diff options
| -rw-r--r-- | arch/s390/crypto/aes_s390.c | 233 | ||||
| -rw-r--r-- | arch/s390/crypto/crypt_s390.h | 31 | ||||
| -rw-r--r-- | drivers/crypto/Kconfig | 22 |
3 files changed, 272 insertions, 14 deletions
diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c index fc97b94..8230e86 100644 --- a/arch/s390/crypto/aes_s390.c +++ b/arch/s390/crypto/aes_s390.c @@ -45,6 +45,24 @@ struct s390_aes_ctx { } fallback; }; +struct pcc_param { + u8 key[32]; + u8 tweak[16]; + u8 block[16]; + u8 bit[16]; + u8 xts[16]; +}; + +struct s390_xts_ctx { + u8 key[32]; + u8 xts_param[16]; + struct pcc_param pcc; + long enc; + long dec; + int key_len; + struct crypto_blkcipher *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 @@ -504,8 +522,211 @@ static struct crypto_alg cbc_aes_alg = { } }; +static int xts_fallback_setkey(struct crypto_tfm *tfm, const u8 *key, + unsigned int len) +{ + struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); + unsigned int ret; + + xts_ctx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK; + xts_ctx->fallback->base.crt_flags |= (tfm->crt_flags & + CRYPTO_TFM_REQ_MASK); + + ret = crypto_blkcipher_setkey(xts_ctx->fallback, key, len); + if (ret) { + tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK; + tfm->crt_flags |= (xts_ctx->fallback->base.crt_flags & + CRYPTO_TFM_RES_MASK); + } + return ret; +} + +static int xts_fallback_decrypt(struct blkcipher_desc *desc, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); + struct crypto_blkcipher *tfm; + unsigned int ret; + + tfm = desc->tfm; + desc->tfm = xts_ctx->fallback; + + ret = crypto_blkcipher_decrypt_iv(desc, dst, src, nbytes); + + desc->tfm = tfm; + return ret; +} + +static int xts_fallback_encrypt(struct blkcipher_desc *desc, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); + struct crypto_blkcipher *tfm; + unsigned int ret; + + tfm = desc->tfm; + desc->tfm = xts_ctx->fallback; + + ret = crypto_blkcipher_encrypt_iv(desc, dst, src, nbytes); + + desc->tfm = tfm; + return ret; +} + +static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key, + unsigned int key_len) +{ + struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); + u32 *flags = &tfm->crt_flags; + + switch (key_len) { + case 32: + xts_ctx->enc = KM_XTS_128_ENCRYPT; + xts_ctx->dec = KM_XTS_128_DECRYPT; + memcpy(xts_ctx->key + 16, in_key, 16); + memcpy(xts_ctx->pcc.key + 16, in_key + 16, 16); + break; + case 48: + xts_ctx->enc = 0; + xts_ctx->dec = 0; + xts_fallback_setkey(tfm, in_key, key_len); + break; + case 64: + xts_ctx->enc = KM_XTS_256_ENCRYPT; + xts_ctx->dec = KM_XTS_256_DECRYPT; + memcpy(xts_ctx->key, in_key, 32); + memcpy(xts_ctx->pcc.key, in_key + 32, 32); + break; + default: + *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; + return -EINVAL; + } + xts_ctx->key_len = key_len; + return 0; +} + +static int xts_aes_crypt(struct blkcipher_desc *desc, long func, + struct s390_xts_ctx *xts_ctx, + struct blkcipher_walk *walk) +{ + unsigned int offset = (xts_ctx->key_len >> 1) & 0x10; + int ret = blkcipher_walk_virt(desc, walk); + unsigned int nbytes = walk->nbytes; + unsigned int n; + u8 *in, *out; + void *param; + + if (!nbytes) + goto out; + + memset(xts_ctx->pcc.block, 0, sizeof(xts_ctx->pcc.block)); + memset(xts_ctx->pcc.bit, 0, sizeof(xts_ctx->pcc.bit)); + memset(xts_ctx->pcc.xts, 0, sizeof(xts_ctx->pcc.xts)); + memcpy(xts_ctx->pcc.tweak, walk->iv, sizeof(xts_ctx->pcc.tweak)); + param = xts_ctx->pcc.key + offset; + ret = crypt_s390_pcc(func, param); + BUG_ON(ret < 0); + + memcpy(xts_ctx->xts_param, xts_ctx->pcc.xts, 16); + param = xts_ctx->key + offset; + do { + /* only use complete blocks */ + n = nbytes & ~(AES_BLOCK_SIZE - 1); + out = walk->dst.virt.addr; + 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); + } while ((nbytes = walk->nbytes)); +out: + return ret; +} + +static int xts_aes_encrypt(struct blkcipher_desc *desc, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); + struct blkcipher_walk walk; + + if (unlikely(xts_ctx->key_len == 48)) + return xts_fallback_encrypt(desc, dst, src, nbytes); + + blkcipher_walk_init(&walk, dst, src, nbytes); + return xts_aes_crypt(desc, xts_ctx->enc, xts_ctx, &walk); +} + +static int xts_aes_decrypt(struct blkcipher_desc *desc, + struct scatterlist *dst, struct scatterlist *src, + unsigned int nbytes) +{ + struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm); + struct blkcipher_walk walk; + + if (unlikely(xts_ctx->key_len == 48)) + return xts_fallback_decrypt(desc, dst, src, nbytes); + + blkcipher_walk_init(&walk, dst, src, nbytes); + return xts_aes_crypt(desc, xts_ctx->dec, xts_ctx, &walk); +} + +static int xts_fallback_init(struct crypto_tfm *tfm) +{ + const char *name = tfm->__crt_alg->cra_name; + struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); + + xts_ctx->fallback = crypto_alloc_blkcipher(name, 0, + CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK); + + if (IS_ERR(xts_ctx->fallback)) { + pr_err("Allocating XTS fallback algorithm %s failed\n", + name); + return PTR_ERR(xts_ctx->fallback); + } + return 0; +} + +static void xts_fallback_exit(struct crypto_tfm *tfm) +{ + struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm); + + crypto_free_blkcipher(xts_ctx->fallback); + xts_ctx->fallback = NULL; +} + +static struct crypto_alg xts_aes_alg = { + .cra_name = "xts(aes)", + .cra_driver_name = "xts-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_xts_ctx), + .cra_type = &crypto_blkcipher_type, + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(xts_aes_alg.cra_list), + .cra_init = xts_fallback_init, + .cra_exit = xts_fallback_exit, + .cra_u = { + .blkcipher = { + .min_keysize = 2 * AES_MIN_KEY_SIZE, + .max_keysize = 2 * AES_MAX_KEY_SIZE, + .ivsize = AES_BLOCK_SIZE, + .setkey = xts_aes_set_key, + .encrypt = xts_aes_encrypt, + .decrypt = xts_aes_decrypt, + } + } +}; + static int __init aes_s390_init(void) { + unsigned long long facility_bits[2]; int ret; if (crypt_s390_func_available(KM_AES_128_ENCRYPT, CRYPT_S390_MSA)) @@ -535,9 +756,20 @@ static int __init aes_s390_init(void) if (ret) goto cbc_aes_err; + if (crypt_s390_func_available(KM_XTS_128_ENCRYPT, + CRYPT_S390_MSA | CRYPT_S390_MSA4) && + crypt_s390_func_available(KM_XTS_256_ENCRYPT, + CRYPT_S390_MSA | CRYPT_S390_MSA4)) { + ret = crypto_register_alg(&xts_aes_alg); + if (ret) + goto xts_aes_err; + } + out: return ret; +xts_aes_err: + crypto_unregister_alg(&cbc_aes_alg); cbc_aes_err: crypto_unregister_alg(&ecb_aes_alg); ecb_aes_err: @@ -548,6 +780,7 @@ aes_err: static void __exit aes_s390_fini(void) { + crypto_unregister_alg(&xts_aes_alg); crypto_unregister_alg(&cbc_aes_alg); crypto_unregister_alg(&ecb_aes_alg); crypto_unregister_alg(&aes_alg); diff --git a/arch/s390/crypto/crypt_s390.h b/arch/s390/crypto/crypt_s390.h index 4b8c96c..7cbfaf0 100644 --- a/arch/s390/crypto/crypt_s390.h +++ b/arch/s390/crypto/crypt_s390.h @@ -55,6 +55,10 @@ enum crypt_s390_km_func { KM_AES_192_DECRYPT = CRYPT_S390_KM | 0x13 | 0x80, KM_AES_256_ENCRYPT = CRYPT_S390_KM | 0x14, KM_AES_256_DECRYPT = CRYPT_S390_KM | 0x14 | 0x80, + KM_XTS_128_ENCRYPT = CRYPT_S390_KM | 0x32, + KM_XTS_128_DECRYPT = CRYPT_S390_KM | 0x32 | 0x80, + KM_XTS_256_ENCRYPT = CRYPT_S390_KM | 0x34, + KM_XTS_256_DECRYPT = CRYPT_S390_KM | 0x34 | 0x80, }; /* @@ -334,4 +338,31 @@ static inline int crypt_s390_func_available(int func, return (status[func >> 3] & (0x80 >> (func & 7))) != 0; } +/** + * crypt_s390_pcc: + * @func: the function code passed to KM; see crypt_s390_km_func + * @param: address of parameter block; see POP for details on each func + * + * Executes the PCC (PERFORM CRYPTOGRAPHIC COMPUTATION) operation of the CPU. + * + * Returns -1 for failure, 0 for success. + */ +static inline int crypt_s390_pcc(long func, void *param) +{ + register long __func asm("0") = func & 0x7f; /* encrypt or decrypt */ + register void *__param asm("1") = param; + int ret = -1; + + asm volatile( + "0: .insn rre,0xb92c0000,0,0 \n" /* PCC opcode */ + "1: brc 1,0b \n" /* handle partial completion */ + " la %0,0\n" + "2:\n" + EX_TABLE(0b,2b) EX_TABLE(1b,2b) + : "+d" (ret) + : "d" (__func), "a" (__param) : "cc", "memory"); + return ret; +} + + #endif /* _CRYPTO_ARCH_S390_CRYPT_S390_H */ diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig index 7957acb..78df36a 100644 --- a/drivers/crypto/Kconfig +++ b/drivers/crypto/Kconfig @@ -131,20 +131,14 @@ config CRYPTO_AES_S390 select CRYPTO_BLKCIPHER help This is the s390 hardware accelerated implementation of the - AES cipher algorithms (FIPS-197). AES uses the Rijndael - algorithm. - - Rijndael appears to be consistently a very good performer in - both hardware and software across a wide range of computing - environments regardless of its use in feedback or non-feedback - modes. Its key setup time is excellent, and its key agility is - good. Rijndael's very low memory requirements make it very well - suited for restricted-space environments, in which it also - demonstrates excellent performance. Rijndael's operations are - among the easiest to defend against power and timing attacks. - - On s390 the System z9-109 currently only supports the key size - of 128 bit. + AES cipher algorithms (FIPS-197). + + As of z9 the ECB and CBC modes are hardware accelerated + for 128 bit keys. + As of z10 the ECB and CBC modes are hardware accelerated + for all AES key sizes. + As of z196 the XTS mode is hardware accelerated for 256 and + 512 bit keys. config S390_PRNG tristate "Pseudo random number generator device driver" |