[v2 PATCH 13/13] crypto: algif_aead - Switch to new AEAD interface

Herbert Xu
2015-05-22T08:31:09Z

This patch makes use of the new AEAD interface which uses a single
SG list instead of separate lists for the AD and plain text.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---

crypto/algif_aead.c | 61 ++++++++++++++++++++++++++++++----------------------
1 file changed, 36 insertions(+), 25 deletions(-)

diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index 53702e9..5674a33 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -26,7 +26,7 @@

struct aead_sg_list {
unsigned int cur;
- struct scatterlist sg[ALG_MAX_PAGES];
+ struct scatterlist sg[ALG_MAX_PAGES + 1];
};

struct aead_ctx {
@@ -357,7 +357,8 @@ static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored,
unsigned as = crypto_aead_authsize(crypto_aead_reqtfm(&ctx->aead_req));
struct aead_sg_list *sgl = &ctx->tsgl;
struct scatterlist *sg = NULL;
- struct scatterlist assoc[ALG_MAX_PAGES];
+ struct scatterlist dstbuf[ALG_MAX_PAGES + 1];
+ struct scatterlist *dst = dstbuf;
size_t assoclen = 0;
unsigned int i = 0;
int err = -EINVAL;
@@ -453,7 +454,7 @@ static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored,
if (usedpages < outlen)
goto unlock;

- sg_init_table(assoc, ALG_MAX_PAGES);
+ sg_mark_end(sgl->sg + sgl->cur);
assoclen = ctx->aead_assoclen;
/*
* Split scatterlist into two: first part becomes AD, second part
@@ -465,35 +466,45 @@ static int aead_recvmsg(struct socket *sock, struct msghdr *msg, size_t ignored,
sg = sgl->sg + i;
if (sg->length <= assoclen) {
/* AD is larger than one page */
- sg_set_page(assoc + i, sg_page(sg),
+ sg_set_page(dst + i, sg_page(sg),
sg->length, sg->offset);
assoclen -= sg->length;
- if (i >= ctx->tsgl.cur)
- goto unlock;
- } else if (!assoclen) {
- /* current page is to start of plaintext / ciphertext */
- if (i)
- /* AD terminates at page boundary */
- sg_mark_end(assoc + i - 1);
- else
- /* AD size is zero */
- sg_mark_end(assoc);
- break;
- } else {
+ continue;
+ }
+
+ if (assoclen) {
/* AD does not terminate at page boundary */
- sg_set_page(assoc + i, sg_page(sg),
+ sg_set_page(dst + i, sg_page(sg),
assoclen, sg->offset);
- sg_mark_end(assoc + i);
- /* plaintext / ciphertext starts after AD */
- sg->length -= assoclen;
- sg->offset += assoclen;
- break;
+ assoclen = 0;
+ i++;
}
+
+ break;
}

- aead_request_set_assoc(&ctx->aead_req, assoc, ctx->aead_assoclen);
- aead_request_set_crypt(&ctx->aead_req, sg, ctx->rsgl[0].sg, used,
- ctx->iv);
+ /* This should never happen because of aead_sufficient_data. */
+ if (WARN_ON_ONCE(assoclen))
+ goto unlock;
+
+ /* current page is the start of plaintext / ciphertext */
+ if (!i)
+ /* AD size is zero */
+ dst = ctx->rsgl[0].sg;
+ else if (outlen)
+ /* AD size is non-zero */
+ scatterwalk_crypto_chain(
+ dst, ctx->rsgl[0].sg,
+ sg_page(ctx->rsgl[0].sg) == sg_page(dst + i - 1) &&
+ ctx->rsgl[0].sg[0].offset == dst[i - 1].offset +
+ dst[i - 1].length,
+ i + 1);
+ else
+ /* AD only */
+ sg_mark_end(dst + i);
+
+ aead_request_set_crypt(&ctx->aead_req, sgl->sg, dst, used, ctx->iv);
+ aead_request_set_ad(&ctx->aead_req, ctx->aead_assoclen, 0);

err = af_alg_wait_for_completion(ctx->enc ?