diff --git a/contrib/citext/Makefile b/contrib/citext/Makefile index a7de52928d7..cae93d9e49d 100644 --- a/contrib/citext/Makefile +++ b/contrib/citext/Makefile @@ -11,7 +11,7 @@ DATA = citext--1.4.sql \ citext--1.0--1.1.sql PGFILEDESC = "citext - case-insensitive character string data type" -REGRESS = citext +REGRESS = create_index_acl citext ifdef USE_PGXS PG_CONFIG = pg_config diff --git a/contrib/citext/expected/create_index_acl.out b/contrib/citext/expected/create_index_acl.out new file mode 100644 index 00000000000..f35f60b421d --- /dev/null +++ b/contrib/citext/expected/create_index_acl.out @@ -0,0 +1,78 @@ +-- Each DefineIndex() ACL check uses either the original userid or the table +-- owner userid; see its header comment. Here, confirm that DefineIndex() +-- uses its original userid where necessary. The test works by creating +-- indexes that refer to as many sorts of objects as possible, with the table +-- owner having as few applicable privileges as possible. (The privileges.sql +-- regress_sro_user tests look for the opposite defect; they confirm that +-- DefineIndex() uses the table owner userid where necessary.) +-- Don't override tablespaces; this version lacks allow_in_place_tablespaces. +BEGIN; +CREATE ROLE regress_minimal; +CREATE SCHEMA s; +CREATE EXTENSION citext SCHEMA s; +-- Revoke all conceivably-relevant ACLs within the extension. The system +-- doesn't check all these ACLs, but this will provide some coverage if that +-- ever changes. +REVOKE ALL ON TYPE s.citext FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_lt FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_le FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_eq FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_ge FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_gt FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_cmp FROM PUBLIC; +-- Functions sufficient for making an index column that has the side effect of +-- changing search_path at expression planning time. +CREATE FUNCTION public.setter() RETURNS bool VOLATILE + LANGUAGE SQL AS $$SET search_path = s; SELECT true$$; +CREATE FUNCTION s.const() RETURNS bool IMMUTABLE + LANGUAGE SQL AS $$SELECT public.setter()$$; +CREATE FUNCTION s.index_this_expr(s.citext, bool) RETURNS s.citext IMMUTABLE + LANGUAGE SQL AS $$SELECT $1$$; +REVOKE ALL ON FUNCTION public.setter FROM PUBLIC; +REVOKE ALL ON FUNCTION s.const FROM PUBLIC; +REVOKE ALL ON FUNCTION s.index_this_expr FROM PUBLIC; +-- Even for an empty table, expression planning calls s.const & public.setter. +GRANT EXECUTE ON FUNCTION public.setter TO regress_minimal; +GRANT EXECUTE ON FUNCTION s.const TO regress_minimal; +-- Function for index predicate. +CREATE FUNCTION s.index_row_if(s.citext) RETURNS bool IMMUTABLE + LANGUAGE SQL AS $$SELECT $1 IS NOT NULL$$; +REVOKE ALL ON FUNCTION s.index_row_if FROM PUBLIC; +-- Even for an empty table, CREATE INDEX checks ii_Predicate permissions. +GRANT EXECUTE ON FUNCTION s.index_row_if TO regress_minimal; +-- Non-extension, non-function objects. +CREATE COLLATION s.coll (LOCALE="C"); +CREATE TABLE s.x (y s.citext); +ALTER TABLE s.x OWNER TO regress_minimal; +-- Empty-table DefineIndex() +CREATE UNIQUE INDEX u0rows ON s.x USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll s.citext_pattern_ops) + WHERE s.index_row_if(y); +ALTER TABLE s.x ADD CONSTRAINT e0rows EXCLUDE USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll WITH s.=) + WHERE (s.index_row_if(y)); +-- Make the table nonempty. +INSERT INTO s.x VALUES ('foo'), ('bar'); +-- If the INSERT runs the planner on index expressions, a search_path change +-- survives. As of 2022-06, the INSERT reuses a cached plan. It does so even +-- under debug_discard_caches, since each index is new-in-transaction. If +-- future work changes a cache lifecycle, this RESET may become necessary. +RESET search_path; +-- For a nonempty table, owner needs permissions throughout ii_Expressions. +GRANT EXECUTE ON FUNCTION s.index_this_expr TO regress_minimal; +CREATE UNIQUE INDEX u2rows ON s.x USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll s.citext_pattern_ops) + WHERE s.index_row_if(y); +ALTER TABLE s.x ADD CONSTRAINT e2rows EXCLUDE USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll WITH s.