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(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
 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 const struct nla_policy nft_queue_policy[NFTA_QUEUE_MAX + 1] = {
 72	[NFTA_QUEUE_NUM]	= { .type = NLA_U16 },
 73	[NFTA_QUEUE_TOTAL]	= { .type = NLA_U16 },
 74	[NFTA_QUEUE_FLAGS]	= { .type = NLA_U16 },
 75	[NFTA_QUEUE_SREG_QNUM]	= { .type = NLA_U32 },
 76};
 77
 78static int nft_queue_init(const struct nft_ctx *ctx,
 79			  const struct nft_expr *expr,
 80			  const struct nlattr * const tb[])
 81{
 82	struct nft_queue *priv = nft_expr_priv(expr);
 83	u32 maxid;
 84
 85	priv->queuenum = ntohs(nla_get_be16(tb[NFTA_QUEUE_NUM]));
 86
 87	if (tb[NFTA_QUEUE_TOTAL])
 88		priv->queues_total = ntohs(nla_get_be16(tb[NFTA_QUEUE_TOTAL]));
 89	else
 90		priv->queues_total = 1;
 91
 92	if (priv->queues_total == 0)
 93		return -EINVAL;
 94
 95	maxid = priv->queues_total - 1 + priv->queuenum;
 96	if (maxid > U16_MAX)
 97		return -ERANGE;
 98
 99	if (tb[NFTA_QUEUE_FLAGS]) {
100		priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS]));
101		if (priv->flags & ~NFT_QUEUE_FLAG_MASK)
102			return -EINVAL;
103	}
104	return 0;
105}
106
107static int nft_queue_sreg_init(const struct nft_ctx *ctx,
108			       const struct nft_expr *expr,
109			       const struct nlattr * const tb[])
110{
111	struct nft_queue *priv = nft_expr_priv(expr);
112	int err;
113
114	err = nft_parse_register_load(tb[NFTA_QUEUE_SREG_QNUM],
115				      &priv->sreg_qnum, sizeof(u32));
116	if (err < 0)
117		return err;
118
119	if (tb[NFTA_QUEUE_FLAGS]) {
120		priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS]));
121		if (priv->flags & ~NFT_QUEUE_FLAG_MASK)
122			return -EINVAL;
123		if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT)
124			return -EOPNOTSUPP;
125	}
126
127	return 0;
128}
129
130static int nft_queue_dump(struct sk_buff *skb, const struct nft_expr *expr)
131{
132	const struct nft_queue *priv = nft_expr_priv(expr);
133
134	if (nla_put_be16(skb, NFTA_QUEUE_NUM, htons(priv->queuenum)) ||
135	    nla_put_be16(skb, NFTA_QUEUE_TOTAL, htons(priv->queues_total)) ||
136	    nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags)))
137		goto nla_put_failure;
138
139	return 0;
140
141nla_put_failure:
142	return -1;
143}
144
145static int
146nft_queue_sreg_dump(struct sk_buff *skb, const struct nft_expr *expr)
147{
148	const struct nft_queue *priv = nft_expr_priv(expr);
149
150	if (nft_dump_register(skb, NFTA_QUEUE_SREG_QNUM, priv->sreg_qnum) ||
151	    nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags)))
152		goto nla_put_failure;
153
154	return 0;
155
156nla_put_failure:
157	return -1;
158}
159
160static struct nft_expr_type nft_queue_type;
161static const struct nft_expr_ops nft_queue_ops = {
162	.type		= &nft_queue_type,
163	.size		= NFT_EXPR_SIZE(sizeof(struct nft_queue)),
164	.eval		= nft_queue_eval,
165	.init		= nft_queue_init,
166	.dump		= nft_queue_dump,
167};
168
169static const struct nft_expr_ops nft_queue_sreg_ops = {
170	.type		= &nft_queue_type,
171	.size		= NFT_EXPR_SIZE(sizeof(struct nft_queue)),
172	.eval		= nft_queue_sreg_eval,
173	.init		= nft_queue_sreg_init,
174	.dump		= nft_queue_sreg_dump,
175};
176
177static const struct nft_expr_ops *
178nft_queue_select_ops(const struct nft_ctx *ctx,
179		     const struct nlattr * const tb[])
180{
181	if (tb[NFTA_QUEUE_NUM] && tb[NFTA_QUEUE_SREG_QNUM])
182		return ERR_PTR(-EINVAL);
183
184	init_hashrandom(&jhash_initval);
185
186	if (tb[NFTA_QUEUE_NUM])
187		return &nft_queue_ops;
188
189	if (tb[NFTA_QUEUE_SREG_QNUM])
190		return &nft_queue_sreg_ops;
191
192	return ERR_PTR(-EINVAL);
193}
194
195static struct nft_expr_type nft_queue_type __read_mostly = {
196	.name		= "queue",
197	.select_ops	= nft_queue_select_ops,
198	.policy		= nft_queue_policy,
199	.maxattr	= NFTA_QUEUE_MAX,
200	.owner		= THIS_MODULE,
201};
202
203static int __init nft_queue_module_init(void)
204{
205	return nft_register_expr(&nft_queue_type);
206}
207
208static void __exit nft_queue_module_exit(void)
209{
210	nft_unregister_expr(&nft_queue_type);
211}
212
213module_init(nft_queue_module_init);
214module_exit(nft_queue_module_exit);
215
216MODULE_LICENSE("GPL");
217MODULE_AUTHOR("Eric Leblond <eric@regit.org>");
218MODULE_ALIAS_NFT_EXPR("queue");
219MODULE_DESCRIPTION("Netfilter nftables queue module");