mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-02-01 03:53:33 +00:00
6b3d257588
We're now able to drop both `exec` and `prot_exec` privileges automatically when launching glibc dynamic executables. We also have really outstanding standard error logging now, that explains which promises are needed, even in cases where `exec` is used.
50 lines
2.5 KiB
C
50 lines
2.5 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Copyright 2022 Justine Alexandra Roberts Tunney │
|
|
│ │
|
|
│ Permission to use, copy, modify, and/or distribute this software for │
|
|
│ any purpose with or without fee is hereby granted, provided that the │
|
|
│ above copyright notice and this permission notice appear in all copies. │
|
|
│ │
|
|
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
|
|
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
|
|
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
|
|
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
|
|
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
|
|
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
|
|
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
|
|
│ PERFORMANCE OF THIS SOFTWARE. │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/calls/pledge.h"
|
|
#include "libc/calls/pledge.internal.h"
|
|
#include "libc/intrin/promises.internal.h"
|
|
#include "libc/runtime/runtime.h"
|
|
|
|
/*
|
|
* runs pledge at glibc executable load time, e.g.
|
|
* strace -vff bash -c '_PLEDGE=4194303,0,1 LD_PRELOAD=$HOME/sandbox.so ls'
|
|
*/
|
|
|
|
hidden uint8_t __privileged_start[1];
|
|
hidden uint8_t __privileged_end[1];
|
|
|
|
__attribute__((__constructor__)) void init(void) {
|
|
int c, i, j;
|
|
const char *s;
|
|
uint64_t arg[3] = {0};
|
|
s = getenv("_PLEDGE");
|
|
for (i = j = 0; i < 3; ++i) {
|
|
while ((c = s[j] & 255)) {
|
|
++j;
|
|
if ('0' <= c & c <= '9') {
|
|
arg[i] *= 10;
|
|
arg[i] += c - '0';
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
sys_pledge_linux(~arg[0], arg[1], arg[2]);
|
|
}
|