Update hash name check to be case insensitive

Some SDPs emit uppercase hash names. This change makes the comparison
case insensitive.

Author: kevmo314

pkg/crypto/fingerprint/hash.go

@@ -3,6 +3,7 @@ package fingerprint
 import (
 	"crypto"
 	"errors"
+	"strings"
 )
 
 var errInvalidHashAlgorithm = errors.New("fingerprint: invalid hash algorithm")
@@ -20,7 +21,7 @@ func nameToHash() map[string]crypto.Hash {
 
 // HashFromString allows looking up a hash algorithm by it's string representation
 func HashFromString(s string) (crypto.Hash, error) {
-	if h, ok := nameToHash()[s]; ok {
+	if h, ok := nameToHash()[strings.ToLower(s)]; ok {
 		return h, nil
 	}
 	return 0, errInvalidHashAlgorithm

pkg/crypto/fingerprint/hash_test.go

@@ -22,6 +22,15 @@ func TestHashFromString(t *testing.T) {
 			t.Errorf("Expected hash ID of %d, got %d", int(crypto.SHA512), int(h))
 		}
 	})
+	t.Run("ValidCaseInsensitiveHashAlgorithm", func(t *testing.T) {
+		h, err := HashFromString("SHA-512")
+		if err != nil {
+			t.Fatalf("Unexpected error for valid hash name, got '%v'", err)
+		}
+		if h != crypto.SHA512 {
+			t.Errorf("Expected hash ID of %d, got %d", int(crypto.SHA512), int(h))
+		}
+	})
 }
 
 func TestStringFromHash_Roundtrip(t *testing.T) {