xref: /linux/tools/bpf/bpftool/netlink_dumper.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 // Copyright (C) 2018 Facebook
3 
4 #include <stdlib.h>
5 #include <string.h>
6 #include <bpf/libbpf.h>
7 #include <linux/rtnetlink.h>
8 #include <linux/tc_act/tc_bpf.h>
9 
10 #include "bpf/nlattr.h"
11 #include "main.h"
12 #include "netlink_dumper.h"
13 
14 static void xdp_dump_prog_id(struct nlattr **tb, int attr,
15 			     const char *mode,
16 			     bool new_json_object)
17 {
18 	if (!tb[attr])
19 		return;
20 
21 	if (new_json_object)
22 		NET_START_OBJECT
23 	NET_DUMP_STR("mode", " %s", mode);
24 	NET_DUMP_UINT("id", " id %u", libbpf_nla_getattr_u32(tb[attr]))
25 	if (new_json_object)
26 		NET_END_OBJECT
27 }
28 
29 static int do_xdp_dump_one(struct nlattr *attr, unsigned int ifindex,
30 			   const char *name)
31 {
32 	struct nlattr *tb[IFLA_XDP_MAX + 1];
33 	unsigned char mode;
34 
35 	if (libbpf_nla_parse_nested(tb, IFLA_XDP_MAX, attr, NULL) < 0)
36 		return -1;
37 
38 	if (!tb[IFLA_XDP_ATTACHED])
39 		return 0;
40 
41 	mode = libbpf_nla_getattr_u8(tb[IFLA_XDP_ATTACHED]);
42 	if (mode == XDP_ATTACHED_NONE)
43 		return 0;
44 
45 	NET_START_OBJECT;
46 	if (name)
47 		NET_DUMP_STR("devname", "%s", name);
48 	NET_DUMP_UINT("ifindex", "(%d)", ifindex);
49 
50 	if (mode == XDP_ATTACHED_MULTI) {
51 		if (json_output) {
52 			jsonw_name(json_wtr, "multi_attachments");
53 			jsonw_start_array(json_wtr);
54 		}
55 		xdp_dump_prog_id(tb, IFLA_XDP_SKB_PROG_ID, "generic", true);
56 		xdp_dump_prog_id(tb, IFLA_XDP_DRV_PROG_ID, "driver", true);
57 		xdp_dump_prog_id(tb, IFLA_XDP_HW_PROG_ID, "offload", true);
58 		if (json_output)
59 			jsonw_end_array(json_wtr);
60 	} else if (mode == XDP_ATTACHED_DRV) {
61 		xdp_dump_prog_id(tb, IFLA_XDP_PROG_ID, "driver", false);
62 	} else if (mode == XDP_ATTACHED_SKB) {
63 		xdp_dump_prog_id(tb, IFLA_XDP_PROG_ID, "generic", false);
64 	} else if (mode == XDP_ATTACHED_HW) {
65 		xdp_dump_prog_id(tb, IFLA_XDP_PROG_ID, "offload", false);
66 	}
67 
68 	NET_END_OBJECT_FINAL;
69 	return 0;
70 }
71 
72 int do_xdp_dump(struct ifinfomsg *ifinfo, struct nlattr **tb)
73 {
74 	if (!tb[IFLA_XDP])
75 		return 0;
76 
77 	return do_xdp_dump_one(tb[IFLA_XDP], ifinfo->ifi_index,
78 			       libbpf_nla_getattr_str(tb[IFLA_IFNAME]));
79 }
80 
81 static int do_bpf_dump_one_act(struct nlattr *attr)
82 {
83 	struct nlattr *tb[TCA_ACT_BPF_MAX + 1];
84 
85 	if (libbpf_nla_parse_nested(tb, TCA_ACT_BPF_MAX, attr, NULL) < 0)
