Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/**
 * AES CTR routines supporting VMX instructions on the Power 8
 *
 * Copyright (C) 2015 International Business Machines Inc.
 *
 * Author: Marcelo Henrique Cerri <mhcerri@br.ibm.com>
 */
 
#include <asm/simd.h>
#include <asm/switch_to.h>
#include <crypto/aes.h>
#include <crypto/internal/simd.h>
#include <crypto/internal/skcipher.h>
 
#include "aesp8-ppc.h"
 
struct p8_aes_ctr_ctx {
<------>struct crypto_skcipher *fallback;
<------>struct aes_key enc_key;
};
 
static int p8_aes_ctr_init(struct crypto_skcipher *tfm)
{
<------>struct p8_aes_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
<------>struct crypto_skcipher *fallback;
 
<------>fallback = crypto_alloc_skcipher("ctr(aes)", 0,
<------><------><------><------><------> CRYPTO_ALG_NEED_FALLBACK |
<------><------><------><------><------> CRYPTO_ALG_ASYNC);
<------>if (IS_ERR(fallback)) {
<------><------>pr_err("Failed to allocate ctr(aes) fallback: %ld\n",
<------><------>       PTR_ERR(fallback));
<------><------>return PTR_ERR(fallback);
<------>}
 
<------>crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
<------><------><------><------>    crypto_skcipher_reqsize(fallback));
<------>ctx->fallback = fallback;
<------>return 0;
}
 
static void p8_aes_ctr_exit(struct crypto_skcipher *tfm)
{
<------>struct p8_aes_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
 
<------>crypto_free_skcipher(ctx->fallback);
}
 
static int p8_aes_ctr_setkey(struct crypto_skcipher *tfm, const u8 *key,
<------><------><------>     unsigned int keylen)
{
<------>struct p8_aes_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
<------>int ret;
 
<------>preempt_disable();
<------>pagefault_disable();
<------>enable_kernel_vsx();
<------>ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key);
<------>disable_kernel_vsx();
<------>pagefault_enable();
<------>preempt_enable();
 
<------>ret |= crypto_skcipher_setkey(ctx->fallback, key, keylen);
 
<------>return ret ? -EINVAL : 0;
}
 
static void p8_aes_ctr_final(const struct p8_aes_ctr_ctx *ctx,
<------><------><------>     struct skcipher_walk *walk)
{
<------>u8 *ctrblk = walk->iv;
<------>u8 keystream[AES_BLOCK_SIZE];
<------>u8 *src = walk->src.virt.addr;
<------>u8 *dst = walk->dst.virt.addr;
<------>unsigned int nbytes = walk->nbytes;
 
<------>preempt_disable();
<------>pagefault_disable();
<------>enable_kernel_vsx();
<------>aes_p8_encrypt(ctrblk, keystream, &ctx->enc_key);
<------>disable_kernel_vsx();
<------>pagefault_enable();
<------>preempt_enable();
 
<------>crypto_xor_cpy(dst, keystream, src, nbytes);
<------>crypto_inc(ctrblk, AES_BLOCK_SIZE);
}
 
static int p8_aes_ctr_crypt(struct skcipher_request *req)
{
<------>struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
<------>const struct p8_aes_ctr_ctx *ctx = crypto_skcipher_ctx(tfm);
<------>struct skcipher_walk walk;
<------>unsigned int nbytes;
<------>int ret;
 
<------>if (!crypto_simd_usable()) {
<------><------>struct skcipher_request *subreq = skcipher_request_ctx(req);
 
<------><------>*subreq = *req;
<------><------>skcipher_request_set_tfm(subreq, ctx->fallback);
<------><------>return crypto_skcipher_encrypt(subreq);
<------>}
 
<------>ret = skcipher_walk_virt(&walk, req, false);
<------>while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
<------><------>preempt_disable();
<------><------>pagefault_disable();
<------><------>enable_kernel_vsx();
<------><------>aes_p8_ctr32_encrypt_blocks(walk.src.virt.addr,
<------><------><------><------><------>    walk.dst.virt.addr,
<------><------><------><------><------>    nbytes / AES_BLOCK_SIZE,
<------><------><------><------><------>    &ctx->enc_key, walk.iv);
<------><------>disable_kernel_vsx();
<------><------>pagefault_enable();
<------><------>preempt_enable();
 
<------><------>do {
<------><------><------>crypto_inc(walk.iv, AES_BLOCK_SIZE);
<------><------>} while ((nbytes -= AES_BLOCK_SIZE) >= AES_BLOCK_SIZE);
 
<------><------>ret = skcipher_walk_done(&walk, nbytes);
<------>}
<------>if (nbytes) {
<------><------>p8_aes_ctr_final(ctx, &walk);
<------><------>ret = skcipher_walk_done(&walk, 0);
<------>}
<------>return ret;
}
 
struct skcipher_alg p8_aes_ctr_alg = {
<------>.base.cra_name = "ctr(aes)",
<------>.base.cra_driver_name = "p8_aes_ctr",
<------>.base.cra_module = THIS_MODULE,
<------>.base.cra_priority = 2000,
<------>.base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
<------>.base.cra_blocksize = 1,
<------>.base.cra_ctxsize = sizeof(struct p8_aes_ctr_ctx),
<------>.setkey = p8_aes_ctr_setkey,
<------>.encrypt = p8_aes_ctr_crypt,
<------>.decrypt = p8_aes_ctr_crypt,
<------>.init = p8_aes_ctr_init,
<------>.exit = p8_aes_ctr_exit,
<------>.min_keysize = AES_MIN_KEY_SIZE,
<------>.max_keysize = AES_MAX_KEY_SIZE,
<------>.ivsize = AES_BLOCK_SIZE,
<------>.chunksize = AES_BLOCK_SIZE,
};