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// SPDX-License-Identifier: GPL-2.0-only
/*
* AMD Cryptographic Coprocessor (CCP) AES GCM crypto API support
*
* Copyright (C) 2016,2017 Advanced Micro Devices, Inc.
*
* Author: Gary R Hook <gary.hook@amd.com>
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <linux/crypto.h>
#include <crypto/internal/aead.h>
#include <crypto/algapi.h>
#include <crypto/aes.h>
#include <crypto/ctr.h>
#include <crypto/gcm.h>
#include <crypto/scatterwalk.h>
#include "ccp-crypto.h"
static int ccp_aes_gcm_complete(struct crypto_async_request *async_req, int ret)
{
return ret;
}
static int ccp_aes_gcm_setkey(struct crypto_aead *tfm, const u8 *key,
unsigned int key_len)
{
struct ccp_ctx *ctx = crypto_aead_ctx_dma(tfm);
switch (key_len) {
case AES_KEYSIZE_128:
ctx->u.aes.type = CCP_AES_TYPE_128;
break;
case AES_KEYSIZE_192:
ctx->u.aes.type = CCP_AES_TYPE_192;
break;
case AES_KEYSIZE_256:
ctx->u.aes.type = CCP_AES_TYPE_256;
break;
default:
return -EINVAL;
}
ctx->u.aes.mode = CCP_AES_MODE_GCM;
ctx->u.aes.key_len = key_len;
memcpy(ctx->u.aes.key, key, key_len);
sg_init_one(&ctx->u.aes.key_sg, ctx->u.aes.key, key_len);
return 0;
}
static int ccp_aes_gcm_setauthsize(struct crypto_aead *tfm,
unsigned int authsize)
{
switch (authsize) {
case 16:
case 15:
case 14:
case 13:
case 12:
case 8:
case 4:
break;
default:
return -EINVAL;
}
return 0;
}
static int ccp_aes_gcm_crypt(struct aead_request *req, bool encrypt)
{
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
struct ccp_ctx *ctx = crypto_aead_ctx_dma(tfm);
struct ccp_aes_req_ctx *rctx = aead_request_ctx_dma(req);
struct scatterlist *iv_sg = NULL;
unsigned int iv_len = 0;
int i;
int ret = 0;
if (!ctx->u.aes.key_len)
return -EINVAL;
if (ctx->u.aes.mode != CCP_AES_MODE_GCM)
return -EINVAL;
if (!req->iv)
return -EINVAL;
/*
* 5 parts:
* plaintext/ciphertext input
* AAD
* key
* IV
* Destination+tag buffer
*/
/* Prepare the IV: 12 bytes + an integer (counter) */
memcpy(rctx->iv, req->iv, GCM_AES_IV_SIZE);
for (i = 0; i < 3; i++)
rctx->iv[i + GCM_AES_IV_SIZE] = 0;
rctx->iv[AES_BLOCK_SIZE - 1] = 1;
/* Set up a scatterlist for the IV */
iv_sg = &rctx->iv_sg;
iv_len = AES_BLOCK_SIZE;
sg_init_one(iv_sg, rctx->iv, iv_len);
/* The AAD + plaintext are concatenated in the src buffer */
memset(&rctx->cmd, 0, sizeof(rctx->cmd));
INIT_LIST_HEAD(&rctx->cmd.entry);
rctx->cmd.engine = CCP_ENGINE_AES;
rctx->cmd.u.aes.authsize = crypto_aead_authsize(tfm);
rctx->cmd.u.aes.type = ctx->u.aes.type;
rctx->cmd.u.aes.mode = ctx->u.aes.mode;
rctx->cmd.u.aes.action = encrypt;
rctx->cmd.u.aes.key = &ctx->u.aes.key_sg;
rctx->cmd.u.aes.key_len = ctx->u.aes.key_len;
rctx->cmd.u.aes.iv = iv_sg;
rctx->cmd.u.aes.iv_len = iv_len;
rctx->cmd.u.aes.src = req->src;
rctx->cmd.u.aes.src_len = req->cryptlen;
rctx->cmd.u.aes.aad_len = req->assoclen;
