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path: root/drivers/crypto/atmel-aes.c
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Diffstat (limited to 'drivers/crypto/atmel-aes.c')
-rw-r--r--drivers/crypto/atmel-aes.c117
1 files changed, 115 insertions, 2 deletions
diff --git a/drivers/crypto/atmel-aes.c b/drivers/crypto/atmel-aes.c
index 5f6dc48616c0..a34919f6b7d7 100644
--- a/drivers/crypto/atmel-aes.c
+++ b/drivers/crypto/atmel-aes.c
@@ -82,6 +82,7 @@
struct atmel_aes_caps {
bool has_dualbuff;
bool has_cfb64;
+ bool has_ctr32;
u32 max_burst_size;
};
@@ -103,6 +104,15 @@ struct atmel_aes_ctx {
struct atmel_aes_base_ctx base;
};
+struct atmel_aes_ctr_ctx {
+ struct atmel_aes_base_ctx base;
+
+ u32 iv[AES_BLOCK_SIZE / sizeof(u32)];
+ size_t offset;
+ struct scatterlist src[2];
+ struct scatterlist dst[2];
+};
+
struct atmel_aes_reqctx {
unsigned long mode;
};
@@ -762,6 +772,96 @@ static int atmel_aes_start(struct atmel_aes_dev *dd)
atmel_aes_transfer_complete);
}
+static inline struct atmel_aes_ctr_ctx *
+atmel_aes_ctr_ctx_cast(struct atmel_aes_base_ctx *ctx)
+{
+ return container_of(ctx, struct atmel_aes_ctr_ctx, base);
+}
+
+static int atmel_aes_ctr_transfer(struct atmel_aes_dev *dd)
+{
+ struct atmel_aes_ctr_ctx *ctx = atmel_aes_ctr_ctx_cast(dd->ctx);
+ struct ablkcipher_request *req = ablkcipher_request_cast(dd->areq);
+ struct scatterlist *src, *dst;
+ u32 ctr, blocks;
+ size_t datalen;
+ bool use_dma, fragmented = false;
+
+ /* Check for transfer completion. */
+ ctx->offset += dd->total;
+ if (ctx->offset >= req->nbytes)
+ return atmel_aes_transfer_complete(dd);
+
+ /* Compute data length. */
+ datalen = req->nbytes - ctx->offset;
+ blocks = DIV_ROUND_UP(datalen, AES_BLOCK_SIZE);
+ ctr = be32_to_cpu(ctx->iv[3]);
+ if (dd->caps.has_ctr32) {
+ /* Check 32bit counter overflow. */
+ u32 start = ctr;
+ u32 end = start + blocks - 1;
+
+ if (end < start) {
+ ctr |= 0xffffffff;
+ datalen = AES_BLOCK_SIZE * -start;
+ fragmented = true;
+ }
+ } else {
+ /* Check 16bit counter overflow. */
+ u16 start = ctr & 0xffff;
+ u16 end = start + (u16)blocks - 1;
+
+ if (blocks >> 16 || end < start) {
+ ctr |= 0xffff;
+ datalen = AES_BLOCK_SIZE * (0x10000-start);
+ fragmented = true;
+ }
+ }
+ use_dma = (datalen >= ATMEL_AES_DMA_THRESHOLD);
+
+ /* Jump to offset. */
+ src = scatterwalk_ffwd(ctx->src, req->src, ctx->offset);
+ dst = ((req->src == req->dst) ? src :
+ scatterwalk_ffwd(ctx->dst, req->dst, ctx->offset));
+
+ /* Configure hardware. */
+ atmel_aes_write_ctrl(dd, use_dma, ctx->iv);
+ if (unlikely(fragmented)) {
+ /*
+ * Increment the counter manually to cope with the hardware
+ * counter overflow.
+ */
+ ctx->iv[3] = cpu_to_be32(ctr);
+ crypto_inc((u8 *)ctx->iv, AES_BLOCK_SIZE);
+ }
+
+ if (use_dma)
+ return atmel_aes_dma_start(dd, src, dst, datalen,
+ atmel_aes_ctr_transfer);
+
+ return atmel_aes_cpu_start(dd, src, dst, datalen,
+ atmel_aes_ctr_transfer);
+}
+
+static int atmel_aes_ctr_start(struct atmel_aes_dev *dd)
+{
+ struct atmel_aes_ctr_ctx *ctx = atmel_aes_ctr_ctx_cast(dd->ctx);
+ struct ablkcipher_request *req = ablkcipher_request_cast(dd->areq);
+ struct atmel_aes_reqctx *rctx = ablkcipher_request_ctx(req);
+ int err;
+
+ atmel_aes_set_mode(dd, rctx);
+
+ err = atmel_aes_hw_init(dd);
+ if (err)
+ return atmel_aes_complete(dd, err);
+
+ memcpy(ctx->iv, req->info, AES_BLOCK_SIZE);
+ ctx->offset = 0;
+ dd->total = 0;
+ return atmel_aes_ctr_transfer(dd);
+}
+
static int atmel_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
{
struct atmel_aes_base_ctx *ctx;
@@ -919,6 +1019,16 @@ static int atmel_aes_cra_init(struct crypto_tfm *tfm)
return 0;
}
+static int atmel_aes_ctr_cra_init(struct crypto_tfm *tfm)
+{
+ struct atmel_aes_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ tfm->crt_ablkcipher.reqsize = sizeof(struct atmel_aes_reqctx);
+ ctx->base.start = atmel_aes_ctr_start;
+
+ return 0;
+}
+
static void atmel_aes_cra_exit(struct crypto_tfm *tfm)
{
}
@@ -1076,11 +1186,11 @@ static struct crypto_alg aes_algs[] = {
.cra_priority = ATMEL_AES_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
.cra_blocksize = 1,
- .cra_ctxsize = sizeof(struct atmel_aes_ctx),
+ .cra_ctxsize = sizeof(struct atmel_aes_ctr_ctx),
.cra_alignmask = 0xf,
.cra_type = &crypto_ablkcipher_type,
.cra_module = THIS_MODULE,
- .cra_init = atmel_aes_cra_init,
+ .cra_init = atmel_aes_ctr_cra_init,
.cra_exit = atmel_aes_cra_exit,
.cra_u.ablkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
@@ -1262,6 +1372,7 @@ static void atmel_aes_get_cap(struct atmel_aes_dev *dd)
{
dd->caps.has_dualbuff = 0;
dd->caps.has_cfb64 = 0;
+ dd->caps.has_ctr32 = 0;
dd->caps.max_burst_size = 1;
/* keep only major version number */
@@ -1269,11 +1380,13 @@ static void atmel_aes_get_cap(struct atmel_aes_dev *dd)
case 0x500:
dd->caps.has_dualbuff = 1;
dd->caps.has_cfb64 = 1;
+ dd->caps.has_ctr32 = 1;
dd->caps.max_burst_size = 4;
break;
case 0x200:
dd->caps.has_dualbuff = 1;
dd->caps.has_cfb64 = 1;
+ dd->caps.has_ctr32 = 1;
dd->caps.max_burst_size = 4;
break;
case 0x130: