1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2019 Vincenzo Maffione <vmaffione@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
18 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
19 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
20 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
21 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
22 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
23 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
24 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
25 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * $FreeBSD$
28 */
29
30#ifndef __NET_BACKENDS_H__
31#define __NET_BACKENDS_H__
32
33#include <stdint.h>
34
35/* Opaque type representing a network backend. */
36typedef struct net_backend net_backend_t;
37
38/* Interface between network frontends and the network backends. */
39typedef void (*net_be_rxeof_t)(int, enum ev_type, void *param);
40int	netbe_init(net_backend_t **be, const char *devname, net_be_rxeof_t cb,
41            void *param);
42void	netbe_cleanup(net_backend_t *be);
43uint64_t netbe_get_cap(net_backend_t *be);
44int	 netbe_set_cap(net_backend_t *be, uint64_t cap,
45             unsigned vnet_hdr_len);
46size_t	netbe_get_vnet_hdr_len(net_backend_t *be);
47ssize_t	netbe_send(net_backend_t *be, const struct iovec *iov, int iovcnt);
48ssize_t	netbe_peek_recvlen(net_backend_t *be);
49ssize_t	netbe_recv(net_backend_t *be, const struct iovec *iov, int iovcnt);
50ssize_t	netbe_rx_discard(net_backend_t *be);
51void	netbe_rx_disable(net_backend_t *be);
52void	netbe_rx_enable(net_backend_t *be);
53
54
55/*
56 * Network device capabilities taken from the VirtIO standard.
57 * Despite the name, these capabilities can be used by different frontents
58 * (virtio-net, ptnet) and supported by different backends (netmap, tap, ...).
59 */
60#define	VIRTIO_NET_F_CSUM	(1 <<  0) /* host handles partial cksum */
61#define	VIRTIO_NET_F_GUEST_CSUM	(1 <<  1) /* guest handles partial cksum */
62#define	VIRTIO_NET_F_MAC	(1 <<  5) /* host supplies MAC */
63#define	VIRTIO_NET_F_GSO_DEPREC	(1 <<  6) /* deprecated: host handles GSO */
64#define	VIRTIO_NET_F_GUEST_TSO4	(1 <<  7) /* guest can rcv TSOv4 */
65#define	VIRTIO_NET_F_GUEST_TSO6	(1 <<  8) /* guest can rcv TSOv6 */
66#define	VIRTIO_NET_F_GUEST_ECN	(1 <<  9) /* guest can rcv TSO with ECN */
67#define	VIRTIO_NET_F_GUEST_UFO	(1 << 10) /* guest can rcv UFO */
68#define	VIRTIO_NET_F_HOST_TSO4	(1 << 11) /* host can rcv TSOv4 */
69#define	VIRTIO_NET_F_HOST_TSO6	(1 << 12) /* host can rcv TSOv6 */
70#define	VIRTIO_NET_F_HOST_ECN	(1 << 13) /* host can rcv TSO with ECN */
71#define	VIRTIO_NET_F_HOST_UFO	(1 << 14) /* host can rcv UFO */
72#define	VIRTIO_NET_F_MRG_RXBUF	(1 << 15) /* host can merge RX buffers */
73#define	VIRTIO_NET_F_STATUS	(1 << 16) /* config status field available */
74#define	VIRTIO_NET_F_CTRL_VQ	(1 << 17) /* control channel available */
75#define	VIRTIO_NET_F_CTRL_RX	(1 << 18) /* control channel RX mode support */
76#define	VIRTIO_NET_F_CTRL_VLAN	(1 << 19) /* control channel VLAN filtering */
77#define	VIRTIO_NET_F_GUEST_ANNOUNCE \
78				(1 << 21) /* guest can send gratuitous pkts */
79
80/*
81 * Fixed network header size
82 */
83struct virtio_net_rxhdr {
84	uint8_t		vrh_flags;
85	uint8_t		vrh_gso_type;
86	uint16_t	vrh_hdr_len;
87	uint16_t	vrh_gso_size;
88	uint16_t	vrh_csum_start;
89	uint16_t	vrh_csum_offset;
90	uint16_t	vrh_bufs;
91} __packed;
92
93#endif /* __NET_BACKENDS_H__ */
94