diff options
Diffstat (limited to 'tools/testing/selftests/bpf/xdp_synproxy.c')
| -rw-r--r-- | tools/testing/selftests/bpf/xdp_synproxy.c | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/xdp_synproxy.c b/tools/testing/selftests/bpf/xdp_synproxy.c new file mode 100644 index 000000000000..ce68c342b56f --- /dev/null +++ b/tools/testing/selftests/bpf/xdp_synproxy.c @@ -0,0 +1,471 @@ +// SPDX-License-Identifier: LGPL-2.1 OR BSD-2-Clause +/* Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved. */ + +#include <stdnoreturn.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <getopt.h> +#include <signal.h> +#include <sys/types.h> +#include <bpf/bpf.h> +#include <bpf/libbpf.h> +#include <net/if.h> +#include <linux/if_link.h> +#include <linux/limits.h> + +static unsigned int ifindex; +static __u32 attached_prog_id; +static bool attached_tc; + +static void noreturn cleanup(int sig) +{ + LIBBPF_OPTS(bpf_xdp_attach_opts, opts); + int prog_fd; + int err; + + if (attached_prog_id == 0) + exit(0); + + if (attached_tc) { + LIBBPF_OPTS(bpf_tc_hook, hook, + .ifindex = ifindex, + .attach_point = BPF_TC_INGRESS); + + err = bpf_tc_hook_destroy(&hook); + if (err < 0) { + fprintf(stderr, "Error: bpf_tc_hook_destroy: %s\n", strerror(-err)); + fprintf(stderr, "Failed to destroy the TC hook\n"); + exit(1); + } + exit(0); + } + + prog_fd = bpf_prog_get_fd_by_id(attached_prog_id); + if (prog_fd < 0) { + fprintf(stderr, "Error: bpf_prog_get_fd_by_id: %s\n", strerror(-prog_fd)); + err = bpf_xdp_attach(ifindex, -1, 0, NULL); + if (err < 0) { + fprintf(stderr, "Error: bpf_set_link_xdp_fd: %s\n", strerror(-err)); + fprintf(stderr, "Failed to detach XDP program\n"); + exit(1); + } + } else { + opts.old_prog_fd = prog_fd; + err = bpf_xdp_attach(ifindex, -1, XDP_FLAGS_REPLACE, &opts); + close(prog_fd); + if (err < 0) { + fprintf(stderr, "Error: bpf_set_link_xdp_fd_opts: %s\n", strerror(-err)); + /* Not an error if already replaced by someone else. */ + if (err != -EEXIST) { + fprintf(stderr, "Failed to detach XDP program\n"); + exit(1); + } + } + } + exit(0); +} + +static noreturn void usage(const char *progname) +{ + fprintf(stderr, "Usage: %s [--iface <iface>|--prog <prog_id>] [--mss4 <mss ipv4> --mss6 <mss ipv6> --wscale <wscale> --ttl <ttl>] [--ports <port1>,<port2>,...] [--single] [--tc]\n", + progname); + exit(1); +} + +static unsigned long parse_arg_ul(const char *progname, const char *arg, unsigned long limit) +{ + unsigned long res; + char *endptr; + + errno = 0; + res = strtoul(arg, &endptr, 10); + if (errno != 0 || *endptr != '\0' || arg[0] == '\0' || res > limit) + usage(progname); + + return res; +} + +static void parse_options(int argc, char *argv[], unsigned int *ifindex, __u32 *prog_id, + __u64 *tcpipopts, char **ports, bool *single, bool *tc) +{ + static struct option long_options[] = { + { "help", no_argument, NULL, 'h' }, + { "iface", required_argument, NULL, 'i' }, + { "prog", required_argument, NULL, 'x' }, + { "mss4", required_argument, NULL, 4 }, + { "mss6", required_argument, NULL, 6 }, + { "wscale", required_argument, NULL, 'w' }, + { "ttl", required_argument, NULL, 't' }, + { "ports", required_argument, NULL, 'p' }, + { "single", no_argument, NULL, 's' }, + { "tc", no_argument, NULL, 'c' }, + { NULL, 0, NULL, 0 }, + }; + unsigned long mss4, wscale, ttl; + unsigned long long mss6; + unsigned int tcpipopts_mask = 0; + + if (argc < 2) + usage(argv[0]); + + *ifindex = 0; + *prog_id = 0; + *tcpipopts = 0; + *ports = NULL; + *single = false; + *tc = false; + + while (true) { + int opt; + + opt = getopt_long(argc, argv, "", long_options, NULL); + if (opt == -1) + break; + + switch (opt) { + case 'h': + usage(argv[0]); + break; + case 'i': + *ifindex = if_nametoindex(optarg); + if (*ifindex == 0) + usage(argv[0]); + break; + case 