From 39430cf8c1f9b7118586b1a1f232168fb2d5730b Mon Sep 17 00:00:00 2001 From: kali Date: Thu, 24 Jan 2013 07:36:51 +0900 Subject: switch dependency to pyopenssl --- src/leap/crypto/certs_gnutls.py | 112 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 src/leap/crypto/certs_gnutls.py (limited to 'src/leap/crypto/certs_gnutls.py') diff --git a/src/leap/crypto/certs_gnutls.py b/src/leap/crypto/certs_gnutls.py new file mode 100644 index 00000000..20c0e043 --- /dev/null +++ b/src/leap/crypto/certs_gnutls.py @@ -0,0 +1,112 @@ +''' +We're using PyOpenSSL now + +import ctypes +from StringIO import StringIO +import socket + +import gnutls.connection +import gnutls.crypto +import gnutls.library + +from leap.util.misc import null_check + + +class BadCertError(Exception): + """raised for malformed certs""" + + +def get_https_cert_from_domain(domain): + """ + @param domain: a domain name to get a certificate from. + """ + 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_cert_from_file(_file): + getcert = lambda f: gnutls.crypto.X509Certificate(f.read()) + if isinstance(_file, str): + with open(_file) as f: + cert = getcert(f) + else: + cert = getcert(_file) + return cert + + +def get_pkey_from_file(_file): + getkey = lambda f: gnutls.crypto.X509PrivateKey(f.read()) + if isinstance(_file, str): + with open(_file) as f: + key = getkey(f) + else: + key = getkey(_file) + return key + + +def can_load_cert_and_pkey(string): + try: + f = StringIO(string) + cert = get_cert_from_file(f) + + f = StringIO(string) + key = get_pkey_from_file(f) + + null_check(cert, 'certificate') + null_check(key, 'private key') + except: + # XXX catch GNUTLSError? + raise BadCertError + else: + return True + +def get_cert_fingerprint(domain=None, filepath=None, + hash_type="SHA256", sep=":"): + """ + @param domain: a domain name to get a fingerprint from + @type domain: str + @param filepath: path to a file containing a PEM file + @type filepath: str + @param hash_type: the hash function to be used in the fingerprint. + must be one of SHA1, SHA224, SHA256, SHA384, SHA512 + @type hash_type: str + @rparam: hex_fpr, a hexadecimal representation of a bytestring + containing the fingerprint. + @rtype: string + """ + if domain: + cert = get_https_cert_from_domain(domain) + 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) + + return hex_fpr +''' -- cgit v1.2.3