allow methods to be disabled and redirected via config

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

diff --git a/apt-pkg/acquire-worker.cc b/apt-pkg/acquire-worker.cc
index 64df3c80fe13456734c86ea1e5d94f1fd6f141a8..7a4f8177fa609eaa9ef3a14d0a13f2ffee5c547d 100644 (file)
--- a/apt-pkg/acquire-worker.cc
+++ b/apt-pkg/acquire-worker.cc
@@ -23,10 +23,10 @@
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/hashes.h>
 
 #include <apt-pkg/strutl.h>
 #include <apt-pkg/hashes.h>
 

+#include <algorithm>

 #include <string>
 #include <vector>
 #include <iostream>
 #include <string>
 #include <vector>
 #include <iostream>

-#include <sstream>

 
 #include <sys/stat.h>
 #include <stdlib.h>
 
 #include <sys/stat.h>
 #include <stdlib.h>


@@ -34,6 +34,7 @@
 #include <signal.h>
 #include <stdio.h>
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
 #include <errno.h>

+#include <sstream>

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


@@ -41,34 +42,16 @@
 using namespace std;
 
 // Worker::Worker - Constructor for Queue startup                      /*{{{*/
 using namespace std;
 
 // Worker::Worker - Constructor for Queue startup                      /*{{{*/

-// ---------------------------------------------------------------------
-/* */
-pkgAcquire::Worker::Worker(Queue *Q,MethodConfig *Cnf,
-                          pkgAcquireStatus *Log) : Log(Log)
+pkgAcquire::Worker::Worker(Queue *Q, MethodConfig *Cnf, pkgAcquireStatus *log) :
+   d(NULL), OwnerQ(Q), Log(log), Config(Cnf), Access(Cnf->Access),
+   CurrentItem(nullptr), CurrentSize(0), TotalSize(0)

 {
 {

-   OwnerQ = Q;
-   Config = Cnf;
-   Access = Cnf->Access;
-   CurrentItem = 0;
-   TotalSize = 0;
-   CurrentSize = 0;
-   
-   Construct();   
+   Construct();

 }
                                                                        /*}}}*/
 // Worker::Worker - Constructor for method config startup              /*{{{*/
 }
                                                                        /*}}}*/
 // Worker::Worker - Constructor for method config startup              /*{{{*/

-// ---------------------------------------------------------------------
-/* */
-pkgAcquire::Worker::Worker(MethodConfig *Cnf)
+pkgAcquire::Worker::Worker(MethodConfig *Cnf) : Worker(nullptr, Cnf, nullptr)

 {
 {

-   OwnerQ = 0;
-   Config = Cnf;
-   Access = Cnf->Access;
-   CurrentItem = 0;
-   TotalSize = 0;
-   CurrentSize = 0;
-   
-   Construct();   

 }
                                                                        /*}}}*/
 // Worker::Construct - Constructor helper                              /*{{{*/
 }
                                                                        /*}}}*/
 // Worker::Construct - Constructor helper                              /*{{{*/


@@ -110,17 +93,38 @@ pkgAcquire::Worker::~Worker()
 bool pkgAcquire::Worker::Start()
 {
    // Get the method path
 bool pkgAcquire::Worker::Start()
 {
    // Get the method path

-   string Method = _config->FindDir("Dir::Bin::Methods") + Access;
+   constexpr char const * const methodsDir = "Dir::Bin::Methods";
+   std::string const confItem = std::string(methodsDir) + "::" + Access;
+   std::string Method;
+   if (_config->Exists(confItem))
+        Method = _config->FindFile(confItem.c_str());
+   else
+        Method = _config->FindDir(methodsDir) + Access;

    if (FileExists(Method) == false)
    {
    if (FileExists(Method) == false)
    {

+      if (flNotDir(Method) == "false")
+      {
+        _error->Error(_("The method '%s' is explicitly disabled via configuration."), Access.c_str());
+        if (Access == "http" || Access == "https")
+           _error->Notice(_("If you meant to use Tor remember to use %s instead of %s."), ("tor+" + Access).c_str(), Access.c_str());
+        return false;
+      }

       _error->Error(_("The method driver %s could not be found."),Method.c_str());
       _error->Error(_("The method driver %s could not be found."),Method.c_str());

-      if (Access == "https")
-        _error->Notice(_("Is the package %s installed?"), "apt-transport-https");
+      std::string const A(Access.cbegin(), std::find(Access.cbegin(), Access.cend(), '+'));
+      std::string pkg;
+      strprintf(pkg, "apt-transport-%s", A.c_str());
+      _error->Notice(_("Is the package %s installed?"), pkg.c_str());

       return false;
    }
       return false;
    }

+   std::string const Calling = _config->FindDir(methodsDir) + Access;

 
    if (Debug == true)
 
    if (Debug == true)

-      clog << "Starting method '" << Method << '\'' << endl;
+   {
+      std::clog << "Starting method '" << Calling << "'";
+      if (Calling != Method)
+        std::clog << " ( via " << Method << " )";
+      std::clog << endl;
+   }

