use HashStringList in the acquire system

It is not very extensible to have the supported Hashes hardcoded
everywhere and especially if it is part of virtual method names.
It is also possible that a method does not support the 'best' hash
(yet), so we might end up not being able to verify a file even though we
have a common subset of supported hashes. And those are just two of the
cases in which it is handy to have a more dynamic selection.

The downside is that this is a MAJOR API break, but the HashStringList
has a string constructor for compatibility, so with a bit of luck the
few frontends playing with the acquire system directly are okay.

1 files changed, 95 insertions, 107 deletions

diff --git a/apt-pkg/acquire-item.cc b/apt-pkg/acquire-item.cc
index 913764f64..1156d6f33 100644
--- a/apt-pkg/acquire-item.cc
+++ b/apt-pkg/acquire-item.cc
@@ -50,6 +50,19 @@
 
 using namespace std;
 
+static void printHashSumComparision(std::string const &URI, HashStringList const &Expected, HashStringList const &Actual) /*{{{*/
+{
+   if (_config->FindB("Debug::Acquire::HashSumMismatch", false) == false)
+      return;
+   std::cerr << std::endl << URI << ":" << std::endl << " Expected Hash: " << std::endl;
+   for (HashStringList::const_iterator hs = Expected.begin(); hs != Expected.end(); ++hs)
+      std::cerr <<  "\t- " << hs->toStr() << std::endl;
+   std::cerr << " Actual Hash: " << std::endl;
+   for (HashStringList::const_iterator hs = Actual.begin(); hs != Actual.end(); ++hs)
+      std::cerr <<  "\t- " << hs->toStr() << std::endl;
+}
+									/*}}}*/
+
 // Acquire::Item::Item - Constructor					/*{{{*/
 // ---------------------------------------------------------------------
 /* */
@@ -118,7 +131,7 @@ void pkgAcquire::Item::Start(string /*Message*/,unsigned long long Size)
 // Acquire::Item::Done - Item downloaded OK				/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void pkgAcquire::Item::Done(string Message,unsigned long long Size,string /*Hash*/,
+void pkgAcquire::Item::Done(string Message,unsigned long long Size,HashStringList const &/*Hash*/,
 			    pkgAcquire::MethodConfig * /*Cnf*/)
 {
    // We just downloaded something..
@@ -229,8 +242,8 @@ void pkgAcquire::Item::ReportMirrorFailure(string FailCode)
    possibly query additional files */
 pkgAcqSubIndex::pkgAcqSubIndex(pkgAcquire *Owner, string const &URI,
 				 string const &URIDesc, string const &ShortDesc,
-				 HashString const &ExpectedHash)
-   : Item(Owner), ExpectedHash(ExpectedHash)
+				 HashStringList const &ExpectedHashes)
+   : Item(Owner), ExpectedHashes(ExpectedHashes)
 {
    /* XXX: Beware: Currently this class does nothing (of value) anymore ! */
    Debug = _config->FindB("Debug::pkgAcquire::SubIndex",false);
@@ -252,7 +265,7 @@ pkgAcqSubIndex::pkgAcqSubIndex(pkgAcquire *Owner, string const &URI,
 // AcqSubIndex::Custom600Headers - Insert custom request headers	/*{{{*/
 // ---------------------------------------------------------------------
 /* The only header we use is the last-modified header. */
-string pkgAcqSubIndex::Custom600Headers()
+string pkgAcqSubIndex::Custom600Headers() const
 {
    string Final = _config->FindDir("Dir::State::lists");
    Final += URItoFileName(Desc.URI);
@@ -275,7 +288,7 @@ void pkgAcqSubIndex::Failed(string Message,pkgAcquire::MethodConfig * /*Cnf*/)/*
    // No good Index is provided
 }
 									/*}}}*/
-void pkgAcqSubIndex::Done(string Message,unsigned long long Size,string Md5Hash,	/*{{{*/
+void pkgAcqSubIndex::Done(string Message,unsigned long long Size,HashStringList const &Hashes,	/*{{{*/
 			   pkgAcquire::MethodConfig *Cnf)
 {
    if(Debug)
@@ -297,7 +310,7 @@ void pkgAcqSubIndex::Done(string Message,unsigned long long Size,string Md5Hash,
       return;
    }
 
