Merge pull request #7820 from pieterlexis/systemd-no-setuid

[thirdparty/pdns.git] / pdns / dnsdist.cc

diff --git a/pdns/dnsdist.cc b/pdns/dnsdist.cc
index 7c584c0e993b32e2a1607192d0bedccf40a815e6..7e93aa67702bbfaa48356f83852d68910c7940d8 100644 (file)
--- a/pdns/dnsdist.cc
+++ b/pdns/dnsdist.cc
@@ -37,6 +37,7 @@
 #include <editline/readline.h>
 #endif
 
+#include "dnsdist-systemd.hh"
 #ifdef HAVE_SYSTEMD
 #include <systemd/sd-daemon.h>
 #endif
@@ -1536,7 +1537,7 @@ ProcessQueryResult processQuery(DNSQuestion& dq, ClientState& cs, LocalHolders&
         }
       }
 
-      if (!handleEDNSClientSubnet(dq, &(dq.ednsAdded), &(dq.ecsAdded), g_preserveTrailingData)) {
+      if (!handleEDNSClientSubnet(dq, dq.ednsAdded, dq.ecsAdded, g_preserveTrailingData)) {
         vinfolog("Dropping query from %s because we couldn't insert the ECS value", dq.remote->toStringWithPort());
         return ProcessQueryResult::Drop;
       }
@@ -2590,8 +2591,8 @@ try
   }
 #endif
 
-  uid_t newgid=0;
-  gid_t newuid=0;
+  uid_t newgid=getegid();
+  gid_t newuid=geteuid();
 
   if(!g_cmdLine.gid.empty())
     newgid = strToGID(g_cmdLine.gid.c_str());
@@ -2599,8 +2600,22 @@ try
   if(!g_cmdLine.uid.empty())
     newuid = strToUID(g_cmdLine.uid.c_str());
 
-  dropGroupPrivs(newgid);
-  dropUserPrivs(newuid);
+  if (getegid() != newgid) {
+    if (running_in_service_mgr()) {
+      errlog("--gid/-g set on command-line, but dnsdist was started as a systemd service. Use the 'Group' setting in the systemd unit file to set the group to run as");
+      _exit(EXIT_FAILURE);
+    }
+    dropGroupPrivs(newgid);
+  }
+
+  if (geteuid() != newuid) {
+    if (running_in_service_mgr()) {
+      errlog("--uid/-u set on command-line, but dnsdist was started as a systemd service. Use the 'User' setting in the systemd unit file to set the user to run as");
+      _exit(EXIT_FAILURE);
+    }
+    dropUserPrivs(newuid);
+  }
+
   try {
     /* we might still have capabilities remaining,
        for example if we have been started as root