--- a/netwerk/base/public/nsIStrictTransportSecurityService.idl
+++ b/netwerk/base/public/nsIStrictTransportSecurityService.idl
@@ -33,16 +33,17 @@
  * the provisions above, a recipient may use your version of this file under
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
 
 #include "nsISupports.idl"
 
 interface nsIURI;
+interface nsIObserver;
 interface nsIHttpChannel;
 
 [scriptable, uuid(16955eee-6c48-4152-9309-c42a465138a1)]
 interface nsIStrictTransportSecurityService : nsISupports
 {
     /**
      * Parses a given HTTP header and records the results internally.
      * The format of the STS header is defined by the STS specification:

--- a/netwerk/protocol/http/nsHttpChannel.cpp
+++ b/netwerk/protocol/http/nsHttpChannel.cpp
@@ -905,23 +905,16 @@ nsHttpChannel::ShouldSSLProxyResponseCon
  *
  * @return NS_ERROR_FAILURE if there's security information missing even though
  *             it's an HTTPS connection.
  */
 nsresult
 nsHttpChannel::ProcessSTSHeader()
 {
     nsresult rv;
-
-    // We need to check private browsing mode here since some permissions are
-    // allowed to be tweaked when private browsing mode is enabled, but STS is
-    // not allowed to operate at all in PBM.
-    if (gHttpHandler->InPrivateBrowsingMode())
-        return NS_OK;
-
     PRBool isHttps = PR_FALSE;
     rv = mURI->SchemeIs("https", &isHttps);
     NS_ENSURE_SUCCESS(rv, rv);
 
     // If this channel is not loading securely, STS doesn't do anything.
     // The upgrade to HTTPS takes place earlier in the channel load process.
     if (!isHttps)
         return NS_OK;

--- a/security/manager/boot/src/nsStrictTransportSecurityService.cpp
+++ b/security/manager/boot/src/nsStrictTransportSecurityService.cpp
@@ -35,16 +35,17 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
 #include "plstr.h"
 #include "prlog.h"
 #include "prprf.h"
 #include "nsCRTGlue.h"
 #include "nsIPermissionManager.h"
+#include "nsIPrivateBrowsingService.h"
 #include "nsISSLStatus.h"
 #include "nsISSLStatusProvider.h"
 #include "nsStrictTransportSecurityService.h"
 #include "nsIURI.h"
 #include "nsInt64.h"
 #include "nsNetUtil.h"
 #include "nsThreadUtils.h"
 #include "nsStringGlue.h"
@@ -56,35 +57,72 @@ PRLogModuleInfo *gSTSLog = PR_NewLogModu
 #define STSLOG(args) PR_LOG(gSTSLog, 4, args)
 
 #define STS_PARSER_FAIL_IF(test,args) \
   if (test) { \
     STSLOG(args); \
     return NS_ERROR_FAILURE; \
   }
 
+
+////////////////////////////////////////////////////////////////////////////////
+
+nsSTSHostEntry::nsSTSHostEntry(const char* aHost)
+  : mHost(aHost)
+  , mExpireTime(0)
+  , mDeleted(PR_FALSE)
+  , mIncludeSubdomains(PR_FALSE)
+{
+}
+
+nsSTSHostEntry::nsSTSHostEntry(const nsSTSHostEntry& toCopy)
+  : mHost(toCopy.mHost)
+  , mExpireTime(toCopy.mExpireTime)
+  , mDeleted(toCopy.mDeleted)
+  , mIncludeSubdomains(toCopy.mIncludeSubdomains)
+{
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+
 nsStrictTransportSecurityService::nsStrictTransportSecurityService()
+  : mInPrivateMode(PR_FALSE)
 {
 }
 
 nsStrictTransportSecurityService::~nsStrictTransportSecurityService()
 {
 }
 
-NS_IMPL_THREADSAFE_ISUPPORTS1(nsStrictTransportSecurityService,
+NS_IMPL_THREADSAFE_ISUPPORTS2(nsStrictTransportSecurityService,
+                              nsIObserver,
                               nsIStrictTransportSecurityService)
 
 nsresult
 nsStrictTransportSecurityService::Init()
 {
    nsresult rv;
 
    mPermMgr = do_GetService(NS_PERMISSIONMANAGER_CONTRACTID, &rv);
    NS_ENSURE_SUCCESS(rv, rv);
 
