Introduce tolower_ascii_unsafe() and use it for hashing

[apt.git] / apt-pkg / acquire-item.cc

diff --git a/apt-pkg/acquire-item.cc b/apt-pkg/acquire-item.cc
index ad8cb7f245795298c4c5a54d361b86012881e534..154b9a16e8e08e72c3dd9ac34665b608610853c8 100644 (file)
--- a/apt-pkg/acquire-item.cc
+++ b/apt-pkg/acquire-item.cc
@@ -46,6 +46,7 @@
 #include <ctime>
 #include <sstream>
 #include <numeric>
 #include <ctime>
 #include <sstream>
 #include <numeric>

+#include <random>

 
 #include <apti18n.h>
                                                                        /*}}}*/
 
 #include <apti18n.h>
                                                                        /*}}}*/


@@ -145,7 +146,7 @@ static void ReportMirrorFailureToCentral(pkgAcquire::Item const &I, std::string
             << FailCode << std::endl;
 #endif
    string const report = _config->Find("Methods::Mirror::ProblemReporting",
             << FailCode << std::endl;
 #endif
    string const report = _config->Find("Methods::Mirror::ProblemReporting",

-                                "/usr/lib/apt/apt-report-mirror-failure");
+                                LIBEXEC_DIR "/apt-report-mirror-failure");

    if(!FileExists(report))
       return;
 
    if(!FileExists(report))
       return;
 


@@ -410,7 +411,7 @@ bool pkgAcqTransactionItem::QueueURI(pkgAcquire::ItemDesc &Item)
       return false;
    }
    // If we got the InRelease file via a mirror, pick all indexes directly from this mirror, too
       return false;
    }
    // If we got the InRelease file via a mirror, pick all indexes directly from this mirror, too

-   if (TransactionManager->BaseURI.empty() == false &&
+   if (TransactionManager->BaseURI.empty() == false && UsedMirror.empty() &&

         URI::SiteOnly(Item.URI) != URI::SiteOnly(TransactionManager->BaseURI))
    {
       // this ensures we rewrite only once and only the first step
         URI::SiteOnly(Item.URI) != URI::SiteOnly(TransactionManager->BaseURI))
    {
       // this ensures we rewrite only once and only the first step


@@ -451,7 +452,11 @@ std::string pkgAcquire::Item::GetFinalFilename() const
 }
 std::string pkgAcqDiffIndex::GetFinalFilename() const
 {
 }
 std::string pkgAcqDiffIndex::GetFinalFilename() const
 {

-   return GetFinalFileNameFromURI(GetDiffIndexURI(Target));
+   std::string const FinalFile = GetFinalFileNameFromURI(GetDiffIndexURI(Target));
+   // we don't want recompress, so lets keep whatever we got
+   if (CurrentCompressionExtension == "uncompressed")
+      return FinalFile;
+   return FinalFile + "." + CurrentCompressionExtension;

 }
 std::string pkgAcqIndex::GetFinalFilename() const
 {
 }
 std::string pkgAcqIndex::GetFinalFilename() const
 {


@@ -488,7 +493,10 @@ std::string pkgAcqIndex::GetMetaKey() const
 }
 std::string pkgAcqDiffIndex::GetMetaKey() const
 {
 }
 std::string pkgAcqDiffIndex::GetMetaKey() const
 {

-   return GetDiffIndexFileName(Target.MetaKey);
+   auto const metakey = GetDiffIndexFileName(Target.MetaKey);
+   if (CurrentCompressionExtension == "uncompressed")
+      return metakey;
+   return metakey + "." + CurrentCompressionExtension;

 }
                                                                        /*}}}*/
 //pkgAcqTransactionItem::TransactionState and specialisations for child classes        /*{{{*/
 }
                                                                        /*}}}*/
 //pkgAcqTransactionItem::TransactionState and specialisations for child classes        /*{{{*/


@@ -685,10 +693,15 @@ class APT_HIDDEN CleanupItem : public pkgAcqTransactionItem               /*{{{*/
                                                                        /*}}}*/
 
 // Acquire::Item::Item - Constructor                                   /*{{{*/
                                                                        /*}}}*/
 
 // Acquire::Item::Item - Constructor                                   /*{{{*/

+class pkgAcquire::Item::Private
+{
+public:
+   std::vector<std::string> PastRedirections;
+};

 APT_IGNORE_DEPRECATED_PUSH
 pkgAcquire::Item::Item(pkgAcquire * const owner) :
    FileSize(0), PartialSize(0), Mode(0), ID(0), Complete(false), Local(false),
 APT_IGNORE_DEPRECATED_PUSH
 pkgAcquire::Item::Item(pkgAcquire * const owner) :
    FileSize(0), PartialSize(0), Mode(0), ID(0), Complete(false), Local(false),

