Android系统DHCP问题 _android系统

不操千曲而后晓声，观千剑而后识器。这篇文章主要讲述Android系统DHCP问题相关的知识，希望能为你提供帮助。
本文转载自：http://blog.csdn.net/tankai19880619/article/details/42972551
一、现象
【Android系统DHCP问题】12小时压测wifi连接后，发现网络连接中断；相关log：
我们关心状态变化部分ConnectivityService: ConnectivityChange for WIFI
[plain] view plain copy

01-19-17:42; 0501-01 08:00:38.552 954 1117 D ConnectivityService: --NetworkStateTracker.EVENT_STATE_CHANGED handle--
01-19-17:42; 0501-01 08:00:38.552 954 1117 D ConnectivityService: ConnectivityChange for WIFI: CONNECTED/CONNECTED
01-19-17:42; 0501-01 08:00:38.552 954 1117 D ConnectivityService: Setting TCP values: [524288,1048576,2097152,262144,524288,1048576] which comes from [net.tcp.buffersize.wifi]
/////////////////////////////////////////////////////////////////////////////////////////////////////12hago
01-20-05:14; 2201-01 19:33:18.943 1267 1386 V shizx : @@@clienttype:@@@TCL-CN-MT55CD-F3700A-LG
01-20-05:14; 22ERROR!!! MlmeEnqueueForRecv: un-recongnized mgmt-> subtype=15
01-20-05:14; 2301-01 19:33:19.572 954 1808 E Dhinit:
01-20-05:14; 23 waitpid returned pid 1835, status = 00000009
01-20-05:14; 23cpStateMacinit: process ‘dhcpcd_wlan0‘, pid 1835 exited
01-20-05:14; 23hine: DHCP failed on wlan0: Timed out waiting for DHCP Renew to finish
01-20-05:14; 2301-01 19:33:19.574 954 1808 D DHCP : ifc_init, return = 0
01-20-05:14; 2301-01 19:33:19.574 954 1808 D DHCP : ifc_set_addr(wlan0, xx) = 0
01-20-05:14; 2301-01 19:33:19.574 954 1808 D DHCP : ifc_close
01-20-05:14; 2301-01 19:33:19.779 954 1115 D WifiHW : send cmd is DRIVER POWERMODE 0
01-20-05:14; 2301-01 19:33:19.779 954 1115 D WifiHW : send cmd is DRIVER BTCOEXMODE 2
01-20-05:14; 2301-01 19:33:19.781 954 1115 E WifiStateMachine: IP configuration failed
01-20-05:14; 2301-01 19:33:19.781 954 1115 D WifiHW : send cmd is DISCONNECT
01-20-05:14; 2301-01 19:33:19.782 1558 1558 D wpa_supplicant: wpa_driver_wext_deauthenticate
01-20-05:14; 2301-01 19:33:19.789 1558 1558 D wpa_supplicant: wpa_driver_wext_set_key: alg=0 key_idx=0 set_tx=0 seq_len=0 key_len=0
01-20-05:14; 2301-01 19:33:19.790 1558 1558 D wpa_supplicant: wpa_driver_wext_set_key: alg=0 key_idx=1 set_tx=0 seq_len=0 key_len=0
01-20-05:14; 2301-01 19:33:19.790 954 1110 D NetdConnector: RCV < - {600 Iface linkstate wlan0 up}
01-20-05:14; 2301-01 19:33:19.793 1558 1558 D wpa_supplicant: wpa_driver_wext_set_key: alg=0 key_idx=2 set_tx=0 seq_len=0 key_len=0
01-20-05:14; 2301-01 19:33:19.793 1558 1558 D wpa_supplicant: wpa_driver_wext_set_key: alg=0 key_idx=3 set_tx=0 seq_len=0 key_len=0
01-20-05:14; 2301-01 19:33:19.794 1558 1558 D wpa_supplicant: wpa_driver_wext_set_key: alg=0 key_idx=0 set_tx=0 seq_len=0 key_len=0
01-20-05:14; 2301-01 19:33:19.795 1558 1558 D wpa_supplicant: wpa_driver_wext_set_operstate: operstate 1-> 0 (DORMANT)
01-20-05:14; 2301-01 19:33:19.795 1558 1558 D wpa_supplicant: netlinkinit:
01-20-05:14; 23 waitpid returned pid 1126, status = 00000009
01-20-05:14; 23init: process ‘dhcpcd_eth0‘, pid 1126 exited
01-20-05:14; 23: Operstate: linkmode=-1, operstate=5

二、分析
关键部分：
[plain] view plain copy

DhcpStateMachine: DHCP failed on wlan0: Timed out waiting for DHCP Renew to finish
init: waitpid returned pid 1835, status = 00000009
init: process ‘dhcpcd_wlan0‘, pid 1835 exited

