Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 1 | /* |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 2 | * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 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 funded by Astaro AG (http://www.astaro.com/) |
| 9 | */ |
| 10 | |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/netlink.h> |
| 15 | #include <linux/netfilter.h> |
| 16 | #include <linux/netfilter/nf_tables.h> |
| 17 | #include <net/netfilter/nf_tables_core.h> |
| 18 | #include <net/netfilter/nf_tables.h> |
| 19 | |
| 20 | struct nft_byteorder { |
| 21 | enum nft_registers sreg:8; |
| 22 | enum nft_registers dreg:8; |
| 23 | enum nft_byteorder_ops op:8; |
| 24 | u8 len; |
| 25 | u8 size; |
| 26 | }; |
| 27 | |
| 28 | static void nft_byteorder_eval(const struct nft_expr *expr, |
| 29 | struct nft_data data[NFT_REG_MAX + 1], |
| 30 | const struct nft_pktinfo *pkt) |
| 31 | { |
| 32 | const struct nft_byteorder *priv = nft_expr_priv(expr); |
| 33 | struct nft_data *src = &data[priv->sreg], *dst = &data[priv->dreg]; |
| 34 | union { u32 u32; u16 u16; } *s, *d; |
| 35 | unsigned int i; |
| 36 | |
| 37 | s = (void *)src->data; |
| 38 | d = (void *)dst->data; |
| 39 | |
| 40 | switch (priv->size) { |
| 41 | case 4: |
| 42 | switch (priv->op) { |
| 43 | case NFT_BYTEORDER_NTOH: |
| 44 | for (i = 0; i < priv->len / 4; i++) |
| 45 | d[i].u32 = ntohl((__force __be32)s[i].u32); |
| 46 | break; |
| 47 | case NFT_BYTEORDER_HTON: |
| 48 | for (i = 0; i < priv->len / 4; i++) |
| 49 | d[i].u32 = (__force __u32)htonl(s[i].u32); |
| 50 | break; |
| 51 | } |
| 52 | break; |
| 53 | case 2: |
| 54 | switch (priv->op) { |
| 55 | case NFT_BYTEORDER_NTOH: |
| 56 | for (i = 0; i < priv->len / 2; i++) |
| 57 | d[i].u16 = ntohs((__force __be16)s[i].u16); |
| 58 | break; |
| 59 | case NFT_BYTEORDER_HTON: |
| 60 | for (i = 0; i < priv->len / 2; i++) |
| 61 | d[i].u16 = (__force __u16)htons(s[i].u16); |
| 62 | break; |
| 63 | } |
| 64 | break; |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = { |
| 69 | [NFTA_BYTEORDER_SREG] = { .type = NLA_U32 }, |
| 70 | [NFTA_BYTEORDER_DREG] = { .type = NLA_U32 }, |
| 71 | [NFTA_BYTEORDER_OP] = { .type = NLA_U32 }, |
| 72 | [NFTA_BYTEORDER_LEN] = { .type = NLA_U32 }, |
| 73 | [NFTA_BYTEORDER_SIZE] = { .type = NLA_U32 }, |
| 74 | }; |
| 75 | |
| 76 | static int nft_byteorder_init(const struct nft_ctx *ctx, |
| 77 | const struct nft_expr *expr, |
| 78 | const struct nlattr * const tb[]) |
| 79 | { |
| 80 | struct nft_byteorder *priv = nft_expr_priv(expr); |
| 81 | int err; |
| 82 | |
| 83 | if (tb[NFTA_BYTEORDER_SREG] == NULL || |
| 84 | tb[NFTA_BYTEORDER_DREG] == NULL || |
| 85 | tb[NFTA_BYTEORDER_LEN] == NULL || |
| 86 | tb[NFTA_BYTEORDER_SIZE] == NULL || |
| 87 | tb[NFTA_BYTEORDER_OP] == NULL) |
| 88 | return -EINVAL; |
| 89 | |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 90 | priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP])); |
| 91 | switch (priv->op) { |
| 92 | case NFT_BYTEORDER_NTOH: |
| 93 | case NFT_BYTEORDER_HTON: |
| 94 | break; |
| 95 | default: |
| 96 | return -EINVAL; |
| 97 | } |
| 98 | |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 99 | priv->size = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_SIZE])); |
