summaryrefslogtreecommitdiff
path: root/internal/siv_aead
diff options
context:
space:
mode:
authorJakob Unterwurzacher2016-10-03 23:58:19 +0200
committerJakob Unterwurzacher2016-10-03 23:58:19 +0200
commit46018785b41cac7cfd79174e7f7ca41443a7231a (patch)
tree3fd23841bea3d1c011a1c3110701db12cc715540 /internal/siv_aead
parentb7be386e463e67133069036141655fb2b2035047 (diff)
siv_aead: Overhead is always 16
Add a test for that. Also test operations using a 64-byte key.
Diffstat (limited to 'internal/siv_aead')
-rw-r--r--internal/siv_aead/correctness_test.go84
-rw-r--r--internal/siv_aead/siv_aead.go6
2 files changed, 84 insertions, 6 deletions
diff --git a/internal/siv_aead/correctness_test.go b/internal/siv_aead/correctness_test.go
index c271970..a9885e7 100644
--- a/internal/siv_aead/correctness_test.go
+++ b/internal/siv_aead/correctness_test.go
@@ -8,7 +8,31 @@ import (
"github.com/jacobsa/crypto/siv"
)
-func TestAll(t *testing.T) {
+// Test all supported key lengths
+func TestKeyLens(t *testing.T) {
+ keyLens := []int{32, 48, 64}
+ nonce := make([]byte, 16)
+ plaintext := []byte("foobar")
+ for _, keyLen := range keyLens {
+ key := make([]byte, keyLen)
+ a := New(key)
+ ciphertext2 := a.Seal(nil, nonce, plaintext, nil)
+
+ ciphertext, err := siv.Encrypt(nil, key, plaintext, [][]byte{nil, nonce})
+ if err != nil {
+ t.Error(err)
+ } else if o := len(ciphertext) - len(plaintext); o != a.Overhead() {
+ t.Errorf("keyLen=%d, actual overhead: %d\n", keyLen, o)
+ }
+ if !bytes.Equal(ciphertext, ciphertext2) {
+ t.Errorf("siv and siv_aead produce different results")
+ }
+ }
+
+}
+
+// Test using a 32-byte key
+func TestK32(t *testing.T) {
key := bytes.Repeat([]byte{1}, 32)
nonce := bytes.Repeat([]byte{2}, 16)
plaintext := []byte{1, 2, 3, 4, 5, 6, 7, 8, 9}
@@ -64,3 +88,61 @@ func TestAll(t *testing.T) {
t.Error("should have failed")
}
}
+
+// Test using a 64-byte key
+func TestK64(t *testing.T) {
+ key := bytes.Repeat([]byte{1}, 64)
+ nonce := bytes.Repeat([]byte{2}, 16)
+ plaintext := []byte{1, 2, 3, 4, 5, 6, 7, 8, 9}
+ aData := make([]byte, 24)
+ // Compare siv and siv_aead results
+ sResult, err := siv.Encrypt(nonce, key, plaintext, [][]byte{aData, nonce})
+ if err != nil {
+ t.Fatal(err)
+ }
+ a := New(key)
+ aResult := a.Seal(nonce, nonce, plaintext, aData)
+ if !bytes.Equal(sResult, aResult) {
+ t.Errorf("siv and siv_aead produce different results")
+ }
+ expectedResult, _ := hex.DecodeString(
+ "02020202020202020202020202020202317b316f67c3ad336c01c9a01b4c5e552ba89e966bc4c1ade1")
+ if !bytes.Equal(aResult, expectedResult) {
+ t.Errorf(hex.EncodeToString(aResult))
+ }
+ // Verify overhead
+ overhead := len(aResult) - len(plaintext) - len(nonce)
+ if overhead != a.Overhead() {
+ t.Errorf("Overhead() returns a wrong value")
+ }
+ // Decrypt
+ p1, err := a.Open(nil, aResult[:16], aResult[16:], aData)
+ if err != nil {
+ t.Error(err)
+ }
+ if !bytes.Equal(plaintext, p1) {
+ t.Errorf("wrong plaintext")
+ }
+ // Decrypt and append
+ dst := []byte{0xaa, 0xbb, 0xcc}
+ p2, err := a.Open(dst, aResult[:16], aResult[16:], aData)
+ if err != nil {
+ t.Error(err)
+ }
+ p2e := append(dst, plaintext...)
+ if !bytes.Equal(p2e, p2) {
+ t.Errorf("wrong plaintext: %s", hex.EncodeToString(p2))
+ }
+ // Decrypt corrupt
+ aResult[17] = 0
+ _, err = a.Open(nil, aResult[:16], aResult[16:], aData)
+ if err == nil {
+ t.Error("should have failed")
+ }
+ // Decrypt and append corrupt
+ aResult[17] = 0
+ _, err = a.Open(dst, aResult[:16], aResult[16:], aData)
+ if err == nil {
+ t.Error("should have failed")
+ }
+}
diff --git a/internal/siv_aead/siv_aead.go b/internal/siv_aead/siv_aead.go
index 21106a5..a0ed882 100644
--- a/internal/siv_aead/siv_aead.go
+++ b/internal/siv_aead/siv_aead.go
@@ -22,11 +22,7 @@ func (s *sivAead) NonceSize() int {
}
func (s *sivAead) Overhead() int {
- // RFC5297:
- // [...] the key length used by AES in CTR and S2V is len(K)/2 and will
- // each be either 128 bits, 192 bits, or 256 bits.
- return len(s.key) / 2
-
+ return 16
}
// Seal - encrypt "in" using "nonce" and "authData" and append the result to "dst"