86 		return -LIBBPF_ERRNO__NLPARSE;
87 
88 	if (!tb[TCA_ACT_BPF_PARMS])
89 		return -LIBBPF_ERRNO__NLPARSE;
90 
91 	NET_START_OBJECT_NESTED2;
92 	if (tb[TCA_ACT_BPF_NAME])
93 		NET_DUMP_STR("name", "%s",
94 			     libbpf_nla_getattr_str(tb[TCA_ACT_BPF_NAME]));
95 	if (tb[TCA_ACT_BPF_ID])
96 		NET_DUMP_UINT("id", " id %u",
97 			      libbpf_nla_getattr_u32(tb[TCA_ACT_BPF_ID]));
98 	NET_END_OBJECT_NESTED;
99 	return 0;
100 }
101 
102 static int do_dump_one_act(struct nlattr *attr)
103 {
104 	struct nlattr *tb[TCA_ACT_MAX + 1];
105 
106 	if (!attr)
107 		return 0;
108 
109 	if (libbpf_nla_parse_nested(tb, TCA_ACT_MAX, attr, NULL) < 0)
110 		return -LIBBPF_ERRNO__NLPARSE;
111 
112 	if (tb[TCA_ACT_KIND] &&
113 	    strcmp(libbpf_nla_data(tb[TCA_ACT_KIND]), "bpf") == 0)
114 		return do_bpf_dump_one_act(tb[TCA_ACT_OPTIONS]);
115 
116 	return 0;
117 }
118 
119 static int do_bpf_act_dump(struct nlattr *attr)
120 {
121 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
122 	int act, ret;
123 
124 	if (libbpf_nla_parse_nested(tb, TCA_ACT_MAX_PRIO, attr, NULL) < 0)
125 		return -LIBBPF_ERRNO__NLPARSE;
126 
127 	NET_START_ARRAY("act", " %s [");
128 	for (act = 0; act <= TCA_ACT_MAX_PRIO; act++) {
129 		ret = do_dump_one_act(tb[act]);
130 		if (ret)
131 			break;
132 	}
133 	NET_END_ARRAY("] ");
134 
135 	return ret;
136 }
137 
138 static int do_bpf_filter_dump(struct nlattr *attr)
139 {
140 	struct nlattr *tb[TCA_BPF_MAX + 1];
141 	int ret;
142 
143 	if (libbpf_nla_parse_nested(tb, TCA_BPF_MAX, attr, NULL) < 0)
144 		return -LIBBPF_ERRNO__NLPARSE;
145 
146 	if (tb[TCA_BPF_NAME])
147 		NET_DUMP_STR("name", " %s",
148 			     libbpf_nla_getattr_str(tb[TCA_BPF_NAME]));
149 	if (tb[TCA_BPF_ID])
150 		NET_DUMP_UINT("id", " id %u",
151 			      libbpf_nla_getattr_u32(tb[TCA_BPF_ID]));
152 	if (tb[TCA_BPF_ACT]) {
153 		ret = do_bpf_act_dump(tb[TCA_BPF_ACT]);
154 		if (ret)
155 			return ret;
156 	}
157 
158 	return 0;
159 }
160 
161 int do_filter_dump(struct tcmsg *info, struct nlattr **tb, const char *kind,
162 		   const char *devname, int ifindex)
163 {
164 	int ret = 0;
165 
166 	if (tb[TCA_OPTIONS] &&
167 	    strcmp(libbpf_nla_data(tb[TCA_KIND]), "bpf") == 0) {
168 		NET_START_OBJECT;
169 		if (devname[0] != '\0')
170 			NET_DUMP_STR("devname", "%s", devname);
171 		NET_DUMP_UINT("ifindex", "(%u)", ifindex);
172 		NET_DUMP_STR("kind", " %s", kind);
173 		ret = do_bpf_filter_dump(tb[TCA_OPTIONS]);
174 		NET_END_OBJECT_FINAL;
175 	}
176 
177 	return ret;
178 }
179