drivers/crypto/ccp/ccp-crypto-des3.c

   1 /*
   2  * AMD Cryptographic Coprocessor (CCP) DES3 crypto API support
   3  *
   4  * Copyright (C) 2016,2017 Advanced Micro Devices, Inc.
   5  *
   6  * Author: Gary R Hook <ghook@amd.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/sched.h>
  15 #include <linux/delay.h>
  16 #include <linux/scatterlist.h>
  17 #include <linux/crypto.h>
  18 #include <crypto/algapi.h>
  19 #include <crypto/scatterwalk.h>
  20 #include <crypto/des.h>
  21
  22 #include "ccp-crypto.h"
  23
  24 static int ccp_des3_complete(struct crypto_async_request *async_req, int ret)
  25 {
  26         struct ablkcipher_request *req = ablkcipher_request_cast(async_req);
  27         struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
  28         struct ccp_des3_req_ctx *rctx = ablkcipher_request_ctx(req);
  29
  30         if (ret)
  31                 return ret;
  32
  33         if (ctx->u.des3.mode != CCP_DES3_MODE_ECB)
  34                 memcpy(req->info, rctx->iv, DES3_EDE_BLOCK_SIZE);
  35
  36         return 0;
  37 }
  38
  39 static int ccp_des3_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
  40                 unsigned int key_len)
  41 {
  42         struct ccp_ctx *ctx = crypto_tfm_ctx(crypto_ablkcipher_tfm(tfm));
  43         struct ccp_crypto_ablkcipher_alg *alg =
  44                 ccp_crypto_ablkcipher_alg(crypto_ablkcipher_tfm(tfm));
  45         u32 *flags = &tfm->base.crt_flags;
  46
  47
  48         /* From des_generic.c:
  49          *
  50          * RFC2451:
  51          *   If the first two or last two independent 64-bit keys are
  52          *   equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
  53          *   same as DES.  Implementers MUST reject keys that exhibit this
  54          *   property.
  55          */
  56         const u32 *K = (const u32 *)key;
  57
  58         if (unlikely(!((K[0] ^ K[2]) | (K[1] ^ K[3])) ||
  59                      !((K[2] ^ K[4]) | (K[3] ^ K[5]))) &&
  60                      (*flags & CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)) {
  61                 *flags |= CRYPTO_TFM_RES_WEAK_KEY;
  62                 return -EINVAL;
  63         }
  64
  65         /* It's not clear that there is any support for a keysize of 112.
  66          * If needed, the caller should make K1 == K3
  67          */
  68         ctx->u.des3.type = CCP_DES3_TYPE_168;
  69         ctx->u.des3.mode = alg->mode;
  70         ctx->u.des3.key_len = key_len;
  71
  72         memcpy(ctx->u.des3.key, key, key_len);
  73         sg_init_one(&ctx->u.des3.key_sg, ctx->u.des3.key, key_len);
  74
  75         return 0;
  76 }
  77
  78 static int ccp_des3_crypt(struct ablkcipher_request *req, bool encrypt)
  79 {
  80         struct ccp_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
  81         struct ccp_des3_req_ctx *rctx = ablkcipher_request_ctx(req);
  82         struct scatterlist *iv_sg = NULL;
  83         unsigned int iv_len = 0;
  84         int ret;
  85
  86         if (!ctx->u.des3.key_len)
  87                 return -EINVAL;
  88
  89         if (((ctx->u.des3.mode == CCP_DES3_MODE_ECB) ||
  90              (ctx->u.des3.mode == CCP_DES3_MODE_CBC)) &&
  91             (req->nbytes & (DES3_EDE_BLOCK_SIZE - 1)))
  92                 return -EINVAL;
  93
  94         if (ctx->u.des3.mode != CCP_DES3_MODE_ECB) {
  95                 if (!req->info)
  96                         return -EINVAL;
  97
  98                 memcpy(rctx->iv, req->info, DES3_EDE_BLOCK_SIZE);
  99                 iv_sg = &rctx->iv_sg;
 100                 iv_len = DES3_EDE_BLOCK_SIZE;
 101                 sg_init_one(iv_sg, rctx->iv, iv_len);
 102         }
 103
 104         memset(&rctx->cmd, 0, sizeof(rctx->cmd));
 105         INIT_LIST_HEAD(&rctx->cmd.entry);
 106         rctx->cmd.engine = CCP_ENGINE_DES3;
 107         rctx->cmd.u.des3.type = ctx->u.des3.type;
 108         rctx->cmd.u.des3.mode = ctx->u.des3.mode;
 109         rctx->cmd.u.des3.action = (encrypt)
 110                                   ? CCP_DES3_ACTION_ENCRYPT
 111                                   : CCP_DES3_ACTION_DECRYPT;
 112         rctx->cmd.u.des3.key = &ctx->u.des3.key_sg;
 113         rctx->cmd.u.des3.key_len = ctx->u.des3.key_len;
 114         rctx->cmd.u.des3.iv = iv_sg;
 115         rctx->cmd.u.des3.iv_len = iv_len;
 116         rctx->cmd.u.des3.src = req->src;
 117         rctx->cmd.u.des3.src_len = req->nbytes;
 118         rctx->cmd.u.des3.dst = req->dst;
 119
 120         ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
 121
 122         return ret;
 123 }
 124
