Source code
Revision control
Copy as Markdown
Other Tools
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set et sw=2 ts=4: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include <arpa/inet.h>
#include <netinet/ether.h>
#include <net/if.h>
#include <poll.h>
#include <unistd.h>
#include <linux/rtnetlink.h>
#include <ifaddrs.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "nsThreadUtils.h"
#include "NetlinkService.h"
#include "nsIThread.h"
#include "nsString.h"
#include "nsPrintfCString.h"
#include "mozilla/Logging.h"
#include "../../base/IPv6Utils.h"
#include "../LinkServiceCommon.h"
#include "../NetworkLinkServiceDefines.h"
#include "mozilla/Base64.h"
#include "mozilla/FunctionTypeTraits.h"
#include "mozilla/ProfilerThreadSleep.h"
#include "mozilla/Telemetry.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/ScopeExit.h"
#if defined(HAVE_RES_NINIT)
# include <netinet/in.h>
# include <resolv.h>
#endif
namespace mozilla::net {
template <typename F>
static auto eintr_retry(F&& func) ->
typename FunctionTypeTraits<decltype(func)>::ReturnType {
typename FunctionTypeTraits<decltype(func)>::ReturnType _rc;
do {
_rc = func();
} while (_rc == -1 && errno == EINTR);
return _rc;
}
#define EINTR_RETRY(expr) eintr_retry([&]() { return expr; })
// period during which to absorb subsequent network change events, in
// milliseconds
static const unsigned int kNetworkChangeCoalescingPeriod = 1000;
static LazyLogModule gNlSvcLog("NetlinkService");
#define LOG(args) MOZ_LOG(gNlSvcLog, mozilla::LogLevel::Debug, args)
#undef LOG_ENABLED
#define LOG_ENABLED() MOZ_LOG_TEST(gNlSvcLog, mozilla::LogLevel::Debug)
using in_common_addr = union {
struct in_addr addr4;
struct in6_addr addr6;
};
static void GetAddrStr(const in_common_addr* aAddr, uint8_t aFamily,
nsACString& _retval) {
char addr[INET6_ADDRSTRLEN];
addr[0] = 0;
if (aFamily == AF_INET) {
inet_ntop(AF_INET, &(aAddr->addr4), addr, INET_ADDRSTRLEN);
} else {
inet_ntop(AF_INET6, &(aAddr->addr6), addr, INET6_ADDRSTRLEN);
}
_retval.Assign(addr);
}
// Assume true by default.
static Atomic<bool, MemoryOrdering::Relaxed> sHasNonLocalIPv6{true};
// static
bool NetlinkService::HasNonLocalIPv6Address() { return sHasNonLocalIPv6; }
class NetlinkAddress {
public:
NetlinkAddress() = default;
uint8_t Family() const { return mIfam.ifa_family; }
uint32_t GetIndex() const { return mIfam.ifa_index; }
uint8_t GetPrefixLen() const { return mIfam.ifa_prefixlen; }
bool ScopeIsUniverse() const { return mIfam.ifa_scope == RT_SCOPE_UNIVERSE; }
const in_common_addr* GetAddrPtr() const { return &mAddr; }
bool MsgEquals(const NetlinkAddress& aOther) const {
return !memcmp(&mIfam, &(aOther.mIfam), sizeof(mIfam));
}
bool Equals(const NetlinkAddress& aOther) const {
if (mIfam.ifa_family != aOther.mIfam.ifa_family) {
return false;
}
if (mIfam.ifa_index != aOther.mIfam.ifa_index) {
// addresses are different when they are on a different interface
return false;
}
if (mIfam.ifa_prefixlen != aOther.mIfam.ifa_prefixlen) {
// It's possible to have two equal addresses with a different netmask on
// the same interface, so we need to check prefixlen too.
return false;
}
size_t addrSize = (mIfam.ifa_family == AF_INET) ? sizeof(mAddr.addr4)
: sizeof(mAddr.addr6);
return memcmp(&mAddr, aOther.GetAddrPtr(), addrSize) == 0;
}
bool ContainsAddr(const in_common_addr* aAddr) {
int32_t addrSize = (mIfam.ifa_family == AF_INET)
? (int32_t)sizeof(mAddr.addr4)
: (int32_t)sizeof(mAddr.addr6);
uint8_t maskit[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe};
int32_t bits = mIfam.ifa_prefixlen;
if (bits > addrSize * 8) {
MOZ_ASSERT(false, "Unexpected prefix length!");
LOG(("Unexpected prefix length %d, maximum for this family is %d", bits,
addrSize * 8));
return false;
}
for (int32_t i = 0; i < addrSize; i++) {
uint8_t mask = (bits >= 8) ? 0xff : maskit[bits];
if ((((unsigned char*)aAddr)[i] & mask) !=
(((unsigned char*)(&mAddr))[i] & mask)) {
return false;
}
bits -= 8;
if (bits <= 0) {
return true;
}
}
return true;
}
bool Init(struct nlmsghdr* aNlh) {
struct ifaddrmsg* ifam;
struct rtattr* attr;
int len;
ifam = (ifaddrmsg*)NLMSG_DATA(aNlh);
len = IFA_PAYLOAD(aNlh);
if (ifam->ifa_family != AF_INET && ifam->ifa_family != AF_INET6) {
return false;
}
bool hasAddr = false;
for (attr = IFA_RTA(ifam); RTA_OK(attr, len); attr = RTA_NEXT(attr, len)) {
if (attr->rta_type == IFA_ADDRESS || attr->rta_type == IFA_LOCAL) {
memcpy(&mAddr, RTA_DATA(attr),
ifam->ifa_family == AF_INET ? sizeof(mAddr.addr4)
: sizeof(mAddr.addr6));
hasAddr = true;
if (attr->rta_type == IFA_LOCAL) {
// local address is preferred, so don't continue parsing other
// attributes
break;
}
}
}
if (!hasAddr) {
return false;
}
memcpy(&mIfam, (ifaddrmsg*)NLMSG_DATA(aNlh), sizeof(mIfam));
return true;
}
private:
in_common_addr mAddr;
struct ifaddrmsg mIfam;
};
class NetlinkNeighbor {
public:
NetlinkNeighbor() = default;
uint8_t Family() const { return mNeigh.ndm_family; }
uint32_t GetIndex() const { return mNeigh.ndm_ifindex; }
const in_common_addr* GetAddrPtr() const { return &mAddr; }
const uint8_t* GetMACPtr() const { return mMAC; }
bool HasMAC() const { return mHasMAC; }
void GetAsString(nsACString& _retval) const {
nsAutoCString addrStr;
_retval.Assign("addr=");
GetAddrStr(&mAddr, mNeigh.ndm_family, addrStr);
_retval.Append(addrStr);
if (mNeigh.ndm_family == AF_INET) {
_retval.Append(" family=AF_INET if=");
} else {
_retval.Append(" family=AF_INET6 if=");
}
_retval.AppendInt(mNeigh.ndm_ifindex);
if (mHasMAC) {
_retval.Append(" mac=");
_retval.Append(nsPrintfCString("%02x:%02x:%02x:%02x:%02x:%02x", mMAC[0],
mMAC[1], mMAC[2], mMAC[3], mMAC[4],
mMAC[5]));
}
}
bool Init(struct nlmsghdr* aNlh) {
struct ndmsg* neigh;
struct rtattr* attr;
int len;
neigh = (ndmsg*)NLMSG_DATA(aNlh);
len = aNlh->nlmsg_len - NLMSG_LENGTH(sizeof(*neigh));
if (neigh->ndm_family != AF_INET && neigh->ndm_family != AF_INET6) {