+   // figure out if we're starting in private browsing mode
+   nsCOMPtr<nsIPrivateBrowsingService> pbs =
+     do_GetService(NS_PRIVATE_BROWSING_SERVICE_CONTRACTID);
+   if (pbs)
+     pbs->GetPrivateBrowsingEnabled(&mInPrivateMode);
+
+   mObserverService = mozilla::services::GetObserverService();
+   if (mObserverService)
+     mObserverService->AddObserver(this, NS_PRIVATE_BROWSING_SWITCH_TOPIC, PR_FALSE);
+
+   if (mInPrivateMode && !mPrivateModeHostTable.Init())
+     return NS_ERROR_OUT_OF_MEMORY;
+
    return NS_OK;
 }
 
 nsresult
 nsStrictTransportSecurityService::GetHost(nsIURI *aURI, nsACString &aResult)
 {
   nsCOMPtr<nsIURI> innerURI = NS_GetInnermostURI(aURI);
   if (!innerURI) return NS_ERROR_FAILURE;
@@ -107,54 +145,62 @@ nsStrictTransportSecurityService::SetSts
   if (!maxage)
     return RemoveStsState(aSourceURI);
 
   // Expire time is millis from now.  Since STS max-age is in seconds, and
   // PR_Now() is in micros, must equalize the units at milliseconds.
   PRInt64 expiretime = (PR_Now() / 1000) + (maxage * 1000);
 
   // record entry for this host with max-age in the permissions manager
-  mPermMgr->Add(aSourceURI, STS_PERMISSION,
+  STSLOG(("STS: maxage permission SET, adding permission\n"));
+  nsresult rv = AddPermission(aSourceURI,
+                              STS_PERMISSION,
                               (PRUint32) nsIPermissionManager::ALLOW_ACTION,
                               (PRUint32) nsIPermissionManager::EXPIRE_TIME,
                               expiretime);
-  STSLOG(("STS: set maxage permission\n"));
+  NS_ENSURE_SUCCESS(rv, rv);
 
   if (includeSubdomains) {
     // record entry for this host with include subdomains in the permissions manager
-    mPermMgr->Add(aSourceURI, STS_SUBDOMAIN_PERMISSION,
-                                (PRUint32) nsIPermissionManager::ALLOW_ACTION,
-                                (PRUint32) nsIPermissionManager::EXPIRE_TIME,
-                                expiretime);
-    STSLOG(("STS: set subdomains permission\n"));
+    STSLOG(("STS: subdomains permission SET, adding permission\n"));
+    rv = AddPermission(aSourceURI,
+                       STS_SUBDOMAIN_PERMISSION,
+                       (PRUint32) nsIPermissionManager::ALLOW_ACTION,
+                       (PRUint32) nsIPermissionManager::EXPIRE_TIME,
+                       expiretime);
+    NS_ENSURE_SUCCESS(rv, rv);
   } else { // !includeSubdomains
     nsCAutoString hostname;
-    nsresult rv = GetHost(aSourceURI, hostname);
+    rv = GetHost(aSourceURI, hostname);
     NS_ENSURE_SUCCESS(rv, rv);
 
-    mPermMgr->Remove(hostname, STS_SUBDOMAIN_PERMISSION);
+    STSLOG(("STS: subdomains permission UNSET, removing any existing ones\n"));
+    rv = RemovePermission(hostname, STS_SUBDOMAIN_PERMISSION);
+    NS_ENSURE_SUCCESS(rv, rv);
   }
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsStrictTransportSecurityService::RemoveStsState(nsIURI* aURI)
 {
   // Should be called on the main thread (or via proxy) since the permission
   // manager is used and it's not threadsafe.
   NS_ENSURE_TRUE(NS_IsMainThread(), NS_ERROR_UNEXPECTED);
 
   nsCAutoString hostname;
   nsresult rv = GetHost(aURI, hostname);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  mPermMgr->Remove(hostname, STS_PERMISSION);
+  rv = RemovePermission(hostname, STS_PERMISSION);
+  NS_ENSURE_SUCCESS(rv, rv);
   STSLOG(("STS: deleted maxage permission\n"));
 
-  mPermMgr->Remove(hostname, STS_SUBDOMAIN_PERMISSION);
+  rv = RemovePermission(hostname, STS_SUBDOMAIN_PERMISSION);
+  NS_ENSURE_SUCCESS(rv, rv);
   STSLOG(("STS: deleted subdomains permission\n"));
 
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsStrictTransportSecurityService::ProcessStsHeader(nsIURI* aSourceURI,
                                                    const char* aHeader)
@@ -290,21 +336,22 @@ nsStrictTransportSecurityService::IsStsU
 {
   // Should be called on the main thread (or via proxy) since the permission
   // manager is used and it's not threadsafe.
   NS_ENSURE_TRUE(NS_IsMainThread(), NS_ERROR_UNEXPECTED);
 
   nsresult rv;
   PRUint32 permExact, permGeneral;
   // If this domain has the forcehttps permission, this is an STS host.
-  rv = mPermMgr->TestExactPermission(aURI, STS_PERMISSION, &permExact);
+  rv = TestPermission(aURI, STS_PERMISSION, &permExact, PR_TRUE);
   NS_ENSURE_SUCCESS(rv, rv);
+
   // If any super-domain has the includeSubdomains permission, this is an
   // STS host.
-  rv = mPermMgr->TestPermission(aURI, STS_SUBDOMAIN_PERMISSION, &permGeneral);
+  rv = TestPermission(aURI, STS_SUBDOMAIN_PERMISSION, &permGeneral, PR_FALSE);
   NS_ENSURE_SUCCESS(rv, rv);
 
