mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 11:37:35 +00:00
258 lines
8.3 KiB
C
258 lines
8.3 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│ vi: set et 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/assert.h"
|
|
#include "libc/calls/blockcancel.internal.h"
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/calls/cp.internal.h"
|
|
#include "libc/calls/internal.h"
|
|
#include "libc/calls/struct/sigset.internal.h"
|
|
#include "libc/calls/struct/stat.internal.h"
|
|
#include "libc/calls/syscall-sysv.internal.h"
|
|
#include "libc/dce.h"
|
|
#include "libc/errno.h"
|
|
#include "libc/fmt/itoa.h"
|
|
#include "libc/intrin/describeflags.h"
|
|
#include "libc/intrin/kprintf.h"
|
|
#include "libc/intrin/safemacros.h"
|
|
#include "libc/intrin/strace.h"
|
|
#include "libc/intrin/weaken.h"
|
|
#include "libc/limits.h"
|
|
#include "libc/proc/execve.internal.h"
|
|
#include "libc/str/str.h"
|
|
#include "libc/sysv/consts/f.h"
|
|
#include "libc/sysv/consts/fd.h"
|
|
#include "libc/sysv/consts/map.h"
|
|
#include "libc/sysv/consts/mfd.h"
|
|
#include "libc/sysv/consts/o.h"
|
|
#include "libc/sysv/consts/prot.h"
|
|
#include "libc/sysv/consts/shm.h"
|
|
#include "libc/sysv/errfuns.h"
|
|
|
|
static bool IsAPEFd(const int fd) {
|
|
char buf[8];
|
|
return (sys_pread(fd, buf, 8, 0, 0) == 8) && IsApeLoadable(buf);
|
|
}
|
|
|
|
static int fexecve_impl(const int fd, char *const argv[], char *const envp[]) {
|
|
int rc;
|
|
if (IsLinux()) {
|
|
char path[14 + 12];
|
|
FormatInt32(stpcpy(path, "/proc/self/fd/"), fd);
|
|
rc = __sys_execve(path, argv, envp);
|
|
} else if (IsFreebsd()) {
|
|
rc = sys_fexecve(fd, argv, envp);
|
|
} else {
|
|
rc = enosys();
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
typedef enum {
|
|
PTF_NUM = 1 << 0,
|
|
PTF_NUM2 = 1 << 1,
|
|
PTF_NUM3 = 1 << 2,
|
|
PTF_ANY = 1 << 3
|
|
} PTF_PARSE;
|
|
|
|
static bool ape_to_elf(void *ape, const size_t apesize) {
|
|
static const char printftok[] = "printf '";
|
|
static const size_t printftoklen = sizeof(printftok) - 1;
|
|
const char *tok = memmem(ape, apesize, printftok, printftoklen);
|
|
if (tok) {
|
|
tok += printftoklen;
|
|
uint8_t *dest = ape;
|
|
PTF_PARSE state = PTF_ANY;
|
|
uint8_t value = 0;
|
|
for (; tok < (const char *)(dest + apesize); tok++) {
|
|
if ((state & (PTF_NUM | PTF_NUM2 | PTF_NUM3)) &&
|
|
(*tok >= '0' && *tok <= '7')) {
|
|
value = (value << 3) | (*tok - '0');
|
|
state <<= 1;
|
|
if (state & PTF_ANY) {
|
|
*dest++ = value;
|
|
}
|
|
} else if (state & PTF_NUM) {
|
|
break;
|
|
} else {
|
|
if (state & (PTF_NUM2 | PTF_NUM3)) {
|
|
*dest++ = value;
|
|
}
|
|
if (*tok == '\\') {
|
|
state = PTF_NUM;
|
|
value = 0;
|
|
} else if (*tok == '\'') {
|
|
return true;
|
|
} else {
|
|
*dest++ = *tok;
|
|
state = PTF_ANY;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
errno = ENOEXEC;
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Creates a memfd and copies fd to it.
|
|
*
|
|
* This does an inplace conversion of APE to ELF when detected!!!!
