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* Improve error message for rejecting RETURNING clauses with dropped columns.Tom Lane2016-02-29
| | | | | | | | | | | | | | | This error message was written with only ON SELECT rules in mind, but since then we also made RETURNING-clause targetlists go through the same logic. This means that you got a rather off-topic error message if you tried to add a rule with RETURNING to a table having dropped columns. Ideally we'd just support that, but some preliminary investigation says that it might be a significant amount of work. Seeing that Nicklas Avén's complaint is the first one we've gotten about this in the ten years or so that the code's been like that, I'm unwilling to put much time into it. Instead, improve the error report by issuing a different message for RETURNING cases, and revise the associated comment based on this investigation. Discussion: 1456176604.17219.9.camel@jordogskog.no
* Update copyright for 2016Bruce Momjian2016-01-02
| | | | Backpatch certain files through 9.1
* Put back one copyObject() in rewriteTargetView().Tom Lane2015-12-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 6f8cb1e23485bd6d tried to centralize rewriteTargetView's copying of a target view's Query struct. However, it ignored the fact that the jointree->quals field was used twice. This only accidentally failed to fail immediately because the same ChangeVarNodes mutation is applied in both cases, so that we end up with logically identical expression trees for both uses (and, as the code stands, the second ChangeVarNodes call actually does nothing). However, we end up linking *physically* identical expression trees into both an RTE's securityQuals list and the WithCheckOption list. That's pretty dangerous, mainly because prepsecurity.c is utterly cavalier about further munging such structures without copying them first. There may be no live bug in HEAD as a consequence of the fact that we apply preprocess_expression in between here and prepsecurity.c, and that will make a copy of the tree anyway. Or it may just be that the regression tests happen to not trip over it. (I noticed this only because things fell over pretty badly when I tried to relocate the planner's call of expand_security_quals to before expression preprocessing.) In any case it's very fragile because if anyone tried to make the securityQuals and WithCheckOption trees diverge before we reach preprocess_expression, it would not work. The fact that the current code will preprocess securityQuals and WithCheckOptions lists at completely different times in different query levels does nothing to increase my trust that that can't happen. In view of the fact that 9.5.0 is almost upon us and the aforesaid commit has seen exactly zero field testing, the prudent course is to make an extra copy of the quals so that the behavior is not different from what has been in the field during beta.
* Make viewquery a copy in rewriteTargetView()Stephen Frost2015-12-21
| | | | | | | | | | | | | | | Rather than expect the Query returned by get_view_query() to be read-only and then copy bits and pieces of it out, simply copy the entire structure when we get it. This addresses an issue where AcquireRewriteLocks, which is called by acquireLocksOnSubLinks(), scribbles on the parsetree passed in, which was actually an entry in relcache, leading to segfaults with certain view definitions. This also future-proofs us a bit for anyone adding more code to this path. The acquireLocksOnSubLinks() was added in commit c3e0ddd40. Back-patch to 9.3 as that commit was.
* Get rid of the planner's LateralJoinInfo data structure.Tom Lane2015-12-11
| | | | | | | | | | | | | | | | | | | | I originally modeled this data structure on SpecialJoinInfo, but after commit acfcd45cacb6df23 that looks like a pretty poor decision. All we really need is relid sets identifying laterally-referenced rels; and most of the time, what we want to know about includes indirect lateral references, a case the LateralJoinInfo data was unsuited to compute with any efficiency. The previous commit redefined RelOptInfo.lateral_relids as the transitive closure of lateral references, so that it easily supports checking indirect references. For the places where we really do want just direct references, add a new RelOptInfo field direct_lateral_relids, which is easily set up as a copy of lateral_relids before we perform the transitive closure calculation. Then we can just drop lateral_info_list and LateralJoinInfo and the supporting code. This makes the planner's handling of lateral references noticeably more efficient, and shorter too. Such a change can't be back-patched into stable branches for fear of breaking extensions that might be looking at the planner's data structures; but it seems not too late to push it into 9.5, so I've done so.
* Apply SELECT policies in INSERT/UPDATE+RETURNINGStephen Frost2015-10-05
| | | | | | | | Similar to 7d8db3e, given that INSERT+RETURNING requires SELECT rights on the table, apply the SELECT policies as WCOs to the tuples being inserted. Apply the same logic to UPDATE+RETURNING. Back-patch to 9.5 where RLS was added.