return false;
}
bool hasDST = false;
for (attr = RTM_RTA(neigh); RTA_OK(attr, len); attr = RTA_NEXT(attr, len)) {
if (attr->rta_type == NDA_LLADDR) {
memcpy(mMAC, RTA_DATA(attr), ETH_ALEN);
mHasMAC = true;
}
if (attr->rta_type == NDA_DST) {
memcpy(&mAddr, RTA_DATA(attr),
neigh->ndm_family == AF_INET ? sizeof(mAddr.addr4)
: sizeof(mAddr.addr6));
hasDST = true;
}
}
if (!hasDST) {
return false;
}
memcpy(&mNeigh, (ndmsg*)NLMSG_DATA(aNlh), sizeof(mNeigh));
return true;
}
private:
bool mHasMAC{false};
uint8_t mMAC[ETH_ALEN]{};
in_common_addr mAddr{};
struct ndmsg mNeigh {};
};
class NetlinkLink {
public:
NetlinkLink() = default;
bool IsUp() const {
return (mIface.ifi_flags & IFF_RUNNING) &&
!(mIface.ifi_flags & IFF_LOOPBACK);
}
void GetName(nsACString& _retval) const { _retval = mName; }
bool IsTypeEther() const { return mIface.ifi_type == ARPHRD_ETHER; }
uint32_t GetIndex() const { return mIface.ifi_index; }
uint32_t GetFlags() const { return mIface.ifi_flags; }
uint16_t GetType() const { return mIface.ifi_type; }
bool Init(struct nlmsghdr* aNlh) {
struct ifinfomsg* iface;
struct rtattr* attr;
int len;
iface = (ifinfomsg*)NLMSG_DATA(aNlh);
len = aNlh->nlmsg_len - NLMSG_LENGTH(sizeof(*iface));
bool hasName = false;
for (attr = IFLA_RTA(iface); RTA_OK(attr, len);
attr = RTA_NEXT(attr, len)) {
if (attr->rta_type == IFLA_IFNAME) {
mName.Assign((char*)RTA_DATA(attr));
hasName = true;
break;
}
}
if (!hasName) {
return false;
}
memcpy(&mIface, (ifinfomsg*)NLMSG_DATA(aNlh), sizeof(mIface));
return true;
}
private:
nsCString mName;
struct ifinfomsg mIface {};
};
class NetlinkRoute {
public:
NetlinkRoute()
: mHasGWAddr(false),
mHasPrefSrcAddr(false),
mHasDstAddr(false),
mHasOif(false),
mHasPrio(false) {}
bool IsUnicast() const { return mRtm.rtm_type == RTN_UNICAST; }
bool ScopeIsUniverse() const { return mRtm.rtm_scope == RT_SCOPE_UNIVERSE; }
bool IsDefault() const { return mRtm.rtm_dst_len == 0; }
bool HasOif() const { return mHasOif; }
uint8_t Oif() const { return mOif; }
uint8_t Family() const { return mRtm.rtm_family; }
bool HasPrefSrcAddr() const { return mHasPrefSrcAddr; }
const in_common_addr* GetGWAddrPtr() const {
return mHasGWAddr ? &mGWAddr : nullptr;
}
const in_common_addr* GetPrefSrcAddrPtr() const {
return mHasPrefSrcAddr ? &mPrefSrcAddr : nullptr;
}
bool Equals(const NetlinkRoute& aOther) const {
size_t addrSize = (mRtm.rtm_family == AF_INET) ? sizeof(mDstAddr.addr4)
: sizeof(mDstAddr.addr6);
if (memcmp(&mRtm, &(aOther.mRtm), sizeof(mRtm)) != 0) {
return false;
}
if (mHasOif != aOther.mHasOif || mOif != aOther.mOif) {
return false;
}
if (mHasPrio != aOther.mHasPrio || mPrio != aOther.mPrio) {
return false;
}
if ((mHasGWAddr != aOther.mHasGWAddr) ||
(mHasGWAddr && memcmp(&mGWAddr, &(aOther.mGWAddr), addrSize) != 0)) {
return false;
}
if ((mHasDstAddr != aOther.mHasDstAddr) ||
(mHasDstAddr && memcmp(&mDstAddr, &(aOther.mDstAddr), addrSize) != 0)) {
return false;
}
if ((mHasPrefSrcAddr != aOther.mHasPrefSrcAddr) ||
(mHasPrefSrcAddr &&
memcmp(&mPrefSrcAddr, &(aOther.mPrefSrcAddr), addrSize) != 0)) {
return false;
}
return true;
}
bool GatewayEquals(const NetlinkNeighbor& aNeigh) const {
if (!mHasGWAddr) {
return false;
}
if (aNeigh.Family() != mRtm.rtm_family) {
return false;
}
size_t addrSize = (mRtm.rtm_family == AF_INET) ? sizeof(mGWAddr.addr4)
: sizeof(mGWAddr.addr6);
return memcmp(&mGWAddr, aNeigh.GetAddrPtr(), addrSize) == 0;
}
bool GatewayEquals(const NetlinkRoute* aRoute) const {
if (!mHasGWAddr || !aRoute->mHasGWAddr) {
return false;
}
if (mRtm.rtm_family != aRoute->mRtm.rtm_family) {
return false;
}
size_t addrSize = (mRtm.rtm_family == AF_INET) ? sizeof(mGWAddr.addr4)
: sizeof(mGWAddr.addr6);
return memcmp(&mGWAddr, &(aRoute->mGWAddr), addrSize) == 0;
}
bool PrefSrcAddrEquals(const NetlinkAddress& aAddress) const {
if (!mHasPrefSrcAddr) {
return false;
}
if (mRtm.rtm_family != aAddress.Family()) {
return false;
}
size_t addrSize = (mRtm.rtm_family == AF_INET) ? sizeof(mPrefSrcAddr.addr4)
: sizeof(mPrefSrcAddr.addr6);
return memcmp(&mPrefSrcAddr, aAddress.GetAddrPtr(), addrSize) == 0;
}
void GetAsString(nsACString& _retval) const {
nsAutoCString addrStr;
_retval.Assign("table=");
_retval.AppendInt(mRtm.rtm_table);
_retval.Append(" type=");
_retval.AppendInt(mRtm.rtm_type);
_retval.Append(" scope=");
_retval.AppendInt(mRtm.rtm_scope);
if (mRtm.rtm_family == AF_INET) {
_retval.Append(" family=AF_INET dst=");
addrStr.Assign("0.0.0.0/");
} else {
_retval.Append(" family=AF_INET6 dst=");
addrStr.Assign("::/");
}
if (mHasDstAddr) {
GetAddrStr(&mDstAddr, mRtm.rtm_family, addrStr);
addrStr.Append("/");
}
_retval.Append(addrStr);
_retval.AppendInt(mRtm.rtm_dst_len);
if (mHasPrefSrcAddr) {
_retval.Append(" src=");
GetAddrStr(&mPrefSrcAddr, mRtm.rtm_family, addrStr);
_retval.Append(addrStr);
}
if (mHasGWAddr) {
_retval.Append(" via=");
GetAddrStr(&mGWAddr, mRtm.rtm_family, addrStr);
_retval.Append(addrStr);
}
if (mHasOif) {
_retval.Append(" oif=");
_retval.AppendInt(mOif);
}
if (mHasPrio) {
_retval.Append(" prio=");
_retval.AppendInt(mPrio);
}
}
bool Init(struct nlmsghdr* aNlh) {
struct rtmsg* rtm;
struct rtattr* attr;
int len;
rtm = (rtmsg*)NLMSG_DATA(aNlh);
len = RTM_PAYLOAD(aNlh);
if (rtm->rtm_family != AF_INET && rtm->rtm_family != AF_INET6) {
return false;
}
for (attr = RTM_RTA(rtm); RTA_OK(attr, len); attr = RTA_NEXT(attr, len)) {
if (attr->rta_type == RTA_DST) {
memcpy(&mDstAddr, RTA_DATA(attr),
(rtm->rtm_family == AF_INET) ? sizeof(mDstAddr.addr4)
: sizeof(mDstAddr.addr6));
mHasDstAddr = true;
} else if (attr->rta_type == RTA_GATEWAY) {
memcpy(&mGWAddr, RTA_DATA(attr),
(rtm->rtm_family == AF_INET) ? sizeof(mGWAddr.addr4)
: sizeof(mGWAddr.addr6));
mHasGWAddr = true;
} else if (attr->rta_type == RTA_PREFSRC) {
memcpy(&mPrefSrcAddr, RTA_DATA(attr),
(rtm->rtm_family == AF_INET) ? sizeof(mPrefSrcAddr.addr4)
: sizeof(mPrefSrcAddr.addr6));
