| /* |
| * Cryptographic API. |
| * |
| * s390 implementation of the AES Cipher Algorithm. |
| * |
| * s390 Version: |
| * Copyright IBM Corp. 2005,2007 |
| * Author(s): Jan Glauber (jang@de.ibm.com) |
| * Sebastian Siewior (sebastian@breakpoint.cc> SW-Fallback |
| * |
| * Derived from "crypto/aes_generic.c" |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the Free |
| * Software Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| * |
| */ |
| |
| #include <crypto/aes.h> |
| #include <crypto/algapi.h> |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/init.h> |
| #include "crypt_s390.h" |
| |
| #define AES_KEYLEN_128 1 |
| #define AES_KEYLEN_192 2 |
| #define AES_KEYLEN_256 4 |
| |
| static char keylen_flag = 0; |
| |
| struct s390_aes_ctx { |
| u8 iv[AES_BLOCK_SIZE]; |
| u8 key[AES_MAX_KEY_SIZE]; |
| long enc; |
| long dec; |
| int key_len; |
| union { |
| struct crypto_blkcipher *blk; |
| struct crypto_cipher *cip; |
| } fallback; |
| }; |
| |
| /* |
| * Check if the key_len is supported by the HW. |
| * Returns 0 if it is, a positive number if it is not and software fallback is |
| * required or a negative number in case the key size is not valid |
| */ |
| static int need_fallback(unsigned int key_len) |
| { |
| switch (key_len) { |
| case 16: |
| if (!(keylen_flag & AES_KEYLEN_128)) |
| return 1; |
| break; |
| case 24: |
| if (!(keylen_flag & AES_KEYLEN_192)) |
| return 1; |
| break; |
| case 32: |
| if (!(keylen_flag & AES_KEYLEN_256)) |
| return 1; |
| break; |
| default: |
| return -1; |
| break; |
| } |
| return 0; |
| } |
| |
| static int setkey_fallback_cip(struct crypto_tfm *tfm, const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| int ret; |
| |
| sctx->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; |
| sctx->fallback.blk->base.crt_flags |= (tfm->crt_flags & |
| CRYPTO_TFM_REQ_MASK); |
| |
| ret = crypto_cipher_setkey(sctx->fallback.cip, in_key, key_len); |
| if (ret) { |
| tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; |
| tfm->crt_flags |= (sctx->fallback.blk->base.crt_flags & |
| CRYPTO_TFM_RES_MASK); |
| } |
| return ret; |
| } |
| |
| static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| u32 *flags = &tfm->crt_flags; |
| int ret; |
| |
| ret = need_fallback(key_len); |
| if (ret < 0) { |
| *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; |
| return -EINVAL; |
| } |
| |
| sctx->key_len = key_len; |
| if (!ret) { |
| memcpy(sctx->key, in_key, key_len); |
| return 0; |
| } |
| |
| return setkey_fallback_cip(tfm, in_key, key_len); |
| } |
| |
| static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) |
| { |
| const struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| |
| if (unlikely(need_fallback(sctx->key_len))) { |
| crypto_cipher_encrypt_one(sctx->fallback.cip, out, in); |
| return; |
| } |
| |
| switch (sctx->key_len) { |
| case 16: |
| crypt_s390_km(KM_AES_128_ENCRYPT, &sctx->key, out, in, |
| AES_BLOCK_SIZE); |
| break; |
| case 24: |
| crypt_s390_km(KM_AES_192_ENCRYPT, &sctx->key, out, in, |
| AES_BLOCK_SIZE); |
| break; |
| case 32: |
| crypt_s390_km(KM_AES_256_ENCRYPT, &sctx->key, out, in, |
| AES_BLOCK_SIZE); |
| break; |
| } |
| } |
| |
| static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) |
| { |
| const struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| |
| if (unlikely(need_fallback(sctx->key_len))) { |
| crypto_cipher_decrypt_one(sctx->fallback.cip, out, in); |
| return; |
| } |
| |
| switch (sctx->key_len) { |
| case 16: |
| crypt_s390_km(KM_AES_128_DECRYPT, &sctx->key, out, in, |
| AES_BLOCK_SIZE); |
| break; |
| case 24: |
| crypt_s390_km(KM_AES_192_DECRYPT, &sctx->key, out, in, |
| AES_BLOCK_SIZE); |
| break; |
| case 32: |
