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/* -------------------------------------------------------------------------
*
* contrib/sepgsql/database.c
*
* Routines corresponding to database objects
*
* Copyright (c) 2010-2012, PostgreSQL Global Development Group
*
* -------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/genam.h"
#include "access/heapam.h"
#include "access/sysattr.h"
#include "catalog/dependency.h"
#include "catalog/pg_database.h"
#include "catalog/indexing.h"
#include "commands/dbcommands.h"
#include "commands/seclabel.h"
#include "utils/fmgroids.h"
#include "utils/tqual.h"
#include "sepgsql.h"
/*
* sepgsql_database_post_create
*
* This routine assigns a default security label on a newly defined
* database, and check permission needed for its creation.
*/
void
sepgsql_database_post_create(Oid databaseId, const char *dtemplate)
{
Relation rel;
ScanKeyData skey;
SysScanDesc sscan;
HeapTuple tuple;
char *tcontext;
char *ncontext;
char audit_name[NAMEDATALEN + 20];
ObjectAddress object;
Form_pg_database datForm;
/*
* Oid of the source database is not saved in pg_database catalog,
* so we collect its identifier using contextual information.
* If NULL, its default is "template1" according to createdb().
*/
if (!dtemplate)
dtemplate = "template1";
object.classId = DatabaseRelationId;
object.objectId = get_database_oid(dtemplate, false);
object.objectSubId = 0;
tcontext = sepgsql_get_label(object.classId,
object.objectId,
object.objectSubId);
/*
* check db_database:{getattr} permission
*/
snprintf(audit_name, sizeof(audit_name), "database %s", dtemplate);
sepgsql_avc_check_perms_label(tcontext,
SEPG_CLASS_DB_DATABASE,
SEPG_DB_DATABASE__GETATTR,
audit_name,
true);
/*
* Compute a default security label of the newly created database
* based on a pair of security label of client and source database.
*
* XXX - uncoming version of libselinux supports to take object
* name to handle special treatment on default security label.
*/
rel = heap_open(DatabaseRelationId, AccessShareLock);
ScanKeyInit(&skey,
ObjectIdAttributeNumber,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(databaseId));
sscan = systable_beginscan(rel, DatabaseOidIndexId, true,
SnapshotSelf, 1, &skey);
tuple = systable_getnext(sscan);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "catalog lookup failed for database %u", databaseId);
datForm = (Form_pg_database) GETSTRUCT(tuple);
ncontext = sepgsql_compute_create(sepgsql_get_client_label(),
tcontext,
SEPG_CLASS_DB_DATABASE);
/*
* check db_database:{create} permission
*/
snprintf(audit_name, sizeof(audit_name),
"database %s", NameStr(datForm->datname));
sepgsql_avc_check_perms_label(ncontext,
SEPG_CLASS_DB_DATABASE,
SEPG_DB_DATABASE__CREATE,
audit_name,
true);
systable_endscan(sscan);
heap_close(rel, AccessShareLock);
/*
* Assign the default security label on the new database
*/
object.classId = DatabaseRelationId;
object.objectId = databaseId;
object.objectSubId = 0;
SetSecurityLabel(&object, SEPGSQL_LABEL_TAG, ncontext);
pfree(ncontext);
pfree(tcontext);
}
/*
* sepgsql_database_relabel
*
* It checks privileges to relabel the supplied database with the `seclabel'
*/
void
sepgsql_database_relabel(Oid databaseId, const char *seclabel)
{
ObjectAddress object;
char *audit_name;
object.classId = DatabaseRelationId;
object.objectId = databaseId;
object.objectSubId = 0;
audit_name = getObjectDescription(&object);
/*
* check db_database:{setattr relabelfrom} permission
*/
sepgsql_avc_check_perms(&object,
SEPG_CLASS_DB_DATABASE,
SEPG_DB_DATABASE__SETATTR |
SEPG_DB_DATABASE__RELABELFROM,
audit_name,
true);
/*
* check db_database:{relabelto} permission
*/
sepgsql_avc_check_perms_label(seclabel,
SEPG_CLASS_DB_DATABASE,
SEPG_DB_DATABASE__RELABELTO,
audit_name,
true);
pfree(audit_name);
}
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