Merge "Move attach*Filter() and addArpEntry() methods to NetworkStack" (5ce683ea) · Commits · e / os / android_packages_modules_NetworkStack

Android.bp

+22 −0

Original line number	Diff line number	Diff line
		@@ -49,6 +49,27 @@ android_library {
		manifest: "AndroidManifestBase.xml",
		}

		cc_library_shared {
		name: "libnetworkstackutilsjni",
		srcs: [
		"jni/network_stack_utils_jni.cpp"
		],

		shared_libs: [
		"liblog",
		"libcutils",
		"libnativehelper",
		],
		static_libs: [
		"libpcap",
		],
		cflags: [
		"-Wall",
		"-Werror",
		"-Wno-unused-parameter",
		],
		}

		java_defaults {
		name: "NetworkStackAppCommon",
		defaults: ["NetworkStackCommon"],
		@@ -56,6 +77,7 @@ java_defaults {
		static_libs: [
		"NetworkStackBase",
		],
		jni_libs: ["libnetworkstackutilsjni"],
		// Resources already included in NetworkStackBase
		resource_dirs: [],
		jarjar_rules: "jarjar-rules-shared.txt",

jni/network_stack_utils_jni.cpp

0 → 100644

+264 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright 2019, The Android Open Source Project
		*
		* Licensed under the Apache License, Version 2.0 (the "License");
		* you may not use this file except in compliance with the License.
		* You may obtain a copy of the License at
		*
		* http://www.apache.org/licenses/LICENSE-2.0
		*
		* Unless required by applicable law or agreed to in writing, software
		* distributed under the License is distributed on an "AS IS" BASIS,
		* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
		* See the License for the specific language governing permissions and
		* limitations under the License.
		*/

		#define LOG_TAG "NetworkStackUtils-JNI"

		#include <errno.h>
		#include <jni.h>
		#include <linux/filter.h>
		#include <linux/if_arp.h>
		#include <net/if.h>
		#include <netinet/ether.h>
		#include <netinet/icmp6.h>
		#include <netinet/ip.h>
		#include <netinet/ip6.h>
		#include <netinet/udp.h>
		#include <stdlib.h>

		#include <string>

		#include <nativehelper/JNIHelp.h>
		#include <utils/Log.h>

		namespace android {
		constexpr const char NETWORKSTACKUTILS_PKG_NAME[] = "android/net/util/NetworkStackUtils";

		static const uint32_t kEtherTypeOffset = offsetof(ether_header, ether_type);
		static const uint32_t kEtherHeaderLen = sizeof(ether_header);
		static const uint32_t kIPv4Protocol = kEtherHeaderLen + offsetof(iphdr, protocol);
		static const uint32_t kIPv4FlagsOffset = kEtherHeaderLen + offsetof(iphdr, frag_off);
		static const uint32_t kIPv6NextHeader = kEtherHeaderLen + offsetof(ip6_hdr, ip6_nxt);
		static const uint32_t kIPv6PayloadStart = kEtherHeaderLen + sizeof(ip6_hdr);
		static const uint32_t kICMPv6TypeOffset = kIPv6PayloadStart + offsetof(icmp6_hdr, icmp6_type);
		static const uint32_t kUDPSrcPortIndirectOffset = kEtherHeaderLen + offsetof(udphdr, source);
		static const uint32_t kUDPDstPortIndirectOffset = kEtherHeaderLen + offsetof(udphdr, dest);
		static const uint16_t kDhcpClientPort = 68;

		static bool checkLenAndCopy(JNIEnv* env, const jbyteArray& addr, int len, void* dst) {
		if (env->GetArrayLength(addr) != len) {
		return false;
		}
		env->GetByteArrayRegion(addr, 0, len, reinterpret_cast<jbyte*>(dst));
		return true;
		}

		static void network_stack_utils_addArpEntry(JNIEnv *env, jobject thiz, jbyteArray ethAddr,
		jbyteArray ipv4Addr, jstring ifname, jobject javaFd) {
		arpreq req = {};
		sockaddr_in& netAddrStruct = reinterpret_cast<sockaddr_in>(&req.arp_pa);
		sockaddr& ethAddrStruct = req.arp_ha;

