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Subject[PATCH v9 5/7] crypto: hisilicon/hpre - add 'ECDH' algorithm
Date
1. Enable 'ECDH' algorithm in Kunpeng 930;
2. HPRE ECDH Support: ecdh-nist-p192, ecdh-nist-p256.

Signed-off-by: Meng Yu <yumeng18@huawei.com>
Reviewed-by: Zaibo Xu <xuzaibo@huawei.com>
---
drivers/crypto/hisilicon/hpre/hpre.h | 2 +-
drivers/crypto/hisilicon/hpre/hpre_crypto.c | 515 +++++++++++++++++++++++++++-
drivers/crypto/hisilicon/hpre/hpre_main.c | 1 +
3 files changed, 513 insertions(+), 5 deletions(-)

diff --git a/drivers/crypto/hisilicon/hpre/hpre.h b/drivers/crypto/hisilicon/hpre/hpre.h
index 02193e1..50e6b2e 100644
--- a/drivers/crypto/hisilicon/hpre/hpre.h
+++ b/drivers/crypto/hisilicon/hpre/hpre.h
@@ -83,6 +83,7 @@ enum hpre_alg_type {
HPRE_ALG_KG_CRT = 0x3,
HPRE_ALG_DH_G2 = 0x4,
HPRE_ALG_DH = 0x5,
+ HPRE_ALG_ECC_MUL = 0xD,
};

struct hpre_sqe {
@@ -104,5 +105,4 @@ struct hisi_qp *hpre_create_qp(u8 type);
int hpre_algs_register(struct hisi_qm *qm);
void hpre_algs_unregister(struct hisi_qm *qm);

-
#endif
diff --git a/drivers/crypto/hisilicon/hpre/hpre_crypto.c b/drivers/crypto/hisilicon/hpre/hpre_crypto.c
index 712bea9..a6010b1 100644
--- a/drivers/crypto/hisilicon/hpre/hpre_crypto.c
+++ b/drivers/crypto/hisilicon/hpre/hpre_crypto.c
@@ -2,6 +2,8 @@
/* Copyright (c) 2019 HiSilicon Limited. */
#include <crypto/akcipher.h>
#include <crypto/dh.h>
+#include <crypto/ecc_curve.h>
+#include <crypto/ecdh.h>
#include <crypto/internal/akcipher.h>
#include <crypto/internal/kpp.h>
#include <crypto/internal/rsa.h>
@@ -36,6 +38,13 @@ struct hpre_ctx;
#define HPRE_DFX_SEC_TO_US 1000000
#define HPRE_DFX_US_TO_NS 1000

+/* size in bytes of the n prime */
+#define HPRE_ECC_NIST_P192_N_SIZE 24
+#define HPRE_ECC_NIST_P256_N_SIZE 32
+
+/* size in bytes */
+#define HPRE_ECC_HW256_KSZ_B 32
+
typedef void (*hpre_cb)(struct hpre_ctx *ctx, void *sqe);

struct hpre_rsa_ctx {
@@ -61,14 +70,25 @@ struct hpre_dh_ctx {
* else if base if the counterpart public key we
* compute the shared secret
* ZZ = yb^xa mod p; [RFC2631 sec 2.1.1]
+ * low address: d--->n, please refer to Hisilicon HPRE UM
*/
- char *xa_p; /* low address: d--->n, please refer to Hisilicon HPRE UM */
+ char *xa_p;
dma_addr_t dma_xa_p;

char *g; /* m */
dma_addr_t dma_g;
};

+struct hpre_ecdh_ctx {
+ /* low address: p->a->k->b */
+ unsigned char *p;
+ dma_addr_t dma_p;
+
+ /* low address: x->y */
+ unsigned char *g;
+ dma_addr_t dma_g;
+};
+
struct hpre_ctx {
struct hisi_qp *qp;
struct hpre_asym_request **req_list;
@@ -80,7 +100,10 @@ struct hpre_ctx {
union {
struct hpre_rsa_ctx rsa;
struct hpre_dh_ctx dh;
+ struct hpre_ecdh_ctx ecdh;
};
+ /* for ecc algorithms */
+ unsigned int curve_id;
};

struct hpre_asym_request {
@@ -91,6 +114,7 @@ struct hpre_asym_request {
union {
struct akcipher_request *rsa;
struct kpp_request *dh;
+ struct kpp_request *ecdh;
} areq;
int err;
int req_id;
@@ -1115,6 +1139,416 @@ static void hpre_rsa_exit_tfm(struct crypto_akcipher *tfm)
crypto_free_akcipher(ctx->rsa.soft_tfm);
}