   *aResult = ((permExact   == nsIPermissionManager::ALLOW_ACTION) ||
               (permGeneral == nsIPermissionManager::ALLOW_ACTION));
   return NS_OK;
 }
 
 
@@ -336,8 +383,244 @@ nsStrictTransportSecurityService::Should
 
   rv = sslstat->GetIsUntrusted(&trustcheck);
   NS_ENSURE_SUCCESS(rv, rv);
   tlsIsBroken = tlsIsBroken || trustcheck;
 
   *aResult = tlsIsBroken;
   return NS_OK;
 }
+
+//------------------------------------------------------------
+// nsStrictTransportSecurityService::nsIObserver
+//------------------------------------------------------------
+
+NS_IMETHODIMP
+nsStrictTransportSecurityService::Observe(nsISupports *subject,
+                                          const char *topic,
+                                          const PRUnichar *data)
+{
+  if (strcmp(topic, NS_PRIVATE_BROWSING_SWITCH_TOPIC) == 0) {
+    if(NS_LITERAL_STRING(NS_PRIVATE_BROWSING_ENTER).Equals(data)) {
+      // Indication to start recording stuff locally and not writing changes
+      // out to the permission manager.
+
+      if (!mPrivateModeHostTable.IsInitialized()
+          && !mPrivateModeHostTable.Init()) {
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+      mInPrivateMode = PR_TRUE;
+    }
+    else if (NS_LITERAL_STRING(NS_PRIVATE_BROWSING_LEAVE).Equals(data)) {
+      mPrivateModeHostTable.Clear();
+      mInPrivateMode = PR_FALSE;
+    }
+  }
+
+  return NS_OK;
+}
+
+//------------------------------------------------------------
+// Functions to overlay the permission manager calls in case
+// we're in private browsing mode.
+//------------------------------------------------------------
+nsresult
+nsStrictTransportSecurityService::AddPermission(nsIURI     *aURI,
+                                                const char *aType,
+                                                PRUint32   aPermission,
+                                                PRUint32   aExpireType,
+                                                PRInt64    aExpireTime)
+{
+    // Private mode doesn't address user-set (EXPIRE_NEVER) permissions: let
+    // those be stored persistently.
+    if (!mInPrivateMode || aExpireType == nsIPermissionManager::EXPIRE_NEVER) {
+      // Not in private mode, or manually-set permission
+      return mPermMgr->Add(aURI, aType, aPermission, aExpireType, aExpireTime);
+    }
+
+    nsCAutoString host;
+    nsresult rv = GetHost(aURI, host);
+    NS_ENSURE_SUCCESS(rv, rv);
+    STSLOG(("AddPermission for entry for for %s", host.get()));
+
+    // Update in mPrivateModeHostTable only, so any changes will be rolled
+    // back when exiting private mode.
+
+    // Note: EXPIRE_NEVER permissions should trump anything that shows up in
+    // the HTTP header, so if there's an EXPIRE_NEVER permission already
+    // don't store anything new.
+    // Currently there's no way to get the type of expiry out of the
+    // permission manager, but that's okay since there's nothing that stores
+    // EXPIRE_NEVER permissions.
+
+    // PutEntry returns an existing entry if there already is one, or it
+    // creates a new one if there isn't.
+    nsSTSHostEntry* entry = mPrivateModeHostTable.PutEntry(host.get());
+    STSLOG(("Created private mode entry for for %s", host.get()));
+
+    // AddPermission() will be called twice if the STS header encountered has
+    // includeSubdomains (first for the main permission and second for the
+    // subdomains permission). If AddPermission() gets called a second time
+    // with the STS_SUBDOMAIN_PERMISSION, we just have to flip that bit in
+    // the nsSTSHostEntry.
+    if (strcmp(aType, STS_SUBDOMAIN_PERMISSION) == 0) {
+      entry->mIncludeSubdomains = PR_TRUE;
+    }
+    // for the case where PutEntry() returned an existing host entry, make
+    // sure it's not set as deleted (which might have happened in the past).
+    entry->mDeleted = PR_FALSE;
+
+    // Also refresh the expiration time.
+    entry->mExpireTime = aExpireTime;
+    return NS_OK;
+
+}
+
+nsresult
+nsStrictTransportSecurityService::RemovePermission(const nsCString  &aHost,
+                                                   const char       *aType)
+{
+    if (!mInPrivateMode) {
+      // Not in private mode: remove permissions persistently.
+      return mPermMgr->Remove(aHost, aType);
+    }
+
+    // Make changes in mPrivateModeHostTable only, so any changes will be
+    // rolled back when exiting private mode.
+    nsSTSHostEntry* entry = mPrivateModeHostTable.GetEntry(aHost.get());
+
+    // Build up an nsIURI for use with the permission manager.
+    nsCOMPtr<nsIURI> uri;
+    nsresult rv = NS_NewURI(getter_AddRefs(uri),
+                            NS_LITERAL_CSTRING("http://") + aHost);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // Check to see if there's STS data stored for this host in the
+    // permission manager (probably set outside private mode).
+    PRUint32 permmgrValue;
+    rv = mPermMgr->TestExactPermission(uri, aType, &permmgrValue);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    // If there is STS data in the permission manager, store a "deleted" mask
+    // for the permission in mPrivateModeHostTable (either update
+    // mPrivateModeHostTable to have the deleted mask, or add one).
