tools: bpf: add bpftool

Add a simple tool for querying and updating BPF objects on the system.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 744 insertions, 0 deletions

diff --git a/tools/bpf/bpftool/map.c b/tools/bpf/bpftool/map.c
new file mode 100644
index 000000000000..0528a5379e6c
--- /dev/null
+++ b/tools/bpf/bpftool/map.c
@@ -0,0 +1,744 @@
+/*
+ * Copyright (C) 2017 Netronome Systems, Inc.
+ *
+ * This software is dual licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree or the BSD 2-Clause License provided below.  You have the
+ * option to license this software under the complete terms of either license.
+ *
+ * The BSD 2-Clause License:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      1. Redistributions of source code must retain the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer.
+ *
+ *      2. Redistributions in binary form must reproduce the above
+ *         copyright notice, this list of conditions and the following
+ *         disclaimer in the documentation and/or other materials
+ *         provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+/* Author: Jakub Kicinski <kubakici@wp.pl> */
+
+#include <assert.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <bpf.h>
+
+#include "main.h"
+
+static const char * const map_type_name[] = {
+	[BPF_MAP_TYPE_UNSPEC]		= "unspec",
+	[BPF_MAP_TYPE_HASH]		= "hash",
+	[BPF_MAP_TYPE_ARRAY]		= "array",
+	[BPF_MAP_TYPE_PROG_ARRAY]	= "prog_array",
+	[BPF_MAP_TYPE_PERF_EVENT_ARRAY]	= "perf_event_array",
+	[BPF_MAP_TYPE_PERCPU_HASH]	= "percpu_hash",
+	[BPF_MAP_TYPE_PERCPU_ARRAY]	= "percpu_array",
+	[BPF_MAP_TYPE_STACK_TRACE]	= "stack_trace",
+	[BPF_MAP_TYPE_CGROUP_ARRAY]	= "cgroup_array",
+	[BPF_MAP_TYPE_LRU_HASH]		= "lru_hash",
+	[BPF_MAP_TYPE_LRU_PERCPU_HASH]	= "lru_percpu_hash",
+	[BPF_MAP_TYPE_LPM_TRIE]		= "lpm_trie",
+	[BPF_MAP_TYPE_ARRAY_OF_MAPS]	= "array_of_maps",
+	[BPF_MAP_TYPE_HASH_OF_MAPS]	= "hash_of_maps",
+	[BPF_MAP_TYPE_DEVMAP]		= "devmap",
+	[BPF_MAP_TYPE_SOCKMAP]		= "sockmap",
+};
+
+static unsigned int get_possible_cpus(void)
+{
+	static unsigned int result;
+	char buf[128];
+	long int n;
+	char *ptr;
+	int fd;
+
+	if (result)
+		return result;
+
+	fd = open("/sys/devices/system/cpu/possible", O_RDONLY);
+	if (fd < 0) {
+		err("can't open sysfs possible cpus\n");
+		exit(-1);
+	}
+
+	n = read(fd, buf, sizeof(buf));
+	if (n < 2) {
+		err("can't read sysfs possible cpus\n");
+		exit(-1);
+	}
+	close(fd);
+
+	if (n == sizeof(buf)) {
+		err("read sysfs possible cpus overflow\n");
+		exit(-1);
+	}
+
+	ptr = buf;
+	n = 0;
+	while (*ptr && *ptr != '\n') {
+		unsigned int a, b;
+
+		if (sscanf(ptr, "%u-%u", &a, &b) == 2) {
+			n += b - a + 1;
+
+			ptr = strchr(ptr, '-') + 1;
+		} else if (sscanf(ptr, "%u", &a) == 1) {
+			n++;
+		} else {
+			assert(0);
+		}
+
+		while (isdigit(*ptr))
+			ptr++;
+		if (*ptr == ',')
+			ptr++;
+	}
+
+	result = n;
+
+	return result;
+}
+
+static bool map_is_per_cpu(__u32 type)
+{
+	return type == BPF_MAP_TYPE_PERCPU_HASH ||
+	       type == BPF_MAP_TYPE_PERCPU_ARRAY ||
+	       type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
