2 files changed, 22 insertions, 0 deletions
diff --git a/apt-pkg/contrib/fileutl.cc b/apt-pkg/contrib/fileutl.cc
index 29450ada0..6b8f04dea 100644
--- a/apt-pkg/contrib/fileutl.cc
+++ b/apt-pkg/contrib/fileutl.cc
@@ -47,6 +47,7 @@
 #include <signal.h>
 #include <errno.h>
 #include <glob.h>
+#include <pwd.h>
 
 #include <set>
 #include <algorithm>
@@ -2166,3 +2167,20 @@ bool Popen(const char* Args[], FileFd &Fd, pid_t &Child, FileFd::OpenMode Mode)
 
    return true;
 }
+
+bool DropPrivs()
+{
+   if (getuid() != 0)
+      return true;
+
+   const std::string nobody = _config->Find("APT::User::Nobody", "nobody");
+   struct passwd *pw = getpwnam(nobody.c_str());
+   if (pw == NULL)
+      return _error->Warning("No user %s, can not drop rights", nobody.c_str());
+   if (setgid(pw->pw_gid) != 0)
+      return _error->Errno("setgid", "Failed to setgid");
+   if (setuid(pw->pw_uid) != 0)
+      return _error->Errno("setuid", "Failed to setuid");
+
+   return true;
+}
diff --git a/apt-pkg/contrib/fileutl.h b/apt-pkg/contrib/fileutl.h
index 0b4d94885..e04f75e2a 100644
--- a/apt-pkg/contrib/fileutl.h
+++ b/apt-pkg/contrib/fileutl.h
@@ -193,9 +193,13 @@ pid_t ExecFork(std::set<int> keep_fds);
 void MergeKeepFdsFromConfiguration(std::set<int> &keep_fds);
 bool ExecWait(pid_t Pid,const char *Name,bool Reap = false);
 
+
 // check if the given file starts with a PGP cleartext signature
 bool StartsWithGPGClearTextSignature(std::string const &FileName);
 
+// process releated
+bool DropPrivs();
+
 // File string manipulators
 std::string flNotDir(std::string File);
 std::string flNotFile(std::string File);