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![Pablo Neira Ayuso](/assets/img/avatar_default.png)
The flow dissector representation expects the VLAN id in host byteorder.
Add the NFT_OFFLOAD_F_NETWORK2HOST flag to swap the bytes from nft_cmp.
Fixes: a82055af59
("netfilter: nft_payload: add VLAN offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
774 lines
20 KiB
C
774 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
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* Copyright (c) 2016 Pablo Neira Ayuso <pablo@netfilter.org>
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*
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* Development of this code funded by Astaro AG (http://www.astaro.com/)
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*/
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#include <linux/kernel.h>
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#include <linux/if_vlan.h>
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/netlink.h>
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#include <linux/netfilter.h>
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#include <linux/netfilter/nf_tables.h>
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#include <net/netfilter/nf_tables_core.h>
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#include <net/netfilter/nf_tables.h>
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#include <net/netfilter/nf_tables_offload.h>
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/* For layer 4 checksum field offset. */
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#include <linux/tcp.h>
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#include <linux/udp.h>
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#include <linux/icmpv6.h>
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include <net/sctp/checksum.h>
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static bool nft_payload_rebuild_vlan_hdr(const struct sk_buff *skb, int mac_off,
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struct vlan_ethhdr *veth)
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{
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if (skb_copy_bits(skb, mac_off, veth, ETH_HLEN))
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return false;
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veth->h_vlan_proto = skb->vlan_proto;
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veth->h_vlan_TCI = htons(skb_vlan_tag_get(skb));
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veth->h_vlan_encapsulated_proto = skb->protocol;
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return true;
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}
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/* add vlan header into the user buffer for if tag was removed by offloads */
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static bool
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nft_payload_copy_vlan(u32 *d, const struct sk_buff *skb, u8 offset, u8 len)
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{
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int mac_off = skb_mac_header(skb) - skb->data;
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u8 *vlanh, *dst_u8 = (u8 *) d;
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struct vlan_ethhdr veth;
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u8 vlan_hlen = 0;
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if ((skb->protocol == htons(ETH_P_8021AD) ||
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skb->protocol == htons(ETH_P_8021Q)) &&
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offset >= VLAN_ETH_HLEN && offset < VLAN_ETH_HLEN + VLAN_HLEN)
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vlan_hlen += VLAN_HLEN;
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vlanh = (u8 *) &veth;
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if (offset < VLAN_ETH_HLEN + vlan_hlen) {
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u8 ethlen = len;
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if (vlan_hlen &&
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skb_copy_bits(skb, mac_off, &veth, VLAN_ETH_HLEN) < 0)
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return false;
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else if (!nft_payload_rebuild_vlan_hdr(skb, mac_off, &veth))
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return false;
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if (offset + len > VLAN_ETH_HLEN + vlan_hlen)
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ethlen -= offset + len - VLAN_ETH_HLEN + vlan_hlen;
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memcpy(dst_u8, vlanh + offset - vlan_hlen, ethlen);
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len -= ethlen;
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if (len == 0)
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return true;
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dst_u8 += ethlen;
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offset = ETH_HLEN + vlan_hlen;
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} else {
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offset -= VLAN_HLEN + vlan_hlen;
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}
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return skb_copy_bits(skb, offset + mac_off, dst_u8, len) == 0;
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}
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void nft_payload_eval(const struct nft_expr *expr,
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struct nft_regs *regs,
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const struct nft_pktinfo *pkt)
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{
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const struct nft_payload *priv = nft_expr_priv(expr);
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const struct sk_buff *skb = pkt->skb;
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u32 *dest = ®s->data[priv->dreg];
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int offset;
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if (priv->len % NFT_REG32_SIZE)
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dest[priv->len / NFT_REG32_SIZE] = 0;
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switch (priv->base) {
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case NFT_PAYLOAD_LL_HEADER:
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if (!skb_mac_header_was_set(skb))
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goto err;
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if (skb_vlan_tag_present(skb)) {
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if (!nft_payload_copy_vlan(dest, skb,
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priv->offset, priv->len))
