From be57b91ba175ff5f48919472f4a9b1841bc41d96 Mon Sep 17 00:00:00 2001
From: Joshua Kwan <joshk@triplehelix.org>
Date: Wed, 21 Jan 2004 01:37:16 +0000
Subject: [PATCH] Additional anti-root uid security fixes

git-svn-id: svn://katsu.triplehelix.org/dgamelaunch/trunk@134 db0b04b0-f4d1-0310-9a6d-de3e77497b0e
---
 config.y      | 29 ++++++++++++++++++++++++++---
 dgamelaunch.c |  4 ++--
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/config.y b/config.y
index 336f144..485cd11 100644
--- a/config.y
+++ b/config.y
@@ -45,7 +45,11 @@ KeyPair: KeyType '=' TYPE_VALUE {
   struct passwd* usr;
   
   if (!myconfig)
+  {
     myconfig = calloc(1, sizeof(struct dg_config));
+    myconfig->shed_uid = (uid_t)-1;
+    myconfig->shed_gid = (gid_t)-1;
+  }
 
   switch ($1)
   {
@@ -58,12 +62,25 @@ KeyPair: KeyType '=' TYPE_VALUE {
       
       break;
     case TYPE_SUSER:
+      if (!strcmp($3, "root"))
+      {
+        fprintf(stderr, "%s: I refuse to run as root! Aborting.\n", config);
+	graceful_exit(1);
+      }
       myconfig->shed_user = strdup($3);
       if ((usr = getpwnam($3)) != NULL)
-        myconfig->shed_uid = usr->pw_uid;
+      {
+        if (usr->pw_uid != 0)
+          myconfig->shed_uid = usr->pw_uid;
+	else
+	{
+	  fprintf(stderr, "%s: I refuse to run as %s (uid 0!) Aborting.\n", config, $3);
+	  graceful_exit(1);
+	}
+      }
       else
-        fprintf(stderr, "%s: no such group '%s'\n", config, $3);
-     break;
+        fprintf(stderr, "%s: no such user '%s'\n", config, $3);
+      break;
 
     case TYPE_PATH_CHROOT:
       if (myconfig->chroot) free(myconfig->chroot);
@@ -113,6 +130,12 @@ KeyPair: KeyType '=' TYPE_VALUE {
     case TYPE_SUID:
       if (!myconfig->shed_user)
       {
+        /* Naive user protection - do not allow running as user root */
+	if ($3 == 0)
+	{
+	  fprintf(stderr, "%s: I refuse to run as root! Aborting.\n", config);
+	  graceful_exit(1);
+	}
         myconfig->shed_uid = $3;
       }
 	
diff --git a/dgamelaunch.c b/dgamelaunch.c
index 958a372..f056607 100644
--- a/dgamelaunch.c
+++ b/dgamelaunch.c
@@ -170,7 +170,7 @@ create_config ()
     }
 
     /* Fill the rest with defaults */
-    if (!myconfig->shed_user && myconfig->shed_uid == 0)
+    if (!myconfig->shed_user && myconfig->shed_uid == -1)
     {
       struct passwd *pw;
       if ((pw = getpwnam(defconfig.shed_user)))
@@ -179,7 +179,7 @@ create_config ()
 	myconfig->shed_uid = defconfig.shed_uid;
     }
 
-    if (!myconfig->shed_group && myconfig->shed_gid == 0)
+    if (!myconfig->shed_group && myconfig->shed_gid == -1)
     {
       struct group *gr;
       if ((gr = getgrnam(defconfig.shed_group)))
-- 
2.47.3