netwerk/base/nsProtocolProxyService.cpp
author Carsten "Tomcat" Book <cbook@mozilla.com>
Tue, 02 Jun 2015 13:05:56 +0200
changeset 279080 3c8ed81098ddbe4a4c09e7aa652b5288dc4ce0d3
parent 279055 7c3b45a47811b55f4e973d996dd149c5d575721b
child 279432 f52c18aac7ce0949190da943ec5d4ee86627d0f8
permissions -rw-r--r--
Backed out 14 changesets (bug 1165515) for linux x64 e10s m2 test failures Backed out changeset d68dcf2ef372 (bug 1165515) Backed out changeset 7c3b45a47811 (bug 1165515) Backed out changeset b668b617bef2 (bug 1165515) Backed out changeset d0916e1283a2 (bug 1165515) Backed out changeset ac4dc7489942 (bug 1165515) Backed out changeset e9632ce8bc65 (bug 1165515) Backed out changeset c16d215cc7e4 (bug 1165515) Backed out changeset e4d474f3c51a (bug 1165515) Backed out changeset d87680bf9f7c (bug 1165515) Backed out changeset b3c0a45ba99e (bug 1165515) Backed out changeset 9370fa197674 (bug 1165515) Backed out changeset 50970d668ca1 (bug 1165515) Backed out changeset ffa4eb6d24b9 (bug 1165515) Backed out changeset 5fcf1203cc1d (bug 1165515)

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim:set ts=4 sw=4 sts=4 et: */
/* 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
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/ArrayUtils.h"
#include "mozilla/Attributes.h"

#include "nsProtocolProxyService.h"
#include "nsProxyInfo.h"
#include "nsIClassInfoImpl.h"
#include "nsIIOService.h"
#include "nsIObserverService.h"
#include "nsIProtocolHandler.h"
#include "nsIProtocolProxyCallback.h"
#include "nsIChannel.h"
#include "nsICancelable.h"
#include "nsIDNSService.h"
#include "nsPIDNSService.h"
#include "nsIScriptSecurityManager.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch.h"
#include "nsThreadUtils.h"
#include "nsString.h"
#include "nsNetUtil.h"
#include "nsNetCID.h"
#include "prnetdb.h"
#include "nsPACMan.h"
#include "nsProxyRelease.h"
#include "mozilla/Mutex.h"
#include "mozilla/CondVar.h"
#include "nsISystemProxySettings.h"
#include "nsINetworkLinkService.h"
#include "nsIHttpChannelInternal.h"

//----------------------------------------------------------------------------

namespace mozilla {
  extern const char kProxyType_HTTP[];
  extern const char kProxyType_HTTPS[];
  extern const char kProxyType_SOCKS[];
  extern const char kProxyType_SOCKS4[];
  extern const char kProxyType_SOCKS5[];
  extern const char kProxyType_DIRECT[];
}

using namespace mozilla;

#include "mozilla/Logging.h"
#undef LOG
#define LOG(args) MOZ_LOG(net::GetProxyLog(), PR_LOG_DEBUG, args)

//----------------------------------------------------------------------------

#define PROXY_PREF_BRANCH  "network.proxy"
#define PROXY_PREF(x)      PROXY_PREF_BRANCH "." x

#define WPAD_URL "http://wpad/wpad.dat"

//----------------------------------------------------------------------------

// This structure is intended to be allocated on the stack
struct nsProtocolInfo {
    nsAutoCString scheme;
    uint32_t flags;
    int32_t defaultPort;
};

//----------------------------------------------------------------------------

// Return the channel's proxy URI, or if it doesn't exist, the
// channel's main URI.
static nsresult
GetProxyURI(nsIChannel *channel, nsIURI **aOut)
{
  nsresult rv;
  nsCOMPtr<nsIURI> proxyURI;
  nsCOMPtr<nsIHttpChannelInternal> httpChannel(do_QueryInterface(channel));
  if (httpChannel) {
    rv = httpChannel->GetProxyURI(getter_AddRefs(proxyURI));
  }
  if (!proxyURI) {
    rv = channel->GetURI(getter_AddRefs(proxyURI));
  }
  if (NS_FAILED(rv)) {
    return rv;
  }
  proxyURI.forget(aOut);
  return NS_OK;
}

//-----------------------------------------------------------------------------

// The nsPACManCallback portion of this implementation should be run
// on the main thread - so call nsPACMan::AsyncGetProxyForURI() with
// a true mainThreadResponse parameter.
class nsAsyncResolveRequest final : public nsIRunnable
                                  , public nsPACManCallback
                                  , public nsICancelable
{
public:
    NS_DECL_THREADSAFE_ISUPPORTS

    nsAsyncResolveRequest(nsProtocolProxyService *pps, nsIChannel *channel,
                          uint32_t aAppId, bool aIsInBrowser,
                          uint32_t aResolveFlags,
                          nsIProtocolProxyCallback *callback)
        : mStatus(NS_OK)
        , mDispatched(false)
        , mResolveFlags(aResolveFlags)
        , mPPS(pps)
        , mXPComPPS(pps)
        , mChannel(channel)
        , mAppId(aAppId)
        , mIsInBrowser(aIsInBrowser)
        , mCallback(callback)
    {
        NS_ASSERTION(mCallback, "null callback");
    }

private:
    ~nsAsyncResolveRequest()
    {
        if (!NS_IsMainThread()) {
            // these xpcom pointers might need to be proxied back to the
            // main thread to delete safely, but if this request had its
            // callbacks called normally they will all be null and this is a nop

            nsCOMPtr<nsIThread> mainThread;
            NS_GetMainThread(getter_AddRefs(mainThread));

            if (mChannel) {
                nsIChannel *forgettable;
                mChannel.forget(&forgettable);
                NS_ProxyRelease(mainThread, forgettable, false);
            }

            if (mCallback) {
                nsIProtocolProxyCallback *forgettable;
                mCallback.forget(&forgettable);
                NS_ProxyRelease(mainThread, forgettable, false);
            }

            if (mProxyInfo) {
                nsIProxyInfo *forgettable;
                mProxyInfo.forget(&forgettable);
                NS_ProxyRelease(mainThread, forgettable, false);
            }

            if (mXPComPPS) {
                nsIProtocolProxyService *forgettable;
                mXPComPPS.forget(&forgettable);
                NS_ProxyRelease(mainThread, forgettable, false);
            }
        }
    }

public:
    void SetResult(nsresult status, nsIProxyInfo *pi)
    {
        mStatus = status;
        mProxyInfo = pi;
    }

    NS_IMETHOD Run() override
    {
        if (mCallback)
            DoCallback();
        return NS_OK;
    }

    NS_IMETHOD Cancel(nsresult reason) override
    {
        NS_ENSURE_ARG(NS_FAILED(reason));

        // If we've already called DoCallback then, nothing more to do.
        if (!mCallback)
            return NS_OK;

        SetResult(reason, nullptr);
        return DispatchCallback();
    }

    nsresult DispatchCallback()
    {
        if (mDispatched)  // Only need to dispatch once
            return NS_OK;

        nsresult rv = NS_DispatchToCurrentThread(this);
        if (NS_FAILED(rv))
            NS_WARNING("unable to dispatch callback event");
        else {
            mDispatched = true;
            return NS_OK;
        }

        mCallback = nullptr;  // break possible reference cycle
        return rv;
    }

private:

    // Called asynchronously, so we do not need to post another PLEvent
    // before calling DoCallback.
    void OnQueryComplete(nsresult status,
                         const nsCString &pacString,
                         const nsCString &newPACURL) override
    {
        // If we've already called DoCallback then, nothing more to do.
        if (!mCallback)
            return;

        // Provided we haven't been canceled...
        if (mStatus == NS_OK) {
            mStatus = status;
            mPACString = pacString;
            mPACURL = newPACURL;
        }

        // In the cancelation case, we may still have another PLEvent in
        // the queue that wants to call DoCallback.  No need to wait for
        // it, just run the callback now.
        DoCallback();
    }

    void DoCallback()
    {
        if (mStatus == NS_ERROR_NOT_AVAILABLE && !mProxyInfo) {
            // If the PAC service is not avail (e.g. failed pac load
            // or shutdown) then we will be going direct. Make that
            // mapping now so that any filters are still applied.
            mPACString = NS_LITERAL_CSTRING("DIRECT;");
            mStatus = NS_OK;
        }

        // Generate proxy info from the PAC string if appropriate
        if (NS_SUCCEEDED(mStatus) && !mProxyInfo && !mPACString.IsEmpty()) {
            mPPS->ProcessPACString(mPACString, mResolveFlags,
                                   getter_AddRefs(mProxyInfo));
            nsCOMPtr<nsIURI> proxyURI;
            GetProxyURI(mChannel, getter_AddRefs(proxyURI));

