如何找到本地IP地址(即192.168.x。x或10.0.x.x)在Python平台独立,只使用标准库?


当前回答

一个我不相信已经发布的版本。 我在Ubuntu 12.04上使用python 2.7进行测试。

找到这个解决方案:http://code.activestate.com/recipes/439094-get-the-ip-address-associated-with-a-network-inter/

import socket
import fcntl
import struct

def get_ip_address(ifname):
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    return socket.inet_ntoa(fcntl.ioctl(
        s.fileno(),
        0x8915,  # SIOCGIFADDR
        struct.pack('256s', ifname[:15])
    )[20:24])

结果示例:

>>> get_ip_address('eth0')
'38.113.228.130'

其他回答

import socket
socket.gethostbyname(socket.gethostname())

这并不总是有效(在/etc/hosts主机名为127.0.0.1的机器上返回127.0.0.1),gimel显示的是一个缓和的方法,使用socket.getfqdn()代替。当然,您的机器需要一个可解析的主机名。

这是UnkwnTech的答案的变体——它提供了一个get_local_addr()函数,该函数返回主机的主LAN ip地址。我发布它是因为这增加了一些东西:ipv6支持,错误处理,忽略localhost/linklocal地址,并使用TESTNET地址(rfc5737)来连接。

# imports
import errno
import socket
import logging

# localhost prefixes
_local_networks = ("127.", "0:0:0:0:0:0:0:1")

# ignore these prefixes -- localhost, unspecified, and link-local
_ignored_networks = _local_networks + ("0.", "0:0:0:0:0:0:0:0", "169.254.", "fe80:")

def detect_family(addr):
    if "." in addr:
        assert ":" not in addr
        return socket.AF_INET
    elif ":" in addr:
        return socket.AF_INET6
    else:
        raise ValueError("invalid ipv4/6 address: %r" % addr)

def expand_addr(addr):
    """convert address into canonical expanded form --
    no leading zeroes in groups, and for ipv6: lowercase hex, no collapsed groups.
    """
    family = detect_family(addr)
    addr = socket.inet_ntop(family, socket.inet_pton(family, addr))
    if "::" in addr:
        count = 8-addr.count(":")
        addr = addr.replace("::", (":0" * count) + ":")
        if addr.startswith(":"):
            addr = "0" + addr
    return addr

def _get_local_addr(family, remote):
    try:
        s = socket.socket(family, socket.SOCK_DGRAM)
        try:
            s.connect((remote, 9))
            return s.getsockname()[0]
        finally:
            s.close()
    except socket.error:
        # log.info("trapped error connecting to %r via %r", remote, family, exc_info=True)
        return None

def get_local_addr(remote=None, ipv6=True):
    """get LAN address of host

    :param remote:
        return  LAN address that host would use to access that specific remote address.
        by default, returns address it would use to access the public internet.

    :param ipv6:
        by default, attempts to find an ipv6 address first.
        if set to False, only checks ipv4.

    :returns:
        primary LAN address for host, or ``None`` if couldn't be determined.
    """
    if remote:
        family = detect_family(remote)
        local = _get_local_addr(family, remote)
        if not local:
            return None
        if family == socket.AF_INET6:
            # expand zero groups so the startswith() test works.
            local = expand_addr(local)
        if local.startswith(_local_networks):
            # border case where remote addr belongs to host
            return local
    else:
        # NOTE: the two addresses used here are TESTNET addresses,
        #       which should never exist in the real world.
        if ipv6:
            local = _get_local_addr(socket.AF_INET6, "2001:db8::1234")
            # expand zero groups so the startswith() test works.
            if local:
                local = expand_addr(local)
        else:
            local = None
        if not local:
            local = _get_local_addr(socket.AF_INET, "192.0.2.123")
            if not local:
                return None
    if local.startswith(_ignored_networks):
        return None
    return local

一台计算机可以有多个网络接口(包括您提到的本地环回127.0.0.1)。就操作系统而言,它也是一个“真实IP地址”。

如果你想跟踪所有的接口,看看下面的Python包,参见:http://alastairs-place.net/netifaces/

我认为,如果您从主机文件中删除环回条目,就可以避免gethostbyname返回127.0.0.1。(有待核实)。

我必须解决“判断一个IP地址是否是本地的”这个问题,我的第一个想法是建立一个本地IP列表,然后与之匹配。这让我想到了这个问题。然而,我后来意识到有一种更直接的方法:尝试绑定该IP,看看它是否有效。

_local_ip_cache = []
_nonlocal_ip_cache = []
def ip_islocal(ip):
    if ip in _local_ip_cache:
        return True
    if ip in _nonlocal_ip_cache:
        return False
    s = socket.socket()
    try:
        try:
            s.bind((ip, 0))
        except socket.error, e:
            if e.args[0] == errno.EADDRNOTAVAIL:
                _nonlocal_ip_cache.append(ip)
                return False
            else:
                raise
    finally:
        s.close()
    _local_ip_cache.append(ip)
    return True

我知道这并不能直接回答问题,但是这对于任何试图解决相关问题的人以及遵循相同思路的人都是有帮助的。我认为这是一个跨平台的解决方案。

对于linux env,读取/proc/net/tcp,第二个(localaddress)和第三个(remoteaddress)将以六进制格式给出ip。

提示:如果第二列是零(00000000:000),那么它是一个监听端口:)

https://github.com/romol0s/python/blob/master/general/functions/getTcpListenIpsByPort.py

https://www.kernel.org/doc/Documentation/networking/proc_net_tcp.txt