-    QueueCounter(0), ExpectedAdditionalItems(0), Owner(owner), d(NULL)
+    QueueCounter(0), ExpectedAdditionalItems(0), Owner(owner), d(new Private())

 {
    Owner->Add(this);
    Status = StatIdle;
 {
    Owner->Add(this);
    Status = StatIdle;


@@ -699,6 +712,7 @@ APT_IGNORE_DEPRECATED_POP
 pkgAcquire::Item::~Item()
 {
    Owner->Remove(this);
 pkgAcquire::Item::~Item()
 {
    Owner->Remove(this);

+   delete d;

 }
                                                                        /*}}}*/
 std::string pkgAcquire::Item::Custom600Headers() const                 /*{{{*/
 }
                                                                        /*}}}*/
 std::string pkgAcquire::Item::Custom600Headers() const                 /*{{{*/


@@ -734,6 +748,18 @@ APT_CONST bool pkgAcquire::Item::IsTrusted() const                 /*{{{*/
 // ---------------------------------------------------------------------
 /* We return to an idle state if there are still other queues that could
    fetch this object */
 // ---------------------------------------------------------------------
 /* We return to an idle state if there are still other queues that could
    fetch this object */

+static void formatHashsum(std::ostream &out, HashString const &hs)
+{
+   auto const type = hs.HashType();
+   if (type == "Checksum-FileSize")
+      out << " - Filesize";
+   else
+      out << " - " << type;
+   out << ':' << hs.HashValue();
+   if (hs.usable() == false)
+      out << " [weak]";
+   out << std::endl;
+}

 void pkgAcquire::Item::Failed(string const &Message,pkgAcquire::MethodConfig const * const Cnf)
 {
    if (QueueCounter <= 1)
 void pkgAcquire::Item::Failed(string const &Message,pkgAcquire::MethodConfig const * const Cnf)
 {
    if (QueueCounter <= 1)


@@ -766,43 +792,46 @@ void pkgAcquire::Item::Failed(string const &Message,pkgAcquire::MethodConfig con
    }
 
    string const FailReason = LookupTag(Message, "FailReason");
    }
 
    string const FailReason = LookupTag(Message, "FailReason");

-   enum { MAXIMUM_SIZE_EXCEEDED, HASHSUM_MISMATCH, WEAK_HASHSUMS, OTHER } failreason = OTHER;
+   enum { MAXIMUM_SIZE_EXCEEDED, HASHSUM_MISMATCH, WEAK_HASHSUMS, REDIRECTION_LOOP, OTHER } failreason = OTHER;

    if ( FailReason == "MaximumSizeExceeded")
       failreason = MAXIMUM_SIZE_EXCEEDED;
    else if ( FailReason == "WeakHashSums")
       failreason = WEAK_HASHSUMS;
    if ( FailReason == "MaximumSizeExceeded")
       failreason = MAXIMUM_SIZE_EXCEEDED;
    else if ( FailReason == "WeakHashSums")
       failreason = WEAK_HASHSUMS;

+   else if (FailReason == "RedirectionLoop")
+      failreason = REDIRECTION_LOOP;

    else if (Status == StatAuthError)
       failreason = HASHSUM_MISMATCH;
 
    if(ErrorText.empty())
    {
    else if (Status == StatAuthError)
       failreason = HASHSUM_MISMATCH;
 
    if(ErrorText.empty())
    {

+      std::ostringstream out;
+      switch (failreason)
+      {
+        case HASHSUM_MISMATCH:
+           out << _("Hash Sum mismatch") << std::endl;
+           break;
+        case WEAK_HASHSUMS:
+           out << _("Insufficient information available to perform this download securely") << std::endl;
+           break;
+        case REDIRECTION_LOOP:
+           out << "Redirection loop encountered" << std::endl;
+           break;
+        case MAXIMUM_SIZE_EXCEEDED:
+           out << LookupTag(Message, "Message") << std::endl;
+           break;
+        case OTHER:
+           out << LookupTag(Message, "Message");
+           break;
+      }
+

       if (Status == StatAuthError)
       {
       if (Status == StatAuthError)
       {

-        std::ostringstream out;
-        switch (failreason)
-        {
-           case HASHSUM_MISMATCH:
-              out << _("Hash Sum mismatch") << std::endl;
-              break;
-           case WEAK_HASHSUMS:
-              out << _("Insufficient information available to perform this download securely") << std::endl;
-              break;
-           case MAXIMUM_SIZE_EXCEEDED:
-           case OTHER:
-              out << LookupTag(Message, "Message") << std::endl;
-              break;
-        }

         auto const ExpectedHashes = GetExpectedHashes();
         if (ExpectedHashes.empty() == false)
         {
            out << "Hashes of expected file:" << std::endl;
            for (auto const &hs: ExpectedHashes)
         auto const ExpectedHashes = GetExpectedHashes();
         if (ExpectedHashes.empty() == false)
         {
            out << "Hashes of expected file:" << std::endl;
            for (auto const &hs: ExpectedHashes)

