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-rw-r--r--src/compress.c1215
1 files changed, 1215 insertions, 0 deletions
diff --git a/src/compress.c b/src/compress.c
new file mode 100644
index 0000000..282f2a3
--- /dev/null
+++ b/src/compress.c
@@ -0,0 +1,1215 @@
+/*
+ * Copyright (c) Ian F. Darwin 1986-1995.
+ * Software written by Ian F. Darwin and others;
+ * maintained 1995-present by Christos Zoulas and others.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice immediately at the beginning of the file, without modification,
+ * this list of conditions, and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+/*
+ * compress routines:
+ * zmagic() - returns 0 if not recognized, uncompresses and prints
+ * information if recognized
+ * uncompress(method, old, n, newch) - uncompress old into new,
+ * using method, return sizeof new
+ */
+#include "file.h"
+
+#ifndef lint
+FILE_RCSID("@(#)$File: compress.c,v 1.154 2022/12/26 17:35:45 christos Exp $")
+#endif
+
+#include "magic.h"
+#include <stdlib.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_SPAWN_H
+#include <spawn.h>
+#endif
+#include <string.h>
+#include <errno.h>
+#include <ctype.h>
+#include <stdarg.h>
+#include <signal.h>
+#ifndef HAVE_SIG_T
+typedef void (*sig_t)(int);
+#endif /* HAVE_SIG_T */
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+#if defined(HAVE_SYS_TIME_H)
+#include <sys/time.h>
+#endif
+
+#if defined(HAVE_ZLIB_H) && defined(ZLIBSUPPORT)
+#define BUILTIN_DECOMPRESS
+#include <zlib.h>
+#endif
+
+#if defined(HAVE_BZLIB_H) && defined(BZLIBSUPPORT)
+#define BUILTIN_BZLIB
+#include <bzlib.h>
+#endif
+
+#if defined(HAVE_LZMA_H) && defined(XZLIBSUPPORT)
+#define BUILTIN_XZLIB
+#include <lzma.h>
+#endif
+
+#if defined(HAVE_ZSTD_H) && defined(ZSTDLIBSUPPORT)
+#define BUILTIN_ZSTDLIB
+#include <zstd.h>
+#include <zstd_errors.h>
+#endif
+
+#if defined(HAVE_LZLIB_H) && defined(LZLIBSUPPORT)
+#define BUILTIN_LZLIB
+#include <lzlib.h>
+#endif
+
+#ifdef DEBUG
+int tty = -1;
+#define DPRINTF(...) do { \
+ if (tty == -1) \
+ tty = open("/dev/tty", O_RDWR); \
+ if (tty == -1) \
+ abort(); \
+ dprintf(tty, __VA_ARGS__); \
+} while (/*CONSTCOND*/0)
+#else
+#define DPRINTF(...)
+#endif
+
+#ifdef ZLIBSUPPORT
+/*
+ * The following python code is not really used because ZLIBSUPPORT is only
+ * defined if we have a built-in zlib, and the built-in zlib handles that.
+ * That is not true for android where we have zlib.h and not -lz.
+ */
+static const char zlibcode[] =
+ "import sys, zlib; sys.stdout.write(zlib.decompress(sys.stdin.read()))";
+
+static const char *zlib_args[] = { "python", "-c", zlibcode, NULL };
+
+static int
+zlibcmp(const unsigned char *buf)
+{
+ unsigned short x = 1;
+ unsigned char *s = CAST(unsigned char *, CAST(void *, &x));
+
+ if ((buf[0] & 0xf) != 8 || (buf[0] & 0x80) != 0)
+ return 0;
+ if (s[0] != 1) /* endianness test */
+ x = buf[0] | (buf[1] << 8);
+ else
+ x = buf[1] | (buf[0] << 8);
+ if (x % 31)
+ return 0;
+ return 1;
+}
+#endif
+
+static int
+lzmacmp(const unsigned char *buf)
+{
+ if (buf[0] != 0x5d || buf[1] || buf[2])
+ return 0;
+ if (buf[12] && buf[12] != 0xff)
+ return 0;
+ return 1;
+}
+
+#define gzip_flags "-cd"
+#define lrzip_flags "-do"
+#define lzip_flags gzip_flags
+
