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![Eric Biggers](/assets/img/avatar_default.png)
If the rfc7539 template was instantiated with a hash algorithm with
digest size larger than 16 bytes (POLY1305_DIGEST_SIZE), then the digest
overran the 'tag' buffer in 'struct chachapoly_req_ctx', corrupting the
subsequent memory, including 'cryptlen'. This caused a crash during
crypto_skcipher_decrypt().
Fix it by, when instantiating the template, requiring that the
underlying hash algorithm has the digest size expected for Poly1305.
Reproducer:
#include <linux/if_alg.h>
#include <sys/socket.h>
#include <unistd.h>
int main()
{
int algfd, reqfd;
struct sockaddr_alg addr = {
.salg_type = "aead",
.salg_name = "rfc7539(chacha20,sha256)",
};
unsigned char buf[32] = { 0 };
algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
bind(algfd, (void *)&addr, sizeof(addr));
setsockopt(algfd, SOL_ALG, ALG_SET_KEY, buf, sizeof(buf));
reqfd = accept(algfd, 0, 0);
write(reqfd, buf, 16);
read(reqfd, buf, 16);
}
Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 71ebc4d1b2
("crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539")
Cc: <stable@vger.kernel.org> # v4.2+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
746 lines
19 KiB
C
746 lines
19 KiB
C
/*
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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 <crypto/chacha20.h>
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#include <crypto/poly1305.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 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_skcipher *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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u8 iv[CHACHA20_IV_SIZE];
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struct scatterlist src[1];
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struct skcipher_request req; /* must be last member */
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};
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struct chachapoly_req_ctx {
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struct scatterlist src[2];
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struct scatterlist dst[2];
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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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/* 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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/* Actual AD, excluding IV */
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unsigned int assoclen;
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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,
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req->assoclen + rctx->cryptlen,
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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,
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req->assoclen + 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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struct scatterlist *src, *dst;
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int err;
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if (rctx->cryptlen == 0)
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goto skip;
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chacha_iv(creq->iv, req, 1);
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sg_init_table(rctx->src, 2);
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src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen);
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dst = src;
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if (req->src != req->dst) {
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sg_init_table(rctx->dst, 2);
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dst = scatterwalk_ffwd(rctx->dst, req->dst, req->assoclen);
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}
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skcipher_request_set_callback(&creq->req, aead_request_flags(req),
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chacha_decrypt_done, req);
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skcipher_request_set_tfm(&creq->req, ctx->chacha);
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skcipher_request_set_crypt(&creq->req, src, dst,
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rctx->cryptlen, creq->iv);
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err = crypto_skcipher_decrypt(&creq->req);
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if (err)
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return err;
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skip:
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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 crypto_aead *tfm = crypto_aead_reqtfm(req);
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struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
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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(rctx->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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sg_init_table(rctx->src, 2);
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crypt = scatterwalk_ffwd(rctx->src, crypt, req->assoclen);
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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 - (rctx->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->src, NULL, rctx->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_setkey_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_setkey(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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sg_init_table(preq->src, 1);