-           {
-              out << " - " << hs.toStr();
-              if (hs.usable() == false)
-                 out << " [weak]";
-              out << std::endl;
-           }
+              formatHashsum(out, hs);

         }
         if (failreason == HASHSUM_MISMATCH)
         {
         }
         if (failreason == HASHSUM_MISMATCH)
         {


@@ -812,20 +841,14 @@ void pkgAcquire::Item::Failed(string const &Message,pkgAcquire::MethodConfig con
               std::string const tagname = std::string(*type) + "-Hash";
               std::string const hashsum = LookupTag(Message, tagname.c_str());
               if (hashsum.empty() == false)
               std::string const tagname = std::string(*type) + "-Hash";
               std::string const hashsum = LookupTag(Message, tagname.c_str());
               if (hashsum.empty() == false)

-              {
-                 auto const hs = HashString(*type, hashsum);
-                 out << " - " << hs.toStr();
-                 if (hs.usable() == false)
-                    out << " [weak]";
-                 out << std::endl;
-              }
+                 formatHashsum(out, HashString(*type, hashsum));

            }
            }

-           out << "Last modification reported: " << LookupTag(Message, "Last-Modified", "<none>") << std::endl;

         }
         }

-        ErrorText = out.str();
+        auto const lastmod = LookupTag(Message, "Last-Modified", "");
+        if (lastmod.empty() == false)
+           out << "Last modification reported: " << lastmod << std::endl;

       }
       }

-      else
-        ErrorText = LookupTag(Message,"Message");
+      ErrorText = out.str();

    }
 
    switch (failreason)
    }
 
    switch (failreason)


@@ -833,6 +856,7 @@ void pkgAcquire::Item::Failed(string const &Message,pkgAcquire::MethodConfig con
       case MAXIMUM_SIZE_EXCEEDED: RenameOnError(MaximumSizeExceeded); break;
       case HASHSUM_MISMATCH: RenameOnError(HashSumMismatch); break;
       case WEAK_HASHSUMS: break;
       case MAXIMUM_SIZE_EXCEEDED: RenameOnError(MaximumSizeExceeded); break;
       case HASHSUM_MISMATCH: RenameOnError(HashSumMismatch); break;
       case WEAK_HASHSUMS: break;

+      case REDIRECTION_LOOP: break;

       case OTHER: break;
    }
 
       case OTHER: break;
    }
 


@@ -976,6 +1000,49 @@ std::string pkgAcquire::Item::HashSum() const                             /*{{{*/
    return hs != NULL ? hs->toStr() : "";
 }
                                                                        /*}}}*/
    return hs != NULL ? hs->toStr() : "";
 }
                                                                        /*}}}*/

+bool pkgAcquire::Item::IsRedirectionLoop(std::string const &NewURI)    /*{{{*/
+{
+   // store can fail due to permission errors and the item will "loop" then
+   if (APT::String::Startswith(NewURI, "store:"))
+      return false;
+   if (d->PastRedirections.empty())
+   {
+      d->PastRedirections.push_back(NewURI);
+      return false;
+   }
+   auto const LastURI = std::prev(d->PastRedirections.end());
+   // redirections to the same file are a way of restarting/resheduling,
+   // individual methods will have to make sure that they aren't looping this way
+   if (*LastURI == NewURI)
+      return false;
+   if (std::find(d->PastRedirections.begin(), LastURI, NewURI) != LastURI)
+      return true;
+   d->PastRedirections.push_back(NewURI);
+   return false;
+}
+                                                                       /*}}}*/
+
+                                                                                                                                               /*}}}*/
+int pkgAcquire::Item::Priority()                               /*{{{*/
+{
+   // Stage 1: Meta indices and diff indices
+   // - those need to be fetched first to have progress reporting working
+   //   for the rest
+   if (dynamic_cast<pkgAcqMetaSig*>(this) != nullptr
+       || dynamic_cast<pkgAcqMetaBase*>(this) != nullptr
+       || dynamic_cast<pkgAcqDiffIndex*>(this) != nullptr)
+      return 1000;
+   // Stage 2: Diff files
+   // - fetch before complete indexes so we can apply the diffs while fetching
+   //   larger files.
+   if (dynamic_cast<pkgAcqIndexDiffs*>(this) != nullptr ||
+       dynamic_cast<pkgAcqIndexMergeDiffs*>(this) != nullptr)
+      return 800;
+
+   // Stage 3: The rest - complete index files and other stuff
+   return 500;
+}
+                                                                       /*}}}*/

 
 pkgAcqTransactionItem::pkgAcqTransactionItem(pkgAcquire * const Owner, /*{{{*/
       pkgAcqMetaClearSig * const transactionManager, IndexTarget const &target) :
 
 pkgAcqTransactionItem::pkgAcqTransactionItem(pkgAcquire * const Owner, /*{{{*/
       pkgAcqMetaClearSig * const transactionManager, IndexTarget const &target) :


