mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-03-02 15:08:41 +00:00
f4f4caab0e
I wanted a tiny scriptable meltdown proof way to run userspace programs and visualize how program execution impacts memory. It helps to explain how things like Actually Portable Executable works. It can show you how the GCC generated code is going about manipulating matrices and more. I didn't feel fully comfortable with Qemu and Bochs because I'm not smart enough to understand them. I wanted something like gVisor but with much stronger levels of assurances. I wanted a single binary that'll run, on all major operating systems with an embedded GPL barrier ZIP filesystem that is tiny enough to transpile to JavaScript and run in browsers too. https://justine.storage.googleapis.com/emulator625.mp4
315 lines
12 KiB
C
315 lines
12 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 2020 Justine Alexandra Roberts Tunney │
|
|
│ │
|
|
│ 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; version 2 of the License. │
|
|
│ │
|
|
│ 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., 51 Franklin Street, Fifth Floor, Boston, MA │
|
|
│ 02110-1301 USA │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/alg/arraylist.h"
|
|
#include "libc/bits/bits.h"
|
|
#include "libc/bits/safemacros.h"
|
|
#include "libc/calls/calls.h"
|
|
#include "libc/calls/struct/stat.h"
|
|
#include "libc/calls/struct/timespec.h"
|
|
#include "libc/dos.h"
|
|
#include "libc/elf/def.h"
|
|
#include "libc/limits.h"
|
|
#include "libc/log/check.h"
|
|
#include "libc/log/log.h"
|
|
#include "libc/macros.h"
|
|
#include "libc/mem/alloca.h"
|
|
#include "libc/nexgen32e/crc32.h"
|
|
#include "libc/nt/enum/fileflagandattributes.h"
|
|
#include "libc/nt/struct/imageauxsymbolex.h"
|
|
#include "libc/runtime/gc.h"
|
|
#include "libc/runtime/runtime.h"
|
|
#include "libc/runtime/symbols.h"
|
|
#include "libc/stdio/stdio.h"
|
|
#include "libc/str/str.h"
|
|
#include "libc/sysv/consts/ex.h"
|
|
#include "libc/sysv/consts/exit.h"
|
|
#include "libc/sysv/consts/fileno.h"
|
|
#include "libc/sysv/consts/map.h"
|
|
#include "libc/sysv/consts/o.h"
|
|
#include "libc/sysv/consts/ok.h"
|
|
#include "libc/sysv/consts/prot.h"
|
|
#include "libc/time/struct/tm.h"
|
|
#include "libc/time/time.h"
|
|
#include "libc/x/x.h"
|
|
#include "libc/zip.h"
|
|
#include "third_party/getopt/getopt.h"
|
|
#include "third_party/zlib/zlib.h"
|
|
#include "tool/build/lib/elfwriter.h"
|
|
|
|
#define ZIP_LOCALFILE_SECTION ".piro.data.sort.zip.2."
|
|
#define ZIP_DIRECTORY_SECTION ".piro.data.sort.zip.4."
