mirror of
https://github.com/samba-team/samba.git
synced 2024-12-24 21:34:56 +03:00
dde0705807
deferred reply is short-circuited immediately when the file is
closed by another user, allowing it to be opened by the waiting user.
- added a sane set of timeval manipulation routines
- converted all the events code and code that uses it to use struct
timeval instead of time_t, which allows for microsecond resolution
instead of 1 second resolution. This was needed for doing the pvfs
deferred open code, and is why the patch is so big.
(This used to be commit 0d51511d40)
70 lines
2.0 KiB
C
70 lines
2.0 KiB
C
/*
|
|
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/passwd.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 too 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_p(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;
|
|
}
|
|
|