+    // This is because we don't want removals that happen in private mode to
+    // be reflected when private mode is exited -- but while in private mode
+    // we still want the effect of the removal.
+    if (permmgrValue != nsIPermissionManager::UNKNOWN_ACTION) {
+      // if there's no entry in mPrivateModeHostTable, we have to make one.
+      if (!entry) {
+        entry = mPrivateModeHostTable.PutEntry(aHost.get());
+        STSLOG(("Created private mode deleted mask for for %s", aHost.get()));
+      }
+      entry->mDeleted = PR_TRUE;
+      entry->mIncludeSubdomains = PR_FALSE;
+      return NS_OK;
+    }
+
+    // Otherwise, permission doesn't exist in the real permission manager, so
+    // there's nothing to "pretend" to delete.  I'ts ok to delete any copy in
+    // mPrivateModeHostTable.
+    if (entry) mPrivateModeHostTable.RawRemoveEntry(entry);
+    return NS_OK;
+}
+
+nsresult
+nsStrictTransportSecurityService::TestPermission(nsIURI     *aURI,
+                                                 const char *aType,
+                                                 PRUint32   *aPermission,
+                                                 PRBool     testExact)
+{
+    // set default for if we can't find any STS information
+    *aPermission = nsIPermissionManager::UNKNOWN_ACTION;
+
+    if (!mInPrivateMode) {
+      // if not in private mode, just delegate to the permission manager.
+      if (testExact)
+        return mPermMgr->TestExactPermission(aURI, aType, aPermission);
+      else
+        return mPermMgr->TestPermission(aURI, aType, aPermission);
+    }
+
+    nsCAutoString host;
+    nsresult rv = GetHost(aURI, host);
+    if (NS_FAILED(rv)) return NS_OK;
+
+    nsSTSHostEntry *entry;
+    PRUint32 actualExactPermission;
+    PRUint32 offset = 0;
+    PRInt64 now = PR_Now() / 1000;
+
+    // Used for testing permissions as we walk up the domain tree.
+    nsCOMPtr<nsIURI> domainWalkURI;
+
+    // In parallel, loop over private mode cache and also the real permission
+    // manager--ignoring any masked as "deleted" in the local cache. We have
+    // to do this here since the most specific permission in *either* the
+    // permission manager or mPrivateModeHostTable should be used.
+    do {
+      entry = mPrivateModeHostTable.GetEntry(host.get() + offset);
+      STSLOG(("Checking PM Table entry and permmgr for %s", host.get()+offset));
+
+      // flag as deleted any entries encountered that have expired.  We only
+      // flag the nsSTSHostEntry because there could be some data in the
+      // permission manager that -- if not in private mode -- would have been
+      // overwritten by newly encountered STS data.
+      if (entry && (now > entry->mExpireTime)) {
+        STSLOG(("Deleting expired PM Table entry for %s", host.get()+offset));
+        entry->mDeleted = PR_TRUE;
+        entry->mIncludeSubdomains = PR_FALSE;
+      }
+
+      rv = NS_NewURI(getter_AddRefs(domainWalkURI),
+                      NS_LITERAL_CSTRING("http://") + Substring(host, offset));
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      rv = mPermMgr->TestExactPermission(domainWalkURI,
+                                          aType,
+                                          &actualExactPermission);
+      NS_ENSURE_SUCCESS(rv, rv);
+
+      // There are three cases as we walk up the hostname testing
+      // permissions:
+      // 1. There's no entry in mPrivateModeHostTable for this host; rely
+      // on data in the permission manager
+      if (!entry) {
+        if (actualExactPermission != nsIPermissionManager::UNKNOWN_ACTION) {
+          // no cached data but a permission in the permission manager so use
+          // it and stop looking.
+          *aPermission = actualExactPermission;
+          STSLOG(("no PM Table entry for %s, using permmgr", host.get()+offset));
+          break;
+        }
+      }
+      // 2. There's a "deleted" mask in mPrivateModeHostTable for this host
+      // or we're looking for includeSubdomain information and it's not set:
+      // any data in the permission manager must be ignored, since the
+      // permission would have been deleted if not in private mode.
+      else if (entry->mDeleted || (strcmp(aType, STS_SUBDOMAIN_PERMISSION) == 0
+                                  && !entry->mIncludeSubdomains)) {
+        STSLOG(("no entry at all for %s, walking up", host.get()+offset));
+        // keep looking
+      }
+      // 3. There's a non-deleted entry in mPrivateModeHostTable for this
+      // host, so it should be used.
+      else {
+        // All STS permissions' values are ALLOW_ACTION or they are not
+        // known (as in, not set or turned off).
+        *aPermission = nsIPermissionManager::ALLOW_ACTION;
+        STSLOG(("PM Table entry for %s: forcing", host.get()+offset));
+        break;
+      }
+
+      // Don't continue walking up the host segments if the test was for an
+      // exact match only.
+      if (testExact) break;
+
+      STSLOG(("no PM Table entry or permmgr data for %s, walking up domain",
+              host.get()+offset));
+      // walk up the host segments
+      offset = host.FindChar('.', offset) + 1;
+    } while (offset > 0);
+
+    // Use whatever we ended up with, which defaults to UNKNOWN_ACTION.
+    return NS_OK;
+}

