mirror of
https://gerrit.wikimedia.org/r/mediawiki/extensions/AbuseFilter.git
synced 2024-11-27 23:40:19 +00:00
24888bea15
Protected effectively means "public to subclasses" and should be avoided for the same reasons as marking everything as public should be avoided. Change-Id: Iba674b486ce53fd1f94f70163d47824e969abb77
680 lines
18 KiB
PHP
680 lines
18 KiB
PHP
<?php
|
|
|
|
namespace MediaWiki\Extension\AbuseFilter\Parser;
|
|
|
|
use InvalidArgumentException;
|
|
use LogicException;
|
|
use MediaWiki\Extension\AbuseFilter\KeywordsManager;
|
|
use MediaWiki\Extension\AbuseFilter\Parser\Exception\InternalException;
|
|
use MediaWiki\Extension\AbuseFilter\Parser\Exception\UserVisibleException;
|
|
use Message;
|
|
|
|
/**
|
|
* SyntaxChecker statically analyzes the code without actually running it.
|
|
* Currently, it only checks for
|
|
*
|
|
* - unbound variables
|
|
* - unused variables: note that a := 1; a := 1; a
|
|
* is considered OK even though the first `a` seems unused
|
|
* because the pattern "a := null; if ... then (a := ...) end; ..."
|
|
* should not count first `a` as unused.
|
|
* - assignment to built-in identifiers
|
|
* - invalid function call (arity mismatch, non-valid function)
|
|
* - first-order information of `set_var` and `set`
|
|
*
|
|
* Because it doesn't cover all checks that the current Check Syntax does,
|
|
* it is currently complementary to the current Check Syntax.
|
|
* In the future, it could subsume the current Check Syntax, and could be
|
|
* extended to perform type checking or type inference.
|
|
*/
|
|
class SyntaxChecker {
|
|
/**
|
|
* @var AFPTreeNode|null Root of the AST to check
|
|
*/
|
|
private $treeRoot;
|
|
|
|
/** @var KeywordsManager */
|
|
private $keywordsManager;
|
|
|
|
public const MCONSERVATIVE = 'MODE_CONSERVATIVE';
|
|
public const MLIBERAL = 'MODE_LIBERAL';
|
|
public const DUMMYPOS = 0;
|
|
public const CACHE_VERSION = 1;
|
|
|
|
/**
|
|
* @var string The mode of checking. The value should be either
|
|
*
|
|
* - MLIBERAL: which guarantees that all user-defined variables
|
|
* will be bound, but incompatible with what the evaluator currently
|
|
* permits. E.g.,
|
|
*
|
|
* if true then (a := 1) else null end; a
|
|
*
|
|
* is rejected in this mode, even though `a` is in fact always bound.
|
|
*
|
|
* - MCONSERVATIVE which is compatible with what the evaluator
|
|
* currently permits, but could allow undefined variables to occur.
|
|
* E.g.,
|
|
*
|
|
* if false then (a := 1) else null end; a
|
|
*
|
|
* is accepted in this mode, even though `a` is in fact always unbound.
|
|
*/
|
|
private $mode;
|
|
|
|
/**
|
|
* @var bool Whether we want to check for unused variables
|
|
*/
|
|
private $checkUnusedVars;
|
|
|
|
/**
|
|
* @param AFPSyntaxTree $tree
|
|
* @param KeywordsManager $keywordsManager
|
|
* @param string $mode
|
|
* @param bool $checkUnusedVars
|
|
*/
|
|
public function __construct(
|
|
AFPSyntaxTree $tree,
|
|
KeywordsManager $keywordsManager,
|
|
string $mode = self::MCONSERVATIVE,
|
|
bool $checkUnusedVars = false
|
|
) {
|
|
$this->treeRoot = $tree->getRoot();
|
|
$this->keywordsManager = $keywordsManager;
|
|
$this->mode = $mode;
|
|
$this->checkUnusedVars = $checkUnusedVars;
|
|
}
|
|
|
|
/**
|
|
* Start the static analysis
|
|
*
|
|
* @throws UserVisibleException
|
|
*/
|
|
public function start(): void {
|
|
if ( !$this->treeRoot ) {
|
|
return;
|
|
}
|
|
$bound = $this->check( $this->desugar( $this->treeRoot ), [] );
|
|
$unused = array_keys( array_filter( $bound, static function ( $v ) {
|
|
return !$v;
|
|
} ) );
|
|
if ( $this->checkUnusedVars && $unused ) {
|
|
throw new UserVisibleException(
|
|
'unusedvars',
|
|
self::DUMMYPOS,
|
|
[ Message::listParam( $unused, 'comma' ) ]
|
|
);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Remove syntactic sugar so that we don't need to deal with
|
|
* too many cases.
