1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2008 Patrick McHardy <kaber@trash.net>
5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/list.h>
12 #include <linux/rculist.h>
13 #include <linux/skbuff.h>
14 #include <linux/netlink.h>
15 #include <linux/netfilter.h>
16 #include <linux/static_key.h>
17 #include <linux/netfilter/nfnetlink.h>
18 #include <linux/netfilter/nf_tables.h>
19 #include <net/netfilter/nf_tables_core.h>
20 #include <net/netfilter/nf_tables.h>
21 #include <net/netfilter/nf_log.h>
22 #include <net/netfilter/nft_meta.h>
24 #if defined(CONFIG_RETPOLINE) && defined(CONFIG_X86)
26 static struct static_key_false nf_tables_skip_direct_calls
;
28 static bool nf_skip_indirect_calls(void)
30 return static_branch_likely(&nf_tables_skip_direct_calls
);
33 static void __init
nf_skip_indirect_calls_enable(void)
35 if (!cpu_feature_enabled(X86_FEATURE_RETPOLINE
))
36 static_branch_enable(&nf_tables_skip_direct_calls
);
39 static inline bool nf_skip_indirect_calls(void) { return false; }
41 static inline void nf_skip_indirect_calls_enable(void) { }
44 static noinline
void __nft_trace_packet(const struct nft_pktinfo
*pkt
,
45 const struct nft_verdict
*verdict
,
46 const struct nft_rule_dp
*rule
,
47 struct nft_traceinfo
*info
,
48 enum nft_trace_types type
)
50 if (!info
->trace
|| !info
->nf_trace
)
55 nft_trace_notify(pkt
, verdict
, rule
, info
);
58 static inline void nft_trace_packet(const struct nft_pktinfo
*pkt
,
59 struct nft_verdict
*verdict
,
60 struct nft_traceinfo
*info
,
61 const struct nft_rule_dp
*rule
,
62 enum nft_trace_types type
)
64 if (static_branch_unlikely(&nft_trace_enabled
)) {
65 info
->nf_trace
= pkt
->skb
->nf_trace
;
66 __nft_trace_packet(pkt
, verdict
, rule
, info
, type
);
70 static inline void nft_trace_copy_nftrace(const struct nft_pktinfo
*pkt
,
71 struct nft_traceinfo
*info
)
73 if (static_branch_unlikely(&nft_trace_enabled
))
74 info
->nf_trace
= pkt
->skb
->nf_trace
;
77 static void nft_bitwise_fast_eval(const struct nft_expr
*expr
,
78 struct nft_regs
*regs
)
80 const struct nft_bitwise_fast_expr
*priv
= nft_expr_priv(expr
);
81 u32
*src
= ®s
->data
[priv
->sreg
];
82 u32
*dst
= ®s
->data
[priv
->dreg
];
84 *dst
= (*src
& priv
->mask
) ^ priv
->xor;
87 static void nft_cmp_fast_eval(const struct nft_expr
*expr
,
88 struct nft_regs
*regs
)
90 const struct nft_cmp_fast_expr
*priv
= nft_expr_priv(expr
);
92 if (((regs
->data
[priv
->sreg
] & priv
->mask
) == priv
->data
) ^ priv
->inv
)
94 regs
->verdict
.code
= NFT_BREAK
;
97 static void nft_cmp16_fast_eval(const struct nft_expr
*expr
,
98 struct nft_regs
*regs
)
100 const struct nft_cmp16_fast_expr
*priv
= nft_expr_priv(expr
);
101 const u64
*reg_data
= (const u64
*)®s
->data
[priv
->sreg
];
102 const u64
*mask
= (const u64
*)&priv
->mask
;
103 const u64
*data
= (const u64
*)&priv
->data
;
105 if (((reg_data
[0] & mask
[0]) == data
[0] &&
106 ((reg_data
[1] & mask
[1]) == data
[1])) ^ priv
->inv
)
108 regs
->verdict
.code
= NFT_BREAK
;
111 static noinline
void __nft_trace_verdict(const struct nft_pktinfo
*pkt
,