mHasPrefSrcAddr = true;
} else if (attr->rta_type == RTA_OIF) {
mOif = *(uint32_t*)RTA_DATA(attr);
mHasOif = true;
} else if (attr->rta_type == RTA_PRIORITY) {
mPrio = *(uint32_t*)RTA_DATA(attr);
mHasPrio = true;
}
}
memcpy(&mRtm, (rtmsg*)NLMSG_DATA(aNlh), sizeof(mRtm));
return true;
}
private:
bool mHasGWAddr : 1;
bool mHasPrefSrcAddr : 1;
bool mHasDstAddr : 1;
bool mHasOif : 1;
bool mHasPrio : 1;
in_common_addr mGWAddr{};
in_common_addr mDstAddr{};
in_common_addr mPrefSrcAddr{};
uint32_t mOif{};
uint32_t mPrio{};
struct rtmsg mRtm {};
};
class NetlinkMsg {
public:
static uint8_t const kGenMsg = 1;
static uint8_t const kRtMsg = 2;
NetlinkMsg() = default;
virtual ~NetlinkMsg() = default;
virtual bool Send(int aFD) = 0;
virtual bool IsPending() { return mIsPending; }
virtual uint32_t SeqId() = 0;
virtual uint8_t Family() = 0;
virtual uint8_t MsgType() = 0;
protected:
bool SendRequest(int aFD, void* aRequest, uint32_t aRequestLength) {
MOZ_ASSERT(!mIsPending, "Request has been already sent!");
struct sockaddr_nl kernel {};
memset(&kernel, 0, sizeof(kernel));
kernel.nl_family = AF_NETLINK;
kernel.nl_groups = 0;
struct iovec io {};
memset(&io, 0, sizeof(io));
io.iov_base = aRequest;
io.iov_len = aRequestLength;
struct msghdr rtnl_msg {};
memset(&rtnl_msg, 0, sizeof(rtnl_msg));
rtnl_msg.msg_iov = &io;
rtnl_msg.msg_iovlen = 1;
rtnl_msg.msg_name = &kernel;
rtnl_msg.msg_namelen = sizeof(kernel);
ssize_t rc = EINTR_RETRY(sendmsg(aFD, (struct msghdr*)&rtnl_msg, 0));
if (rc > 0 && (uint32_t)rc == aRequestLength) {
mIsPending = true;
}
return mIsPending;
}
bool mIsPending{false};
};
class NetlinkGenMsg : public NetlinkMsg {
public:
NetlinkGenMsg(uint16_t aMsgType, uint8_t aFamily, uint32_t aSeqId) {
memset(&mReq, 0, sizeof(mReq));
mReq.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtgenmsg));
mReq.hdr.nlmsg_type = aMsgType;
mReq.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
mReq.hdr.nlmsg_seq = aSeqId;
mReq.hdr.nlmsg_pid = 0;
mReq.gen.rtgen_family = aFamily;
}
virtual bool Send(int aFD) {
return SendRequest(aFD, &mReq, mReq.hdr.nlmsg_len);
}
virtual uint32_t SeqId() { return mReq.hdr.nlmsg_seq; }
virtual uint8_t Family() { return mReq.gen.rtgen_family; }
virtual uint8_t MsgType() { return kGenMsg; }
private:
struct {
struct nlmsghdr hdr;
struct rtgenmsg gen;
} mReq{};
};
class NetlinkRtMsg : public NetlinkMsg {
public:
NetlinkRtMsg(uint8_t aFamily, void* aAddress, uint32_t aSeqId) {
MOZ_ASSERT(aFamily == AF_INET || aFamily == AF_INET6);
memset(&mReq, 0, sizeof(mReq));
mReq.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
mReq.hdr.nlmsg_type = RTM_GETROUTE;
mReq.hdr.nlmsg_flags = NLM_F_REQUEST;
mReq.hdr.nlmsg_seq = aSeqId;
mReq.hdr.nlmsg_pid = 0;
mReq.rtm.rtm_family = aFamily;
mReq.rtm.rtm_flags = 0;
mReq.rtm.rtm_dst_len = aFamily == AF_INET ? 32 : 128;
struct rtattr* rta;
rta = (struct rtattr*)(((char*)&mReq) + NLMSG_ALIGN(mReq.hdr.nlmsg_len));
rta->rta_type = RTA_DST;
size_t addrSize =
aFamily == AF_INET ? sizeof(struct in_addr) : sizeof(struct in6_addr);
rta->rta_len = RTA_LENGTH(addrSize);
memcpy(RTA_DATA(rta), aAddress, addrSize);
mReq.hdr.nlmsg_len = NLMSG_ALIGN(mReq.hdr.nlmsg_len) + RTA_LENGTH(addrSize);
}
virtual bool Send(int aFD) {
return SendRequest(aFD, &mReq, mReq.hdr.nlmsg_len);
}
virtual uint32_t SeqId() { return mReq.hdr.nlmsg_seq; }
virtual uint8_t Family() { return mReq.rtm.rtm_family; }
virtual uint8_t MsgType() { return kRtMsg; }
private:
struct {
struct nlmsghdr hdr;
struct rtmsg rtm;
unsigned char data[1024];
} mReq{};
};
NetlinkService::LinkInfo::LinkInfo(UniquePtr<NetlinkLink>&& aLink)
: mLink(std::move(aLink)), mIsUp(false) {}
NetlinkService::LinkInfo::~LinkInfo() = default;
bool NetlinkService::LinkInfo::UpdateStatus() {
LOG(("NetlinkService::LinkInfo::UpdateStatus"));
bool oldIsUp = mIsUp;
mIsUp = false;
if (!mLink->IsUp()) {
// The link is not up or is a loopback
LOG(("The link is down or is a loopback"));
} else {
// Link is up when there is non-local address associated with it.
for (uint32_t i = 0; i < mAddresses.Length(); ++i) {
if (LOG_ENABLED()) {
nsAutoCString dbgStr;
GetAddrStr(mAddresses[i]->GetAddrPtr(), mAddresses[i]->Family(),
dbgStr);
LOG(("checking address %s", dbgStr.get()));
}
if (mAddresses[i]->ScopeIsUniverse()) {
mIsUp = true;
LOG(("global address found"));
break;
}
}
}
return mIsUp == oldIsUp;
}
NS_IMPL_ISUPPORTS(NetlinkService, nsIRunnable)
NetlinkService::NetlinkService() : mPid(getpid()) {}
NetlinkService::~NetlinkService() {
MOZ_ASSERT(!mThread, "NetlinkService thread shutdown failed");
if (mShutdownPipe[0] != -1) {
EINTR_RETRY(close(mShutdownPipe[0]));
}
if (mShutdownPipe[1] != -1) {
EINTR_RETRY(close(mShutdownPipe[1]));
}
}
void NetlinkService::OnNetlinkMessage(int aNetlinkSocket) {
// The buffer size 4096 is a common page size, which is a recommended limit
// for netlink messages.
char buffer[4096];
struct sockaddr_nl kernel {};
memset(&kernel, 0, sizeof(kernel));
kernel.nl_family = AF_NETLINK;
kernel.nl_groups = 0;
struct iovec io {};
memset(&io, 0, sizeof(io));
io.iov_base = buffer;
io.iov_len = sizeof(buffer);
struct msghdr rtnl_reply {};
memset(&rtnl_reply, 0, sizeof(rtnl_reply));
rtnl_reply.msg_iov = &io;
rtnl_reply.msg_iovlen = 1;
rtnl_reply.msg_name = &kernel;
rtnl_reply.msg_namelen = sizeof(kernel);
ssize_t rc = EINTR_RETRY(recvmsg(aNetlinkSocket, &rtnl_reply, MSG_DONTWAIT));
if (rc < 0) {
return;
}
size_t netlink_bytes = rc;
struct nlmsghdr* nlh = reinterpret_cast<struct nlmsghdr*>(buffer);
for (; NLMSG_OK(nlh, netlink_bytes); nlh = NLMSG_NEXT(nlh, netlink_bytes)) {
// If PID in the message is our PID, then it's a response to our request.
// Otherwise it's a multicast message.
bool isResponse = (pid_t)nlh->nlmsg_pid == mPid;
if (isResponse) {
if (!mOutgoingMessages.Length() || !mOutgoingMessages[0]->IsPending()) {
// There is no enqueued message pending?
