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/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
* Copyright (c) 2012-2014 Pablo Neira Ayuso <pablo@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_log.h>
#include <linux/netdevice.h>
static const char *nft_log_null_prefix = "";
struct nft_log {
struct nf_loginfo loginfo;
char *prefix;
};
static void nft_log_eval(const struct nft_expr *expr,
struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
const struct nft_log *priv = nft_expr_priv(expr);
nf_log_packet(pkt->net, pkt->pf, pkt->hook, pkt->skb, pkt->in,
pkt->out, &priv->loginfo, "%s", priv->prefix);
}
static const struct nla_policy nft_log_policy[NFTA_LOG_MAX + 1] = {
[NFTA_LOG_GROUP] = { .type = NLA_U16 },
[NFTA_LOG_PREFIX] = { .type = NLA_STRING },
[NFTA_LOG_SNAPLEN] = { .type = NLA_U32 },
[NFTA_LOG_QTHRESHOLD] = { .type = NLA_U16 },
[NFTA_LOG_LEVEL] = { .type = NLA_U32 },
[NFTA_LOG_FLAGS] = { .type = NLA_U32 },
};
static int nft_log_init(const struct nft_ctx *ctx,
const struct nft_expr *expr,
const struct nlattr * const tb[])
{
struct nft_log *priv = nft_expr_priv(expr);
struct nf_loginfo *li = &priv->loginfo;
const struct nlattr *nla;
int err;
li->type = NF_LOG_TYPE_LOG;
if (tb[NFTA_LOG_LEVEL] != NULL &&
tb[NFTA_LOG_GROUP] != NULL)
return -EINVAL;
if (tb[NFTA_LOG_GROUP] != NULL) {
li->type = NF_LOG_TYPE_ULOG;
if (tb[NFTA_LOG_FLAGS] != NULL)
return -EINVAL;
}
nla = tb[NFTA_LOG_PREFIX];
if (nla != NULL) {
priv->prefix = kmalloc(nla_len(nla) + 1, GFP_KERNEL);
if (priv->prefix == NULL)
return -ENOMEM;
nla_strlcpy(priv->prefix, nla, nla_len(nla) + 1);
} else {
priv->prefix = (char *)nft_log_null_prefix;
}
switch (li->type) {
case NF_LOG_TYPE_LOG:
if (tb[NFTA_LOG_LEVEL] != NULL) {
li->u.log.level =
ntohl(nla_get_be32(tb[NFTA_LOG_LEVEL]));
} else {
li->u.log.level = LOGLEVEL_WARNING;
}
if (li->u.log.level > LOGLEVEL_DEBUG) {
err = -EINVAL;
goto err1;
}
if (tb[NFTA_LOG_FLAGS] != NULL) {
li->u.log.logflags =
ntohl(nla_get_be32(tb[NFTA_LOG_FLAGS]));
if (li->u.log.logflags & ~NF_LOG_MASK) {
err = -EINVAL;
goto err1;
}
}
break;
case NF_LOG_TYPE_ULOG:
li->u.ulog.group = ntohs(nla_get_be16(tb[NFTA_LOG_GROUP]));
if (tb[NFTA_LOG_SNAPLEN] != NULL) {
li->u.ulog.flags |= NF_LOG_F_COPY_LEN;
li->u.ulog.copy_len =
ntohl(nla_get_be32(tb[NFTA_LOG_SNAPLEN]));
}
if (tb[NFTA_LOG_QTHRESHOLD] != NULL) {
li->u.ulog.qthreshold =
ntohs(nla_get_be16(tb[NFTA_LOG_QTHRESHOLD]));
}
break;
}
err = nf_logger_find_get(ctx->afi->family, li->type);
if (err < 0)
goto err1;
return 0;
err1:
if (priv->prefix != nft_log_null_prefix)
kfree(priv->prefix);
return err;
}
static void nft_log_destroy(const struct nft_ctx *ctx,
const struct nft_expr *expr)
{
struct nft_log *priv = nft_expr_priv(expr);
struct nf_loginfo *li = &priv->loginfo;
if (priv->prefix != nft_log_null_prefix)
kfree(priv->prefix);
nf_logger_put(ctx->afi->family, li->type);
}
static int nft_log_dump(struct sk_buff *skb, const struct nft_expr *expr)
{
const struct nft_log *priv = nft_expr_priv(expr);
const struct nf_loginfo *li = &priv->loginfo;
if (priv->prefix != nft_log_null_prefix)
if (nla_put_string(skb, NFTA_LOG_PREFIX, priv->prefix))
goto nla_put_failure;
switch (li->type) {
case NF_LOG_TYPE_LOG:
if (nla_put_be32(skb, NFTA_LOG_LEVEL, htonl(li->u.log.level)))
goto nla_put_failure;
if (li->u.log.logflags) {
if (nla_put_be32(skb, NFTA_LOG_FLAGS,
htonl(li->u.log.logflags)))
goto nla_put_failure;
}
break;
case NF_LOG_TYPE_ULOG:
if (nla_put_be16(skb, NFTA_LOG_GROUP, htons(li->u.ulog.group)))
goto nla_put_failure;
if (li->u.ulog.flags & NF_LOG_F_COPY_LEN) {
if (nla_put_be32(skb, NFTA_LOG_SNAPLEN,
htonl(li->u.ulog.copy_len)))
goto nla_put_failure;
}
if (li->u.ulog.qthreshold) {
if (nla_put_be16(skb, NFTA_LOG_QTHRESHOLD,
htons(li->u.ulog.qthreshold)))
goto nla_put_failure;
}
break;
}
return 0;
nla_put_failure:
return -1;
}
static struct nft_expr_type nft_log_type;
static const struct nft_expr_ops nft_log_ops = {
.type = &nft_log_type,
.size = NFT_EXPR_SIZE(sizeof(struct nft_log)),
.eval = nft_log_eval,
.init = nft_log_init,
.destroy = nft_log_destroy,
.dump = nft_log_dump,
};
static struct nft_expr_type nft_log_type __read_mostly = {
.name = "log",
.ops = &nft_log_ops,
.policy = nft_log_policy,
.maxattr = NFTA_LOG_MAX,
.owner = THIS_MODULE,
};
static int __init nft_log_module_init(void)
{
return nft_register_expr(&nft_log_type);
}
static void __exit nft_log_module_exit(void)
{
nft_unregister_expr(&nft_log_type);
}
module_init(nft_log_module_init);
module_exit(nft_log_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_EXPR("log");
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