| /* |
| * Copyright (C) 2008 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. |
| */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <netdb.h> |
| #include <string.h> |
| |
| #include <sys/socket.h> |
| #include <sys/stat.h> |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| |
| #include <netinet/in.h> |
| #include <arpa/inet.h> |
| |
| #include <array> |
| #include <cstdlib> |
| #include <string> |
| #include <vector> |
| |
| #define LOG_TAG "TetherController" |
| #include <android-base/strings.h> |
| #include <android-base/stringprintf.h> |
| #include <cutils/log.h> |
| #include <cutils/properties.h> |
| #include <netdutils/StatusOr.h> |
| |
| #include "Fwmark.h" |
| #include "NetdConstants.h" |
| #include "Permission.h" |
| #include "InterfaceController.h" |
| #include "NetworkController.h" |
| #include "ResponseCode.h" |
| #include "TetherController.h" |
| |
| using android::base::Join; |
| using android::base::StringPrintf; |
| using android::base::StringAppendF; |
| using android::netdutils::StatusOr; |
| using android::netdutils::statusFromErrno; |
| |
| namespace { |
| |
| const char BP_TOOLS_MODE[] = "bp-tools"; |
| const char IPV4_FORWARDING_PROC_FILE[] = "/proc/sys/net/ipv4/ip_forward"; |
| const char IPV6_FORWARDING_PROC_FILE[] = "/proc/sys/net/ipv6/conf/all/forwarding"; |
| const char SEPARATOR[] = "|"; |
| constexpr const char kTcpBeLiberal[] = "/proc/sys/net/netfilter/nf_conntrack_tcp_be_liberal"; |
| |
| // Chosen to match AID_DNS_TETHER, as made "friendly" by fs_config_generator.py. |
| constexpr const char kDnsmasqUsername[] = "dns_tether"; |
| |
| bool writeToFile(const char* filename, const char* value) { |
| int fd = open(filename, O_WRONLY | O_CLOEXEC); |
| if (fd < 0) { |
| ALOGE("Failed to open %s: %s", filename, strerror(errno)); |
| return false; |
| } |
| |
| const ssize_t len = strlen(value); |
| if (write(fd, value, len) != len) { |
| ALOGE("Failed to write %s to %s: %s", value, filename, strerror(errno)); |
| close(fd); |
| return false; |
| } |
| close(fd); |
| return true; |
| } |
| |
| // TODO: Consider altering TCP and UDP timeouts as well. |
| void configureForTethering(bool enabled) { |
| writeToFile(kTcpBeLiberal, enabled ? "1" : "0"); |
| } |
| |
| bool configureForIPv6Router(const char *interface) { |
| return (InterfaceController::setEnableIPv6(interface, 0) == 0) |
| && (InterfaceController::setAcceptIPv6Ra(interface, 0) == 0) |
| && (InterfaceController::setAcceptIPv6Dad(interface, 0) == 0) |
| && (InterfaceController::setIPv6DadTransmits(interface, "0") == 0) |
| && (InterfaceController::setEnableIPv6(interface, 1) == 0); |
| } |
| |
| void configureForIPv6Client(const char *interface) { |
| InterfaceController::setAcceptIPv6Ra(interface, 1); |
| InterfaceController::setAcceptIPv6Dad(interface, 1); |
| InterfaceController::setIPv6DadTransmits(interface, "1"); |
| InterfaceController::setEnableIPv6(interface, 0); |
| } |
| |
| bool inBpToolsMode() { |
| // In BP tools mode, do not disable IP forwarding |
| char bootmode[PROPERTY_VALUE_MAX] = {0}; |
| property_get("ro.bootmode", bootmode, "unknown"); |
