root/drivers/net/wireless/intersil/orinoco/mic.c

DEFINITIONS

1. orinoco_mic_init
2. orinoco_mic_free
3. orinoco_mic

   1 /* Orinoco MIC helpers
   2  *
   3  * See copyright notice in main.c
   4  */
   5 #include <linux/kernel.h>
   6 #include <linux/string.h>
   7 #include <linux/if_ether.h>
   8 #include <linux/scatterlist.h>
   9 #include <crypto/hash.h>
  10 
  11 #include "orinoco.h"
  12 #include "mic.h"
  13 
  14 /********************************************************************/
  15 /* Michael MIC crypto setup                                         */
  16 /********************************************************************/
  17 int orinoco_mic_init(struct orinoco_private *priv)
  18 {
  19         priv->tx_tfm_mic = crypto_alloc_shash("michael_mic", 0, 0);
  20         if (IS_ERR(priv->tx_tfm_mic)) {
  21                 printk(KERN_DEBUG "%s: could not allocate "
  22                        "crypto API michael_mic\n", __func__);
  23                 priv->tx_tfm_mic = NULL;
  24                 return -ENOMEM;
  25         }
  26 
  27         priv->rx_tfm_mic = crypto_alloc_shash("michael_mic", 0, 0);
  28         if (IS_ERR(priv->rx_tfm_mic)) {
  29                 printk(KERN_DEBUG "%s: could not allocate "
  30                        "crypto API michael_mic\n", __func__);
  31                 priv->rx_tfm_mic = NULL;
  32                 return -ENOMEM;
  33         }
  34 
  35         return 0;
  36 }
  37 
  38 void orinoco_mic_free(struct orinoco_private *priv)
  39 {
  40         if (priv->tx_tfm_mic)
  41                 crypto_free_shash(priv->tx_tfm_mic);
  42         if (priv->rx_tfm_mic)
  43                 crypto_free_shash(priv->rx_tfm_mic);
  44 }
  45 
  46 int orinoco_mic(struct crypto_shash *tfm_michael, u8 *key,
  47                 u8 *da, u8 *sa, u8 priority,
  48                 u8 *data, size_t data_len, u8 *mic)
  49 {
  50         SHASH_DESC_ON_STACK(desc, tfm_michael);
  51         u8 hdr[ETH_HLEN + 2]; /* size of header + padding */
  52         int err;
  53 
  54         if (tfm_michael == NULL) {
  55                 printk(KERN_WARNING "%s: tfm_michael == NULL\n", __func__);
  56                 return -1;
  57         }
  58 
  59         /* Copy header into buffer. We need the padding on the end zeroed */
  60         memcpy(&hdr[0], da, ETH_ALEN);
  61         memcpy(&hdr[ETH_ALEN], sa, ETH_ALEN);
  62         hdr[ETH_ALEN * 2] = priority;
  63         hdr[ETH_ALEN * 2 + 1] = 0;
  64         hdr[ETH_ALEN * 2 + 2] = 0;
  65         hdr[ETH_ALEN * 2 + 3] = 0;
  66 
  67         desc->tfm = tfm_michael;
  68 
  69         err = crypto_shash_setkey(tfm_michael, key, MIC_KEYLEN);
  70         if (err)
  71                 return err;
  72 
  73         err = crypto_shash_init(desc);
  74         if (err)
  75                 return err;
  76 
  77         err = crypto_shash_update(desc, hdr, sizeof(hdr));
  78         if (err)
  79                 return err;
  80 
  81         err = crypto_shash_update(desc, data, data_len);
  82         if (err)
  83                 return err;
  84 
  85         err = crypto_shash_final(desc, mic);
  86         shash_desc_zero(desc);
  87 
  88         return err;
  89 }