            // Now apply proxy filters
            nsProtocolInfo info;
            mStatus = mPPS->GetProtocolInfo(proxyURI, &info);
            if (NS_SUCCEEDED(mStatus))
                mPPS->ApplyFilters(mChannel, info, mProxyInfo);
            else
                mProxyInfo = nullptr;

            LOG(("pac thread callback %s\n", mPACString.get()));
            if (NS_SUCCEEDED(mStatus))
                mPPS->MaybeDisableDNSPrefetch(mProxyInfo);
            mCallback->OnProxyAvailable(this, mChannel, mProxyInfo, mStatus);
        }
        else if (NS_SUCCEEDED(mStatus) && !mPACURL.IsEmpty()) {
            LOG(("pac thread callback indicates new pac file load\n"));

            nsCOMPtr<nsIURI> proxyURI;
            GetProxyURI(mChannel, getter_AddRefs(proxyURI));

            // trigger load of new pac url
            nsresult rv = mPPS->ConfigureFromPAC(mPACURL, false);
            if (NS_SUCCEEDED(rv)) {
                // now that the load is triggered, we can resubmit the query
                nsRefPtr<nsAsyncResolveRequest> newRequest =
                    new nsAsyncResolveRequest(mPPS, mChannel, mAppId,
                                              mIsInBrowser, mResolveFlags,
                                              mCallback);
                rv = mPPS->mPACMan->AsyncGetProxyForURI(proxyURI, mAppId,
                                                        mIsInBrowser,
                                                        newRequest,
                                                        true);
            }

            if (NS_FAILED(rv))
                mCallback->OnProxyAvailable(this, mChannel, nullptr, rv);

            // do not call onproxyavailable() in SUCCESS case - the newRequest will
            // take care of that
        }
        else {
            LOG(("pac thread callback did not provide information %X\n", mStatus));
            if (NS_SUCCEEDED(mStatus))
                mPPS->MaybeDisableDNSPrefetch(mProxyInfo);
            mCallback->OnProxyAvailable(this, mChannel, mProxyInfo, mStatus);
        }

        // We are on the main thread now and don't need these any more so
        // release them to avoid having to proxy them back to the main thread
        // in the dtor
        mCallback = nullptr;  // in case the callback holds an owning ref to us
        mPPS = nullptr;
        mXPComPPS = nullptr;
        mChannel = nullptr;
        mProxyInfo = nullptr;
    }

private:

    nsresult  mStatus;
    nsCString mPACString;
    nsCString mPACURL;
    bool      mDispatched;
    uint32_t  mResolveFlags;

    nsProtocolProxyService            *mPPS;
    nsCOMPtr<nsIProtocolProxyService>  mXPComPPS;
    nsCOMPtr<nsIChannel>               mChannel;
    uint32_t                           mAppId;
    bool                               mIsInBrowser;
    nsCOMPtr<nsIProtocolProxyCallback> mCallback;
    nsCOMPtr<nsIProxyInfo>             mProxyInfo;
};

NS_IMPL_ISUPPORTS(nsAsyncResolveRequest, nsICancelable, nsIRunnable)

//----------------------------------------------------------------------------

#define IS_ASCII_SPACE(_c) ((_c) == ' ' || (_c) == '\t')

//
// apply mask to address (zeros out excluded bits).
//
// NOTE: we do the byte swapping here to minimize overall swapping.
//
static void
proxy_MaskIPv6Addr(PRIPv6Addr &addr, uint16_t mask_len)
{
    if (mask_len == 128)
        return;

    if (mask_len > 96) {
        addr.pr_s6_addr32[3] = PR_htonl(
                PR_ntohl(addr.pr_s6_addr32[3]) & (~0L << (128 - mask_len)));
    }
    else if (mask_len > 64) {
        addr.pr_s6_addr32[3] = 0;
        addr.pr_s6_addr32[2] = PR_htonl(
                PR_ntohl(addr.pr_s6_addr32[2]) & (~0L << (96 - mask_len)));
    }
    else if (mask_len > 32) {
        addr.pr_s6_addr32[3] = 0;
        addr.pr_s6_addr32[2] = 0;
        addr.pr_s6_addr32[1] = PR_htonl(
                PR_ntohl(addr.pr_s6_addr32[1]) & (~0L << (64 - mask_len)));
    }
    else {
        addr.pr_s6_addr32[3] = 0;
        addr.pr_s6_addr32[2] = 0;
        addr.pr_s6_addr32[1] = 0;
        addr.pr_s6_addr32[0] = PR_htonl(
                PR_ntohl(addr.pr_s6_addr32[0]) & (~0L << (32 - mask_len)));
    }
}

static void
proxy_GetStringPref(nsIPrefBranch *aPrefBranch,
                    const char    *aPref,
                    nsCString     &aResult)
{
    nsXPIDLCString temp;
    nsresult rv = aPrefBranch->GetCharPref(aPref, getter_Copies(temp));
    if (NS_FAILED(rv))
        aResult.Truncate();
    else {
        aResult.Assign(temp);
        // all of our string prefs are hostnames, so we should remove any
        // whitespace characters that the user might have unknowingly entered.
        aResult.StripWhitespace();
    }
}

static void
proxy_GetIntPref(nsIPrefBranch *aPrefBranch,
                 const char    *aPref,
                 int32_t       &aResult)
{
    int32_t temp;
    nsresult rv = aPrefBranch->GetIntPref(aPref, &temp);
    if (NS_FAILED(rv))
        aResult = -1;
    else
        aResult = temp;
}

static void
proxy_GetBoolPref(nsIPrefBranch *aPrefBranch,
                 const char    *aPref,
                 bool          &aResult)
{
    bool temp;
    nsresult rv = aPrefBranch->GetBoolPref(aPref, &temp);
    if (NS_FAILED(rv))
        aResult = false;
    else
        aResult = temp;
}

//----------------------------------------------------------------------------

static const int32_t PROXYCONFIG_DIRECT4X = 3;
static const int32_t PROXYCONFIG_COUNT = 6;

NS_IMPL_ADDREF(nsProtocolProxyService)
NS_IMPL_RELEASE(nsProtocolProxyService)
NS_IMPL_CLASSINFO(nsProtocolProxyService, nullptr, nsIClassInfo::SINGLETON,
                  NS_PROTOCOLPROXYSERVICE_CID)

// NS_IMPL_QUERY_INTERFACE_CI with the nsProtocolProxyService QI change
NS_INTERFACE_MAP_BEGIN(nsProtocolProxyService)
NS_INTERFACE_MAP_ENTRY(nsIProtocolProxyService)
NS_INTERFACE_MAP_ENTRY(nsIProtocolProxyService2)
NS_INTERFACE_MAP_ENTRY(nsIObserver)
if ( aIID.Equals(NS_GET_IID(nsProtocolProxyService)) )  foundInterface = static_cast<nsIProtocolProxyService2*>(this); else
NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIProtocolProxyService)
NS_IMPL_QUERY_CLASSINFO(nsProtocolProxyService)
NS_INTERFACE_MAP_END

NS_IMPL_CI_INTERFACE_GETTER(nsProtocolProxyService,
                            nsIProtocolProxyService,
                            nsIProtocolProxyService2)

nsProtocolProxyService::nsProtocolProxyService()
    : mFilterLocalHosts(false)
    , mFilters(nullptr)
    , mProxyConfig(PROXYCONFIG_DIRECT)
    , mHTTPProxyPort(-1)
    , mFTPProxyPort(-1)
    , mHTTPSProxyPort(-1)
    , mSOCKSProxyPort(-1)
    , mSOCKSProxyVersion(4)
    , mSOCKSProxyRemoteDNS(false)
    , mProxyOverTLS(true)
    , mPACMan(nullptr)
    , mSessionStart(PR_Now())
    , mFailedProxyTimeout(30 * 60) // 30 minute default
{
}

nsProtocolProxyService::~nsProtocolProxyService()
{
    // These should have been cleaned up in our Observe method.
    NS_ASSERTION(mHostFiltersArray.Length() == 0 && mFilters == nullptr &&
                 mPACMan == nullptr, "what happened to xpcom-shutdown?");
}

// nsProtocolProxyService methods
nsresult
nsProtocolProxyService::Init()
{
    // failure to access prefs is non-fatal
    nsCOMPtr<nsIPrefBranch> prefBranch =
            do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (prefBranch) {
        // monitor proxy prefs
        prefBranch->AddObserver(PROXY_PREF_BRANCH, this, false);

