net: tls: Refactor tls aad space size calculation

TLS 1.3 has a different AAD size, use a variable in the code to
make TLS 1.3 support easy.

Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tls.h b/include/net/tls.h
index da616db484139c85cb01363d18992c8ab706920f..754b130672f0a29a057139888d5c18060a6bc95e 100644 (file)
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -202,6 +202,7 @@ struct cipher_context {
        char *iv;
        u16 rec_seq_size;
        char *rec_seq;
+       u16 aad_size;
 };
 
 union tls_crypto_context {

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 9326c06c2ffeef6bbd86c5ba099d3d023a101625..7b6386f4c685f442382a8dda344bec764f347b7f 100644 (file)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -185,7 +185,7 @@ static int tls_do_decryption(struct sock *sk,
        int ret;
 
        aead_request_set_tfm(aead_req, ctx->aead_recv);
-       aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE);
+       aead_request_set_ad(aead_req, tls_ctx->rx.aad_size);
        aead_request_set_crypt(aead_req, sgin, sgout,
                               data_len + tls_ctx->rx.tag_size,
                               (u8 *)iv_recv);
@@ -289,12 +289,12 @@ static struct tls_rec *tls_get_rec(struct sock *sk)
 
        sg_init_table(rec->sg_aead_in, 2);
        sg_set_buf(&rec->sg_aead_in[0], rec->aad_space,
-                  sizeof(rec->aad_space));
+                  tls_ctx->tx.aad_size);
        sg_unmark_end(&rec->sg_aead_in[1]);
 
        sg_init_table(rec->sg_aead_out, 2);
        sg_set_buf(&rec->sg_aead_out[0], rec->aad_space,
-                  sizeof(rec->aad_space));
+                  tls_ctx->tx.aad_size);
        sg_unmark_end(&rec->sg_aead_out[1]);
 
        return rec;
@@ -455,7 +455,7 @@ static int tls_do_encryption(struct sock *sk,
        msg_en->sg.curr = start;
 
        aead_request_set_tfm(aead_req, ctx->aead_send);
-       aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE);
+       aead_request_set_ad(aead_req, tls_ctx->tx.aad_size);
        aead_request_set_crypt(aead_req, rec->sg_aead_in,
                               rec->sg_aead_out,
                               data_len, rec->iv_data);
@@ -1317,7 +1317,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 
        aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv);
        mem_size = aead_size + (nsg * sizeof(struct scatterlist));
-       mem_size = mem_size + TLS_AAD_SPACE_SIZE;
+       mem_size = mem_size + tls_ctx->rx.aad_size;
        mem_size = mem_size + crypto_aead_ivsize(ctx->aead_recv);
 
        /* Allocate a single block of memory which contains
@@ -1333,7 +1333,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
        sgin = (struct scatterlist *)(mem + aead_size);
        sgout = sgin + n_sgin;
        aad = (u8 *)(sgout + n_sgout);
-       iv = aad + TLS_AAD_SPACE_SIZE;
+       iv = aad + tls_ctx->rx.aad_size;
 
        /* Prepare IV */
        err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE,
@@ -1352,7 +1352,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
 
        /* Prepare sgin */
        sg_init_table(sgin, n_sgin);
-       sg_set_buf(&sgin[0], aad, TLS_AAD_SPACE_SIZE);
+       sg_set_buf(&sgin[0], aad, tls_ctx->rx.aad_size);
        err = skb_to_sgvec(skb, &sgin[1],
                           rxm->offset + tls_ctx->rx.prepend_size,
                           rxm->full_len - tls_ctx->rx.prepend_size);
@@ -1364,7 +1364,7 @@ static int decrypt_internal(struct sock *sk, struct sk_buff *skb,
        if (n_sgout) {
                if (out_iov) {
                        sg_init_table(sgout, n_sgout);
-                       sg_set_buf(&sgout[0], aad, TLS_AAD_SPACE_SIZE);
+                       sg_set_buf(&sgout[0], aad, tls_ctx->rx.aad_size);
 
                        *chunk = 0;
                        err = tls_setup_from_iter(sk, out_iov, data_len,
@@ -2100,6 +2100,7 @@ int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx)
                goto free_priv;
        }
 
+       cctx->aad_size = TLS_AAD_SPACE_SIZE;
        cctx->prepend_size = TLS_HEADER_SIZE + nonce_size;
        cctx->tag_size = tag_size;
        cctx->overhead_size = cctx->prepend_size + cctx->tag_size;