 
    // Create the pipes
    int Pipes[4] = {-1,-1,-1,-1};
 
    // Create the pipes
    int Pipes[4] = {-1,-1,-1,-1};


@@ -133,7 +137,7 @@ bool pkgAcquire::Worker::Start()
    }
    for (int I = 0; I != 4; I++)
       SetCloseExec(Pipes[I],true);
    }
    for (int I = 0; I != 4; I++)
       SetCloseExec(Pipes[I],true);

-   
+

    // Fork off the process
    Process = ExecFork();
    if (Process == 0)
    // Fork off the process
    Process = ExecFork();
    if (Process == 0)


@@ -142,14 +146,12 @@ bool pkgAcquire::Worker::Start()
       dup2(Pipes[1],STDOUT_FILENO);
       dup2(Pipes[2],STDIN_FILENO);
       SetCloseExec(STDOUT_FILENO,false);
       dup2(Pipes[1],STDOUT_FILENO);
       dup2(Pipes[2],STDIN_FILENO);
       SetCloseExec(STDOUT_FILENO,false);

-      SetCloseExec(STDIN_FILENO,false);      
+      SetCloseExec(STDIN_FILENO,false);

       SetCloseExec(STDERR_FILENO,false);
       SetCloseExec(STDERR_FILENO,false);

-      
-      const char *Args[2];
-      Args[0] = Method.c_str();
-      Args[1] = 0;
-      execv(Args[0],(char **)Args);
-      cerr << "Failed to exec method " << Args[0] << endl;
+
+      const char * const Args[] = { Calling.c_str(), nullptr };
+      execv(Method.c_str() ,const_cast<char **>(Args));
+      std::cerr << "Failed to exec method " << Calling << " ( via " << Method << ")" << endl;

       _exit(100);
    }
 
       _exit(100);
    }
 


@@ -162,7 +164,7 @@ bool pkgAcquire::Worker::Start()
    close(Pipes[2]);
    OutReady = false;
    InReady = true;
    close(Pipes[2]);
    OutReady = false;
    InReady = true;

-   
+

    // Read the configuration data
    if (WaitFd(InFd) == false ||
        ReadMessages() == false)
    // Read the configuration data
    if (WaitFd(InFd) == false ||
        ReadMessages() == false)


@@ -171,7 +173,7 @@ bool pkgAcquire::Worker::Start()
    RunMessages();
    if (OwnerQ != 0)
       SendConfiguration();
    RunMessages();
    if (OwnerQ != 0)
       SendConfiguration();

-   
+

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


@@ -189,6 +191,25 @@ bool pkgAcquire::Worker::ReadMessages()
 // ---------------------------------------------------------------------
 /* This takes the messages from the message queue and runs them through
    the parsers in order. */
 // ---------------------------------------------------------------------
 /* This takes the messages from the message queue and runs them through
    the parsers in order. */

+enum class APT_HIDDEN MessageType {
+   CAPABILITIES = 100,
+   LOG = 101,
+   STATUS = 102,
+   REDIRECT = 103,
+   WARNING = 104,
+   URI_START = 200,
+   URI_DONE = 201,
+   URI_FAILURE = 400,
+   GENERAL_FAILURE = 401,
+   MEDIA_CHANGE = 403
+};
+static bool isDoomedItem(pkgAcquire::Item const * const Itm)
+{
+   auto const TransItm = dynamic_cast<pkgAcqTransactionItem const * const>(Itm);
+   if (TransItm == nullptr)
+      return false;
+   return TransItm->TransactionManager->State != pkgAcqTransactionItem::TransactionStarted;
+}

 bool pkgAcquire::Worker::RunMessages()
 {
    while (MessageQueue.empty() == false)
 bool pkgAcquire::Worker::RunMessages()
 {
    while (MessageQueue.empty() == false)


@@ -198,218 +219,330 @@ bool pkgAcquire::Worker::RunMessages()
 
       if (Debug == true)
         clog << " <- " << Access << ':' << QuoteString(Message,"\n") << endl;
 
       if (Debug == true)
         clog << " <- " << Access << ':' << QuoteString(Message,"\n") << endl;

-      
+

       // Fetch the message number
       char *End;
       // Fetch the message number
       char *End;

-      int Number = strtol(Message.c_str(),&End,10);
+      MessageType const Number = static_cast<MessageType>(strtoul(Message.c_str(),&End,10));

       if (End == Message.c_str())
         return _error->Error("Invalid message from method %s: %s",Access.c_str(),Message.c_str());
 
       string URI = LookupTag(Message,"URI");
       if (End == Message.c_str())
         return _error->Error("Invalid message from method %s: %s",Access.c_str(),Message.c_str());
 
       string URI = LookupTag(Message,"URI");

