freeswan/klips/net/ipsec/alg/ipsec_alg_aes.c

   1 /*
   2  * ipsec_alg AES cipher stubs
   3  *
   4  * Author: JuanJo Ciarlante <jjo-ipsec@mendoza.gov.ar>
   5  *
   6  * $Id: ipsec_alg_aes.c,v 1.2 2004-08-02 03:42:17 gerg Exp $
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2 of the License, or (at your
  11  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  * for more details.
  17  *
  18  */
  19 #include <linux/config.h>
  20 #include <linux/version.h>
  21
  22 /*
  23  *      special case: ipsec core modular with this static algo inside:
  24  *      must avoid MODULE magic for this file
  25  */
  26 #if CONFIG_IPSEC_MODULE && CONFIG_IPSEC_ALG_AES
  27 #undef MODULE
  28 #endif
  29
  30 #include <linux/module.h>
  31 #include <linux/init.h>
  32
  33 #include <linux/kernel.h> /* printk() */
  34 #include <linux/errno.h>  /* error codes */
  35 #include <linux/types.h>  /* size_t */
  36 #include <linux/string.h>
  37
  38 /* Check if __exit is defined, if not null it */
  39 #ifndef __exit
  40 #define __exit
  41 #endif
  42
  43 /*      Low freeswan header coupling    */
  44 #include "ipsec_alg.h"
  45 #include "libaes/aes_cbc.h"
  46
  47 #define CONFIG_IPSEC_ALG_AES_MAC 1
  48
  49 #define AES_CONTEXT_T aes_context
  50 MODULE_AUTHOR("JuanJo Ciarlante <jjo-ipsec@mendoza.gov.ar>");
  51 static int debug=0;
  52 MODULE_PARM(debug, "i");
  53 static int test=0;
  54 MODULE_PARM(test, "i");
  55 static int keyminbits=0;
  56 MODULE_PARM(keyminbits, "i");
  57 static int keymaxbits=0;
  58 MODULE_PARM(keymaxbits, "i");
  59
  60 #if CONFIG_IPSEC_ALG_AES_MAC
  61 #include "libaes/aes_xcbc_mac.h"
  62
  63 /*
  64  *      Not IANA number yet (draft-ietf-ipsec-ciph-aes-xcbc-mac-00.txt),
  65  *      force user to pass an id
  66  */
  67 static int auth_id=0;
  68 MODULE_PARM(auth_id, "i");
  69 #endif
  70
  71 #define ESP_AES                 12      /* truely _constant_  :)  */
  72
  73 /* 128, 192 or 256 */
  74 #define ESP_AES_KEY_SZ_MIN      16      /* 128 bit secret key */
  75 #define ESP_AES_KEY_SZ_MAX      32      /* 256 bit secret key */
  76 #define ESP_AES_CBC_BLK_LEN     16      /* AES-CBC block size */
  77
  78 static int _aes_set_key(__u8 * key_e, const __u8 * key, int keysize) {
  79         int ret;
  80         AES_CONTEXT_T *ctx=(AES_CONTEXT_T*)key_e;
  81         ret=AES_set_key(ctx, key, keysize)!=0? 0: -EINVAL;
  82         if (debug > 0)
  83                 printk(KERN_DEBUG "klips_debug:_aes_set_key:"
  84                                 "ret=%d key_e=%p key=%p keysize=%d\n",
  85                                 ret, key_e, key, keysize);
  86         return ret;
  87 }
  88 static int _aes_cbc_encrypt(__u8 * key_e, __u8 * in, __u8 * out, int ilen, const __u8 * iv, int encrypt) {
  89         AES_CONTEXT_T *ctx=(AES_CONTEXT_T*)key_e;
  90         if (debug > 0)
  91                 printk(KERN_DEBUG "klips_debug:_aes_cbc_encrypt:"
  92                                 "key_e=%p in=%p out=%p ilen=%d iv=%p encrypt=%d\n",
  93                                 key_e, in, out, ilen, iv, encrypt);
  94         return AES_cbc_encrypt(ctx, in, out, ilen, iv, encrypt);
  95 }
  96 #if CONFIG_IPSEC_ALG_AES_MAC
  97 static int _aes_mac_set_key(__u8 * key_a, const __u8 * key, int keylen) {
  98         aes_context_mac *ctxm=(aes_context_mac *)key_a;
  99         return AES_xcbc_mac_set_key(ctxm, key, keylen)? 0 : -EINVAL;
 100 }
 101 static int _aes_mac_hash(__u8 * key_a, const __u8 * dat, int len, __u8 * hash, int hashlen) {
 102         int ret;
 103         char hash_buf[16];
 104         aes_context_mac *ctxm=(aes_context_mac *)key_a;
 105         ret=AES_xcbc_mac_hash(ctxm, dat, len, hash_buf);
 106         memcpy(hash, hash_buf, hashlen);
 107         return ret;
 108 }
 109 static struct ipsec_alg_auth ipsec_alg_AES_MAC = {
 110         ixt_version:    IPSEC_ALG_VERSION,
 111         ixt_module:     THIS_MODULE,
 112         ixt_refcnt:     ATOMIC_INIT(0),
 113         ixt_alg_type:   IPSEC_ALG_TYPE_AUTH,
 114         ixt_alg_id:     0,
 115         ixt_name:       "aes_mac",
 116         ixt_blocksize:  ESP_AES_CBC_BLK_LEN,
 117         ixt_keyminbits: ESP_AES_KEY_SZ_MIN*8,
