diff options
Diffstat (limited to 'python/urllib3/contrib/_securetransport')
| -rw-r--r-- | python/urllib3/contrib/_securetransport/__init__.py | 0 | ||||
| -rw-r--r-- | python/urllib3/contrib/_securetransport/bindings.py | 593 | ||||
| -rw-r--r-- | python/urllib3/contrib/_securetransport/low_level.py | 346 |
3 files changed, 939 insertions, 0 deletions
diff --git a/python/urllib3/contrib/_securetransport/__init__.py b/python/urllib3/contrib/_securetransport/__init__.py new file mode 100644 index 0000000..e69de29 --- /dev/null +++ b/python/urllib3/contrib/_securetransport/__init__.py diff --git a/python/urllib3/contrib/_securetransport/bindings.py b/python/urllib3/contrib/_securetransport/bindings.py new file mode 100644 index 0000000..bcf41c0 --- /dev/null +++ b/python/urllib3/contrib/_securetransport/bindings.py @@ -0,0 +1,593 @@ +""" +This module uses ctypes to bind a whole bunch of functions and constants from +SecureTransport. The goal here is to provide the low-level API to +SecureTransport. These are essentially the C-level functions and constants, and +they're pretty gross to work with. + +This code is a bastardised version of the code found in Will Bond's oscrypto +library. An enormous debt is owed to him for blazing this trail for us. For +that reason, this code should be considered to be covered both by urllib3's +license and by oscrypto's: + + Copyright (c) 2015-2016 Will Bond <will@wbond.net> + + Permission is hereby granted, free of charge, to any person obtaining a + copy of this software and associated documentation files (the "Software"), + to deal in the Software without restriction, including without limitation + the rights to use, copy, modify, merge, publish, distribute, sublicense, + and/or sell copies of the Software, and to permit persons to whom the + Software is furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice shall be included in + all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + DEALINGS IN THE SOFTWARE. +""" +from __future__ import absolute_import + +import platform +from ctypes.util import find_library +from ctypes import ( + c_void_p, c_int32, c_char_p, c_size_t, c_byte, c_uint32, c_ulong, c_long, + c_bool +) +from ctypes import CDLL, POINTER, CFUNCTYPE + + +security_path = find_library('Security') +if not security_path: + raise ImportError('The library Security could not be found') + + +core_foundation_path = find_library('CoreFoundation') +if not core_foundation_path: + raise ImportError('The library CoreFoundation could not be found') + + +version = platform.mac_ver()[0] +version_info = tuple(map(int, version.split('.'))) +if version_info < (10, 8): + raise OSError( + 'Only OS X 10.8 and newer are supported, not %s.%s' % ( + version_info[0], version_info[1] + ) + ) + +Security = CDLL(security_path, use_errno=True) +CoreFoundation = CDLL(core_foundation_path, use_errno=True) + +Boolean = c_bool +CFIndex = c_long +CFStringEncoding = c_uint32 +CFData = c_void_p +CFString = c_void_p +CFArray = c_void_p +CFMutableArray = c_void_p +CFDictionary = c_void_p +CFError = c_void_p +CFType = c_void_p +CFTypeID = c_ulong + +CFTypeRef = POINTER(CFType) +CFAllocatorRef = c_void_p + +OSStatus = c_int32 + +CFDataRef = POINTER(CFData) +CFStringRef = POINTER(CFString) +CFArrayRef = POINTER(CFArray) +CFMutableArrayRef = POINTER(CFMutableArray) +CFDictionaryRef = POINTER(CFDictionary) +CFArrayCallBacks = c_void_p +CFDictionaryKeyCallBacks = c_void_p +CFDictionaryValueCallBacks = c_void_p + +SecCertificateRef = POINTER(c_void_p) +SecExternalFormat = c_uint32 +SecExternalItemType = c_uint32 +SecIdentityRef = POINTER(c_void_p) +SecItemImportExportFlags = c_uint32 +SecItemImportExportKeyParameters = c_void_p +SecKeychainRef = POINTER(c_void_p) +SSLProtocol = c_uint32 +SSLCipherSuite = c_uint32 +SSLContextRef = POINTER(c_void_p) +SecTrustRef = POINTER(c_void_p) +SSLConnectionRef = c_uint32 +SecTrustResultType = c_uint32 +SecTrustOptionFlags = c_uint32 +SSLProtocolSide = c_uint32 +SSLConnectionType = c_uint32 +SSLSessionOption = c_uint32 + + +try: + Security.SecItemImport.argtypes = [ + CFDataRef, + CFStringRef, + POINTER(SecExternalFormat), + POINTER(SecExternalItemType), + SecItemImportExportFlags, + POINTER(SecItemImportExportKeyParameters), + SecKeychainRef, + POINTER(CFArrayRef), + ] + Security.SecItemImport.restype = OSStatus + + Security.SecCertificateGetTypeID.argtypes = [] + Security.SecCertificateGetTypeID.restype = CFTypeID + + Security.SecIdentityGetTypeID.argtypes = [] + Security.SecIdentityGetTypeID.restype = CFTypeID + + Security.SecKeyGetTypeID.argtypes = [] + Security.SecKeyGetTypeID.restype = CFTypeID + + Security.SecCertificateCreateWithData.argtypes = [ + CFAllocatorRef, + CFDataRef + ] + Security.SecCertificateCreateWithData.restype = SecCertificateRef + + Security.SecCertificateCopyData.argtypes = [ + SecCertificateRef + ] + Security.SecCertificateCopyData.restype = CFDataRef + + Security.SecCopyErrorMessageString.argtypes = [ + OSStatus, + c_void_p + ] + Security.SecCopyErrorMessageString.restype = CFStringRef + + Security.SecIdentityCreateWithCertificate.argtypes = [ + CFTypeRef, + SecCertificateRef, + POINTER(SecIdentityRef) + ] + Security.SecIdentityCreateWithCertificate.restype = OSStatus + + Security.SecKeychainCreate.argtypes = [ + c_char_p, + c_uint32, + c_void_p, + Boolean, + c_void_p, + POINTER(SecKeychainRef) + ] + Security.SecKeychainCreate.restype = OSStatus + + Security.SecKeychainDelete.argtypes = [ + SecKeychainRef + ] + Security.SecKeychainDelete.restype = OSStatus + + Security.SecPKCS12Import.argtypes = [ + CFDataRef, + CFDictionaryRef, + POINTER(CFArrayRef) + ] + Security.SecPKCS12Import.restype = OSStatus + + SSLReadFunc = CFUNCTYPE(OSStatus, SSLConnectionRef, c_void_p, POINTER(c_size_t)) + SSLWriteFunc = CFUNCTYPE(OSStatus, SSLConnectionRef, POINTER(c_byte), POINTER(c_size_t)) + + Security.SSLSetIOFuncs.argtypes = [ + SSLContextRef, + SSLReadFunc, + SSLWriteFunc + ] + Security.SSLSetIOFuncs.restype = OSStatus + + Security.SSLSetPeerID.argtypes = [ + SSLContextRef, + c_char_p, + c_size_t + ] + Security.SSLSetPeerID.restype = OSStatus + + Security.SSLSetCertificate.argtypes = [ + SSLContextRef, + CFArrayRef + ] + Security.SSLSetCertificate.restype = OSStatus + + Security.SSLSetCertificateAuthorities.argtypes = [ + SSLContextRef, + CFTypeRef, + Boolean + ] + Security.SSLSetCertificateAuthorities.restype = OSStatus + + Security.SSLSetConnection.argtypes = [ + SSLContextRef, + SSLConnectionRef + ] + Security.SSLSetConnection.restype = OSStatus + + Security.SSLSetPeerDomainName.argtypes = [ + SSLContextRef, + c_char_p, + c_size_t + ] + Security.SSLSetPeerDomainName.restype = OSStatus + + Security.SSLHandshake.argtypes = [ + SSLContextRef + ] + Security.SSLHandshake.restype = OSStatus + + Security.SSLRead.argtypes = [ + SSLContextRef, + c_char_p, + c_size_t, + POINTER(c_size_t) + ] + Security.SSLRead.restype = OSStatus + + Security.SSLWrite.argtypes = [ + SSLContextRef, + c_char_p, + c_size_t, + POINTER(c_size_t) + ] + Security.SSLWrite.restype = OSStatus + + Security.SSLClose.argtypes = [ + SSLContextRef + ] + Security.SSLClose.restype = OSStatus + + Security.SSLGetNumberSupportedCiphers.argtypes = [ + SSLContextRef, + POINTER(c_size_t) + ] + Security.SSLGetNumberSupportedCiphers.restype = OSStatus + + Security.SSLGetSupportedCiphers.argtypes = [ + SSLContextRef, + POINTER(SSLCipherSuite), + POINTER(c_size_t) + ] + Security.SSLGetSupportedCiphers.restype = OSStatus + + Security.SSLSetEnabledCiphers.argtypes = [ + SSLContextRef, + POINTER(SSLCipherSuite), + c_size_t + ] + Security.SSLSetEnabledCiphers.restype = OSStatus + + Security.SSLGetNumberEnabledCiphers.argtype = [ + SSLContextRef, + POINTER(c_size_t) + ] + Security.SSLGetNumberEnabledCiphers.restype = OSStatus + + Security.SSLGetEnabledCiphers.argtypes = [ + SSLContextRef, + POINTER(SSLCipherSuite), + POINTER(c_size_t) + ] + Security.SSLGetEnabledCiphers.restype = OSStatus + + Security.SSLGetNegotiatedCipher.argtypes = [ + SSLContextRef, + POINTER(SSLCipherSuite) + ] + Security.SSLGetNegotiatedCipher.restype = OSStatus + + Security.SSLGetNegotiatedProtocolVersion.argtypes = [ + SSLContextRef, + POINTER(SSLProtocol) + ] + Security.SSLGetNegotiatedProtocolVersion.restype = OSStatus + + Security.SSLCopyPeerTrust.argtypes = [ + SSLContextRef, + POINTER(SecTrustRef) + ] + Security.SSLCopyPeerTrust.restype = OSStatus + + Security.SecTrustSetAnchorCertificates.argtypes = [ + SecTrustRef, + CFArrayRef + ] + Security.SecTrustSetAnchorCertificates.restype = OSStatus + + Security.SecTrustSetAnchorCertificatesOnly.argstypes = [ + SecTrustRef, + Boolean + ] + Security.SecTrustSetAnchorCertificatesOnly.restype = OSStatus + + Security.SecTrustEvaluate.argtypes = [ + SecTrustRef, + POINTER(SecTrustResultType) + ] + Security.SecTrustEvaluate.restype = OSStatus + + Security.SecTrustGetCertificateCount.argtypes = [ + SecTrustRef + ] + Security.SecTrustGetCertificateCount.restype = CFIndex + + Security.SecTrustGetCertificateAtIndex.argtypes = [ + SecTrustRef, + CFIndex + ] + Security.SecTrustGetCertificateAtIndex.restype = SecCertificateRef + + Security.SSLCreateContext.argtypes = [ + CFAllocatorRef, + SSLProtocolSide, + SSLConnectionType + ] + Security.SSLCreateContext.restype = SSLContextRef + + Security.SSLSetSessionOption.argtypes = [ + SSLContextRef, + SSLSessionOption, + Boolean + ] + Security.SSLSetSessionOption.restype = OSStatus + + Security.SSLSetProtocolVersionMin.argtypes = [ + SSLContextRef, + SSLProtocol + ] + Security.SSLSetProtocolVersionMin.restype = OSStatus + + Security.SSLSetProtocolVersionMax.argtypes = [ + SSLContextRef, + SSLProtocol + ] + Security.SSLSetProtocolVersionMax.restype = OSStatus + + Security.SecCopyErrorMessageString.argtypes = [ + OSStatus, + c_void_p + ] + Security.SecCopyErrorMessageString.restype = CFStringRef + + Security.SSLReadFunc = SSLReadFunc + Security.SSLWriteFunc = SSLWriteFunc + Security.SSLContextRef = SSLContextRef + Security.SSLProtocol = SSLProtocol + Security.SSLCipherSuite = SSLCipherSuite + Security.SecIdentityRef = SecIdentityRef + Security.SecKeychainRef = SecKeychainRef + Security.SecTrustRef = SecTrustRef + Security.SecTrustResultType = SecTrustResultType + Security.SecExternalFormat = SecExternalFormat + Security.OSStatus = OSStatus + + Security.kSecImportExportPassphrase = CFStringRef.in_dll( + Security, 'kSecImportExportPassphrase' + ) + Security.kSecImportItemIdentity = CFStringRef.in_dll( + Security, 'kSecImportItemIdentity' + ) + + # CoreFoundation time! + CoreFoundation.CFRetain.argtypes = [ + CFTypeRef + ] + CoreFoundation.CFRetain.restype = CFTypeRef + + CoreFoundation.CFRelease.argtypes = [ + CFTypeRef + ] + CoreFoundation.CFRelease.restype = None + + CoreFoundation.CFGetTypeID.argtypes = [ + CFTypeRef + ] + CoreFoundation.CFGetTypeID.restype = CFTypeID + + CoreFoundation.CFStringCreateWithCString.argtypes = [ + CFAllocatorRef, + c_char_p, + CFStringEncoding + ] + CoreFoundation.CFStringCreateWithCString.restype = CFStringRef + + CoreFoundation.CFStringGetCStringPtr.argtypes = [ + CFStringRef, + CFStringEncoding + ] + CoreFoundation.CFStringGetCStringPtr.restype = c_char_p + + CoreFoundation.CFStringGetCString.argtypes = [ + CFStringRef, + c_char_p, + CFIndex, + CFStringEncoding + ] + CoreFoundation.CFStringGetCString.restype = c_bool + + CoreFoundation.CFDataCreate.argtypes = [ + CFAllocatorRef, + c_char_p, + CFIndex + ] + CoreFoundation.CFDataCreate.restype = CFDataRef + + CoreFoundation.CFDataGetLength.argtypes = [ + CFDataRef + ] + CoreFoundation.CFDataGetLength.restype = CFIndex + + CoreFoundation.CFDataGetBytePtr.argtypes = [ + CFDataRef + ] + CoreFoundation.CFDataGetBytePtr.restype = c_void_p + + CoreFoundation.CFDictionaryCreate.argtypes = [ + CFAllocatorRef, + POINTER(CFTypeRef), + POINTER(CFTypeRef), + CFIndex, + CFDictionaryKeyCallBacks, + CFDictionaryValueCallBacks + ] + CoreFoundation.CFDictionaryCreate.restype = CFDictionaryRef + + CoreFoundation.CFDictionaryGetValue.argtypes = [ + CFDictionaryRef, + CFTypeRef + ] + CoreFoundation.CFDictionaryGetValue.restype = CFTypeRef + + CoreFoundation.CFArrayCreate.argtypes = [ + CFAllocatorRef, + POINTER(CFTypeRef), + CFIndex, + CFArrayCallBacks, + ] + CoreFoundation.CFArrayCreate.restype = CFArrayRef + + CoreFoundation.CFArrayCreateMutable.argtypes = [ + CFAllocatorRef, + CFIndex, + CFArrayCallBacks + ] + CoreFoundation.CFArrayCreateMutable.restype = CFMutableArrayRef + + CoreFoundation.CFArrayAppendValue.argtypes = [ + CFMutableArrayRef, + c_void_p + ] + CoreFoundation.CFArrayAppendValue.restype = None + + CoreFoundation.CFArrayGetCount.argtypes = [ + CFArrayRef + ] + CoreFoundation.CFArrayGetCount.restype = CFIndex + + CoreFoundation.CFArrayGetValueAtIndex.argtypes = [ + CFArrayRef, + CFIndex + ] + CoreFoundation.CFArrayGetValueAtIndex.restype = c_void_p + + CoreFoundation.kCFAllocatorDefault = CFAllocatorRef.in_dll( + CoreFoundation, 'kCFAllocatorDefault' + ) + CoreFoundation.kCFTypeArrayCallBacks = c_void_p.in_dll(CoreFoundation, 'kCFTypeArrayCallBacks') + CoreFoundation.kCFTypeDictionaryKeyCallBacks = c_void_p.in_dll( + CoreFoundation, 'kCFTypeDictionaryKeyCallBacks' + ) + CoreFoundation.kCFTypeDictionaryValueCallBacks = c_void_p.in_dll( + CoreFoundation, 'kCFTypeDictionaryValueCallBacks' + ) + + CoreFoundation.CFTypeRef = CFTypeRef + CoreFoundation.CFArrayRef = CFArrayRef + CoreFoundation.CFStringRef = CFStringRef + CoreFoundation.CFDictionaryRef = CFDictionaryRef + +except (AttributeError): + raise ImportError('Error initializing ctypes') + + +class CFConst(object): + """ + A class object that acts as essentially a namespace for CoreFoundation + constants. + """ + kCFStringEncodingUTF8 = CFStringEncoding(0x08000100) + + +class SecurityConst(object): + """ + A class object that acts as essentially a namespace for Security constants. + """ + kSSLSessionOptionBreakOnServerAuth = 0 + + kSSLProtocol2 = 1 + kSSLProtocol3 = 2 + kTLSProtocol1 = 4 + kTLSProtocol11 = 7 + kTLSProtocol12 = 8 + + kSSLClientSide = 1 + kSSLStreamType = 0 + + kSecFormatPEMSequence = 10 + + kSecTrustResultInvalid = 0 + kSecTrustResultProceed = 1 + # This gap is present on purpose: this was kSecTrustResultConfirm, which + # is deprecated. + kSecTrustResultDeny = 3 + kSecTrustResultUnspecified = 4 + kSecTrustResultRecoverableTrustFailure = 5 + kSecTrustResultFatalTrustFailure = 6 + kSecTrustResultOtherError = 7 + + errSSLProtocol = -9800 + errSSLWouldBlock = -9803 + errSSLClosedGraceful = -9805 + errSSLClosedNoNotify = -9816 + errSSLClosedAbort = -9806 + + errSSLXCertChainInvalid = -9807 + errSSLCrypto = -9809 + errSSLInternal = -9810 + errSSLCertExpired = -9814 + errSSLCertNotYetValid = -9815 + errSSLUnknownRootCert = -9812 + errSSLNoRootCert = -9813 + errSSLHostNameMismatch = -9843 + errSSLPeerHandshakeFail = -9824 + errSSLPeerUserCancelled = -9839 + errSSLWeakPeerEphemeralDHKey = -9850 + errSSLServerAuthCompleted = -9841 + errSSLRecordOverflow = -9847 + + errSecVerifyFailed = -67808 + errSecNoTrustSettings = -25263 + errSecItemNotFound = -25300 + errSecInvalidTrustSettings = -25262 + + # Cipher suites. We only pick the ones our default cipher string allows. + TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384 = 0xC02C + TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 = 0xC030 + TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256 = 0xC02B + TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 = 0xC02F + TLS_DHE_DSS_WITH_AES_256_GCM_SHA384 = 0x00A3 + TLS_DHE_RSA_WITH_AES_256_GCM_SHA384 = 0x009F + TLS_DHE_DSS_WITH_AES_128_GCM_SHA256 = 0x00A2 + TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 = 0x009E + TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384 = 0xC024 + TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384 = 0xC028 + TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA = 0xC00A + TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA = 0xC014 + TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 = 0x006B + TLS_DHE_DSS_WITH_AES_256_CBC_SHA256 = 0x006A + TLS_DHE_RSA_WITH_AES_256_CBC_SHA = 0x0039 + TLS_DHE_DSS_WITH_AES_256_CBC_SHA = 0x0038 + TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256 = 0xC023 + TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 = 0xC027 + TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA = 0xC009 + TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA = 0xC013 + TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 = 0x0067 + TLS_DHE_DSS_WITH_AES_128_CBC_SHA256 = 0x0040 + TLS_DHE_RSA_WITH_AES_128_CBC_SHA = 0x0033 + TLS_DHE_DSS_WITH_AES_128_CBC_SHA = 0x0032 + TLS_RSA_WITH_AES_256_GCM_SHA384 = 0x009D + TLS_RSA_WITH_AES_128_GCM_SHA256 = 0x009C + TLS_RSA_WITH_AES_256_CBC_SHA256 = 0x003D + TLS_RSA_WITH_AES_128_CBC_SHA256 = 0x003C + TLS_RSA_WITH_AES_256_CBC_SHA = 0x0035 + TLS_RSA_WITH_AES_128_CBC_SHA = 0x002F + TLS_AES_128_GCM_SHA256 = 0x1301 + TLS_AES_256_GCM_SHA384 = 0x1302 + TLS_CHACHA20_POLY1305_SHA256 = 0x1303 diff --git a/python/urllib3/contrib/_securetransport/low_level.py b/python/urllib3/contrib/_securetransport/low_level.py new file mode 100644 index 0000000..b13cd9e --- /dev/null +++ b/python/urllib3/contrib/_securetransport/low_level.py @@ -0,0 +1,346 @@ +""" +Low-level helpers for the SecureTransport bindings. + +These are Python functions that are not directly related to the high-level APIs +but are necessary to get them to work. They include a whole bunch of low-level +CoreFoundation messing about and memory management. The concerns in this module +are almost entirely about trying to avoid memory leaks and providing +appropriate and useful assistance to the higher-level code. +""" +import base64 +import ctypes +import itertools +import re +import os +import ssl +import tempfile + +from .bindings import Security, CoreFoundation, CFConst + + +# This regular expression is used to grab PEM data out of a PEM bundle. +_PEM_CERTS_RE = re.compile( + b"-----BEGIN CERTIFICATE-----\n(.