-      pkgAcquire::Queue::QItem *Itm = 0;
+      pkgAcquire::Queue::QItem *Itm = NULL;

       if (URI.empty() == false)
         Itm = OwnerQ->FindItem(URI,this);
 
       if (URI.empty() == false)
         Itm = OwnerQ->FindItem(URI,this);
 

-      // update used mirror
-      string UsedMirror = LookupTag(Message,"UsedMirror", "");
-      if (!UsedMirror.empty() && 
-          Itm && 
-          Itm->Description.find(" ") != string::npos) 
+      if (Itm != NULL)

       {
       {

-         Itm->Description.replace(0, Itm->Description.find(" "), UsedMirror);
-         // FIXME: will we need this as well?
-         //Itm->ShortDesc = UsedMirror;
+        // update used mirror
+        string UsedMirror = LookupTag(Message,"UsedMirror", "");
+        if (UsedMirror.empty() == false)
+        {
+           for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+              (*O)->UsedMirror = UsedMirror;
+
+           if (Itm->Description.find(" ") != string::npos)
+              Itm->Description.replace(0, Itm->Description.find(" "), UsedMirror);
+        }

       }
       }

-      
+

       // Determine the message number and dispatch
       switch (Number)
       {
       // Determine the message number and dispatch
       switch (Number)
       {

-        // 100 Capabilities
-        case 100:
+        case MessageType::CAPABILITIES:

         if (Capabilities(Message) == false)
            return _error->Error("Unable to process Capabilities message from %s",Access.c_str());
         break;
         if (Capabilities(Message) == false)
            return _error->Error("Unable to process Capabilities message from %s",Access.c_str());
         break;

-        
-        // 101 Log
-        case 101:
+
+        case MessageType::LOG:

         if (Debug == true)
            clog << " <- (log) " << LookupTag(Message,"Message") << endl;
         break;
         if (Debug == true)
            clog << " <- (log) " << LookupTag(Message,"Message") << endl;
         break;

-        
-        // 102 Status
-        case 102:
+
+        case MessageType::STATUS:

         Status = LookupTag(Message,"Message");
         break;
         Status = LookupTag(Message,"Message");
         break;

-           
-         // 103 Redirect
-         case 103:
+
+        case MessageType::REDIRECT:

          {
          {

-            if (Itm == 0)
+            if (Itm == nullptr)

             {
                _error->Error("Method gave invalid 103 Redirect message");
                break;
             }
             {
                _error->Error("Method gave invalid 103 Redirect message");
                break;
             }

- 
-            string NewURI = LookupTag(Message,"New-URI",URI.c_str());
+
+           std::string const NewURI = LookupTag(Message,"New-URI",URI.c_str());

             Itm->URI = NewURI;
 
            ItemDone();
 
             Itm->URI = NewURI;
 
            ItemDone();
 

-           pkgAcquire::Item *Owner = Itm->Owner;
-           pkgAcquire::ItemDesc Desc = *Itm;
-

            // Change the status so that it can be dequeued
            // Change the status so that it can be dequeued

-           Owner->Status = pkgAcquire::Item::StatIdle;
+           for (auto const &O: Itm->Owners)
+              O->Status = pkgAcquire::Item::StatIdle;

            // Mark the item as done (taking care of all queues)
            // and then put it in the main queue again
            // Mark the item as done (taking care of all queues)
            // and then put it in the main queue again

+           std::vector<Item*> const ItmOwners = Itm->Owners;

            OwnerQ->ItemDone(Itm);
            OwnerQ->ItemDone(Itm);

-           OwnerQ->Owner->Enqueue(Desc);
-
-           if (Log != 0)
-              Log->Done(Desc);
+           Itm = nullptr;
+           for (auto const &Owner: ItmOwners)
+           {
+              pkgAcquire::ItemDesc &desc = Owner->GetItemDesc();
+              if (Owner->IsRedirectionLoop(NewURI))
+              {
+                 std::string msg = Message;
+                 msg.append("\nFailReason: RedirectionLoop");
+                 Owner->Failed(msg, Config);
+                 if (Log != nullptr)
+                    Log->Fail(Owner->GetItemDesc());
+                 continue;
+              }
+
+              if (Log != nullptr)
+                 Log->Done(desc);
+
+              // if we change site, treat it as a mirror change
+              if (URI::SiteOnly(NewURI) != URI::SiteOnly(desc.URI))
+              {
+                 auto const firstSpace = desc.Description.find(" ");
+                 if (firstSpace != std::string::npos)
+                 {
+                    std::string const OldSite = desc.Description.substr(0, firstSpace);
+                    if (likely(APT::String::Startswith(desc.URI, OldSite)))
+                    {
+                       std::string const OldExtra = desc.URI.substr(OldSite.length() + 1);
+                       if (likely(APT::String::Endswith(NewURI, OldExtra)))
+                       {
+                          std::string const NewSite = NewURI.substr(0, NewURI.length() - OldExtra.length());
+                          Owner->UsedMirror = URI::ArchiveOnly(NewSite);
+                          desc.Description.replace(0, firstSpace, Owner->UsedMirror);
+                       }
+                    }
+                 }
+              }
+              desc.URI = NewURI;
+              if (isDoomedItem(Owner) == false)
+                 OwnerQ->Owner->Enqueue(desc);
+           }

             break;
          }
             break;
          }

-   
-        // 200 URI Start
-        case 200:
+
+        case MessageType::WARNING:
+           _error->Warning("%s: %s", Itm->Owner->DescURI().c_str(), LookupTag(Message,"Message").c_str());
+           break;
+
+        case MessageType::URI_START:

