target/linux/generic-2.6/files/crypto/ocf/ocfnull/ocfnull.c

   1 /*
   2  * An OCF module for determining the cost of crypto versus the cost of
   3  * IPSec processing outside of OCF.  This modules gives us the effect of
   4  * zero cost encryption,  of course you will need to run it at both ends
   5  * since it does no crypto at all.
   6  *
   7  * Written by David McCullough <david_mccullough@mcafee.com>
   8  * Copyright (C) 2006-2010 David McCullough
   9  *
  10  * LICENSE TERMS
  11  *
  12  * The free distribution and use of this software in both source and binary
  13  * form is allowed (with or without changes) provided that:
  14  *
  15  *   1. distributions of this source code include the above copyright
  16  *      notice, this list of conditions and the following disclaimer;
  17  *
  18  *   2. distributions in binary form include the above copyright
  19  *      notice, this list of conditions and the following disclaimer
  20  *      in the documentation and/or other associated materials;
  21  *
  22  *   3. the copyright holder's name is not used to endorse products
  23  *      built using this software without specific written permission.
  24  *
  25  * ALTERNATIVELY, provided that this notice is retained in full, this product
  26  * may be distributed under the terms of the GNU General Public License (GPL),
  27  * in which case the provisions of the GPL apply INSTEAD OF those given above.
  28  *
  29  * DISCLAIMER
  30  *
  31  * This software is provided 'as is' with no explicit or implied warranties
  32  * in respect of its properties, including, but not limited to, correctness
  33  * and/or fitness for purpose.
  34  */
  35
  36 #ifndef AUTOCONF_INCLUDED
  37 #include <linux/config.h>
  38 #endif
  39 #include <linux/module.h>
  40 #include <linux/init.h>
  41 #include <linux/list.h>
  42 #include <linux/slab.h>
  43 #include <linux/sched.h>
  44 #include <linux/wait.h>
  45 #include <linux/crypto.h>
  46 #include <linux/interrupt.h>
  47
  48 #include <cryptodev.h>
  49 #include <uio.h>
  50
  51 static int32_t                   null_id = -1;
  52 static u_int32_t                 null_sesnum = 0;
  53
  54 static int null_process(device_t, struct cryptop *, int);
  55 static int null_newsession(device_t, u_int32_t *, struct cryptoini *);
  56 static int null_freesession(device_t, u_int64_t);
  57
  58 #define debug ocfnull_debug
  59 int ocfnull_debug = 0;
  60 module_param(ocfnull_debug, int, 0644);
  61 MODULE_PARM_DESC(ocfnull_debug, "Enable debug");
  62
  63 /*
  64  * dummy device structure
  65  */
  66
  67 static struct {
  68         softc_device_decl       sc_dev;
  69 } nulldev;
  70
  71 static device_method_t null_methods = {
  72         /* crypto device methods */
  73         DEVMETHOD(cryptodev_newsession, null_newsession),
  74         DEVMETHOD(cryptodev_freesession,null_freesession),
  75         DEVMETHOD(cryptodev_process,    null_process),
  76 };
  77
  78 /*
  79  * Generate a new software session.
  80  */
  81 static int
  82 null_newsession(device_t arg, u_int32_t *sid, struct cryptoini *cri)
  83 {
  84         dprintk("%s()\n", __FUNCTION__);
  85         if (sid == NULL || cri == NULL) {
  86                 dprintk("%s,%d - EINVAL\n", __FILE__, __LINE__);
  87                 return EINVAL;
  88         }
  89
  90         if (null_sesnum == 0)
  91                 null_sesnum++;
  92         *sid = null_sesnum++;
  93         return 0;
  94 }
  95
  96
  97 /*
  98  * Free a session.
  99  */
 100 static int
 101 null_freesession(device_t arg, u_int64_t tid)
 102 {
 103         u_int32_t sid = CRYPTO_SESID2LID(tid);
 104
 105         dprintk("%s()\n", __FUNCTION__);
 106         if (sid > null_sesnum) {
 107                 dprintk("%s,%d: EINVAL\n", __FILE__, __LINE__);
 108                 return EINVAL;
 109         }
 110
 111         /* Silently accept and return */
 112         if (sid == 0)
 113                 return 0;
 114         return 0;
 115 }
 116
 117
 118 /*
 119  * Process a request.
 120  */
 121 static int
 122 null_process(device_t arg, struct cryptop *crp, int hint)
 123 {
 124         unsigned int lid;
 125
 126         dprintk("%s()\n", __FUNCTION__);
 127
 128         /* Sanity check */
 129         if (crp == NULL) {
 130                 dprintk("%s,%d: EINVAL\n", __FILE__, __LINE__);
 131                 return EINVAL;
 132         }
 133
 134         crp->crp_etype = 0;
 135
 136         if (crp->crp_desc == NULL || crp->crp_buf == NULL) {
 137                 dprintk("%s,%d: EINVAL\n", __FILE__, __LINE__);
 138                 crp->crp_etype = EINVAL;
 139                 goto done;
 140         }
 141
 142         /*
 143          * find the session we are using
 144          */
 145
 146         lid = crp->crp_sid & 0xffffffff;
 147         if (lid >= null_sesnum || lid == 0) {
 148                 crp->crp_etype = ENOENT;
 149                 dprintk("%s,%d: ENOENT\n", __FILE__, __LINE__);
 150                 goto done;
 151         }
 152
 153 done:
 154         crypto_done(crp);
 155         return 0;
 156 }
 157
 158
 159 /*
 160  * our driver startup and shutdown routines
 161  */
 162
 163 static int
 164 null_init(void)
 165 {
 166         dprintk("%s(%p)\n", __FUNCTION__, null_init);
 167
 168         memset(&nulldev, 0, sizeof(nulldev));
 169         softc_device_init(&nulldev, "ocfnull", 0, null_methods);
 170
 171         null_id = crypto_get_driverid(softc_get_device(&nulldev),
 172                                 CRYPTOCAP_F_HARDWARE);
 173         if (null_id < 0)
 174                 panic("ocfnull: crypto device cannot initialize!");
 175
 176 #define REGISTER(alg) \
 177         crypto_register(null_id,alg,0,0)
 178         REGISTER(CRYPTO_DES_CBC);
 179         REGISTER(CRYPTO_3DES_CBC);
 180         REGISTER(CRYPTO_RIJNDAEL128_CBC);
 181         REGISTER(CRYPTO_MD5);
 182         REGISTER(CRYPTO_SHA1);
 183         REGISTER(CRYPTO_MD5_HMAC);
 184         REGISTER(CRYPTO_SHA1_HMAC);
 185 #undef REGISTER
 186
 187         return 0;
 188 }
 189
 190 static void
 191 null_exit(void)
 192 {
 193         dprintk("%s()\n", __FUNCTION__);
 194         crypto_unregister_all(null_id);
 195         null_id = -1;
 196 }
 197
 198 module_init(null_init);
 199 module_exit(null_exit);
 200
 201 MODULE_LICENSE("Dual BSD/GPL");
 202 MODULE_AUTHOR("David McCullough <david_mccullough@mcafee.com>");
 203 MODULE_DESCRIPTION("ocfnull - claims a lot but does nothing");