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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 | /* * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * Development of this code funded by Astaro AG (http://www.astaro.com/) */ #include <linux/kernel.h> #include <linux/init.h> #include <linux/module.h> #include <linux/netlink.h> #include <linux/netfilter.h> #include <linux/netfilter/nf_tables.h> #include <net/netfilter/nf_tables_core.h> #include <net/netfilter/nf_tables.h> struct nft_bitwise { enum nft_registers sreg:8; enum nft_registers dreg:8; u8 len; struct nft_data mask; struct nft_data xor; }; static void nft_bitwise_eval(const struct nft_expr *expr, struct nft_regs *regs, const struct nft_pktinfo *pkt) { const struct nft_bitwise *priv = nft_expr_priv(expr); const u32 *src = ®s->data[priv->sreg]; u32 *dst = ®s->data[priv->dreg]; unsigned int i; for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++) dst[i] = (src[i] & priv->mask.data[i]) ^ priv->xor.data[i]; } static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = { [NFTA_BITWISE_SREG] = { .type = NLA_U32 }, [NFTA_BITWISE_DREG] = { .type = NLA_U32 }, [NFTA_BITWISE_LEN] = { .type = NLA_U32 }, [NFTA_BITWISE_MASK] = { .type = NLA_NESTED }, [NFTA_BITWISE_XOR] = { .type = NLA_NESTED }, }; static int nft_bitwise_init(const struct nft_ctx *ctx, const struct nft_expr *expr, const struct nlattr * const tb[]) { struct nft_bitwise *priv = nft_expr_priv(expr); struct nft_data_desc d1, d2; u32 len; int err; if (tb[NFTA_BITWISE_SREG] == NULL || tb[NFTA_BITWISE_DREG] == NULL || tb[NFTA_BITWISE_LEN] == NULL || tb[NFTA_BITWISE_MASK] == NULL || tb[NFTA_BITWISE_XOR] == NULL) return -EINVAL; err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len); if (err < 0) return err; priv->len = len; priv->sreg = nft_parse_register(tb[NFTA_BITWISE_SREG]); err = nft_validate_register_load(priv->sreg, priv->len); if (err < 0) return err; priv->dreg = nft_parse_register(tb[NFTA_BITWISE_DREG]); err = nft_validate_register_store(ctx, priv->dreg, NULL, NFT_DATA_VALUE, priv->len); if (err < 0) return err; err = nft_data_init(NULL, &priv->mask, sizeof(priv->mask), &d1, tb[NFTA_BITWISE_MASK]); if (err < 0) return err; if (d1.len != priv->len) return -EINVAL; err = nft_data_init(NULL, &priv->xor, sizeof(priv->xor), &d2, tb[NFTA_BITWISE_XOR]); if (err < 0) return err; if (d2.len != priv->len) return -EINVAL; return 0; } static int nft_bitwise_dump(struct sk_buff *skb, const struct nft_expr *expr) { const struct nft_bitwise *priv = nft_expr_priv(expr); if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg)) goto nla_put_failure; if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg)) goto nla_put_failure; if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len))) goto nla_put_failure; if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask, NFT_DATA_VALUE, priv->len) < 0) goto nla_put_failure; if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor, NFT_DATA_VALUE, priv->len) < 0) goto nla_put_failure; return 0; nla_put_failure: return -1; } static struct nft_expr_type nft_bitwise_type; static const struct nft_expr_ops nft_bitwise_ops = { .type = &nft_bitwise_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)), .eval = nft_bitwise_eval, .init = nft_bitwise_init, .dump = nft_bitwise_dump, }; static struct nft_expr_type nft_bitwise_type __read_mostly = { .name = "bitwise", .ops = &nft_bitwise_ops, .policy = nft_bitwise_policy, .maxattr = NFTA_BITWISE_MAX, .owner = THIS_MODULE, }; int __init nft_bitwise_module_init(void) { return nft_register_expr(&nft_bitwise_type); } void nft_bitwise_module_exit(void) { nft_unregister_expr(&nft_bitwise_type); } |