If the Zip reader doesn't see a PK signature block

because there's inter-entry garbage, just scan forward
to find the next one.  This allows us to handle a lot
of Zip archives that have been modified in-place.

Thanks to: Gleb Kurtsou for sending me a sample archive

2 files changed, 43 insertions, 0 deletions

diff --git a/lib/libarchive/test/test_compat_zip.c b/lib/libarchive/test/test_compat_zip.c
index fefc6fe..adb377c 100644
--- a/lib/libarchive/test/test_compat_zip.c
+++ b/lib/libarchive/test/test_compat_zip.c
@@ -71,10 +71,43 @@ finish:
 #endif
 }
 
+/*
+ * Verify that we skip junk between entries.  The compat_zip_2.zip file
+ * has several bytes of junk between 'file1' and 'file2'.  Such
+ * junk is routinely introduced by some Zip writers when they manipulate
+ * existing zip archives.
+ */
+static void
+test_compat_zip_2(void)
+{
+	char name[] = "test_compat_zip_2.zip";
+	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_format_zip(a));
+	extract_reference_file(name);
+	assertEqualIntA(a, ARCHIVE_OK, archive_read_open_filename(a, name, 10240));
+
+	/* Read first entry. */
+	assertEqualIntA(a, ARCHIVE_OK, archive_read_next_header(a, &ae));
+	assertEqualString("file1", archive_entry_pathname(ae));
+
+	/* Read first entry. */
+	assertEqualIntA(a, ARCHIVE_OK, archive_read_next_header(a, &ae));
+	assertEqualString("file2", archive_entry_pathname(ae));
+
+	assertEqualIntA(a, ARCHIVE_EOF, archive_read_next_header(a, &ae));
+	assertEqualInt(ARCHIVE_OK, archive_read_close(a));
+	assertEqualInt(ARCHIVE_OK, archive_read_free(a));
+}
+
 
 DEFINE_TEST(test_compat_zip)
 {
 	test_compat_zip_1();
+	test_compat_zip_2();
 }
 
 
diff --git a/lib/libarchive/test/test_compat_zip_2.zip.uu b/lib/libarchive/test/test_compat_zip_2.zip.uu
new file mode 100644
index 0000000..c33e9d9
--- /dev/null
+++ b/lib/libarchive/test/test_compat_zip_2.zip.uu
@@ -0,0 +1,10 @@
+$FreeBSD$
+
+begin 644 test_compat_zip_2.zip
+M4$L#!`H``````'V59CT````````````````%````9FEL93$M2E5.2RU02P,$
+M"@``````@95F/<>D!,D&````!@````4```!F:6QE,F9I;&4R"E!+`0(>`PH`
+M`````'V59CT````````````````%``````````````"D@0````!F:6QE,5!+
+M`0(>`PH``````(&59CW'I`3)!@````8````%``````````````"D@2D```!F
+::6QE,E!+!08``````@`"`&8```!2````````
+`
+end