Merge pull request #5075 from RasmusWL/crypto

Python: Port py/weak-crypto-key to use type-tracking

python/ql/test/experimental/library-tests/frameworks/crypto/ConceptsTest.ql

@@ -0,0 +1,2 @@
+import python
+import experimental.meta.ConceptsTest

python/ql/test/experimental/library-tests/frameworks/crypto/test_dsa.py

@@ -0,0 +1,41 @@
+# DSA is a public-key algorithm for signing messages.
+# Following example at https://pycryptodome.readthedocs.io/en/latest/src/signature/dsa.html
+
+from Crypto.PublicKey import DSA
+from Crypto.Signature import DSS
+from Crypto.Hash import SHA256
+
+
+private_key = DSA.generate(2048) # $ PublicKeyGeneration keySize=2048
+public_key = private_key.publickey()
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+
+message = b"message"
+
+signer = DSS.new(private_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+signature = signer.sign(hasher)
+
+print("signature={}".format(signature))
+
+print()
+
+verifier = DSS.new(public_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+verifier.verify(hasher, signature)
+print("Signature verified (as expected)")
+
+try:
+    hasher = SHA256.new(b"other message")
+    verifier.verify(hasher, signature)
+    raise Exception("Signature verified (unexpected)")
+except ValueError:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/crypto/test_ec.py

@@ -0,0 +1,38 @@
+from Crypto.PublicKey import ECC
+from Crypto.Signature import DSS
+from Crypto.Hash import SHA256
+
+
+private_key = ECC.generate(curve="P-256") # $ PublicKeyGeneration keySize=256
+public_key = private_key.public_key()
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+
+message = b"message"
+
+signer = DSS.new(private_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+signature = signer.sign(hasher)
+
+print("signature={}".format(signature))
+
+print()
+
+verifier = DSS.new(public_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+verifier.verify(hasher, signature)
+print("Signature verified (as expected)")
+
+try:
+    hasher = SHA256.new(b"other message")
+    verifier.verify(hasher, signature)
+    raise Exception("Signature verified (unexpected)")
+except ValueError:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/crypto/test_rsa.py

@@ -0,0 +1,73 @@
+# RSA is a public-key algorithm for encrypting and signing messages.
+
+from Crypto.PublicKey import RSA
+from Crypto.Cipher import PKCS1_OAEP
+from Crypto.Signature import pss
+from Crypto.Hash import SHA256
+
+private_key = RSA.generate(2048) # $ PublicKeyGeneration keySize=2048
+
+# These 2 methods do the same
+public_key = private_key.publickey()
+public_key = private_key.public_key()
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+print("encrypt/decrypt")
+
+secret_message = b"secret message"
+
+# Following example at https://pycryptodome.readthedocs.io/en/latest/src/examples.html#encrypt-data-with-rsa
+
+encrypt_cipher = PKCS1_OAEP.new(public_key)
+
+encrypted = encrypt_cipher.encrypt(secret_message)
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+decrypt_cipher = PKCS1_OAEP.new(private_key)
+
+decrypted = decrypt_cipher.decrypt(
+    encrypted,
+)
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
+
+print("\n---\n")
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+
+message = b"message"
+
+signer = pss.new(private_key)
+
+hasher = SHA256.new(message)
+signature = signer.sign(hasher)
+
+print("signature={}".format(signature))
+
+print()
+
+
+verifier = pss.new(public_key)
+hasher = SHA256.new(message)
+verifier.verify(hasher, signature)
+print("Signature verified (as expected)")
+
+try:
+    verifier = pss.new(public_key)
+    hasher = SHA256.new(b"other message")
+    verifier.verify(hasher, signature)
+    raise Exception("Signature verified (unexpected)")
+except ValueError:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/cryptodome/ConceptsTest.ql

@@ -0,0 +1,2 @@
+import python
+import experimental.meta.ConceptsTest

python/ql/test/experimental/library-tests/frameworks/cryptodome/test_dsa.py

@@ -0,0 +1,41 @@
+# DSA is a public-key algorithm for signing messages.
+# Following example at https://pycryptodome.readthedocs.io/en/latest/src/signature/dsa.html
+
+from Cryptodome.PublicKey import DSA
+from Cryptodome.Signature import DSS
+from Cryptodome.Hash import SHA256
+
+
+private_key = DSA.generate(2048) # $ PublicKeyGeneration keySize=2048
+public_key = private_key.publickey()
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+
+message = b"message"
+
+signer = DSS.new(private_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+signature = signer.sign(hasher)
+
+print("signature={}".format(signature))
+
+print()
+
+verifier = DSS.new(public_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+verifier.verify(hasher, signature)
+print("Signature verified (as expected)")
+
+try:
+    hasher = SHA256.new(b"other message")
+    verifier.verify(hasher, signature)
+    raise Exception("Signature verified (unexpected)")
+except ValueError:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/cryptodome/test_ec.py