+}
+
+static bool map_is_map_of_maps(__u32 type)
+{
+	return type == BPF_MAP_TYPE_ARRAY_OF_MAPS ||
+	       type == BPF_MAP_TYPE_HASH_OF_MAPS;
+}
+
+static bool map_is_map_of_progs(__u32 type)
+{
+	return type == BPF_MAP_TYPE_PROG_ARRAY;
+}
+
+static void *alloc_value(struct bpf_map_info *info)
+{
+	if (map_is_per_cpu(info->type))
+		return malloc(info->value_size * get_possible_cpus());
+	else
+		return malloc(info->value_size);
+}
+
+static int map_parse_fd(int *argc, char ***argv)
+{
+	int fd;
+
+	if (is_prefix(**argv, "id")) {
+		unsigned int id;
+		char *endptr;
+
+		NEXT_ARGP();
+
+		id = strtoul(**argv, &endptr, 0);
+		if (*endptr) {
+			err("can't parse %s as ID\n", **argv);
+			return -1;
+		}
+		NEXT_ARGP();
+
+		fd = bpf_map_get_fd_by_id(id);
+		if (fd < 0)
+			err("get map by id (%u): %s\n", id, strerror(errno));
+		return fd;
+	} else if (is_prefix(**argv, "pinned")) {
+		char *path;
+
+		NEXT_ARGP();
+
+		path = **argv;
+		NEXT_ARGP();
+
+		return open_obj_pinned_any(path, BPF_OBJ_MAP);
+	}
+
+	err("expected 'id' or 'pinned', got: '%s'?\n", **argv);
+	return -1;
+}
+
+static int
+map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
+{
+	int err;
+	int fd;
+
+	fd = map_parse_fd(argc, argv);
+	if (fd < 0)
+		return -1;
+
+	err = bpf_obj_get_info_by_fd(fd, info, info_len);
+	if (err) {
+		err("can't get map info: %s\n", strerror(errno));
+		close(fd);
+		return err;
+	}
+
+	return fd;
+}
+
+static void print_entry(struct bpf_map_info *info, unsigned char *key,
+			unsigned char *value)
+{
+	if (!map_is_per_cpu(info->type)) {
+		bool single_line, break_names;
+
+		break_names = info->key_size > 16 || info->value_size > 16;
+		single_line = info->key_size + info->value_size <= 24 &&
+			!break_names;
+
+		printf("key:%c", break_names ? '\n' : ' ');
+		print_hex(key, info->key_size, " ");
+
+		printf(single_line ? "  " : "\n");
+
+		printf("value:%c", break_names ? '\n' : ' ');
+		print_hex(value, info->value_size, " ");
+
+		printf("\n");
+	} else {
+		unsigned int i, n;
+
+		n = get_possible_cpus();
+
+		printf("key:\n");
+		print_hex(key, info->key_size, " ");
+		printf("\n");
+		for (i = 0; i < n; i++) {
+			printf("value (CPU %02d):%c",
+			       i, info->value_size > 16 ? '\n' : ' ');
+			print_hex(value + i * info->value_size,
+				  info->value_size, " ");
+			printf("\n");
+		}
+	}
+}
+
+static char **parse_bytes(char **argv, const char *name, unsigned char *val,
+			  unsigned int n)
+{
+	unsigned int i = 0;
+	char *endptr;
+
+	while (i < n && argv[i]) {
+		val[i] = strtoul(argv[i], &endptr, 0);
+		if (*endptr) {
+			err("error parsing byte: %s\n", argv[i]);
+			break;
+		}
+		i++;
+	}
+
+	if (i != n) {
+		err("%s expected %d bytes got %d\n", name, n, i);
+		return NULL;
+	}
+
+	return argv + i;
+}
+
+static int parse_elem(char **argv, struct bpf_map_info *info,
+		      void *key, void *value, __u32 key_size, __u32 value_size,
+		      __u32 *flags, __u32 **value_fd)
+{
+	if (!*argv) {
+		if (!key && !value)
+			return 0;
+		err("did not find %s\n", key ? "key" : "value");
+		return -1;
+	}
+
+	if (is_prefix(*argv, "key")) {
