refactor: naming cleanup and crypto package improvements (#551)

* refactor: naming cleanup across all packages

crypto/pbkdf2_test.go

@@ -0,0 +1,61 @@
+package crypto
+
+import (
+	"crypto/sha1"
+	"encoding/hex"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+// Test vectors from RFC 6070 (PKCS #5 PBKDF2 with HMAC-SHA1).
+// https://www.rfc-editor.org/rfc/rfc6070
+func TestPBKDF2Key_RFC6070(t *testing.T) {
+	tests := []struct {
+		name       string
+		password   string
+		salt       string
+		iterations int
+		keyLen     int
+		want       string
+	}{
+		{
+			name:       "iteration=1",
+			password:   "password",
+			salt:       "salt",
+			iterations: 1,
+			keyLen:     20,
+			want:       "0c60c80f961f0e71f3a9b524af6012062fe037a6",
+		},
+		{
+			name:       "iteration=2",
+			password:   "password",
+			salt:       "salt",
+			iterations: 2,
+			keyLen:     20,
+			want:       "ea6c014dc72d6f8ccd1ed92ace1d41f0d8de8957",
+		},
+		{
+			name:       "iteration=4096",
+			password:   "password",
+			salt:       "salt",
+			iterations: 4096,
+			keyLen:     20,
+			want:       "4b007901b765489abead49d926f721d065a429c1",
+		},
+		{
+			name:       "long_password_and_salt",
+			password:   "passwordPASSWORDpassword",
+			salt:       "saltSALTsaltSALTsaltSALTsaltSALTsalt",
+			iterations: 4096,
+			keyLen:     25,
+			want:       "3d2eec4fe41c849b80c8d83662c0e44a8b291a964cf2f07038",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := PBKDF2Key([]byte(tt.password), []byte(tt.salt), tt.iterations, tt.keyLen, sha1.New)
+			assert.Equal(t, tt.want, hex.EncodeToString(got))
+		})
+	}
+}