ipip.c

/* SPDX-License-Identifier: LGPL-2.1-only */
/*
 * Copyright (c) 2014 Susant Sahani <susant@redhat.com>
 */
 
/**
 * @ingroup link
 * @defgroup ipip IPIP
 * ipip link module
 *
 * @details
 * \b Link Type Name: "ipip"
 *
 * @route_doc{link_ipip, IPIP 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/ipip.h>
#include <netlink-private/route/link/api.h>
#include <linux/if_tunnel.h>
 
#define IPIP_ATTR_LINK          (1 << 0)
#define IPIP_ATTR_LOCAL         (1 << 1)
#define IPIP_ATTR_REMOTE        (1 << 2)
#define IPIP_ATTR_TTL           (1 << 3)
#define IPIP_ATTR_TOS           (1 << 4)
#define IPIP_ATTR_PMTUDISC      (1 << 5)
#define IPIP_ATTR_FWMARK        (1 << 6)
 
struct ipip_info
{
        uint8_t    ttl;
        uint8_t    tos;
        uint8_t    pmtudisc;
        uint32_t   link;
        uint32_t   local;
        uint32_t   remote;
        uint32_t   fwmark;
        uint32_t   ipip_mask;
};
 
static struct nla_policy ipip_policy[IFLA_IPTUN_MAX + 1] = {
        [IFLA_IPTUN_LINK]       = { .type = NLA_U32 },
        [IFLA_IPTUN_LOCAL]      = { .type = NLA_U32 },
        [IFLA_IPTUN_REMOTE]     = { .type = NLA_U32 },
        [IFLA_IPTUN_TTL]        = { .type = NLA_U8 },
        [IFLA_IPTUN_TOS]        = { .type = NLA_U8 },
        [IFLA_IPTUN_PMTUDISC]   = { .type = NLA_U8 },
        [IFLA_IPTUN_FWMARK]     = { .type = NLA_U32 },
};
 
static int ipip_alloc(struct rtnl_link *link)
{
        struct ipip_info *ipip;
 
        if (link->l_info)
                memset(link->l_info, 0, sizeof(*ipip));
        else {
                ipip = calloc(1, sizeof(*ipip));
                if (!ipip)
                        return -NLE_NOMEM;
 
                link->l_info = ipip;
        }
 
        return 0;
}
 
static int ipip_parse(struct rtnl_link *link, struct nlattr *data,
                      struct nlattr *xstats)
{
        struct nlattr *tb[IFLA_IPTUN_MAX + 1];
        struct ipip_info *ipip;
        int err;
 
        NL_DBG(3, "Parsing IPIP link info\n");
 
        err = nla_parse_nested(tb, IFLA_IPTUN_MAX, data, ipip_policy);
        if (err < 0)
                goto errout;
 
        err = ipip_alloc(link);
        if (err < 0)
                goto errout;
 
        ipip = link->l_info;
 
        if (tb[IFLA_IPTUN_LINK]) {
                ipip->link = nla_get_u32(tb[IFLA_IPTUN_LINK]);
                ipip->ipip_mask |= IPIP_ATTR_LINK;
        }
 
        if (tb[IFLA_IPTUN_LOCAL]) {
                ipip->local = nla_get_u32(tb[IFLA_IPTUN_LOCAL]);
                ipip->ipip_mask |= IPIP_ATTR_LOCAL;
        }
 
        if (tb[IFLA_IPTUN_REMOTE]) {
                ipip->remote = nla_get_u32(tb[IFLA_IPTUN_REMOTE]);
                ipip->ipip_mask |= IPIP_ATTR_REMOTE;
        }
 
        if (tb[IFLA_IPTUN_TTL]) {
                ipip->ttl = nla_get_u8(tb[IFLA_IPTUN_TTL]);
                ipip->ipip_mask |= IPIP_ATTR_TTL;
        }
 
        if (tb[IFLA_IPTUN_TOS]) {
                ipip->tos = nla_get_u8(tb[IFLA_IPTUN_TOS]);
                ipip->ipip_mask |= IPIP_ATTR_TOS;
        }
 
        if (tb[IFLA_IPTUN_PMTUDISC]) {
                ipip->pmtudisc = nla_get_u8(tb[IFLA_IPTUN_PMTUDISC]);
                ipip->ipip_mask |= IPIP_ATTR_PMTUDISC;
        }
 
        if (tb[IFLA_IPTUN_FWMARK]) {
                ipip->fwmark = nla_get_u32(tb[IFLA_IPTUN_FWMARK]);
                ipip->ipip_mask |= IPIP_ATTR_FWMARK;
        }
 
        err = 0;
 
errout:
        return err;
}
 
static int ipip_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
        struct nlattr *data;
 
        data = nla_nest_start(msg, IFLA_INFO_DATA);
        if (!data)
                return -NLE_MSGSIZE;
 
        if (ipip->ipip_mask & IPIP_ATTR_LINK)
                NLA_PUT_U32(msg, IFLA_IPTUN_LINK, ipip->link);
 
        if (ipip->ipip_mask & IPIP_ATTR_LOCAL)
                NLA_PUT_U32(msg, IFLA_IPTUN_LOCAL, ipip->local);
 
