static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req,
int enc)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
struct aead_request *subreq = &rctx->subreq;
struct scatterlist *dst = req->dst;
struct scatterlist *cipher = rctx->cipher;
struct scatterlist *payload = rctx->payload;
struct scatterlist *assoc = rctx->assoc;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int assoclen = req->assoclen;
struct page *dstp;
u8 *vdst;
u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
crypto_aead_alignmask(ctx->child) + 1);
memcpy(iv, ctx->nonce, 4);
memcpy(iv + 4, req->iv, 8);
/* construct cipher/plaintext */
if (enc)
memset(rctx->auth_tag, 0, authsize);
else
scatterwalk_map_and_copy(rctx->auth_tag, dst,
req->cryptlen - authsize,
authsize, 0);
sg_init_one(cipher, rctx->auth_tag, authsize);
/* construct the aad */
dstp = sg_page(dst);
vdst = PageHighMem(dstp) ? NULL : page_address(dstp) + dst->offset;
sg_init_table(payload, 2);
sg_set_buf(payload, req->iv, 8);
scatterwalk_crypto_chain(payload, dst, vdst == req->iv + 8, 2);
assoclen += 8 + req->cryptlen - (enc ? 0 : authsize);
sg_init_table(assoc, 2);
sg_set_page(assoc, sg_page(req->assoc), req->assoc->length,
req->assoc->offset);
scatterwalk_crypto_chain(assoc, payload, 0, 2);
aead_request_set_tfm(subreq, ctx->child);
aead_request_set_callback(subreq, req->base.flags, req->base.complete,
req->base.data);
aead_request_set_crypt(subreq, cipher, cipher, enc ? 0 : authsize, iv);
aead_request_set_assoc(subreq, assoc, assoclen);
return subreq;
}
static int crypto_rfc4543_copy_src_to_dst(struct aead_request *req, bool enc)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int nbytes = req->cryptlen - (enc ? 0 : authsize);
struct blkcipher_desc desc = {
.tfm = ctx->null,
};
return crypto_blkcipher_encrypt(&desc, req->dst, req->src, nbytes);
}
static int crypto_rfc4543_encrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
struct aead_request *subreq;
int err;
if (req->src != req->dst) {
err = crypto_rfc4543_copy_src_to_dst(req, true);
if (err)
return err;
}
subreq = crypto_rfc4543_crypt(req, true);
err = crypto_aead_encrypt(subreq);
if (err)
return err;
scatterwalk_map_and_copy(rctx->auth_tag, req->dst, req->cryptlen,
crypto_aead_authsize(aead), 1);
return 0;
}
static int crypto_rfc4543_decrypt(struct aead_request *req)
{
int err;
if (req->src != req->dst) {
err = crypto_rfc4543_copy_src_to_dst(req, false);
if (err)
return err;
}
req = crypto_rfc4543_crypt(req, false);
return crypto_aead_decrypt(req);
}
static void crypto_rfc4543_done(struct crypto_async_request *areq, int err)
{
struct aead_request *req = areq->data;
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
if (!err) {
scatterwalk_map_and_copy(rctx->auth_tag, req->dst,
req->cryptlen,
crypto_aead_authsize(aead), 1);
}
aead_request_complete(req, err);
}
static int crypto_rfc4543_encrypt(struct aead_request *req)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
struct aead_request *subreq;
int err;
subreq = crypto_rfc4543_crypt(req, 1);
err = crypto_aead_encrypt(subreq);
if (err)
return err;
scatterwalk_map_and_copy(rctx->auth_tag, req->dst, req->cryptlen,
crypto_aead_authsize(aead), 1);
return 0;
}
static struct aead_request *crypto_rfc4543_crypt(struct aead_request *req,
bool enc)
{
struct crypto_aead *aead = crypto_aead_reqtfm(req);
struct crypto_rfc4543_ctx *ctx = crypto_aead_ctx(aead);
struct crypto_rfc4543_req_ctx *rctx = crypto_rfc4543_reqctx(req);
struct aead_request *subreq = &rctx->subreq;
struct scatterlist *src = req->src;
struct scatterlist *cipher = rctx->cipher;
struct scatterlist *payload = rctx->payload;
struct scatterlist *assoc = rctx->assoc;
unsigned int authsize = crypto_aead_authsize(aead);
unsigned int assoclen = req->assoclen;
struct page *srcp;
u8 *vsrc;
u8 *iv = PTR_ALIGN((u8 *)(rctx + 1) + crypto_aead_reqsize(ctx->child),
crypto_aead_alignmask(ctx->child) + 1);
memcpy(iv, ctx->nonce, 4);
memcpy(iv + 4, req->iv, 8);
/* construct cipher/plaintext */
if (enc)
memset(rctx->auth_tag, 0, authsize);
else
scatterwalk_map_and_copy(rctx->auth_tag, src,
req->cryptlen - authsize,
authsize, 0);
sg_init_one(cipher, rctx->auth_tag, authsize);
/* construct the aad */
srcp = sg_page(src);
vsrc = PageHighMem(srcp) ? NULL : page_address(srcp) + src->offset;
sg_init_table(payload, 2);
sg_set_buf(payload, req->iv, 8);
scatterwalk_crypto_chain(payload, src, vsrc == req->iv + 8, 2);
assoclen += 8 + req->cryptlen - (enc ? 0 : authsize);
if (req->assoc->length == req->assoclen) {
sg_init_table(assoc, 2);
sg_set_page(assoc, sg_page(req->assoc), req->assoc->length,
req->assoc->offset);
} else {
BUG_ON(req->assoclen > sizeof(rctx->assocbuf));
scatterwalk_map_and_copy(rctx->assocbuf, req->assoc, 0,
req->assoclen, 0);
sg_init_table(assoc, 2);
sg_set_buf(assoc, rctx->assocbuf, req->assoclen);
}
scatterwalk_crypto_chain(assoc, payload, 0, 2);
aead_request_set_tfm(subreq, ctx->child);
aead_request_set_callback(subreq, req->base.flags, crypto_rfc4543_done,
req);
aead_request_set_crypt(subreq, cipher, cipher, enc ? 0 : authsize, iv);
aead_request_set_assoc(subreq, assoc, assoclen);
return subreq;
}
