openpgp/packet: improve handling of short MPIs for RSA values

MPIs are (supposed to be) stripped of leading zeroes. Avoid passing
such short values into crypto/rsa, even if it currently happens to work.

Change-Id: I5a5f4813b8358e83fcc2deeda1272d2733814542
Reviewed-on: https://go-review.googlesource.com/100844
Reviewed-by: Adam Langley <agl@golang.org>
This commit is contained in:
Filippo Valsorda
2018-03-16 18:01:49 +00:00
parent b4956d363a
commit 374053ea96
4 changed files with 60 additions and 42 deletions
+34 -29
View File
@@ -39,39 +39,44 @@ var encryptedKeyPriv = &PrivateKey{
}
func TestDecryptingEncryptedKey(t *testing.T) {
const encryptedKeyHex = "c18c032a67d68660df41c70104005789d0de26b6a50c985a02a13131ca829c413a35d0e6fa8d6842599252162808ac7439c72151c8c6183e76923fe3299301414d0c25a2f06a2257db3839e7df0ec964773f6e4c4ac7ff3b48c444237166dd46ba8ff443a5410dc670cb486672fdbe7c9dfafb75b4fea83af3a204fe2a7dfa86bd20122b4f3d2646cbeecb8f7be8"
const expectedKeyHex = "d930363f7e0308c333b9618617ea728963d8df993665ae7be1092d4926fd864b"
for i, encryptedKeyHex := range []string{
"c18c032a67d68660df41c70104005789d0de26b6a50c985a02a13131ca829c413a35d0e6fa8d6842599252162808ac7439c72151c8c6183e76923fe3299301414d0c25a2f06a2257db3839e7df0ec964773f6e4c4ac7ff3b48c444237166dd46ba8ff443a5410dc670cb486672fdbe7c9dfafb75b4fea83af3a204fe2a7dfa86bd20122b4f3d2646cbeecb8f7be8",
// MPI can be shorter than the length of the key.
"c18b032a67d68660df41c70103f8e520c52ae9807183c669ce26e772e482dc5d8cf60e6f59316e145be14d2e5221ee69550db1d5618a8cb002a719f1f0b9345bde21536d410ec90ba86cac37748dec7933eb7f9873873b2d61d3321d1cd44535014f6df58f7bc0c7afb5edc38e1a974428997d2f747f9a173bea9ca53079b409517d332df62d805564cffc9be6",
} {
const expectedKeyHex = "d930363f7e0308c333b9618617ea728963d8df993665ae7be1092d4926fd864b"
p, err := Read(readerFromHex(encryptedKeyHex))
if err != nil {
t.Errorf("error from Read: %s", err)
return
}
ek, ok := p.(*EncryptedKey)
if !ok {
t.Errorf("didn't parse an EncryptedKey, got %#v", p)
return
}
p, err := Read(readerFromHex(encryptedKeyHex))
if err != nil {
t.Errorf("#%d: error from Read: %s", i, err)
return
}
ek, ok := p.(*EncryptedKey)
if !ok {
t.Errorf("#%d: didn't parse an EncryptedKey, got %#v", i, p)
return
}
if ek.KeyId != 0x2a67d68660df41c7 || ek.Algo != PubKeyAlgoRSA {
t.Errorf("unexpected EncryptedKey contents: %#v", ek)
return
}
if ek.KeyId != 0x2a67d68660df41c7 || ek.Algo != PubKeyAlgoRSA {
t.Errorf("#%d: unexpected EncryptedKey contents: %#v", i, ek)
return
}
err = ek.Decrypt(encryptedKeyPriv, nil)
if err != nil {
t.Errorf("error from Decrypt: %s", err)
return
}
err = ek.Decrypt(encryptedKeyPriv, nil)
if err != nil {
t.Errorf("#%d: error from Decrypt: %s", i, err)
return
}
if ek.CipherFunc != CipherAES256 {
t.Errorf("unexpected EncryptedKey contents: %#v", ek)
return
}
if ek.CipherFunc != CipherAES256 {
t.Errorf("#%d: unexpected EncryptedKey contents: %#v", i, ek)
return
}
keyHex := fmt.Sprintf("%x", ek.Key)
if keyHex != expectedKeyHex {
t.Errorf("bad key, got %s want %x", keyHex, expectedKeyHex)
keyHex := fmt.Sprintf("%x", ek.Key)
if keyHex != expectedKeyHex {
t.Errorf("#%d: bad key, got %s want %s", i, keyHex, expectedKeyHex)
}
}
}
@@ -121,7 +126,7 @@ func TestEncryptingEncryptedKey(t *testing.T) {
keyHex := fmt.Sprintf("%x", ek.Key)
if keyHex != expectedKeyHex {
t.Errorf("bad key, got %s want %x", keyHex, expectedKeyHex)
t.Errorf("bad key, got %s want %s", keyHex, expectedKeyHex)
}
}