1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
/*
* 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(nft_net(pkt), nft_pf(pkt), nft_hook(pkt), pkt->skb,
nft_in(pkt), nft_out(pkt), &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");
|