+static const char *gzip_args[] = {
+ "gzip", gzip_flags, NULL
+};
+static const char *uncompress_args[] = {
+ "uncompress", "-c", NULL
+};
+static const char *bzip2_args[] = {
+ "bzip2", "-cd", NULL
+};
+static const char *lzip_args[] = {
+ "lzip", lzip_flags, NULL
+};
+static const char *xz_args[] = {
+ "xz", "-cd", NULL
+};
+static const char *lrzip_args[] = {
+ "lrzip", lrzip_flags, NULL
+};
+static const char *lz4_args[] = {
+ "lz4", "-cd", NULL
+};
+static const char *zstd_args[] = {
+ "zstd", "-cd", NULL
+};
+
+#define do_zlib NULL
+#define do_bzlib NULL
+
+file_private const struct {
+ union {
+ const char *magic;
+ int (*func)(const unsigned char *);
+ } u;
+ int maglen;
+ const char **argv;
+ void *unused;
+} compr[] = {
+#define METH_FROZEN 2
+#define METH_BZIP 7
+#define METH_XZ 9
+#define METH_LZIP 8
+#define METH_ZSTD 12
+#define METH_LZMA 13
+#define METH_ZLIB 14
+ { { .magic = "\037\235" }, 2, gzip_args, NULL }, /* 0, compressed */
+ /* Uncompress can get stuck; so use gzip first if we have it
+ * Idea from Damien Clark, thanks! */
+ { { .magic = "\037\235" }, 2, uncompress_args, NULL },/* 1, compressed */
+ { { .magic = "\037\213" }, 2, gzip_args, do_zlib },/* 2, gzipped */
+ { { .magic = "\037\236" }, 2, gzip_args, NULL }, /* 3, frozen */
+ { { .magic = "\037\240" }, 2, gzip_args, NULL }, /* 4, SCO LZH */
+ /* the standard pack utilities do not accept standard input */
+ { { .magic = "\037\036" }, 2, gzip_args, NULL }, /* 5, packed */
+ { { .magic = "PK\3\4" }, 4, gzip_args, NULL }, /* 6, pkziped */
+ /* ...only first file examined */
+ { { .magic = "BZh" }, 3, bzip2_args, do_bzlib },/* 7, bzip2-ed */
+ { { .magic = "LZIP" }, 4, lzip_args, NULL }, /* 8, lzip-ed */
+ { { .magic = "\3757zXZ\0" },6, xz_args, NULL }, /* 9, XZ Util */
+ { { .magic = "LRZI" }, 4, lrzip_args, NULL }, /* 10, LRZIP */
+ { { .magic = "\004\"M\030" },4, lz4_args, NULL }, /* 11, LZ4 */
+ { { .magic = "\x28\xB5\x2F\xFD" }, 4, zstd_args, NULL },/* 12, zstd */
+ { { .func = lzmacmp }, -13, xz_args, NULL }, /* 13, lzma */
+#ifdef ZLIBSUPPORT
+ { { .func = zlibcmp }, -2, zlib_args, NULL }, /* 14, zlib */
+#endif
+};
+
+#define OKDATA 0
+#define NODATA 1
+#define ERRDATA 2
+
+file_private ssize_t swrite(int, const void *, size_t);
+#if HAVE_FORK
+file_private size_t ncompr = __arraycount(compr);
+file_private int uncompressbuf(int, size_t, size_t, int, const unsigned char *,
+ unsigned char **, size_t *);
+#ifdef BUILTIN_DECOMPRESS
+file_private int uncompresszlib(const unsigned char *, unsigned char **, size_t,
+ size_t *, int);
+file_private int uncompressgzipped(const unsigned char *, unsigned char **, size_t,
+ size_t *, int);
+#endif
+#ifdef BUILTIN_BZLIB
+file_private int uncompressbzlib(const unsigned char *, unsigned char **, size_t,
+ size_t *, int);
+#endif
+#ifdef BUILTIN_XZLIB
+file_private int uncompressxzlib(const unsigned char *, unsigned char **, size_t,
+ size_t *, int);
+#endif
+#ifdef BUILTIN_ZSTDLIB
+file_private int uncompresszstd(const unsigned char *, unsigned char **, size_t,
+ size_t *, int);
+#endif
+#ifdef BUILTIN_LZLIB
+file_private int uncompresslzlib(const unsigned char *, unsigned char **, size_t,
+ size_t *, int);
+#endif
+
+static int makeerror(unsigned char **, size_t *, const char *, ...)