| return !strcmp(BP_TOOLS_MODE, bootmode); |
| } |
| |
| } // namespace |
| |
| namespace android { |
| namespace net { |
| |
| auto TetherController::iptablesRestoreFunction = execIptablesRestoreWithOutput; |
| |
| const int MAX_IPT_OUTPUT_LINE_LEN = 256; |
| |
| const std::string GET_TETHER_STATS_COMMAND = StringPrintf( |
| "*filter\n" |
| "-nvx -L %s\n" |
| "COMMIT\n", android::net::TetherController::LOCAL_TETHER_COUNTERS_CHAIN); |
| |
| TetherController::TetherController() { |
| mDnsNetId = 0; |
| mDaemonFd = -1; |
| mDaemonPid = 0; |
| if (inBpToolsMode()) { |
| enableForwarding(BP_TOOLS_MODE); |
| } else { |
| setIpFwdEnabled(); |
| } |
| } |
| |
| TetherController::~TetherController() { |
| mInterfaces.clear(); |
| mDnsForwarders.clear(); |
| mForwardingRequests.clear(); |
| mFwdIfaces.clear(); |
| } |
| |
| bool TetherController::setIpFwdEnabled() { |
| bool success = true; |
| const char* value = mForwardingRequests.empty() ? "0" : "1"; |
| ALOGD("Setting IP forward enable = %s", value); |
| success &= writeToFile(IPV4_FORWARDING_PROC_FILE, value); |
| success &= writeToFile(IPV6_FORWARDING_PROC_FILE, value); |
| return success; |
| } |
| |
| bool TetherController::enableForwarding(const char* requester) { |
| // Don't return an error if this requester already requested forwarding. Only return errors for |
| // things that the caller caller needs to care about, such as "couldn't write to the file to |
| // enable forwarding". |
| mForwardingRequests.insert(requester); |
| return setIpFwdEnabled(); |
| } |
| |
| bool TetherController::disableForwarding(const char* requester) { |
| mForwardingRequests.erase(requester); |
| return setIpFwdEnabled(); |
| } |
| |
| size_t TetherController::forwardingRequestCount() { |
| return mForwardingRequests.size(); |
| } |
| |
| int TetherController::startTethering(int num_addrs, char **dhcp_ranges) { |
| if (mDaemonPid != 0) { |
| ALOGE("Tethering already started"); |
| errno = EBUSY; |
| return -1; |
| } |
| |
| ALOGD("Starting tethering services"); |
| |
| pid_t pid; |
| int pipefd[2]; |
| |
| if (pipe(pipefd) < 0) { |
| ALOGE("pipe failed (%s)", strerror(errno)); |
| return -1; |
| } |
| |
| /* |
| * TODO: Create a monitoring thread to handle and restart |
| * the daemon if it exits prematurely |
| */ |
| if ((pid = fork()) < 0) { |
| ALOGE("fork failed (%s)", strerror(errno)); |
| close(pipefd[0]); |
| close(pipefd[1]); |
| return -1; |
| } |
| |
| if (!pid) { |
| close(pipefd[1]); |
| if (pipefd[0] != STDIN_FILENO) { |
| if (dup2(pipefd[0], STDIN_FILENO) != STDIN_FILENO) { |
| ALOGE("dup2 failed (%s)", strerror(errno)); |
| return -1; |
| } |
| close(pipefd[0]); |
| } |
| |
| Fwmark fwmark; |
| fwmark.netId = NetworkController::LOCAL_NET_ID; |
| fwmark.explicitlySelected = true; |
| fwmark.protectedFromVpn = true; |
| fwmark.permission = PERMISSION_SYSTEM; |
| char markStr[UINT32_HEX_STRLEN]; |
| snprintf(markStr, sizeof(markStr), "0x%x", fwmark.intValue); |
| |
| std::vector<const std::string> argVector = { |
| "/system/bin/dnsmasq", |
| "--keep-in-foreground", |
| "--no-resolv", |
| "--no-poll", |
| "--dhcp-authoritative", |