|
|
*
|
|
* This could benefit the evaluator as well, but for now, this is
|
|
* only used for static analysis.
|
|
*
|
|
* Postcondition:
|
|
* - The tree will not contain nodes of
|
|
* type ASSIGNMENT, LOGIC, COMPARE, SUM_REL, MUL_REL, POW,
|
|
* KEYWORD_OPERATOR, and ARRAY_INDEX
|
|
* - The tree may additionally contain a node of type BINOP.
|
|
* - The tree should not have set_var function application.
|
|
* - Conditionals will have both branches.
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @return AFPTreeNode
|
|
* @throws InternalException
|
|
*/
|
|
private function desugar( AFPTreeNode $node ): AFPTreeNode {
|
|
switch ( $node->type ) {
|
|
case AFPTreeNode::ATOM:
|
|
return $node;
|
|
|
|
case AFPTreeNode::FUNCTION_CALL:
|
|
if ( $node->children[0] === 'set_var' ) {
|
|
$node->children[0] = 'set';
|
|
}
|
|
return $this->newNodeMapExceptFirst( $node );
|
|
|
|
case AFPTreeNode::ARRAY_INDEX:
|
|
return $this->newNodeNamedBinop( $node, '[]' );
|
|
|
|
case AFPTreeNode::POW:
|
|
return $this->newNodeNamedBinop( $node, '**' );
|
|
|
|
case AFPTreeNode::UNARY:
|
|
case AFPTreeNode::INDEX_ASSIGNMENT:
|
|
case AFPTreeNode::ARRAY_APPEND:
|
|
return $this->newNodeMapExceptFirst( $node );
|
|
|
|
case AFPTreeNode::BOOL_INVERT:
|
|
/*
|
|
* @todo this should really be combined with UNARY,
|
|
* but let's wait to change the meaning of UNARY across
|
|
* the codebase together
|
|
*/
|
|
return $this->newNodeMapAll( $node );
|
|
|
|
case AFPTreeNode::KEYWORD_OPERATOR:
|
|
case AFPTreeNode::MUL_REL:
|
|
case AFPTreeNode::SUM_REL:
|
|
case AFPTreeNode::COMPARE:
|
|
return $this->newNodeBinop( $node );
|
|
|
|
case AFPTreeNode::LOGIC:
|
|
$result = $this->newNodeBinop( $node );
|
|
list( $op, $left, $right ) = $result->children;
|
|
if ( $op === '&' || $op === '|' ) {
|
|
return $this->desugarAndOr( $op, $left, $right, $node->position );
|
|
} else {
|
|
return $result;
|
|
}
|
|
|
|
case AFPTreeNode::ARRAY_DEFINITION:
|
|
case AFPTreeNode::SEMICOLON:
|
|
return $this->newNodeMapAll( $node );
|
|
|
|
case AFPTreeNode::CONDITIONAL:
|
|
if ( $node->children[2] === null ) {
|
|
$node->children[2] = new AFPTreeNode(
|
|
AFPTreeNode::ATOM,
|
|
new AFPToken(
|
|
AFPToken::TKEYWORD,
|
|
"null",
|
|
$node->position
|
|
),
|
|
$node->position
|
|
);
|
|
}
|
|
return $this->newNodeMapAll( $node );
|
|
|
|
case AFPTreeNode::ASSIGNMENT:
|
|
list( $varname, $value ) = $node->children;
|
|
|
|
return new AFPTreeNode(
|
|
AFPTreeNode::FUNCTION_CALL,
|
|
[
|
|
"set",
|
|
new AFPTreeNode(
|
|
AFPTreeNode::ATOM,
|
|
new AFPToken(
|
|
AFPToken::TSTRING,
|
|
$varname,
|
|
$node->position
|
|
),
|
|
$node->position
|
|
),
|
|
$this->desugar( $value )
|
|
],
|
|
$node->position
|
|
);
|
|
|
|
default:
|
|
// @codeCoverageIgnoreStart
|
|
throw new InternalException( "Unknown node type passed: {$node->type}" );