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sg_set_buf(preq->src, rctx->key, sizeof(rctx->key));
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ahash_request_set_callback(&preq->req, aead_request_flags(req),
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poly_setkey_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, sizeof(rctx->key));
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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_ad(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_setkey);
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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_setkey(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_init);
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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 crypto_aead *tfm = crypto_aead_reqtfm(req);
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struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
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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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rctx->assoclen = req->assoclen;
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if (crypto_aead_ivsize(tfm) == 8) {
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if (rctx->assoclen < 8)
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return -EINVAL;
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rctx->assoclen -= 8;
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}
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sg_init_table(creq->src, 1);
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memset(rctx->key, 0, sizeof(rctx->key));
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sg_set_buf(creq->src, rctx->key, sizeof(rctx->key));
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chacha_iv(creq->iv, req, 0);
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skcipher_request_set_callback(&creq->req, aead_request_flags(req),
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poly_genkey_done, req);
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skcipher_request_set_tfm(&creq->req, ctx->chacha);
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skcipher_request_set_crypt(&creq->req, creq->src, creq->src,
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POLY1305_KEY_SIZE, creq->iv);
|
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err = crypto_skcipher_decrypt(&creq->req);
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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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|
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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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struct scatterlist *src, *dst;
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int err;
|
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|
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if (req->cryptlen == 0)
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goto skip;
|
|
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chacha_iv(creq->iv, req, 1);
|
|
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sg_init_table(rctx->src, 2);
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src = scatterwalk_ffwd(rctx->src, req->src, req->assoclen);
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dst = src;
|
|
|
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if (req->src != req->dst) {
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sg_init_table(rctx->dst, 2);
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dst = scatterwalk_ffwd(rctx->dst, req->dst, req->assoclen);
|
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}
|
|
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skcipher_request_set_callback(&creq->req, aead_request_flags(req),
|
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chacha_encrypt_done, req);
|
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skcipher_request_set_tfm(&creq->req, ctx->chacha);
|
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skcipher_request_set_crypt(&creq->req, src, dst,
|
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req->cryptlen, creq->iv);
|
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err = crypto_skcipher_encrypt(&creq->req);
|
|
if (err)
|
|
return err;
|
|
|
|
skip:
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return poly_genkey(req);
|
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}
|
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|
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static int chachapoly_encrypt(struct aead_request *req)
|
|
{
|
|
struct chachapoly_req_ctx *rctx = aead_request_ctx(req);
|
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|
|
rctx->cryptlen = req->cryptlen;
|
|
|
|
/* encrypt call chain:
|
|
* - chacha_encrypt/done()
|
|
* - poly_genkey/done()
|
|
* - poly_init/done()
|
|
* - poly_setkey/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);
|
|
|
|
rctx->cryptlen = req->cryptlen - POLY1305_DIGEST_SIZE;
|
|
|
|
/* decrypt call chain:
|
|
* - poly_genkey/done()
|
|
* - poly_init/done()
|
|
* - poly_setkey/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_skcipher_clear_flags(ctx->chacha, CRYPTO_TFM_REQ_MASK);
|
|
crypto_skcipher_set_flags(ctx->chacha, crypto_aead_get_flags(aead) &
|
|
CRYPTO_TFM_REQ_MASK);
|
|
|
|
err = crypto_skcipher_setkey(ctx->chacha, key, keylen);
|
|
crypto_aead_set_flags(aead, crypto_skcipher_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_aead *tfm)
|
|
{
|
|