| crypt_s390_km(KM_AES_256_DECRYPT, &sctx->key, out, in, |
| AES_BLOCK_SIZE); |
| break; |
| } |
| } |
| |
| static int fallback_init_cip(struct crypto_tfm *tfm) |
| { |
| const char *name = tfm->__crt_alg->cra_name; |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| |
| sctx->fallback.cip = crypto_alloc_cipher(name, 0, |
| CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); |
| |
| if (IS_ERR(sctx->fallback.cip)) { |
| printk(KERN_ERR "Error allocating fallback algo %s\n", name); |
| return PTR_ERR(sctx->fallback.blk); |
| } |
| |
| return 0; |
| } |
| |
| static void fallback_exit_cip(struct crypto_tfm *tfm) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| |
| crypto_free_cipher(sctx->fallback.cip); |
| sctx->fallback.cip = NULL; |
| } |
| |
| static struct crypto_alg aes_alg = { |
| .cra_name = "aes", |
| .cra_driver_name = "aes-s390", |
| .cra_priority = CRYPT_S390_PRIORITY, |
| .cra_flags = CRYPTO_ALG_TYPE_CIPHER | |
| CRYPTO_ALG_NEED_FALLBACK, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct s390_aes_ctx), |
| .cra_module = THIS_MODULE, |
| .cra_list = LIST_HEAD_INIT(aes_alg.cra_list), |
| .cra_init = fallback_init_cip, |
| .cra_exit = fallback_exit_cip, |
| .cra_u = { |
| .cipher = { |
| .cia_min_keysize = AES_MIN_KEY_SIZE, |
| .cia_max_keysize = AES_MAX_KEY_SIZE, |
| .cia_setkey = aes_set_key, |
| .cia_encrypt = aes_encrypt, |
| .cia_decrypt = aes_decrypt, |
| } |
| } |
| }; |
| |
| static int setkey_fallback_blk(struct crypto_tfm *tfm, const u8 *key, |
| unsigned int len) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| unsigned int ret; |
| |
| sctx->fallback.blk->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; |
| sctx->fallback.blk->base.crt_flags |= (tfm->crt_flags & |
| CRYPTO_TFM_REQ_MASK); |
| |
| ret = crypto_blkcipher_setkey(sctx->fallback.blk, key, len); |
| if (ret) { |
| tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; |
| tfm->crt_flags |= (sctx->fallback.blk->base.crt_flags & |
| CRYPTO_TFM_RES_MASK); |
| } |
| return ret; |
| } |
| |
| static int fallback_blk_dec(struct blkcipher_desc *desc, |
| struct scatterlist *dst, struct scatterlist *src, |
| unsigned int nbytes) |
| { |
| unsigned int ret; |
| struct crypto_blkcipher *tfm; |
| struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); |
| |
| tfm = desc->tfm; |
| desc->tfm = sctx->fallback.blk; |
| |
| ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes); |
| |
| desc->tfm = tfm; |
| return ret; |
| } |
| |
| static int fallback_blk_enc(struct blkcipher_desc *desc, |
| struct scatterlist *dst, struct scatterlist *src, |
| unsigned int nbytes) |
| { |
| unsigned int ret; |
| struct crypto_blkcipher *tfm; |
| struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); |
| |
| tfm = desc->tfm; |
| desc->tfm = sctx->fallback.blk; |
| |
| ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes); |
| |
| desc->tfm = tfm; |
| return ret; |
| } |
| |
| static int ecb_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| int ret; |
| |
| ret = need_fallback(key_len); |
| if (ret > 0) { |
| sctx->key_len = key_len; |
| return setkey_fallback_blk(tfm, in_key, key_len); |
| } |
| |
| switch (key_len) { |
| case 16: |
| sctx->enc = KM_AES_128_ENCRYPT; |
| sctx->dec = KM_AES_128_DECRYPT; |
| break; |
| case 24: |
| sctx->enc = KM_AES_192_ENCRYPT; |
| sctx->dec = KM_AES_192_DECRYPT; |
| break; |
| case 32: |
| sctx->enc = KM_AES_256_ENCRYPT; |
| sctx->dec = KM_AES_256_DECRYPT; |
| break; |
| } |
| |
| return aes_set_key(tfm, in_key, key_len); |
| } |
| |
| static int ecb_aes_crypt(struct blkcipher_desc *desc, long func, void *param, |
| struct blkcipher_walk *walk) |
| { |
| int ret = blkcipher_walk_virt(desc, walk); |
