crypto: virtio - switch to skcipher API

Commit 7a7ffe65c8c5 ("crypto: skcipher - Add top-level skcipher interface")
dated 20 august 2015 introduced the new skcipher API which is supposed to
replace both blkcipher and ablkcipher. While all consumers of the API have
been converted long ago, some producers of the ablkcipher remain, forcing
us to keep the ablkcipher support routines alive, along with the matching
code to expose [a]blkciphers via the skcipher API.

So switch this driver to the skcipher API, allowing us to finally drop the
ablkcipher code in the near future.

Cc: "Michael S. Tsirkin" <[e-mail]>
Cc: Jason Wang <[e-mail]>
Cc: Gonglei <[e-mail]>
Cc: [e-mail]
Signed-off-by: Ard Biesheuvel <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/virtio/virtio_crypto_algs.c

···
 
 #include <linux/scatterlist.h>
 #include <crypto/algapi.h>
+#include <crypto/internal/skcipher.h>
 #include <linux/err.h>
 #include <crypto/scatterwalk.h>
 #include <linux/atomic.h>
···
 #include "virtio_crypto_common.h"
 
 
-struct virtio_crypto_ablkcipher_ctx {
+struct virtio_crypto_skcipher_ctx {
 	struct crypto_engine_ctx enginectx;
 	struct virtio_crypto *vcrypto;
-	struct crypto_tfm *tfm;
+	struct crypto_skcipher *tfm;
 
 	struct virtio_crypto_sym_session_info enc_sess_info;
 	struct virtio_crypto_sym_session_info dec_sess_info;
···
 
 	/* Cipher or aead */
 	uint32_t type;
-	struct virtio_crypto_ablkcipher_ctx *ablkcipher_ctx;
-	struct ablkcipher_request *ablkcipher_req;
+	struct virtio_crypto_skcipher_ctx *skcipher_ctx;
+	struct skcipher_request *skcipher_req;
 	uint8_t *iv;
 	/* Encryption? */
 	bool encrypt;
···
 	uint32_t algonum;
 	uint32_t service;
 	unsigned int active_devs;
-	struct crypto_alg algo;
+	struct skcipher_alg algo;
 };
 
 /*
···
  * and crypto algorithms registion.
  */
 static DEFINE_MUTEX(algs_lock);
-static void virtio_crypto_ablkcipher_finalize_req(
+static void virtio_crypto_skcipher_finalize_req(
 	struct virtio_crypto_sym_request *vc_sym_req,
-	struct ablkcipher_request *req,
+	struct skcipher_request *req,
 	int err);
 
 static void virtio_crypto_dataq_sym_callback
···
 {
 	struct virtio_crypto_sym_request *vc_sym_req =
 		container_of(vc_req, struct virtio_crypto_sym_request, base);
-	struct ablkcipher_request *ablk_req;
+	struct skcipher_request *ablk_req;
 	int error;
 
 	/* Finish the encrypt or decrypt process */
···
 			error = -EIO;
 			break;
 		}
-		ablk_req = vc_sym_req->ablkcipher_req;
-		virtio_crypto_ablkcipher_finalize_req(vc_sym_req,
+		ablk_req = vc_sym_req->skcipher_req;
+		virtio_crypto_skcipher_finalize_req(vc_sym_req,
 							ablk_req, error);
 	}
 }
···
 	return 0;
 }
 
-static int virtio_crypto_alg_ablkcipher_init_session(
-		struct virtio_crypto_ablkcipher_ctx *ctx,
+static int virtio_crypto_alg_skcipher_init_session(
+		struct virtio_crypto_skcipher_ctx *ctx,
 		uint32_t alg, const uint8_t *key,
 		unsigned int keylen,
 		int encrypt)
···
 	return 0;
 }
 
-static int virtio_crypto_alg_ablkcipher_close_session(
-		struct virtio_crypto_ablkcipher_ctx *ctx,
+static int virtio_crypto_alg_skcipher_close_session(
+		struct virtio_crypto_skcipher_ctx *ctx,
 		int encrypt)
 {
 	struct scatterlist outhdr, status_sg, *sgs[2];
···
 	return 0;
 }
 
