Merge branch 'bpftool_sockmap'

John Fastabend says:

====================
The first patch adds support for attaching programs to maps. This is
needed to support sock{map|hash} use from bpftool. Currently, I carry
around custom code to do this so doing it using standard bpftool will
be great.

The second patch adds a compat mode to ignore non-zero entries in
the map def. This allows using bpftool with maps that have a extra
fields that the user knows can be ignored. This is needed to work
correctly with maps being loaded by other tools or directly via
syscalls.

v3: add bash completion and doc updates for --mapcompat
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

tools/bpf/bpftool/Documentation/bpftool-prog.rst

@@ -25,6 +25,8 @@ MAP COMMANDS
 |	**bpftool** **prog dump jited**  *PROG* [{**file** *FILE* | **opcodes**}]
 |	**bpftool** **prog pin** *PROG* *FILE*
 |	**bpftool** **prog load** *OBJ* *FILE* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*]
+|       **bpftool** **prog attach** *PROG* *ATTACH_TYPE* *MAP*
+|       **bpftool** **prog detach** *PROG* *ATTACH_TYPE* *MAP*
 |	**bpftool** **prog help**
 |
 |	*MAP* := { **id** *MAP_ID* | **pinned** *FILE* }
@@ -37,6 +39,7 @@ MAP COMMANDS
 |		**cgroup/bind4** | **cgroup/bind6** | **cgroup/post_bind4** | **cgroup/post_bind6** |
 |		**cgroup/connect4** | **cgroup/connect6** | **cgroup/sendmsg4** | **cgroup/sendmsg6**
 |	}
+|       *ATTACH_TYPE* := { **msg_verdict** | **skb_verdict** | **skb_parse** }
 
 
 DESCRIPTION
@@ -90,6 +93,14 @@ DESCRIPTION
 
 		  Note: *FILE* must be located in *bpffs* mount.
 
+        **bpftool prog attach** *PROG* *ATTACH_TYPE* *MAP*
+                  Attach bpf program *PROG* (with type specified by *ATTACH_TYPE*)
+                  to the map *MAP*.
+
+        **bpftool prog detach** *PROG* *ATTACH_TYPE* *MAP*
+                  Detach bpf program *PROG* (with type specified by *ATTACH_TYPE*)
+                  from the map *MAP*.
+
 	**bpftool prog help**
 		  Print short help message.
 

tools/bpf/bpftool/Documentation/bpftool.rst

@@ -26,7 +26,7 @@ SYNOPSIS
 	| **pin** | **event_pipe** | **help** }
 
 	*PROG-COMMANDS* := { **show** | **list** | **dump jited** | **dump xlated** | **pin**
-	| **load** | **help** }
+	| **load** | **attach** | **detach** | **help** }
 
 	*CGROUP-COMMANDS* := { **show** | **list** | **attach** | **detach** | **help** }
 
@@ -57,6 +57,10 @@ OPTIONS
 	-p, --pretty
 		  Generate human-readable JSON output. Implies **-j**.
 
+	-m, --mapcompat
+		  Allow loading maps with unknown map definitions.
+
+
 SEE ALSO
 ========
 	**bpftool-map**\ (8), **bpftool-prog**\ (8), **bpftool-cgroup**\ (8)

tools/bpf/bpftool/bash-completion/bpftool

@@ -184,7 +184,7 @@ _bpftool()
 
     # Deal with options
     if [[ ${words[cword]} == -* ]]; then
-        local c='--version --json --pretty --bpffs'
+        local c='--version --json --pretty --bpffs --mapcompat'
         COMPREPLY=( $( compgen -W "$c" -- "$cur" ) )
         return 0
     fi
@@ -292,6 +292,23 @@ _bpftool()
                     fi
                     return 0
                     ;;
+                attach|detach)
+                    if [[ ${#words[@]} == 7 ]]; then
+                        COMPREPLY=( $( compgen -W "id pinned" -- "$cur" ) )
+                        return 0
+                    fi
+
+                    if [[ ${#words[@]} == 6 ]]; then
+                        COMPREPLY=( $( compgen -W "msg_verdict skb_verdict skb_parse" -- "$cur" ) )
+                        return 0
+                    fi
+
+                    if [[ $prev == "$command" ]]; then
+                        COMPREPLY=( $( compgen -W "id pinned" -- "$cur" ) )
+                        return 0
+                    fi
+                    return 0
+                    ;;
                 load)
                     local obj
 