|
|
|
|
#define PUT8(P, V) *P++ = V
|
|
#define PUT16(P, V) P[0] = V & 0xff, P[1] = V >> 010 & 0xff, P += 2
|
|
#define PUT32(P, V) \
|
|
P[0] = V & 0xff, P[1] = V >> 010 & 0xff, P[2] = V >> 020 & 0xff, \
|
|
P[3] = V >> 030 & 0xff, P += 4
|
|
|
|
char *symbol_;
|
|
char *outpath_;
|
|
char *yoink_;
|
|
|
|
const size_t kMinCompressSize = 32;
|
|
const char kNoCompressExts[][8] = {".gz", ".xz", ".jpg", ".png",
|
|
".gif", ".zip", ".bz2", ".mpg",
|
|
".mp4", ".lz4", ".webp", ".mpeg"};
|
|
|
|
noreturn void PrintUsage(int rc, FILE *f) {
|
|
fprintf(f, "%s%s%s\n", "Usage: ", program_invocation_name,
|
|
" [-o FILE] [-s SYMBOL] [-y YOINK] [FILE...]\n");
|
|
exit(rc);
|
|
}
|
|
|
|
void GetOpts(int *argc, char ***argv) {
|
|
int opt;
|
|
yoink_ = "__zip_start";
|
|
while ((opt = getopt(*argc, *argv, "?ho:s:y:")) != -1) {
|
|
switch (opt) {
|
|
case 'o':
|
|
outpath_ = optarg;
|
|
break;
|
|
case 's':
|
|
symbol_ = optarg;
|
|
break;
|
|
case 'y':
|
|
yoink_ = optarg;
|
|
break;
|
|
case '?':
|
|
case 'h':
|
|
PrintUsage(EXIT_SUCCESS, stdout);
|
|
default:
|
|
PrintUsage(EX_USAGE, stderr);
|
|
}
|
|
}
|
|
*argc -= optind;
|
|
*argv += optind;
|
|
CHECK_NOTNULL(outpath_);
|
|
}
|
|
|
|
bool IsPureAscii(const void *data, size_t size) {
|
|
const unsigned char *p, *pe;
|
|
for (p = data, pe = p + size; p < pe; ++p) {
|
|
if (!*p || *p >= 0x80) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool ShouldCompress(const char *name, size_t size) {
|
|
size_t i;
|
|
char key[8];
|
|
const char *p;
|
|
if (!(p = memrchr(name, '.', size))) return true;
|
|
strncpy(key, p, sizeof(key));
|
|
for (i = 0; i < ARRAYLEN(kNoCompressExts); ++i) {
|
|
if (memcmp(key, kNoCompressExts[i], sizeof(key)) == 0) return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void GetDosLocalTime(int64_t utcunixts, uint16_t *out_time,
|
|
uint16_t *out_date) {
|
|
struct tm tm;
|
|
CHECK_NOTNULL(localtime_r(&utcunixts, &tm));
|
|
*out_time = DOS_TIME(tm.tm_hour, tm.tm_min, tm.tm_sec);
|
|
*out_date = DOS_DATE(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday);
|
|
}
|
|
|
|
static unsigned char *EmitZipLfileHdr(unsigned char *op, const void *name,
|
|
size_t namesize, uint32_t crc,
|
|
uint8_t era, uint16_t gflags,
|
|
uint16_t method, uint16_t mtime,
|
|
uint16_t mdate, size_t compsize,
|
|
size_t uncompsize) {
|
|
PUT32(op, kZipLfileHdrMagic);
|
|
PUT8(op, era);
|
|
PUT8(op, kZipOsDos);
|
|
PUT16(op, gflags);
|
|
PUT16(op, method);
|
|
PUT16(op, mtime);
|
|
PUT16(op, mdate);
|
|
PUT32(op, crc);
|
|
PUT32(op, compsize);
|
|
PUT32(op, uncompsize);
|
|
PUT16(op, namesize);
|
|
PUT16(op, 0); /* extra */
|
|
return mempcpy(op, name, namesize);
|
|
}
|
|
|
|
static void EmitZipCdirHdr(unsigned char *op, const void *name, size_t namesize,
|
|
uint32_t crc, uint8_t era, uint16_t gflags,
|
|