         {
         {

-           if (Itm == 0)
+           if (Itm == nullptr)

            {
               _error->Error("Method gave invalid 200 URI Start message");
               break;
            }
            {
               _error->Error("Method gave invalid 200 URI Start message");
               break;
            }

-           
+

            CurrentItem = Itm;
            CurrentSize = 0;
            TotalSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
            ResumePoint = strtoull(LookupTag(Message,"Resume-Point","0").c_str(), NULL, 10);
            CurrentItem = Itm;
            CurrentSize = 0;
            TotalSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
            ResumePoint = strtoull(LookupTag(Message,"Resume-Point","0").c_str(), NULL, 10);

-           Itm->Owner->Start(Message,strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10));
-
-           // Display update before completion
-           if (Log != 0 && Log->MorePulses == true)
-              Log->Pulse(Itm->Owner->GetOwner());
-           
-           if (Log != 0)
-              Log->Fetch(*Itm);
+           for (auto const Owner: Itm->Owners)
+           {
+              Owner->Start(Message, TotalSize);
+              // Display update before completion
+              if (Log != nullptr)
+              {
+                 if (Log->MorePulses == true)
+                    Log->Pulse(Owner->GetOwner());
+                 Log->Fetch(Owner->GetItemDesc());
+              }
+           }

 
            break;
         }
 
            break;
         }

-        
-        // 201 URI Done
-        case 201:
+
+        case MessageType::URI_DONE:

         {
         {

-           if (Itm == 0)
+           if (Itm == nullptr)

            {
               _error->Error("Method gave invalid 201 URI Done message");
               break;
            }
            {
               _error->Error("Method gave invalid 201 URI Done message");
               break;
            }

-           
-           pkgAcquire::Item *Owner = Itm->Owner;
-           pkgAcquire::ItemDesc Desc = *Itm;
-           
+
+           PrepareFiles("201::URIDone", Itm);
+

            // Display update before completion
            if (Log != 0 && Log->MorePulses == true)
            // Display update before completion
            if (Log != 0 && Log->MorePulses == true)

-              Log->Pulse(Owner->GetOwner());
-           
-           OwnerQ->ItemDone(Itm);
-           unsigned long long const ServerSize = strtoull(LookupTag(Message,"Size","0").c_str(), NULL, 10);
-            bool isHit = StringToBool(LookupTag(Message,"IMS-Hit"),false) ||
-                         StringToBool(LookupTag(Message,"Alt-IMS-Hit"),false);
-            // Using the https method the server might return 200, but the
-            // If-Modified-Since condition is not satsified, libcurl will
-            // discard the download. In this case, however, TotalSize will be
-            // set to the actual size of the file, while ServerSize will be set
-            // to 0. Therefore, if the item is marked as a hit and the
-            // downloaded size (ServerSize) is 0, we ignore TotalSize.
-           if (TotalSize != 0 && (!isHit || ServerSize != 0) && ServerSize != TotalSize)
-              _error->Warning("Size of file %s is not what the server reported %s %llu",
-                              Owner->DestFile.c_str(), LookupTag(Message,"Size","0").c_str(),TotalSize);
-
-           // see if there is a hash to verify
-           HashStringList RecivedHashes;
-           HashStringList expectedHashes = Owner->HashSums();
-           for (HashStringList::const_iterator hs = expectedHashes.begin(); hs != expectedHashes.end(); ++hs)
-           {
-              std::string const tagname = hs->HashType() + "-Hash";
-              std::string const hashsum = LookupTag(Message, tagname.c_str());
-              if (hashsum.empty() == false)
-                 RecivedHashes.push_back(HashString(hs->HashType(), hashsum));
-           }
+              for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+                 Log->Pulse((*O)->GetOwner());

 
 

-           if(_config->FindB("Debug::pkgAcquire::Auth", false) == true)
+           HashStringList ReceivedHashes;