+ __attribute__((__format__(__printf__, 3, 4)));
+file_private const char *methodname(size_t);
+
+file_private int
+format_decompression_error(struct magic_set *ms, size_t i, unsigned char *buf)
+{
+ unsigned char *p;
+ int mime = ms->flags & MAGIC_MIME;
+
+ if (!mime)
+ return file_printf(ms, "ERROR:[%s: %s]", methodname(i), buf);
+
+ for (p = buf; *p; p++)
+ if (!isalnum(*p))
+ *p = '-';
+
+ return file_printf(ms, "application/x-decompression-error-%s-%s",
+ methodname(i), buf);
+}
+
+file_protected int
+file_zmagic(struct magic_set *ms, const struct buffer *b, const char *name)
+{
+ unsigned char *newbuf = NULL;
+ size_t i, nsz;
+ char *rbuf;
+ file_pushbuf_t *pb;
+ int urv, prv, rv = 0;
+ int mime = ms->flags & MAGIC_MIME;
+ int fd = b->fd;
+ const unsigned char *buf = CAST(const unsigned char *, b->fbuf);
+ size_t nbytes = b->flen;
+ int sa_saved = 0;
+ struct sigaction sig_act;
+
+ if ((ms->flags & MAGIC_COMPRESS) == 0)
+ return 0;
+
+ for (i = 0; i < ncompr; i++) {
+ int zm;
+ if (nbytes < CAST(size_t, abs(compr[i].maglen)))
+ continue;
+ if (compr[i].maglen < 0) {
+ zm = (*compr[i].u.func)(buf);
+ } else {
+ zm = memcmp(buf, compr[i].u.magic,
+ CAST(size_t, compr[i].maglen)) == 0;
+ }
+
+ if (!zm)
+ continue;
+
+ /* Prevent SIGPIPE death if child dies unexpectedly */
+ if (!sa_saved) {
+ //We can use sig_act for both new and old, but
+ struct sigaction new_act;
+ memset(&new_act, 0, sizeof(new_act));
+ new_act.sa_handler = SIG_IGN;
+ sa_saved = sigaction(SIGPIPE, &new_act, &sig_act) != -1;
+ }
+
+ nsz = nbytes;
+ free(newbuf);
+ urv = uncompressbuf(fd, ms->bytes_max, i,
+ (ms->flags & MAGIC_NO_COMPRESS_FORK), buf, &newbuf, &nsz);
+ DPRINTF("uncompressbuf = %d, %s, %" SIZE_T_FORMAT "u\n", urv,
+ (char *)newbuf, nsz);
+ switch (urv) {
+ case OKDATA:
+ case ERRDATA:
+ ms->flags &= ~MAGIC_COMPRESS;
+ if (urv == ERRDATA)
+ prv = format_decompression_error(ms, i, newbuf);
+ else
+ prv = file_buffer(ms, -1, NULL, name, newbuf,
+ nsz);
+ if (prv == -1)
+ goto error;
+ rv = 1;
+ if ((ms->flags & MAGIC_COMPRESS_TRANSP) != 0)
+ goto out;
+ if (mime != MAGIC_MIME && mime != 0)
+ goto out;
+ if ((file_printf(ms,
+ mime ? " compressed-encoding=" : " (")) == -1)
+ goto error;
+ if ((pb = file_push_buffer(ms)) == NULL)
+ goto error;
+ /*
+ * XXX: If file_buffer fails here, we overwrite
+ * the compressed text. FIXME.
+ */
+ if (file_buffer(ms, -1, NULL, NULL, buf, nbytes) == -1)
+ {
+ if (file_pop_buffer(ms, pb) != NULL)
+ abort();
+ goto error;
+ }
+ if ((rbuf = file_pop_buffer(ms, pb)) != NULL) {
+ if (file_printf(ms, "%s", rbuf) == -1) {
+ free(rbuf);
+ goto error;
+ }
+ free(rbuf);
+ }
+ if (!mime && file_printf(ms, ")") == -1)
+ goto error;
+ /*FALLTHROUGH*/
+ case NODATA:
+ break;
+ default:
+ abort();
+ /*NOTREACHED*/
+ error:
+ rv = -1;
+ break;
+ }
+ }
+out:
+ DPRINTF("rv = %d\n", rv);
+
+ if (sa_saved && sig_act.sa_handler != SIG_IGN)
+ (void)sigaction(SIGPIPE, &sig_act, NULL);
+
+ free(newbuf);
+ ms->flags |= MAGIC_COMPRESS;
+ DPRINTF("Zmagic returns %d\n", rv);
+ return rv;
+}
+#endif
+/*
+ * `safe' write for sockets and pipes.
+ */
+file_private ssize_t
+swrite(int fd, const void *buf, size_t n)
+{
+ ssize_t rv;
+ size_t rn = n;
+
+ do
+ switch (rv = write(fd, buf, n)) {
+ case -1:
+ if (errno == EINTR)
+ continue;
+ return -1;
+ default:
+ n -= rv;
+ buf = CAST(const char *, buf) + rv;
+ break;
+ }
+ while (n > 0);
+ return rn;
+}
+
+
+/*
+ * `safe' read for sockets and pipes.
+ */
+file_protected ssize_t
+sread(int fd, void *buf, size_t n, int canbepipe __attribute__((__unused__)))
+{
+ ssize_t rv;
+#ifdef FIONREAD
+ int t = 0;
+#endif
+ size_t rn = n;
+
+ if (fd == STDIN_FILENO)
+ goto nocheck;
+
+#ifdef FIONREAD
+ if (canbepipe && (ioctl(fd, FIONREAD, &t) == -1 || t == 0)) {
+#ifdef FD_ZERO
+ ssize_t cnt;
+ for (cnt = 0;; cnt++) {
+ fd_set check;
+ struct timeval tout = {0, 100 * 1000};
+ int selrv;
+
+ FD_ZERO(&check);
+ FD_SET(fd, &check);
+
+ /*
+ * Avoid soft deadlock: do not read if there
+ * is nothing to read from sockets and pipes.