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param string $op
|
|
* @param AFPTreeNode $left
|
|
* @param AFPTreeNode $right
|
|
* @param int $position
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function desugarAndOr(
|
|
string $op,
|
|
AFPTreeNode $left,
|
|
AFPTreeNode $right,
|
|
int $position
|
|
): AFPTreeNode {
|
|
$trueNode = new AFPTreeNode(
|
|
AFPTreeNode::ATOM,
|
|
new AFPToken(
|
|
AFPToken::TKEYWORD,
|
|
"true",
|
|
$position
|
|
),
|
|
$position
|
|
);
|
|
$falseNode = new AFPTreeNode(
|
|
AFPTreeNode::ATOM,
|
|
new AFPToken(
|
|
AFPToken::TKEYWORD,
|
|
"false",
|
|
$position
|
|
),
|
|
$position
|
|
);
|
|
$conditionalNode = new AFPTreeNode(
|
|
AFPTreeNode::CONDITIONAL,
|
|
[
|
|
$right,
|
|
$trueNode,
|
|
$falseNode
|
|
],
|
|
$position
|
|
);
|
|
|
|
if ( $op === '&' ) {
|
|
// <a> & <b> is supposed to be equivalent to
|
|
// if <a> then (if <b> then true else false) else false end
|
|
// See T237336 for why this is currently not the case.
|
|
return new AFPTreeNode(
|
|
AFPTreeNode::CONDITIONAL,
|
|
[
|
|
$left,
|
|
$conditionalNode,
|
|
$falseNode
|
|
],
|
|
$position
|
|
);
|
|
} elseif ( $op === '|' ) {
|
|
// <a> | <b> is supposed to be equivalent to
|
|
// if <a> then true else (if <b> then true else false) end
|
|
// See T237336 for why this is currently not the case.
|
|
return new AFPTreeNode(
|
|
AFPTreeNode::CONDITIONAL,
|
|
[
|
|
$left,
|
|
$trueNode,
|
|
$conditionalNode
|
|
],
|
|
$position
|
|
);
|
|
} else {
|
|
// @codeCoverageIgnoreStart
|
|
throw new InternalException( "Unknown operator: {$op}" );
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Construct a new node with information based on the old node but
|
|
* with different children
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @param AFPTreeNode[]|string[]|AFPToken $children
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function newNode( AFPTreeNode $node, $children ): AFPTreeNode {
|
|
return new AFPTreeNode( $node->type, $children, $node->position );
|
|
}
|
|
|
|
/**
|
|
* Construct a new node with information based on the old node but
|
|
* with different type
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @param string $type
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function newNodeReplaceType(
|
|
AFPTreeNode $node,
|
|
string $type
|
|
): AFPTreeNode {
|
|
return new AFPTreeNode( $type, $node->children, $node->position );
|
|
}
|
|
|
|
/**
|
|
* Recursively desugar on all children
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function newNodeMapAll( AFPTreeNode $node ): AFPTreeNode {
|
|
$children = $node->children;
|
|
if ( !is_array( $children ) ) {
|
|
// @codeCoverageIgnoreStart
|
|
throw new LogicException(
|
|
"Unexpected non-array children of an AFPTreeNode of type " .