| unsigned int nbytes; |
| |
| while ((nbytes = walk->nbytes)) { |
| /* only use complete blocks */ |
| unsigned int n = nbytes & ~(AES_BLOCK_SIZE - 1); |
| u8 *out = walk->dst.virt.addr; |
| u8 *in = walk->src.virt.addr; |
| |
| ret = crypt_s390_km(func, param, out, in, n); |
| BUG_ON((ret < 0) || (ret != n)); |
| |
| nbytes &= AES_BLOCK_SIZE - 1; |
| ret = blkcipher_walk_done(desc, walk, nbytes); |
| } |
| |
| return ret; |
| } |
| |
| static int ecb_aes_encrypt(struct blkcipher_desc *desc, |
| struct scatterlist *dst, struct scatterlist *src, |
| unsigned int nbytes) |
| { |
| struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); |
| struct blkcipher_walk walk; |
| |
| if (unlikely(need_fallback(sctx->key_len))) |
| return fallback_blk_enc(desc, dst, src, nbytes); |
| |
| blkcipher_walk_init(&walk, dst, src, nbytes); |
| return ecb_aes_crypt(desc, sctx->enc, sctx->key, &walk); |
| } |
| |
| static int ecb_aes_decrypt(struct blkcipher_desc *desc, |
| struct scatterlist *dst, struct scatterlist *src, |
| unsigned int nbytes) |
| { |
| struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); |
| struct blkcipher_walk walk; |
| |
| if (unlikely(need_fallback(sctx->key_len))) |
| return fallback_blk_dec(desc, dst, src, nbytes); |
| |
| blkcipher_walk_init(&walk, dst, src, nbytes); |
| return ecb_aes_crypt(desc, sctx->dec, sctx->key, &walk); |
| } |
| |
| static int fallback_init_blk(struct crypto_tfm *tfm) |
| { |
| const char *name = tfm->__crt_alg->cra_name; |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| |
| sctx->fallback.blk = crypto_alloc_blkcipher(name, 0, |
| CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); |
| |
| if (IS_ERR(sctx->fallback.blk)) { |
| printk(KERN_ERR "Error allocating fallback algo %s\n", name); |
| return PTR_ERR(sctx->fallback.blk); |
| } |
| |
| return 0; |
| } |
| |
| static void fallback_exit_blk(struct crypto_tfm *tfm) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| |
| crypto_free_blkcipher(sctx->fallback.blk); |
| sctx->fallback.blk = NULL; |
| } |
| |
| static struct crypto_alg ecb_aes_alg = { |
| .cra_name = "ecb(aes)", |
| .cra_driver_name = "ecb-aes-s390", |
| .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY, |
| .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | |
| CRYPTO_ALG_NEED_FALLBACK, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct s390_aes_ctx), |
| .cra_type = &crypto_blkcipher_type, |
| .cra_module = THIS_MODULE, |
| .cra_list = LIST_HEAD_INIT(ecb_aes_alg.cra_list), |
| .cra_init = fallback_init_blk, |
| .cra_exit = fallback_exit_blk, |
| .cra_u = { |
| .blkcipher = { |
| .min_keysize = AES_MIN_KEY_SIZE, |
| .max_keysize = AES_MAX_KEY_SIZE, |
| .setkey = ecb_aes_set_key, |
| .encrypt = ecb_aes_encrypt, |
| .decrypt = ecb_aes_decrypt, |
| } |
| } |
| }; |
| |
| static int cbc_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, |
| unsigned int key_len) |
| { |
| struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm); |
| int ret; |
| |
| ret = need_fallback(key_len); |
| if (ret > 0) { |
| sctx->key_len = key_len; |
| return setkey_fallback_blk(tfm, in_key, key_len); |
| } |
| |
| switch (key_len) { |
| case 16: |
| sctx->enc = KMC_AES_128_ENCRYPT; |
| sctx->dec = KMC_AES_128_DECRYPT; |
| break; |
| case 24: |
| sctx->enc = KMC_AES_192_ENCRYPT; |
| sctx->dec = KMC_AES_192_DECRYPT; |
| break; |
| case 32: |
| sctx->enc = KMC_AES_256_ENCRYPT; |
| sctx->dec = KMC_AES_256_DECRYPT; |
| break; |
| } |
| |
| return aes_set_key(tfm, in_key, key_len); |
| } |
| |
| static int cbc_aes_crypt(struct blkcipher_desc *desc, long func, void *param, |
| struct blkcipher_walk *walk) |
| { |
| int ret = blkcipher_walk_virt(desc, walk); |