        // read all prefs
        PrefsChanged(prefBranch, nullptr);
    }

    nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
    if (obs) {
        // register for shutdown notification so we can clean ourselves up
        // properly.
        obs->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, false);
        obs->AddObserver(this, NS_NETWORK_LINK_TOPIC, false);
    }

    return NS_OK;
}

// ReloadNetworkPAC() checks if there's a non-networked PAC in use then avoids
// to call ReloadPAC()
nsresult
nsProtocolProxyService::ReloadNetworkPAC()
{
    nsCOMPtr<nsIPrefBranch> prefs =
        do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (!prefs) {
        return NS_OK;
    }

    int32_t type;
    nsresult rv = prefs->GetIntPref(PROXY_PREF("type"), &type);
    if (NS_FAILED(rv)) {
        return NS_OK;
    }

    if (type == PROXYCONFIG_PAC) {
        nsXPIDLCString pacSpec;
        prefs->GetCharPref(PROXY_PREF("autoconfig_url"),
                           getter_Copies(pacSpec));
        if (!pacSpec.IsEmpty()) {
            nsCOMPtr<nsIURI> pacURI;
            rv = NS_NewURI(getter_AddRefs(pacURI), pacSpec);
            if(!NS_SUCCEEDED(rv)) {
                return rv;
            }

            nsProtocolInfo pac;
            rv = GetProtocolInfo(pacURI, &pac);
            if(!NS_SUCCEEDED(rv)) {
                return rv;
            }

            if (!pac.scheme.EqualsLiteral("file") &&
                !pac.scheme.EqualsLiteral("data")) {
                LOG((": received network changed event, reload PAC"));
                ReloadPAC();
            }
        }
    } else if ((type == PROXYCONFIG_WPAD) || (type == PROXYCONFIG_SYSTEM)) {
        ReloadPAC();
    }

    return NS_OK;
}


NS_IMETHODIMP
nsProtocolProxyService::Observe(nsISupports     *aSubject,
                                const char      *aTopic,
                                const char16_t *aData)
{
    if (strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID) == 0) {
        // cleanup
        if (mHostFiltersArray.Length() > 0) {
            mHostFiltersArray.Clear();
        }
        if (mFilters) {
            delete mFilters;
            mFilters = nullptr;
        }
        if (mPACMan) {
            mPACMan->Shutdown();
            mPACMan = nullptr;
        }

        nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
        if (obs) {
            obs->RemoveObserver(this, NS_NETWORK_LINK_TOPIC);
            obs->RemoveObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID);
        }

    } else if (strcmp(aTopic, NS_NETWORK_LINK_TOPIC) == 0) {
        nsCString converted = NS_ConvertUTF16toUTF8(aData);
        const char *state = converted.get();
        if (!strcmp(state, NS_NETWORK_LINK_DATA_CHANGED)) {
            ReloadNetworkPAC();
        }
    }
    else {
        NS_ASSERTION(strcmp(aTopic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID) == 0,
                     "what is this random observer event?");
        nsCOMPtr<nsIPrefBranch> prefs = do_QueryInterface(aSubject);
        if (prefs)
            PrefsChanged(prefs, NS_LossyConvertUTF16toASCII(aData).get());
    }
    return NS_OK;
}

void
nsProtocolProxyService::PrefsChanged(nsIPrefBranch *prefBranch,
                                     const char    *pref)
{
    nsresult rv = NS_OK;
    bool reloadPAC = false;
    nsXPIDLCString tempString;

    if (!pref || !strcmp(pref, PROXY_PREF("type"))) {
        int32_t type = -1;
        rv = prefBranch->GetIntPref(PROXY_PREF("type"), &type);
        if (NS_SUCCEEDED(rv)) {
            // bug 115720 - for ns4.x backwards compatibility
            if (type == PROXYCONFIG_DIRECT4X) {
                type = PROXYCONFIG_DIRECT;
                // Reset the type so that the dialog looks correct, and we
                // don't have to handle this case everywhere else
                // I'm paranoid about a loop of some sort - only do this
                // if we're enumerating all prefs, and ignore any error
                if (!pref)
                    prefBranch->SetIntPref(PROXY_PREF("type"), type);
            } else if (type >= PROXYCONFIG_COUNT) {
                LOG(("unknown proxy type: %lu; assuming direct\n", type));
                type = PROXYCONFIG_DIRECT;
            }
            mProxyConfig = type;
            reloadPAC = true;
        }

        if (mProxyConfig == PROXYCONFIG_SYSTEM) {
            mSystemProxySettings = do_GetService(NS_SYSTEMPROXYSETTINGS_CONTRACTID);
            if (!mSystemProxySettings)
                mProxyConfig = PROXYCONFIG_DIRECT;
            ResetPACThread();
        } else {
            if (mSystemProxySettings) {
                mSystemProxySettings = nullptr;
                ResetPACThread();
            }
        }
    }

    if (!pref || !strcmp(pref, PROXY_PREF("http")))
        proxy_GetStringPref(prefBranch, PROXY_PREF("http"), mHTTPProxyHost);

    if (!pref || !strcmp(pref, PROXY_PREF("http_port")))
        proxy_GetIntPref(prefBranch, PROXY_PREF("http_port"), mHTTPProxyPort);

    if (!pref || !strcmp(pref, PROXY_PREF("ssl")))
        proxy_GetStringPref(prefBranch, PROXY_PREF("ssl"), mHTTPSProxyHost);

    if (!pref || !strcmp(pref, PROXY_PREF("ssl_port")))
        proxy_GetIntPref(prefBranch, PROXY_PREF("ssl_port"), mHTTPSProxyPort);

    if (!pref || !strcmp(pref, PROXY_PREF("ftp")))
        proxy_GetStringPref(prefBranch, PROXY_PREF("ftp"), mFTPProxyHost);

    if (!pref || !strcmp(pref, PROXY_PREF("ftp_port")))
        proxy_GetIntPref(prefBranch, PROXY_PREF("ftp_port"), mFTPProxyPort);

    if (!pref || !strcmp(pref, PROXY_PREF("socks")))
        proxy_GetStringPref(prefBranch, PROXY_PREF("socks"), mSOCKSProxyHost);

    if (!pref || !strcmp(pref, PROXY_PREF("socks_port")))
        proxy_GetIntPref(prefBranch, PROXY_PREF("socks_port"), mSOCKSProxyPort);

    if (!pref || !strcmp(pref, PROXY_PREF("socks_version"))) {
        int32_t version;
        proxy_GetIntPref(prefBranch, PROXY_PREF("socks_version"), version);
        // make sure this preference value remains sane
        if (version == 5)
            mSOCKSProxyVersion = 5;
        else
            mSOCKSProxyVersion = 4;
    }

    if (!pref || !strcmp(pref, PROXY_PREF("socks_remote_dns")))
        proxy_GetBoolPref(prefBranch, PROXY_PREF("socks_remote_dns"),
                          mSOCKSProxyRemoteDNS);

    if (!pref || !strcmp(pref, PROXY_PREF("proxy_over_tls"))) {
        proxy_GetBoolPref(prefBranch, PROXY_PREF("proxy_over_tls"),
                          mProxyOverTLS);
    }

    if (!pref || !strcmp(pref, PROXY_PREF("failover_timeout")))
        proxy_GetIntPref(prefBranch, PROXY_PREF("failover_timeout"),
                         mFailedProxyTimeout);

    if (!pref || !strcmp(pref, PROXY_PREF("no_proxies_on"))) {
        rv = prefBranch->GetCharPref(PROXY_PREF("no_proxies_on"),
                                     getter_Copies(tempString));
        if (NS_SUCCEEDED(rv))
            LoadHostFilters(tempString.get());
    }

    // We're done if not using something that could give us a PAC URL
    // (PAC, WPAD or System)
    if (mProxyConfig != PROXYCONFIG_PAC && mProxyConfig != PROXYCONFIG_WPAD &&
        mProxyConfig != PROXYCONFIG_SYSTEM)
        return;

    // OK, we need to reload the PAC file if:
    //  1) network.proxy.type changed, or
    //  2) network.proxy.autoconfig_url changed and PAC is configured

    if (!pref || !strcmp(pref, PROXY_PREF("autoconfig_url")))
        reloadPAC = true;

    if (reloadPAC) {
        tempString.Truncate();
        if (mProxyConfig == PROXYCONFIG_PAC) {
            prefBranch->GetCharPref(PROXY_PREF("autoconfig_url"),
                                    getter_Copies(tempString));
            if (mPACMan && !mPACMan->IsPACURI(tempString)) {
                LOG(("PAC Thread URI Changed - Reset Pac Thread"));
                ResetPACThread();
            }
        } else if (mProxyConfig == PROXYCONFIG_WPAD) {
            // We diverge from the WPAD spec here in that we don't walk the
            // hosts's FQDN, stripping components until we hit a TLD.  Doing so
            // is dangerous in the face of an incomplete list of TLDs, and TLDs
            // get added over time.  We could consider doing only a single
            // substitution of the first component, if that proves to help
            // compatibility.
            tempString.AssignLiteral(WPAD_URL);
        } else if (mSystemProxySettings) {
            // Get System Proxy settings if available
            mSystemProxySettings->GetPACURI(tempString);
        }
        if (!tempString.IsEmpty())
            ConfigureFromPAC(tempString, false);
    }
}

bool
nsProtocolProxyService::CanUseProxy(nsIURI *aURI, int32_t defaultPort)
{
    if (mHostFiltersArray.Length() == 0)
        return true;

    int32_t port;
    nsAutoCString host;

    nsresult rv = aURI->GetAsciiHost(host);
    if (NS_FAILED(rv) || host.IsEmpty())
        return false;

    rv = aURI->GetPort(&port);
    if (NS_FAILED(rv))
        return false;
    if (port == -1)
        port = defaultPort;