-   Item::Done(Message,Size,Md5Hash,Cnf);
+   Item::Done(Message, Size, Hashes, Cnf);
 
    string FinalFile = _config->FindDir("Dir::State::lists")+URItoFileName(Desc.URI);
 
@@ -343,12 +356,11 @@ bool pkgAcqSubIndex::ParseIndex(string const &IndexFile)		/*{{{*/
  * the original packages file
  */
 pkgAcqDiffIndex::pkgAcqDiffIndex(pkgAcquire *Owner,
-                                 IndexTarget const *Target,
-				 HashString ExpectedHash,
-                                 indexRecords *MetaIndexParser)
-   : Item(Owner), ExpectedHash(ExpectedHash), Target(Target),
+      struct IndexTarget const * const Target,
+      HashStringList const &ExpectedHashes,
+      indexRecords *MetaIndexParser)
+   : Item(Owner), ExpectedHashes(ExpectedHashes), Target(Target),
      MetaIndexParser(MetaIndexParser)
-     
 {
    
    Debug = _config->FindB("Debug::pkgAcquire::Diffs",false);
@@ -393,7 +405,7 @@ pkgAcqDiffIndex::pkgAcqDiffIndex(pkgAcquire *Owner,
 // AcqIndex::Custom600Headers - Insert custom request headers		/*{{{*/
 // ---------------------------------------------------------------------
 /* The only header we use is the last-modified header. */
-string pkgAcqDiffIndex::Custom600Headers()
+string pkgAcqDiffIndex::Custom600Headers() const
 {
    string Final = _config->FindDir("Dir::State::lists");
    Final += URItoFileName(RealURI) + string(".IndexDiff");
@@ -447,7 +459,7 @@ bool pkgAcqDiffIndex::ParseDiffIndex(string IndexDiffFile)		/*{{{*/
 	 // list cleanup needs to know that this file as well as the already
 	 // present index is ours, so we create an empty diff to save it for us
 	 new pkgAcqIndexDiffs(Owner, RealURI, Description, Desc.ShortDesc,
-	       ExpectedHash, ServerSha1, available_patches);
+	       ExpectedHashes, ServerSha1, available_patches);
 	 return true;
       }
       else
@@ -533,12 +545,12 @@ bool pkgAcqDiffIndex::ParseDiffIndex(string IndexDiffFile)		/*{{{*/
 
 	 if (pdiff_merge == false)
 	    new pkgAcqIndexDiffs(Owner, RealURI, Description, Desc.ShortDesc,
-		  ExpectedHash, ServerSha1, available_patches);
+		  ExpectedHashes, ServerSha1, available_patches);
 	 else
 	 {
 	    std::vector<pkgAcqIndexMergeDiffs*> *diffs = new std::vector<pkgAcqIndexMergeDiffs*>(available_patches.size());
 	    for(size_t i = 0; i < available_patches.size(); ++i)
-	       (*diffs)[i] = new pkgAcqIndexMergeDiffs(Owner, RealURI, Description, Desc.ShortDesc, ExpectedHash,
+	       (*diffs)[i] = new pkgAcqIndexMergeDiffs(Owner, RealURI, Description, Desc.ShortDesc, ExpectedHashes,
 		     available_patches[i], diffs);
 	 }
 
@@ -563,20 +575,20 @@ void pkgAcqDiffIndex::Failed(string Message,pkgAcquire::MethodConfig * /*Cnf*/)/
       std::clog << "pkgAcqDiffIndex failed: " << Desc.URI << " with " << Message << std::endl
 		<< "Falling back to normal index file acquire" << std::endl;
 
-   new pkgAcqIndex(Owner, Target, ExpectedHash, MetaIndexParser);
+   new pkgAcqIndex(Owner, Target, ExpectedHashes, MetaIndexParser);
 
    Complete = false;
    Status = StatDone;
    Dequeue();
 }
 									/*}}}*/
-void pkgAcqDiffIndex::Done(string Message,unsigned long long Size,string Md5Hash,	/*{{{*/
+void pkgAcqDiffIndex::Done(string Message,unsigned long long Size,HashStringList const &Hashes,	/*{{{*/
 			   pkgAcquire::MethodConfig *Cnf)
 {
    if(Debug)
       std::clog << "pkgAcqDiffIndex::Done(): " << Desc.URI << std::endl;
 