-static int virtio_crypto_alg_ablkcipher_init_sessions(
-		struct virtio_crypto_ablkcipher_ctx *ctx,
+static int virtio_crypto_alg_skcipher_init_sessions(
+		struct virtio_crypto_skcipher_ctx *ctx,
 		const uint8_t *key, unsigned int keylen)
 {
 	uint32_t alg;
···
 		goto bad_key;
 
 	/* Create encryption session */
-	ret = virtio_crypto_alg_ablkcipher_init_session(ctx,
+	ret = virtio_crypto_alg_skcipher_init_session(ctx,
 			alg, key, keylen, 1);
 	if (ret)
 		return ret;
 	/* Create decryption session */
-	ret = virtio_crypto_alg_ablkcipher_init_session(ctx,
+	ret = virtio_crypto_alg_skcipher_init_session(ctx,
 			alg, key, keylen, 0);
 	if (ret) {
-		virtio_crypto_alg_ablkcipher_close_session(ctx, 1);
+		virtio_crypto_alg_skcipher_close_session(ctx, 1);
 		return ret;
 	}
 	return 0;
 
 bad_key:
-	crypto_tfm_set_flags(ctx->tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
+	crypto_skcipher_set_flags(ctx->tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 	return -EINVAL;
 }
 
 /* Note: kernel crypto API realization */
-static int virtio_crypto_ablkcipher_setkey(struct crypto_ablkcipher *tfm,
+static int virtio_crypto_skcipher_setkey(struct crypto_skcipher *tfm,
 					 const uint8_t *key,
 					 unsigned int keylen)
 {
-	struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 	uint32_t alg;
 	int ret;
 
···
 		ctx->vcrypto = vcrypto;
 	} else {
 		/* Rekeying, we should close the created sessions previously */
-		virtio_crypto_alg_ablkcipher_close_session(ctx, 1);
-		virtio_crypto_alg_ablkcipher_close_session(ctx, 0);
+		virtio_crypto_alg_skcipher_close_session(ctx, 1);
+		virtio_crypto_alg_skcipher_close_session(ctx, 0);
 	}
 
-	ret = virtio_crypto_alg_ablkcipher_init_sessions(ctx, key, keylen);
+	ret = virtio_crypto_alg_skcipher_init_sessions(ctx, key, keylen);
 	if (ret) {
 		virtcrypto_dev_put(ctx->vcrypto);
 		ctx->vcrypto = NULL;
···
 }
 
 static int
-__virtio_crypto_ablkcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
-		struct ablkcipher_request *req,
+__virtio_crypto_skcipher_do_req(struct virtio_crypto_sym_request *vc_sym_req,
+		struct skcipher_request *req,
 		struct data_queue *data_vq)
 {
-	struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
-	struct virtio_crypto_ablkcipher_ctx *ctx = vc_sym_req->ablkcipher_ctx;
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	struct virtio_crypto_skcipher_ctx *ctx = vc_sym_req->skcipher_ctx;
 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
-	unsigned int ivsize = crypto_ablkcipher_ivsize(tfm);
+	unsigned int ivsize = crypto_skcipher_ivsize(tfm);
 	struct virtio_crypto *vcrypto = ctx->vcrypto;
 	struct virtio_crypto_op_data_req *req_data;
 	int src_nents, dst_nents;
···
 	int sg_total;
 	uint8_t *iv;
 
