1 files changed, 165 insertions, 51 deletions

diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
index 46bd716a9d86..cd5963cb6058 100644
--- a/tools/bpf/bpftool/main.c
+++ b/tools/bpf/bpftool/main.c
@@ -10,6 +10,8 @@
 #include <string.h>
 
 #include <bpf/bpf.h>
+#include <bpf/btf.h>
+#include <bpf/hashmap.h>
 #include <bpf/libbpf.h>
 
 #include "main.h"
@@ -28,9 +30,9 @@ bool show_pinned;
 bool block_mount;
 bool verifier_logs;
 bool relaxed_maps;
-struct pinned_obj_table prog_table;
-struct pinned_obj_table map_table;
-struct pinned_obj_table link_table;
+bool use_loader;
+struct btf *base_btf;
+struct hashmap *refs_table;
 
 static void __noreturn clean_and_exit(int i)
 {
@@ -60,22 +62,124 @@ static int do_help(int argc, char **argv)
 		"       %s version\n"
 		"\n"
 		"       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }\n"
-		"       " HELP_SPEC_OPTIONS "\n"
+		"       " HELP_SPEC_OPTIONS " |\n"
+		"                    {-V|--version} }\n"
 		"",
 		bin_name, bin_name, bin_name);
 
 	return 0;
 }
 
+static int do_batch(int argc, char **argv);
+static int do_version(int argc, char **argv);
+
+static const struct cmd commands[] = {
+	{ "help",	do_help },
+	{ "batch",	do_batch },
+	{ "prog",	do_prog },
+	{ "map",	do_map },
+	{ "link",	do_link },
+	{ "cgroup",	do_cgroup },
+	{ "perf",	do_perf },
+	{ "net",	do_net },
+	{ "feature",	do_feature },
+	{ "btf",	do_btf },
+	{ "gen",	do_gen },
+	{ "struct_ops",	do_struct_ops },
+	{ "iter",	do_iter },
+	{ "version",	do_version },
+	{ 0 }
+};
+
+#ifndef BPFTOOL_VERSION
+/* bpftool's major and minor version numbers are aligned on libbpf's. There is
+ * an offset of 6 for the version number, because bpftool's version was higher
+ * than libbpf's when we adopted this scheme. The patch number remains at 0
+ * for now. Set BPFTOOL_VERSION to override.
+ */
+#define BPFTOOL_MAJOR_VERSION (LIBBPF_MAJOR_VERSION + 6)
+#define BPFTOOL_MINOR_VERSION LIBBPF_MINOR_VERSION
+#define BPFTOOL_PATCH_VERSION 0
+#endif
+
+static void
+print_feature(const char *feature, bool state, unsigned int *nb_features)
+{
+	if (state) {
+		printf("%s %s", *nb_features ? "," : "", feature);
+		*nb_features = *nb_features + 1;
+	}
+}
+
 static int do_version(int argc, char **argv)
 {
+#ifdef HAVE_LIBBFD_SUPPORT
+	const bool has_libbfd = true;
+#else
+	const bool has_libbfd = false;
+#endif
+#ifdef HAVE_LLVM_SUPPORT
+	const bool has_llvm = true;
+#else
+	const bool has_llvm = false;
+#endif
+#ifdef BPFTOOL_WITHOUT_SKELETONS
+	const bool has_skeletons = false;
+#else
+	const bool has_skeletons = true;
+#endif
+	bool bootstrap = false;
+	int i;
+
+	for (i = 0; commands[i].cmd; i++) {
+		if (!strcmp(commands[i].cmd, "prog")) {
+			/* Assume we run a bootstrap version if "bpftool prog"
+			 * is not available.
+			 */
+			bootstrap = !commands[i].func;
+			break;
+		}
+	}
+
 	if (json_output) {
-		jsonw_start_object(json_wtr);
+		jsonw_start_object(json_wtr);	/* root object */
+
 		jsonw_name(json_wtr, "version");
+#ifdef BPFTOOL_VERSION
 		jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
-		jsonw_end_object(json_wtr);
+#else
+		jsonw_printf(json_wtr, "\"%d.%d.%d\"", BPFTOOL_MAJOR_VERSION,
+			     BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION);
+#endif
+		jsonw_name(json_wtr, "libbpf_version");
+		jsonw_printf(json_wtr, "\"%u.%u\"",
+			     libbpf_major_version(), libbpf_minor_version());
+
+		jsonw_name(json_wtr, "features");
+		jsonw_start_object(json_wtr);	/* features */
+		jsonw_bool_field(json_wtr, "libbfd", has_libbfd);
+		jsonw_bool_field(json_wtr, "llvm", has_llvm);
+		jsonw_bool_field(json_wtr, "skeletons", has_skeletons);
+		jsonw_bool_field(json_wtr, "bootstrap", bootstrap);
+		jsonw_end_object(json_wtr);	/* features */
+
+		jsonw_end_object(json_wtr);	/* root object */
 	} else {
+		unsigned int nb_features = 0;
+
+#ifdef BPFTOOL_VERSION
 		printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
+#else
+		printf("%s v%d.%d.%d\n", bin_name, BPFTOOL_MAJOR_VERSION,
+		       BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION);
+#endif
+		printf("using libbpf %s\n", libbpf_version_string());
+		printf("features:");
+		print_feature("libbfd", has_libbfd, &nb_features);
+		print_feature("llvm", has_llvm, &nb_features);
+		print_feature("skeletons", has_skeletons, &nb_features);
+		print_feature("bootstrap", bootstrap, &nb_features);
+		printf("\n");
 	}
 	return 0;
 }
@@ -92,9 +196,16 @@ int cmd_select(const struct cmd *cmds, int argc, char **argv,
 	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))
+	for (i = 0; cmds[i].cmd; i++) {
+		if (is_prefix(*argv, cmds[i].cmd)) {
+			if (!cmds[i].func) {
+				p_err("command '%s' is not supported in bootstrap mode",
+				      cmds[i].cmd);
+				return -1;
+			}
 			return cmds[i].func(argc - 1, argv + 1);
+		}
+	}
 