* Include policies based on ACLs neededStephen Frost2015-09-30
| | | | | | | | | | | | | | | | | | | | | | | When considering which policies should be included, rather than look at individual bits of the query (eg: if a RETURNING clause exists, or if a WHERE clause exists which is referencing the table, or if it's a FOR SHARE/UPDATE query), consider any case where we've determined the user needs SELECT rights on the relation while doing an UPDATE or DELETE to be a case where we apply SELECT policies, and any case where we've deteremind that the user needs UPDATE rights on the relation while doing a SELECT to be a case where we apply UPDATE policies. This simplifies the logic and addresses concerns that a user could use UPDATE or DELETE with a WHERE clauses to determine if rows exist, or they could use SELECT .. FOR UPDATE to lock rows which they are not actually allowed to modify through UPDATE policies. Use list_append_unique() to avoid adding the same quals multiple times, as, on balance, the cost of checking when adding the quals will almost always be cheaper than keeping them and doing busywork for each tuple during execution. Back-patch to 9.5 where RLS was added.
* Enforce ALL/SELECT policies in RETURNING for RLSStephen Frost2015-09-15
| | | | | | | | | | | | For the UPDATE/DELETE RETURNING case, filter the records which are not visible to the user through ALL or SELECT policies from those considered for the UPDATE or DELETE. This is similar to how the GRANT system works, which prevents RETURNING unless the caller has SELECT rights on the relation. Per discussion with Robert, Dean, Tom, and Kevin. Back-patch to 9.5 where RLS was introduced.
* RLS refactoringStephen Frost2015-09-15
| | | | | | | | | | | | | | | | This refactors rewrite/rowsecurity.c to simplify the handling of the default deny case (reducing the number of places where we check for and add the default deny policy from three to one) by splitting up the retrival of the policies from the application of them. This also allowed us to do away with the policy_id field. A policy_name field was added for WithCheckOption policies and is used in error reporting, when available. Patch by Dean Rasheed, with various mostly cosmetic changes by me. Back-patch to 9.5 where RLS was introduced to avoid unnecessary differences, since we're still in alpha, per discussion with Robert.
* Lock all relations referred to in updatable viewsStephen Frost2015-09-08
| | | | | | | | | | Even views considered "simple" enough to be automatically updatable may have mulitple relations involved (eg: in a where clause). We need to make sure and lock those relations when rewriting the query. Back-patch to 9.3 where updatable views were added. Pointed out by Andres, patch thanks to Dean Rasheed.
* Ensure locks are acquired on RLS-added relationsStephen Frost2015-08-28
| | | | | | | | During fireRIRrules(), get_row_security_policies can add to securityQuals and withCheckOptions. Make sure to lock any relations added at that point and before firing RIR rules on those expressions. Back-patch to 9.5 where RLS was added.
* Clarify what some historic terms in rewriteHandler.c mean.Andres Freund2015-08-28
| | | | Discussion: 20150827131352.GF2435@awork2.anarazel.de
* RLS: Keep deny policy when only restrictive existStephen Frost2015-08-03
| | | | | | | | | | | | | | | Only remove the default deny policy when a permissive policy exists (either from the hook or defined by the user). If only restrictive policies exist then no rows will be visible, as restrictive policies shouldn't make rows visible. To address this requirement, a single "USING (true)" permissive policy can be created. Update the test_rls_hooks regression tests to create the necessary "USING (true)" permissive policy. Back-patch to 9.5 where RLS was added. Per discussion with Dean.
* Use appropriate command type when retrieving relation's policies.Joe Conway2015-07-30
| | | | | | | | | | | | | When retrieving policies, if not working on the root target relation, we actually want the relation's SELECT policies, regardless of the top level query command type. For example in UPDATE t1...FROM t2 we need to apply t1's UPDATE policies and t2's SELECT policies. Previously top level query command type was applied to all relations, which was wrong. Add some regression coverage to ensure we don't violate this principle in the future. Report and patch by Dean Rasheed. Cherry picked from larger refactoring patch and tweaked by me. Back-patched to 9.5 where RLS was introduced.
* Disallow converting a table to a view if row security is present.Joe Conway2015-07-28
| | | | | | | | | | | | When DefineQueryRewrite() is about to convert a table to a view, it checks the table for features unavailable to views. For example, it rejects tables having triggers. It omits to reject tables having relrowsecurity or a pg_policy record. Fix that. To faciliate the repair, invent relation_has_policies() which indicates the presence of policies on a relation even when row security is disabled for that relation. Reported by Noah Misch. Patch by me, review by Stephen Frost. Back-patch to 9.5 where RLS was introduced.