@@ -0,0 +1,38 @@
+from Cryptodome.PublicKey import ECC
+from Cryptodome.Signature import DSS
+from Cryptodome.Hash import SHA256
+
+
+private_key = ECC.generate(curve="P-256") # $ PublicKeyGeneration keySize=256
+public_key = private_key.public_key()
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+
+message = b"message"
+
+signer = DSS.new(private_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+signature = signer.sign(hasher)
+
+print("signature={}".format(signature))
+
+print()
+
+verifier = DSS.new(public_key, mode='fips-186-3')
+
+hasher = SHA256.new(message)
+verifier.verify(hasher, signature)
+print("Signature verified (as expected)")
+
+try:
+    hasher = SHA256.new(b"other message")
+    verifier.verify(hasher, signature)
+    raise Exception("Signature verified (unexpected)")
+except ValueError:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/cryptodome/test_rsa.py

@@ -0,0 +1,73 @@
+# RSA is a public-key algorithm for encrypting and signing messages.
+
+from Cryptodome.PublicKey import RSA
+from Cryptodome.Cipher import PKCS1_OAEP
+from Cryptodome.Signature import pss
+from Cryptodome.Hash import SHA256
+
+private_key = RSA.generate(2048) # $ PublicKeyGeneration keySize=2048
+
+# These 2 methods do the same
+public_key = private_key.publickey()
+public_key = private_key.public_key()
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+print("encrypt/decrypt")
+
+secret_message = b"secret message"
+
+# Following example at https://pycryptodome.readthedocs.io/en/latest/src/examples.html#encrypt-data-with-rsa
+
+encrypt_cipher = PKCS1_OAEP.new(public_key)
+
+encrypted = encrypt_cipher.encrypt(secret_message)
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+decrypt_cipher = PKCS1_OAEP.new(private_key)
+
+decrypted = decrypt_cipher.decrypt(
+    encrypted,
+)
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
+
+print("\n---\n")
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+
+message = b"message"
+
+signer = pss.new(private_key)
+
+hasher = SHA256.new(message)
+signature = signer.sign(hasher)
+
+print("signature={}".format(signature))
+
+print()
+
+verifier = pss.new(public_key)
+
+hasher = SHA256.new(message)
+verifier.verify(hasher, signature)
+print("Signature verified (as expected)")
+
+try:
+    verifier = pss.new(public_key)
+    hasher = SHA256.new(b"other message")
+    verifier.verify(hasher, signature)
+    raise Exception("Signature verified (unexpected)")
+except ValueError:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/cryptography/ConceptsTest.ql

@@ -0,0 +1,2 @@
+import python
+import experimental.meta.ConceptsTest

python/ql/test/experimental/library-tests/frameworks/cryptography/test_dsa.py

@@ -0,0 +1,37 @@
+# DSA is a public-key algorithm for signing messages.
+# see https://cryptography.io/en/latest/hazmat/primitives/asymmetric/dsa.html
+
+from cryptography.hazmat.primitives.asymmetric import dsa
+from cryptography.hazmat.primitives import hashes
+from cryptography.exceptions import InvalidSignature
+
+HASH_ALGORITHM = hashes.SHA256()
+
+private_key = dsa.generate_private_key(key_size=2048) # $ PublicKeyGeneration keySize=2048
+public_key = private_key.public_key()
+
+message = b"message"
+
+# Following example at https://cryptography.io/en/latest/hazmat/primitives/asymmetric/dsa.html#signing
+
+signature = private_key.sign(
+    message,
+    algorithm=HASH_ALGORITHM,
+)
+
+print("signature={}".format(signature))
+
+print()
+
+public_key.verify(
+    signature, message, algorithm=HASH_ALGORITHM
+)
+print("Signature verified (as expected)")
+
+try:
+    public_key.verify(
+        signature, b"other message", algorithm=HASH_ALGORITHM
+    )
+    raise Exception("Signature verified (unexpected)")
+except InvalidSignature:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/cryptography/test_ec.py