-   Item::Done(Message,Size,Md5Hash,Cnf);
+   Item::Done(Message, Size, Hashes, Cnf);
 
    string FinalFile;
    FinalFile = _config->FindDir("Dir::State::lists")+URItoFileName(RealURI);
@@ -607,10 +619,10 @@ void pkgAcqDiffIndex::Done(string Message,unsigned long long Size,string Md5Hash
  */
 pkgAcqIndexDiffs::pkgAcqIndexDiffs(pkgAcquire *Owner,
 				   string URI,string URIDesc,string ShortDesc,
-				   HashString ExpectedHash, 
+				   HashStringList const &ExpectedHashes,
 				   string ServerSha1,
 				   vector<DiffInfo> diffs)
-   : Item(Owner), RealURI(URI), ExpectedHash(ExpectedHash), 
+   : Item(Owner), RealURI(URI), ExpectedHashes(ExpectedHashes),
      available_patches(diffs), ServerSha1(ServerSha1)
 {
    
@@ -642,7 +654,7 @@ void pkgAcqIndexDiffs::Failed(string Message,pkgAcquire::MethodConfig * /*Cnf*/)
       std::clog << "pkgAcqIndexDiffs failed: " << Desc.URI << " with " << Message << std::endl
 		<< "Falling back to normal index file acquire" << std::endl;
    new pkgAcqIndex(Owner, RealURI, Description,Desc.ShortDesc, 
-		   ExpectedHash);
+		   ExpectedHashes);
    Finish();
 }
 									/*}}}*/
@@ -656,7 +668,7 @@ void pkgAcqIndexDiffs::Finish(bool allDone)
       DestFile = _config->FindDir("Dir::State::lists");
       DestFile += URItoFileName(RealURI);
 
-      if(!ExpectedHash.empty() && !ExpectedHash.VerifyFile(DestFile))
+      if(ExpectedHashes.usable() && !ExpectedHashes.VerifyFile(DestFile))
       {
 	 RenameOnError(HashSumMismatch);
 	 Dequeue();
@@ -734,13 +746,13 @@ bool pkgAcqIndexDiffs::QueueNextDiff()					/*{{{*/
    return true;
 }
 									/*}}}*/
-void pkgAcqIndexDiffs::Done(string Message,unsigned long long Size,string Md5Hash,	/*{{{*/
+void pkgAcqIndexDiffs::Done(string Message,unsigned long long Size, HashStringList const &Hashes,	/*{{{*/
 			    pkgAcquire::MethodConfig *Cnf)
 {
    if(Debug)
       std::clog << "pkgAcqIndexDiffs::Done(): " << Desc.URI << std::endl;
 
-   Item::Done(Message,Size,Md5Hash,Cnf);
+   Item::Done(Message, Size, Hashes, Cnf);
 
    string FinalFile;
    FinalFile = _config->FindDir("Dir::State::lists")+URItoFileName(RealURI);
@@ -783,7 +795,7 @@ void pkgAcqIndexDiffs::Done(string Message,unsigned long long Size,string Md5Has
       // see if there is more to download
       if(available_patches.empty() == false) {
 	 new pkgAcqIndexDiffs(Owner, RealURI, Description, Desc.ShortDesc,
-			      ExpectedHash, ServerSha1, available_patches);
+			      ExpectedHashes, ServerSha1, available_patches);
 	 return Finish();
       } else 
 	 return Finish(true);
@@ -793,10 +805,10 @@ void pkgAcqIndexDiffs::Done(string Message,unsigned long long Size,string Md5Has
 // AcqIndexMergeDiffs::AcqIndexMergeDiffs - Constructor			/*{{{*/
 pkgAcqIndexMergeDiffs::pkgAcqIndexMergeDiffs(pkgAcquire *Owner,
 				   string const &URI, string const &URIDesc,
-				   string const &ShortDesc, HashString const &ExpectedHash,
+				   string const &ShortDesc, HashStringList const &ExpectedHashes,
 				   DiffInfo const &patch,
 				   std::vector<pkgAcqIndexMergeDiffs*> const * const allPatches)
-   : Item(Owner), RealURI(URI), ExpectedHash(ExpectedHash),
+   : Item(Owner), RealURI(URI), ExpectedHashes(ExpectedHashes),
      patch(patch),allPatches(allPatches), State(StateFetchDiff)
 {
 