| unsigned int nbytes = walk->nbytes; |
| |
| if (!nbytes) |
| goto out; |
| |
| memcpy(param, walk->iv, AES_BLOCK_SIZE); |
| do { |
| /* only use complete blocks */ |
| unsigned int n = nbytes & ~(AES_BLOCK_SIZE - 1); |
| u8 *out = walk->dst.virt.addr; |
| u8 *in = walk->src.virt.addr; |
| |
| ret = crypt_s390_kmc(func, param, out, in, n); |
| BUG_ON((ret < 0) || (ret != n)); |
| |
| nbytes &= AES_BLOCK_SIZE - 1; |
| ret = blkcipher_walk_done(desc, walk, nbytes); |
| } while ((nbytes = walk->nbytes)); |
| memcpy(walk->iv, param, AES_BLOCK_SIZE); |
| |
| out: |
| return ret; |
| } |
| |
| static int cbc_aes_encrypt(struct blkcipher_desc *desc, |
| struct scatterlist *dst, struct scatterlist *src, |
| unsigned int nbytes) |
| { |
| struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); |
| struct blkcipher_walk walk; |
| |
| if (unlikely(need_fallback(sctx->key_len))) |
| return fallback_blk_enc(desc, dst, src, nbytes); |
| |
| blkcipher_walk_init(&walk, dst, src, nbytes); |
| return cbc_aes_crypt(desc, sctx->enc, sctx->iv, &walk); |
| } |
| |
| static int cbc_aes_decrypt(struct blkcipher_desc *desc, |
| struct scatterlist *dst, struct scatterlist *src, |
| unsigned int nbytes) |
| { |
| struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm); |
| struct blkcipher_walk walk; |
| |
| if (unlikely(need_fallback(sctx->key_len))) |
| return fallback_blk_dec(desc, dst, src, nbytes); |
| |
| blkcipher_walk_init(&walk, dst, src, nbytes); |
| return cbc_aes_crypt(desc, sctx->dec, sctx->iv, &walk); |
| } |
| |
| static struct crypto_alg cbc_aes_alg = { |
| .cra_name = "cbc(aes)", |
| .cra_driver_name = "cbc-aes-s390", |
| .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY, |
| .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER | |
| CRYPTO_ALG_NEED_FALLBACK, |
| .cra_blocksize = AES_BLOCK_SIZE, |
| .cra_ctxsize = sizeof(struct s390_aes_ctx), |
| .cra_type = &crypto_blkcipher_type, |
| .cra_module = THIS_MODULE, |
| .cra_list = LIST_HEAD_INIT(cbc_aes_alg.cra_list), |
| .cra_init = fallback_init_blk, |
| .cra_exit = fallback_exit_blk, |
| .cra_u = { |
| .blkcipher = { |
| .min_keysize = AES_MIN_KEY_SIZE, |
| .max_keysize = AES_MAX_KEY_SIZE, |
| .ivsize = AES_BLOCK_SIZE, |
| .setkey = cbc_aes_set_key, |
| .encrypt = cbc_aes_encrypt, |
| .decrypt = cbc_aes_decrypt, |
| } |
| } |
| }; |
| |
| static int __init aes_init(void) |
| { |
| int ret; |
| |
| if (crypt_s390_func_available(KM_AES_128_ENCRYPT)) |
| keylen_flag |= AES_KEYLEN_128; |
| if (crypt_s390_func_available(KM_AES_192_ENCRYPT)) |
| keylen_flag |= AES_KEYLEN_192; |
| if (crypt_s390_func_available(KM_AES_256_ENCRYPT)) |
| keylen_flag |= AES_KEYLEN_256; |
| |
| if (!keylen_flag) |
| return -EOPNOTSUPP; |
| |
| /* z9 109 and z9 BC/EC only support 128 bit key length */ |
| if (keylen_flag == AES_KEYLEN_128) |
| printk(KERN_INFO |
| "aes_s390: hardware acceleration only available for" |
| "128 bit keys\n"); |
| |
| ret = crypto_register_alg(&aes_alg); |
| if (ret) |
| goto aes_err; |
| |
| ret = crypto_register_alg(&ecb_aes_alg); |
| if (ret) |
| goto ecb_aes_err; |
| |
| ret = crypto_register_alg(&cbc_aes_alg); |
| if (ret) |
| goto cbc_aes_err; |
| |
| out: |
| return ret; |
| |
| cbc_aes_err: |
| crypto_unregister_alg(&ecb_aes_alg); |
| ecb_aes_err: |
| crypto_unregister_alg(&aes_alg); |
| aes_err: |
| goto out; |
| } |
| |
| static void __exit aes_fini(void) |
| { |
| crypto_unregister_alg(&cbc_aes_alg); |
| crypto_unregister_alg(&ecb_aes_alg); |
| crypto_unregister_alg(&aes_alg); |
| } |
| |
| module_init(aes_init); |
| module_exit(aes_fini); |
| |
| MODULE_ALIAS("aes"); |
| |
| MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm"); |
| MODULE_LICENSE("GPL"); |