/
simple.go
53 lines (45 loc) · 1.22 KB
/
simple.go
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// Copyright (c) 2020, The Garble Authors.
// See LICENSE for licensing information.
package literals
import (
"go/ast"
"go/token"
mathrand "math/rand"
ah "github.com/z9001/garble/internal/asthelper"
)
type simple struct{}
// check that the obfuscator interface is implemented
var _ obfuscator = simple{}
func (simple) obfuscate(obfRand *mathrand.Rand, data []byte) *ast.BlockStmt {
key := make([]byte, len(data))
obfRand.Read(key)
op := randOperator(obfRand)
for i, b := range key {
data[i] = evalOperator(op, data[i], b)
}
return ah.BlockStmt(
&ast.AssignStmt{
Lhs: []ast.Expr{ast.NewIdent("key")},
Tok: token.DEFINE,
Rhs: []ast.Expr{ah.DataToByteSlice(key)},
},
&ast.AssignStmt{
Lhs: []ast.Expr{ast.NewIdent("data")},
Tok: token.DEFINE,
Rhs: []ast.Expr{ah.DataToByteSlice(data)},
},
&ast.RangeStmt{
Key: ast.NewIdent("i"),
Value: ast.NewIdent("b"),
Tok: token.DEFINE,
X: ast.NewIdent("key"),
Body: &ast.BlockStmt{List: []ast.Stmt{
&ast.AssignStmt{
Lhs: []ast.Expr{ah.IndexExpr("data", ast.NewIdent("i"))},
Tok: token.ASSIGN,
Rhs: []ast.Expr{operatorToReversedBinaryExpr(op, ah.IndexExpr("data", ast.NewIdent("i")), ast.NewIdent("b"))},
},
}},
},
)
}