+static void hpre_key_to_big_end(u8 *data, int len)
+{
+ int i, j;
+ u8 tmp;
+
+ for (i = 0; i < len / 2; i++) {
+ j = len - i - 1;
+ tmp = data[j];
+ data[j] = data[i];
+ data[i] = tmp;
+ }
+}
+
+static void hpre_ecc_clear_ctx(struct hpre_ctx *ctx, bool is_clear_all,
+ bool is_ecdh)
+{
+ struct device *dev = HPRE_DEV(ctx);
+ unsigned int sz = ctx->key_sz;
+ unsigned int shift = sz << 1;
+
+ if (is_clear_all)
+ hisi_qm_stop_qp(ctx->qp);
+
+ if (is_ecdh && ctx->ecdh.p) {
+ /* ecdh: p->a->k->b */
+ memzero_explicit(ctx->ecdh.p + shift, sz);
+ dma_free_coherent(dev, sz << 3, ctx->ecdh.p, ctx->ecdh.dma_p);
+ ctx->ecdh.p = NULL;
+ }
+
+ hpre_ctx_clear(ctx, is_clear_all);
+}
+
+static unsigned int hpre_ecdh_supported_curve(unsigned short id)
+{
+ switch (id) {
+ case ECC_CURVE_NIST_P192:
+ case ECC_CURVE_NIST_P256:
+ return HPRE_ECC_HW256_KSZ_B;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static void fill_curve_param(void *addr, u64 *param, unsigned int cur_sz, u8 ndigits)
+{
+ unsigned int sz = cur_sz - (ndigits - 1) * sizeof(u64);
+ u8 i = 0;
+
+ while (i < ndigits - 1) {
+ memcpy(addr + sizeof(u64) * i, &param[i], sizeof(u64));
+ i++;
+ }
+
+ memcpy(addr + sizeof(u64) * i, &param[ndigits - 1], sz);
+ hpre_key_to_big_end((u8 *)addr, cur_sz);
+}
+
+static int hpre_ecdh_fill_curve(struct hpre_ctx *ctx, struct ecdh *params,
+ unsigned int cur_sz)
+{
+ unsigned int shifta = ctx->key_sz << 1;
+ unsigned int shiftb = ctx->key_sz << 2;
+ void *p = ctx->ecdh.p + ctx->key_sz - cur_sz;
+ void *a = ctx->ecdh.p + shifta - cur_sz;
+ void *b = ctx->ecdh.p + shiftb - cur_sz;
+ void *x = ctx->ecdh.g + ctx->key_sz - cur_sz;
+ void *y = ctx->ecdh.g + shifta - cur_sz;
+ const struct ecc_curve *curve = ecc_get_curve(ctx->curve_id);
+ char *n;
+
+ if (unlikely(!curve))
+ return -EINVAL;
+
+ n = kzalloc(ctx->key_sz, GFP_KERNEL);
+ if (!n)
+ return -ENOMEM;
+
+ fill_curve_param(p, curve->p, cur_sz, curve->g.ndigits);
+ fill_curve_param(a, curve->a, cur_sz, curve->g.ndigits);
+ fill_curve_param(b, curve->b, cur_sz, curve->g.ndigits);
+ fill_curve_param(x, curve->g.x, cur_sz, curve->g.ndigits);
+ fill_curve_param(y, curve->g.y, cur_sz, curve->g.ndigits);
+ fill_curve_param(n, curve->n, cur_sz, curve->g.ndigits);
+
+ if (params->key_size == cur_sz && memcmp(params->key, n, cur_sz) >= 0) {
+ kfree(n);
+ return -EINVAL;
+ }
+
+ kfree(n);
+ return 0;
+}
+
+static unsigned int hpre_ecdh_get_curvesz(unsigned short id)
+{
+ switch (id) {
+ case ECC_CURVE_NIST_P192:
+ return HPRE_ECC_NIST_P192_N_SIZE;
+ case ECC_CURVE_NIST_P256:
+ return HPRE_ECC_NIST_P256_N_SIZE;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static int hpre_ecdh_set_param(struct hpre_ctx *ctx, struct ecdh *params)
+{
+ struct device *dev = HPRE_DEV(ctx);
+ unsigned int sz, shift, curve_sz;
+ int ret;
+
+ ctx->key_sz = hpre_ecdh_supported_curve(ctx->curve_id);
+ if (!ctx->key_sz)
+ return -EINVAL;
+
+ curve_sz = hpre_ecdh_get_curvesz(ctx->curve_id);
+ if (!curve_sz || params->key_size > curve_sz)
+ return -EINVAL;
+
+ sz = ctx->key_sz;
+
+ if (!ctx->ecdh.p) {
+ ctx->ecdh.p = dma_alloc_coherent(dev, sz << 3, &ctx->ecdh.dma_p,
+ GFP_KERNEL);
+ if (!ctx->ecdh.p)
+ return -ENOMEM;
+ }
+
+ shift = sz << 2;
+ ctx->ecdh.g = ctx->ecdh.p + shift;
+ ctx->ecdh.dma_g = ctx->ecdh.dma_p + shift;
+
+ ret = hpre_ecdh_fill_curve(ctx, params, curve_sz);
+ if (ret) {
+ dev_err(dev, "failed to fill curve_param, ret = %d!\n", ret);
+ dma_free_coherent(dev, sz << 3, ctx->ecdh.p, ctx->ecdh.dma_p);
