[PATCH V3 4/4] crypto: Add Xilinx AES driver

Kalyani Akula
2019-11-06T11:41:01Z

This patch adds AES driver support for the Xilinx ZynqMP SoC.

Signed-off-by: Kalyani Akula <kalyani.akula@xilinx.com>
---
drivers/crypto/Kconfig | 11 +
drivers/crypto/Makefile | 2 +
drivers/crypto/xilinx/Makefile | 3 +
drivers/crypto/xilinx/zynqmp-aes-gcm.c | 457 +++++++++++++++++++++++++++++++++
4 files changed, 473 insertions(+)
create mode 100644 drivers/crypto/xilinx/Makefile
create mode 100644 drivers/crypto/xilinx/zynqmp-aes-gcm.c

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 1fb622f..8e7d3a9 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -696,6 +696,17 @@ config CRYPTO_DEV_ROCKCHIP
help
This driver interfaces with the hardware crypto accelerator.
Supporting cbc/ecb chainmode, and aes/des/des3_ede cipher mode.
+config CRYPTO_DEV_ZYNQMP_AES
+ tristate "Support for Xilinx ZynqMP AES hw accelerator"
+ depends on ARCH_ZYNQMP || COMPILE_TEST
+ select CRYPTO_AES
+ select CRYPTO_ENGINE
+ select CRYPTO_AEAD
+ help
+ Xilinx ZynqMP has AES-GCM engine used for symmetric key
+ encryption and decryption. This driver interfaces with AES hw
+ accelerator. Select this if you want to use the ZynqMP module
+ for AES algorithms.

config CRYPTO_DEV_MEDIATEK
tristate "MediaTek's EIP97 Cryptographic Engine driver"
diff --git a/drivers/crypto/Makefile b/drivers/crypto/Makefile
index afc4753..b6124b8 100644
--- a/drivers/crypto/Makefile
+++ b/drivers/crypto/Makefile
@@ -47,4 +47,6 @@ obj-$(CONFIG_CRYPTO_DEV_VMX) += vmx/
obj-$(CONFIG_CRYPTO_DEV_BCM_SPU) += bcm/
obj-$(CONFIG_CRYPTO_DEV_SAFEXCEL) += inside-secure/
obj-$(CONFIG_CRYPTO_DEV_ARTPEC6) += axis/
+obj-$(CONFIG_CRYPTO_DEV_ZYNQMP_AES) += xilinx/
+
obj-y += hisilicon/
diff --git a/drivers/crypto/xilinx/Makefile b/drivers/crypto/xilinx/Makefile
new file mode 100644
index 0000000..16bdda7
--- /dev/null
+++ b/drivers/crypto/xilinx/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_CRYPTO_DEV_ZYNQMP_AES) += zynqmp-aes-gcm.o
+
diff --git a/drivers/crypto/xilinx/zynqmp-aes-gcm.c b/drivers/crypto/xilinx/zynqmp-aes-gcm.c
new file mode 100644
index 0000000..fe2ba8d
--- /dev/null
+++ b/drivers/crypto/xilinx/zynqmp-aes-gcm.c
@@ -0,0 +1,457 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx ZynqMP AES Driver.
+ * Copyright (c) 2018 Xilinx Inc.
