This patch adds support for the aes-ctr skcipher.
name : ctr(aes)
driver : ctr-aes-ppc4xx
module : crypto4xx
priority : 300
refcnt : 1
selftest : passed
internal : no
type : skcipher
async : yes
blocksize : 16
min keysize : 16
max keysize : 32
ivsize : 16
chunksize : 16
walksize : 16
The hardware uses only the last 32-bits as the counter while the
kernel tests (aes_ctr_enc_tv_template[4] for example) expect that
the whole IV is a counter. To make this work, the driver will
fallback if the counter is going to overlow.
The aead's crypto4xx_setup_fallback() function is renamed to
crypto4xx_aead_setup_fallback.
Signed-off-by: Christian Lamparter <chunkeey@xxxxxxxxx>
---
drivers/crypto/Kconfig | 1 +
drivers/crypto/amcc/crypto4xx_alg.c | 91 ++++++++++++++++++++++++++--
drivers/crypto/amcc/crypto4xx_core.c | 37 +++++++++++
drivers/crypto/amcc/crypto4xx_core.h | 5 ++
4 files changed, 128 insertions(+), 6 deletions(-)
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index d1ea1a07cecb..da7fc7753003 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -302,6 +302,7 @@ config CRYPTO_DEV_PPC4XX
select CRYPTO_AEAD
select CRYPTO_AES
select CRYPTO_CCM
+ select CRYPTO_CTR
select CRYPTO_GCM
select CRYPTO_BLKCIPHER
help
diff --git a/drivers/crypto/amcc/crypto4xx_alg.c b/drivers/crypto/amcc/crypto4xx_alg.c
index 2dfeb71deca9..8a352ddefd52 100644
--- a/drivers/crypto/amcc/crypto4xx_alg.c
+++ b/drivers/crypto/amcc/crypto4xx_alg.c
@@ -240,6 +240,85 @@ int crypto4xx_rfc3686_decrypt(struct skcipher_request *req)
ctx->sa_out, ctx->sa_len, 0);
}
+static int
+crypto4xx_ctr_crypt(struct skcipher_request *req, bool encrypt)
+{
+ struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(req);
+ struct crypto4xx_ctx *ctx = crypto_skcipher_ctx(cipher);
+ size_t iv_len = crypto_skcipher_ivsize(cipher);
+ unsigned int counter = be32_to_cpup((__be32 *)(req->iv + iv_len - 4));
+ unsigned int nblks = ALIGN(req->cryptlen, AES_BLOCK_SIZE) /
+ AES_BLOCK_SIZE;
+
+ /*
+ * The hardware uses only the last 32-bits as the counter while the
+ * kernel tests (aes_ctr_enc_tv_template[4] for example) expect that
+ * the whole IV is a counter. So fallback if the counter is going to
+ * overlow.
