1/*-
2 * SPDX-License-Identifier: BSD-4-Clause
3 *
4 * Copyright (c) 1995
5 *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by Bill Paul.
18 * 4. Neither the name of the author nor the names of any co-contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <stdio.h>
36#include <stdlib.h>
37#include <string.h>
38#include <sys/types.h>
39#include "hash.h"
40
41#ifndef lint
42static const char rcsid[] =
43  "$FreeBSD$";
44#endif /* not lint */
45
46/*
47 * This hash function is stolen directly from the
48 * Berkeley DB package. It already exists inside libc, but
49 * it's declared static which prevents us from calling it
50 * from here.
51 */
52/*
53 * OZ's original sdbm hash
54 */
55u_int32_t
56hash(const void *keyarg, size_t len)
57{
58	const u_char *key;
59	size_t loop;
60	u_int32_t h;
61
62#define HASHC   h = *key++ + 65599 * h
63
64	h = 0;
65	key = keyarg;
66	if (len > 0) {
67		loop = (len + 8 - 1) >> 3;
68
69		switch (len & (8 - 1)) {
70		case 0:
71			do {
72				HASHC;
73				/* FALLTHROUGH */
74		case 7:
75				HASHC;
76				/* FALLTHROUGH */
77		case 6:
78				HASHC;
79				/* FALLTHROUGH */
80		case 5:
81				HASHC;
82				/* FALLTHROUGH */
83		case 4:
84				HASHC;
85				/* FALLTHROUGH */
86		case 3:
87				HASHC;
88				/* FALLTHROUGH */
89		case 2:
90				HASHC;
91				/* FALLTHROUGH */
92		case 1:
93				HASHC;
94			} while (--loop);
95		}
96	}
97	return (h);
98}
99
100/*
101 * Generate a hash value for a given key (character string).
102 * We mask off all but the lower 8 bits since our table array
103 * can only hole 256 elements.
104 */
105u_int32_t hashkey(char *key)
106{
107
108	if (key == NULL)
109		return (-1);
110	return(hash((void *)key, strlen(key)) & HASH_MASK);
111}
112
113/* Find an entry in the hash table (may be hanging off a linked list). */
114struct grouplist *lookup(struct member_entry *table[], char *key)
115{
116	struct member_entry *cur;
117
118	cur = table[hashkey(key)];
119
120	while (cur) {
121		if (!strcmp(cur->key, key))
122			return(cur->groups);
123		cur = cur->next;
124	}
125
126	return(NULL);
127}
128
129struct grouplist dummy = { 99999, NULL };
130
131/*
132 * Store a group member entry and/or update its grouplist.
133 */
134void mstore (struct member_entry *table[], char *key, int gid, int dup)
135{
136	struct member_entry *cur, *new;
137	struct grouplist *tmp;
138	u_int32_t i;
139
140	i = hashkey(key);
141	cur = table[i];
142
143	if (!dup) {
144		tmp = (struct grouplist *)malloc(sizeof(struct grouplist));
145		tmp->groupid = gid;
146		tmp->next = NULL;
147	}
148
149		/* Check if all we have to do is insert a new groupname. */
150	while (cur) {
151		if (!dup && !strcmp(cur->key, key)) {
152			tmp->next = cur->groups;
153			cur->groups = tmp;
154			return;
155		}
156		cur = cur->next;
157	}
158
159	/* Didn't find a match -- add the whole mess to the table. */
160	new = (struct member_entry *)malloc(sizeof(struct member_entry));
161	new->key = strdup(key);
162	if (!dup)
163		new->groups = tmp;
164	else
165		new->groups = (struct grouplist *)&dummy;
166	new->next = table[i];
167	table[i] = new;
168
169	return;
170}
171