            {
            {

-              std::clog << "201 URI Done: " << Owner->DescURI() << endl
-                 << "RecivedHash:" << endl;
-              for (HashStringList::const_iterator hs = RecivedHashes.begin(); hs != RecivedHashes.end(); ++hs)
-                 std::clog <<  "\t- " << hs->toStr() << std::endl;
-              std::clog << "ExpectedHash:" << endl;
-              for (HashStringList::const_iterator hs = expectedHashes.begin(); hs != expectedHashes.end(); ++hs)
-                 std::clog <<  "\t- " << hs->toStr() << std::endl;
-              std::clog << endl;
+              std::string const givenfilename = LookupTag(Message, "Filename");
+              std::string const filename = givenfilename.empty() ? Itm->Owner->DestFile : givenfilename;
+              // see if we got hashes to verify
+              for (char const * const * type = HashString::SupportedHashes(); *type != NULL; ++type)
+              {
+                 std::string const tagname = std::string(*type) + "-Hash";
+                 std::string const hashsum = LookupTag(Message, tagname.c_str());
+                 if (hashsum.empty() == false)
+                    ReceivedHashes.push_back(HashString(*type, hashsum));
+              }
+              // not all methods always sent Hashes our way
+              if (ReceivedHashes.usable() == false)
+              {
+                 HashStringList const ExpectedHashes = Itm->GetExpectedHashes();
+                 if (ExpectedHashes.usable() == true && RealFileExists(filename))
+                 {
+                    Hashes calc(ExpectedHashes);
+                    FileFd file(filename, FileFd::ReadOnly, FileFd::None);
+                    calc.AddFD(file);
+                    ReceivedHashes = calc.GetHashStringList();
+                 }
+              }
+
+              // only local files can refer other filenames and counting them as fetched would be unfair
+              if (Log != NULL && Itm->Owner->Complete == false && Itm->Owner->Local == false && givenfilename == filename)
+                 Log->Fetched(ReceivedHashes.FileSize(),atoi(LookupTag(Message,"Resume-Point","0").c_str()));

            }
            }

-           Owner->Done(Message, ServerSize, RecivedHashes, Config);
-           ItemDone();

 
 

-           // Log that we are done
-           if (Log != 0)
+           std::vector<Item*> const ItmOwners = Itm->Owners;
+           OwnerQ->ItemDone(Itm);
+           Itm = NULL;
+
+           bool const isIMSHit = StringToBool(LookupTag(Message,"IMS-Hit"),false) ||
+              StringToBool(LookupTag(Message,"Alt-IMS-Hit"),false);
+           auto const forcedHash = _config->Find("Acquire::ForceHash");
+           for (auto const Owner: ItmOwners)

            {
            {

-              if (isHit)
+              HashStringList const ExpectedHashes = Owner->GetExpectedHashes();
+              if(_config->FindB("Debug::pkgAcquire::Auth", false) == true)
+              {
+                 std::clog << "201 URI Done: " << Owner->DescURI() << endl
+                    << "ReceivedHash:" << endl;
+                 for (HashStringList::const_iterator hs = ReceivedHashes.begin(); hs != ReceivedHashes.end(); ++hs)
+                    std::clog <<  "\t- " << hs->toStr() << std::endl;
+                 std::clog << "ExpectedHash:" << endl;
+                 for (HashStringList::const_iterator hs = ExpectedHashes.begin(); hs != ExpectedHashes.end(); ++hs)
+                    std::clog <<  "\t- " << hs->toStr() << std::endl;
+                 std::clog << endl;
+              }
+
+              // decide if what we got is what we expected
+              bool consideredOkay = false;
+              if ((forcedHash.empty() && ExpectedHashes.empty() == false) ||
+                    (forcedHash.empty() == false && ExpectedHashes.usable()))
+              {
+                 if (ReceivedHashes.empty())
+                 {
+                    /* IMS-Hits can't be checked here as we will have uncompressed file,
+                       but the hashes for the compressed file. What we have was good through
+                       so all we have to ensure later is that we are not stalled. */
+                    consideredOkay = isIMSHit;
+                 }
+                 else if (ReceivedHashes == ExpectedHashes)
+                    consideredOkay = true;
+                 else
+                    consideredOkay = false;
+
+              }
+              else
+                 consideredOkay = !Owner->HashesRequired();
+
+              if (consideredOkay == true)
+                 consideredOkay = Owner->VerifyDone(Message, Config);
+              else // hashsum mismatch
+                 Owner->Status = pkgAcquire::Item::StatAuthError;
+
+
+              if (consideredOkay == true)

               {
               {

-                 /* Hide 'hits' for local only sources - we also manage to
-                    hide gets */
-                 if (Config->LocalOnly == false)
-                    Log->IMSHit(Desc);
-              }               
+                 if (isDoomedItem(Owner) == false)
+                    Owner->Done(Message, ReceivedHashes, Config);
+                 if (Log != nullptr)
+                 {
+                    if (isIMSHit)
+                       Log->IMSHit(Owner->GetItemDesc());
+                    else
+                       Log->Done(Owner->GetItemDesc());
+                 }
+              }

               else
               else

-                 Log->Done(Desc);
+              {
+                 if (isDoomedItem(Owner) == false)
+                 {
+                    if (Message.find("\nFailReason:") == std::string::npos)
+                    {
+                       if (ReceivedHashes != ExpectedHashes)
+                          Message.append("\nFailReason: HashSumMismatch");
+                       else
+                          Message.append("\nFailReason: WeakHashSums");
+                    }
+                    Owner->Failed(Message,Config);
+                 }
+                 if (Log != nullptr)
+                    Log->Fail(Owner->GetItemDesc());
+              }