|
|
*/
|
|
static int fd_to_mem_fd(const int infd, char *path) {
|
|
if ((!IsLinux() && !IsFreebsd()) || !_weaken(mmap) || !_weaken(munmap)) {
|
|
return enosys();
|
|
}
|
|
|
|
struct stat st;
|
|
if (fstat(infd, &st) == -1) {
|
|
return -1;
|
|
}
|
|
int fd;
|
|
if (IsLinux()) {
|
|
fd = sys_memfd_create(__func__, MFD_CLOEXEC);
|
|
} else if (IsFreebsd()) {
|
|
fd = sys_shm_open(SHM_ANON, O_CREAT | O_RDWR, 0);
|
|
} else {
|
|
return enosys();
|
|
}
|
|
if (fd == -1) {
|
|
return -1;
|
|
}
|
|
void *space;
|
|
if ((sys_ftruncate(fd, st.st_size, st.st_size) != -1) &&
|
|
((space = _weaken(mmap)(0, st.st_size, PROT_READ | PROT_WRITE, MAP_SHARED,
|
|
fd, 0)) != MAP_FAILED)) {
|
|
ssize_t readRc;
|
|
readRc = pread(infd, space, st.st_size, 0);
|
|
bool success = readRc != -1;
|
|
if (success && (st.st_size > 8) && IsApeLoadable(space)) {
|
|
int flags = fcntl(fd, F_GETFD);
|
|
if ((success = (flags != -1) &&
|
|
(fcntl(fd, F_SETFD, flags & (~FD_CLOEXEC)) != -1) &&
|
|
ape_to_elf(space, st.st_size))) {
|
|
const int newfd = fcntl(fd, F_DUPFD, 9001);
|
|
if (newfd != -1) {
|
|
close(fd);
|
|
fd = newfd;
|
|
}
|
|
}
|
|
}
|
|
const int e = errno;
|
|
if ((_weaken(munmap)(space, st.st_size) != -1) && success) {
|
|
if (path) {
|
|
FormatInt32(stpcpy(path, "COSMOPOLITAN_INIT_ZIPOS="), fd);
|
|
}
|
|
unassert(readRc == st.st_size);
|
|
return fd;
|
|
} else if (!success) {
|
|
errno = e;
|
|
}
|
|
}
|
|
const int e = errno;
|
|
close(fd);
|
|
errno = e;
|
|
return -1;
|
|
}
|
|
|
|
/**
|
|
* Executes binary executable at file descriptor.
|
|
*
|
|
* This is only supported on Linux and FreeBSD. APE binaries are
|
|
* supported. Zipos is supported. Zipos fds or FD_CLOEXEC APE fds or
|
|
* fds that fail fexecve with ENOEXEC are copied to a new memfd (with
|
|
* in-memory APE to ELF conversion) and fexecve is (re)attempted.
|
|
*
|
|
* @param fd is opened executable and current file position is ignored
|
|
* @return doesn't return on success, otherwise -1 w/ errno
|
|
* @raise ENOEXEC if file at `fd` isn't an assimilated ELF executable
|
|
* @raise ENOSYS on Windows, XNU, OpenBSD, NetBSD, and Metal
|
|
*/
|
|
int fexecve(int fd, char *const argv[], char *const envp[]) {
|
|
int rc = 0;
|
|
if (!argv || !envp) {
|
|
rc = efault();
|
|
} else {
|
|
STRACE("fexecve(%d, %s, %s) → ...", fd, DescribeStringList(argv),
|
|
DescribeStringList(envp));
|
|
int savedErr = 0;
|
|
do {
|
|
if (!IsLinux() && !IsFreebsd()) {
|
|
rc = enosys();
|
|
break;
|
|
}
|
|
if (!__isfdkind(fd, kFdZip)) {
|
|
bool memfdReq;
|
|
BLOCK_SIGNALS;
|
|
BLOCK_CANCELATION;
|
|
strace_enabled(-1);
|
|
memfdReq = ((rc = fcntl(fd, F_GETFD)) != -1) && (rc & FD_CLOEXEC) &&
|
|
IsAPEFd(fd);
|
|
strace_enabled(+1);
|
|
ALLOW_CANCELATION;
|
|
ALLOW_SIGNALS;
|
|
if (rc == -1) {
|
|
break;
|
|
} else if (!memfdReq) {
|
|
fexecve_impl(fd, argv, envp);
|
|
if (errno != ENOEXEC) {
|
|
break;
|
|
}
|
|
savedErr = ENOEXEC;
|
|
}
|
|
}
|
|
int newfd;
|
|
char *path = alloca(PATH_MAX);
|
|
BLOCK_SIGNALS;
|
|
BLOCK_CANCELATION;
|
|
strace_enabled(-1);
|
|
newfd = fd_to_mem_fd(fd, path);
|
|
strace_enabled(+1);
|
|
ALLOW_CANCELATION;
|
|
ALLOW_SIGNALS;
|
|
if (newfd == -1) {
|
|
break;
|
|
}
|
|
size_t numenvs;
|
|
for (numenvs = 0; envp[numenvs];)
|
|
++numenvs;
|
|
// const size_t desenvs = min(500, max(numenvs + 1, 2));
|
|
static _Thread_local char *envs[500];
|
|
memcpy(envs, envp, numenvs * sizeof(char *));
|
|
envs[numenvs] = path;
|
|
envs[numenvs + 1] = NULL;
|
|
fexecve_impl(newfd, argv, envs);
|
|
if (!savedErr) {
|
|
savedErr = errno;
|
|
}
|
|
BLOCK_SIGNALS;
|
|
BLOCK_CANCELATION;
|
|
strace_enabled(-1);
|
|
close(newfd);
|
|
strace_enabled(+1);
|
|
ALLOW_CANCELATION;
|
|
ALLOW_SIGNALS;
|
|
} while (0);
|
|
if (savedErr) {
|
|
errno = savedErr;
|
|
}
|
|
rc = -1;
|
|
}
|
|
STRACE("fexecve(%d) failed %d% m", fd, rc);
|
|
return rc;
|
|
}
|