unit test header handling

diff --git a/deltatar/crypto.py b/deltatar/crypto.py
index 68d0380..ff36690 100755 (executable)
--- a/deltatar/crypto.py
+++ b/deltatar/crypto.py
@@ -51,7 +51,10 @@ from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
 from cryptography.hazmat.backends import default_backend
 
 
-__all__ = [ "aesgcm_enc", "aesgcm_dec" ]
+__all__ = [ "ENCRYPT", "DECRYPT"
+          , "AES_GCM_context"
+          , "hdr_make", "hdr_read", "hdr_write"
+          , "I2N_HDR_SIZE" ]
 
 ###############################################################################
 ## constants
@@ -144,7 +147,6 @@ def hdr_make (hdr):
     buf  = bytearray (I2N_HDR_SIZE)
     bufv = memoryview (buf)
 
-    print(">>>", hdr)
     try:
         struct.pack_into (FMT_I2N_HDR, bufv, 0,
                           I2N_HDR_MAGIC,
@@ -264,7 +266,7 @@ class AES_GCM_context (object):
         self.ctx  = aesgcm_context_create (kind, key, aad, iv)
 
 
-    def encrypt_chunk (self, cnk):
+    def process_chunk (self, cnk):
         if self.ctx is None:
             return False, "no valid encryption context"
         return True, self.ctx.update (cnk)

diff --git a/testing/test_crypto.py b/testing/test_crypto.py
index 9406c9a..51c66d0 100644 (file)
--- a/testing/test_crypto.py
+++ b/testing/test_crypto.py
@@ -1,10 +1,13 @@
 import binascii
 import os
 import pylibscrypt
+import pytest
 import unittest
 
 import deltatar.crypto as crypto
 
+import cryptography
+
 def b(s):
     return s.encode("UTF-8")
 
@@ -38,11 +41,12 @@ class CryptoLayerTest (unittest.TestCase):
         key  = os.urandom (CRYPTO_KEY_SIZE)
         enc = crypto.AES_GCM_context (crypto.ENCRYPT, key, TEST_AES_GCM_AAD)
 
+
     def test_crypto_aes_gcm_enc_tag_retrieve (self):
         NaCl = os.urandom (CRYPTO_NACL_SIZE)
         key  = os.urandom (CRYPTO_KEY_SIZE)
         enc = crypto.AES_GCM_context (crypto.ENCRYPT, key, TEST_AES_GCM_AAD)
-        ok, ct = enc.encrypt_chunk (TEST_PLAINTEXT)
+        ok, ct = enc.process_chunk (TEST_PLAINTEXT)
         if ok is False or ct is None:
             raise "error encrypting chunk [%s]" % TEST_PLAINTEXT
         ok, ct, tag = enc.done ()
@@ -51,11 +55,12 @@ class CryptoLayerTest (unittest.TestCase):
         if not tag:
             raise "no tag received upon completing the encryption"
 
+
     def test_crypto_aes_gcm_enc_tag_size (self):
         NaCl = os.urandom (CRYPTO_NACL_SIZE)
         key  = os.urandom (CRYPTO_KEY_SIZE)
         enc = crypto.AES_GCM_context (crypto.ENCRYPT, key, TEST_AES_GCM_AAD)
-        ok, ct = enc.encrypt_chunk (TEST_PLAINTEXT)
+        ok, ct = enc.process_chunk (TEST_PLAINTEXT)
         if ok is False or ct is None:
             raise "error encrypting chunk [%s]" % TEST_PLAINTEXT
         ok, ct, tag = enc.done ()
@@ -65,11 +70,12 @@ class CryptoLayerTest (unittest.TestCase):
             raise "no tag received upon completing the encryption"
         assert len (tag) == CRYPTO_TAG_SIZE
 
+
     def test_crypto_aes_gcm_enc_chunk_size (self):
         NaCl = os.urandom (CRYPTO_NACL_SIZE)
         key  = os.urandom (CRYPTO_KEY_SIZE)
         enc = crypto.AES_GCM_context (crypto.ENCRYPT, key, TEST_AES_GCM_AAD)
-        ok, ct = enc.encrypt_chunk (TEST_PLAINTEXT)
+        ok, ct = enc.process_chunk (TEST_PLAINTEXT)
         if ok is False or ct is None:
             raise "error encrypting chunk [%s]" % TEST_PLAINTEXT
         assert len (ct) == len (TEST_PLAINTEXT)
@@ -80,3 +86,50 @@ class CryptoLayerTest (unittest.TestCase):
             raise "no tag received upon completing the encryption"
         assert len (ct) == 0
 
+
+    def test_crypto_aes_gcm_dec_simple (self):
+        NaCl = os.urandom (CRYPTO_NACL_SIZE)
+        key  = os.urandom (CRYPTO_KEY_SIZE)
+        enc = crypto.AES_GCM_context (crypto.ENCRYPT, key, TEST_AES_GCM_AAD)
+        iv = enc.iv
+        dec = crypto.AES_GCM_context (crypto.DECRYPT, key, TEST_AES_GCM_AAD, iv = iv)
+        ok, ct = enc.process_chunk (TEST_PLAINTEXT)
+        ok, _, tag = enc.done ()
+        ok, pt = dec.process_chunk (ct)
+        ok, _, _ = dec.done (tag)
+        assert pt == TEST_PLAINTEXT
+
+
+    def test_crypto_aes_gcm_dec_bad_tag (self):
+        NaCl = os.urandom (CRYPTO_NACL_SIZE)
+        key  = os.urandom (CRYPTO_KEY_SIZE)
+        enc = crypto.AES_GCM_context (crypto.ENCRYPT, key, TEST_AES_GCM_AAD)
+        iv = enc.iv
+        dec = crypto.AES_GCM_context (crypto.DECRYPT, key, TEST_AES_GCM_AAD, iv = iv)
+        ok, ct = enc.process_chunk (TEST_PLAINTEXT)
+        ok, _, tag = enc.done ()
+        ok, pt = dec.process_chunk (ct)
+        with pytest.raises (cryptography.exceptions.InvalidTag):
+            tag = tag[1:] + b"X"
+            ok, _, _ = dec.done (tag)
+
+
+    def test_crypto_fmt_hdr_make (self):
+        meta = faux_hdr()
+        ok, hdr = crypto.hdr_make (meta)
+        assert ok
+        assert len (hdr) == crypto.I2N_HDR_SIZE
+
+
+    def test_crypto_fmt_hdr_read (self):
+        meta = faux_hdr()
+        ok, hdr = crypto.hdr_make (meta)
+        assert ok
+        ok, mmeta = crypto.hdr_read (hdr)
+        assert ok
+        for k in meta:
+            if meta [k] != mmeta [k]:
+                raise "header mismatch after reading: expected %r, got %r" \
+                      % (meta [k], mmeta [k])
+
+