@@ -1192,9 +1259,15 @@ bool pkgAcqMetaBase::CheckDownloadDone(pkgAcqTransactionItem * const I, const st
    if (I->UsedMirror.empty() == false && _config->FindB("Acquire::SameMirrorForAllIndexes", true))
    {
       if (APT::String::Endswith(I->Desc.URI, "InRelease"))
    if (I->UsedMirror.empty() == false && _config->FindB("Acquire::SameMirrorForAllIndexes", true))
    {
       if (APT::String::Endswith(I->Desc.URI, "InRelease"))

+      {

         TransactionManager->BaseURI = I->Desc.URI.substr(0, I->Desc.URI.length() - strlen("InRelease"));
         TransactionManager->BaseURI = I->Desc.URI.substr(0, I->Desc.URI.length() - strlen("InRelease"));

+        TransactionManager->UsedMirror = I->UsedMirror;
+      }

       else if (APT::String::Endswith(I->Desc.URI, "Release"))
       else if (APT::String::Endswith(I->Desc.URI, "Release"))

+      {

         TransactionManager->BaseURI = I->Desc.URI.substr(0, I->Desc.URI.length() - strlen("Release"));
         TransactionManager->BaseURI = I->Desc.URI.substr(0, I->Desc.URI.length() - strlen("Release"));

+        TransactionManager->UsedMirror = I->UsedMirror;
+      }

    }
 
    std::string const FileName = LookupTag(Message,"Filename");
    }
 
    std::string const FileName = LookupTag(Message,"Filename");


@@ -1293,6 +1366,23 @@ void pkgAcqMetaClearSig::QueueIndexes(bool const verify)                 /*{{{*/
    if (hasReleaseFile && verify == false)
       hasHashes = std::any_of(IndexTargets.begin(), IndexTargets.end(),
            [&](IndexTarget const &Target) { return TransactionManager->MetaIndexParser->Exists(Target.MetaKey); });
    if (hasReleaseFile && verify == false)
       hasHashes = std::any_of(IndexTargets.begin(), IndexTargets.end(),
            [&](IndexTarget const &Target) { return TransactionManager->MetaIndexParser->Exists(Target.MetaKey); });

+   if (_config->FindB("Acquire::IndexTargets::Randomized", true) && likely(IndexTargets.empty() == false))
+   {
+      /* For fallback handling and to have some reasonable progress information
+        we can't randomize everything, but at least the order in the same type
+        can be as we shouldn't be telling the mirrors (and everyone else watching)
+        which is native/foreign arch, specific order of preference of translations, … */
+      auto range_start = IndexTargets.begin();
+      std::random_device rd;
+      std::default_random_engine g(rd());
+      do {
+        auto const type = range_start->Option(IndexTarget::CREATED_BY);
+        auto const range_end = std::find_if_not(range_start, IndexTargets.end(),
+              [&type](IndexTarget const &T) { return type == T.Option(IndexTarget::CREATED_BY); });
+        std::shuffle(range_start, range_end, g);
+        range_start = range_end;
+      } while (range_start != IndexTargets.end());
+   }

    for (auto&& Target: IndexTargets)
    {
       // if we have seen a target which is created-by a target this one here is declared a
    for (auto&& Target: IndexTargets)
    {
       // if we have seen a target which is created-by a target this one here is declared a


@@ -1471,24 +1561,6 @@ void pkgAcqMetaClearSig::QueueIndexes(bool const verify)                 /*{{{*/
                                                                        /*}}}*/
 bool pkgAcqMetaBase::VerifyVendor(string const &)                      /*{{{*/
 {
                                                                        /*}}}*/
 bool pkgAcqMetaBase::VerifyVendor(string const &)                      /*{{{*/
 {

-   string Transformed = TransactionManager->MetaIndexParser->GetExpectedDist();
-
-   if (Transformed == "../project/experimental")
-   {
-      Transformed = "experimental";
-   }
-
-   auto pos = Transformed.rfind('/');
-   if (pos != string::npos)
-   {
-      Transformed = Transformed.substr(0, pos);
-   }
-
-   if (Transformed == ".")
-   {
-      Transformed = "";
-   }
-

    if (TransactionManager->MetaIndexParser->GetValidUntil() > 0)
    {
       time_t const invalid_since = time(NULL) - TransactionManager->MetaIndexParser->GetValidUntil();
    if (TransactionManager->MetaIndexParser->GetValidUntil() > 0)
    {
       time_t const invalid_since = time(NULL) - TransactionManager->MetaIndexParser->GetValidUntil();


