Merge pull request #10 from gettaxi/master

Add gorm and sqlx support, make easy add new other ORM

Author: clundquist-stripe

README.md

@@ -31,8 +31,8 @@ How does it work?
 -----------------
 
 SafeSQL uses the static analysis utilities in [go/tools][tools] to search for
-all call sites of each of the `query` functions in package [database/sql][sql]
-(i.e., functions which accept a `string` parameter named `query`). It then makes
+all call sites of each of the `query` functions in packages ([database/sql][sql],[github.com/jinzhu/gorm][gorm],[github.com/jmoiron/sqlx][sqlx])
+(i.e., functions which accept a parameter named `query`,`sql`). It then makes
 sure that every such call site uses a query that is a compile-time constant.
 
 The principle behind SafeSQL's safety guarantees is that queries that are
@@ -44,6 +44,8 @@ will not be allowed.
 
 [tools]: https://godoc.org/golang.org/x/tools/go
 [sql]: http://golang.org/pkg/database/sql/
+[sqlx]: https://github.com/jmoiron/sqlx
+[gorm]: https://github.com/jinzhu/gorm
 
 False positives
 ---------------
@@ -66,8 +68,6 @@ a fundamental limitation: SafeSQL could recursively trace the `query` argument
 through every intervening helper function to ensure that its argument is always
 constant, but this code has yet to be written.
 
-If you use a wrapper for `database/sql` (e.g., [`sqlx`][sqlx]), it's likely
-SafeSQL will not work for you because of this.
 
 The second sort of false positive is based on a limitation in the sort of
 analysis SafeSQL performs: there are many safe SQL statements which are not
@@ -76,4 +76,3 @@ static analysis techniques (such as taint analysis) or user-provided safety
 annotations would be able to reduce the number of false positives, but this is
 expected to be a significant undertaking.
 
-[sqlx]: https://github.com/jmoiron/sqlx

safesql.go

@@ -9,6 +9,7 @@ import (
 	"go/build"
 	"go/types"
 	"os"
+
 	"path/filepath"
 	"strings"
 
@@ -19,6 +20,27 @@ import (
 	"golang.org/x/tools/go/ssa/ssautil"
 )
 
+type sqlPackage struct {
+	packageName string
+	paramNames  []string
+	enable      bool
+}
+
+var sqlPackages = []sqlPackage{
+	{
+		packageName: "database/sql",
+		paramNames:  []string{"query"},
+	},
+	{
+		packageName: "github.com/jinzhu/gorm",
+		paramNames:  []string{"sql", "query"},
+	},
+	{
+		packageName: "github.com/jmoiron/sqlx",
+		paramNames:  []string{"query"},
+	},
+}
+
 func main() {
 	var verbose, quiet bool
 	flag.BoolVar(&verbose, "v", false, "Verbose mode")
@@ -38,21 +60,45 @@ func main() {
 	c := loader.Config{
 		FindPackage: FindPackage,
 	}
-	c.Import("database/sql")
 	for _, pkg := range pkgs {
 		c.Import(pkg)
 	}
 	p, err := c.Load()
+
 	if err != nil {
 		fmt.Printf("error loading packages %v: %v\n", pkgs, err)
 		os.Exit(2)
 	}
+
+	imports := getImports(p)
+	existOne := false
+	for i := range sqlPackages {
+		if _, exist := imports[sqlPackages[i].packageName]; exist {
+			if verbose {
+				fmt.Printf("Enabling support for %s\n", sqlPackages[i].packageName)
+			}
+			sqlPackages[i].enable = true
+			existOne = true
+		}
+	}
+	if !existOne {
+		fmt.Printf("No packages in %v include a supported database driver", pkgs)
+		os.Exit(2)
+	}
+
 	s := ssautil.CreateProgram(p, 0)
 	s.Build()
 
-	qms := FindQueryMethods(p.Package("database/sql").Pkg, s)
+	qms := make([]*QueryMethod, 0)
+
+	for i := range sqlPackages {
+		if sqlPackages[i].enable {
+			qms = append(qms, FindQueryMethods(sqlPackages[i], p.Package(sqlPackages[i].packageName).Pkg, s)...)
+		}
+	}
+
 	if verbose {
-		fmt.Println("database/sql functions that accept queries:")
+		fmt.Println("database driver functions that accept queries:")
 		for _, m := range qms {
 			fmt.Printf("- %s (param %d)\n", m.Func, m.Param)
 		}
@@ -75,21 +121,27 @@ func main() {
 	}
 
 	bad := FindNonConstCalls(res.CallGraph, qms)
+
 	if len(bad) == 0 {
 		if !quiet {
 			fmt.Println(`You're safe from SQL injection! Yay \o/`)
 		}
 		return
 	}
 
