61 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			61 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
package rules
 | 
						|
 | 
						|
import (
 | 
						|
	"go/ast"
 | 
						|
	"go/types"
 | 
						|
 | 
						|
	"github.com/securego/gosec"
 | 
						|
)
 | 
						|
 | 
						|
type archive struct {
 | 
						|
	gosec.MetaData
 | 
						|
	calls   gosec.CallList
 | 
						|
	argType string
 | 
						|
}
 | 
						|
 | 
						|
func (a *archive) ID() string {
 | 
						|
	return a.MetaData.ID
 | 
						|
}
 | 
						|
 | 
						|
// Match inspects AST nodes to determine if the filepath.Joins uses any argument derived from type zip.File
 | 
						|
func (a *archive) Match(n ast.Node, c *gosec.Context) (*gosec.Issue, error) {
 | 
						|
	if node := a.calls.ContainsCallExpr(n, c, false); node != nil {
 | 
						|
		for _, arg := range node.Args {
 | 
						|
			var argType types.Type
 | 
						|
			if selector, ok := arg.(*ast.SelectorExpr); ok {
 | 
						|
				argType = c.Info.TypeOf(selector.X)
 | 
						|
			} else if ident, ok := arg.(*ast.Ident); ok {
 | 
						|
				if ident.Obj != nil && ident.Obj.Kind == ast.Var {
 | 
						|
					decl := ident.Obj.Decl
 | 
						|
					if assign, ok := decl.(*ast.AssignStmt); ok {
 | 
						|
						if selector, ok := assign.Rhs[0].(*ast.SelectorExpr); ok {
 | 
						|
							argType = c.Info.TypeOf(selector.X)
 | 
						|
						}
 | 
						|
					}
 | 
						|
				}
 | 
						|
			}
 | 
						|
 | 
						|
			if argType != nil && argType.String() == a.argType {
 | 
						|
				return gosec.NewIssue(c, n, a.ID(), a.What, a.Severity, a.Confidence), nil
 | 
						|
			}
 | 
						|
		}
 | 
						|
	}
 | 
						|
	return nil, nil
 | 
						|
}
 | 
						|
 | 
						|
// NewArchive creates a new rule which detects the file traversal when extracting zip archives
 | 
						|
func NewArchive(id string, conf gosec.Config) (gosec.Rule, []ast.Node) {
 | 
						|
	calls := gosec.NewCallList()
 | 
						|
	calls.Add("path/filepath", "Join")
 | 
						|
	return &archive{
 | 
						|
		calls:   calls,
 | 
						|
		argType: "*archive/zip.File",
 | 
						|
		MetaData: gosec.MetaData{
 | 
						|
			ID:         id,
 | 
						|
			Severity:   gosec.Medium,
 | 
						|
			Confidence: gosec.High,
 | 
						|
			What:       "File traversal when extracting zip archive",
 | 
						|
		},
 | 
						|
	}, []ast.Node{(*ast.CallExpr)(nil)}
 | 
						|
}
 |