crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539
This AEAD uses a chacha20 ablkcipher and a poly1305 ahash to construct the ChaCha20-Poly1305 AEAD as defined in RFC7539. It supports both synchronous and asynchronous operations, even if we currently have no async chacha20 or poly1305 drivers. Signed-off-by: Martin Willi <martin@strongswan.org> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Martin Willi
Herbert Xu
parent
eee9dc6162
commit
71ebc4d1b2
3 changed files with 676 additions and 0 deletions
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@ -217,6 +217,18 @@ config CRYPTO_GCM
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Support for Galois/Counter Mode (GCM) and Galois Message
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Authentication Code (GMAC). Required for IPSec.
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config CRYPTO_CHACHA20POLY1305
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tristate "ChaCha20-Poly1305 AEAD support"
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select CRYPTO_CHACHA20
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select CRYPTO_POLY1305
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select CRYPTO_AEAD
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help
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ChaCha20-Poly1305 AEAD support, RFC7539.
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Support for the AEAD wrapper using the ChaCha20 stream cipher combined
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with the Poly1305 authenticator. It is defined in RFC7539 for use in
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IETF protocols.
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config CRYPTO_SEQIV
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tristate "Sequence Number IV Generator"
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select CRYPTO_AEAD
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@ -59,6 +59,7 @@ obj-$(CONFIG_CRYPTO_XTS) += xts.o
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obj-$(CONFIG_CRYPTO_CTR) += ctr.o
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obj-$(CONFIG_CRYPTO_GCM) += gcm.o
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obj-$(CONFIG_CRYPTO_CCM) += ccm.o
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obj-$(CONFIG_CRYPTO_CHACHA20POLY1305) += chacha20poly1305.o
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obj-$(CONFIG_CRYPTO_PCRYPT) += pcrypt.o
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obj-$(CONFIG_CRYPTO_CRYPTD) += cryptd.o
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obj-$(CONFIG_CRYPTO_MCRYPTD) += mcryptd.o
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663
crypto/chacha20poly1305.c
Normal file
663
crypto/chacha20poly1305.c
Normal file
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@ -0,0 +1,663 @@
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/*
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* ChaCha20-Poly1305 AEAD, RFC7539
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*
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* Copyright (C) 2015 Martin Willi
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*/
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#include <crypto/internal/aead.h>
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#include <crypto/internal/hash.h>
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#include <crypto/internal/skcipher.h>
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#include <crypto/scatterwalk.h>
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#include <linux/err.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include "internal.h"
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#define POLY1305_BLOCK_SIZE 16
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#define POLY1305_DIGEST_SIZE 16
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#define POLY1305_KEY_SIZE 32
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#define CHACHA20_KEY_SIZE 32
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#define CHACHA20_IV_SIZE 16
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#define CHACHAPOLY_IV_SIZE 12
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struct chachapoly_instance_ctx {
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struct crypto_skcipher_spawn chacha;
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struct crypto_ahash_spawn poly;
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unsigned int saltlen;
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};
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struct chachapoly_ctx {
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struct crypto_ablkcipher *chacha;
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struct crypto_ahash *poly;
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/* key bytes we use for the ChaCha20 IV */
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unsigned int saltlen;
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u8 salt[];
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};
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struct poly_req {
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/* zero byte padding for AD/ciphertext, as needed */
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u8 pad[POLY1305_BLOCK_SIZE];
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/* tail data with AD/ciphertext lengths */
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struct {
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__le64 assoclen;