--- a/security/manager/boot/src/nsStrictTransportSecurityService.h
+++ b/security/manager/boot/src/nsStrictTransportSecurityService.h
@@ -38,36 +38,128 @@
 /**
  * This wraps nsSimpleURI so that all calls to it are done on the main thread.
  */
 
 #ifndef __nsStrictTransportSecurityService_h__
 #define __nsStrictTransportSecurityService_h__
 
 #include "nsIStrictTransportSecurityService.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
 #include "nsIPermissionManager.h"
 #include "nsCOMPtr.h"
 #include "nsIURI.h"
 #include "nsString.h"
+#include "nsTHashtable.h"
 
 // {16955eee-6c48-4152-9309-c42a465138a1}
 #define NS_STRICT_TRANSPORT_SECURITY_CID \
   {0x16955eee, 0x6c48, 0x4152, \
     {0x93, 0x09, 0xc4, 0x2a, 0x46, 0x51, 0x38, 0xa1} }
 
+////////////////////////////////////////////////////////////////////////////////
+// nsSTSHostEntry - similar to the nsHostEntry class in
+// nsPermissionManager.cpp, but specific to private-mode caching of STS
+// permissions.
+//
+// Each nsSTSHostEntry contains:
+//  - Expiry time
+//  - Deleted flag (boolean, default PR_FALSE)
+//  - Subdomains flag (boolean, default PR_FALSE)
+//
+// The existence of the nsSTSHostEntry implies STS state is set for the given
+// host -- unless the deleted flag is set, in which case not only is the STS
+// state not set for the host, but any permission actually present in the
+// permission manager should be ignored.
+//
+// Note: Only one expiry time is stored since the subdomains and STS
+// permissions are both encountered at the same time in the HTTP header; if the
+// includeSubdomains directive isn't present in the header, it means to delete
+// the permission, so the subdomains flag in the nsSTSHostEntry means both that
+// the permission doesn't exist and any permission in the real permission
+// manager should be ignored since newer information about it has been
+// encountered in private browsing mode.
+//
+// Note: If there's a permission set by the user (EXPIRE_NEVER), STS is not set
+// for the host (including the subdomains permission) when the header is
+// encountered.  Furthermore, any user-set permissions are stored persistently
+// and can't be shadowed.
+
+class nsSTSHostEntry : public PLDHashEntryHdr
+{
+  public:
+    explicit nsSTSHostEntry(const char* aHost);
+    explicit nsSTSHostEntry(const nsSTSHostEntry& toCopy);
+
+    nsCString    mHost;
+    PRInt64      mExpireTime;
+    PRPackedBool mDeleted;
+    PRPackedBool mIncludeSubdomains;
+
+    // Hash methods
+    typedef const char* KeyType;
+    typedef const char* KeyTypePointer;
+
+    KeyType GetKey() const
+    {
+      return mHost.get();
+    }
+
+    PRBool KeyEquals(KeyTypePointer aKey) const
+    {
+      return !strcmp(mHost.get(), aKey);
+    }
+
+    static KeyTypePointer KeyToPointer(KeyType aKey)
+    {
+      return aKey;
+    }
+
+    static PLDHashNumber HashKey(KeyTypePointer aKey)
+    {
+      return PL_DHashStringKey(nsnull, aKey);
+    }
+
+    // force the hashtable to use the copy constructor.
+    enum { ALLOW_MEMMOVE = PR_FALSE };
+};
+////////////////////////////////////////////////////////////////////////////////
+
 class nsStrictTransportSecurityService : public nsIStrictTransportSecurityService
+                                       , public nsIObserver
 {
 public:
   NS_DECL_ISUPPORTS
+  NS_DECL_NSIOBSERVER
   NS_DECL_NSISTRICTTRANSPORTSECURITYSERVICE
 
   nsStrictTransportSecurityService();
   nsresult Init();
   virtual ~nsStrictTransportSecurityService();
 