    PRNetAddr addr;
    bool is_ipaddr = (PR_StringToNetAddr(host.get(), &addr) == PR_SUCCESS);

    PRIPv6Addr ipv6;
    if (is_ipaddr) {
        // convert parsed address to IPv6
        if (addr.raw.family == PR_AF_INET) {
            // convert to IPv4-mapped address
            PR_ConvertIPv4AddrToIPv6(addr.inet.ip, &ipv6);
        }
        else if (addr.raw.family == PR_AF_INET6) {
            // copy the address
            memcpy(&ipv6, &addr.ipv6.ip, sizeof(PRIPv6Addr));
        }
        else {
            NS_WARNING("unknown address family");
            return true; // allow proxying
        }
    }

    // Don't use proxy for local hosts (plain hostname, no dots)
    if (!is_ipaddr && mFilterLocalHosts && (kNotFound == host.FindChar('.'))) {
        LOG(("Not using proxy for this local host [%s]!\n", host.get()));
        return false; // don't allow proxying
    }

    int32_t index = -1;
    while (++index < int32_t(mHostFiltersArray.Length())) {
        HostInfo *hinfo = mHostFiltersArray[index];

        if (is_ipaddr != hinfo->is_ipaddr)
            continue;
        if (hinfo->port && hinfo->port != port)
            continue;

        if (is_ipaddr) {
            // generate masked version of target IPv6 address
            PRIPv6Addr masked;
            memcpy(&masked, &ipv6, sizeof(PRIPv6Addr));
            proxy_MaskIPv6Addr(masked, hinfo->ip.mask_len);

            // check for a match
            if (memcmp(&masked, &hinfo->ip.addr, sizeof(PRIPv6Addr)) == 0)
                return false; // proxy disallowed
        }
        else {
            uint32_t host_len = host.Length();
            uint32_t filter_host_len = hinfo->name.host_len;

            if (host_len >= filter_host_len) {
                //
                // compare last |filter_host_len| bytes of target hostname.
                //
                const char *host_tail = host.get() + host_len - filter_host_len;
                if (!PL_strncasecmp(host_tail, hinfo->name.host, filter_host_len))
                    return false; // proxy disallowed
            }
        }
    }
    return true;
}

// kProxyType\* may be referred to externally in
// nsProxyInfo in order to compare by string pointer
namespace mozilla {
const char kProxyType_HTTP[]    = "http";
const char kProxyType_HTTPS[]   = "https";
const char kProxyType_PROXY[]   = "proxy";
const char kProxyType_SOCKS[]   = "socks";
const char kProxyType_SOCKS4[]  = "socks4";
const char kProxyType_SOCKS5[]  = "socks5";
const char kProxyType_DIRECT[]  = "direct";
}

const char *
nsProtocolProxyService::ExtractProxyInfo(const char *start,
                                         uint32_t aResolveFlags,
                                         nsProxyInfo **result)
{
    *result = nullptr;
    uint32_t flags = 0;

    // see BNF in ProxyAutoConfig.h and notes in nsISystemProxySettings.idl

    // find end of proxy info delimiter
    const char *end = start;
    while (*end && *end != ';') ++end;

    // find end of proxy type delimiter
    const char *sp = start;
    while (sp < end && *sp != ' ' && *sp != '\t') ++sp;

    uint32_t len = sp - start;
    const char *type = nullptr;
    switch (len) {
    case 4:
        if (PL_strncasecmp(start, kProxyType_HTTP, 5) == 0) {
            type = kProxyType_HTTP;
        }
        break;
    case 5:
        if (PL_strncasecmp(start, kProxyType_PROXY, 5) == 0) {
            type = kProxyType_HTTP;
        } else if (PL_strncasecmp(start, kProxyType_SOCKS, 5) == 0) {
            type = kProxyType_SOCKS4; // assume v4 for 4x compat
        } else if (PL_strncasecmp(start, kProxyType_HTTPS, 5) == 0) {
            type = kProxyType_HTTPS;
        }
        break;
    case 6:
        if (PL_strncasecmp(start, kProxyType_DIRECT, 6) == 0)
            type = kProxyType_DIRECT;
        else if (PL_strncasecmp(start, kProxyType_SOCKS4, 6) == 0)
            type = kProxyType_SOCKS4;
        else if (PL_strncasecmp(start, kProxyType_SOCKS5, 6) == 0)
            // map "SOCKS5" to "socks" to match contract-id of registered
            // SOCKS-v5 socket provider.
            type = kProxyType_SOCKS;
        break;
    }
    if (type) {
        const char *host = nullptr, *hostEnd = nullptr;
        int32_t port = -1;

        // If it's a SOCKS5 proxy, do name resolution on the server side.
        // We could use this with SOCKS4a servers too, but they might not
        // support it.
        if (type == kProxyType_SOCKS || mSOCKSProxyRemoteDNS)
            flags |= nsIProxyInfo::TRANSPARENT_PROXY_RESOLVES_HOST;

        // extract host:port
        start = sp;
        while ((*start == ' ' || *start == '\t') && start < end)
            start++;

        // port defaults
        if (type == kProxyType_HTTP) {
            port = 80;
        } else if (type == kProxyType_HTTPS) {
            port = 443;
        } else {
            port = 1080;
        }

        nsProxyInfo *pi = new nsProxyInfo();
        pi->mType = type;
        pi->mFlags = flags;
        pi->mResolveFlags = aResolveFlags;
        pi->mTimeout = mFailedProxyTimeout;

        // www.foo.com:8080 and http://www.foo.com:8080
        nsDependentCSubstring maybeURL(start, end - start);
        nsCOMPtr<nsIURI> pacURI;

        nsAutoCString urlHost;
        if (NS_SUCCEEDED(NS_NewURI(getter_AddRefs(pacURI), maybeURL)) &&
            NS_SUCCEEDED(pacURI->GetAsciiHost(urlHost)) &&
            !urlHost.IsEmpty()) {
            // http://www.example.com:8080

            pi->mHost = urlHost;

            int32_t tPort;
            if (NS_SUCCEEDED(pacURI->GetPort(&tPort)) && tPort != -1) {
                port = tPort;
            }
            pi->mPort = port;
        }
        else {
            // www.example.com:8080
            if (start < end) {
                host = start;
                hostEnd = strchr(host, ':');
                if (!hostEnd || hostEnd > end) {
                    hostEnd = end;
                    // no port, so assume default
                }
                else {
                    port = atoi(hostEnd + 1);
                }
            }
            // YES, it is ok to specify a null proxy host.
            if (host) {
                pi->mHost.Assign(host, hostEnd - host);
                pi->mPort = port;
            }
        }
        NS_ADDREF(*result = pi);
    }

    while (*end == ';' || *end == ' ' || *end == '\t')
        ++end;
    return end;
}

void
nsProtocolProxyService::GetProxyKey(nsProxyInfo *pi, nsCString &key)
{
    key.AssignASCII(pi->mType);
    if (!pi->mHost.IsEmpty()) {
        key.Append(' ');
        key.Append(pi->mHost);
        key.Append(':');
        key.AppendInt(pi->mPort);
    }
}

uint32_t
nsProtocolProxyService::SecondsSinceSessionStart()
{
    PRTime now = PR_Now();

    // get time elapsed since session start
    int64_t diff = now - mSessionStart;

    // convert microseconds to seconds
    diff /= PR_USEC_PER_SEC;

    // return converted 32 bit value
    return uint32_t(diff);
}

void
nsProtocolProxyService::EnableProxy(nsProxyInfo *pi)
{
    nsAutoCString key;
    GetProxyKey(pi, key);
    mFailedProxies.Remove(key);
}

void
nsProtocolProxyService::DisableProxy(nsProxyInfo *pi)
{
    nsAutoCString key;
    GetProxyKey(pi, key);

    uint32_t dsec = SecondsSinceSessionStart();

    // Add timeout to interval (this is the time when the proxy can
    // be tried again).
    dsec += pi->mTimeout;

    // NOTE: The classic codebase would increase the timeout value
    //       incrementally each time a subsequent failure occurred.
    //       We could do the same, but it would require that we not
    //       remove proxy entries in IsProxyDisabled or otherwise
    //       change the way we are recording disabled proxies.
    //       Simpler is probably better for now, and at least the
    //       user can tune the timeout setting via preferences.

