* syscalls.cc (seteuid): Do not take allow_ntsec into account.

Attempt to use an existing or new token even when the uid
	matches orig_uid, but the gid is not in the process token.
	Major reorganization after several incremental changes.
	(setegid): Do not take allow_ntsec into account. Minor
	reorganization after several incremental changes.

winsup/cygwin/ChangeLog

@@ -1,3 +1,12 @@
+2002-05-22  Pierre Humblet <pierre.humblet@ieee.org>
+
+	* syscalls.cc (seteuid): Do not take allow_ntsec into account.
+	Attempt to use an existing or new token even when the uid
+	matches orig_uid, but the gid is not in the process token.
+	Major reorganization after several incremental changes.
+	(setegid): Do not take allow_ntsec into account. Minor
+	reorganization after several incremental changes.
+
 2002-05-26  Christopher Faylor  <cgf@redhat.com>
 
 	* debug.h (being_debugged): New macro.

winsup/cygwin/syscalls.cc

@@ -1938,250 +1938,229 @@ extern struct passwd *internal_getlogin (cygheap_user &user);
 extern "C" int
 seteuid (__uid16_t uid)
 {
-  sigframe thisframe (mainthread);
+  if (!wincap.has_security ()) return 0;
-  if (wincap.has_security ())
+
+  if (uid == ILLEGAL_UID)
     {
+      debug_printf ("new euid == illegal euid, nothing happens");
+      return 0;
+    }
+
+  sigframe thisframe (mainthread);
+  DWORD ulen = UNLEN + 1;
+  DWORD dlen = INTERNET_MAX_HOST_NAME_LENGTH + 1;
   char orig_username[UNLEN + 1];
   char orig_domain[INTERNET_MAX_HOST_NAME_LENGTH + 1];
   char username[UNLEN + 1];
-      DWORD ulen = UNLEN + 1;
   char domain[INTERNET_MAX_HOST_NAME_LENGTH + 1];
-      DWORD dlen = INTERNET_MAX_HOST_NAME_LENGTH + 1;
+  cygsid usersid, pgrpsid;
-      SID_NAME_USE use;
+  HANDLE ptok, sav_token;
+  BOOL sav_impersonated, sav_token_is_internal_token;
+  BOOL process_ok, explicitly_created_token = FALSE;
+  struct passwd * pw_new, * pw_cur;
+  cygheap_user user;
+  PSID origpsid, psid2 = NO_SID;
 
-      if (uid == ILLEGAL_UID || uid == myself->uid)
+  debug_printf ("uid: %d myself->gid: %d", uid, myself->gid);
-	{
+
-	  debug_printf ("new euid == current euid, nothing happens");
+  pw_new = getpwuid (uid);
-	  return 0;
+  if (!usersid.getfrompw (pw_new) ||
-	}
+      (!pgrpsid.getfromgr (getgrgid (myself->gid))))
-      struct passwd *pw_new = getpwuid (uid);
-      if (!pw_new)
     {
       set_errno (EINVAL);
       return -1;
     }
-
+  /* Save current information */
-      cygsid tok_usersid;
+  sav_token = cygheap->user.token;
-      DWORD siz;
+  sav_impersonated = cygheap->user.impersonated;
-
   char *env;
   orig_username[0] = orig_domain[0] = '\0';
   if ((env = getenv ("USERNAME")))
-	strncat (orig_username, env, UNLEN + 1);
+    strlcpy (orig_username, env, sizeof(orig_username));
   if ((env = getenv ("USERDOMAIN")))
-	strncat (orig_domain, env, INTERNET_MAX_HOST_NAME_LENGTH + 1);
+    strlcpy (orig_domain, env, sizeof(orig_domain));
-      if (uid == cygheap->user.orig_uid)
-	{
 
