summaryrefslogtreecommitdiffstats
path: root/arch/arm/crypto/aesbs-glue.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/crypto/aesbs-glue.c')
-rw-r--r--arch/arm/crypto/aesbs-glue.c434
1 files changed, 434 insertions, 0 deletions
diff --git a/arch/arm/crypto/aesbs-glue.c b/arch/arm/crypto/aesbs-glue.c
new file mode 100644
index 000000000000..4522366da759
--- /dev/null
+++ b/arch/arm/crypto/aesbs-glue.c
@@ -0,0 +1,434 @@
+/*
+ * linux/arch/arm/crypto/aesbs-glue.c - glue code for NEON bit sliced AES
+ *
+ * Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <asm/neon.h>
+#include <crypto/aes.h>
+#include <crypto/ablk_helper.h>
+#include <crypto/algapi.h>
+#include <linux/module.h>
+
+#include "aes_glue.h"
+
+#define BIT_SLICED_KEY_MAXSIZE (128 * (AES_MAXNR - 1) + 2 * AES_BLOCK_SIZE)
+
+struct BS_KEY {
+ struct AES_KEY rk;
+ int converted;
+ u8 __aligned(8) bs[BIT_SLICED_KEY_MAXSIZE];
+} __aligned(8);
+
+asmlinkage void bsaes_enc_key_convert(u8 out[], struct AES_KEY const *in);
+asmlinkage void bsaes_dec_key_convert(u8 out[], struct AES_KEY const *in);
+
+asmlinkage void bsaes_cbc_encrypt(u8 const in[], u8 out[], u32 bytes,
+ struct BS_KEY *key, u8 iv[]);
+
+asmlinkage void bsaes_ctr32_encrypt_blocks(u8 const in[], u8 out[], u32 blocks,
+ struct BS_KEY *key, u8 const iv[]);
+
+asmlinkage void bsaes_xts_encrypt(u8 const in[], u8 out[], u32 bytes,
+ struct BS_KEY *key, u8 tweak[]);
+
+asmlinkage void bsaes_xts_decrypt(u8 const in[], u8 out[], u32 bytes,
+ struct BS_KEY *key, u8 tweak[]);
+
+struct aesbs_cbc_ctx {
+ struct AES_KEY enc;
+ struct BS_KEY dec;
+};
+
+struct aesbs_ctr_ctx {
+ struct BS_KEY enc;
+};
+
+struct aesbs_xts_ctx {
+ struct BS_KEY enc;
+ struct BS_KEY dec;
+ struct AES_KEY twkey;
+};
+
+static int aesbs_cbc_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+ unsigned int key_len)
+{
+ struct aesbs_cbc_ctx *ctx = crypto_tfm_ctx(tfm);
+ int bits = key_len * 8;
+
+ if (private_AES_set_encrypt_key(in_key, bits, &ctx->enc)) {
+ tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+ ctx->dec.rk = ctx->enc;
+ private_AES_set_decrypt_key(in_key, bits, &ctx->dec.rk);
+ ctx->dec.converted = 0;
+ return 0;
+}
+
+static int aesbs_ctr_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+ unsigned int key_len)
+{
+ struct aesbs_ctr_ctx *ctx = crypto_tfm_ctx(tfm);
+ int bits = key_len * 8;
+
+ if (private_AES_set_encrypt_key(in_key, bits, &ctx->enc.rk)) {
+ tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+ ctx->enc.converted = 0;
+ return 0;
+}
+
+static int aesbs_xts_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+ unsigned int key_len)
+{
+ struct aesbs_xts_ctx *ctx = crypto_tfm_ctx(tfm);
+ int bits = key_len * 4;
+
+ if (private_AES_set_encrypt_key(in_key, bits, &ctx->enc.rk)) {
+ tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+ return -EINVAL;
+ }
+ ctx->dec.rk = ctx->enc.rk;
+ private_AES_set_decrypt_key(in_key, bits, &ctx->dec.rk);
+ private_AES_set_encrypt_key(in_key + key_len / 2, bits, &ctx->twkey);
+ ctx->enc.converted = ctx->dec.converted = 0;
+ return 0;
+}
+
+static int aesbs_cbc_encrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes)
+{
+ struct aesbs_cbc_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+ struct blkcipher_walk walk;
+ int err;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ err = blkcipher_walk_virt(desc, &walk);
+
+ while (walk.nbytes) {
+ u32 blocks = walk.nbytes / AES_BLOCK_SIZE;
+ u8 *src = walk.src.virt.addr;
+
+ if (walk.dst.virt.addr == walk.src.virt.addr) {
+ u8 *iv = walk.iv;
+
+ do {
+ crypto_xor(src, iv, AES_BLOCK_SIZE);
+ AES_encrypt(src, src, &ctx->enc);
+ iv = src;
+ src += AES_BLOCK_SIZE;
+ } while (--blocks);
+ memcpy(walk.iv, iv, AES_BLOCK_SIZE);
+ } else {
+ u8 *dst = walk.dst.virt.addr;
+
+ do {
+ crypto_xor(walk.iv, src, AES_BLOCK_SIZE);
