switch dependency to pyopenssl

1 files changed, 38 insertions, 48 deletions

diff --git a/src/leap/crypto/certs.py b/src/leap/crypto/certs.py
index 78f49fb0..c2835878 100644
--- a/src/leap/crypto/certs.py
+++ b/src/leap/crypto/certs.py
@@ -1,44 +1,53 @@
-import ctypes
+import logging
+import os
 from StringIO import StringIO
-import socket
+import ssl
 
-import gnutls.connection
-import gnutls.crypto
-import gnutls.library
+from OpenSSL import crypto
 
 from leap.util.misc import null_check
 
+logger = logging.getLogger(__name__)
+
 
 class BadCertError(Exception):
-    """raised for malformed certs"""
+    """
+    raised for malformed certs
+    """
 
 
-def get_https_cert_from_domain(domain):
+class NoCertError(Exception):
     """
-    @param domain: a domain name to get a certificate from.
+    raised for cert not found in given path
     """
-    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-    cred = gnutls.connection.X509Credentials()
 
-    session = gnutls.connection.ClientSession(sock, cred)
-    session.connect((domain, 443))
-    session.handshake()
-    cert = session.peer_certificate
-    return cert
+
+def get_https_cert_from_domain(domain, port=443):
+    """
+    @param domain: a domain name to get a certificate from.
+    """
+    cert = ssl.get_server_certificate((domain, port))
+    x509 = crypto.load_certificate(crypto.FILETYPE_PEM, cert)
+    return x509
 
 
 def get_cert_from_file(_file):
-    getcert = lambda f: gnutls.crypto.X509Certificate(f.read())
+    null_check(_file, "pem file")
     if isinstance(_file, str):
+        if not os.path.isfile(_file):
+            raise NoCertError
         with open(_file) as f:
-            cert = getcert(f)
+            cert = f.read()
     else:
-        cert = getcert(_file)
-    return cert
+        cert = _file.read()
+    x509 = crypto.load_certificate(crypto.FILETYPE_PEM, cert)
+    return x509
 
 
 def get_pkey_from_file(_file):
-    getkey = lambda f: gnutls.crypto.X509PrivateKey(f.read())
+    getkey = lambda f: crypto.load_privatekey(
+        crypto.FILETYPE_PEM, f.read())
+
     if isinstance(_file, str):
         with open(_file) as f:
             key = getkey(f)
@@ -48,6 +57,10 @@ def get_pkey_from_file(_file):
 
 
 def can_load_cert_and_pkey(string):
+    """
+    loads certificate and private key from
+    a buffer
+    """
     try:
         f = StringIO(string)
         cert = get_cert_from_file(f)
@@ -57,14 +70,14 @@ def can_load_cert_and_pkey(string):
 
         null_check(cert, 'certificate')
         null_check(key, 'private key')
-    except:
-        # XXX catch GNUTLSError?
+    except Exception as exc:
+        logger.error(type(exc), exc.message)
         raise BadCertError
     else:
         return True
 
 
-def get_cert_fingerprint(domain=None, filepath=None,
+def get_cert_fingerprint(domain=None, port=443, filepath=None,
                          hash_type="SHA256", sep=":"):
     """
     @param domain: a domain name to get a fingerprint from
@@ -79,31 +92,8 @@ def get_cert_fingerprint(domain=None, filepath=None,
     @rtype: string
     """
     if domain:
-        cert = get_https_cert_from_domain(domain)
+        cert = get_https_cert_from_domain(domain, port=port)
     if filepath:
         cert = get_cert_from_file(filepath)
-
-    _buffer = ctypes.create_string_buffer(64)
-    buffer_length = ctypes.c_size_t(64)
-
-    SUPPORTED_DIGEST_FUN = ("SHA1", "SHA224", "SHA256", "SHA384", "SHA512")
-    if hash_type in SUPPORTED_DIGEST_FUN:
-        digestfunction = getattr(
-            gnutls.library.constants,
-            "GNUTLS_DIG_%s" % hash_type)
-    else:
-        # XXX improperlyconfigured or something
-        raise Exception("digest function not supported")
-
-    gnutls.library.functions.gnutls_x509_crt_get_fingerprint(
-        cert._c_object, digestfunction,
-        ctypes.byref(_buffer), ctypes.byref(buffer_length))
-
-    # deinit
-    #server_cert._X509Certificate__deinit(server_cert._c_object)
-    # needed? is segfaulting
-
-    fpr = ctypes.string_at(_buffer, buffer_length.value)
-    hex_fpr = sep.join(u"%02X" % ord(char) for char in fpr)
-
+    hex_fpr = cert.digest(hash_type)
     return hex_fpr