// SPDX-License-Identifier: GPL-2.0
#include <test_progs.h>
#include <network_helpers.h>
#include <error.h>
#include <linux/if.h>
#include <linux/if_tun.h>
#include <sys/uio.h>
#include "bpf_flow.skel.h"
#define FLOW_CONTINUE_SADDR 0x7f00007f /* 127.0.0.127 */
#ifndef IP_MF
#define IP_MF 0x2000
#endif
#define CHECK_FLOW_KEYS(desc, got, expected) \
_CHECK(memcmp(&got, &expected, sizeof(got)) != 0, \
desc, \
topts.duration, \
"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 " \
"flow_label=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.flow_label, expected.flow_label, \
got.sport, expected.sport, \
got.dport, expected.dport)
struct ipv4_pkt {
struct ethhdr eth;
struct iphdr iph;
struct tcphdr tcp;
} __packed;
struct ipip_pkt {
struct ethhdr eth;
struct iphdr iph;
struct iphdr iph_inner;
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 ipv6_frag_pkt {
struct ethhdr eth;
struct ipv6hdr iph;
struct frag_hdr {
__u8 nexthdr;
__u8 reserved;
__be16 frag_off;
__be32 identification;
} ipf;
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 ipip_pkt ipip;
struct ipv6_pkt ipv6;
struct ipv6_frag_pkt ipv6_frag;
struct dvlan_ipv6_pkt dvlan_ipv6;
} pkt;
struct bpf_flow_keys keys;
__u32 flags;
__u32 retval;
};
#define VLAN_HLEN 4
static __u32 duration;
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,
.tcp.source = 80,
.tcp.dest = 8080,
},
.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),
.sport = 80,
.dport = 8080,
},
.retval = BPF_OK,
},
{
.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,
.tcp.source = 80,
.tcp.dest = 8080,
},
.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),
.sport = 80,
.dport = 8080,
},
.retval = BPF_OK,
},
{
.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,
.tcp.source = 80,
.tcp.dest = 8080,
},
.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),
.sport = 80,
.dport = 8080,
},
.retval = BPF_OK,
},
{
.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,
.tcp.source = 80,
.tcp.dest = 8080,
},
.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),
.sport = 80,
.dport = 8080,
},
.retval = BPF_OK,
},
{
.name = "ipv4-frag",
.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),
.iph.frag_off = __bpf_constant_htons(IP_MF),
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.keys = {
.flags = BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG,
.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),
.is_frag = true,
.is_first_frag = true,
.sport = 80,
.dport = 8080,
},
.flags = BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG,
.retval = BPF_OK,
},
{
.name = "ipv4-no-frag",
.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),
.iph.frag_off = __bpf_constant_htons(IP_MF),
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.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),
.is_frag = true,
.is_first_frag = true,
},
.retval = BPF_OK,
},
{
.name = "ipv6-frag",
.pkt.ipv6_frag = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
.iph.nexthdr = IPPROTO_FRAGMENT,
.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
.ipf.nexthdr = IPPROTO_TCP,
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.keys = {
.flags = BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG,
.nhoff = ETH_HLEN,
.thoff = ETH_HLEN + sizeof(struct ipv6hdr) +
sizeof(struct frag_hdr),
.addr_proto = ETH_P_IPV6,
.ip_proto = IPPROTO_TCP,
.n_proto = __bpf_constant_htons(ETH_P_IPV6),
.is_frag = true,
.is_first_frag = true,
.sport = 80,
.dport = 8080,
},
.flags = BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG,
.retval = BPF_OK,
},
{
.name = "ipv6-no-frag",
.pkt.ipv6_frag = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
.iph.nexthdr = IPPROTO_FRAGMENT,
.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
.ipf.nexthdr = IPPROTO_TCP,
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.keys = {
.nhoff = ETH_HLEN,
.thoff = ETH_HLEN + sizeof(struct ipv6hdr) +
sizeof(struct frag_hdr),
.addr_proto = ETH_P_IPV6,
.ip_proto = IPPROTO_TCP,
.n_proto = __bpf_constant_htons(ETH_P_IPV6),
.is_frag = true,
.is_first_frag = true,
},
.retval = BPF_OK,
