tls: Remove redundant vars from tls record structure

Structure 'tls_rec' contains sg_aead_in and sg_aead_out which point
to a aad_space and then chain scatterlists sg_plaintext_data,
sg_encrypted_data respectively. Rather than using chained scatterlists
for plaintext and encrypted data in aead_req, it is efficient to store
aad_space in sg_encrypted_data and sg_plaintext_data itself in the
first index and get rid of sg_aead_in, sg_aead_in and further chaining.

This requires increasing size of sg_encrypted_data & sg_plaintext_data
arrarys by 1 to accommodate entry for aad_space. The code which uses
sg_encrypted_data and sg_plaintext_data has been modified to skip first
index as it points to aad_space.

Signed-off-by: Vakul Garg <vakul.garg@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/tls.h b/include/net/tls.h
index 1615fb5ea11443c17be45885257f83ff878ca36f..262420cdad100bf771fec969545cd1468e8866c8 100644 (file)
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -101,13 +101,11 @@ struct tls_rec {
        struct list_head list;
        int tx_ready;
        int tx_flags;
-       struct scatterlist sg_plaintext_data[MAX_SKB_FRAGS];
-       struct scatterlist sg_encrypted_data[MAX_SKB_FRAGS];
 
        /* AAD | sg_plaintext_data | sg_tag */
-       struct scatterlist sg_aead_in[2];
+       struct scatterlist sg_plaintext_data[MAX_SKB_FRAGS + 1];
        /* AAD | sg_encrypted_data (data contain overhead for hdr&iv&tag) */
-       struct scatterlist sg_aead_out[2];
+       struct scatterlist sg_encrypted_data[MAX_SKB_FRAGS + 1];
 
        unsigned int sg_plaintext_size;
        unsigned int sg_encrypted_size;

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 2176678a5b690820cd0de6c589e6a2d13a53917a..1d4c354d5516a64e9edeb5518ac58831ab1a3c02 100644 (file)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -248,7 +248,7 @@ static void trim_both_sgl(struct sock *sk, int target_size)
        struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
        struct tls_rec *rec = ctx->open_rec;
 
-       trim_sg(sk, rec->sg_plaintext_data,
+       trim_sg(sk, &rec->sg_plaintext_data[1],
                &rec->sg_plaintext_num_elem,
                &rec->sg_plaintext_size,
                target_size);
@@ -256,7 +256,7 @@ static void trim_both_sgl(struct sock *sk, int target_size)
        if (target_size > 0)
                target_size += tls_ctx->tx.overhead_size;
 
-       trim_sg(sk, rec->sg_encrypted_data,
+       trim_sg(sk, &rec->sg_encrypted_data[1],
                &rec->sg_encrypted_num_elem,
                &rec->sg_encrypted_size,
                target_size);
@@ -270,12 +270,13 @@ static int alloc_encrypted_sg(struct sock *sk, int len)
        int rc = 0;
 
        rc = sk_alloc_sg(sk, len,
-                        rec->sg_encrypted_data, 0,
+                        &rec->sg_encrypted_data[1], 0,
                         &rec->sg_encrypted_num_elem,
                         &rec->sg_encrypted_size, 0);
 
        if (rc == -ENOSPC)
-               rec->sg_encrypted_num_elem = ARRAY_SIZE(rec->sg_encrypted_data);
+               rec->sg_encrypted_num_elem =
+                       ARRAY_SIZE(rec->sg_encrypted_data) - 1;
 
        return rc;
 }
@@ -287,12 +288,15 @@ static int alloc_plaintext_sg(struct sock *sk, int len)
        struct tls_rec *rec = ctx->open_rec;
        int rc = 0;
 
-       rc = sk_alloc_sg(sk, len, rec->sg_plaintext_data, 0,
-                        &rec->sg_plaintext_num_elem, &rec->sg_plaintext_size,
+       rc = sk_alloc_sg(sk, len,
+                        &rec->sg_plaintext_data[1], 0,
+                        &rec->sg_plaintext_num_elem,
+                        &rec->sg_plaintext_size,
                         tls_ctx->pending_open_record_frags);
 
        if (rc == -ENOSPC)
-               rec->sg_plaintext_num_elem = ARRAY_SIZE(rec->sg_plaintext_data);
+               rec->sg_plaintext_num_elem =
+                       ARRAY_SIZE(rec->sg_plaintext_data) - 1;
 
        return rc;
 }
@@ -320,11 +324,11 @@ static void tls_free_open_rec(struct sock *sk)
        if (!rec)
                return;
 
-       free_sg(sk, rec->sg_encrypted_data,
+       free_sg(sk, &rec->sg_encrypted_data[1],
                &rec->sg_encrypted_num_elem,
                &rec->sg_encrypted_size);
 
-       free_sg(sk, rec->sg_plaintext_data,
+       free_sg(sk, &rec->sg_plaintext_data[1],
                &rec->sg_plaintext_num_elem,
                &rec->sg_plaintext_size);
 
@@ -355,7 +359,7 @@ int tls_tx_records(struct sock *sk, int flags)
                 * Remove the head of tx_list
                 */
                list_del(&rec->list);
-               free_sg(sk, rec->sg_plaintext_data,
+               free_sg(sk, &rec->sg_plaintext_data[1],
                        &rec->sg_plaintext_num_elem, &rec->sg_plaintext_size);
 
                kfree(rec);
@@ -370,13 +374,13 @@ int tls_tx_records(struct sock *sk, int flags)
                                tx_flags = flags;
 
                        rc = tls_push_sg(sk, tls_ctx,
-                                        &rec->sg_encrypted_data[0],
+                                        &rec->sg_encrypted_data[1],
                                         0, tx_flags);
                        if (rc)
                                goto tx_err;
 
                        list_del(&rec->list);
-                       free_sg(sk, rec->sg_plaintext_data,
+                       free_sg(sk, &rec->sg_plaintext_data[1],
                                &rec->sg_plaintext_num_elem,
                                &rec->sg_plaintext_size);
 
@@ -405,16 +409,12 @@ static void tls_encrypt_done(struct crypto_async_request *req, int err)
 
        rec = container_of(aead_req, struct tls_rec, aead_req);
 
-       rec->sg_encrypted_data[0].offset -= tls_ctx->tx.prepend_size;
-       rec->sg_encrypted_data[0].length += tls_ctx->tx.prepend_size;
+       rec->sg_encrypted_data[1].offset -= tls_ctx->tx.prepend_size;
+       rec->sg_encrypted_data[1].length += tls_ctx->tx.prepend_size;
 
 
-       /* Free the record if error is previously set on socket */
+       /* Check if error is previously set on socket */
        if (err || sk->sk_err) {
-               free_sg(sk, rec->sg_encrypted_data,
-                       &rec->sg_encrypted_num_elem, &rec->sg_encrypted_size);
-
-               kfree(rec);
                rec = NULL;
 
                /* If err is already set on socket, return the same code */
@@ -449,7 +449,7 @@ static void tls_encrypt_done(struct crypto_async_request *req, int err)
 
        /* Schedule the transmission */
        if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask))
-               schedule_delayed_work(&ctx->tx_work.work, 1);
+               schedule_delayed_work(&ctx->tx_work.work, 2);
 }
 
 static int tls_do_encryption(struct sock *sk,
@@ -461,13 +461,14 @@ static int tls_do_encryption(struct sock *sk,
        struct tls_rec *rec = ctx->open_rec;
        int rc;
 
-       rec->sg_encrypted_data[0].offset += tls_ctx->tx.prepend_size;
-       rec->sg_encrypted_data[0].length -= tls_ctx->tx.prepend_size;
+       /* Skip the first index as it contains AAD data */
+       rec->sg_encrypted_data[1].offset += tls_ctx->tx.prepend_size;
+       rec->sg_encrypted_data[1].length -= tls_ctx->tx.prepend_size;
 
        aead_request_set_tfm(aead_req, ctx->aead_send);
        aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE);
-       aead_request_set_crypt(aead_req, rec->sg_aead_in,
-                              rec->sg_aead_out,
+       aead_request_set_crypt(aead_req, rec->sg_plaintext_data,
+                              rec->sg_encrypted_data,
                               data_len, tls_ctx->tx.iv);
 
        aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG,
@@ -480,8 +481,8 @@ static int tls_do_encryption(struct sock *sk,
        rc = crypto_aead_encrypt(aead_req);
        if (!rc || rc != -EINPROGRESS) {
                atomic_dec(&ctx->encrypt_pending);
-               rec->sg_encrypted_data[0].offset -= tls_ctx->tx.prepend_size;
-               rec->sg_encrypted_data[0].length += tls_ctx->tx.prepend_size;
+               rec->sg_encrypted_data[1].offset -= tls_ctx->tx.prepend_size;
+               rec->sg_encrypted_data[1].length += tls_ctx->tx.prepend_size;
        }
 
        if (!rc) {
@@ -512,16 +513,16 @@ static int tls_push_record(struct sock *sk, int flags,
        rec->tx_flags = flags;
        req = &rec->aead_req;
 
-       sg_mark_end(rec->sg_plaintext_data + rec->sg_plaintext_num_elem - 1);
-       sg_mark_end(rec->sg_encrypted_data + rec->sg_encrypted_num_elem - 1);
+       sg_mark_end(rec->sg_plaintext_data + rec->sg_plaintext_num_elem);
+       sg_mark_end(rec->sg_encrypted_data + rec->sg_encrypted_num_elem);
 
        tls_make_aad(rec->aad_space, rec->sg_plaintext_size,
                     tls_ctx->tx.rec_seq, tls_ctx->tx.rec_seq_size,
                     record_type);
 
        tls_fill_prepend(tls_ctx,
-                        page_address(sg_page(&rec->sg_encrypted_data[0])) +
-                        rec->sg_encrypted_data[0].offset,
+                        page_address(sg_page(&rec->sg_encrypted_data[1])) +
+                        rec->sg_encrypted_data[1].offset,
                         rec->sg_plaintext_size, record_type);
 