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__le64 cryptlen;
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} tail;
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struct scatterlist src[1];
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struct ahash_request req; /* must be last member */
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};
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struct chacha_req {
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/* the key we generate for Poly1305 using Chacha20 */
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u8 key[POLY1305_KEY_SIZE];
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u8 iv[CHACHA20_IV_SIZE];
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struct scatterlist src[1];
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struct ablkcipher_request req; /* must be last member */
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};
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struct chachapoly_req_ctx {
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/* calculated Poly1305 tag */
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u8 tag[POLY1305_DIGEST_SIZE];
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/* length of data to en/decrypt, without ICV */
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unsigned int cryptlen;
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union {
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struct poly_req poly;
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struct chacha_req chacha;
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} u;
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};
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static inline void async_done_continue(struct aead_request *req, int err,
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int (*cont)(struct aead_request *))
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{
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if (!err)
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err = cont(req);
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if (err != -EINPROGRESS && err != -EBUSY)
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aead_request_complete(req, err);
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}
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static void chacha_iv(u8 *iv, struct aead_request *req, u32 icb)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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__le32 leicb = cpu_to_le32(icb);
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memcpy(iv, &leicb, sizeof(leicb));
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memcpy(iv + sizeof(leicb), ctx->salt, ctx->saltlen);
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memcpy(iv + sizeof(leicb) + ctx->saltlen, req->iv,
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CHACHA20_IV_SIZE - sizeof(leicb) - ctx->saltlen);
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}
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static int poly_verify_tag(struct aead_request *req)
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{
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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u8 tag[sizeof(rctx->tag)];
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scatterwalk_map_and_copy(tag, req->src, rctx->cryptlen, sizeof(tag), 0);
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if (crypto_memneq(tag, rctx->tag, sizeof(tag)))
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return -EBADMSG;
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return 0;
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}
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static int poly_copy_tag(struct aead_request *req)
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{
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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scatterwalk_map_and_copy(rctx->tag, req->dst, rctx->cryptlen,
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sizeof(rctx->tag), 1);
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return 0;
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}
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static void chacha_decrypt_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_verify_tag);
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}
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static int chacha_decrypt(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct chacha_req *creq = &rctx->u.chacha;
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int err;
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chacha_iv(creq->iv, req, 1);
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ablkcipher_request_set_callback(&creq->req, aead_request_flags(req),
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chacha_decrypt_done, req);
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ablkcipher_request_set_tfm(&creq->req, ctx->chacha);
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ablkcipher_request_set_crypt(&creq->req, req->src, req->dst,
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rctx->cryptlen, creq->iv);
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err = crypto_ablkcipher_decrypt(&creq->req);
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if (err)
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return err;
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return poly_verify_tag(req);