@@ -347,7 +364,7 @@ _bpftool()
                     ;;
                 *)
                     [[ $prev == $object ]] && \
-                        COMPREPLY=( $( compgen -W 'dump help pin load \
+                        COMPREPLY=( $( compgen -W 'dump help pin attach detach load \
                             show list' -- "$cur" ) )
                     ;;
             esac

tools/bpf/bpftool/main.c

@@ -55,6 +55,7 @@ json_writer_t *json_wtr;
 bool pretty_output;
 bool json_output;
 bool show_pinned;
+int bpf_flags;
 struct pinned_obj_table prog_table;
 struct pinned_obj_table map_table;
 
@@ -341,6 +342,7 @@ int main(int argc, char **argv)
 		{ "pretty",	no_argument,	NULL,	'p' },
 		{ "version",	no_argument,	NULL,	'V' },
 		{ "bpffs",	no_argument,	NULL,	'f' },
+		{ "mapcompat",	no_argument,	NULL,	'm' },
 		{ 0 }
 	};
 	int opt, ret;
@@ -355,7 +357,7 @@ int main(int argc, char **argv)
 	hash_init(map_table.table);
 
 	opterr = 0;
-	while ((opt = getopt_long(argc, argv, "Vhpjf",
+	while ((opt = getopt_long(argc, argv, "Vhpjfm",
 				  options, NULL)) >= 0) {
 		switch (opt) {
 		case 'V':
@@ -379,6 +381,9 @@ int main(int argc, char **argv)
 		case 'f':
 			show_pinned = true;
 			break;
+		case 'm':
+			bpf_flags = MAPS_RELAX_COMPAT;
+			break;
 		default:
 			p_err("unrecognized option '%s'", argv[optind - 1]);
 			if (json_output)

tools/bpf/bpftool/main.h

@@ -74,7 +74,7 @@
 #define HELP_SPEC_PROGRAM						\
 	"PROG := { id PROG_ID | pinned FILE | tag PROG_TAG }"
 #define HELP_SPEC_OPTIONS						\
-	"OPTIONS := { {-j|--json} [{-p|--pretty}] | {-f|--bpffs} }"
+	"OPTIONS := { {-j|--json} [{-p|--pretty}] | {-f|--bpffs} | {-m|--mapcompat}"
 #define HELP_SPEC_MAP							\
 	"MAP := { id MAP_ID | pinned FILE }"
 
@@ -89,6 +89,7 @@ extern const char *bin_name;
 extern json_writer_t *json_wtr;
 extern bool json_output;
 extern bool show_pinned;
+extern int bpf_flags;
 extern struct pinned_obj_table prog_table;
 extern struct pinned_obj_table map_table;
 

tools/bpf/bpftool/prog.c

@@ -77,6 +77,26 @@ static const char * const prog_type_name[] = {
 	[BPF_PROG_TYPE_FLOW_DISSECTOR]	= "flow_dissector",
 };
 
+static const char * const attach_type_strings[] = {
+	[BPF_SK_SKB_STREAM_PARSER] = "stream_parser",
+	[BPF_SK_SKB_STREAM_VERDICT] = "stream_verdict",
+	[BPF_SK_MSG_VERDICT] = "msg_verdict",
+	[__MAX_BPF_ATTACH_TYPE] = NULL,
+};
+
+enum bpf_attach_type parse_attach_type(const char *str)
+{
+	enum bpf_attach_type type;
+
+	for (type = 0; type < __MAX_BPF_ATTACH_TYPE; type++) {
+		if (attach_type_strings[type] &&
+		    is_prefix(str, attach_type_strings[type]))
+			return type;
+	}
+
+	return __MAX_BPF_ATTACH_TYPE;
+}
+
 static void print_boot_time(__u64 nsecs, char *buf, unsigned int size)
 {
 	struct timespec real_time_ts, boot_time_ts;
@@ -697,6 +717,77 @@ int map_replace_compar(const void *p1, const void *p2)
 	return a->idx - b->idx;
 }
 