| // TODO: pipe through metered status from ConnService |
| "--dhcp-option-force=43,ANDROID_METERED", |
| "--pid-file", |
| "--listen-mark", markStr, |
| "--user", kDnsmasqUsername, |
| }; |
| |
| for (int addrIndex = 0; addrIndex < num_addrs; addrIndex += 2) { |
| argVector.push_back( |
| StringPrintf("--dhcp-range=%s,%s,1h", |
| dhcp_ranges[addrIndex], dhcp_ranges[addrIndex+1])); |
| } |
| |
| auto args = (char**)std::calloc(argVector.size() + 1, sizeof(char*)); |
| for (unsigned i = 0; i < argVector.size(); i++) { |
| args[i] = (char*)argVector[i].c_str(); |
| } |
| |
| if (execv(args[0], args)) { |
| ALOGE("execv failed (%s)", strerror(errno)); |
| } |
| ALOGE("Should never get here!"); |
| _exit(-1); |
| } else { |
| close(pipefd[0]); |
| mDaemonPid = pid; |
| mDaemonFd = pipefd[1]; |
| configureForTethering(true); |
| applyDnsInterfaces(); |
| ALOGD("Tethering services running"); |
| } |
| |
| return 0; |
| } |
| |
| int TetherController::stopTethering() { |
| configureForTethering(false); |
| |
| if (mDaemonPid == 0) { |
| ALOGE("Tethering already stopped"); |
| return 0; |
| } |
| |
| ALOGD("Stopping tethering services"); |
| |
| kill(mDaemonPid, SIGTERM); |
| waitpid(mDaemonPid, NULL, 0); |
| mDaemonPid = 0; |
| close(mDaemonFd); |
| mDaemonFd = -1; |
| ALOGD("Tethering services stopped"); |
| return 0; |
| } |
| |
| bool TetherController::isTetheringStarted() { |
| return (mDaemonPid == 0 ? false : true); |
| } |
| |
| #define MAX_CMD_SIZE 1024 |
| |
| int TetherController::setDnsForwarders(unsigned netId, char **servers, int numServers) { |
| int i; |
| char daemonCmd[MAX_CMD_SIZE]; |
| |
| Fwmark fwmark; |
| fwmark.netId = netId; |
| fwmark.explicitlySelected = true; |
| fwmark.protectedFromVpn = true; |
| fwmark.permission = PERMISSION_SYSTEM; |
| |
| snprintf(daemonCmd, sizeof(daemonCmd), "update_dns%s0x%x", SEPARATOR, fwmark.intValue); |
| int cmdLen = strlen(daemonCmd); |
| |
| mDnsForwarders.clear(); |
| for (i = 0; i < numServers; i++) { |
| ALOGD("setDnsForwarders(0x%x %d = '%s')", fwmark.intValue, i, servers[i]); |
| |
| addrinfo *res, hints = { .ai_flags = AI_NUMERICHOST }; |
| int ret = getaddrinfo(servers[i], NULL, &hints, &res); |
| freeaddrinfo(res); |
| if (ret) { |
| ALOGE("Failed to parse DNS server '%s'", servers[i]); |
| mDnsForwarders.clear(); |
| errno = EINVAL; |
| return -1; |
| } |
| |
| cmdLen += (strlen(servers[i]) + 1); |
| if (cmdLen + 1 >= MAX_CMD_SIZE) { |
| ALOGD("Too many DNS servers listed"); |
| break; |
| } |
| |
| strcat(daemonCmd, SEPARATOR); |
| strcat(daemonCmd, servers[i]); |
| mDnsForwarders.push_back(servers[i]); |
| } |
| |
| mDnsNetId = netId; |
| if (mDaemonFd != -1) { |
| ALOGD("Sending update msg to dnsmasq [%s]", daemonCmd); |
| if (write(mDaemonFd, daemonCmd, strlen(daemonCmd) +1) < 0) { |
| ALOGE("Failed to send update command to dnsmasq (%s)", strerror(errno)); |
| mDnsForwarders.clear(); |
| errno = EREMOTEIO; |
| return -1; |
| } |
| } |
| return 0; |
| } |
| |
| unsigned TetherController::getDnsNetId() { |
| return mDnsNetId; |
| } |
| |
| const std::list<std::string> &TetherController::getDnsForwarders() const { |