*?)\n-----END CERTIFICATE-----", re.DOTALL +) + + +def _cf_data_from_bytes(bytestring): + """ + Given a bytestring, create a CFData object from it. This CFData object must + be CFReleased by the caller. + """ + return CoreFoundation.CFDataCreate( + CoreFoundation.kCFAllocatorDefault, bytestring, len(bytestring) + ) + + +def _cf_dictionary_from_tuples(tuples): + """ + Given a list of Python tuples, create an associated CFDictionary. + """ + dictionary_size = len(tuples) + + # We need to get the dictionary keys and values out in the same order. + keys = (t[0] for t in tuples) + values = (t[1] for t in tuples) + cf_keys = (CoreFoundation.CFTypeRef * dictionary_size)(*keys) + cf_values = (CoreFoundation.CFTypeRef * dictionary_size)(*values) + + return CoreFoundation.CFDictionaryCreate( + CoreFoundation.kCFAllocatorDefault, + cf_keys, + cf_values, + dictionary_size, + CoreFoundation.kCFTypeDictionaryKeyCallBacks, + CoreFoundation.kCFTypeDictionaryValueCallBacks, + ) + + +def _cf_string_to_unicode(value): + """ + Creates a Unicode string from a CFString object. Used entirely for error + reporting. + + Yes, it annoys me quite a lot that this function is this complex. + """ + value_as_void_p = ctypes.cast(value, ctypes.POINTER(ctypes.c_void_p)) + + string = CoreFoundation.CFStringGetCStringPtr( + value_as_void_p, + CFConst.kCFStringEncodingUTF8 + ) + if string is None: + buffer = ctypes.create_string_buffer(1024) + result = CoreFoundation.CFStringGetCString( + value_as_void_p, + buffer, + 1024, + CFConst.kCFStringEncodingUTF8 + ) + if not result: + raise OSError('Error copying C string from CFStringRef') + string = buffer.value + if string is not None: + string = string.decode('utf-8') + return string + + +def _assert_no_error(error, exception_class=None): + """ + Checks the return code and throws an exception if there is an error to + report + """ + if error == 0: + return + + cf_error_string = Security.SecCopyErrorMessageString(error, None) + output = _cf_string_to_unicode(cf_error_string) + CoreFoundation.CFRelease(cf_error_string) + + if output is None or output == u'': + output = u'OSStatus %s' % error + + if exception_class is None: + exception_class = ssl.SSLError + + raise exception_class(output) + + +def _cert_array_from_pem(pem_bundle): + """ + Given a bundle of certs in PEM format, turns them into a CFArray of certs + that can be used to validate a cert chain. + """ + # Normalize the PEM bundle's line endings. + pem_bundle = pem_bundle.replace(b"\r\n", b"\n") + + der_certs = [ + base64.b64decode(match.group(1)) + for match in _PEM_CERTS_RE.finditer(pem_bundle) + ] + if not der_certs: + raise ssl.SSLError("No root certificates specified") + + cert_array = CoreFoundation.CFArrayCreateMutable( + CoreFoundation.kCFAllocatorDefault, + 0, + ctypes.byref(CoreFoundation.kCFTypeArrayCallBacks) + ) + if not cert_array: + raise ssl.SSLError("Unable to allocate memory!") + + try: + for der_bytes in der_certs: + certdata = _cf_data_from_bytes(der_bytes) + if not certdata: + raise ssl.SSLError("Unable to allocate memory!") + cert = Security.SecCertificateCreateWithData( + CoreFoundation.kCFAllocatorDefault, certdata + ) + CoreFoundation.CFRelease(certdata) + if not cert: + raise ssl.SSLError("Unable to build cert object!") + + CoreFoundation.CFArrayAppendValue(cert_array, cert) + CoreFoundation.CFRelease(cert) + except Exception: + # We need to free the array before the exception bubbles further. + # We only want to do that if an error occurs: otherwise, the caller + # should free. + CoreFoundation.CFRelease(cert_array) + + return cert_array + + +def _is_cert(item): + """ + Returns True if a given CFTypeRef is a certificate. + """ + expected = Security.SecCertificateGetTypeID() + return CoreFoundation.CFGetTypeID(item) == expected + + +def _is_identity(item): + """ + Returns True if a given CFTypeRef is an identity. + """ + expected = Security.SecIdentityGetTypeID() + return CoreFoundation.CFGetTypeID(item) == expected + + +def _temporary_keychain(): + """ + This function creates a temporary Mac keychain that we can use to work with + credentials. This keychain uses a one-time password and a temporary file to + store the data. We expect to have one keychain per socket. The returned + SecKeychainRef must be freed by the caller, including calling + SecKeychainDelete. + + Returns a tuple of the SecKeychainRef and the path to the temporary + directory that contains it. + """ + # Unfortunately, SecKeychainCreate requires a path to a keychain. This + # means we cannot use mkstemp to use a generic temporary file. Instead, + # we're going to create a temporary directory and a filename to use there. + # This filename will be 8 random bytes expanded into base64. We also need + # some random bytes to password-protect the keychain we're creating, so we + # ask for 40 random bytes. + random_bytes = os.urandom(40) + filename = base64.b16encode(random_bytes[:8]).decode('utf-8') + password = base64.b16encode(random_bytes[8:]) # Must be valid UTF-8 + tempdirectory = tempfile.mkdtemp() + + keychain_path = os.path.join(tempdirectory, filename).encode('utf-8') + + # We now want to create the keychain itself. + keychain = Security.SecKeychainRef() + status = Security.SecKeychainCreate( + keychain_path, + len(password), + password, + False, + None, + ctypes.byref(keychain) + ) + _assert_no_error(status) + + # Having created the keychain, we want to pass it off to the caller. + return keychain, tempdirectory + + +def _load_items_from_file(keychain, path): + """ + Given a single file, loads all the trust objects from it into arrays and + the keychain. + Returns a tuple of lists: the first list is a list of identities, the + second a list of certs. + """ + certificates = [] + identities = [] + result_array = None + + with open(path, 'rb') as f: + raw_filedata = f.read() + + try: + filedata = CoreFoundation.CFDataCreate( + CoreFoundation.kCFAllocatorDefault, + raw_filedata, + len(raw_filedata) + ) + result_array = CoreFoundation.CFArrayRef() + result = Security.SecItemImport( + filedata, # cert data + None, # Filename, leaving it out for now + None, # What the type of the file is, we don't care + None, # what's in the file, we don't care + 0, # import flags + None, # key params, can include passphrase in the future + keychain, # The keychain to insert into + ctypes.byref(result_array) # Results + ) + _assert_no_error(result) + + # A CFArray is not very useful to us as an intermediary + # representation, so we are going to extract the objects we want + # and then free the array. We don't need to keep hold of keys: the + # keychain already has them! + result_count = CoreFoundation.CFArrayGetCount(result_array) + for index in range(result_count): + item = CoreFoundation.CFArrayGetValueAtIndex( + result_array, index + ) + item = ctypes.cast(item, CoreFoundation.CFTypeRef) + + if _is_cert(item): + CoreFoundation.CFRetain(item) + certificates.append(item) + elif _is_identity(item): + CoreFoundation.CFRetain(item) + identities.append(item) + finally: + if result_array: + CoreFoundation.CFRelease(result_array) + + CoreFoundation.CFRelease(filedata) + + return (identities, certificates) + + +def _load_client_cert_chain(keychain, *paths): + """ + Load certificates and maybe keys from a number of files. Has the end goal + of returning a CFArray containing one SecIdentityRef, and then zero or more + SecCertificateRef objects, suitable for use as a client certificate trust + chain. + """ + # Ok, the strategy. + # + # This relies on knowing that macOS will not give you a SecIdentityRef + # unless you have imported a key into a keychain. This is a somewhat + # artificial limitation of macOS (for example, it doesn't necessarily + # affect iOS), but there is nothing inside Security.framework that lets you + # get a SecIdentityRef without having a key in a keychain. + # + # So the policy here is we take all the files and iterate them in order. + # Each one will use SecItemImport to have one or more objects loaded from + # it. We will also point at a keychain that macOS can use to work with the + # private key. + # + # Once we have all the objects, we'll check what we actually have. If we + # already have a SecIdentityRef in hand, fab: we'll use that. Otherwise, + # we'll take the first certificate (which we assume to be our leaf) and + # ask the keychain to give us a SecIdentityRef with that cert's associated + # key. + # + # We'll then return a CFArray containing the trust chain: one + # SecIdentityRef and then zero-or-more SecCertificateRef objects. The + # responsibility for freeing this CFArray will be with the caller. This + # CFArray must remain alive for the entire connection, so in practice it + # will be stored with a single SSLSocket, along with the reference to the + # keychain. + certificates = [] + identities = [] + + # Filter out bad paths. + paths = (path for path in paths if path) + + try: + for file_path in paths: + new_identities, new_certs = _load_items_from_file( + keychain, file_path + ) + identities.extend(new_identities) + certificates.extend(new_certs) + + # Ok, we have everything. The question is: do we have an identity? If + # not, we want to grab one from the first cert we have. + if not identities: + new_identity = Security.SecIdentityRef() + status = Security.SecIdentityCreateWithCertificate( + keychain, + certificates[0], + ctypes.byref(new_identity) + ) + _assert_no_error(status) + identities.append(new_identity) + + # We now want to release the original certificate, as we no longer + # need it. + CoreFoundation.CFRelease(certificates.pop(0)) + + # We now need to build a new CFArray that holds the trust chain. + trust_chain = CoreFoundation.CFArrayCreateMutable( + CoreFoundation.kCFAllocatorDefault, + 0, + ctypes.byref(CoreFoundation.kCFTypeArrayCallBacks), + ) + for item in itertools.chain(identities, certificates): + # ArrayAppendValue does a CFRetain on the item. That's fine, + # because the finally block will release our other refs to them. + CoreFoundation.CFArrayAppendValue(trust_chain, item) + + return trust_chain + finally: + for obj in itertools.chain(identities, certificates): + CoreFoundation.CFRelease(obj) |