=) + WHERE (s.index_row_if(y)); +-- Shall not find s.coll via search_path, despite the s.const->public.setter +-- call having set search_path=s during expression planning. Suppress the +-- message itself, which depends on the database encoding. +\set VERBOSITY sqlstate +ALTER TABLE s.x ADD CONSTRAINT underqualified EXCLUDE USING btree + ((s.index_this_expr(y, s.const())) COLLATE coll WITH s.=) + WHERE (s.index_row_if(y)); +ERROR: 42704 +\set VERBOSITY default +ROLLBACK; diff --git a/contrib/citext/sql/create_index_acl.sql b/contrib/citext/sql/create_index_acl.sql new file mode 100644 index 00000000000..a5f4e6b30a8 --- /dev/null +++ b/contrib/citext/sql/create_index_acl.sql @@ -0,0 +1,79 @@ +-- Each DefineIndex() ACL check uses either the original userid or the table +-- owner userid; see its header comment. Here, confirm that DefineIndex() +-- uses its original userid where necessary. The test works by creating +-- indexes that refer to as many sorts of objects as possible, with the table +-- owner having as few applicable privileges as possible. (The privileges.sql +-- regress_sro_user tests look for the opposite defect; they confirm that +-- DefineIndex() uses the table owner userid where necessary.) + +-- Don't override tablespaces; this version lacks allow_in_place_tablespaces. + +BEGIN; +CREATE ROLE regress_minimal; +CREATE SCHEMA s; +CREATE EXTENSION citext SCHEMA s; +-- Revoke all conceivably-relevant ACLs within the extension. The system +-- doesn't check all these ACLs, but this will provide some coverage if that +-- ever changes. +REVOKE ALL ON TYPE s.citext FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_lt FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_le FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_eq FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_ge FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_gt FROM PUBLIC; +REVOKE ALL ON FUNCTION s.citext_pattern_cmp FROM PUBLIC; +-- Functions sufficient for making an index column that has the side effect of +-- changing search_path at expression planning time. +CREATE FUNCTION public.setter() RETURNS bool VOLATILE + LANGUAGE SQL AS $$SET search_path = s; SELECT true$$; +CREATE FUNCTION s.const() RETURNS bool IMMUTABLE + LANGUAGE SQL AS $$SELECT public.setter()$$; +CREATE FUNCTION s.index_this_expr(s.citext, bool) RETURNS s.citext IMMUTABLE + LANGUAGE SQL AS $$SELECT $1$$; +REVOKE ALL ON FUNCTION public.setter FROM PUBLIC; +REVOKE ALL ON FUNCTION s.const FROM PUBLIC; +REVOKE ALL ON FUNCTION s.index_this_expr FROM PUBLIC; +-- Even for an empty table, expression planning calls s.const & public.setter. +GRANT EXECUTE ON FUNCTION public.setter TO regress_minimal; +GRANT EXECUTE ON FUNCTION s.const TO regress_minimal; +-- Function for index predicate. +CREATE FUNCTION s.index_row_if(s.citext) RETURNS bool IMMUTABLE + LANGUAGE SQL AS $$SELECT $1 IS NOT NULL$$; +REVOKE ALL ON FUNCTION s.index_row_if FROM PUBLIC; +-- Even for an empty table, CREATE INDEX checks ii_Predicate permissions. +GRANT EXECUTE ON FUNCTION s.index_row_if TO regress_minimal; +-- Non-extension, non-function objects. +CREATE COLLATION s.coll (LOCALE="C"); +CREATE TABLE s.x (y s.citext); +ALTER TABLE s.x OWNER TO regress_minimal; +-- Empty-table DefineIndex() +CREATE UNIQUE INDEX u0rows ON s.x USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll s.citext_pattern_ops) + WHERE s.index_row_if(y); +ALTER TABLE s.x ADD CONSTRAINT e0rows EXCLUDE USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll WITH s.=) + WHERE (s.index_row_if(y)); +-- Make the table nonempty. +INSERT INTO s.x VALUES ('foo'), ('bar'); +-- If the INSERT runs the planner on index expressions, a search_path change +-- survives. As of 2022-06, the INSERT reuses a cached plan. It does so even +-- under debug_discard_caches, since each index is new-in-transaction. If +-- future work changes a cache lifecycle, this RESET may become necessary. +RESET search_path; +-- For a nonempty table, owner needs permissions throughout ii_Expressions. +GRANT EXECUTE ON FUNCTION s.index_this_expr TO regress_minimal; +CREATE UNIQUE INDEX u2rows ON s.x USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll s.citext_pattern_ops) + WHERE s.index_row_if(y); +ALTER TABLE s.x ADD CONSTRAINT e2rows EXCLUDE USING btree + ((s.index_this_expr(y, s.const())) COLLATE s.coll WITH s.