| 1 | /* iptables module for using new netfilter netlink queue |
| 2 | * |
| 3 | * (C) 2005 by Harald Welte <laforge@netfilter.org> |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License version 2 as |
| 7 | * published by the Free Software Foundation. |
| 8 | * |
| 9 | */ |
| 10 | |
| 11 | #include <linux/module.h> |
| 12 | #include <linux/skbuff.h> |
| 13 | |
| 14 | #include <linux/netfilter.h> |
| 15 | #include <linux/netfilter_arp.h> |
| 16 | #include <linux/netfilter/x_tables.h> |
| 17 | #include <linux/netfilter/xt_NFQUEUE.h> |
| 18 | |
| 19 | #include <net/netfilter/nf_queue.h> |
| 20 | |
| 21 | MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>"); |
| 22 | MODULE_DESCRIPTION("Xtables: packet forwarding to netlink"); |
| 23 | MODULE_LICENSE("GPL"); |
| 24 | MODULE_ALIAS("ipt_NFQUEUE"); |
| 25 | MODULE_ALIAS("ip6t_NFQUEUE"); |
| 26 | MODULE_ALIAS("arpt_NFQUEUE"); |
| 27 | |
| 28 | static u32 jhash_initval __read_mostly; |
| 29 | |
| 30 | static unsigned int |
| 31 | nfqueue_tg(struct sk_buff *skb, const struct xt_action_param *par) |
| 32 | { |
| 33 | const struct xt_NFQ_info *tinfo = par->targinfo; |
| 34 | |
| 35 | return NF_QUEUE_NR(tinfo->queuenum); |
| 36 | } |
| 37 | |
| 38 | static unsigned int |
| 39 | nfqueue_tg_v1(struct sk_buff *skb, const struct xt_action_param *par) |
| 40 | { |
| 41 | const struct xt_NFQ_info_v1 *info = par->targinfo; |
| 42 | u32 queue = info->queuenum; |
| 43 | |
| 44 | if (info->queues_total > 1) { |
| 45 | queue = nfqueue_hash(skb, queue, info->queues_total, |
| 46 | par->family, jhash_initval); |
| 47 | } |
| 48 | return NF_QUEUE_NR(queue); |
| 49 | } |
| 50 | |
| 51 | static unsigned int |
| 52 | nfqueue_tg_v2(struct sk_buff *skb, const struct xt_action_param *par) |
| 53 | { |
| 54 | const struct xt_NFQ_info_v2 *info = par->targinfo; |
| 55 | unsigned int ret = nfqueue_tg_v1(skb, par); |
| 56 | |
| 57 | if (info->bypass) |
| 58 | ret |= NF_VERDICT_FLAG_QUEUE_BYPASS; |
| 59 | return ret; |
| 60 | } |
| 61 | |
| 62 | static int nfqueue_tg_check(const struct xt_tgchk_param *par) |
| 63 | { |
| 64 | const struct xt_NFQ_info_v3 *info = par->targinfo; |
| 65 | u32 maxid; |
| 66 | |
| 67 | init_hashrandom(&jhash_initval); |
| 68 | |
| 69 | if (info->queues_total == 0) { |
| 70 | pr_err("NFQUEUE: number of total queues is 0\n"); |
| 71 | return -EINVAL; |
| 72 | } |
| 73 | maxid = info->queues_total - 1 + info->queuenum; |
| 74 | if (maxid > 0xffff) { |
| 75 | pr_err("NFQUEUE: number of queues (%u) out of range (got %u)\n", |
| 76 | info->queues_total, maxid); |
| 77 | return -ERANGE; |
| 78 | } |
| 79 | if (par->target->revision == 2 && info->flags > 1) |
| 80 | return -EINVAL; |
| 81 | if (par->target->revision == 3 && info->flags & ~NFQ_FLAG_MASK) |
| 82 | return -EINVAL; |
| 83 | |
| 84 | return 0; |
| 85 | } |
| 86 | |
| 87 | static unsigned int |
| 88 | nfqueue_tg_v3(struct sk_buff *skb, const struct xt_action_param *par) |
| 89 | { |
| 90 | const struct xt_NFQ_info_v3 *info = par->targinfo; |
| 91 | u32 queue = info->queuenum; |
| 92 | int ret; |
| 93 | |
| 94 | if (info->queues_total > 1) { |
| 95 | if (info->flags & NFQ_FLAG_CPU_FANOUT) { |
| 96 | int cpu = smp_processor_id(); |
| 97 | |
| 98 | queue = info->queuenum + cpu % info->queues_total; |
| 99 | } else { |
| 100 | queue = nfqueue_hash(skb, queue, info->queues_total, |
| 101 | par->family, jhash_initval); |
| 102 | } |
| 103 | } |
| 104 | |
| 105 | ret = NF_QUEUE_NR(queue); |
| 106 | if (info->flags & NFQ_FLAG_BYPASS) |
| 107 | ret |= NF_VERDICT_FLAG_QUEUE_BYPASS; |
| 108 | |
| 109 | return ret; |
| 110 | } |
| 111 | |
| 112 | static struct xt_target nfqueue_tg_reg[] __read_mostly = { |
| 113 | { |
| 114 | .name = "NFQUEUE", |
| 115 | .family = NFPROTO_UNSPEC, |
| 116 | .target = nfqueue_tg, |
| 117 | .targetsize = sizeof(struct xt_NFQ_info), |
| 118 | .me = THIS_MODULE, |
| 119 | }, |
| 120 | { |
| 121 | .name = "NFQUEUE", |
| 122 | .revision = 1, |
| 123 | .family = NFPROTO_UNSPEC, |
| 124 | .checkentry = nfqueue_tg_check, |
| 125 | .target = nfqueue_tg_v1, |
| 126 | .targetsize = sizeof(struct xt_NFQ_info_v1), |
| 127 | .me = THIS_MODULE, |
| 128 | }, |
| 129 | { |
| 130 | .name = "NFQUEUE", |
| 131 | .revision = 2, |
| 132 | .family = NFPROTO_UNSPEC, |
| 133 | .checkentry = nfqueue_tg_check, |
| 134 | .target = nfqueue_tg_v2, |
| 135 | .targetsize = sizeof(struct xt_NFQ_info_v2), |
| 136 | .me = THIS_MODULE, |
| 137 | }, |
| 138 | { |
| 139 | .name = "NFQUEUE", |
| 140 | .revision = 3, |
| 141 | .family = NFPROTO_UNSPEC, |
| 142 | .checkentry = nfqueue_tg_check, |
| 143 | .target = nfqueue_tg_v3, |
| 144 | .targetsize = sizeof(struct xt_NFQ_info_v3), |
| 145 | .me = THIS_MODULE, |
| 146 | }, |
| 147 | }; |
| 148 | |
| 149 | static int __init nfqueue_tg_init(void) |
| 150 | { |
| 151 | return xt_register_targets(nfqueue_tg_reg, ARRAY_SIZE(nfqueue_tg_reg)); |
| 152 | } |
| 153 | |
| 154 | static void __exit nfqueue_tg_exit(void) |
| 155 | { |
| 156 | xt_unregister_targets(nfqueue_tg_reg, ARRAY_SIZE(nfqueue_tg_reg)); |
| 157 | } |
| 158 | |
| 159 | module_init(nfqueue_tg_init); |
| 160 | module_exit(nfqueue_tg_exit); |