1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> 4 * 5 * Development of this code funded by Astaro AG (http://www.astaro.com/) 6 */ 7 8#include <asm/unaligned.h> 9#include <linux/kernel.h> 10#include <linux/init.h> 11#include <linux/module.h> 12#include <linux/netlink.h> 13#include <linux/netfilter.h> 14#include <linux/netfilter/nf_tables.h> 15#include <net/netfilter/nf_tables_core.h> 16#include <net/netfilter/nf_tables.h> 17 18struct nft_byteorder { 19 u8 sreg; 20 u8 dreg; 21 enum nft_byteorder_ops op:8; 22 u8 len; 23 u8 size; 24}; 25 26void nft_byteorder_eval(const struct nft_expr *expr, 27 struct nft_regs *regs, 28 const struct nft_pktinfo *pkt) 29{ 30 const struct nft_byteorder *priv = nft_expr_priv(expr); 31 u32 *src = ®s->data[priv->sreg]; 32 u32 *dst = ®s->data[priv->dreg]; 33 u16 *s16, *d16; 34 unsigned int i; 35 36 s16 = (void *)src; 37 d16 = (void *)dst; 38 39 switch (priv->size) { 40 case 8: { 41 u64 *dst64 = (void *)dst; 42 u64 src64; 43 44 switch (priv->op) { 45 case NFT_BYTEORDER_NTOH: 46 for (i = 0; i < priv->len / 8; i++) { 47 src64 = nft_reg_load64(&src[i]); 48 nft_reg_store64(&dst64[i], 49 be64_to_cpu((__force __be64)src64)); 50 } 51 break; 52 case NFT_BYTEORDER_HTON: 53 for (i = 0; i < priv->len / 8; i++) { 54 src64 = (__force __u64) 55 cpu_to_be64(nft_reg_load64(&src[i])); 56 nft_reg_store64(&dst64[i], src64); 57 } 58 break; 59 } 60 break; 61 } 62 case 4: 63 switch (priv->op) { 64 case NFT_BYTEORDER_NTOH: 65 for (i = 0; i < priv->len / 4; i++) 66 dst[i] = ntohl((__force __be32)src[i]); 67 break; 68 case NFT_BYTEORDER_HTON: 69 for (i = 0; i < priv->len / 4; i++) 70 dst[i] = (__force __u32)htonl(src[i]); 71 break; 72 } 73 break; 74 case 2: 75 switch (priv->op) { 76 case NFT_BYTEORDER_NTOH: 77 for (i = 0; i < priv->len / 2; i++) 78 d16[i] = ntohs((__force __be16)s16[i]); 79 break; 80 case NFT_BYTEORDER_HTON: 81 for (i = 0; i < priv->len / 2; i++) 82 d16[i] = (__force __u16)htons(s16[i]); 83 break; 84 } 85 break; 86 } 87} 88 89static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = { 90 [NFTA_BYTEORDER_SREG] = { .type = NLA_U32 }, 91 [NFTA_BYTEORDER_DREG] = { .type = NLA_U32 }, 92 [NFTA_BYTEORDER_OP] = NLA_POLICY_MAX(NLA_BE32, 255), 93 [NFTA_BYTEORDER_LEN] = NLA_POLICY_MAX(NLA_BE32, 255), 94 [NFTA_BYTEORDER_SIZE] = NLA_POLICY_MAX(NLA_BE32, 255), 95}; 96 97static int nft_byteorder_init(const struct nft_ctx *ctx, 98 const struct nft_expr *expr, 99 const struct nlattr * const tb[]) 100{ 101 struct nft_byteorder *priv = nft_expr_priv(expr); 102 u32 size, len; 103 int err; 104 105 if (tb[NFTA_BYTEORDER_SREG] == NULL || 106 tb[NFTA_BYTEORDER_DREG] == NULL || 107 tb[NFTA_BYTEORDER_LEN] == NULL || 108 tb[NFTA_BYTEORDER_SIZE] == NULL || 109 tb[NFTA_BYTEORDER_OP] == NULL) 110 return -EINVAL; 111 112 priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP])); 113 switch (priv->op) { 114 case NFT_BYTEORDER_NTOH: 115 case NFT_BYTEORDER_HTON: 116 break; 117 default: 118 return -EINVAL; 119 } 120 121 err = nft_parse_u32_check(tb[NFTA_BYTEORDER_SIZE], U8_MAX, &size); 122 if (err < 0) 123 return err; 124 125 priv->size = size; 126 127 switch (priv->size) { 128 case 2: 129 case 4: 130 case 8: 131 break; 132 default: 133 return -EINVAL; 134 } 135 136 err = nft_parse_u32_check(tb[NFTA_BYTEORDER_LEN], U8_MAX, &len); 137 if (err < 0) 138 return err; 139 140 priv->len = len; 141 142 err = nft_parse_register_load(tb[NFTA_BYTEORDER_SREG], &priv->sreg, 143 priv->len); 144 if (err < 0) 145 return err; 146 147 return nft_parse_register_store(ctx, tb[NFTA_BYTEORDER_DREG], 148 &priv->dreg, NULL, NFT_DATA_VALUE, 149 priv->len); 150} 151 152static int nft_byteorder_dump(struct sk_buff *skb, 153 const struct nft_expr *expr, bool reset) 154{ 155 const struct nft_byteorder *priv = nft_expr_priv(expr); 156 157 if (nft_dump_register(skb, NFTA_BYTEORDER_SREG, priv->sreg)) 158 goto nla_put_failure; 159 if (nft_dump_register(skb, NFTA_BYTEORDER_DREG, priv->dreg)) 160 goto nla_put_failure; 161 if (nla_put_be32(skb, NFTA_BYTEORDER_OP, htonl(priv->op))) 162 goto nla_put_failure; 163 if (nla_put_be32(skb, NFTA_BYTEORDER_LEN, htonl(priv->len))) 164 goto nla_put_failure; 165 if (nla_put_be32(skb, NFTA_BYTEORDER_SIZE, htonl(priv->size))) 166 goto nla_put_failure; 167 return 0; 168 169nla_put_failure: 170 return -1; 171} 172 173static bool nft_byteorder_reduce(struct nft_regs_track *track, 174 const struct nft_expr *expr) 175{ 176 struct nft_byteorder *priv = nft_expr_priv(expr); 177 178 nft_reg_track_cancel(track, priv->dreg, priv->len); 179 180 return false; 181} 182 183static const struct nft_expr_ops nft_byteorder_ops = { 184 .type = &nft_byteorder_type, 185 .size = NFT_EXPR_SIZE(sizeof(struct nft_byteorder)), 186 .eval = nft_byteorder_eval, 187 .init = nft_byteorder_init, 188 .dump = nft_byteorder_dump, 189 .reduce = nft_byteorder_reduce, 190}; 191 192struct nft_expr_type nft_byteorder_type __read_mostly = { 193 .name = "byteorder", 194 .ops = &nft_byteorder_ops, 195 .policy = nft_byteorder_policy, 196 .maxattr = NFTA_BYTEORDER_MAX, 197 .owner = THIS_MODULE, 198}; 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