 private:
   nsresult GetHost(nsIURI *aURI, nsACString &aResult);
   nsresult SetStsState(nsIURI* aSourceURI, PRInt64 maxage, PRBool includeSubdomains);
   nsresult ProcessStsHeaderMutating(nsIURI* aSourceURI, char* aHeader);
+
+  // private-mode-preserving permission manager overlay functions
+  nsresult AddPermission(nsIURI     *aURI,
+                         const char *aType,
+                         PRUint32   aPermission,
+                         PRUint32   aExpireType,
+                         PRInt64    aExpireTime);
+  nsresult RemovePermission(const nsCString  &aHost,
+                            const char       *aType);
+  nsresult TestPermission(nsIURI     *aURI,
+                          const char *aType,
+                          PRUint32   *aPermission,
+                          PRBool     testExact);
+
+  // cached services
   nsCOMPtr<nsIPermissionManager> mPermMgr;
+  nsCOMPtr<nsIObserverService> mObserverService;
+
+  PRBool mInPrivateMode;
+  nsTHashtable<nsSTSHostEntry> mPrivateModeHostTable;
 };
 
 #endif // __nsStrictTransportSecurityService_h__

--- a/security/manager/ssl/tests/mochitest/stricttransportsecurity/Makefile.in
+++ b/security/manager/ssl/tests/mochitest/stricttransportsecurity/Makefile.in
@@ -44,14 +44,17 @@ relativesrcdir	= security/ssl/stricttran
 include $(DEPTH)/config/autoconf.mk
 include $(topsrcdir)/config/rules.mk
 
 _TEST_FILES = \
 	plain_bootstrap.html \
 	plain_bootstrap.html^headers^ \
 	subdom_bootstrap.html \
 	subdom_bootstrap.html^headers^ \
+	nosts_bootstrap.html \
+	nosts_bootstrap.html^headers^ \
 	verify.sjs \
 	test_stricttransportsecurity.html \
+	test_sts_privatebrowsing.html \
 	$(NULL)
 
 libs:: $(_TEST_FILES)
 	$(INSTALL) $(foreach f,$^,"$f") $(DEPTH)/_tests/testing/mochitest/tests/$(relativesrcdir)

new file mode 100644
--- /dev/null
+++ b/security/manager/ssl/tests/mochitest/stricttransportsecurity/nosts_bootstrap.html
@@ -0,0 +1,57 @@
+<!-- ***** BEGIN LICENSE BLOCK *****
+   - Version: MPL 1.1/GPL 2.0/LGPL 2.1
+   -
+   - The contents of this file are subject to the Mozilla Public License Version
+   - 1.1 (the "License"); you may not use this file except in compliance with
+   - the License. You may obtain a copy of the License at
+   - http://www.mozilla.org/MPL/
+   -
+   - Software distributed under the License is distributed on an "AS IS" basis,
+   - WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+   - for the specific language governing rights and limitations under the
+   - License.
+   -
+   - The Original Code is Strict-Transport-Security.
+   -
+   - The Initial Developer of the Original Code is
+   - Mozilla Foundation.
+   - Portions created by the Initial Developer are Copyright (C) 2010
+   - the Initial Developer. All Rights Reserved.
+   -
+   - Contributor(s):
+   -  Sid Stamm <sid@mozilla.com>
+   -
+   - Alternatively, the contents of this file may be used under the terms of
+   - either the GNU General Public License Version 2 or later (the "GPL"), or
+   - the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+   - in which case the provisions of the GPL or the LGPL are applicable instead
+   - of those above. If you wish to allow use of your version of this file only
+   - under the terms of either the GPL or the LGPL, and not to allow others to
+   - use your version of this file under the terms of the MPL, indicate your
+   - decision by deleting the provisions above and replace them with the notice
+   - and other provisions required by the LGPL or the GPL. If you do not delete
+   - the provisions above, a recipient may use your version of this file under
+   - the terms of any one of the MPL, the GPL or the LGPL.
+   -
+   - ***** END LICENSE BLOCK ***** -->
+
+<!DOCTYPE HTML>
+<html>
+  <head>
+    <title>STS test iframe</title>
+    <script>
+      var self = window;
+      window.addEventListener("load", function() {
+          self.parent.postMessage("BOOTSTRAP plain", "http://mochi.test:8888");
+        }, false);
+    </script>
+  </head>
+  <body>
+    <!-- This frame should be loaded over HTTPS to set the STS header. -->
+    This frame was loaded using 
+    <script>
+      document.write(document.location.protocol);
+    </script>
+    and set the STS header to force this site and allow subdomain upgrading.
+  </body>
+</html>

new file mode 100644
--- /dev/null
+++ b/security/manager/ssl/tests/mochitest/stricttransportsecurity/nosts_bootstrap.html^headers^
@@ -0,0 +1,1 @@
+Cache-Control: no-cache