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}
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static int poly_tail_continue(struct aead_request *req)
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{
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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if (rctx->cryptlen == req->cryptlen) /* encrypting */
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return poly_copy_tag(req);
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return chacha_decrypt(req);
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}
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static void poly_tail_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_tail_continue);
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}
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static int poly_tail(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct poly_req *preq = &rctx->u.poly;
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__le64 len;
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int err;
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sg_init_table(preq->src, 1);
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len = cpu_to_le64(req->assoclen);
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memcpy(&preq->tail.assoclen, &len, sizeof(len));
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len = cpu_to_le64(rctx->cryptlen);
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memcpy(&preq->tail.cryptlen, &len, sizeof(len));
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sg_set_buf(preq->src, &preq->tail, sizeof(preq->tail));
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_tail_done, req);
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ahash_request_set_tfm(&preq->req, ctx->poly);
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ahash_request_set_crypt(&preq->req, preq->src,
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rctx->tag, sizeof(preq->tail));
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err = crypto_ahash_finup(&preq->req);
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if (err)
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return err;
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return poly_tail_continue(req);
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}
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static void poly_cipherpad_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_tail);
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}
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static int poly_cipherpad(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct poly_req *preq = &rctx->u.poly;
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unsigned int padlen, bs = POLY1305_BLOCK_SIZE;
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int err;
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padlen = (bs - (rctx->cryptlen % bs)) % bs;
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memset(preq->pad, 0, sizeof(preq->pad));
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sg_init_table(preq->src, 1);
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sg_set_buf(preq->src, &preq->pad, padlen);
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_cipherpad_done, req);
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ahash_request_set_tfm(&preq->req, ctx->poly);
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ahash_request_set_crypt(&preq->req, preq->src, NULL, padlen);
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err = crypto_ahash_update(&preq->req);
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if (err)
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return err;
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return poly_tail(req);
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}
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static void poly_cipher_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_cipherpad);
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}
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static int poly_cipher(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct poly_req *preq = &rctx->u.poly;
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struct scatterlist *crypt = req->src;
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int err;
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if (rctx->cryptlen == req->cryptlen) /* encrypting */
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crypt = req->dst;
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_cipher_done, req);
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ahash_request_set_tfm(&preq->req, ctx->poly);
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ahash_request_set_crypt(&preq->req, crypt, NULL, rctx->cryptlen);
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err = crypto_ahash_update(&preq->req);
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if (err)
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return err;
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return poly_cipherpad(req);
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}
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static void poly_adpad_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_cipher);
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}
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static int poly_adpad(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct poly_req *preq = &rctx->u.poly;
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unsigned int padlen, bs = POLY1305_BLOCK_SIZE;