|
|
"{$node->type} at position {$node->position}"
|
|
);
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
return $this->newNode( $node, array_map( [ $this, 'desugar' ], $children ) );
|
|
}
|
|
|
|
/**
|
|
* Recursively desugar on all children except the first one
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function newNodeMapExceptFirst( AFPTreeNode $node ): AFPTreeNode {
|
|
$items = [ $node->children[0] ];
|
|
$args = array_slice( $node->children, 1 );
|
|
foreach ( $args as $el ) {
|
|
$items[] = $this->desugar( $el );
|
|
}
|
|
return $this->newNode( $node, $items );
|
|
}
|
|
|
|
/**
|
|
* Convert a node with an operation into a BINOP
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function newNodeBinop( AFPTreeNode $node ): AFPTreeNode {
|
|
return $this->newNodeReplaceType(
|
|
$this->newNodeMapExceptFirst( $node ),
|
|
AFPTreeNode::BINOP
|
|
);
|
|
}
|
|
|
|
/**
|
|
* Convert a node without an operation into a BINOP with the specified operation
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @param string $op
|
|
* @return AFPTreeNode
|
|
*/
|
|
private function newNodeNamedBinop(
|
|
AFPTreeNode $node,
|
|
string $op
|
|
): AFPTreeNode {
|
|
$items = $this->newNodeMapAll( $node )->children;
|
|
array_unshift( $items, $op );
|
|
return $this->newNodeReplaceType(
|
|
$this->newNode( $node, $items ),
|
|
AFPTreeNode::BINOP
|
|
);
|
|
}
|
|
|
|
/**
|
|
* - Statically compute what are bound after evaluating $node,
|
|
* provided that variables in $bound are already bound.
|
|
* - Similarly compute for each bound variable after evaluating $node
|
|
* whether it is used provided that we already have $bound
|
|
* that contains necessary information.
|
|
* - Ensure function application's validity.
|
|
* - Ensure that the first argument of set is a literal string.
|
|
* - Ensure that all assignment is not done on built-in identifier.
|
|
*
|
|
* Precondition:
|
|
* - The tree $node should be desugared and normalized.
|
|
*
|
|
* Postcondition:
|
|
* - $node is guaranteed to have no unbound variables
|
|
* provided that variables in $bound are already bound
|
|
* (for the definition of unbound variable indicated by $this->mode)
|
|
* - All function applications should be valid and have correct arity.
|
|
* - The set function application's first argument should be
|
|
* a literal string.
|
|
*
|
|
* @param AFPTreeNode $node
|
|
* @param bool[] $bound Map of [ variable_name => used ]
|
|
* @return bool[] Map of [ variable_name => used ]
|
|
* @throws UserVisibleException
|
|
* @throws InternalException
|
|
*/
|
|
private function check( AFPTreeNode $node, array $bound ): array {
|
|
switch ( $node->type ) {
|
|
// phpcs:ignore PSR2.ControlStructures.SwitchDeclaration.TerminatingComment
|
|
case AFPTreeNode::ATOM:
|
|
$tok = $node->children;
|
|
switch ( $tok->type ) {
|
|
case AFPToken::TID:
|
|
return $this->lookupVar(
|
|
$tok->value,
|
|
$tok->pos,
|
|
$bound
|
|
);
|
|
|
|
case AFPToken::TSTRING:
|
|
case AFPToken::TFLOAT:
|
|
case AFPToken::TINT:
|
|
case AFPToken::TKEYWORD:
|
|
return $bound;
|
|
|
|
default:
|
|
// @codeCoverageIgnoreStart
|
|
throw new InternalException( "Unknown token {$tok->type} provided in the ATOM node" );
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
case AFPTreeNode::ARRAY_DEFINITION:
|
|
// @phan-suppress-next-line PhanTypeSuspiciousNonTraversableForeach children is array here
|
|
foreach ( $node->children as $el ) {
|
|
$bound = $this->check( $el, $bound );
|
|
}
|
|
return $bound;
|
