diff options
Diffstat (limited to 'tools/bpf/bpftool/feature.c')
| -rw-r--r-- | tools/bpf/bpftool/feature.c | 312 |
1 files changed, 266 insertions, 46 deletions
diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c index e999159fa28d..36cf0f1517c9 100644 --- a/tools/bpf/bpftool/feature.c +++ b/tools/bpf/bpftool/feature.c @@ -3,6 +3,7 @@ #include <ctype.h> #include <errno.h> +#include <fcntl.h> #include <string.h> #include <unistd.h> #include <net/if.h> @@ -45,6 +46,11 @@ static bool run_as_unprivileged; /* Miscellaneous utility functions */ +static bool grep(const char *buffer, const char *pattern) +{ + return !!strstr(buffer, pattern); +} + static bool check_procfs(void) { struct statfs st_fs; @@ -135,6 +141,32 @@ static void print_end_section(void) /* Probing functions */ +static int get_vendor_id(int ifindex) +{ + char ifname[IF_NAMESIZE], path[64], buf[8]; + ssize_t len; + int fd; + + if (!if_indextoname(ifindex, ifname)) + return -1; + + snprintf(path, sizeof(path), "/sys/class/net/%s/device/vendor", ifname); + + fd = open(path, O_RDONLY | O_CLOEXEC); + if (fd < 0) + return -1; + + len = read(fd, buf, sizeof(buf)); + close(fd); + if (len < 0) + return -1; + if (len >= (ssize_t)sizeof(buf)) + return -1; + buf[len] = '\0'; + + return strtol(buf, NULL, 0); +} + static int read_procfs(const char *path) { char *endptr, *line = NULL; @@ -175,7 +207,10 @@ static void probe_unprivileged_disabled(void) printf("bpf() syscall for unprivileged users is enabled\n"); break; case 1: - printf("bpf() syscall restricted to privileged users\n"); + printf("bpf() syscall restricted to privileged users (without recovery)\n"); + break; + case 2: + printf("bpf() syscall restricted to privileged users (admin can change)\n"); break; case -1: printf("Unable to retrieve required privileges for bpf() syscall\n"); @@ -478,17 +513,50 @@ static bool probe_bpf_syscall(const char *define_prefix) return res; } +static bool +probe_prog_load_ifindex(enum bpf_prog_type prog_type, + const struct bpf_insn *insns, size_t insns_cnt, + char *log_buf, size_t log_buf_sz, + __u32 ifindex) +{ + LIBBPF_OPTS(bpf_prog_load_opts, opts, + .log_buf = log_buf, + .log_size = log_buf_sz, + .log_level = log_buf ? 1 : 0, + .prog_ifindex = ifindex, + ); + int fd; + + errno = 0; + fd = bpf_prog_load(prog_type, NULL, "GPL", insns, insns_cnt, &opts); + if (fd >= 0) + close(fd); + + return fd >= 0 && errno != EINVAL && errno != EOPNOTSUPP; +} + +static bool probe_prog_type_ifindex(enum bpf_prog_type prog_type, __u32 ifindex) +{ + /* nfp returns -EINVAL on exit(0) with TC offload */ + struct bpf_insn insns[2] = { + BPF_MOV64_IMM(BPF_REG_0, 2), + BPF_EXIT_INSN() + }; + + return probe_prog_load_ifindex(prog_type, insns, ARRAY_SIZE(insns), + NULL, 0, ifindex); +} + static void -probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, - const char *define_prefix, __u32 ifindex) +probe_prog_type(enum bpf_prog_type prog_type, const char *prog_type_str, + bool *supported_types, const char *define_prefix, __u32 ifindex) { char feat_name[128], plain_desc[128], define_name[128]; const char *plain_comment = "eBPF program_type "; size_t maxlen; bool res; - if (ifindex) - /* Only test offload-able program types */ + if (ifindex) { switch (prog_type) { case BPF_PROG_TYPE_SCHED_CLS: case BPF_PROG_TYPE_XDP: @@ -497,7 +565,11 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, return; } - res = bpf_probe_prog_type(prog_type, ifindex); + res = probe_prog_type_ifindex(prog_type, ifindex); + } else { + res = libbpf_probe_bpf_prog_type(prog_type, NULL) > 