+ */
+
+#include <crypto/aes.h>
+#include <crypto/engine.h>
+#include <crypto/gcm.h>
+#include <crypto/internal/aead.h>
+#include <crypto/scatterwalk.h>
+
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+#include <linux/firmware/xlnx-zynqmp.h>
+
+#define DRIVER_NAME "zynqmp-aes"
+#define ZYNQMP_DMA_BIT_MASK 32U
+
+#define ZYNQMP_AES_KEY_SIZE AES_KEYSIZE_256
+#define ZYNQMP_AES_AUTH_SIZE 16U
+#define ZYNQMP_KEY_SRC_SEL_KEY_LEN 1U
+#define ZYNQMP_AES_BLK_SIZE 1U
+#define ZYNQMP_AES_MIN_INPUT_BLK_SIZE 4U
+#define ZYNQMP_AES_WORD_LEN 4U
+
+#define ZYNQMP_AES_GCM_TAG_MISMATCH_ERR 0x01
+#define ZYNQMP_AES_WRONG_KEY_SRC_ERR 0x13
+#define ZYNQMP_AES_PUF_NOT_PROGRAMMED 0xE300
+
+enum zynqmp_aead_op {
+ ZYNQMP_AES_DECRYPT = 0,
+ ZYNQMP_AES_ENCRYPT
+};
+
+enum zynqmp_aead_keysrc {
+ ZYNQMP_AES_KUP_KEY = 0,
+ ZYNQMP_AES_DEV_KEY,
+ ZYNQMP_AES_PUF_KEY
+};
+
+struct zynqmp_aead_drv_ctx {
+ union {
+ struct aead_alg aead;
+ } alg;
+ struct device *dev;
+ struct crypto_engine *engine;
+ const struct zynqmp_eemi_ops *eemi_ops;
+};
+
+struct zynqmp_aead_hw_req {
+ u64 src;
+ u64 iv;
+ u64 key;
+ u64 dst;
+ u64 size;
+ u64 op;
+ u64 keysrc;
+};
+
+struct zynqmp_aead_tfm_ctx {
+ struct crypto_engine_ctx engine_ctx;
+ struct device *dev;
+ u8 key[ZYNQMP_AES_KEY_SIZE];
+ u8 *iv;
+ u32 keylen;
+ u32 authsize;
+ enum zynqmp_aead_keysrc keysrc;
+ struct crypto_aead *fbk_cipher;
+};
+
+struct zynqmp_aead_req_ctx {
+ enum zynqmp_aead_op op;
+};
+
+static int zynqmp_aes_aead_cipher(struct aead_request *req)
+{
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
+ struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
+ struct device *dev = tfm_ctx->dev;
+ struct aead_alg *alg = crypto_aead_alg(aead);
+ struct zynqmp_aead_drv_ctx *drv_ctx;
+ struct zynqmp_aead_hw_req *hwreq;
+ dma_addr_t dma_addr_data, dma_addr_hw_req;
+ unsigned int data_size;
+ unsigned int status;
+ size_t dma_size;
+ char *kbuf;
+ int err;
+
+ drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
+
+ if (!drv_ctx->eemi_ops->aes)
+ return -ENOTSUPP;
+
+ if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY)
+ dma_size = req->cryptlen + ZYNQMP_AES_KEY_SIZE
+ + GCM_AES_IV_SIZE;
+ else
+ dma_size = req->cryptlen + GCM_AES_IV_SIZE;
+
+ kbuf = dma_alloc_coherent(dev, dma_size, &dma_addr_data, GFP_KERNEL);
+ if (!kbuf)
+ return -ENOMEM;
+
+ hwreq = dma_alloc_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
+ &dma_addr_hw_req, GFP_KERNEL);
+ if (!hwreq) {
+ dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
+ return -ENOMEM;
+ }
+
+ data_size = req->cryptlen;
+ scatterwalk_map_and_copy(kbuf, req->src, 0, req->cryptlen, 0);
+ memcpy(kbuf + data_size, req->iv, GCM_AES_IV_SIZE);
+
+ hwreq->src = dma_addr_data;
+ hwreq->dst = dma_addr_data;
+ hwreq->iv = hwreq->src + data_size;
+ hwreq->keysrc = tfm_ctx->keysrc;
+ hwreq->op = rq_ctx->op;
+
+ if (hwreq->op == ZYNQMP_AES_ENCRYPT)
+ hwreq->size = data_size;
+ else
+ hwreq->size = data_size - ZYNQMP_AES_AUTH_SIZE;
+
