xref: /linux/security/selinux/ss/symtab.c (revision 2697b79a469b68e3ad3640f55284359c1396278d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Implementation of the symbol table type.
4  *
5  * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/string.h>
10 #include <linux/errno.h>
11 #include "symtab.h"
12 
13 static unsigned int symhash(const void *key)
14 {
15 	/*
16 	 * djb2a
17 	 * Public domain from cdb v0.75
18 	 */
19 	unsigned int hash = 5381;
20 	unsigned char c;
21 
22 	while ((c = *(const unsigned char *)key++))
23 		hash = ((hash << 5) + hash) ^ c;
24 
25 	return hash;
26 }
27 
28 static int symcmp(const void *key1, const void *key2)
29 {
30 	const char *keyp1, *keyp2;
31 
32 	keyp1 = key1;
33 	keyp2 = key2;
34 	return strcmp(keyp1, keyp2);
35 }
36 
37 static const struct hashtab_key_params symtab_key_params = {
38 	.hash = symhash,
39 	.cmp = symcmp,
40 };
41 
42 int symtab_init(struct symtab *s, u32 size)
43 {
44 	s->nprim = 0;
45 	return hashtab_init(&s->table, size);
46 }
47 
48 int symtab_insert(struct symtab *s, char *name, void *datum)
49 {
50 	return hashtab_insert(&s->table, name, datum, symtab_key_params);
51 }
52 
53 void *symtab_search(struct symtab *s, const char *name)
54 {
55 	return hashtab_search(&s->table, name, symtab_key_params);
56 }
57