diff options
Diffstat (limited to 'net/netfilter/nft_byteorder.c')
| -rw-r--r-- | net/netfilter/nft_byteorder.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/net/netfilter/nft_byteorder.c b/net/netfilter/nft_byteorder.c new file mode 100644 index 000000000..605178133 --- /dev/null +++ b/net/netfilter/nft_byteorder.c @@ -0,0 +1,197 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net> + * + * Development of this code funded by Astaro AG (http://www.astaro.com/) + */ + +#include <asm/unaligned.h> +#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_byteorder { + u8 sreg; + u8 dreg; + enum nft_byteorder_ops op:8; + u8 len; + u8 size; +}; + +void nft_byteorder_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) +{ + const struct nft_byteorder *priv = nft_expr_priv(expr); + u32 *src = ®s->data[priv->sreg]; + u32 *dst = ®s->data[priv->dreg]; + u16 *s16, *d16; + unsigned int i; + + s16 = (void *)src; + d16 = (void *)dst; + + switch (priv->size) { + case 8: { + u64 *dst64 = (void *)dst; + u64 src64; + + switch (priv->op) { + case NFT_BYTEORDER_NTOH: + for (i = 0; i < priv->len / 8; i++) { + src64 = nft_reg_load64(&src[i]); + nft_reg_store64(&dst64[i], + be64_to_cpu((__force __be64)src64)); + } + break; + case NFT_BYTEORDER_HTON: + for (i = 0; i < priv->len / 8; i++) { + src64 = (__force __u64) + cpu_to_be64(nft_reg_load64(&src[i])); + nft_reg_store64(&dst64[i], src64); + } + break; + } + break; + } + case 4: + switch (priv->op) { + case NFT_BYTEORDER_NTOH: + for (i = 0; i < priv->len / 4; i++) + dst[i] = ntohl((__force __be32)src[i]); + break; + case NFT_BYTEORDER_HTON: + for (i = 0; i < priv->len / 4; i++) + dst[i] = (__force __u32)htonl(src[i]); + break; + } + break; + case 2: + switch (priv->op) { + case NFT_BYTEORDER_NTOH: + for (i = 0; i < priv->len / 2; i++) + d16[i] = ntohs((__force __be16)s16[i]); + break; + case NFT_BYTEORDER_HTON: + for (i = 0; i < priv->len / 2; i++) + d16[i] = (__force __u16)htons(s16[i]); + break; + } + break; + } +} + +static const struct nla_policy nft_byteorder_policy[NFTA_BYTEORDER_MAX + 1] = { + [NFTA_BYTEORDER_SREG] = { .type = NLA_U32 }, + [NFTA_BYTEORDER_DREG] = { .type = NLA_U32 }, + [NFTA_BYTEORDER_OP] = { .type = NLA_U32 }, + [NFTA_BYTEORDER_LEN] = { .type = NLA_U32 }, + [NFTA_BYTEORDER_SIZE] = { .type = NLA_U32 }, +}; + +static int nft_byteorder_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_byteorder *priv = nft_expr_priv(expr); + u32 size, len; + int err; + + if (tb[NFTA_BYTEORDER_SREG] == NULL || + tb[NFTA_BYTEORDER_DREG] == NULL || + tb[NFTA_BYTEORDER_LEN] == NULL || + tb[NFTA_BYTEORDER_SIZE] == NULL || + tb[NFTA_BYTEORDER_OP] == NULL) + return -EINVAL; + + priv->op = ntohl(nla_get_be32(tb[NFTA_BYTEORDER_OP])); + switch (priv->op) { + case NFT_BYTEORDER_NTOH: + case NFT_BYTEORDER_HTON: + break; + default: + return -EINVAL; + } + + err = nft_parse_u32_check(tb[NFTA_BYTEORDER_SIZE], U8_MAX, &size); + if (err < 0) + return err; + + priv->size = size; + + switch (priv->size) { + case 2: + case 4: + case 8: + break; + default: + return -EINVAL; + } + + err = nft_parse_u32_check(tb[NFTA_BYTEORDER_LEN], U8_MAX, &len); + if (err < 0) + return err; + + priv->len = len; + + err = nft_parse_register_load(tb[NFTA_BYTEORDER_SREG], &priv->sreg, + priv->len); + if (err < 0) + return err; + + return nft_parse_register_store(ctx, tb[NFTA_BYTEORDER_DREG], + &priv->dreg, NULL, NFT_DATA_VALUE, + priv->len); +} + +static int nft_byteorder_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_byteorder *priv = nft_expr_priv(expr); + + if (nft_dump_register(skb, NFTA_BYTEORDER_SREG, priv->sreg)) + goto nla_put_failure; + if (nft_dump_register(skb, NFTA_BYTEORDER_DREG, priv->dreg)) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_BYTEORDER_OP, htonl(priv->op))) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_BYTEORDER_LEN, htonl(priv->len))) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_BYTEORDER_SIZE, htonl(priv->size))) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -1; +} + +static bool nft_byteorder_reduce(struct nft_regs_track *track, + const struct nft_expr *expr) +{ + struct nft_byteorder *priv = nft_expr_priv(expr); + + nft_reg_track_cancel(track, priv->dreg, priv->len); + + return false; +} + +static const struct nft_expr_ops nft_byteorder_ops = { + .type = &nft_byteorder_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_byteorder)), + .eval = nft_byteorder_eval, + .init = nft_byteorder_init, + .dump = nft_byteorder_dump, + .reduce = nft_byteorder_reduce, +}; + +struct nft_expr_type nft_byteorder_type __read_mostly = { + .name = "byteorder", + .ops = &nft_byteorder_ops, + .policy = nft_byteorder_policy, + .maxattr = NFTA_BYTEORDER_MAX, + .owner = THIS_MODULE, +}; |