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/* SPDX-License-Identifier: BSD-3-Clause
* BPF TX filter program for testing rte_bpf_eth_tx_elf_load
*/
typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned int uint32_t;
typedef unsigned long uint64_t;
/*
* Simple TX filter that accepts TCP packets
*
* BPF TX programs receive pointer to data and should return:
* 0 = drop packet
* non-zero = rx/tx packet
*
* This filter checks:
* 1. Packet is IPv4
* 2. Protocol is TCP (IPPROTO_TCP = 6)
*/
__attribute__((section("filter"), used))
uint64_t
test_filter(void *pkt)
{
uint8_t *data = pkt;
/* Read version and IHL (first byte of IP header) */
uint8_t version_ihl = data[14];
/* Check IPv4 version (upper 4 bits should be 4) */
if ((version_ihl >> 4) != 4)
return 0;
/* Protocol field (byte 9 of IP header) must be TCP (6) */
uint8_t proto = data[14 + 9];
return (proto == 6);
}
__attribute__((section("drop"), used))
uint64_t
test_drop(void *pkt)
{
(void)pkt;
return 0;
}
__attribute__((section("allow"), used))
uint64_t
test_allow(void *pkt)
{
(void)pkt;
return 1;
}
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