+ */
+ selrv = select(fd + 1, &check, NULL, NULL, &tout);
+ if (selrv == -1) {
+ if (errno == EINTR || errno == EAGAIN)
+ continue;
+ } else if (selrv == 0 && cnt >= 5) {
+ return 0;
+ } else
+ break;
+ }
+#endif
+ (void)ioctl(fd, FIONREAD, &t);
+ }
+
+ if (t > 0 && CAST(size_t, t) < n) {
+ n = t;
+ rn = n;
+ }
+#endif
+
+nocheck:
+ do
+ switch ((rv = read(fd, buf, n))) {
+ case -1:
+ if (errno == EINTR)
+ continue;
+ return -1;
+ case 0:
+ return rn - n;
+ default:
+ n -= rv;
+ buf = CAST(char *, CCAST(void *, buf)) + rv;
+ break;
+ }
+ while (n > 0);
+ return rn;
+}
+
+file_protected int
+file_pipe2file(struct magic_set *ms, int fd, const void *startbuf,
+ size_t nbytes)
+{
+ char buf[4096];
+ ssize_t r;
+ int tfd;
+
+#ifdef WIN32
+ const char *t;
+ buf[0] = '\0';
+ if ((t = getenv("TEMP")) != NULL)
+ (void)strlcpy(buf, t, sizeof(buf));
+ else if ((t = getenv("TMP")) != NULL)
+ (void)strlcpy(buf, t, sizeof(buf));
+ else if ((t = getenv("TMPDIR")) != NULL)
+ (void)strlcpy(buf, t, sizeof(buf));
+ if (buf[0] != '\0')
+ (void)strlcat(buf, "/", sizeof(buf));
+ (void)strlcat(buf, "file.XXXXXX", sizeof(buf));
+#else
+ (void)strlcpy(buf, "/tmp/file.XXXXXX", sizeof(buf));
+#endif
+#ifndef HAVE_MKSTEMP
+ {
+ char *ptr = mktemp(buf);
+ tfd = open(ptr, O_RDWR|O_TRUNC|O_EXCL|O_CREAT, 0600);
+ r = errno;
+ (void)unlink(ptr);
+ errno = r;
+ }
+#else
+ {
+ int te;
+ mode_t ou = umask(0);
+ tfd = mkstemp(buf);
+ (void)umask(ou);
+ te = errno;
+ (void)unlink(buf);
+ errno = te;
+ }
+#endif
+ if (tfd == -1) {
+ file_error(ms, errno,
+ "cannot create temporary file for pipe copy");
+ return -1;
+ }
+
+ if (swrite(tfd, startbuf, nbytes) != CAST(ssize_t, nbytes))
+ r = 1;
+ else {
+ while ((r = sread(fd, buf, sizeof(buf), 1)) > 0)
+ if (swrite(tfd, buf, CAST(size_t, r)) != r)
+ break;
+ }
+
+ switch (r) {
+ case -1:
+ file_error(ms, errno, "error copying from pipe to temp file");
+ return -1;
+ case 0:
+ break;
+ default:
+ file_error(ms, errno, "error while writing to temp file");
+ return -1;
+ }
+
+ /*
+ * We duplicate the file descriptor, because fclose on a
+ * tmpfile will delete the file, but any open descriptors
+ * can still access the phantom inode.
+ */
+ if ((fd = dup2(tfd, fd)) == -1) {
+ file_error(ms, errno, "could not dup descriptor for temp file");
+ return -1;
+ }
+ (void)close(tfd);
+ if (lseek(fd, CAST(off_t, 0), SEEK_SET) == CAST(off_t, -1)) {
+ file_badseek(ms);
+ return -1;
+ }
+ return fd;
+}
+#if HAVE_FORK
+#ifdef BUILTIN_DECOMPRESS
+
+#define FHCRC (1 << 1)
+#define FEXTRA (1 << 2)
+#define FNAME (1 << 3)
+#define FCOMMENT (1 << 4)
+
+
+file_private int
+uncompressgzipped(const unsigned char *old, unsigned char **newch,
+ size_t bytes_max, size_t *n, int extra __attribute__((__unused__)))
+{
+ unsigned char flg;
+ size_t data_start = 10;
+
+ if (*n < 4) {
+ goto err;
+ }
+
+ flg = old[3];
+
+ if (flg & FEXTRA) {
+ if (data_start + 1 >= *n)
+ goto err;
+ data_start += 2 + old[data_start] + old[data_start + 1] * 256;
+ }
+ if (flg & FNAME) {
+ while(data_start < *n && old[data_start])
+ data_start++;
+ data_start++;
+ }
+ if (flg & FCOMMENT) {
+ while(data_start < *n && old[data_start])
+ data_start++;
+ data_start++;
+ }
+ if (flg & FHCRC)
+ data_start += 2;
+
+ if (data_start >= *n)
+ goto err;
+
+ *n -= data_start;
+ old += data_start;
+ return uncompresszlib(old, newch, bytes_max, n, 0);
+err:
+ return makeerror(newch, n, "File too short");
+}
+
+file_private int
+uncompresszlib(const unsigned char *old, unsigned char **newch,
+ size_t bytes_max, size_t *n, int zlib)
+{
+ int rc;
+ z_stream z;
+
+ z.next_in = CCAST(Bytef *, old);
+ z.avail_in = CAST(uint32_t, *n);
+ z.next_out = *newch;
+ z.avail_out = CAST(unsigned int, bytes_max);
+ z.zalloc = Z_NULL;
+ z.zfree = Z_NULL;
+ z.opaque = Z_NULL;
+
+ /* LINTED bug in header macro */
+ rc = zlib ? inflateInit(&z) : inflateInit2(&z, -15);
