diff options
author | lego <lego@f5534014-38df-0310-8fa8-9805f1628bb7> | 2007-07-17 22:04:00 +0000 |
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committer | lego <lego@f5534014-38df-0310-8fa8-9805f1628bb7> | 2007-07-17 22:04:00 +0000 |
commit | e0eefb1aadd495e66e948924d1c7918b19063370 (patch) | |
tree | 73e6e2dd8162c4d81b3c835af3b82c6162050be1 /epan/dissectors/packet-iuup.c | |
parent | 32af7c83b8398bab6839567b5595bca60bd72fd1 (diff) |
get crc10 and crc6 out of packet-iuup.c
- experimental code for a way-too-heurstic look for iuup dissector
git-svn-id: http://anonsvn.wireshark.org/wireshark/trunk@22341 f5534014-38df-0310-8fa8-9805f1628bb7
Diffstat (limited to 'epan/dissectors/packet-iuup.c')
-rw-r--r-- | epan/dissectors/packet-iuup.c | 144 |
1 files changed, 52 insertions, 92 deletions
diff --git a/epan/dissectors/packet-iuup.c b/epan/dissectors/packet-iuup.c index d11e821b8d..480cace056 100644 --- a/epan/dissectors/packet-iuup.c +++ b/epan/dissectors/packet-iuup.c @@ -43,6 +43,8 @@ #include <epan/prefs.h> #include <epan/emem.h> #include <epan/expert.h> +#include <epan/crc10.h> +#include <epan/crc6.h> typedef struct _iuup_rfci_t { @@ -320,95 +322,6 @@ static const value_string iuup_fqcs[] = { {3, "spare"}, {0,NULL} }; -/* - * Charles Michael Heard's CRC-10 code, from - * - * http://cell-relay.indiana.edu/cell-relay/publications/software/CRC/crc10.html - * - * with the CRC table initialized with values computed by - * his "gen_byte_crc10_table()" routine, rather than by calling that - * routine at run time, and with various data type cleanups. - */ -static const guint16 byte_crc10_table[256] = { - 0x0000, 0x0233, 0x0255, 0x0066, 0x0299, 0x00aa, 0x00cc, 0x02ff, - 0x0301, 0x0132, 0x0154, 0x0367, 0x0198, 0x03ab, 0x03cd, 0x01fe, - 0x0031, 0x0202, 0x0264, 0x0057, 0x02a8, 0x009b, 0x00fd, 0x02ce, - 0x0330, 0x0103, 0x0165, 0x0356, 0x01a9, 0x039a, 0x03fc, 0x01cf, - 0x0062, 0x0251, 0x0237, 0x0004, 0x02fb, 0x00c8, 0x00ae, 0x029d, - 0x0363, 0x0150, 0x0136, 0x0305, 0x01fa, 0x03c9, 0x03af, 0x019c, - 0x0053, 0x0260, 0x0206, 0x0035, 0x02ca, 0x00f9, 0x009f, 0x02ac, - 0x0352, 0x0161, 0x0107, 0x0334, 0x01cb, 0x03f8, 0x039e, 0x01ad, - 0x00c4, 0x02f7, 0x0291, 0x00a2, 0x025d, 0x006e, 0x0008, 0x023b, - 0x03c5, 0x01f6, 0x0190, 0x03a3, 0x015c, 0x036f, 0x0309, 0x013a, - 0x00f5, 0x02c6, 0x02a0, 0x0093, 0x026c, 0x005f, 0x0039, 0x020a, - 0x03f4, 0x01c7, 0x01a1, 0x0392, 0x016d, 0x035e, 0x0338, 0x010b, - 0x00a6, 0x0295, 0x02f3, 0x00c0, 0x023f, 0x000c, 0x006a, 0x0259, - 0x03a7, 0x0194, 0x01f2, 0x03c1, 0x013e, 0x030d, 0x036b, 0x0158, - 0x0097, 0x02a4, 0x02c2, 0x00f1, 0x020e, 0x003d, 0x005b, 0x0268, - 0x0396, 0x01a5, 0x01c3, 0x03f0, 0x010f, 0x033c, 0x035a, 0x0169, - 0x0188, 0x03bb, 0x03dd, 0x01ee, 0x0311, 0x0122, 0x0144, 0x0377, - 0x0289, 0x00ba, 0x00dc, 0x02ef, 0x0010, 0x0223, 0x0245, 0x0076, - 0x01b9, 0x038a, 0x03ec, 0x01df, 0x0320, 0x0113, 0x0175, 0x0346, - 0x02b8, 0x008b, 0x00ed, 0x02de, 0x0021, 0x0212, 0x0274, 0x0047, - 0x01ea, 0x03d9, 0x03bf, 0x018c, 0x0373, 0x0140, 0x0126, 0x0315, - 0x02eb, 0x00d8, 0x00be, 0x028d, 0x0072, 0x0241, 0x0227, 0x0014, - 0x01db, 0x03e8, 0x038e, 0x01bd, 0x0342, 0x0171, 0x0117, 0x0324, - 0x02da, 0x00e9, 0x008f, 0x02bc, 0x0043, 0x0270, 0x0216, 0x0025, - 0x014c, 0x037f, 0x0319, 0x012a, 0x03d5, 0x01e6, 0x0180, 0x03b3, - 0x024d, 0x007e, 0x0018, 0x022b, 0x00d4, 0x02e7, 0x0281, 0x00b2, - 0x017d, 