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Diffstat (limited to 'src/xdp/common/rewrite_helpers.h')
| -rw-r--r-- | src/xdp/common/rewrite_helpers.h | 144 |
1 files changed, 0 insertions, 144 deletions
diff --git a/src/xdp/common/rewrite_helpers.h b/src/xdp/common/rewrite_helpers.h deleted file mode 100644 index a5d3e671d..000000000 --- a/src/xdp/common/rewrite_helpers.h +++ /dev/null @@ -1,144 +0,0 @@ -/* SPDX-License-Identifier: (GPL-2.0-or-later OR BSD-2-clause) */ -/* - * This file contains functions that are used in the packetXX XDP programs to - * manipulate on packets data. The functions are marked as __always_inline, and - * fully defined in this header file to be included in the BPF program. - */ - -#ifndef __REWRITE_HELPERS_H -#define __REWRITE_HELPERS_H - -#include <linux/bpf.h> -#include <linux/ip.h> -#include <linux/ipv6.h> -#include <linux/if_ether.h> - -#include <bpf/bpf_helpers.h> -#include <bpf/bpf_endian.h> - -/* Pops the outermost VLAN tag off the packet. Returns the popped VLAN ID on - * success or negative errno on failure. - */ -static __always_inline int vlan_tag_pop(struct xdp_md *ctx, struct ethhdr *eth) -{ - void *data_end = (void *)(long)ctx->data_end; - struct ethhdr eth_cpy; - struct vlan_hdr *vlh; - __be16 h_proto; - int vlid; - - if (!proto_is_vlan(eth->h_proto)) - return -1; - - /* Careful with the parenthesis here */ - vlh = (void *)(eth + 1); - - /* Still need to do bounds checking */ - if (vlh + 1 > data_end) - return -1; - - /* Save vlan ID for returning, h_proto for updating Ethernet header */ - vlid = bpf_ntohs(vlh->h_vlan_TCI); - h_proto = vlh->h_vlan_encapsulated_proto; - - /* Make a copy of the outer Ethernet header before we cut it off */ - __builtin_memcpy(ð_cpy, eth, sizeof(eth_cpy)); - - /* Actually adjust the head pointer */ - if (bpf_xdp_adjust_head(ctx, (int)sizeof(*vlh))) - return -1; - - /* Need to re-evaluate data *and* data_end and do new bounds checking - * after adjusting head - */ - eth = (void *)(long)ctx->data; - data_end = (void *)(long)ctx->data_end; - if (eth + 1 > data_end) - return -1; - - /* Copy back the old Ethernet header and update the proto type */ - __builtin_memcpy(eth, ð_cpy, sizeof(*eth)); - eth->h_proto = h_proto; - - return vlid; -} - -/* Pushes a new VLAN tag after the Ethernet header. Returns 0 on success, - * -1 on failure. - */ -static __always_inline int vlan_tag_push(struct xdp_md *ctx, - struct ethhdr *eth, int vlid) -{ - void *data_end = (void *)(long)ctx->data_end; - struct ethhdr eth_cpy; - struct vlan_hdr *vlh; - - /* First copy the original Ethernet header */ - __builtin_memcpy(ð_cpy, eth, sizeof(eth_cpy)); - - /* Then add space in front of the packet */ - if (bpf_xdp_adjust_head(ctx, 0 - (int)sizeof(*vlh))) - return -1; - - /* Need to re-evaluate data_end and data after head adjustment, and - * bounds check, even though we know there is enough space (as we - * increased it). - */ - data_end = (void *)(long)ctx->data_end; - eth = (void *)(long)ctx->data; - - if (eth + 1 > data_end) - return -1; - - /* Copy back Ethernet header in the right place, populate VLAN tag with - * ID and proto, and set outer Ethernet header to VLAN type. - */ - __builtin_memcpy(eth, ð_cpy, sizeof(*eth)); - - vlh = (void *)(eth + 1); - - if (vlh + 1 > data_end) - return -1; - - vlh->h_vlan_TCI = bpf_htons(vlid); - vlh->h_vlan_encapsulated_proto = eth->h_proto; - - eth->h_proto = bpf_htons(ETH_P_8021Q); - return 0; -} - -/* - * Swaps destination and source MAC addresses inside an Ethernet header - */ -static __always_inline void swap_src_dst_mac(struct ethhdr *eth) -{ - __u8 h_tmp[ETH_ALEN]; - - __builtin_memcpy(h_tmp, eth->h_source, ETH_ALEN); - __builtin_memcpy(eth->h_source, eth->h_dest, ETH_ALEN); - __builtin_memcpy(eth->h_dest, h_tmp, ETH_ALEN); -} - -/* - * Swaps destination and source IPv6 addresses inside an IPv6 header - */ -static __always_inline void swap_src_dst_ipv6(struct ipv6hdr *ipv6) -{ - struct in6_addr tmp = ipv6->saddr; - - ipv6->saddr = ipv6->daddr; - ipv6->daddr = tmp; -} - -/* - * Swaps destination and source IPv4 addresses inside an IPv4 header - */ -static __always_inline void swap_src_dst_ipv4(struct iphdr *iphdr) -{ - __be32 tmp = iphdr->saddr; - - iphdr->saddr = iphdr->daddr; - iphdr->daddr = tmp; -} - -#endif /* __REWRITE_HELPERS_H */ |