112 struct nft_traceinfo
*info
,
113 const struct nft_rule_dp
*rule
,
114 const struct nft_regs
*regs
)
116 enum nft_trace_types type
;
118 switch (regs
->verdict
.code
) {
121 type
= NFT_TRACETYPE_RETURN
;
124 type
= NFT_TRACETYPE_RULE
;
125 /* can't access skb->nf_trace; use copy */
128 type
= NFT_TRACETYPE_RULE
;
131 info
->nf_trace
= pkt
->skb
->nf_trace
;
135 __nft_trace_packet(pkt
, ®s
->verdict
, rule
, info
, type
);
138 static inline void nft_trace_verdict(const struct nft_pktinfo
*pkt
,
139 struct nft_traceinfo
*info
,
140 const struct nft_rule_dp
*rule
,
141 const struct nft_regs
*regs
)
143 if (static_branch_unlikely(&nft_trace_enabled
))
144 __nft_trace_verdict(pkt
, info
, rule
, regs
);
147 static bool nft_payload_fast_eval(const struct nft_expr
*expr
,
148 struct nft_regs
*regs
,
149 const struct nft_pktinfo
*pkt
)
151 const struct nft_payload
*priv
= nft_expr_priv(expr
);
152 const struct sk_buff
*skb
= pkt
->skb
;
153 u32
*dest
= ®s
->data
[priv
->dreg
];
156 if (priv
->base
== NFT_PAYLOAD_NETWORK_HEADER
)
157 ptr
= skb_network_header(skb
);
159 if (!(pkt
->flags
& NFT_PKTINFO_L4PROTO
))
161 ptr
= skb_network_header(skb
) + nft_thoff(pkt
);
166 if (unlikely(ptr
+ priv
->len
> skb_tail_pointer(skb
)))
171 *(u16
*)dest
= *(u16
*)ptr
;
172 else if (priv
->len
== 4)
173 *(u32
*)dest
= *(u32
*)ptr
;
175 *(u8
*)dest
= *(u8
*)ptr
;
179 DEFINE_STATIC_KEY_FALSE(nft_counters_enabled
);
181 static noinline
void nft_update_chain_stats(const struct nft_chain
*chain
,
182 const struct nft_pktinfo
*pkt
)
184 struct nft_base_chain
*base_chain
;
185 struct nft_stats __percpu
*pstats
;
186 struct nft_stats
*stats
;
188 base_chain
= nft_base_chain(chain
);
190 pstats
= READ_ONCE(base_chain
->stats
);
193 stats
= this_cpu_ptr(pstats
);
194 u64_stats_update_begin(&stats
->syncp
);
196 stats
->bytes
+= pkt
->skb
->len
;
197 u64_stats_update_end(&stats
->syncp
);
202 struct nft_jumpstack
{
203 const struct nft_rule_dp
*rule
;
206 static void expr_call_ops_eval(const struct nft_expr
*expr
,
207 struct nft_regs
*regs
,
208 struct nft_pktinfo
*pkt
)
210 #ifdef CONFIG_RETPOLINE
213 if (nf_skip_indirect_calls())
216 e
= (unsigned long)expr
->ops
->eval
;
218 do { if ((e) == (unsigned long)(fun)) \
219 return fun(expr, regs, pkt); } while (0)
221 X(e
, nft_payload_eval
);
223 X(e
, nft_counter_eval
);
224 X(e
, nft_meta_get_eval
);
225 X(e
, nft_lookup_eval
);
226 #if IS_ENABLED(CONFIG_NFT_CT)
227 X(e
, nft_ct_get_fast_eval
);
229 X(e
, nft_range_eval
);
230 X(e
, nft_immediate_eval
);
231 X(e
, nft_byteorder_eval
);
232 X(e
, nft_dynset_eval
);
233 X(e
, nft_rt_get_eval
);
234 X(e
, nft_bitwise_eval
);
235 X(e
, nft_objref_eval
);
236 X(e
, nft_objref_map_eval
);
239 #endif /* CONFIG_RETPOLINE */
240 expr
->ops
->eval(expr
, regs
, pkt
);
243 #define nft_rule_expr_first(rule) (struct nft_expr *)&rule->data[0]
244 #define nft_rule_expr_next(expr) ((void *)expr) + expr->ops->size
245 #define nft_rule_expr_last(rule) (struct nft_expr *)&rule->data[rule->dlen]
247 #define nft_rule_dp_for_each_expr(expr, last, rule) \