LOG((
"Ignoring message seq_id %u, because there is no associated message"
" pending",
nlh->nlmsg_seq));
continue;
}
if (mOutgoingMessages[0]->SeqId() != nlh->nlmsg_seq) {
LOG(("Received unexpected seq_id [received=%u, expected=%u]",
nlh->nlmsg_seq, mOutgoingMessages[0]->SeqId()));
RemovePendingMsg();
continue;
}
}
switch (nlh->nlmsg_type) {
case NLMSG_DONE: /* Message signalling end of dump for responses to
request containing NLM_F_DUMP flag */
LOG(("received NLMSG_DONE"));
if (isResponse) {
RemovePendingMsg();
}
break;
case NLMSG_ERROR:
LOG(("received NLMSG_ERROR"));
if (isResponse) {
if (mOutgoingMessages[0]->MsgType() == NetlinkMsg::kRtMsg) {
OnRouteCheckResult(nullptr);
}
RemovePendingMsg();
}
break;
case RTM_NEWLINK:
case RTM_DELLINK:
MOZ_ASSERT(!isResponse ||
(nlh->nlmsg_flags & NLM_F_MULTI) == NLM_F_MULTI);
OnLinkMessage(nlh);
break;
case RTM_NEWADDR:
case RTM_DELADDR:
MOZ_ASSERT(!isResponse ||
(nlh->nlmsg_flags & NLM_F_MULTI) == NLM_F_MULTI);
OnAddrMessage(nlh);
break;
case RTM_NEWROUTE:
case RTM_DELROUTE:
if (isResponse && ((nlh->nlmsg_flags & NLM_F_MULTI) != NLM_F_MULTI)) {
// If it's not multipart message, then it must be response to a route
// check.
MOZ_ASSERT(mOutgoingMessages[0]->MsgType() == NetlinkMsg::kRtMsg);
OnRouteCheckResult(nlh);
RemovePendingMsg();
} else {
OnRouteMessage(nlh);
}
break;
case RTM_NEWNEIGH:
case RTM_DELNEIGH:
MOZ_ASSERT(!isResponse ||
(nlh->nlmsg_flags & NLM_F_MULTI) == NLM_F_MULTI);
OnNeighborMessage(nlh);
break;
default:
break;
}
}
}
void NetlinkService::OnLinkMessage(struct nlmsghdr* aNlh) {
LOG(("NetlinkService::OnLinkMessage [type=%s]",
aNlh->nlmsg_type == RTM_NEWLINK ? "new" : "del"));
UniquePtr<NetlinkLink> link(new NetlinkLink());
if (!link->Init(aNlh)) {
return;
}
const uint32_t linkIndex = link->GetIndex();
mLinks.WithEntryHandle(linkIndex, [&](auto&& entry) {
nsAutoCString linkName;
link->GetName(linkName);
if (aNlh->nlmsg_type == RTM_NEWLINK) {
if (!entry) {
LOG(("Creating new link [index=%u, name=%s, flags=%u, type=%u]",
linkIndex, linkName.get(), link->GetFlags(), link->GetType()));
entry.Insert(MakeUnique<LinkInfo>(std::move(link)));
} else {
LOG(("Updating link [index=%u, name=%s, flags=%u, type=%u]", linkIndex,
linkName.get(), link->GetFlags(), link->GetType()));
auto* linkInfo = entry->get();
// Check whether administrative state has changed.
if (linkInfo->mLink->GetFlags() & IFF_UP &&
!(link->GetFlags() & IFF_UP)) {
LOG((" link went down"));
// If the link went down, remove all routes and neighbors, but keep
// addresses.
linkInfo->mDefaultRoutes.Clear();
linkInfo->mNeighbors.Clear();
}
linkInfo->mLink = std::move(link);
linkInfo->UpdateStatus();
}
} else {
if (!entry) {
// This can happen during startup
LOG(("Link info doesn't exist [index=%u, name=%s]", linkIndex,
linkName.get()));
} else {
LOG(("Removing link [index=%u, name=%s]", linkIndex, linkName.get()));
entry.Remove();
}
}
});
}
void NetlinkService::OnAddrMessage(struct nlmsghdr* aNlh) {
LOG(("NetlinkService::OnAddrMessage [type=%s]",
aNlh->nlmsg_type == RTM_NEWADDR ? "new" : "del"));
UniquePtr<NetlinkAddress> address(new NetlinkAddress());
if (!address->Init(aNlh)) {
return;
}
uint32_t ifIdx = address->GetIndex();
nsAutoCString addrStr;
GetAddrStr(address->GetAddrPtr(), address->Family(), addrStr);
LinkInfo* linkInfo = nullptr;
mLinks.Get(ifIdx, &linkInfo);
if (!linkInfo) {
// This can happen during startup
LOG(("Cannot find link info [ifIdx=%u, addr=%s/%u", ifIdx, addrStr.get(),
address->GetPrefixLen()));
return;
}
// There might be already an equal address in the array even in case of
// RTM_NEWADDR message, e.g. when lifetime of IPv6 address is renewed. Equal
// in this case means that IP and prefix is the same but some attributes
// might be different. Remove existing equal address in case of RTM_DELADDR
// as well as RTM_NEWADDR message and add a new one in the latter case.
for (uint32_t i = 0; i < linkInfo->mAddresses.Length(); ++i) {
if (aNlh->nlmsg_type == RTM_NEWADDR &&
linkInfo->mAddresses[i]->MsgEquals(*address)) {
// If the new address is exactly the same, there is nothing to do.
LOG(("Exactly the same address already exists [ifIdx=%u, addr=%s/%u",
ifIdx, addrStr.get(), address->GetPrefixLen()));
return;
}
if (linkInfo->mAddresses[i]->Equals(*address)) {
LOG(("Removing address [ifIdx=%u, addr=%s/%u]", ifIdx, addrStr.get(),
address->GetPrefixLen()));
linkInfo->mAddresses.RemoveElementAt(i);
break;
}
}
if (aNlh->nlmsg_type == RTM_NEWADDR) {
LOG(("Adding address [ifIdx=%u, addr=%s/%u]", ifIdx, addrStr.get(),
address->GetPrefixLen()));
linkInfo->mAddresses.AppendElement(std::move(address));
} else {
// Remove all routes associated with this address
for (uint32_t i = linkInfo->mDefaultRoutes.Length(); i-- > 0;) {
MOZ_ASSERT(linkInfo->mDefaultRoutes[i]->GetGWAddrPtr(),
"Stored routes must have gateway!");
if (linkInfo->mDefaultRoutes[i]->Family() == address->Family() &&
address->ContainsAddr(linkInfo->mDefaultRoutes[i]->GetGWAddrPtr())) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
linkInfo->mDefaultRoutes[i]->GetAsString(routeDbgStr);
LOG(("Removing default route: %s", routeDbgStr.get()));
}
linkInfo->mDefaultRoutes.RemoveElementAt(i);
}
}
// Remove all neighbors associated with this address
for (auto iter = linkInfo->mNeighbors.Iter(); !iter.Done(); iter.Next()) {
NetlinkNeighbor* neigh = iter.UserData();
if (neigh->Family() == address->Family() &&
address->ContainsAddr(neigh->GetAddrPtr())) {
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
neigh->GetAsString(neighDbgStr);
LOG(("Removing neighbor %s", neighDbgStr.get()));
}
iter.Remove();
}
}
}
// Address change on the interface can change its status
linkInfo->UpdateStatus();
// Don't treat address changes during initial scan as a network change
if (mInitialScanFinished) {
// Send network event change regardless of whether the ID has changed or
// not
mSendNetworkChangeEvent = true;
TriggerNetworkIDCalculation();
}
}
void NetlinkService::OnRouteMessage(struct nlmsghdr* aNlh) {
LOG(("NetlinkService::OnRouteMessage [type=%s]",
aNlh->nlmsg_type == RTM_NEWROUTE ? "new" : "del"));
UniquePtr<NetlinkRoute> route(new NetlinkRoute());
if (!route->Init(aNlh)) {
return;
}
if (!route->IsUnicast() || !route->ScopeIsUniverse()) {
// Use only unicast routes
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Not an unicast global route: %s", routeDbgStr.get()));
}
return;
}
// Adding/removing any unicast route might change network ID
TriggerNetworkIDCalculation();
if (!route->IsDefault()) {
// Store only default routes
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Not a default route: %s", routeDbgStr.get()));
}
return;
}
if (!route->HasOif()) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("There is no output interface in route: %s", routeDbgStr.get()));
}
return;
}
if (!route->GetGWAddrPtr()) {
// We won't use the route if there is no gateway, so don't store it
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("There is no gateway in route: %s", routeDbgStr.get()));
}
return;
}
if (route->Family() == AF_INET6 &&
net::utils::ipv6_scope((const unsigned char*)route->GetGWAddrPtr()) !=
IPV6_SCOPE_GLOBAL) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Scope of GW isn't global: %s", routeDbgStr.get()));
}
return;
}
LinkInfo* linkInfo = nullptr;
mLinks.Get(route->Oif(), &linkInfo);
if (!linkInfo) {
// This can happen during startup
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Cannot find link info for route: %s", routeDbgStr.get()));
}
return;
}
for (uint32_t i = 0; i < linkInfo->mDefaultRoutes.Length(); ++i) {
if (linkInfo->mDefaultRoutes[i]->Equals(*route)) {
// We shouldn't find equal route when adding a new one, but just in case
// it can happen remove the old one to avoid duplicities.
