1 files changed, 95 insertions, 0 deletions

diff --git a/crypto/akcipher.c b/crypto/akcipher.c
index 7960ceb528c3..2d10b58c4010 100644
--- a/crypto/akcipher.c
+++ b/crypto/akcipher.c
@@ -10,6 +10,7 @@
 #include <linux/errno.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/scatterlist.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/string.h>
@@ -17,6 +18,19 @@
 
 #include "internal.h"
 
+struct crypto_akcipher_sync_data {
+	struct crypto_akcipher *tfm;
+	const void *src;
+	void *dst;
+	unsigned int slen;
+	unsigned int dlen;
+
+	struct akcipher_request *req;
+	struct crypto_wait cwait;
+	struct scatterlist sg;
+	u8 *buf;
+};
+
 static int __maybe_unused crypto_akcipher_report(
 	struct sk_buff *skb, struct crypto_alg *alg)
 {
@@ -186,5 +200,86 @@ int akcipher_register_instance(struct crypto_template *tmpl,
 }
 EXPORT_SYMBOL_GPL(akcipher_register_instance);
 
+static int crypto_akcipher_sync_prep(struct crypto_akcipher_sync_data *data)
+{
+	unsigned int reqsize = crypto_akcipher_reqsize(data->tfm);
+	unsigned int mlen = max(data->slen, data->dlen);
+	struct akcipher_request *req;
+	struct scatterlist *sg;
+	unsigned int len;
+	u8 *buf;
+
+	len = sizeof(*req) + reqsize + mlen;
+	if (len < mlen)
+		return -EOVERFLOW;
+
+	req = kzalloc(len, GFP_KERNEL);
+	if (!req)
+		return -ENOMEM;
+
+	data->req = req;
+
+	buf = (u8 *)(req + 1) + reqsize;
+	data->buf = buf;
+	memcpy(buf, data->src, data->slen);
+
+	sg = &data->sg;
+	sg_init_one(sg, buf, mlen);
+	akcipher_request_set_crypt(req, sg, sg, data->slen, data->dlen);
+
+	crypto_init_wait(&data->cwait);
+	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP,
+				      crypto_req_done, &data->cwait);
+
+	return 0;
+}
+
+static int crypto_akcipher_sync_post(struct crypto_akcipher_sync_data *data,
+				     int err)
+{
+	err = crypto_wait_req(err, &data->cwait);
+	memcpy(data->dst, data->buf, data->dlen);
+	data->dlen = data->req->dst_len;
+	kfree_sensitive(data->req);
+	return err;
+}
+
+int crypto_akcipher_sync_encrypt(struct crypto_akcipher *tfm,
+				 const void *src, unsigned int slen,
+				 void *dst, unsigned int dlen)
+{
+	struct crypto_akcipher_sync_data data = {
+		.tfm = tfm,
+		.src = src,
+		.dst = dst,
+		.slen = slen,
+		.dlen = dlen,
+	};
+
+	return crypto_akcipher_sync_prep(&data) ?:
+	       crypto_akcipher_sync_post(&data,
+					 crypto_akcipher_encrypt(data.req));
+}
+EXPORT_SYMBOL_GPL(crypto_akcipher_sync_encrypt);
+
+int crypto_akcipher_sync_decrypt(struct crypto_akcipher *tfm,
+				 const void *src, unsigned int slen,
+				 void *dst, unsigned int dlen)
+{
+	struct crypto_akcipher_sync_data data = {
+		.tfm = tfm,
+		.src = src,
+		.dst = dst,
+		.slen = slen,
+		.dlen = dlen,
+	};
+
+	return crypto_akcipher_sync_prep(&data) ?:
+	       crypto_akcipher_sync_post(&data,
+					 crypto_akcipher_decrypt(data.req)) ?:
+	       data.dlen;
+}
+EXPORT_SYMBOL_GPL(crypto_akcipher_sync_decrypt);
+
 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("Generic public key cipher type");