xref: /openbmc/linux/security/selinux/ss/symtab.c (revision 12eb4683)
1 /*
2  * Implementation of the symbol table type.
3  *
4  * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
5  */
6 #include <linux/kernel.h>
7 #include <linux/string.h>
8 #include <linux/errno.h>
9 #include "symtab.h"
10 
11 static unsigned int symhash(struct hashtab *h, const void *key)
12 {
13 	const char *p, *keyp;
14 	unsigned int size;
15 	unsigned int val;
16 
17 	val = 0;
18 	keyp = key;
19 	size = strlen(keyp);
20 	for (p = keyp; (p - keyp) < size; p++)
21 		val = (val << 4 | (val >> (8*sizeof(unsigned int)-4))) ^ (*p);
22 	return val & (h->size - 1);
23 }
24 
25 static int symcmp(struct hashtab *h, const void *key1, const void *key2)
26 {
27 	const char *keyp1, *keyp2;
28 
29 	keyp1 = key1;
30 	keyp2 = key2;
31 	return strcmp(keyp1, keyp2);
32 }
33 
34 
35 int symtab_init(struct symtab *s, unsigned int size)
36 {
37 	s->table = hashtab_create(symhash, symcmp, size);
38 	if (!s->table)
39 		return -ENOMEM;
40 	s->nprim = 0;
41 	return 0;
42 }
43 
44