Eric Leblond | 0aff078 | 2013-12-06 00:24:13 +0100 | [diff] [blame] | 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 | 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 <eric@regit.org>"); |
| 134 | MODULE_ALIAS_NFT_EXPR("queue"); |