},
{
.name = "ipv6-flow-label",
.pkt.ipv6 = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
.iph.nexthdr = IPPROTO_TCP,
.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
.iph.flow_lbl = { 0xb, 0xee, 0xef },
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.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),
.sport = 80,
.dport = 8080,
.flow_label = __bpf_constant_htonl(0xbeeef),
},
.retval = BPF_OK,
},
{
.name = "ipv6-no-flow-label",
.pkt.ipv6 = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
.iph.nexthdr = IPPROTO_TCP,
.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
.iph.flow_lbl = { 0xb, 0xee, 0xef },
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.keys = {
.flags = BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL,
.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),
.flow_label = __bpf_constant_htonl(0xbeeef),
},
.flags = BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL,
.retval = BPF_OK,
},
{
.name = "ipip-encap",
.pkt.ipip = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
.iph.ihl = 5,
.iph.protocol = IPPROTO_IPIP,
.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
.iph_inner.ihl = 5,
.iph_inner.protocol = IPPROTO_TCP,
.iph_inner.tot_len =
__bpf_constant_htons(MAGIC_BYTES) -
sizeof(struct iphdr),
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.keys = {
.nhoff = ETH_HLEN,
.thoff = ETH_HLEN + sizeof(struct iphdr) +
sizeof(struct iphdr),
.addr_proto = ETH_P_IP,
.ip_proto = IPPROTO_TCP,
.n_proto = __bpf_constant_htons(ETH_P_IP),
.is_encap = true,
.sport = 80,
.dport = 8080,
},
.retval = BPF_OK,
},
{
.name = "ipip-no-encap",
.pkt.ipip = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
.iph.ihl = 5,
.iph.protocol = IPPROTO_IPIP,
.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
.iph_inner.ihl = 5,
.iph_inner.protocol = IPPROTO_TCP,
.iph_inner.tot_len =
__bpf_constant_htons(MAGIC_BYTES) -
sizeof(struct iphdr),
.tcp.doff = 5,
.tcp.source = 80,
.tcp.dest = 8080,
},
.keys = {
.flags = BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP,
.nhoff = ETH_HLEN,
.thoff = ETH_HLEN + sizeof(struct iphdr),
.addr_proto = ETH_P_IP,
.ip_proto = IPPROTO_IPIP,
.n_proto = __bpf_constant_htons(ETH_P_IP),
.is_encap = true,
},
.flags = BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP,
.retval = BPF_OK,
},
{
.name = "ipip-encap-dissector-continue",
.pkt.ipip = {
.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
.iph.ihl = 5,
.iph.protocol = IPPROTO_IPIP,
.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
.iph.saddr = __bpf_constant_htonl(FLOW_CONTINUE_SADDR),
.iph_inner.ihl = 5,
.iph_inner.protocol = IPPROTO_TCP,
.iph_inner.tot_len =
__bpf_constant_htons(MAGIC_BYTES) -
sizeof(struct iphdr),
.tcp.doff = 5,
.tcp.source = 99,
.tcp.dest = 9090,
},
.retval = BPF_FLOW_DISSECTOR_CONTINUE,
},
};
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;
}
static int init_prog_array(struct bpf_object *obj, struct bpf_map *prog_array)
{
int i, err, map_fd, prog_fd;
struct bpf_program *prog;
char prog_name[32];
map_fd = bpf_map__fd(prog_array);
if (map_fd < 0)
return -1;
for (i = 0; i < bpf_map__max_entries(prog_array); i++) {
snprintf(prog_name, sizeof(prog_name), "flow_dissector_%d", i);
prog = bpf_object__find_program_by_name(obj, prog_name);
if (!prog)
return -1;
prog_fd = bpf_program__fd(prog);
if (prog_fd < 0)
return -1;
err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
if (err)
return -1;
}
return 0;
}
static void run_tests_skb_less(int tap_fd, struct bpf_map *keys)
{
int i, err, keys_fd;
keys_fd = bpf_map__fd(keys);
if (CHECK(keys_fd < 0, "bpf_map__fd", "err %d\n", keys_fd))
return;
for (i = 0; i < ARRAY_SIZE(tests); i++) {
/* Keep in sync with 'flags' from eth_get_headlen. */
__u32 eth_get_headlen_flags =
BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG;
LIBBPF_OPTS(bpf_test_run_opts, topts);
struct bpf_flow_keys flow_keys = {};
__u32 key = (__u32)(tests[i].keys.sport) << 16 |
tests[i].keys.dport;
/* For skb-less case we can't pass input flags; run
* only the tests that have a matching set of flags.