            }
            }

+           ItemDone();

            break;
            break;

-        }       
-        
-        // 400 URI Failure
-        case 400:
+        }
+
+        case MessageType::URI_FAILURE:

         {
         {

-           if (Itm == 0)
+           if (Itm == nullptr)

            {
               std::string const msg = LookupTag(Message,"Message");
               _error->Error("Method gave invalid 400 URI Failure message: %s", msg.c_str());
               break;
            }
 
            {
               std::string const msg = LookupTag(Message,"Message");
               _error->Error("Method gave invalid 400 URI Failure message: %s", msg.c_str());
               break;
            }
 

+           PrepareFiles("400::URIFailure", Itm);
+

            // Display update before completion
            // Display update before completion

-           if (Log != 0 && Log->MorePulses == true)
-              Log->Pulse(Itm->Owner->GetOwner());
-           
-           pkgAcquire::Item *Owner = Itm->Owner;
-           pkgAcquire::ItemDesc Desc = *Itm;
+           if (Log != nullptr && Log->MorePulses == true)
+              for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+                 Log->Pulse((*O)->GetOwner());
+
+           std::vector<Item*> const ItmOwners = Itm->Owners;

            OwnerQ->ItemDone(Itm);
            OwnerQ->ItemDone(Itm);

+           Itm = nullptr;

 
 

-           // set some status
-           if(LookupTag(Message,"FailReason") == "Timeout" || 
-              LookupTag(Message,"FailReason") == "TmpResolveFailure" ||
-              LookupTag(Message,"FailReason") == "ResolveFailure" ||
-              LookupTag(Message,"FailReason") == "ConnectionRefused") 
-              Owner->Status = pkgAcquire::Item::StatTransientNetworkError;
+           bool errTransient = false, errAuthErr = false;
+           {
+              std::string const failReason = LookupTag(Message, "FailReason");
+              {
+                 auto const reasons = { "Timeout", "ConnectionRefused",
+                    "ConnectionTimedOut", "ResolveFailure", "TmpResolveFailure" };
+                 errTransient = std::find(std::begin(reasons), std::end(reasons), failReason) != std::end(reasons);
+              }
+              if (errTransient == false)
+              {
+                 auto const reasons = { "HashSumMismatch", "WeakHashSums", "MaximumSizeExceeded" };
+                 errAuthErr = std::find(std::begin(reasons), std::end(reasons), failReason) != std::end(reasons);
+              }
+           }

 
 

-           Owner->Failed(Message,Config);
+           for (auto const Owner: ItmOwners)
+           {
+              if (errAuthErr && Owner->GetExpectedHashes().empty() == false)
+                 Owner->Status = pkgAcquire::Item::StatAuthError;
+              else if (errTransient)
+                 Owner->Status = pkgAcquire::Item::StatTransientNetworkError;
+
+              if (isDoomedItem(Owner) == false)
+                 Owner->Failed(Message,Config);
+              if (Log != nullptr)
+                 Log->Fail(Owner->GetItemDesc());
+           }

            ItemDone();
 
            ItemDone();
 

-           if (Log != 0)
-              Log->Fail(Desc);
-

            break;
            break;

-        }       
-        
-        // 401 General Failure
-        case 401:
+        }
+
+        case MessageType::GENERAL_FAILURE:

         _error->Error("Method %s General failure: %s",Access.c_str(),LookupTag(Message,"Message").c_str());
         break;
         _error->Error("Method %s General failure: %s",Access.c_str(),LookupTag(Message,"Message").c_str());
         break;

-        
-        // 403 Media Change
-        case 403:
-        MediaChange(Message); 
+
+        case MessageType::MEDIA_CHANGE:
+        MediaChange(Message);

         break;
         break;

-      }      
+      }

    }
    return true;
 }
    }
    return true;
 }


@@ -422,7 +555,7 @@ bool pkgAcquire::Worker::Capabilities(string Message)
 {
    if (Config == 0)
       return true;
 {
    if (Config == 0)
       return true;

-   
+

    Config->Version = LookupTag(Message,"Version");
    Config->SingleInstance = StringToBool(LookupTag(Message,"Single-Instance"),false);
    Config->Pipeline = StringToBool(LookupTag(Message,"Pipeline"),false);
    Config->Version = LookupTag(Message,"Version");
    Config->SingleInstance = StringToBool(LookupTag(Message,"Single-Instance"),false);
    Config->Pipeline = StringToBool(LookupTag(Message,"Pipeline"),false);


