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 enum nft_registers sreg_qnum:8; 26 u16 queuenum; 27 u16 queues_total; 28 u16 flags; 29 }; 30 31 static void nft_queue_eval(const struct nft_expr *expr, 32 struct nft_regs *regs, 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 = raw_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, nft_pf(pkt), 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 regs->verdict.code = ret; 56 } 57 58 static void nft_queue_sreg_eval(const struct nft_expr *expr, 59 struct nft_regs *regs, 60 const struct nft_pktinfo *pkt) 61 { 62 struct nft_queue *priv = nft_expr_priv(expr); 63 u32 queue, ret; 64 65 queue = regs->data[priv->sreg_qnum]; 66 67 ret = NF_QUEUE_NR(queue); 68 if (priv->flags & NFT_QUEUE_FLAG_BYPASS) 69 ret |= NF_VERDICT_FLAG_QUEUE_BYPASS; 70 71 regs->verdict.code = ret; 72 } 73 74 static const struct nla_policy nft_queue_policy[NFTA_QUEUE_MAX + 1] = { 75 [NFTA_QUEUE_NUM] = { .type = NLA_U16 }, 76 [NFTA_QUEUE_TOTAL] = { .type = NLA_U16 }, 77 [NFTA_QUEUE_FLAGS] = { .type = NLA_U16 }, 78 [NFTA_QUEUE_SREG_QNUM] = { .type = NLA_U32 }, 79 }; 80 81 static int nft_queue_init(const struct nft_ctx *ctx, 82 const struct nft_expr *expr, 83 const struct nlattr * const tb[]) 84 { 85 struct nft_queue *priv = nft_expr_priv(expr); 86 u32 maxid; 87 88 priv->queuenum = ntohs(nla_get_be16(tb[NFTA_QUEUE_NUM])); 89 90 if (tb[NFTA_QUEUE_TOTAL]) 91 priv->queues_total = ntohs(nla_get_be16(tb[NFTA_QUEUE_TOTAL])); 92 else 93 priv->queues_total = 1; 94 95 if (priv->queues_total == 0) 96 return -EINVAL; 97 98 maxid = priv->queues_total - 1 + priv->queuenum; 99 if (maxid > U16_MAX) 100 return -ERANGE; 101 102 if (tb[NFTA_QUEUE_FLAGS]) { 103 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS])); 104 if (priv->flags & ~NFT_QUEUE_FLAG_MASK) 105 return -EINVAL; 106 } 107 return 0; 108 } 109 110 static int nft_queue_sreg_init(const struct nft_ctx *ctx, 111 const struct nft_expr *expr, 112 const struct nlattr * const tb[]) 113 { 114 struct nft_queue *priv = nft_expr_priv(expr); 115 int err; 116 117 priv->sreg_qnum = nft_parse_register(tb[NFTA_QUEUE_SREG_QNUM]); 118 err = nft_validate_register_load(priv->sreg_qnum, sizeof(u32)); 119 if (err < 0) 120 return err; 121 122 if (tb[NFTA_QUEUE_FLAGS]) { 123 priv->flags = ntohs(nla_get_be16(tb[NFTA_QUEUE_FLAGS])); 124 if (priv->flags & ~NFT_QUEUE_FLAG_MASK) 125 return -EINVAL; 126 if (priv->flags & NFT_QUEUE_FLAG_CPU_FANOUT) 127 return -EOPNOTSUPP; 128 } 129 130 return 0; 131 } 132 133 static int nft_queue_dump(struct sk_buff *skb, const struct nft_expr *expr) 134 { 135 const struct nft_queue *priv = nft_expr_priv(expr); 136 137 if (nla_put_be16(skb, NFTA_QUEUE_NUM, htons(priv->queuenum)) || 138 nla_put_be16(skb, NFTA_QUEUE_TOTAL, htons(priv->queues_total)) || 139 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags))) 140 goto nla_put_failure; 141 142 return 0; 143 144 nla_put_failure: 145 return -1; 146 } 147 148 static int 149 nft_queue_sreg_dump(struct sk_buff *skb, const struct nft_expr *expr) 150 { 151 const struct nft_queue *priv = nft_expr_priv(expr); 152 153 if (nft_dump_register(skb, NFTA_QUEUE_SREG_QNUM, priv->sreg_qnum) || 154 nla_put_be16(skb, NFTA_QUEUE_FLAGS, htons(priv->flags))) 155 goto nla_put_failure; 156 157 return 0; 158 159 nla_put_failure: 160 return -1; 161 } 162 163 static struct nft_expr_type nft_queue_type; 164 static const struct nft_expr_ops nft_queue_ops = { 165 .type = &nft_queue_type, 166 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)), 167 .eval = nft_queue_eval, 168 .init = nft_queue_init, 169 .dump = nft_queue_dump, 170 }; 171 172 static const struct nft_expr_ops nft_queue_sreg_ops = { 173 .type = &nft_queue_type, 174 .size = NFT_EXPR_SIZE(sizeof(struct nft_queue)), 175 .eval = nft_queue_sreg_eval, 176 .init = nft_queue_sreg_init, 177 .dump = nft_queue_sreg_dump, 178 }; 179 180 static const struct nft_expr_ops * 181 nft_queue_select_ops(const struct nft_ctx *ctx, 182 const struct nlattr * const tb[]) 183 { 184 if (tb[NFTA_QUEUE_NUM] && tb[NFTA_QUEUE_SREG_QNUM]) 185 return ERR_PTR(-EINVAL); 186 187 init_hashrandom(&jhash_initval); 188 189 if (tb[NFTA_QUEUE_NUM]) 190 return &nft_queue_ops; 191 192 if (tb[NFTA_QUEUE_SREG_QNUM]) 193 return &nft_queue_sreg_ops; 194 195 return ERR_PTR(-EINVAL); 196 } 197 198 static struct nft_expr_type nft_queue_type __read_mostly = { 199 .name = "queue", 200 .select_ops = nft_queue_select_ops, 201 .policy = nft_queue_policy, 202 .maxattr = NFTA_QUEUE_MAX, 203 .owner = THIS_MODULE, 204 }; 205 206 static int __init nft_queue_module_init(void) 207 { 208 return nft_register_expr(&nft_queue_type); 209 } 210 211 static void __exit nft_queue_module_exit(void) 212 { 213 nft_unregister_expr(&nft_queue_type); 214 } 215 216 module_init(nft_queue_module_init); 217 module_exit(nft_queue_module_exit); 218 219 MODULE_LICENSE("GPL"); 220 MODULE_AUTHOR("Eric Leblond <eric@regit.org>"); 221 MODULE_ALIAS_NFT_EXPR("queue"); 222