cosmopolitan/test/libc/calls/pledge_test.c
Justine Tunney 48b2afb192
Address weakness with new pledge("anet") promise
The intent with pledge("anet") has been to prevent outbound connections.
However we were only doing that for TCP sockets, and outbound UDP could
still get through, by using socket() plus sendto(). This change fixed
that by preventing UDP sockets from being created.

Credit goes to chc4 on Hacker News for finding this.
2023-06-18 18:06:47 -07:00

681 lines
22 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/internal.h"
#include "libc/calls/ioctl.h"
#include "libc/calls/pledge.internal.h"
#include "libc/calls/struct/bpf.internal.h"
#include "libc/calls/struct/filter.internal.h"
#include "libc/calls/struct/flock.h"
#include "libc/calls/struct/seccomp.internal.h"
#include "libc/calls/struct/sigaction.h"
#include "libc/calls/struct/sigset.h"
#include "libc/calls/struct/stat.h"
#include "libc/calls/syscall_support-sysv.internal.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/intrin/kprintf.h"
#include "libc/macros.internal.h"
#include "libc/mem/mem.h"
#include "libc/runtime/internal.h"
#include "libc/runtime/runtime.h"
#include "libc/sock/sock.h"
#include "libc/sock/struct/sockaddr.h"
#include "libc/sock/struct/sockaddr6.h"
#include "libc/stdio/lock.internal.h"
#include "libc/stdio/stdio.h"
#include "libc/sysv/consts/af.h"
#include "libc/sysv/consts/at.h"
#include "libc/sysv/consts/f.h"
#include "libc/sysv/consts/fio.h"
#include "libc/sysv/consts/ipproto.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/nrlinux.h"
#include "libc/sysv/consts/o.h"
#include "libc/sysv/consts/pr.h"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/consts/sig.h"
#include "libc/sysv/consts/so.h"
#include "libc/sysv/consts/sock.h"
#include "libc/sysv/consts/sol.h"
#include "libc/testlib/ezbench.h"
#include "libc/testlib/subprocess.h"
#include "libc/testlib/testlib.h"
#include "libc/thread/spawn.h"
#include "libc/thread/thread.h"
#include "libc/time/time.h"
#include "libc/x/x.h"
char testlib_enable_tmp_setup_teardown;
void OnSig(int sig) {
// do nothing
}
int sys_memfd_secret(unsigned int); // our ENOSYS threshold
void SetUp(void) {
__enable_threads();
if (pledge(0, 0) == -1) {
fprintf(stderr, "warning: pledge() not supported on this system\n");
exit(0);
}
testlib_extract("/zip/life.elf", "life.elf", 0755);
testlib_extract("/zip/sock.elf", "sock.elf", 0755);
__pledge_mode = PLEDGE_PENALTY_RETURN_EPERM;
}
TEST(pledge, default_allowsExit) {
int *job;
int ws, pid;
// create small shared memory region
ASSERT_NE(-1, (job = mmap(0, FRAMESIZE, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, -1, 0)));
job[0] = 2; // create workload
job[1] = 2;
ASSERT_NE(-1, (pid = fork())); // create enclaved worker
if (!pid) {
ASSERT_SYS(0, 0, pledge("", 0));
job[0] = job[0] + job[1]; // do work
_Exit(0);
}
EXPECT_NE(-1, wait(&ws)); // wait for worker
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
EXPECT_EQ(4, job[0]); // check result
EXPECT_SYS(0, 0, munmap(job, FRAMESIZE));
}
TEST(pledge, execpromises_notok) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
__pledge_mode = PLEDGE_PENALTY_RETURN_EPERM;
ASSERT_SYS(0, 0, pledge("stdio rpath exec", "stdio"));
execl("sock.elf", "sock.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(129, WEXITSTATUS(ws));
}
int Enclave(void *arg, int tid) {
ASSERT_SYS(0, 0, pledge("", 0));
int *job = arg; // get job
job[0] = job[0] + job[1]; // do work
return 0; // exit
