Problem Description
Use the Android device to open the settings, select WIFI and enter the correct password to connect, it will display connected, no network, and then the network connection is limited, and you can actually use this WIFI to surf the Internet.
problem analysis
Abnormal Log
D NetworkMonitor/100: PROBE_DNS www.google.com 107ms OK 104.244.46.85
D NetworkMonitor/100: PROBE_DNS connectivitycheck.gstatic.com 118ms OK 203.208.50.66
D NetworkMonitor/100: PROBE_HTTP http://connectivitycheck.gstatic.com/generate_204 time=35ms ret=302 request={Connection=[close], User-Agent=[Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/60.0.3112.32 Safari/537.36]} headers={null=[HTTP/1.0 302 Moved Temporarily], Allow=[GET,POST,HEAD], Location=[http://10.10.1.2:8080/cn/index.html], MIME-Version=[1.0], Pragma=[No-Cache], Server=[AP Server 1.0], X-Android-Received-Millis=[1615220820212], X-Android-Response-Source=[NETWORK 302], X-Android-Selected-Protocol=[http/1.0], X-Android-Sent-Millis=[1615220820196]}
D NetworkMonitor/100: PROBE_HTTPS https://www.google.com/generate_204 Probe failed with exception javax.net.ssl.SSLHandshakeException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found.
D NetworkMonitor/100: isCaptivePortal: isSuccessful()=false isPortal()=true RedirectUrl=http://10.10.1.2:8080/cn/index.html isPartialConnectivity()=false Time=172ms
It can be seen from the log that connecting to WIFI will perform network verification to determine whether it is available. HTTP verification is successful, but HTTPS verification fails, so it will show that the network connection is limited, and there will be a short connection during the connection process. , no network is normal. The URL https://www.google.com/generate_204 for HTTPS verification, because it cannot be accessed in China, will fail the verification, and the method that can be adopted is to replace this URL.
packages/modules/NetworkStack/src/com/android/server/connectivity/NetworkMonitor.java
#校验源码部分
private CaptivePortalProbeResult sendDnsAndHttpProbes(ProxyInfo proxy, URL url, int probeType) {
// Pre-resolve the captive portal server host so we can log it.
// Only do this if HttpURLConnection is about to, to avoid any potentially
// unnecessary resolution.
final String host = (proxy != null) ? proxy.getHost() : url.getHost();
// This method cannot safely report probe results because it might not be running on the
// state machine thread. Reporting results here would cause races and potentially send
// information to callers that does not make sense because the state machine has already
// changed state.
sendDnsProbe(host);
return sendHttpProbe(url, probeType, null);
}
# HTTPS网址相关源码
private final URL mCaptivePortalHttpsUrl;
mCaptivePortalHttpsUrl = makeURL(getCaptivePortalServerHttpsUrl());
public String getCaptivePortalServerHttpUrl() {
return getSettingFromResource(mContext, R.string.config_captive_portal_http_url,
R.string.default_captive_portal_http_url, CAPTIVE_PORTAL_HTTP_URL);
}
solution
packages/modules/NetworkStack/res/values/config.xml
<!-- HTTP URL for network validation, to use for detecting captive portals. -->
<string name="default_captive_portal_http_url" translatable="false">http://connectivitycheck.gstatic.com/generate_204</string>
<!-- HTTPS URL for network validation, to use for confirming internet connectivity. -->
- <string name="default_captive_portal_https_url" translatable="false">https://www.google.com/generate_204</string>
+ <string name="default_captive_portal_https_url" translatable="false">https://developers.google.cn/generate_204</string>
There is another solution on the Internet as follows, which is to turn off the verification. This solution can realize the problem of not showing that the network connection is limited, but when connecting to the WIFI that needs to be logged in, it cannot be connected.
frameworks/base/packages/SettingsProvider/src/com/android/providers/settings/DatabaseHelper.java
loadSetting(stmt, Settings.Global.LID_BEHAVIOR, defaultLidBehavior);
loadStringSetting(stmt, Settings.Global.NTP_SERVER_2,
R.string.def_ntp_server_2);
+ loadSetting(stmt, Global.CAPTIVE_PORTAL_MODE, Global.CAPTIVE_PORTAL_MODE_IGNORE);
Regarding the value of captive_portal_mode
0: Disable detection completely
1: When it is detected that a login is required, a pop-up window will remind (default value)
2: When it is detected that a login is required, the hotspot will be automatically disconnected and no longer automatically connected