lib/route/link/vlan.c

/* SPDX-License-Identifier: LGPL-2.1-only */
/*
 * Copyright (c) 2003-2013 Thomas Graf <tgraf@suug.ch>
 */

/**
 * @ingroup link
 * @defgroup vlan VLAN
 * Virtual LAN link module
 *
 * @details
 * \b Link Type Name: "vlan"
 *
 * @route_doc{link_vlan, VLAN Documentation}
 *
 * @{
 */

#include "nl-default.h"

#include <linux/if_vlan.h>

#include <netlink/netlink.h>
#include <netlink/attr.h>
#include <netlink/utils.h>
#include <netlink/object.h>
#include <netlink/route/rtnl.h>
#include <netlink/route/link/vlan.h>

#include "nl-route.h"
#include "link-api.h"

/** @cond SKIP */
#define VLAN_HAS_ID		(1<<0)
#define VLAN_HAS_FLAGS		(1<<1)
#define VLAN_HAS_INGRESS_QOS	(1<<2)
#define VLAN_HAS_EGRESS_QOS	(1<<3)
#define VLAN_HAS_PROTOCOL	(1<<4)

struct vlan_info
{
	uint16_t		vi_vlan_id;
	uint16_t		vi_protocol;
	unsigned int            vi_ingress_qos_mask:(VLAN_PRIO_MAX+1);
	uint32_t		vi_flags;
	uint32_t		vi_flags_mask;
	uint32_t		vi_ingress_qos[VLAN_PRIO_MAX+1];
	uint32_t		vi_negress;
	uint32_t		vi_egress_size;
	struct vlan_map * 	vi_egress_qos;
	uint32_t		vi_mask;
};

/** @endcond */

static struct nla_policy vlan_policy[IFLA_VLAN_MAX+1] = {
	[IFLA_VLAN_ID]		= { .type = NLA_U16 },
	[IFLA_VLAN_FLAGS]	= { .minlen = sizeof(struct ifla_vlan_flags) },
	[IFLA_VLAN_INGRESS_QOS]	= { .type = NLA_NESTED },
	[IFLA_VLAN_EGRESS_QOS]	= { .type = NLA_NESTED },
	[IFLA_VLAN_PROTOCOL]	= { .type = NLA_U16 },
};

static int vlan_alloc(struct rtnl_link *link)
{
	struct vlan_info *vi;

	if (link->l_info) {
		vi = link->l_info;
		free(vi->vi_egress_qos);
		memset(link->l_info, 0, sizeof(*vi));
	} else {
		if ((vi = calloc(1, sizeof(*vi))) == NULL)
			return -NLE_NOMEM;

		link->l_info = vi;
	}

	return 0;
}

static int vlan_parse(struct rtnl_link *link, struct nlattr *data,
		      struct nlattr *xstats)
{
	struct nlattr *tb[IFLA_VLAN_MAX+1];
	struct vlan_info *vi;
	int err;

	NL_DBG(3, "Parsing VLAN link info\n");

	if ((err = nla_parse_nested(tb, IFLA_VLAN_MAX, data, vlan_policy)) < 0)
		goto errout;

	if ((err = vlan_alloc(link)) < 0)
		goto errout;

	vi = link->l_info;

	if (tb[IFLA_VLAN_ID]) {
		vi->vi_vlan_id = nla_get_u16(tb[IFLA_VLAN_ID]);
		vi->vi_mask |= VLAN_HAS_ID;
	}

	if (tb[IFLA_VLAN_PROTOCOL]) {
		vi->vi_protocol = nla_get_u16(tb[IFLA_VLAN_PROTOCOL]);
		vi->vi_mask |= VLAN_HAS_PROTOCOL;
	}

	if (tb[IFLA_VLAN_FLAGS]) {
		struct ifla_vlan_flags flags;
		nla_memcpy(&flags, tb[IFLA_VLAN_FLAGS], sizeof(flags));

		vi->vi_flags = flags.flags;
		vi->vi_mask |= VLAN_HAS_FLAGS;
	}

	if (tb[IFLA_VLAN_INGRESS_QOS]) {
		struct ifla_vlan_qos_mapping *map;
		struct nlattr *nla;
		int remaining;

		vi->vi_ingress_qos_mask = 0;
		memset(vi->vi_ingress_qos, 0, sizeof(vi->vi_ingress_qos));

		nla_for_each_nested(nla, tb[IFLA_VLAN_INGRESS_QOS], remaining) {
			if (nla_len(nla) < sizeof(*map))
				return -NLE_INVAL;

			map = nla_data(nla);
			if (map->from > VLAN_PRIO_MAX) {
				return -NLE_INVAL;
			}