@@ -839,16 +851,16 @@ void pkgAcqIndexMergeDiffs::Failed(string Message,pkgAcquire::MethodConfig * /*C
    State = StateErrorDiff;
    std::clog << "Falling back to normal index file acquire" << std::endl;
    new pkgAcqIndex(Owner, RealURI, Description,Desc.ShortDesc,
-		   ExpectedHash);
+		   ExpectedHashes);
 }
 									/*}}}*/
-void pkgAcqIndexMergeDiffs::Done(string Message,unsigned long long Size,string Md5Hash,	/*{{{*/
+void pkgAcqIndexMergeDiffs::Done(string Message,unsigned long long Size,HashStringList const &Hashes,	/*{{{*/
 			    pkgAcquire::MethodConfig *Cnf)
 {
    if(Debug)
       std::clog << "pkgAcqIndexMergeDiffs::Done(): " << Desc.URI << std::endl;
 
-   Item::Done(Message,Size,Md5Hash,Cnf);
+   Item::Done(Message,Size,Hashes,Cnf);
 
    string const FinalFile = _config->FindDir("Dir::State::lists") + URItoFileName(RealURI);
 
@@ -884,7 +896,7 @@ void pkgAcqIndexMergeDiffs::Done(string Message,unsigned long long Size,string M
    else if (State == StateApplyDiff)
    {
       // see if we really got the expected file
-      if(!ExpectedHash.empty() && !ExpectedHash.VerifyFile(DestFile))
+      if(ExpectedHashes.usable() && !ExpectedHashes.VerifyFile(DestFile))
       {
 	 RenameOnError(HashSumMismatch);
 	 return;
@@ -921,8 +933,8 @@ void pkgAcqIndexMergeDiffs::Done(string Message,unsigned long long Size,string M
    instantiated to fetch the revision file */   
 pkgAcqIndex::pkgAcqIndex(pkgAcquire *Owner,
 			 string URI,string URIDesc,string ShortDesc,
-			 HashString ExpectedHash, string comprExt)
-   : Item(Owner), RealURI(URI), ExpectedHash(ExpectedHash), Target(0),
+			 HashStringList const &ExpectedHashes, string comprExt)
+   : Item(Owner), RealURI(URI), ExpectedHashes(ExpectedHashes), Target(0),
      MetaIndexParser(0)
 {
    if(comprExt.empty() == true)
@@ -940,14 +952,14 @@ pkgAcqIndex::pkgAcqIndex(pkgAcquire *Owner,
 
    Init(URI, URIDesc, ShortDesc);
 }
-pkgAcqIndex::pkgAcqIndex(pkgAcquire *Owner, IndexTarget const *Target,
-			 HashString const &ExpectedHash, indexRecords *MetaIndexParser)
-   : Item(Owner), RealURI(Target->URI), ExpectedHash(ExpectedHash)
+pkgAcqIndex::pkgAcqIndex(pkgAcquire *Owner, struct IndexTarget const * const Target,
+			 HashStringList const &ExpectedHashes, indexRecords *MetaIndexParser)
+   : Item(Owner), RealURI(Target->URI), ExpectedHashes(ExpectedHashes)
 {
    // autoselect the compression method
    std::vector<std::string> types = APT::Configuration::getCompressionTypes();
    CompressionExtension = "";
-   if (ExpectedHash.empty() == false)
+   if (ExpectedHashes.usable())
    {
       for (std::vector<std::string>::const_iterator t = types.begin(); t != types.end(); ++t)
 	 if (*t == "uncompressed" || MetaIndexParser->Exists(string(Target->MetaKey).append(".").append(*t)) == true)
@@ -1016,7 +1028,7 @@ void pkgAcqIndex::Init(string const &URI, string const &URIDesc, string const &S
 // AcqIndex::Custom600Headers - Insert custom request headers		/*{{{*/
 // ---------------------------------------------------------------------
 /* The only header we use is the last-modified header. */
-string pkgAcqIndex::Custom600Headers()
+string pkgAcqIndex::Custom600Headers() const
 {
    string Final = _config->FindDir("Dir::State::lists");
    Final += URItoFileName(RealURI);
@@ -1062,22 +1074,17 @@ void pkgAcqIndex::Failed(string Message,pkgAcquire::MethodConfig *Cnf)	/*{{{*/
    to the uncompressed version of the file. If this is so the file
    is copied into the partial directory. In all other cases the file
    is decompressed with a gzip uri. */
-void pkgAcqIndex::Done(string Message,unsigned long long Size,string Hash,
+void pkgAcqIndex::Done(string Message,unsigned long long Size,HashStringList const &Hashes,
 		       pkgAcquire::MethodConfig *Cfg)
 {
-   Item::Done(Message,Size,Hash,Cfg);
+   Item::Done(Message,Size,Hashes,Cfg);
 