0; + } + #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for unprivileged users * check that we did not fail because of insufficient permissions @@ -508,58 +580,109 @@ probe_prog_type(enum bpf_prog_type prog_type, bool *supported_types, supported_types[prog_type] |= res; - if (!prog_type_name[prog_type]) { - p_info("program type name not found (type %d)", prog_type); - return; - } maxlen = sizeof(plain_desc) - strlen(plain_comment) - 1; - if (strlen(prog_type_name[prog_type]) > maxlen) { + if (strlen(prog_type_str) > maxlen) { p_info("program type name too long"); return; } - sprintf(feat_name, "have_%s_prog_type", prog_type_name[prog_type]); - sprintf(define_name, "%s_prog_type", prog_type_name[prog_type]); + sprintf(feat_name, "have_%s_prog_type", prog_type_str); + sprintf(define_name, "%s_prog_type", prog_type_str); uppercase(define_name, sizeof(define_name)); - sprintf(plain_desc, "%s%s", plain_comment, prog_type_name[prog_type]); + sprintf(plain_desc, "%s%s", plain_comment, prog_type_str); print_bool_feature(feat_name, plain_desc, define_name, res, define_prefix); } +static bool probe_map_type_ifindex(enum bpf_map_type map_type, __u32 ifindex) +{ + LIBBPF_OPTS(bpf_map_create_opts, opts); + int key_size, value_size, max_entries; + int fd; + + opts.map_ifindex = ifindex; + + key_size = sizeof(__u32); + value_size = sizeof(__u32); + max_entries = 1; + + fd = bpf_map_create(map_type, NULL, key_size, value_size, max_entries, + &opts); + if (fd >= 0) + close(fd); + + return fd >= 0; +} + static void -probe_map_type(enum bpf_map_type map_type, const char *define_prefix, - __u32 ifindex) +probe_map_type(enum bpf_map_type map_type, char const *map_type_str, + const char *define_prefix, __u32 ifindex) { char feat_name[128], plain_desc[128], define_name[128]; const char *plain_comment = "eBPF map_type "; size_t maxlen; bool res; - res = bpf_probe_map_type(map_type, ifindex); + if (ifindex) { + switch (map_type) { + case BPF_MAP_TYPE_HASH: + case BPF_MAP_TYPE_ARRAY: + break; + default: + return; + } + + res = probe_map_type_ifindex(map_type, ifindex); + } else { + res = libbpf_probe_bpf_map_type(map_type, NULL) > 0; + } /* Probe result depends on the success of map creation, no additional * check required for unprivileged users */ - if (!map_type_name[map_type]) { - p_info("map type name not found (type %d)", map_type); - return; - } maxlen = sizeof(plain_desc) - strlen(plain_comment) - 1; - if (strlen(map_type_name[map_type]) > maxlen) { + if (strlen(map_type_str) > maxlen) { p_info("map type name too long"); return; } - sprintf(feat_name, "have_%s_map_type", map_type_name[map_type]); - sprintf(define_name, "%s_map_type", map_type_name[map_type]); + sprintf(feat_name, "have_%s_map_type", map_type_str); + sprintf(define_name, "%s_map_type", map_type_str); uppercase(define_name, sizeof(define_name)); - sprintf(plain_desc, "%s%s", plain_comment, map_type_name[map_type]); + sprintf(plain_desc, "%s%s", plain_comment, map_type_str); print_bool_feature(feat_name, plain_desc, define_name, res, define_prefix); } -static void +static bool +probe_helper_ifindex(enum bpf_func_id id, enum bpf_prog_type prog_type, + __u32 ifindex) +{ + struct bpf_insn insns[2] = { + BPF_EMIT_CALL(id), + BPF_EXIT_INSN() + }; + char buf[4096] = {}; + bool res; + + probe_prog_load_ifindex(prog_type, insns, ARRAY_SIZE(insns), buf, + sizeof(buf), ifindex); + res = !grep(buf, "invalid func ") && !grep(buf, "unknown func "); + + switch (get_vendor_id(ifindex)) { + case 0x19ee: /* Netronome specific */ + res = res && !grep(buf, "not supported