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>tirimbino
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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:
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* - chacha_encrypt/done() |
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* - poly_genkey/done/continue() |
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* - poly_init/done() |
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* - poly_ad/done() |
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* - poly_adpad/done() |
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* - poly_cipher/done() |
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* - poly_cipherpad/done() |
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* - poly_tail/done/continue() |
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* - poly_copy_tag() |
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*/ |
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return chacha_encrypt(req); |
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} |
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static int chachapoly_decrypt(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 (req->cryptlen < POLY1305_DIGEST_SIZE) |
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return -EINVAL; |
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rctx->cryptlen = req->cryptlen - POLY1305_DIGEST_SIZE; |
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/* decrypt call chain:
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* - poly_genkey/done/continue() |
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* - poly_init/done() |
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* - poly_ad/done() |
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* - poly_adpad/done() |
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* - poly_cipher/done() |
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* - poly_cipherpad/done() |
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* - poly_tail/done/continue() |
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* - chacha_decrypt/done() |
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* - poly_verify_tag() |
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*/ |
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return poly_genkey(req); |
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} |
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static int chachapoly_setkey(struct crypto_aead *aead, const u8 *key, |
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unsigned int keylen) |
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{ |
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struct chachapoly_ctx *ctx = crypto_aead_ctx(aead); |
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int err; |
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if (keylen != ctx->saltlen + CHACHA20_KEY_SIZE) |
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return -EINVAL; |
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keylen -= ctx->saltlen; |
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memcpy(ctx->salt, key + keylen, ctx->saltlen); |
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crypto_ablkcipher_clear_flags(ctx->chacha, CRYPTO_TFM_REQ_MASK); |
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crypto_ablkcipher_set_flags(ctx->chacha, crypto_aead_get_flags(aead) & |
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CRYPTO_TFM_REQ_MASK); |
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err = crypto_ablkcipher_setkey(ctx->chacha, key, keylen); |
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crypto_aead_set_flags(aead, crypto_ablkcipher_get_flags(ctx->chacha) & |
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CRYPTO_TFM_RES_MASK); |
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return err; |
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} |
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static int chachapoly_setauthsize(struct crypto_aead *tfm, |
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unsigned int authsize) |
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{ |
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if (authsize != POLY1305_DIGEST_SIZE) |
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return -EINVAL; |
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return 0; |
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} |
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static int chachapoly_init(struct crypto_tfm *tfm) |
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{ |
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struct crypto_instance *inst = (void *)tfm->__crt_alg; |
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struct chachapoly_instance_ctx *ictx = crypto_instance_ctx(inst); |
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struct chachapoly_ctx *ctx = crypto_tfm_ctx(tfm); |
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struct crypto_ablkcipher *chacha; |
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struct crypto_ahash *poly; |
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unsigned long align; |
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poly = crypto_spawn_ahash(&ictx->poly); |
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if (IS_ERR(poly)) |
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return PTR_ERR(poly); |
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chacha = crypto_spawn_skcipher(&ictx->chacha); |
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if (IS_ERR(chacha)) { |
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crypto_free_ahash(poly); |
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return PTR_ERR(chacha); |
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} |
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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 new issue