1 /* 2 * Copyright (c) 2013 Eric Leblond <eric@regit.org> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * Development of this code partly funded by OISF 9 * (http://www.openinfosecfoundation.org/) 10 */ 11 12 #include <linux/kernel.h> 13 #include <linux/init.h> 14 #include <linux/module.h> 15 #include <linux/netlink.h> 16 #include <linux/jhash.h> 17 #include <linux/netfilter.h> 18 #include <linux/netfilter/nf_tables.h> 19 #include <net/netfilter/nf_tables.h> 20 #include <net/netfilter/nf_queue.h> 21 22 static u32 jhash_initval __read_mostly; 23 24 struct nft_queue { 25 u16 queuenum; 26 u16 queues_total; 27 u16 flags; 28 }; 29 30 static void nft_queue_eval(const struct nft_expr *expr, 31 struct nft_regs *regs, 32 const struct nft_pktinfo *pkt) 33 { 34 struct nft_queue *priv = nft_expr_priv(expr); 35 u32 queue = priv->queuenum; 36 u32 ret; 37 38 if (priv->queues_total > 1) { 39 if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT) { 40 int cpu = smp_processor_id(); 41 42 queue = priv->queuenum + cpu % priv->queues_total; 43 } else { 44 queue = nfqueue_hash(pkt->skb, queue, 45 priv->queues_total, pkt->pf, 46 jhash_initval); 47 } 48 } 49 50 ret = NF_QUEUE_NR(queue); 51 if (priv->flags & NFT_QUEUE_FLAG_BYPASS) 52 ret |= NF_VERDICT_FLAG_QUEUE_BYPASS; 53 54 regs->verdict.code = ret; 55 } 56 57 static const struct nla_policy nft_queue_policy[NFTA_QUEUE_MAX + 1] = { 58 [NFTA_QUEUE_NUM] = { .type = NLA_U16 }, 59 [NFTA_QUEUE_TOTAL] = { .type = NLA_U16 }, 60 [NFTA_QUEUE_FLAGS] = { .type = NLA_U16 }, 61 }; 62 63 static int nft_queue_init(const struct nft_ctx *ctx, 64 const struct nft_expr *expr, 65 const struct nlattr * const tb[]) 66 { 67 struct nft_queue *priv = nft_expr_priv(expr); 68 69 if (tb[NFTA_QUEUE_NUM] == NULL) 70 return -EINVAL; 71 72 init_hashrandom(&jhash_initval); 73 priv->queuenum = ntohs(nla_get_be16(tb[NFTA_QUEUE_NUM])); 74 75 if (tb[NFTA_QUEUE_TOTAL] != NULL) 76 priv->queues_total = ntohs(nla_get_be16(tb[NFTA_QUEUE_TOTAL])); 77 if (tb[NFTA_QUEUE_FLAGS] != NULL) { 78 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS])); 79 if (priv->flags & ~NFT_QUEUE_FLAG_MASK) 80 return -EINVAL; 81 } 82 return 0; 83 } 84 85 static int nft_queue_dump(struct sk_buff *skb, const struct nft_expr *expr) 86 { 87 const struct nft_queue *priv = nft_expr_priv(expr); 88 89 if (nla_put_be16(skb, NFTA_QUEUE_NUM, htons(priv->queuenum)) || 90 nla_put_be16(skb, NFTA_QUEUE_TOTAL, htons(priv->queues_total)) || 91 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags))) 92 goto nla_put_failure; 93 94 return 0; 95 96 nla_put_failure: 97 return -1; 98 } 99 100 static struct nft_expr_type nft_queue_type; 101 static const struct nft_expr_ops nft_queue_ops = { 102 .type = &nft_queue_type, 103 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)), 104 .eval = nft_queue_eval, 105 .init = nft_queue_init, 106 .dump = nft_queue_dump, 107 }; 108 109 static struct nft_expr_type nft_queue_type __read_mostly = { 110 .name = "queue", 111 .ops = &nft_queue_ops, 112 .policy = nft_queue_policy, 113 .maxattr = NFTA_QUEUE_MAX, 114 .owner = THIS_MODULE, 115 }; 116 117 static int __init nft_queue_module_init(void) 118 { 119 return nft_register_expr(&nft_queue_type); 120 } 121 122 static void __exit nft_queue_module_exit(void) 123 { 124 nft_unregister_expr(&nft_queue_type); 125 } 126 127 module_init(nft_queue_module_init); 128 module_exit(nft_queue_module_exit); 129 130 MODULE_LICENSE("GPL"); 131 MODULE_AUTHOR("Eric Leblond <eric@regit.org>"); 132 MODULE_ALIAS_NFT_EXPR("queue"); 133