/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* lib/crypto/crc32/crc.c
*
* Copyright 1990, 2002 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* CRC-32/AUTODIN-II routines
*/
#include <k5-int.h>
#include <crc-32.h>
/* This table and block of comments are taken from code labeled: */
/*
* Copyright (C) 1986 Gary S. Brown. You may use this program, or
* code or tables extracted from it, as desired without restriction.
*/
/* First, the polynomial itself and its table of feedback terms. The */
/* polynomial 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 */
/* Note that we take it "backwards" and put the highest-order term in */
/* the lowest-order bit. The X^32 term is "implied"; the LSB is the */
/* X^31 term, etc. The X^0 term (usually shown as "+1") results in */
/* the MSB being 1. */
/* Note that the usual hardware shift register implementation, which */
/* is what we're using (we're merely optimizing it by doing eight-bit */
/* chunks at a time) shifts bits into the lowest-order term. In our */
/* implementation, that means shifting towards the right. Why do we */
/* do it this way? Because the calculated CRC must be transmitted in */
/* order from highest-order term to lowest-order term. UARTs transmit */
/* characters in order from LSB to MSB. By storing the CRC this way, */
/* we hand it to the UART in the order low-byte to high-byte; the UART */
/* sends each low-bit to hight-bit; and the result is transmission bit */
/* by bit from highest- to lowest-order term without requiring any bit */
/* shuffling on our part. Reception works similarly. */
/* The feedback terms table consists of 256, 32-bit entries. Notes: */
/* */
/* 1. The table can be generated at runtime if desired; code to do so */
/* is shown later. It might not be obvious, but the feedback */
/* terms simply represent the results of eight shift/xor opera- */
/* tions for all combinations of data and CRC register values. */
/* */
/* 2. The CRC accumulation logic is the same for all CRC polynomials, */
/* be they sixteen or thirty-two bits wide. You simply choose the */
/* appropriate table. Alternatively, because the table can be */
/* generated at runtime, you can start by generating the table for */
/* the polynomial in question and use exactly the same "updcrc", */
/* if your application needn't simultaneously handle two CRC */
/* polynomials. (Note, however, that XMODEM is strange.) */
/* */
/* 3. For 16-bit CRCs, the table entries need be only 16 bits wide; */
/* of course, 32-bit entries work OK if the high 16 bits are zero. */
/* */
/* 4. The values must be right-shifted by eight bits by the "updcrc" */
/* logic; the shift must be unsigned (bring in zeroes). On some */
/* hardware you could probably optimize the shift in assembler by */
/* using byte-swap instructions. */
static uint32_t const crc_table[256] = {
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};
/* Windows needs to these prototypes for crc32_cksumtable_entry below */
static krb5_error_code
crc32_sum_func (
krb5_const krb5_pointer in,
krb5_const size_t in_length,
krb5_const krb5_pointer seed,
krb5_const size_t seed_length,
krb5_checksum *outcksum);
static krb5_error_code
crc32_verify_func (
krb5_const krb5_checksum *cksum,
krb5_const krb5_pointer in,
krb5_const size_t in_length,
krb5_const krb5_pointer seed,
krb5_const size_t seed_length);
/*ARGSUSED*/
static krb5_error_code
crc32_sum_func(in, in_length, seed, seed_length, outcksum)
krb5_const krb5_pointer in;
krb5_const size_t in_length;
krb5_const krb5_pointer seed;
krb5_const size_t seed_length;
krb5_checksum *outcksum;
{
register u_char *data;
register u_long c = 0;
register int idx;
size_t i;
if (outcksum->length < CRC32_CKSUM_LENGTH)
return KRB5_BAD_MSIZE;
data = (u_char *)in;
for (i = 0; i < in_length; i++) {
idx = (int) (data[i] ^ c);
idx &= 0xff;
c >>= 8;
c ^= (u_long) crc_table[idx];
}
/* c now holds the result */
outcksum->checksum_type = CKSUMTYPE_CRC32;
outcksum->length = CRC32_CKSUM_LENGTH;
outcksum->contents[0] = (krb5_octet) (c & 0xff);
outcksum->contents[1] = (krb5_octet) ((c >> 8) & 0xff);
outcksum->contents[2] = (krb5_octet) ((c >> 16) & 0xff);
outcksum->contents[3] = (krb5_octet) ((c >> 24) & 0xff);
return 0;
}
/*ARGSUSED*/
static krb5_error_code
crc32_verify_func(cksum, in, in_length, seed, seed_length)
krb5_const krb5_checksum *cksum;
krb5_const krb5_pointer in;
krb5_const size_t in_length;
krb5_const krb5_pointer seed;
krb5_const size_t seed_length;
{
register u_char *data;
register u_long c = 0;
register int idx;
size_t i;
krb5_error_code retval;
retval = 0;
if (cksum->checksum_type == CKSUMTYPE_CRC32) {
if (cksum->length == CRC32_CKSUM_LENGTH) {
data = (u_char *)in;
for (i = 0; i < in_length; i++) {
idx = (int) (data[i] ^ c);
idx &= 0xff;
c >>= 8;
c ^= (u_long) crc_table[idx];
}
if ((cksum->contents[0] != (krb5_octet) (c & 0xff)) ||
(cksum->contents[1] != (krb5_octet) ((c >> 8) & 0xff)) ||
(cksum->contents[2] != (krb5_octet) ((c >> 16) & 0xff)) ||
(cksum->contents[3] != (krb5_octet) ((c >> 24) & 0xff)))
retval = KRB5KRB_AP_ERR_BAD_INTEGRITY;
}
else
retval = KRB5KRB_AP_ERR_BAD_INTEGRITY;
}
else
retval = KRB5KRB_AP_ERR_INAPP_CKSUM;
return(retval);
}