| return mDnsForwarders; |
| } |
| |
| bool TetherController::applyDnsInterfaces() { |
| char daemonCmd[MAX_CMD_SIZE]; |
| |
| strcpy(daemonCmd, "update_ifaces"); |
| int cmdLen = strlen(daemonCmd); |
| bool haveInterfaces = false; |
| |
| for (const auto &ifname : mInterfaces) { |
| cmdLen += (ifname.size() + 1); |
| if (cmdLen + 1 >= MAX_CMD_SIZE) { |
| ALOGD("Too many DNS ifaces listed"); |
| break; |
| } |
| |
| strcat(daemonCmd, SEPARATOR); |
| strcat(daemonCmd, ifname.c_str()); |
| haveInterfaces = true; |
| } |
| |
| if ((mDaemonFd != -1) && haveInterfaces) { |
| ALOGD("Sending update msg to dnsmasq [%s]", daemonCmd); |
| if (write(mDaemonFd, daemonCmd, strlen(daemonCmd) +1) < 0) { |
| ALOGE("Failed to send update command to dnsmasq (%s)", strerror(errno)); |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| int TetherController::tetherInterface(const char *interface) { |
| ALOGD("tetherInterface(%s)", interface); |
| if (!isIfaceName(interface)) { |
| errno = ENOENT; |
| return -1; |
| } |
| |
| if (!configureForIPv6Router(interface)) { |
| configureForIPv6Client(interface); |
| return -1; |
| } |
| mInterfaces.push_back(interface); |
| |
| if (!applyDnsInterfaces()) { |
| mInterfaces.pop_back(); |
| configureForIPv6Client(interface); |
| return -1; |
| } else { |
| return 0; |
| } |
| } |
| |
| int TetherController::untetherInterface(const char *interface) { |
| ALOGD("untetherInterface(%s)", interface); |
| |
| for (auto it = mInterfaces.cbegin(); it != mInterfaces.cend(); ++it) { |
| if (!strcmp(interface, it->c_str())) { |
| mInterfaces.erase(it); |
| |
| configureForIPv6Client(interface); |
| return applyDnsInterfaces() ? 0 : -1; |
| } |
| } |
| errno = ENOENT; |
| return -1; |
| } |
| |
| const std::list<std::string> &TetherController::getTetheredInterfaceList() const { |
| return mInterfaces; |
| } |
| |
| int TetherController::setupIptablesHooks() { |
| int res; |
| res = setDefaults(); |
| if (res < 0) { |
| return res; |
| } |
| |
| // Used to limit downstream mss to the upstream pmtu so we don't end up fragmenting every large |
| // packet tethered devices send. This is IPv4-only, because in IPv6 we send the MTU in the RA. |
| // This is no longer optional and tethering will fail to start if it fails. |
| std::string mssRewriteCommand = StringPrintf( |
| "*mangle\n" |
| "-A %s -p tcp --tcp-flags SYN SYN -j TCPMSS --clamp-mss-to-pmtu\n" |
| "COMMIT\n", LOCAL_MANGLE_FORWARD); |
| |
| // This is for tethering counters. This chain is reached via --goto, and then RETURNS. |
| std::string defaultCommands = StringPrintf( |
| "*filter\n" |
| ":%s -\n" |
| "COMMIT\n", LOCAL_TETHER_COUNTERS_CHAIN); |
| |
| res = iptablesRestoreFunction(V4, mssRewriteCommand, nullptr); |
| if (res < 0) { |
| return res; |
| } |
| |
| res = iptablesRestoreFunction(V4V6, defaultCommands, nullptr); |
| if (res < 0) { |
| return res; |
| } |
| |
| mFwdIfaces.clear(); |
| |
| return 0; |
| } |
| |
| int TetherController::setDefaults() { |
| std::string v4Cmd = StringPrintf( |
| "*filter\n" |
| ":%s -\n" |
| "-A %s -j DROP\n" |
| "COMMIT\n" |
| "*nat\n" |
| ":%s -\n" |
