feat(builders): add dependency hashing for ant

builders/ant/ant.go

@@ -14,6 +14,7 @@ import (
 	"github.com/bmatcuk/doublestar"
 	"github.com/gnewton/jargo"
 
+	"github.com/fossas/fossa-cli/builders/builderutil"
 	"github.com/fossas/fossa-cli/builders/maven"
 	"github.com/fossas/fossa-cli/exec"
 	"github.com/fossas/fossa-cli/files"
@@ -94,8 +95,10 @@ func (builder *AntBuilder) Analyze(m module.Module, allowUnresolved bool) ([]mod
 	for _, jarFilePath := range jarFilePaths {
 		locator, err := locatorFromJar(jarFilePath)
 		if err == nil {
+			hashes, _ := builderutil.GetHashes(jarFilePath)
 			dependencies = append(dependencies, module.Dependency{
 				Locator: locator,
+				Hashes:  hashes,
 			})
 		} else {
 			log.Logger.Warningf("unable to resolve Jar: %s", jarFilePath)

builders/builderutil/hashes.go

@@ -0,0 +1,42 @@
+package builderutil
+
+import (
+	"crypto/md5"
+	"crypto/sha1"
+	"crypto/sha256"
+	"io"
+	"os"
+
+	"github.com/fossas/fossa-cli/module"
+)
+
+// GetHashes computes checksums of a variety of types for a given file path
+func GetHashes(path string) (module.Hashes, error) {
+	hashes := module.Hashes{}
+
+	f, err := os.Open(path)
+	if err != nil {
+		return hashes, err
+	}
+	defer f.Close()
+
+	sha1Hash := sha1.New()
+	if _, err := io.Copy(sha1Hash, f); err != nil {
+		return hashes, err
+	}
+	hashes.SHA1 = string(sha1Hash.Sum(nil))
+
+	md5Hash := md5.New()
+	if _, err := io.Copy(md5Hash, f); err != nil {
+		return hashes, err
+	}
+	hashes.MD5 = string(md5Hash.Sum(nil))
+
+	sha256Hash := sha256.New()
+	if _, err := io.Copy(sha256Hash, f); err != nil {
+		return hashes, err
+	}
+	hashes.SHA256 = string(sha256Hash.Sum(nil))
+
+	return hashes, err
+}