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goto err;
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return;
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}
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offset = skb_mac_header(skb) - skb->data;
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break;
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case NFT_PAYLOAD_NETWORK_HEADER:
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offset = skb_network_offset(skb);
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break;
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case NFT_PAYLOAD_TRANSPORT_HEADER:
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if (!pkt->tprot_set)
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goto err;
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offset = pkt->xt.thoff;
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break;
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default:
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BUG();
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}
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offset += priv->offset;
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if (skb_copy_bits(skb, offset, dest, priv->len) < 0)
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goto err;
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return;
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err:
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regs->verdict.code = NFT_BREAK;
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}
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static const struct nla_policy nft_payload_policy[NFTA_PAYLOAD_MAX + 1] = {
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[NFTA_PAYLOAD_SREG] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_DREG] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_BASE] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_OFFSET] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_LEN] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_CSUM_TYPE] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_CSUM_OFFSET] = { .type = NLA_U32 },
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[NFTA_PAYLOAD_CSUM_FLAGS] = { .type = NLA_U32 },
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};
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static int nft_payload_init(const struct nft_ctx *ctx,
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const struct nft_expr *expr,
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const struct nlattr * const tb[])
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{
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struct nft_payload *priv = nft_expr_priv(expr);
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priv->base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
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priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
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priv->len = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
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return nft_parse_register_store(ctx, tb[NFTA_PAYLOAD_DREG],
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&priv->dreg, NULL, NFT_DATA_VALUE,
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priv->len);
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}
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static int nft_payload_dump(struct sk_buff *skb, const struct nft_expr *expr)
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{
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const struct nft_payload *priv = nft_expr_priv(expr);
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if (nft_dump_register(skb, NFTA_PAYLOAD_DREG, priv->dreg) ||
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nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
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nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
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nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)))
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goto nla_put_failure;
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return 0;
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nla_put_failure:
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return -1;
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}
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static bool nft_payload_offload_mask(struct nft_offload_reg *reg,
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u32 priv_len, u32 field_len)
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{
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unsigned int remainder, delta, k;
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struct nft_data mask = {};
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__be32 remainder_mask;
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if (priv_len == field_len) {
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memset(®->mask, 0xff, priv_len);
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return true;
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} else if (priv_len > field_len) {
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return false;
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}
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memset(&mask, 0xff, field_len);
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remainder = priv_len % sizeof(u32);
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if (remainder) {
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k = priv_len / sizeof(u32);
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delta = field_len - priv_len;
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remainder_mask = htonl(~((1 << (delta * BITS_PER_BYTE)) - 1));
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mask.data[k] = (__force u32)remainder_mask;
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}
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memcpy(®->mask, &mask, field_len);
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return true;
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}
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static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
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switch (priv->offset) {
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case offsetof(struct ethhdr, h_source):
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if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
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src, ETH_ALEN, reg);
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break;
