/*
* Copyright 1999-2011 Alibaba Group Holding Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.druid.wall.spi;
import com.alibaba.druid.sql.SQLUtils;
import com.alibaba.druid.sql.ast.SQLName;
import com.alibaba.druid.sql.ast.SQLObject;
import com.alibaba.druid.sql.ast.expr.SQLBinaryOpExpr;
import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
import com.alibaba.druid.sql.ast.expr.SQLInListExpr;
import com.alibaba.druid.sql.ast.expr.SQLMethodInvokeExpr;
import com.alibaba.druid.sql.ast.expr.SQLPropertyExpr;
import com.alibaba.druid.sql.ast.expr.SQLVariantRefExpr;
import com.alibaba.druid.sql.ast.statement.SQLAlterTableStatement;
import com.alibaba.druid.sql.ast.statement.SQLCallStatement;
import com.alibaba.druid.sql.ast.statement.SQLCreateTableStatement;
import com.alibaba.druid.sql.ast.statement.SQLCreateTriggerStatement;
import com.alibaba.druid.sql.ast.statement.SQLDeleteStatement;
import com.alibaba.druid.sql.ast.statement.SQLDropTableStatement;
import com.alibaba.druid.sql.ast.statement.SQLExprTableSource;
import com.alibaba.druid.sql.ast.statement.SQLInsertStatement;
import com.alibaba.druid.sql.ast.statement.SQLSelectGroupByClause;
import com.alibaba.druid.sql.ast.statement.SQLSelectItem;
import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock;
import com.alibaba.druid.sql.ast.statement.SQLSelectStatement;
import com.alibaba.druid.sql.ast.statement.SQLSetStatement;
import com.alibaba.druid.sql.ast.statement.SQLUnionQuery;
import com.alibaba.druid.sql.ast.statement.SQLUpdateStatement;
import com.alibaba.druid.sql.dialect.sqlserver.ast.SQLServerSelectQueryBlock;
import com.alibaba.druid.sql.dialect.sqlserver.ast.expr.SQLServerObjectReferenceExpr;
import com.alibaba.druid.sql.dialect.sqlserver.ast.stmt.SQLServerExecStatement;
import com.alibaba.druid.sql.dialect.sqlserver.ast.stmt.SQLServerInsertStatement;
import com.alibaba.druid.sql.dialect.sqlserver.visitor.SQLServerASTVisitor;
import com.alibaba.druid.sql.dialect.sqlserver.visitor.SQLServerASTVisitorAdapter;
import com.alibaba.druid.util.JdbcConstants;
import com.alibaba.druid.wall.Violation;
import com.alibaba.druid.wall.WallConfig;
import com.alibaba.druid.wall.WallProvider;
import com.alibaba.druid.wall.WallVisitor;
import com.alibaba.druid.wall.spi.WallVisitorUtils.WallTopStatementContext;
import com.alibaba.druid.wall.violation.ErrorCode;
import com.alibaba.druid.wall.violation.IllegalSQLObjectViolation;
import java.util.ArrayList;
import java.util.List;
public class SQLServerWallVisitor extends SQLServerASTVisitorAdapter implements WallVisitor, SQLServerASTVisitor {
private final WallConfig config;
private final WallProvider provider;
private final List<Violation> violations = new ArrayList<Violation>();
private boolean sqlModified = false;
public SQLServerWallVisitor(WallProvider provider){
this.config = provider.getConfig();
this.provider = provider;
}
@Override
public String getDbType() {
return JdbcConstants.SQL_SERVER;
}
@Override
public boolean isSqlModified() {
return sqlModified;
}
@Override
public void setSqlModified(boolean sqlModified) {
this.sqlModified = sqlModified;
}
@Override
public WallProvider getProvider() {
return provider;
}
@Override
public WallConfig getConfig() {
return this.config;
}
@Override
public void addViolation(Violation violation) {
this.violations.add(violation);
}
@Override
public List<Violation> getViolations() {
return violations;
}
@Override
public boolean isDenyTable(String name) {
if (!config.isTableCheck()) {
return false;
}
return !this.provider.checkDenyTable(name);
}
@Override
public String toSQL(SQLObject obj) {
return SQLUtils.toSQLServerString(obj);
}
public boolean visit(SQLIdentifierExpr x) {
// String name = x.getName();
// name = WallVisitorUtils.form(name);
// if (config.isVariantCheck() && config.getDenyVariants().contains(name)) {
// getViolations().add(new IllegalSQLObjectViolation(ErrorCode.VARIANT_DENY, "variable not allow : " + name,
// toSQL(x)));
// }
return true;
}