-	  debug_printf ("RevertToSelf () (uid == orig_uid, token=%d)",
-			cygheap->user.token);
   RevertToSelf();
-	  if (cygheap->user.token != INVALID_HANDLE_VALUE)
+  if (!OpenProcessToken (GetCurrentProcess (),
-	    cygheap->user.impersonated = FALSE;
+			 TOKEN_QUERY | TOKEN_ADJUST_DEFAULT, &ptok))
-
-	  HANDLE ptok = INVALID_HANDLE_VALUE;
-	  if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &ptok))
-	    debug_printf ("OpenProcessToken(): %E\n");
-	  else if (!GetTokenInformation (ptok, TokenUser, &tok_usersid,
-					 sizeof tok_usersid, &siz))
-	    debug_printf ("GetTokenInformation(): %E");
-	  else if (!LookupAccountSid (NULL, tok_usersid, username, &ulen,
-				      domain, &dlen, &use))
-	    debug_printf ("LookupAccountSid(): %E");
-	  else
     {
-	      setenv ("USERNAME", username, 1);
+      __seterrno ();
-	      setenv ("USERDOMAIN", domain, 1);
+      goto failed;
     }
-	  if (ptok != INVALID_HANDLE_VALUE)
+  /* Verify if the process token is suitable.
-	    CloseHandle (ptok);
+     Currently we do not try to differentiate between
-	}
+	 internal tokens and others */
-      else
+  process_ok = verify_token(ptok, usersid, pgrpsid);
+  debug_printf("Process token %sverified", process_ok?"":"not ");
+  if (process_ok)
     {
-	  cygsid usersid, pgrpsid, origsid;
+      if (cygheap->user.token == INVALID_HANDLE_VALUE ||
-	  HANDLE sav_token = INVALID_HANDLE_VALUE;
-	  BOOL sav_impersonation;
-	  BOOL current_token_is_internal_token = FALSE;
-	  BOOL explicitely_created_token = FALSE;
-
-	  struct __group16 *gr = getgrgid (myself->gid);
-	  debug_printf ("myself->gid: %d, gr: %d", myself->gid, gr);
-
-	  usersid.getfrompw (pw_new);
-	  pgrpsid.getfromgr (gr);
-
-	  /* Only when ntsec is ON! */
-	  /* Check if new user == user of impersonation token and
-	     - if reasonable - new pgrp == pgrp of impersonation token. */
-	  if (allow_ntsec && cygheap->user.token != INVALID_HANDLE_VALUE)
-	    {
-	      if (!verify_token(cygheap->user.token, usersid, pgrpsid,
-				& current_token_is_internal_token))
-		{
-		  /* If not, RevertToSelf and close old token. */
-		  debug_printf ("tsid != usersid");
-		  RevertToSelf ();
-		  sav_token = cygheap->user.token;
-		  sav_impersonation = cygheap->user.impersonated;
-		  cygheap->user.token = INVALID_HANDLE_VALUE;
-		  cygheap->user.impersonated = FALSE;
-		}
-	    }
-
-	  /* Only when ntsec is ON! */
-	  /* If no impersonation token is available, try to
-	     authenticate using NtCreateToken() or subauthentication. */
-	  if (allow_ntsec && cygheap->user.token == INVALID_HANDLE_VALUE)
-	    {
-	      HANDLE ptok = INVALID_HANDLE_VALUE;
-
-	      ptok = create_token (usersid, pgrpsid);
-	      if (ptok != INVALID_HANDLE_VALUE)
-		explicitely_created_token = TRUE;
-	      else
-		{
-		  /* create_token failed. Try subauthentication. */
-		  debug_printf ("create token failed, try subauthentication.");
-		  ptok = subauth (pw_new);
-		}
-	      if (ptok != INVALID_HANDLE_VALUE)
-		{
-		  cygwin_set_impersonation_token (ptok);
-		  /* If sav_token was internally created, destroy it. */
-		  if (sav_token != INVALID_HANDLE_VALUE &&
-		      current_token_is_internal_token)
-		    CloseHandle (sav_token);
-		}
-	      else if (sav_token != INVALID_HANDLE_VALUE)
-		cygheap->user.token = sav_token;
-	    }
-	  /* If no impersonation is active but an impersonation
-	     token is available, try to impersonate. */
-	  if (cygheap->user.token != INVALID_HANDLE_VALUE &&
 	  ! cygheap->user.impersonated )
         {
-	      debug_printf ("Impersonate (uid == %d)", uid);
+	  CloseHandle (ptok);
-	      RevertToSelf ();
+	  return 0; /* No change */
-
-	      /* If the token was explicitely created, all information has
-		 already been set correctly. */
-	      if (!explicitely_created_token)
-		{
-		  /* Try setting owner to same value as user. */
-		  if (usersid &&
-		      !SetTokenInformation (cygheap->user.token, TokenOwner,
-					    &usersid, sizeof usersid))
-		    debug_printf ("SetTokenInformation(user.token, "
-				  "TokenOwner): %E");
-		  /* Try setting primary group in token to current group
-		     if token not explicitely created. */
-		  if (pgrpsid &&
-		      !SetTokenInformation (cygheap->user.token,
-					    TokenPrimaryGroup,
-					    &pgrpsid, sizeof pgrpsid))
-		    debug_printf ("SetTokenInformation(user.token, "
-				  "TokenPrimaryGroup): %E");
 	}
+      else cygheap->user.impersonated = FALSE;
+    }
+
+  if (!process_ok && cygheap->user.token != INVALID_HANDLE_VALUE)
+    {
+      /* Verify if the current tokem is suitable */
+      BOOL token_ok = verify_token (cygheap->user.token, usersid, pgrpsid,
+				    & sav_token_is_internal_token);
+      debug_printf("Thread token %d %sverified",
+		   cygheap->user.token, token_ok?"":"not ");
+      if (token_ok)
+        {
+	  /* Return if current token is valid */
+	  if (cygheap->user.impersonated)
+	  {
+	    CloseHandle (ptok);
+	    if (!ImpersonateLoggedOnUser (cygheap->user.token))
+	      system_printf ("Impersonating in seteuid failed: %E");
+	    return 0; /* No change */
+	  }
+	}
+      else cygheap->user.token = INVALID_HANDLE_VALUE;
+    }
+
   /* Set process def dacl to allow access to impersonated token */
   char dacl_buf[MAX_DACL_LEN(5)];
-	      origsid = cygheap->user.orig_sid ();
+  if (usersid != (origpsid =  cygheap->user.orig_sid())) psid2 = usersid;
-	      if (usersid && origsid &&
+  if (sec_acl ((PACL) dacl_buf, FALSE, origpsid, psid2))
-		  sec_acl((PACL) dacl_buf, FALSE, origsid, usersid))
     {
-		  HANDLE ptok = INVALID_HANDLE_VALUE;
       TOKEN_DEFAULT_DACL tdacl;
       tdacl.DefaultDacl = (PACL) dacl_buf;
-		  if (!OpenProcessToken (GetCurrentProcess (), TOKEN_ADJUST_DEFAULT,
-					 &ptok))
-		    debug_printf ("OpenProcessToken(): %E");
-		  else
-		    {
       if (!SetTokenInformation (ptok, TokenDefaultDacl,
 				&tdacl, sizeof dacl_buf))
 	debug_printf ("SetTokenInformation"
 		      "(TokenDefaultDacl): %E");
     }
-		  if (ptok != INVALID_HANDLE_VALUE) CloseHandle (ptok);
+  CloseHandle (ptok);
-		}
+
-	      /* Now try to impersonate. */
+  if (!process_ok && cygheap->user.token == INVALID_HANDLE_VALUE)
-	      if (!LookupAccountSid (NULL, usersid, username, &ulen,
+    {
-				     domain, &dlen, &use))
+      /* If no impersonation token is available, try to
-		debug_printf ("LookupAccountSid (): %E");
+	 authenticate using NtCreateToken() or subauthentication. */
-	      else if (!ImpersonateLoggedOnUser (cygheap->user.token))
+      cygheap->user.token = create_token (usersid, pgrpsid);
-		system_printf ("Impersonating (%d) in set(e)uid failed: %E",
+      if (cygheap->user.token != INVALID_HANDLE_VALUE)
-			       cygheap->user.token);
+	explicitly_created_token = TRUE;
       else
         {
-		  cygheap->user.impersonated = TRUE;
+	  /* create_token failed. Try subauthentication. */
-		  setenv ("USERNAME", username, 1);
+	  debug_printf ("create token failed, try subauthentication.");
-		  setenv ("USERDOMAIN", domain, 1);
+	  cygheap->user.token = subauth (pw_new);
-		}
+	  if (cygheap->user.token == INVALID_HANDLE_VALUE) goto failed;
 	}
     }
 