 118         ixt_keymaxbits: ESP_AES_KEY_SZ_MAX*8,
 119         ixt_a_keylen:   ESP_AES_KEY_SZ_MAX,
 120         ixt_a_ctx_size: sizeof(aes_context_mac),
 121         ixt_a_hmac_set_key:     _aes_mac_set_key,
 122         ixt_a_hmac_hash:_aes_mac_hash,
 123 };
 124 #endif /* CONFIG_IPSEC_ALG_AES_MAC */
 125 static struct ipsec_alg_enc ipsec_alg_AES = {
 126         ixt_version:    IPSEC_ALG_VERSION,
 127         ixt_module:     THIS_MODULE,
 128         ixt_refcnt:     ATOMIC_INIT(0),
 129         ixt_alg_type:   IPSEC_ALG_TYPE_ENCRYPT,
 130         ixt_alg_id:     ESP_AES,
 131         ixt_name:       "aes",
 132         ixt_blocksize:  ESP_AES_CBC_BLK_LEN,
 133         ixt_keyminbits: ESP_AES_KEY_SZ_MIN*8,
 134         ixt_keymaxbits: ESP_AES_KEY_SZ_MAX*8,
 135         ixt_e_keylen:   ESP_AES_KEY_SZ_MAX,
 136         ixt_e_ctx_size: sizeof(AES_CONTEXT_T),
 137         ixt_e_set_key:  _aes_set_key,
 138         ixt_e_cbc_encrypt:_aes_cbc_encrypt,
 139 };
 140
 141 IPSEC_ALG_MODULE_INIT( ipsec_aes_init )
 142 {
 143         int ret, test_ret;
 144         if (keyminbits)
 145                 ipsec_alg_AES.ixt_keyminbits=keyminbits;
 146         if (keymaxbits) {
 147                 ipsec_alg_AES.ixt_keymaxbits=keymaxbits;
 148                 if (keymaxbits*8>ipsec_alg_AES.ixt_keymaxbits)
 149                         ipsec_alg_AES.ixt_e_keylen=keymaxbits*8;
 150         }
 151         ret=register_ipsec_alg_enc(&ipsec_alg_AES);
 152         printk("%s(alg_type=%d alg_id=%d name=%s): ret=%d\n",
 153                         __FUNCTION__,
 154                         ipsec_alg_AES.ixt_alg_type,
 155                         ipsec_alg_AES.ixt_alg_id,
 156                         ipsec_alg_AES.ixt_name,
 157                         ret);
 158         if (ret==0 && test) {
 159                 test_ret=ipsec_alg_test(
 160                                 ipsec_alg_AES.ixt_alg_type,
 161                                 ipsec_alg_AES.ixt_alg_id,
 162                                 test);
 163                 printk("%s(alg_type=%d alg_id=%d): test_ret=%d\n",
 164                                 __FUNCTION__,
 165                                 ipsec_alg_AES.ixt_alg_type,
 166                                 ipsec_alg_AES.ixt_alg_id,
 167                                 test_ret);
 168         }
 169 #if CONFIG_IPSEC_ALG_AES_MAC
 170         if (auth_id!=0){
 171                 int ret;
 172                 ipsec_alg_AES_MAC.ixt_alg_id=auth_id;
 173                 ret=register_ipsec_alg_auth(&ipsec_alg_AES_MAC);
 174                 printk("%s(alg_type=%d alg_id=%d name=%s): ret=%d\n",
 175                                 __FUNCTION__,
 176                                 ipsec_alg_AES_MAC.ixt_alg_type,
 177                                 ipsec_alg_AES_MAC.ixt_alg_id,
 178                                 ipsec_alg_AES_MAC.ixt_name,
 179                                 ret);
 180                 if (ret==0 && test) {
 181                         test_ret=ipsec_alg_test(
 182                                         ipsec_alg_AES_MAC.ixt_alg_type,
 183                                         ipsec_alg_AES_MAC.ixt_alg_id,
 184                                         test);
 185                         printk("%s(alg_type=%d alg_id=%d): test_ret=%d\n",
 186                                         __FUNCTION__,
 187                                         ipsec_alg_AES_MAC.ixt_alg_type,
 188                                         ipsec_alg_AES_MAC.ixt_alg_id,
 189                                         test_ret);
 190                 }
 191         } else {
 192                 printk(KERN_DEBUG "klips_debug: experimental ipsec_alg_AES_MAC not registered [Ok] (auth_id=%d)\n", auth_id);
 193         }
 194 #endif /* CONFIG_IPSEC_ALG_AES_MAC */
 195         return ret;
 196 }
 197 IPSEC_ALG_MODULE_EXIT( ipsec_aes_fini )
 198 {
 199 #if CONFIG_IPSEC_ALG_AES_MAC
 200         if (auth_id) unregister_ipsec_alg_auth(&ipsec_alg_AES_MAC);
 201 #endif /* CONFIG_IPSEC_ALG_AES_MAC */
 202         unregister_ipsec_alg_enc(&ipsec_alg_AES);
 203         return;
 204 }
 205 #ifdef MODULE_LICENSE
 206 MODULE_LICENSE("GPL");
 207 #endif
 208
 209 EXPORT_NO_SYMBOLS;