			/* Kernel will not explicitly serialize mappings with "to" zero
			 * (although they are implicitly set).
			 *
			 * Thus we only mark those as "set" which are explicitly sent.
			 * That is similar to what we do with the egress map and it preserves
			 * previous behavior before NL_CAPABILITY_RTNL_LINK_VLAN_INGRESS_MAP_CLEAR.
			 *
			 * It matters only when a received object is send back to kernel to modify
			 * the link.
			 */
			vi->vi_ingress_qos_mask |= (1 << map->from);
			vi->vi_ingress_qos[map->from] = map->to;
		}

		vi->vi_mask |= VLAN_HAS_INGRESS_QOS;
	}

	if (tb[IFLA_VLAN_EGRESS_QOS]) {
		struct ifla_vlan_qos_mapping *map;
		struct nlattr *nla;
		int remaining, i = 0;

		nla_for_each_nested(nla, tb[IFLA_VLAN_EGRESS_QOS], remaining) {
			if (nla_len(nla) < sizeof(*map))
				return -NLE_INVAL;
			i++;
		}

		/* align to have a little reserve */
		vi->vi_egress_size = (i + 32) & ~31;
		vi->vi_egress_qos = calloc(vi->vi_egress_size, sizeof(*vi->vi_egress_qos));
		if (vi->vi_egress_qos == NULL)
			return -NLE_NOMEM;

		i = 0;
		nla_for_each_nested(nla, tb[IFLA_VLAN_EGRESS_QOS], remaining) {
			map = nla_data(nla);
			NL_DBG(4, "Assigning egress qos mapping %d\n", i);
			vi->vi_egress_qos[i].vm_from = map->from;
			vi->vi_egress_qos[i++].vm_to = map->to;
		}

		vi->vi_negress = i;
		vi->vi_mask |= VLAN_HAS_EGRESS_QOS;
	}

	err = 0;
errout:
	return err;
}

static void vlan_free(struct rtnl_link *link)
{
	struct vlan_info *vi = link->l_info;

	if (vi) {
		free(vi->vi_egress_qos);
		vi->vi_egress_qos = NULL;
	}

	free(vi);
	link->l_info = NULL;
}

static void vlan_dump_line(struct rtnl_link *link, struct nl_dump_params *p)
{
	struct vlan_info *vi = link->l_info;

	nl_dump(p, "vlan-id %d", vi->vi_vlan_id);
}

static void vlan_dump_details(struct rtnl_link *link, struct nl_dump_params *p)
{
	struct vlan_info *vi = link->l_info;
	int printed;
	uint32_t i;
	char buf[64];

	rtnl_link_vlan_flags2str(vi->vi_flags, buf, sizeof(buf));
	nl_dump_line(p, "    vlan-info id %d <%s>", vi->vi_vlan_id, buf);

	if (vi->vi_mask & VLAN_HAS_PROTOCOL)
		nl_dump_line(p, "    vlan protocol <%d>", ntohs(vi->vi_protocol));

	nl_dump(p, "\n");

	if (vi->vi_mask & VLAN_HAS_INGRESS_QOS) {
		nl_dump_line(p, 
		"      ingress vlan prio -> qos/socket prio mapping:\n");
		for (i = 0, printed = 0; i <= VLAN_PRIO_MAX; i++) {
			if (vi->vi_ingress_qos_mask & (1 << i)) {
				if (printed == 0)
					nl_dump_line(p, "      ");
				nl_dump(p, "%x -> %#08x, ",
					i, vi->vi_ingress_qos[i]);
				if (printed++ == 3) {
					nl_dump(p, "\n");
					printed = 0;
				}
			}
		}

