xfrmi.c

/* SPDX-License-Identifier: LGPL-2.1-only */
/*
 * Copyright (c) 2019 Eyal Birger <eyal.birger@gmail.com>
 *
 * Based on lib/route/link/ipvti.c
 */
 
/**
 * @ingroup link
 * @defgroup xfrmi XFRMI
 * xfrmi link module
 *
 * @details
 * \b Link Type Name: "xfrmi"
 *
 * @route_doc{link_xfrmi, XFRMI 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/route/link/xfrmi.h>
#include <netlink-private/route/link/api.h>
 
#define XFRMI_ATTR_LINK  (1 << 0)
#define XFRMI_ATTR_IF_ID (1 << 1)
 
#define XFRMI_LINK_TYPE_NAME "xfrm"
 
struct xfrmi_info {
        uint32_t link;
        uint32_t if_id;
        uint32_t xfrmi_mask;
};
 
static  struct nla_policy xfrmi_policy[IFLA_XFRM_MAX + 1] = {
        [IFLA_XFRM_LINK]  = { .type = NLA_U32 },
        [IFLA_XFRM_IF_ID] = { .type = NLA_U32 },
};
 
static int xfrmi_alloc(struct rtnl_link *link)
{
        struct xfrmi_info *xfrmi;
 
        if (link->l_info)
                memset(link->l_info, 0, sizeof(*xfrmi));
        else {
                xfrmi = calloc(1, sizeof(*xfrmi));
                if (!xfrmi)
                        return -NLE_NOMEM;
 
                link->l_info = xfrmi;
        }
 
        return 0;
}
 
static int xfrmi_parse(struct rtnl_link *link, struct nlattr *data,
                       struct nlattr *xstats)
{
        struct nlattr *tb[IFLA_XFRM_MAX + 1];
        struct xfrmi_info *xfrmi;
        int err;
 
        NL_DBG(3, "Parsing XFRMI link info\n");
 
        err = nla_parse_nested(tb, IFLA_XFRM_MAX, data, xfrmi_policy);
        if (err < 0)
                return err;
 
        err = xfrmi_alloc(link);
        if (err < 0)
                return err;
 
        xfrmi = link->l_info;
 
        if (tb[IFLA_XFRM_LINK]) {
                xfrmi->link = nla_get_u32(tb[IFLA_XFRM_LINK]);
                xfrmi->xfrmi_mask |= XFRMI_ATTR_LINK;
        }
 
        if (tb[IFLA_XFRM_IF_ID]) {
                xfrmi->if_id = nla_get_u32(tb[IFLA_XFRM_IF_ID]);
                xfrmi->xfrmi_mask |= XFRMI_ATTR_IF_ID;
        }
 
        return 0;
}
 
static int xfrmi_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
{
        struct xfrmi_info *xfrmi = link->l_info;
        struct nlattr *data;
 
        data = nla_nest_start(msg, IFLA_INFO_DATA);
        if (!data)
                return -NLE_MSGSIZE;
 
        if (xfrmi->xfrmi_mask & XFRMI_ATTR_LINK)
                NLA_PUT_U32(msg, IFLA_XFRM_LINK, xfrmi->link);
 
        if (xfrmi->xfrmi_mask & XFRMI_ATTR_IF_ID)
                NLA_PUT_U32(msg, IFLA_XFRM_IF_ID, xfrmi->if_id);
 
        nla_nest_end(msg, data);
 
nla_put_failure:
        return 0;
}
 
static void xfrmi_free(struct rtnl_link *link)
{
        struct xfrmi_info *xfrmi = link->l_info;
 
        free(xfrmi);
        link->l_info = NULL;
}
 
static void xfrmi_dump_line(struct rtnl_link *link, struct nl_dump_params *p)
{
        nl_dump(p, "xfrmi : %s", link->l_name);
}
 
static void xfrmi_dump_details(struct rtnl_link *link, struct nl_dump_params *p)
{
        struct xfrmi_info *xfrmi = link->l_info;
 
        if (xfrmi->xfrmi_mask & XFRMI_ATTR_LINK) {
                struct rtnl_link *parent;
                char *name;
 
                nl_dump(p, "      link ");
 
                name = NULL;
                parent = link_lookup(link->ce_cache, xfrmi->link);
                if (parent)
                        name = rtnl_link_get_name(parent);
 
                if (name)
                        nl_dump_line(p, "%s\n", name);
                else
                        nl_dump_line(p, "%u\n", xfrmi->link);
        }
 
        if (xfrmi->xfrmi_mask & XFRMI_ATTR_IF_ID) {
                nl_dump(p, "      if_id   ");
                nl_dump_line(p, "%x\n", xfrmi->if_id);
        }
}
 