@@ -1523,30 +1595,27 @@ bool pkgAcqMetaBase::VerifyVendor(string const &)                       /*{{{*/
       TransactionManager->LastMetaIndexParser = NULL;
    }
 
       TransactionManager->LastMetaIndexParser = NULL;
    }
 

-   if (_config->FindB("Debug::pkgAcquire::Auth", false)) 
+   if (_config->FindB("Debug::pkgAcquire::Auth", false))

    {
       std::cerr << "Got Codename: " << TransactionManager->MetaIndexParser->GetCodename() << std::endl;
    {
       std::cerr << "Got Codename: " << TransactionManager->MetaIndexParser->GetCodename() << std::endl;

+      std::cerr << "Got Suite: " << TransactionManager->MetaIndexParser->GetSuite() << std::endl;

       std::cerr << "Expecting Dist: " << TransactionManager->MetaIndexParser->GetExpectedDist() << std::endl;
       std::cerr << "Expecting Dist: " << TransactionManager->MetaIndexParser->GetExpectedDist() << std::endl;

-      std::cerr << "Transformed Dist: " << Transformed << std::endl;

    }
 
    }
 

-   if (TransactionManager->MetaIndexParser->CheckDist(Transformed) == false)
+   // One day that might become fatal…
+   auto const ExpectedDist = TransactionManager->MetaIndexParser->GetExpectedDist();
+   auto const NowCodename = TransactionManager->MetaIndexParser->GetCodename();
+   if (TransactionManager->MetaIndexParser->CheckDist(ExpectedDist) == false)
+      _error->Warning(_("Conflicting distribution: %s (expected %s but got %s)"),
+           Desc.Description.c_str(), ExpectedDist.c_str(), NowCodename.c_str());
+   // might be okay, might be not
+   if (TransactionManager->LastMetaIndexParser != nullptr)

    {
    {

-      // This might become fatal one day
-//       Status = StatAuthError;
-//       ErrorText = "Conflicting distribution; expected "
-//          + MetaIndexParser->GetExpectedDist() + " but got "
-//          + MetaIndexParser->GetCodename();
-//       return false;
-      if (!Transformed.empty())
-      {
-         _error->Warning(_("Conflicting distribution: %s (expected %s but got %s)"),
-                         Desc.Description.c_str(),
-                         Transformed.c_str(),
-                         TransactionManager->MetaIndexParser->GetCodename().c_str());
-      }
+      auto const LastCodename = TransactionManager->LastMetaIndexParser->GetCodename();
+      if (LastCodename.empty() == false && NowCodename.empty() == false && LastCodename != NowCodename)
+        _error->Warning(_("Conflicting distribution: %s (expected %s but got %s)"),
+              Desc.Description.c_str(), LastCodename.c_str(), NowCodename.c_str());

    }
    }

-

    return true;
 }
                                                                        /*}}}*/
    return true;
 }
                                                                        /*}}}*/


@@ -1838,10 +1907,16 @@ void pkgAcqMetaSig::Done(string const &Message, HashStringList const &Hashes,
    }
    else if(MetaIndex->CheckAuthDone(Message) == true)
    {
    }
    else if(MetaIndex->CheckAuthDone(Message) == true)
    {

-      if (TransactionManager->IMSHit == false)
+      auto const Releasegpg = GetFinalFilename();
+      auto const Release = MetaIndex->GetFinalFilename();
+      // if this is an IMS-Hit on Release ensure we also have the the Release.gpg file stored
+      // (previously an unknown pubkey) – but only if the Release file exists locally (unlikely
+      // event of InRelease removed from the mirror causing fallback but still an IMS-Hit)
+      if (TransactionManager->IMSHit == false ||
+           (FileExists(Releasegpg) == false && FileExists(Release) == true))

       {
       {

-        TransactionManager->TransactionStageCopy(this, DestFile, GetFinalFilename());
-        TransactionManager->TransactionStageCopy(MetaIndex, MetaIndex->DestFile, MetaIndex->GetFinalFilename());
+        TransactionManager->TransactionStageCopy(this, DestFile, Releasegpg);
+        TransactionManager->TransactionStageCopy(MetaIndex, MetaIndex->DestFile, Release);

       }
    }
    else if (MetaIndex->Status != StatAuthError)
       }
    }
    else if (MetaIndex->Status != StatAuthError)


