static int ccm_encrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_aes_ctx *ctx = crypto_aead_ctx(aead);
struct blkcipher_desc desc = { .info = req->iv };
struct blkcipher_walk walk;
struct scatterlist srcbuf[2];
struct scatterlist dstbuf[2];
struct scatterlist *src;
struct scatterlist *dst;
u8 __aligned(8) mac[AES_BLOCK_SIZE];
u8 buf[AES_BLOCK_SIZE];
u32 len = req->cryptlen;
int err;
err = ccm_init_mac(req, mac, len);
if (err)
return err;
kernel_neon_begin_partial(6);
if (req->assoclen)
ccm_calculate_auth_mac(req, mac);
/* preserve the original iv for the final round */
memcpy(buf, req->iv, AES_BLOCK_SIZE);
src = scatterwalk_ffwd(srcbuf, req->src, req->assoclen);
dst = src;
if (req->src != req->dst)
dst = scatterwalk_ffwd(dstbuf, req->dst, req->assoclen);
blkcipher_walk_init(&walk, dst, src, len);
err = blkcipher_aead_walk_virt_block(&desc, &walk, aead,
AES_BLOCK_SIZE);
while (walk.nbytes) {
u32 tail = walk.nbytes % AES_BLOCK_SIZE;
if (walk.nbytes == len)
tail = 0;
ce_aes_ccm_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
walk.nbytes - tail, ctx->key_enc,
num_rounds(ctx), mac, walk.iv);
len -= walk.nbytes - tail;
err = blkcipher_walk_done(&desc, &walk, tail);
}
if (!err)
ce_aes_ccm_final(mac, buf, ctx->key_enc, num_rounds(ctx));
kernel_neon_end();
if (err)
return err;
/* copy authtag to end of dst */
scatterwalk_map_and_copy(mac, dst, req->cryptlen,
crypto_aead_authsize(aead), 1);
return 0;
}
static int ccm_decrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_aes_ctx *ctx = crypto_aead_ctx(aead);
unsigned int authsize = crypto_aead_authsize(aead);
struct blkcipher_desc desc = { .info = req->iv };
struct blkcipher_walk walk;
struct scatterlist srcbuf[2];
struct scatterlist dstbuf[2];
struct scatterlist *src;
struct scatterlist *dst;
u8 __aligned(8) mac[AES_BLOCK_SIZE];
u8 buf[AES_BLOCK_SIZE];
u32 len = req->cryptlen - authsize;
int err;
err = ccm_init_mac(req, mac, len);
if (err)
return err;
kernel_neon_begin_partial(6);
if (req->assoclen)
ccm_calculate_auth_mac(req, mac);
/* preserve the original iv for the final round */
memcpy(buf, req->iv, AES_BLOCK_SIZE);
src = scatterwalk_ffwd(srcbuf, req->src, req->assoclen);
dst = src;
if (req->src != req->dst)
dst = scatterwalk_ffwd(dstbuf, req->dst, req->assoclen);
blkcipher_walk_init(&walk, dst, src, len);
err = blkcipher_aead_walk_virt_block(&desc, &walk, aead,
AES_BLOCK_SIZE);
while (walk.nbytes) {
u32 tail = walk.nbytes % AES_BLOCK_SIZE;
if (walk.nbytes == len)
tail = 0;
ce_aes_ccm_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
walk.nbytes - tail, ctx->key_enc,
num_rounds(ctx), mac, walk.iv);
len -= walk.nbytes - tail;
err = blkcipher_walk_done(&desc, &walk, tail);
}
if (!err)
ce_aes_ccm_final(mac, buf, ctx->key_enc, num_rounds(ctx));
kernel_neon_end();
if (err)
return err;
/* compare calculated auth tag with the stored one */
scatterwalk_map_and_copy(buf, src, req->cryptlen - authsize,
authsize, 0);
if (crypto_memneq(mac, buf, authsize))
return -EBADMSG;
return 0;
}
static struct aead_alg ccm_aes_alg = {
.base = {
.cra_name = "ccm(aes)",
.cra_driver_name = "ccm-aes-ce",
.cra_flags = CRYPTO_ALG_AEAD_NEW,
.cra_priority = 300,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct crypto_aes_ctx),
.cra_alignmask = 7,
.cra_module = THIS_MODULE,
},
.ivsize = AES_BLOCK_SIZE,
.maxauthsize = AES_BLOCK_SIZE,
.setkey = ccm_setkey,
.setauthsize = ccm_setauthsize,
.encrypt = ccm_encrypt,
.decrypt = ccm_decrypt,
};
static int __init aes_mod_init(void)
{
if (!(elf_hwcap & HWCAP_AES))
return -ENODEV;
return crypto_register_aead(&ccm_aes_alg);
}
static void __exit aes_mod_exit(void)
{
crypto_unregister_aead(&ccm_aes_alg);
}
static int ccm_decrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_aes_ctx *ctx = crypto_aead_ctx(aead);
unsigned int authsize = crypto_aead_authsize(aead);
struct skcipher_walk walk;
u8 __aligned(8) mac[AES_BLOCK_SIZE];
u8 buf[AES_BLOCK_SIZE];
u32 len = req->cryptlen - authsize;
int err;
err = ccm_init_mac(req, mac, len);
if (err)
return err;
if (req->assoclen)
ccm_calculate_auth_mac(req, mac);
/* preserve the original iv for the final round */
memcpy(buf, req->iv, AES_BLOCK_SIZE);
err = skcipher_walk_aead_decrypt(&walk, req, false);
if (crypto_simd_usable()) {
while (walk.nbytes) {
u32 tail = walk.nbytes % AES_BLOCK_SIZE;
if (walk.nbytes == walk.total)
tail = 0;
kernel_neon_begin();
ce_aes_ccm_decrypt(walk.dst.virt.addr,
walk.src.virt.addr,
walk.nbytes - tail, ctx->key_enc,
num_rounds(ctx), mac, walk.iv);
kernel_neon_end();
err = skcipher_walk_done(&walk, tail);
}
if (!err) {
kernel_neon_begin();
ce_aes_ccm_final(mac, buf, ctx->key_enc,
num_rounds(ctx));
kernel_neon_end();
}
} else {
err = ccm_crypt_fallback(&walk, mac, buf, ctx, false);
}
if (err)
return err;
/* compare calculated auth tag with the stored one */
scatterwalk_map_and_copy(buf, req->src,
req->assoclen + req->cryptlen - authsize,
authsize, 0);
if (crypto_memneq(mac, buf, authsize))
return -EBADMSG;
return 0;
}
