Adding upstream version 2.2.4.upstream/2.2.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 274 insertions, 0 deletions

diff --git a/apt-pkg/deb/debfile.cc b/apt-pkg/deb/debfile.cc
new file mode 100644
index 0000000..645a579
--- /dev/null
+++ b/apt-pkg/deb/debfile.cc
@@ -0,0 +1,274 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+
+   Debian Archive File (.deb)
+   
+   .DEB archives are AR files containing two tars and an empty marker
+   member called 'debian-binary'. The two tars contain the meta data and
+   the actual archive contents. Thus this class is a very simple wrapper
+   around ar/tar to simply extract the right tar files.
+   
+   It also uses the deb package list parser to parse the control file 
+   into the cache.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#include <config.h>
+
+#include <apt-pkg/aptconfiguration.h>
+#include <apt-pkg/arfile.h>
+#include <apt-pkg/debfile.h>
+#include <apt-pkg/dirstream.h>
+#include <apt-pkg/error.h>
+#include <apt-pkg/extracttar.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/strutl.h>
+#include <apt-pkg/tagfile.h>
+
+#include <algorithm>
+#include <string>
+#include <sstream>
+#include <vector>
+#include <string.h>
+#include <sys/stat.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+// DebFile::debDebFile - Constructor					/*{{{*/
+// ---------------------------------------------------------------------
+/* Open the AR file and check for consistency */
+debDebFile::debDebFile(FileFd &File) : File(File), AR(File)
+{
+   if (_error->PendingError() == true)
+      return;
+
+   if (!CheckMember("debian-binary")) {
+      _error->Error(_("This is not a valid DEB archive, missing '%s' member"), "debian-binary");
+      return;
+   }
+
+   if (!CheckMember("control.tar") &&
+       !CheckMember("control.tar.gz") &&
+       !CheckMember("control.tar.xz") &&
+       !CheckMember("control.tar.zst"))
+   {
+      _error->Error(_("This is not a valid DEB archive, missing '%s' member"), "control.tar");
+      return;
+   }
+
+   if (!CheckMember("data.tar") &&
+       !CheckMember("data.tar.gz") &&
+       !CheckMember("data.tar.bz2") &&
+       !CheckMember("data.tar.lzma") &&
+       !CheckMember("data.tar.xz") &&
+       !CheckMember("data.tar.zst"))
+   {
+      _error->Error(_("This is not a valid DEB archive, missing '%s' member"), "data.tar");
+      return;
+   }
+}
+									/*}}}*/
+// DebFile::CheckMember - Check if a named member is in the archive	/*{{{*/
+// ---------------------------------------------------------------------
+/* This is used to check for a correct deb and to give nicer error messages
+   for people playing around. */
+bool debDebFile::CheckMember(const char *Name)
+{
+   if (AR.FindMember(Name) == 0)
+      return false;
+   return true;
+}
+									/*}}}*/
+// DebFile::GotoMember - Jump to a Member				/*{{{*/
+// ---------------------------------------------------------------------
+/* Jump in the file to the start of a named member and return the information
+   about that member. The caller can then read from the file up to the 
+   returned size. Note, since this relies on the file position this is
+   a destructive operation, it also changes the last returned Member
+   structure - so don't nest them! */
+const ARArchive::Member *debDebFile::GotoMember(const char *Name)
+{
+   // Get the archive member and positition the file
+   const ARArchive::Member *Member = AR.FindMember(Name);
+   if (Member == 0)
+   {
+      return 0;
+   }
+   if (File.Seek(Member->Start) == false)
+      return 0;
+      
+   return Member;
+}
+									/*}}}*/
+// DebFile::ExtractTarMember - Extract the contents of a tar member	/*{{{*/
+// ---------------------------------------------------------------------
+/* Simple wrapper around tar.. */
+bool debDebFile::ExtractTarMember(pkgDirStream &Stream,const char *Name)
+{
+   std::string Compressor;
+   auto const Compressors = APT::Configuration::getCompressors();
+
+   ARArchive::Member const *Member = AR.FindMember(Name);
+   if (Member != nullptr)
+   {
+      auto const found = std::find_if(Compressors.cbegin(), Compressors.cend(), [&](auto const &c) {
+	 return not c.Extension.empty() && APT::String::Endswith(Name, c.Extension);
+      });
+      if (found != Compressors.cend())
+	 Compressor = found->Name;
+   }
+   else
+   {
+      for (auto const &c : Compressors)
+      {
+	 if (c.Extension.empty())
+	    continue;
+	 Member = AR.FindMember(std::string(Name).append(c.Extension).c_str());
+	 if (Member == nullptr)
+	    continue;
+	 Compressor = c.Name;
+	 break;
+      }
+   }
+
+   if (Member == nullptr)
+   {
+      std::ostringstream ext;
+      ext << Name << '{';
+      for (auto const &c : Compressors)
+	 if (not c.Extension.empty())
