Adding upstream version 4.2.2.upstream/4.2.2

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

1 files changed, 95 insertions, 0 deletions

diff --git a/epan/addr_and_mask.c b/epan/addr_and_mask.c
new file mode 100644
index 00000000..b776d85a
--- /dev/null
+++ b/epan/addr_and_mask.c
@@ -0,0 +1,95 @@
+/* addr_and_mask.c
+ * Routines to fetch IPv4 and IPv6 addresses from a tvbuff and then mask
+ * out bits other than those covered by a prefix length
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald@wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "tvbuff.h"
+#include "ipv6.h"
+#include "addr_and_mask.h"
+#include <wsutil/ws_assert.h>
+
+guint32
+ip_get_subnet_mask(const guint32 mask_length)
+{
+	static const guint32 masks[33] = {
+		0x00000000,
+		0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
+		0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
+		0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
+		0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
+		0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
+		0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
+		0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
+		0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff,
+	};
+
+	ws_assert(mask_length <= 32);
+
+	return masks[mask_length];
+}
+
+/*
+ * These routines return the length of the address in bytes on success
+ * and -1 if the prefix length is too long.
+ */
+
+int
+tvb_get_ipv4_addr_with_prefix_len(tvbuff_t *tvb, int offset, ws_in4_addr *addr,
+    guint32 prefix_len)
+{
+	guint8 addr_len;
+
+	if (prefix_len > 32)
+		return -1;
+
+	addr_len = (prefix_len + 7) / 8;
+	*addr = 0;
+	tvb_memcpy(tvb, addr, offset, addr_len);
+	if (prefix_len % 8)
+		((guint8*)addr)[addr_len - 1] &= ((0xff00 >> (prefix_len % 8)) & 0xff);
+	return addr_len;
+}
+
+int
+tvb_get_ipv6_addr_with_prefix_len(tvbuff_t *tvb, int offset, ws_in6_addr *addr,
+    guint32 prefix_len)
+{
+	guint32 addr_len;
+
+	if (prefix_len > 128)
+		return -1;
+
+	addr_len = (prefix_len + 7) / 8;
+	memset(addr->bytes, 0, 16);
+	tvb_memcpy(tvb, addr->bytes, offset, addr_len);
+	if (prefix_len % 8) {
+		addr->bytes[addr_len - 1] &=
+		    ((0xff00 >> (prefix_len % 8)) & 0xff);
+	}
+
+	return addr_len;
+}
+
+/*
+ * 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:
+ */