@@ -0,0 +1,43 @@
+# see https://cryptography.io/en/latest/hazmat/primitives/asymmetric/rsa.html
+
+from cryptography.hazmat.primitives.asymmetric import ec
+from cryptography.hazmat.primitives import hashes
+from cryptography.exceptions import InvalidSignature
+
+
+private_key = ec.generate_private_key(curve=ec.SECP384R1()) # $ PublicKeyGeneration keySize=384
+public_key = private_key.public_key()
+
+HASH_ALGORITHM = hashes.SHA256()
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+SIGNATURE_ALGORITHM = ec.ECDSA(HASH_ALGORITHM)
+
+message = b"message"
+
+signature = private_key.sign(
+    message,
+    signature_algorithm=SIGNATURE_ALGORITHM,
+)
+
+print("signature={}".format(signature))
+
+print()
+
+public_key.verify(
+    signature, message, signature_algorithm=SIGNATURE_ALGORITHM
+)
+print("Signature verified (as expected)")
+
+try:
+    public_key.verify(
+        signature, b"other message", signature_algorithm=SIGNATURE_ALGORITHM
+    )
+    raise Exception("Signature verified (unexpected)")
+except InvalidSignature:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/library-tests/frameworks/cryptography/test_rsa.py

@@ -0,0 +1,80 @@
+# RSA is a public-key algorithm for encrypting and signing messages.
+# see https://cryptography.io/en/latest/hazmat/primitives/asymmetric/rsa.html
+
+from cryptography.hazmat.primitives.asymmetric import rsa, padding
+from cryptography.hazmat.primitives import hashes
+from cryptography.exceptions import InvalidSignature
+
+
+private_key = rsa.generate_private_key(public_exponent=65537, key_size=2048) # $ PublicKeyGeneration keySize=2048
+public_key = private_key.public_key()
+
+HASH_ALGORITHM = hashes.SHA256()
+
+# ------------------------------------------------------------------------------
+# encrypt/decrypt
+# ------------------------------------------------------------------------------
+
+print("encrypt/decrypt")
+
+ENCRYPT_PADDING = padding.OAEP(
+    mgf=padding.MGF1(algorithm=HASH_ALGORITHM),
+    algorithm=HASH_ALGORITHM,
+    label=None,
+)
+
+
+secret_message = b"secret message"
+
+# Following example at https://cryptography.io/en/latest/hazmat/primitives/asymmetric/rsa.html#encryption
+encrypted = public_key.encrypt(secret_message, padding=ENCRYPT_PADDING)
+
+print("encrypted={}".format(encrypted))
+
+print()
+
+decrypted = private_key.decrypt(
+    encrypted,
+    padding=ENCRYPT_PADDING
+)
+
+print("decrypted={}".format(decrypted))
+assert decrypted == secret_message
+
+print("\n---\n")
+
+# ------------------------------------------------------------------------------
+# sign/verify
+# ------------------------------------------------------------------------------
+
+print("sign/verify")
+
+SIGN_PADDING = padding.PSS(
+    mgf=padding.MGF1(HASH_ALGORITHM),
+    salt_length=padding.PSS.MAX_LENGTH
+)
+
+message = b"message"
+
+signature = private_key.sign(
+    message,
+    padding=SIGN_PADDING,
+    algorithm=HASH_ALGORITHM,
+)
+
+print("signature={}".format(signature))
+
+print()
+
+public_key.verify(
+    signature, message, padding=SIGN_PADDING, algorithm=HASH_ALGORITHM
+)
+print("Signature verified (as expected)")
+
+try:
+    public_key.verify(
+        signature, b"other message", padding=SIGN_PADDING, algorithm=HASH_ALGORITHM
+    )
+    raise Exception("Signature verified (unexpected)")
+except InvalidSignature:
+    print("Signature mismatch (as expected)")

python/ql/test/experimental/meta/ConceptsTest.qll

@@ -319,3 +319,25 @@ class SafeAccessCheckTest extends InlineExpectationsTest {
     )
   }
 }
+
+class PublicKeyGenerationTest extends InlineExpectationsTest {
+  PublicKeyGenerationTest() { this = "PublicKeyGenerationTest" }
+
+  override string getARelevantTag() { result in ["PublicKeyGeneration", "keySize"] }
+
+  override predicate hasActualResult(Location location, string element, string tag, string value) {
+    exists(location.getFile().getRelativePath()) and
+    exists(Cryptography::PublicKey::KeyGeneration keyGen |
+      location = keyGen.getLocation() and
+      (
+        element = keyGen.toString() and
+        value = "" and
+        tag = "PublicKeyGeneration"
+        or
+        element = keyGen.toString() and
+        value = keyGen.getKeySizeWithOrigin(_).toString() and
+        tag = "keySize"
+      )
+    )
+  }
+}

