/* Orinoco MIC helpers
*
* See copyright notice in main.c
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/if_ether.h>
#include <linux/scatterlist.h>
#include <linux/crypto.h>
#include "orinoco.h"
#include "mic.h"
/********************************************************************/
/* Michael MIC crypto setup */
/********************************************************************/
int orinoco_mic_init(struct orinoco_private *priv)
{
priv->tx_tfm_mic = crypto_alloc_hash("michael_mic", 0, 0);
if (IS_ERR(priv->tx_tfm_mic)) {
printk(KERN_DEBUG "orinoco_mic_init: could not allocate "
"crypto API michael_mic\n");
priv->tx_tfm_mic = NULL;
return -ENOMEM;
}
priv->rx_tfm_mic = crypto_alloc_hash("michael_mic", 0, 0);
if (IS_ERR(priv->rx_tfm_mic)) {
printk(KERN_DEBUG "orinoco_mic_init: could not allocate "
"crypto API michael_mic\n");
priv->rx_tfm_mic = NULL;
return -ENOMEM;
}
return 0;
}
void orinoco_mic_free(struct orinoco_private *priv)
{
if (priv->tx_tfm_mic)
crypto_free_hash(priv->tx_tfm_mic);
if (priv->rx_tfm_mic)
crypto_free_hash(priv->rx_tfm_mic);
}
int orinoco_mic(struct crypto_hash *tfm_michael, u8 *key,
u8 *da, u8 *sa, u8 priority,
u8 *data, size_t data_len, u8 *mic)
{
struct hash_desc desc;
struct scatterlist sg[2];
u8 hdr[ETH_HLEN + 2]; /* size of header + padding */
if (tfm_michael == NULL) {
printk(KERN_WARNING "orinoco_mic: tfm_michael == NULL\n");
return -1;
}
/* Copy header into buffer. We need the padding on the end zeroed */
memcpy(&hdr[0], da, ETH_ALEN);
memcpy(&hdr[ETH_ALEN], sa, ETH_ALEN);
hdr[ETH_ALEN*2] = priority;
hdr[ETH_ALEN*2+1] = 0;
hdr[ETH_ALEN*2+2] = 0;
hdr[ETH_ALEN*2+3] = 0;
/* Use scatter gather to MIC header and data in one go */
sg_init_table(sg, 2);
sg_set_buf(&sg[0], hdr, sizeof(hdr));
sg_set_buf(&sg[1], data, data_len);
if (crypto_hash_setkey(tfm_michael, key, MIC_KEYLEN))
return -1;
desc.tfm = tfm_michael;
desc.flags = 0;
return crypto_hash_digest(&desc, sg, data_len + sizeof(hdr),
mic);
}
