Follow COSE-HPKE early version of draft-03.

dajiaji · Oct 31, 2022 · c801485 · c801485
1 parent 6565c79
commit c801485
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Showing 5 changed files with 39 additions and 39 deletions.
diff --git a/README.md b/README.md
@@ -397,8 +397,8 @@ encoded = sender.encode_and_encrypt(
         4: b"01",  # kid: "01"
         -4: {  # HPKE sender information
             1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-            5: 0x0001,  # kdf: HKDF-SHA256
-            2: 0x0001,  # aead: AES-128-GCM
+            2: 0x0001,  # kdf: HKDF-SHA256
+            3: 0x0001,  # aead: AES-128-GCM
         },
     },
 )
@@ -640,8 +640,8 @@ r = Recipient.new(
         4: b"01",  # kid: "01"
         -4: {  # HPKE sender information
             1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-            5: 0x0001,  # kdf: HKDF-SHA256
-            2: 0x0001,  # aead: AES-128-GCM
+            2: 0x0001,  # kdf: HKDF-SHA256
+            3: 0x0001,  # aead: AES-128-GCM
         },
     },
 )

diff --git a/cwt/recipient_algs/hpke.py b/cwt/recipient_algs/hpke.py
@@ -21,11 +21,11 @@ def __init__(
             raise ValueError("HPKE sender information(-4) not found.")
         if 1 not in unprotected[-4]:
             raise ValueError("kem id(1) not found in HPKE sender information(-4).")
-        if 5 not in unprotected[-4]:
-            raise ValueError("kdf id(5) not found in HPKE sender information(-4).")
         if 2 not in unprotected[-4]:
-            raise ValueError("aead id(2) not found in HPKE sender information(-4).")
-        self._suite = HPKECipherSuite(unprotected[-4][1], unprotected[-4][5], unprotected[-4][2])
+            raise ValueError("kdf id(2) not found in HPKE sender information(-4).")
+        if 3 not in unprotected[-4]:
+            raise ValueError("aead id(3) not found in HPKE sender information(-4).")
+        self._suite = HPKECipherSuite(unprotected[-4][1], unprotected[-4][2], unprotected[-4][3])
         return
 
     def apply(
@@ -45,7 +45,7 @@ def to_list(self, payload: bytes = b"", external_aad: bytes = b"", aad_context:
         enc_structure = [aad_context, self._dumps(self._protected), external_aad]
         aad = self._dumps(enc_structure)
         enc, self._ciphertext = self._recipient_key.seal(self._suite, payload, aad)
-        self._unprotected[-4][3] = enc
+        self._unprotected[-4][4] = enc
         return super().to_list(payload, external_aad, aad_context)
 