+ ctx->ecdh.p = NULL;
+ return ret;
+ }
+
+ return 0;
+}
+
+static bool hpre_key_is_zero(char *key, unsigned short key_sz)
+{
+ int i;
+
+ for (i = 0; i < key_sz; i++)
+ if (key[i])
+ return false;
+
+ return true;
+}
+
+static int hpre_ecdh_set_secret(struct crypto_kpp *tfm, const void *buf,
+ unsigned int len)
+{
+ struct hpre_ctx *ctx = kpp_tfm_ctx(tfm);
+ struct device *dev = HPRE_DEV(ctx);
+ unsigned int sz, sz_shift;
+ struct ecdh params;
+ int ret;
+
+ if (crypto_ecdh_decode_key(buf, len, &params) < 0) {
+ dev_err(dev, "failed to decode ecdh key!\n");
+ return -EINVAL;
+ }
+
+ if (hpre_key_is_zero(params.key, params.key_size)) {
+ dev_err(dev, "Invalid hpre key!\n");
+ return -EINVAL;
+ }
+
+ hpre_ecc_clear_ctx(ctx, false, true);
+
+ ret = hpre_ecdh_set_param(ctx, &params);
+ if (ret < 0) {
+ dev_err(dev, "failed to set hpre param, ret = %d!\n", ret);
+ return ret;
+ }
+
+ sz = ctx->key_sz;
+ sz_shift = (sz << 1) + sz - params.key_size;
+ memcpy(ctx->ecdh.p + sz_shift, params.key, params.key_size);
+
+ return 0;
+}
+
+static void hpre_ecdh_hw_data_clr_all(struct hpre_ctx *ctx,
+ struct hpre_asym_request *req,
+ struct scatterlist *dst,
+ struct scatterlist *src)
+{
+ struct device *dev = HPRE_DEV(ctx);
+ struct hpre_sqe *sqe = &req->req;
+ dma_addr_t dma;
+
+ dma = le64_to_cpu(sqe->in);
+ if (unlikely(!dma))
+ return;
+
+ if (src && req->src)
+ dma_free_coherent(dev, ctx->key_sz << 2, req->src, dma);
+
+ dma = le64_to_cpu(sqe->out);
+ if (unlikely(!dma))
+ return;
+
+ if (req->dst)
+ dma_free_coherent(dev, ctx->key_sz << 1, req->dst, dma);
+ if (dst)
+ dma_unmap_single(dev, dma, ctx->key_sz << 1, DMA_FROM_DEVICE);
+}
+
+static void hpre_ecdh_cb(struct hpre_ctx *ctx, void *resp)
+{
+ unsigned int curve_sz = hpre_ecdh_get_curvesz(ctx->curve_id);
+ struct hpre_dfx *dfx = ctx->hpre->debug.dfx;
+ struct hpre_asym_request *req = NULL;
+ struct kpp_request *areq;
+ u64 overtime_thrhld;
+ char *p;
+ int ret;
+
+ ret = hpre_alg_res_post_hf(ctx, resp, (void **)&req);
+ areq = req->areq.ecdh;
+ areq->dst_len = ctx->key_sz << 1;
+
+ overtime_thrhld = atomic64_read(&dfx[HPRE_OVERTIME_THRHLD].value);
+ if (overtime_thrhld && hpre_is_bd_timeout(req, overtime_thrhld))
+ atomic64_inc(&dfx[HPRE_OVER_THRHLD_CNT].value);
+
+ p = sg_virt(areq->dst);
+ memmove(p, p + ctx->key_sz - curve_sz, curve_sz);
+ memmove(p + curve_sz, p + areq->dst_len - curve_sz, curve_sz);
+
+ hpre_ecdh_hw_data_clr_all(ctx, req, areq->dst, areq->src);
+ kpp_request_complete(areq, ret);
+
+ atomic64_inc(&dfx[HPRE_RECV_CNT].value);
+}
+
+static int hpre_ecdh_msg_request_set(struct hpre_ctx *ctx,
+ struct kpp_request *req)
+{
+ struct hpre_asym_request *h_req;
+ struct hpre_sqe *msg;
+ int req_id;
+ void *tmp;
+
+ if (req->dst_len < ctx->key_sz << 1) {
+ req->dst_len = ctx->key_sz << 1;
+ return -EINVAL;
+ }
+
+ tmp = kpp_request_ctx(req);
+ h_req = PTR_ALIGN(tmp, HPRE_ALIGN_SZ);
+ h_req->cb = hpre_ecdh_cb;
+ h_req->areq.ecdh = req;
+ msg = &h_req->req;
+ memset(msg, 0, sizeof(*msg));
+ msg->key = cpu_to_le64(ctx->ecdh.dma_p);
+
+ msg->dw0 |= cpu_to_le32(0x1U << HPRE_SQE_DONE_SHIFT);
+ msg->task_len1 = (ctx->key_sz >> HPRE_BITS_2_BYTES_SHIFT) - 1;
+ h_req->ctx = ctx;
+
+ req_id = hpre_add_req_to_ctx(h_req);
+ if (req_id < 0)
+ return -EBUSY;
+
+ msg->tag = cpu_to_le16((u16)req_id);
+ return 0;
+}
+
+static int hpre_ecdh_src_data_init(struct hpre_asym_request *hpre_req,
+ struct scatterlist *data, unsigned int len)
+{