new file mode 100644
--- /dev/null
+++ b/security/manager/ssl/tests/mochitest/stricttransportsecurity/test_sts_privatebrowsing.html
@@ -0,0 +1,269 @@
+<!-- ***** BEGIN LICENSE BLOCK *****
+   - Version: MPL 1.1/GPL 2.0/LGPL 2.1
+   -
+   - The contents of this file are subject to the Mozilla Public License Version
+   - 1.1 (the "License"); you may not use this file except in compliance with
+   - the License. You may obtain a copy of the License at
+   - http://www.mozilla.org/MPL/
+   -
+   - Software distributed under the License is distributed on an "AS IS" basis,
+   - WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+   - for the specific language governing rights and limitations under the
+   - License.
+   -
+   - The Original Code is Strict-Transport-Security.
+   -
+   - The Initial Developer of the Original Code is
+   - Mozilla Foundation.
+   - Portions created by the Initial Developer are Copyright (C) 2010
+   - the Initial Developer. All Rights Reserved.
+   -
+   - Contributor(s):
+   -  Sid Stamm <sid@mozilla.com>
+   -
+   - Alternatively, the contents of this file may be used under the terms of
+   - either the GNU General Public License Version 2 or later (the "GPL"), or
+   - the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+   - in which case the provisions of the GPL or the LGPL are applicable instead
+   - of those above. If you wish to allow use of your version of this file only
+   - under the terms of either the GPL or the LGPL, and not to allow others to
+   - use your version of this file under the terms of the MPL, indicate your
+   - decision by deleting the provisions above and replace them with the notice
+   - and other provisions required by the LGPL or the GPL. If you do not delete
+   - the provisions above, a recipient may use your version of this file under
+   - the terms of any one of the MPL, the GPL or the LGPL.
+   -
+   - ***** END LICENSE BLOCK ***** -->
+
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>opens additional content that should be converted to https</title>
+  <script type="text/javascript" src="/MochiKit/packed.js"></script>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+
+  <script class="testbody" type="text/javascript">
+  SimpleTest.waitForExplicitFinish();
+
+  const STSPATH = "/tests/security/ssl/stricttransportsecurity";
+
+  const NUM_TEST_FRAMES = 4;
+  var testframes = {
+    'samedom':
+      {'url':     "http://example.com" + STSPATH + "/verify.sjs",
+        'expected': {'plain': 'SECURE',
+                     'subdom': 'SECURE',
+                     'nosts': 'INSECURE'}},
+    'subdom':
+      {'url':     "http://test1.example.com" + STSPATH + "/verify.sjs",
+        'expected': {'plain': 'INSECURE',
+                     'subdom': 'SECURE',
+                     'nosts': 'INSECURE'}},
+    'otherdom':
+      {'url':     "http://example.org" + STSPATH + "/verify.sjs",
+        'expected': {'plain': 'INSECURE',
+                     'subdom': 'INSECURE',
+                     'nosts': 'INSECURE'}},
+    'alreadysecure':
+      {'url':     "https://test2.example.com" + STSPATH + "/verify.sjs",
+        'expected': {'plain': 'SECURE',
+                     'subdom': 'SECURE',
+                     'nosts': 'SECURE'}},
+  };
+
+  // This is how many sub-tests (testframes) in each round.
+  // When the round begins, this will be initialized.
+  var testsleftinround = 0;
+  var currentround = "";
+
+  var _PBSvc = null;
+  var _PrefSvc = null;
+
+  function _getPBService() {
+    if (_PBSvc)
+      return _PBSvc;
+
+    // not all apps will have the private browsing service.
+    try {
+      netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+      _PBSvc = Components.classes["@mozilla.org/privatebrowsing;1"]
+        .getService(Components.interfaces.nsIPrivateBrowsingService);
+      return _PBSvc;
+    } catch (e) {}
+    return null;
+  }
+  function _getPrefService() {
+    if (_PrefSvc)
+      return _PrefSvc;
+
+    // not all apps will have the private browsing service.
+    try {
+      netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+      _PrefSvc = Components.classes["@mozilla.org/preferences-service;1"]
+        .getService(Components.interfaces.nsIPrefService)
+        .QueryInterface(Components.interfaces.nsIPrefBranch2);
+      return _PrefSvc;
+    } catch (e) {}
+    return null;
+  }
+
+  function startRound(round) {
+    currentround = round;
+    testsleftinround = NUM_TEST_FRAMES;
+    dump("TESTS LEFT IN ROUND: " + testsleftinround + "\n");
+    var frame = document.createElement("iframe");
+    frame.setAttribute('id', 'ifr_bootstrap');
+    frame.setAttribute('src', "https://example.com" + STSPATH +
+                              "/" + round + "_bootstrap.html");
+    document.body.appendChild(frame);
+  }
+
+  function loadVerifyFrames(round) {
+    for (var test in testframes) {
+      var frame = document.createElement("iframe");