| "COMMIT\n", LOCAL_FORWARD, LOCAL_FORWARD, LOCAL_NAT_POSTROUTING); |
| |
| std::string v6Cmd = StringPrintf( |
| "*filter\n" |
| ":%s -\n" |
| "COMMIT\n" |
| "*raw\n" |
| ":%s -\n" |
| "COMMIT\n", LOCAL_FORWARD, LOCAL_RAW_PREROUTING); |
| |
| int res = iptablesRestoreFunction(V4, v4Cmd, nullptr); |
| if (res < 0) { |
| return res; |
| } |
| |
| res = iptablesRestoreFunction(V6, v6Cmd, nullptr); |
| if (res < 0) { |
| return res; |
| } |
| |
| return 0; |
| } |
| |
| int TetherController::enableNat(const char* intIface, const char* extIface) { |
| ALOGV("enableNat(intIface=<%s>, extIface=<%s>)",intIface, extIface); |
| |
| if (!isIfaceName(intIface) || !isIfaceName(extIface)) { |
| errno = ENODEV; |
| return -1; |
| } |
| |
| /* Bug: b/9565268. "enableNat wlan0 wlan0". For now we fail until java-land is fixed */ |
| if (!strcmp(intIface, extIface)) { |
| ALOGE("Duplicate interface specified: %s %s", intIface, extIface); |
| errno = EINVAL; |
| return -1; |
| } |
| |
| if (isForwardingPairEnabled(intIface, extIface)) { |
| return 0; |
| } |
| |
| // add this if we are the first enabled nat for this upstream |
| if (!isAnyForwardingEnabledOnUpstream(extIface)) { |
| std::vector<std::string> v4Cmds = { |
| "*nat", |
| StringPrintf("-A %s -o %s -j MASQUERADE", LOCAL_NAT_POSTROUTING, extIface), |
| "COMMIT\n" |
| }; |
| |
| if (iptablesRestoreFunction(V4, Join(v4Cmds, '\n'), nullptr) || |
| setupIPv6CountersChain()) { |
| ALOGE("Error setting postroute rule: iface=%s", extIface); |
| if (!isAnyForwardingPairEnabled()) { |
| // unwind what's been done, but don't care about success - what more could we do? |
| setDefaults(); |
| } |
| return -1; |
| } |
| } |
| |
| if (setForwardRules(true, intIface, extIface) != 0) { |
| ALOGE("Error setting forward rules"); |
| if (!isAnyForwardingPairEnabled()) { |
| setDefaults(); |
| } |
| errno = ENODEV; |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| int TetherController::setupIPv6CountersChain() { |
| // Only add this if we are the first enabled nat |
| if (isAnyForwardingPairEnabled()) { |
| return 0; |
| } |
| |
| /* |
| * IPv6 tethering doesn't need the state-based conntrack rules, so |
| * it unconditionally jumps to the tether counters chain all the time. |
| */ |
| std::vector<std::string> v6Cmds = { |
| "*filter", |
| StringPrintf("-A %s -g %s", LOCAL_FORWARD, LOCAL_TETHER_COUNTERS_CHAIN), |
| "COMMIT\n" |
| }; |
| |
| return iptablesRestoreFunction(V6, Join(v6Cmds, '\n'), nullptr); |
| } |
| |
| // Gets a pointer to the ForwardingDownstream for an interface pair in the map, or nullptr |
| TetherController::ForwardingDownstream* TetherController::findForwardingDownstream( |
| const std::string& intIface, const std::string& extIface) { |
| auto extIfaceMatches = mFwdIfaces.equal_range(extIface); |
| for (auto it = extIfaceMatches.first; it != extIfaceMatches.second; ++it) { |
| if (it->second.iface == intIface) { |
| return &(it->second); |
| } |
| } |
| return nullptr; |
| } |
| |
| void TetherController::addForwardingPair(const std::string& intIface, const std::string& extIface) { |
