net: tls: Refactor control message handling on recv

For TLS 1.3, the control message is encrypted.  Handle control
message checks after decryption.

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

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 7b6386f4c685f442382a8dda344bec764f347b7f..34f3523f668e308cb743e75c572e1511aec19a32 100644 (file)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -1421,16 +1421,15 @@ static int decrypt_skb_update(struct sock *sk, struct sk_buff *skb,
 
                        return err;
                }
+               rxm->offset += tls_ctx->rx.prepend_size;
+               rxm->full_len -= tls_ctx->rx.overhead_size;
+               tls_advance_record_sn(sk, &tls_ctx->rx);
+               ctx->decrypted = true;
+               ctx->saved_data_ready(sk);
        } else {
                *zc = false;
        }
 
-       rxm->offset += tls_ctx->rx.prepend_size;
-       rxm->full_len -= tls_ctx->rx.overhead_size;
-       tls_advance_record_sn(sk, &tls_ctx->rx);
-       ctx->decrypted = true;
-       ctx->saved_data_ready(sk);
-
        return err;
 }
 
@@ -1609,6 +1608,25 @@ int tls_sw_recvmsg(struct sock *sk,
 
                rxm = strp_msg(skb);
 
+               to_decrypt = rxm->full_len - tls_ctx->rx.overhead_size;
+
+               if (to_decrypt <= len && !is_kvec && !is_peek &&
+                   ctx->control == TLS_RECORD_TYPE_DATA)
+                       zc = true;
+
+               err = decrypt_skb_update(sk, skb, &msg->msg_iter,
+                                        &chunk, &zc, ctx->async_capable);
+               if (err < 0 && err != -EINPROGRESS) {
+                       tls_err_abort(sk, EBADMSG);
+                       goto recv_end;
+               }
+
+               if (err == -EINPROGRESS) {
+                       async = true;
+                       num_async++;
+                       goto pick_next_record;
+               }
+
                if (!cmsg) {
                        int cerr;
 
@@ -1626,40 +1644,22 @@ int tls_sw_recvmsg(struct sock *sk,
                        goto recv_end;
                }
 
-               to_decrypt = rxm->full_len - tls_ctx->rx.overhead_size;
-
-               if (to_decrypt <= len && !is_kvec && !is_peek)
-                       zc = true;
-
-               err = decrypt_skb_update(sk, skb, &msg->msg_iter,
-                                        &chunk, &zc, ctx->async_capable);
-               if (err < 0 && err != -EINPROGRESS) {
-                       tls_err_abort(sk, EBADMSG);
-                       goto recv_end;
-               }
-
-               if (err == -EINPROGRESS) {
-                       async = true;
-                       num_async++;
-                       goto pick_next_record;
-               } else {
-                       if (!zc) {
-                               if (rxm->full_len > len) {
-                                       retain_skb = true;
-                                       chunk = len;
-                               } else {
-                                       chunk = rxm->full_len;
-                               }
+               if (!zc) {
+                       if (rxm->full_len > len) {
+                               retain_skb = true;
+                               chunk = len;
+                       } else {
+                               chunk = rxm->full_len;
+                       }
 
-                               err = skb_copy_datagram_msg(skb, rxm->offset,
-                                                           msg, chunk);
-                               if (err < 0)
-                                       goto recv_end;
+                       err = skb_copy_datagram_msg(skb, rxm->offset,
+                                                   msg, chunk);
+                       if (err < 0)
+                               goto recv_end;
 
-                               if (!is_peek) {
-                                       rxm->offset = rxm->offset + chunk;
-                                       rxm->full_len = rxm->full_len - chunk;
-                               }
+                       if (!is_peek) {
+                               rxm->offset = rxm->offset + chunk;
+                               rxm->full_len = rxm->full_len - chunk;
                        }
                }
 
@@ -1759,15 +1759,15 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
        if (!skb)
                goto splice_read_end;
 
-       /* splice does not support reading control messages */
-       if (ctx->control != TLS_RECORD_TYPE_DATA) {
-               err = -ENOTSUPP;
-               goto splice_read_end;
-       }
-
        if (!ctx->decrypted) {
                err = decrypt_skb_update(sk, skb, NULL, &chunk, &zc, false);
 
+               /* splice does not support reading control messages */
+               if (ctx->control != TLS_RECORD_TYPE_DATA) {
+                       err = -ENOTSUPP;
+                       goto splice_read_end;
+               }
+
                if (err < 0) {
                        tls_err_abort(sk, EBADMSG);
                        goto splice_read_end;