        if (ipip->ipip_mask & IPIP_ATTR_REMOTE)
                NLA_PUT_U32(msg, IFLA_IPTUN_REMOTE, ipip->remote);
 
        if (ipip->ipip_mask & IPIP_ATTR_TTL)
                NLA_PUT_U8(msg, IFLA_IPTUN_TTL, ipip->ttl);
 
        if (ipip->ipip_mask & IPIP_ATTR_TOS)
                NLA_PUT_U8(msg, IFLA_IPTUN_TOS, ipip->tos);
 
        if (ipip->ipip_mask & IPIP_ATTR_PMTUDISC)
                NLA_PUT_U8(msg, IFLA_IPTUN_PMTUDISC, ipip->pmtudisc);
 
        if (ipip->ipip_mask & IPIP_ATTR_FWMARK)
                NLA_PUT_U32(msg, IFLA_IPTUN_FWMARK, ipip->fwmark);
 
        nla_nest_end(msg, data);
 
nla_put_failure:
        return 0;
}
 
static void ipip_free(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        free(ipip);
        link->l_info = NULL;
}
 
static void ipip_dump_line(struct rtnl_link *link, struct nl_dump_params *p)
{
        nl_dump(p, "ipip : %s", link->l_name);
}
 
static void ipip_dump_details(struct rtnl_link *link, struct nl_dump_params *p)
{
        struct ipip_info *ipip = link->l_info;
        char *name, addr[INET_ADDRSTRLEN];
        struct rtnl_link *parent;
 
        if (ipip->ipip_mask & IPIP_ATTR_LINK) {
                nl_dump(p, "      link ");
 
                name = NULL;
                parent = link_lookup(link->ce_cache, ipip->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", ipip->link);
        }
 
        if (ipip->ipip_mask & IPIP_ATTR_LOCAL) {
                nl_dump(p, "      local ");
                if(inet_ntop(AF_INET, &ipip->local, addr, sizeof(addr)))
                        nl_dump_line(p, "%s\n", addr);
                else
                        nl_dump_line(p, "%#x\n", ntohs(ipip->local));
        }
 
        if (ipip->ipip_mask & IPIP_ATTR_REMOTE) {
                nl_dump(p, "      remote ");
                if(inet_ntop(AF_INET, &ipip->remote, addr, sizeof(addr)))
                        nl_dump_line(p, "%s\n", addr);
                else
                        nl_dump_line(p, "%#x\n", ntohs(ipip->remote));
        }
 
        if (ipip->ipip_mask & IPIP_ATTR_TTL) {
                nl_dump(p, "      ttl ");
                nl_dump_line(p, "%u\n", ipip->ttl);
        }
 
        if (ipip->ipip_mask & IPIP_ATTR_TOS) {
                nl_dump(p, "      tos ");
                nl_dump_line(p, "%u\n", ipip->tos);
        }
 
        if (ipip->ipip_mask & IPIP_ATTR_PMTUDISC) {
                nl_dump(p, "      pmtudisc ");
                nl_dump_line(p, "enabled (%#x)\n", ipip->pmtudisc);
        }
 
        if (ipip->ipip_mask & IPIP_ATTR_FWMARK) {
                nl_dump(p, "      fwmark ");
                nl_dump_line(p, "%x\n", ipip->fwmark);
        }
}
 
static int ipip_clone(struct rtnl_link *dst, struct rtnl_link *src)
{
        struct ipip_info *ipip_dst, *ipip_src = src->l_info;
        int err;
 
        dst->l_info = NULL;
 
        err = rtnl_link_set_type(dst, "ipip");
        if (err < 0)
                return err;
 
        ipip_dst = dst->l_info;
 
        if (!ipip_dst || !ipip_src)
                BUG();
 
        memcpy(ipip_dst, ipip_src, sizeof(struct ipip_info));
 
        return 0;
}
 
static struct rtnl_link_info_ops ipip_info_ops = {
        .io_name                = "ipip",
        .io_alloc               = ipip_alloc,
        .io_parse               = ipip_parse,
        .io_dump = {
                [NL_DUMP_LINE]  = ipip_dump_line,
                [NL_DUMP_DETAILS] = ipip_dump_details,
        },
        .io_clone               = ipip_clone,
        .io_put_attrs           = ipip_put_attrs,
        .io_free                = ipip_free,
};
 
#define IS_IPIP_LINK_ASSERT(link)                                            \
        if ((link)->l_info_ops != &ipip_info_ops) {                          \
                APPBUG("Link is not a ipip link. set type \"ipip\" first."); \
                return -NLE_OPNOTSUPP;                                       \
        }
 
struct rtnl_link *rtnl_link_ipip_alloc(void)
{
        struct rtnl_link *link;
        int err;
 
        link = rtnl_link_alloc();
        if (!link)
                return NULL;
 
        err = rtnl_link_set_type(link, "ipip");
        if (err < 0) {
                rtnl_link_put(link);
                return NULL;
        }
 
        return link;
}
 
/**
 * Check if link is a IPIP link
 * @arg link            Link object
 *
 * @return True if link is a IPIP link, otherwise false is returned.
 */
int rtnl_link_is_ipip(struct rtnl_link *link)
{
        return link->l_info_ops && !strcmp(link->l_info_ops->io_name, "ipip");
}
 