        tls_ctx->pending_open_record_frags = 0;
@@ -613,7 +614,7 @@ static int memcopy_from_iter(struct sock *sk, struct iov_iter *from,
        struct tls_context *tls_ctx = tls_get_ctx(sk);
        struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx);
        struct tls_rec *rec = ctx->open_rec;
-       struct scatterlist *sg = rec->sg_plaintext_data;
+       struct scatterlist *sg = &rec->sg_plaintext_data[1];
        int copy, i, rc = 0;
 
        for (i = tls_ctx->pending_open_record_frags;
@@ -659,17 +660,10 @@ static struct tls_rec *get_rec(struct sock *sk)
        sg_init_table(&rec->sg_encrypted_data[0],
                      ARRAY_SIZE(rec->sg_encrypted_data));
 
-       sg_init_table(rec->sg_aead_in, 2);
-       sg_set_buf(&rec->sg_aead_in[0], rec->aad_space,
+       sg_set_buf(&rec->sg_plaintext_data[0], rec->aad_space,
                   sizeof(rec->aad_space));
-       sg_unmark_end(&rec->sg_aead_in[1]);
-       sg_chain(rec->sg_aead_in, 2, rec->sg_plaintext_data);
-
-       sg_init_table(rec->sg_aead_out, 2);
-       sg_set_buf(&rec->sg_aead_out[0], rec->aad_space,
+       sg_set_buf(&rec->sg_encrypted_data[0], rec->aad_space,
                   sizeof(rec->aad_space));
-       sg_unmark_end(&rec->sg_aead_out[1]);
-       sg_chain(rec->sg_aead_out, 2, rec->sg_encrypted_data);
 
        ctx->open_rec = rec;
 
@@ -763,8 +757,8 @@ alloc_encrypted:
                        ret = zerocopy_from_iter(sk, &msg->msg_iter,
                                try_to_copy, &rec->sg_plaintext_num_elem,
                                &rec->sg_plaintext_size,
-                               rec->sg_plaintext_data,
-                               ARRAY_SIZE(rec->sg_plaintext_data),
+                               &rec->sg_plaintext_data[1],
+                               ARRAY_SIZE(rec->sg_plaintext_data) - 1,
                                true);
                        if (ret)
                                goto fallback_to_reg_send;
@@ -781,7 +775,7 @@ alloc_encrypted:
                        continue;
 
 fallback_to_reg_send:
-                       trim_sg(sk, rec->sg_plaintext_data,
+                       trim_sg(sk, &rec->sg_plaintext_data[1],
                                &rec->sg_plaintext_num_elem,
                                &rec->sg_plaintext_size,
                                orig_size);
@@ -801,7 +795,7 @@ alloc_plaintext:
                        try_to_copy -= required_size - rec->sg_plaintext_size;
                        full_record = true;
 
-                       trim_sg(sk, rec->sg_encrypted_data,
+                       trim_sg(sk, &rec->sg_encrypted_data[1],
                                &rec->sg_encrypted_num_elem,
                                &rec->sg_encrypted_size,
                                rec->sg_plaintext_size +
@@ -949,7 +943,7 @@ alloc_payload:
                }
 
                get_page(page);
-               sg = rec->sg_plaintext_data + rec->sg_plaintext_num_elem;
+               sg = &rec->sg_plaintext_data[1] + rec->sg_plaintext_num_elem;
                sg_set_page(sg, page, copy, offset);
                sg_unmark_end(sg);
 
@@ -963,7 +957,7 @@ alloc_payload:
 
                if (full_record || eor ||
                    rec->sg_plaintext_num_elem ==
-                   ARRAY_SIZE(rec->sg_plaintext_data)) {
+                   ARRAY_SIZE(rec->sg_plaintext_data) - 1) {
                        ret = tls_push_record(sk, flags, record_type);
                        if (ret) {
                                if (ret == -EINPROGRESS)
@@ -1571,7 +1565,7 @@ void tls_sw_free_resources_tx(struct sock *sk)
                rec = list_first_entry(&ctx->tx_list,
                                       struct tls_rec, list);
 
-               free_sg(sk, rec->sg_plaintext_data,
+               free_sg(sk, &rec->sg_plaintext_data[1],
                        &rec->sg_plaintext_num_elem,
                        &rec->sg_plaintext_size);
 
@@ -1580,11 +1574,11 @@ void tls_sw_free_resources_tx(struct sock *sk)
        }
 
        list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) {
-               free_sg(sk, rec->sg_encrypted_data,
+               free_sg(sk, &rec->sg_encrypted_data[1],
                        &rec->sg_encrypted_num_elem,
                        &rec->sg_encrypted_size);
 
-               free_sg(sk, rec->sg_plaintext_data,
+               free_sg(sk, &rec->sg_plaintext_data[1],
                        &rec->sg_plaintext_num_elem,
                        &rec->sg_plaintext_size);