=) + WHERE (s.index_row_if(y)); +-- Shall not find s.coll via search_path, despite the s.const->public.setter +-- call having set search_path=s during expression planning. Suppress the +-- message itself, which depends on the database encoding. +\set VERBOSITY sqlstate +ALTER TABLE s.x ADD CONSTRAINT underqualified EXCLUDE USING btree + ((s.index_this_expr(y, s.const())) COLLATE coll WITH s.=) + WHERE (s.index_row_if(y)); +\set VERBOSITY default +ROLLBACK; diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c index c3627bb0b6c..8853f00a788 100644 --- a/src/backend/commands/indexcmds.c +++ b/src/backend/commands/indexcmds.c @@ -79,7 +79,10 @@ static void ComputeIndexAttrs(IndexInfo *indexInfo, Oid relId, const char *accessMethodName, Oid accessMethodId, bool amcanorder, - bool isconstraint); + bool isconstraint, + Oid ddl_userid, + int ddl_sec_context, + int *ddl_save_nestlevel); static char *ChooseIndexName(const char *tabname, Oid namespaceId, List *colnames, List *exclusionOpNames, bool primary, bool isconstraint); @@ -198,9 +201,8 @@ CheckIndexCompatible(Oid oldId, * Compute the operator classes, collations, and exclusion operators for * the new index, so we can test whether it's compatible with the existing * one. Note that ComputeIndexAttrs might fail here, but that's OK: - * DefineIndex would have called this function with the same arguments - * later on, and it would have failed then anyway. Our attributeList - * contains only key attributes, thus we're filling ii_NumIndexAttrs and + * DefineIndex would have failed later. Our attributeList contains only + * key attributes, thus we're filling ii_NumIndexAttrs and * ii_NumIndexKeyAttrs with same value. */ indexInfo = makeIndexInfo(numberOfAttributes, numberOfAttributes, @@ -214,7 +216,7 @@ CheckIndexCompatible(Oid oldId, coloptions, attributeList, exclusionOpNames, relationId, accessMethodName, accessMethodId, - amcanorder, isconstraint); + amcanorder, isconstraint, InvalidOid, 0, NULL); /* Get the soon-obsolete pg_index tuple. */ @@ -455,6 +457,19 @@ WaitForOlderSnapshots(TransactionId limitXmin, bool progress) * DefineIndex * Creates a new index. * + * This function manages the current userid according to the needs of pg_dump. + * Recreating old-database catalog entries in new-database is fine, regardless + * of which users would have permission to recreate those entries now. That's + * just preservation of state. Running opaque expressions, like calling a + * function named in a catalog entry or evaluating a pg_node_tree in a catalog + * entry, as anyone other than the object owner, is not fine. To adhere to + * those principles and to remain fail-safe, use the table owner userid for + * most ACL checks. Use the original userid for ACL checks reached without + * traversing opaque expressions. (pg_dump can predict such ACL checks from + * catalogs.) Overall, this is a mess. Future DDL development should + * consider offering one DDL command for catalog setup and a separate DDL + * command for steps that run opaque expressions. + * * 'relationId': the OID of the heap relation on which the index is to be * created * 'stmt': IndexStmt describing the properties of the new index. @@ -871,7 +886,8 @@ DefineIndex(Oid relationId, coloptions, allIndexParams, stmt->excludeOpNames, relationId, accessMethodName, accessMethodId, - amcanorder, stmt->isconstraint); + amcanorder, stmt->isconstraint, root_save_userid, + root_save_sec_context, &root_save_nestlevel); /* * Extra checks when creating a PRIMARY KEY index. @@ -1147,11 +1163,8 @@ DefineIndex(Oid relationId, /* * Roll back any GUC changes executed by index functions, and keep - * subsequent changes local to this command. It's barely possible that - * some index function