diff options
author | Jelmer Vernooij <jelmer@samba.org> | 2006-02-23 15:52:24 +0000 |
---|---|---|
committer | Gerald (Jerry) Carter <jerry@samba.org> | 2007-10-10 13:52:05 -0500 |
commit | dfc517b05395d925a4d7b1ce9633a849f9468e70 (patch) | |
tree | a81c020c89022980e6fbb68116648da217fbb0fc /source4/lib/util/unix_privs.c | |
parent | 80c8a522861068e7b0974986936f65052dd6f70f (diff) | |
download | samba-dfc517b05395d925a4d7b1ce9633a849f9468e70.tar.gz samba-dfc517b05395d925a4d7b1ce9633a849f9468e70.tar.bz2 samba-dfc517b05395d925a4d7b1ce9633a849f9468e70.zip |
r13658: More moving around of files:
- Collect the generic utility functions into a lib/util/ (a la GLib is
for the GNOME folks)
- Remove even more files from include/
(This used to be commit ba62880f5b05c2a505dc7f54676b231197a7e707)
Diffstat (limited to 'source4/lib/util/unix_privs.c')
-rw-r--r-- | source4/lib/util/unix_privs.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/source4/lib/util/unix_privs.c b/source4/lib/util/unix_privs.c new file mode 100644 index 0000000000..3c0f319776 --- /dev/null +++ b/source4/lib/util/unix_privs.c @@ -0,0 +1,68 @@ +/* + Unix SMB/CIFS implementation. + + gain/lose root privileges + + Copyright (C) Andrew Tridgell 2004 + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +#include "includes.h" +#include "system/filesys.h" + +/* + there are times when smbd needs to temporarily gain root privileges + to do some operation. To do this you call root_privileges(), which + returns a talloc handle. To restore your previous privileges + talloc_free() this pointer. + + Note that this call is considered successful even if it does not + manage to gain root privileges, but it will call smb_abort() if it + fails to restore the privileges afterwards. The logic is that + failing to gain root access can be caught by whatever operation + needs to be run as root failing, but failing to lose the root + privileges is dangerous. + + This also means that this code is safe to be called from completely + unprivileged processes. +*/ + +struct saved_state { + uid_t uid; +}; + +static int privileges_destructor(void *ptr) +{ + struct saved_state *s = ptr; + if (geteuid() != s->uid && + seteuid(s->uid) != 0) { + smb_panic("Failed to restore privileges"); + } + return 0; +} + +void *root_privileges(void) +{ + struct saved_state *s; + s = talloc(NULL, struct saved_state); + if (!s) return NULL; + s->uid = geteuid(); + if (s->uid != 0) { + seteuid(0); + } + talloc_set_destructor(s, privileges_destructor); + return s; +} |