    if (Decompression == true)
    {
-      if (_config->FindB("Debug::pkgAcquire::Auth", false))
-      {
-         std::cerr << std::endl << RealURI << ": Computed Hash: " << Hash;
-         std::cerr << "  Expected Hash: " << ExpectedHash.toStr() << std::endl;
-      }
-
-      if (!ExpectedHash.empty() && ExpectedHash.toStr() != Hash)
+      if (ExpectedHashes.usable() && ExpectedHashes != Hashes)
       {
 	 RenameOnError(HashSumMismatch);
+	 printHashSumComparision(RealURI, ExpectedHashes, Hashes);
          return;
       }
 
@@ -1199,12 +1206,12 @@ void pkgAcqIndex::Done(string Message,unsigned long long Size,string Hash,
 /* The Translation file is added to the queue */
 pkgAcqIndexTrans::pkgAcqIndexTrans(pkgAcquire *Owner,
 			    string URI,string URIDesc,string ShortDesc) 
-  : pkgAcqIndex(Owner, URI, URIDesc, ShortDesc, HashString(), "")
+  : pkgAcqIndex(Owner, URI, URIDesc, ShortDesc, HashStringList(), "")
 {
 }
-pkgAcqIndexTrans::pkgAcqIndexTrans(pkgAcquire *Owner, IndexTarget const *Target,
-			 HashString const &ExpectedHash, indexRecords *MetaIndexParser)
-  : pkgAcqIndex(Owner, Target, ExpectedHash, MetaIndexParser)
+pkgAcqIndexTrans::pkgAcqIndexTrans(pkgAcquire *Owner, struct IndexTarget const * const Target,
+			 HashStringList const &ExpectedHashes, indexRecords *MetaIndexParser)
+  : pkgAcqIndex(Owner, Target, ExpectedHashes, MetaIndexParser)
 {
    // load the filesize
    indexRecords::checkSum *Record = MetaIndexParser->Lookup(string(Target->MetaKey));
@@ -1214,7 +1221,7 @@ pkgAcqIndexTrans::pkgAcqIndexTrans(pkgAcquire *Owner, IndexTarget const *Target,
 									/*}}}*/
 // AcqIndexTrans::Custom600Headers - Insert custom request headers	/*{{{*/
 // ---------------------------------------------------------------------
-string pkgAcqIndexTrans::Custom600Headers()
+string pkgAcqIndexTrans::Custom600Headers() const
 {
    string Final = _config->FindDir("Dir::State::lists");
    Final += URItoFileName(RealURI);
@@ -1311,7 +1318,7 @@ pkgAcqMetaSig::~pkgAcqMetaSig()						/*{{{*/
 // pkgAcqMetaSig::Custom600Headers - Insert custom request headers	/*{{{*/
 // ---------------------------------------------------------------------
 /* The only header we use is the last-modified header. */
-string pkgAcqMetaSig::Custom600Headers()
+string pkgAcqMetaSig::Custom600Headers() const
 {
    struct stat Buf;
    if (stat(LastGoodSig.c_str(),&Buf) != 0)
@@ -1320,10 +1327,10 @@ string pkgAcqMetaSig::Custom600Headers()
    return "\nIndex-File: true\nLast-Modified: " + TimeRFC1123(Buf.st_mtime);
 }
 