python/ql/test/query-tests/Security/CWE-326/WeakCrypto.expected

@@ -1,8 +0,0 @@
-| weak_crypto.py:67:1:67:30 | ControlFlowNode for dsa_gen_key() | Creation of an DSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
-| weak_crypto.py:68:1:68:28 | ControlFlowNode for ec_gen_key() | Creation of an ECC key uses $@ bits, which is below 224 and considered breakable. | weak_crypto.py:21:11:21:33 | ControlFlowNode for FakeWeakEllipticCurve() | 160 |
-| weak_crypto.py:69:1:69:37 | ControlFlowNode for rsa_gen_key() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
-| weak_crypto.py:71:1:71:39 | ControlFlowNode for dsa_gen_key() | Creation of an DSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
-| weak_crypto.py:72:1:72:34 | ControlFlowNode for ec_gen_key() | Creation of an ECC key uses $@ bits, which is below 224 and considered breakable. | weak_crypto.py:21:11:21:33 | ControlFlowNode for FakeWeakEllipticCurve() | 160 |
-| weak_crypto.py:73:1:73:46 | ControlFlowNode for rsa_gen_key() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
-| weak_crypto.py:75:1:75:22 | ControlFlowNode for Attribute() | Creation of an DSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
-| weak_crypto.py:76:1:76:22 | ControlFlowNode for Attribute() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |

python/ql/test/query-tests/Security/CWE-326/WeakCrypto.qlref

@@ -1 +0,0 @@
-Security/CWE-326/WeakCrypto.ql

python/ql/test/query-tests/Security/CWE-326/WeakCryptoKey.expected

@@ -0,0 +1,9 @@
+| weak_crypto.py:68:1:68:21 | ControlFlowNode for dsa_gen_key() | Creation of an DSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:16:12:16:15 | ControlFlowNode for IntegerLiteral | 1024 |
+| weak_crypto.py:69:1:69:19 | ControlFlowNode for ec_gen_key() | Creation of an ECC key uses $@ bits, which is below 224 and considered breakable. | weak_crypto.py:22:11:22:24 | ControlFlowNode for Attribute() | 163 |
+| weak_crypto.py:70:1:70:28 | ControlFlowNode for rsa_gen_key() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
+| weak_crypto.py:72:1:72:30 | ControlFlowNode for dsa_gen_key() | Creation of an DSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:16:12:16:15 | ControlFlowNode for IntegerLiteral | 1024 |
+| weak_crypto.py:73:1:73:25 | ControlFlowNode for ec_gen_key() | Creation of an ECC key uses $@ bits, which is below 224 and considered breakable. | weak_crypto.py:22:11:22:24 | ControlFlowNode for Attribute() | 163 |
+| weak_crypto.py:74:1:74:37 | ControlFlowNode for rsa_gen_key() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
+| weak_crypto.py:76:1:76:22 | ControlFlowNode for Attribute() | Creation of an DSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:16:12:16:15 | ControlFlowNode for IntegerLiteral | 1024 |
+| weak_crypto.py:77:1:77:22 | ControlFlowNode for Attribute() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |
+| weak_crypto.py:84:12:84:29 | ControlFlowNode for Attribute() | Creation of an RSA key uses $@ bits, which is below 2048 and considered breakable. | weak_crypto.py:12:12:12:15 | ControlFlowNode for IntegerLiteral | 1024 |

python/ql/test/query-tests/Security/CWE-326/WeakCryptoKey.qlref

@@ -0,0 +1 @@
+Security/CWE-326/WeakCryptoKey.ql

python/ql/test/query-tests/Security/CWE-326/options

@@ -1 +0,0 @@
-semmle-extractor-options: -p ../lib/ --max-import-depth=3

python/ql/test/query-tests/Security/CWE-326/test_example.py

@@ -0,0 +1,9 @@
+from Cryptodome.PublicKey import RSA
+
+from weak_crypto import only_used_by_test
+
+def test_example():
+    # This is technically not ok, but since it's in a test, we don't want to alert on it
+    RSA.generate(1024)
+
+    only_used_by_test(1024)

python/ql/test/query-tests/Security/CWE-326/weak_crypto.py

@@ -1,7 +1,7 @@
 from cryptography.hazmat import backends
 from cryptography.hazmat.primitives.asymmetric import ec, dsa, rsa
 
-#Crypto and Cryptodome have same API
+# Crypto and Cryptodome have same API
 if random():
     from Crypto.PublicKey import DSA
     from Crypto.PublicKey import RSA
@@ -12,13 +12,14 @@ else:
 RSA_WEAK = 1024
 RSA_OK = 2048
 RSA_STRONG = 3076
+
+DSA_WEAK = 1024
+DSA_OK = 2048
+DSA_STRONG = 3076
+
 BIG = 10000
 
-class FakeWeakEllipticCurve:
-    name = "fake"
-    key_size = 160
-
-EC_WEAK = FakeWeakEllipticCurve()
+EC_WEAK = ec.SECT163K1()  # has key size of 163
 EC_OK = ec.SECP224R1()
 EC_STRONG = ec.SECP384R1()
 EC_BIG = ec.SECT571R1()
@@ -27,50 +28,68 @@ dsa_gen_key = dsa.generate_private_key
 ec_gen_key = ec.generate_private_key
 rsa_gen_key = rsa.generate_private_key
 
-default = backends.default_backend()
 
-#Strong and OK keys.
 