    LOG(("DisableProxy %s %d\n", key.get(), dsec));

    // If this fails, oh well... means we don't have enough memory
    // to remember the failed proxy.
    mFailedProxies.Put(key, dsec);
}

bool
nsProtocolProxyService::IsProxyDisabled(nsProxyInfo *pi)
{
    nsAutoCString key;
    GetProxyKey(pi, key);

    uint32_t val;
    if (!mFailedProxies.Get(key, &val))
        return false;

    uint32_t dsec = SecondsSinceSessionStart();

    // if time passed has exceeded interval, then try proxy again.
    if (dsec > val) {
        mFailedProxies.Remove(key);
        return false;
    }

    return true;
}

nsresult
nsProtocolProxyService::SetupPACThread()
{
    if (mPACMan)
        return NS_OK;

    mPACMan = new nsPACMan();

    bool mainThreadOnly;
    nsresult rv;
    if (mSystemProxySettings &&
        NS_SUCCEEDED(mSystemProxySettings->GetMainThreadOnly(&mainThreadOnly)) &&
        !mainThreadOnly) {
        rv = mPACMan->Init(mSystemProxySettings);
    }
    else {
        rv = mPACMan->Init(nullptr);
    }

    if (NS_FAILED(rv))
        mPACMan = nullptr;
    return rv;
}

nsresult
nsProtocolProxyService::ResetPACThread()
{
    if (!mPACMan)
        return NS_OK;

    mPACMan->Shutdown();
    mPACMan = nullptr;
    return SetupPACThread();
}

nsresult
nsProtocolProxyService::ConfigureFromPAC(const nsCString &spec,
                                         bool forceReload)
{
    SetupPACThread();

    if (mPACMan->IsPACURI(spec) && !forceReload)
        return NS_OK;

    mFailedProxies.Clear();

    return mPACMan->LoadPACFromURI(spec);
}

void
nsProtocolProxyService::ProcessPACString(const nsCString &pacString,
                                         uint32_t aResolveFlags,
                                         nsIProxyInfo **result)
{
    if (pacString.IsEmpty()) {
        *result = nullptr;
        return;
    }

    const char *proxies = pacString.get();

    nsProxyInfo *pi = nullptr, *first = nullptr, *last = nullptr;
    while (*proxies) {
        proxies = ExtractProxyInfo(proxies, aResolveFlags, &pi);
        if (pi && (pi->mType == kProxyType_HTTPS) && !mProxyOverTLS) {
            delete pi;
            pi = nullptr;
        }

        if (pi) {
            if (last) {
                NS_ASSERTION(last->mNext == nullptr, "leaking nsProxyInfo");
                last->mNext = pi;
            }
            else
                first = pi;
            last = pi;
        }
    }
    *result = first;
}

// nsIProtocolProxyService2
NS_IMETHODIMP
nsProtocolProxyService::ReloadPAC()
{
    nsCOMPtr<nsIPrefBranch> prefs = do_GetService(NS_PREFSERVICE_CONTRACTID);
    if (!prefs)
        return NS_OK;

    int32_t type;
    nsresult rv = prefs->GetIntPref(PROXY_PREF("type"), &type);
    if (NS_FAILED(rv))
        return NS_OK;

    nsXPIDLCString pacSpec;
    if (type == PROXYCONFIG_PAC)
        prefs->GetCharPref(PROXY_PREF("autoconfig_url"), getter_Copies(pacSpec));
    else if (type == PROXYCONFIG_WPAD)
        pacSpec.AssignLiteral(WPAD_URL);

    if (!pacSpec.IsEmpty())
        ConfigureFromPAC(pacSpec, true);
    return NS_OK;
}

// When sync interface is removed this can go away too
// The nsPACManCallback portion of this implementation should be run
// off the main thread, because it uses a condvar for signaling and
// the main thread is blocking on that condvar -
//  so call nsPACMan::AsyncGetProxyForURI() with
// a false mainThreadResponse parameter.
class nsAsyncBridgeRequest final  : public nsPACManCallback
{
    NS_DECL_THREADSAFE_ISUPPORTS

     nsAsyncBridgeRequest()
        : mMutex("nsDeprecatedCallback")
        , mCondVar(mMutex, "nsDeprecatedCallback")
        , mCompleted(false)
    {
    }

    void OnQueryComplete(nsresult status,
                         const nsCString &pacString,
                         const nsCString &newPACURL) override
    {
        MutexAutoLock lock(mMutex);
        mCompleted = true;
        mStatus = status;
        mPACString = pacString;
        mPACURL = newPACURL;
        mCondVar.Notify();
    }

    void Lock()   { mMutex.Lock(); }
    void Unlock() { mMutex.Unlock(); }
    void Wait()   { mCondVar.Wait(PR_SecondsToInterval(3)); }

private:
    ~nsAsyncBridgeRequest()
    {
    }

    friend class nsProtocolProxyService;

    Mutex    mMutex;
    CondVar  mCondVar;

    nsresult  mStatus;
    nsCString mPACString;
    nsCString mPACURL;
    bool      mCompleted;
};
NS_IMPL_ISUPPORTS0(nsAsyncBridgeRequest)

// nsProtocolProxyService
nsresult
nsProtocolProxyService::DeprecatedBlockingResolve(nsIChannel *aChannel,
                                                  uint32_t aFlags,
                                                  nsIProxyInfo **retval)
{
    NS_ENSURE_ARG_POINTER(aChannel);

    nsCOMPtr<nsIURI> uri;
    nsresult rv = GetProxyURI(aChannel, getter_AddRefs(uri));
    if (NS_FAILED(rv)) return rv;

    nsProtocolInfo info;
    rv = GetProtocolInfo(uri, &info);
    if (NS_FAILED(rv))
        return rv;

    nsCOMPtr<nsIProxyInfo> pi;
    bool usePACThread;

    // SystemProxySettings and PAC files can block the main thread
    // but if neither of them are in use, we can just do the work
    // right here and directly invoke the callback

    rv = Resolve_Internal(aChannel, NECKO_NO_APP_ID, false, info, aFlags,
                          &usePACThread, getter_AddRefs(pi));
    if (NS_FAILED(rv))
        return rv;

    if (!usePACThread || !mPACMan) {
        ApplyFilters(aChannel, info, pi);
        pi.forget(retval);
        return NS_OK;
    }

    // Use the PAC thread to do the work, so we don't have to reimplement that
    // code, but block this thread on that completion.
    nsRefPtr<nsAsyncBridgeRequest> ctx = new nsAsyncBridgeRequest();
    ctx->Lock();
    if (NS_SUCCEEDED(mPACMan->AsyncGetProxyForURI(uri, NECKO_NO_APP_ID, false,
                                                  ctx, false))) {
        // this can really block the main thread, so cap it at 3 seconds
       ctx->Wait();
    }
    ctx->Unlock();
    if (!ctx->mCompleted)
        return NS_ERROR_FAILURE;
    if (NS_FAILED(ctx->mStatus))
        return ctx->mStatus;

    // pretty much duplicate real DoCallback logic

    // Generate proxy info from the PAC string if appropriate
    if (!ctx->mPACString.IsEmpty()) {
        LOG(("sync pac thread callback %s\n", ctx->mPACString.get()));
        ProcessPACString(ctx->mPACString, 0, getter_AddRefs(pi));
        ApplyFilters(aChannel, info, pi);
        pi.forget(retval);
        return NS_OK;
    }

    if (!ctx->mPACURL.IsEmpty()) {
        NS_WARNING("sync pac thread callback indicates new pac file load\n");
        // This is a problem and is one of the reasons this blocking interface
        // is deprecated. The main loop needs to spin to make this reload happen. So
        // we are going to kick off the reload and return an error - it will work
        // next time. Because this sync interface is only used in the java plugin it
        // is extremely likely that the pac file has already been loaded anyhow.

        rv = ConfigureFromPAC(ctx->mPACURL, false);
        if (NS_FAILED(rv))
            return rv;
        return NS_ERROR_NOT_AVAILABLE;
    }

    *retval = nullptr;
    return NS_OK;
}

nsresult
nsProtocolProxyService::AsyncResolveInternal(nsIChannel *channel, uint32_t flags,
                                             nsIProtocolProxyCallback *callback,
                                             nsICancelable **result,
                                             bool isSyncOK)
{
    NS_ENSURE_ARG_POINTER(channel);
    NS_ENSURE_ARG_POINTER(callback);

    nsCOMPtr<nsIURI> uri;
    nsresult rv = GetProxyURI(channel, getter_AddRefs(uri));
    if (NS_FAILED(rv)) return rv;

    uint32_t appId = NECKO_NO_APP_ID;
    bool isInBrowser = false;
    NS_GetAppInfo(channel, &appId, &isInBrowser);

    *result = nullptr;
    nsRefPtr<nsAsyncResolveRequest> ctx =
        new nsAsyncResolveRequest(this, channel, appId, isInBrowser, flags,
                                  callback);

    nsProtocolInfo info;
    rv = GetProtocolInfo(uri, &info);
    if (NS_FAILED(rv))
        return rv;

    nsCOMPtr<nsIProxyInfo> pi;
    bool usePACThread;