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int err;
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padlen = (bs - (req->assoclen % bs)) % bs;
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memset(preq->pad, 0, sizeof(preq->pad));
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sg_init_table(preq->src, 1);
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sg_set_buf(preq->src, preq->pad, padlen);
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_adpad_done, req);
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ahash_request_set_tfm(&preq->req, ctx->poly);
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ahash_request_set_crypt(&preq->req, preq->src, NULL, padlen);
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err = crypto_ahash_update(&preq->req);
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if (err)
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return err;
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return poly_cipher(req);
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}
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static void poly_ad_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_adpad);
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}
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static int poly_ad(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct poly_req *preq = &rctx->u.poly;
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int err;
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_ad_done, req);
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ahash_request_set_tfm(&preq->req, ctx->poly);
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ahash_request_set_crypt(&preq->req, req->assoc, NULL, req->assoclen);
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err = crypto_ahash_update(&preq->req);
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if (err)
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return err;
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return poly_adpad(req);
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}
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static void poly_init_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_ad);
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}
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static int poly_init(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct poly_req *preq = &rctx->u.poly;
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int err;
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_init_done, req);
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ahash_request_set_tfm(&preq->req, ctx->poly);
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err = crypto_ahash_init(&preq->req);
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if (err)
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return err;
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return poly_ad(req);
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}
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static int poly_genkey_continue(struct aead_request *req)
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{
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struct crypto_aead *aead = crypto_aead_reqtfm(req);
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struct chachapoly_ctx *ctx = crypto_aead_ctx(aead);
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct chacha_req *creq = &rctx->u.chacha;
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int err;
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crypto_ahash_clear_flags(ctx->poly, CRYPTO_TFM_REQ_MASK);
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crypto_ahash_set_flags(ctx->poly, crypto_aead_get_flags(aead) &
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CRYPTO_TFM_REQ_MASK);
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err = crypto_ahash_setkey(ctx->poly, creq->key, sizeof(creq->key));
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crypto_aead_set_flags(aead, crypto_ahash_get_flags(ctx->poly) &
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CRYPTO_TFM_RES_MASK);
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if (err)
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return err;
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return poly_init(req);
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}
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static void poly_genkey_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_genkey_continue);
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}
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static int poly_genkey(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct chacha_req *creq = &rctx->u.chacha;
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int err;
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sg_init_table(creq->src, 1);
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memset(creq->key, 0, sizeof(creq->key));
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sg_set_buf(creq->src, creq->key, sizeof(creq->key));
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chacha_iv(creq->iv, req, 0);
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ablkcipher_request_set_callback(&creq->req, aead_request_flags(req),
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poly_genkey_done, req);
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ablkcipher_request_set_tfm(&creq->req, ctx->chacha);