+static int do_attach(int argc, char **argv)
+{
+	enum bpf_attach_type attach_type;
+	int err, mapfd, progfd;
+
+	if (!REQ_ARGS(5)) {
+		p_err("too few parameters for map attach");
+		return -EINVAL;
+	}
+
+	progfd = prog_parse_fd(&argc, &argv);
+	if (progfd < 0)
+		return progfd;
+
+	attach_type = parse_attach_type(*argv);
+	if (attach_type == __MAX_BPF_ATTACH_TYPE) {
+		p_err("invalid attach type");
+		return -EINVAL;
+	}
+	NEXT_ARG();
+
+	mapfd = map_parse_fd(&argc, &argv);
+	if (mapfd < 0)
+		return mapfd;
+
+	err = bpf_prog_attach(progfd, mapfd, attach_type, 0);
+	if (err) {
+		p_err("failed prog attach to map");
+		return -EINVAL;
+	}
+
+	if (json_output)
+		jsonw_null(json_wtr);
+	return 0;
+}
+
+static int do_detach(int argc, char **argv)
+{
+	enum bpf_attach_type attach_type;
+	int err, mapfd, progfd;
+
+	if (!REQ_ARGS(5)) {
+		p_err("too few parameters for map detach");
+		return -EINVAL;
+	}
+
+	progfd = prog_parse_fd(&argc, &argv);
+	if (progfd < 0)
+		return progfd;
+
+	attach_type = parse_attach_type(*argv);
+	if (attach_type == __MAX_BPF_ATTACH_TYPE) {
+		p_err("invalid attach type");
+		return -EINVAL;
+	}
+	NEXT_ARG();
+
+	mapfd = map_parse_fd(&argc, &argv);
+	if (mapfd < 0)
+		return mapfd;
+
+	err = bpf_prog_detach2(progfd, mapfd, attach_type);
+	if (err) {
+		p_err("failed prog detach from map");
+		return -EINVAL;
+	}
+
+	if (json_output)
+		jsonw_null(json_wtr);
+	return 0;
+}
 static int do_load(int argc, char **argv)
 {
 	enum bpf_attach_type expected_attach_type;
@@ -817,7 +908,7 @@ static int do_load(int argc, char **argv)
 		}
 	}
 
-	obj = bpf_object__open_xattr(&attr);
+	obj = __bpf_object__open_xattr(&attr, bpf_flags);
 	if (IS_ERR_OR_NULL(obj)) {
 		p_err("failed to open object file");
 		goto err_free_reuse_maps;
@@ -942,6 +1033,8 @@ static int do_help(int argc, char **argv)
 		"       %s %s pin   PROG FILE\n"
 		"       %s %s load  OBJ  FILE [type TYPE] [dev NAME] \\\n"
 		"                         [map { idx IDX | name NAME } MAP]\n"
+		"       %s %s attach PROG ATTACH_TYPE MAP\n"
+		"       %s %s detach PROG ATTACH_TYPE MAP\n"
 		"       %s %s help\n"
 		"\n"
 		"       " HELP_SPEC_MAP "\n"
@@ -953,10 +1046,12 @@ static int do_help(int argc, char **argv)
 		"                 cgroup/bind4 | cgroup/bind6 | cgroup/post_bind4 |\n"
 		"                 cgroup/post_bind6 | cgroup/connect4 | cgroup/connect6 |\n"
 		"                 cgroup/sendmsg4 | cgroup/sendmsg6 }\n"
+		"       ATTACH_TYPE := { msg_verdict | skb_verdict | skb_parse }\n"
 		"       " HELP_SPEC_OPTIONS "\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], bin_name, argv[-2],
+		bin_name, argv[-2], bin_name, argv[-2]);
 
 	return 0;
 }
@@ -968,6 +1063,8 @@ static const struct cmd cmds[] = {
 	{ "dump",	do_dump },
 	{ "pin",	do_pin },
 	{ "load",	do_load },
+	{ "attach",	do_attach },
+	{ "detach",	do_detach },
 	{ 0 }
 };
 

tools/lib/bpf/bpf.h

@@ -69,6 +69,9 @@ struct bpf_load_program_attr {
 	__u32 prog_ifindex;
 };
 