}
TEST(pledge, withThreadMemory) {
if (IsOpenbsd()) return; // openbsd doesn't allow it, wisely
struct spawn worker;
int job[2] = {2, 2}; // create workload
ASSERT_SYS(0, 0, _spawn(Enclave, job, &worker)); // create worker
ASSERT_SYS(0, 0, _join(&worker)); // wait for exit
EXPECT_EQ(4, job[0]); // check result
}
bool gotusr1;
void OnUsr1(int sig) {
gotusr1 = true;
}
int TgkillWorker(void *arg, int tid) {
sigset_t mask;
signal(SIGUSR1, OnUsr1);
sigemptyset(&mask);
ASSERT_SYS(EINTR, -1, sigsuspend(&mask));
ASSERT_TRUE(gotusr1);
return 0;
}
TEST(pledge, tgkill) {
// https://github.com/jart/cosmopolitan/issues/628
if (!IsLinux()) return;
sigset_t mask;
struct spawn worker;
SPAWN(fork);
sigemptyset(&mask);
sigaddset(&mask, SIGUSR1);
sigprocmask(SIG_BLOCK, &mask, 0);
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(0, 0, _spawn(TgkillWorker, 0, &worker));
ASSERT_SYS(0, 0, tgkill(getpid(), worker.ptid, SIGUSR1));
ASSERT_SYS(0, 0, _join(&worker));
EXITS(0);
}
TEST(pledge, stdio_forbidsOpeningPasswd1) {
if (!IsLinux()) return;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(EPERM, -1, open("/etc/passwd", O_RDWR));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
TEST(pledge, stdio_forbidsOpeningPasswd2) {
int ws, pid;
__pledge_mode = PLEDGE_PENALTY_KILL_PROCESS;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(EPERM, -1, open("/etc/passwd", O_RDWR));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFSIGNALED(ws));
EXPECT_EQ(IsOpenbsd() ? SIGABRT : SIGSYS, WTERMSIG(ws));
}
TEST(pledge, multipleCalls_canOnlyBecomeMoreRestrictive1) {
if (IsOpenbsd()) return;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(0, 0, pledge("stdio unix", 0));
ASSERT_SYS(0, 3, dup(2));
ASSERT_SYS(EPERM, -1, socket(AF_UNIX, SOCK_STREAM, 0));
ASSERT_SYS(0, 2, prctl(PR_GET_SECCOMP, 0, 0));
ASSERT_SYS(0, 0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
ASSERT_SYS(EINVAL, -1, prctl(PR_SET_NO_NEW_PRIVS, 0, 0, 0, 0));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
TEST(pledge, multipleCalls_canOnlyBecomeMoreRestrictive2) {
if (!IsOpenbsd()) return;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio", "stdio"));
ASSERT_SYS(EPERM, -1, pledge("stdio unix", "stdio unix"));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
TEST(pledge, multipleCalls_canOnlyBecomeMoreRestrictive3) {
if (!IsOpenbsd()) return;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio unix", 0));
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(0, 3, dup(2));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
TEST(pledge, stdio_fcntl_allowsSomeFirstArgs) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
struct flock lk;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio inet", 0));
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_NE(-1, fcntl(0, F_GETFL));
ASSERT_SYS(0, 0, fcntl(0, F_GETFD));
ASSERT_SYS(0, 3, fcntl(2, F_DUPFD_CLOEXEC, 3));
ASSERT_SYS(0, 0, ioctl(0, FIOCLEX, 0));
ASSERT_SYS(EPERM, 0, isatty(0));
ASSERT_SYS(EPERM, -1, fcntl(0, 777));
ASSERT_SYS(EPERM, -1, fcntl(0, F_GETLK, &lk));
ASSERT_SYS(EPERM, -1, fcntl(0, F_NOTIFY));
ASSERT_SYS(EPERM, -1, socket(AF_INET, SOCK_STREAM, IPPROTO_TCP));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, stdioTty_sendtoRestricted_requiresNullAddr) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid, sv[2];
ASSERT_SYS(0, 0, socketpair(AF_UNIX, SOCK_STREAM, 0, sv));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio tty", 0));
