File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/crypto/authencesn.c b/crypto/authencesn.c
new file mode 100644
index 0000000..52154ef
--- /dev/null
+++ b/crypto/authencesn.c
@@ -0,0 +1,525 @@
+/*
+ * authencesn.c - AEAD wrapper for IPsec with extended sequence numbers,
+ *                 derived from authenc.c
+ *
+ * Copyright (C) 2010 secunet Security Networks AG
+ * Copyright (C) 2010 Steffen Klassert <steffen.klassert@secunet.com>
+ * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#include <crypto/internal/aead.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/authenc.h>
+#include <crypto/null.h>
+#include <crypto/scatterwalk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rtnetlink.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+struct authenc_esn_instance_ctx {
+	struct crypto_ahash_spawn auth;
+	struct crypto_skcipher_spawn enc;
+};
+
+struct crypto_authenc_esn_ctx {
+	unsigned int reqoff;
+	struct crypto_ahash *auth;
+	struct crypto_ablkcipher *enc;
+	struct crypto_blkcipher *null;
+};
+
+struct authenc_esn_request_ctx {
+	struct scatterlist src[2];
+	struct scatterlist dst[2];
+	char tail[];
+};
+
+static void authenc_esn_request_complete(struct aead_request *req, int err)
+{
+	if (err != -EINPROGRESS)
+		aead_request_complete(req, err);
+}
+
+static int crypto_authenc_esn_setauthsize(struct crypto_aead *authenc_esn,
+					  unsigned int authsize)
+{
+	if (authsize > 0 && authsize < 4)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int crypto_authenc_esn_setkey(struct crypto_aead *authenc_esn, const u8 *key,
+				     unsigned int keylen)
+{
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct crypto_ahash *auth = ctx->auth;
+	struct crypto_ablkcipher *enc = ctx->enc;
+	struct crypto_authenc_keys keys;
+	int err = -EINVAL;
+
+	if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
+		goto badkey;
+
+	crypto_ahash_clear_flags(auth, CRYPTO_TFM_REQ_MASK);
+	crypto_ahash_set_flags(auth, crypto_aead_get_flags(authenc_esn) &
+				     CRYPTO_TFM_REQ_MASK);
+	err = crypto_ahash_setkey(auth, keys.authkey, keys.authkeylen);
+	crypto_aead_set_flags(authenc_esn, crypto_ahash_get_flags(auth) &
+					   CRYPTO_TFM_RES_MASK);
+
+	if (err)
+		goto out;
+
+	crypto_ablkcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
+	crypto_ablkcipher_set_flags(enc, crypto_aead_get_flags(authenc_esn) &
+					 CRYPTO_TFM_REQ_MASK);
+	err = crypto_ablkcipher_setkey(enc, keys.enckey, keys.enckeylen);
+	crypto_aead_set_flags(authenc_esn, crypto_ablkcipher_get_flags(enc) &
+					   CRYPTO_TFM_RES_MASK);
+
+out:
+	return err;
+
+badkey:
+	crypto_aead_set_flags(authenc_esn, CRYPTO_TFM_RES_BAD_KEY_LEN);
+	goto out;
+}
+
+static int crypto_authenc_esn_genicv_tail(struct aead_request *req,
+					  unsigned int flags)
+{
+	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct crypto_ahash *auth = ctx->auth;
+	u8 *hash = PTR_ALIGN((u8 *)areq_ctx->tail,
+			     crypto_ahash_alignmask(auth) + 1);
+	unsigned int authsize = crypto_aead_authsize(authenc_esn);
+	unsigned int assoclen = req->assoclen;
+	unsigned int cryptlen = req->cryptlen;
+	struct scatterlist *dst = req->dst;
+	u32 tmp[2];
+
+	/* Move high-order bits of sequence number back. */
+	scatterwalk_map_and_copy(tmp, dst, 4, 4, 0);
+	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0);
+	scatterwalk_map_and_copy(tmp, dst, 0, 8, 1);
+
+	scatterwalk_map_and_copy(hash, dst, assoclen + cryptlen, authsize, 1);
+	return 0;
+}
+
+static void authenc_esn_geniv_ahash_done(struct crypto_async_request *areq,
+					 int err)
+{
+	struct aead_request *req = areq->data;
+
+	err = err ?: crypto_authenc_esn_genicv_tail(req, 0);
+	aead_request_complete(req, err);
+}
+
+static int crypto_authenc_esn_genicv(struct aead_request *req,
