/*
* Copyright (C) 2011 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_NDEBUG 0
/*
* The CommandListener, FrameworkListener don't allow for
* multiple calls in parallel to reach the BandwidthController.
* If they ever were to allow it, then netd/ would need some tweaking.
*/
#include <string>
#include <vector>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#define __STDC_FORMAT_MACROS 1
#include <inttypes.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/pkt_sched.h>
#include "android-base/stringprintf.h"
#include "android-base/strings.h"
#define LOG_TAG "BandwidthController"
#include <cutils/log.h>
#include <cutils/properties.h>
#include <logwrap/logwrap.h>
#include "NetdConstants.h"
#include "BandwidthController.h"
#include "NatController.h" /* For LOCAL_TETHER_COUNTERS_CHAIN */
#include "ResponseCode.h"
/* Alphabetical */
#define ALERT_IPT_TEMPLATE "%s %s -m quota2 ! --quota %" PRId64" --name %s"
const char* BandwidthController::LOCAL_INPUT = "bw_INPUT";
const char* BandwidthController::LOCAL_FORWARD = "bw_FORWARD";
const char* BandwidthController::LOCAL_OUTPUT = "bw_OUTPUT";
const char* BandwidthController::LOCAL_RAW_PREROUTING = "bw_raw_PREROUTING";
const char* BandwidthController::LOCAL_MANGLE_POSTROUTING = "bw_mangle_POSTROUTING";
auto BandwidthController::execFunction = android_fork_execvp;
auto BandwidthController::popenFunction = popen;
auto BandwidthController::iptablesRestoreFunction = execIptablesRestore;
namespace {
const char ALERT_GLOBAL_NAME[] = "globalAlert";
const int MAX_CMD_ARGS = 32;
const int MAX_CMD_LEN = 1024;
const int MAX_IFACENAME_LEN = 64;
const int MAX_IPT_OUTPUT_LINE_LEN = 256;
/**
* Some comments about the rules:
* * Ordering
* - when an interface is marked as costly it should be INSERTED into the INPUT/OUTPUT chains.
* E.g. "-I bw_INPUT -i rmnet0 --jump costly"
* - quota'd rules in the costly chain should be before bw_penalty_box lookups.
* - the qtaguid counting is done at the end of the bw_INPUT/bw_OUTPUT user chains.
*
* * global quota vs per interface quota
* - global quota for all costly interfaces uses a single costly chain:
* . initial rules
* iptables -N bw_costly_shared
* iptables -I bw_INPUT -i iface0 --jump bw_costly_shared
* iptables -I bw_OUTPUT -o iface0 --jump bw_costly_shared
* iptables -I bw_costly_shared -m quota \! --quota 500000 \
* --jump REJECT --reject-with icmp-net-prohibited
* iptables -A bw_costly_shared --jump bw_penalty_box
* iptables -A bw_penalty_box --jump bw_happy_box
* iptables -A bw_happy_box --jump bw_data_saver
*
* . adding a new iface to this, E.g.:
* iptables -I bw_INPUT -i iface1 --jump bw_costly_shared
* iptables -I bw_OUTPUT -o iface1 --jump bw_costly_shared
*
* - quota per interface. This is achieve by having "costly" chains per quota.
* E.g. adding a new costly interface iface0 with its own quota:
* iptables -N bw_costly_iface0
* iptables -I bw_INPUT -i iface0 --jump bw_costly_iface0
* iptables -I bw_OUTPUT -o iface0 --jump bw_costly_iface0
* iptables -A bw_costly_iface0 -m quota \! --quota 500000 \
* --jump REJECT --reject-with icmp-port-unreachable
* iptables -A bw_costly_iface0 --jump bw_penalty_box
*
* * Penalty box, happy box and data saver.
* - bw_penalty box is a blacklist of apps that are rejected.
* - bw_happy_box is a whitelist of apps. It always includes all system apps
* - bw_data_saver implements data usage restrictions.
* - Via the UI the user can add and remove apps from the whitelist and
* blacklist, and turn on/off data saver.
* - The blacklist takes precedence over the whitelist and the whitelist
* takes precedence over data saver.
*
* * bw_penalty_box handling:
* - only one bw_penalty_box for all interfaces
* E.g Adding an app:
* iptables -I bw_penalty_box -m owner --uid-owner app_3 \
* --jump REJECT --reject-with icmp-port-unreachable
*
* * bw_happy_box handling:
* - The bw_happy_box comes after the penalty box.
* E.g Adding a happy app,
* iptables -I bw_happy_box -m owner --uid-owner app_3 \
* --jump RETURN
*
* * bw_data_saver handling:
* - The bw_data_saver comes after the happy box.
* Enable data saver:
* iptables -R 1 bw_data_saver --jump REJECT --reject-with icmp-port-unreachable
* Disable data saver:
* iptables -R 1 bw_data_saver --jump RETURN
*/
const std::string COMMIT_AND_CLOSE = "COMMIT\n\x04";
const std::string DATA_SAVER_ENABLE_COMMAND = "-R bw_data_saver 1";
const std::string HAPPY_BOX_WHITELIST_COMMAND = android::base::StringPrintf(
"-I bw_happy_box -m owner --uid-owner %d-%d --jump RETURN", 0, MAX_SYSTEM_UID);
static const std::vector<std::string> IPT_FLUSH_COMMANDS = {
/*
* Cleanup rules.
