socketfromfd: fix cross platform usage

on osx and maybe some other systems, SO_PROTOCOL is not set, also
the socket family is not detected correctly.

This patch remove default values in socketfromfd and do the following:
* detect proper family using getsockname instead of getsocktopt
* if no type is given, default to SOCK_STREAM (we don't have any other type)
* if no protocol is given, default to 0 and let the system take care of it.
This commit is contained in:
benoitc 2019-11-25 11:53:02 +01:00
parent fa32aa7757
commit 883e62da46

View File

@ -16,10 +16,6 @@ from .util import find_library
__all__ = ('fromfd',)
SO_DOMAIN = getattr(socket, 'SO_DOMAIN', 39)
SO_TYPE = getattr(socket, 'SO_TYPE', 3)
SO_PROTOCOL = getattr(socket, 'SO_PROTOCOL', 38)
_libc_name = find_library('c')
if _libc_name is not None:
if sys.platform.startswith("aix"):
@ -47,8 +43,12 @@ def _errcheck_errno(result, func, arguments):
if platform.system() == 'SunOS':
_libc_getsockopt = libc._so_getsockopt
_libc_getsockname = libc._so_getsockname
else:
_libc_getsockopt = libc.getsockopt
_libc_getsockname = libc.getsockname
_libc_getsockopt.argtypes = [
ctypes.c_int, # int sockfd
ctypes.c_int, # int level
@ -59,6 +59,17 @@ _libc_getsockopt.argtypes = [
_libc_getsockopt.restype = ctypes.c_int # 0: ok, -1: err
_libc_getsockopt.errcheck = _errcheck_errno
class SockAddr(ctypes.Structure):
_fields_ = [
('sa_len', ctypes.c_uint8),
('sa_family', ctypes.c_uint8),
('sa_data', ctypes.c_char * 14)
]
_libc_getsockname.argtypes = [
ctypes.c_int,
ctypes.POINTER(SockAddr),
ctypes.POINTER(ctypes.c_int)
]
def _raw_getsockopt(fd, level, optname):
"""Make raw getsockopt() call for int32 optval
@ -74,6 +85,11 @@ def _raw_getsockopt(fd, level, optname):
ctypes.byref(optval), ctypes.byref(optlen))
return optval.value
def _raw_getsockname(fd):
sockaddr = SockAddr()
len = ctypes.c_int(ctypes.sizeof(sockaddr))
_libc_getsockname(fd, sockaddr, len)
return sockaddr.sa_family
def fromfd(fd, keep_fd=True):
"""Create a socket from a file descriptor
@ -92,10 +108,15 @@ def fromfd(fd, keep_fd=True):
:return: socket.socket instance
:raises OSError: for invalid socket fd
"""
family = _raw_getsockopt(fd, socket.SOL_SOCKET, SO_DOMAIN)
typ = _raw_getsockopt(fd, socket.SOL_SOCKET, SO_TYPE)
proto = _raw_getsockopt(fd, socket.SOL_SOCKET, SO_PROTOCOL)
s
family = _raw_getsockname(fd)
if hasattr(socket, 'SO_TYPE'):
typ = _raw_getsockopt(fd, socket.SOL_SOCKET, getattr(socket, 'SO_TYPE'))
else:
typ = socket.SOCK_STREAM
if hasattr(socket, 'SO_PROTOCOL'):
proto = _raw_getsockopt(fd, socket.SOL_SOCKET, getattr(socket, 'SO_PROTOCOL'))
else:
proto = 0
if keep_fd:
return socket.fromfd(fd, family, typ, proto)
else: