19 Commits (22eaf35c1d247407b7cf1fffb310a26cd9b9ceb1)

Author	SHA1	Message	Date
Stephen Frost	22eaf35c1d	RLS refactoring ... 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.	10 years ago
Stephen Frost	dee0200f02	RLS: Keep deny policy when only restrictive exist ... 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.	10 years ago
Joe Conway	1e15b21229	Use appropriate command type when retrieving relation's policies. ... 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.	10 years ago
Joe Conway	7b4bfc87d5	Plug RLS related information leak in pg_stats view. ... 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.	10 years ago
Tom Lane	2aa0476dc3	Manual cleanup of pgindent results. ... 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.)	10 years ago
Bruce Momjian	807b9e0dff	pgindent run for 9.5	10 years ago
Andres Freund	168d5805e4	Add support for INSERT ... ON CONFLICT DO NOTHING/UPDATE. ... 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.	11 years ago
Stephen Frost	e89bd02f58	Perform RLS WITH CHECK before constraints, etc ... 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.	11 years ago
Stephen Frost	cb087ec03b	Copy the relation name for error reporting in WCOs ... 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.	11 years ago
Stephen Frost	0bf22e0c8b	RLS fixes, new hooks, and new test module ... 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.	11 years ago
Stephen Frost	804b6b6db4	Fix column-privilege leak in error-message paths ... 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.	11 years ago
Tom Lane	fd496129d1	Clean up some mess in row-security patches. ... 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.	11 years ago
Bruce Momjian	4baaf863ec	Update copyright for 2015 ... Backpatch certain files through 9.0	11 years ago
Alvaro Herrera	a609d96778	Revert "Use a bitmask to represent role attributes" ... This reverts commit 1826987a46. 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.	11 years ago
Alvaro Herrera	1826987a46	Use a bitmask to represent role attributes ... 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	11 years ago
Stephen Frost	143b39c185	Rename pg_rowsecurity -> pg_policy and other fixes ... 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!	11 years ago
Stephen Frost	80eacaa3cd	Clean up includes from RLS patch ... 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.	11 years ago
Stephen Frost	6550b901fe	Code review for row security. ... 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.	11 years ago
Stephen Frost	491c029dbc	Row-Level Security Policies (RLS) ... 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.	11 years ago