* Plug RLS related information leak in pg_stats view.Joe Conway2015-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The pg_stats view is supposed to be restricted to only show rows about tables the user can read. However, it sometimes can leak information which could not otherwise be seen when row level security is enabled. Fix that by not showing pg_stats rows to users that would be subject to RLS on the table the row is related to. This is done by creating/using the newly introduced SQL visible function, row_security_active(). Along the way, clean up three call sites of check_enable_rls(). The second argument of that function should only be specified as other than InvalidOid when we are checking as a different user than the current one, as in when querying through a view. These sites were passing GetUserId() instead of InvalidOid, which can cause the function to return incorrect results if the current user has the BYPASSRLS privilege and row_security has been set to OFF. Additionally fix a bug causing RI Trigger error messages to unintentionally leak information when RLS is enabled, and other minor cleanup and improvements. Also add WITH (security_barrier) to the definition of pg_stats. Bumped CATVERSION due to new SQL functions and pg_stats view definition. Back-patch to 9.5 where RLS was introduced. Reported by Yaroslav. Patch by Joe Conway and Dean Rasheed with review and input by Michael Paquier and Stephen Frost.
* Redesign tablesample method API, and do extensive code review.Tom Lane2015-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The original implementation of TABLESAMPLE modeled the tablesample method API on index access methods, which wasn't a good choice because, without specialized DDL commands, there's no way to build an extension that can implement a TSM. (Raw inserts into system catalogs are not an acceptable thing to do, because we can't undo them during DROP EXTENSION, nor will pg_upgrade behave sanely.) Instead adopt an API more like procedural language handlers or foreign data wrappers, wherein the only SQL-level support object needed is a single handler function identified by having a special return type. This lets us get rid of the supporting catalog altogether, so that no custom DDL support is needed for the feature. Adjust the API so that it can support non-constant tablesample arguments (the original coding assumed we could evaluate the argument expressions at ExecInitSampleScan time, which is undesirable even if it weren't outright unsafe), and discourage sampling methods from looking at invisible tuples. Make sure that the BERNOULLI and SYSTEM methods are genuinely repeatable within and across queries, as required by the SQL standard, and deal more honestly with methods that can't support that requirement. Make a full code-review pass over the tablesample additions, and fix assorted bugs, omissions, infelicities, and cosmetic issues (such as failure to put the added code stanzas in a consistent ordering). Improve EXPLAIN's output of tablesample plans, too. Back-patch to 9.5 so that we don't have to support the original API in production.
* Manual cleanup of pgindent results.Tom Lane2015-05-24
| | | | | | Fix some places where pgindent did silly stuff, often because project style wasn't followed to begin with. (I've not touched the atomics headers, though.)
* pgindent run for 9.5Bruce Momjian2015-05-23
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* Support GROUPING SETS, CUBE and ROLLUP.Andres Freund2015-05-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This SQL standard functionality allows to aggregate data by different GROUP BY clauses at once. Each grouping set returns rows with columns grouped by in other sets set to NULL. This could previously be achieved by doing each grouping as a separate query, conjoined by UNION ALLs. Besides being considerably more concise, grouping sets will in many cases be faster, requiring only one scan over the underlying data. The current implementation of grouping sets only supports using sorting for input. Individual sets that share a sort order are computed in one pass. If there are sets that don't share a sort order, additional sort & aggregation steps are performed. These additional passes are sourced by the previous sort step; thus avoiding repeated scans of the source data. The code is structured in a way that adding support for purely using hash aggregation or a mix of hashing and sorting is possible. Sorting was chosen to be supported first, as it is the most generic method of implementation. Instead of, as in an earlier versions of the patch, representing the chain of sort and aggregation steps as full blown planner and executor nodes, all but the first sort are performed inside the aggregation node itself. This avoids the need to do some unusual gymnastics to handle having to return aggregated and non-aggregated tuples from underlying nodes, as well as having to shut down underlying nodes early to limit memory usage. The optimizer still builds Sort/Agg node to describe each phase, but they're not part of the plan tree, but instead additional data for the aggregation node. They're a convenient and preexisting way to describe aggregation and sorting. The first (and possibly only) sort step is still performed as a separate execution step. That retains similarity with existing group by plans, makes rescans fairly simple, avoids very deep plans (leading to slow explains) and easily allows to avoid the sorting step if the underlying data is sorted by other means. A somewhat ugly side of this patch is having to deal with a grammar ambiguity between the new CUBE keyword and the cube extension/functions named cube (and rollup). To avoid breaking existing deployments of the cube extension it has not been renamed, neither has cube been made a reserved keyword. Instead precedence hacking is used to make GROUP BY cube(..) refer to the CUBE grouping sets feature, and not the function cube(). To actually group by a function cube(), unlikely as that might be, the function name has to be quoted. Needs a catversion bump because stored rules may change. Author: Andrew Gierth and Atri Sharma, with contributions from Andres Freund Reviewed-By: Andres Freund, Noah Misch, Tom Lane, Svenne Krap, Tomas Vondra, Erik Rijkers, Marti Raudsepp, Pavel Stehule Discussion: CAOeZVidmVRe2jU6aMk_5qkxnB7dfmPROzM7Ur8JPW5j8Y5X-Lw@mail.gmail.com
* TABLESAMPLE, SQL Standard and extensibleSimon Riggs2015-05-15
| | | | | | | | | | | | | | Add a TABLESAMPLE clause to SELECT statements that allows user to specify random BERNOULLI sampling or block level SYSTEM sampling. Implementation allows for extensible sampling functions to be written, using a standard API. Basic version follows SQLStandard exactly. Usable concrete use cases for the sampling API follow in later commits. Petr Jelinek Reviewed by Michael Paquier and Simon Riggs
* Fix ON CONFLICT bugs that manifest when used in rules.Andres Freund2015-05-13
| | | | | | | | | | | | | | Specifically the tlist and rti of the pseudo "excluded" relation weren't properly treated by expression_tree_walker, which lead to errors when excluded was referenced inside a rule because the varnos where not properly adjusted. Similar omissions in OffsetVarNodes and expression_tree_mutator had less impact, but should obviously be fixed nonetheless. A couple tests of for ON CONFLICT UPDATE into INSERT rule bearing relations have been added. In passing I updated a couple comments.
* Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE.Andres Freund2015-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The newly added ON CONFLICT clause allows to specify an alternative to raising a unique or exclusion constraint violation error when inserting. ON CONFLICT refers to constraints that can either be specified using a inference clause (by specifying the columns of a unique constraint) or by naming a unique or exclusion constraint. DO NOTHING avoids the constraint violation, without touching the pre-existing row. DO UPDATE SET ... [WHERE ...] updates the pre-existing tuple, and has access to both the tuple proposed for insertion and the existing tuple; the optional WHERE clause can be used to prevent an update from being executed. The UPDATE SET and WHERE clauses have access to the tuple proposed for insertion using the "magic" EXCLUDED alias, and to the pre-existing tuple using the table name or its alias. This feature is often referred to as upsert. This is implemented using a new infrastructure called "speculative insertion". It is an optimistic variant of regular insertion that first does a pre-check for existing tuples and then attempts an insert. If a violating tuple was inserted concurrently, the speculatively inserted tuple is deleted and a new attempt is made. If the pre-check finds a matching tuple the alternative DO NOTHING or DO UPDATE action is taken. If the insertion succeeds without detecting a conflict, the tuple is deemed inserted. To handle the possible ambiguity between the excluded alias and a table named excluded, and for convenience with long relation names, INSERT INTO now can alias its target table. Bumps catversion as stored rules change. Author: Peter Geoghegan, with significant contributions from Heikki Linnakangas and Andres Freund. Testing infrastructure by Jeff Janes. Reviewed-By: Heikki Linnakangas, Andres Freund, Robert Haas, Simon Riggs, Dean Rasheed, Stephen Frost and many others.
* Represent columns requiring insert and update privileges indentently.Andres Freund2015-05-08
| | | | | | | | | | | | | | | | | | | Previously, relation range table entries used a single Bitmapset field representing which columns required either UPDATE or INSERT privileges, despite the fact that INSERT and UPDATE privileges are separately cataloged, and may be independently held. As statements so far required either insert or update privileges but never both, that was sufficient. The required permission could be inferred from the top level statement run. The upcoming INSERT ... ON CONFLICT UPDATE feature needs to independently check for both privileges in one statement though, so that is not sufficient anymore. Bumps catversion as stored rules change. Author: Peter Geoghegan Reviewed-By: Andres Freund
* Mark views created from tables as replication identity 'nothing'Bruce Momjian2015-05-01
| | | | | | | | | pg_dump turns tables into views using a method that was not setting pg_class.relreplident properly. Patch by Marko Tiikkaja Backpatch through 9.4
* Perform RLS WITH CHECK before constraints, etcStephen Frost2015-04-24
| | | | | | | | | | | | | | | | | | | | | | | The RLS capability is built on top of the WITH CHECK OPTION system which was added for auto-updatable views, however, unlike WCOs on views (which are mandated by the SQL spec to not fire until after all other constraints and checks are done), it makes much more sense for RLS checks to happen earlier than constraint and uniqueness checks. This patch reworks the structure which holds the WCOs a bit to be explicitly either VIEW or RLS checks and the RLS-related checks are done prior to the constraint and uniqueness checks. This also allows better error reporting as we are now reporting when a violation is due to a WITH CHECK OPTION and when it's due to an RLS policy violation, which was independently noted by Craig Ringer as being confusing. The documentation is also updated to include a paragraph about when RLS WITH CHECK handling is performed, as there have been a number of questions regarding that and the documentation was previously silent on the matter. Author: Dean Rasheed, with some kabitzing and comment changes by me.
