Merge commit '86cc97e55fe346502462284d2e636a2b3708163e' as 'Sources/OpenVPN3'

2026-04-24 00:00:05 +08:00 · 2020-02-24 14:43:11 +03:00
parent 133b3756e6 86cc97e55f
commit 32f1555929
655 changed files with 146468 additions and 0 deletions
@@ -0,0 +1,195 @@
+//    OpenVPN -- An application to securely tunnel IP networks
+//               over a single port, with support for SSL/TLS-based
+//               session authentication and key exchange,
+//               packet encryption, packet authentication, and
+//               packet compression.
+//
+//    Copyright (C) 2012-2017 OpenVPN Inc.
+//
+//    This program is free software: you can redistribute it and/or modify
+//    it under the terms of the GNU Affero General Public License Version 3
+//    as published by the Free Software Foundation.
+//
+//    This program is distributed in the hope that it will be useful,
+//    but WITHOUT ANY WARRANTY; without even the implied warranty of
+//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//    GNU Affero General Public License for more details.
+//
+//    You should have received a copy of the GNU Affero General Public License
+//    along with this program in the COPYING file.
+//    If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef OPENVPN_COMMON_USERGROUP_H
+#define OPENVPN_COMMON_USERGROUP_H
+
+#include <pwd.h>
+#include <grp.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <errno.h>
+
+#include <string>
+
+#include <openvpn/common/platform.hpp>
+
+#ifdef OPENVPN_PLATFORM_LINUX
+#include <sys/prctl.h>
+#endif
+
+#include <openvpn/common/size.hpp>
+#include <openvpn/common/exception.hpp>
+#include <openvpn/common/to_string.hpp>
+#include <openvpn/common/strerror.hpp>
+
+namespace openvpn {
+  // NOTE: -- SetUserGroup object does not own passwd and group
+  // objects, therefore *pw and *gr can change under us.
+  class SetUserGroup
+  {
+  public:
+    OPENVPN_EXCEPTION(user_group_err);
+
+    SetUserGroup(const std::string& user, const std::string& group, const bool strict)
+      : SetUserGroup(user.empty() ? nullptr : user.c_str(),
+		     group.empty() ? nullptr : group.c_str(),
+		     strict)
+    {
+    }
+
+    SetUserGroup(const char *user, const char *group, const bool strict)
+      : pw(nullptr),
+	gr(nullptr)
+    {
+      if (user)
+	{
+	  pw = ::getpwnam(user);
+	  if (!pw && strict)
+	    OPENVPN_THROW(user_group_err, "user lookup failed for '" << user << '\'');
+	  user_name = user;
+	}
+      if (group)
+	{
+	  gr = ::getgrnam(group);
+	  if (!gr && strict)
+	    OPENVPN_THROW(user_group_err, "group lookup failed for '" << group << '\'');
+	  group_name = group;
+	}
+    }
+
+    const std::string& user() const
+    {
+      return user_name;
+    }
+
+    const std::string& group() const
+    {
+      return group_name;
+    }
+
+    void activate() const
+    {
+      if (gr)
+	{
+	  if (::setgid(gr->gr_gid))
+	    {
+	      const int eno = errno;
+	      OPENVPN_THROW(user_group_err, "setgid failed for group '" << group_name << "': " << strerror_str(eno));
+	    }
+	  gid_t gr_list[1];
+	  gr_list[0] = gr->gr_gid;
+	  if (::setgroups(1, gr_list))
+	    {
+	      const int eno = errno;
+	      OPENVPN_THROW(user_group_err, "setgroups failed for group '" << group_name << "': " << strerror_str(eno));
+	    }
+	  OPENVPN_LOG("GID set to '" << group_name << '\'');
+	}
+      if (pw)
+	{
+	  if (::setuid(pw->pw_uid))
+	    {
+	      const int eno = errno;
+	      OPENVPN_THROW(user_group_err, "setuid failed for user '" << user_name << "': " << strerror_str(eno));
+	    }
+	  OPENVPN_LOG("UID set to '" << user_name << '\'');
+	}
+#ifdef OPENVPN_PLATFORM_LINUX
+      // retain core dumpability after setgid/setuid
+      if (gr || pw)
+	::prctl(PR_SET_DUMPABLE, 1);
+#endif
+    }
+
+    void chown(const std::string& fn) const
+    {
+      if (pw && gr)
+	{
+	  const int status = ::chown(fn.c_str(), uid(), gid());
+	  if (status < 0)
+	    {
+	      const int eno = errno;
+	      OPENVPN_THROW(user_group_err, "chown " << user_name << '.' << group_name << ' ' << fn << " : " << strerror_str(eno));
+	    }
+	}
+    }
+
+    void chown(const int fd, const std::string& title) const
+    {
+      if (pw && gr)
+	{
+	  const int status = ::fchown(fd, uid(), gid());
+	  if (status < 0)
+	    {
+	      const int eno = errno;
+	      OPENVPN_THROW(user_group_err, "chown " << user_name << '.' << group_name << ' ' << title << " : " << strerror_str(eno));
+	    }
+	}
+    }
+
+    void invalidate()
+    {
+      pw = nullptr;
+      gr = nullptr;
+    }
+
+    uid_t uid() const
+    {
+      if (pw)
+	return pw->pw_uid;
+      else
+	return -1;
+    }
+
+    gid_t gid() const
+    {
+      if (gr)
+	return gr->gr_gid;
+      else
+	return -1;
+    }
+
+    bool uid_defined() const
+    {
+      return bool(pw);
+    }
+
+    bool gid_defined() const
+    {
+      return bool(gr);
+    }
+
+    bool defined() const
+    {
+      return uid_defined() && gid_defined();
+    }
+
+  private:
+    std::string user_name;
+    std::string group_name;
+
+    struct passwd *pw;
+    struct group *gr;
+  };
+}
+
+#endif