+				     unsigned int flags)
+{
+	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
+	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct crypto_ahash *auth = ctx->auth;
+	u8 *hash = PTR_ALIGN((u8 *)areq_ctx->tail,
+			     crypto_ahash_alignmask(auth) + 1);
+	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
+	unsigned int authsize = crypto_aead_authsize(authenc_esn);
+	unsigned int assoclen = req->assoclen;
+	unsigned int cryptlen = req->cryptlen;
+	struct scatterlist *dst = req->dst;
+	u32 tmp[2];
+
+	if (!authsize)
+		return 0;
+
+	/* Move high-order bits of sequence number to the end. */
+	scatterwalk_map_and_copy(tmp, dst, 0, 8, 0);
+	scatterwalk_map_and_copy(tmp, dst, 4, 4, 1);
+	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1);
+
+	sg_init_table(areq_ctx->dst, 2);
+	dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4);
+
+	ahash_request_set_tfm(ahreq, auth);
+	ahash_request_set_crypt(ahreq, dst, hash, assoclen + cryptlen);
+	ahash_request_set_callback(ahreq, flags,
+				   authenc_esn_geniv_ahash_done, req);
+
+	return crypto_ahash_digest(ahreq) ?:
+	       crypto_authenc_esn_genicv_tail(req, aead_request_flags(req));
+}
+
+
+static void crypto_authenc_esn_encrypt_done(struct crypto_async_request *req,
+					    int err)
+{
+	struct aead_request *areq = req->data;
+
+	if (!err)
+		err = crypto_authenc_esn_genicv(areq, 0);
+
+	authenc_esn_request_complete(areq, err);
+}
+
+static int crypto_authenc_esn_copy(struct aead_request *req, unsigned int len)
+{
+	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct blkcipher_desc desc = {
+		.tfm = ctx->null,
+	};
+
+	return crypto_blkcipher_encrypt(&desc, req->dst, req->src, len);
+}
+
+static int crypto_authenc_esn_encrypt(struct aead_request *req)
+{
+	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
+	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
+						    + ctx->reqoff);
+	struct crypto_ablkcipher *enc = ctx->enc;
+	unsigned int assoclen = req->assoclen;
+	unsigned int cryptlen = req->cryptlen;
+	struct scatterlist *src, *dst;
+	int err;
+
+	sg_init_table(areq_ctx->src, 2);
+	src = scatterwalk_ffwd(areq_ctx->src, req->src, assoclen);
+	dst = src;
+
+	if (req->src != req->dst) {
+		err = crypto_authenc_esn_copy(req, assoclen);
+		if (err)
+			return err;
+
+		sg_init_table(areq_ctx->dst, 2);
+		dst = scatterwalk_ffwd(areq_ctx->dst, req->dst, assoclen);
+	}
+
+	ablkcipher_request_set_tfm(abreq, enc);
+	ablkcipher_request_set_callback(abreq, aead_request_flags(req),
+					crypto_authenc_esn_encrypt_done, req);
+	ablkcipher_request_set_crypt(abreq, src, dst, cryptlen, req->iv);
+
+	err = crypto_ablkcipher_encrypt(abreq);
+	if (err)
+		return err;
+
+	return crypto_authenc_esn_genicv(req, aead_request_flags(req));
+}
+
+static int crypto_authenc_esn_decrypt_tail(struct aead_request *req,
+					   unsigned int flags)
+{
+	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
+	unsigned int authsize = crypto_aead_authsize(authenc_esn);
+	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct ablkcipher_request *abreq = (void *)(areq_ctx->tail
+						    + ctx->reqoff);
+	struct crypto_ahash *auth = ctx->auth;
+	u8 *ohash = PTR_ALIGN((u8 *)areq_ctx->tail,
+			      crypto_ahash_alignmask(auth) + 1);
+	unsigned int cryptlen = req->cryptlen - authsize;
+	unsigned int assoclen = req->assoclen;
+	struct scatterlist *dst = req->dst;
+	u8 *ihash = ohash + crypto_ahash_digestsize(auth);
+	u32 tmp[2];
+
+	if (!authsize)
+		goto decrypt;
+
+	/* Move high-order bits of sequence number back. */
+	scatterwalk_map_and_copy(tmp, dst, 4, 4, 0);
+	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0);
+	scatterwalk_map_and_copy(tmp, dst, 0, 8, 1);
+
+	if (crypto_memneq(ihash, ohash, authsize))