* Copy the relation name for error reporting in WCOsStephen Frost2015-04-24
| | | | | | | | | | | In get_row_security_policies(), we need to make a copy of the relation name when building the WithCheckOptions structure, since RelationGetRelationName just returns a pointer into the local Relation structure. The relation name in the WCO structure is only used for error reporting. Pointed out by Robert and Christian Ullrich, who noted that the buildfarm members with -DCLOBBER_CACHE_ALWAYS were failing.
* RLS fixes, new hooks, and new test moduleStephen Frost2015-04-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In prepend_row_security_policies(), defaultDeny was always true, so if there were any hook policies, the RLS policies on the table would just get discarded. Fixed to start off with defaultDeny as false and then properly set later if we detect that only the default deny policy exists for the internal policies. The infinite recursion detection in fireRIRrules() didn't properly manage the activeRIRs list in the case of WCOs, so it would incorrectly report infinite recusion if the same relation with RLS appeared more than once in the rtable, for example "UPDATE t ... FROM t ...". Further, the RLS expansion code in fireRIRrules() was handling RLS in the main loop through the rtable, which lead to RTEs being visited twice if they contained sublink subqueries, which prepend_row_security_policies() attempted to handle by exiting early if the RTE already had securityQuals. That doesn't work, however, since if the query involved a security barrier view on top of a table with RLS, the RTE would already have securityQuals (from the view) by the time fireRIRrules() was invoked, and so the table's RLS policies would be ignored. This is fixed in fireRIRrules() by handling RLS in a separate loop at the end, after dealing with any other sublink subqueries, thus ensuring that each RTE is only visited once for RLS expansion. The inheritance planner code didn't correctly handle non-target relations with RLS, which would get turned into subqueries during planning. Thus an update of the form "UPDATE t1 ... FROM t2 ..." where t1 has inheritance and t2 has RLS quals would fail. Fix by making sure to copy in and update the securityQuals when they exist for non-target relations. process_policies() was adding WCOs to non-target relations, which is unnecessary, and could lead to a lot of wasted time in the rewriter and the planner. Fix by only adding WCO policies when working on the result relation. Also in process_policies, we should be copying the USING policies to the WITH CHECK policies on a per-policy basis, fix by moving the copying up into the per-policy loop. Lastly, as noted by Dean, we were simply adding policies returned by the hook provided to the list of quals being AND'd, meaning that they would actually restrict records returned and there was no option to have internal policies and hook-based policies work together permissively (as all internal policies currently work). Instead, explicitly add support for both permissive and restrictive policies by having a hook for each and combining the results appropriately. To ensure this is all done correctly, add a new test module (test_rls_hooks) to test the various combinations of internal, permissive, and restrictive hook policies. Largely from Dean Rasheed (thanks!): CAEZATCVmFUfUOwwhnBTcgi6AquyjQ0-1fyKd0T3xBWJvn+xsFA@mail.gmail.com Author: Dean Rasheed, though I added the new hooks and test module.
* Change many routines to return ObjectAddress rather than OIDAlvaro Herrera2015-03-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The changed routines are mostly those that can be directly called by ProcessUtilitySlow; the intention is to make the affected object information more precise, in support for future event trigger changes. Originally it was envisioned that the OID of the affected object would be enough, and in most cases that is correct, but upon actually implementing the event trigger changes it turned out that ObjectAddress is more widely useful. Additionally, some command execution routines grew an output argument that's an object address which provides further info about the executed command. To wit: * for ALTER DOMAIN / ADD CONSTRAINT, it corresponds to the address of the new constraint * for ALTER OBJECT / SET SCHEMA, it corresponds to the address of the schema that originally contained the object. * for ALTER EXTENSION {ADD, DROP} OBJECT, it corresponds to the address of the object added to or dropped from the extension. There's no user-visible change in this commit, and no functional change either. Discussion: 20150218213255.GC6717@tamriel.snowman.net Reviewed-By: Stephen Frost, Andres Freund
* Add parse location fields to NullTest and BooleanTest structs.Tom Lane2015-02-22
| | | | | | | | We did not need a location tag on NullTest or BooleanTest before, because no error messages referred directly to their locations. That's planned to change though, so add these fields in a separate housekeeping commit. Catversion bump because stored rules may change.