ASSERT_SYS(0, 5, send(sv[0], "hello", 5, 0));
ASSERT_SYS(0, 5, sendto(sv[0], "hello", 5, 0, 0, 0));
isatty(0);
ASSERT_NE(EPERM, errno);
errno = 0;
// set lower 32-bit word of pointer to zero lool
struct sockaddr_in *sin =
mmap((void *)0x300000000000, FRAMESIZE, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
sin->sin_family = AF_INET;
ASSERT_SYS(
EPERM, -1,
sendto(sv[0], "hello", 5, 0, (struct sockaddr *)sin, sizeof(*sin)));
_Exit(0);
}
close(sv[0]);
close(sv[1]);
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, unix_forbidsInetSockets) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio unix", 0));
ASSERT_SYS(0, 3, socket(AF_UNIX, SOCK_STREAM, 0));
ASSERT_SYS(0, 4, socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0));
ASSERT_SYS(EPERM, -1, socket(AF_INET, SOCK_STREAM, IPPROTO_TCP));
ASSERT_SYS(EPERM, -1, socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP));
ASSERT_SYS(EPERM, -1, socket(AF_UNIX, SOCK_RAW, 0));
ASSERT_SYS(EPERM, -1, socket(AF_UNIX, SOCK_STREAM, 1));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, wpath_doesNotImplyRpath) {
int ws, pid;
bool *gotsome;
ASSERT_NE(-1, (gotsome = _mapshared(FRAMESIZE)));
ASSERT_SYS(0, 0, touch("foo", 0644));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio wpath", 0));
ASSERT_SYS(0, 3, open("foo", O_WRONLY));
*gotsome = true;
ASSERT_SYS(EPERM, -1, open("foo", O_RDONLY));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
ASSERT_TRUE(*gotsome);
if (IsOpenbsd()) {
ASSERT_TRUE(WIFSIGNALED(ws));
ASSERT_EQ(SIGABRT, WTERMSIG(ws));
} else {
ASSERT_TRUE(WIFEXITED(ws));
ASSERT_EQ(0, WEXITSTATUS(ws));
}
}
TEST(pledge, inet_forbidsOtherSockets) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid, yes = 1;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio inet", 0));
ASSERT_SYS(0, 3, socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP));
ASSERT_SYS(0, 4, socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP));
ASSERT_SYS(0, 5, socket(AF_INET, SOCK_STREAM, IPPROTO_TCP));
ASSERT_SYS(0, 6, socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP));
ASSERT_SYS(0, 7, socket(AF_INET6, SOCK_DGRAM | SOCK_NONBLOCK, IPPROTO_UDP));
ASSERT_SYS(0, 0, setsockopt(3, SOL_SOCKET, SO_BROADCAST, &yes, 4));
ASSERT_SYS(EPERM, -1, socket(AF_UNIX, SOCK_STREAM, 0));
ASSERT_SYS(EPERM, -1, socket(AF_BLUETOOTH, SOCK_DGRAM, IPPROTO_UDP));
ASSERT_SYS(EPERM, -1, socket(AF_INET, SOCK_RAW, IPPROTO_UDP));
ASSERT_SYS(EPERM, -1, socket(AF_INET, SOCK_DGRAM, IPPROTO_RAW));
ASSERT_SYS(EPERM, -1, setsockopt(3, SOL_SOCKET, SO_TIMESTAMP, &yes, 4));
struct sockaddr_in sin = {AF_INET, 0, {htonl(0x7f000001)}};
ASSERT_SYS(0, 0, bind(4, (struct sockaddr *)&sin, sizeof(sin)));
struct sockaddr_in6 sin6 = {.sin6_family = AF_INET6,
.sin6_addr.s6_addr[15] = 1};
ASSERT_SYS(0, 0, bind(6, (struct sockaddr *)&sin6, sizeof(sin6)));
uint32_t az = sizeof(sin);
ASSERT_SYS(0, 0, getsockname(4, (struct sockaddr *)&sin, &az));
ASSERT_SYS(0, 5,
sendto(3, "hello", 5, 0, (struct sockaddr *)&sin, sizeof(sin)));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, anet_forbidsUdpSocketsAndConnect) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid, yes = 1;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio anet", 0));
ASSERT_SYS(0, 3, socket(AF_INET, SOCK_STREAM, IPPROTO_TCP));
ASSERT_SYS(EPERM, -1, socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP));
ASSERT_SYS(EPERM, -1, setsockopt(3, SOL_SOCKET, SO_TIMESTAMP, &yes, 4));
struct sockaddr_in sin = {AF_INET, 0, {htonl(0x7f000001)}};