/**
 * Create a new ipip tunnel device
 * @arg sock            netlink socket
 * @arg name            name of the tunnel deviceL
 *
 * Creates a new ipip tunnel device in the kernel
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_add(struct nl_sock *sk, const char *name)
{
        struct rtnl_link *link;
        int err;
 
        link = rtnl_link_ipip_alloc();
        if (!link)
                return -NLE_NOMEM;
 
        if(name)
                rtnl_link_set_name(link, name);
 
        err = rtnl_link_add(sk, link, NLM_F_CREATE);
        rtnl_link_put(link);
 
        return err;
}
 
/**
 * Set IPIP tunnel interface index
 * @arg link            Link object
 * @arg index           interface index
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_link(struct rtnl_link *link,  uint32_t index)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->link = index;
        ipip->ipip_mask |= IPIP_ATTR_LINK;
 
        return 0;
}
 
/**
 * Get IPIP tunnel interface index
 * @arg link            Link object
 *
 * @return interface index value
 */
uint32_t rtnl_link_ipip_get_link(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        return ipip->link;
}
 
/**
 * Set IPIP tunnel local address
 * @arg link            Link object
 * @arg addr            local address
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_local(struct rtnl_link *link, uint32_t addr)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->local = addr;
        ipip->ipip_mask |= IPIP_ATTR_LOCAL;
 
        return 0;
}
 
/**
 * Get IPIP tunnel local address
 * @arg link            Link object
 *
 * @return local address value
 */
uint32_t rtnl_link_ipip_get_local(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        return ipip->local;
}
 
/**
 * Set IPIP tunnel remote address
 * @arg link            Link object
 * @arg remote          remote address
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_remote(struct rtnl_link *link, uint32_t addr)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->remote = addr;
        ipip->ipip_mask |= IPIP_ATTR_REMOTE;
 
        return 0;
}
 
/**
 * Get IPIP tunnel remote address
 * @arg link            Link object
 *
 * @return remote address
 */
uint32_t rtnl_link_ipip_get_remote(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        return ipip->remote;
}
 
/**
 * Set IPIP tunnel ttl
 * @arg link            Link object
 * @arg ttl             tunnel ttl
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_ttl(struct rtnl_link *link, uint8_t ttl)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->ttl = ttl;
        ipip->ipip_mask |= IPIP_ATTR_TTL;
 
        return 0;
}
 
/**
 * Get IPIP tunnel ttl
 * @arg link            Link object
 *
 * @return ttl value
 */
uint8_t rtnl_link_ipip_get_ttl(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        return ipip->ttl;
}
 
/**
 * Set IPIP tunnel tos
 * @arg link            Link object
 * @arg tos             tunnel tos
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_tos(struct rtnl_link *link, uint8_t tos)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->tos = tos;
        ipip->ipip_mask |= IPIP_ATTR_TOS;
 
        return 0;
}
 
/**
 * Get IPIP tunnel tos
 * @arg link            Link object
 *
 * @return tos value
 */
uint8_t rtnl_link_ipip_get_tos(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        return ipip->tos;
}
 
/**
 * Set IPIP tunnel path MTU discovery
 * @arg link            Link object
 * @arg pmtudisc        path MTU discovery
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_pmtudisc(struct rtnl_link *link, uint8_t pmtudisc)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->pmtudisc = pmtudisc;
        ipip->ipip_mask |= IPIP_ATTR_PMTUDISC;
 
        return 0;
}
 
/**
 * Get IPIP path MTU discovery
 * @arg link            Link object
 *
 * @return pmtudisc value
 */
uint8_t rtnl_link_ipip_get_pmtudisc(struct rtnl_link *link)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        return ipip->pmtudisc;
}
 
/**
 * Set IPIP tunnel fwmark
 * @arg link            Link object
 * @arg fwmark          fwmark
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_set_fwmark(struct rtnl_link *link, uint32_t fwmark)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        ipip->fwmark = fwmark;
        ipip->ipip_mask |= IPIP_ATTR_FWMARK;
 
        return 0;
}
 
/**
 * Get IPIP tunnel fwmark
 * @arg link            Link object
 * @arg fwmark          addr to fill in with the fwmark
 *
 * @return 0 on success or a negative error code
 */
int rtnl_link_ipip_get_fwmark(struct rtnl_link *link, uint32_t *fwmark)
{
        struct ipip_info *ipip = link->l_info;
 
        IS_IPIP_LINK_ASSERT(link);
 
        if (!(ipip->ipip_mask & IPIP_ATTR_FWMARK))
                return -NLE_NOATTR;
 
        *fwmark = ipip->fwmark;
 
        return 0;
}
 
static void __init ipip_init(void)
{
        rtnl_link_register_info(&ipip_info_ops);
}
 
static void __exit ipip_exit(void)
{
        rtnl_link_unregister_info(&ipip_info_ops);
}