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case offsetof(struct ethhdr, h_dest):
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if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
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dst, ETH_ALEN, reg);
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break;
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case offsetof(struct ethhdr, h_proto):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic,
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n_proto, sizeof(__be16), reg);
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nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
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break;
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case offsetof(struct vlan_ethhdr, h_vlan_TCI):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_VLAN, vlan,
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vlan_tci, sizeof(__be16), reg,
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NFT_OFFLOAD_F_NETWORK2HOST);
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break;
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case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
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vlan_tpid, sizeof(__be16), reg);
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nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
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break;
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case offsetof(struct vlan_ethhdr, h_vlan_TCI) + sizeof(struct vlan_hdr):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
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vlan_tci, sizeof(__be16), reg,
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NFT_OFFLOAD_F_NETWORK2HOST);
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break;
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case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
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sizeof(struct vlan_hdr):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
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vlan_tpid, sizeof(__be16), reg);
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nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return 0;
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}
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static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
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switch (priv->offset) {
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case offsetof(struct iphdr, saddr):
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if (!nft_payload_offload_mask(reg, priv->len,
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sizeof(struct in_addr)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src,
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sizeof(struct in_addr), reg);
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nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
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break;
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case offsetof(struct iphdr, daddr):
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if (!nft_payload_offload_mask(reg, priv->len,
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sizeof(struct in_addr)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst,
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sizeof(struct in_addr), reg);
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nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
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break;
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case offsetof(struct iphdr, protocol):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
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sizeof(__u8), reg);
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nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return 0;
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}
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static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
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switch (priv->offset) {
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case offsetof(struct ipv6hdr, saddr):
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if (!nft_payload_offload_mask(reg, priv->len,
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sizeof(struct in6_addr)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src,
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sizeof(struct in6_addr), reg);
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nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
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break;
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case offsetof(struct ipv6hdr, daddr):
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if (!nft_payload_offload_mask(reg, priv->len,
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sizeof(struct in6_addr)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst,
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sizeof(struct in6_addr), reg);
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nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
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break;
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case offsetof(struct ipv6hdr, nexthdr):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
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sizeof(__u8), reg);
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nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return 0;
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}
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static int nft_payload_offload_nh(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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int err;
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switch (ctx->dep.l3num) {
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case htons(ETH_P_IP):
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err = nft_payload_offload_ip(ctx, flow, priv);
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break;
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case htons(ETH_P_IPV6):
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err = nft_payload_offload_ip6(ctx, flow, priv);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return err;
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}
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static int nft_payload_offload_tcp(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
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switch (priv->offset) {