| ForwardingDownstream* existingEntry = findForwardingDownstream(intIface, extIface); |
| if (existingEntry != nullptr) { |
| existingEntry->active = true; |
| return; |
| } |
| |
| mFwdIfaces.insert(std::pair<std::string, ForwardingDownstream>(extIface, { |
| .iface = intIface, |
| .active = true |
| })); |
| } |
| |
| void TetherController::markForwardingPairDisabled( |
| const std::string& intIface, const std::string& extIface) { |
| ForwardingDownstream* existingEntry = findForwardingDownstream(intIface, extIface); |
| if (existingEntry == nullptr) { |
| return; |
| } |
| |
| existingEntry->active = false; |
| } |
| |
| bool TetherController::isForwardingPairEnabled( |
| const std::string& intIface, const std::string& extIface) { |
| ForwardingDownstream* existingEntry = findForwardingDownstream(intIface, extIface); |
| return existingEntry != nullptr && existingEntry->active; |
| } |
| |
| bool TetherController::isAnyForwardingEnabledOnUpstream(const std::string& extIface) { |
| auto extIfaceMatches = mFwdIfaces.equal_range(extIface); |
| for (auto it = extIfaceMatches.first; it != extIfaceMatches.second; ++it) { |
| if (it->second.active) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool TetherController::isAnyForwardingPairEnabled() { |
| for (auto& it : mFwdIfaces) { |
| if (it.second.active) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| bool TetherController::tetherCountingRuleExists( |
| const std::string& iface1, const std::string& iface2) { |
| // A counting rule exists if NAT was ever enabled for this interface pair, so if the pair |
| // is in the map regardless of its active status. Rules are added both ways so we check with |
| // the 2 combinations. |
| return findForwardingDownstream(iface1, iface2) != nullptr |
| || findForwardingDownstream(iface2, iface1) != nullptr; |
| } |
| |
| /* static */ |
| std::string TetherController::makeTetherCountingRule(const char *if1, const char *if2) { |
| return StringPrintf("-A %s -i %s -o %s -j RETURN", LOCAL_TETHER_COUNTERS_CHAIN, if1, if2); |
| } |
| |
| int TetherController::setForwardRules(bool add, const char *intIface, const char *extIface) { |
| const char *op = add ? "-A" : "-D"; |
| |
| std::string rpfilterCmd = StringPrintf( |
| "*raw\n" |
| "%s %s -i %s -m rpfilter --invert ! -s fe80::/64 -j DROP\n" |
| "COMMIT\n", op, LOCAL_RAW_PREROUTING, intIface); |
| if (iptablesRestoreFunction(V6, rpfilterCmd, nullptr) == -1 && add) { |
| return -1; |
| } |
| |
| std::vector<std::string> v4 = { |
| "*raw", |
| StringPrintf("%s %s -p tcp --dport 21 -i %s -j CT --helper ftp", |
| op, LOCAL_RAW_PREROUTING, intIface), |
| "COMMIT", |
| "*filter", |
| StringPrintf("%s %s -i %s -o %s -m state --state ESTABLISHED,RELATED -g %s", |
| op, LOCAL_FORWARD, extIface, intIface, LOCAL_TETHER_COUNTERS_CHAIN), |
| StringPrintf("%s %s -i %s -o %s -m state --state INVALID -j DROP", |
| op, LOCAL_FORWARD, intIface, extIface), |
| StringPrintf("%s %s -i %s -o %s -g %s", |
| op, LOCAL_FORWARD, intIface, extIface, LOCAL_TETHER_COUNTERS_CHAIN), |
| }; |
| |
| std::vector<std::string> v6 = { |
| "*filter", |
| }; |
| |
| // We only ever add tethering quota rules so that they stick. |