@@ -1931,44 +2006,33 @@ pkgAcqBaseIndex::~pkgAcqBaseIndex() {}
 pkgAcqDiffIndex::pkgAcqDiffIndex(pkgAcquire * const Owner,
                                  pkgAcqMetaClearSig * const TransactionManager,
                                  IndexTarget const &Target)
 pkgAcqDiffIndex::pkgAcqDiffIndex(pkgAcquire * const Owner,
                                  pkgAcqMetaClearSig * const TransactionManager,
                                  IndexTarget const &Target)

-   : pkgAcqBaseIndex(Owner, TransactionManager, Target), d(NULL), diffs(NULL)
+   : pkgAcqIndex(Owner, TransactionManager, Target, true), d(NULL), diffs(NULL)

 {
    // FIXME: Magic number as an upper bound on pdiffs we will reasonably acquire
    ExpectedAdditionalItems = 40;
 {
    // FIXME: Magic number as an upper bound on pdiffs we will reasonably acquire
    ExpectedAdditionalItems = 40;

-

    Debug = _config->FindB("Debug::pkgAcquire::Diffs",false);
 
    Debug = _config->FindB("Debug::pkgAcquire::Diffs",false);
 

-   Desc.Owner = this;
-   Desc.Description = GetDiffIndexFileName(Target.Description);
-   Desc.ShortDesc = Target.ShortDesc;
-   Desc.URI = GetDiffIndexURI(Target);
-
-   DestFile = GetPartialFileNameFromURI(Desc.URI);
+   CompressionExtensions.clear();
+   {
+      std::vector<std::string> types = APT::Configuration::getCompressionTypes();
+      if (types.empty() == false)
+      {
+        std::ostringstream os;
+        std::copy_if(types.begin(), types.end()-1, std::ostream_iterator<std::string>(os, " "), [&](std::string const type) {
+              if (type == "uncompressed")
+                 return true;
+              return TransactionManager->MetaIndexParser->Exists(GetDiffIndexFileName(Target.MetaKey) + '.' + type);
+        });
+        os << *types.rbegin();
+        CompressionExtensions = os.str();
+      }
+   }
+   if (Target.Option(IndexTarget::COMPRESSIONTYPES).find("by-hash") != std::string::npos)
+      CompressionExtensions = "by-hash " + CompressionExtensions;
+   Init(GetDiffIndexURI(Target), GetDiffIndexFileName(Target.Description), Target.ShortDesc);

 
    if(Debug)
       std::clog << "pkgAcqDiffIndex: " << Desc.URI << std::endl;
 
    if(Debug)
       std::clog << "pkgAcqDiffIndex: " << Desc.URI << std::endl;

-
-   QueueURI(Desc);
-}
-                                                                       /*}}}*/
-// AcqIndex::Custom600Headers - Insert custom request headers          /*{{{*/
-// ---------------------------------------------------------------------
-/* The only header we use is the last-modified header. */
-string pkgAcqDiffIndex::Custom600Headers() const
-{
-   if (TransactionManager->LastMetaIndexParser != NULL)
-      return "\nIndex-File: true";
-
-   string const Final = GetFinalFilename();
-
-   if(Debug)
-      std::clog << "Custom600Header-IMS: " << Final << std::endl;
-
-   struct stat Buf;
-   if (stat(Final.c_str(),&Buf) != 0)
-      return "\nIndex-File: true";
-   
-   return "\nIndex-File: true\nLast-Modified: " + TimeRFC1123(Buf.st_mtime, false);

 }
                                                                        /*}}}*/
 void pkgAcqDiffIndex::QueueOnIMSHit() const                            /*{{{*/
 }
                                                                        /*}}}*/
 void pkgAcqDiffIndex::QueueOnIMSHit() const                            /*{{{*/


@@ -1999,7 +2063,7 @@ bool pkgAcqDiffIndex::ParseDiffIndex(string const &IndexDiffFile) /*{{{*/
       std::clog << "pkgAcqDiffIndex::ParseIndexDiff() " << IndexDiffFile
         << std::endl;
 
       std::clog << "pkgAcqDiffIndex::ParseIndexDiff() " << IndexDiffFile
         << std::endl;
 

-   FileFd Fd(IndexDiffFile,FileFd::ReadOnly);
+   FileFd Fd(IndexDiffFile, FileFd::ReadOnly, FileFd::Extension);

    pkgTagFile TF(&Fd);
    if (Fd.IsOpen() == false || Fd.Failed())
       return false;
    pkgTagFile TF(&Fd);
    if (Fd.IsOpen() == false || Fd.Failed())
       return false;


@@ -2011,7 +2075,7 @@ bool pkgAcqDiffIndex::ParseDiffIndex(string const &IndexDiffFile) /*{{{*/
    HashStringList ServerHashes;
    unsigned long long ServerSize = 0;
 
