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)71 static int nft_queue_validate(const struct nft_ctx *ctx,
72 const struct nft_expr *expr)
73 {
74 static const unsigned int supported_hooks = ((1 << NF_INET_PRE_ROUTING) |
75 (1 << NF_INET_LOCAL_IN) |
76 (1 << NF_INET_FORWARD) |
77 (1 << NF_INET_LOCAL_OUT) |
78 (1 << NF_INET_POST_ROUTING));
79
80 switch (ctx->family) {
81 case NFPROTO_IPV4:
82 case NFPROTO_IPV6:
83 case NFPROTO_INET:
84 case NFPROTO_BRIDGE:
85 break;
86 case NFPROTO_NETDEV: /* lacks okfn */
87 fallthrough;
88 default:
89 return -EOPNOTSUPP;
90 }
91
92 return nft_chain_validate_hooks(ctx->chain, supported_hooks);
93 }
94
95 static const struct nla_policy nft_queue_policy[NFTA_QUEUE_MAX + 1] = {
96 [NFTA_QUEUE_NUM] = { .type = NLA_U16 },
97 [NFTA_QUEUE_TOTAL] = { .type = NLA_U16 },
98 [NFTA_QUEUE_FLAGS] = { .type = NLA_U16 },
99 [NFTA_QUEUE_SREG_QNUM] = { .type = NLA_U32 },
100 };
101
nft_queue_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])102 static int nft_queue_init(const struct nft_ctx *ctx,
103 const struct nft_expr *expr,
104 const struct nlattr * const tb[])
105 {
106 struct nft_queue *priv = nft_expr_priv(expr);
107 u32 maxid;
108
109 priv->queuenum = ntohs(nla_get_be16(tb[NFTA_QUEUE_NUM]));
110
111 if (tb[NFTA_QUEUE_TOTAL])
112 priv->queues_total = ntohs(nla_get_be16(tb[NFTA_QUEUE_TOTAL]));
113 else
114 priv->queues_total = 1;
115
116 if (priv->queues_total == 0)
117 return -EINVAL;
118
119 maxid = priv->queues_total - 1 + priv->queuenum;
120 if (maxid > U16_MAX)
121 return -ERANGE;
122
123 if (tb[NFTA_QUEUE_FLAGS]) {
124 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS]));
125 if (priv->flags & ~NFT_QUEUE_FLAG_MASK)
126 return -EINVAL;
127 }
128 return 0;
129 }
130
nft_queue_sreg_init(const struct nft_ctx * ctx,const struct nft_expr * expr,const struct nlattr * const tb[])131 static int nft_queue_sreg_init(const struct nft_ctx *ctx,
132 const struct nft_expr *expr,
133 const struct nlattr * const tb[])
134 {
135 struct nft_queue *priv = nft_expr_priv(expr);
136 int err;
137
138 err = nft_parse_register_load(ctx, tb[NFTA_QUEUE_SREG_QNUM],
139 &priv->sreg_qnum, sizeof(u32));
140 if (err < 0)
141 return err;
142
143 if (tb[NFTA_QUEUE_FLAGS]) {
144 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS]));
145 if (priv->flags & ~NFT_QUEUE_FLAG_MASK)
146 return -EINVAL;
147 if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT)
148 return -EOPNOTSUPP;
149 }
150
151 return 0;
152 }
153
nft_queue_dump(struct sk_buff * skb,const struct nft_expr * expr,bool reset)154 static int nft_queue_dump(struct sk_buff *skb,
155 const struct nft_expr *expr, bool reset)
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,bool reset)171 nft_queue_sreg_dump(struct sk_buff *skb,
172 const struct nft_expr *expr, bool reset)
173 {
174 const struct nft_queue *priv = nft_expr_priv(expr);
175
176 if (nft_dump_register(skb, NFTA_QUEUE_SREG_QNUM, priv->sreg_qnum) ||
177 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags)))
178 goto nla_put_failure;
179
180 return 0;
181
182 nla_put_failure:
183 return -1;
184 }
185
186 static struct nft_expr_type nft_queue_type;
187 static const struct nft_expr_ops nft_queue_ops = {
188 .type = &nft_queue_type,
189 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)),
190 .eval = nft_queue_eval,
191 .init = nft_queue_init,
192 .dump = nft_queue_dump,
193 .validate = nft_queue_validate,
194 .reduce = NFT_REDUCE_READONLY,
195 };
196
197 static const struct nft_expr_ops nft_queue_sreg_ops = {
198 .type = &nft_queue_type,
199 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)),
200 .eval = nft_queue_sreg_eval,
201 .init = nft_queue_sreg_init,
202 .dump = nft_queue_sreg_dump,
203 .validate = nft_queue_validate,
204 .reduce = NFT_REDUCE_READONLY,
205 };
206
207 static const struct nft_expr_ops *
nft_queue_select_ops(const struct nft_ctx * ctx,const struct nlattr * const tb[])208 nft_queue_select_ops(const struct nft_ctx *ctx,
209 const struct nlattr * const tb[])
210 {
211 if (tb[NFTA_QUEUE_NUM] && tb[NFTA_QUEUE_SREG_QNUM])
212 return ERR_PTR(-EINVAL);
213
214 init_hashrandom(&jhash_initval);
215
216 if (tb[NFTA_QUEUE_NUM])
217 return &nft_queue_ops;
218
219 if (tb[NFTA_QUEUE_SREG_QNUM])
220 return &nft_queue_sreg_ops;
221
222 return ERR_PTR(-EINVAL);
223 }
224
225 static struct nft_expr_type nft_queue_type __read_mostly = {
226 .name = "queue",
227 .select_ops = nft_queue_select_ops,
228 .policy = nft_queue_policy,
229 .maxattr = NFTA_QUEUE_MAX,
230 .owner = THIS_MODULE,
231 };
232
nft_queue_module_init(void)233 static int __init nft_queue_module_init(void)
234 {
235 return nft_register_expr(&nft_queue_type);
236 }
237
nft_queue_module_exit(void)238 static void __exit nft_queue_module_exit(void)
239 {
240 nft_unregister_expr(&nft_queue_type);
241 }
242
243 module_init(nft_queue_module_init);
244 module_exit(nft_queue_module_exit);
245
246 MODULE_LICENSE("GPL");
247 MODULE_AUTHOR("Eric Leblond <eric@regit.org>");
248 MODULE_ALIAS_NFT_EXPR("queue");
249 MODULE_DESCRIPTION("Netfilter nftables queue module");
250