		if (printed > 0 && printed != 4)
			nl_dump(p, "\n");
	}

	if (vi->vi_mask & VLAN_HAS_EGRESS_QOS) {
		nl_dump_line(p, 
		"      egress qos/socket prio -> vlan prio mapping:\n");
		for (i = 0, printed = 0; i < vi->vi_negress; i++) {
			if (printed == 0)
				nl_dump_line(p, "      ");
			nl_dump(p, "%#08x -> %x, ",
				vi->vi_egress_qos[i].vm_from,
				vi->vi_egress_qos[i].vm_to);
			if (printed++ == 3) {
				nl_dump(p, "\n");
				printed = 0;
			}
		}

		if (printed > 0 && printed != 4)
			nl_dump(p, "\n");
	}
}

static int vlan_clone(struct rtnl_link *dst, struct rtnl_link *src)
{
	struct vlan_info *vdst, *vsrc = src->l_info;
	int err;
	struct vlan_map *p = NULL;

	dst->l_info = NULL;
	if ((err = rtnl_link_set_type(dst, "vlan")) < 0)
		return err;
	vdst = dst->l_info;

	if (vsrc->vi_negress) {
		p = calloc(vsrc->vi_negress,
		           sizeof(struct vlan_map));
		if (!p)
			return -NLE_NOMEM;
	}

	*vdst = *vsrc;

	if (vsrc->vi_negress) {
		vdst->vi_egress_size = vsrc->vi_negress;
		vdst->vi_egress_qos = p;
		memcpy(vdst->vi_egress_qos, vsrc->vi_egress_qos,
		       vsrc->vi_negress * sizeof(struct vlan_map));
	}

	return 0;
}

static int vlan_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
{
	struct vlan_info *vi = link->l_info;
	struct nlattr *data;
	int nest_count = 0;

	if (!(data = nla_nest_start(msg, IFLA_INFO_DATA)))
		goto nla_put_failure;

	nest_count++;

	if (vi->vi_mask & VLAN_HAS_ID)
		NLA_PUT_U16(msg, IFLA_VLAN_ID, vi->vi_vlan_id);

	if (vi->vi_mask & VLAN_HAS_PROTOCOL)
		NLA_PUT_U16(msg, IFLA_VLAN_PROTOCOL, vi->vi_protocol);

	if (vi->vi_mask & VLAN_HAS_FLAGS) {
		struct ifla_vlan_flags flags = {
			.flags = vi->vi_flags,
			.mask = vi->vi_flags_mask,
		};

		NLA_PUT(msg, IFLA_VLAN_FLAGS, sizeof(flags), &flags);
	}

	if (vi->vi_mask & VLAN_HAS_INGRESS_QOS) {
		struct ifla_vlan_qos_mapping map;
		struct nlattr *qos;
		int i;

		if (!(qos = nla_nest_start(msg, IFLA_VLAN_INGRESS_QOS)))
			goto nla_put_failure;

		nest_count++;

		for (i = 0; i <= VLAN_PRIO_MAX; i++) {
			if (vi->vi_ingress_qos_mask & (1 << i)) {
				map.from = i;
				map.to = vi->vi_ingress_qos[i];

				NLA_PUT(msg, i, sizeof(map), &map);
			}
		}

		nla_nest_end(msg, qos);
		nest_count--;
	}

	if (vi->vi_mask & VLAN_HAS_EGRESS_QOS) {
		struct ifla_vlan_qos_mapping map;
		struct nlattr *qos;
		uint32_t i;

		if (!(qos = nla_nest_start(msg, IFLA_VLAN_EGRESS_QOS)))
			goto nla_put_failure;

		nest_count++;

		for (i = 0; i < vi->vi_negress; i++) {
			map.from = vi->vi_egress_qos[i].vm_from;
			map.to = vi->vi_egress_qos[i].vm_to;

