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
19 static u32 jhash_initval __read_mostly;
20
21 struct nft_queue {
22 u8 sreg_qnum;
23 u16 queuenum;
24 u16 queues_total;
25 u16 flags;
26 };
27
nft_queue_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)28 static 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(pkt->skb, queue,
43 priv->queues_total, nft_pf(pkt),
44 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
nft_queue_sreg_eval(const struct nft_expr * expr,struct nft_regs * regs,const struct nft_pktinfo * pkt)55 static 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
nft_queue_validate(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nft_data ** data)71 static 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(ctx->chain, supported_hooks);
94 }
95
96 static 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
nft_queue_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])103 static 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
nft_queue_sreg_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])132 static 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(tb[NFTA_QUEUE_SREG_QNUM],
140 &priv->sreg_qnum, 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
nft_queue_dump(struct sk_buff * skb,const struct nft_expr * expr)155 static int nft_queue_dump(struct sk_buff *skb, const struct nft_expr *expr)
156 {
157 const struct nft_queue *priv = nft_expr_priv(expr);
158
159 if (nla_put_be16(skb, NFTA_QUEUE_NUM, htons(priv->queuenum)) ||
160 nla_put_be16(skb, NFTA_QUEUE_TOTAL, htons(priv->queues_total)) ||
161 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags)))
162 goto nla_put_failure;
163
164 return 0;
165
166 nla_put_failure:
167 return -1;
168 }
169
170 static int
nft_queue_sreg_dump(struct sk_buff * skb,const struct nft_expr * expr)171 nft_queue_sreg_dump(struct sk_buff *skb, const struct nft_expr *expr)
172 {
173 const struct nft_queue *priv = nft_expr_priv(expr);
174
175 if (nft_dump_register(skb, NFTA_QUEUE_SREG_QNUM, priv->sreg_qnum) ||
176 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags)))
177 goto nla_put_failure;
178
179 return 0;
180
181 nla_put_failure:
182 return -1;
183 }
184
185 static struct nft_expr_type nft_queue_type;
186 static const struct nft_expr_ops nft_queue_ops = {
187 .type = &nft_queue_type,
188 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)),
189 .eval = nft_queue_eval,
190 .init = nft_queue_init,
191 .dump = nft_queue_dump,
192 .validate = nft_queue_validate,
193 .reduce = NFT_REDUCE_READONLY,
194 };
195
196 static const struct nft_expr_ops nft_queue_sreg_ops = {
197 .type = &nft_queue_type,
198 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)),
199 .eval = nft_queue_sreg_eval,
200 .init = nft_queue_sreg_init,
201 .dump = nft_queue_sreg_dump,
202 .validate = nft_queue_validate,
203 .reduce = NFT_REDUCE_READONLY,
204 };
205
206 static const struct nft_expr_ops *
nft_queue_select_ops(const struct nft_ctx * ctx,const struct nlattr * const tb[])207 nft_queue_select_ops(const struct nft_ctx *ctx,
208 const struct nlattr * const tb[])
209 {
210 if (tb[NFTA_QUEUE_NUM] && tb[NFTA_QUEUE_SREG_QNUM])
211 return ERR_PTR(-EINVAL);
212
213 init_hashrandom(&jhash_initval);
214
215 if (tb[NFTA_QUEUE_NUM])
216 return &nft_queue_ops;
217
218 if (tb[NFTA_QUEUE_SREG_QNUM])
219 return &nft_queue_sreg_ops;
220
221 return ERR_PTR(-EINVAL);
222 }
223
224 static struct nft_expr_type nft_queue_type __read_mostly = {
225 .name = "queue",
226 .select_ops = nft_queue_select_ops,
227 .policy = nft_queue_policy,
228 .maxattr = NFTA_QUEUE_MAX,
229 .owner = THIS_MODULE,
230 };
231
nft_queue_module_init(void)232 static int __init nft_queue_module_init(void)
233 {
234 return nft_register_expr(&nft_queue_type);
235 }
236
nft_queue_module_exit(void)237 static void __exit nft_queue_module_exit(void)
238 {
239 nft_unregister_expr(&nft_queue_type);
240 }
241
242 module_init(nft_queue_module_init);
243 module_exit(nft_queue_module_exit);
244
245 MODULE_LICENSE("GPL");
246 MODULE_AUTHOR("Eric Leblond <eric@regit.org>");
247 MODULE_ALIAS_NFT_EXPR("queue");
248 MODULE_DESCRIPTION("Netfilter nftables queue module");
249