+		return -EBADMSG;
+
+decrypt:
+
+	sg_init_table(areq_ctx->dst, 2);
+	dst = scatterwalk_ffwd(areq_ctx->dst, dst, assoclen);
+
+	ablkcipher_request_set_tfm(abreq, ctx->enc);
+	ablkcipher_request_set_callback(abreq, flags,
+					req->base.complete, req->base.data);
+	ablkcipher_request_set_crypt(abreq, dst, dst, cryptlen, req->iv);
+
+	return crypto_ablkcipher_decrypt(abreq);
+}
+
+static void authenc_esn_verify_ahash_done(struct crypto_async_request *areq,
+					  int err)
+{
+	struct aead_request *req = areq->data;
+
+	err = err ?: crypto_authenc_esn_decrypt_tail(req, 0);
+	aead_request_complete(req, err);
+}
+
+static int crypto_authenc_esn_decrypt(struct aead_request *req)
+{
+	struct crypto_aead *authenc_esn = crypto_aead_reqtfm(req);
+	struct authenc_esn_request_ctx *areq_ctx = aead_request_ctx(req);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(authenc_esn);
+	struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
+	unsigned int authsize = crypto_aead_authsize(authenc_esn);
+	struct crypto_ahash *auth = ctx->auth;
+	u8 *ohash = PTR_ALIGN((u8 *)areq_ctx->tail,
+			      crypto_ahash_alignmask(auth) + 1);
+	unsigned int assoclen = req->assoclen;
+	unsigned int cryptlen = req->cryptlen;
+	u8 *ihash = ohash + crypto_ahash_digestsize(auth);
+	struct scatterlist *dst = req->dst;
+	u32 tmp[2];
+	int err;
+
+	cryptlen -= authsize;
+
+	if (req->src != dst) {
+		err = crypto_authenc_esn_copy(req, assoclen + cryptlen);
+		if (err)
+			return err;
+	}
+
+	scatterwalk_map_and_copy(ihash, req->src, assoclen + cryptlen,
+				 authsize, 0);
+
+	if (!authsize)
+		goto tail;
+
+	/* Move high-order bits of sequence number to the end. */
+	scatterwalk_map_and_copy(tmp, dst, 0, 8, 0);
+	scatterwalk_map_and_copy(tmp, dst, 4, 4, 1);
+	scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1);
+
+	sg_init_table(areq_ctx->dst, 2);
+	dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4);
+
+	ahash_request_set_tfm(ahreq, auth);
+	ahash_request_set_crypt(ahreq, dst, ohash, assoclen + cryptlen);
+	ahash_request_set_callback(ahreq, aead_request_flags(req),
+				   authenc_esn_verify_ahash_done, req);
+
+	err = crypto_ahash_digest(ahreq);
+	if (err)
+		return err;
+
+tail:
+	return crypto_authenc_esn_decrypt_tail(req, aead_request_flags(req));
+}
+
+static int crypto_authenc_esn_init_tfm(struct crypto_aead *tfm)
+{
+	struct aead_instance *inst = aead_alg_instance(tfm);
+	struct authenc_esn_instance_ctx *ictx = aead_instance_ctx(inst);
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(tfm);
+	struct crypto_ahash *auth;
+	struct crypto_ablkcipher *enc;
+	struct crypto_blkcipher *null;
+	int err;
+
+	auth = crypto_spawn_ahash(&ictx->auth);
+	if (IS_ERR(auth))
+		return PTR_ERR(auth);
+
+	enc = crypto_spawn_skcipher(&ictx->enc);
+	err = PTR_ERR(enc);
+	if (IS_ERR(enc))
+		goto err_free_ahash;
+
+	null = crypto_get_default_null_skcipher();
+	err = PTR_ERR(null);
+	if (IS_ERR(null))
+		goto err_free_skcipher;
+
+	ctx->auth = auth;
+	ctx->enc = enc;
+	ctx->null = null;
+
+	ctx->reqoff = ALIGN(2 * crypto_ahash_digestsize(auth),
+			    crypto_ahash_alignmask(auth) + 1);
+
+	crypto_aead_set_reqsize(
+		tfm,
+		sizeof(struct authenc_esn_request_ctx) +
+		ctx->reqoff +
+		max_t(unsigned int,
+			crypto_ahash_reqsize(auth) +
+			sizeof(struct ahash_request),
+			sizeof(struct skcipher_givcrypt_request) +
+			crypto_ablkcipher_reqsize(enc)));
+
+	return 0;
+
+err_free_skcipher:
+	crypto_free_ablkcipher(enc);
+err_free_ahash:
+	crypto_free_ahash(auth);
+	return err;
+}
+
+static void crypto_authenc_esn_exit_tfm(struct crypto_aead *tfm)
+{
+	struct crypto_authenc_esn_ctx *ctx = crypto_aead_ctx(tfm);
+
+	crypto_free_ahash(ctx->auth);
+	crypto_free_ablkcipher(ctx->enc);