+ struct hpre_sqe *msg = &hpre_req->req;
+ struct hpre_ctx *ctx = hpre_req->ctx;
+ struct device *dev = HPRE_DEV(ctx);
+ unsigned int tmpshift;
+ dma_addr_t dma = 0;
+ void *ptr;
+ int shift;
+
+ /* Src_data include gx and gy. */
+ shift = ctx->key_sz - (len >> 1);
+ if (unlikely(shift < 0))
+ return -EINVAL;
+
+ ptr = dma_alloc_coherent(dev, ctx->key_sz << 2, &dma, GFP_KERNEL);
+ if (unlikely(!ptr))
+ return -ENOMEM;
+
+ tmpshift = ctx->key_sz << 1;
+ scatterwalk_map_and_copy(ptr + tmpshift, data, 0, len, 0);
+ memcpy(ptr + shift, ptr + tmpshift, len >> 1);
+ memcpy(ptr + ctx->key_sz + shift, ptr + tmpshift + (len >> 1), len >> 1);
+
+ hpre_req->src = ptr;
+ msg->in = cpu_to_le64(dma);
+ return 0;
+}
+
+static int hpre_ecdh_dst_data_init(struct hpre_asym_request *hpre_req,
+ struct scatterlist *data, unsigned int len)
+{
+ struct hpre_sqe *msg = &hpre_req->req;
+ struct hpre_ctx *ctx = hpre_req->ctx;
+ struct device *dev = HPRE_DEV(ctx);
+ dma_addr_t dma = 0;
+
+ if (unlikely(!data || !sg_is_last(data) || len != ctx->key_sz << 1)) {
+ dev_err(dev, "data or data length is illegal!\n");
+ return -EINVAL;
+ }
+
+ hpre_req->dst = NULL;
+ dma = dma_map_single(dev, sg_virt(data), len, DMA_FROM_DEVICE);
+ if (unlikely(dma_mapping_error(dev, dma))) {
+ dev_err(dev, "dma map data err!\n");
+ return -ENOMEM;
+ }
+
+ msg->out = cpu_to_le64(dma);
+ return 0;
+}
+
+static int hpre_ecdh_compute_value(struct kpp_request *req)
+{
+ struct crypto_kpp *tfm = crypto_kpp_reqtfm(req);
+ struct hpre_ctx *ctx = kpp_tfm_ctx(tfm);
+ struct device *dev = HPRE_DEV(ctx);
+ void *tmp = kpp_request_ctx(req);
+ struct hpre_asym_request *hpre_req = PTR_ALIGN(tmp, HPRE_ALIGN_SZ);
+ struct hpre_sqe *msg = &hpre_req->req;
+ int ret;
+
+ ret = hpre_ecdh_msg_request_set(ctx, req);
+ if (unlikely(ret)) {
+ dev_err(dev, "failed to set ecdh request, ret = %d!\n", ret);
+ return ret;
+ }
+
+ if (req->src) {
+ ret = hpre_ecdh_src_data_init(hpre_req, req->src, req->src_len);
+ if (unlikely(ret)) {
+ dev_err(dev, "failed to init src data, ret = %d!\n", ret);
+ goto clear_all;
+ }
+ } else {
+ msg->in = cpu_to_le64(ctx->ecdh.dma_g);
+ }
+
+ ret = hpre_ecdh_dst_data_init(hpre_req, req->dst, req->dst_len);
+ if (unlikely(ret)) {
+ dev_err(dev, "failed to init dst data, ret = %d!\n", ret);
+ goto clear_all;
+ }
+
+ msg->dw0 = cpu_to_le32(le32_to_cpu(msg->dw0) | HPRE_ALG_ECC_MUL);
+ ret = hpre_send(ctx, msg);
+ if (likely(!ret))
+ return -EINPROGRESS;
+
+clear_all:
+ hpre_rm_req_from_ctx(hpre_req);
+ hpre_ecdh_hw_data_clr_all(ctx, hpre_req, req->dst, req->src);
+ return ret;
+}
+
+static unsigned int hpre_ecdh_max_size(struct crypto_kpp *tfm)
+{
+ struct hpre_ctx *ctx = kpp_tfm_ctx(tfm);
+
+ /* max size is the pub_key_size, include x and y */
+ return ctx->key_sz << 1;
+}
+
+static int hpre_ecdh_nist_p192_init_tfm(struct crypto_kpp *tfm)
+{
+ struct hpre_ctx *ctx = kpp_tfm_ctx(tfm);
+
+ ctx->curve_id = ECC_CURVE_NIST_P192;
+
+ return hpre_ctx_init(ctx, HPRE_V3_ECC_ALG_TYPE);
+}
+
+static int hpre_ecdh_nist_p256_init_tfm(struct crypto_kpp *tfm)
+{
+ struct hpre_ctx *ctx = kpp_tfm_ctx(tfm);
+
+ ctx->curve_id = ECC_CURVE_NIST_P256;
+
+ return hpre_ctx_init(ctx, HPRE_V3_ECC_ALG_TYPE);
+}
+
+static void hpre_ecdh_exit_tfm(struct crypto_kpp *tfm)
+{
+ struct hpre_ctx *ctx = kpp_tfm_ctx(tfm);
+
+ hpre_ecc_clear_ctx(ctx, true, true);
+}
+
static struct akcipher_alg rsa = {
.sign = hpre_rsa_dec,
.verify = hpre_rsa_enc,
@@ -1154,6 +1588,63 @@ static struct kpp_alg dh = {
};
#endif