+		if (!key) {
+			if (key_size)
+				err("duplicate key\n");
+			else
+				err("unnecessary key\n");
+			return -1;
+		}
+
+		argv = parse_bytes(argv + 1, "key", key, key_size);
+		if (!argv)
+			return -1;
+
+		return parse_elem(argv, info, NULL, value, key_size, value_size,
+				  flags, value_fd);
+	} else if (is_prefix(*argv, "value")) {
+		int fd;
+
+		if (!value) {
+			if (value_size)
+				err("duplicate value\n");
+			else
+				err("unnecessary value\n");
+			return -1;
+		}
+
+		argv++;
+
+		if (map_is_map_of_maps(info->type)) {
+			int argc = 2;
+
+			if (value_size != 4) {
+				err("value smaller than 4B for map in map?\n");
+				return -1;
+			}
+			if (!argv[0] || !argv[1]) {
+				err("not enough value arguments for map in map\n");
+				return -1;
+			}
+
+			fd = map_parse_fd(&argc, &argv);
+			if (fd < 0)
+				return -1;
+
+			*value_fd = value;
+			**value_fd = fd;
+		} else if (map_is_map_of_progs(info->type)) {
+			int argc = 2;
+
+			if (value_size != 4) {
+				err("value smaller than 4B for map of progs?\n");
+				return -1;
+			}
+			if (!argv[0] || !argv[1]) {
+				err("not enough value arguments for map of progs\n");
+				return -1;
+			}
+
+			fd = prog_parse_fd(&argc, &argv);
+			if (fd < 0)
+				return -1;
+
+			*value_fd = value;
+			**value_fd = fd;
+		} else {
+			argv = parse_bytes(argv, "value", value, value_size);
+			if (!argv)
+				return -1;
+		}
+
+		return parse_elem(argv, info, key, NULL, key_size, value_size,
+				  flags, NULL);
+	} else if (is_prefix(*argv, "any") || is_prefix(*argv, "noexist") ||
+		   is_prefix(*argv, "exist")) {
+		if (!flags) {
+			err("flags specified multiple times: %s\n", *argv);
+			return -1;
+		}
+
+		if (is_prefix(*argv, "any"))
+			*flags = BPF_ANY;
+		else if (is_prefix(*argv, "noexist"))
+			*flags = BPF_NOEXIST;
+		else if (is_prefix(*argv, "exist"))
+			*flags = BPF_EXIST;
+
+		return parse_elem(argv + 1, info, key, value, key_size,
+				  value_size, NULL, value_fd);
+	}
+
+	err("expected key or value, got: %s\n", *argv);
+	return -1;
+}
+
+static int show_map_close(int fd, struct bpf_map_info *info)
+{
+	char *memlock;
+
+	memlock = get_fdinfo(fd, "memlock");
+	close(fd);
+
+	printf("%u: ", info->id);
+	if (info->type < ARRAY_SIZE(map_type_name))
+		printf("%s  ", map_type_name[info->type]);
+	else
+		printf("type %u  ", info->type);
+
+	if (*info->name)
+		printf("name %s  ", info->name);
+
+	printf("flags 0x%x\n", info->map_flags);
+	printf("\tkey %uB  value %uB  max_entries %u",
+	       info->key_size, info->value_size, info->max_entries);
+
+	if (memlock)
+		printf("  memlock %sB", memlock);
+	free(memlock);
+
+	printf("\n");
+
+	return 0;
+}
+
+static int do_show(int argc, char **argv)
+{
+	struct bpf_map_info info = {};
+	__u32 len = sizeof(info);
+	__u32 id = 0;
+	int err;
+	int fd;
+
+	if (argc == 2) {
+		fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
+		if (fd < 0)
+			return -1;
+
+		return show_map_close(fd, &info);
+	}
+
+	if (argc)
+		return BAD_ARG();
+
+	while (true) {
+		err = bpf_map_get_next_id(id, &id);
+		if (err) {
+			if (errno == ENOENT)
+				break;
