

Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21 15:19:25 -04:00
Tom Lane e3860ffa4d Initial pgindent run with pg_bsd_indent version 2.0.
The new indent version includes numerous fixes thanks to Piotr Stefaniak.
The main changes visible in this commit are:

* Nicer formatting of function-pointer declarations.
* No longer unexpectedly removes spaces in expressions using casts,
  sizeof, or offsetof.
* No longer wants to add a space in "struct structname *varname", as
  well as some similar cases for const- or volatile-qualified pointers.
* Declarations using PG_USED_FOR_ASSERTS_ONLY are formatted more nicely.
* Fixes bug where comments following declarations were sometimes placed
  with no space separating them from the code.
* Fixes some odd decisions for comments following case labels.
* Fixes some cases where comments following code were indented to less
  than the expected column 33.

On the less good side, it now tends to put more whitespace around typedef
names that are not listed in typedefs.list.  This might encourage us to
put more effort into typedef name collection; it's not really a bug in
indent itself.

There are more changes coming after this round, having to do with comment
indentation and alignment of lines appearing within parentheses.  I wanted
to limit the size of the diffs to something that could be reviewed without
one's eyes completely glazing over, so it seemed better to split up the
changes as much as practical.

Discussion: https://postgr.es/m/E1dAmxK-0006EE-1r@gemulon.postgresql.org
Discussion: https://postgr.es/m/30527.1495162840@sss.pgh.pa.us
2017-06-21 14:39:04 -04:00
Bruce Momjian a6fd7b7a5f Post-PG 10 beta1 pgindent run
perltidy run not included.
2017-05-17 16:31:56 -04:00
Heikki Linnakangas 0557a5dc2c Make SCRAM salts and nonces longer.
The salt is stored base64-encoded. With the old 10 bytes raw length, it was
always padded to 16 bytes after encoding. We might as well use 12 raw bytes
for the salt, and it's still encoded into 16 bytes.

Similarly for the random nonces, use a raw length that's divisible by 3, so
that there's no padding after base64 encoding. Make the nonces longer while
we're at it. 10 bytes was probably enough to prevent replay attacks, but
there's no reason to be skimpy here.

Per suggestion from Álvaro Hernández Tortosa.

Discussion: https://www.postgresql.org/message-id/df8c6e27-4d8e-5281-96e5-131a4e638fc8@8kdata.com
2017-05-05 10:02:13 +03:00
Heikki Linnakangas 8f8b9be51f Add PQencryptPasswordConn function to libpq, use it in psql and createuser.
The new function supports creating SCRAM verifiers, in addition to md5
hashes. The algorithm is chosen based on password_encryption, by default.

This fixes the issue reported by Jeff Janes, that there was previously
no way to create a SCRAM verifier with "\password".

Michael Paquier and me

Discussion: https://www.postgresql.org/message-id/CAMkU%3D1wfBgFPbfAMYZQE78p%3DVhZX7nN86aWkp0QcCp%3D%2BKxZ%3Dbg%40mail.gmail.com
2017-05-03 11:19:07 +03:00
Heikki Linnakangas d981074c24 Misc SCRAM code cleanups.
* Move computation of SaltedPassword to a separate function from
  scram_ClientOrServerKey(). This saves a lot of cycles in libpq, by
  computing SaltedPassword only once per authentication. (Computing
  SaltedPassword is expensive by design.)

* Split scram_ClientOrServerKey() into two functions. Improves
  readability, by making the calling code less verbose.

* Rename "server proof" to "server signature", to better match the
  nomenclature used in RFC 5802.

* Rename SCRAM_SALT_LEN to SCRAM_DEFAULT_SALT_LEN, to make it more clear
  that the salt can be of any length, and the constant only specifies how
  long a salt we use when we generate a new verifier. Also rename
  SCRAM_ITERATIONS_DEFAULT to SCRAM_DEFAULT_ITERATIONS, for consistency.

These things caught my eye while working on other upcoming changes.
2017-04-28 15:22:38 +03:00
Peter Eisentraut 0cb2e51992 Avoid using a C++ keyword in header file
per cpluspluscheck
2017-04-07 16:32:02 -04:00
Heikki Linnakangas 60f11b87a2 Use SASLprep to normalize passwords for SCRAM authentication.
An important step of SASLprep normalization, is to convert the string to
Unicode normalization form NFKC. Unicode normalization requires a fairly
large table of character decompositions, which is generated from data
published by the Unicode consortium. The script to generate the table is
put in src/common/unicode, as well test code for the normalization.
A pre-generated version of the tables is included in src/include/common,
so you don't need the code in src/common/unicode to build PostgreSQL, only
if you wish to modify the normalization tables.

The SASLprep implementation depends on the UTF-8 functions from
src/backend/utils/mb/wchar.c. So to use it, you must also compile and link
that. That doesn't change anything for the current users of these
functions, the backend and libpq, as they both already link with wchar.o.
It would be good to move those functions into a separate file in
src/commmon, but I'll leave that for another day.

No documentation changes included, because there is no details on the
SCRAM mechanism in the docs anyway. An overview on that in the protocol
specification would probably be good, even though SCRAM is documented in
detail in RFC5802. I'll write that as a separate patch. An important thing
to mention there is that we apply SASLprep even on invalid UTF-8 strings,
to support other encodings.

Patch by Michael Paquier and me.

Discussion: https://www.postgresql.org/message-id/CAB7nPqSByyEmAVLtEf1KxTRh=PWNKiWKEKQR=e1yGehz=wbymQ@mail.gmail.com
2017-04-07 14:56:05 +03:00
Heikki Linnakangas 07044efe00 Remove bogus SCRAM_ITERATION_LEN constant.
It was not used for what the comment claimed, at all. It was actually used
as the 'base' argument to strtol(), when reading the iteration count. We
don't need a constant for base-10, so remove it.
2017-04-06 17:41:48 +03:00
Tom Lane df1a699e5b Fix integer-overflow problems in interval comparison.
When using integer timestamps, the interval-comparison functions tried
to compute the overall magnitude of an interval as an int64 number of
microseconds.  As reported by Frazer McLean, this overflows for intervals
exceeding about 296000 years, which is bad since we nominally allow
intervals many times larger than that.  That results in wrong comparison
results, and possibly in corrupted btree indexes for columns containing
such large interval values.

To fix, compute the magnitude as int128 instead.  Although some compilers
have native support for int128 calculations, many don't, so create our
own support functions that can do 128-bit addition and multiplication
if the compiler support isn't there.  These support functions are designed
with an eye to allowing the int128 code paths in numeric.c to be rewritten
for use on all platforms, although this patch doesn't do that, or even
provide all the int128 primitives that will be needed for it.

Back-patch as far as 9.4.  Earlier releases did not guard against overflow
of interval values at all (commit 146604ec4 fixed that), so it seems not
very exciting to worry about overly-large intervals for them.

Before 9.6, we did not assume that unreferenced "static inline" functions
would not draw compiler warnings, so omit functions not directly referenced
by timestamp.c, the only present consumer of int128.h.  (We could have
omitted these functions in HEAD too, but since they were written and
debugged on the way to the present patch, and they look likely to be needed
by numeric.c, let's keep them in HEAD.)  I did not bother to try to prevent
such warnings in a --disable-integer-datetimes build, though.

Before 9.5, configure will never define HAVE_INT128, so the part of
int128.h that exploits a native int128 implementation is dead code in the
9.4 branch.  I didn't bother to remove it, thinking that keeping the file
looking similar in different branches is more useful.

In HEAD only, add a simple test harness for int128.h in src/tools/.

In back branches, this does not change the float-timestamps code path.
That's not subject to the same kind of overflow risk, since it computes
the interval magnitude as float8.  (No doubt, when this code was originally
written, overflow was disregarded for exactly that reason.)  There is a
precision hazard instead :-(, but we'll avert our eyes from that question,
since no complaints have been reported and that code's deprecated anyway.

Kyotaro Horiguchi and Tom Lane

Discussion: https://postgr.es/m/1490104629.422698.918452336.26FA96B7@webmail.messagingengine.com
2017-04-05 23:51:27 -04:00
Andrew Dunstan 96a7128b7b Sync pg_dump and pg_dumpall output
Before exiting any files are fsync'ed. A --no-sync option is also
provided for a faster exit if desired.

Michael Paquier.

Reviewed by Albe Laurenz

Discussion: https://postgr.es/m/CAB7nPqS1uZ=Ov+UruW6jr3vB-S_DLVMPc0dQpV-fTDjmm0ZQMg@mail.gmail.com
2017-03-22 10:20:13 -04:00
Heikki Linnakangas 55acfcbffd Fix comments in SCRAM-SHA-256 patch.
Amit Kapila.
2017-03-07 15:24:27 +02:00
Heikki Linnakangas 818fd4a67d Support SCRAM-SHA-256 authentication (RFC 5802 and 7677).
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
2017-03-07 14:25:40 +02:00
Heikki Linnakangas 273c458a2b Refactor SHA2 functions and move them to src/common/.
This way both frontend and backends can use them. The functions are taken
from pgcrypto, which now fetches the source files it needs from
src/common/.

A new interface is designed for the SHA2 functions, which allow linking
to either OpenSSL or the in-core stuff taken from KAME as needed.

Michael Paquier, reviewed by Robert Haas.

Discussion: https://www.postgresql.org/message-id/CAB7nPqTGKuTM5jiZriHrNaQeVqp5e_iT3X4BFLWY_HyHxLvySQ%40mail.gmail.com
2017-03-07 14:23:49 +02:00
Heikki Linnakangas dbd69118c0 Replace isMD5() with a more future-proof way to check if pw is encrypted.
The rule is that if pg_authid.rolpassword begins with "md5" and has the
right length, it's an MD5 hash, otherwise it's a plaintext password. The
idiom has been to use isMD5() to check for that, but that gets awkward,
when we add new kinds of verifiers, like the verifiers for SCRAM
authentication in the pending SCRAM patch set. Replace isMD5() with a new
get_password_type() function, so that when new verifier types are added, we
don't need to remember to modify every place that currently calls isMD5(),
to also recognize the new kinds of verifiers.