* Rationalize the APIs of array element/slice access functions.Tom Lane2015-02-16
| | | | | | | | | | | | | | | | | | | | | | The four functions array_ref, array_set, array_get_slice, array_set_slice have traditionally declared their array inputs and results as being of type "ArrayType *". This is a lie, and has been since Berkeley days, because they actually also support "fixed-length array" types such as "name" and "point"; not to mention that the inputs could be toasted. These values should be declared Datum instead to avoid confusion. The current coding already risks possible misoptimization by compilers, and it'll get worse when "expanded" array representations become a valid alternative. However, there's a fair amount of code using array_ref and array_set with arrays that *are* known to be ArrayType structures, and there might be more such places in third-party code. Rather than cluttering those call sites with PointerGetDatum/DatumGetArrayTypeP cruft, what I did was to rename the existing functions to array_get_element/array_set_element, fix their signatures, then reincarnate array_ref/array_set as backwards compatibility wrappers. array_get_slice/array_set_slice have no such constituency in the core code, and probably not in third-party code either, so I just changed their APIs.
* Fix column-privilege leak in error-message pathsStephen Frost2015-01-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | While building error messages to return to the user, BuildIndexValueDescription, ExecBuildSlotValueDescription and ri_ReportViolation would happily include the entire key or entire row in the result returned to the user, even if the user didn't have access to view all of the columns being included. Instead, include only those columns which the user is providing or which the user has select rights on. If the user does not have any rights to view the table or any of the columns involved then no detail is provided and a NULL value is returned from BuildIndexValueDescription and ExecBuildSlotValueDescription. Note that, for key cases, the user must have access to all of the columns for the key to be shown; a partial key will not be returned. Further, in master only, do not return any data for cases where row security is enabled on the relation and row security should be applied for the user. This required a bit of refactoring and moving of things around related to RLS- note the addition of utils/misc/rls.c. Back-patch all the way, as column-level privileges are now in all supported versions. This has been assigned CVE-2014-8161, but since the issue and the patch have already been publicized on pgsql-hackers, there's no point in trying to hide this commit.
* Clean up some mess in row-security patches.Tom Lane2015-01-24
| | | | | | | | | | | | | | | | | | | | | | | | | | Fix unsafe coding around PG_TRY in RelationBuildRowSecurity: can't change a variable inside PG_TRY and then use it in PG_CATCH without marking it "volatile". In this case though it seems saner to avoid that by doing a single assignment before entering the TRY block. I started out just intending to fix that, but the more I looked at the row-security code the more distressed I got. This patch also fixes incorrect construction of the RowSecurityPolicy cache entries (there was not sufficient care taken to copy pass-by-ref data into the cache memory context) and a whole bunch of sloppiness around the definition and use of pg_policy.polcmd. You can't use nulls in that column because initdb will mark it NOT NULL --- and I see no particular reason why a null entry would be a good idea anyway, so changing initdb's behavior is not the right answer. The internal value of '\0' wouldn't be suitable in a "char" column either, so after a bit of thought I settled on using '*' to represent ALL. Chasing those changes down also revealed that somebody wasn't paying attention to what the underlying values of ACL_UPDATE_CHR etc really were, and there was a great deal of lackadaiscalness in the catalogs.sgml documentation for pg_policy and pg_policies too. This doesn't pretend to be a complete code review for the row-security stuff, it just fixes the things that were in my face while dealing with the bugs in RelationBuildRowSecurity.
* Update copyright for 2015Bruce Momjian2015-01-06
| | | | Backpatch certain files through 9.0
* Revert "Use a bitmask to represent role attributes"Alvaro Herrera2014-12-23
| | | | | | | | | This reverts commit 1826987a46d079458007b7b6bbcbbd852353adbb. The overall design was deemed unacceptable, in discussion following the previous commit message; we might find some parts of it still salvageable, but I don't want to be on the hook for fixing it, so let's wait until we have a new patch.
* Use a bitmask to represent role attributesAlvaro Herrera2014-12-23
| | | | | | | | | | | | | The previous representation using a boolean column for each attribute would not scale as well as we want to add further attributes. Extra auxilliary functions are added to go along with this change, to make up for the lost convenience of access of the old representation. Catalog version bumped due to change in catalogs and the new functions. Author: Adam Brightwell, minor tweaks by Álvaro Reviewed by: Stephen Frost, Andres Freund, Álvaro Herrera
* Add bms_next_member(), and use it where appropriate.Tom Lane2014-11-28
| | | | | | | | | | | | This patch adds a way of iterating through the members of a bitmapset nondestructively, unlike the old way with bms_first_member(). While bms_next_member() is very slightly slower than bms_first_member() (at least for typical-size bitmapsets), eliminating the need to palloc and pfree a temporary copy of the target bitmapset is a significant win. So this method should be preferred in all cases where a temporary copy would be necessary. Tom Lane, with suggestions from Dean Rasheed and David Rowley
* Rename pg_rowsecurity -> pg_policy and other fixesStephen Frost2014-11-27
| | | | | | | | | | | | | | | | | | | | | | | | | As pointed out by Robert, we should really have named pg_rowsecurity pg_policy, as the objects stored in that catalog are policies. This patch fixes that and updates the column names to start with 'pol' to match the new catalog name. The security consideration for COPY with row level security, also pointed out by Robert, has also been addressed by remembering and re-checking the OID of the relation initially referenced during COPY processing, to make sure it hasn't changed under us by the time we finish planning out the query which has been built. Robert and Alvaro also commented on missing OCLASS and OBJECT entries for POLICY (formerly ROWSECURITY or POLICY, depending) in various places. This patch fixes that too, which also happens to add the ability to COMMENT on policies. In passing, attempt to improve the consistency of messages, comments, and documentation as well. This removes various incarnations of 'row-security', 'row-level security', 'Row-security', etc, in favor of 'policy', 'row level security' or 'row_security' as appropriate. Happy Thanksgiving!
