diff options
Diffstat (limited to 'third_party/heimdal/lib/krb5/crc.c')
-rw-r--r-- | third_party/heimdal/lib/krb5/crc.c | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/krb5/crc.c b/third_party/heimdal/lib/krb5/crc.c new file mode 100644 index 0000000..3090760 --- /dev/null +++ b/third_party/heimdal/lib/krb5/crc.c @@ -0,0 +1,69 @@ +/* + * Copyright (c) 1997 - 2000 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "krb5_locl.h" + +static u_long table[256]; + +#define CRC_GEN 0xEDB88320L + +KRB5_LIB_FUNCTION void KRB5_LIB_CALL +_krb5_crc_init_table(void) +{ + static int flag = 0; + unsigned long crc, poly; + unsigned int i, j; + + if(flag) return; + poly = CRC_GEN; + for (i = 0; i < 256; i++) { + crc = i; + for (j = 8; j > 0; j--) { + if (crc & 1) { + crc = (crc >> 1) ^ poly; + } else { + crc >>= 1; + } + } + table[i] = crc; + } + flag = 1; +} + +KRB5_LIB_FUNCTION uint32_t KRB5_LIB_CALL +_krb5_crc_update (const char *p, size_t len, uint32_t res) +{ + while (len--) + res = table[(res ^ *p++) & 0xFF] ^ (res >> 8); + return res & 0xFFFFFFFF; +} |