RAHHH

backend/lib/python3.12/site-packages/twisted/internet/test/_posixifaces.py

@@ -0,0 +1,169 @@
+# Copyright (c) Twisted Matrix Laboratories.
+# See LICENSE for details.
+
+"""
+POSIX implementation of local network interface enumeration.
+"""
+
+
+import socket
+import sys
+from ctypes import (
+    CDLL,
+    POINTER,
+    Structure,
+    c_char_p,
+    c_int,
+    c_ubyte,
+    c_uint8,
+    c_uint32,
+    c_ushort,
+    c_void_p,
+    cast,
+    pointer,
+)
+from ctypes.util import find_library
+from socket import AF_INET, AF_INET6, inet_ntop
+from typing import Any, List, Tuple
+
+from twisted.python.compat import nativeString
+
+libc = CDLL(find_library("c") or "")
+
+if sys.platform.startswith("freebsd") or sys.platform == "darwin":
+    _sockaddrCommon: List[Tuple[str, Any]] = [
+        ("sin_len", c_uint8),
+        ("sin_family", c_uint8),
+    ]
+else:
+    _sockaddrCommon: List[Tuple[str, Any]] = [
+        ("sin_family", c_ushort),
+    ]
+
+
+class in_addr(Structure):
+    _fields_ = [
+        ("in_addr", c_ubyte * 4),
+    ]
+
+
+class in6_addr(Structure):
+    _fields_ = [
+        ("in_addr", c_ubyte * 16),
+    ]
+
+
+class sockaddr(Structure):
+    _fields_ = _sockaddrCommon + [
+        ("sin_port", c_ushort),
+    ]
+
+
+class sockaddr_in(Structure):
+    _fields_ = _sockaddrCommon + [
+        ("sin_port", c_ushort),
+        ("sin_addr", in_addr),
+    ]
+
+
+class sockaddr_in6(Structure):
+    _fields_ = _sockaddrCommon + [
+        ("sin_port", c_ushort),
+        ("sin_flowinfo", c_uint32),
+        ("sin_addr", in6_addr),
+    ]
+
+
+class ifaddrs(Structure):
+    pass
+
+
+ifaddrs_p = POINTER(ifaddrs)
+ifaddrs._fields_ = [
+    ("ifa_next", ifaddrs_p),
+    ("ifa_name", c_char_p),
+    ("ifa_flags", c_uint32),
+    ("ifa_addr", POINTER(sockaddr)),
+    ("ifa_netmask", POINTER(sockaddr)),
+    ("ifa_dstaddr", POINTER(sockaddr)),
+    ("ifa_data", c_void_p),
+]
+
+getifaddrs = libc.getifaddrs
+getifaddrs.argtypes = [POINTER(ifaddrs_p)]
+getifaddrs.restype = c_int
+
+freeifaddrs = libc.freeifaddrs
+freeifaddrs.argtypes = [ifaddrs_p]
+
+
+def _maybeCleanupScopeIndex(family, packed):
+    """
+    On FreeBSD, kill the embedded interface indices in link-local scoped
+    addresses.
+
+    @param family: The address family of the packed address - one of the
+        I{socket.AF_*} constants.
+
+    @param packed: The packed representation of the address (ie, the bytes of a
+        I{in_addr} field).
+    @type packed: L{bytes}
+
+    @return: The packed address with any FreeBSD-specific extra bits cleared.
+    @rtype: L{bytes}
+
+    @see: U{https://twistedmatrix.com/trac/ticket/6843}
+    @see: U{http://www.freebsd.org/doc/en/books/developers-handbook/ipv6.html#ipv6-scope-index}
+
+    @note: Indications are that the need for this will be gone in FreeBSD >=10.
+    """
+    if sys.platform.startswith("freebsd") and packed[:2] == b"\xfe\x80":
+        return packed[:2] + b"\x00\x00" + packed[4:]
+    return packed
+
+
+def _interfaces():
+    """
+    Call C{getifaddrs(3)} and return a list of tuples of interface name, address
+    family, and human-readable address representing its results.
+    """
+    ifaddrs = ifaddrs_p()
+    if getifaddrs(pointer(ifaddrs)) < 0:
+        raise OSError()
+    results = []
+    try:
+        while ifaddrs:
+            if ifaddrs[0].ifa_addr:
+                family = ifaddrs[0].ifa_addr[0].sin_family
+                if family == AF_INET:
+                    addr = cast(ifaddrs[0].ifa_addr, POINTER(sockaddr_in))
+                elif family == AF_INET6:
+                    addr = cast(ifaddrs[0].ifa_addr, POINTER(sockaddr_in6))
+                else:
+                    addr = None
+
+                if addr:
+                    packed = bytes(addr[0].sin_addr.in_addr[:])
+                    packed = _maybeCleanupScopeIndex(family, packed)
+                    results.append(
+                        (ifaddrs[0].ifa_name, family, inet_ntop(family, packed))
+                    )
+
+            ifaddrs = ifaddrs[0].ifa_next
+    finally:
+        freeifaddrs(ifaddrs)
+    return results
+
+
+def posixGetLinkLocalIPv6Addresses():
+    """
+    Return a list of strings in colon-hex format representing all the link local
+    IPv6 addresses available on the system, as reported by I{getifaddrs(3)}.
+    """
+    retList = []
+    for interface, family, address in _interfaces():
+        interface = nativeString(interface)
+        address = nativeString(address)
+        if family == socket.AF_INET6 and address.startswith("fe80:"):
+            retList.append(f"{address}%{interface}")
+    return retList