248 for ((expr) = nft_rule_expr_first(rule), (last) = nft_rule_expr_last(rule); \
250 (expr) = nft_rule_expr_next(expr))
253 nft_do_chain(struct nft_pktinfo
*pkt
, void *priv
)
255 const struct nft_chain
*chain
= priv
, *basechain
= chain
;
256 const struct net
*net
= nft_net(pkt
);
257 const struct nft_expr
*expr
, *last
;
258 const struct nft_rule_dp
*rule
;
259 struct nft_regs regs
= {};
260 unsigned int stackptr
= 0;
261 struct nft_jumpstack jumpstack
[NFT_JUMP_STACK_SIZE
];
262 bool genbit
= READ_ONCE(net
->nft
.gencursor
);
263 struct nft_rule_blob
*blob
;
264 struct nft_traceinfo info
;
267 if (static_branch_unlikely(&nft_trace_enabled
))
268 nft_trace_init(&info
, pkt
, basechain
);
271 blob
= rcu_dereference(chain
->blob_gen_1
);
273 blob
= rcu_dereference(chain
->blob_gen_0
);
275 rule
= (struct nft_rule_dp
*)blob
->data
;
277 regs
.verdict
.code
= NFT_CONTINUE
;
278 for (; !rule
->is_last
; rule
= nft_rule_next(rule
)) {
279 nft_rule_dp_for_each_expr(expr
, last
, rule
) {
280 if (expr
->ops
== &nft_cmp_fast_ops
)
281 nft_cmp_fast_eval(expr
, ®s
);
282 else if (expr
->ops
== &nft_cmp16_fast_ops
)
283 nft_cmp16_fast_eval(expr
, ®s
);
284 else if (expr
->ops
== &nft_bitwise_fast_ops
)
285 nft_bitwise_fast_eval(expr
, ®s
);
286 else if (expr
->ops
!= &nft_payload_fast_ops
||
287 !nft_payload_fast_eval(expr
, ®s
, pkt
))
288 expr_call_ops_eval(expr
, ®s
, pkt
);
290 if (regs
.verdict
.code
!= NFT_CONTINUE
)
294 switch (regs
.verdict
.code
) {
296 regs
.verdict
.code
= NFT_CONTINUE
;
297 nft_trace_copy_nftrace(pkt
, &info
);
300 nft_trace_packet(pkt
, ®s
.verdict
, &info
, rule
,
307 nft_trace_verdict(pkt
, &info
, rule
, ®s
);
309 switch (regs
.verdict
.code
& NF_VERDICT_MASK
) {
314 return regs
.verdict
.code
;
317 switch (regs
.verdict
.code
) {
319 if (WARN_ON_ONCE(stackptr
>= NFT_JUMP_STACK_SIZE
))
321 jumpstack
[stackptr
].rule
= nft_rule_next(rule
);
325 chain
= regs
.verdict
.chain
;
336 rule
= jumpstack
[stackptr
].rule
;
340 nft_trace_packet(pkt
, ®s
.verdict
, &info
, NULL
, NFT_TRACETYPE_POLICY
);
342 if (static_branch_unlikely(&nft_counters_enabled
))
343 nft_update_chain_stats(basechain
, pkt
);
345 return nft_base_chain(basechain
)->policy
;
347 EXPORT_SYMBOL_GPL(nft_do_chain
);
349 static struct nft_expr_type
*nft_basic_types
[] = {
367 static struct nft_object_type
*nft_basic_objects
[] = {
368 #ifdef CONFIG_NETWORK_SECMARK
369 &nft_secmark_obj_type
,
371 &nft_counter_obj_type
,
374 int __init
nf_tables_core_module_init(void)
378 nft_counter_init_seqcount();
380 for (i
= 0; i
< ARRAY_SIZE(nft_basic_objects
); i
++) {
381 err
= nft_register_obj(nft_basic_objects
[i
]);
386 for (j
= 0; j
< ARRAY_SIZE(nft_basic_types
); j
++) {
387 err
= nft_register_expr(nft_basic_types
[j
]);
392 nf_skip_indirect_calls_enable();
398 nft_unregister_expr(nft_basic_types
[j
]);
401 nft_unregister_obj(nft_basic_objects
[i
]);
406 void nf_tables_core_module_exit(void)
410 i
= ARRAY_SIZE(nft_basic_types
);
412 nft_unregister_expr(nft_basic_types
[i
]);
414 i
= ARRAY_SIZE(nft_basic_objects
);
416 nft_unregister_obj(nft_basic_objects
[i
]);