-	src_nents = sg_nents_for_len(req->src, req->nbytes);
+	src_nents = sg_nents_for_len(req->src, req->cryptlen);
 	dst_nents = sg_nents(req->dst);
 
 	pr_debug("virtio_crypto: Number of sgs (src_nents: %d, dst_nents: %d)\n",
···
 	req_data->u.sym_req.op_type = cpu_to_le32(VIRTIO_CRYPTO_SYM_OP_CIPHER);
 	req_data->u.sym_req.u.cipher.para.iv_len = cpu_to_le32(ivsize);
 	req_data->u.sym_req.u.cipher.para.src_data_len =
-			cpu_to_le32(req->nbytes);
+			cpu_to_le32(req->cryptlen);
 
 	dst_len = virtio_crypto_alg_sg_nents_length(req->dst);
 	if (unlikely(dst_len > U32_MAX)) {
···
 	}
 
 	pr_debug("virtio_crypto: src_len: %u, dst_len: %llu\n",
-			req->nbytes, dst_len);
+			req->cryptlen, dst_len);
 
-	if (unlikely(req->nbytes + dst_len + ivsize +
+	if (unlikely(req->cryptlen + dst_len + ivsize +
 		sizeof(vc_req->status) > vcrypto->max_size)) {
 		pr_err("virtio_crypto: The length is too big\n");
 		err = -EINVAL;
···
 		err = -ENOMEM;
 		goto free;
 	}
-	memcpy(iv, req->info, ivsize);
+	memcpy(iv, req->iv, ivsize);
 	if (!vc_sym_req->encrypt)
-		scatterwalk_map_and_copy(req->info, req->src,
-					 req->nbytes - AES_BLOCK_SIZE,
+		scatterwalk_map_and_copy(req->iv, req->src,
+					 req->cryptlen - AES_BLOCK_SIZE,
 					 AES_BLOCK_SIZE, 0);
 
 	sg_init_one(&iv_sg, iv, ivsize);
···
 	return err;
 }
 
-static int virtio_crypto_ablkcipher_encrypt(struct ablkcipher_request *req)
+static int virtio_crypto_skcipher_encrypt(struct skcipher_request *req)
 {
-	struct crypto_ablkcipher *atfm = crypto_ablkcipher_reqtfm(req);
-	struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(atfm);
+	struct crypto_skcipher *atfm = crypto_skcipher_reqtfm(req);
+	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(atfm);
 	struct virtio_crypto_sym_request *vc_sym_req =
-				ablkcipher_request_ctx(req);
+				skcipher_request_ctx(req);
 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 	struct virtio_crypto *vcrypto = ctx->vcrypto;
 	/* Use the first data virtqueue as default */
 	struct data_queue *data_vq = &vcrypto->data_vq[0];
 
-	if (!req->nbytes)
+	if (!req->cryptlen)
 		return 0;
-	if (req->nbytes % AES_BLOCK_SIZE)
+	if (req->cryptlen % AES_BLOCK_SIZE)
 		return -EINVAL;
 
 	vc_req->dataq = data_vq;
 	vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
-	vc_sym_req->ablkcipher_ctx = ctx;
-	vc_sym_req->ablkcipher_req = req;
+	vc_sym_req->skcipher_ctx = ctx;
+	vc_sym_req->skcipher_req = req;
 	vc_sym_req->encrypt = true;
 
-	return crypto_transfer_ablkcipher_request_to_engine(data_vq->engine, req);
+	return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
 }
 
-static int virtio_crypto_ablkcipher_decrypt(struct ablkcipher_request *req)
+static int virtio_crypto_skcipher_decrypt(struct skcipher_request *req)
 {
-	struct crypto_ablkcipher *atfm = crypto_ablkcipher_reqtfm(req);
-	struct virtio_crypto_ablkcipher_ctx *ctx = crypto_ablkcipher_ctx(atfm);
+	struct crypto_skcipher *atfm = crypto_skcipher_reqtfm(req);
+	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(atfm);
 	struct virtio_crypto_sym_request *vc_sym_req =
-				ablkcipher_request_ctx(req);
+				skcipher_request_ctx(req);
 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 	struct virtio_crypto *vcrypto = ctx->vcrypto;
 	/* Use the first data virtqueue as default */
 	struct data_queue *data_vq = &vcrypto->data_vq[0];
 
