Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 167 insertions, 0 deletions

diff --git a/epan/tvbuff_lznt1.c b/epan/tvbuff_lznt1.c
new file mode 100644
index 00000000..9afb8d74
--- /dev/null
+++ b/epan/tvbuff_lznt1.c
@@ -0,0 +1,167 @@
+/*
+ * Decompression code for LZNT1. This encoding is used by
+ * Microsoft in various file formats and protocols including SMB3.
+ *
+ * See MS-XCA.
+ *
+ * Copyright (C) 2019  Aurélien Aptel
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include <glib.h>
+#include <epan/exceptions.h>
+#include <epan/tvbuff.h>
+#include <epan/wmem_scopes.h>
+
+#define MAX_INPUT_SIZE (16*1024*1024) /* 16MB */
+
+static gboolean
+uncompress_chunk(tvbuff_t *tvb, int offset, int in_size, wmem_array_t *obuf)
+{
+	int in_off = 0, out_off = 0, out_start = 0;
+	guint8 flags;
+	guint i, j, val, pos;
+
+	out_start = wmem_array_get_count(obuf);
+
+	while (in_off < in_size) {
+		flags = tvb_get_guint8(tvb, offset+in_off);
+		in_off++;
+		for (i = 0; i < 8; i++) {
+			if (0 == ((flags>>i)&1)) {
+				val = tvb_get_guint8(tvb, offset+in_off);
+				in_off++;
+				wmem_array_append_one(obuf, val);
+				out_off++;
+			} else {
+				guint f, l_mask = 0x0FFF, o_shift = 12;
+				guint match_len, match_off;
+
+				f = tvb_get_letohs(tvb, offset+in_off);
+				in_off += 2;
+				pos = out_off-1;
+				while (pos >= 0x10) {
+					l_mask >>= 1;
+					o_shift -= 1;
+					pos >>= 1;
+				}
+
+				match_len = (f & l_mask) + 3;
+				match_off = (f >> o_shift) + 1;
+				for (j = 0; j < match_len; j++) {
+					guint8 byte;
+					if (match_off > (guint)out_off)
+						return FALSE;
+					if (wmem_array_try_index(obuf, out_start+out_off-match_off, &byte))
+						return FALSE;
+					wmem_array_append_one(obuf, byte);
+					out_off++;
+				}
+			}
+			if (in_off == in_size) {
+				goto out;
+			}
+		}
+	}
+out:
+	return TRUE;
+}
+
+static gboolean
+do_uncompress(tvbuff_t *tvb, int offset, int in_size, wmem_array_t *obuf)
+{
+	int in_off = 0;
+	guint32 header, length, i;
+	gboolean ok;
+
+	if (!tvb)
+		return FALSE;
+
+	if (!in_size || in_size > MAX_INPUT_SIZE)
+		return FALSE;
+
+	while (in_off < in_size) {
+		header = tvb_get_letohs(tvb, offset+in_off);
+		in_off += 2;
+		length = (header & 0x0FFF) + 1;
+		if (!(header & 0x8000)) {
+			for (i = 0; i < length; i++) {
+				guint8 v = tvb_get_guint8(tvb, offset+in_off);
+				wmem_array_append_one(obuf, v);
+				in_off++;
+			}
+		} else {
+			ok = uncompress_chunk(tvb, offset + in_off, length, obuf);
+			if (!ok)
+				return FALSE;
+			in_off += length;
+		}
+	}
+	return TRUE;
+}
+
+tvbuff_t *
+tvb_uncompress_lznt1(tvbuff_t *tvb, const int offset, int in_size)
+{
+	volatile gboolean ok = FALSE;
+	wmem_allocator_t *pool;
+	wmem_array_t *obuf;
+	tvbuff_t *out;
+
+	pool = wmem_allocator_new(WMEM_ALLOCATOR_SIMPLE);
+	obuf = wmem_array_sized_new(pool, 1, in_size*2);
+
+	TRY {
+                ok = do_uncompress(tvb, offset, in_size, obuf);
+	} CATCH_ALL {
+		ok = FALSE;
+	}
+	ENDTRY;
+
+	if (ok) {
+		/*
+		 * Cannot pass a tvb free callback that frees the wmem
+		 * pool, so we make an extra copy that uses bare
+		 * pointers. This could be optimized if tvb API had a
+		 * free pool callback of some sort.
+		 */
+		guint size = wmem_array_get_count(obuf);
+		guint8 *p = (guint8 *)g_malloc(size);
+		memcpy(p, wmem_array_get_raw(obuf), size);
+		out = tvb_new_real_data(p, size, size);
+		tvb_set_free_cb(out, g_free);
+	} else {
+		out = NULL;
+	}
+
+	wmem_destroy_allocator(pool);
+
+	return out;
+}
+
+tvbuff_t *
+tvb_child_uncompress_lznt1(tvbuff_t *parent, tvbuff_t *tvb, const int offset, int in_size)
+{
+	tvbuff_t *new_tvb = tvb_uncompress_lznt1(tvb, offset, in_size);
+	if (new_tvb)
+		tvb_set_child_real_data_tvbuff(parent, new_tvb);
+	return new_tvb;
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local variables:
+ * c-basic-offset: 8
+ * tab-width: 8
+ * indent-tabs-mode: t
+ * End:
+ *
+ * vi: set shiftwidth=8 tabstop=8 noexpandtab:
+ * :indentSize=8:tabSize=8:noTabs=false:
+ */