1 /* 2 * Copyright (c) 2013 Eric Leblond <[email protected]> 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 u8 family; 29 }; 30 31 static void nft_queue_eval(const struct nft_expr *expr, 32 struct nft_data data[NFT_REG_MAX + 1], 33 const struct nft_pktinfo *pkt) 34 { 35 struct nft_queue *priv = nft_expr_priv(expr); 36 u32 queue = priv->queuenum; 37 u32 ret; 38 39 if (priv->queues_total > 1) { 40 if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT) { 41 int cpu = smp_processor_id(); 42 43 queue = priv->queuenum + cpu % priv->queues_total; 44 } else { 45 queue = nfqueue_hash(pkt->skb, queue, 46 priv->queues_total, priv->family, 47 jhash_initval); 48 } 49 } 50 51 ret = NF_QUEUE_NR(queue); 52 if (priv->flags & NFT_QUEUE_FLAG_BYPASS) 53 ret |= NF_VERDICT_FLAG_QUEUE_BYPASS; 54 55 data[NFT_REG_VERDICT].verdict = ret; 56 } 57 58 static const struct nla_policy nft_queue_policy[NFTA_QUEUE_MAX + 1] = { 59 [NFTA_QUEUE_NUM] = { .type = NLA_U16 }, 60 [NFTA_QUEUE_TOTAL] = { .type = NLA_U16 }, 61 [NFTA_QUEUE_FLAGS] = { .type = NLA_U16 }, 62 }; 63 64 static int nft_queue_init(const struct nft_ctx *ctx, 65 const struct nft_expr *expr, 66 const struct nlattr * const tb[]) 67 { 68 struct nft_queue *priv = nft_expr_priv(expr); 69 70 if (tb[NFTA_QUEUE_NUM] == NULL) 71 return -EINVAL; 72 73 init_hashrandom(&jhash_initval); 74 priv->family = ctx->afi->family; 75 priv->queuenum = ntohs(nla_get_be16(tb[NFTA_QUEUE_NUM])); 76 77 if (tb[NFTA_QUEUE_TOTAL] != NULL) 78 priv->queues_total = ntohs(nla_get_be16(tb[NFTA_QUEUE_TOTAL])); 79 if (tb[NFTA_QUEUE_FLAGS] != NULL) { 80 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS])); 81 if (priv->flags & ~NFT_QUEUE_FLAG_MASK) 82 return -EINVAL; 83 } 84 return 0; 85 } 86 87 static int nft_queue_dump(struct sk_buff *skb, const struct nft_expr *expr) 88 { 89 const struct nft_queue *priv = nft_expr_priv(expr); 90 91 if (nla_put_be16(skb, NFTA_QUEUE_NUM, htons(priv->queuenum)) || 92 nla_put_be16(skb, NFTA_QUEUE_TOTAL, htons(priv->queues_total)) || 93 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags))) 94 goto nla_put_failure; 95 96 return 0; 97 98 nla_put_failure: 99 return -1; 100 } 101 102 static struct nft_expr_type nft_queue_type; 103 static const struct nft_expr_ops nft_queue_ops = { 104 .type = &nft_queue_type, 105 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)), 106 .eval = nft_queue_eval, 107 .init = nft_queue_init, 108 .dump = nft_queue_dump, 109 }; 110 111 static struct nft_expr_type nft_queue_type __read_mostly = { 112 .name = "queue", 113 .ops = &nft_queue_ops, 114 .policy = nft_queue_policy, 115 .maxattr = NFTA_QUEUE_MAX, 116 .owner = THIS_MODULE, 117 }; 118 119 static int __init nft_queue_module_init(void) 120 { 121 return nft_register_expr(&nft_queue_type); 122 } 123 124 static void __exit nft_queue_module_exit(void) 125 { 126 nft_unregister_expr(&nft_queue_type); 127 } 128 129 module_init(nft_queue_module_init); 130 module_exit(nft_queue_module_exit); 131 132 MODULE_LICENSE("GPL"); 133 MODULE_AUTHOR("Eric Leblond <[email protected]>"); 134 MODULE_ALIAS_NFT_EXPR("queue"); 135