@@ -437,13 +570,13 @@ bool pkgAcquire::Worker::Capabilities(string Message)
       clog << "Configured access method " << Config->Access << endl;
       clog << "Version:" << Config->Version <<
              " SingleInstance:" << Config->SingleInstance <<
       clog << "Configured access method " << Config->Access << endl;
       clog << "Version:" << Config->Version <<
              " SingleInstance:" << Config->SingleInstance <<

-             " Pipeline:" << Config->Pipeline << 
-             " SendConfig:" << Config->SendConfig << 
-             " LocalOnly: " << Config->LocalOnly << 
-             " NeedsCleanup: " << Config->NeedsCleanup << 
+             " Pipeline:" << Config->Pipeline <<
+             " SendConfig:" << Config->SendConfig <<
+             " LocalOnly: " << Config->LocalOnly <<
+             " NeedsCleanup: " << Config->NeedsCleanup <<

              " Removable: " << Config->Removable << endl;
    }
              " Removable: " << Config->Removable << endl;
    }

-   
+

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


@@ -453,14 +586,14 @@ bool pkgAcquire::Worker::Capabilities(string Message)
 bool pkgAcquire::Worker::MediaChange(string Message)
 {
    int status_fd = _config->FindI("APT::Status-Fd",-1);
 bool pkgAcquire::Worker::MediaChange(string Message)
 {
    int status_fd = _config->FindI("APT::Status-Fd",-1);

-   if(status_fd > 0) 
+   if(status_fd > 0)

    {
       string Media = LookupTag(Message,"Media");
    {
       string Media = LookupTag(Message,"Media");

-      string Drive = LookupTag(Message,"Drive"); 
+      string Drive = LookupTag(Message,"Drive");

       ostringstream msg,status;
       ioprintf(msg,_("Please insert the disc labeled: "
                     "'%s' "
       ostringstream msg,status;
       ioprintf(msg,_("Please insert the disc labeled: "
                     "'%s' "

-                    "in the drive '%s' and press enter."),
+                    "in the drive '%s' and press [Enter]."),

               Media.c_str(),Drive.c_str());
       status << "media-change: "  // message
             << Media  << ":"     // media
               Media.c_str(),Drive.c_str());
       status << "media-change: "  // message
             << Media  << ":"     // media


@@ -526,28 +659,67 @@ bool pkgAcquire::Worker::QueueItem(pkgAcquire::Queue::QItem *Item)
 {
    if (OutFd == -1)
       return false;
 {
    if (OutFd == -1)
       return false;

-   
+
+   HashStringList const hsl = Item->GetExpectedHashes();
+
+   if (isDoomedItem(Item->Owner))
+      return true;
+
+   if (hsl.usable() == false && Item->Owner->HashesRequired() &&
+        _config->Exists("Acquire::ForceHash") == false)
+   {
+      std::string const Message = "400 URI Failure"
+        "\nURI: " + Item->URI +
+        "\nFilename: " + Item->Owner->DestFile +
+        "\nFailReason: WeakHashSums";
+
+      auto const ItmOwners = Item->Owners;
+      for (auto &O: ItmOwners)
+      {
+        O->Status = pkgAcquire::Item::StatAuthError;
+        O->Failed(Message, Config);
+        if (Log != nullptr)
+           Log->Fail(O->GetItemDesc());
+      }
+      // "queued" successfully, the item just instantly failed
+      return true;
+   }
+

    string Message = "600 URI Acquire\n";
    Message.reserve(300);
    Message += "URI: " + Item->URI;
    Message += "\nFilename: " + Item->Owner->DestFile;
    string Message = "600 URI Acquire\n";
    Message.reserve(300);
    Message += "URI: " + Item->URI;
    Message += "\nFilename: " + Item->Owner->DestFile;

-   HashStringList const hsl = Item->Owner->HashSums();
+

    for (HashStringList::const_iterator hs = hsl.begin(); hs != hsl.end(); ++hs)
       Message += "\nExpected-" + hs->HashType() + ": " + hs->HashValue();
    for (HashStringList::const_iterator hs = hsl.begin(); hs != hsl.end(); ++hs)
       Message += "\nExpected-" + hs->HashType() + ": " + hs->HashValue();

-   if(Item->Owner->FileSize > 0)
+
+   if (hsl.FileSize() == 0)

    {
    {

-      string MaximumSize;
-      strprintf(MaximumSize, "%llu", Item->Owner->FileSize);
-      Message += "\nMaximum-Size: " + MaximumSize;
+      unsigned long long FileSize = Item->GetMaximumSize();
+      if(FileSize > 0)
+      {
+        string MaximumSize;
+        strprintf(MaximumSize, "%llu", FileSize);
+        Message += "\nMaximum-Size: " + MaximumSize;
+      }

    }
    }

-   Message += Item->Owner->Custom600Headers();
+
+   Item->SyncDestinationFiles();
+   Message += Item->Custom600Headers();

    Message += "\n\n";
    Message += "\n\n";