|
|
|
case AFPTreeNode::FUNCTION_CALL:
|
|
$fname = $node->children[0];
|
|
$args = array_slice( $node->children, 1 );
|
|
if ( !array_key_exists( $fname, FilterEvaluator::FUNCTIONS ) ) {
|
|
throw new UserVisibleException(
|
|
'unknownfunction',
|
|
$node->position,
|
|
[ $fname ]
|
|
);
|
|
}
|
|
$this->checkArgCount( $args, $fname, $node->position );
|
|
|
|
if ( $fname === 'set' ) {
|
|
// arity is checked, so we know $args[0] and $args[1] exist
|
|
$tok = $args[0]->children;
|
|
|
|
if (
|
|
!( $tok instanceof AFPToken ) ||
|
|
$tok->type !== AFPToken::TSTRING
|
|
) {
|
|
throw new UserVisibleException(
|
|
'variablevariable',
|
|
$node->position,
|
|
[]
|
|
);
|
|
}
|
|
|
|
$bound = $this->check( $args[1], $bound );
|
|
// set the variable as unused
|
|
return $this->assignVar(
|
|
$tok->value,
|
|
$tok->pos,
|
|
$bound
|
|
);
|
|
} else {
|
|
foreach ( $args as $arg ) {
|
|
$bound = $this->check( $arg, $bound );
|
|
}
|
|
return $bound;
|
|
}
|
|
|
|
case AFPTreeNode::BINOP:
|
|
list( , $left, $right ) = $node->children;
|
|
return $this->check( $right, $this->check( $left, $bound ) );
|
|
|
|
case AFPTreeNode::UNARY:
|
|
list( , $argument ) = $node->children;
|
|
return $this->check( $argument, $bound );
|
|
|
|
case AFPTreeNode::BOOL_INVERT:
|
|
list( $argument ) = $node->children;
|
|
return $this->check( $argument, $bound );
|
|
// phpcs:ignore PSR2.ControlStructures.SwitchDeclaration.TerminatingComment
|
|
case AFPTreeNode::CONDITIONAL:
|
|
list( $condition, $exprIfTrue, $exprIfFalse ) = $node->children;
|
|
$bound = $this->check( $condition, $bound );
|
|
$boundLeft = $this->check( $exprIfTrue, $bound );
|
|
$boundRight = $this->check( $exprIfFalse, $bound );
|
|
switch ( $this->mode ) {
|
|
case self::MCONSERVATIVE:
|
|
return $this->mapUnion( $boundLeft, $boundRight );
|
|
case self::MLIBERAL:
|
|
return $this->mapIntersect( $boundLeft, $boundRight );
|
|
default:
|
|
// @codeCoverageIgnoreStart
|
|
throw new LogicException( "Unknown mode: {$this->mode}" );
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
|
|
case AFPTreeNode::INDEX_ASSIGNMENT:
|
|
list( $varName, $offset, $value ) = $node->children;
|
|
|
|
// deal with unbound $varName
|
|
$bound = $this->lookupVar( $varName, $node->position, $bound );
|
|
$bound = $this->check( $offset, $bound );
|
|
$bound = $this->check( $value, $bound );
|
|
// deal with built-in $varName and set $varName as unused
|
|
return $this->assignVar( $varName, $node->position, $bound );
|
|
|
|
case AFPTreeNode::ARRAY_APPEND:
|
|
list( $varName, $value ) = $node->children;
|
|
|
|
// deal with unbound $varName
|
|
$bound = $this->lookupVar( $varName, $node->position, $bound );
|
|
$bound = $this->check( $value, $bound );
|
|
// deal with built-in $varName and set $varName as unused
|
|
return $this->assignVar( $varName, $node->position, $bound );
|
|
|
|
case AFPTreeNode::SEMICOLON:
|
|
// @phan-suppress-next-line PhanTypeSuspiciousNonTraversableForeach children is array here
|
|
foreach ( $node->children as $statement ) {
|
|
$bound = $this->check( $statement, $bound );
|
|
}
|
|
return $bound;
|
|
|
|
default:
|
|
// @codeCoverageIgnoreStart
|
|
throw new LogicException( "Unknown type: {$node->type}" );
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
}
|
|
|
|
/**
|
|
* @param array $left
|
|
* @param array $right
|
|
* @return array
|
|
*/
|
|
private function mapUnion( array $left, array $right ): array {
|
|
foreach ( $right as $key => $val ) {
|
|
if ( array_key_exists( $key, $left ) ) {