+ */
+ if (counter + nblks < counter) {
+ struct skcipher_request *subreq = skcipher_request_ctx(req);
+ int ret;
+
+ skcipher_request_set_tfm(subreq, ctx->sw_cipher.cipher);
+ skcipher_request_set_callback(subreq, req->base.flags,
+ NULL, NULL);
+ skcipher_request_set_crypt(subreq, req->src, req->dst,
+ req->cryptlen, req->iv);
+ ret = encrypt ? crypto_skcipher_encrypt(subreq)
+ : crypto_skcipher_decrypt(subreq);
+ skcipher_request_zero(subreq);
+ return ret;
+ }
+
+ return encrypt ? crypto4xx_encrypt_iv(req)
+ : crypto4xx_decrypt_iv(req);
+}
+
+static int crypto4xx_sk_setup_fallback(struct crypto4xx_ctx *ctx,
+ struct crypto_skcipher *cipher,
+ const u8 *key,
+ unsigned int keylen)
+{
+ int rc;
+
+ crypto_skcipher_clear_flags(ctx->sw_cipher.cipher,
+ CRYPTO_TFM_REQ_MASK);
+ crypto_skcipher_set_flags(ctx->sw_cipher.cipher,
+ crypto_skcipher_get_flags(cipher) & CRYPTO_TFM_REQ_MASK);
+ rc = crypto_skcipher_setkey(ctx->sw_cipher.cipher, key, keylen);
+ crypto_skcipher_clear_flags(cipher, CRYPTO_TFM_RES_MASK);
+ crypto_skcipher_set_flags(cipher,
+ crypto_skcipher_get_flags(ctx->sw_cipher.cipher) &
+ CRYPTO_TFM_RES_MASK);
+
+ return rc;
+}
+
+int crypto4xx_setkey_aes_ctr(struct crypto_skcipher *cipher,
+ const u8 *key, unsigned int keylen)
+{
+ struct crypto4xx_ctx *ctx = crypto_skcipher_ctx(cipher);
+ int rc;
+
+ rc = crypto4xx_sk_setup_fallback(ctx, cipher, key, keylen);
+ if (rc)
+ return rc;
+
+ return crypto4xx_setkey_aes(cipher, key, keylen,
+ CRYPTO_MODE_CTR, CRYPTO_FEEDBACK_MODE_NO_FB);
+}
+
+int crypto4xx_encrypt_ctr(struct skcipher_request *req)
+{
+ return crypto4xx_ctr_crypt(req, true);
+}
+
+int crypto4xx_decrypt_ctr(struct skcipher_request *req)
+{
+ return crypto4xx_ctr_crypt(req, false);
+}
+
static inline bool crypto4xx_aead_need_fallback(struct aead_request *req,
bool is_ccm, bool decrypt)
{
@@ -282,10 +361,10 @@ static int crypto4xx_aead_fallback(struct aead_request *req,
crypto_aead_encrypt(subreq);
}
-static int crypto4xx_setup_fallback(struct crypto4xx_ctx *ctx,
- struct crypto_aead *cipher,
- const u8 *key,
- unsigned int keylen)
+static int crypto4xx_aead_setup_fallback(struct crypto4xx_ctx *ctx,
+ struct crypto_aead *cipher,
+ const u8 *key,
+ unsigned int keylen)
{
int rc;
@@ -313,7 +392,7 @@ int crypto4xx_setkey_aes_ccm(struct crypto_aead *cipher, const u8 *key,
struct dynamic_sa_ctl *sa;
int rc = 0;
- rc = crypto4xx_setup_fallback(ctx, cipher, key, keylen);
+ rc = crypto4xx_aead_setup_fallback(ctx, cipher, key, keylen);
if (rc)
return rc;
@@ -472,7 +551,7 @@ int crypto4xx_setkey_aes_gcm(struct crypto_aead *cipher,
return -EINVAL;
}
- rc = crypto4xx_setup_fallback(ctx, cipher, key, keylen);
+ rc = crypto4xx_aead_setup_fallback(ctx, cipher, key, keylen);
if (rc)
return rc;
diff --git a/drivers/crypto/amcc/crypto4xx_core.c b/drivers/crypto/amcc/crypto4xx_core.c
index 7d0629626d15..73963928d91b 100644
--- a/drivers/crypto/amcc/crypto4xx_core.c
+++ b/drivers/crypto/amcc/crypto4xx_core.c
@@ -941,6 +941,19 @@ static int crypto4xx_sk_init(struct crypto_skcipher *sk)
