add functions to calculate the CRC of an ISO14443-A message

Change-Id: I1ccd9885746a6044f298d7d531a9bc009a70288e
Reviewed-on: https://code.wireshark.org/review/13802
Petri-Dish: Martin Kaiser <wireshark@kaiser.cx>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/epan/crc16-tvb.c b/epan/crc16-tvb.c
index b20d759c50..bea77bdff2 100644
--- a/epan/crc16-tvb.c
+++ b/epan/crc16-tvb.c
@@ -98,6 +98,16 @@ guint16 crc16_ccitt_tvb_offset_seed(tvbuff_t *tvb, guint offset, guint len, guin
     return crc16_ccitt_seed(buf, len, seed);
 }
 
+guint16 crc16_iso14443a_tvb_offset(tvbuff_t *tvb, guint offset, guint len)
+{
+    const guint8 *buf;
+
+    tvb_ensure_bytes_exist(tvb, offset, len);  /* len == -1 not allowed */
+    buf = tvb_get_ptr(tvb, offset, len);
+
+    return crc16_iso14443a(buf, len);
+}
+
 guint16 crc16_plain_tvb_offset(tvbuff_t *tvb, guint offset, guint len)
 {
     guint16 crc = crc16_plain_init();