obj/connlimit.c

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * (C) 2025 by Fernando Fernandez Mancera <fmancera@suse.de>
 */

#include <stdio.h>
#include <stdint.h>
#include <arpa/inet.h>

#include <linux/netfilter/nf_tables.h>

#include <internal.h>
#include <libmnl/libmnl.h>
#include <libnftnl/object.h>

#include "obj.h"

static int nftnl_obj_connlimit_set(struct nftnl_obj *e, uint16_t type,
                                   const void *data, uint32_t data_len)
{
        struct nftnl_obj_connlimit *connlimit = nftnl_obj_data(e);

        switch(type) {
        case NFTNL_OBJ_CONNLIMIT_COUNT:
                memcpy(&connlimit->count, data, data_len);
                break;
        case NFTNL_OBJ_CONNLIMIT_FLAGS:
                memcpy(&connlimit->flags, data, data_len);
                break;
        }
        return 0;
}

static const void *nftnl_obj_connlimit_get(const struct nftnl_obj *e,
                                           uint16_t type, uint32_t *data_len)
{
        struct nftnl_obj_connlimit *connlimit = nftnl_obj_data(e);

        switch (type) {
        case NFTNL_OBJ_CONNLIMIT_COUNT:
                *data_len = sizeof(connlimit->count);
                return &connlimit->count;
        case NFTNL_OBJ_CONNLIMIT_FLAGS:
                *data_len = sizeof(connlimit->flags);
                return &connlimit->flags;
        }
        return NULL;
}

static int nftnl_obj_connlimit_cb(const struct nlattr *attr, void *data)
{
        int type = mnl_attr_get_type(attr);
        const struct nlattr **tb = data;

        if (mnl_attr_type_valid(attr, NFTA_CONNLIMIT_MAX) < 0)
                return MNL_CB_OK;

        switch (type) {
        case NFTA_CONNLIMIT_COUNT:
        case NFTA_CONNLIMIT_FLAGS:
                if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
                        abi_breakage();
                break;
        }

        tb[type] = attr;
        return MNL_CB_OK;
}

static void nftnl_obj_connlimit_build(struct nlmsghdr *nlh,
                                      const struct nftnl_obj *e)
{
        struct nftnl_obj_connlimit *connlimit = nftnl_obj_data(e);

        if (e->flags & (1 << NFTNL_OBJ_CONNLIMIT_COUNT))
                mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_COUNT,
                                 htonl(connlimit->count));
        if (e->flags & (1 << NFTNL_OBJ_CONNLIMIT_FLAGS))
                mnl_attr_put_u32(nlh, NFTA_CONNLIMIT_FLAGS,
                                 htonl(connlimit->flags));
}

static int nftnl_obj_connlimit_parse(struct nftnl_obj *e, struct nlattr *attr)
{
        struct nftnl_obj_connlimit *connlimit = nftnl_obj_data(e);
        struct nlattr *tb[NFTA_CONNLIMIT_MAX + 1] = {};

        if (mnl_attr_parse_nested(attr, nftnl_obj_connlimit_cb, tb) < 0)
                return -1;

        if (tb[NFTA_CONNLIMIT_COUNT]) {
                connlimit->count = ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_COUNT]));
                e->flags |= (1 << NFTNL_OBJ_CONNLIMIT_COUNT);
        }
        if (tb[NFTA_CONNLIMIT_FLAGS]) {
                connlimit->flags = ntohl(mnl_attr_get_u32(tb[NFTA_CONNLIMIT_FLAGS]));
                e->flags |= (1 << NFTNL_OBJ_CONNLIMIT_FLAGS);
        }

        return 0;
}

static int nftnl_obj_connlimit_snprintf(char *buf, size_t len,
                                        uint32_t flags,
                                        const struct nftnl_obj *e)
{
        struct nftnl_obj_connlimit *connlimit = nftnl_obj_data(e);

        return snprintf(buf, len, "count %u flags %x ",
                        connlimit->count, connlimit->flags);
}

static struct attr_policy obj_connlimit_attr_policy[__NFTNL_OBJ_CONNLIMIT_MAX] = {
        [NFTNL_OBJ_CONNLIMIT_COUNT]     = { .maxlen = sizeof(uint32_t) },
        [NFTNL_OBJ_CONNLIMIT_FLAGS]     = { .maxlen = sizeof(uint32_t) },
};

struct obj_ops obj_ops_connlimit = {
        .name           = "connlimit",
        .type           = NFT_OBJECT_CONNLIMIT,
        .alloc_len      = sizeof(struct nftnl_obj_connlimit),
        .nftnl_max_attr = __NFTNL_OBJ_CONNLIMIT_MAX,
        .attr_policy    = obj_connlimit_attr_policy,
        .set            = nftnl_obj_connlimit_set,
        .get            = nftnl_obj_connlimit_get,
        .parse          = nftnl_obj_connlimit_parse,
        .build          = nftnl_obj_connlimit_build,
        .output         = nftnl_obj_connlimit_snprintf,
};