1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2013 Eric Leblond <eric@regit.org>
4 *
5 * Development of this code partly funded by OISF
6 * (http://www.openinfosecfoundation.org/)
7 */
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/netlink.h>
13#include <linux/jhash.h>
14#include <linux/netfilter.h>
15#include <linux/netfilter/nf_tables.h>
16#include <net/netfilter/nf_tables.h>
17#include <net/netfilter/nf_queue.h>
18
19static u32 jhash_initval __read_mostly;
20
21struct nft_queue {
22 u8 sreg_qnum;
23 u16 queuenum;
24 u16 queues_total;
25 u16 flags;
26};
27
28static void nft_queue_eval(const struct nft_expr *expr,
29 struct nft_regs *regs,
30 const struct nft_pktinfo *pkt)
31{
32 struct nft_queue *priv = nft_expr_priv(expr);
33 u32 queue = priv->queuenum;
34 u32 ret;
35
36 if (priv->queues_total > 1) {
37 if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT) {
38 int cpu = raw_smp_processor_id();
39
40 queue = priv->queuenum + cpu % priv->queues_total;
41 } else {
42 queue = nfqueue_hash(skb: pkt->skb, queue,
43 queues_total: priv->queues_total, family: nft_pf(pkt),
44 initval: jhash_initval);
45 }
46 }
47
48 ret = NF_QUEUE_NR(queue);
49 if (priv->flags & NFT_QUEUE_FLAG_BYPASS)
50 ret |= NF_VERDICT_FLAG_QUEUE_BYPASS;
51
52 regs->verdict.code = ret;
53}
54
55static void nft_queue_sreg_eval(const struct nft_expr *expr,
56 struct nft_regs *regs,
57 const struct nft_pktinfo *pkt)
58{
59 struct nft_queue *priv = nft_expr_priv(expr);
60 u32 queue, ret;
61
62 queue = regs->data[priv->sreg_qnum];
63
64 ret = NF_QUEUE_NR(queue);
65 if (priv->flags & NFT_QUEUE_FLAG_BYPASS)
66 ret |= NF_VERDICT_FLAG_QUEUE_BYPASS;
67
68 regs->verdict.code = ret;
69}
70
71static int nft_queue_validate(const struct nft_ctx *ctx,
72 const struct nft_expr *expr,
73 const struct nft_data **data)
74{
75 static const unsigned int supported_hooks = ((1 << NF_INET_PRE_ROUTING) |
76 (1 << NF_INET_LOCAL_IN) |
77 (1 << NF_INET_FORWARD) |
78 (1 << NF_INET_LOCAL_OUT) |
79 (1 << NF_INET_POST_ROUTING));
80
81 switch (ctx->family) {
82 case NFPROTO_IPV4:
83 case NFPROTO_IPV6:
84 case NFPROTO_INET:
85 case NFPROTO_BRIDGE:
86 break;
87 case NFPROTO_NETDEV: /* lacks okfn */
88 fallthrough;
89 default:
90 return -EOPNOTSUPP;
91 }
92
93 return nft_chain_validate_hooks(chain: ctx->chain, hook_flags: supported_hooks);
94}
95
96static const struct nla_policy nft_queue_policy[NFTA_QUEUE_MAX + 1] = {
97 [NFTA_QUEUE_NUM] = { .type = NLA_U16 },
98 [NFTA_QUEUE_TOTAL] = { .type = NLA_U16 },
99 [NFTA_QUEUE_FLAGS] = { .type = NLA_U16 },
100 [NFTA_QUEUE_SREG_QNUM] = { .type = NLA_U32 },
101};
102
103static int nft_queue_init(const struct nft_ctx *ctx,
104 const struct nft_expr *expr,
105 const struct nlattr * const tb[])
106{
107 struct nft_queue *priv = nft_expr_priv(expr);
108 u32 maxid;
109
110 priv->queuenum = ntohs(nla_get_be16(tb[NFTA_QUEUE_NUM]));
111
112 if (tb[NFTA_QUEUE_TOTAL])
113 priv->queues_total = ntohs(nla_get_be16(tb[NFTA_QUEUE_TOTAL]));
114 else
115 priv->queues_total = 1;
116
117 if (priv->queues_total == 0)
118 return -EINVAL;
119
120 maxid = priv->queues_total - 1 + priv->queuenum;
121 if (maxid > U16_MAX)
122 return -ERANGE;
123
124 if (tb[NFTA_QUEUE_FLAGS]) {
125 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS]));
126 if (priv->flags & ~NFT_QUEUE_FLAG_MASK)
127 return -EINVAL;
128 }
129 return 0;
130}
131