-void pkgAcqMetaSig::Done(string Message,unsigned long long Size,string MD5,
+void pkgAcqMetaSig::Done(string Message,unsigned long long Size, HashStringList const &Hashes,
 			 pkgAcquire::MethodConfig *Cfg)
 {
-   Item::Done(Message,Size,MD5,Cfg);
+   Item::Done(Message, Size, Hashes, Cfg);
 
    string FileName = LookupTag(Message,"Filename");
    if (FileName.empty() == true)
@@ -1426,7 +1433,7 @@ pkgAcqMetaIndex::pkgAcqMetaIndex(pkgAcquire *Owner,			/*{{{*/
 // pkgAcqMetaIndex::Custom600Headers - Insert custom request headers	/*{{{*/
 // ---------------------------------------------------------------------
 /* The only header we use is the last-modified header. */
-string pkgAcqMetaIndex::Custom600Headers()
+string pkgAcqMetaIndex::Custom600Headers() const
 {
    string Final = _config->FindDir("Dir::State::lists");
    Final += URItoFileName(RealURI);
@@ -1438,10 +1445,10 @@ string pkgAcqMetaIndex::Custom600Headers()
    return "\nIndex-File: true\nLast-Modified: " + TimeRFC1123(Buf.st_mtime);
 }
 									/*}}}*/
-void pkgAcqMetaIndex::Done(string Message,unsigned long long Size,string Hash,	/*{{{*/
+void pkgAcqMetaIndex::Done(string Message,unsigned long long Size,HashStringList const &Hashes,	/*{{{*/
 			   pkgAcquire::MethodConfig *Cfg)
 {
-   Item::Done(Message,Size,Hash,Cfg);
+   Item::Done(Message,Size,Hashes,Cfg);
 
