diff options
Diffstat (limited to 'checksum.c')
| -rw-r--r-- | checksum.c | 39 |
1 files changed, 2 insertions, 37 deletions
@@ -17,16 +17,13 @@ * Original code by Hannes Gredler (hannes@gredler.at) */ -#ifdef HAVE_CONFIG_H #include <config.h> -#endif #include "netdissect-stdinc.h" #include <stdio.h> #include <stdlib.h> #include <string.h> -#include <assert.h> #include "netdissect.h" @@ -44,7 +41,7 @@ for i in range(256): accum ^= 0x633 crc_table.append(accum) -for i in range(len(crc_table)/8): +for i in range(int(len(crc_table)/8)): for j in range(8): sys.stdout.write("0x%04x, " % crc_table[i*8+j]) sys.stdout.write("\n") @@ -86,36 +83,12 @@ static const uint16_t crc10_table[256] = 0x021e, 0x002d, 0x004b, 0x0278, 0x0087, 0x02b4, 0x02d2, 0x00e1 }; -static void -init_crc10_table(void) -{ -#define CRC10_POLYNOMIAL 0x633 - int i, j; - uint16_t accum; - uint16_t verify_crc10_table[256]; - - for ( i = 0; i < 256; i++ ) - { - accum = ((unsigned short) i << 2); - for ( j = 0; j < 8; j++ ) - { - if ((accum <<= 1) & 0x400) accum ^= CRC10_POLYNOMIAL; - } - verify_crc10_table[i] = accum; - } - assert(memcmp(verify_crc10_table, - crc10_table, - sizeof(verify_crc10_table)) == 0); -#undef CRC10_POLYNOMIAL -} - uint16_t verify_crc10_cksum(uint16_t accum, const u_char *p, int length) { int i; - for ( i = 0; i < length; i++ ) - { + for ( i = 0; i < length; i++ ) { accum = ((accum << 8) & 0x3ff) ^ crc10_table[( accum >> 2) & 0xff] ^ *p++; @@ -123,14 +96,6 @@ verify_crc10_cksum(uint16_t accum, const u_char *p, int length) return accum; } -/* precompute checksum tables */ -void -init_checksum(void) { - - init_crc10_table(); - -} - /* * Creates the OSI Fletcher checksum. See 8473-1, Appendix C, section C.3. * The checksum field of the passed PDU does not need to be reset to zero. |