* This logic returns zero if any part of the signature fails. It
* also tries to Do The Right Thing if a very short buffer prevents us
* from verifying as much as we would like.
+ *
+ * <sigh> LZMA has a rather poor file signature. Zeros do not
+ * make good signature bytes as a rule, and the only non-zero byte
+ * here is an ASCII character. For example, an uncompressed tar
+ * archive whose first file is ']' would satisfy this check. It may
+ * be necessary to exclude LZMA from compression_all() because of
+ * this. Clients of libarchive would then have to explicitly enable
+ * LZMA checking instead of (or in addition to) compression_all() when
+ * they have other evidence (file name, command-line option) to go on.
*/
static int
lzma_reader_bid(struct archive_reader *self, const void *buff, size_t len)
(void)self; /* UNUSED */
+ buffer = (const unsigned char *)buff;
+
+
+ /* First byte of raw LZMA stream is always 0x5d. */
if (len < 1)
return (0);
-
- buffer = (const unsigned char *)buff;
bits_checked = 0;
- if (buffer[0] != 0x5d) /* Verify first ID byte. */
+ if (buffer[0] != 0x5d)
+ return (0);
+ bits_checked += 8;
+
+ /* Second through fifth bytes are dictionary code, stored in
+ * little-endian order. The two least-significant bytes are
+ * always zero. */
+ if (len < 2)
+ return (bits_checked);
+ if (buffer[1] != 0)
+ return (0);
+ bits_checked += 8;
+
+ if (len < 3)
+ return (bits_checked);
+ if (buffer[2] != 0)
return (0);
bits_checked += 8;
+ /* ??? TODO: Explain this. ??? */
+ if (len < 6)
+ return (bits_checked);
+ if (buffer[5] != 0)
+ return (0);
+ bits_checked += 8;
+
+ /* TODO: The above test is still very weak. It would be
+ * good to do better. */
+
return (bits_checked);
}
--- /dev/null
+/*-
+ * Copyright (c) 2008 Miklos Vajna
+ * All rights reserved.
+ *
+ * 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, 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(S) ``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(S) 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.
+ */
+#include "test.h"
+__FBSDID("$FreeBSD$");
+
+static unsigned char archive[] = {
+0x5d, 0x0, 0x0, 0x80, 0x0, 0x0, 0x28, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
+0x17, 0xb, 0xbc, 0x1c, 0x7d, 0x1, 0x95, 0xc0, 0x1d, 0x4a, 0x46, 0x9c,
+0x1c, 0xc5, 0x8, 0x82, 0x10, 0xed, 0x84, 0xf6, 0xea, 0x7a, 0xfe, 0x63,
+0x5a, 0x34, 0x5e, 0xf7, 0xc, 0x60, 0xd6, 0x8b, 0xc1, 0x47, 0xaf, 0x11,
+0x6f, 0x18, 0x94, 0x81, 0x74, 0x8a, 0xf8, 0x47, 0xcc, 0xdd, 0xc0, 0xd9,
+0x40, 0xa, 0xc3, 0xac, 0x43, 0x47, 0xb5, 0xac, 0x2b, 0x31, 0xd3, 0x6,
+0xa4, 0x2c, 0x44, 0x80, 0x24, 0x4b, 0xfe, 0x43, 0x22, 0x4e, 0x14, 0x30,
+0x7a, 0xef, 0x99, 0x6e, 0xf, 0x8b, 0xc1, 0x79, 0x93, 0x88, 0x54, 0x73,
+0x59, 0x3f, 0xc, 0xfb, 0xee, 0x9c, 0x83, 0x49, 0x93, 0x33, 0xad, 0x44,
+0xbe, 0x0};
+
+DEFINE_TEST(test_read_format_gtar_lzma)
+{
+ int r;
+
+ struct archive_entry *ae;
+ struct archive *a;
+ assert((a = archive_read_new()) != NULL);
+ assertEqualIntA(a, ARCHIVE_OK,
+ archive_read_support_compression_all(a));
+ assertEqualIntA(a, ARCHIVE_OK,
+ archive_read_support_compression_lzma(a));
+ assertEqualIntA(a, ARCHIVE_OK,
+ archive_read_support_format_all(a));
+ r = archive_read_open_memory(a, archive, sizeof(archive));
+ if (r != ARCHIVE_OK) {
+ skipping("Skipping LZMA compression check: %s",
+ archive_error_string(a));
+ goto finish;
+ }
+ assertEqualIntA(a, ARCHIVE_OK,
+ archive_read_next_header(a, &ae));
+ assertEqualInt(archive_compression(a), ARCHIVE_COMPRESSION_LZMA);
+ assertEqualInt(archive_format(a), ARCHIVE_FORMAT_TAR_GNUTAR);
+ assertEqualIntA(a, ARCHIVE_OK, archive_read_close(a));
+finish:
+#if ARCHIVE_VERSION_NUMBER < 2000000
+ archive_read_finish(a);
+#else
+ assertEqualInt(ARCHIVE_OK, archive_read_finish(a));
+#endif
+}
+
+
projects / thirdparty / libarchive.git / commitdiff