    // SystemProxySettings and PAC files can block the main thread
    // but if neither of them are in use, we can just do the work
    // right here and directly invoke the callback

    rv = Resolve_Internal(channel, appId, isInBrowser, info, flags,
                          &usePACThread, getter_AddRefs(pi));
    if (NS_FAILED(rv))
        return rv;

    if (!usePACThread || !mPACMan) {
        // we can do it locally
        ApplyFilters(channel, info, pi);
        ctx->SetResult(NS_OK, pi);
        if (isSyncOK) {
            ctx->Run();
            return NS_OK;
        }

        rv = ctx->DispatchCallback();
        if (NS_SUCCEEDED(rv))
            ctx.forget(result);
        return rv;
    }

    // else kick off a PAC thread query

    rv = mPACMan->AsyncGetProxyForURI(uri, appId, isInBrowser, ctx, true);
    if (NS_SUCCEEDED(rv))
        ctx.forget(result);
    return rv;
}

// nsIProtocolProxyService
NS_IMETHODIMP
nsProtocolProxyService::AsyncResolve2(nsIChannel *channel, uint32_t flags,
                                      nsIProtocolProxyCallback *callback,
                                      nsICancelable **result)
{
    return AsyncResolveInternal(channel, flags, callback, result, true);
}

NS_IMETHODIMP
nsProtocolProxyService::AsyncResolve(nsISupports *channelOrURI, uint32_t flags,
                                     nsIProtocolProxyCallback *callback,
                                     nsICancelable **result)
{

    nsresult rv;
    // Check if we got a channel:
    nsCOMPtr<nsIChannel> channel = do_QueryInterface(channelOrURI);
    if (!channel) {
        nsCOMPtr<nsIURI> uri = do_QueryInterface(channelOrURI);
        if (!uri) {
            return NS_ERROR_NO_INTERFACE;
        }

        nsCOMPtr<nsIScriptSecurityManager> secMan(
            do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv));
        NS_ENSURE_SUCCESS(rv, rv);
        nsCOMPtr<nsIPrincipal> systemPrincipal;
        rv = secMan->GetSystemPrincipal(getter_AddRefs(systemPrincipal));
        NS_ENSURE_SUCCESS(rv, rv);

        // creating a temporary channel from the URI which is not
        // used to perform any network loads, hence its safe to
        // use systemPrincipal as the loadingPrincipal.
        rv = NS_NewChannel(getter_AddRefs(channel),
                           uri,
                           systemPrincipal,
                           nsILoadInfo::SEC_NORMAL,
                           nsIContentPolicy::TYPE_OTHER);
        NS_ENSURE_SUCCESS(rv, rv);
    }

    return AsyncResolveInternal(channel, flags, callback, result, false);
}

NS_IMETHODIMP
nsProtocolProxyService::NewProxyInfo(const nsACString &aType,
                                     const nsACString &aHost,
                                     int32_t aPort,
                                     uint32_t aFlags,
                                     uint32_t aFailoverTimeout,
                                     nsIProxyInfo *aFailoverProxy,
                                     nsIProxyInfo **aResult)
{
    static const char *types[] = {
        kProxyType_HTTP,
        kProxyType_HTTPS,
        kProxyType_SOCKS,
        kProxyType_SOCKS4,
        kProxyType_DIRECT
    };

    // resolve type; this allows us to avoid copying the type string into each
    // proxy info instance.  we just reference the string literals directly :)
    const char *type = nullptr;
    for (uint32_t i = 0; i < ArrayLength(types); ++i) {
        if (aType.LowerCaseEqualsASCII(types[i])) {
            type = types[i];
            break;
        }
    }
    NS_ENSURE_TRUE(type, NS_ERROR_INVALID_ARG);

    if (aPort <= 0)
        aPort = -1;

    return NewProxyInfo_Internal(type, aHost, aPort, aFlags, aFailoverTimeout,
                                 aFailoverProxy, 0, aResult);
}

NS_IMETHODIMP
nsProtocolProxyService::GetFailoverForProxy(nsIProxyInfo  *aProxy,
                                            nsIURI        *aURI,
                                            nsresult       aStatus,
                                            nsIProxyInfo **aResult)
{
    // We only support failover when a PAC file is configured, either
    // directly or via system settings
    if (mProxyConfig != PROXYCONFIG_PAC && mProxyConfig != PROXYCONFIG_WPAD &&
        mProxyConfig != PROXYCONFIG_SYSTEM)
        return NS_ERROR_NOT_AVAILABLE;

    // Verify that |aProxy| is one of our nsProxyInfo objects.
    nsCOMPtr<nsProxyInfo> pi = do_QueryInterface(aProxy);
    NS_ENSURE_ARG(pi);
    // OK, the QI checked out.  We can proceed.

    // Remember that this proxy is down.
    DisableProxy(pi);

    // NOTE: At this point, we might want to prompt the user if we have
    //       not already tried going DIRECT.  This is something that the
    //       classic codebase supported; however, IE6 does not prompt.

    if (!pi->mNext)
        return NS_ERROR_NOT_AVAILABLE;

    LOG(("PAC failover from %s %s:%d to %s %s:%d\n",
        pi->mType, pi->mHost.get(), pi->mPort,
        pi->mNext->mType, pi->mNext->mHost.get(), pi->mNext->mPort));

    NS_ADDREF(*aResult = pi->mNext);
    return NS_OK;
}

nsresult
nsProtocolProxyService::InsertFilterLink(FilterLink *link, uint32_t position)
{
    if (!mFilters) {
        mFilters = link;
        return NS_OK;
    }

    // insert into mFilters in sorted order
    FilterLink *last = nullptr;
    for (FilterLink *iter = mFilters; iter; iter = iter->next) {
        if (position < iter->position) {
            if (last) {
                link->next = last->next;
                last->next = link;
            }
            else {
                link->next = mFilters;
                mFilters = link;
            }
            return NS_OK;
        }
        last = iter;
    }
    // our position is equal to or greater than the last link in the list
    last->next = link;
    return NS_OK;
}

NS_IMETHODIMP
nsProtocolProxyService::RegisterFilter(nsIProtocolProxyFilter *filter,
                                       uint32_t position)
{
    UnregisterFilter(filter); // remove this filter if we already have it

    FilterLink *link = new FilterLink(position, filter);
    if (!link) {
        return NS_ERROR_OUT_OF_MEMORY;
    }
    return InsertFilterLink(link, position);
}

NS_IMETHODIMP
nsProtocolProxyService::RegisterChannelFilter(nsIProtocolProxyChannelFilter *channelFilter,
                                              uint32_t position)
{
    UnregisterChannelFilter(channelFilter);  // remove this filter if we already have it

    FilterLink *link = new FilterLink(position, channelFilter);
    if (!link) {
        return NS_ERROR_OUT_OF_MEMORY;
    }
    return InsertFilterLink(link, position);
}

nsresult
nsProtocolProxyService::RemoveFilterLink(nsISupports* givenObject)
{
    FilterLink *last = nullptr;
    for (FilterLink *iter = mFilters; iter; iter = iter->next) {
        nsCOMPtr<nsISupports> object = do_QueryInterface(iter->filter);
        nsCOMPtr<nsISupports> object2 = do_QueryInterface(iter->channelFilter);
        if (object == givenObject || object2 == givenObject) {
            if (last)
                last->next = iter->next;
            else
                mFilters = iter->next;
            iter->next = nullptr;
            delete iter;
            return NS_OK;
        }
        last = iter;
    }

    // No need to throw an exception in this case.
    return NS_OK;
}

NS_IMETHODIMP
nsProtocolProxyService::UnregisterFilter(nsIProtocolProxyFilter *filter) {
    // QI to nsISupports so we can safely test object identity.
    nsCOMPtr<nsISupports> givenObject = do_QueryInterface(filter);
    return RemoveFilterLink(givenObject);
}

NS_IMETHODIMP
nsProtocolProxyService::UnregisterChannelFilter(nsIProtocolProxyChannelFilter *channelFilter) {
    // QI to nsISupports so we can safely test object identity.
    nsCOMPtr<nsISupports> givenObject = do_QueryInterface(channelFilter);
    return RemoveFilterLink(givenObject);
}

NS_IMETHODIMP
nsProtocolProxyService::GetProxyConfigType(uint32_t* aProxyConfigType)
{
  *aProxyConfigType = mProxyConfig;
  return NS_OK;
}

void
nsProtocolProxyService::LoadHostFilters(const char *filters)
{
    // check to see the owners flag? /!?/ TODO
    if (mHostFiltersArray.Length() > 0) {
        mHostFiltersArray.Clear();
    }

    if (!filters)
        return; // fail silently...