132static int nft_queue_sreg_init(const struct nft_ctx *ctx,
133 const struct nft_expr *expr,
134 const struct nlattr * const tb[])
135{
136 struct nft_queue *priv = nft_expr_priv(expr);
137 int err;
138
139 err = nft_parse_register_load(attr: tb[NFTA_QUEUE_SREG_QNUM],
140 sreg: &priv->sreg_qnum, len: sizeof(u32));
141 if (err < 0)
142 return err;
143
144 if (tb[NFTA_QUEUE_FLAGS]) {
145 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS]));
146 if (priv->flags & ~NFT_QUEUE_FLAG_MASK)
147 return -EINVAL;
148 if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT)
149 return -EOPNOTSUPP;
150 }
151
152 return 0;
153}
154
155static int nft_queue_dump(struct sk_buff *skb,
156 const struct nft_expr *expr, bool reset)
157{
158 const struct nft_queue *priv = nft_expr_priv(expr);
159
160 if (nla_put_be16(skb, attrtype: NFTA_QUEUE_NUM, htons(priv->queuenum)) ||
161 nla_put_be16(skb, attrtype: NFTA_QUEUE_TOTAL, htons(priv->queues_total)) ||
162 nla_put_be16(skb, attrtype: NFTA_QUEUE_FLAGS, htons(priv->flags)))
163 goto nla_put_failure;
164
165 return 0;
166
167nla_put_failure:
168 return -1;
169}
170
171static int
172nft_queue_sreg_dump(struct sk_buff *skb,
173 const struct nft_expr *expr, bool reset)
174{
175 const struct nft_queue *priv = nft_expr_priv(expr);
176
177 if (nft_dump_register(skb, attr: NFTA_QUEUE_SREG_QNUM, reg: priv->sreg_qnum) ||
178 nla_put_be16(skb, attrtype: NFTA_QUEUE_FLAGS, htons(priv->flags)))
179 goto nla_put_failure;
180
181 return 0;
182
183nla_put_failure:
184 return -1;
185}
186
187static struct nft_expr_type nft_queue_type;
188static const struct nft_expr_ops nft_queue_ops = {
189 .type = &nft_queue_type,
190 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)),
191 .eval = nft_queue_eval,
192 .init = nft_queue_init,
193 .dump = nft_queue_dump,
194 .validate = nft_queue_validate,
195 .reduce = NFT_REDUCE_READONLY,
196};
197
198static const struct nft_expr_ops nft_queue_sreg_ops = {
199 .type = &nft_queue_type,
200 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)),
201 .eval = nft_queue_sreg_eval,
202 .init = nft_queue_sreg_init,
203 .dump = nft_queue_sreg_dump,
204 .validate = nft_queue_validate,
205 .reduce = NFT_REDUCE_READONLY,
206};
207
208static const struct nft_expr_ops *
209nft_queue_select_ops(const struct nft_ctx *ctx,
210 const struct nlattr * const tb[])
211{
212 if (tb[NFTA_QUEUE_NUM] && tb[NFTA_QUEUE_SREG_QNUM])
213 return ERR_PTR(error: -EINVAL);
214
215 init_hashrandom(jhash_initval: &jhash_initval);
216
217 if (tb[NFTA_QUEUE_NUM])
218 return &nft_queue_ops;
219
220 if (tb[NFTA_QUEUE_SREG_QNUM])
221 return &nft_queue_sreg_ops;
222
223 return ERR_PTR(error: -EINVAL);
224}
225
226static struct nft_expr_type nft_queue_type __read_mostly = {
227 .name = "queue",
228 .select_ops = nft_queue_select_ops,
229 .policy = nft_queue_policy,
230 .maxattr = NFTA_QUEUE_MAX,
231 .owner = THIS_MODULE,
232};
233
234static int __init nft_queue_module_init(void)
235{
236 return nft_register_expr(&nft_queue_type);
237}
238
239static void __exit nft_queue_module_exit(void)
240{
241 nft_unregister_expr(&nft_queue_type);
242}
243
244module_init(nft_queue_module_init);
245module_exit(nft_queue_module_exit);
246
247MODULE_LICENSE("GPL");
248MODULE_AUTHOR("Eric Leblond <eric@regit.org>");
249MODULE_ALIAS_NFT_EXPR("queue");
250MODULE_DESCRIPTION("Netfilter nftables queue module");
251

source code of linux/net/netfilter/nft_queue.c