uint16_t method, uint16_t mtime, uint16_t mdate,
|
|
uint16_t iattrs, uint16_t dosmode, uint16_t unixmode,
|
|
size_t compsize, size_t uncompsize,
|
|
size_t commentsize) {
|
|
PUT32(op, kZipCfileHdrMagic);
|
|
PUT8(op, kZipCosmopolitanVersion);
|
|
PUT8(op, kZipOsUnix);
|
|
PUT8(op, era);
|
|
PUT8(op, kZipOsDos);
|
|
PUT16(op, gflags);
|
|
PUT16(op, method);
|
|
PUT16(op, mtime);
|
|
PUT16(op, mdate);
|
|
PUT32(op, crc);
|
|
PUT32(op, compsize);
|
|
PUT32(op, uncompsize);
|
|
PUT16(op, namesize);
|
|
PUT16(op, 0); /* extra size */
|
|
PUT16(op, commentsize);
|
|
PUT16(op, 0); /* disk */
|
|
PUT16(op, iattrs);
|
|
PUT16(op, dosmode);
|
|
PUT16(op, unixmode);
|
|
PUT32(op, 0); /* RELOCATE ME (kZipCfileOffsetOffset) */
|
|
memcpy(op, name, namesize);
|
|
}
|
|
|
|
void EmitZip(struct ElfWriter *elf, const char *name, size_t namesize,
|
|
const unsigned char *data, struct stat *st) {
|
|
z_stream zs;
|
|
uint8_t era;
|
|
uint32_t crc;
|
|
unsigned char *lfile, *cfile;
|
|
struct ElfWriterSymRef lfilesym;
|
|
size_t lfilehdrsize, uncompsize, compsize, commentsize;
|
|
uint16_t method, gflags, mtime, mdate, iattrs, dosmode;
|
|
|
|
compsize = st->st_size;
|
|
uncompsize = st->st_size;
|
|
CHECK_LE(uncompsize, UINT32_MAX);
|
|
lfilehdrsize = kZipLfileHdrMinSize + namesize;
|
|
crc = crc32_z(0, data, uncompsize);
|
|
GetDosLocalTime(st->st_mtim.tv_sec, &mtime, &mdate);
|
|
gflags = IsPureAscii(name, namesize) ? 0 : kZipGflagUtf8;
|
|
commentsize = kZipCdirHdrLinkableSize - (kZipCfileHdrMinSize + namesize);
|
|
iattrs = IsPureAscii(data, st->st_size) ? kZipIattrAscii : kZipIattrBinary;
|
|
dosmode = !(st->st_mode & 0200) ? kNtFileAttributeReadonly : 0;
|
|
method = (st->st_size >= kMinCompressSize && ShouldCompress(name, namesize))
|
|
? kZipCompressionDeflate
|
|
: kZipCompressionNone;
|
|
|
|
/* emit embedded file content w/ pkzip local file header */
|
|
elfwriter_align(elf, kZipCdirAlign, 0);
|
|
elfwriter_startsection(elf,
|
|
gc(xasprintf("%s%s", ZIP_LOCALFILE_SECTION, name)),
|
|
SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
|
|
if (method == kZipCompressionDeflate) {
|
|
CHECK_EQ(Z_OK, deflateInit2(memset(&zs, 0, sizeof(zs)),
|
|
Z_DEFAULT_COMPRESSION, Z_DEFLATED, -MAX_WBITS,
|
|
MAX_MEM_LEVEL, Z_DEFAULT_STRATEGY));
|
|
zs.next_in = data;
|
|
zs.avail_in = uncompsize;
|
|
zs.next_out = ((lfile = elfwriter_reserve(
|
|
elf, (lfilehdrsize +
|
|
(zs.avail_out = compressBound(uncompsize))))) +
|
|
lfilehdrsize);
|
|
CHECK_EQ(Z_STREAM_END, deflate(&zs, Z_FINISH));
|
|
CHECK_EQ(Z_OK, deflateEnd(&zs));
|
|
if (zs.total_out < uncompsize) {
|
|
compsize = zs.total_out;
|
|
} else {
|
|
method = kZipCompressionNone;
|
|
}
|
|
} else {
|
|
lfile = elfwriter_reserve(elf, lfilehdrsize + uncompsize);
|
|
}
|
|
if (method == kZipCompressionNone) {
|
|
memcpy(lfile + lfilehdrsize, data, uncompsize);
|
|
}
|
|
era = (gflags || method) ? kZipEra1993 : kZipEra1989;
|
|
EmitZipLfileHdr(lfile, name, namesize, crc, era, gflags, method, mtime, mdate,
|
|
compsize, uncompsize);
|
|
elfwriter_commit(elf, lfilehdrsize + compsize);
|
|
lfilesym = elfwriter_appendsym(elf, gc(xasprintf("%s%s", "zip+lfile:", name)),
|
|
ELF64_ST_INFO(STB_LOCAL, STT_OBJECT),
|
|
STV_DEFAULT, 0, lfilehdrsize);
|
|
elfwriter_appendsym(elf, name, ELF64_ST_INFO(STB_GLOBAL, STT_OBJECT),
|
|
STV_DEFAULT, lfilehdrsize, compsize);
|
|
elfwriter_finishsection(elf);
|
|
|
|
/* emit central directory record */
|
|
elfwriter_align(elf, kZipCdirAlign, 0);
|
|
elfwriter_startsection(elf,
|
|
gc(xasprintf("%s%s", ZIP_DIRECTORY_SECTION, name)),
|
|
SHT_PROGBITS, SHF_ALLOC | SHF_WRITE);
|
|
EmitZipCdirHdr((cfile = elfwriter_reserve(elf, kZipCdirHdrLinkableSize)),
|
|
name, namesize, crc, era, gflags, method, mtime, mdate, iattrs,
|
|
dosmode, st->st_mode, compsize, uncompsize, commentsize);
|
|
elfwriter_appendsym(elf, gc(xasprintf("%s%s", "zip+cdir:", name)),
|
|
ELF64_ST_INFO(STB_LOCAL, STT_OBJECT), STV_DEFAULT, 0,
|
|
kZipCdirHdrLinkableSize);
|
|
elfwriter_appendrela(elf, kZipCfileOffsetOffset, lfilesym, R_X86_64_32,
|
|
-IMAGE_BASE_VIRTUAL);
|
|
elfwriter_commit(elf, kZipCdirHdrLinkableSize);
|
|
elfwriter_finishsection(elf);
|
|
}
|
|
|
|
void ProcessFile(struct ElfWriter *elf, const char *path) {
|
|
int fd;
|
|
void *map;
|
|
size_t pathlen;
|
|
struct stat st;
|
|
pathlen = strlen(path);
|
|
CHECK_NE(-1, (fd = open(path, O_RDONLY)));
|
|
CHECK_NE(-1, fstat(fd, &st));
|
|
if (st.st_size) {
|
|
CHECK_NE(MAP_FAILED,
|
|
(map = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0)));
|
|
CHECK_NE(-1, close(fd));
|
|
} else {
|
|
map = NULL;
|
|
}
|
|
EmitZip(elf, path, pathlen, map, &st);
|
|
CHECK_NE(-1, munmap(map, st.st_size));
|
|
}
|
|
|
|
void PullEndOfCentralDirectoryIntoLinkage(struct ElfWriter *elf) {
|
|
elfwriter_align(elf, 1, 0);
|
|
elfwriter_startsection(elf, ".yoink", SHT_PROGBITS,
|
|
SHF_ALLOC | SHF_EXECINSTR);
|
|
elfwriter_yoink(elf, yoink_);
|
|
elfwriter_finishsection(elf);
|
|
}
|
|
|
|
void CheckFilenameKosher(const char *path) {
|
|
CHECK_LE(strlen(path), PATH_MAX);
|
|
CHECK(!startswith(path, "/"));
|
|
CHECK(!strstr(path, ".."));
|
|
}
|
|
|
|
void zipobj(int argc, char **argv) {
|
|
size_t i;
|
|
struct ElfWriter *elf;
|
|
CHECK_LT(argc, UINT16_MAX / 3 - 64); /* ELF 64k section limit */
|
|
GetOpts(&argc, &argv);
|
|
for (i = 0; i < argc; ++i) CheckFilenameKosher(argv[i]);
|
|
elf = elfwriter_open(outpath_, 0644);
|
|
elfwriter_cargoculting(elf);
|
|
for (i = 0; i < argc; ++i) ProcessFile(elf, argv[i]);
|
|
PullEndOfCentralDirectoryIntoLinkage(elf);
|
|
elfwriter_close(elf);
|
|
}
|
|
|
|
int main(int argc, char **argv) {
|
|
zipobj(argc, argv);
|
|
return 0;
|
|
}
|