public boolean visit(SQLPropertyExpr x) {
WallVisitorUtils.check(this, x);
return true;
}
public boolean visit(SQLInListExpr x) {
WallVisitorUtils.check(this, x);
return true;
}
public boolean visit(SQLBinaryOpExpr x) {
return WallVisitorUtils.check(this, x);
}
@Override
public boolean visit(SQLMethodInvokeExpr x) {
if (x.getParent() instanceof SQLExprTableSource) {
WallVisitorUtils.checkFunctionInTableSource(this, x);
}
WallVisitorUtils.checkFunction(this, x);
return true;
}
@Override
public boolean visit(SQLServerExecStatement x) {
return false;
}
public boolean visit(SQLExprTableSource x) {
WallVisitorUtils.check(this, x);
return !(x.getExpr() instanceof SQLName);
}
public boolean visit(SQLSelectGroupByClause x) {
WallVisitorUtils.checkHaving(this, x.getHaving());
return true;
}
@Override
public boolean visit(SQLServerSelectQueryBlock x) {
WallVisitorUtils.checkSelelct(this, x);
return true;
}
@Override
public boolean visit(SQLSelectQueryBlock x) {
WallVisitorUtils.checkSelelct(this, x);
return true;
}
@Override
public boolean visit(SQLUnionQuery x) {
WallVisitorUtils.checkUnion(this, x);
return true;
}
public void preVisit(SQLObject x) {
WallVisitorUtils.preVisitCheck(this, x);
}
@Override
public boolean visit(SQLSelectStatement x) {
if (!config.isSelelctAllow()) {
this.getViolations().add(new IllegalSQLObjectViolation(ErrorCode.SELECT_NOT_ALLOW, "selelct not allow",
this.toSQL(x)));
return false;
}
WallVisitorUtils.initWallTopStatementContext();
return true;
}
@Override
public void endVisit(SQLSelectStatement x) {
WallVisitorUtils.clearWallTopStatementContext();
}
@Override
public boolean visit(SQLInsertStatement x) {
WallVisitorUtils.initWallTopStatementContext();
WallVisitorUtils.checkInsert(this, x);
return true;
}
@Override
public void endVisit(SQLInsertStatement x) {
WallVisitorUtils.clearWallTopStatementContext();
}
@Override
public boolean visit(SQLDeleteStatement x) {
WallVisitorUtils.checkDelete(this, x);
return true;
}
@Override
public boolean visit(SQLUpdateStatement x) {
WallVisitorUtils.initWallTopStatementContext();
WallVisitorUtils.checkUpdate(this, x);
return true;
}
@Override
public void endVisit(SQLUpdateStatement x) {
WallVisitorUtils.clearWallTopStatementContext();
}
public boolean visit(SQLVariantRefExpr x) {
String varName = x.getName();
if (varName == null) {
return false;
}
if (config.isVariantCheck() && varName.startsWith("@@")) {
final WallTopStatementContext topStatementContext = WallVisitorUtils.getWallTopStatementContext();
if (topStatementContext != null
&& (topStatementContext.fromSysSchema() || topStatementContext.fromSysTable())) {
return false;
}
boolean allow = true;
if (isDeny(varName) && (WallVisitorUtils.isWhereOrHaving(x) || WallVisitorUtils.checkSqlExpr(x))) {
allow = false;
}
if (!allow) {
violations.add(new IllegalSQLObjectViolation(ErrorCode.VARIANT_DENY, "variable not allow : "
+ x.getName(), toSQL(x)));
}
}
return false;
}
public boolean isDeny(String varName) {
if (varName.startsWith("@@")) {
varName = varName.substring(2);
}
return config.getDenyVariants().contains(varName);
}
@Override
public boolean visit(SQLServerObjectReferenceExpr x) {
return false;
}
@Override
public boolean visit(SQLServerInsertStatement x) {
return this.visit((SQLInsertStatement) x);
}
@Override
public void endVisit(SQLServerInsertStatement x) {
this.endVisit((SQLInsertStatement) x);
}
@Override
public boolean visit(SQLSelectItem x) {
WallVisitorUtils.check(this, x);
return true;
}
@Override
public boolean visit(SQLCreateTableStatement x) {
WallVisitorUtils.check(this, x);
return true;
}
@Override
public boolean visit(SQLAlterTableStatement x) {
WallVisitorUtils.check(this, x);
return true;
}
@Override
public boolean visit(SQLDropTableStatement x) {
WallVisitorUtils.check(this, x);
return true;
}
@Override
public boolean visit(SQLSetStatement x) {
return false;
}
@Override
public boolean visit(SQLCallStatement x) {
return false;
}
@Override
public boolean visit(SQLCreateTriggerStatement x) {
return false;
}
}