0x034e, 0x0328, 0x011b, 0x03e4, 0x01d7, 0x01b1, 0x0382, - 0x027c, 0x004f, 0x0029, 0x021a, 0x00e5, 0x02d6, 0x02b0, 0x0083, - 0x012e, 0x031d, 0x037b, 0x0148, 0x03b7, 0x0184, 0x01e2, 0x03d1, - 0x022f, 0x001c, 0x007a, 0x0249, 0x00b6, 0x0285, 0x02e3, 0x00d0, - 0x011f, 0x032c, 0x034a, 0x0179, 0x0386, 0x01b5, 0x01d3, 0x03e0, - 0x021e, 0x002d, 0x004b, 0x0278, 0x0087, 0x02b4, 0x02d2, 0x00e1 -}; - -/* update the data block's CRC-10 remainder one byte at a time */ -static guint16 -update_crc10_by_bytes(guint16 crc10, const guint8 *data_blk_ptr, - int data_blk_size) -{ - register int i; - guint16 crc10_accum = 0; - - for (i = 0; i < data_blk_size; i++) { - crc10_accum = ((crc10_accum << 8) & 0x3ff) - ^ byte_crc10_table[( crc10_accum >> 2) & 0xff] - ^ *data_blk_ptr++; - } - crc10_accum = ((crc10_accum << 8) & 0x3ff) - ^ byte_crc10_table[( crc10_accum >> 2) & 0xff] - ^ (crc10>>2); - crc10_accum = ((crc10_accum << 8) & 0x3ff) - ^ byte_crc10_table[( crc10_accum >> 2) & 0xff] - ^ ((crc10<<6) & 0xFF); - - return crc10_accum; -} - - -static guint16 -update_crc6_by_bytes(guint16 crc6, unsigned char byte1, unsigned char byte2) -{ - char bit; - unsigned int remainder = 0; - unsigned int polynomial = 0x6F << 15; - - unsigned int data = ( byte1<<8 | byte2 ) << 6; - remainder = data; - - for (bit = 15; bit >= 0; --bit) - { - if (remainder & (0x40 << bit)) - { - remainder ^= polynomial; - } - polynomial >>= 1; - } - - return (remainder ^ crc6); -} static proto_item* @@ -885,7 +798,54 @@ static void dissect_iuup(tvbuff_t* tvb_in, packet_info* pinfo, proto_tree* tree) if (!tree) return; proto_item_set_expert_flags(pdutype_item, PI_MALFORMED, PI_ERROR); return; - }; + } +} + + +static gboolean dissect_iuup_heur(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { + int len = tvb_length_remaining(tvb,0); + + guint8 first_octet = tvb_get_guint8(tvb,0); + guint8 second_octet = tvb_get_guint8(tvb,1); + guint16 hdrcrc6 = tvb_get_guint8(tvb, 2) >> 2; + + if (update_crc6_by_bytes(hdrcrc6, first_octet, second_octet)) return FALSE; + + switch ( first_octet & 0xf0 ) { + case 0x00: { + if (len<7) return FALSE; + if (update_crc10_by_bytes(tvb_get_ntohs(tvb, 4) & 0x3FF, tvb_get_ptr(tvb, 6, len-4), len-4) ) return FALSE; + break; + } + case 0x10: + /* a FALSE positive factory */ + if (len<5) return FALSE; + break; + case 0xe0: + if (len<5) return FALSE; + if( (second_octet & 0x0f) > 3) return FALSE; + default: + return FALSE; + } + + dissect_iuup(tvb, pinfo, tree); + return TRUE; +} + + +static void find_iuup(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { + int len = tvb_length_remaining(tvb,0); + int offset = 0; + + while (len > 3) { + if ( dissect_iuup_heur(tvb_new_subset(tvb,offset,-1,-1), pinfo, tree) ) + return; + + offset++; + len--; + } + + call_dissector(data_handle, tvb, pinfo, tree); } static void init_iuup(void) { @@ -1030,6 +990,8 @@ void proto_register_iuup(void) { proto_register_field_array(proto_iuup, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_dissector("iuup", dissect_iuup, proto_iuup); + register_dissector("find_iuup", find_iuup, proto_iuup); + register_init_routine(&init_iuup); iuup_handle = create_dissector_handle(dissect_iuup, proto_iuup); @@ -1051,7 +1013,5 @@ void proto_register_iuup(void) { "The dynamic payload type which will be interpreted as IuUP", 10, &temp_dynamic_payload_type); - - } |