* Should normally include bw_costly_<iface>, but we rely on the way they are setup
* to allow coexistance.
*/
"*filter",
":bw_INPUT -",
":bw_OUTPUT -",
":bw_FORWARD -",
":bw_happy_box -",
":bw_penalty_box -",
":bw_data_saver -",
":bw_costly_shared -",
"COMMIT",
"*raw",
":bw_raw_PREROUTING -",
"COMMIT",
"*mangle",
":bw_mangle_POSTROUTING -",
COMMIT_AND_CLOSE
};
static const std::vector<std::string> IPT_BASIC_ACCOUNTING_COMMANDS = {
"*filter",
"-A bw_INPUT -m owner --socket-exists", /* This is a tracking rule. */
"-A bw_OUTPUT -m owner --socket-exists", /* This is a tracking rule. */
"-A bw_costly_shared --jump bw_penalty_box",
"-A bw_penalty_box --jump bw_happy_box",
"-A bw_happy_box --jump bw_data_saver",
"-A bw_data_saver -j RETURN",
HAPPY_BOX_WHITELIST_COMMAND,
"COMMIT",
"*raw",
"-A bw_raw_PREROUTING -m owner --socket-exists", /* This is a tracking rule. */
"COMMIT",
"*mangle",
"-A bw_mangle_POSTROUTING -m owner --socket-exists", /* This is a tracking rule. */
COMMIT_AND_CLOSE
};
} // namespace
BandwidthController::BandwidthController(void) {
}
int BandwidthController::runIpxtablesCmd(const char *cmd, IptJumpOp jumpHandling,
IptFailureLog failureHandling) {
int res = 0;
ALOGV("runIpxtablesCmd(cmd=%s)", cmd);
res |= runIptablesCmd(cmd, jumpHandling, IptIpV4, failureHandling);
res |= runIptablesCmd(cmd, jumpHandling, IptIpV6, failureHandling);
return res;
}
int BandwidthController::StrncpyAndCheck(char *buffer, const char *src, size_t buffSize) {
memset(buffer, '\0', buffSize); // strncpy() is not filling leftover with '\0'
strncpy(buffer, src, buffSize);
return buffer[buffSize - 1];
}
int BandwidthController::runIptablesCmd(const char *cmd, IptJumpOp jumpHandling,
IptIpVer iptVer, IptFailureLog failureHandling) {
char buffer[MAX_CMD_LEN];
const char *argv[MAX_CMD_ARGS];
int argc = 0;
char *next = buffer;
char *tmp;
int res;
int status = 0;
std::string fullCmd = cmd;
switch (jumpHandling) {
case IptJumpReject:
/*
* Must be carefull what one rejects with, as uper layer protocols will just
* keep on hammering the device until the number of retries are done.
* For port-unreachable (default), TCP should consider as an abort (RFC1122).
*/
fullCmd += " --jump REJECT";
break;
case IptJumpReturn:
fullCmd += " --jump RETURN";
break;
case IptJumpNoAdd:
break;
}
fullCmd.insert(0, " -w ");
fullCmd.insert(0, iptVer == IptIpV4 ? IPTABLES_PATH : IP6TABLES_PATH);
if (StrncpyAndCheck(buffer, fullCmd.c_str(), sizeof(buffer))) {
ALOGE("iptables command too long");
return -1;
}
argc = 0;
while ((tmp = strsep(&next, " "))) {
argv[argc++] = tmp;
if (argc >= MAX_CMD_ARGS) {
ALOGE("iptables argument overflow");
return -1;
}
}
argv[argc] = NULL;
res = execFunction(argc, (char **)argv, &status, false,
failureHandling == IptFailShow);
res = res || !WIFEXITED(status) || WEXITSTATUS(status);
if (res && failureHandling == IptFailShow) {
ALOGE("runIptablesCmd(): res=%d status=%d failed %s", res, status,
fullCmd.c_str());
}
return res;
}
void BandwidthController::flushCleanTables(bool doClean) {
/* Flush and remove the bw_costly_<iface> tables */
flushExistingCostlyTables(doClean);
std::string commands = android::base::Join(IPT_FLUSH_COMMANDS, '\n');
iptablesRestoreFunction(V4V6, commands);
}
int BandwidthController::setupIptablesHooks(void) {
/* flush+clean is allowed to fail */
flushCleanTables(true);
return 0;
}
int BandwidthController::enableBandwidthControl(bool force) {
char value[PROPERTY_VALUE_MAX];
if (!force) {
property_get("persist.bandwidth.enable", value, "1");
if (!strcmp(value, "0"))
return 0;
}
/* Let's pretend we started from scratch ... */
sharedQuotaIfaces.clear();
quotaIfaces.clear();
globalAlertBytes = 0;
globalAlertTetherCount = 0;
sharedQuotaBytes = sharedAlertBytes = 0;
flushCleanTables(false);
std::string commands = android::base::Join(IPT_BASIC_ACCOUNTING_COMMANDS, '\n');
return iptablesRestoreFunction(V4V6, commands);
}
int BandwidthController::disableBandwidthControl(void) {
flushCleanTables(false);
return 0;
}
int BandwidthController::enableDataSaver(bool enable) {
return runIpxtablesCmd(DATA_SAVER_ENABLE_COMMAND.c_str(),
enable ? IptJumpReject : IptJumpReturn, IptFailShow);
}
int BandwidthController::runCommands(int numCommands, const char *commands[],