-	if (!req->nbytes)
+	if (!req->cryptlen)
 		return 0;
-	if (req->nbytes % AES_BLOCK_SIZE)
+	if (req->cryptlen % AES_BLOCK_SIZE)
 		return -EINVAL;
 
 	vc_req->dataq = data_vq;
 	vc_req->alg_cb = virtio_crypto_dataq_sym_callback;
-	vc_sym_req->ablkcipher_ctx = ctx;
-	vc_sym_req->ablkcipher_req = req;
+	vc_sym_req->skcipher_ctx = ctx;
+	vc_sym_req->skcipher_req = req;
 	vc_sym_req->encrypt = false;
 
-	return crypto_transfer_ablkcipher_request_to_engine(data_vq->engine, req);
+	return crypto_transfer_skcipher_request_to_engine(data_vq->engine, req);
 }
 
-static int virtio_crypto_ablkcipher_init(struct crypto_tfm *tfm)
+static int virtio_crypto_skcipher_init(struct crypto_skcipher *tfm)
 {
-	struct virtio_crypto_ablkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
+	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 
-	tfm->crt_ablkcipher.reqsize = sizeof(struct virtio_crypto_sym_request);
+	crypto_skcipher_set_reqsize(tfm, sizeof(struct virtio_crypto_sym_request));
 	ctx->tfm = tfm;
 
-	ctx->enginectx.op.do_one_request = virtio_crypto_ablkcipher_crypt_req;
+	ctx->enginectx.op.do_one_request = virtio_crypto_skcipher_crypt_req;
 	ctx->enginectx.op.prepare_request = NULL;
 	ctx->enginectx.op.unprepare_request = NULL;
 	return 0;
 }
 
-static void virtio_crypto_ablkcipher_exit(struct crypto_tfm *tfm)
+static void virtio_crypto_skcipher_exit(struct crypto_skcipher *tfm)
 {
-	struct virtio_crypto_ablkcipher_ctx *ctx = crypto_tfm_ctx(tfm);
+	struct virtio_crypto_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
 
 	if (!ctx->vcrypto)
 		return;
 
-	virtio_crypto_alg_ablkcipher_close_session(ctx, 1);
-	virtio_crypto_alg_ablkcipher_close_session(ctx, 0);
+	virtio_crypto_alg_skcipher_close_session(ctx, 1);
+	virtio_crypto_alg_skcipher_close_session(ctx, 0);
 	virtcrypto_dev_put(ctx->vcrypto);
 	ctx->vcrypto = NULL;
 }
 
-int virtio_crypto_ablkcipher_crypt_req(
+int virtio_crypto_skcipher_crypt_req(
 	struct crypto_engine *engine, void *vreq)
 {
-	struct ablkcipher_request *req = container_of(vreq, struct ablkcipher_request, base);
+	struct skcipher_request *req = container_of(vreq, struct skcipher_request, base);
 	struct virtio_crypto_sym_request *vc_sym_req =
-				ablkcipher_request_ctx(req);
+				skcipher_request_ctx(req);
 	struct virtio_crypto_request *vc_req = &vc_sym_req->base;
 	struct data_queue *data_vq = vc_req->dataq;
 	int ret;
 
-	ret = __virtio_crypto_ablkcipher_do_req(vc_sym_req, req, data_vq);
+	ret = __virtio_crypto_skcipher_do_req(vc_sym_req, req, data_vq);
 	if (ret < 0)
 		return ret;
 