struct aead_instance *inst = aead_alg_instance(tfm);
|
|
struct chachapoly_instance_ctx *ictx = aead_instance_ctx(inst);
|
|
struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
|
|
struct crypto_skcipher *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_aead_alignmask(tfm);
|
|
align &= ~(crypto_tfm_ctx_alignment() - 1);
|
|
crypto_aead_set_reqsize(
|
|
tfm,
|
|
align + offsetof(struct chachapoly_req_ctx, u) +
|
|
max(offsetof(struct chacha_req, req) +
|
|
sizeof(struct skcipher_request) +
|
|
crypto_skcipher_reqsize(chacha),
|
|
offsetof(struct poly_req, req) +
|
|
sizeof(struct ahash_request) +
|
|
crypto_ahash_reqsize(poly)));
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void chachapoly_exit(struct crypto_aead *tfm)
|
|
{
|
|
struct chachapoly_ctx *ctx = crypto_aead_ctx(tfm);
|
|
|
|
crypto_free_ahash(ctx->poly);
|
|
crypto_free_skcipher(ctx->chacha);
|
|
}
|
|
|
|
static void chachapoly_free(struct aead_instance *inst)
|
|
{
|
|
struct chachapoly_instance_ctx *ctx = aead_instance_ctx(inst);
|
|
|
|
crypto_drop_skcipher(&ctx->chacha);
|
|
crypto_drop_ahash(&ctx->poly);
|
|
kfree(inst);
|
|
}
|
|
|
|
static int chachapoly_create(struct crypto_template *tmpl, struct rtattr **tb,
|
|
const char *name, unsigned int ivsize)
|
|
{
|
|
struct crypto_attr_type *algt;
|
|
struct aead_instance *inst;
|
|
struct skcipher_alg *chacha;
|
|
struct crypto_alg *poly;
|
|
struct hash_alg_common *poly_hash;
|
|
struct chachapoly_instance_ctx *ctx;
|
|
const char *chacha_name, *poly_name;
|
|
int err;
|
|
|
|
if (ivsize > CHACHAPOLY_IV_SIZE)
|
|
return -EINVAL;
|
|
|
|
algt = crypto_get_attr_type(tb);
|
|
if (IS_ERR(algt))
|
|
return PTR_ERR(algt);
|
|
|
|
if ((algt->type ^ CRYPTO_ALG_TYPE_AEAD) & algt->mask)
|
|
return -EINVAL;
|
|
|
|
chacha_name = crypto_attr_alg_name(tb[1]);
|
|
if (IS_ERR(chacha_name))
|
|
return PTR_ERR(chacha_name);
|
|
poly_name = crypto_attr_alg_name(tb[2]);
|
|
if (IS_ERR(poly_name))
|
|
return PTR_ERR(poly_name);
|
|
|
|
poly = crypto_find_alg(poly_name, &crypto_ahash_type,
|
|
CRYPTO_ALG_TYPE_HASH,
|
|
CRYPTO_ALG_TYPE_AHASH_MASK |
|
|
crypto_requires_sync(algt->type,
|
|
algt->mask));
|
|
if (IS_ERR(poly))
|
|
return PTR_ERR(poly);
|
|
poly_hash = __crypto_hash_alg_common(poly);
|
|
|
|
err = -EINVAL;
|
|
if (poly_hash->digestsize != POLY1305_DIGEST_SIZE)
|
|
goto out_put_poly;
|
|
|
|
err = -ENOMEM;
|
|
inst = kzalloc(sizeof(*inst) + sizeof(*ctx), GFP_KERNEL);
|
|
if (!inst)
|
|
goto out_put_poly;
|
|
|
|
ctx = aead_instance_ctx(inst);
|
|
ctx->saltlen = CHACHAPOLY_IV_SIZE - ivsize;
|
|
err = crypto_init_ahash_spawn(&ctx->poly, poly_hash,
|
|
aead_crypto_instance(inst));
|
|
if (err)
|
|
goto err_free_inst;
|
|
|
|
crypto_set_skcipher_spawn(&ctx->chacha, aead_crypto_instance(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_spawn_skcipher_alg(&ctx->chacha);
|
|
|
|
err = -EINVAL;
|
|
/* Need 16-byte IV size, including Initial Block Counter value */
|
|
if (crypto_skcipher_alg_ivsize(chacha) != CHACHA20_IV_SIZE)
|
|
goto out_drop_chacha;
|
|
/* Not a stream cipher? */
|
|
if (chacha->base.cra_blocksize != 1)
|
|
goto out_drop_chacha;
|
|
|
|
err = -ENAMETOOLONG;
|
|
if (snprintf(inst->alg.base.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.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
|
|
"%s(%s,%s)", name, chacha->base.cra_driver_name,
|
|
poly->cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
|
|
goto out_drop_chacha;
|
|
|
|
inst->alg.base.cra_flags = (chacha->base.cra_flags | poly->cra_flags) &
|
|
CRYPTO_ALG_ASYNC;
|
|
inst->alg.base.cra_priority = (chacha->base.cra_priority +
|
|
poly->cra_priority) / 2;
|
|
inst->alg.base.cra_blocksize = 1;
|
|
inst->alg.base.cra_alignmask = chacha->base.cra_alignmask |
|
|
poly->cra_alignmask;
|
|
inst->alg.base.cra_ctxsize = sizeof(struct chachapoly_ctx) +
|
|
ctx->saltlen;
|
|
inst->alg.ivsize = ivsize;
|
|
inst->alg.chunksize = crypto_skcipher_alg_chunksize(chacha);
|
|
inst->alg.maxauthsize = POLY1305_DIGEST_SIZE;
|
|
inst->alg.init = chachapoly_init;
|
|
inst->alg.exit = chachapoly_exit;
|
|
inst->alg.encrypt = chachapoly_encrypt;
|
|
inst->alg.decrypt = chachapoly_decrypt;
|
|
inst->alg.setkey = chachapoly_setkey;
|
|
inst->alg.setauthsize = chachapoly_setauthsize;
|
|
|
|
inst->free = chachapoly_free;
|
|
|
|
err = aead_register_instance(tmpl, inst);
|
|
if (err)
|
|
goto out_drop_chacha;
|
|
|
|
out_put_poly:
|
|
crypto_mod_put(poly);
|
|
return err;
|
|
|
|
out_drop_chacha:
|
|
crypto_drop_skcipher(&ctx->chacha);
|
|
err_drop_poly:
|
|
crypto_drop_ahash(&ctx->poly);
|
|
err_free_inst:
|
|
kfree(inst);
|
|
goto out_put_poly;
|
|
}
|
|
|
|
static int rfc7539_create(struct crypto_template *tmpl, struct rtattr **tb)
|
|
{
|
|
return chachapoly_create(tmpl, tb, "rfc7539", 12);
|
|
}
|
|
|
|
static int rfc7539esp_create(struct crypto_template *tmpl, struct rtattr **tb)
|
|
{
|
|
return chachapoly_create(tmpl, tb, "rfc7539esp", 8);
|
|
}
|
|
|
|
static struct crypto_template rfc7539_tmpl = {
|
|
.name = "rfc7539",
|
|
.create = rfc7539_create,
|
|
.module = THIS_MODULE,
|
|
};
|
|
|
|
static struct crypto_template rfc7539esp_tmpl = {
|
|
.name = "rfc7539esp",
|
|
.create = rfc7539esp_create,
|
|
.module = THIS_MODULE,
|
|
};
|
|
|
|
static int __init chacha20poly1305_module_init(void)
|
|
{
|
|
int err;
|
|
|
|
err = crypto_register_template(&rfc7539_tmpl);
|
|
if (err)
|
|
return err;
|
|
|
|
err = crypto_register_template(&rfc7539esp_tmpl);
|
|
if (err)
|
|
crypto_unregister_template(&rfc7539_tmpl);
|
|
|
|
return err;
|
|
}
|
|
|
|
static void __exit chacha20poly1305_module_exit(void)
|
|
{
|
|
crypto_unregister_template(&rfc7539esp_tmpl);
|
|
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("rfc7539");
|
|
MODULE_ALIAS_CRYPTO("rfc7539esp");
|