 	help(argc - 1, argv + 1);
 
@@ -209,26 +320,6 @@ static int make_args(char *line, char *n_argv[], int maxargs, int cmd_nb)
 	return n_argc;
 }
 
-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 },
-	{ "link",	do_link },
-	{ "cgroup",	do_cgroup },
-	{ "perf",	do_perf },
-	{ "net",	do_net },
-	{ "feature",	do_feature },
-	{ "btf",	do_btf },
-	{ "gen",	do_gen },
-	{ "struct_ops",	do_struct_ops },
-	{ "iter",	do_iter },
-	{ "version",	do_version },
-	{ 0 }
-};
-
 static int do_batch(int argc, char **argv)
 {
 	char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
@@ -237,18 +328,18 @@ static int do_batch(int argc, char **argv)
 	int n_argc;
 	FILE *fp;
 	char *cp;
-	int err;
+	int err = 0;
 	int i;
 
 	if (argc < 2) {
 		p_err("too few parameters for batch");
 		return -1;
-	} else if (!is_prefix(*argv, "file")) {
-		p_err("expected 'file', got: %s", *argv);
-		return -1;
 	} else if (argc > 2) {
 		p_err("too many parameters for batch");
 		return -1;
+	} else if (!is_prefix(*argv, "file")) {
+		p_err("expected 'file', got: %s", *argv);
+		return -1;
 	}
 	NEXT_ARG();
 