| if (add && !tetherCountingRuleExists(intIface, extIface)) { |
| v4.push_back(makeTetherCountingRule(intIface, extIface)); |
| v4.push_back(makeTetherCountingRule(extIface, intIface)); |
| v6.push_back(makeTetherCountingRule(intIface, extIface)); |
| v6.push_back(makeTetherCountingRule(extIface, intIface)); |
| } |
| |
| // Always make sure the drop rule is at the end. |
| // TODO: instead of doing this, consider just rebuilding LOCAL_FORWARD completely from scratch |
| // every time, starting with ":tetherctrl_FORWARD -\n". This would likely be a bit simpler. |
| if (add) { |
| v4.push_back(StringPrintf("-D %s -j DROP", LOCAL_FORWARD)); |
| v4.push_back(StringPrintf("-A %s -j DROP", LOCAL_FORWARD)); |
| } |
| |
| v4.push_back("COMMIT\n"); |
| v6.push_back("COMMIT\n"); |
| |
| // We only add IPv6 rules here, never remove them. |
| if (iptablesRestoreFunction(V4, Join(v4, '\n'), nullptr) == -1 || |
| (add && iptablesRestoreFunction(V6, Join(v6, '\n'), nullptr) == -1)) { |
| // unwind what's been done, but don't care about success - what more could we do? |
| if (add) { |
| setForwardRules(false, intIface, extIface); |
| } |
| return -1; |
| } |
| |
| if (add) { |
| addForwardingPair(intIface, extIface); |
| } else { |
| markForwardingPairDisabled(intIface, extIface); |
| } |
| |
| return 0; |
| } |
| |
| int TetherController::disableNat(const char* intIface, const char* extIface) { |
| if (!isIfaceName(intIface) || !isIfaceName(extIface)) { |
| errno = ENODEV; |
| return -1; |
| } |
| |
| setForwardRules(false, intIface, extIface); |
| if (!isAnyForwardingPairEnabled()) { |
| setDefaults(); |
| } |
| return 0; |
| } |
| |
| void TetherController::addStats(TetherStatsList& statsList, const TetherStats& stats) { |
| for (TetherStats& existing : statsList) { |
| if (existing.addStatsIfMatch(stats)) { |
| return; |
| } |
| } |
| // No match. Insert a new interface pair. |
| statsList.push_back(stats); |
| } |
| |
| /* |
| * Parse the ptks and bytes out of: |
| * Chain tetherctrl_counters (4 references) |
| * pkts bytes target prot opt in out source destination |
| * 26 2373 RETURN all -- wlan0 rmnet0 0.0.0.0/0 0.0.0.0/0 |
| * 27 2002 RETURN all -- rmnet0 wlan0 0.0.0.0/0 0.0.0.0/0 |
| * 1040 107471 RETURN all -- bt-pan rmnet0 0.0.0.0/0 0.0.0.0/0 |
| * 1450 1708806 RETURN all -- rmnet0 bt-pan 0.0.0.0/0 0.0.0.0/0 |
| * or: |
| * Chain tetherctrl_counters (0 references) |
| * pkts bytes target prot opt in out source destination |
| * 0 0 RETURN all wlan0 rmnet_data0 ::/0 ::/0 |
| * 0 0 RETURN all rmnet_data0 wlan0 ::/0 ::/0 |
| * |
| */ |
| int TetherController::addForwardChainStats(TetherStatsList& statsList, |
| const std::string& statsOutput, |
| std::string &extraProcessingInfo) { |
| int res; |
| std::string statsLine; |
| char iface0[MAX_IPT_OUTPUT_LINE_LEN]; |
| char iface1[MAX_IPT_OUTPUT_LINE_LEN]; |
| char rest[MAX_IPT_OUTPUT_LINE_LEN]; |
| |
| TetherStats stats; |
| const TetherStats empty; |
| const char *buffPtr; |
| int64_t packets, bytes; |
| |
| std::stringstream stream(statsOutput); |
| |
| // Skip headers. |
| for (int i = 0; i < 2; i++) { |