+ AES_encrypt(walk.iv, dst, &ctx->enc);
+ memcpy(walk.iv, dst, AES_BLOCK_SIZE);
+ src += AES_BLOCK_SIZE;
+ dst += AES_BLOCK_SIZE;
+ } while (--blocks);
+ }
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+ return err;
+}
+
+static int aesbs_cbc_decrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes)
+{
+ struct aesbs_cbc_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+ struct blkcipher_walk walk;
+ int err;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ err = blkcipher_walk_virt_block(desc, &walk, 8 * AES_BLOCK_SIZE);
+
+ while ((walk.nbytes / AES_BLOCK_SIZE) >= 8) {
+ kernel_neon_begin();
+ bsaes_cbc_encrypt(walk.src.virt.addr, walk.dst.virt.addr,
+ walk.nbytes, &ctx->dec, walk.iv);
+ kernel_neon_end();
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+ while (walk.nbytes) {
+ u32 blocks = walk.nbytes / AES_BLOCK_SIZE;
+ u8 *dst = walk.dst.virt.addr;
+ u8 *src = walk.src.virt.addr;
+ u8 bk[2][AES_BLOCK_SIZE];
+ u8 *iv = walk.iv;
+
+ do {
+ if (walk.dst.virt.addr == walk.src.virt.addr)
+ memcpy(bk[blocks & 1], src, AES_BLOCK_SIZE);
+
+ AES_decrypt(src, dst, &ctx->dec.rk);
+ crypto_xor(dst, iv, AES_BLOCK_SIZE);
+
+ if (walk.dst.virt.addr == walk.src.virt.addr)
+ iv = bk[blocks & 1];
+ else
+ iv = src;
+
+ dst += AES_BLOCK_SIZE;
+ src += AES_BLOCK_SIZE;
+ } while (--blocks);
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+ return err;
+}
+
+static void inc_be128_ctr(__be32 ctr[], u32 addend)
+{
+ int i;
+
+ for (i = 3; i >= 0; i--, addend = 1) {
+ u32 n = be32_to_cpu(ctr[i]) + addend;
+
+ ctr[i] = cpu_to_be32(n);
+ if (n >= addend)
+ break;
+ }
+}
+
+static int aesbs_ctr_encrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst, struct scatterlist *src,
+ unsigned int nbytes)
+{
+ struct aesbs_ctr_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+ struct blkcipher_walk walk;
+ u32 blocks;
+ int err;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ err = blkcipher_walk_virt_block(desc, &walk, 8 * AES_BLOCK_SIZE);
+
+ while ((blocks = walk.nbytes / AES_BLOCK_SIZE)) {
+ u32 tail = walk.nbytes % AES_BLOCK_SIZE;
+ __be32 *ctr = (__be32 *)walk.iv;
+ u32 headroom = UINT_MAX - be32_to_cpu(ctr[3]);
+
+ /* avoid 32 bit counter overflow in the NEON code */
+ if (unlikely(headroom < blocks)) {
+ blocks = headroom + 1;
+ tail = walk.nbytes - blocks * AES_BLOCK_SIZE;
+ }
+ kernel_neon_begin();
+ bsaes_ctr32_encrypt_blocks(walk.src.virt.addr,
+ walk.dst.virt.addr, blocks,
+ &ctx->enc, walk.iv);
+ kernel_neon_end();
+ inc_be128_ctr(ctr, blocks);
+
+ nbytes -= blocks * AES_BLOCK_SIZE;
+ if (nbytes && nbytes == tail && nbytes <= AES_BLOCK_SIZE)
+ break;
+
+ err = blkcipher_walk_done(desc, &walk, tail);
+ }
+ if (walk.nbytes) {
+ u8 *tdst = walk.dst.virt.addr + blocks * AES_BLOCK_SIZE;
+ u8 *tsrc = walk.src.virt.addr + blocks * AES_BLOCK_SIZE;
+ u8 ks[AES_BLOCK_SIZE];
+
+ AES_encrypt(walk.iv, ks, &ctx->enc.rk);
+ if (tdst != tsrc)
+ memcpy(tdst, tsrc, nbytes);
+ crypto_xor(tdst, ks, nbytes);
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+ return err;
+}
+
+static int aesbs_xts_encrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes)
+{
+ struct aesbs_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+ struct blkcipher_walk walk;
+ int err;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ err = blkcipher_walk_virt_block(desc, &walk, 8 * AES_BLOCK_SIZE);
+
+ /* generate the initial tweak */
+ AES_encrypt(walk.iv, walk.iv, &ctx->twkey);
+
+ while (walk.nbytes) {
+ kernel_neon_begin();
+ bsaes_xts_encrypt(walk.src.virt.addr, walk.dst.virt.addr,
+ walk.nbytes, &ctx->enc, walk.iv);
+ kernel_neon_end();
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+ return err;
+}
+
+static int aesbs_xts_decrypt(struct blkcipher_desc *desc,
+ struct scatterlist *dst,
+ struct scatterlist *src, unsigned int nbytes)