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case offsetof(struct tcphdr, source):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
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sizeof(__be16), reg);
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break;
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case offsetof(struct tcphdr, dest):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
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sizeof(__be16), reg);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return 0;
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}
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static int nft_payload_offload_udp(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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struct nft_offload_reg *reg = &ctx->regs[priv->dreg];
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switch (priv->offset) {
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case offsetof(struct udphdr, source):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
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sizeof(__be16), reg);
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break;
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case offsetof(struct udphdr, dest):
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if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
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return -EOPNOTSUPP;
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NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
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sizeof(__be16), reg);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return 0;
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}
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static int nft_payload_offload_th(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_payload *priv)
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{
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int err;
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switch (ctx->dep.protonum) {
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case IPPROTO_TCP:
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err = nft_payload_offload_tcp(ctx, flow, priv);
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break;
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case IPPROTO_UDP:
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err = nft_payload_offload_udp(ctx, flow, priv);
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break;
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default:
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return -EOPNOTSUPP;
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}
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return err;
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}
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static int nft_payload_offload(struct nft_offload_ctx *ctx,
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struct nft_flow_rule *flow,
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const struct nft_expr *expr)
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{
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const struct nft_payload *priv = nft_expr_priv(expr);
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int err;
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switch (priv->base) {
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case NFT_PAYLOAD_LL_HEADER:
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err = nft_payload_offload_ll(ctx, flow, priv);
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break;
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case NFT_PAYLOAD_NETWORK_HEADER:
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err = nft_payload_offload_nh(ctx, flow, priv);
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break;
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case NFT_PAYLOAD_TRANSPORT_HEADER:
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err = nft_payload_offload_th(ctx, flow, priv);
|
|
break;
|
|
default:
|
|
err = -EOPNOTSUPP;
|
|
break;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static const struct nft_expr_ops nft_payload_ops = {
|
|
.type = &nft_payload_type,
|
|
.size = NFT_EXPR_SIZE(sizeof(struct nft_payload)),
|
|
.eval = nft_payload_eval,
|
|
.init = nft_payload_init,
|
|
.dump = nft_payload_dump,
|
|
.offload = nft_payload_offload,
|
|
};
|
|
|
|
const struct nft_expr_ops nft_payload_fast_ops = {
|
|
.type = &nft_payload_type,
|
|
.size = NFT_EXPR_SIZE(sizeof(struct nft_payload)),
|
|
.eval = nft_payload_eval,
|
|
.init = nft_payload_init,
|
|
.dump = nft_payload_dump,
|
|
.offload = nft_payload_offload,
|
|
};
|
|
|
|
static inline void nft_csum_replace(__sum16 *sum, __wsum fsum, __wsum tsum)
|
|
{
|
|
*sum = csum_fold(csum_add(csum_sub(~csum_unfold(*sum), fsum), tsum));
|
|
if (*sum == 0)
|
|
*sum = CSUM_MANGLED_0;
|
|
}
|
|
|
|
static bool nft_payload_udp_checksum(struct sk_buff *skb, unsigned int thoff)
|
|
{
|
|
struct udphdr *uh, _uh;
|
|
|
|
uh = skb_header_pointer(skb, thoff, sizeof(_uh), &_uh);
|
|
if (!uh)
|
|
return false;
|
|
|
|
return (__force bool)uh->check;
|
|
}
|
|
|
|
static int nft_payload_l4csum_offset(const struct nft_pktinfo *pkt,
|
|
struct sk_buff *skb,
|
|
unsigned int *l4csum_offset)
|
|
{
|
|
switch (pkt->tprot) {
|
|
case IPPROTO_TCP:
|
|
*l4csum_offset = offsetof(struct tcphdr, check);
|
|
break;
|
|
case IPPROTO_UDP:
|
|
if (!nft_payload_udp_checksum(skb, pkt->xt.thoff))
|
|
return -1;
|
|
fallthrough;
|
|
case IPPROTO_UDPLITE:
|
|
*l4csum_offset = offsetof(struct udphdr, check);
|
|
break;
|
|
case IPPROTO_ICMPV6:
|
|
*l4csum_offset = offsetof(struct icmp6hdr, icmp6_cksum);
|
|
break;
|
|
default:
|
|
return -1;
|
|
}
|
|
|
|
*l4csum_offset += pkt->xt.thoff;
|
|
return 0;
|
|
}
|
|
|
|
static int nft_payload_csum_sctp(struct sk_buff *skb, int offset)
|
|
{
|
|
struct sctphdr *sh;
|
|
|
|
if (skb_ensure_writable(skb, offset + sizeof(*sh)))
|
|
return -1;
|
|
|
|
sh = (struct sctphdr *)(skb->data + offset);
|
|
sh->checksum = sctp_compute_cksum(skb, offset);
|
|
skb->ip_summed = CHECKSUM_UNNECESSARY;
|
|
return 0;
|
|
}
|
|
|
|
static int nft_payload_l4csum_update(const struct nft_pktinfo *pkt,
|
|
struct sk_buff *skb,
|
|
__wsum fsum, __wsum tsum)
|
|
{
|
|
int l4csum_offset;
|
|
__sum16 sum;
|
|
|
|
/* If we cannot determine layer 4 checksum offset or this packet doesn't
|
|
* require layer 4 checksum recalculation, skip this packet.
|
|
*/
|
|
if (nft_payload_l4csum_offset(pkt, skb, &l4csum_offset) < 0)
|
|
return 0;
|
|
|
|
if (skb_copy_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
|
|
return -1;
|
|
|
|
/* Checksum mangling for an arbitrary amount of bytes, based on
|
|
* inet_proto_csum_replace*() functions.
