flow_dissector.c

// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>

#define CHECK_FLOW_KEYS(desc, got, expected)				\
	CHECK_ATTR(memcmp(&got, &expected, sizeof(got)) != 0,		\
	      desc,							\
	      "nhoff=%u/%u "						\
	      "thoff=%u/%u "						\
	      "addr_proto=0x%x/0x%x "					\
	      "is_frag=%u/%u "						\
	      "is_first_frag=%u/%u "					\
	      "is_encap=%u/%u "						\
	      "ip_proto=0x%x/0x%x "					\
	      "n_proto=0x%x/0x%x "					\
	      "sport=%u/%u "						\
	      "dport=%u/%u\n",						\
	      got.nhoff, expected.nhoff,				\
	      got.thoff, expected.thoff,				\
	      got.addr_proto, expected.addr_proto,			\
	      got.is_frag, expected.is_frag,				\
	      got.is_first_frag, expected.is_first_frag,		\
	      got.is_encap, expected.is_encap,				\
	      got.ip_proto, expected.ip_proto,				\
	      got.n_proto, expected.n_proto,				\
	      got.sport, expected.sport,				\
	      got.dport, expected.dport)

struct ipv4_pkt {
	struct ethhdr eth;
	struct iphdr iph;
	struct tcphdr tcp;
} __packed;

struct svlan_ipv4_pkt {
	struct ethhdr eth;
	__u16 vlan_tci;
	__u16 vlan_proto;
	struct iphdr iph;
	struct tcphdr tcp;
} __packed;

struct ipv6_pkt {
	struct ethhdr eth;
	struct ipv6hdr iph;
	struct tcphdr tcp;
} __packed;

struct dvlan_ipv6_pkt {
	struct ethhdr eth;
	__u16 vlan_tci;
	__u16 vlan_proto;
	__u16 vlan_tci2;
	__u16 vlan_proto2;
	struct ipv6hdr iph;
	struct tcphdr tcp;
} __packed;

struct test {
	const char *name;
	union {
		struct ipv4_pkt ipv4;
		struct svlan_ipv4_pkt svlan_ipv4;
		struct ipv6_pkt ipv6;
		struct dvlan_ipv6_pkt dvlan_ipv6;
	} pkt;
	struct bpf_flow_keys keys;
};

#define VLAN_HLEN	4

struct test tests[] = {
	{
		.name = "ipv4",
		.pkt.ipv4 = {
			.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
			.iph.ihl = 5,
			.iph.protocol = IPPROTO_TCP,
			.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
			.tcp.doff = 5,
		},
		.keys = {
			.nhoff = 0,
			.thoff = sizeof(struct iphdr),
			.addr_proto = ETH_P_IP,
			.ip_proto = IPPROTO_TCP,
			.n_proto = __bpf_constant_htons(ETH_P_IP),
		},
	},
	{
		.name = "ipv6",
		.pkt.ipv6 = {
			.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
			.iph.nexthdr = IPPROTO_TCP,
			.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
			.tcp.doff = 5,
		},
		.keys = {
			.nhoff = 0,
			.thoff = sizeof(struct ipv6hdr),
			.addr_proto = ETH_P_IPV6,
			.ip_proto = IPPROTO_TCP,
			.n_proto = __bpf_constant_htons(ETH_P_IPV6),
		},
	},
	{
		.name = "802.1q-ipv4",
		.pkt.svlan_ipv4 = {
			.eth.h_proto = __bpf_constant_htons(ETH_P_8021Q),
			.vlan_proto = __bpf_constant_htons(ETH_P_IP),
			.iph.ihl = 5,
			.iph.protocol = IPPROTO_TCP,
			.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
			.tcp.doff = 5,
		},
		.keys = {
			.nhoff = VLAN_HLEN,
			.thoff = VLAN_HLEN + sizeof(struct iphdr),
			.addr_proto = ETH_P_IP,
			.ip_proto = IPPROTO_TCP,
			.n_proto = __bpf_constant_htons(ETH_P_IP),
		},
	},
	{
		.name = "802.1ad-ipv6",
		.pkt.dvlan_ipv6 = {
			.eth.h_proto = __bpf_constant_htons(ETH_P_8021AD),
			.vlan_proto = __bpf_constant_htons(ETH_P_8021Q),
			.vlan_proto2 = __bpf_constant_htons(ETH_P_IPV6),
			.iph.nexthdr = IPPROTO_TCP,
			.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
			.tcp.doff = 5,
		},
		.keys = {
			.nhoff = VLAN_HLEN * 2,
			.thoff = VLAN_HLEN * 2 + sizeof(struct ipv6hdr),
			.addr_proto = ETH_P_IPV6,
			.ip_proto = IPPROTO_TCP,
			.n_proto = __bpf_constant_htons(ETH_P_IPV6),
		},
	},
};

void test_flow_dissector(void)
{
	struct bpf_object *obj;
	int i, err, prog_fd;

	err = bpf_flow_load(&obj, "./bpf_flow.o", "flow_dissector",
			    "jmp_table", &prog_fd);
	if (err) {
		error_cnt++;
		return;
	}

	for (i = 0; i < ARRAY_SIZE(tests); i++) {
		struct bpf_flow_keys flow_keys;
		struct bpf_prog_test_run_attr tattr = {
			.prog_fd = prog_fd,
			.data_in = &tests[i].pkt,
			.data_size_in = sizeof(tests[i].pkt),
			.data_out = &flow_keys,
		};

		err = bpf_prog_test_run_xattr(&tattr);
		CHECK_ATTR(tattr.data_size_out != sizeof(flow_keys) ||
			   err || tattr.retval != 1,
			   tests[i].name,
			   "err %d errno %d retval %d duration %d size %u/%lu\n",
			   err, errno, tattr.retval, tattr.duration,
			   tattr.data_size_out, sizeof(flow_keys));
		CHECK_FLOW_KEYS(tests[i].name, flow_keys, tests[i].keys);
	}

	bpf_object__close(obj);
}