*/
if (tests[i].flags != eth_get_headlen_flags)
continue;
err = tx_tap(tap_fd, &tests[i].pkt, sizeof(tests[i].pkt));
CHECK(err < 0, "tx_tap", "err %d errno %d\n", err, errno);
/* check the stored flow_keys only if BPF_OK expected */
if (tests[i].retval != BPF_OK)
continue;
err = bpf_map_lookup_elem(keys_fd, &key, &flow_keys);
ASSERT_OK(err, "bpf_map_lookup_elem");
CHECK_FLOW_KEYS(tests[i].name, flow_keys, tests[i].keys);
err = bpf_map_delete_elem(keys_fd, &key);
ASSERT_OK(err, "bpf_map_delete_elem");
}
}
static void test_skb_less_prog_attach(struct bpf_flow *skel, int tap_fd)
{
int err, prog_fd;
prog_fd = bpf_program__fd(skel->progs._dissect);
if (CHECK(prog_fd < 0, "bpf_program__fd", "err %d\n", prog_fd))
return;
err = bpf_prog_attach(prog_fd, 0, BPF_FLOW_DISSECTOR, 0);
if (CHECK(err, "bpf_prog_attach", "err %d errno %d\n", err, errno))
return;
run_tests_skb_less(tap_fd, skel->maps.last_dissection);
err = bpf_prog_detach2(prog_fd, 0, BPF_FLOW_DISSECTOR);
CHECK(err, "bpf_prog_detach2", "err %d errno %d\n", err, errno);
}
static void test_skb_less_link_create(struct bpf_flow *skel, int tap_fd)
{
struct bpf_link *link;
int err, net_fd;
net_fd = open("/proc/self/ns/net", O_RDONLY);
if (CHECK(net_fd < 0, "open(/proc/self/ns/net)", "err %d\n", errno))
return;
link = bpf_program__attach_netns(skel->progs._dissect, net_fd);
if (!ASSERT_OK_PTR(link, "attach_netns"))
goto out_close;
run_tests_skb_less(tap_fd, skel->maps.last_dissection);
err = bpf_link__destroy(link);
CHECK(err, "bpf_link__destroy", "err %d\n", err);
out_close:
close(net_fd);
}
void test_flow_dissector(void)
{
int i, err, prog_fd, keys_fd = -1, tap_fd;
struct bpf_flow *skel;
skel = bpf_flow__open_and_load();
if (CHECK(!skel, "skel", "failed to open/load skeleton\n"))
return;
prog_fd = bpf_program__fd(skel->progs._dissect);
if (CHECK(prog_fd < 0, "bpf_program__fd", "err %d\n", prog_fd))
goto out_destroy_skel;
keys_fd = bpf_map__fd(skel->maps.last_dissection);
if (CHECK(keys_fd < 0, "bpf_map__fd", "err %d\n", keys_fd))
goto out_destroy_skel;
err = init_prog_array(skel->obj, skel->maps.jmp_table);
if (CHECK(err, "init_prog_array", "err %d\n", err))
goto out_destroy_skel;
for (i = 0; i < ARRAY_SIZE(tests); i++) {
struct bpf_flow_keys flow_keys;
LIBBPF_OPTS(bpf_test_run_opts, topts,
.data_in = &tests[i].pkt,
.data_size_in = sizeof(tests[i].pkt),
.data_out = &flow_keys,
);
static struct bpf_flow_keys ctx = {};
if (tests[i].flags) {
topts.ctx_in = &ctx;
topts.ctx_size_in = sizeof(ctx);
ctx.flags = tests[i].flags;
}
err = bpf_prog_test_run_opts(prog_fd, &topts);
ASSERT_OK(err, "test_run");
ASSERT_EQ(topts.retval, tests[i].retval, "test_run retval");
/* check the resulting flow_keys only if BPF_OK returned */
if (topts.retval != BPF_OK)
continue;
ASSERT_EQ(topts.data_size_out, sizeof(flow_keys),
"test_run data_size_out");
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.
*/
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);
/* Test direct prog attachment */
test_skb_less_prog_attach(skel, tap_fd);
/* Test indirect prog attachment via link */
test_skb_less_link_create(skel, tap_fd);
close(tap_fd);
out_destroy_skel:
bpf_flow__destroy(skel);
}