|
|
*/
|
|
if (skb->ip_summed != CHECKSUM_PARTIAL) {
|
|
nft_csum_replace(&sum, fsum, tsum);
|
|
if (skb->ip_summed == CHECKSUM_COMPLETE) {
|
|
skb->csum = ~csum_add(csum_sub(~(skb->csum), fsum),
|
|
tsum);
|
|
}
|
|
} else {
|
|
sum = ~csum_fold(csum_add(csum_sub(csum_unfold(sum), fsum),
|
|
tsum));
|
|
}
|
|
|
|
if (skb_ensure_writable(skb, l4csum_offset + sizeof(sum)) ||
|
|
skb_store_bits(skb, l4csum_offset, &sum, sizeof(sum)) < 0)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int nft_payload_csum_inet(struct sk_buff *skb, const u32 *src,
|
|
__wsum fsum, __wsum tsum, int csum_offset)
|
|
{
|
|
__sum16 sum;
|
|
|
|
if (skb_copy_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
|
|
return -1;
|
|
|
|
nft_csum_replace(&sum, fsum, tsum);
|
|
if (skb_ensure_writable(skb, csum_offset + sizeof(sum)) ||
|
|
skb_store_bits(skb, csum_offset, &sum, sizeof(sum)) < 0)
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void nft_payload_set_eval(const struct nft_expr *expr,
|
|
struct nft_regs *regs,
|
|
const struct nft_pktinfo *pkt)
|
|
{
|
|
const struct nft_payload_set *priv = nft_expr_priv(expr);
|
|
struct sk_buff *skb = pkt->skb;
|
|
const u32 *src = ®s->data[priv->sreg];
|
|
int offset, csum_offset;
|
|
__wsum fsum, tsum;
|
|
|
|
switch (priv->base) {
|
|
case NFT_PAYLOAD_LL_HEADER:
|
|
if (!skb_mac_header_was_set(skb))
|
|
goto err;
|
|
offset = skb_mac_header(skb) - skb->data;
|
|
break;
|
|
case NFT_PAYLOAD_NETWORK_HEADER:
|
|
offset = skb_network_offset(skb);
|
|
break;
|
|
case NFT_PAYLOAD_TRANSPORT_HEADER:
|
|
if (!pkt->tprot_set)
|
|
goto err;
|
|
offset = pkt->xt.thoff;
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
|
|
csum_offset = offset + priv->csum_offset;
|
|
offset += priv->offset;
|
|
|
|
if ((priv->csum_type == NFT_PAYLOAD_CSUM_INET || priv->csum_flags) &&
|
|
(priv->base != NFT_PAYLOAD_TRANSPORT_HEADER ||
|
|
skb->ip_summed != CHECKSUM_PARTIAL)) {
|
|
fsum = skb_checksum(skb, offset, priv->len, 0);
|
|
tsum = csum_partial(src, priv->len, 0);
|
|
|
|
if (priv->csum_type == NFT_PAYLOAD_CSUM_INET &&
|
|
nft_payload_csum_inet(skb, src, fsum, tsum, csum_offset))
|
|
goto err;
|
|
|
|
if (priv->csum_flags &&
|
|
nft_payload_l4csum_update(pkt, skb, fsum, tsum) < 0)
|
|
goto err;
|
|
}
|
|
|
|
if (skb_ensure_writable(skb, max(offset + priv->len, 0)) ||
|
|
skb_store_bits(skb, offset, src, priv->len) < 0)
|
|
goto err;
|
|
|
|
if (priv->csum_type == NFT_PAYLOAD_CSUM_SCTP &&
|
|
pkt->tprot == IPPROTO_SCTP &&
|
|
skb->ip_summed != CHECKSUM_PARTIAL) {
|
|
if (nft_payload_csum_sctp(skb, pkt->xt.thoff))
|
|
goto err;
|
|
}
|
|
|
|
return;
|
|
err:
|
|
regs->verdict.code = NFT_BREAK;
|
|
}
|
|
|
|
static int nft_payload_set_init(const struct nft_ctx *ctx,
|
|
const struct nft_expr *expr,
|
|
const struct nlattr * const tb[])
|
|
{
|
|
struct nft_payload_set *priv = nft_expr_priv(expr);
|
|
|
|
priv->base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
|
|
priv->offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
|
|
priv->len = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
|
|
|
|
if (tb[NFTA_PAYLOAD_CSUM_TYPE])
|
|
priv->csum_type =
|
|
ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_TYPE]));
|
|