by FW") && + !grep(buf, "unsupported function id"); + break; + default: + break; + } + + return res; +} + +static bool probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, const char *define_prefix, unsigned int id, const char *ptype_name, __u32 ifindex) @@ -567,7 +690,10 @@ probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, bool res = false; if (supported_type) { - res = bpf_probe_helper(id, prog_type, ifindex); + if (ifindex) + res = probe_helper_ifindex(id, prog_type, ifindex); + else + res = libbpf_probe_bpf_helper(prog_type, id, NULL) > 0; #ifdef USE_LIBCAP /* Probe may succeed even if program load fails, for * unprivileged users check that we did not fail because of @@ -589,15 +715,18 @@ probe_helper_for_progtype(enum bpf_prog_type prog_type, bool supported_type, if (res) printf("\n\t- %s", helper_name[id]); } + + return res; } static void -probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, +probe_helpers_for_progtype(enum bpf_prog_type prog_type, + const char *prog_type_str, bool supported_type, const char *define_prefix, __u32 ifindex) { - const char *ptype_name = prog_type_name[prog_type]; char feat_name[128]; unsigned int id; + bool probe_res = false; if (ifindex) /* Only test helpers for offload-able program types */ @@ -610,12 +739,12 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, } if (json_output) { - sprintf(feat_name, "%s_available_helpers", ptype_name); + sprintf(feat_name, "%s_available_helpers", prog_type_str); jsonw_name(json_wtr, feat_name); jsonw_start_array(json_wtr); } else if (!define_prefix) { printf("eBPF helpers supported for program type %s:", - ptype_name); + prog_type_str); } for (id = 1; id < ARRAY_SIZE(helper_name); id++) { @@ -630,16 +759,25 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type, continue; /* fallthrough */ default: - probe_helper_for_progtype(prog_type, supported_type, - define_prefix, id, ptype_name, + probe_res |= probe_helper_for_progtype(prog_type, supported_type, + define_prefix, id, prog_type_str, ifindex); } } if (json_output) jsonw_end_array(json_wtr); - else if (!define_prefix) + else if (!define_prefix) { printf("\n"); + if (!probe_res) { + if (!supported_type) + printf("\tProgram type not supported\n"); + else + printf("\tCould not determine which helpers are available\n"); + } + } + + } static void @@ -797,30 +935,47 @@ static void section_program_types(bool *supported_types, const char *define_prefix, __u32 ifindex) { - unsigned int i; + unsigned int prog_type = BPF_PROG_TYPE_UNSPEC; + const char *prog_type_str; print_start_section("program_types", "Scanning eBPF program types...", "/*** eBPF program types ***/", define_prefix); - for (i = BPF_PROG_TYPE_UNSPEC + 1; i < prog_type_name_size; i++) - probe_prog_type(i, supported_types, define_prefix, ifindex); + while (true) { + prog_type++; + prog_type_str = libbpf_bpf_prog_type_str(prog_type); + /* libbpf will return NULL for variants unknown to it. */ + if (!prog_type_str) + break; + + probe_prog_type(prog_type, prog_type_str, supported_types, define_prefix, + ifindex); + } print_end_section(); } static void section_map_types(const char *define_prefix, __u32 ifindex) { - unsigned int i; + unsigned int map_type = BPF_MAP_TYPE_UNSPEC; + const char *map_type_str; print_start_section("map_types", "Scanning eBPF map types...", "/*** eBPF map types ***/", define_prefix); - for (i = BPF_MAP_TYPE_UNSPEC + 1; i < map_type_name_size; i++) - probe_map_type(i, define_prefix, ifindex); + while (true) { + map_type++; + map_type_str = libbpf_bpf_map_type_str(map_type); + /* libbpf