    HashStringList ServerHashes;
    unsigned long long ServerSize = 0;
 

-   auto const &posix = std::locale("C.UTF-8");
+   auto const &posix = std::locale::classic();

    for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type)
    {
       std::string tagname = *type;
    for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type)
    {
       std::string tagname = *type;


@@ -2371,7 +2435,9 @@ bool pkgAcqDiffIndex::ParseDiffIndex(string const &IndexDiffFile) /*{{{*/
                                                                        /*}}}*/
 void pkgAcqDiffIndex::Failed(string const &Message,pkgAcquire::MethodConfig const * const Cnf)/*{{{*/
 {
                                                                        /*}}}*/
 void pkgAcqDiffIndex::Failed(string const &Message,pkgAcquire::MethodConfig const * const Cnf)/*{{{*/
 {

-   pkgAcqBaseIndex::Failed(Message,Cnf);
+   if (CommonFailed(GetDiffIndexURI(Target), GetDiffIndexFileName(Target.Description), Message, Cnf))
+      return;
+

    Status = StatDone;
    ExpectedAdditionalItems = 0;
 
    Status = StatDone;
    ExpectedAdditionalItems = 0;
 


@@ -2789,10 +2855,12 @@ pkgAcqIndexMergeDiffs::~pkgAcqIndexMergeDiffs() {}
 // AcqIndex::AcqIndex - Constructor                                    /*{{{*/
 pkgAcqIndex::pkgAcqIndex(pkgAcquire * const Owner,
                          pkgAcqMetaClearSig * const TransactionManager,
 // AcqIndex::AcqIndex - Constructor                                    /*{{{*/
 pkgAcqIndex::pkgAcqIndex(pkgAcquire * const Owner,
                          pkgAcqMetaClearSig * const TransactionManager,

-                         IndexTarget const &Target)
+                         IndexTarget const &Target, bool const Derived)

    : pkgAcqBaseIndex(Owner, TransactionManager, Target), d(NULL), Stage(STAGE_DOWNLOAD),
    CompressionExtensions(Target.Option(IndexTarget::COMPRESSIONTYPES))
 {
    : pkgAcqBaseIndex(Owner, TransactionManager, Target), d(NULL), Stage(STAGE_DOWNLOAD),
    CompressionExtensions(Target.Option(IndexTarget::COMPRESSIONTYPES))
 {

+   if (Derived)
+      return;

    Init(Target.URI, Target.Description, Target.ShortDesc);
 
    if(_config->FindB("Debug::Acquire::Transaction", false) == true)
    Init(Target.URI, Target.Description, Target.ShortDesc);
 
    if(_config->FindB("Debug::Acquire::Transaction", false) == true)


@@ -2825,10 +2893,6 @@ void pkgAcqIndex::Init(string const &URI, string const &URIDesc,
    DestFile = GetPartialFileNameFromURI(URI);
    NextCompressionExtension(CurrentCompressionExtension, CompressionExtensions, false);
 
    DestFile = GetPartialFileNameFromURI(URI);
    NextCompressionExtension(CurrentCompressionExtension, CompressionExtensions, false);
 

-   // store file size of the download to ensure the fetcher gives
-   // accurate progress reporting
-   FileSize = GetExpectedHashes().FileSize();
-

    if (CurrentCompressionExtension == "uncompressed")
    {
       Desc.URI = URI;
    if (CurrentCompressionExtension == "uncompressed")
    {
       Desc.URI = URI;


@@ -2843,6 +2907,8 @@ void pkgAcqIndex::Init(string const &URI, string const &URIDesc,
         Desc.URI = URI + '.' + CurrentCompressionExtension;
         DestFile = DestFile + '.' + CurrentCompressionExtension;
       }
         Desc.URI = URI + '.' + CurrentCompressionExtension;
         DestFile = DestFile + '.' + CurrentCompressionExtension;
       }

+      else
+        Desc.URI = URI;

 
       HashStringList const Hashes = GetExpectedHashes();
       HashString const * const TargetHash = Hashes.find(NULL);
 
       HashStringList const Hashes = GetExpectedHashes();
       HashString const * const TargetHash = Hashes.find(NULL);


@@ -2865,6 +2931,9 @@ void pkgAcqIndex::Init(string const &URI, string const &URIDesc,
       DestFile = DestFile + '.' + CurrentCompressionExtension;
    }
 
       DestFile = DestFile + '.' + CurrentCompressionExtension;
    }
 

+   // store file size of the download to ensure the fetcher gives
+   // accurate progress reporting
+   FileSize = GetExpectedHashes().FileSize();

 
    Desc.Description = URIDesc;
    Desc.Owner = this;
 