@@ -279,7 +370,7 @@ static int do_batch(int argc, char **argv)
 		while ((cp = strstr(buf, "\\\n")) != NULL) {
 			if (!fgets(contline, sizeof(contline), fp) ||
 			    strlen(contline) == 0) {
-				p_err("missing continuation line on command %d",
+				p_err("missing continuation line on command %u",
 				      lines);
 				err = -1;
 				goto err_close;
@@ -290,7 +381,7 @@ static int do_batch(int argc, char **argv)
 				*cp = '\0';
 
 			if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
-				p_err("command %d is too long", lines);
+				p_err("command %u is too long", lines);
 				err = -1;
 				goto err_close;
 			}
@@ -301,8 +392,10 @@ static int do_batch(int argc, char **argv)
 		n_argc = make_args(buf, n_argv, BATCH_ARG_NB_MAX, lines);
 		if (!n_argc)
 			continue;
-		if (n_argc < 0)
+		if (n_argc < 0) {
+			err = n_argc;
 			goto err_close;
+		}
 
 		if (json_output) {
 			jsonw_start_object(json_wtr);
@@ -314,7 +407,7 @@ static int do_batch(int argc, char **argv)
 			jsonw_name(json_wtr, "output");
 		}
 
-		err = cmd_select(cmds, n_argc, n_argv, do_help);
+		err = cmd_select(commands, n_argc, n_argv, do_help);
 
 		if (json_output)
 			jsonw_end_object(json_wtr);
@@ -330,8 +423,7 @@ static int do_batch(int argc, char **argv)
 		err = -1;
 	} else {
 		if (!json_output)
-			printf("processed %d commands\n", lines);
-		err = 0;
+			printf("processed %u commands\n", lines);
 	}
 err_close:
 	if (fp != stdin)
@@ -354,27 +446,39 @@ int main(int argc, char **argv)
 		{ "mapcompat",	no_argument,	NULL,	'm' },
 		{ "nomount",	no_argument,	NULL,	'n' },
 		{ "debug",	no_argument,	NULL,	'd' },
+		{ "use-loader",	no_argument,	NULL,	'L' },
+		{ "base-btf",	required_argument, NULL, 'B' },
 		{ 0 }
 	};
+	bool version_requested = false;
 	int opt, ret;
 
+	setlinebuf(stdout);
+
+#ifdef USE_LIBCAP
+	/* Libcap < 2.63 hooks before main() to compute the number of
+	 * capabilities of the running kernel, and doing so it calls prctl()
+	 * which may fail and set errno to non-zero.
+	 * Let's reset errno to make sure this does not interfere with the
+	 * batch mode.
+	 */
+	errno = 0;
+#endif
+
 	last_do_help = do_help;
 	pretty_output = false;
 	json_output = false;
 	show_pinned = false;
 	block_mount = false;
-	bin_name = argv[0];
-
-	hash_init(prog_table.table);
-	hash_init(map_table.table);
-	hash_init(link_table.table);
+	bin_name = "bpftool";
 
 	opterr = 0;
-	while ((opt = getopt_long(argc, argv, "Vhpjfmnd",
+	while ((opt = getopt_long(argc, argv, "VhpjfLmndB:l",
 				  options, NULL)) >= 0) {
 		switch (opt) {
 		case 'V':
-			return do_version(argc, argv);
+			version_requested = true;
+			break;
 		case 'h':
 			return do_help(argc, argv);
 		case 'p':
@@ -404,6 +508,17 @@ int main(int argc, char **argv)
 			libbpf_set_print(print_all_levels);
 			verifier_logs = true;
 			break;
+		case 'B':
+			base_btf = btf__parse(optarg, NULL);
+			if (!base_btf) {
+				p_err("failed to parse base BTF at '%s': %d\n",
+				      optarg, -errno);
+				return -1;
+			}
+			break;
+		case 'L':
+			use_loader = true;
+			break;
 		default:
 			p_err("unrecognized option '%s'", argv[optind - 1]);
 			if (json_output)
@@ -418,16 +533,15 @@ int main(int argc, char **argv)
 	if (argc < 0)
 		usage();
 
-	ret = cmd_select(cmds, argc, argv, do_help);
+	if (version_requested)
+		return do_version(argc, argv);
+
+	ret = cmd_select(commands, argc, argv, do_help);
 
 	if (json_output)
 		jsonw_destroy(&json_wtr);
 
-	if (show_pinned) {
-		delete_pinned_obj_table(&prog_table);
-		delete_pinned_obj_table(&map_table);
-		delete_pinned_obj_table(&link_table);
-	}
+	btf__free(base_btf);
 
 	return ret;
 }