1 /*
2 +----------------------------------------------------------------------+
3 | Copyright (c) The PHP Group |
4 +----------------------------------------------------------------------+
5 | This source file is subject to version 3.01 of the PHP license, |
6 | that is bundled with this package in the file LICENSE, and is |
7 | available through the world-wide-web at the following url: |
8 | http://www.php.net/license/3_01.txt |
9 | If you did not receive a copy of the PHP license and are unable to |
10 | obtain it through the world-wide-web, please send a note to |
11 | license@php.net so we can mail you a copy immediately. |
12 +----------------------------------------------------------------------+
13 | Author: Martin Jansen <mj@php.net> |
14 +----------------------------------------------------------------------+
15 */
16
17 /* Implements Jenkins's one-at-a-time hashing algorithm as presented on
18 * http://www.burtleburtle.net/bob/hash/doobs.html.
19 */
20
21 #include "php_hash.h"
22 #include "php_hash_joaat.h"
23
24 const php_hash_ops php_hash_joaat_ops = {
25 "joaat",
26 (php_hash_init_func_t) PHP_JOAATInit,
27 (php_hash_update_func_t) PHP_JOAATUpdate,
28 (php_hash_final_func_t) PHP_JOAATFinal,
29 php_hash_copy,
30 php_hash_serialize,
31 php_hash_unserialize,
32 PHP_JOAAT_SPEC,
33 4,
34 4,
35 sizeof(PHP_JOAAT_CTX),
36 0
37 };
38
PHP_JOAATInit(PHP_JOAAT_CTX * context)39 PHP_HASH_API void PHP_JOAATInit(PHP_JOAAT_CTX *context)
40 {
41 context->state = 0;
42 }
43
PHP_JOAATUpdate(PHP_JOAAT_CTX * context,const unsigned char * input,size_t inputLen)44 PHP_HASH_API void PHP_JOAATUpdate(PHP_JOAAT_CTX *context, const unsigned char *input, size_t inputLen)
45 {
46 context->state = joaat_buf((void *)input, inputLen, context->state);
47 }
48
PHP_JOAATFinal(unsigned char digest[4],PHP_JOAAT_CTX * context)49 PHP_HASH_API void PHP_JOAATFinal(unsigned char digest[4], PHP_JOAAT_CTX * context)
50 {
51 uint32_t hval = context->state;
52 hval += (hval << 3);
53 hval ^= (hval >> 11);
54 hval += (hval << 15);
55
56 #ifdef WORDS_BIGENDIAN
57 memcpy(digest, &hval, 4);
58 #else
59 int i = 0;
60 unsigned char *c = (unsigned char *) &hval;
61
62 for (i = 0; i < 4; i++) {
63 digest[i] = c[3 - i];
64 }
65 #endif
66 context->state = 0;
67 }
68
69 /*
70 * joaat_buf - perform a Jenkins's one-at-a-time hash on a buffer
71 *
72 * input:
73 * buf - start of buffer to hash
74 * len - length of buffer in octets
75 *
76 * returns:
77 * 32 bit hash as a static hash type
78 */
79 static uint32_t
joaat_buf(void * buf,size_t len,uint32_t hval)80 joaat_buf(void *buf, size_t len, uint32_t hval)
81 {
82 size_t i;
83 unsigned char *input = (unsigned char *)buf;
84
85 for (i = 0; i < len; i++) {
86 hval += input[i];
87 hval += (hval << 10);
88 hval ^= (hval >> 6);
89 }
90
91 return hval;
92 }
93