ASSERT_SYS(EPERM, -1, connect(4, (struct sockaddr *)&sin, sizeof(sin)));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_EQ(0, ws);
}
TEST(pledge, mmap) {
if (IsOpenbsd()) return; // b/c testing linux bpf
char *p;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_NE(MAP_FAILED, (p = mmap(0, FRAMESIZE, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0)));
ASSERT_SYS(0, 0, mprotect(p, FRAMESIZE, PROT_READ));
ASSERT_SYS(EPERM, MAP_FAILED,
mprotect(p, FRAMESIZE, PROT_READ | PROT_EXEC));
ASSERT_SYS(EPERM, MAP_FAILED,
mmap(0, FRAMESIZE, PROT_EXEC | PROT_READ,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, mmapProtExec) {
if (IsOpenbsd()) return; // b/c testing linux bpf
char *p;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio prot_exec", 0));
ASSERT_NE(MAP_FAILED, (p = mmap(0, FRAMESIZE, PROT_READ | PROT_WRITE,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0)));
ASSERT_SYS(0, 0, mprotect(p, FRAMESIZE, PROT_READ));
ASSERT_SYS(0, 0, mprotect(p, FRAMESIZE, PROT_READ | PROT_EXEC));
ASSERT_NE(MAP_FAILED, mmap(0, FRAMESIZE, PROT_EXEC | PROT_READ,
MAP_ANONYMOUS | MAP_PRIVATE, -1, 0));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, chmod_ignoresDangerBits) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_SYS(0, 3, creat("foo", 0644));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio rpath wpath", 0));
ASSERT_SYS(0, 0, fchmod(3, 00700));
ASSERT_SYS(0, 0, chmod("foo", 00700));
ASSERT_SYS(0, 0, fchmodat(AT_FDCWD, "foo", 00700, 0));
ASSERT_SYS(EPERM, -1, fchmod(3, 07700));
ASSERT_SYS(EPERM, -1, chmod("foo", 04700));
ASSERT_SYS(EPERM, -1, fchmodat(AT_FDCWD, "foo", 02700, 0));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
close(3);
}
TEST(pledge, open_rpath) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_SYS(0, 0, touch("foo", 0644));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio rpath", 0));
ASSERT_SYS(0, 3, open("foo", O_RDONLY));
ASSERT_SYS(EPERM, -1, open("foo", O_RDONLY | O_TRUNC));
ASSERT_SYS(EPERM, -1, open("foo", O_RDONLY | O_TMPFILE));
ASSERT_SYS(EPERM, -1, open("foo", O_RDWR | O_TRUNC | O_CREAT, 0644));
ASSERT_SYS(EPERM, -1, open("foo", O_WRONLY | O_TRUNC | O_CREAT, 0644));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, open_wpath) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_SYS(0, 0, touch("foo", 0644));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio wpath", 0));
ASSERT_SYS(EPERM, -1, open(".", O_RDWR | O_TMPFILE, 07644));
ASSERT_SYS(0, 3, open("foo", O_WRONLY | O_TRUNC));
ASSERT_SYS(0, 4, open("foo", O_RDWR));
ASSERT_SYS(EPERM, -1, open("foo", O_WRONLY | O_TRUNC | O_CREAT, 0644));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, open_cpath) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
struct stat st;
ASSERT_SYS(0, 0, touch("foo", 0644));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio cpath", 0));
ASSERT_SYS(0, 3, open("foo", O_WRONLY | O_TRUNC | O_CREAT, 0644));
ASSERT_SYS(0, 0, fstat(3, &st));
ASSERT_EQ(0100644, st.st_mode);
// make sure open() can't apply the setuid bit
ASSERT_SYS(EPERM, -1, open("bar", O_WRONLY | O_TRUNC | O_CREAT, 04644));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws) && !WEXITSTATUS(ws));
}
TEST(pledge, execpromises_ok) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio exec", "stdio"));
execl("life.elf", "life.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(42, WEXITSTATUS(ws));
}
TEST(pledge, execpromises_notok1) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio exec", "stdio"));
