diff options
Diffstat (limited to 'tools/bpf/bpftool/net.c')
| -rw-r--r-- | tools/bpf/bpftool/net.c | 230 |
1 files changed, 223 insertions, 7 deletions
diff --git a/tools/bpf/bpftool/net.c b/tools/bpf/bpftool/net.c index db0e7de49d49..4f52d3151616 100644 --- a/tools/bpf/bpftool/net.c +++ b/tools/bpf/bpftool/net.c @@ -3,6 +3,7 @@ #define _GNU_SOURCE #include <errno.h> +#include <fcntl.h> #include <stdlib.h> #include <string.h> #include <unistd.h> @@ -12,6 +13,8 @@ #include <linux/rtnetlink.h> #include <linux/tc_act/tc_bpf.h> #include <sys/socket.h> +#include <sys/stat.h> +#include <sys/types.h> #include <bpf.h> #include <nlattr.h> @@ -48,6 +51,39 @@ struct bpf_filter_t { int ifindex; }; +struct bpf_attach_info { + __u32 flow_dissector_id; +}; + +enum net_attach_type { + NET_ATTACH_TYPE_XDP, + NET_ATTACH_TYPE_XDP_GENERIC, + NET_ATTACH_TYPE_XDP_DRIVER, + NET_ATTACH_TYPE_XDP_OFFLOAD, +}; + +static const char * const attach_type_strings[] = { + [NET_ATTACH_TYPE_XDP] = "xdp", + [NET_ATTACH_TYPE_XDP_GENERIC] = "xdpgeneric", + [NET_ATTACH_TYPE_XDP_DRIVER] = "xdpdrv", + [NET_ATTACH_TYPE_XDP_OFFLOAD] = "xdpoffload", +}; + +const size_t net_attach_type_size = ARRAY_SIZE(attach_type_strings); + +static enum net_attach_type parse_attach_type(const char *str) +{ + enum net_attach_type type; + + for (type = 0; type < net_attach_type_size; type++) { + if (attach_type_strings[type] && + is_prefix(str, attach_type_strings[type])) + return type; + } + + return net_attach_type_size; +} + static int dump_link_nlmsg(void *cookie, void *msg, struct nlattr **tb) { struct bpf_netdev_t *netinfo = cookie; @@ -180,25 +216,190 @@ out: return 0; } +static int query_flow_dissector(struct bpf_attach_info *attach_info) +{ + __u32 attach_flags; + __u32 prog_ids[1]; + __u32 prog_cnt; + int err; + int fd; + + fd = open("/proc/self/ns/net", O_RDONLY); + if (fd < 0) { + p_err("can't open /proc/self/ns/net: %s", + strerror(errno)); + return -1; + } + prog_cnt = ARRAY_SIZE(prog_ids); + err = bpf_prog_query(fd, BPF_FLOW_DISSECTOR, 0, + &attach_flags, prog_ids, &prog_cnt); + close(fd); + if (err) { + if (errno == EINVAL) { + /* Older kernel's don't support querying + * flow dissector programs. + */ + errno = 0; + return 0; + } + p_err("can't query prog: %s", strerror(errno)); + return -1; + } + + if (prog_cnt == 1) + attach_info->flow_dissector_id = prog_ids[0]; + + return 0; +} + +static int net_parse_dev(int *argc, char ***argv) +{ + int ifindex; + + if (is_prefix(**argv, "dev")) { + NEXT_ARGP(); + + ifindex = if_nametoindex(**argv); + if (!ifindex) + p_err("invalid devname %s", **argv); + + NEXT_ARGP(); + } else { + p_err("expected 'dev', got: '%s'?", **argv); + return -1; + } + + return ifindex; +} + +static int do_attach_detach_xdp(int progfd, enum net_attach_type attach_type, + int ifindex, bool overwrite) +{ + __u32 flags = 0; + + if (!overwrite) + flags = XDP_FLAGS_UPDATE_IF_NOEXIST; + if (attach_type == NET_ATTACH_TYPE_XDP_GENERIC) + flags |= XDP_FLAGS_SKB_MODE; + if (attach_type == NET_ATTACH_TYPE_XDP_DRIVER) + flags |= XDP_FLAGS_DRV_MODE; + if (attach_type == NET_ATTACH_TYPE_XDP_OFFLOAD) + flags |= XDP_FLAGS_HW_MODE; + + return bpf_set_link_xdp_fd(ifindex, progfd, flags); +} + +static int do_attach(int argc, char **argv) +{ + enum net_attach_type attach_type; + int progfd, ifindex, err = 0; + bool overwrite = false; + + /* parse attach args */ + if (!REQ_ARGS(5)) + return -EINVAL; + + attach_type = parse_attach_type(*argv); + if (attach_type == net_attach_type_size) { + p_err("invalid net