+ if (rc != Z_OK)
+ goto err;
+
+ rc = inflate(&z, Z_SYNC_FLUSH);
+ if (rc != Z_OK && rc != Z_STREAM_END) {
+ inflateEnd(&z);
+ goto err;
+ }
+
+ *n = CAST(size_t, z.total_out);
+ rc = inflateEnd(&z);
+ if (rc != Z_OK)
+ goto err;
+
+ /* let's keep the nul-terminate tradition */
+ (*newch)[*n] = '\0';
+
+ return OKDATA;
+err:
+ return makeerror(newch, n, "%s", z.msg ? z.msg : zError(rc));
+}
+#endif
+
+#ifdef BUILTIN_BZLIB
+file_private int
+uncompressbzlib(const unsigned char *old, unsigned char **newch,
+ size_t bytes_max, size_t *n, int extra __attribute__((__unused__)))
+{
+ int rc;
+ bz_stream bz;
+
+ memset(&bz, 0, sizeof(bz));
+ rc = BZ2_bzDecompressInit(&bz, 0, 0);
+ if (rc != BZ_OK)
+ goto err;
+
+ bz.next_in = CCAST(char *, RCAST(const char *, old));
+ bz.avail_in = CAST(uint32_t, *n);
+ bz.next_out = RCAST(char *, *newch);
+ bz.avail_out = CAST(unsigned int, bytes_max);
+
+ rc = BZ2_bzDecompress(&bz);
+ if (rc != BZ_OK && rc != BZ_STREAM_END) {
+ BZ2_bzDecompressEnd(&bz);
+ goto err;
+ }
+
+ /* Assume byte_max is within 32bit */
+ /* assert(bz.total_out_hi32 == 0); */
+ *n = CAST(size_t, bz.total_out_lo32);
+ rc = BZ2_bzDecompressEnd(&bz);
+ if (rc != BZ_OK)
+ goto err;
+
+ /* let's keep the nul-terminate tradition */
+ (*newch)[*n] = '\0';
+
+ return OKDATA;
+err:
+ return makeerror(newch, n, "bunzip error %d", rc);
+}
+#endif
+
+#ifdef BUILTIN_XZLIB
+file_private int
+uncompressxzlib(const unsigned char *old, unsigned char **newch,
+ size_t bytes_max, size_t *n, int extra __attribute__((__unused__)))
+{
+ int rc;
+ lzma_stream xz;
+
+ memset(&xz, 0, sizeof(xz));
+ rc = lzma_auto_decoder(&xz, UINT64_MAX, 0);
+ if (rc != LZMA_OK)
+ goto err;
+
+ xz.next_in = CCAST(const uint8_t *, old);
+ xz.avail_in = CAST(uint32_t, *n);
+ xz.next_out = RCAST(uint8_t *, *newch);
+ xz.avail_out = CAST(unsigned int, bytes_max);
+
+ rc = lzma_code(&xz, LZMA_RUN);
+ if (rc != LZMA_OK && rc != LZMA_STREAM_END) {
+ lzma_end(&xz);
+ goto err;
+ }
+
+ *n = CAST(size_t, xz.total_out);
+
+ lzma_end(&xz);
+
+ /* let's keep the nul-terminate tradition */
+ (*newch)[*n] = '\0';
+
+ return OKDATA;
+err:
+ return makeerror(newch, n, "unxz error %d", rc);
+}
+#endif
+
+#ifdef BUILTIN_ZSTDLIB
+file_private int
+uncompresszstd(const unsigned char *old, unsigned char **newch,
+ size_t bytes_max, size_t *n, int extra __attribute__((__unused__)))
+{
+ size_t rc;
+ ZSTD_DStream *zstd;
+ ZSTD_inBuffer in;
+ ZSTD_outBuffer out;
+
+ if ((zstd = ZSTD_createDStream()) == NULL) {
+ return makeerror(newch, n, "No ZSTD decompression stream, %s",
+ strerror(errno));
+ }
+
+ rc = ZSTD_DCtx_reset(zstd, ZSTD_reset_session_only);
+ if (ZSTD_isError(rc))
+ goto err;
+
+ in.src = CCAST(const void *, old);
+ in.size = *n;
+ in.pos = 0;
+ out.dst = RCAST(void *, *newch);
+ out.size = bytes_max;
+ out.pos = 0;
+
+ rc = ZSTD_decompressStream(zstd, &out, &in);
+ if (ZSTD_isError(rc))
+ goto err;
+
+ *n = out.pos;
+
+ ZSTD_freeDStream(zstd);
+
+ /* let's keep the nul-terminate tradition */
+ (*newch)[*n] = '\0';
+
+ return OKDATA;
+err:
+ ZSTD_freeDStream(zstd);
+ return makeerror(newch, n, "zstd error %d", ZSTD_getErrorCode(rc));
+}
+#endif
+
+#ifdef BUILTIN_LZLIB
+file_private int
+uncompresslzlib(const unsigned char *old, unsigned char **newch,
+ size_t bytes_max, size_t *n, int extra __attribute__((__unused__)))
+{
+ enum LZ_Errno err;
+ size_t old_remaining = *n;
+ size_t new_remaining = bytes_max;
+ size_t total_read = 0;
+ unsigned char *bufp;
+ struct LZ_Decoder *dec;
+
+ bufp = *newch;
+
+ dec = LZ_decompress_open();
+ if (!dec) {
+ return makeerror(newch, n, "unable to allocate LZ_Decoder");
+ }
+ if (LZ_decompress_errno(dec) != LZ_ok)
+ goto err;
+
+ for (;;) {
+ // LZ_decompress_read() stops at member boundaries, so we may
+ // have more than one successful read after writing all data
+ // we have.
