diff options
| -rw-r--r-- | epan/crc8-tvb.c | 13 | ||||
| -rw-r--r-- | epan/crc8-tvb.h | 5 |
2 files changed, 16 insertions, 2 deletions
diff --git a/epan/crc8-tvb.c b/epan/crc8-tvb.c index da5affd530..8e7497b4df 100644 --- a/epan/crc8-tvb.c +++ b/epan/crc8-tvb.c @@ -61,7 +61,7 @@ static const guint8 crctable[256] = { /*reversed, 8-bit, poly=0x07*/ gboolean check_fcs(tvbuff_t *p, guint8 len, guint8 offset, guint8 received_fcs){ /*Init*/ - guint8 FCS=0xFF; + guint8 FCS = 0xFF; guint8 tmp = 0; /*len is the number of bytes in the message, p points to message*/ while (len--) { @@ -82,4 +82,15 @@ gboolean check_fcs(tvbuff_t *p, guint8 len, guint8 offset, guint8 received_fcs){ } } +guint8 get_crc8_ieee8023_epon(tvbuff_t *p, guint8 len, guint8 offset) { + guint8 FCS = 0x00; + guint8 tmp = 0; + while (len--) { + tmp = FCS^tvb_get_guint8(p,offset); + offset++; + FCS=crctable[tmp]; + } + + return FCS; +} diff --git a/epan/crc8-tvb.h b/epan/crc8-tvb.h index 667a1b4354..1d0a632b99 100644 --- a/epan/crc8-tvb.h +++ b/epan/crc8-tvb.h @@ -8,7 +8,9 @@ * Polynom: (x^8 + x^2 + x^1 + 1) * * 2011 Hans-Christoph Schemmel <hans-christoph.schemmel[AT]cinterion.com> - * + * 2014 Philip Rosenberg-Watt <p.rosenberg-watt[at]cablelabs.com> + * + Added CRC-8 for IEEE 802.3 EPON, with shift register initialized to 0x00 + * See IEEE Std 802.3-2012 Section 5, Clause 65.1.3.2.3. * * Wireshark - Network traffic analyzer * By Gerald Combs <gerald@wireshark.org> @@ -44,5 +46,6 @@ #define __CRC8_TVB_H__ extern gboolean check_fcs(tvbuff_t *p, guint8 len, guint8 offset, guint8 received_fcs); +extern guint8 get_crc8_ieee8023_epon(tvbuff_t *p, guint8 len, guint8 offset); #endif /* __CRC8_TVB_H__ */ |