crypto: s390 - add System z hardware support for CTR mode
This patch adds System z hardware acceleration support for AES, DES
and 3DES in CTR mode. The hardware support is available starting with
System z196.
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
index 8230e86..a9ce135 100644
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -31,7 +31,8 @@
#define AES_KEYLEN_192 2
#define AES_KEYLEN_256 4
-static char keylen_flag = 0;
+static u8 *ctrblk;
+static char keylen_flag;
struct s390_aes_ctx {
u8 iv[AES_BLOCK_SIZE];
@@ -724,9 +725,128 @@
}
};
+static int ctr_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
+ unsigned int key_len)
+{
+ struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
+
+ switch (key_len) {
+ case 16:
+ sctx->enc = KMCTR_AES_128_ENCRYPT;
+ sctx->dec = KMCTR_AES_128_DECRYPT;
+ break;
+ case 24:
+ sctx->enc = KMCTR_AES_192_ENCRYPT;
+ sctx->dec = KMCTR_AES_192_DECRYPT;
+ break;
+ case 32:
+ sctx->enc = KMCTR_AES_256_ENCRYPT;
+ sctx->dec = KMCTR_AES_256_DECRYPT;
+ break;
+ }
+
+ return aes_set_key(tfm, in_key, key_len);
+}
+
+static int ctr_aes_crypt(struct blkcipher_desc *desc, long func,
+ struct s390_aes_ctx *sctx, struct blkcipher_walk *walk)
+{
+ int ret = blkcipher_walk_virt_block(desc, walk, AES_BLOCK_SIZE);
+ unsigned int i, n, nbytes;
+ u8 buf[AES_BLOCK_SIZE];
+ u8 *out, *in;
+
+ if (!walk->nbytes)
+ return ret;
+
+ memcpy(ctrblk, walk->iv, AES_BLOCK_SIZE);
+ while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
+ out = walk->dst.virt.addr;
+ in = walk->src.virt.addr;
+ while (nbytes >= AES_BLOCK_SIZE) {
+ /* only use complete blocks, max. PAGE_SIZE */
+ n = (nbytes > PAGE_SIZE) ? PAGE_SIZE :
+ nbytes & ~(AES_BLOCK_SIZE - 1);
+ for (i = AES_BLOCK_SIZE; i < n; i += AES_BLOCK_SIZE) {
+ memcpy(ctrblk + i, ctrblk + i - AES_BLOCK_SIZE,
+ AES_BLOCK_SIZE);
+ crypto_inc(ctrblk + i, AES_BLOCK_SIZE);
+ }
+ ret = crypt_s390_kmctr(func, sctx->key, out, in, n, ctrblk);
+ BUG_ON(ret < 0 || ret != n);
+ if (n > AES_BLOCK_SIZE)
+ memcpy(ctrblk, ctrblk + n - AES_BLOCK_SIZE,
+ AES_BLOCK_SIZE);
+ crypto_inc(ctrblk, AES_BLOCK_SIZE);
+ out += n;
+ in += n;
+ nbytes -= n;
+ }
+ ret = blkcipher_walk_done(desc, walk, nbytes);
+ }
+ /*
+ * final block may be < AES_BLOCK_SIZE, copy only nbytes
+ */
+ if (nbytes) {
+ out = walk->dst.virt.addr;
+ in = walk->src.virt.addr;
+ ret = crypt_s390_kmctr(func, sctx->key, buf, in,
+ AES_BLOCK_SIZE, ctrblk);
+ BUG_ON(ret < 0 || ret != AES_BLOCK_SIZE);
+ memcpy(out, buf, nbytes);
+ crypto_inc(ctrblk, AES_BLOCK_SIZE);
+ ret = blkcipher_walk_done(desc, walk, 0);
+ }
+ memcpy(walk->iv, ctrblk, AES_BLOCK_SIZE);
+ return ret;
+}
+
+static int ctr_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;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ return ctr_aes_crypt(desc, sctx->enc, sctx, &walk);
+}
+
+static int ctr_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;
+
+ blkcipher_walk_init(&walk, dst, src, nbytes);
+ return ctr_aes_crypt(desc, sctx->dec, sctx, &walk);
+}
+
+static struct crypto_alg ctr_aes_alg = {
+ .cra_name = "ctr(aes)",
+ .cra_driver_name = "ctr-aes-s390",
+ .cra_priority = CRYPT_S390_COMPOSITE_PRIORITY,
+ .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
+ .cra_blocksize = 1,
+ .cra_ctxsize = sizeof(struct s390_aes_ctx),
+ .cra_type = &crypto_blkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_list = LIST_HEAD_INIT(ctr_aes_alg.cra_list),
+ .cra_u = {
+ .blkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = ctr_aes_set_key,
+ .encrypt = ctr_aes_encrypt,
+ .decrypt = ctr_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))
@@ -765,9 +885,29 @@
goto xts_aes_err;
}
+ if (crypt_s390_func_available(KMCTR_AES_128_ENCRYPT,
+ CRYPT_S390_MSA | CRYPT_S390_MSA4) &&
+ crypt_s390_func_available(KMCTR_AES_192_ENCRYPT,
+ CRYPT_S390_MSA | CRYPT_S390_MSA4) &&
+ crypt_s390_func_available(KMCTR_AES_256_ENCRYPT,
+ CRYPT_S390_MSA | CRYPT_S390_MSA4)) {
+ ctrblk = (u8 *) __get_free_page(GFP_KERNEL);
+ if (!ctrblk) {
+ ret = -ENOMEM;
+ goto ctr_aes_err;
+ }
+ ret = crypto_register_alg(&ctr_aes_alg);
+ if (ret) {
+ free_page((unsigned long) ctrblk);
+ goto ctr_aes_err;
+ }
+ }
+
out:
return ret;
+ctr_aes_err:
+ crypto_unregister_alg(&xts_aes_alg);
xts_aes_err:
crypto_unregister_alg(&cbc_aes_alg);
cbc_aes_err:
@@ -780,6 +920,8 @@
static void __exit aes_s390_fini(void)
{
+ crypto_unregister_alg(&ctr_aes_alg);
+ free_page((unsigned long) ctrblk);
crypto_unregister_alg(&xts_aes_alg);
crypto_unregister_alg(&cbc_aes_alg);
crypto_unregister_alg(&ecb_aes_alg);