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Removing default route: %s", routeDbgStr.get()));
}
linkInfo->mDefaultRoutes.RemoveElementAt(i);
break;
}
}
if (aNlh->nlmsg_type == RTM_NEWROUTE) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Adding default route: %s", routeDbgStr.get()));
}
linkInfo->mDefaultRoutes.AppendElement(std::move(route));
}
}
void NetlinkService::OnNeighborMessage(struct nlmsghdr* aNlh) {
LOG(("NetlinkService::OnNeighborMessage [type=%s]",
aNlh->nlmsg_type == RTM_NEWNEIGH ? "new" : "del"));
UniquePtr<NetlinkNeighbor> neigh(new NetlinkNeighbor());
if (!neigh->Init(aNlh)) {
return;
}
LinkInfo* linkInfo = nullptr;
mLinks.Get(neigh->GetIndex(), &linkInfo);
if (!linkInfo) {
// This can happen during startup
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
neigh->GetAsString(neighDbgStr);
LOG(("Cannot find link info for neighbor: %s", neighDbgStr.get()));
}
return;
}
if (!linkInfo->mLink->IsTypeEther()) {
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
neigh->GetAsString(neighDbgStr);
LOG(("Ignoring message on non-ethernet link: %s", neighDbgStr.get()));
}
return;
}
nsAutoCString key;
GetAddrStr(neigh->GetAddrPtr(), neigh->Family(), key);
if (aNlh->nlmsg_type == RTM_NEWNEIGH) {
if (!mRecalculateNetworkId && neigh->HasMAC()) {
NetlinkNeighbor* oldNeigh = nullptr;
linkInfo->mNeighbors.Get(key, &oldNeigh);
if (!oldNeigh || !oldNeigh->HasMAC()) {
// The MAC address was added, if it's a host from some of the saved
// routing tables we should recalculate network ID
for (uint32_t i = 0; i < linkInfo->mDefaultRoutes.Length(); ++i) {
if (linkInfo->mDefaultRoutes[i]->GatewayEquals(*neigh)) {
TriggerNetworkIDCalculation();
break;
}
}
if ((mIPv4RouteCheckResult &&
mIPv4RouteCheckResult->GatewayEquals(*neigh)) ||
(mIPv6RouteCheckResult &&
mIPv6RouteCheckResult->GatewayEquals(*neigh))) {
TriggerNetworkIDCalculation();
}
}
}
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
neigh->GetAsString(neighDbgStr);
LOG(("Adding neighbor: %s", neighDbgStr.get()));
}
linkInfo->mNeighbors.InsertOrUpdate(key, std::move(neigh));
} else {
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
neigh->GetAsString(neighDbgStr);
LOG(("Removing neighbor %s", neighDbgStr.get()));
}
linkInfo->mNeighbors.Remove(key);
}
}
void NetlinkService::OnRouteCheckResult(struct nlmsghdr* aNlh) {
LOG(("NetlinkService::OnRouteCheckResult"));
UniquePtr<NetlinkRoute> route;
if (aNlh) {
route = MakeUnique<NetlinkRoute>();
if (!route->Init(aNlh)) {
route = nullptr;
} else {
if (!route->IsUnicast() || !route->ScopeIsUniverse()) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Not an unicast global route: %s", routeDbgStr.get()));
}
route = nullptr;
} else if (!route->HasOif()) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("There is no output interface in route: %s", routeDbgStr.get()));
}
route = nullptr;
}
}
}
if (LOG_ENABLED()) {
if (route) {
nsAutoCString routeDbgStr;
route->GetAsString(routeDbgStr);
LOG(("Storing route: %s", routeDbgStr.get()));
} else {
LOG(("Clearing result for the check"));
}
}
if (mOutgoingMessages[0]->Family() == AF_INET) {
mIPv4RouteCheckResult = std::move(route);
} else {
mIPv6RouteCheckResult = std::move(route);
}
}
void NetlinkService::EnqueueGenMsg(uint16_t aMsgType, uint8_t aFamily) {
NetlinkGenMsg* msg = new NetlinkGenMsg(aMsgType, aFamily, ++mMsgId);
mOutgoingMessages.AppendElement(msg);
}
void NetlinkService::EnqueueRtMsg(uint8_t aFamily, void* aAddress) {
NetlinkRtMsg* msg = new NetlinkRtMsg(aFamily, aAddress, ++mMsgId);
mOutgoingMessages.AppendElement(msg);
}
void NetlinkService::RemovePendingMsg() {
LOG(("NetlinkService::RemovePendingMsg [seqId=%u]",
mOutgoingMessages[0]->SeqId()));
MOZ_ASSERT(mOutgoingMessages[0]->IsPending());
DebugOnly<bool> isRtMessage =
(mOutgoingMessages[0]->MsgType() == NetlinkMsg::kRtMsg);
mOutgoingMessages.RemoveElementAt(0);
if (!mOutgoingMessages.Length()) {
if (!mInitialScanFinished) {
// Now we've received all initial data from the kernel. Perform a link
// check and trigger network ID calculation even if it wasn't triggered
// by the incoming messages.
mInitialScanFinished = true;
TriggerNetworkIDCalculation();
// Link status should be known by now.
RefPtr<NetlinkServiceListener> listener;
{
MutexAutoLock lock(mMutex);
listener = mListener;
}
if (listener) {
listener->OnLinkStatusKnown();
}
} else {
// We've received last response for route check, calculate ID now
MOZ_ASSERT(isRtMessage);
CalculateNetworkID();
}
}
}
NS_IMETHODIMP
NetlinkService::Run() {
int netlinkSocket = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (netlinkSocket < 0) {
return NS_ERROR_FAILURE;
}
struct sockaddr_nl addr {};
memset(&addr, 0, sizeof(addr));
addr.nl_family = AF_NETLINK;
addr.nl_groups = RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR | RTMGRP_LINK |
RTMGRP_NEIGH | RTMGRP_IPV4_ROUTE | RTMGRP_IPV6_ROUTE;
if (bind(netlinkSocket, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
// failure!
EINTR_RETRY(close(netlinkSocket));
return NS_ERROR_FAILURE;
}
struct pollfd fds[2];
fds[0].fd = mShutdownPipe[0];
fds[0].events = POLLIN;
fds[0].revents = 0;
fds[1].fd = netlinkSocket;
fds[1].events = POLLIN;
fds[1].revents = 0;
// send all requests to get initial network information
EnqueueGenMsg(RTM_GETLINK, AF_PACKET);
EnqueueGenMsg(RTM_GETNEIGH, AF_INET);
EnqueueGenMsg(RTM_GETNEIGH, AF_INET6);
EnqueueGenMsg(RTM_GETADDR, AF_PACKET);
EnqueueGenMsg(RTM_GETROUTE, AF_PACKET);
nsresult rv = NS_OK;
bool shutdown = false;
while (!shutdown) {
if (mOutgoingMessages.Length() && !mOutgoingMessages[0]->IsPending()) {
if (!mOutgoingMessages[0]->Send(netlinkSocket)) {
LOG(("Failed to send netlink message"));
mOutgoingMessages.RemoveElementAt(0);
// try to send another message if available before polling
continue;
}
}
int rc = eintr_retry([&]() {
AUTO_PROFILER_THREAD_SLEEP;
return poll(fds, 2, GetPollWait());
});
if (rc > 0) {
if (fds[0].revents & POLLIN) {
// shutdown, abort the loop!