+			err("can't get next map: %s\n", strerror(errno));
+			if (errno == EINVAL)
+				err("kernel too old?\n");
+			return -1;
+		}
+
+		fd = bpf_map_get_fd_by_id(id);
+		if (fd < 0) {
+			err("can't get map by id (%u): %s\n",
+			    id, strerror(errno));
+			return -1;
+		}
+
+		err = bpf_obj_get_info_by_fd(fd, &info, &len);
+		if (err) {
+			err("can't get map info: %s\n", strerror(errno));
+			close(fd);
+			return -1;
+		}
+
+		show_map_close(fd, &info);
+	}
+
+	return errno == ENOENT ? 0 : -1;
+}
+
+static int do_dump(int argc, char **argv)
+{
+	void *key, *value, *prev_key;
+	unsigned int num_elems = 0;
+	struct bpf_map_info info = {};
+	__u32 len = sizeof(info);
+	int err;
+	int fd;
+
+	if (argc != 2)
+		usage();
+
+	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
+	if (fd < 0)
+		return -1;
+
+	if (map_is_map_of_maps(info.type) || map_is_map_of_progs(info.type)) {
+		err("Dumping maps of maps and program maps not supported\n");
+		close(fd);
+		return -1;
+	}
+
+	key = malloc(info.key_size);
+	value = alloc_value(&info);
+	if (!key || !value) {
+		err("mem alloc failed\n");
+		err = -1;
+		goto exit_free;
+	}
+
+	prev_key = NULL;
+	while (true) {
+		err = bpf_map_get_next_key(fd, prev_key, key);
+		if (err) {
+			if (errno == ENOENT)
+				err = 0;
+			break;
+		}
+
+		if (!bpf_map_lookup_elem(fd, key, value)) {
+			print_entry(&info, key, value);
+		} else {
+			info("can't lookup element with key: ");
+			print_hex(key, info.key_size, " ");
+			printf("\n");
+		}
+
+		prev_key = key;
+		num_elems++;
+	}
+
+	printf("Found %u element%s\n", num_elems, num_elems != 1 ? "s" : "");
+
+exit_free:
+	free(key);
+	free(value);
+	close(fd);
+
+	return err;
+}
+
+static int do_update(int argc, char **argv)
+{
+	struct bpf_map_info info = {};
+	__u32 len = sizeof(info);
+	__u32 *value_fd = NULL;
+	__u32 flags = BPF_ANY;
+	void *key, *value;
+	int fd, err;
+
+	if (argc < 2)
+		usage();
+
+	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
+	if (fd < 0)
+		return -1;
+
+	key = malloc(info.key_size);
+	value = alloc_value(&info);
+	if (!key || !value) {
+		err("mem alloc failed");
+		err = -1;
+		goto exit_free;
+	}
+
+	err = parse_elem(argv, &info, key, value, info.key_size,
+			 info.value_size, &flags, &value_fd);
+	if (err)
+		goto exit_free;
+
+	err = bpf_map_update_elem(fd, key, value, flags);
+	if (err) {
+		err("update failed: %s\n", strerror(errno));
+		goto exit_free;
+	}
+
+exit_free:
+	if (value_fd)
+		close(*value_fd);
+	free(key);
+	free(value);
+	close(fd);
+
+	return err;
+}
+
+static int do_lookup(int argc, char **argv)
+{
+	struct bpf_map_info info = {};
+	__u32 len = sizeof(info);
+	void *key, *value;
+	int err;
+	int fd;
+
+	if (argc < 2)
+		usage();
+
+	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
+	if (fd < 0)
+		return -1;
+
+	key = malloc(info.key_size);
+	value = alloc_value(&info);
+	if (!key || !value) {
+		err("mem alloc failed");
+		err = -1;
+		goto exit_free;
+	}
+
+	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
+	if (err)
+		goto exit_free;
+
+	err = bpf_map_lookup_elem(fd, key, value);
+	if (!err) {