			NLA_PUT(msg, i, sizeof(map), &map);
		}

		nla_nest_end(msg, qos);
		nest_count--;
	}

	nla_nest_end(msg, data);
	return 0;

nla_put_failure:
	for (; nest_count > 0; nest_count--)
		nla_nest_cancel(msg, data);
	return -NLE_MSGSIZE;
}

static struct rtnl_link_info_ops vlan_info_ops = {
	.io_name		= "vlan",
	.io_alloc		= vlan_alloc,
	.io_parse		= vlan_parse,
	.io_dump = {
	    [NL_DUMP_LINE]	= vlan_dump_line,
	    [NL_DUMP_DETAILS]	= vlan_dump_details,
	},
	.io_clone		= vlan_clone,
	.io_put_attrs		= vlan_put_attrs,
	.io_free		= vlan_free,
};

/** @cond SKIP */
#define IS_VLAN_LINK_ASSERT(link) \
	if ((link)->l_info_ops != &vlan_info_ops) { \
		APPBUG("Link is not a vlan link. set type \"vlan\" first."); \
		return -NLE_OPNOTSUPP; \
	}
/** @endcond */

/**
 * @name VLAN Object
 * @{
 */

/**
 * Allocate link object of type VLAN
 *
 * @return Allocated link object or NULL.
 */
struct rtnl_link *rtnl_link_vlan_alloc(void)
{
	struct rtnl_link *link;

	if (!(link = rtnl_link_alloc()))
		return NULL;

	if (rtnl_link_set_type(link, "vlan") < 0) {
		rtnl_link_put(link);
		return NULL;
	}

	return link;
}

/**
 * Check if link is a VLAN link
 * @arg link		Link object
 *
 * @return True if link is a VLAN link, otherwise false is returned.
 */
int rtnl_link_is_vlan(struct rtnl_link *link)
{
	return link->l_info_ops && !strcmp(link->l_info_ops->io_name, "vlan");
}

/**
 * Set VLAN ID
 * @arg link		Link object
 * @arg id		VLAN identifier
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_vlan_set_id(struct rtnl_link *link, uint16_t id)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	vi->vi_vlan_id = id;
	vi->vi_mask |= VLAN_HAS_ID;

	return 0;
}

/**
 * Get VLAN Id
 * @arg link		Link object
 *
 * @return VLAN id, 0 if not set or a negative error code.
 */
int rtnl_link_vlan_get_id(struct rtnl_link *link)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	if (vi->vi_mask & VLAN_HAS_ID)
		return vi->vi_vlan_id;
	else
		return 0;
}

/**
 * Set VLAN protocol
 * @arg link		Link object
 * @arg protocol	VLAN protocol in network byte order.
 *   Probably you want to set it to something like htons(ETH_P_8021Q).
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_vlan_set_protocol(struct rtnl_link *link, uint16_t protocol)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	vi->vi_protocol = protocol;
	vi->vi_mask |= VLAN_HAS_PROTOCOL;

	return 0;
}

/**
 * Get VLAN protocol
 * @arg link		Link object
 *
 * @return VLAN protocol in network byte order like htons(ETH_P_8021Q),
 *   0 if not set or a negative error code.
 */
int rtnl_link_vlan_get_protocol(struct rtnl_link *link)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	if (vi->vi_mask & VLAN_HAS_PROTOCOL)
		return vi->vi_protocol;
	else
		return 0;
}

/**
 * Set VLAN flags
 * @arg link		Link object
 * @arg flags		VLAN flags
 *
 * @return 0 on success or a negative error code.
 */
int rtnl_link_vlan_set_flags(struct rtnl_link *link, unsigned int flags)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	vi->vi_flags_mask |= flags;
	vi->vi_flags |= flags;
	vi->vi_mask |= VLAN_HAS_FLAGS;

	return 0;
}

/**
 * Unset VLAN flags
 * @arg link		Link object
 * @arg flags		VLAN flags
 *
 * @return 0 on success or a negative error code.
 */
int rtnl_link_vlan_unset_flags(struct rtnl_link *link, unsigned int flags)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	vi->vi_flags_mask |= flags;
	vi->vi_flags &= ~flags;
	vi->vi_mask |= VLAN_HAS_FLAGS;

	return 0;
}

/**
 * Get VLAN flags
 * @arg link		Link object
 *
 * @return VLAN flags, 0 if none set, or a negative error code.
 */
int rtnl_link_vlan_get_flags(struct rtnl_link *link)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	return vi->vi_flags;
}