+static struct kpp_alg ecdh_nist_p192 = {
+ .set_secret = hpre_ecdh_set_secret,
+ .generate_public_key = hpre_ecdh_compute_value,
+ .compute_shared_secret = hpre_ecdh_compute_value,
+ .max_size = hpre_ecdh_max_size,
+ .init = hpre_ecdh_nist_p192_init_tfm,
+ .exit = hpre_ecdh_exit_tfm,
+ .reqsize = sizeof(struct hpre_asym_request) + HPRE_ALIGN_SZ,
+ .base = {
+ .cra_ctxsize = sizeof(struct hpre_ctx),
+ .cra_priority = HPRE_CRYPTO_ALG_PRI,
+ .cra_name = "ecdh-nist-p192",
+ .cra_driver_name = "hpre-ecdh",
+ .cra_module = THIS_MODULE,
+ },
+};
+
+static struct kpp_alg ecdh_nist_p256 = {
+ .set_secret = hpre_ecdh_set_secret,
+ .generate_public_key = hpre_ecdh_compute_value,
+ .compute_shared_secret = hpre_ecdh_compute_value,
+ .max_size = hpre_ecdh_max_size,
+ .init = hpre_ecdh_nist_p256_init_tfm,
+ .exit = hpre_ecdh_exit_tfm,
+ .reqsize = sizeof(struct hpre_asym_request) + HPRE_ALIGN_SZ,
+ .base = {
+ .cra_ctxsize = sizeof(struct hpre_ctx),
+ .cra_priority = HPRE_CRYPTO_ALG_PRI,
+ .cra_name = "ecdh-nist-p256",
+ .cra_driver_name = "hpre-ecdh",
+ .cra_module = THIS_MODULE,
+ },
+};
+
+static int hpre_register_ecdh(void)
+{
+ int ret;
+
+ ret = crypto_register_kpp(&ecdh_nist_p192);
+ if (ret)
+ return ret;
+
+ ret = crypto_register_kpp(&ecdh_nist_p256);
+ if (ret) {
+ crypto_unregister_kpp(&ecdh_nist_p192);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void hpre_unregister_ecdh(void)
+{
+ crypto_unregister_kpp(&ecdh_nist_p256);
+ crypto_unregister_kpp(&ecdh_nist_p192);
+}
+
int hpre_algs_register(struct hisi_qm *qm)
{
int ret;
@@ -1164,17 +1655,33 @@ int hpre_algs_register(struct hisi_qm *qm)
return ret;
#ifdef CONFIG_CRYPTO_DH
ret = crypto_register_kpp(&dh);
- if (ret)
+ if (ret) {
crypto_unregister_akcipher(&rsa);
+ return ret;
+ }
#endif

