route/vrf: add VRF support

http://lists.infradead.org/pipermail/libnl/2015-October/001991.html

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
[thaller@redhat.com: slightly modified original patch]
Signed-off-by: Thomas Haller <thaller@redhat.com>

1 files changed, 263 insertions, 0 deletions

diff --git a/lib/route/link/vrf.c b/lib/route/link/vrf.c
new file mode 100644
index 0000000..84d2d8b
--- /dev/null
+++ b/lib/route/link/vrf.c
@@ -0,0 +1,263 @@
+/*
+ * lib/route/link/vrf.c      VRF Link Info
+ *
+ *     This library is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU Lesser General Public
+ *     License as published by the Free Software Foundation version 2.1
+ *     of the License.
+ *
+ * Copyright (c) 2015 Cumulus Networks. All rights reserved.
+ * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
+ */
+
+/**
+ * @ingroup link
+ * @defgroup vrf VRF
+ * Virtual Routing and Forwarding link module
+ *
+ * @details
+ * \b Link Type Name: "vrf"
+ *
+ * @route_doc{link_vrf, VRF Documentation}
+ *
+ * @{
+ */
+
+#include <netlink-private/netlink.h>
+#include <netlink/netlink.h>
+#include <netlink/attr.h>
+#include <netlink/utils.h>
+#include <netlink/object.h>
+#include <netlink/route/rtnl.h>
+#include <netlink-private/route/link/api.h>
+#include <netlink/route/link/vrf.h>
+
+#include <linux/if_link.h>
+#include <linux-private/linux/rtnetlink.h>
+
+#define VRF_TABLE_ID_MAX  RT_TABLE_MAX
+
+/** @cond SKIP */
+#define VRF_HAS_TABLE_ID    (1<<0)
+
+struct vrf_info {
+	uint32_t        table_id;
+	uint32_t        vi_mask;
+};
+
+/** @endcond */
+
+static struct nla_policy vrf_policy[IFLA_VRF_MAX + 1] = {
+	[IFLA_VRF_TABLE]         = { .type = NLA_U32 },
+};
+
+static int vrf_alloc(struct rtnl_link *link)
+{
+	struct vrf_info *vi;
+
+	if (link->l_info) {
+		memset(link->l_info, 0, sizeof (*vi));
+		return 0;
+	}
+
+	if ((vi = calloc(1, sizeof(*vi))) == NULL)
+		return -NLE_NOMEM;
+
+	link->l_info = vi;
+
+	return 0;
+}
+
+static int vrf_parse(struct rtnl_link *link, struct nlattr *data,
+		     struct nlattr *xstats)
+{
+	struct nlattr *tb[IFLA_VRF_MAX+1];
+	struct vrf_info *vi;
+	int err;
+
+	NL_DBG(3, "Parsing VRF link info");
+
+	if ((err = nla_parse_nested(tb, IFLA_VRF_MAX, data, vrf_policy)) < 0)
+		goto errout;
+
+	if ((err = vrf_alloc(link)) < 0)
+		goto errout;
+
+	vi = link->l_info;
+
+	if (tb[IFLA_VRF_TABLE]) {
+		vi->table_id = nla_get_u32(tb[IFLA_VRF_TABLE]);
+		vi->vi_mask |= VRF_HAS_TABLE_ID;
+	}
+
+	err = 0;
+
+errout:
+	return err;
+}
+
+static void vrf_free(struct rtnl_link *link)
+{
+	free(link->l_info);
+	link->l_info = NULL;
+}
+
+static int vrf_clone(struct rtnl_link *dst, struct rtnl_link *src)
+{
+	struct vrf_info *vdst, *vsrc = src->l_info;
+	int err;
+
+	if ((err = rtnl_link_set_type(dst, "vrf")) < 0)
+		return err;
+	vdst = dst->l_info;
+
+	BUG_ON(!vdst || !vsrc);
+
+	memcpy(vdst, vsrc, sizeof(struct vrf_info));
+
+	return 0;
+}
+
