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, 212 insertions, 0 deletions

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
new file mode 100644
index 000000000000..e02d00d6e00b
--- /dev/null
+++ b/tools/bpf/bpftool/main.c
@@ -0,0 +1,212 @@
+/*
+ * 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 <bfd.h>
+#include <ctype.h>
+#include <errno.h>
+#include <linux/bpf.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <bpf.h>
+
+#include "main.h"
+
+const char *bin_name;
+static int last_argc;
+static char **last_argv;
+static int (*last_do_help)(int argc, char **argv);
+
+void usage(void)
+{
+	last_do_help(last_argc - 1, last_argv + 1);
+
+	exit(-1);
+}
+
+static int do_help(int argc, char **argv)
+{
+	fprintf(stderr,
+		"Usage: %s OBJECT { COMMAND | help }\n"
+		"       %s batch file FILE\n"
+		"\n"
+		"       OBJECT := { prog | map }\n",
+		bin_name, bin_name);
+
+	return 0;
+}
+
+int cmd_select(const struct cmd *cmds, int argc, char **argv,
+	       int (*help)(int argc, char **argv))
+{
+	unsigned int i;
+
+	last_argc = argc;
+	last_argv = argv;
+	last_do_help = help;
+
+	if (argc < 1 && cmds[0].func)
+		return cmds[0].func(argc, argv);
+
+	for (i = 0; cmds[i].func; i++)
+		if (is_prefix(*argv, cmds[i].cmd))
+			return cmds[i].func(argc - 1, argv + 1);
+
+	help(argc - 1, argv + 1);
+
+	return -1;
+}
+
+bool is_prefix(const char *pfx, const char *str)
+{
+	if (!pfx)
+		return false;
+	if (strlen(str) < strlen(pfx))
+		return false;
+
+	return !memcmp(str, pfx, strlen(pfx));
+}
+
+void print_hex(void *arg, unsigned int n, const char *sep)
+{
+	unsigned char *data = arg;
+	unsigned int i;
+
+	for (i = 0; i < n; i++) {
+		const char *pfx = "";
+
+		if (!i)
+			/* nothing */;
+		else if (!(i % 16))
+			printf("\n");
+		else if (!(i % 8))
+			printf("  ");
+		else
+			pfx = sep;
+
+		printf("%s%02hhx", i ? pfx : "", data[i]);
+	}
+}
+
+static int do_batch(int argc, char **argv);
+
+static const struct cmd cmds[] = {
+	{ "help",	do_help },
+	{ "batch",	do_batch },
+	{ "prog",	do_prog },
+	{ "map",	do_map },
+	{ 0 }
+};
+
+static int do_batch(int argc, char **argv)
+{
+	unsigned int lines = 0;
+	char *n_argv[4096];
+	char buf[65536];
+	int n_argc;
+	FILE *fp;
+	int err;
+
+	if (argc < 2) {
+		err("too few parameters for batch\n");
+		return -1;
+	} else if (!is_prefix(*argv, "file")) {
+		err("expected 'file', got: %s\n", *argv);
+		return -1;
+	} else if (argc > 2) {
+		err("too many parameters for batch\n");
+		return -1;
+	}
+	NEXT_ARG();
+
+	fp = fopen(*argv, "r");
+	if (!fp) {
+		err("Can't open file (%s): %s\n", *argv, strerror(errno));
+		return -1;
+	}
+
+	while (fgets(buf, sizeof(buf), fp)) {
+		if (strlen(buf) == sizeof(buf) - 1) {
+			errno = E2BIG;
+			break;
+		}
+
+		n_argc = 0;
+		n_argv[n_argc] = strtok(buf, " \t\n");
+
+		while (n_argv[n_argc]) {
+			n_argc++;
+			if (n_argc == ARRAY_SIZE(n_argv)) {
+				err("line %d has too many arguments, skip\n",
+				    lines);
+				n_argc = 0;
+				break;
+			}
+			n_argv[n_argc] = strtok(NULL, " \t\n");
+		}
+
+		if (!n_argc)
+			continue;
+
+		err = cmd_select(cmds, n_argc, n_argv, do_help);
+		if (err)
+			goto err_close;
+
+		lines++;
+	}
+
+	if (errno && errno != ENOENT) {
+		perror("reading batch file failed");
+		err = -1;
+	} else {
+		info("processed %d lines\n", lines);
+		err = 0;
+	}
+err_close:
+	fclose(fp);
+
+	return err;
+}
+
+int main(int argc, char **argv)
+{
+	bin_name = argv[0];
+	NEXT_ARG();
+
+	bfd_init();
+
+	return cmd_select(cmds, argc, argv, do_help);
+}