+ if (hwreq->keysrc == ZYNQMP_AES_KUP_KEY) {
+ memcpy(kbuf + data_size + GCM_AES_IV_SIZE,
+ tfm_ctx->key, ZYNQMP_AES_KEY_SIZE);
+
+ hwreq->key = hwreq->src + data_size + GCM_AES_IV_SIZE;
+ } else {
+ hwreq->key = 0;
+ }
+
+ drv_ctx->eemi_ops->aes(dma_addr_hw_req, &status);
+
+ if (status) {
+ switch (status) {
+ case ZYNQMP_AES_GCM_TAG_MISMATCH_ERR:
+ dev_err(dev, "ERROR: Gcm Tag mismatch\n");
+ break;
+ case ZYNQMP_AES_WRONG_KEY_SRC_ERR:
+ dev_err(dev, "ERROR: Wrong KeySrc, enable secure mode\n");
+ break;
+ case ZYNQMP_AES_PUF_NOT_PROGRAMMED:
+ dev_err(dev, "ERROR: PUF is not registered\n");
+ break;
+ default:
+ dev_err(dev, "ERROR: Unknown error\n");
+ break;
+ }
+ err = -status;
+ } else {
+ if (hwreq->op == ZYNQMP_AES_ENCRYPT)
+ data_size = data_size + ZYNQMP_AES_AUTH_SIZE;
+ else
+ data_size = data_size - ZYNQMP_AES_AUTH_SIZE;
+
+ sg_copy_from_buffer(req->dst, sg_nents(req->dst),
+ kbuf, data_size);
+ err = 0;
+ }
+
+ if (kbuf) {
+ memzero_explicit(kbuf, dma_size);
+ dma_free_coherent(dev, dma_size, kbuf, dma_addr_data);
+ }
+ if (hwreq) {
+ memzero_explicit(hwreq, sizeof(struct zynqmp_aead_hw_req));
+ dma_free_coherent(dev, sizeof(struct zynqmp_aead_hw_req),
+ hwreq, dma_addr_hw_req);
+ }
+ return err;
+}
+
+static int zynqmp_fallback_check(struct zynqmp_aead_tfm_ctx *tfm_ctx,
+ struct aead_request *req)
+{
+ int need_fallback = 0;
+ struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
+
+ if (tfm_ctx->authsize != ZYNQMP_AES_AUTH_SIZE)
+ need_fallback = 1;
+
+ if (tfm_ctx->keysrc == ZYNQMP_AES_KUP_KEY &&
+ tfm_ctx->keylen != ZYNQMP_AES_KEY_SIZE) {
+ need_fallback = 1;
+ }
+ if (req->assoclen != 0 ||
+ req->cryptlen < ZYNQMP_AES_MIN_INPUT_BLK_SIZE) {
+ need_fallback = 1;
+ }
+ if ((req->cryptlen % ZYNQMP_AES_WORD_LEN) != 0)
+ need_fallback = 1;
+
+ if (rq_ctx->op == ZYNQMP_AES_DECRYPT &&
+ req->cryptlen <= ZYNQMP_AES_AUTH_SIZE) {
+ need_fallback = 1;
+ }
+ return need_fallback;
+}
+
+static int zynqmp_handle_aes_req(struct crypto_engine *engine,
+ void *req)
+{
+ struct aead_request *areq =
+ container_of(req, struct aead_request, base);
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct zynqmp_aead_tfm_ctx *tfm_ctx = crypto_aead_ctx(aead);
+ struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(areq);
+ struct aead_request *subreq;
+ int need_fallback;
+ int err;
+
+ need_fallback = zynqmp_fallback_check(tfm_ctx, areq);
+
+ if (need_fallback) {
+ subreq = aead_request_alloc(tfm_ctx->fbk_cipher, GFP_KERNEL);
+ if (!subreq)
+ return -ENOMEM;
+
+ aead_request_set_callback(subreq, areq->base.flags,
+ NULL, NULL);
+ aead_request_set_crypt(subreq, areq->src, areq->dst,
+ areq->cryptlen, areq->iv);
+ aead_request_set_ad(subreq, areq->assoclen);
+ if (rq_ctx->op == ZYNQMP_AES_ENCRYPT)
+ err = crypto_aead_encrypt(subreq);
+ else
+ err = crypto_aead_decrypt(subreq);
+ aead_request_free(subreq);
+ } else {
+ err = zynqmp_aes_aead_cipher(areq);
+ }
+
+ crypto_finalize_aead_request(engine, areq, err);
+ return 0;
+}
+