+static int vrf_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
+{
+	struct vrf_info *vi = link->l_info;
+	struct nlattr *data;
+
+	if (!(data = nla_nest_start(msg, IFLA_INFO_DATA)))
+		return -NLE_NOMEM;
+
+	if (vi->vi_mask & VRF_HAS_TABLE_ID) {
+		NLA_PUT_U32(msg, IFLA_VRF_TABLE, vi->table_id);
+	}
+
+	nla_nest_end(msg, data);
+
+nla_put_failure:
+
+	return 0;
+}
+
+static void vrf_dump(struct rtnl_link *link, struct nl_dump_params *p)
+{
+	struct vrf_info *vi = link->l_info;
+
+	if (vi->vi_mask & VRF_HAS_TABLE_ID) {
+		nl_dump(p, "table-id %u", vi->table_id);
+	}
+}
+
+static struct rtnl_link_info_ops vrf_info_ops = {
+	.io_name                = "vrf",
+	.io_alloc               = vrf_alloc,
+	.io_parse               = vrf_parse,
+	.io_dump = {
+		[NL_DUMP_LINE]     = vrf_dump,
+		[NL_DUMP_DETAILS]  = vrf_dump,
+	},
+	.io_clone               = vrf_clone,
+	.io_put_attrs           = vrf_put_attrs,
+	.io_free                = vrf_free,
+};
+
+/** @cond SKIP */
+#define IS_VRF_LINK_ASSERT(link) \
+	if ((link)->l_info_ops != &vrf_info_ops) { \
+		APPBUG("Link is not a VRF link. set type \"vrf\" first."); \
+		return -NLE_OPNOTSUPP; \
+	}
+/** @endcond */
+
+/**
+ * @name VRF Object
+ * @{
+ */
+
+/**
+ * Allocate link object of type VRF
+ *
+ * @return Allocated link object or NULL.
+ */
+struct rtnl_link *rtnl_link_vrf_alloc(void)
+{
+	struct rtnl_link *link;
+	int err;
+
+	if (!(link = rtnl_link_alloc()))
+		return NULL;
+
+	if ((err = rtnl_link_set_type(link, "vrf")) < 0) {
+		rtnl_link_put(link);
+		return NULL;
+	}
+
+	return link;
+}
+
+/**
+ * Check if link is a VRF link
+ * @arg link           Link object
+ *
+ * @return True if link is a VRF link, otherwise false is returned.
+ */
+int rtnl_link_is_vrf(struct rtnl_link *link)
+{
+	return link->l_info_ops && !strcmp(link->l_info_ops->io_name, "vrf");
+}
+
+/**
+ * Get VRF table id
+ * @arg link           Link object
+ * @arg id             Pointer to store table identifier
+ *
+ * @return 0 on success or a negative error code
+ */
+int rtnl_link_vrf_get_tableid(struct rtnl_link *link, uint32_t *id)
+{
+	struct vrf_info *vi = link->l_info;
+
+	IS_VRF_LINK_ASSERT(link);
+	if(!id)
+		return -NLE_INVAL;
+
+	if (vi->vi_mask & VRF_HAS_TABLE_ID)
+		*id = vi->table_id;
+	else
+		return -NLE_AGAIN;
+
+	return 0;
+}
+
+/**
+ * Set VRF table id
+ * @arg link           Link object
+ * @arg id             Table identifier associated with VRF link
+ *
+ * @return 0 on success or a negative error code
+ */
+int rtnl_link_vrf_set_tableid(struct rtnl_link *link, uint32_t id)
+{
+	struct vrf_info *vi = link->l_info;
+
+	IS_VRF_LINK_ASSERT(link);
+	if(id > VRF_TABLE_ID_MAX)
+		return -NLE_INVAL;
+
+	vi->table_id = id;
+	vi->vi_mask |= VRF_HAS_TABLE_ID;
+
+	return 0;
+}
+
+/** @} */
+
+static void __init vrf_init(void)
+{
+	rtnl_link_register_info(&vrf_info_ops);
+}
+
+static void __exit vrf_exit(void)
+{
+	rtnl_link_unregister_info(&vrf_info_ops);
+}
+
+/** @} */