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ablkcipher_request_set_crypt(&creq->req, creq->src, creq->src,
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POLY1305_KEY_SIZE, creq->iv);
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err = crypto_ablkcipher_decrypt(&creq->req);
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if (err)
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return err;
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return poly_genkey_continue(req);
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}
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static void chacha_encrypt_done(struct crypto_async_request *areq, int err)
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{
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async_done_continue(areq->data, err, poly_genkey);
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}
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static int chacha_encrypt(struct aead_request *req)
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{
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struct chachapoly_ctx *ctx = crypto_aead_ctx(crypto_aead_reqtfm(req));
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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struct chacha_req *creq = &rctx->u.chacha;
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int err;
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chacha_iv(creq->iv, req, 1);
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ablkcipher_request_set_callback(&creq->req, aead_request_flags(req),
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chacha_encrypt_done, req);
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ablkcipher_request_set_tfm(&creq->req, ctx->chacha);
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ablkcipher_request_set_crypt(&creq->req, req->src, req->dst,
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req->cryptlen, creq->iv);
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err = crypto_ablkcipher_encrypt(&creq->req);
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if (err)
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return err;
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return poly_genkey(req);
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}
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static int chachapoly_encrypt(struct aead_request *req)
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{
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struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
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rctx->cryptlen = req->cryptlen;
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/* encrypt call chain:
|
||||
* - chacha_encrypt/done()
|
||||
* - poly_genkey/done/continue()
|
||||
* - poly_init/done()
|
||||
* - poly_ad/done()
|
||||
* - poly_adpad/done()
|
||||
* - poly_cipher/done()
|
||||
* - poly_cipherpad/done()
|
||||
* - poly_tail/done/continue()
|
||||
* - poly_copy_tag()
|
||||
*/
|
||||
return chacha_encrypt(req);
|
||||
}
|
||||
|
||||
static int chachapoly_decrypt(struct aead_request *req)
|
||||
{
|
||||
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
|
||||
|
||||
if (req->cryptlen < POLY1305_DIGEST_SIZE)
|
||||
return -EINVAL;
|
||||
rctx->cryptlen = req->cryptlen - POLY1305_DIGEST_SIZE;
|
||||
|
||||
/* decrypt call chain:
|
||||
* - poly_genkey/done/continue()
|
||||
* - poly_init/done()
|
||||
* - poly_ad/done()
|
||||
* - poly_adpad/done()
|
||||
* - poly_cipher/done()
|
||||
* - poly_cipherpad/done()
|
||||
* - poly_tail/done/continue()
|
||||
* - chacha_decrypt/done()
|
||||
* - poly_verify_tag()
|
||||
*/
|
||||
return poly_genkey(req);
|
||||
}
|
||||
|
||||
static int chachapoly_setkey(struct crypto_aead *aead, const u8 *key,
|
||||
unsigned int keylen)
|
||||
{
|
||||
struct chachapoly_ctx *ctx = crypto_aead_ctx(aead);
|
||||
int err;
|
||||
|
||||
if (keylen != ctx->saltlen + CHACHA20_KEY_SIZE)
|
||||
return -EINVAL;
|
||||
|
||||
keylen -= ctx->saltlen;
|
||||
memcpy(ctx->salt, key + keylen, ctx->saltlen);
|
||||
|
||||
crypto_ablkcipher_clear_flags(ctx->chacha, CRYPTO_TFM_REQ_MASK);
|
||||
crypto_ablkcipher_set_flags(ctx->chacha, crypto_aead_get_flags(aead) &
|
||||
CRYPTO_TFM_REQ_MASK);
|
||||
|
||||
err = crypto_ablkcipher_setkey(ctx->chacha, key, keylen);
|
||||
crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctx->chacha) &
|
||||
CRYPTO_TFM_RES_MASK);
|
||||
return err;
|
||||
}
|
||||
|
||||
static int chachapoly_setauthsize(struct crypto_aead *tfm,
|
||||
unsigned int authsize)
|
||||
{
|
||||
if (authsize != POLY1305_DIGEST_SIZE)
|
||||
return -EINVAL;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int chachapoly_init(struct crypto_tfm *tfm)
|
||||
{
|
||||
struct crypto_instance *inst = (void *)tfm->__crt_alg;
|
||||
struct chachapoly_instance_ctx *ictx = crypto_instance_ctx(inst);
|
||||
struct chachapoly_ctx *ctx = crypto_tfm_ctx(tfm);
|
||||
struct crypto_ablkcipher *chacha;
|
||||
struct crypto_ahash *poly;
|
||||
unsigned long align;
|
||||
|
||||
poly = crypto_spawn_ahash(&ictx->poly);
|
||||
if (IS_ERR(poly))
|
||||
return PTR_ERR(poly);
|
||||
|
||||
chacha = crypto_spawn_skcipher(&ictx->chacha);
|
||||
if (IS_ERR(chacha)) {
|
||||
crypto_free_ahash(poly);
|
||||
return PTR_ERR(chacha);
|
||||
}
|
||||
|
||||
ctx->chacha = chacha;
|
||||
ctx->poly = poly;
|
||||
ctx->saltlen = ictx->saltlen;
|
||||
|
||||
align = crypto_tfm_alg_alignmask(tfm);
|
||||
align &= ~(crypto_tfm_ctx_alignment() - 1);
|
||||
crypto_aead_set_reqsize(__crypto_aead_cast(tfm),
|
||||
align + offsetof(struct chachapoly_req_ctx, u) +