| std::getline(stream, statsLine, '\n'); |
| extraProcessingInfo += statsLine + "\n"; |
| if (statsLine.empty()) { |
| ALOGE("Empty header while parsing tethering stats"); |
| return -EREMOTEIO; |
| } |
| } |
| |
| while (std::getline(stream, statsLine, '\n')) { |
| buffPtr = statsLine.c_str(); |
| |
| /* Clean up, so a failed parse can still print info */ |
| iface0[0] = iface1[0] = rest[0] = packets = bytes = 0; |
| if (strstr(buffPtr, "0.0.0.0")) { |
| // IPv4 has -- indicating what to do with fragments... |
| // 26 2373 RETURN all -- wlan0 rmnet0 0.0.0.0/0 0.0.0.0/0 |
| res = sscanf(buffPtr, "%" SCNd64" %" SCNd64" RETURN all -- %s %s 0.%s", |
| &packets, &bytes, iface0, iface1, rest); |
| } else { |
| // ... but IPv6 does not. |
| // 26 2373 RETURN all wlan0 rmnet0 ::/0 ::/0 |
| res = sscanf(buffPtr, "%" SCNd64" %" SCNd64" RETURN all %s %s ::/%s", |
| &packets, &bytes, iface0, iface1, rest); |
| } |
| ALOGV("parse res=%d iface0=<%s> iface1=<%s> pkts=%" PRId64" bytes=%" PRId64" rest=<%s> orig line=<%s>", res, |
| iface0, iface1, packets, bytes, rest, buffPtr); |
| extraProcessingInfo += buffPtr; |
| extraProcessingInfo += "\n"; |
| |
| if (res != 5) { |
| return -EREMOTEIO; |
| } |
| /* |
| * The following assumes that the 1st rule has in:extIface out:intIface, |
| * which is what TetherController sets up. |
| * The 1st matches rx, and sets up the pair for the tx side. |
| */ |
| if (!stats.intIface[0]) { |
| ALOGV("0Filter RX iface_in=%s iface_out=%s rx_bytes=%" PRId64" rx_packets=%" PRId64" ", iface0, iface1, bytes, packets); |
| stats.intIface = iface0; |
| stats.extIface = iface1; |
| stats.txPackets = packets; |
| stats.txBytes = bytes; |
| } else if (stats.intIface == iface1 && stats.extIface == iface0) { |
| ALOGV("0Filter TX iface_in=%s iface_out=%s rx_bytes=%" PRId64" rx_packets=%" PRId64" ", iface0, iface1, bytes, packets); |
| stats.rxPackets = packets; |
| stats.rxBytes = bytes; |
| } |
| if (stats.rxBytes != -1 && stats.txBytes != -1) { |
| ALOGV("rx_bytes=%" PRId64" tx_bytes=%" PRId64, stats.rxBytes, stats.txBytes); |
| addStats(statsList, stats); |
| stats = empty; |
| } |
| } |
| |
| /* It is always an error to find only one side of the stats. */ |
| if (((stats.rxBytes == -1) != (stats.txBytes == -1))) { |
| return -EREMOTEIO; |
| } |
| return 0; |
| } |
| |
| StatusOr<TetherController::TetherStatsList> TetherController::getTetherStats() { |
| TetherStatsList statsList; |
| std::string parsedIptablesOutput; |
| |
| for (const IptablesTarget target : {V4, V6}) { |
| std::string statsString; |
| if (int ret = iptablesRestoreFunction(target, GET_TETHER_STATS_COMMAND, &statsString)) { |
| return statusFromErrno(-ret, StringPrintf("failed to fetch tether stats (%d): %d", |
| target, ret)); |
| } |
| |
| if (int ret = addForwardChainStats(statsList, statsString, parsedIptablesOutput)) { |
| return statusFromErrno(-ret, StringPrintf("failed to parse %s tether stats:\n%s", |
| target == V4 ? "IPv4": "IPv6", |
| parsedIptablesOutput.c_str())); |
| } |
| } |
| |
| return statsList; |
| } |
| |
| } // namespace net |
| } // namespace android |