1.frameworks/base/core/java/android/net/DhcpStateMachine.java
[java] view plain copy

private boolean runDhcp(DhcpAction dhcpAction) {
if (dhcpAction == DhcpAction.START) {
if (DBG) Log.d(TAG, "DHCP request on " + mInterfaceName);
success = NetworkUtils.runDhcp(mInterfaceName, dhcpInfoInternal);
mDhcpInfo = dhcpInfoInternal;
} else if (dhcpAction == DhcpAction.RENEW) {
if (DBG) Log.d(TAG, "DHCP renewal on " + mInterfaceName);
success = NetworkUtils.runDhcpRenew(mInterfaceName, dhcpInfoInternal); //f分析该函数
dhcpInfoInternal.updateFromDhcpRequest(mDhcpInfo);
}
if (success) {
......
} else {
//这里就是打印：DhcpStateMachine: DHCP failed on wlan0: Timed out waiting for DHCP Renew to finish
Log.e(TAG, "DHCP failed on " + mInterfaceName + ": " +
NetworkUtils.getDhcpError());
NetworkUtils.stopDhcp(mInterfaceName);
mController.obtainMessage(CMD_POST_DHCP_ACTION, DHCP_FAILURE, 0)
.sendToTarget();
}
return success;
}

2.frameworks/base/core/java/android/net/NetworkUtils.java
[java] view plain copy

public native static boolean runDhcpRenew(String interfaceName, DhcpInfoInternal ipInfo);

3.frameworks/base/core/jni/android_net_NetUtils.cpp
[cpp] view plain copy

static jboolean android_net_utils_runDhcpRenew(JNIEnv* env, jobject clazz, jstring ifname, jobject info)
{
return android_net_utils_runDhcpCommon(env, clazz, ifname, info, true);
}
static jboolean android_net_utils_runDhcpCommon(JNIEnv* env, jobject clazz, jstring ifname,
jobject info, bool renew)
{
if (renew) {
result = ::dhcp_do_request_renew(nameStr, ipaddr, gateway, & prefixLength,
dns1, dns2, server, & lease, vendorInfo);
}
}

4.system/core/libnetutils/dhcp_utils.c
[cpp] view plain copy

int dhcp_do_request_renew(const char *interface,
char *ipaddr,
char *gateway,
uint32_t *prefixLength,
char *dns[],
char *server,
uint32_t *lease,
char *vendorInfo,
char *domain,
char *mtu)
{
if (wait_for_property(result_prop_name, NULL, 30) < 0) {
snprintf(errmsg, sizeof(errmsg), "%s", "Timed out waiting for DHCP Renew to finish"); //这是最关键的错误部分
return -1;
}
}
static int wait_for_property(const char *name, const char *desired_value, int maxwait)
{
char value[PROPERTY_VALUE_MAX] = {‘\0‘};
int maxnaps = (maxwait * 1000) / NAP_TIME;
if (maxnaps < 1) {
maxnaps = 1;
}
//add by tank
// add for MStar Android Patch Begin
maxnaps = maxnaps + 1;
usleep(50*1000);
// add for MStar Android Patch End
//end tank
while (maxnaps-- > 0) {
usleep(NAP_TIME * 1000);
if (property_get(name, value, NULL)) {
if (desired_value == NULL ||
strcmp(value, desired_value) == 0) {
return 0;
}
}
//add by [email protected]
// add for MStar Android Patch Begin
usleep(NAP_TIME * 1000);
// add for MStar Android Patch End
//end tank
}
return -1; /* failure */
}

三、解决
合入上处4中add by tank后问题解决。
其他问题，mac地址冲突导致重启后无法获取IP。
[plain] view plain copy

D/NetdConnector( 958): RCV < - {213 5c:36:b8:4d:ab:7a 0.0.0.0 0 [up broadcast multicast]}
D/NetdConnector( 958): RSP < - {213 5c:36:b8:4d:ab:7a 0.0.0.0 0 [up broadcast multicast]}
D/NetworkManagementService( 958): rsp < 213 5c:36:b8:4d:ab:7a 0.0.0.0 0 [up broadcast multicast]>
D/NetworkManagementService( 958): flags < [up broadcast multicast]>
D/NetworkManagementService( 958): Registering observer
I/EthernetStateTracker( 958): reset device eth0
D/NetUtils( 958): android_net_utils_resetConnections in env=0x7d6950 clazz=0xad200001 iface=eth0 mask=0x3
D/DHCP ( 958): ifc_init, return = 0
D/DHCP ( 958): ifc_close
D/DHCP ( 958): ifc_init, return = 0
D/DHCP ( 958): ifc_up(eth0) = 0
D/DHCP ( 958): ifc_close
D/DHCP ( 958): ifc_init, return = 0
D/DHCP ( 958): ifc_close
D/DHCP ( 958): ifc_init, return = 0
D/DHCP ( 958): ifc_close
D/dhcp ( 1124): enter dhcpcd service
D/dhcp ( 1124): enter dhcpcd service add options
D/dhcp ( 1124): enter dhcpcd service leave option
D/dhcp ( 1124): enter dhcpcd service chdir
D/dhcp ( 1124): enter dhcpcd service dump
D/dhcp ( 1124): enter dhcpcd service master
E/dhcp ( 1124): version 5.2.10 starting
D/DHCP ( 1124): ifc_init, return = 0
D/DHCP ( 1124): ifc_close
F/dhcp ( 1124): eth0: using hwaddr 5c:36:b8:4d:ab:7a
F/dhcp ( 1124): eth0: executing `/system/etc/dhcpcd/dhcpcd-run-hooks‘, reason PREINIT
I/dhcp ( 1124): host does not support a monotonic clock - timing can skew
F/dhcp ( 1124): eth0: reading lease `/data/misc/dhcp/dhcpcd-eth0.lease‘
E/dhcp ( 1124): eth0: broadcasting for a lease
F/dhcp ( 1124): eth0: sending DISCOVER (xid 0xd92bbde3), next in 3.54 seconds