+ if (old_remaining > 0) {
+ int wr = LZ_decompress_write(dec, old, old_remaining);
+ if (wr < 0)
+ goto err;
+ old_remaining -= wr;
+ old += wr;
+ }
+
+ int rd = LZ_decompress_read(dec, bufp, new_remaining);
+ if (rd > 0) {
+ new_remaining -= rd;
+ bufp += rd;
+ total_read += rd;
+ }
+
+ if (rd < 0 || LZ_decompress_errno(dec) != LZ_ok)
+ goto err;
+ if (new_remaining == 0)
+ break;
+ if (old_remaining == 0 && rd == 0)
+ break;
+ }
+
+ LZ_decompress_close(dec);
+ *n = total_read;
+
+ /* let's keep the nul-terminate tradition */
+ *bufp = '\0';
+
+ return OKDATA;
+err:
+ err = LZ_decompress_errno(dec);
+ LZ_decompress_close(dec);
+ return makeerror(newch, n, "lzlib error: %s", LZ_strerror(err));
+}
+#endif
+
+
+static int
+makeerror(unsigned char **buf, size_t *len, const char *fmt, ...)
+{
+ char *msg;
+ va_list ap;
+ int rv;
+
+ free(*buf);
+ va_start(ap, fmt);
+ rv = vasprintf(&msg, fmt, ap);
+ va_end(ap);
+ if (rv < 0) {
+ *buf = NULL;
+ *len = 0;
+ return NODATA;
+ }
+ *buf = RCAST(unsigned char *, msg);
+ *len = strlen(msg);
+ return ERRDATA;
+}
+
+static void
+closefd(int *fd, size_t i)
+{
+ if (fd[i] == -1)
+ return;
+ (void) close(fd[i]);
+ fd[i] = -1;
+}
+
+static void
+closep(int *fd)
+{
+ size_t i;
+ for (i = 0; i < 2; i++)
+ closefd(fd, i);
+}
+
+static void
+movedesc(void *v, int i, int fd)
+{
+ if (fd == i)
+ return; /* "no dup was necessary" */
+#ifdef HAVE_POSIX_SPAWNP
+ posix_spawn_file_actions_t *fa = RCAST(posix_spawn_file_actions_t *, v);
+ posix_spawn_file_actions_adddup2(fa, fd, i);
+ posix_spawn_file_actions_addclose(fa, fd);
+#else
+ if (dup2(fd, i) == -1) {
+ DPRINTF("dup(%d, %d) failed (%s)\n", fd, i, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ close(v ? fd : fd);
+#endif
+}
+
+static void
+closedesc(void *v, int fd)
+{
+#ifdef HAVE_POSIX_SPAWNP
+ posix_spawn_file_actions_t *fa = RCAST(posix_spawn_file_actions_t *, v);
+ posix_spawn_file_actions_addclose(fa, fd);
+#else
+ close(v ? fd : fd);
+#endif
+}
+
+static void
+handledesc(void *v, int fd, int fdp[3][2])
+{
+ if (fd != -1) {
+ (void) lseek(fd, CAST(off_t, 0), SEEK_SET);
+ movedesc(v, STDIN_FILENO, fd);
+ } else {
+ movedesc(v, STDIN_FILENO, fdp[STDIN_FILENO][0]);
+ if (fdp[STDIN_FILENO][1] > 2)
+ closedesc(v, fdp[STDIN_FILENO][1]);
+ }
+
+ file_clear_closexec(STDIN_FILENO);
+
+///FIXME: if one of the fdp[i][j] is 0 or 1, this can bomb spectacularly
+ movedesc(v, STDOUT_FILENO, fdp[STDOUT_FILENO][1]);
+ if (fdp[STDOUT_FILENO][0] > 2)
+ closedesc(v, fdp[STDOUT_FILENO][0]);
+
+ file_clear_closexec(STDOUT_FILENO);
+
+ movedesc(v, STDERR_FILENO, fdp[STDERR_FILENO][1]);
+ if (fdp[STDERR_FILENO][0] > 2)
+ closedesc(v, fdp[STDERR_FILENO][0]);
+
+ file_clear_closexec(STDERR_FILENO);
+}
+
+static pid_t
+writechild(int fd, const void *old, size_t n)
+{
+ pid_t pid;
+
+ /*
+ * fork again, to avoid blocking because both
+ * pipes filled
+ */
+ pid = fork();
+ if (pid == -1) {
+ DPRINTF("Fork failed (%s)\n", strerror(errno));
+ return -1;
+ }
+ if (pid == 0) {
+ /* child */
+ if (swrite(fd, old, n) != CAST(ssize_t, n)) {
+ DPRINTF("Write failed (%s)\n", strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+ exit(EXIT_SUCCESS);
+ }
+ /* parent */
+ return pid;
+}
+
+static ssize_t
+filter_error(unsigned char *ubuf, ssize_t n)
+{
+ char *p;
+ char *buf;
+