| 100 | switch (priv->size) { |
| 101 | case 2: |
| 102 | case 4: |
| 103 | break; |
| 104 | default: |
| 105 | return -EINVAL; |
| 106 | } |
| 107 | |
Patrick McHardy | 45d9bcd | 2015-04-11 02:27:26 +0100 | [diff] [blame] | 108 | priv->sreg = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_SREG])); |
Patrick McHardy | d07db98 | 2015-04-11 02:27:30 +0100 | [diff] [blame^] | 109 | priv->len = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_LEN])); |
| 110 | err = nft_validate_register_load(priv->sreg, priv->len); |
Patrick McHardy | 45d9bcd | 2015-04-11 02:27:26 +0100 | [diff] [blame] | 111 | if (err < 0) |
| 112 | return err; |
| 113 | |
| 114 | priv->dreg = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_DREG])); |
Patrick McHardy | 27e6d20 | 2015-04-11 02:27:29 +0100 | [diff] [blame] | 115 | return nft_validate_register_store(ctx, priv->dreg, NULL, |
| 116 | NFT_DATA_VALUE, priv->len); |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 117 | } |
| 118 | |
| 119 | static int nft_byteorder_dump(struct sk_buff *skb, const struct nft_expr *expr) |
| 120 | { |
| 121 | const struct nft_byteorder *priv = nft_expr_priv(expr); |
| 122 | |
| 123 | if (nla_put_be32(skb, NFTA_BYTEORDER_SREG, htonl(priv->sreg))) |
| 124 | goto nla_put_failure; |
| 125 | if (nla_put_be32(skb, NFTA_BYTEORDER_DREG, htonl(priv->dreg))) |
| 126 | goto nla_put_failure; |
| 127 | if (nla_put_be32(skb, NFTA_BYTEORDER_OP, htonl(priv->op))) |
| 128 | goto nla_put_failure; |
| 129 | if (nla_put_be32(skb, NFTA_BYTEORDER_LEN, htonl(priv->len))) |
| 130 | goto nla_put_failure; |
| 131 | if (nla_put_be32(skb, NFTA_BYTEORDER_SIZE, htonl(priv->size))) |
| 132 | goto nla_put_failure; |
| 133 | return 0; |
| 134 | |
| 135 | nla_put_failure: |
| 136 | return -1; |
| 137 | } |
| 138 | |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 139 | static struct nft_expr_type nft_byteorder_type; |
| 140 | static const struct nft_expr_ops nft_byteorder_ops = { |
| 141 | .type = &nft_byteorder_type, |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 142 | .size = NFT_EXPR_SIZE(sizeof(struct nft_byteorder)), |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 143 | .eval = nft_byteorder_eval, |
| 144 | .init = nft_byteorder_init, |
| 145 | .dump = nft_byteorder_dump, |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 146 | }; |
| 147 | |
| 148 | static struct nft_expr_type nft_byteorder_type __read_mostly = { |
| 149 | .name = "byteorder", |
| 150 | .ops = &nft_byteorder_ops, |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 151 | .policy = nft_byteorder_policy, |
| 152 | .maxattr = NFTA_BYTEORDER_MAX, |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 153 | .owner = THIS_MODULE, |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 154 | }; |
| 155 | |
| 156 | int __init nft_byteorder_module_init(void) |
| 157 | { |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 158 | return nft_register_expr(&nft_byteorder_type); |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 159 | } |
| 160 | |
| 161 | void nft_byteorder_module_exit(void) |
| 162 | { |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 163 | nft_unregister_expr(&nft_byteorder_type); |
Patrick McHardy | 9651851 | 2013-10-14 11:00:02 +0200 | [diff] [blame] | 164 | } |