		ethAddrStruct.sa_family = ARPHRD_ETHER;
		if (!checkLenAndCopy(env, ethAddr, ETH_ALEN, ethAddrStruct.sa_data)) {
		jniThrowException(env, "java/io/IOException", "Invalid ethAddr length");
		return;
		}

		netAddrStruct.sin_family = AF_INET;
		if (!checkLenAndCopy(env, ipv4Addr, sizeof(in_addr), &netAddrStruct.sin_addr)) {
		jniThrowException(env, "java/io/IOException", "Invalid ipv4Addr length");
		return;
		}

		int ifLen = env->GetStringLength(ifname);
		// IFNAMSIZ includes the terminating NULL character
		if (ifLen >= IFNAMSIZ) {
		jniThrowException(env, "java/io/IOException", "ifname too long");
		return;
		}
		env->GetStringUTFRegion(ifname, 0, ifLen, req.arp_dev);

		req.arp_flags = ATF_COM; // Completed entry (ha valid)
		int fd = jniGetFDFromFileDescriptor(env, javaFd);
		if (fd < 0) {
		jniThrowExceptionFmt(env, "java/io/IOException", "Invalid file descriptor");
		return;
		}
		// See also: man 7 arp
		if (ioctl(fd, SIOCSARP, &req)) {
		jniThrowExceptionFmt(env, "java/io/IOException", "ioctl error: %s", strerror(errno));
		return;
		}
		}

		static void network_stack_utils_attachDhcpFilter(JNIEnv *env, jobject clazz, jobject javaFd) {
		static sock_filter filter_code[] = {
		// Check the protocol is UDP.
		BPF_STMT(BPF_LD \| BPF_B \| BPF_ABS, kIPv4Protocol),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, IPPROTO_UDP, 0, 6),

		// Check this is not a fragment.
		BPF_STMT(BPF_LD \| BPF_H \| BPF_ABS, kIPv4FlagsOffset),
		BPF_JUMP(BPF_JMP \| BPF_JSET \| BPF_K, IP_OFFMASK, 4, 0),

		// Get the IP header length.
		BPF_STMT(BPF_LDX \| BPF_B \| BPF_MSH, kEtherHeaderLen),

		// Check the destination port.
		BPF_STMT(BPF_LD \| BPF_H \| BPF_IND, kUDPDstPortIndirectOffset),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, kDhcpClientPort, 0, 1),

		// Accept or reject.
		BPF_STMT(BPF_RET \| BPF_K, 0xffff),
		BPF_STMT(BPF_RET \| BPF_K, 0)
		};
		static const sock_fprog filter = {
		sizeof(filter_code) / sizeof(filter_code[0]),
		filter_code,
		};

		int fd = jniGetFDFromFileDescriptor(env, javaFd);
		if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)) != 0) {
		jniThrowExceptionFmt(env, "java/net/SocketException",
		"setsockopt(SO_ATTACH_FILTER): %s", strerror(errno));
		}
		}

		static void network_stack_utils_attachRaFilter(JNIEnv *env, jobject clazz, jobject javaFd,
		jint hardwareAddressType) {
		if (hardwareAddressType != ARPHRD_ETHER) {
		jniThrowExceptionFmt(env, "java/net/SocketException",
		"attachRaFilter only supports ARPHRD_ETHER");
		return;
		}

		static sock_filter filter_code[] = {
		// Check IPv6 Next Header is ICMPv6.
		BPF_STMT(BPF_LD \| BPF_B \| BPF_ABS, kIPv6NextHeader),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, IPPROTO_ICMPV6, 0, 3),

		// Check ICMPv6 type is Router Advertisement.
		BPF_STMT(BPF_LD \| BPF_B \| BPF_ABS, kICMPv6TypeOffset),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, ND_ROUTER_ADVERT, 0, 1),

		// Accept or reject.
		BPF_STMT(BPF_RET \| BPF_K, 0xffff),
		BPF_STMT(BPF_RET \| BPF_K, 0)
		};
		static const sock_fprog filter = {
		sizeof(filter_code) / sizeof(filter_code[0]),
		filter_code,
		};

		int fd = jniGetFDFromFileDescriptor(env, javaFd);
		if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)) != 0) {
		jniThrowExceptionFmt(env, "java/net/SocketException",
		"setsockopt(SO_ATTACH_FILTER): %s", strerror(errno));
		}
		}