/** @} */

/**
 * @name Quality of Service
 * @{
 */

int rtnl_link_vlan_set_ingress_map(struct rtnl_link *link, int from,
				   uint32_t to)
{
	struct vlan_info *vi = link->l_info;

	IS_VLAN_LINK_ASSERT(link);

	if (from < 0 || from > VLAN_PRIO_MAX)
		return -NLE_INVAL;

	vi->vi_ingress_qos_mask |= (1 << from);
	vi->vi_ingress_qos[from] = to;
	vi->vi_mask |= VLAN_HAS_INGRESS_QOS;

	return 0;
}

uint32_t *rtnl_link_vlan_get_ingress_map(struct rtnl_link *link)
{
	struct vlan_info *vi = link->l_info;

	if (link->l_info_ops != &vlan_info_ops || !link->l_info_ops)
		return NULL;

	if (vi->vi_mask & VLAN_HAS_INGRESS_QOS)
		return vi->vi_ingress_qos;
	else
		return NULL;
}

int rtnl_link_vlan_set_egress_map(struct rtnl_link *link, uint32_t from, int to)
{
	struct vlan_info *vi = link->l_info;

	if (link->l_info_ops != &vlan_info_ops || !link->l_info_ops)
		return -NLE_OPNOTSUPP;

	if (to < 0 || to > VLAN_PRIO_MAX)
		return -NLE_INVAL;

	if (vi->vi_negress >= vi->vi_egress_size) {
		uint32_t new_size = vi->vi_egress_size + 1 + vi->vi_egress_size / 2;
		size_t bytes;
		void *ptr;

		if (new_size < vi->vi_egress_size)
			return -NLE_NOMEM;
		bytes = (size_t) new_size * sizeof(struct vlan_map);
		if (bytes / sizeof (struct vlan_map) != new_size)
			return -NLE_NOMEM;
		ptr = realloc(vi->vi_egress_qos, bytes);
		if (!ptr)
			return -NLE_NOMEM;

		vi->vi_egress_qos = ptr;
		vi->vi_egress_size = new_size;
	}

	vi->vi_egress_qos[vi->vi_negress].vm_from = from;
	vi->vi_egress_qos[vi->vi_negress].vm_to = to;
	vi->vi_negress++;
	vi->vi_mask |= VLAN_HAS_EGRESS_QOS;

	return 0;
}

struct vlan_map *rtnl_link_vlan_get_egress_map(struct rtnl_link *link,
					       int *negress)
{
	struct vlan_info *vi = link->l_info;

	if (link->l_info_ops != &vlan_info_ops || !link->l_info_ops)
		return NULL;

	if (negress == NULL)
		return NULL;

	if (vi->vi_mask & VLAN_HAS_EGRESS_QOS) {
		*negress = vi->vi_negress;
		return vi->vi_egress_qos;
	} else {
		*negress = 0;
		return NULL;
	}
}

/** @} */

static const struct trans_tbl vlan_flags[] = {
	__ADD(VLAN_FLAG_REORDER_HDR, reorder_hdr),
	__ADD(VLAN_FLAG_GVRP, gvrp),
	__ADD(VLAN_FLAG_LOOSE_BINDING, loose_binding),
	__ADD(VLAN_FLAG_MVRP, mvrp),
	__ADD(VLAN_FLAG_BRIDGE_BINDING, bridge_binding),
};

/**
 * @name Flag Translation
 * @{
 */

char *rtnl_link_vlan_flags2str(int flags, char *buf, size_t len)
{
	return __flags2str(flags, buf, len, vlan_flags, ARRAY_SIZE(vlan_flags));
}

int rtnl_link_vlan_str2flags(const char *name)
{
	return __str2flags(name, vlan_flags, ARRAY_SIZE(vlan_flags));
}

/** @} */


static void _nl_init vlan_init(void)
{
	rtnl_link_register_info(&vlan_info_ops);
}

static void _nl_exit vlan_exit(void)
{
	rtnl_link_unregister_info(&vlan_info_ops);
}

/** @} */