···
 	return 0;
 }
 
-static void virtio_crypto_ablkcipher_finalize_req(
+static void virtio_crypto_skcipher_finalize_req(
 	struct virtio_crypto_sym_request *vc_sym_req,
-	struct ablkcipher_request *req,
+	struct skcipher_request *req,
 	int err)
 {
 	if (vc_sym_req->encrypt)
-		scatterwalk_map_and_copy(req->info, req->dst,
-					 req->nbytes - AES_BLOCK_SIZE,
+		scatterwalk_map_and_copy(req->iv, req->dst,
+					 req->cryptlen - AES_BLOCK_SIZE,
 					 AES_BLOCK_SIZE, 0);
-	crypto_finalize_ablkcipher_request(vc_sym_req->base.dataq->engine,
+	crypto_finalize_skcipher_request(vc_sym_req->base.dataq->engine,
 					   req, err);
 	kzfree(vc_sym_req->iv);
 	virtcrypto_clear_request(&vc_sym_req->base);
···
 	.algonum = VIRTIO_CRYPTO_CIPHER_AES_CBC,
 	.service = VIRTIO_CRYPTO_SERVICE_CIPHER,
 	.algo = {
-		.cra_name = "cbc(aes)",
-		.cra_driver_name = "virtio_crypto_aes_cbc",
-		.cra_priority = 150,
-		.cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
-		.cra_blocksize = AES_BLOCK_SIZE,
-		.cra_ctxsize  = sizeof(struct virtio_crypto_ablkcipher_ctx),
-		.cra_alignmask = 0,
-		.cra_module = THIS_MODULE,
-		.cra_type = &crypto_ablkcipher_type,
-		.cra_init = virtio_crypto_ablkcipher_init,
-		.cra_exit = virtio_crypto_ablkcipher_exit,
-		.cra_u = {
-			.ablkcipher = {
-				.setkey = virtio_crypto_ablkcipher_setkey,
-				.decrypt = virtio_crypto_ablkcipher_decrypt,
-				.encrypt = virtio_crypto_ablkcipher_encrypt,
-				.min_keysize = AES_MIN_KEY_SIZE,
-				.max_keysize = AES_MAX_KEY_SIZE,
-				.ivsize = AES_BLOCK_SIZE,
-			},
-		},
+		.base.cra_name		= "cbc(aes)",
+		.base.cra_driver_name	= "virtio_crypto_aes_cbc",
+		.base.cra_priority	= 150,
+		.base.cra_flags		= CRYPTO_ALG_ASYNC,
+		.base.cra_blocksize	= AES_BLOCK_SIZE,
+		.base.cra_ctxsize	= sizeof(struct virtio_crypto_skcipher_ctx),
+		.base.cra_module	= THIS_MODULE,
+		.init			= virtio_crypto_skcipher_init,
+		.exit			= virtio_crypto_skcipher_exit,
+		.setkey			= virtio_crypto_skcipher_setkey,
+		.decrypt		= virtio_crypto_skcipher_decrypt,
+		.encrypt		= virtio_crypto_skcipher_encrypt,
+		.min_keysize		= AES_MIN_KEY_SIZE,
+		.max_keysize		= AES_MAX_KEY_SIZE,
+		.ivsize			= AES_BLOCK_SIZE,
 	},
 } };
 
···
 			continue;
 
 		if (virtio_crypto_algs[i].active_devs == 0) {
-			ret = crypto_register_alg(&virtio_crypto_algs[i].algo);
+			ret = crypto_register_skcipher(&virtio_crypto_algs[i].algo);
 			if (ret)
 				goto unlock;
 		}
 
 		virtio_crypto_algs[i].active_devs++;
 		dev_info(&vcrypto->vdev->dev, "Registered algo %s\n",
-			 virtio_crypto_algs[i].algo.cra_name);
+			 virtio_crypto_algs[i].algo.base.cra_name);
 	}
 
 unlock:
···
 			continue;
 
 		if (virtio_crypto_algs[i].active_devs == 1)
-			crypto_unregister_alg(&virtio_crypto_algs[i].algo);
+			crypto_unregister_skcipher(&virtio_crypto_algs[i].algo);
 
 		virtio_crypto_algs[i].active_devs--;
 	}

drivers/crypto/virtio/virtio_crypto_common.h

···
 					      uint32_t algo);
 int virtcrypto_dev_start(struct virtio_crypto *vcrypto);
 void virtcrypto_dev_stop(struct virtio_crypto *vcrypto);
-int virtio_crypto_ablkcipher_crypt_req(
+int virtio_crypto_skcipher_crypt_req(
 	struct crypto_engine *engine, void *vreq);
 
 void