LOG(("thread shutdown received, dying...\n"));
shutdown = true;
} else if (fds[1].revents & POLLIN) {
LOG(("netlink message received, handling it...\n"));
OnNetlinkMessage(netlinkSocket);
}
} else if (rc < 0) {
rv = NS_ERROR_FAILURE;
break;
}
}
EINTR_RETRY(close(netlinkSocket));
return rv;
}
nsresult NetlinkService::Init(NetlinkServiceListener* aListener) {
nsresult rv;
mListener = aListener;
if (inet_pton(AF_INET, ROUTE_CHECK_IPV4, &mRouteCheckIPv4) != 1) {
LOG(("Cannot parse address " ROUTE_CHECK_IPV4));
MOZ_DIAGNOSTIC_CRASH("Cannot parse address " ROUTE_CHECK_IPV4);
return NS_ERROR_UNEXPECTED;
}
if (inet_pton(AF_INET6, ROUTE_CHECK_IPV6, &mRouteCheckIPv6) != 1) {
LOG(("Cannot parse address " ROUTE_CHECK_IPV6));
MOZ_DIAGNOSTIC_CRASH("Cannot parse address " ROUTE_CHECK_IPV6);
return NS_ERROR_UNEXPECTED;
}
if (pipe(mShutdownPipe) == -1) {
LOG(("Cannot create pipe"));
return NS_ERROR_FAILURE;
}
rv = NS_NewNamedThread("Netlink Monitor", getter_AddRefs(mThread), this);
NS_ENSURE_SUCCESS(rv, rv);
return NS_OK;
}
nsresult NetlinkService::Shutdown() {
LOG(("write() to signal thread shutdown\n"));
{
MutexAutoLock lock(mMutex);
mListener = nullptr;
}
// awake the thread to make it terminate
ssize_t rc = EINTR_RETRY(write(mShutdownPipe[1], "1", 1));
LOG(("write() returned %d, errno == %d\n", (int)rc, errno));
nsresult rv = mThread->Shutdown();
// Have to break the cycle here, otherwise NetlinkService holds
// onto the thread and the thread holds onto the NetlinkService
// via its mRunnable
mThread = nullptr;
return rv;
}
/*
* A network event that might change network ID has been registered. Delay
* network ID calculation and sending of the event in case it changed for
* a while. Absorbing potential subsequent events increases chance of successful
* network ID calculation (e.g. MAC address of the router might be discovered in
* the meantime)
*/
void NetlinkService::TriggerNetworkIDCalculation() {
LOG(("NetlinkService::TriggerNetworkIDCalculation"));
if (mRecalculateNetworkId) {
return;
}
mRecalculateNetworkId = true;
mTriggerTime = TimeStamp::Now();
}
int NetlinkService::GetPollWait() {
if (!mRecalculateNetworkId) {
return -1;
}
if (mOutgoingMessages.Length()) {
MOZ_ASSERT(mOutgoingMessages[0]->IsPending());
// Message is pending, we don't have to set timeout because we'll receive
// reply from kernel ASAP
return -1;
}
MOZ_ASSERT(mInitialScanFinished);
double period = (TimeStamp::Now() - mTriggerTime).ToMilliseconds();
if (period >= kNetworkChangeCoalescingPeriod) {
// Coalescing time has elapsed, send route check messages to find out
// where IPv4 and IPv6 traffic is routed and calculate network ID after
// the response is received.
EnqueueRtMsg(AF_INET, &mRouteCheckIPv4);
EnqueueRtMsg(AF_INET6, &mRouteCheckIPv6);
// Return 0 to make sure we start sending enqueued messages immediately
return 0;
}
return static_cast<int>(kNetworkChangeCoalescingPeriod - period);
}
class NeighborComparator {
public:
bool Equals(const NetlinkNeighbor* a, const NetlinkNeighbor* b) const {
return (memcmp(a->GetMACPtr(), b->GetMACPtr(), ETH_ALEN) == 0);
}
bool LessThan(const NetlinkNeighbor* a, const NetlinkNeighbor* b) const {
return (memcmp(a->GetMACPtr(), b->GetMACPtr(), ETH_ALEN) < 0);
}
};
class LinknameComparator {
public:
bool LessThan(const nsCString& aA, const nsCString& aB) const {
return aA < aB;
}
bool Equals(const nsCString& aA, const nsCString& aB) const {
return aA == aB;
}
};
// Get Gateway Neighbours for a particular Address Family, for which we know MAC
// address
void NetlinkService::GetGWNeighboursForFamily(
uint8_t aFamily, nsTArray<NetlinkNeighbor*>& aGwNeighbors) {
LOG(("NetlinkService::GetGWNeighboursForFamily"));
// Check only routes on links that are up
for (const auto& linkInfo : mLinks.Values()) {
nsAutoCString linkName;
linkInfo->mLink->GetName(linkName);
if (!linkInfo->mIsUp) {
LOG((" %s is down", linkName.get()));
continue;
}
if (!linkInfo->mLink->IsTypeEther()) {
LOG((" %s is not ethernet link", linkName.get()));
continue;
}
LOG((" checking link %s", linkName.get()));
// Check all default routes and try to get MAC of the gateway
for (uint32_t i = 0; i < linkInfo->mDefaultRoutes.Length(); ++i) {
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
linkInfo->mDefaultRoutes[i]->GetAsString(routeDbgStr);
LOG(("Checking default route: %s", routeDbgStr.get()));
}
if (linkInfo->mDefaultRoutes[i]->Family() != aFamily) {
LOG((" skipping due to different family"));
continue;
}
MOZ_ASSERT(linkInfo->mDefaultRoutes[i]->GetGWAddrPtr(),
"Stored routes must have gateway!");
nsAutoCString neighKey;
GetAddrStr(linkInfo->mDefaultRoutes[i]->GetGWAddrPtr(), aFamily,
neighKey);
NetlinkNeighbor* neigh = nullptr;
if (!linkInfo->mNeighbors.Get(neighKey, &neigh)) {
LOG(("Neighbor %s not found in hashtable.", neighKey.get()));
continue;
}
if (!neigh->HasMAC()) {
// We don't know MAC address
LOG(("We have no MAC for neighbor %s.", neighKey.get()));
continue;
}
if (aGwNeighbors.IndexOf(neigh, 0, NeighborComparator()) !=
nsTArray<NetlinkNeighbor*>::NoIndex) {
// avoid host duplicities
LOG(("MAC of neighbor %s is already selected for hashing.",
neighKey.get()));
continue;
}
LOG(("MAC of neighbor %s will be used for network ID.", neighKey.get()));
aGwNeighbors.AppendElement(neigh);
}
}
}
bool NetlinkService::CalculateIDForEthernetLink(uint8_t aFamily,
NetlinkRoute* aRouteCheckResult,
uint32_t aRouteCheckIfIdx,
LinkInfo* aRouteCheckLinkInfo,
SHA1Sum* aSHA1) {
LOG(("NetlinkService::CalculateIDForEthernetLink"));
bool retval = false;
const in_common_addr* addrPtr = aRouteCheckResult->GetGWAddrPtr();
if (!addrPtr) {
// This shouldn't normally happen, missing next hop in case of ethernet
// device would mean that the checked host is on the same network.
if (LOG_ENABLED()) {
nsAutoCString routeDbgStr;
aRouteCheckResult->GetAsString(routeDbgStr);
LOG(("There is no next hop in route: %s", routeDbgStr.get()));
}
return retval;
}
// If we know MAC address of the next hop for mRouteCheckIPv4/6 host, hash
// it even if it's MAC of some of the default routes we've checked above.