+/* Flags to direct loading requirements */
+#define MAPS_RELAX_COMPAT	0x01
+
 /* Recommend log buffer size */
 #define BPF_LOG_BUF_SIZE (256 * 1024)
 int bpf_load_program_xattr(const struct bpf_load_program_attr *load_attr,

tools/lib/bpf/libbpf.c

@@ -562,8 +562,9 @@ static int compare_bpf_map(const void *_a, const void *_b)
 }
 
 static int
-bpf_object__init_maps(struct bpf_object *obj)
+bpf_object__init_maps(struct bpf_object *obj, int flags)
 {
+	bool strict = !(flags & MAPS_RELAX_COMPAT);
 	int i, map_idx, map_def_sz, nr_maps = 0;
 	Elf_Scn *scn;
 	Elf_Data *data;
@@ -685,7 +686,8 @@ bpf_object__init_maps(struct bpf_object *obj)
 						   "has unrecognized, non-zero "
 						   "options\n",
 						   obj->path, map_name);
-					return -EINVAL;
+					if (strict)
+						return -EINVAL;
 				}
 			}
 			memcpy(&obj->maps[map_idx].def, def,
@@ -716,7 +718,7 @@ static bool section_have_execinstr(struct bpf_object *obj, int idx)
 	return false;
 }
 
-static int bpf_object__elf_collect(struct bpf_object *obj)
+static int bpf_object__elf_collect(struct bpf_object *obj, int flags)
 {
 	Elf *elf = obj->efile.elf;
 	GElf_Ehdr *ep = &obj->efile.ehdr;
@@ -843,7 +845,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj)
 		return LIBBPF_ERRNO__FORMAT;
 	}
 	if (obj->efile.maps_shndx >= 0) {
-		err = bpf_object__init_maps(obj);
+		err = bpf_object__init_maps(obj, flags);
 		if (err)
 			goto out;
 	}
@@ -1515,7 +1517,7 @@ static int bpf_object__validate(struct bpf_object *obj, bool needs_kver)
 
 static struct bpf_object *
 __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz,
-		   bool needs_kver)
+		   bool needs_kver, int flags)
 {
 	struct bpf_object *obj;
 	int err;
@@ -1531,7 +1533,7 @@ __bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz,
 
 	CHECK_ERR(bpf_object__elf_init(obj), err, out);
 	CHECK_ERR(bpf_object__check_endianness(obj), err, out);
-	CHECK_ERR(bpf_object__elf_collect(obj), err, out);
+	CHECK_ERR(bpf_object__elf_collect(obj, flags), err, out);
 	CHECK_ERR(bpf_object__collect_reloc(obj), err, out);
 	CHECK_ERR(bpf_object__validate(obj, needs_kver), err, out);
 
@@ -1542,7 +1544,8 @@ out:
 	return ERR_PTR(err);
 }
 
-struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr)
+struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr,
+					    int flags)
 {
 	/* param validation */
 	if (!attr->file)
@@ -1551,7 +1554,13 @@ struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr)
 	pr_debug("loading %s\n", attr->file);
 
 	return __bpf_object__open(attr->file, NULL, 0,
-				  bpf_prog_type__needs_kver(attr->prog_type));
+				  bpf_prog_type__needs_kver(attr->prog_type),
+				  flags);
+}
+
+struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr)
+{
+	return __bpf_object__open_xattr(attr, 0);
 }
 
 struct bpf_object *bpf_object__open(const char *path)
@@ -1584,7 +1593,7 @@ struct bpf_object *bpf_object__open_buffer(void *obj_buf,
 	pr_debug("loading object '%s' from buffer\n",
 		 name);
 
-	return __bpf_object__open(name, obj_buf, obj_buf_sz, true);
+	return __bpf_object__open(name, obj_buf, obj_buf_sz, true, true);
 }
 
 int bpf_object__unload(struct bpf_object *obj)

tools/lib/bpf/libbpf.h

@@ -61,6 +61,8 @@ struct bpf_object_open_attr {
 
 struct bpf_object *bpf_object__open(const char *path);
 struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr);
+struct bpf_object *__bpf_object__open_xattr(struct bpf_object_open_attr *attr,
+					    int flags);
 struct bpf_object *bpf_object__open_buffer(void *obj_buf,
 					   size_t obj_buf_sz,
 					   const char *name);