cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

xt_AUDIT.c (3623B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Creates audit record for dropped/accepted packets
      4 *
      5 * (C) 2010-2011 Thomas Graf <tgraf@redhat.com>
      6 * (C) 2010-2011 Red Hat, Inc.
      7*/
      8
      9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
     10
     11#include <linux/audit.h>
     12#include <linux/module.h>
     13#include <linux/skbuff.h>
     14#include <linux/tcp.h>
     15#include <linux/udp.h>
     16#include <linux/if_arp.h>
     17#include <linux/netfilter/x_tables.h>
     18#include <linux/netfilter/xt_AUDIT.h>
     19#include <linux/netfilter_bridge/ebtables.h>
     20#include <net/ipv6.h>
     21#include <net/ip.h>
     22
     23MODULE_LICENSE("GPL");
     24MODULE_AUTHOR("Thomas Graf <tgraf@redhat.com>");
     25MODULE_DESCRIPTION("Xtables: creates audit records for dropped/accepted packets");
     26MODULE_ALIAS("ipt_AUDIT");
     27MODULE_ALIAS("ip6t_AUDIT");
     28MODULE_ALIAS("ebt_AUDIT");
     29MODULE_ALIAS("arpt_AUDIT");
     30
     31static bool audit_ip4(struct audit_buffer *ab, struct sk_buff *skb)
     32{
     33	struct iphdr _iph;
     34	const struct iphdr *ih;
     35
     36	ih = skb_header_pointer(skb, skb_network_offset(skb), sizeof(_iph), &_iph);
     37	if (!ih)
     38		return false;
     39
     40	audit_log_format(ab, " saddr=%pI4 daddr=%pI4 proto=%hhu",
     41			 &ih->saddr, &ih->daddr, ih->protocol);
     42
     43	return true;
     44}
     45
     46static bool audit_ip6(struct audit_buffer *ab, struct sk_buff *skb)
     47{
     48	struct ipv6hdr _ip6h;
     49	const struct ipv6hdr *ih;
     50	u8 nexthdr;
     51	__be16 frag_off;
     52
     53	ih = skb_header_pointer(skb, skb_network_offset(skb), sizeof(_ip6h), &_ip6h);
     54	if (!ih)
     55		return false;
     56
     57	nexthdr = ih->nexthdr;
     58	ipv6_skip_exthdr(skb, skb_network_offset(skb) + sizeof(_ip6h), &nexthdr, &frag_off);
     59
     60	audit_log_format(ab, " saddr=%pI6c daddr=%pI6c proto=%hhu",
     61			 &ih->saddr, &ih->daddr, nexthdr);
     62
     63	return true;
     64}
     65
     66static unsigned int
     67audit_tg(struct sk_buff *skb, const struct xt_action_param *par)
     68{
     69	struct audit_buffer *ab;
     70	int fam = -1;
     71
     72	if (audit_enabled == AUDIT_OFF)
     73		goto errout;
     74	ab = audit_log_start(NULL, GFP_ATOMIC, AUDIT_NETFILTER_PKT);
     75	if (ab == NULL)
     76		goto errout;
     77
     78	audit_log_format(ab, "mark=%#x", skb->mark);
     79
     80	switch (xt_family(par)) {
     81	case NFPROTO_BRIDGE:
     82		switch (eth_hdr(skb)->h_proto) {
     83		case htons(ETH_P_IP):
     84			fam = audit_ip4(ab, skb) ? NFPROTO_IPV4 : -1;
     85			break;
     86		case htons(ETH_P_IPV6):
     87			fam = audit_ip6(ab, skb) ? NFPROTO_IPV6 : -1;
     88			break;
     89		}
     90		break;
     91	case NFPROTO_IPV4:
     92		fam = audit_ip4(ab, skb) ? NFPROTO_IPV4 : -1;
     93		break;
     94	case NFPROTO_IPV6:
     95		fam = audit_ip6(ab, skb) ? NFPROTO_IPV6 : -1;
     96		break;
     97	}
     98
     99	if (fam == -1)
    100		audit_log_format(ab, " saddr=? daddr=? proto=-1");
    101
    102	audit_log_end(ab);
    103
    104errout:
    105	return XT_CONTINUE;
    106}
    107
    108static unsigned int
    109audit_tg_ebt(struct sk_buff *skb, const struct xt_action_param *par)
    110{
    111	audit_tg(skb, par);
    112	return EBT_CONTINUE;
    113}
    114
    115static int audit_tg_check(const struct xt_tgchk_param *par)
    116{
    117	const struct xt_audit_info *info = par->targinfo;
    118
    119	if (info->type > XT_AUDIT_TYPE_MAX) {
    120		pr_info_ratelimited("Audit type out of range (valid range: 0..%u)\n",
    121				    XT_AUDIT_TYPE_MAX);
    122		return -ERANGE;
    123	}
    124
    125	return 0;
    126}
    127
    128static struct xt_target audit_tg_reg[] __read_mostly = {
    129	{
    130		.name		= "AUDIT",
    131		.family		= NFPROTO_UNSPEC,
    132		.target		= audit_tg,
    133		.targetsize	= sizeof(struct xt_audit_info),
    134		.checkentry	= audit_tg_check,
    135		.me		= THIS_MODULE,
    136	},
    137	{
    138		.name		= "AUDIT",
    139		.family		= NFPROTO_BRIDGE,
    140		.target		= audit_tg_ebt,
    141		.targetsize	= sizeof(struct xt_audit_info),
    142		.checkentry	= audit_tg_check,
    143		.me		= THIS_MODULE,
    144	},
    145};
    146
    147static int __init audit_tg_init(void)
    148{
    149	return xt_register_targets(audit_tg_reg, ARRAY_SIZE(audit_tg_reg));
    150}
    151
    152static void __exit audit_tg_exit(void)
    153{
    154	xt_unregister_targets(audit_tg_reg, ARRAY_SIZE(audit_tg_reg));
    155}
    156
    157module_init(audit_tg_init);
    158module_exit(audit_tg_exit);