2 * MD5 hash implementation and interface functions
3 * Copyright (c) 2003-2005, Jouni Malinen <j@w1.fi>
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
17 * hmac_md5_vector - HMAC-MD5 over data vector (RFC 2104)
18 * @key: Key for HMAC operations
19 * @key_len: Length of the key in bytes
20 * @num_elem: Number of elements in the data vector
21 * @addr: Pointers to the data areas
22 * @len: Lengths of the data blocks
23 * @mac: Buffer for the hash (16 bytes)
24 * Returns: 0 on success, -1 on failure
26 int hmac_md5_vector(const u8 *key, size_t key_len, size_t num_elem,
27 const u8 *addr[], const size_t *len, u8 *mac)
29 u8 k_pad[64]; /* padding - key XORd with ipad/opad */
37 * Fixed limit on the number of fragments to avoid having to
38 * allocate memory (which could fail).
43 /* if key is longer than 64 bytes reset it to key = MD5(key) */
45 if (md5_vector(1, &key, &key_len, tk))
51 /* the HMAC_MD5 transform looks like:
53 * MD5(K XOR opad, MD5(K XOR ipad, text))
55 * where K is an n byte key
56 * ipad is the byte 0x36 repeated 64 times
57 * opad is the byte 0x5c repeated 64 times
58 * and text is the data being protected */
60 /* start out by storing key in ipad */
61 os_memset(k_pad, 0, sizeof(k_pad));
62 os_memcpy(k_pad, key, key_len);
64 /* XOR key with ipad values */
65 for (i = 0; i < 64; i++)
68 /* perform inner MD5 */
71 for (i = 0; i < num_elem; i++) {
72 _addr[i + 1] = addr[i];
75 if (md5_vector(1 + num_elem, _addr, _len, mac))
78 os_memset(k_pad, 0, sizeof(k_pad));
79 os_memcpy(k_pad, key, key_len);
80 /* XOR key with opad values */
81 for (i = 0; i < 64; i++)
84 /* perform outer MD5 */
88 _len[1] = MD5_MAC_LEN;
89 res = md5_vector(2, _addr, _len, mac);
90 os_memset(k_pad, 0, sizeof(k_pad));
91 os_memset(tk, 0, sizeof(tk));
97 * hmac_md5 - HMAC-MD5 over data buffer (RFC 2104)
98 * @key: Key for HMAC operations
99 * @key_len: Length of the key in bytes
100 * @data: Pointers to the data area
101 * @data_len: Length of the data area
102 * @mac: Buffer for the hash (16 bytes)
103 * Returns: 0 on success, -1 on failure
105 int hmac_md5(const u8 *key, size_t key_len, const u8 *data, size_t data_len,
108 return hmac_md5_vector(key, key_len, 1, &data, &data_len, mac);