struct crypto4xx_alg *amcc_alg;
struct crypto4xx_ctx *ctx = crypto_skcipher_ctx(sk);
+ if (alg->base.cra_flags & CRYPTO_ALG_NEED_FALLBACK) {
+ ctx->sw_cipher.cipher =
+ crypto_alloc_skcipher(alg->base.cra_name, 0,
+ CRYPTO_ALG_NEED_FALLBACK |
+ CRYPTO_ALG_ASYNC);
+ if (IS_ERR(ctx->sw_cipher.cipher))
+ return PTR_ERR(ctx->sw_cipher.cipher);
+
+ crypto_skcipher_set_reqsize(sk,
+ sizeof(struct skcipher_request) + 32 +
+ crypto_skcipher_reqsize(ctx->sw_cipher.cipher));
+ }
+
amcc_alg = container_of(alg, struct crypto4xx_alg, alg.u.cipher);
crypto4xx_ctx_init(amcc_alg, ctx);
return 0;
@@ -956,6 +969,8 @@ static void crypto4xx_sk_exit(struct crypto_skcipher *sk)
struct crypto4xx_ctx *ctx = crypto_skcipher_ctx(sk);
crypto4xx_common_exit(ctx);
+ if (ctx->sw_cipher.cipher)
+ crypto_free_skcipher(ctx->sw_cipher.cipher);
}
static int crypto4xx_aead_init(struct crypto_aead *tfm)
@@ -1145,6 +1160,28 @@ static struct crypto4xx_alg_common crypto4xx_alg[] = {
.init = crypto4xx_sk_init,
.exit = crypto4xx_sk_exit,
} },
+ { .type = CRYPTO_ALG_TYPE_SKCIPHER, .u.cipher = {
+ .base = {
+ .cra_name = "ctr(aes)",
+ .cra_driver_name = "ctr-aes-ppc4xx",
+ .cra_priority = CRYPTO4XX_CRYPTO_PRIORITY,
+ .cra_flags = CRYPTO_ALG_TYPE_SKCIPHER |
+ CRYPTO_ALG_NEED_FALLBACK |
+ CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_KERN_DRIVER_ONLY,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct crypto4xx_ctx),
+ .cra_module = THIS_MODULE,
+ },
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_IV_SIZE,
+ .setkey = crypto4xx_setkey_aes_ctr,
+ .encrypt = crypto4xx_encrypt_ctr,
+ .decrypt = crypto4xx_decrypt_ctr,
+ .init = crypto4xx_sk_init,
+ .exit = crypto4xx_sk_exit,
+ } },
{ .type = CRYPTO_ALG_TYPE_SKCIPHER, .u.cipher = {
.base = {
.cra_name = "rfc3686(ctr(aes))",
diff --git a/drivers/crypto/amcc/crypto4xx_core.h b/drivers/crypto/amcc/crypto4xx_core.h
index 863cc558bc29..279f650c4f1c 100644
--- a/drivers/crypto/amcc/crypto4xx_core.h
+++ b/drivers/crypto/amcc/crypto4xx_core.h
@@ -128,6 +128,7 @@ struct crypto4xx_ctx {
__le32 iv_nonce;
u32 sa_len;
union {
+ struct crypto_skcipher *cipher;
struct crypto_aead *aead;
} sw_cipher;
};
@@ -163,12 +164,16 @@ int crypto4xx_setkey_aes_cbc(struct crypto_skcipher *cipher,
const u8 *key, unsigned int keylen);
int crypto4xx_setkey_aes_cfb(struct crypto_skcipher *cipher,
const u8 *key, unsigned int keylen);
+int crypto4xx_setkey_aes_ctr(struct crypto_skcipher *cipher,
+ const u8 *key, unsigned int keylen);
int crypto4xx_setkey_aes_ecb(struct crypto_skcipher *cipher,
const u8 *key, unsigned int keylen);
int crypto4xx_setkey_aes_ofb(struct crypto_skcipher *cipher,
const u8 *key, unsigned int keylen);
int crypto4xx_setkey_rfc3686(struct crypto_skcipher *cipher,
const u8 *key, unsigned int keylen);
+int crypto4xx_encrypt_ctr(struct skcipher_request *req);
+int crypto4xx_decrypt_ctr(struct skcipher_request *req);
int crypto4xx_encrypt_iv(struct skcipher_request *req);
int crypto4xx_decrypt_iv(struct skcipher_request *req);
int crypto4xx_encrypt_noiv(struct skcipher_request *req);
--
2.17.0