+{
+ struct aesbs_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
+ struct blkcipher_walk walk;
+ int err;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ err = blkcipher_walk_virt_block(desc, &walk, 8 * AES_BLOCK_SIZE);
+
+ /* generate the initial tweak */
+ AES_encrypt(walk.iv, walk.iv, &ctx->twkey);
+
+ while (walk.nbytes) {
+ kernel_neon_begin();
+ bsaes_xts_decrypt(walk.src.virt.addr, walk.dst.virt.addr,
+ walk.nbytes, &ctx->dec, walk.iv);
+ kernel_neon_end();
+ err = blkcipher_walk_done(desc, &walk, 0);
+ }
+ return err;
+}
+
+static struct crypto_alg aesbs_algs[] = { {
+ .cra_name = "__cbc-aes-neonbs",
+ .cra_driver_name = "__driver-cbc-aes-neonbs",
+ .cra_priority = 0,
+ .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct aesbs_cbc_ctx),
+ .cra_alignmask = 7,
+ .cra_type = &crypto_blkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_blkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = aesbs_cbc_set_key,
+ .encrypt = aesbs_cbc_encrypt,
+ .decrypt = aesbs_cbc_decrypt,
+ },
+}, {
+ .cra_name = "__ctr-aes-neonbs",
+ .cra_driver_name = "__driver-ctr-aes-neonbs",
+ .cra_priority = 0,
+ .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
+ .cra_blocksize = 1,
+ .cra_ctxsize = sizeof(struct aesbs_ctr_ctx),
+ .cra_alignmask = 7,
+ .cra_type = &crypto_blkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_blkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = aesbs_ctr_set_key,
+ .encrypt = aesbs_ctr_encrypt,
+ .decrypt = aesbs_ctr_encrypt,
+ },
+}, {
+ .cra_name = "__xts-aes-neonbs",
+ .cra_driver_name = "__driver-xts-aes-neonbs",
+ .cra_priority = 0,
+ .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct aesbs_xts_ctx),
+ .cra_alignmask = 7,
+ .cra_type = &crypto_blkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_blkcipher = {
+ .min_keysize = 2 * AES_MIN_KEY_SIZE,
+ .max_keysize = 2 * AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = aesbs_xts_set_key,
+ .encrypt = aesbs_xts_encrypt,
+ .decrypt = aesbs_xts_decrypt,
+ },
+}, {
+ .cra_name = "cbc(aes)",
+ .cra_driver_name = "cbc-aes-neonbs",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct async_helper_ctx),
+ .cra_alignmask = 7,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = ablk_init,
+ .cra_exit = ablk_exit,
+ .cra_ablkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = ablk_set_key,
+ .encrypt = __ablk_encrypt,
+ .decrypt = ablk_decrypt,
+ }
+}, {
+ .cra_name = "ctr(aes)",
+ .cra_driver_name = "ctr-aes-neonbs",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
+ .cra_blocksize = 1,
+ .cra_ctxsize = sizeof(struct async_helper_ctx),
+ .cra_alignmask = 7,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = ablk_init,
+ .cra_exit = ablk_exit,
+ .cra_ablkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = ablk_set_key,
+ .encrypt = ablk_encrypt,
+ .decrypt = ablk_decrypt,
+ }
+}, {
+ .cra_name = "xts(aes)",
+ .cra_driver_name = "xts-aes-neonbs",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct async_helper_ctx),
+ .cra_alignmask = 7,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = ablk_init,
+ .cra_exit = ablk_exit,
+ .cra_ablkcipher = {
+ .min_keysize = 2 * AES_MIN_KEY_SIZE,
+ .max_keysize = 2 * AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = ablk_set_key,
+ .encrypt = ablk_encrypt,
+ .decrypt = ablk_decrypt,
+ }
+} };
+
+static int __init aesbs_mod_init(void)
+{
+ if (!cpu_has_neon())
+ return -ENODEV;
+
+ return crypto_register_algs(aesbs_algs, ARRAY_SIZE(aesbs_algs));
+}
+
+static void __exit aesbs_mod_exit(void)
+{
+ crypto_unregister_algs(aesbs_algs, ARRAY_SIZE(aesbs_algs));
+}
+
+module_init(aesbs_mod_init);
+module_exit(aesbs_mod_exit);
+
+MODULE_DESCRIPTION("Bit sliced AES in CBC/CTR/XTS modes using NEON");
+MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
+MODULE_LICENSE("GPL");