if (tb[NFTA_PAYLOAD_CSUM_OFFSET])
|
|
priv->csum_offset =
|
|
ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_OFFSET]));
|
|
if (tb[NFTA_PAYLOAD_CSUM_FLAGS]) {
|
|
u32 flags;
|
|
|
|
flags = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_CSUM_FLAGS]));
|
|
if (flags & ~NFT_PAYLOAD_L4CSUM_PSEUDOHDR)
|
|
return -EINVAL;
|
|
|
|
priv->csum_flags = flags;
|
|
}
|
|
|
|
switch (priv->csum_type) {
|
|
case NFT_PAYLOAD_CSUM_NONE:
|
|
case NFT_PAYLOAD_CSUM_INET:
|
|
break;
|
|
case NFT_PAYLOAD_CSUM_SCTP:
|
|
if (priv->base != NFT_PAYLOAD_TRANSPORT_HEADER)
|
|
return -EINVAL;
|
|
|
|
if (priv->csum_offset != offsetof(struct sctphdr, checksum))
|
|
return -EINVAL;
|
|
break;
|
|
default:
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
return nft_parse_register_load(tb[NFTA_PAYLOAD_SREG], &priv->sreg,
|
|
priv->len);
|
|
}
|
|
|
|
static int nft_payload_set_dump(struct sk_buff *skb, const struct nft_expr *expr)
|
|
{
|
|
const struct nft_payload_set *priv = nft_expr_priv(expr);
|
|
|
|
if (nft_dump_register(skb, NFTA_PAYLOAD_SREG, priv->sreg) ||
|
|
nla_put_be32(skb, NFTA_PAYLOAD_BASE, htonl(priv->base)) ||
|
|
nla_put_be32(skb, NFTA_PAYLOAD_OFFSET, htonl(priv->offset)) ||
|
|
nla_put_be32(skb, NFTA_PAYLOAD_LEN, htonl(priv->len)) ||
|
|
nla_put_be32(skb, NFTA_PAYLOAD_CSUM_TYPE, htonl(priv->csum_type)) ||
|
|
nla_put_be32(skb, NFTA_PAYLOAD_CSUM_OFFSET,
|
|
htonl(priv->csum_offset)) ||
|
|
nla_put_be32(skb, NFTA_PAYLOAD_CSUM_FLAGS, htonl(priv->csum_flags)))
|
|
goto nla_put_failure;
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -1;
|
|
}
|
|
|
|
static const struct nft_expr_ops nft_payload_set_ops = {
|
|
.type = &nft_payload_type,
|
|
.size = NFT_EXPR_SIZE(sizeof(struct nft_payload_set)),
|
|
.eval = nft_payload_set_eval,
|
|
.init = nft_payload_set_init,
|
|
.dump = nft_payload_set_dump,
|
|
};
|
|
|
|
static const struct nft_expr_ops *
|
|
nft_payload_select_ops(const struct nft_ctx *ctx,
|
|
const struct nlattr * const tb[])
|
|
{
|
|
enum nft_payload_bases base;
|
|
unsigned int offset, len;
|
|
|
|
if (tb[NFTA_PAYLOAD_BASE] == NULL ||
|
|
tb[NFTA_PAYLOAD_OFFSET] == NULL ||
|
|
tb[NFTA_PAYLOAD_LEN] == NULL)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE]));
|
|
switch (base) {
|
|
case NFT_PAYLOAD_LL_HEADER:
|
|
case NFT_PAYLOAD_NETWORK_HEADER:
|
|
case NFT_PAYLOAD_TRANSPORT_HEADER:
|
|
break;
|
|
default:
|
|
return ERR_PTR(-EOPNOTSUPP);
|
|
}
|
|
|
|
if (tb[NFTA_PAYLOAD_SREG] != NULL) {
|
|
if (tb[NFTA_PAYLOAD_DREG] != NULL)
|
|
return ERR_PTR(-EINVAL);
|
|
return &nft_payload_set_ops;
|
|
}
|
|
|
|
if (tb[NFTA_PAYLOAD_DREG] == NULL)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
offset = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_OFFSET]));
|
|
len = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_LEN]));
|
|
|
|
if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) &&
|
|
base != NFT_PAYLOAD_LL_HEADER)
|
|
return &nft_payload_fast_ops;
|
|
else
|
|
return &nft_payload_ops;
|
|
}
|
|
|
|
struct nft_expr_type nft_payload_type __read_mostly = {
|
|
.name = "payload",
|
|
.select_ops = nft_payload_select_ops,
|
|
.policy = nft_payload_policy,
|
|
.maxattr = NFTA_PAYLOAD_MAX,
|
|
.owner = THIS_MODULE,
|
|
};
|