+ ubuf[n] = '\0';
+ buf = RCAST(char *, ubuf);
+ while (isspace(CAST(unsigned char, *buf)))
+ buf++;
+ DPRINTF("Filter error[[[%s]]]\n", buf);
+ if ((p = strchr(CAST(char *, buf), '\n')) != NULL)
+ *p = '\0';
+ if ((p = strchr(CAST(char *, buf), ';')) != NULL)
+ *p = '\0';
+ if ((p = strrchr(CAST(char *, buf), ':')) != NULL) {
+ ++p;
+ while (isspace(CAST(unsigned char, *p)))
+ p++;
+ n = strlen(p);
+ memmove(ubuf, p, CAST(size_t, n + 1));
+ }
+ DPRINTF("Filter error after[[[%s]]]\n", (char *)ubuf);
+ if (islower(*ubuf))
+ *ubuf = toupper(*ubuf);
+ return n;
+}
+
+file_private const char *
+methodname(size_t method)
+{
+ switch (method) {
+#ifdef BUILTIN_DECOMPRESS
+ case METH_FROZEN:
+ case METH_ZLIB:
+ return "zlib";
+#endif
+#ifdef BUILTIN_BZLIB
+ case METH_BZIP:
+ return "bzlib";
+#endif
+#ifdef BUILTIN_XZLIB
+ case METH_XZ:
+ case METH_LZMA:
+ return "xzlib";
+#endif
+#ifdef BUILTIN_ZSTDLIB
+ case METH_ZSTD:
+ return "zstd";
+#endif
+#ifdef BUILTIN_LZLIB
+ case METH_LZIP:
+ return "lzlib";
+#endif
+ default:
+ return compr[method].argv[0];
+ }
+}
+
+file_private int (*
+getdecompressor(size_t method))(const unsigned char *, unsigned char **, size_t,
+ size_t *, int)
+{
+ switch (method) {
+#ifdef BUILTIN_DECOMPRESS
+ case METH_FROZEN:
+ return uncompressgzipped;
+ case METH_ZLIB:
+ return uncompresszlib;
+#endif
+#ifdef BUILTIN_BZLIB
+ case METH_BZIP:
+ return uncompressbzlib;
+#endif
+#ifdef BUILTIN_XZLIB
+ case METH_XZ:
+ case METH_LZMA:
+ return uncompressxzlib;
+#endif
+#ifdef BUILTIN_ZSTDLIB
+ case METH_ZSTD:
+ return uncompresszstd;
+#endif
+#ifdef BUILTIN_LZLIB
+ case METH_LZIP:
+ return uncompresslzlib;
+#endif
+ default:
+ return NULL;
+ }
+}
+
+file_private int
+uncompressbuf(int fd, size_t bytes_max, size_t method, int nofork,
+ const unsigned char *old, unsigned char **newch, size_t* n)
+{
+ int fdp[3][2];
+ int status, rv, w;
+ pid_t pid;
+ pid_t writepid = -1;
+ size_t i;
+ ssize_t r;
+ char *const *args;
+#ifdef HAVE_POSIX_SPAWNP
+ posix_spawn_file_actions_t fa;
+#endif
+ int (*decompress)(const unsigned char *, unsigned char **,
+ size_t, size_t *, int) = getdecompressor(method);
+
+ *newch = CAST(unsigned char *, malloc(bytes_max + 1));
+ if (*newch == NULL)
+ return makeerror(newch, n, "No buffer, %s", strerror(errno));
+
+ if (decompress) {
+ if (nofork) {
+ return makeerror(newch, n,
+ "Fork is required to uncompress, but disabled");
+ }
+ return (*decompress)(old, newch, bytes_max, n, 1);
+ }
+
+ (void)fflush(stdout);
+ (void)fflush(stderr);
+
+ for (i = 0; i < __arraycount(fdp); i++)
+ fdp[i][0] = fdp[i][1] = -1;
+
+ /*
+ * There are multithreaded users who run magic_file()
+ * from dozens of threads. If two parallel magic_file() calls
+ * analyze two large compressed files, both will spawn
+ * an uncompressing child here, which writes out uncompressed data.
+ * We read some portion, then close the pipe, then waitpid() the child.
+ * If uncompressed data is larger, child should get EPIPE and exit.
+ * However, with *parallel* calls OTHER child may unintentionally
+ * inherit pipe fds, thus keeping pipe open and making writes in
+ * our child block instead of failing with EPIPE!
+ * (For the bug to occur, two threads must mutually inherit their pipes,
+ * and both must have large outputs. Thus it happens not that often).