'x': + *prog_id = parse_arg_ul(argv[0], optarg, UINT32_MAX); + if (*prog_id == 0) + usage(argv[0]); + break; + case 4: + mss4 = parse_arg_ul(argv[0], optarg, UINT16_MAX); + tcpipopts_mask |= 1 << 0; + break; + case 6: + mss6 = parse_arg_ul(argv[0], optarg, UINT16_MAX); + tcpipopts_mask |= 1 << 1; + break; + case 'w': + wscale = parse_arg_ul(argv[0], optarg, 14); + tcpipopts_mask |= 1 << 2; + break; + case 't': + ttl = parse_arg_ul(argv[0], optarg, UINT8_MAX); + tcpipopts_mask |= 1 << 3; + break; + case 'p': + *ports = optarg; + break; + case 's': + *single = true; + break; + case 'c': + *tc = true; + break; + default: + usage(argv[0]); + } + } + if (optind < argc) + usage(argv[0]); + + if (tcpipopts_mask == 0xf) { + if (mss4 == 0 || mss6 == 0 || wscale == 0 || ttl == 0) + usage(argv[0]); + *tcpipopts = (mss6 << 32) | (ttl << 24) | (wscale << 16) | mss4; + } else if (tcpipopts_mask != 0) { + usage(argv[0]); + } + + if (*ifindex != 0 && *prog_id != 0) + usage(argv[0]); + if (*ifindex == 0 && *prog_id == 0) + usage(argv[0]); +} + +static int syncookie_attach(const char *argv0, unsigned int ifindex, bool tc) +{ + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); + char xdp_filename[PATH_MAX]; + struct bpf_program *prog; + struct bpf_object *obj; + int prog_fd; + int err; + + snprintf(xdp_filename, sizeof(xdp_filename), "%s_kern.bpf.o", argv0); + obj = bpf_object__open_file(xdp_filename, NULL); + err = libbpf_get_error(obj); + if (err < 0) { + fprintf(stderr, "Error: bpf_object__open_file: %s\n", strerror(-err)); + return err; + } + + err = bpf_object__load(obj); + if (err < 0) { + fprintf(stderr, "Error: bpf_object__open_file: %s\n", strerror(-err)); + return err; + } + + prog = bpf_object__find_program_by_name(obj, tc ? "syncookie_tc" : "syncookie_xdp"); + if (!prog) { + fprintf(stderr, "Error: bpf_object__find_program_by_name: program was not found\n"); + return -ENOENT; + } + + prog_fd = bpf_program__fd(prog); + + err = bpf_prog_get_info_by_fd(prog_fd, &info, &info_len); + if (err < 0) { + fprintf(stderr, "Error: bpf_prog_get_info_by_fd: %s\n", + strerror(-err)); + goto out; + } + attached_tc = tc; + attached_prog_id = info.id; + signal(SIGINT, cleanup); + signal(SIGTERM, cleanup); + if (tc) { + LIBBPF_OPTS(bpf_tc_hook, hook, + .ifindex = ifindex, + .attach_point = BPF_TC_INGRESS); + LIBBPF_OPTS(bpf_tc_opts, opts, + .handle = 1, + .priority = 1, + .prog_fd = prog_fd); + + err = bpf_tc_hook_create(&hook); + if (err < 0) { + fprintf(stderr, "Error: bpf_tc_hook_create: %s\n", + strerror(-err)); + goto fail; + } + err = bpf_tc_attach(&hook, &opts); + if (err < 0) { + fprintf(stderr, "Error: bpf_tc_attach: %s\n", + strerror(-err)); + goto fail; + } + + } else { + err = bpf_xdp_attach(ifindex, prog_fd, + XDP_FLAGS_UPDATE_IF_NOEXIST, NULL); + if (err < 0) { + fprintf(stderr, "Error: bpf_set_link_xdp_fd: %s\n", + strerror(-err)); + goto fail; + } + } + err = 0; +out: + bpf_object__close(obj); + return err; +fail: + signal(SIGINT, SIG_DFL); + signal(SIGTERM, SIG_DFL); + attached_prog_id = 0; + goto out; +} + +static int syncookie_open_bpf_maps(__u32 prog_id, int *values_map_fd, int *ports_map_fd) +{ + struct bpf_prog_info prog_info; + __u32 map_ids[8]; + __u32 info_len; + int prog_fd; + int err; + int i; + + *values_map_fd = -1; + *ports_map_fd = -1; + + prog_fd = bpf_prog_get_fd_by_id(prog_id); + if (prog_fd < 0) { + fprintf(stderr, "Error: bpf_prog_get_fd_by_id: %s\n", strerror(-prog_fd)); + return prog_fd; + } + + prog_info = (struct bpf_prog_info) { + .nr_map_ids = 8, + .map_ids = (__u64)(unsigned long)map_ids, + }; + info_len = sizeof(prog_info); + + err = bpf_prog_get_info_by_fd(prog_fd, &prog_info, &info_len); + if (err != 0) { + fprintf(stderr, "Error: bpf_prog_get_info_by_fd: %s\n", + strerror(-err)); + goto