+	    ext << c.Extension << ',';
+      ext << '}';
+      return _error->Error(_("Internal error, could not locate member %s"), ext.str().c_str());
+   }
+
+   if (not File.Seek(Member->Start))
+      return false;
+
+   ExtractTar Tar(File,Member->Size,Compressor);
+   if (_error->PendingError())
+      return false;
+   return Tar.Go(Stream);
+}
+									/*}}}*/
+// DebFile::ExtractArchive - Extract the archive data itself		/*{{{*/
+// ---------------------------------------------------------------------
+/* Simple wrapper around DebFile::ExtractTarMember. */
+bool debDebFile::ExtractArchive(pkgDirStream &Stream)
+{
+   return ExtractTarMember(Stream, "data.tar");
+}
+									/*}}}*/
+
+// DebFile::ControlExtract::DoItem - Control Tar Extraction		/*{{{*/
+// ---------------------------------------------------------------------
+/* This directory stream handler for the control tar handles extracting
+   it into the temporary meta directory. It only extracts files, it does
+   not create directories, links or anything else. */
+bool debDebFile::ControlExtract::DoItem(Item &Itm,int &Fd)
+{
+   if (Itm.Type != Item::File)
+      return true;
+   
+   /* Cleanse the file name, prevent people from trying to unpack into
+      absolute paths, .., etc */
+   for (char *I = Itm.Name; *I != 0; I++)
+      if (*I == '/')
+	 *I = '_';
+
+   /* Force the ownership to be root and ensure correct permissions, 
+      go-w, the rest are left untouched */
+   Itm.UID = 0;
+   Itm.GID = 0;
+   Itm.Mode &= ~(S_IWGRP | S_IWOTH);
+   
+   return pkgDirStream::DoItem(Itm,Fd);
+}
+									/*}}}*/
+
+// MemControlExtract::DoItem - Check if it is the control file		/*{{{*/
+// ---------------------------------------------------------------------
+/* This sets up to extract the control block member file into a memory 
+   block of just the right size. All other files go into the bit bucket. */
+
+// Upper size limit for control files. Two reasons for having a limit here:
+//
+// 1. We read those files into memory and want to avoid being killed by OOM
+//
+// 2. We allocate (Itm.Size+2)-large arrays, so this can overflow if Itm.Size
+// becomes 2**64-2 or larger. This is obviously
+//
+// 64 MiB seems like a terribly large size that everyone should be happy with.
+static const unsigned long long DEB_CONTROL_SIZE_LIMIT = 64 * 1024 * 1024;
+bool debDebFile::MemControlExtract::DoItem(Item &Itm,int &Fd)
+{
+   // At the control file, allocate buffer memory.
+   if (Member == Itm.Name)
+   {
+      if (Itm.Size > DEB_CONTROL_SIZE_LIMIT)
+	 return _error->Error("Control file too large: %llu > %llu bytes", Itm.Size, DEB_CONTROL_SIZE_LIMIT);
+      delete [] Control;
+      Control = new char[Itm.Size+2];
+      IsControl = true;
+      Fd = -2; // Signal to pass to Process
+      Length = Itm.Size;
+   }   
+   else
+      IsControl = false;
+   
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::Process - Process extracting the control file	/*{{{*/
+// ---------------------------------------------------------------------
+/* Just memcopy the block from the tar extractor and put it in the right
+   place in the pre-allocated memory block. */
+bool debDebFile::MemControlExtract::Process(Item &/*Itm*/,const unsigned char *Data,
+			     unsigned long long Size,unsigned long long Pos)
+{
+   memcpy(Control + Pos, Data,Size);
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::Read - Read the control information from the deb	/*{{{*/
+// ---------------------------------------------------------------------
+/* This uses the internal tar extractor to fetch the control file, and then
+   it parses it into a tag section parser. */
+bool debDebFile::MemControlExtract::Read(debDebFile &Deb)
+{
+   if (Deb.ExtractTarMember(*this, "control.tar") == false)
+      return false;
+
+   if (Control == 0)
+      return true;
+   
+   Control[Length] = '\n';
+   Control[Length+1] = '\n';
+   if (Section.Scan(Control,Length+2) == false)
+      return _error->Error(_("Unparsable control file"));
+   return true;
+}
+									/*}}}*/
+// MemControlExtract::TakeControl - Parse a memory block		/*{{{*/
+// ---------------------------------------------------------------------
+/* The given memory block is loaded into the parser and parsed as a control
+   record. */
+bool debDebFile::MemControlExtract::TakeControl(const void *Data,unsigned long long Size)
+{
+   if (Size > DEB_CONTROL_SIZE_LIMIT)
+      return _error->Error("Control file too large: %llu > %llu bytes", Size, DEB_CONTROL_SIZE_LIMIT);
+
+   delete [] Control;
+   Control = new char[Size+2];
+   Length = Size;
+   memcpy(Control,Data,Size);
+   
+   Control[Length] = '\n';
+   Control[Length+1] = '\n';
+   return Section.Scan(Control,Length+2);
+}
+									/*}}}*/
+