-      cygheap_user user;
+  /* Lookup username and domain before impersonating,
+     LookupAccountSid() returns a different answer afterwards. */
+  SID_NAME_USE use;
+  if (!LookupAccountSid (NULL, usersid, username, &ulen,
+			 domain, &dlen, &use))
+    {
+      debug_printf ("LookupAccountSid (): %E");
+      __seterrno ();
+      goto failed;
+    }
+  /* If using the token, set info and impersonate */
+  if (! process_ok )
+    {
+      /* If the token was explicitly created, all information has
+	 already been set correctly. */
+      if (!explicitly_created_token)
+        {
+	  /* Try setting owner to same value as user. */
+	  if (!SetTokenInformation (cygheap->user.token, TokenOwner,
+				    &usersid, sizeof usersid))
+	    debug_printf ("SetTokenInformation(user.token, "
+			  "TokenOwner): %E");
+	  /* Try setting primary group in token to current group */
+	  if (!SetTokenInformation (cygheap->user.token,
+				    TokenPrimaryGroup,
+				    &pgrpsid, sizeof pgrpsid))
+	    debug_printf ("SetTokenInformation(user.token, "
+			  "TokenPrimaryGroup): %E");
+	}
+      /* Now try to impersonate. */
+      if (!ImpersonateLoggedOnUser (cygheap->user.token))
+        {
+	  debug_printf ("ImpersonateLoggedOnUser %E");
+	  __seterrno ();
+	  goto failed;
+	}
+      cygheap->user.impersonated = TRUE;
+    }
+
   /* user.token is used in internal_getlogin () to determine if
      impersonation is active. If so, the token is used for
      retrieving user's SID. */
   user.token = cygheap->user.impersonated ? cygheap->user.token
                                           : INVALID_HANDLE_VALUE;
-      /* Unsetting these both env vars is necessary to get NetUserGetInfo()
+  /* Unsetting these two env vars is necessary to get NetUserGetInfo()
      called in internal_getlogin ().  Otherwise the wrong path is used
      after a user switch, probably. */
   unsetenv ("HOMEDRIVE");
   unsetenv ("HOMEPATH");
-      struct passwd *pw_cur = internal_getlogin (user);
+  setenv ("USERDOMAIN", domain, 1);
-      if (pw_cur != pw_new)
+  setenv ("USERNAME", username, 1);
+  pw_cur = internal_getlogin (user);
+  if (pw_cur == pw_new)
     {
+      /* If sav_token was internally created and is replaced, destroy it. */
+      if (sav_token != INVALID_HANDLE_VALUE &&
+	  sav_token != cygheap->user.token &&
+	  sav_token_is_internal_token)
+	CloseHandle (sav_token);
+      myself->uid = uid;
+      cygheap->user = user;
+      return 0;
+    }
   debug_printf ("Diffs!!! token: %d, cur: %d, new: %d, orig: %d",
 		cygheap->user.token, pw_cur->pw_uid,
 		pw_new->pw_uid, cygheap->user.orig_uid);
+  set_errno (EPERM);
+
+ failed:
   setenv ("USERNAME", orig_username, 1);
   setenv ("USERDOMAIN", orig_domain, 1);
-	  set_errno (EPERM);
+  cygheap->user.token = sav_token;
+  cygheap->user.impersonated = sav_impersonated;
+  if ( cygheap->user.token != INVALID_HANDLE_VALUE &&
+       cygheap->user.impersonated &&
+       !ImpersonateLoggedOnUser (cygheap->user.token))
+    system_printf ("Impersonating in seteuid failed: %E");
   return -1;
 }
-      myself->uid = uid;
-      cygheap->user = user;
-    }
-  else
-    set_errno (ENOSYS);
-  debug_printf ("real: %d, effective: %d", cygheap->user.real_uid, myself->uid);
-  return 0;
-}
 