-	fmt.Printf("Found %d potentially unsafe SQL statements:\n", len(bad))
+	if verbose {
+		fmt.Printf("Found %d potentially unsafe SQL statements:\n", len(bad))
+	}
+
 	for _, ci := range bad {
 		pos := p.Fset.Position(ci.Pos())
 		fmt.Printf("- %s\n", pos)
 	}
-	fmt.Println("Please ensure that all SQL queries you use are compile-time constants.")
-	fmt.Println("You should always use parameterized queries or prepared statements")
-	fmt.Println("instead of building queries from strings.")
+	if verbose {
+		fmt.Println("Please ensure that all SQL queries you use are compile-time constants.")
+		fmt.Println("You should always use parameterized queries or prepared statements")
+		fmt.Println("instead of building queries from strings.")
+	}
 	os.Exit(1)
 }
 
@@ -104,7 +156,7 @@ type QueryMethod struct {
 
 // FindQueryMethods locates all methods in the given package (assumed to be
 // package database/sql) with a string parameter named "query".
-func FindQueryMethods(sql *types.Package, ssa *ssa.Program) []*QueryMethod {
+func FindQueryMethods(sqlPackages sqlPackage, sql *types.Package, ssa *ssa.Program) []*QueryMethod {
 	methods := make([]*QueryMethod, 0)
 	scope := sql.Scope()
 	for _, name := range scope.Names() {
@@ -122,7 +174,7 @@ func FindQueryMethods(sql *types.Package, ssa *ssa.Program) []*QueryMethod {
 				continue
 			}
 			s := m.Type().(*types.Signature)
-			if num, ok := FuncHasQuery(s); ok {
+			if num, ok := FuncHasQuery(sqlPackages, s); ok {
 				methods = append(methods, &QueryMethod{
 					Func:     m,
 					SSA:      ssa.FuncValue(m),
@@ -135,16 +187,16 @@ func FindQueryMethods(sql *types.Package, ssa *ssa.Program) []*QueryMethod {
 	return methods
 }
 
-var stringType types.Type = types.Typ[types.String]
-
 // FuncHasQuery returns the offset of the string parameter named "query", or
 // none if no such parameter exists.
-func FuncHasQuery(s *types.Signature) (offset int, ok bool) {
+func FuncHasQuery(sqlPackages sqlPackage, s *types.Signature) (offset int, ok bool) {
 	params := s.Params()
 	for i := 0; i < params.Len(); i++ {
 		v := params.At(i)
-		if v.Name() == "query" && v.Type() == stringType {
-			return i, true
+		for _, paramName := range sqlPackages.paramNames {
+			if v.Name() == paramName {
+				return i, true
+			}
 		}
 	}
 	return 0, false
@@ -164,6 +216,16 @@ func FindMains(p *loader.Program, s *ssa.Program) []*ssa.Package {
 	return mains
 }
 
+func getImports(p *loader.Program) map[string]interface{} {
+	pkgs := make(map[string]interface{})
+	for _, pkg := range p.AllPackages {
+		if pkg.Importable {
+			pkgs[pkg.Pkg.Path()] = nil
+		}
+	}
+	return pkgs
+}
+
 // FindNonConstCalls returns the set of callsites of the given set of methods
 // for which the "query" parameter is not a compile-time constant.
 func FindNonConstCalls(cg *callgraph.Graph, qms []*QueryMethod) []ssa.CallInstruction {
@@ -186,6 +248,18 @@ func FindNonConstCalls(cg *callgraph.Graph, qms []*QueryMethod) []ssa.CallInstru
 			if _, ok := okFuncs[edge.Site.Parent()]; ok {
 				continue
 			}
+
+			isInternalSQLPkg := false
+			for _, pkg := range sqlPackages {
+				if pkg.packageName == edge.Caller.Func.Pkg.Pkg.Path() {
+					isInternalSQLPkg = true
+					break
+				}
+			}
+			if isInternalSQLPkg {
+				continue
+			}
+
 			cc := edge.Site.Common()
 			args := cc.Args
 			// The first parameter is occasionally the receiver.
@@ -195,7 +269,14 @@ func FindNonConstCalls(cg *callgraph.Graph, qms []*QueryMethod) []ssa.CallInstru
 				panic("arg count mismatch")
 			}
 			v := args[m.Param]
+
 			if _, ok := v.(*ssa.Const); !ok {
+				if inter, ok := v.(*ssa.MakeInterface); ok && types.IsInterface(v.(*ssa.MakeInterface).Type()) {
+					if inter.X.Referrers() == nil || inter.X.Type() != types.Typ[types.String] {
+						continue
+					}
+				}
+
 				bad = append(bad, edge.Site)
 			}
 		}