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-rw-r--r--crypto/authencesn.c485
1 files changed, 485 insertions, 0 deletions
diff --git a/crypto/authencesn.c b/crypto/authencesn.c
new file mode 100644
index 000000000..b60e61b19
--- /dev/null
+++ b/crypto/authencesn.c
@@ -0,0 +1,485 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+
+#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_skcipher *enc;
+ struct crypto_sync_skcipher *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_skcipher *enc = ctx->enc;
+ struct crypto_authenc_keys keys;
+ int err = -EINVAL;
+
+ if (crypto_authenc_extractkeys(&keys, key, keylen) != 0)
+ goto out;
+
+ 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);
+ if (err)
+ goto out;
+
+ crypto_skcipher_clear_flags(enc, CRYPTO_TFM_REQ_MASK);
+ crypto_skcipher_set_flags(enc, crypto_aead_get_flags(authenc_esn) &
+ CRYPTO_TFM_REQ_MASK);
+ err = crypto_skcipher_setkey(enc, keys.enckey, keys.enckeylen);
+out:
+ memzero_explicit(&keys, sizeof(keys));
+ return err;
+}
+
+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);
+ SYNC_SKCIPHER_REQUEST_ON_STACK(skreq, ctx->null);
+
+ skcipher_request_set_sync_tfm(skreq, ctx->null);
+ skcipher_request_set_callback(skreq, aead_request_flags(req),
+ NULL, NULL);
+ skcipher_request_set_crypt(skreq, req->src, req->dst, len, NULL);
+
+ return crypto_skcipher_encrypt(skreq);
+}
+
+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 skcipher_request *skreq = (void *)(areq_ctx->tail +
+ ctx->reqoff);
+ struct crypto_skcipher *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);
+ }
+
+ skcipher_request_set_tfm(skreq, enc);
+ skcipher_request_set_callback(skreq, aead_request_flags(req),
+ crypto_authenc_esn_encrypt_done, req);
+ skcipher_request_set_crypt(skreq, src, dst, cryptlen, req->iv);
+
+ err = crypto_skcipher_encrypt(skreq);
+ 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 skcipher_request *skreq = (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);
+
+ skcipher_request_set_tfm(skreq, ctx->enc);
+ skcipher_request_set_callback(skreq, flags,
+ req->base.complete, req->base.data);
+ skcipher_request_set_crypt(skreq, dst, dst, cryptlen, req->iv);
+
+ return crypto_skcipher_decrypt(skreq);
+}
+
+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);
+ authenc_esn_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_skcipher *enc;
+ struct crypto_sync_skcipher *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_request) +
+ crypto_skcipher_reqsize(enc)));
+
+ return 0;
+
+err_free_skcipher:
+ crypto_free_skcipher(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_skcipher(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)
+{
+ u32 mask;
+ struct aead_instance *inst;
+ struct authenc_esn_instance_ctx *ctx;
+ struct hash_alg_common *auth;
+ struct crypto_alg *auth_base;
+ struct skcipher_alg *enc;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD, &mask);
+ if (err)
+ return err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
+ if (!inst)
+ return -ENOMEM;
+ ctx = aead_instance_ctx(inst);
+
+ err = crypto_grab_ahash(&ctx->auth, aead_crypto_instance(inst),
+ crypto_attr_alg_name(tb[1]), 0, mask);
+ if (err)
+ goto err_free_inst;
+ auth = crypto_spawn_ahash_alg(&ctx->auth);
+ auth_base = &auth->base;
+
+ err = crypto_grab_skcipher(&ctx->enc, aead_crypto_instance(inst),
+ crypto_attr_alg_name(tb[2]), 0, mask);
+ if (err)
+ goto err_free_inst;
+ enc = crypto_spawn_skcipher_alg(&ctx->enc);
+
+ err = -ENAMETOOLONG;
+ if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+ "authencesn(%s,%s)", auth_base->cra_name,
+ enc->base.cra_name) >= CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+ "authencesn(%s,%s)", auth_base->cra_driver_name,
+ enc->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = enc->base.cra_priority * 10 +
+ auth_base->cra_priority;
+ inst->alg.base.cra_blocksize = enc->base.cra_blocksize;
+ inst->alg.base.cra_alignmask = auth_base->cra_alignmask |
+ enc->base.cra_alignmask;
+ inst->alg.base.cra_ctxsize = sizeof(struct crypto_authenc_esn_ctx);
+
+ inst->alg.ivsize = crypto_skcipher_alg_ivsize(enc);
+ inst->alg.chunksize = crypto_skcipher_alg_chunksize(enc);
+ 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) {
+err_free_inst:
+ crypto_authenc_esn_free(inst);
+ }
+ return err;
+}
+
+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);
+}
+
+subsys_initcall(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");