out; + } + + if (prog_info.nr_map_ids < 2) { + fprintf(stderr, "Error: Found %u BPF maps, expected at least 2\n", + prog_info.nr_map_ids); + err = -ENOENT; + goto out; + } + + for (i = 0; i < prog_info.nr_map_ids; i++) { + struct bpf_map_info map_info = {}; + int map_fd; + + err = bpf_map_get_fd_by_id(map_ids[i]); + if (err < 0) { + fprintf(stderr, "Error: bpf_map_get_fd_by_id: %s\n", strerror(-err)); + goto err_close_map_fds; + } + map_fd = err; + + info_len = sizeof(map_info); + err = bpf_map_get_info_by_fd(map_fd, &map_info, &info_len); + if (err != 0) { + fprintf(stderr, "Error: bpf_map_get_info_by_fd: %s\n", + strerror(-err)); + close(map_fd); + goto err_close_map_fds; + } + if (strcmp(map_info.name, "values") == 0) { + *values_map_fd = map_fd; + continue; + } + if (strcmp(map_info.name, "allowed_ports") == 0) { + *ports_map_fd = map_fd; + continue; + } + close(map_fd); + } + + if (*values_map_fd != -1 && *ports_map_fd != -1) { + err = 0; + goto out; + } + + err = -ENOENT; + +err_close_map_fds: + if (*values_map_fd != -1) + close(*values_map_fd); + if (*ports_map_fd != -1) + close(*ports_map_fd); + *values_map_fd = -1; + *ports_map_fd = -1; + +out: + close(prog_fd); + return err; +} + +int main(int argc, char *argv[]) +{ + int values_map_fd, ports_map_fd; + __u64 tcpipopts; + bool firstiter; + __u64 prevcnt; + __u32 prog_id; + char *ports; + bool single; + int err = 0; + bool tc; + + parse_options(argc, argv, &ifindex, &prog_id, &tcpipopts, &ports, + &single, &tc); + + if (prog_id == 0) { + if (!tc) { + err = bpf_xdp_query_id(ifindex, 0, &prog_id); + if (err < 0) { + fprintf(stderr, "Error: bpf_get_link_xdp_id: %s\n", + strerror(-err)); + goto out; + } + } + if (prog_id == 0) { + err = syncookie_attach(argv[0], ifindex, tc); + if (err < 0) + goto out; + prog_id = attached_prog_id; + } + } + + err = syncookie_open_bpf_maps(prog_id, &values_map_fd, &ports_map_fd); + if (err < 0) + goto out; + + if (ports) { + __u16 port_last = 0; + __u32 port_idx = 0; + char *p = ports; + + fprintf(stderr, "Replacing allowed ports\n"); + + while (p && *p != '\0') { + char *token = strsep(&p, ","); + __u16 port; + + port = parse_arg_ul(argv[0], token, UINT16_MAX); + err = bpf_map_update_elem(ports_map_fd, &port_idx, &port, BPF_ANY); + if (err != 0) { + fprintf(stderr, "Error: bpf_map_update_elem: %s\n", strerror(-err)); + fprintf(stderr, "Failed to add port %u (index %u)\n", + port, port_idx); + goto out_close_maps; + } + fprintf(stderr, "Added port %u\n", port); + port_idx++; + } + err = bpf_map_update_elem(ports_map_fd, &port_idx, &port_last, BPF_ANY); + if (err != 0) { + fprintf(stderr, "Error: bpf_map_update_elem: %s\n", strerror(-err)); + fprintf(stderr, "Failed to add the terminator value 0 (index %u)\n", + port_idx); + goto out_close_maps; + } + } + + if (tcpipopts) { + __u32 key = 0; + + fprintf(stderr, "Replacing TCP/IP options\n"); + + err = bpf_map_update_elem(values_map_fd, &key, &tcpipopts, BPF_ANY); + if (err != 0) { + fprintf(stderr, "Error: bpf_map_update_elem: %s\n", strerror(-err)); + goto out_close_maps; + } + } + + if ((ports || tcpipopts) && attached_prog_id == 0 && !single) + goto out_close_maps; + + prevcnt = 0; + firstiter = true; + while (true) { + __u32 key = 1; + __u64 value; + + err = bpf_map_lookup_elem(values_map_fd, &key, &value); + if (err != 0) { + fprintf(stderr, "Error: bpf_map_lookup_elem: %s\n", strerror(-err)); + goto out_close_maps; + } + if (firstiter) { + prevcnt = value; + firstiter = false; + } + if (single) { + printf("Total SYNACKs generated: %llu\n", value); + break; + } + printf("SYNACKs generated: %llu (total %llu)\n", value - prevcnt, value); + prevcnt = value; + sleep(1); + } + +out_close_maps: + close(values_map_fd); + close(ports_map_fd); +out: + return err == 0 ? 0 : 1; +} |