summaryrefslogtreecommitdiff
path: root/drivers/crypto/amcc/crypto4xx_alg.c
diff options
context:
space:
mode:
authorChristian Lamparter <chunkeey@gmail.com>2018-04-19 19:41:54 +0300
committerHerbert Xu <herbert@gondor.apana.org.au>2018-04-28 11:09:43 +0300
commit98e87e3d933b8e504ea41b8857c038d2cd06cddc (patch)
tree49f9dea288fa426f43118b11da4b1beee71bdcca /drivers/crypto/amcc/crypto4xx_alg.c
parentc4e90650ff0cbf123ec9cfc32026fa0fb2931658 (diff)
downloadlinux-98e87e3d933b8e504ea41b8857c038d2cd06cddc.tar.xz
crypto: crypto4xx - add aes-ctr support
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@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto/amcc/crypto4xx_alg.c')
-rw-r--r--drivers/crypto/amcc/crypto4xx_alg.c91
1 files changed, 85 insertions, 6 deletions
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;