[PATCH 3/3] net/tls: implement ->read_sock()

[Hannes Reinecke <hare@suse.de>]

Implement ->read_sock() function for use with nvme-tcp.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Boris Pismenny <boris.pismenny@gmail.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
---
 net/tls/tls.h      |  2 ++
 net/tls/tls_main.c |  2 ++
 net/tls/tls_sw.c   | 71 ++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 75 insertions(+)

diff --git a/net/tls/tls.h b/net/tls/tls.h
index 804c3880d028..a5bf3a9ce142 100644
--- a/net/tls/tls.h
+++ b/net/tls/tls.h
@@ -113,6 +113,8 @@ bool tls_sw_sock_is_readable(struct sock *sk);
 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
 			   struct pipe_inode_info *pipe,
 			   size_t len, unsigned int flags);
+int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc,
+		     sk_read_actor_t read_actor);
 
 int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
 int tls_device_sendpage(struct sock *sk, struct page *page,
diff --git a/net/tls/tls_main.c b/net/tls/tls_main.c
index f2e7302a4d96..767297a029b9 100644
--- a/net/tls/tls_main.c
+++ b/net/tls/tls_main.c
@@ -922,9 +922,11 @@ static void build_proto_ops(struct proto_ops ops[TLS_NUM_CONFIG][TLS_NUM_CONFIG]
 
 	ops[TLS_BASE][TLS_SW  ] = ops[TLS_BASE][TLS_BASE];
 	ops[TLS_BASE][TLS_SW  ].splice_read	= tls_sw_splice_read;
+	ops[TLS_BASE][TLS_SW  ].read_sock	= tls_sw_read_sock;
 
 	ops[TLS_SW  ][TLS_SW  ] = ops[TLS_SW  ][TLS_BASE];
 	ops[TLS_SW  ][TLS_SW  ].splice_read	= tls_sw_splice_read;
+	ops[TLS_SW  ][TLS_SW  ].read_sock	= tls_sw_read_sock;
 
 #ifdef CONFIG_TLS_DEVICE
 	ops[TLS_HW  ][TLS_BASE] = ops[TLS_BASE][TLS_BASE];
diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index be8e0459d403..9bee2dcd55bf 100644
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -2219,6 +2219,77 @@ ssize_t tls_sw_splice_read(struct socket *sock,  loff_t *ppos,
 	goto splice_read_end;
 }
 
+int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc,
+		     sk_read_actor_t read_actor)
+{
+	struct tls_context *tls_ctx = tls_get_ctx(sk);
+	struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx);
+	struct strp_msg *rxm = NULL;
+	struct tls_msg *tlm;
+	struct sk_buff *skb;
+	ssize_t copied = 0;
+	int err, used;
+
+	if (!skb_queue_empty(&ctx->rx_list)) {
+		skb = __skb_dequeue(&ctx->rx_list);
+	} else {
+		struct tls_decrypt_arg darg;
+
+		err = tls_rx_rec_wait(sk, NULL, true, true);
+		if (err <= 0)
+			return err;
+
+		memset(&darg.inargs, 0, sizeof(darg.inargs));
+
+		err = tls_rx_one_record(sk, NULL, &darg);
+		if (err < 0) {
+			tls_err_abort(sk, -EBADMSG);
+			return err;
+		}
+
+		tls_rx_rec_done(ctx);
+		skb = darg.skb;
+	}
+
+	do {
+		rxm = strp_msg(skb);
+		tlm = tls_msg(skb);
+
+		/* read_sock does not support reading control messages */
+		if (tlm->control != TLS_RECORD_TYPE_DATA) {
+			err = -EINVAL;
+			goto read_sock_requeue;
+		}
+
+		used = read_actor(desc, skb, rxm->offset, rxm->full_len);
+		if (used <= 0) {
+			err = used;
+			goto read_sock_end;
+		}
+
+		copied += used;
+		if (used < rxm->full_len) {
+			rxm->offset += used;
+			rxm->full_len -= used;
+			if (!desc->count)
+				goto read_sock_requeue;
+		} else {
+			consume_skb(skb);
+			if (desc->count && !skb_queue_empty(&ctx->rx_list))
+				skb = __skb_dequeue(&ctx->rx_list);
+			else
+				skb = NULL;
+		}
+	} while (skb);
+
+read_sock_end:
+	return copied ? : err;
+
+read_sock_requeue:
+	__skb_queue_head(&ctx->rx_list, skb);
+	goto read_sock_end;
+}
+
 bool tls_sw_sock_is_readable(struct sock *sk)
 {
 	struct tls_context *tls_ctx = tls_get_ctx(sk);
-- 
2.35.3