execl("sock.elf", "sock.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(128 + EPERM, WEXITSTATUS(ws));
}
TEST(pledge, execpromises_reducesAtExecOnLinux) {
if (IsOpenbsd()) return; // b/c testing linux bpf
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio inet tty exec", "stdio tty"));
execl("sock.elf", "sock.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(128 + EPERM, WEXITSTATUS(ws));
}
TEST(pledge_openbsd, execpromisesIsNull_letsItDoAnything) {
if (!IsOpenbsd()) return;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio exec", 0));
execl("sock.elf", "sock.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(3, WEXITSTATUS(ws));
}
TEST(pledge_openbsd, execpromisesIsSuperset_letsItDoAnything) {
if (!IsOpenbsd()) return;
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio rpath exec", "stdio rpath tty inet"));
execl("sock.elf", "sock.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(3, WEXITSTATUS(ws));
}
TEST(pledge_linux, execpromisesIsSuperset_notPossible) {
if (IsOpenbsd()) return;
ASSERT_SYS(EINVAL, -1, pledge("stdio exec", "stdio inet exec"));
}
TEST(pledge_openbsd, execpromises_notok) {
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio exec", "stdio"));
execl("sock.elf", "sock.elf", 0);
_Exit(127);
}
EXPECT_NE(-1, wait(&ws));
if (IsOpenbsd()) {
EXPECT_TRUE(WIFSIGNALED(ws));
EXPECT_EQ(SIGABRT, WTERMSIG(ws));
} else {
// linux can't be consistent here since we pledged exec
// so we return EPERM instead and sock.elf passes along
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(128 + EPERM, WEXITSTATUS(ws));
}
}
TEST(pledge_openbsd, bigSyscalls) {
if (IsOpenbsd()) return; // testing lunix
int ws, pid;
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(ENOSYS, -1, sys_memfd_secret(0));
ASSERT_SYS(ENOSYS, -1, sys_bogus());
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
int LockWorker(void *arg, int tid) {
flockfile(stdout);
ASSERT_EQ(gettid(), ((pthread_mutex_t *)stdout->lock)->_owner);
funlockfile(stdout);
return 0;
}
TEST(pledge, threadWithLocks_canCodeMorph) {
struct spawn worker;
int ws, pid;
// not sure how this works on OpenBSD but it works!
if (!fork()) {
__enable_threads();
ASSERT_SYS(0, 0, pledge("stdio", 0));
ASSERT_SYS(0, 0, _spawn(LockWorker, 0, &worker));
ASSERT_SYS(0, 0, _join(&worker));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
TEST(pledge, everything) {
int ws, pid;
if (!fork()) {
// contains 591 bpf instructions [2022-07-24]
ASSERT_SYS(0, 0,
pledge("stdio rpath wpath cpath dpath "
"flock fattr inet unix dns tty "
"recvfd sendfd proc exec id "
"unveil settime prot_exec "
"vminfo tmppath",
"stdio rpath wpath cpath dpath "
"flock fattr inet unix dns tty "
"recvfd sendfd proc exec id "
"unveil settime prot_exec "
"vminfo tmppath"));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
TEST(pledge, execWithoutRpath) {
int ws, pid;
ASSERT_SYS(0, 0, touch("foo", 0644));
ASSERT_NE(-1, (pid = fork()));
if (!pid) {
ASSERT_SYS(0, 0, pledge("stdio prot_exec exec", "stdio prot_exec exec"));
ASSERT_SYS(EPERM, -1, open("foo", O_RDONLY));
_Exit(0);
}
EXPECT_NE(-1, wait(&ws));
if (IsOpenbsd()) {
EXPECT_TRUE(WIFSIGNALED(ws));
EXPECT_EQ(SIGABRT, WTERMSIG(ws));
} else {
EXPECT_TRUE(WIFEXITED(ws));
EXPECT_EQ(0, WEXITSTATUS(ws));
}
}
BENCH(pledge, bench) {
int pid;
if (!fork()) {
ASSERT_SYS(0, 0, pledge("stdio", 0));
EZBENCH2("sched_yield", donothing, sched_yield());
_Exit(0);
}
wait(0);
}