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-rw-r--r--libraries/liblutil/hash.c77
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diff --git a/libraries/liblutil/hash.c b/libraries/liblutil/hash.c
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+/* $OpenLDAP$ */
+/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
+ *
+ * Copyright 2000-2021 The OpenLDAP Foundation.
+ * Portions Copyright 2000-2003 Kurt D. Zeilenga.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted only as authorized by the OpenLDAP
+ * Public License.
+ *
+ * A copy of this license is available in the file LICENSE in the
+ * top-level directory of the distribution or, alternatively, at
+ * <http://www.OpenLDAP.org/license.html>.
+ */
+
+/* This implements the Fowler / Noll / Vo (FNV-1) hash algorithm.
+ * A summary of the algorithm can be found at:
+ * http://www.isthe.com/chongo/tech/comp/fnv/index.html
+ */
+
+#include "portable.h"
+
+#include <lutil_hash.h>
+
+/* offset and prime for 32-bit FNV-1 */
+#define HASH_OFFSET 0x811c9dc5U
+#define HASH_PRIME 16777619
+
+
+/*
+ * Initialize context
+ */
+void
+lutil_HASHInit( struct lutil_HASHContext *ctx )
+{
+ ctx->hash = HASH_OFFSET;
+}
+
+/*
+ * Update hash
+ */
+void
+lutil_HASHUpdate(
+ struct lutil_HASHContext *ctx,
+ const unsigned char *buf,
+ ber_len_t len )
+{
+ const unsigned char *p, *e;
+ ber_uint_t h;
+
+ p = buf;
+ e = &buf[len];
+
+ h = ctx->hash;
+
+ while( p < e ) {
+ h *= HASH_PRIME;
+ h ^= *p++;
+ }
+
+ ctx->hash = h;
+}
+
+/*
+ * Save hash
+ */
+void
+lutil_HASHFinal( unsigned char *digest, struct lutil_HASHContext *ctx )
+{
+ ber_uint_t h = ctx->hash;
+
+ digest[0] = h & 0xffU;
+ digest[1] = (h>>8) & 0xffU;
+ digest[2] = (h>>16) & 0xffU;
+ digest[3] = (h>>24) & 0xffU;
+}