+static int zynqmp_aes_aead_setkey(struct crypto_aead *aead, const u8 *key,
+ unsigned int keylen)
+{
+ struct crypto_tfm *tfm = crypto_aead_tfm(aead);
+ struct zynqmp_aead_tfm_ctx *tfm_ctx =
+ (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
+ unsigned char keysrc;
+ int err;
+
+ if (keylen == ZYNQMP_KEY_SRC_SEL_KEY_LEN) {
+ keysrc = *key;
+ if (keysrc == ZYNQMP_AES_KUP_KEY ||
+ keysrc == ZYNQMP_AES_DEV_KEY ||
+ keysrc == ZYNQMP_AES_PUF_KEY) {
+ tfm_ctx->keysrc = (enum zynqmp_aead_keysrc)keysrc;
+ } else {
+ tfm_ctx->keylen = keylen;
+ }
+ } else {
+ tfm_ctx->keylen = keylen;
+ if (keylen == ZYNQMP_AES_KEY_SIZE) {
+ tfm_ctx->keysrc = ZYNQMP_AES_KUP_KEY;
+ memcpy(tfm_ctx->key, key, keylen);
+ }
+ }
+
+ tfm_ctx->fbk_cipher->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
+ tfm_ctx->fbk_cipher->base.crt_flags |= (aead->base.crt_flags &
+ CRYPTO_TFM_REQ_MASK);
+
+ err = crypto_aead_setkey(tfm_ctx->fbk_cipher, key, keylen);
+ if (err) {
+ aead->base.crt_flags &= ~CRYPTO_TFM_RES_MASK;
+ aead->base.crt_flags |=
+ (tfm_ctx->fbk_cipher->base.crt_flags &
+ CRYPTO_TFM_RES_MASK);
+ }
+
+ return err;
+}
+
+static int zynqmp_aes_aead_setauthsize(struct crypto_aead *aead,
+ unsigned int authsize)
+{
+ struct crypto_tfm *tfm = crypto_aead_tfm(aead);
+ struct zynqmp_aead_tfm_ctx *tfm_ctx =
+ (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
+
+ tfm_ctx->authsize = authsize;
+ return crypto_aead_setauthsize(tfm_ctx->fbk_cipher, authsize);
+}
+
+static int zynqmp_aes_aead_encrypt(struct aead_request *req)
+{
+ struct zynqmp_aead_drv_ctx *drv_ctx;
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct aead_alg *alg = crypto_aead_alg(aead);
+ struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
+
+ rq_ctx->op = ZYNQMP_AES_ENCRYPT;
+ drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
+
+ return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
+}
+
+static int zynqmp_aes_aead_decrypt(struct aead_request *req)
+{
+ struct zynqmp_aead_drv_ctx *drv_ctx;
+ struct crypto_aead *aead = crypto_aead_reqtfm(req);
+ struct aead_alg *alg = crypto_aead_alg(aead);
+ struct zynqmp_aead_req_ctx *rq_ctx = aead_request_ctx(req);
+
+ rq_ctx->op = ZYNQMP_AES_DECRYPT;
+ drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
+
+ return crypto_transfer_aead_request_to_engine(drv_ctx->engine, req);
+}
+
+static int zynqmp_aes_aead_init(struct crypto_aead *aead)
+{
+ struct crypto_tfm *tfm = crypto_aead_tfm(aead);
+ struct zynqmp_aead_tfm_ctx *tfm_ctx =
+ (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
+ struct zynqmp_aead_drv_ctx *drv_ctx;
+ struct aead_alg *alg = crypto_aead_alg(aead);
+
+ crypto_aead_set_reqsize(aead, sizeof(struct zynqmp_aead_req_ctx));
+
+ drv_ctx = container_of(alg, struct zynqmp_aead_drv_ctx, alg.aead);
+ tfm_ctx->dev = drv_ctx->dev;
+
+ tfm_ctx->engine_ctx.op.do_one_request = zynqmp_handle_aes_req;
+ tfm_ctx->engine_ctx.op.prepare_request = NULL;
+ tfm_ctx->engine_ctx.op.unprepare_request = NULL;
+
+ tfm_ctx->fbk_cipher = crypto_alloc_aead(drv_ctx->alg.aead.base.cra_name,