RunCmdErrHandling cmdErrHandling) {
int res = 0;
IptFailureLog failureLogging = IptFailShow;
if (cmdErrHandling == RunCmdFailureOk) {
failureLogging = IptFailHide;
}
ALOGV("runCommands(): %d commands", numCommands);
for (int cmdNum = 0; cmdNum < numCommands; cmdNum++) {
res = runIpxtablesCmd(commands[cmdNum], IptJumpNoAdd, failureLogging);
if (res && cmdErrHandling != RunCmdFailureOk)
return res;
}
return 0;
}
std::string BandwidthController::makeIptablesSpecialAppCmd(IptOp op, int uid, const char *chain) {
std::string res;
char *buff;
const char *opFlag;
switch (op) {
case IptOpInsert:
opFlag = "-I";
break;
case IptOpAppend:
ALOGE("Append op not supported for %s uids", chain);
res = "";
return res;
break;
case IptOpReplace:
opFlag = "-R";
break;
default:
case IptOpDelete:
opFlag = "-D";
break;
}
asprintf(&buff, "%s %s -m owner --uid-owner %d", opFlag, chain, uid);
res = buff;
free(buff);
return res;
}
int BandwidthController::addNaughtyApps(int numUids, char *appUids[]) {
return manipulateNaughtyApps(numUids, appUids, SpecialAppOpAdd);
}
int BandwidthController::removeNaughtyApps(int numUids, char *appUids[]) {
return manipulateNaughtyApps(numUids, appUids, SpecialAppOpRemove);
}
int BandwidthController::addNiceApps(int numUids, char *appUids[]) {
return manipulateNiceApps(numUids, appUids, SpecialAppOpAdd);
}
int BandwidthController::removeNiceApps(int numUids, char *appUids[]) {
return manipulateNiceApps(numUids, appUids, SpecialAppOpRemove);
}
int BandwidthController::manipulateNaughtyApps(int numUids, char *appStrUids[], SpecialAppOp appOp) {
return manipulateSpecialApps(numUids, appStrUids, "bw_penalty_box", IptJumpReject, appOp);
}
int BandwidthController::manipulateNiceApps(int numUids, char *appStrUids[], SpecialAppOp appOp) {
return manipulateSpecialApps(numUids, appStrUids, "bw_happy_box", IptJumpReturn, appOp);
}
int BandwidthController::manipulateSpecialApps(int numUids, char *appStrUids[],
const char *chain,
IptJumpOp jumpHandling, SpecialAppOp appOp) {
int uidNum;
const char *failLogTemplate;
IptOp op;
int appUids[numUids];
std::string iptCmd;
switch (appOp) {
case SpecialAppOpAdd:
op = IptOpInsert;
failLogTemplate = "Failed to add app uid %s(%d) to %s.";
break;
case SpecialAppOpRemove:
op = IptOpDelete;
failLogTemplate = "Failed to delete app uid %s(%d) from %s box.";
break;
default:
ALOGE("Unexpected app Op %d", appOp);
return -1;
}
for (uidNum = 0; uidNum < numUids; uidNum++) {
char *end;
appUids[uidNum] = strtoul(appStrUids[uidNum], &end, 0);
if (*end || !*appStrUids[uidNum]) {
ALOGE(failLogTemplate, appStrUids[uidNum], appUids[uidNum], chain);
goto fail_parse;
}
}
for (uidNum = 0; uidNum < numUids; uidNum++) {
int uid = appUids[uidNum];
iptCmd = makeIptablesSpecialAppCmd(op, uid, chain);
if (runIpxtablesCmd(iptCmd.c_str(), jumpHandling)) {
ALOGE(failLogTemplate, appStrUids[uidNum], uid, chain);
goto fail_with_uidNum;
}
}
return 0;
fail_with_uidNum:
/* Try to remove the uid that failed in any case*/
iptCmd = makeIptablesSpecialAppCmd(IptOpDelete, appUids[uidNum], chain);
runIpxtablesCmd(iptCmd.c_str(), jumpHandling);
fail_parse:
return -1;
}
std::string BandwidthController::makeIptablesQuotaCmd(IptOp op, const char *costName, int64_t quota) {
std::string res;
char *buff;
const char *opFlag;
ALOGV("makeIptablesQuotaCmd(%d, %" PRId64")", op, quota);
switch (op) {
case IptOpInsert:
opFlag = "-I";
break;
case IptOpAppend:
opFlag = "-A";
break;
case IptOpReplace:
opFlag = "-R";
break;
default:
case IptOpDelete:
opFlag = "-D";
break;
}
// The requried IP version specific --jump REJECT ... will be added later.
asprintf(&buff, "%s bw_costly_%s -m quota2 ! --quota %" PRId64" --name %s", opFlag, costName, quota,
costName);
res = buff;
free(buff);
return res;
}
int BandwidthController::prepCostlyIface(const char *ifn, QuotaType quotaType) {
char cmd[MAX_CMD_LEN];
int res = 0, res1, res2;
int ruleInsertPos = 1;
std::string costString;
const char *costCString;
/* The "-N costly" is created upfront, no need to handle it here. */
switch (quotaType) {
case QuotaUnique:
costString = "bw_costly_";
costString += ifn;
costCString = costString.c_str();
/*
* Flush the bw_costly_<iface> is allowed to fail in case it didn't exist.