+	crypto_put_default_null_skcipher();
+}
+
+static void crypto_authenc_esn_free(struct aead_instance *inst)
+{
+	struct authenc_esn_instance_ctx *ctx = aead_instance_ctx(inst);
+
+	crypto_drop_skcipher(&ctx->enc);
+	crypto_drop_ahash(&ctx->auth);
+	kfree(inst);
+}
+
+static int crypto_authenc_esn_create(struct crypto_template *tmpl,
+				     struct rtattr **tb)
+{
+	struct crypto_attr_type *algt;
+	struct aead_instance *inst;
+	struct hash_alg_common *auth;
+	struct crypto_alg *auth_base;
+	struct crypto_alg *enc;
+	struct authenc_esn_instance_ctx *ctx;
+	const char *enc_name;
+	int err;
+
+	algt = crypto_get_attr_type(tb);
+	if (IS_ERR(algt))
+		return PTR_ERR(algt);
+
+	if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
+		return -EINVAL;
+
+	auth = ahash_attr_alg(tb[1], CRYPTO_ALG_TYPE_HASH,
+			       CRYPTO_ALG_TYPE_AHASH_MASK);
+	if (IS_ERR(auth))
+		return PTR_ERR(auth);
+
+	auth_base = &auth->base;
+
+	enc_name = crypto_attr_alg_name(tb[2]);
+	err = PTR_ERR(enc_name);
+	if (IS_ERR(enc_name))
+		goto out_put_auth;
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
+	err = -ENOMEM;
+	if (!inst)
+		goto out_put_auth;
+
+	ctx = aead_instance_ctx(inst);
+
+	err = crypto_init_ahash_spawn(&ctx->auth, auth,
+				      aead_crypto_instance(inst));
+	if (err)
+		goto err_free_inst;
+
+	crypto_set_skcipher_spawn(&ctx->enc, aead_crypto_instance(inst));
+	err = crypto_grab_skcipher(&ctx->enc, enc_name, 0,
+				   crypto_requires_sync(algt->type,
+							algt->mask));
+	if (err)
+		goto err_drop_auth;
+
+	enc = crypto_skcipher_spawn_alg(&ctx->enc);
+
+	err = -ENAMETOOLONG;
+	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+		     "authencesn(%s,%s)", auth_base->cra_name,
+		     enc->cra_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_drop_enc;
+
+	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+		     "authencesn(%s,%s)", auth_base->cra_driver_name,
+		     enc->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_drop_enc;
+
+	inst->alg.base.cra_flags = enc->cra_flags & CRYPTO_ALG_ASYNC;
+	inst->alg.base.cra_priority = enc->cra_priority * 10 +
+				      auth_base->cra_priority;
+	inst->alg.base.cra_blocksize = enc->cra_blocksize;
+	inst->alg.base.cra_alignmask = auth_base->cra_alignmask |
+				       enc->cra_alignmask;
+	inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_esn_ctx);
+
+	inst->alg.ivsize = enc->cra_ablkcipher.ivsize;
+	inst->alg.maxauthsize = auth->digestsize;
+
+	inst->alg.init = crypto_authenc_esn_init_tfm;
+	inst->alg.exit = crypto_authenc_esn_exit_tfm;
+
+	inst->alg.setkey = crypto_authenc_esn_setkey;
+	inst->alg.setauthsize = crypto_authenc_esn_setauthsize;
+	inst->alg.encrypt = crypto_authenc_esn_encrypt;
+	inst->alg.decrypt = crypto_authenc_esn_decrypt;
+
+	inst->free = crypto_authenc_esn_free,
+
+	err = aead_register_instance(tmpl, inst);
+	if (err)
+		goto err_drop_enc;
+
+out:
+	crypto_mod_put(auth_base);
+	return err;
+
+err_drop_enc:
+	crypto_drop_skcipher(&ctx->enc);
+err_drop_auth:
+	crypto_drop_ahash(&ctx->auth);
+err_free_inst:
+	kfree(inst);
+out_put_auth:
+	goto out;
+}
+
+static struct crypto_template crypto_authenc_esn_tmpl = {
+	.name = "authencesn",
+	.create = crypto_authenc_esn_create,
+	.module = THIS_MODULE,
+};
+
+static int __init crypto_authenc_esn_module_init(void)
+{
+	return crypto_register_template(&crypto_authenc_esn_tmpl);
+}
+
+static void __exit crypto_authenc_esn_module_exit(void)
+{
+	crypto_unregister_template(&crypto_authenc_esn_tmpl);
+}
+
+module_init(crypto_authenc_esn_module_init);
+module_exit(crypto_authenc_esn_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
+MODULE_DESCRIPTION("AEAD wrapper for IPsec with extended sequence numbers");
+MODULE_ALIAS_CRYPTO("authencesn");