+ 0,
+ CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_NEED_FALLBACK);
+
+ if (IS_ERR(tfm_ctx->fbk_cipher)) {
+ pr_err("%s() Error: failed to allocate fallback for %s\n",
+ __func__, drv_ctx->alg.aead.base.cra_name);
+ return PTR_ERR(tfm_ctx->fbk_cipher);
+ }
+
+ return 0;
+}
+
+static void zynqmp_aes_aead_exit(struct crypto_aead *aead)
+{
+ struct crypto_tfm *tfm = crypto_aead_tfm(aead);
+ struct zynqmp_aead_tfm_ctx *tfm_ctx =
+ (struct zynqmp_aead_tfm_ctx *)crypto_tfm_ctx(tfm);
+
+ if (tfm_ctx->fbk_cipher) {
+ crypto_free_aead(tfm_ctx->fbk_cipher);
+ tfm_ctx->fbk_cipher = NULL;
+ }
+ memzero_explicit(tfm_ctx, sizeof(struct zynqmp_aead_tfm_ctx));
+}
+
+static struct zynqmp_aead_drv_ctx aes_drv_ctx = {
+ .alg.aead = {
+ .setkey = zynqmp_aes_aead_setkey,
+ .setauthsize = zynqmp_aes_aead_setauthsize,
+ .encrypt = zynqmp_aes_aead_encrypt,
+ .decrypt = zynqmp_aes_aead_decrypt,
+ .init = zynqmp_aes_aead_init,
+ .exit = zynqmp_aes_aead_exit,
+ .ivsize = GCM_AES_IV_SIZE,
+ .maxauthsize = ZYNQMP_AES_AUTH_SIZE,
+ .base = {
+ .cra_name = "gcm(aes)",
+ .cra_driver_name = "xilinx-zynqmp-aes-gcm",
+ .cra_priority = 200,
+ .cra_flags = CRYPTO_ALG_TYPE_AEAD |
+ CRYPTO_ALG_ASYNC |
+ CRYPTO_ALG_KERN_DRIVER_ONLY |
+ CRYPTO_ALG_NEED_FALLBACK,
+ .cra_blocksize = ZYNQMP_AES_BLK_SIZE,
+ .cra_ctxsize = sizeof(struct zynqmp_aead_tfm_ctx),
+ .cra_module = THIS_MODULE,
+ }
+ }
+};
+
+static int zynqmp_aes_aead_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int err = -1;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ aes_drv_ctx.dev = dev;
+ aes_drv_ctx.eemi_ops = zynqmp_pm_get_eemi_ops();
+ if (IS_ERR(aes_drv_ctx.eemi_ops)) {
+ dev_err(dev, "Failed to get ZynqMP EEMI interface\n");
+ return PTR_ERR(aes_drv_ctx.eemi_ops);
+ }
+
+ err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(ZYNQMP_DMA_BIT_MASK));
+ if (err < 0) {
+ dev_err(dev, "No usable DMA configuration\n");
+ return err;
+ }
+
+ aes_drv_ctx.engine = crypto_engine_alloc_init(dev, 1);
+ if (!aes_drv_ctx.engine) {
+ dev_err(dev, "Cannot alloc AES engine\n");
+ return err;
+ }
+
+ err = crypto_engine_start(aes_drv_ctx.engine);
+ if (err) {
+ dev_err(dev, "Cannot start AES engine\n");
+ return err;
+ }
+
+ err = crypto_register_aead(&aes_drv_ctx.alg.aead);
+ if (err < 0)
+ dev_err(dev, "Failed to register AEAD alg.\n");
+
+ return err;
+}
+
+static int zynqmp_aes_aead_remove(struct platform_device *pdev)
+{
+ crypto_engine_exit(aes_drv_ctx.engine);
+ crypto_unregister_aead(&aes_drv_ctx.alg.aead);
+ return 0;
+}
+
+static const struct of_device_id zynqmp_aes_dt_ids[] = {
+ { .compatible = "xlnx,zynqmp-aes" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, zynqmp_aes_dt_ids);
+
+static struct platform_driver zynqmp_aes_driver = {
+ .probe = zynqmp_aes_aead_probe,
+ .remove = zynqmp_aes_aead_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = zynqmp_aes_dt_ids,
+ },
+};
+
+module_platform_driver(zynqmp_aes_driver);
+
+MODULE_LICENSE("GPL");
+
--
1.9.5