Also, use the new plain_crypt_verify function in passwordcheck, so that it
doesn't need to know about MD5, or in the future, about other kinds of
hashes or password verifiers.

Reviewed by Michael Paquier and Peter Eisentraut.

Discussion: https://www.postgresql.org/message-id/2d07165c-1793-e243-a2a9-e45b624c7580@iki.fi
2017-02-01 13:11:37 +02:00
Bruce Momjian 1d25779284 Update copyright via script for 2017 2017-01-03 13:48:53 -05:00
Robert Haas f82ec32ac3 Rename "pg_xlog" directory to "pg_wal".
"xlog" is not a particularly clear abbreviation for "write-ahead log",
and it sometimes confuses users into believe that the contents of the
"pg_xlog" directory are not critical data, leading to unpleasant
consequences.  So, rename the directory to "pg_wal".

This patch modifies pg_upgrade and pg_basebackup to understand both
the old and new directory layouts; the former is necessary given the
purpose of the tool, while the latter merely avoids an unnecessary
backward-compatibility break.

We may wish to consider renaming other programs, switches, and
functions which still use the old "xlog" naming to also refer to
"wal".  However, that's still under discussion, so let's do just this
much for now.

Discussion: CAB7nPqTeC-8+zux8_-4ZD46V7YPwooeFxgndfsq5Rg8ibLVm1A@mail.gmail.com

Michael Paquier
2016-10-20 11:32:18 -04:00
Peter Eisentraut bc34223bc1 pg_basebackup pg_receivexlog: Issue fsync more carefully
Several places weren't careful about fsyncing in the way.  See 1d4a0ab1
and 606e0f98 for details about required fsyncs.

This adds a couple of functions in src/common/ that have an equivalent
in the backend: durable_rename(), fsync_parent_path()

From: Michael Paquier <michael.paquier@gmail.com>
2016-09-29 12:00:00 -04:00
Peter Eisentraut bf5bb2e85b Move fsync routines of initdb into src/common/
The intention is to used those in other utilities such as pg_basebackup
and pg_receivexlog.

From: Michael Paquier <michael.paquier@gmail.com>
2016-09-29 12:00:00 -04:00
Peter Eisentraut e79e6c4da1 Fix CRC check handling in get_controlfile
The previous patch broke this by returning NULL for a failed CRC check,
which pg_controldata would then try to read.  Fix by returning the
result of the CRC check in a separate argument.

Michael Paquier and myself
2016-09-28 12:00:00 -04:00
Peter Eisentraut c1dc51d484 pg_ctl: Detect current standby state from pg_control
pg_ctl used to determine whether a server was in standby mode by looking
for a recovery.conf file.  With this change, it instead looks into
pg_control, which is potentially more accurate.  There are also
occasional discussions about removing recovery.conf, so this removes one
dependency.

Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
2016-09-21 12:00:00 -04:00
Heikki Linnakangas ec136d19b2 Move code shared between libpq and backend from backend/libpq/ to common/.
When building libpq, ip.c and md5.c were symlinked or copied from
src/backend/libpq into src/interfaces/libpq, but now that we have a
directory specifically for routines that are shared between the server and
client binaries, src/common/, move them there.

Some routines in ip.c were only used in the backend. Keep those in
src/backend/libpq, but rename to ifaddr.c to avoid confusion with the file
that's now in common.

Fix the comment in src/common/Makefile to reflect how libpq actually links
those files.

There are two more files that libpq symlinks directly from src/backend:
encnames.c and wchar.c. I don't feel compelled to move those right now,
though.

Patch by Michael Paquier, with some changes by me.

Discussion: <69938195-9c76-8523-0af8-eb718ea5b36e@iki.fi>
2016-09-02 13:49:59 +03:00
Robert Haas 4bc424b968 pgindent run for 9.6 2016-06-09 18:02:36 -04:00
Tom Lane c2d1eea9e7 Avoid PGDLLIMPORT for simple local references in frontend programs.
I was wondering if this would be an issue, and buildfarm member frogmouth
says it is.
2016-03-23 23:26:44 -04:00
Tom Lane 2c6af4f442 Move keywords.c/kwlookup.c into src/common/.
Now that we have src/common/ for code shared between frontend and backend,
we can get rid of (most of) the klugy ways that the keyword table and
keyword lookup code were formerly shared between different uses.
This is a first step towards a more general plan of getting rid of
special-purpose kluges for sharing code in src/bin/.

I chose to merge kwlookup.c back into keywords.c, as it once was, and
always has been so far as keywords.h is concerned.  We could have
kept them separate, but there is noplace that uses ScanKeywordLookup
without also wanting access to the backend's keyword list, so there
seems little point.

ecpg is still a bit weird, but at least now the trickiness is documented.

I think that the MSVC build script should require no adjustments beyond
what's done here ... but we'll soon find out.
2016-03-23 20:22:08 -04:00