changed a behavior-affecting GUC, e.g. xmloption, - * that affects subsequent steps. This improves bug-compatibility with - * older PostgreSQL versions. They did the AtEOXact_GUC() here for the - * purpose of clearing the above default_tablespace change. + * subsequent changes local to this command. This is essential if some + * index function changed a behavior-affecting GUC, e.g. search_path. */ AtEOXact_GUC(false, root_save_nestlevel); root_save_nestlevel = NewGUCNestLevel(); @@ -1686,6 +1699,10 @@ CheckPredicate(Expr *predicate) * Compute per-index-column information, including indexed column numbers * or index expressions, opclasses and their options. Note, all output vectors * should be allocated for all columns, including "including" ones. + * + * If the caller switched to the table owner, ddl_userid is the role for ACL + * checks reached without traversing opaque expressions. Otherwise, it's + * InvalidOid, and other ddl_* arguments are undefined. */ static void ComputeIndexAttrs(IndexInfo *indexInfo, @@ -1699,12 +1716,17 @@ ComputeIndexAttrs(IndexInfo *indexInfo, const char *accessMethodName, Oid accessMethodId, bool amcanorder, - bool isconstraint) + bool isconstraint, + Oid ddl_userid, + int ddl_sec_context, + int *ddl_save_nestlevel) { ListCell *nextExclOp; ListCell *lc; int attn; int nkeycols = indexInfo->ii_NumIndexKeyAttrs; + Oid save_userid; + int save_sec_context; /* Allocate space for exclusion operator info, if needed */ if (exclusionOpNames) @@ -1718,6 +1740,9 @@ ComputeIndexAttrs(IndexInfo *indexInfo, else nextExclOp = NULL; + if (OidIsValid(ddl_userid)) + GetUserIdAndSecContext(&save_userid, &save_sec_context); + /* * process attributeList */ @@ -1848,10 +1873,24 @@ ComputeIndexAttrs(IndexInfo *indexInfo, } /* - * Apply collation override if any + * Apply collation override if any. Use of ddl_userid is necessary + * due to ACL checks therein, and it's safe because collations don't + * contain opaque expressions (or non-opaque expressions). */ if (attribute->collation) + { + if (OidIsValid(ddl_userid)) + { + AtEOXact_GUC(false, *ddl_save_nestlevel); + SetUserIdAndSecContext(ddl_userid, ddl_sec_context); + } attcollation = get_collation_oid(attribute->collation, false); + if (OidIsValid(ddl_userid)) + { + SetUserIdAndSecContext(save_userid, save_sec_context); + *ddl_save_nestlevel = NewGUCNestLevel(); + } + } /* * Check we have a collation iff it's a collatable type. The only @@ -1879,12 +1918,25 @@ ComputeIndexAttrs(IndexInfo *indexInfo, collationOidP[attn] = attcollation; /* - * Identify the opclass to use. + * Identify the opclass to use. Use of ddl_userid is necessary due to + * ACL checks therein. This is safe despite opclasses containing + * opaque expressions (specifically, functions), because only + * superusers can define opclasses. */ + if (OidIsValid(ddl_userid)) + { + AtEOXact_GUC(false, *ddl_save_nestlevel); + SetUserIdAndSecContext(ddl_userid, ddl_sec_context); + } classOidP[attn] = ResolveOpClass(attribute->opclass, atttype, accessMethodName, accessMethodId); + if (OidIsValid(ddl_userid)) + { + SetUserIdAndSecContext(save_userid, save_sec_context); + *ddl_save_nestlevel = NewGUCNestLevel(); + } /* * Identify the exclusion operator, if any. @@ -1898,9 +1950,23 @@ ComputeIndexAttrs(IndexInfo *indexInfo, /* * Find the operator --- it must accept the column datatype - * without runtime coercion (but binary compatibility is OK) + * without runtime coercion (but binary compatibility is OK). + * Operators contain opaque expressions (specifically, functions). + * compatible_oper_opid() boils down to oper() and + * IsBinaryCoercible(). PostgreSQL would have security problems + * elsewhere if oper() started calling opaque expressions. */ + if (OidIsValid(ddl_userid)) + { + AtEOXact_GUC(false, *ddl_save_nestlevel); + SetUserIdAndSecContext(ddl_userid, ddl_sec_context); + } opid = compatible_oper_opid(opname, atttype, atttype, false); + if (OidIsValid(ddl_userid)) + { + SetUserIdAndSecContext(save_userid, save_sec_context); + *ddl_save_nestlevel = NewGUCNestLevel(); + } /* * Only allow commutative operators to be used in exclusion