// This ensures that if we have 2 different default routes and next hop for
// mRouteCheckIPv4/6 changes from one default route to the other, we'll
// detect it as a network change.
nsAutoCString neighKey;
GetAddrStr(addrPtr, aFamily, neighKey);
LOG(("Next hop for the checked host is %s on ifIdx %u.", neighKey.get(),
aRouteCheckIfIdx));
NetlinkNeighbor* neigh = nullptr;
if (!aRouteCheckLinkInfo->mNeighbors.Get(neighKey, &neigh)) {
LOG(("Neighbor %s not found in hashtable.", neighKey.get()));
return retval;
}
if (!neigh->HasMAC()) {
LOG(("We have no MAC for neighbor %s.", neighKey.get()));
return retval;
}
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
neigh->GetAsString(neighDbgStr);
LOG(("Hashing MAC address of neighbor: %s", neighDbgStr.get()));
}
aSHA1->update(neigh->GetMACPtr(), ETH_ALEN);
retval = true;
return retval;
}
bool NetlinkService::CalculateIDForNonEthernetLink(
uint8_t aFamily, NetlinkRoute* aRouteCheckResult,
nsTArray<nsCString>& aLinkNamesToHash, uint32_t aRouteCheckIfIdx,
LinkInfo* aRouteCheckLinkInfo, SHA1Sum* aSHA1) {
LOG(("NetlinkService::CalculateIDForNonEthernetLink"));
bool retval = false;
const in_common_addr* addrPtr = aRouteCheckResult->GetGWAddrPtr();
nsAutoCString routeCheckLinkName;
aRouteCheckLinkInfo->mLink->GetName(routeCheckLinkName);
if (addrPtr) {
// The route contains next hop. Hash the name of the interface (e.g.
// "tun1") and the IP address of the next hop.
nsAutoCString addrStr;
GetAddrStr(addrPtr, aFamily, addrStr);
size_t addrSize =
(aFamily == AF_INET) ? sizeof(addrPtr->addr4) : sizeof(addrPtr->addr6);
LOG(("Hashing link name %s", routeCheckLinkName.get()));
aSHA1->update(routeCheckLinkName.get(), routeCheckLinkName.Length());
// Don't hash GW address if it's rmnet_data device.
if (!aLinkNamesToHash.Contains(routeCheckLinkName)) {
LOG(("Hashing GW address %s", addrStr.get()));
aSHA1->update(addrPtr, addrSize);
}
retval = true;
} else {
// The traffic is routed directly via an interface. Hash the name of the
// interface and the network address. Using host address would cause that
// network ID would be different every time we get a different IP address
// in this network/VPN.
bool hasSrcAddr = aRouteCheckResult->HasPrefSrcAddr();
if (!hasSrcAddr) {
LOG(("There is no preferred source address."));
}
NetlinkAddress* linkAddress = nullptr;
// Find network address of the interface matching the source address. In
// theory there could be multiple addresses with different prefix length.
// Get the one with smallest prefix length.
for (uint32_t i = 0; i < aRouteCheckLinkInfo->mAddresses.Length(); ++i) {
if (!hasSrcAddr) {
// there is no preferred src, match just the family
if (aRouteCheckLinkInfo->mAddresses[i]->Family() != aFamily) {
continue;
}
} else if (!aRouteCheckResult->PrefSrcAddrEquals(
*aRouteCheckLinkInfo->mAddresses[i])) {
continue;
}
if (!linkAddress ||
linkAddress->GetPrefixLen() >
aRouteCheckLinkInfo->mAddresses[i]->GetPrefixLen()) {
// We have no address yet or this one has smaller prefix length,
// use it.
linkAddress = aRouteCheckLinkInfo->mAddresses[i].get();
}
}
if (!linkAddress) {
// There is no address in our array?
if (LOG_ENABLED()) {
nsAutoCString dbgStr;
aRouteCheckResult->GetAsString(dbgStr);
LOG(("No address found for preferred source address in route: %s",
dbgStr.get()));
}
return retval;
}
in_common_addr prefix;
int32_t prefixSize = (aFamily == AF_INET) ? (int32_t)sizeof(prefix.addr4)
: (int32_t)sizeof(prefix.addr6);
memcpy(&prefix, linkAddress->GetAddrPtr(), prefixSize);
uint8_t maskit[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe};
int32_t bits = linkAddress->GetPrefixLen();
if (bits > prefixSize * 8) {
MOZ_ASSERT(false, "Unexpected prefix length!");
LOG(("Unexpected prefix length %d, maximum for this family is %d", bits,
prefixSize * 8));
return retval;
}
for (int32_t i = 0; i < prefixSize; i++) {
uint8_t mask = (bits >= 8) ? 0xff : maskit[bits];
((unsigned char*)&prefix)[i] &= mask;
bits -= 8;
if (bits <= 0) {
bits = 0;
}
}
nsAutoCString addrStr;
GetAddrStr(&prefix, aFamily, addrStr);
LOG(("Hashing link name %s and network address %s/%u",
routeCheckLinkName.get(), addrStr.get(), linkAddress->GetPrefixLen()));
aSHA1->update(routeCheckLinkName.get(), routeCheckLinkName.Length());
aSHA1->update(&prefix, prefixSize);
bits = linkAddress->GetPrefixLen();
aSHA1->update(&bits, sizeof(bits));
retval = true;
}
return retval;
}
bool NetlinkService::CalculateIDForFamily(uint8_t aFamily, SHA1Sum* aSHA1) {
LOG(("NetlinkService::CalculateIDForFamily [family=%s]",
aFamily == AF_INET ? "AF_INET" : "AF_INET6"));
bool retval = false;
if (!mLinkUp) {
// Skip ID calculation if the link is down, we have no ID...
LOG(("Link is down, skipping ID calculation."));
return retval;
}
NetlinkRoute* routeCheckResult;
if (aFamily == AF_INET) {
routeCheckResult = mIPv4RouteCheckResult.get();
} else {
routeCheckResult = mIPv6RouteCheckResult.get();
}
// All GW neighbors for which we know MAC address. We'll probably have at
// most only one, but in case we have more default routes, we hash them all
// even though the routing rules sends the traffic only via one of them.
// If the system switches between them, we'll detect the change with
// mIPv4/6RouteCheckResult.
nsTArray<NetlinkNeighbor*> gwNeighbors;
GetGWNeighboursForFamily(aFamily, gwNeighbors);
// Sort them so we always have the same network ID on the same network
gwNeighbors.Sort(NeighborComparator());
for (uint32_t i = 0; i < gwNeighbors.Length(); ++i) {
if (LOG_ENABLED()) {
nsAutoCString neighDbgStr;
gwNeighbors[i]->GetAsString(neighDbgStr);
LOG(("Hashing MAC address of neighbor: %s", neighDbgStr.get()));
}
aSHA1->update(gwNeighbors[i]->GetMACPtr(), ETH_ALEN);
retval = true;
}
nsTArray<nsCString> linkNamesToHash;
if (!gwNeighbors.Length()) {
// If we don't know MAC of the gateway and link is up, it's probably not
// an ethernet link. If the name of the link begins with "rmnet" then
// the mobile data is used. We cannot easily differentiate when user
// switches sim cards so let's treat mobile data as a single network. We'll
// simply hash link name. If the traffic is redirected via some VPN, it'll
// still be detected below.
// TODO: maybe we could get operator name via AndroidBridge
for (const auto& linkInfo : mLinks.Values()) {
if (linkInfo->mIsUp) {
nsAutoCString linkName;
linkInfo->mLink->GetName(linkName);
if (StringBeginsWith(linkName, "rmnet"_ns)) {
// Check whether there is some non-local address associated with this
// link.
for (uint32_t i = 0; i < linkInfo->mAddresses.Length(); ++i) {
if (linkInfo->mAddresses[i]->Family() == aFamily &&
linkInfo->mAddresses[i]->ScopeIsUniverse()) {
linkNamesToHash.AppendElement(linkName);
break;
}
}
}
}
}
// Sort link names to ensure consistent results
linkNamesToHash.Sort(LinknameComparator());
for (uint32_t i = 0; i < linkNamesToHash.Length(); ++i) {
LOG(("Hashing name of adapter: %s", linkNamesToHash[i].get()));
aSHA1->update(linkNamesToHash[i].get(), linkNamesToHash[i].Length());
retval = true;
}
}
if (!routeCheckResult) {
// If we don't have result for route check to mRouteCheckIPv4/6 host, the
// network is unreachable and there is no more to do.