|
||||
max(offsetof(struct chacha_req, req) +
|
||||
sizeof(struct ablkcipher_request) +
|
||||
crypto_ablkcipher_reqsize(chacha),
|
||||
offsetof(struct poly_req, req) +
|
||||
sizeof(struct ahash_request) +
|
||||
crypto_ahash_reqsize(poly)));
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void chachapoly_exit(struct crypto_tfm *tfm)
|
||||
{
|
||||
struct chachapoly_ctx *ctx = crypto_tfm_ctx(tfm);
|
||||
|
||||
crypto_free_ahash(ctx->poly);
|
||||
crypto_free_ablkcipher(ctx->chacha);
|
||||
}
|
||||
|
||||
static struct crypto_instance *chachapoly_alloc(struct rtattr **tb,
|
||||
const char *name,
|
||||
unsigned int ivsize)
|
||||
{
|
||||
struct crypto_attr_type *algt;
|
||||
struct crypto_instance *inst;
|
||||
struct crypto_alg *chacha;
|
||||
struct crypto_alg *poly;
|
||||
struct ahash_alg *poly_ahash;
|
||||
struct chachapoly_instance_ctx *ctx;
|
||||
const char *chacha_name, *poly_name;
|
||||
int err;
|
||||
|
||||
if (ivsize > CHACHAPOLY_IV_SIZE)
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
algt = crypto_get_attr_type(tb);
|
||||
if (IS_ERR(algt))
|
||||
return ERR_CAST(algt);
|
||||
|
||||
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
|
||||
return ERR_PTR(-EINVAL);
|
||||
|
||||
chacha_name = crypto_attr_alg_name(tb[1]);
|
||||
if (IS_ERR(chacha_name))
|
||||
return ERR_CAST(chacha_name);
|
||||
poly_name = crypto_attr_alg_name(tb[2]);
|
||||
if (IS_ERR(poly_name))
|
||||
return ERR_CAST(poly_name);
|
||||
|
||||
poly = crypto_find_alg(poly_name, &crypto_ahash_type,
|
||||
CRYPTO_ALG_TYPE_HASH,
|
||||
CRYPTO_ALG_TYPE_AHASH_MASK);
|
||||
if (IS_ERR(poly))
|
||||
return ERR_CAST(poly);
|
||||
|
||||
err = -ENOMEM;
|
||||
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
|
||||
if (!inst)
|
||||
goto out_put_poly;
|
||||
|
||||
ctx = crypto_instance_ctx(inst);
|
||||
ctx->saltlen = CHACHAPOLY_IV_SIZE - ivsize;
|
||||
poly_ahash = container_of(poly, struct ahash_alg, halg.base);
|
||||
err = crypto_init_ahash_spawn(&ctx->poly, &poly_ahash->halg, inst);
|
||||
if (err)
|
||||
goto err_free_inst;
|
||||
|
||||
crypto_set_skcipher_spawn(&ctx->chacha, inst);
|
||||
err = crypto_grab_skcipher(&ctx->chacha, chacha_name, 0,
|
||||
crypto_requires_sync(algt->type,
|
||||
algt->mask));
|
||||
if (err)
|
||||
goto err_drop_poly;
|
||||
|
||||
chacha = crypto_skcipher_spawn_alg(&ctx->chacha);
|
||||
|
||||
err = -EINVAL;
|
||||
/* Need 16-byte IV size, including Initial Block Counter value */
|
||||
if (chacha->cra_ablkcipher.ivsize != CHACHA20_IV_SIZE)
|
||||
goto out_drop_chacha;
|
||||
/* Not a stream cipher? */
|
||||
if (chacha->cra_blocksize != 1)
|
||||
goto out_drop_chacha;
|
||||
|
||||
err = -ENAMETOOLONG;
|
||||
if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
|
||||
"%s(%s,%s)", name, chacha_name,
|
||||
poly_name) >= CRYPTO_MAX_ALG_NAME)
|
||||
goto out_drop_chacha;
|
||||
if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
|
||||
"%s(%s,%s)", name, chacha->cra_driver_name,
|
||||
poly->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
|
||||
goto out_drop_chacha;
|
||||
|
||||
inst->alg.cra_flags = CRYPTO_ALG_TYPE_AEAD;
|
||||
inst->alg.cra_flags |= (chacha->cra_flags |
|
||||
poly->cra_flags) & CRYPTO_ALG_ASYNC;
|
||||
inst->alg.cra_priority = (chacha->cra_priority +
|
||||
poly->cra_priority) / 2;
|
||||
inst->alg.cra_blocksize = 1;
|
||||
inst->alg.cra_alignmask = chacha->cra_alignmask | poly->cra_alignmask;
|
||||
inst->alg.cra_type = &crypto_nivaead_type;
|
||||
inst->alg.cra_aead.ivsize = ivsize;
|
||||
inst->alg.cra_aead.maxauthsize = POLY1305_DIGEST_SIZE;
|
||||
inst->alg.cra_ctxsize = sizeof(struct chachapoly_ctx) + ctx->saltlen;
|
||||
inst->alg.cra_init = chachapoly_init;
|
||||
inst->alg.cra_exit = chachapoly_exit;
|
||||
inst->alg.cra_aead.encrypt = chachapoly_encrypt;
|
||||
inst->alg.cra_aead.decrypt = chachapoly_decrypt;
|
||||
inst->alg.cra_aead.setkey = chachapoly_setkey;
|
||||
inst->alg.cra_aead.setauthsize = chachapoly_setauthsize;
|
||||
inst->alg.cra_aead.geniv = "seqiv";
|
||||
|
||||
out:
|
||||
crypto_mod_put(poly);
|
||||
return inst;
|
||||
|
||||
out_drop_chacha:
|
||||
crypto_drop_skcipher(&ctx->chacha);
|
||||
err_drop_poly:
|
||||
crypto_drop_ahash(&ctx->poly);
|
||||
err_free_inst:
|
||||
kfree(inst);
|
||||
out_put_poly:
|
||||
inst = ERR_PTR(err);
|
||||
goto out;
|
||||
}
|
||||
|
||||
static struct crypto_instance *rfc7539_alloc(struct rtattr **tb)
|
||||
{
|
||||
return chachapoly_alloc(tb, "rfc7539", 12);
|
||||
}
|
||||
|
||||
static void chachapoly_free(struct crypto_instance *inst)
|
||||
{
|
||||
struct chachapoly_instance_ctx *ctx = crypto_instance_ctx(inst);
|
||||
|
||||
crypto_drop_skcipher(&ctx->chacha);
|
||||
crypto_drop_ahash(&ctx->poly);
|
||||
kfree(inst);
|
||||
}
|
||||
|
||||
static struct crypto_template rfc7539_tmpl = {
|
||||
.name = "rfc7539",
|
||||
.alloc = rfc7539_alloc,
|
||||
.free = chachapoly_free,
|
||||
.module = THIS_MODULE,
|
||||
};
|
||||
|
||||
static int __init chacha20poly1305_module_init(void)
|
||||
{
|
||||
return crypto_register_template(&rfc7539_tmpl);
|
||||
}
|
||||
|
||||
static void __exit chacha20poly1305_module_exit(void)
|
||||
{
|
||||
crypto_unregister_template(&rfc7539_tmpl);
|
||||
}
|
||||
|
||||
module_init(chacha20poly1305_module_init);
|
||||
module_exit(chacha20poly1305_module_exit);
|
||||
|
||||
MODULE_LICENSE("GPL");
|
||||
MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");
|
||||
MODULE_DESCRIPTION("ChaCha20-Poly1305 AEAD");
|
||||
MODULE_ALIAS_CRYPTO("chacha20poly1305");
|
||||
MODULE_ALIAS_CRYPTO("rfc7539");
|
||||
Loading…
Reference in a new issue