    //
    // filter  = ( host | domain | ipaddr ["/" mask] ) [":" port]
    // filters = filter *( "," LWS filter)
    //
    // Reset mFilterLocalHosts - will be set to true if "<local>" is in pref string
    mFilterLocalHosts = false;
    while (*filters) {
        // skip over spaces and ,
        while (*filters && (*filters == ',' || IS_ASCII_SPACE(*filters)))
            filters++;

        const char *starthost = filters;
        const char *endhost = filters + 1; // at least that...
        const char *portLocation = 0;
        const char *maskLocation = 0;

        while (*endhost && (*endhost != ',' && !IS_ASCII_SPACE(*endhost))) {
            if (*endhost == ':')
                portLocation = endhost;
            else if (*endhost == '/')
                maskLocation = endhost;
            else if (*endhost == ']') // IPv6 address literals
                portLocation = 0;
            endhost++;
        }

        filters = endhost; // advance iterator up front

        // locate end of host
        const char *end = maskLocation ? maskLocation :
                          portLocation ? portLocation :
                          endhost;

        nsAutoCString str(starthost, end - starthost);

        // If the current host filter is "<local>", then all local (i.e.
        // no dots in the hostname) hosts should bypass the proxy
        if (str.EqualsIgnoreCase("<local>")) {
            mFilterLocalHosts = true;
            LOG(("loaded filter for local hosts "
                 "(plain host names, no dots)\n"));
            // Continue to next host filter;
            continue;
        }

        // For all other host filters, create HostInfo object and add to list
        HostInfo *hinfo = new HostInfo();
        hinfo->port = portLocation ? atoi(portLocation + 1) : 0;

        PRNetAddr addr;
        if (PR_StringToNetAddr(str.get(), &addr) == PR_SUCCESS) {
            hinfo->is_ipaddr   = true;
            hinfo->ip.family   = PR_AF_INET6; // we always store address as IPv6
            hinfo->ip.mask_len = maskLocation ? atoi(maskLocation + 1) : 128;

            if (hinfo->ip.mask_len == 0) {
                NS_WARNING("invalid mask");
                goto loser;
            }

            if (addr.raw.family == PR_AF_INET) {
                // convert to IPv4-mapped address
                PR_ConvertIPv4AddrToIPv6(addr.inet.ip, &hinfo->ip.addr);
                // adjust mask_len accordingly
                if (hinfo->ip.mask_len <= 32)
                    hinfo->ip.mask_len += 96;
            }
            else if (addr.raw.family == PR_AF_INET6) {
                // copy the address
                memcpy(&hinfo->ip.addr, &addr.ipv6.ip, sizeof(PRIPv6Addr));
            }
            else {
                NS_WARNING("unknown address family");
                goto loser;
            }

            // apply mask to IPv6 address
            proxy_MaskIPv6Addr(hinfo->ip.addr, hinfo->ip.mask_len);
        }
        else {
            uint32_t startIndex, endIndex;
            if (str.First() == '*')
                startIndex = 1; // *.domain -> .domain
            else
                startIndex = 0;
            endIndex = (portLocation ? portLocation : endhost) - starthost;

            hinfo->is_ipaddr = false;
            hinfo->name.host = ToNewCString(Substring(str, startIndex, endIndex));

            if (!hinfo->name.host)
                goto loser;

            hinfo->name.host_len = endIndex - startIndex;
        }

//#define DEBUG_DUMP_FILTERS
#ifdef DEBUG_DUMP_FILTERS
        printf("loaded filter[%u]:\n", mHostFiltersArray.Length());
        printf("  is_ipaddr = %u\n", hinfo->is_ipaddr);
        printf("  port = %u\n", hinfo->port);
        if (hinfo->is_ipaddr) {
            printf("  ip.family = %x\n", hinfo->ip.family);
            printf("  ip.mask_len = %u\n", hinfo->ip.mask_len);

            PRNetAddr netAddr;
            PR_SetNetAddr(PR_IpAddrNull, PR_AF_INET6, 0, &netAddr);
            memcpy(&netAddr.ipv6.ip, &hinfo->ip.addr, sizeof(hinfo->ip.addr));

            char buf[256];
            PR_NetAddrToString(&netAddr, buf, sizeof(buf));

            printf("  ip.addr = %s\n", buf);
        }
        else {
            printf("  name.host = %s\n", hinfo->name.host);
        }
#endif

        mHostFiltersArray.AppendElement(hinfo);
        hinfo = nullptr;
loser:
        delete hinfo;
    }
}

nsresult
nsProtocolProxyService::GetProtocolInfo(nsIURI *uri, nsProtocolInfo *info)
{
    NS_PRECONDITION(uri, "URI is null");
    NS_PRECONDITION(info, "info is null");

    nsresult rv;

    rv = uri->GetScheme(info->scheme);
    if (NS_FAILED(rv))
        return rv;

    nsCOMPtr<nsIIOService> ios = do_GetIOService(&rv);
    if (NS_FAILED(rv))
        return rv;

    nsCOMPtr<nsIProtocolHandler> handler;
    rv = ios->GetProtocolHandler(info->scheme.get(), getter_AddRefs(handler));
    if (NS_FAILED(rv))
        return rv;

    rv = handler->GetProtocolFlags(&info->flags);
    if (NS_FAILED(rv))
        return rv;

    rv = handler->GetDefaultPort(&info->defaultPort);
    return rv;
}

nsresult
nsProtocolProxyService::NewProxyInfo_Internal(const char *aType,
                                              const nsACString &aHost,
                                              int32_t aPort,
                                              uint32_t aFlags,
                                              uint32_t aFailoverTimeout,
                                              nsIProxyInfo *aFailoverProxy,
                                              uint32_t aResolveFlags,
                                              nsIProxyInfo **aResult)
{
    nsCOMPtr<nsProxyInfo> failover;
    if (aFailoverProxy) {
        failover = do_QueryInterface(aFailoverProxy);
        NS_ENSURE_ARG(failover);
    }

    nsProxyInfo *proxyInfo = new nsProxyInfo();
    if (!proxyInfo)
        return NS_ERROR_OUT_OF_MEMORY;

    proxyInfo->mType = aType;
    proxyInfo->mHost = aHost;
    proxyInfo->mPort = aPort;
    proxyInfo->mFlags = aFlags;
    proxyInfo->mResolveFlags = aResolveFlags;
    proxyInfo->mTimeout = aFailoverTimeout == UINT32_MAX
        ? mFailedProxyTimeout : aFailoverTimeout;
    failover.swap(proxyInfo->mNext);

    NS_ADDREF(*aResult = proxyInfo);
    return NS_OK;
}

nsresult
nsProtocolProxyService::Resolve_Internal(nsIChannel *channel,
                                         uint32_t appId,
                                         bool isInBrowser,
                                         const nsProtocolInfo &info,
                                         uint32_t flags,
                                         bool *usePACThread,
                                         nsIProxyInfo **result)
{
    NS_ENSURE_ARG_POINTER(channel);
    nsresult rv = SetupPACThread();
    if (NS_FAILED(rv))
        return rv;

    *usePACThread = false;
    *result = nullptr;

    if (!(info.flags & nsIProtocolHandler::ALLOWS_PROXY))
        return NS_OK;  // Can't proxy this (filters may not override)

    nsCOMPtr<nsIURI> uri;
    rv = GetProxyURI(channel, getter_AddRefs(uri));
    if (NS_FAILED(rv)) return rv;

    // See bug #586908.
    // Avoid endless loop if |uri| is the current PAC-URI. Returning OK
    // here means that we will not use a proxy for this connection.
    if (mPACMan && mPACMan->IsPACURI(uri))
        return NS_OK;

    bool mainThreadOnly;
    if (mSystemProxySettings &&
        mProxyConfig == PROXYCONFIG_SYSTEM &&
        NS_SUCCEEDED(mSystemProxySettings->GetMainThreadOnly(&mainThreadOnly)) &&
        !mainThreadOnly) {
        *usePACThread = true;
        return NS_OK;
    }

    if (mSystemProxySettings && mProxyConfig == PROXYCONFIG_SYSTEM) {
        // If the system proxy setting implementation is not threadsafe (e.g
        // linux gconf), we'll do it inline here. Such implementations promise
        // not to block

        nsAutoCString PACURI;
        nsAutoCString pacString;

        if (NS_SUCCEEDED(mSystemProxySettings->GetPACURI(PACURI)) &&
            !PACURI.IsEmpty()) {
            // There is a PAC URI configured. If it is unchanged, then
            // just execute the PAC thread. If it is changed then load
            // the new value

            if (mPACMan && mPACMan->IsPACURI(PACURI)) {
                // unchanged
                *usePACThread = true;
                return NS_OK;
            }