+		print_entry(&info, key, value);
+	} else if (errno == ENOENT) {
+		printf("key:\n");
+		print_hex(key, info.key_size, " ");
+		printf("\n\nNot found\n");
+	} else {
+		err("lookup failed: %s\n", strerror(errno));
+	}
+
+exit_free:
+	free(key);
+	free(value);
+	close(fd);
+
+	return err;
+}
+
+static int do_getnext(int argc, char **argv)
+{
+	struct bpf_map_info info = {};
+	__u32 len = sizeof(info);
+	void *key, *nextkey;
+	int err;
+	int fd;
+
+	if (argc < 2)
+		usage();
+
+	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
+	if (fd < 0)
+		return -1;
+
+	key = malloc(info.key_size);
+	nextkey = malloc(info.key_size);
+	if (!key || !nextkey) {
+		err("mem alloc failed");
+		err = -1;
+		goto exit_free;
+	}
+
+	if (argc) {
+		err = parse_elem(argv, &info, key, NULL, info.key_size, 0,
+				 NULL, NULL);
+		if (err)
+			goto exit_free;
+	} else {
+		free(key);
+		key = NULL;
+	}
+
+	err = bpf_map_get_next_key(fd, key, nextkey);
+	if (err) {
+		err("can't get next key: %s\n", strerror(errno));
+		goto exit_free;
+	}
+
+	if (key) {
+		printf("key:\n");
+		print_hex(key, info.key_size, " ");
+		printf("\n");
+	} else {
+		printf("key: None\n");
+	}
+
+	printf("next key:\n");
+	print_hex(nextkey, info.key_size, " ");
+	printf("\n");
+
+exit_free:
+	free(nextkey);
+	free(key);
+	close(fd);
+
+	return err;
+}
+
+static int do_delete(int argc, char **argv)
+{
+	struct bpf_map_info info = {};
+	__u32 len = sizeof(info);
+	void *key;
+	int err;
+	int fd;
+
+	if (argc < 2)
+		usage();
+
+	fd = map_parse_fd_and_info(&argc, &argv, &info, &len);
+	if (fd < 0)
+		return -1;
+
+	key = malloc(info.key_size);
+	if (!key) {
+		err("mem alloc failed");
+		err = -1;
+		goto exit_free;
+	}
+
+	err = parse_elem(argv, &info, key, NULL, info.key_size, 0, NULL, NULL);
+	if (err)
+		goto exit_free;
+
+	err = bpf_map_delete_elem(fd, key);
+	if (err)
+		err("delete failed: %s\n", strerror(errno));
+
+exit_free:
+	free(key);
+	close(fd);
+
+	return err;
+}
+
+static int do_pin(int argc, char **argv)
+{
+	return do_pin_any(argc, argv, bpf_map_get_fd_by_id);
+}
+
+static int do_help(int argc, char **argv)
+{
+	fprintf(stderr,
+		"Usage: %s %s show   [MAP]\n"
+		"       %s %s dump    MAP\n"
+		"       %s %s update  MAP  key BYTES value VALUE [UPDATE_FLAGS]\n"
+		"       %s %s lookup  MAP  key BYTES\n"
+		"       %s %s getnext MAP [key BYTES]\n"
+		"       %s %s delete  MAP  key BYTES\n"
+		"       %s %s pin     MAP  FILE\n"
+		"       %s %s help\n"
+		"\n"
+		"       MAP := { id MAP_ID | pinned FILE }\n"
+		"       " HELP_SPEC_PROGRAM "\n"
+		"       VALUE := { BYTES | MAP | PROG }\n"
+		"       UPDATE_FLAGS := { any | exist | noexist }\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],
+		bin_name, argv[-2], bin_name, argv[-2]);
+
+	return 0;
+}
+
+static const struct cmd cmds[] = {
+	{ "show",	do_show },
+	{ "help",	do_help },
+	{ "dump",	do_dump },
+	{ "update",	do_update },
+	{ "lookup",	do_lookup },
+	{ "getnext",	do_getnext },
+	{ "delete",	do_delete },
+	{ "pin",	do_pin },
+	{ 0 }
+};
+
+int do_map(int argc, char **argv)
+{
+	return cmd_select(cmds, argc, argv, do_help);
+}