static int xfrmi_clone(struct rtnl_link *dst, struct rtnl_link *src)
{
        struct xfrmi_info *xfrmi_dst, *xfrmi_src = src->l_info;
        int err;
 
        dst->l_info = NULL;
 
        err = rtnl_link_set_type(dst, XFRMI_LINK_TYPE_NAME);
        if (err < 0)
                return err;
 
        xfrmi_dst = dst->l_info;
 
        if (!xfrmi_dst || !xfrmi_src)
                BUG();
 
        memcpy(xfrmi_dst, xfrmi_src, sizeof(struct xfrmi_info));
 
        return 0;
}
 
static struct rtnl_link_info_ops xfrmi_info_ops = {
        .io_name                = XFRMI_LINK_TYPE_NAME,
        .io_alloc               = xfrmi_alloc,
        .io_parse               = xfrmi_parse,
        .io_dump = {
                [NL_DUMP_LINE]  = xfrmi_dump_line,
                [NL_DUMP_DETAILS] = xfrmi_dump_details,
        },
        .io_clone               = xfrmi_clone,
        .io_put_attrs           = xfrmi_put_attrs,
        .io_free                = xfrmi_free,
};
 
#define IS_XFRMI_LINK_ASSERT(link) do { \
                if ((link)->l_info_ops != &xfrmi_info_ops) { \
                        APPBUG("Link is not a xfrmi link. set type \"xfrmi\" first."); \
                        return -NLE_OPNOTSUPP; \
                } \
        } while(0)
 
struct rtnl_link *rtnl_link_xfrmi_alloc(void)
{
        struct rtnl_link *link;
        int err;
 
        link = rtnl_link_alloc();
        if (!link)
                return NULL;
 
        err = rtnl_link_set_type(link, XFRMI_LINK_TYPE_NAME);
        if (err < 0) {
                rtnl_link_put(link);
                return NULL;
        }
 
        return link;
}
 
/**
 * Check if link is a XFRMI link
 * @arg link            Link object
 *
 * @return True if link is a IXFRMI link, otherwise 0 is returned.
 */
int rtnl_link_is_xfrmi(struct rtnl_link *link)
{
        return link->l_info_ops && !strcmp(link->l_info_ops->io_name,
                                           XFRMI_LINK_TYPE_NAME);
}
 
/**
 * Set XFRMI link interface index
 * @arg link            Link object
 * @arg index           interface index
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_xfrmi_set_link(struct rtnl_link *link, uint32_t index)
{
        struct xfrmi_info *xfrmi = link->l_info;
 
        IS_XFRMI_LINK_ASSERT(link);
 
        xfrmi->link = index;
        xfrmi->xfrmi_mask |= XFRMI_ATTR_LINK;
 
        return 0;
}
 
/**
 * Get XFRMI link interface index
 * @arg link            Link object
 * @arg out_link        The output value on success
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_xfrmi_get_link(struct rtnl_link *link, uint32_t *out_link)
{
        struct xfrmi_info *xfrmi = link->l_info;
 
        IS_XFRMI_LINK_ASSERT(link);
 
        if (!(xfrmi->xfrmi_mask & XFRMI_ATTR_LINK))
                return -NLE_NOATTR;
 
        *out_link = xfrmi->link;
        return 0;
}
 
/**
 * Set XFRMI if_id
 * @arg link            Link object
 * @arg if_id            xfrm if_id
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_xfrmi_set_if_id(struct rtnl_link *link, uint32_t if_id)
{
        struct xfrmi_info *xfrmi = link->l_info;
 
        IS_XFRMI_LINK_ASSERT(link);
 
        xfrmi->if_id = if_id;
        xfrmi->xfrmi_mask |= XFRMI_ATTR_IF_ID;
 
        return 0;
}
 
/**
 * Get XFRMI if_id
 * @arg link            Link object
 * @arg out_if_id       The output value on success
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_xfrmi_get_if_id(struct rtnl_link *link, uint32_t *out_if_id)
{
        struct xfrmi_info *xfrmi = link->l_info;
 
        IS_XFRMI_LINK_ASSERT(link);
 
        if (!(xfrmi->xfrmi_mask & XFRMI_ATTR_IF_ID))
                return -NLE_NOATTR;
 
        *out_if_id = xfrmi->if_id;
        return 0;
}
 
static void __init xfrmi_init(void)
{
        rtnl_link_register_info(&xfrmi_info_ops);
}
 
static void __exit xfrmi_exit(void)
{
        rtnl_link_unregister_info(&xfrmi_info_ops);
}