            ConfigureFromPAC(PACURI, false);
            return NS_OK;
        }

        nsAutoCString spec;
        nsAutoCString host;
        nsAutoCString scheme;
        int32_t port = -1;

        uri->GetAsciiSpec(spec);
        uri->GetAsciiHost(host);
        uri->GetScheme(scheme);
        uri->GetPort(&port);

        // now try the system proxy settings for this particular url
        if (NS_SUCCEEDED(mSystemProxySettings->
                         GetProxyForURI(spec, scheme, host, port,
                                        pacString))) {
            ProcessPACString(pacString, 0, result);
            return NS_OK;
        }
    }

    // if proxies are enabled and this host:port combo is supposed to use a
    // proxy, check for a proxy.
    if (mProxyConfig == PROXYCONFIG_DIRECT ||
        (mProxyConfig == PROXYCONFIG_MANUAL &&
         !CanUseProxy(uri, info.defaultPort)))
        return NS_OK;

    // Proxy auto config magic...
    if (mProxyConfig == PROXYCONFIG_PAC || mProxyConfig == PROXYCONFIG_WPAD) {
        // Do not query PAC now.
        *usePACThread = true;
        return NS_OK;
    }

    // If we aren't in manual proxy configuration mode then we don't
    // want to honor any manual specific prefs that might be still set
    if (mProxyConfig != PROXYCONFIG_MANUAL)
        return NS_OK;

    // proxy info values for manual configuration mode
    const char *type = nullptr;
    const nsACString *host = nullptr;
    int32_t port = -1;

    uint32_t proxyFlags = 0;

    if ((flags & RESOLVE_PREFER_SOCKS_PROXY) &&
        !mSOCKSProxyHost.IsEmpty() && mSOCKSProxyPort > 0) {
      host = &mSOCKSProxyHost;
      if (mSOCKSProxyVersion == 4)
          type = kProxyType_SOCKS4;
      else
          type = kProxyType_SOCKS;
      port = mSOCKSProxyPort;
      if (mSOCKSProxyRemoteDNS)
          proxyFlags |= nsIProxyInfo::TRANSPARENT_PROXY_RESOLVES_HOST;
    }
    else if ((flags & RESOLVE_PREFER_HTTPS_PROXY) &&
             !mHTTPSProxyHost.IsEmpty() && mHTTPSProxyPort > 0) {
        host = &mHTTPSProxyHost;
        type = kProxyType_HTTP;
        port = mHTTPSProxyPort;
    }
    else if (!mHTTPProxyHost.IsEmpty() && mHTTPProxyPort > 0 &&
             ((flags & RESOLVE_IGNORE_URI_SCHEME) ||
              info.scheme.EqualsLiteral("http"))) {
        host = &mHTTPProxyHost;
        type = kProxyType_HTTP;
        port = mHTTPProxyPort;
    }
    else if (!mHTTPSProxyHost.IsEmpty() && mHTTPSProxyPort > 0 &&
             !(flags & RESOLVE_IGNORE_URI_SCHEME) &&
             info.scheme.EqualsLiteral("https")) {
        host = &mHTTPSProxyHost;
        type = kProxyType_HTTP;
        port = mHTTPSProxyPort;
    }
    else if (!mFTPProxyHost.IsEmpty() && mFTPProxyPort > 0 &&
             !(flags & RESOLVE_IGNORE_URI_SCHEME) &&
             info.scheme.EqualsLiteral("ftp")) {
        host = &mFTPProxyHost;
        type = kProxyType_HTTP;
        port = mFTPProxyPort;
    }
    else if (!mSOCKSProxyHost.IsEmpty() && mSOCKSProxyPort > 0) {
        host = &mSOCKSProxyHost;
        if (mSOCKSProxyVersion == 4)
            type = kProxyType_SOCKS4;
        else
            type = kProxyType_SOCKS;
        port = mSOCKSProxyPort;
        if (mSOCKSProxyRemoteDNS)
            proxyFlags |= nsIProxyInfo::TRANSPARENT_PROXY_RESOLVES_HOST;
    }

    if (type) {
        rv = NewProxyInfo_Internal(type, *host, port, proxyFlags,
                                   UINT32_MAX, nullptr, flags,
                                   result);
        if (NS_FAILED(rv))
            return rv;
    }

    return NS_OK;
}

void
nsProtocolProxyService::MaybeDisableDNSPrefetch(nsIProxyInfo *aProxy)
{
    // Disable Prefetch in the DNS service if a proxy is in use.
    if (!aProxy)
        return;

    nsCOMPtr<nsProxyInfo> pi = do_QueryInterface(aProxy);
    if (!pi ||
        !pi->mType ||
        pi->mType == kProxyType_DIRECT)
        return;

    nsCOMPtr<nsIDNSService> dns = do_GetService(NS_DNSSERVICE_CONTRACTID);
    if (!dns)
        return;
    nsCOMPtr<nsPIDNSService> pdns = do_QueryInterface(dns);
    if (!pdns)
        return;

    // We lose the prefetch optimization for the life of the dns service.
    pdns->SetPrefetchEnabled(false);
}

void
nsProtocolProxyService::ApplyFilters(nsIChannel *channel,
                                     const nsProtocolInfo &info,
                                     nsIProxyInfo **list)
{
    if (!(info.flags & nsIProtocolHandler::ALLOWS_PROXY))
        return;

    // We prune the proxy list prior to invoking each filter.  This may be
    // somewhat inefficient, but it seems like a good idea since we want each
    // filter to "see" a valid proxy list.

    nsCOMPtr<nsIProxyInfo> result;

    for (FilterLink *iter = mFilters; iter; iter = iter->next) {
        PruneProxyInfo(info, list);
        nsresult rv = NS_OK;
        if (iter->filter) {
          nsCOMPtr<nsIURI> uri;
          rv = GetProxyURI(channel, getter_AddRefs(uri));
          if (uri) {
            rv = iter->filter->ApplyFilter(this, uri, *list,
                                           getter_AddRefs(result));
          }
        } else if (iter->channelFilter) {
          rv = iter->channelFilter->ApplyFilter(this, channel, *list,
                                                getter_AddRefs(result));
        }
        if (NS_FAILED(rv))
            continue;
        result.swap(*list);
    }

    PruneProxyInfo(info, list);
}

void
nsProtocolProxyService::PruneProxyInfo(const nsProtocolInfo &info,
                                       nsIProxyInfo **list)
{
    if (!*list)
        return;
    nsProxyInfo *head = nullptr;
    CallQueryInterface(*list, &head);
    if (!head) {
        NS_NOTREACHED("nsIProxyInfo must QI to nsProxyInfo");
        return;
    }
    NS_RELEASE(*list);

    // Pruning of disabled proxies works like this:
    //   - If all proxies are disabled, return the full list
    //   - Otherwise, remove the disabled proxies.
    //
    // Pruning of disallowed proxies works like this:
    //   - If the protocol handler disallows the proxy, then we disallow it.

    // Start by removing all disallowed proxies if required:
    if (!(info.flags & nsIProtocolHandler::ALLOWS_PROXY_HTTP)) {
        nsProxyInfo *last = nullptr, *iter = head;
        while (iter) {
            if ((iter->Type() == kProxyType_HTTP) ||
                (iter->Type() == kProxyType_HTTPS)) {
                // reject!
                if (last)
                    last->mNext = iter->mNext;
                else
                    head = iter->mNext;
                nsProxyInfo *next = iter->mNext;
                iter->mNext = nullptr;
                iter->Release();
                iter = next;
            } else {
                last = iter;
                iter = iter->mNext;
            }
        }
        if (!head)
            return;
    }

    // Now, scan to see if all remaining proxies are disabled.  If so, then
    // we'll just bail and return them all.  Otherwise, we'll go and prune the
    // disabled ones.

    bool allDisabled = true;

    nsProxyInfo *iter;
    for (iter = head; iter; iter = iter->mNext) {
        if (!IsProxyDisabled(iter)) {
            allDisabled = false;
            break;
        }
    }

    if (allDisabled)
        LOG(("All proxies are disabled, so trying all again"));
    else {
        // remove any disabled proxies.
        nsProxyInfo *last = nullptr;
        for (iter = head; iter; ) {
            if (IsProxyDisabled(iter)) {
                // reject!
                nsProxyInfo *reject = iter;

                iter = iter->mNext;
                if (last)
                    last->mNext = iter;
                else
                    head = iter;

                reject->mNext = nullptr;
                NS_RELEASE(reject);
                continue;
            }

            // since we are about to use this proxy, make sure it is not on
            // the disabled proxy list.  we'll add it back to that list if
            // we have to (in GetFailoverForProxy).
            //
            // XXX(darin): It might be better to do this as a final pass.
            //
            EnableProxy(iter);

            last = iter;
            iter = iter->mNext;
        }
    }

    // if only DIRECT was specified then return no proxy info, and we're done.
    if (head && !head->mNext && head->mType == kProxyType_DIRECT)
        NS_RELEASE(head);

    *list = head;  // Transfer ownership
}