* Creating a new one is allowed to fail in case it existed.
* This helps with netd restarts.
*/
snprintf(cmd, sizeof(cmd), "-F %s", costCString);
res1 = runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
snprintf(cmd, sizeof(cmd), "-N %s", costCString);
res2 = runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
res = (res1 && res2) || (!res1 && !res2);
snprintf(cmd, sizeof(cmd), "-A %s -j bw_penalty_box", costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
break;
case QuotaShared:
costCString = "bw_costly_shared";
break;
default:
ALOGE("Unexpected quotatype %d", quotaType);
return -1;
}
if (globalAlertBytes) {
/* The alert rule comes 1st */
ruleInsertPos = 2;
}
snprintf(cmd, sizeof(cmd), "-D bw_INPUT -i %s --jump %s", ifn, costCString);
runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
snprintf(cmd, sizeof(cmd), "-I bw_INPUT %d -i %s --jump %s", ruleInsertPos, ifn, costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
snprintf(cmd, sizeof(cmd), "-D bw_OUTPUT -o %s --jump %s", ifn, costCString);
runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
snprintf(cmd, sizeof(cmd), "-I bw_OUTPUT %d -o %s --jump %s", ruleInsertPos, ifn, costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
snprintf(cmd, sizeof(cmd), "-D bw_FORWARD -o %s --jump %s", ifn, costCString);
runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
snprintf(cmd, sizeof(cmd), "-A bw_FORWARD -o %s --jump %s", ifn, costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
return res;
}
int BandwidthController::cleanupCostlyIface(const char *ifn, QuotaType quotaType) {
char cmd[MAX_CMD_LEN];
int res = 0;
std::string costString;
const char *costCString;
switch (quotaType) {
case QuotaUnique:
costString = "bw_costly_";
costString += ifn;
costCString = costString.c_str();
break;
case QuotaShared:
costCString = "bw_costly_shared";
break;
default:
ALOGE("Unexpected quotatype %d", quotaType);
return -1;
}
snprintf(cmd, sizeof(cmd), "-D bw_INPUT -i %s --jump %s", ifn, costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
for (const auto tableName : {LOCAL_OUTPUT, LOCAL_FORWARD}) {
snprintf(cmd, sizeof(cmd), "-D %s -o %s --jump %s", tableName, ifn, costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
}
/* The "-N bw_costly_shared" is created upfront, no need to handle it here. */
if (quotaType == QuotaUnique) {
snprintf(cmd, sizeof(cmd), "-F %s", costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
snprintf(cmd, sizeof(cmd), "-X %s", costCString);
res |= runIpxtablesCmd(cmd, IptJumpNoAdd);
}
return res;
}
int BandwidthController::setInterfaceSharedQuota(const char *iface, int64_t maxBytes) {
char ifn[MAX_IFACENAME_LEN];
int res = 0;
std::string quotaCmd;
std::string ifaceName;
;
const char *costName = "shared";
std::list<std::string>::iterator it;
if (!maxBytes) {
/* Don't talk about -1, deprecate it. */
ALOGE("Invalid bytes value. 1..max_int64.");
return -1;
}
if (!isIfaceName(iface))
return -1;
if (StrncpyAndCheck(ifn, iface, sizeof(ifn))) {
ALOGE("Interface name longer than %d", MAX_IFACENAME_LEN);
return -1;
}
ifaceName = ifn;
if (maxBytes == -1) {
return removeInterfaceSharedQuota(ifn);
}
/* Insert ingress quota. */
for (it = sharedQuotaIfaces.begin(); it != sharedQuotaIfaces.end(); it++) {
if (*it == ifaceName)
break;
}
if (it == sharedQuotaIfaces.end()) {
res |= prepCostlyIface(ifn, QuotaShared);
if (sharedQuotaIfaces.empty()) {
quotaCmd = makeIptablesQuotaCmd(IptOpInsert, costName, maxBytes);
res |= runIpxtablesCmd(quotaCmd.c_str(), IptJumpReject);
if (res) {
ALOGE("Failed set quota rule");
goto fail;
}
sharedQuotaBytes = maxBytes;
}
sharedQuotaIfaces.push_front(ifaceName);
}
if (maxBytes != sharedQuotaBytes) {
res |= updateQuota(costName, maxBytes);
if (res) {
ALOGE("Failed update quota for %s", costName);
goto fail;
}
sharedQuotaBytes = maxBytes;
}
return 0;
fail:
/*
* TODO(jpa): once we get rid of iptables in favor of rtnetlink, reparse
* rules in the kernel to see which ones need cleaning up.
* For now callers needs to choose if they want to "ndc bandwidth enable"
* which resets everything.