* Clean up includes from RLS patchStephen Frost2014-11-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | The initial patch for RLS mistakenly included headers associated with the executor and planner bits in rewrite/rowsecurity.h. Per policy and general good sense, executor headers should not be included in planner headers or vice versa. The include of execnodes.h was a mistaken holdover from previous versions, while the include of relation.h was used for Relation's definition, which should have been coming from utils/relcache.h. This patch cleans these issues up, adds comments to the RowSecurityPolicy struct and the RowSecurityConfigType enum, and changes Relation->rsdesc to Relation->rd_rsdesc to follow Relation field naming convention. Additionally, utils/rel.h was including rewrite/rowsecurity.h, which wasn't a great idea since that was pulling in things not really needed in utils/rel.h (which gets included in quite a few places). Instead, use 'struct RowSecurityDesc' for the rd_rsdesc field and add comments explaining why. Lastly, add an include into access/nbtree/nbtsort.c for utils/sortsupport.h, which was evidently missed due to the above mess. Pointed out by Tom in 16970.1415838651@sss.pgh.pa.us; note that the concerns regarding a similar situation in the custom-path commit still need to be addressed.
* Implement SKIP LOCKED for row-level locksAlvaro Herrera2014-10-07
| | | | | | | | | | | | | | | | | | This clause changes the behavior of SELECT locking clauses in the presence of locked rows: instead of causing a process to block waiting for the locks held by other processes (or raise an error, with NOWAIT), SKIP LOCKED makes the new reader skip over such rows. While this is not appropriate behavior for general purposes, there are some cases in which it is useful, such as queue-like tables. Catalog version bumped because this patch changes the representation of stored rules. Reviewed by Craig Ringer (based on a previous attempt at an implementation by Simon Riggs, who also provided input on the syntax used in the current patch), David Rowley, and Álvaro Herrera. Author: Thomas Munro
* Fix typos in comments.Robert Haas2014-10-03
| | | | Etsuro Fujita
* Code review for row security.Stephen Frost2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Buildfarm member tick identified an issue where the policies in the relcache for a relation were were being replaced underneath a running query, leading to segfaults while processing the policies to be added to a query. Similar to how TupleDesc RuleLocks are handled, add in a equalRSDesc() function to check if the policies have actually changed and, if not, swap back the rsdesc field (using the original instead of the temporairly built one; the whole structure is swapped and then specific fields swapped back). This now passes a CLOBBER_CACHE_ALWAYS for me and should resolve the buildfarm error. In addition to addressing this, add a new chapter in Data Definition under Privileges which explains row security and provides examples of its usage, change \d to always list policies (even if row security is disabled- but note that it is disabled, or enabled with no policies), rework check_role_for_policy (it really didn't need the entire policy, but it did need to be using has_privs_of_role()), and change the field in pg_class to relrowsecurity from relhasrowsecurity, based on Heikki's suggestion. Also from Heikki, only issue SET ROW_SECURITY in pg_restore when talking to a 9.5+ server, list Bypass RLS in \du, and document --enable-row-security options for pg_dump and pg_restore. Lastly, fix a number of minor whitespace and typo issues from Heikki, Dimitri, add a missing #include, per Peter E, fix a few minor variable-assigned-but-not-used and resource leak issues from Coverity and add tab completion for role attribute bypassrls as well.
