+ struct crypto_aead *authenc = crypto_aead_reqtfm(req);
+ u8 *ohash;
+ u8 *ihash;
+ unsigned int authsize;
+
+ ohash = crypto_authenc_hash(req, CRYPTO_TFM_REQ_MAY_SLEEP, cipher,
+ cryptlen);
+ if (IS_ERR(ohash))
+ return PTR_ERR(ohash);
+
+ authsize = crypto_aead_authsize(authenc);
+ ihash = ohash + authsize;
+ scatterwalk_map_and_copy(ihash, cipher, cryptlen, authsize, 0);
+ return memcmp(ihash, ohash, authsize) ? -EBADMSG: 0;
+}
+
+static int crypto_authenc_iverify(struct aead_request *req, u8 *iv,
+ unsigned int cryptlen)
+{
+ struct crypto_aead *authenc = crypto_aead_reqtfm(req);
+ struct scatterlist *src = req->src;
+ struct scatterlist cipher[2];
+ struct page *srcp;
+ unsigned int ivsize = crypto_aead_ivsize(authenc);
+ u8 *vsrc;
+
+ srcp = sg_page(src);
+ vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
+
+ sg_init_table(cipher, 2);
+ sg_set_buf(cipher, iv, ivsize);
+ authenc_chain(cipher, src, vsrc == iv + ivsize);
+
+ return crypto_authenc_verify(req, cipher, cryptlen + ivsize);