*/
removeInterfaceSharedQuota(ifn);
return -1;
}
/* It will also cleanup any shared alerts */
int BandwidthController::removeInterfaceSharedQuota(const char *iface) {
char ifn[MAX_IFACENAME_LEN];
int res = 0;
std::string ifaceName;
std::list<std::string>::iterator it;
const char *costName = "shared";
if (!isIfaceName(iface))
return -1;
if (StrncpyAndCheck(ifn, iface, sizeof(ifn))) {
ALOGE("Interface name longer than %d", MAX_IFACENAME_LEN);
return -1;
}
ifaceName = ifn;
for (it = sharedQuotaIfaces.begin(); it != sharedQuotaIfaces.end(); it++) {
if (*it == ifaceName)
break;
}
if (it == sharedQuotaIfaces.end()) {
ALOGE("No such iface %s to delete", ifn);
return -1;
}
res |= cleanupCostlyIface(ifn, QuotaShared);
sharedQuotaIfaces.erase(it);
if (sharedQuotaIfaces.empty()) {
std::string quotaCmd;
quotaCmd = makeIptablesQuotaCmd(IptOpDelete, costName, sharedQuotaBytes);
res |= runIpxtablesCmd(quotaCmd.c_str(), IptJumpReject);
sharedQuotaBytes = 0;
if (sharedAlertBytes) {
removeSharedAlert();
sharedAlertBytes = 0;
}
}
return res;
}
int BandwidthController::setInterfaceQuota(const char *iface, int64_t maxBytes) {
char ifn[MAX_IFACENAME_LEN];
int res = 0;
std::string ifaceName;
const char *costName;
std::list<QuotaInfo>::iterator it;
std::string quotaCmd;
if (!isIfaceName(iface))
return -1;
if (!maxBytes) {
/* Don't talk about -1, deprecate it. */
ALOGE("Invalid bytes value. 1..max_int64.");
return -1;
}
if (maxBytes == -1) {
return removeInterfaceQuota(iface);
}
if (StrncpyAndCheck(ifn, iface, sizeof(ifn))) {
ALOGE("Interface name longer than %d", MAX_IFACENAME_LEN);
return -1;
}
ifaceName = ifn;
costName = iface;
/* Insert ingress quota. */
for (it = quotaIfaces.begin(); it != quotaIfaces.end(); it++) {
if (it->ifaceName == ifaceName)
break;
}
if (it == quotaIfaces.end()) {
/* Preparing the iface adds a penalty/happy box check */
res |= prepCostlyIface(ifn, QuotaUnique);
/*
* The rejecting quota limit should go after the penalty/happy box checks
* or else a naughty app could just eat up the quota.
* So we append here.
*/
quotaCmd = makeIptablesQuotaCmd(IptOpAppend, costName, maxBytes);
res |= runIpxtablesCmd(quotaCmd.c_str(), IptJumpReject);
if (res) {
ALOGE("Failed set quota rule");
goto fail;
}
quotaIfaces.push_front(QuotaInfo(ifaceName, maxBytes, 0));
} else {
res |= updateQuota(costName, maxBytes);
if (res) {
ALOGE("Failed update quota for %s", iface);
goto fail;
}
it->quota = maxBytes;
}
return 0;
fail:
/*
* TODO(jpa): once we get rid of iptables in favor of rtnetlink, reparse
* rules in the kernel to see which ones need cleaning up.
* For now callers needs to choose if they want to "ndc bandwidth enable"
* which resets everything.
*/
removeInterfaceSharedQuota(ifn);
return -1;
}
int BandwidthController::getInterfaceSharedQuota(int64_t *bytes) {
return getInterfaceQuota("shared", bytes);
}
int BandwidthController::getInterfaceQuota(const char *costName, int64_t *bytes) {
FILE *fp;
char *fname;
int scanRes;
if (!isIfaceName(costName))
return -1;
asprintf(&fname, "/proc/net/xt_quota/%s", costName);
fp = fopen(fname, "re");
free(fname);
if (!fp) {
ALOGE("Reading quota %s failed (%s)", costName, strerror(errno));
return -1;
}
scanRes = fscanf(fp, "%" SCNd64, bytes);
ALOGV("Read quota res=%d bytes=%" PRId64, scanRes, *bytes);
fclose(fp);
return scanRes == 1 ? 0 : -1;
}
int BandwidthController::removeInterfaceQuota(const char *iface) {
char ifn[MAX_IFACENAME_LEN];
int res = 0;
std::string ifaceName;
std::list<QuotaInfo>::iterator it;
if (!isIfaceName(iface))
return -1;
if (StrncpyAndCheck(ifn, iface, sizeof(ifn))) {
ALOGE("Interface name longer than %d", MAX_IFACENAME_LEN);
return -1;
}
ifaceName = ifn;
for (it = quotaIfaces.begin(); it != quotaIfaces.end(); it++) {