		// TODO: Move all this filter code into libnetutils.
		static void network_stack_utils_attachControlPacketFilter(
		JNIEnv *env, jobject clazz, jobject javaFd, jint hardwareAddressType) {
		if (hardwareAddressType != ARPHRD_ETHER) {
		jniThrowExceptionFmt(env, "java/net/SocketException",
		"attachControlPacketFilter only supports ARPHRD_ETHER");
		return;
		}

		// Capture all:
		// - ARPs
		// - DHCPv4 packets
		// - Router Advertisements & Solicitations
		// - Neighbor Advertisements & Solicitations
		//
		// tcpdump:
		// arp or
		// '(ip and udp port 68)' or
		// '(icmp6 and ip6[40] >= 133 and ip6[40] <= 136)'
		static sock_filter filter_code[] = {
		// Load the link layer next payload field.
		BPF_STMT(BPF_LD \| BPF_H \| BPF_ABS, kEtherTypeOffset),

		// Accept all ARP.
		// TODO: Figure out how to better filter ARPs on noisy networks.
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, ETHERTYPE_ARP, 16, 0),

		// If IPv4:
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, ETHERTYPE_IP, 0, 9),

		// Check the protocol is UDP.
		BPF_STMT(BPF_LD \| BPF_B \| BPF_ABS, kIPv4Protocol),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, IPPROTO_UDP, 0, 14),

		// Check this is not a fragment.
		BPF_STMT(BPF_LD \| BPF_H \| BPF_ABS, kIPv4FlagsOffset),
		BPF_JUMP(BPF_JMP \| BPF_JSET \| BPF_K, IP_OFFMASK, 12, 0),

		// Get the IP header length.
		BPF_STMT(BPF_LDX \| BPF_B \| BPF_MSH, kEtherHeaderLen),

		// Check the source port.
		BPF_STMT(BPF_LD \| BPF_H \| BPF_IND, kUDPSrcPortIndirectOffset),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, kDhcpClientPort, 8, 0),

		// Check the destination port.
		BPF_STMT(BPF_LD \| BPF_H \| BPF_IND, kUDPDstPortIndirectOffset),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, kDhcpClientPort, 6, 7),

		// IPv6 ...
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, ETHERTYPE_IPV6, 0, 6),
		// ... check IPv6 Next Header is ICMPv6 (ignore fragments), ...
		BPF_STMT(BPF_LD \| BPF_B \| BPF_ABS, kIPv6NextHeader),
		BPF_JUMP(BPF_JMP \| BPF_JEQ \| BPF_K, IPPROTO_ICMPV6, 0, 4),
		// ... and check the ICMPv6 type is one of RS/RA/NS/NA.
		BPF_STMT(BPF_LD \| BPF_B \| BPF_ABS, kICMPv6TypeOffset),
		BPF_JUMP(BPF_JMP \| BPF_JGE \| BPF_K, ND_ROUTER_SOLICIT, 0, 2),
		BPF_JUMP(BPF_JMP \| BPF_JGT \| BPF_K, ND_NEIGHBOR_ADVERT, 1, 0),

		// Accept or reject.
		BPF_STMT(BPF_RET \| BPF_K, 0xffff),
		BPF_STMT(BPF_RET \| BPF_K, 0)
		};
		static const sock_fprog filter = {
		sizeof(filter_code) / sizeof(filter_code[0]),
		filter_code,
		};

		int fd = jniGetFDFromFileDescriptor(env, javaFd);
		if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &filter, sizeof(filter)) != 0) {
		jniThrowExceptionFmt(env, "java/net/SocketException",
		"setsockopt(SO_ATTACH_FILTER): %s", strerror(errno));
		}
		}

		/*
		* JNI registration.
		*/
		static const JNINativeMethod gNetworkStackUtilsMethods[] = {
		/* name, signature, funcPtr */
		{ "addArpEntry", "([B[BLjava/lang/String;Ljava/io/FileDescriptor;)V", (void*) network_stack_utils_addArpEntry },
		{ "attachDhcpFilter", "(Ljava/io/FileDescriptor;)V", (void*) network_stack_utils_attachDhcpFilter },
		{ "attachRaFilter", "(Ljava/io/FileDescriptor;I)V", (void*) network_stack_utils_attachRaFilter },
		{ "attachControlPacketFilter", "(Ljava/io/FileDescriptor;I)V", (void*) network_stack_utils_attachControlPacketFilter },
		};

		extern "C" jint JNI_OnLoad(JavaVM* vm, void*) {
		JNIEnv *env;
		if (vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6) != JNI_OK) {
		ALOGE("ERROR: GetEnv failed");
		return JNI_ERR;
		}

		if (jniRegisterNativeMethods(env, NETWORKSTACKUTILS_PKG_NAME,
		gNetworkStackUtilsMethods, NELEM(gNetworkStackUtilsMethods)) < 0) {
		return JNI_ERR;
		}

		return JNI_VERSION_1_6;

		}
		}; // namespace android
		No newline at end of file

src/android/net/apf/ApfFilter.java

+1 −2

Original line number	Diff line number	Diff line
		@@ -49,7 +49,6 @@ import android.net.metrics.IpConnectivityLog;
		import android.net.metrics.RaEvent;
		import android.net.util.InterfaceParams;
		import android.net.util.NetworkStackUtils;
		import android.net.util.SocketUtils;
		import android.os.PowerManager;
		import android.os.SystemClock;
		import android.system.ErrnoException;
		@@ -478,7 +477,7 @@ public class ApfFilter {
		SocketAddress addr = makePacketSocketAddress(
		(short) ETH_P_IPV6, mInterfaceParams.index);
		Os.bind(socket, addr);
		SocketUtils.attachRaFilter(socket, mApfCapabilities.apfPacketFormat);
		NetworkStackUtils.attachRaFilter(socket, mApfCapabilities.apfPacketFormat);
		} catch(SocketException\|ErrnoException e) {
		Log.e(TAG, "Error starting filter", e);
		return;

src/android/net/dhcp/DhcpClient.java

+2 −1

Original line number	Diff line number	Diff line
		@@ -51,6 +51,7 @@ import android.net.metrics.DhcpClientEvent;
		import android.net.metrics.DhcpErrorEvent;
		import android.net.metrics.IpConnectivityLog;
		import android.net.util.InterfaceParams;
		import android.net.util.NetworkStackUtils;
		import android.net.util.SocketUtils;
		import android.os.Message;
		import android.os.SystemClock;
		@@ -319,7 +320,7 @@ public class DhcpClient extends StateMachine {
		mPacketSock = Os.socket(AF_PACKET, SOCK_RAW, ETH_P_IP);
		SocketAddress addr = makePacketSocketAddress((short) ETH_P_IP, mIface.index);
		Os.bind(mPacketSock, addr);
		SocketUtils.attachDhcpFilter(mPacketSock);
		NetworkStackUtils.attachDhcpFilter(mPacketSock);
		} catch(SocketException\|ErrnoException e) {
		Log.e(TAG, "Error creating packet socket", e);
		return false;

src/android/net/dhcp/DhcpServer.java

+2 −1

Original line number	Diff line number	Diff line
		@@ -45,6 +45,7 @@ import android.annotation.Nullable;
		import android.net.INetworkStackStatusCallback;
		import android.net.MacAddress;
		import android.net.TrafficStats;
		import android.net.util.NetworkStackUtils;
		import android.net.util.SharedLog;
		import android.net.util.SocketUtils;
		import android.os.Handler;
		@@ -207,7 +208,7 @@ public class DhcpServer extends IDhcpServer.Stub {
		@Override
		public void addArpEntry(@NonNull Inet4Address ipv4Addr, @NonNull MacAddress ethAddr,
		@NonNull String ifname, @NonNull FileDescriptor fd) throws IOException {
		SocketUtils.addArpEntry(ipv4Addr, ethAddr, ifname, fd);
		NetworkStackUtils.addArpEntry(ipv4Addr, ethAddr, ifname, fd);
		}

		@Override