/* The cipher text + the tag are in the dst buffer */
rctx->cmd.u.aes.dst = req->dst;
ret = ccp_crypto_enqueue_request(&req->base, &rctx->cmd);
return ret;
}
static int ccp_aes_gcm_encrypt(struct aead_request *req)
{
return ccp_aes_gcm_crypt(req, CCP_AES_ACTION_ENCRYPT);
}
static int ccp_aes_gcm_decrypt(struct aead_request *req)
{
return ccp_aes_gcm_crypt(req, CCP_AES_ACTION_DECRYPT);
}
static int ccp_aes_gcm_cra_init(struct crypto_aead *tfm)
{
struct ccp_ctx *ctx = crypto_aead_ctx_dma(tfm);
ctx->complete = ccp_aes_gcm_complete;
ctx->u.aes.key_len = 0;
crypto_aead_set_reqsize_dma(tfm, sizeof(struct ccp_aes_req_ctx));
return 0;
}
static void ccp_aes_gcm_cra_exit(struct crypto_tfm *tfm)
{
}
static struct aead_alg ccp_aes_gcm_defaults = {
.setkey = ccp_aes_gcm_setkey,
.setauthsize = ccp_aes_gcm_setauthsize,
.encrypt = ccp_aes_gcm_encrypt,
.decrypt = ccp_aes_gcm_decrypt,
.init = ccp_aes_gcm_cra_init,
.ivsize = GCM_AES_IV_SIZE,
.maxauthsize = AES_BLOCK_SIZE,
.base = {
.cra_flags = CRYPTO_ALG_ASYNC |
CRYPTO_ALG_ALLOCATES_MEMORY |
CRYPTO_ALG_KERN_DRIVER_ONLY |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct ccp_ctx) + CRYPTO_DMA_PADDING,
.cra_priority = CCP_CRA_PRIORITY,
.cra_exit = ccp_aes_gcm_cra_exit,
.cra_module = THIS_MODULE,
},
};
struct ccp_aes_aead_def {
enum ccp_aes_mode mode;
unsigned int version;
const char *name;
const char *driver_name;
unsigned int blocksize;
unsigned int ivsize;
struct aead_alg *alg_defaults;
};
static struct ccp_aes_aead_def aes_aead_algs[] = {
{
.mode = CCP_AES_MODE_GHASH,
.version = CCP_VERSION(5, 0),
.name = "gcm(aes)",
.driver_name = "gcm-aes-ccp",
.blocksize = 1,
.ivsize = AES_BLOCK_SIZE,
.alg_defaults = &ccp_aes_gcm_defaults,
},
};
static int ccp_register_aes_aead(struct list_head *head,
const struct ccp_aes_aead_def *def)
{
struct ccp_crypto_aead *ccp_aead;
struct aead_alg *alg;
int ret;
ccp_aead = kzalloc(sizeof(*ccp_aead), GFP_KERNEL);
if (!ccp_aead)
return -ENOMEM;
INIT_LIST_HEAD(&ccp_aead->entry);
ccp_aead->mode = def->mode;
/* Copy the defaults and override as necessary */
alg = &ccp_aead->alg;
*alg = *def->alg_defaults;
snprintf(alg->base.cra_name, CRYPTO_MAX_ALG_NAME, "%s", def->name);
snprintf(alg->base.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
def->driver_name);
alg->base.cra_blocksize = def->blocksize;
ret = crypto_register_aead(alg);
if (ret) {
pr_err("%s aead algorithm registration error (%d)\n",
alg->base.cra_name, ret);
kfree(ccp_aead);
return ret;
}
list_add(&ccp_aead->entry, head);
return 0;
}
int ccp_register_aes_aeads(struct list_head *head)
{
int i, ret;
unsigned int ccpversion = ccp_version();
for (i = 0; i < ARRAY_SIZE(aes_aead_algs); i++) {
if (aes_aead_algs[i].version > ccpversion)
continue;
ret = ccp_register_aes_aead(head, &aes_aead_algs[i]);
if (ret)
return ret;
}
return 0;
}