    Desc.Description = URIDesc;
    Desc.Owner = this;


@@ -2897,20 +2966,40 @@ string pkgAcqIndex::Custom600Headers() const
 }
                                                                        /*}}}*/
 // AcqIndex::Failed - getting the indexfile failed                     /*{{{*/
 }
                                                                        /*}}}*/
 // AcqIndex::Failed - getting the indexfile failed                     /*{{{*/

-void pkgAcqIndex::Failed(string const &Message,pkgAcquire::MethodConfig const * const Cnf)
+bool pkgAcqIndex::CommonFailed(std::string const &TargetURI, std::string const TargetDesc,
+      std::string const &Message, pkgAcquire::MethodConfig const * const Cnf)

 {
    pkgAcqBaseIndex::Failed(Message,Cnf);
 
 {
    pkgAcqBaseIndex::Failed(Message,Cnf);
 

+   if (UsedMirror.empty() == false && UsedMirror != "DIRECT" &&
+        LookupTag(Message, "FailReason") == "HttpError404")
+   {
+      UsedMirror = "DIRECT";
+      if (Desc.URI.find("/by-hash/") != std::string::npos)
+        CompressionExtensions = "by-hash " + CompressionExtensions;
+      else
+        CompressionExtensions = CurrentCompressionExtension + ' ' + CompressionExtensions;
+      Init(TargetURI, TargetDesc, Desc.ShortDesc);
+      Status = StatIdle;
+      return true;
+   }
+

    // authorisation matches will not be fixed by other compression types
    if (Status != StatAuthError)
    {
       if (CompressionExtensions.empty() == false)
       {
    // authorisation matches will not be fixed by other compression types
    if (Status != StatAuthError)
    {
       if (CompressionExtensions.empty() == false)
       {

-        Init(Target.URI, Desc.Description, Desc.ShortDesc);
+        Init(TargetURI, Desc.Description, Desc.ShortDesc);

         Status = StatIdle;
         Status = StatIdle;

-        return;
+        return true;

       }
    }
       }
    }

+   return false;
+}
+void pkgAcqIndex::Failed(string const &Message,pkgAcquire::MethodConfig const * const Cnf)
+{
+   if (CommonFailed(Target.URI, Target.Description, Message, Cnf))
+      return;

 
    if(Target.IsOptional && GetExpectedHashes().empty() && Stage == STAGE_DOWNLOAD)
       Status = StatDone;
 
    if(Target.IsOptional && GetExpectedHashes().empty() && Stage == STAGE_DOWNLOAD)
       Status = StatDone;


@@ -3218,9 +3307,8 @@ bool pkgAcqArchive::QueueNext()
 
       // Create the item
       Local = false;
 
       // Create the item
       Local = false;

-      QueueURI(Desc);
-

       ++Vf;
       ++Vf;

+      QueueURI(Desc);

       return true;
    }
    return false;
       return true;
    }
    return false;


@@ -3379,7 +3467,7 @@ void pkgAcqChangelog::Init(std::string const &DestDir, std::string const &DestFi
    TemporaryDirectory = tmpname;
 
    ChangeOwnerAndPermissionOfFile("Item::QueueURI", TemporaryDirectory.c_str(),
    TemporaryDirectory = tmpname;
 
    ChangeOwnerAndPermissionOfFile("Item::QueueURI", TemporaryDirectory.c_str(),

-        SandboxUser.c_str(), "root", 0700);
+        SandboxUser.c_str(), ROOT_GROUP, 0700);

 
    DestFile = flCombine(TemporaryDirectory, DestFileName);
    if (DestDir.empty() == false)
 
    DestFile = flCombine(TemporaryDirectory, DestFileName);
    if (DestDir.empty() == false)


@@ -3427,7 +3515,8 @@ std::string pkgAcqChangelog::URI(pkgCache::VerIterator const &Ver)        /*{{{*/
       pkgCache::PkgIterator const Pkg = Ver.ParentPkg();
       if (Pkg->CurrentVer != 0 && Pkg.CurrentVer() == Ver)
       {
       pkgCache::PkgIterator const Pkg = Ver.ParentPkg();
       if (Pkg->CurrentVer != 0 && Pkg.CurrentVer() == Ver)
       {

-        std::string const basename = std::string("/usr/share/doc/") + Pkg.Name() + "/changelog";
+        std::string const root = _config->FindDir("Dir");
+        std::string const basename = root + std::string("usr/share/doc/") + Pkg.Name() + "/changelog";

         std::string const debianname = basename + ".Debian";
         if (FileExists(debianname))
            return "copy://" + debianname;
         std::string const debianname = basename + ".Debian";
         if (FileExists(debianname))
            return "copy://" + debianname;