gopkg.in/alecthomas/gometalinter.v3@v3.0.0/_linters/src/github.com/securego/gosec/resolve.go (about)

     1  // (c) Copyright 2016 Hewlett Packard Enterprise Development LP
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package gosec
    16  
    17  import "go/ast"
    18  
    19  func resolveIdent(n *ast.Ident, c *Context) bool {
    20  
    21  	if n.Obj == nil || n.Obj.Kind != ast.Var {
    22  		return true
    23  	}
    24  	if node, ok := n.Obj.Decl.(ast.Node); ok {
    25  		return TryResolve(node, c)
    26  	}
    27  	return false
    28  }
    29  
    30  func resolveAssign(n *ast.AssignStmt, c *Context) bool {
    31  	for _, arg := range n.Rhs {
    32  		if !TryResolve(arg, c) {
    33  			return false
    34  		}
    35  	}
    36  	return true
    37  }
    38  
    39  func resolveCompLit(n *ast.CompositeLit, c *Context) bool {
    40  	for _, arg := range n.Elts {
    41  		if !TryResolve(arg, c) {
    42  			return false
    43  		}
    44  	}
    45  	return true
    46  }
    47  
    48  func resolveBinExpr(n *ast.BinaryExpr, c *Context) bool {
    49  	return (TryResolve(n.X, c) && TryResolve(n.Y, c))
    50  }
    51  
    52  func resolveCallExpr(n *ast.CallExpr, c *Context) bool {
    53  	// TODO(tkelsey): next step, full function resolution
    54  	return false
    55  }
    56  
    57  // TryResolve will attempt, given a subtree starting at some ATS node, to resolve
    58  // all values contained within to a known constant. It is used to check for any
    59  // unkown values in compound expressions.
    60  func TryResolve(n ast.Node, c *Context) bool {
    61  	switch node := n.(type) {
    62  	case *ast.BasicLit:
    63  		return true
    64  
    65  	case *ast.CompositeLit:
    66  		return resolveCompLit(node, c)
    67  
    68  	case *ast.Ident:
    69  		return resolveIdent(node, c)
    70  
    71  	case *ast.AssignStmt:
    72  		return resolveAssign(node, c)
    73  
    74  	case *ast.CallExpr:
    75  		return resolveCallExpr(node, c)
    76  
    77  	case *ast.BinaryExpr:
    78  		return resolveBinExpr(node, c)
    79  	}
    80  
    81  	return false
    82  }