diff options
author | Guy Harris <guy@alum.mit.edu> | 2014-08-08 12:51:32 -0700 |
---|---|---|
committer | Guy Harris <guy@alum.mit.edu> | 2014-08-08 19:52:08 +0000 |
commit | 479e2881f85d835982292d3b4a5dd9c144eecc7a (patch) | |
tree | 67b741235bbb92dbe85d7173994a94ba2e84e940 | |
parent | cf5f0d3827f761325059996b879a5876f8513926 (diff) |
The "MPEG-2" CRC-32 is also the ATM CRC-32.
Use it in the ATM dissector, and use a tvbuff version, so that we don't
do tvb_get_ptr() ourselves.
Change-Id: I0bd3594bc739e0cca447ac06f34a471441cf2e70
Reviewed-on: https://code.wireshark.org/review/3513
Reviewed-by: Guy Harris <guy@alum.mit.edu>
-rw-r--r-- | epan/dissectors/packet-atm.c | 128 | ||||
-rw-r--r-- | wsutil/crc32.c | 2 |
2 files changed, 4 insertions, 126 deletions
diff --git a/epan/dissectors/packet-atm.c b/epan/dissectors/packet-atm.c index c8cec768bc..3e2de94def 100644 --- a/epan/dissectors/packet-atm.c +++ b/epan/dissectors/packet-atm.c @@ -30,6 +30,7 @@ #include <epan/ppptypes.h> #include <epan/expert.h> #include <epan/crc10-tvb.h> +#include <epan/crc32-tvb.h> #include "packet-atm.h" #include "packet-snmp.h" @@ -827,130 +828,6 @@ capture_atm(const union wtap_pseudo_header *pseudo_header, const guchar *pd, ld->other++; } -/* - * Charles Michael Heard's CRC-32 code, from - * - * http://www.cell-relay.com/cell-relay/publications/software/CRC/32bitCRC.c.html - * - * with the CRC table initialized with values computed by - * his "gen_crc_table()" routine, rather than by calling that routine - * at run time, and with various data type cleanups. - */ - -/* crc32h.c -- package to compute 32-bit CRC one byte at a time using */ -/* the high-bit first (Big-Endian) bit ordering convention */ -/* */ -/* Synopsis: */ -/* gen_crc_table() -- generates a 256-word table containing all CRC */ -/* remainders for every possible 8-bit byte. It */ -/* must be executed (once) before any CRC updates. */ -/* */ -/* unsigned update_crc(crc_accum, data_blk_ptr, data_blk_size) */ -/* unsigned crc_accum; char *data_blk_ptr; int data_blk_size; */ -/* Returns the updated value of the CRC accumulator after */ -/* processing each byte in the addressed block of data. */ -/* */ -/* It is assumed that an unsigned long is at least 32 bits wide and */ -/* that the predefined type char occupies one 8-bit byte of storage. */ -/* */ -/* The generator polynomial used for this version of the package is */ -/* x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x^1+x^0 */ -/* as specified in the Autodin/Ethernet/ADCCP protocol standards. */ -/* Other degree 32 polynomials may be substituted by re-defining the */ -/* symbol POLYNOMIAL below. Lower degree polynomials must first be */ -/* multiplied by an appropriate power of x. The representation used */ -/* is that the coefficient of x^0 is stored in the LSB of the 32-bit */ -/* word and the coefficient of x^31 is stored in the most significant */ -/* bit. The CRC is to be appended to the data most significant byte */ -/* first. For those protocols in which bytes are transmitted MSB */ -/* first and in the same order as they are encountered in the block */ -/* this convention results in the CRC remainder being transmitted with */ -/* the coefficient of x^31 first and with that of x^0 last (just as */ -/* would be done by a hardware shift register mechanization). */ -/* */ -/* The table lookup technique was adapted from the algorithm described */ -/* by Avram Perez, Byte-wise CRC Calculations, IEEE Micro 3, 40 (1983).*/ - -static const guint32 crc_table[256] = { - 0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, - 0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005, - 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61, - 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, - 0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9, - 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75, - 0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, - 0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd, - 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039, - 0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, - 0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81, - 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d, - 0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, - 0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95, - 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, - 0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, - 0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae, - 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072, - 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, - 0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca, - 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde, - 0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, - 0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066, - 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba, - 0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, - 0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692, - 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6, - 0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, - 0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e, - 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2, - 0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, - 0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a, - 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637, - 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, - 0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f, - 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53, - 0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, - 0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b, - 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff, - 0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, - 0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7, - 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b, - 0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, - 0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3, - 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7, - 0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, - 0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f, - 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3, - 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, - 0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c, - 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8, - 0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, - 0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30, - 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec, - 0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, - 0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654, - 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0, - 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, - 0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18, - 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4, - 0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, - 0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c, - 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668, - 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4, -}; - -static guint32 -update_crc(guint32 crc_accum, const guint8 *data_blk_ptr, int data_blk_size) -{ - register int i, j; - - /* update the CRC on the data block one byte at a time */ - for (j = 0; j < data_blk_size; j++) { - i = ( (int) ( crc_accum >> 24) ^ *data_blk_ptr++ ) & 0xff; - crc_accum = ( crc_accum << 8 ) ^ crc_table[i]; - } - return crc_accum; -} - static void dissect_reassembled_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, proto_item *atm_ti, @@ -1090,8 +967,7 @@ dissect_reassembled_pdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, proto_tree_add_item(atm_tree, hf_atm_aal5_len, tvb, length - 6, 2, ENC_BIG_ENDIAN); crc = tvb_get_ntohl(tvb, length - 4); - calc_crc = update_crc(0xFFFFFFFF, tvb_get_ptr(tvb, 0, length), - length); + calc_crc = crc32_mpeg2_tvb(tvb, length); ti = proto_tree_add_uint(atm_tree, hf_atm_aal5_crc, tvb, length - 4, 4, crc); proto_item_append_text(ti, (calc_crc == 0xC704DD7B) ? " (correct)" : " (incorrect)"); } diff --git a/wsutil/crc32.c b/wsutil/crc32.c index 549705c125..142a457f44 100644 --- a/wsutil/crc32.c +++ b/wsutil/crc32.c @@ -179,6 +179,8 @@ static const guint32 crc32_ccitt_table[256] = { * x^7 + x^5 + x^4 + x^2 + x + 1 * * (which is the same polynomial as the one above us). + * + * NOTE: this is also used for ATM AAL5. */ static const guint32 crc32_mpeg2_table[256] = { 0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b, |