     def decrypt(
@@ -61,4 +61,4 @@ def decrypt(
     ) -> bytes:
         enc_structure = [aad_context, self._dumps(self._protected), external_aad]
         aad = self._dumps(enc_structure)
-        return key.open(self._suite, self._unprotected[-4][3], self._ciphertext, aad)
+        return key.open(self._suite, self._unprotected[-4][4], self._ciphertext, aad)
diff --git a/tests/test_cose_sample.py b/tests/test_cose_sample.py
@@ -354,8 +354,8 @@ def test_cose_usage_examples_cose_encrypt0_hpke(self):
                 4: b"01",  # kid: "01"
                 -4: {  # HPKE sender information
                     1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-                    5: 0x0001,  # kdf: HKDF-SHA256
-                    2: 0x0001,  # aead: AES-128-GCM
+                    2: 0x0001,  # kdf: HKDF-SHA256
+                    3: 0x0001,  # aead: AES-128-GCM
                 },
             },
         )
@@ -438,8 +438,8 @@ def test_cose_usage_examples_cose_encrypt_hpke(self):
                 4: b"01",  # kid: "01"
                 -4: {  # HPKE sender information
                     1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-                    5: 0x0001,  # kdf: HKDF-SHA256
-                    2: 0x0001,  # aead: AES-128-GCM
+                    2: 0x0001,  # kdf: HKDF-SHA256
+                    3: 0x0001,  # aead: AES-128-GCM
                 },
             },
         )
@@ -486,8 +486,8 @@ def test_cose_usage_examples_cose_encrypt_hpke_with_1st_layer_hpke(self):
                 4: b"01",  # kid: "01"
                 -4: {  # HPKE sender information
                     1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-                    5: 0x0001,  # kdf: HKDF-SHA256
-                    2: 0x0001,  # aead: AES-128-GCM
+                    2: 0x0001,  # kdf: HKDF-SHA256
+                    3: 0x0001,  # aead: AES-128-GCM
                 },
             },
         )
@@ -503,8 +503,8 @@ def test_cose_usage_examples_cose_encrypt_hpke_with_1st_layer_hpke(self):
                     4: b"xx",  # kid: "xx"
                     -4: {  # HPKE sender information
                         1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-                        5: 0x0001,  # kdf: HKDF-SHA256
-                        2: 0x0001,  # aead: AES-128-GCM
+                        2: 0x0001,  # kdf: HKDF-SHA256
+                        3: 0x0001,  # aead: AES-128-GCM
                     },
                 },
                 recipients=[r],
@@ -532,8 +532,8 @@ def test_cose_usage_examples_cose_encrypt_hpke_with_nonce(self):
                 4: b"01",  # kid: "01"
                 -4: {  # HPKE sender information
                     1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-                    5: 0x0001,  # kdf: HKDF-SHA256
-                    2: 0x0001,  # aead: AES-128-GCM
+                    2: 0x0001,  # kdf: HKDF-SHA256
+                    3: 0x0001,  # aead: AES-128-GCM
                 },
             },
         )
@@ -549,8 +549,8 @@ def test_cose_usage_examples_cose_encrypt_hpke_with_nonce(self):
                     4: b"xx",  # kid: "xx"
                     -4: {  # HPKE sender information
                         1: 0x0010,  # kem: DHKEM(P-256, HKDF-SHA256)
-                        5: 0x0001,  # kdf: HKDF-SHA256
-                        2: 0x0001,  # aead: AES-128-GCM
+                        2: 0x0001,  # kdf: HKDF-SHA256
+                        3: 0x0001,  # aead: AES-128-GCM
                     },
                 },
                 recipients=[r],

diff --git a/tests/test_recipient.py b/tests/test_recipient.py
@@ -634,7 +634,7 @@ def test_recipients_from_list_with_invalid_args(self, invalid, msg):
         assert msg in str(err.value)
 
     def test_recipients_open_without_key(self):
-        r = RecipientInterface(protected={1: -1}, unprotected={4: b"01", -4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        r = RecipientInterface(protected={1: -1}, unprotected={4: b"01", -4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         rs = Recipients([r])
         with pytest.raises(ValueError) as err:
             rs.decrypt([])
@@ -649,7 +649,7 @@ def test_recipients_open_with_empty_recipients(self, rsk1):
         assert "No recipients." in str(err.value)
 
     def test_recipients_open_with_rpk_without_kid(self, rsk1, rsk2):
-        r = Recipient.new(protected={1: -1}, unprotected={-4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        r = Recipient.new(protected={1: -1}, unprotected={-4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         rpk = COSEKey.from_jwk(
             {
                 "kty": "EC",
@@ -672,7 +672,7 @@ def test_recipients_open_with_rpk_without_kid(self, rsk1, rsk2):
         assert b"This is the content." == recipient.decode(encoded, [rsk1, rsk2])
 
     def test_recipients_open_with_verify_kid_and_rpk_without_kid(self, rsk1, rsk2):
-        r = Recipient.new(protected={1: -1}, unprotected={-4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        r = Recipient.new(protected={1: -1}, unprotected={-4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         rpk = COSEKey.from_jwk(
             {
                 "kty": "EC",
@@ -698,7 +698,7 @@ def test_recipients_open_with_verify_kid_and_rpk_without_kid(self, rsk1, rsk2):
         assert "kid should be specified in recipient." in str(err.value)
 
