Merge pull request #3130 from hosseinsh/improved-csr-support

Improved csr support and EC key_type support

lemur/certificates/models.py

@@ -9,9 +9,10 @@ from datetime import timedelta
 
 import arrow
 from cryptography import x509
-from cryptography.hazmat.primitives.asymmetric import rsa
+from cryptography.hazmat.primitives.asymmetric import rsa, ec
 from flask import current_app
 from idna.core import InvalidCodepoint
+from lemur.common.utils import get_key_type_from_ec_curve
 from sqlalchemy import (
     event,
     Integer,
@@ -302,6 +303,8 @@ class Certificate(db.Model):
             return "RSA{key_size}".format(
                 key_size=self.parsed_cert.public_key().key_size
             )
+        elif isinstance(self.parsed_cert.public_key(), ec.EllipticCurvePublicKey):
+            return get_key_type_from_ec_curve(self.parsed_cert.public_key().curve.name)
 
     @property
     def validity_remaining(self):

lemur/certificates/schemas.py

@@ -148,6 +148,13 @@ class CertificateInputSchema(CertificateCreationSchema):
                 data["extensions"]["subAltNames"]["names"] = []
 
             data["extensions"]["subAltNames"]["names"] = csr_sans
+
+            common_name = cert_utils.get_cn_from_csr(data["csr"])
+            if common_name:
+                data["common_name"] = common_name
+            key_type = cert_utils.get_key_type_from_csr(data["csr"])
+            if key_type:
+                data["key_type"] = key_type
         return missing.convert_validity_years(data)
 
 

lemur/certificates/utils.py

@@ -12,6 +12,8 @@ Utils to parse certificate data.
 from cryptography import x509
 from cryptography.hazmat.backends import default_backend
 from marshmallow.exceptions import ValidationError
+from cryptography.hazmat.primitives.asymmetric import rsa, ec
+from lemur.common.utils import get_key_type_from_ec_curve
 
 
 def get_sans_from_csr(data):
@@ -39,3 +41,45 @@ def get_sans_from_csr(data):
         pass
 
     return sub_alt_names
+
+
+def get_cn_from_csr(data):
+    """
+    Fetches common name (CN) from CSR.
+    Works with any kind of SubjectAlternativeName
+    :param data: PEM-encoded string with CSR
+    :return: the common name
+    """
+    try:
+        request = x509.load_pem_x509_csr(data.encode("utf-8"), default_backend())
+    except Exception:
+        raise ValidationError("CSR presented is not valid.")
+
+    common_name = request.subject.get_attributes_for_oid(x509.NameOID.COMMON_NAME)
+    return common_name[0].value
+
+
+def get_key_type_from_csr(data):
+    """
+    Fetches key_type from CSR.
+    Works with any kind of SubjectAlternativeName
+    :param data: PEM-encoded string with CSR
+    :return: key_type
+    """
+    try:
+        request = x509.load_pem_x509_csr(data.encode("utf-8"), default_backend())
+    except Exception:
+        raise ValidationError("CSR presented is not valid.")
+
+    try:
+        if isinstance(request.public_key(), rsa.RSAPublicKey):
+            return "RSA{key_size}".format(
+                key_size=request.public_key().key_size
+            )
+        elif isinstance(request.public_key(), ec.EllipticCurvePublicKey):
+            return get_key_type_from_ec_curve(request.public_key().curve.name)
+        else:
+            raise Exception("Unsupported key type")
+
+    except NotImplemented:
+        raise NotImplemented()

lemur/common/utils.py

@@ -114,6 +114,39 @@ def get_authority_key(body):
     return authority_key.hex()
 
 
+def get_key_type_from_ec_curve(curve_name):
+    """
+    Give an EC curve name, return the matching key_type.
+
+    :param: curve_name
+    :return: key_type
+    """
+
+    _CURVE_TYPES = {
+        ec.SECP192R1().name: "ECCPRIME192V1",
+        ec.SECP256R1().name: "ECCPRIME256V1",
+        ec.SECP224R1().name: "ECCSECP224R1",
+        ec.SECP384R1().name: "ECCSECP384R1",
+        ec.SECP521R1().name: "ECCSECP521R1",
+        ec.SECP256K1().name: "ECCSECP256K1",
+        ec.SECT163K1().name: "ECCSECT163K1",
+        ec.SECT233K1().name: "ECCSECT233K1",
+        ec.SECT283K1().name: "ECCSECT283K1",
+        ec.SECT409K1().name: "ECCSECT409K1",
+        ec.SECT571K1().name: "ECCSECT571K1",
+        ec.SECT163R2().name: "ECCSECT163R2",
+        ec.SECT233R1().name: "ECCSECT233R1",
+        ec.SECT283R1().name: "ECCSECT283R1",
+        ec.SECT409R1().name: "ECCSECT409R1",
+        ec.SECT571R1().name: "ECCSECT571R2",
+    }
+
+    if curve_name in _CURVE_TYPES.keys():
+        return _CURVE_TYPES[curve_name]
+    else:
+        return None
+
+
 def generate_private_key(key_type):
     """
     Generates a new private key based on key_type.
@@ -128,11 +161,11 @@ def generate_private_key(key_type):
     """
 
     _CURVE_TYPES = {
-        "ECCPRIME192V1": ec.SECP192R1(),
-        "ECCPRIME256V1": ec.SECP256R1(),
-        "ECCSECP192R1": ec.SECP192R1(),
+        "ECCPRIME192V1": ec.SECP192R1(),  # duplicate
+        "ECCPRIME256V1": ec.SECP256R1(),  # duplicate
+        "ECCSECP192R1": ec.SECP192R1(),  # duplicate
         "ECCSECP224R1": ec.SECP224R1(),
-        "ECCSECP256R1": ec.SECP256R1(),
+        "ECCSECP256R1": ec.SECP256R1(),  # duplicate
         "ECCSECP384R1": ec.SECP384R1(),
         "ECCSECP521R1": ec.SECP521R1(),
         "ECCSECP256K1": ec.SECP256K1(),

lemur/static/app/angular/certificates/certificate/options.tpl.html

@@ -20,7 +20,7 @@
                           name="certificate signing request"
                           ng-model="certificate.csr"
                           placeholder="PEM encoded string..." class="form-control"
-                          ng-pattern="/^-----BEGIN CERTIFICATE REQUEST-----/"></textarea>
+                          ng-pattern="/(^-----BEGIN CERTIFICATE REQUEST-----[\S\s]*-----END CERTIFICATE REQUEST-----)|(^-----BEGIN NEW CERTIFICATE REQUEST-----[\S\s]*-----END NEW CERTIFICATE REQUEST-----)/"></textarea>
 
           <p ng-show="trackingForm.csr.$invalid && !trackingForm.csr.$pristine"
              class="help-block">Enter a valid certificate signing request.</p>

lemur/tests/test_utils.py

@@ -11,6 +11,12 @@ from lemur.tests.vectors import (
 )
 
 
+def test_get_key_type_from_ec_curve():
+    from lemur.common.utils import get_key_type_from_ec_curve
+
+    assert get_key_type_from_ec_curve("secp256r1") == "ECCPRIME256V1"
+
+
 def test_generate_private_key():
     from lemur.common.utils import generate_private_key