    // MetaIndexes are done in two passes: one to download the
    // metaindex with an appropriate method, and a second to verify it
@@ -1616,8 +1623,8 @@ void pkgAcqMetaIndex::QueueIndexes(bool verify)				/*{{{*/
         Target != IndexTargets->end();
         ++Target)
    {
-      HashString ExpectedIndexHash;
-      indexRecords::checkSum *Record = MetaIndexParser->Lookup((*Target)->MetaKey);
+      HashStringList ExpectedIndexHashes;
+      const indexRecords::checkSum *Record = MetaIndexParser->Lookup((*Target)->MetaKey);
       bool compressedAvailable = false;
       if (Record == NULL)
       {
@@ -1640,14 +1647,16 @@ void pkgAcqMetaIndex::QueueIndexes(bool verify)				/*{{{*/
       }
       else
       {
-	 ExpectedIndexHash = Record->Hash;
+	 ExpectedIndexHashes = Record->Hashes;
 	 if (_config->FindB("Debug::pkgAcquire::Auth", false))
 	 {
-	    std::cerr << "Queueing: " << (*Target)->URI << std::endl;
-	    std::cerr << "Expected Hash: " << ExpectedIndexHash.toStr() << std::endl;
+	    std::cerr << "Queueing: " << (*Target)->URI << std::endl
+	       << "Expected Hash:" << std::endl;
+	    for (HashStringList::const_iterator hs = ExpectedIndexHashes.begin(); hs != ExpectedIndexHashes.end(); ++hs)
+	       std::cerr <<  "\t- " << hs->toStr() << std::endl;
 	    std::cerr << "For: " << Record->MetaKeyFilename << std::endl;
 	 }
-	 if (verify == true && ExpectedIndexHash.empty() == true && (*Target)->IsOptional() == false)
+	 if (verify == true && ExpectedIndexHashes.empty() == true && (*Target)->IsOptional() == false)
 	 {
 	    Status = StatAuthError;
 	    strprintf(ErrorText, _("Unable to find hash sum for '%s' in Release file"), (*Target)->MetaKey.c_str());
@@ -1659,14 +1668,14 @@ void pkgAcqMetaIndex::QueueIndexes(bool verify)				/*{{{*/
       {
 	 if ((*Target)->IsSubIndex() == true)
 	    new pkgAcqSubIndex(Owner, (*Target)->URI, (*Target)->Description,
-				(*Target)->ShortDesc, ExpectedIndexHash);
+				(*Target)->ShortDesc, ExpectedIndexHashes);
 	 else if (transInRelease == false || Record != NULL || compressedAvailable == true)
 	 {
 	    if (_config->FindB("Acquire::PDiffs",true) == true && transInRelease == true &&
 		MetaIndexParser->Exists((*Target)->MetaKey + ".diff/Index") == true)
-	       new pkgAcqDiffIndex(Owner, *Target, ExpectedIndexHash, MetaIndexParser);
+	       new pkgAcqDiffIndex(Owner, *Target, ExpectedIndexHashes, MetaIndexParser);
 	    else
-	       new pkgAcqIndexTrans(Owner, *Target, ExpectedIndexHash, MetaIndexParser);
+	       new pkgAcqIndexTrans(Owner, *Target, ExpectedIndexHashes, MetaIndexParser);
 	 }
 	 continue;
       }
@@ -1677,9 +1686,9 @@ void pkgAcqMetaIndex::QueueIndexes(bool verify)				/*{{{*/
          instead, but passing the required info to it is to much hassle */
       if(_config->FindB("Acquire::PDiffs",true) == true && (verify == false ||
 	  MetaIndexParser->Exists((*Target)->MetaKey + ".diff/Index") == true))
-	 new pkgAcqDiffIndex(Owner, *Target, ExpectedIndexHash, MetaIndexParser);
+	 new pkgAcqDiffIndex(Owner, *Target, ExpectedIndexHashes, MetaIndexParser);
       else
-	 new pkgAcqIndex(Owner, *Target, ExpectedIndexHash, MetaIndexParser);
+	 new pkgAcqIndex(Owner, *Target, ExpectedIndexHashes, MetaIndexParser);
    }
 }
 									/*}}}*/
@@ -1868,7 +1877,7 @@ pkgAcqMetaClearSig::~pkgAcqMetaClearSig()				/*{{{*/
 // pkgAcqMetaClearSig::Custom600Headers - Insert custom request headers	/*{{{*/
 // ---------------------------------------------------------------------
 // FIXME: this can go away once the InRelease file is used widely
-string pkgAcqMetaClearSig::Custom600Headers()
+string pkgAcqMetaClearSig::Custom600Headers() const
 {
    string Final = _config->FindDir("Dir::State::lists");
    Final += URItoFileName(RealURI);
@@ -2002,7 +2011,6 @@ pkgAcqArchive::pkgAcqArchive(pkgAcquire *Owner,pkgSourceList *Sources,
    checking later. */
 bool pkgAcqArchive::QueueNext()
 {
-   string const ForceHash = _config->Find("Acquire::ForceHash");
    for (; Vf.end() == false; ++Vf)
    {
       // Ignore not source sources
@@ -2023,31 +2031,10 @@ bool pkgAcqArchive::QueueNext()
       pkgRecords::Parser &Parse = Recs->Lookup(Vf);
       if (_error->PendingError() == true)
 	 return false;
-      
+
       string PkgFile = Parse.FileName();
-      if (ForceHash.empty() == false)
-      {
-	 if(stringcasecmp(ForceHash, "sha512") == 0)
-	    ExpectedHash = HashString("SHA512", Parse.SHA512Hash());
-	 else if(stringcasecmp(ForceHash, "sha256") == 0)
-	    ExpectedHash = HashString("SHA256", Parse.SHA256Hash());
-	 else if (stringcasecmp(ForceHash, "sha1") == 0)
-	    ExpectedHash = HashString("SHA1", Parse.SHA1Hash());
-	 else
-	    ExpectedHash = HashString("MD5Sum", Parse.MD5Hash());
-      }
-      else
-      {
-	 string Hash;
-	 if ((Hash = Parse.SHA512Hash()).empty() == false)
-	    ExpectedHash = HashString("SHA512", Hash);
-	 else if ((Hash = Parse.SHA256Hash()).empty() == false)
-	    ExpectedHash = HashString("SHA256", Hash);
-	 else if ((Hash = Parse.SHA1Hash()).empty() == false)
-	    ExpectedHash = HashString("SHA1", Hash);
-	 else
-	    ExpectedHash = HashString("MD5Sum", Parse.MD5Hash());
-      }
+      ExpectedHashes = Parse.Hashes();
+
       if (PkgFile.empty() == true)
 	 return _error->Error(_("The package index files are corrupted. No Filename: "
 			      "field for package %s."),
@@ -2134,10 +2121,10 @@ bool pkgAcqArchive::QueueNext()
 // AcqArchive::Done - Finished fetching					/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void pkgAcqArchive::Done(string Message,unsigned long long Size,string CalcHash,
+void pkgAcqArchive::Done(string Message,unsigned long long Size, HashStringList const &CalcHashes,
 			 pkgAcquire::MethodConfig *Cfg)
 {
-   Item::Done(Message,Size,CalcHash,Cfg);
+   Item::Done(Message, Size, CalcHashes, Cfg);
    