will return NULL for variants unknown to it. */ + if (!map_type_str) + break; + + probe_map_type(map_type, map_type_str, define_prefix, ifindex); + } print_end_section(); } @@ -828,7 +983,8 @@ static void section_map_types(const char *define_prefix, __u32 ifindex) static void section_helpers(bool *supported_types, const char *define_prefix, __u32 ifindex) { - unsigned int i; + unsigned int prog_type = BPF_PROG_TYPE_UNSPEC; + const char *prog_type_str; print_start_section("helpers", "Scanning eBPF helper functions...", @@ -850,9 +1006,18 @@ section_helpers(bool *supported_types, const char *define_prefix, __u32 ifindex) " %sBPF__PROG_TYPE_ ## prog_type ## __HELPER_ ## helper\n", define_prefix, define_prefix, define_prefix, define_prefix); - for (i = BPF_PROG_TYPE_UNSPEC + 1; i < prog_type_name_size; i++) - probe_helpers_for_progtype(i, supported_types[i], define_prefix, + while (true) { + prog_type++; + prog_type_str = libbpf_bpf_prog_type_str(prog_type); + /* libbpf will return NULL for variants unknown to it. */ + if (!prog_type_str) + break; + + probe_helpers_for_progtype(prog_type, prog_type_str, + supported_types[prog_type], + define_prefix, ifindex); + } print_end_section(); } @@ -982,7 +1147,7 @@ exit_free: return res; #else /* Detection assumes user has specific privileges. - * We do not use libpcap so let's approximate, and restrict usage to + * We do not use libcap so let's approximate, and restrict usage to * root user only. */ if (geteuid()) { @@ -1093,6 +1258,58 @@ exit_close_json: return 0; } +static const char *get_helper_name(unsigned int id) +{ + if (id >= ARRAY_SIZE(helper_name)) + return NULL; + + return helper_name[id]; +} + +static int do_list_builtins(int argc, char **argv) +{ + const char *(*get_name)(unsigned int id); + unsigned int id = 0; + + if (argc < 1) + usage(); + + if (is_prefix(*argv, "prog_types")) { + get_name = (const char *(*)(unsigned int))libbpf_bpf_prog_type_str; + } else if (is_prefix(*argv, "map_types")) { + get_name = (const char *(*)(unsigned int))libbpf_bpf_map_type_str; + } else if (is_prefix(*argv, "attach_types")) { + get_name = (const char *(*)(unsigned int))libbpf_bpf_attach_type_str; + } else if (is_prefix(*argv, "link_types")) { + get_name = (const char *(*)(unsigned int))libbpf_bpf_link_type_str; + } else if (is_prefix(*argv, "helpers")) { + get_name = get_helper_name; + } else { + p_err("expected 'prog_types', 'map_types', 'attach_types', 'link_types' or 'helpers', got: %s", *argv); + return -1; + } + + if (json_output) + jsonw_start_array(json_wtr); /* root array */ + + while (true) { + const char *name; + + name = get_name(id++); + if (!name) + break; + if (json_output) + jsonw_string(json_wtr, name); + else + printf("%s\n", name); + } + + if (json_output) + jsonw_end_array(json_wtr); /* root array */ + + return 0; +} + static int do_help(int argc, char **argv) { if (json_output) { @@ -1102,9 +1319,11 @@ static int do_help(int argc, char **argv) fprintf(stderr, "Usage: %1$s %2$s probe [COMPONENT] [full] [unprivileged] [macros [prefix PREFIX]]\n" + " %1$s %2$s list_builtins GROUP\n" " %1$s %2$s help\n" "\n" " COMPONENT := { kernel | dev NAME }\n" + " GROUP := { prog_types | map_types | attach_types | link_types | helpers }\n" " " HELP_SPEC_OPTIONS " }\n" "", bin_name, argv[-2]); @@ -1113,8 +1332,9 @@ static int do_help(int argc, char **argv) } static const struct cmd cmds[] = { - { "probe", do_probe }, - { "help", do_help }, + { "probe", do_probe }, + { "list_builtins", do_list_builtins }, + { "help", do_help }, { 0 } }; |