-dsa_gen_key(key_size=RSA_OK, backend=default)
-dsa_gen_key(key_size=RSA_STRONG, backend=default)
-dsa_gen_key(key_size=BIG, backend=default)
-ec_gen_key(curve=EC_OK, backend=default)
-ec_gen_key(curve=EC_STRONG, backend=default)
-ec_gen_key(curve=EC_BIG, backend=default)
-rsa_gen_key(public_exponent=65537, key_size=RSA_OK, backend=default)
-rsa_gen_key(public_exponent=65537, key_size=RSA_STRONG, backend=default)
-rsa_gen_key(public_exponent=65537, key_size=BIG, backend=default)
+# Strong and OK keys.
+
+dsa_gen_key(key_size=DSA_OK)
+dsa_gen_key(key_size=DSA_STRONG)
+dsa_gen_key(key_size=BIG)
+ec_gen_key(curve=EC_OK)
+ec_gen_key(curve=EC_STRONG)
+ec_gen_key(curve=EC_BIG)
+rsa_gen_key(public_exponent=65537, key_size=RSA_OK)
+rsa_gen_key(public_exponent=65537, key_size=RSA_STRONG)
+rsa_gen_key(public_exponent=65537, key_size=BIG)
 
 DSA.generate(bits=RSA_OK)
 DSA.generate(bits=RSA_STRONG)
 RSA.generate(bits=RSA_OK)
 RSA.generate(bits=RSA_STRONG)
 
-dsa_gen_key(RSA_OK, default)
-dsa_gen_key(RSA_STRONG, default)
-dsa_gen_key(BIG, default)
-ec_gen_key(EC_OK, default)
-ec_gen_key(EC_STRONG, default)
-ec_gen_key(EC_BIG, default)
-rsa_gen_key(65537, RSA_OK, default)
-rsa_gen_key(65537, RSA_STRONG, default)
-rsa_gen_key(65537, BIG, default)
+dsa_gen_key(DSA_OK)
+dsa_gen_key(DSA_STRONG)
+dsa_gen_key(BIG)
+ec_gen_key(EC_OK)
+ec_gen_key(EC_STRONG)
+ec_gen_key(EC_BIG)
+rsa_gen_key(65537, RSA_OK)
+rsa_gen_key(65537, RSA_STRONG)
+rsa_gen_key(65537, BIG)
 
-DSA.generate(RSA_OK)
-DSA.generate(RSA_STRONG)
+DSA.generate(DSA_OK)
+DSA.generate(DSA_STRONG)
 RSA.generate(RSA_OK)
 RSA.generate(RSA_STRONG)
 
 
 # Weak keys
 
-dsa_gen_key(RSA_WEAK, default)
-ec_gen_key(EC_WEAK, default)
-rsa_gen_key(65537, RSA_WEAK, default)
+dsa_gen_key(DSA_WEAK)
+ec_gen_key(EC_WEAK)
+rsa_gen_key(65537, RSA_WEAK)
 
-dsa_gen_key(key_size=RSA_WEAK, default)
-ec_gen_key(curve=EC_WEAK, default)
-rsa_gen_key(65537, key_size=RSA_WEAK, default)
+dsa_gen_key(key_size=DSA_WEAK)
+ec_gen_key(curve=EC_WEAK)
+rsa_gen_key(65537, key_size=RSA_WEAK)
 
-DSA.generate(RSA_WEAK)
+DSA.generate(DSA_WEAK)
 RSA.generate(RSA_WEAK)
+
+# ------------------------------------------------------------------------------
+
+# Through function calls
+
+def make_new_rsa_key_weak(bits):
+    return RSA.generate(bits) # NOT OK
+make_new_rsa_key_weak(RSA_WEAK)
+
+
+def make_new_rsa_key_strong(bits):
+    return RSA.generate(bits) # OK
+make_new_rsa_key_strong(RSA_STRONG)
+
+
+def only_used_by_test(bits):
+    # Although this call will technically not be ok, since it's only used in a test, we don't want to alert on it.
+    return RSA.generate(bits)