LOG(("There is no route check result."));
return retval;
}
LinkInfo* routeCheckLinkInfo = nullptr;
uint32_t routeCheckIfIdx = routeCheckResult->Oif();
if (!mLinks.Get(routeCheckIfIdx, &routeCheckLinkInfo)) {
LOG(("Cannot find link with index %u ??", routeCheckIfIdx));
return retval;
}
if (routeCheckLinkInfo->mLink->IsTypeEther()) {
// The traffic is routed through an ethernet device.
retval |= CalculateIDForEthernetLink(
aFamily, routeCheckResult, routeCheckIfIdx, routeCheckLinkInfo, aSHA1);
} else {
// The traffic is routed through a non-ethernet device.
retval |= CalculateIDForNonEthernetLink(aFamily, routeCheckResult,
linkNamesToHash, routeCheckIfIdx,
routeCheckLinkInfo, aSHA1);
}
return retval;
}
void NetlinkService::ExtractDNSProperties() {
MOZ_ASSERT(!NS_IsMainThread(), "Must not be called on the main thread");
nsTArray<nsCString> suffixList;
nsTArray<NetAddr> resolvers;
#if defined(HAVE_RES_NINIT)
[&]() {
struct __res_state res {};
int ret = res_ninit(&res);
if (ret != 0) {
LOG(("Call to res_ninit failed: %d", ret));
return;
}
// Get DNS suffixes
for (int i = 0; i < MAXDNSRCH; i++) {
if (!res.dnsrch[i]) {
break;
}
suffixList.AppendElement(nsCString(res.dnsrch[i]));
}
// Get DNS resolvers
// Chromium's dns_config_service_posix.cc is the origin of this code
// Initially, glibc stores IPv6 in |_ext.nsaddrs| and IPv4 in |nsaddr_list|.
// In res_send.c:res_nsend, it merges |nsaddr_list| into |nsaddrs|,
// but we have to combine the two arrays ourselves.
for (int i = 0; i < res.nscount; ++i) {
const struct sockaddr* addr = nullptr;
size_t addr_len = 0;
if (res.nsaddr_list[i].sin_family) { // The indicator used by res_nsend.
addr = reinterpret_cast<const struct sockaddr*>(&res.nsaddr_list[i]);
addr_len = sizeof res.nsaddr_list[i];
} else if (res._u._ext.nsaddrs[i]) {
addr = reinterpret_cast<const struct sockaddr*>(res._u._ext.nsaddrs[i]);
addr_len = sizeof *res._u._ext.nsaddrs[i];
} else {
LOG(("Bad ext struct"));
return;
}
const socklen_t kSockaddrInSize = sizeof(struct sockaddr_in);
const socklen_t kSockaddrIn6Size = sizeof(struct sockaddr_in6);
if ((addr->sa_family == AF_INET && addr_len < kSockaddrInSize) ||
(addr->sa_family == AF_INET6 && addr_len < kSockaddrIn6Size)) {
LOG(("Bad address size"));
return;
}
NetAddr ip;
if (addr->sa_family == AF_INET) {
const struct sockaddr_in* sin = (const struct sockaddr_in*)addr;
ip.inet.family = AF_INET;
ip.inet.ip = sin->sin_addr.s_addr;
ip.inet.port = sin->sin_port;
} else if (addr->sa_family == AF_INET6) {
const struct sockaddr_in6* sin6 = (const struct sockaddr_in6*)addr;
ip.inet6.family = AF_INET6;
memcpy(&ip.inet6.ip.u8, &sin6->sin6_addr, sizeof(ip.inet6.ip.u8));
ip.inet6.port = sin6->sin6_port;
} else {
MOZ_ASSERT_UNREACHABLE("Unexpected sa_family");
return;
}
resolvers.AppendElement(ip);
}
res_nclose(&res);
}();
#endif
RefPtr<NetlinkServiceListener> listener;
{
MutexAutoLock lock(mMutex);
listener = mListener;
mDNSSuffixList = std::move(suffixList);
mDNSResolvers = std::move(resolvers);
}
if (listener) {
listener->OnDnsSuffixListUpdated();
}
}
void NetlinkService::UpdateLinkStatus() {
LOG(("NetlinkService::UpdateLinkStatus"));
MOZ_ASSERT(!mRecalculateNetworkId);
MOZ_ASSERT(mInitialScanFinished);
// Link is up when we have a route for ROUTE_CHECK_IPV4 or ROUTE_CHECK_IPV6
bool newLinkUp = mIPv4RouteCheckResult || mIPv6RouteCheckResult;
if (mLinkUp == newLinkUp) {
LOG(("Link status hasn't changed [linkUp=%d]", mLinkUp));
} else {
LOG(("Link status has changed [linkUp=%d]", newLinkUp));
RefPtr<NetlinkServiceListener> listener;
{
MutexAutoLock lock(mMutex);
listener = mListener;
mLinkUp = newLinkUp;
}
if (mLinkUp) {
if (listener) {
listener->OnLinkUp();
}
} else {
if (listener) {
listener->OnLinkDown();
}
}
}
}
// Figure out the "network identification".
void NetlinkService::CalculateNetworkID() {
LOG(("NetlinkService::CalculateNetworkID"));
MOZ_ASSERT(!NS_IsMainThread(), "Must not be called on the main thread");
MOZ_ASSERT(mRecalculateNetworkId);
mRecalculateNetworkId = false;
SHA1Sum sha1;
UpdateLinkStatus();
ExtractDNSProperties();
bool idChanged = false;
bool found4 = CalculateIDForFamily(AF_INET, &sha1);
bool found6 = CalculateIDForFamily(AF_INET6, &sha1);
if (found4 || found6) {
nsAutoCString output;
SeedNetworkId(sha1);
uint8_t digest[SHA1Sum::kHashSize];
sha1.finish(digest);
nsAutoCString newString(reinterpret_cast<char*>(digest),
SHA1Sum::kHashSize);
nsresult rv = Base64Encode(newString, output);
MOZ_RELEASE_ASSERT(NS_SUCCEEDED(rv));
LOG(("networkid: id %s\n", output.get()));
MutexAutoLock lock(mMutex);
if (mNetworkId != output) {
// new id
if (found4 && !found6) {
Telemetry::Accumulate(Telemetry::NETWORK_ID2, 1); // IPv4 only
} else if (!found4 && found6) {
Telemetry::Accumulate(Telemetry::NETWORK_ID2, 3); // IPv6 only
} else {
Telemetry::Accumulate(Telemetry::NETWORK_ID2, 4); // Both!
}
mNetworkId = output;
idChanged = true;
} else {
// same id
LOG(("Same network id"));
Telemetry::Accumulate(Telemetry::NETWORK_ID2, 2);
}
} else {
// no id
LOG(("No network id"));
MutexAutoLock lock(mMutex);
if (!mNetworkId.IsEmpty()) {
mNetworkId.Truncate();
idChanged = true;
Telemetry::Accumulate(Telemetry::NETWORK_ID2, 0);
}
}
if (idChanged) {
sHasNonLocalIPv6 = found6;
LOG(("has IPv6: %d", bool(sHasNonLocalIPv6)));
}
// If this is first time we calculate network ID, don't report it as a network
// change. We've started with an empty ID and we've just calculated the
// correct ID. The network hasn't really changed.
static bool initialIDCalculation = true;
RefPtr<NetlinkServiceListener> listener;
{
MutexAutoLock lock(mMutex);
listener = mListener;
}
if (!initialIDCalculation && idChanged && listener) {
listener->OnNetworkIDChanged();
mSendNetworkChangeEvent = true;
}
if (mSendNetworkChangeEvent && listener) {
listener->OnNetworkChanged();
}
initialIDCalculation = false;
mSendNetworkChangeEvent = false;
}
void NetlinkService::GetNetworkID(nsACString& aNetworkID) {
MutexAutoLock lock(mMutex);
aNetworkID = mNetworkId;
}
nsresult NetlinkService::GetDnsSuffixList(nsTArray<nsCString>& aDnsSuffixList) {
#if defined(HAVE_RES_NINIT)
MutexAutoLock lock(mMutex);
aDnsSuffixList = mDNSSuffixList.Clone();
return NS_OK;
#else
return NS_ERROR_NOT_IMPLEMENTED;
#endif
}
nsresult NetlinkService::GetResolvers(nsTArray<NetAddr>& aResolvers) {
#if defined(HAVE_RES_NINIT)
MutexAutoLock lock(mMutex);
aResolvers = mDNSResolvers.Clone();
return NS_OK;
#else
return NS_ERROR_NOT_IMPLEMENTED;
#endif
}
void NetlinkService::GetIsLinkUp(bool* aIsUp) {
MutexAutoLock lock(mMutex);
*aIsUp = mLinkUp;
}
} // namespace mozilla::net