if (it->ifaceName == ifaceName)
break;
}
if (it == quotaIfaces.end()) {
ALOGE("No such iface %s to delete", ifn);
return -1;
}
/* This also removes the quota command of CostlyIface chain. */
res |= cleanupCostlyIface(ifn, QuotaUnique);
quotaIfaces.erase(it);
return res;
}
int BandwidthController::updateQuota(const char *quotaName, int64_t bytes) {
FILE *fp;
char *fname;
if (!isIfaceName(quotaName)) {
ALOGE("updateQuota: Invalid quotaName \"%s\"", quotaName);
return -1;
}
asprintf(&fname, "/proc/net/xt_quota/%s", quotaName);
fp = fopen(fname, "we");
free(fname);
if (!fp) {
ALOGE("Updating quota %s failed (%s)", quotaName, strerror(errno));
return -1;
}
fprintf(fp, "%" PRId64"\n", bytes);
fclose(fp);
return 0;
}
int BandwidthController::runIptablesAlertCmd(IptOp op, const char *alertName, int64_t bytes) {
int res = 0;
const char *opFlag;
char *alertQuotaCmd;
switch (op) {
case IptOpInsert:
opFlag = "-I";
break;
case IptOpAppend:
opFlag = "-A";
break;
case IptOpReplace:
opFlag = "-R";
break;
default:
case IptOpDelete:
opFlag = "-D";
break;
}
asprintf(&alertQuotaCmd, ALERT_IPT_TEMPLATE, opFlag, "bw_INPUT",
bytes, alertName);
res |= runIpxtablesCmd(alertQuotaCmd, IptJumpNoAdd);
free(alertQuotaCmd);
asprintf(&alertQuotaCmd, ALERT_IPT_TEMPLATE, opFlag, "bw_OUTPUT",
bytes, alertName);
res |= runIpxtablesCmd(alertQuotaCmd, IptJumpNoAdd);
free(alertQuotaCmd);
return res;
}
int BandwidthController::runIptablesAlertFwdCmd(IptOp op, const char *alertName, int64_t bytes) {
int res = 0;
const char *opFlag;
char *alertQuotaCmd;
switch (op) {
case IptOpInsert:
opFlag = "-I";
break;
case IptOpAppend:
opFlag = "-A";
break;
case IptOpReplace:
opFlag = "-R";
break;
default:
case IptOpDelete:
opFlag = "-D";
break;
}
asprintf(&alertQuotaCmd, ALERT_IPT_TEMPLATE, opFlag, "bw_FORWARD",
bytes, alertName);
res = runIpxtablesCmd(alertQuotaCmd, IptJumpNoAdd);
free(alertQuotaCmd);
return res;
}
int BandwidthController::setGlobalAlert(int64_t bytes) {
const char *alertName = ALERT_GLOBAL_NAME;
int res = 0;
if (!bytes) {
ALOGE("Invalid bytes value. 1..max_int64.");
return -1;
}
if (globalAlertBytes) {
res = updateQuota(alertName, bytes);
} else {
res = runIptablesAlertCmd(IptOpInsert, alertName, bytes);
if (globalAlertTetherCount) {
ALOGV("setGlobalAlert for %d tether", globalAlertTetherCount);
res |= runIptablesAlertFwdCmd(IptOpInsert, alertName, bytes);
}
}
globalAlertBytes = bytes;
return res;
}
int BandwidthController::setGlobalAlertInForwardChain(void) {
const char *alertName = ALERT_GLOBAL_NAME;
int res = 0;
globalAlertTetherCount++;
ALOGV("setGlobalAlertInForwardChain(): %d tether", globalAlertTetherCount);
/*
* If there is no globalAlert active we are done.
* If there is an active globalAlert but this is not the 1st
* tether, we are also done.
*/
if (!globalAlertBytes || globalAlertTetherCount != 1) {
return 0;
}
/* We only add the rule if this was the 1st tether added. */
res = runIptablesAlertFwdCmd(IptOpInsert, alertName, globalAlertBytes);
return res;
}
int BandwidthController::removeGlobalAlert(void) {
const char *alertName = ALERT_GLOBAL_NAME;
int res = 0;
if (!globalAlertBytes) {
ALOGE("No prior alert set");
return -1;
}
res = runIptablesAlertCmd(IptOpDelete, alertName, globalAlertBytes);
if (globalAlertTetherCount) {
res |= runIptablesAlertFwdCmd(IptOpDelete, alertName, globalAlertBytes);
}
globalAlertBytes = 0;
return res;
}
int BandwidthController::removeGlobalAlertInForwardChain(void) {
int res = 0;
const char *alertName = ALERT_GLOBAL_NAME;
if (!globalAlertTetherCount) {
ALOGE("No prior alert set");
return -1;
}
globalAlertTetherCount--;
/*
* If there is no globalAlert active we are done.
* If there is an active globalAlert but there are more
* tethers, we are also done.