    // Check the size
    if (Size != Version->Size)
@@ -2145,12 +2132,12 @@ void pkgAcqArchive::Done(string Message,unsigned long long Size,string CalcHash,
       RenameOnError(SizeMismatch);
       return;
    }
-   
-   // Check the hash
+
    // FIXME: could this empty() check impose *any* sort of security issue?
-   if(ExpectedHash.empty() == false && ExpectedHash.toStr() != CalcHash)
+   if(ExpectedHashes.usable() && ExpectedHashes != CalcHashes)
    {
       RenameOnError(HashSumMismatch);
+      printHashSumComparision(DestFile, ExpectedHashes, CalcHashes);
       return;
    }
 
@@ -2222,7 +2209,7 @@ void pkgAcqArchive::Failed(string Message,pkgAcquire::MethodConfig *Cnf)
 									/*}}}*/
 // AcqArchive::IsTrusted - Determine whether this archive comes from a trusted source /*{{{*/
 // ---------------------------------------------------------------------
-APT_PURE bool pkgAcqArchive::IsTrusted()
+APT_PURE bool pkgAcqArchive::IsTrusted() const
 {
    return Trusted;
 }
@@ -2241,11 +2228,11 @@ void pkgAcqArchive::Finished()
 // AcqFile::pkgAcqFile - Constructor					/*{{{*/
 // ---------------------------------------------------------------------
 /* The file is added to the queue */
-pkgAcqFile::pkgAcqFile(pkgAcquire *Owner,string URI,string Hash,
+pkgAcqFile::pkgAcqFile(pkgAcquire *Owner,string URI, HashStringList const &Hashes,
 		       unsigned long long Size,string Dsc,string ShortDesc,
 		       const string &DestDir, const string &DestFilename,
                        bool IsIndexFile) :
-                       Item(Owner), ExpectedHash(Hash), IsIndexFile(IsIndexFile)
+                       Item(Owner), ExpectedHashes(Hashes), IsIndexFile(IsIndexFile)
 {
    Retries = _config->FindI("Acquire::Retries",0);
    
@@ -2282,15 +2269,16 @@ pkgAcqFile::pkgAcqFile(pkgAcquire *Owner,string URI,string Hash,
 // AcqFile::Done - Item downloaded OK					/*{{{*/
 // ---------------------------------------------------------------------
 /* */
-void pkgAcqFile::Done(string Message,unsigned long long Size,string CalcHash,
+void pkgAcqFile::Done(string Message,unsigned long long Size,HashStringList const &CalcHashes,
 		      pkgAcquire::MethodConfig *Cnf)
 {
-   Item::Done(Message,Size,CalcHash,Cnf);
+   Item::Done(Message,Size,CalcHashes,Cnf);
 
    // Check the hash
-   if(!ExpectedHash.empty() && ExpectedHash.toStr() != CalcHash)
+   if(ExpectedHashes.usable() && ExpectedHashes != CalcHashes)
    {
       RenameOnError(HashSumMismatch);
+      printHashSumComparision(DestFile, ExpectedHashes, CalcHashes);
       return;
    }
    
@@ -2361,7 +2349,7 @@ void pkgAcqFile::Failed(string Message,pkgAcquire::MethodConfig *Cnf)
 // AcqIndex::Custom600Headers - Insert custom request headers		/*{{{*/
 // ---------------------------------------------------------------------
 /* The only header we use is the last-modified header. */
-string pkgAcqFile::Custom600Headers()
+string pkgAcqFile::Custom600Headers() const
 {
    if (IsIndexFile)
       return "\nIndex-File: true";