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// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include <error.h>
#include <linux/if.h>
#include <linux/if_tun.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 = ETH_HLEN,
.thoff = ETH_HLEN + 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 = ETH_HLEN,
.thoff = ETH_HLEN + 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 = ETH_HLEN + VLAN_HLEN,
.thoff = ETH_HLEN + 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 = ETH_HLEN + VLAN_HLEN * 2,
.thoff = ETH_HLEN + VLAN_HLEN * 2 +
sizeof(struct ipv6hdr),
.addr_proto = ETH_P_IPV6,
.ip_proto = IPPROTO_TCP,
.n_proto = __bpf_constant_htons(ETH_P_IPV6),
},
},
};
static int create_tap(const char *ifname)
{
struct ifreq ifr = {
.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_NAPI | IFF_NAPI_FRAGS,
};
int fd, ret;
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
fd = open("/dev/net/tun", O_RDWR);
if (fd < 0)
return -1;
ret = ioctl(fd, TUNSETIFF, &ifr);
if (ret)
return -1;
return fd;
}
static int tx_tap(int fd, void *pkt, size_t len)
{
struct iovec iov[] = {
{
.iov_len = len,
.iov_base = pkt,
},
};
return writev(fd, iov, ARRAY_SIZE(iov));
}
static int ifup(const char *ifname)
{
struct ifreq ifr = {};
int sk, ret;
strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
sk = socket(PF_INET, SOCK_DGRAM, 0);
if (sk < 0)
return -1;
ret = ioctl(sk, SIOCGIFFLAGS, &ifr);
if (ret) {
close(sk);
return -1;
}
ifr.ifr_flags |= IFF_UP;
ret = ioctl(sk, SIOCSIFFLAGS, &ifr);
if (ret) {
close(sk);
return -1;
}
close(sk);
return 0;
}
void test_flow_dissector(void)
{
int i, err, prog_fd, keys_fd = -1, tap_fd;
struct bpf_object *obj;
__u32 duration = 0;
err = bpf_flow_load(&obj, "./bpf_flow.o", "flow_dissector",
"jmp_table", "last_dissection", &prog_fd, &keys_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);
}
/* Do the same tests but for skb-less flow dissector.
* We use a known path in the net/tun driver that calls
* eth_get_headlen and we manually export bpf_flow_keys
* via BPF map in this case.
*/
err = bpf_prog_attach(prog_fd, 0, BPF_FLOW_DISSECTOR, 0);
CHECK(err, "bpf_prog_attach", "err %d errno %d\n", err, errno);
tap_fd = create_tap("tap0");
CHECK(tap_fd < 0, "create_tap", "tap_fd %d errno %d\n", tap_fd, errno);
err = ifup("tap0");
CHECK(err, "ifup", "err %d errno %d\n", err, errno);
for (i = 0; i < ARRAY_SIZE(tests); i++) {
struct bpf_flow_keys flow_keys = {};
struct bpf_prog_test_run_attr tattr = {};
__u32 key = 0;
err = tx_tap(tap_fd, &tests[i].pkt, sizeof(tests[i].pkt));
CHECK(err < 0, "tx_tap", "err %d errno %d\n", err, errno);
err = bpf_map_lookup_elem(keys_fd, &key, &flow_keys);
CHECK_ATTR(err, tests[i].name, "bpf_map_lookup_elem %d\n", err);
CHECK_ATTR(err, tests[i].name, "skb-less err %d\n", err);
CHECK_FLOW_KEYS(tests[i].name, flow_keys, tests[i].keys);
}
bpf_object__close(obj);
}
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