-   
+
+   if (RealFileExists(Item->Owner->DestFile))
+   {
+      std::string const SandboxUser = _config->Find("APT::Sandbox::User");
+      ChangeOwnerAndPermissionOfFile("Item::QueueURI", Item->Owner->DestFile.c_str(),
+                                     SandboxUser.c_str(), "root", 0600);
+   }
+

    if (Debug == true)
       clog << " -> " << Access << ':' << QuoteString(Message,"\n") << endl;
    OutQueue += Message;
    OutReady = true;
    if (Debug == true)
       clog << " -> " << Access << ':' << QuoteString(Message,"\n") << endl;
    OutQueue += Message;
    OutReady = true;

-   
+

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


@@ -569,7 +741,7 @@ bool pkgAcquire::Worker::OutFdReady()
    OutQueue.erase(0,Res);
    if (OutQueue.empty() == true)
       OutReady = false;
    OutQueue.erase(0,Res);
    if (OutQueue.empty() == true)
       OutReady = false;

-   
+

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


@@ -591,7 +763,7 @@ bool pkgAcquire::Worker::InFdReady()
 bool pkgAcquire::Worker::MethodFailure()
 {
    _error->Error("Method %s has died unexpectedly!",Access.c_str());
 bool pkgAcquire::Worker::MethodFailure()
 {
    _error->Error("Method %s has died unexpectedly!",Access.c_str());

-   
+

    // do not reap the child here to show meaningfull error to the user
    ExecWait(Process,Access.c_str(),false);
    Process = -1;
    // do not reap the child here to show meaningfull error to the user
    ExecWait(Process,Access.c_str(),false);
    Process = -1;


@@ -603,26 +775,22 @@ bool pkgAcquire::Worker::MethodFailure()
    InReady = false;
    OutQueue = string();
    MessageQueue.erase(MessageQueue.begin(),MessageQueue.end());
    InReady = false;
    OutQueue = string();
    MessageQueue.erase(MessageQueue.begin(),MessageQueue.end());

-   
+

    return false;
 }
                                                                        /*}}}*/
    return false;
 }
                                                                        /*}}}*/

-// Worker::Pulse - Called periodically                                         /*{{{*/
+// Worker::Pulse - Called periodically                                 /*{{{*/

 // ---------------------------------------------------------------------
 /* */
 void pkgAcquire::Worker::Pulse()
 {
    if (CurrentItem == 0)
       return;
 // ---------------------------------------------------------------------
 /* */
 void pkgAcquire::Worker::Pulse()
 {
    if (CurrentItem == 0)
       return;

- 
+

    struct stat Buf;
    if (stat(CurrentItem->Owner->DestFile.c_str(),&Buf) != 0)
       return;
    CurrentSize = Buf.st_size;
    struct stat Buf;
    if (stat(CurrentItem->Owner->DestFile.c_str(),&Buf) != 0)
       return;
    CurrentSize = Buf.st_size;

-   
-   // Hmm? Should not happen...
-   if (CurrentSize > TotalSize && TotalSize != 0)
-      TotalSize = CurrentSize;

 }
                                                                        /*}}}*/
 // Worker::ItemDone - Called when the current item is finished         /*{{{*/
 }
                                                                        /*}}}*/
 // Worker::ItemDone - Called when the current item is finished         /*{{{*/


@@ -636,3 +804,33 @@ void pkgAcquire::Worker::ItemDone()
    Status = string();
 }
                                                                        /*}}}*/
    Status = string();
 }
                                                                        /*}}}*/

+void pkgAcquire::Worker::PrepareFiles(char const * const caller, pkgAcquire::Queue::QItem const * const Itm)/*{{{*/
+{
+   if (RealFileExists(Itm->Owner->DestFile))
+   {
+      ChangeOwnerAndPermissionOfFile(caller, Itm->Owner->DestFile.c_str(), "root", "root", 0644);
+      std::string const filename = Itm->Owner->DestFile;
+      for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+      {
+        pkgAcquire::Item const * const Owner = *O;
+        if (Owner->DestFile == filename || filename == "/dev/null")
+           continue;
+        RemoveFile("PrepareFiles", Owner->DestFile);
+        if (link(filename.c_str(), Owner->DestFile.c_str()) != 0)
+        {
+           // different mounts can't happen for us as we download to lists/ by default,
+           // but if the system is reused by others the locations can potentially be on
+           // different disks, so use symlink as poor-men replacement.
+           // FIXME: Real copying as last fallback, but that is costly, so offload to a method preferable
+           if (symlink(filename.c_str(), Owner->DestFile.c_str()) != 0)
+              _error->Error("Can't create (sym)link of file %s to %s", filename.c_str(), Owner->DestFile.c_str());
+        }
+      }
+   }
+   else
+   {
+      for (pkgAcquire::Queue::QItem::owner_iterator O = Itm->Owners.begin(); O != Itm->Owners.end(); ++O)
+        RemoveFile("PrepareFiles", (*O)->DestFile);
+   }
+}
+                                                                       /*}}}*/