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

对于*nix系统上的IP地址列表,

import subprocess
co = subprocess.Popen(['ifconfig'], stdout = subprocess.PIPE)
ifconfig = co.stdout.read()
ip_regex = re.compile('((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-4]|2[0-5][0-9]|[01]?[0-9][0-9]?))')
[match[0] for match in ip_regex.findall(ifconfig, re.MULTILINE)]

虽然现在回答这个问题有点晚了,但我认为其他人可能会发现它有用:-)

PS:它会返回广播地址和网络掩码。

其他回答

@fatal_error解决方案应该是接受的答案!这是他的解决方案在nodejs中的实现,以备人们需要:

const dgram = require('dgram');

async function get_local_ip() {
    const s = new dgram.createSocket('udp4');
    return new Promise((resolve, reject) => {
        try {
            s.connect(1, '8.8.8.8', function () {
                const ip = s.address();
                s.close();
                resolve(ip.address)
            });
        } catch (e) {
            console.error(e);
            s.close();
            reject(e);
        }
    })
}

Socket API方法

参见https://stackoverflow.com/a/28950776/711085

缺点:

Not cross-platform. Requires more fallback code, tied to existence of particular addresses on the internet This will also not work if you're behind a NAT Probably creates a UDP connection, not independent of (usually ISP's) DNS availability (see other answers for ideas like using 8.8.8.8: Google's (coincidentally also DNS) server) Make sure you make the destination address UNREACHABLE, like a numeric IP address that is spec-guaranteed to be unused. Do NOT use some domain like fakesubdomain.google.com or somefakewebsite.com; you'll still be spamming that party (now or in the future), and spamming your own network boxes as well in the process.


反射器方法

(请注意,这并没有回答OP的本地IP地址问题,例如192.168…;它会给你你的公共IP地址,根据用例,这可能更可取。)

你可以查询一些网站,如whatismyip.com(但有一个API),例如:

from urllib.request import urlopen
import re
def getPublicIp():
    data = str(urlopen('http://checkip.dyndns.com/').read())
    # data = '<html><head><title>Current IP Check</title></head><body>Current IP Address: 65.96.168.198</body></html>\r\n'

    return re.compile(r'Address: (\d+\.\d+\.\d+\.\d+)').search(data).group(1)

或者如果使用python2:

from urllib import urlopen
import re
def getPublicIp():
    data = str(urlopen('http://checkip.dyndns.com/').read())
    # data = '<html><head><title>Current IP Check</title></head><body>Current IP Address: 65.96.168.198</body></html>\r\n'

    return re.compile(r'Address: (\d+\.\d+\.\d+\.\d+)').search(data).group(1)

优点:

这种方法的一个优点是它是跨平台的 它从丑陋的nat(例如你的家用路由器)后面工作。

缺点(和变通方法):

要求网站正常运行,格式不变(几乎肯定不会),DNS服务器正常工作。在失败的情况下,还可以通过查询其他第三方IP地址反射器来缓解这个问题。 如果您不查询多个反射器(以防止一个受损害的反射器告诉您您的地址不是某个东西),或者如果您不使用HTTPS(以防止假装是服务器的中间人攻击),则可能的攻击向量


edit: Though initially I thought these methods were really bad (unless you use many fallbacks, the code may be irrelevant many years from now), it does pose the question "what is the internet?". A computer may have many interfaces pointing to many different networks. For a more thorough description of the topic, google for gateways and routes. A computer may be able to access an internal network via an internal gateway, or access the world-wide web via a gateway on for example a router (usually the case). The local IP address that the OP asks about is only well-defined with respect to a single link layer, so you have to specify that ("is it the network card, or the ethernet cable, which we're talking about?"). There may be multiple non-unique answers to this question as posed. However the global IP address on the world-wide web is probably well-defined (in the absence of massive network fragmentation): probably the return path via the gateway which can access the TLDs.

供您参考,我可以验证该方法:

import socket
addr = socket.gethostbyname(socket.gethostname())

适用于OS X (10.6,10.5), Windows XP和管理良好的RHEL部门服务器。它不能在一个非常小的CentOS虚拟机上工作,我只是做了一些内核黑客。因此,对于该实例,您可以检查127.0.0.1地址,在这种情况下,执行以下操作:

if addr == "127.0.0.1":
     import commands
     output = commands.getoutput("/sbin/ifconfig")
     addr = parseaddress(output)

然后从输出中解析ip地址。应该注意的是,默认情况下ifconfig不在普通用户的PATH中,这就是为什么我在命令中给出完整的路径。我希望这能有所帮助。

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)。