*/
if (!globalAlertBytes || globalAlertTetherCount >= 1) {
return 0;
}
/* We only detete the rule if this was the last tether removed. */
res = runIptablesAlertFwdCmd(IptOpDelete, alertName, globalAlertBytes);
return res;
}
int BandwidthController::setSharedAlert(int64_t bytes) {
if (!sharedQuotaBytes) {
ALOGE("Need to have a prior shared quota set to set an alert");
return -1;
}
if (!bytes) {
ALOGE("Invalid bytes value. 1..max_int64.");
return -1;
}
return setCostlyAlert("shared", bytes, &sharedAlertBytes);
}
int BandwidthController::removeSharedAlert(void) {
return removeCostlyAlert("shared", &sharedAlertBytes);
}
int BandwidthController::setInterfaceAlert(const char *iface, int64_t bytes) {
std::list<QuotaInfo>::iterator it;
if (!isIfaceName(iface)) {
ALOGE("setInterfaceAlert: Invalid iface \"%s\"", iface);
return -1;
}
if (!bytes) {
ALOGE("Invalid bytes value. 1..max_int64.");
return -1;
}
for (it = quotaIfaces.begin(); it != quotaIfaces.end(); it++) {
if (it->ifaceName == iface)
break;
}
if (it == quotaIfaces.end()) {
ALOGE("Need to have a prior interface quota set to set an alert");
return -1;
}
return setCostlyAlert(iface, bytes, &it->alert);
}
int BandwidthController::removeInterfaceAlert(const char *iface) {
std::list<QuotaInfo>::iterator it;
if (!isIfaceName(iface)) {
ALOGE("removeInterfaceAlert: Invalid iface \"%s\"", iface);
return -1;
}
for (it = quotaIfaces.begin(); it != quotaIfaces.end(); it++) {
if (it->ifaceName == iface)
break;
}
if (it == quotaIfaces.end()) {
ALOGE("No prior alert set for interface %s", iface);
return -1;
}
return removeCostlyAlert(iface, &it->alert);
}
int BandwidthController::setCostlyAlert(const char *costName, int64_t bytes, int64_t *alertBytes) {
char *alertQuotaCmd;
char *chainName;
int res = 0;
char *alertName;
if (!isIfaceName(costName)) {
ALOGE("setCostlyAlert: Invalid costName \"%s\"", costName);
return -1;
}
if (!bytes) {
ALOGE("Invalid bytes value. 1..max_int64.");
return -1;
}
asprintf(&alertName, "%sAlert", costName);
if (*alertBytes) {
res = updateQuota(alertName, *alertBytes);
} else {
asprintf(&chainName, "bw_costly_%s", costName);
asprintf(&alertQuotaCmd, ALERT_IPT_TEMPLATE, "-A", chainName, bytes, alertName);
res |= runIpxtablesCmd(alertQuotaCmd, IptJumpNoAdd);
free(alertQuotaCmd);
free(chainName);
}
*alertBytes = bytes;
free(alertName);
return res;
}
int BandwidthController::removeCostlyAlert(const char *costName, int64_t *alertBytes) {
char *alertQuotaCmd;
char *chainName;
char *alertName;
int res = 0;
if (!isIfaceName(costName)) {
ALOGE("removeCostlyAlert: Invalid costName \"%s\"", costName);
return -1;
}
if (!*alertBytes) {
ALOGE("No prior alert set for %s alert", costName);
return -1;
}
asprintf(&alertName, "%sAlert", costName);
asprintf(&chainName, "bw_costly_%s", costName);
asprintf(&alertQuotaCmd, ALERT_IPT_TEMPLATE, "-D", chainName, *alertBytes, alertName);
res |= runIpxtablesCmd(alertQuotaCmd, IptJumpNoAdd);
free(alertQuotaCmd);
free(chainName);
*alertBytes = 0;
free(alertName);
return res;
}
void BandwidthController::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 natctrl_tether_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 natctrl_tether_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
*
* It results in an error if invoked and no tethering counter rules exist. The constraint
* helps detect complete parsing failure.
*/
int BandwidthController::addForwardChainStats(const TetherStats& filter,
TetherStatsList& statsList, FILE *fp,
std::string &extraProcessingInfo) {
int res;
char lineBuffer[MAX_IPT_OUTPUT_LINE_LEN];
char iface0[MAX_IPT_OUTPUT_LINE_LEN];
char iface1[MAX_IPT_OUTPUT_LINE_LEN];
char rest[MAX_IPT_OUTPUT_LINE_LEN];
TetherStats stats;
char *buffPtr;
int64_t packets, bytes;
int statsFound = 0;
bool filterPair = filter.intIface[0] && filter.extIface[0];
char *filterMsg = filter.getStatsLine();
ALOGV("filter: %s", filterMsg);
free(filterMsg);
stats = filter;
while (NULL != (buffPtr = fgets(lineBuffer, MAX_IPT_OUTPUT_LINE_LEN, fp))) {
/* 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;
if (res != 5) {
continue;
}
/*
* The following assumes that the 1st rule has in:extIface out:intIface,
* which is what NatController sets up.
* If not filtering, the 1st match rx, and sets up the pair for the tx side.