 /* setegid: from System V.  */
 extern "C" int
 setegid (__gid16_t gid)
 {
-  sigframe thisframe (mainthread);
+  if ((!wincap.has_security ()) ||
-  if (wincap.has_security ())
+      (gid == ILLEGAL_GID))
-    {
+    return 0;
-      if (gid != ILLEGAL_GID)
-	{
-	  struct __group16 *gr;
 
-	  if (!(gr = getgrgid (gid)))
+  sigframe thisframe (mainthread);
+  cygsid gsid;
+  HANDLE ptok;
+
+  if (!(gsid.getfromgr (getgrgid (gid))))
     {
       set_errno (EINVAL);
       return -1;
     }
   myself->gid = gid;
-	  if (allow_ntsec)
-	    {
-	      cygsid gsid;
-	      HANDLE ptok;
 
-	      if (gsid.getfromgr (gr))
+  /* If impersonated, update primary group and revert */
-		{
-		  /* Remove impersonation */
   if (cygheap->user.token != INVALID_HANDLE_VALUE
       && cygheap->user.impersonated)
     {
       if (!SetTokenInformation (cygheap->user.token,
 				TokenPrimaryGroup,
 				&gsid, sizeof gsid))
-			debug_printf ("SetTokenInformation(primary, "
+	debug_printf ("SetTokenInformation(thread, "
 		      "TokenPrimaryGroup): %E");
       RevertToSelf ();
     }
@@ -2198,14 +2177,9 @@ setegid (__gid16_t gid)
       CloseHandle (ptok);
     }
   if (cygheap->user.token != INVALID_HANDLE_VALUE
-		      && cygheap->user.impersonated)
+      && cygheap->user.impersonated
-		    ImpersonateLoggedOnUser (cygheap->user.token);
+      && !ImpersonateLoggedOnUser (cygheap->user.token))
-		}
+    system_printf ("Impersonating in setegid failed: %E");
-	    }
-	}
-    }
-  else
-    set_errno (ENOSYS);
   return 0;
 }