     def test_recipients_open_failed_with_rpk_without_kid(self, rsk1):
-        r = Recipient.new(protected={1: -1}, unprotected={-4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        r = Recipient.new(protected={1: -1}, unprotected={-4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         rpk = COSEKey.from_jwk(
             {
                 "kty": "EC",
@@ -724,7 +724,7 @@ def test_recipients_open_failed_with_rpk_without_kid(self, rsk1):
         assert "Failed to decrypt." in str(err.value)
 
     def test_recipients_open_with_multiple_rsks(self, rpk2, rsk1, rsk2):
-        r = Recipient.new(protected={1: -1}, unprotected={4: b"02", -4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        r = Recipient.new(protected={1: -1}, unprotected={4: b"02", -4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         r.apply(recipient_key=rpk2)
         sender = COSE.new()
         encoded = sender.encode_and_encrypt(
@@ -738,7 +738,7 @@ def test_recipients_open_with_multiple_rsks(self, rpk2, rsk1, rsk2):
         assert b"This is the content." == recipient.decode(encoded, [rsk1, rsk2])
 
     def test_recipients_open_with_invalid_rsk(self, rpk1):
-        r = Recipient.new(protected={1: -1}, unprotected={4: b"02", -4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        r = Recipient.new(protected={1: -1}, unprotected={4: b"02", -4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         r.apply(recipient_key=rpk1)
         sender = COSE.new()
         encoded = sender.encode_and_encrypt(

diff --git a/tests/test_recipient_algs_hpke.py b/tests/test_recipient_algs_hpke.py
@@ -13,20 +13,20 @@ class TestHPKE:
     """
 
     def test_recipient_algs_hpke(self):
-        ctx = HPKE({1: -1}, {-4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        ctx = HPKE({1: -1}, {-4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         assert isinstance(ctx, HPKE)
         assert ctx.alg == -1
 
     def test_recipient_algs_hpke_apply_without_recipient_key(self):
-        ctx = HPKE({1: -1}, {-4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+        ctx = HPKE({1: -1}, {-4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
         with pytest.raises(ValueError) as err:
             ctx.apply()
             pytest.fail("apply should fail.")
         assert "recipient_key should be set." in str(err.value)
 
     def test_recipient_algs_hpke_without_alg(self):
         with pytest.raises(ValueError) as err:
-            HPKE({1: 1}, {-4: {1: 0x0010, 5: 0x0001, 2: 0x0001}})
+            HPKE({1: 1}, {-4: {1: 0x0010, 2: 0x0001, 3: 0x0001}})
             pytest.fail("HPKE should fail.")
         assert "alg should be HPKE(-1)." in str(err.value)
 
@@ -38,27 +38,27 @@ def test_recipient_algs_hpke_without_alg(self):
                 "HPKE sender information(-4) not found.",
             ),
             (
-                {-4: {5: 0x0001, 2: 0x0001}},
+                {-4: {2: 0x0001, 3: 0x0001}},
                 "kem id(1) not found in HPKE sender information(-4).",
             ),
             (
-                {-4: {1: 0x0010, 2: 0x0001}},
-                "kdf id(5) not found in HPKE sender information(-4).",
+                {-4: {1: 0x0010, 3: 0x0001}},
+                "kdf id(2) not found in HPKE sender information(-4).",
             ),
             (
-                {-4: {1: 0x0010, 5: 0x0001}},
-                "aead id(2) not found in HPKE sender information(-4).",
+                {-4: {1: 0x0010, 2: 0x0001}},
+                "aead id(3) not found in HPKE sender information(-4).",
             ),
             (
-                {-4: {1: 0xFFFF, 5: 0x0001, 2: 0x0001}},
+                {-4: {1: 0xFFFF, 2: 0x0001, 3: 0x0001}},
                 "Unsupported or unknown KEM id: 65535.",
             ),
             (
-                {-4: {1: 0x0010, 5: 0xFFFF, 2: 0x0001}},
+                {-4: {1: 0x0010, 2: 0xFFFF, 3: 0x0001}},
                 "Unsupported or unknown KDF id: 65535.",
             ),
             (
-                {-4: {1: 0x0010, 5: 0x0001, 2: 0xFFFF}},
+                {-4: {1: 0x0010, 2: 0x0001, 3: 0xFFFF}},
                 "Unsupported or unknown AEAD id: 65535.",
             ),
         ],