attach/detach type: %s", *argv); + return -EINVAL; + } + NEXT_ARG(); + + progfd = prog_parse_fd(&argc, &argv); + if (progfd < 0) + return -EINVAL; + + ifindex = net_parse_dev(&argc, &argv); + if (ifindex < 1) { + close(progfd); + return -EINVAL; + } + + if (argc) { + if (is_prefix(*argv, "overwrite")) { + overwrite = true; + } else { + p_err("expected 'overwrite', got: '%s'?", *argv); + close(progfd); + return -EINVAL; + } + } + + /* attach xdp prog */ + if (is_prefix("xdp", attach_type_strings[attach_type])) + err = do_attach_detach_xdp(progfd, attach_type, ifindex, + overwrite); + + if (err < 0) { + p_err("interface %s attach failed: %s", + attach_type_strings[attach_type], strerror(-err)); + return err; + } + + if (json_output) + jsonw_null(json_wtr); + + return 0; +} + +static int do_detach(int argc, char **argv) +{ + enum net_attach_type attach_type; + int progfd, ifindex, err = 0; + + /* parse detach args */ + if (!REQ_ARGS(3)) + return -EINVAL; + + attach_type = parse_attach_type(*argv); + if (attach_type == net_attach_type_size) { + p_err("invalid net attach/detach type: %s", *argv); + return -EINVAL; + } + NEXT_ARG(); + + ifindex = net_parse_dev(&argc, &argv); + if (ifindex < 1) + return -EINVAL; + + /* detach xdp prog */ + progfd = -1; + if (is_prefix("xdp", attach_type_strings[attach_type])) + err = do_attach_detach_xdp(progfd, attach_type, ifindex, NULL); + + if (err < 0) { + p_err("interface %s detach failed: %s", + attach_type_strings[attach_type], strerror(-err)); + return err; + } + + if (json_output) + jsonw_null(json_wtr); + + return 0; +} + static int do_show(int argc, char **argv) { + struct bpf_attach_info attach_info = {}; int i, sock, ret, filter_idx = -1; struct bpf_netdev_t dev_array; unsigned int nl_pid; char err_buf[256]; if (argc == 2) { - if (strcmp(argv[0], "dev") != 0) - usage(); - filter_idx = if_nametoindex(argv[1]); - if (filter_idx == 0) { - fprintf(stderr, "invalid dev name %s\n", argv[1]); + filter_idx = net_parse_dev(&argc, &argv); + if (filter_idx < 1) return -1; - } } else if (argc != 0) { usage(); } + ret = query_flow_dissector(&attach_info); + if (ret) + return -1; + sock = libbpf_netlink_open(&nl_pid); if (sock < 0) { fprintf(stderr, "failed to open netlink sock\n"); @@ -227,6 +428,12 @@ static int do_show(int argc, char **argv) } NET_END_ARRAY("\n"); } + + NET_START_ARRAY("flow_dissector", "%s:\n"); + if (attach_info.flow_dissector_id > 0) + NET_DUMP_UINT("id", "id %u", attach_info.flow_dissector_id); + NET_END_ARRAY("\n"); + NET_END_OBJECT; if (json_output) jsonw_end_array(json_wtr); @@ -251,13 +458,20 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %s %s { show | list } [dev <devname>]\n" + " %s %s attach ATTACH_TYPE PROG dev <devname> [ overwrite ]\n" + " %s %s detach ATTACH_TYPE dev <devname>\n" " %s %s help\n" + "\n" + " " HELP_SPEC_PROGRAM "\n" + " ATTACH_TYPE := { xdp | xdpgeneric | xdpdrv | xdpoffload }\n" + "\n" "Note: Only xdp and tc attachments are supported now.\n" " For progs attached to cgroups, use \"bpftool cgroup\"\n" " to dump program attachments. For program types\n" " sk_{filter,skb,msg,reuseport} and lwt/seg6, please\n" " consult iproute2.\n", - bin_name, argv[-2], bin_name, argv[-2]); + bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2], + bin_name, argv[-2]); return 0; } @@ -265,6 +479,8 @@ static int do_help(int argc, char **argv) static const struct cmd cmds[] = { { "show", do_show }, { "list", do_show }, + { "attach", do_attach }, + { "detach", do_detach }, { "help", do_help }, { 0 } }; |