*/
if (filter.intIface[0] && filter.extIface[0]) {
if (filter.intIface == iface0 && filter.extIface == iface1) {
ALOGV("2Filter RX iface_in=%s iface_out=%s rx_bytes=%" PRId64" rx_packets=%" PRId64" ", iface0, iface1, bytes, packets);
stats.rxPackets = packets;
stats.rxBytes = bytes;
} else if (filter.intIface == iface1 && filter.extIface == iface0) {
ALOGV("2Filter TX iface_in=%s iface_out=%s rx_bytes=%" PRId64" rx_packets=%" PRId64" ", iface0, iface1, bytes, packets);
stats.txPackets = packets;
stats.txBytes = bytes;
}
} else if (filter.intIface[0] || filter.extIface[0]) {
if (filter.intIface == iface0 || filter.extIface == iface1) {
ALOGV("1Filter RX iface_in=%s iface_out=%s rx_bytes=%" PRId64" rx_packets=%" PRId64" ", iface0, iface1, bytes, packets);
stats.intIface = iface0;
stats.extIface = iface1;
stats.rxPackets = packets;
stats.rxBytes = bytes;
} else if (filter.intIface == iface1 || filter.extIface == iface0) {
ALOGV("1Filter TX iface_in=%s iface_out=%s rx_bytes=%" PRId64" rx_packets=%" PRId64" ", iface0, iface1, bytes, packets);
stats.intIface = iface1;
stats.extIface = iface0;
stats.txPackets = packets;
stats.txBytes = bytes;
}
} else /* if (!filter.intFace[0] && !filter.extIface[0]) */ {
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.rxPackets = packets;
stats.rxBytes = 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.txPackets = packets;
stats.txBytes = bytes;
}
}
if (stats.rxBytes != -1 && stats.txBytes != -1) {
ALOGV("rx_bytes=%" PRId64" tx_bytes=%" PRId64" filterPair=%d", stats.rxBytes, stats.txBytes, filterPair);
addStats(statsList, stats);
if (filterPair) {
return 0;
} else {
statsFound++;
stats = filter;
}
}
}
/* It is always an error to find only one side of the stats. */
/* It is an error to find nothing when not filtering. */
if (((stats.rxBytes == -1) != (stats.txBytes == -1)) ||
(!statsFound && !filterPair)) {
return -1;
}
return 0;
}
char *BandwidthController::TetherStats::getStatsLine(void) const {
char *msg;
asprintf(&msg, "%s %s %" PRId64" %" PRId64" %" PRId64" %" PRId64, intIface.c_str(), extIface.c_str(),
rxBytes, rxPackets, txBytes, txPackets);
return msg;
}
std::string getTetherStatsCommand(const char *binary) {
/*
* Why not use some kind of lib to talk to iptables?
* Because the only libs are libiptc and libip6tc in iptables, and they are
* not easy to use. They require the known iptables match modules to be
* preloaded/linked, and require apparently a lot of wrapper code to get
* the wanted info.
*/
return android::base::StringPrintf("%s -nvx -w -L %s", binary,
NatController::LOCAL_TETHER_COUNTERS_CHAIN);
}
int BandwidthController::getTetherStats(SocketClient *cli, TetherStats& filter,
std::string &extraProcessingInfo) {
int res = 0;
std::string fullCmd;
FILE *iptOutput;
TetherStatsList statsList;
for (const auto binary : {IPTABLES_PATH, IP6TABLES_PATH}) {
fullCmd = getTetherStatsCommand(binary);
iptOutput = popenFunction(fullCmd.c_str(), "r");
if (!iptOutput) {
ALOGE("Failed to run %s err=%s", fullCmd.c_str(), strerror(errno));
extraProcessingInfo += "Failed to run iptables.";
return -1;
}
res = addForwardChainStats(filter, statsList, iptOutput, extraProcessingInfo);
pclose(iptOutput);
if (res != 0) {
return res;
}
}
if (filter.intIface[0] && filter.extIface[0] && statsList.size() == 1) {
cli->sendMsg(ResponseCode::TetheringStatsResult, statsList[0].getStatsLine(), false);
} else {
for (const auto& stats: statsList) {
cli->sendMsg(ResponseCode::TetheringStatsListResult, stats.getStatsLine(), false);
}
if (res == 0) {
cli->sendMsg(ResponseCode::CommandOkay, "Tethering stats list completed", false);
}
}
return res;
}
void BandwidthController::flushExistingCostlyTables(bool doClean) {
std::string fullCmd;
FILE *iptOutput;
/* Only lookup ip4 table names as ip6 will have the same tables ... */
fullCmd = IPTABLES_PATH;
fullCmd += " -w -S";
iptOutput = popenFunction(fullCmd.c_str(), "r");
if (!iptOutput) {
ALOGE("Failed to run %s err=%s", fullCmd.c_str(), strerror(errno));
return;
}
/* ... then flush/clean both ip4 and ip6 iptables. */
parseAndFlushCostlyTables(iptOutput, doClean);
pclose(iptOutput);
}
void BandwidthController::parseAndFlushCostlyTables(FILE *fp, bool doRemove) {
int res;
char lineBuffer[MAX_IPT_OUTPUT_LINE_LEN];
char costlyIfaceName[MAX_IPT_OUTPUT_LINE_LEN];
char cmd[MAX_CMD_LEN];
char *buffPtr;
while (NULL != (buffPtr = fgets(lineBuffer, MAX_IPT_OUTPUT_LINE_LEN, fp))) {
costlyIfaceName[0] = '\0'; /* So that debugging output always works */
res = sscanf(buffPtr, "-N bw_costly_%s", costlyIfaceName);
ALOGV("parse res=%d costly=<%s> orig line=<%s>", res,
costlyIfaceName, buffPtr);
if (res != 1) {
continue;
}
/* Exclusions: "shared" is not an ifacename */
if (!strcmp(costlyIfaceName, "shared")) {
continue;
}
snprintf(cmd, sizeof(cmd), "-F bw_costly_%s", costlyIfaceName);
runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
if (doRemove) {
snprintf(cmd, sizeof(cmd), "-X bw_costly_%s", costlyIfaceName);
runIpxtablesCmd(cmd, IptJumpNoAdd, IptFailHide);
}
}
}