 125 static int ccp_des3_encrypt(struct ablkcipher_request *req)
 126 {
 127         return ccp_des3_crypt(req, true);
 128 }
 129
 130 static int ccp_des3_decrypt(struct ablkcipher_request *req)
 131 {
 132         return ccp_des3_crypt(req, false);
 133 }
 134
 135 static int ccp_des3_cra_init(struct crypto_tfm *tfm)
 136 {
 137         struct ccp_ctx *ctx = crypto_tfm_ctx(tfm);
 138
 139         ctx->complete = ccp_des3_complete;
 140         ctx->u.des3.key_len = 0;
 141
 142         tfm->crt_ablkcipher.reqsize = sizeof(struct ccp_des3_req_ctx);
 143
 144         return 0;
 145 }
 146
 147 static void ccp_des3_cra_exit(struct crypto_tfm *tfm)
 148 {
 149 }
 150
 151 static struct crypto_alg ccp_des3_defaults = {
 152         .cra_flags      = CRYPTO_ALG_TYPE_ABLKCIPHER |
 153                 CRYPTO_ALG_ASYNC |
 154                 CRYPTO_ALG_KERN_DRIVER_ONLY |
 155                 CRYPTO_ALG_NEED_FALLBACK,
 156         .cra_blocksize  = DES3_EDE_BLOCK_SIZE,
 157         .cra_ctxsize    = sizeof(struct ccp_ctx),
 158         .cra_priority   = CCP_CRA_PRIORITY,
 159         .cra_type       = &crypto_ablkcipher_type,
 160         .cra_init       = ccp_des3_cra_init,
 161         .cra_exit       = ccp_des3_cra_exit,
 162         .cra_module     = THIS_MODULE,
 163         .cra_ablkcipher = {
 164                 .setkey         = ccp_des3_setkey,
 165                 .encrypt        = ccp_des3_encrypt,
 166                 .decrypt        = ccp_des3_decrypt,
 167                 .min_keysize    = DES3_EDE_KEY_SIZE,
 168                 .max_keysize    = DES3_EDE_KEY_SIZE,
 169         },
 170 };
 171
 172 struct ccp_des3_def {
 173         enum ccp_des3_mode mode;
 174         unsigned int version;
 175         const char *name;
 176         const char *driver_name;
 177         unsigned int blocksize;
 178         unsigned int ivsize;
 179         struct crypto_alg *alg_defaults;
 180 };
 181
 182 static struct ccp_des3_def des3_algs[] = {
 183         {
 184                 .mode           = CCP_DES3_MODE_ECB,
 185                 .version        = CCP_VERSION(5, 0),
 186                 .name           = "ecb(des3_ede)",
 187                 .driver_name    = "ecb-des3-ccp",
 188                 .blocksize      = DES3_EDE_BLOCK_SIZE,
 189                 .ivsize         = 0,
 190                 .alg_defaults   = &ccp_des3_defaults,
 191         },
 192         {
 193                 .mode           = CCP_DES3_MODE_CBC,
 194                 .version        = CCP_VERSION(5, 0),
 195                 .name           = "cbc(des3_ede)",
 196                 .driver_name    = "cbc-des3-ccp",
 197                 .blocksize      = DES3_EDE_BLOCK_SIZE,
 198                 .ivsize         = DES3_EDE_BLOCK_SIZE,
 199                 .alg_defaults   = &ccp_des3_defaults,
 200         },
 201 };
 202
 203 static int ccp_register_des3_alg(struct list_head *head,
 204                                  const struct ccp_des3_def *def)
 205 {
 206         struct ccp_crypto_ablkcipher_alg *ccp_alg;
 207         struct crypto_alg *alg;
 208         int ret;
 209
 210         ccp_alg = kzalloc(sizeof(*ccp_alg), GFP_KERNEL);
 211         if (!ccp_alg)
 212                 return -ENOMEM;
 213
 214         INIT_LIST_HEAD(&ccp_alg->entry);
 215
 216         ccp_alg->mode = def->mode;
 217
 218         /* Copy the defaults and override as necessary */
 219         alg = &ccp_alg->alg;
 220         *alg = *def->alg_defaults;
 221         snprintf(alg->cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
 222         snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 223                         def->driver_name);
 224         alg->cra_blocksize = def->blocksize;
 225         alg->cra_ablkcipher.ivsize = def->ivsize;
 226
 227         ret = crypto_register_alg(alg);
 228         if (ret) {
 229                 pr_err("%s ablkcipher algorithm registration error (%d)\n",
 230                                 alg->cra_name, ret);
 231                 kfree(ccp_alg);
 232                 return ret;
 233         }
 234
 235         list_add(&ccp_alg->entry, head);
 236
 237         return 0;
 238 }
 239
 240 int ccp_register_des3_algs(struct list_head *head)
 241 {
 242         int i, ret;
 243         unsigned int ccpversion = ccp_version();
 244
 245         for (i = 0; i < ARRAY_SIZE(des3_algs); i++) {
 246                 if (des3_algs[i].version > ccpversion)
 247                         continue;
 248                 ret = ccp_register_des3_alg(head, &des3_algs[i]);
 249                 if (ret)
 250                         return ret;
 251         }
 252
 253         return 0;
 254 }