+      frame.setAttribute('id', 'ifr_' + test);
+      frame.setAttribute('src', testframes[test].url + '?id=' + test);
+      document.body.appendChild(frame);
+    }
+  }
+
+  /* Messages received are in this format:
+   *  (BOOTSTRAP|SECURE|INSECURE) testid
+   * For example: "BOOTSTRAP subdom"
+   *          or: "INSECURE otherdom"
+   */
+  function onMessageReceived(event) {
+
+    // otherwise, it's a test result
+    var result = event.data.split(/\s+/);
+    if (result.length != 2) {
+      SimpleTest.ok(false, event.data);
+      return;
+    }
+
+    if (result[0] === "BOOTSTRAP") {
+      loadVerifyFrames(currentround);
+      return;
+    }
+
+    // check if the result (SECURE/INSECURE) is expected for this round/test
+    // combo
+    dump_STSState();
+    dump( "*** in ROUND " + currentround +
+          ", test " + result[1] +
+          " is " + result[0] + "\n");
+    SimpleTest.is(result[0], testframes[result[1]].expected[currentround],
+                             "in ROUND " + currentround +
+                             ", test " + result[1]);
+    testsleftinround--;
+
+    // if this round is complete...
+    if (testsleftinround < 1) {
+      dump("DONE WITH ROUND " + currentround + "\n");
+      // remove all the iframes in the document
+      document.body.removeChild(document.getElementById('ifr_bootstrap'));
+      for (var test in testframes)
+        document.body.removeChild(document.getElementById('ifr_' + test));
+      currentround = "";
+
+      // And advance to the next test.
+      // Defer this so it doesn't muck with the stack too much.
+      SimpleTest.executeSoon(nextTest);
+    }
+  }
+
+  function test_sts_before_private_mode() {
+    dump_STSState();
+    dump("*** not in private browsing mode\n");
+    startRound('plain');
+  }
+
+  function test_sts_in_private_mode() {
+    dump_STSState();
+    dump("*** Entering private browsing mode\n");
+    netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+    _getPrefService().setBoolPref("browser.privatebrowsing.keep_current_session",
+                               true);
+    _getPBService().privateBrowsingEnabled = true;
+    dump("*** ... done\n");
+    dump_STSState();
+    startRound('subdom');
+  }
+
+  function test_sts_after_exiting_private_mode() {
+    dump_STSState();
+    dump("*** Exiting private browsing mode\n");
+    netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+    _getPBService().privateBrowsingEnabled = false;
+    _getPrefService().clearUserPref("browser.privatebrowsing.keep_current_session");
+    dump("*** ... done\n");
+    dump_STSState();
+    startRound('nosts');
+  }
+
+  function clean_up_sts_state() {
+    // erase all signs that this test ran.
+    dump("*** Cleaning up STS data.\n");
+    netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+    const Cc = Components.classes;
+    const Ci = Components.interfaces;
+    var ios = Cc["@mozilla.org/network/io-service;1"]
+                .getService(Ci.nsIIOService);
+    var thehost = ios.newURI("http://example.com", null, null);
+    var stss = Cc["@mozilla.org/stsservice;1"]
+                 .getService(Ci.nsIStrictTransportSecurityService);
+    stss.removeStsState(thehost);
+    dump_STSState();
+    SimpleTest.executeSoon(nextTest);
+  }
+
+function dump_STSState() {
+    netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+    var stss = Components.classes["@mozilla.org/stsservice;1"]
+          .getService(Components.interfaces.nsIStrictTransportSecurityService);
+    dump("*** State of example.com: " + stss.isStsHost("example.com") + "\n");
+}
+
+  // these are executed in the order presented.
+  // 0.  test that STS works before entering private browsing mode.
+  //     (load sts-bootstrapped "plain" tests)
+  //  ... clear any STS data ...
+  // 1.  test that STS works in private browsing mode
+  //     (load sts-bootstrapped "subdomain" tests)
+  // 2.  test that after exiting private browsing, STS data is forgotten
+  //     (verified with non-sts-bootstrapped pages)
+  var tests = [];
+  { // skip these tests if there's no private mode support
+    netscape.security.PrivilegeManager.enablePrivilege('UniversalXPConnect');
+    if ("@mozilla.org/privatebrowsing;1" in Components.classes) {
+      tests = [
+        test_sts_before_private_mode,
+        clean_up_sts_state,
+        test_sts_in_private_mode,
+        test_sts_after_exiting_private_mode,
+        clean_up_sts_state,
+      ];
+    }
+  }
+
+  function nextTest() {
+    if (tests.length)
+      SimpleTest.executeSoon(tests.shift());
+    else
+      SimpleTest.executeSoon(SimpleTest.finish);
+  }
+
+  // listen for calls back from the sts-setting iframe and then
+  // the verification frames.
+  window.addEventListener("message", onMessageReceived, false);
+  window.addEventListener('load', nextTest, false);
+
+  </script>
+</head>
+
+<body>
+  This test will load some iframes and do some tests.
+
+</body>
+</html>