- return ret;
+ if (qm->ver >= QM_HW_V3) {
+ ret = hpre_register_ecdh();
+ if (ret) {
+#ifdef CONFIG_CRYPTO_DH
+ crypto_unregister_kpp(&dh);
+#endif
+ crypto_unregister_akcipher(&rsa);
+ return ret;
+ }
+ }
+
+ return 0;
}

void hpre_algs_unregister(struct hisi_qm *qm)
{
- crypto_unregister_akcipher(&rsa);
+ if (qm->ver >= QM_HW_V3)
+ hpre_unregister_ecdh();
+
#ifdef CONFIG_CRYPTO_DH
crypto_unregister_kpp(&dh);
#endif
+ crypto_unregister_akcipher(&rsa);
}
diff --git a/drivers/crypto/hisilicon/hpre/hpre_main.c b/drivers/crypto/hisilicon/hpre/hpre_main.c
index 76f0a87..87e8f4d 100644
--- a/drivers/crypto/hisilicon/hpre/hpre_main.c
+++ b/drivers/crypto/hisilicon/hpre/hpre_main.c
@@ -1082,4 +1082,5 @@ module_exit(hpre_exit);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Zaibo Xu <xuzaibo@huawei.com>");
+MODULE_AUTHOR("Meng Yu <yumeng18@huawei.com>");
MODULE_DESCRIPTION("Driver for HiSilicon HPRE accelerator");
--
2.8.1
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