+ * To avoid this, be sure to create pipes with O_CLOEXEC.
+ */
+ if ((fd == -1 && file_pipe_closexec(fdp[STDIN_FILENO]) == -1) ||
+ file_pipe_closexec(fdp[STDOUT_FILENO]) == -1 ||
+ file_pipe_closexec(fdp[STDERR_FILENO]) == -1) {
+ closep(fdp[STDIN_FILENO]);
+ closep(fdp[STDOUT_FILENO]);
+ return makeerror(newch, n, "Cannot create pipe, %s",
+ strerror(errno));
+ }
+
+ args = RCAST(char *const *, RCAST(intptr_t, compr[method].argv));
+#ifdef HAVE_POSIX_SPAWNP
+ posix_spawn_file_actions_init(&fa);
+
+ handledesc(&fa, fd, fdp);
+
+ status = posix_spawnp(&pid, compr[method].argv[0], &fa, NULL,
+ args, NULL);
+
+ posix_spawn_file_actions_destroy(&fa);
+
+ if (status == -1) {
+ return makeerror(newch, n, "Cannot posix_spawn `%s', %s",
+ compr[method].argv[0], strerror(errno));
+ }
+#else
+ /* For processes with large mapped virtual sizes, vfork
+ * may be _much_ faster (10-100 times) than fork.
+ */
+ pid = vfork();
+ if (pid == -1) {
+ return makeerror(newch, n, "Cannot vfork, %s",
+ strerror(errno));
+ }
+ if (pid == 0) {
+ /* child */
+ /* Note: we are after vfork, do not modify memory
+ * in a way which confuses parent. In particular,
+ * do not modify fdp[i][j].
+ */
+ handledesc(NULL, fd, fdp);
+
+ (void)execvp(compr[method].argv[0], args);
+ dprintf(STDERR_FILENO, "exec `%s' failed, %s",
+ compr[method].argv[0], strerror(errno));
+ _exit(EXIT_FAILURE); /* _exit(), not exit(), because of vfork */
+ }
+#endif
+ /* parent */
+ /* Close write sides of child stdout/err pipes */
+ for (i = 1; i < __arraycount(fdp); i++)
+ closefd(fdp[i], 1);
+ /* Write the buffer data to child stdin, if we don't have fd */
+ if (fd == -1) {
+ closefd(fdp[STDIN_FILENO], 0);
+ writepid = writechild(fdp[STDIN_FILENO][1], old, *n);
+ if (writepid == (pid_t)-1) {
+ rv = makeerror(newch, n, "Write to child failed, %s",
+ strerror(errno));
+ goto err;
+ }
+ closefd(fdp[STDIN_FILENO], 1);
+ }
+
+ rv = OKDATA;
+ r = sread(fdp[STDOUT_FILENO][0], *newch, bytes_max, 0);
+ if (r < 0) {
+ rv = ERRDATA;
+ DPRINTF("Read stdout failed %d (%s)\n", fdp[STDOUT_FILENO][0],
+ strerror(errno));
+ goto err;
+ }
+ if (CAST(size_t, r) == bytes_max) {
+ /*
+ * close fd so that the child exits with sigpipe and ignore
+ * errors, otherwise we risk the child blocking and never
+ * exiting.
+ */
+ closefd(fdp[STDOUT_FILENO], 0);
+ goto ok;
+ }
+ if ((r = sread(fdp[STDERR_FILENO][0], *newch, bytes_max, 0)) > 0) {
+ rv = ERRDATA;
+ r = filter_error(*newch, r);
+ goto ok;
+ }
+ if (r == 0)
+ goto ok;
+ rv = makeerror(newch, n, "Read stderr failed, %s",
+ strerror(errno));
+ goto err;
+ok:
+ *n = r;
+ /* NUL terminate, as every buffer is handled here. */
+ (*newch)[*n] = '\0';
+err:
+ closefd(fdp[STDIN_FILENO], 1);
+ closefd(fdp[STDOUT_FILENO], 0);
+ closefd(fdp[STDERR_FILENO], 0);
+
+ w = waitpid(pid, &status, 0);
+wait_err:
+ if (w == -1) {
+ rv = makeerror(newch, n, "Wait failed, %s", strerror(errno));
+ DPRINTF("Child wait return %#x\n", status);
+ } else if (!WIFEXITED(status)) {
+ DPRINTF("Child not exited (%#x)\n", status);
+ } else if (WEXITSTATUS(status) != 0) {
+ DPRINTF("Child exited (%#x)\n", WEXITSTATUS(status));
+ }
+ if (writepid > 0) {
+ /* _After_ we know decompressor has exited, our input writer
+ * definitely will exit now (at worst, writing fails in it,
+ * since output fd is closed now on the reading size).
+ */
+ w = waitpid(writepid, &status, 0);
+ writepid = -1;
+ goto wait_err;
+ }
+
+ closefd(fdp[STDIN_FILENO], 0); //why? it is already closed here!
+ DPRINTF("Returning %p n=%" SIZE_T_FORMAT "u rv=%d\n", *newch, *n, rv);
+
+ return rv;
+}
+#endif
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 01:17:00 +0000