|
|
$left[ $key ] = $left[ $key ] || $val;
|
|
} else {
|
|
$left[ $key ] = $val;
|
|
}
|
|
}
|
|
return $left;
|
|
}
|
|
|
|
/**
|
|
* @param array $left
|
|
* @param array $right
|
|
* @return array
|
|
*/
|
|
private function mapIntersect( array $left, array $right ): array {
|
|
$keys = array_intersect_key( $left, $right );
|
|
$result = [];
|
|
foreach ( $keys as $key => $val ) {
|
|
$result[ $key ] = $left[ $key ] || $right[ $key ];
|
|
}
|
|
return $result;
|
|
}
|
|
|
|
/**
|
|
* @param string $var
|
|
* @param int $pos
|
|
* @param array $bound
|
|
* @return array
|
|
*/
|
|
private function assignVar( string $var, int $pos, array $bound ): array {
|
|
$var = strtolower( $var );
|
|
if ( $this->isReservedIdentifier( $var ) ) {
|
|
throw new UserVisibleException(
|
|
'overridebuiltin',
|
|
$pos,
|
|
[ $var ]
|
|
);
|
|
}
|
|
$bound[ $var ] = false;
|
|
return $bound;
|
|
}
|
|
|
|
/**
|
|
* @param string $var
|
|
* @param int $pos
|
|
* @param array $bound
|
|
* @return array
|
|
*/
|
|
private function lookupVar( string $var, int $pos, array $bound ): array {
|
|
$var = strtolower( $var );
|
|
if ( array_key_exists( $var, $bound ) ) {
|
|
// user-defined variable
|
|
$bound[ $var ] = true;
|
|
return $bound;
|
|
} elseif ( $this->keywordsManager->isVarDisabled( $var ) ) {
|
|
// disabled built-in variables
|
|
throw new UserVisibleException(
|
|
'disabledvar',
|
|
$pos,
|
|
[ $var ]
|
|
);
|
|
} elseif ( $this->keywordsManager->varExists( $var ) ) {
|
|
// non-disabled built-in variables
|
|
return $bound;
|
|
} elseif ( $this->isReservedIdentifier( $var ) ) {
|
|
// other built-in identifiers
|
|
throw new UserVisibleException(
|
|
'usebuiltin',
|
|
$pos,
|
|
[ $var ]
|
|
);
|
|
} else {
|
|
// unbound variables
|
|
throw new UserVisibleException(
|
|
'unrecognisedvar',
|
|
$pos,
|
|
[ $var ]
|
|
);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Check that a built-in function has been provided the right amount of arguments
|
|
*
|
|
* @param array $args The arguments supplied to the function
|
|
* @param string $func The function name
|
|
* @param int $position
|
|
* @throws UserVisibleException
|
|
*/
|
|
private function checkArgCount( array $args, string $func, int $position ): void {
|
|
if ( !array_key_exists( $func, FilterEvaluator::FUNC_ARG_COUNT ) ) {
|
|
// @codeCoverageIgnoreStart
|
|
throw new InvalidArgumentException( "$func is not a valid function." );
|
|
// @codeCoverageIgnoreEnd
|
|
}
|
|
list( $min, $max ) = FilterEvaluator::FUNC_ARG_COUNT[ $func ];
|
|
if ( count( $args ) < $min ) {
|
|
throw new UserVisibleException(
|
|
$min === 1 ? 'noparams' : 'notenoughargs',
|
|
$position,
|
|
[ $func, $min, count( $args ) ]
|
|
);
|
|
} elseif ( count( $args ) > $max ) {
|
|
throw new UserVisibleException(
|
|
'toomanyargs',
|
|
$position,
|
|
[ $func, $max, count( $args ) ]
|
|
);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Check whether the given name is a reserved identifier, e.g. the name of a built-in variable,
|
|
* function, or keyword.
|
|
*
|
|
* @param string $name
|
|
* @return bool
|
|
*/
|
|
private function isReservedIdentifier( string $name ): bool {
|
|
return $this->keywordsManager->varExists( $name ) ||
|
|
array_key_exists( $name, FilterEvaluator::FUNCTIONS ) ||
|
|
// We need to check for true, false, if/then/else etc. because, even if they have a different
|
|
// AFPToken type, they may be used inside set/set_var()
|
|
in_array( $name, AbuseFilterTokenizer::KEYWORDS, true );
|
|
}
|
|
}
|