* Row-Level Security Policies (RLS)Stephen Frost2014-09-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Building on the updatable security-barrier views work, add the ability to define policies on tables to limit the set of rows which are returned from a query and which are allowed to be added to a table. Expressions defined by the policy for filtering are added to the security barrier quals of the query, while expressions defined to check records being added to a table are added to the with-check options of the query. New top-level commands are CREATE/ALTER/DROP POLICY and are controlled by the table owner. Row Security is able to be enabled and disabled by the owner on a per-table basis using ALTER TABLE .. ENABLE/DISABLE ROW SECURITY. Per discussion, ROW SECURITY is disabled on tables by default and must be enabled for policies on the table to be used. If no policies exist on a table with ROW SECURITY enabled, a default-deny policy is used and no records will be visible. By default, row security is applied at all times except for the table owner and the superuser. A new GUC, row_security, is added which can be set to ON, OFF, or FORCE. When set to FORCE, row security will be applied even for the table owner and superusers. When set to OFF, row security will be disabled when allowed and an error will be thrown if the user does not have rights to bypass row security. Per discussion, pg_dump sets row_security = OFF by default to ensure that exports and backups will have all data in the table or will error if there are insufficient privileges to bypass row security. A new option has been added to pg_dump, --enable-row-security, to ask pg_dump to export with row security enabled. A new role capability, BYPASSRLS, which can only be set by the superuser, is added to allow other users to be able to bypass row security using row_security = OFF. Many thanks to the various individuals who have helped with the design, particularly Robert Haas for his feedback. Authors include Craig Ringer, KaiGai Kohei, Adam Brightwell, Dean Rasheed, with additional changes and rework by me. Reviewers have included all of the above, Greg Smith, Jeff McCormick, and Robert Haas.
* Assorted message improvementsPeter Eisentraut2014-08-29
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* Add some errdetail to checkRuleResultList().Tom Lane2014-07-02
| | | | | | | | | | | | | | | | | This function wasn't originally thought to be really user-facing, because converting a table to a view isn't something we expect people to do manually. So not all that much effort was spent on the error messages; in particular, while the code will complain that you got the column types wrong it won't say exactly what they are. But since we repurposed the code to also check compatibility of rule RETURNING lists, it's definitely user-facing. It now seems worthwhile to add errdetail messages showing exactly what the conflict is when there's a mismatch of column names or types. This is prompted by bug #10836 from Matthias Raffelsieper, which might have been forestalled if the error message had reported the wrong column type as being "record". Back-patch to 9.4, but not into older branches where the set of translatable error strings is supposed to be stable.
* Implement UPDATE tab SET (col1,col2,...) = (SELECT ...), ...Tom Lane2014-06-18
| | | | | | | | | | | | | | | | This SQL-standard feature allows a sub-SELECT yielding multiple columns (but only one row) to be used to compute the new values of several columns to be updated. While the same results can be had with an independent sub-SELECT per column, such a workaround can require a great deal of duplicated computation. The standard actually says that the source for a multi-column assignment could be any row-valued expression. The implementation used here is tightly tied to our existing sub-SELECT support and can't handle other cases; the Bison grammar would have some issues with them too. However, I don't feel too bad about this since other cases can be converted into sub-SELECTs. For instance, "SET (a,b,c) = row_valued_function(x)" could be written "SET (a,b,c) = (SELECT * FROM row_valued_function(x))".
* pgindent run for 9.4Bruce Momjian2014-05-06
| | | | | This includes removing tabs after periods in C comments, which was applied to back branches, so this change should not effect backpatching.
* Make security barrier views automatically updatableStephen Frost2014-04-12
| | | | | | | | | | | | | | | | | Views which are marked as security_barrier must have their quals applied before any user-defined quals are called, to prevent user-defined functions from being able to see rows which the security barrier view is intended to prevent them from seeing. Remove the restriction on security barrier views being automatically updatable by adding a new securityQuals list to the RTE structure which keeps track of the quals from security barrier views at each level, independently of the user-supplied quals. When RTEs are later discovered which have securityQuals populated, they are turned into subquery RTEs which are marked as security_barrier to prevent any user-supplied quals being pushed down (modulo LEAKPROOF quals). Dean Rasheed, reviewed by Craig Ringer, Simon Riggs, KaiGai Kohei
* Offer triggers on foreign tables.Noah Misch2014-03-23
| | | | | | | | | | | | | | | | | This covers all the SQL-standard trigger types supported for regular tables; it does not cover constraint triggers. The approach for acquiring the old row mirrors that for view INSTEAD OF triggers. For AFTER ROW triggers, we spool the foreign tuples to a tuplestore. This changes the FDW API contract; when deciding which columns to populate in the slot returned from data modification callbacks, writable FDWs will need to check for AFTER ROW triggers in addition to checking for a RETURNING clause. In support of the feature addition, refactor the TriggerFlags bits and the assembly of old tuples in ModifyTable. Ronan Dunklau, reviewed by KaiGai Kohei; some additional hacking by me.
* Fix typos in comments.Fujii Masao2014-03-17
| | | | Thom Brown