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-rw-r--r--third_party/heimdal/lib/krb5/crc.c69
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
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+++ b/third_party/heimdal/lib/krb5/crc.c
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+/*
+ * 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;
+}