xref: /linux/security/selinux/ss/symtab.c (revision c79c3c34f75d72a066e292b10aa50fc758c97c89)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Implementation of the symbol table type.
4  *
5  * Author : Stephen Smalley, <sds@tycho.nsa.gov>
6  */
7 #include <linux/kernel.h>
8 #include <linux/string.h>
9 #include <linux/errno.h>
10 #include "symtab.h"
11 
12 static unsigned int symhash(const void *key)
13 {
14 	const char *p, *keyp;
15 	unsigned int size;
16 	unsigned int val;
17 
18 	val = 0;
19 	keyp = key;
20 	size = strlen(keyp);
21 	for (p = keyp; (p - keyp) < size; p++)
22 		val = (val << 4 | (val >> (8*sizeof(unsigned int)-4))) ^ (*p);
23 	return val;
24 }
25 
26 static int symcmp(const void *key1, const void *key2)
27 {
28 	const char *keyp1, *keyp2;
29 
30 	keyp1 = key1;
31 	keyp2 = key2;
32 	return strcmp(keyp1, keyp2);
33 }
34 
35 static const struct hashtab_key_params symtab_key_params = {
36 	.hash = symhash,
37 	.cmp = symcmp,
38 };
39 
40 int symtab_init(struct symtab *s, unsigned int size)
41 {
42 	s->nprim = 0;
43 	return hashtab_init(&s->table, size);
44 }
45 
46 int symtab_insert(struct symtab *s, char *name, void *datum)
47 {
48 	return hashtab_insert(&s->table, name, datum, symtab_key_params);
49 }
50 
51 void *symtab_search(struct symtab *s, const char *name)
52 {
53 	return hashtab_search(&s->table, name, symtab_key_params);
54 }
55