1#include <net/if.h>
2#include <errno.h>
3#include <string.h>
4#include <ctype.h>
5#include <stdbool.h>
6
7#include <netlink/genl/genl.h>
8#include <netlink/genl/family.h>
9#include <netlink/genl/ctrl.h>
10#include <netlink/msg.h>
11#include <netlink/attr.h>
12
13#include "nl80211.h"
14#include "iw.h"
15
16struct link_result {
17	uint8_t bssid[8];
18	bool link_found;
19	bool anything_found;
20};
21
22static struct link_result lr = { .link_found = false };
23
24static int link_bss_handler(struct nl_msg *msg, void *arg)
25{
26	struct nlattr *tb[NL80211_ATTR_MAX + 1];
27	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
28	struct nlattr *bss[NL80211_BSS_MAX + 1];
29	static struct nla_policy bss_policy[NL80211_BSS_MAX + 1] = {
30		[NL80211_BSS_TSF] = { .type = NLA_U64 },
31		[NL80211_BSS_FREQUENCY] = { .type = NLA_U32 },
32		[NL80211_BSS_BSSID] = { },
33		[NL80211_BSS_BEACON_INTERVAL] = { .type = NLA_U16 },
34		[NL80211_BSS_CAPABILITY] = { .type = NLA_U16 },
35		[NL80211_BSS_INFORMATION_ELEMENTS] = { },
36		[NL80211_BSS_SIGNAL_MBM] = { .type = NLA_U32 },
37		[NL80211_BSS_SIGNAL_UNSPEC] = { .type = NLA_U8 },
38		[NL80211_BSS_STATUS] = { .type = NLA_U32 },
39	};
40	struct link_result *result = arg;
41	char mac_addr[20], dev[20];
42
43	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
44		  genlmsg_attrlen(gnlh, 0), NULL);
45
46	if (!tb[NL80211_ATTR_BSS]) {
47		fprintf(stderr, "bss info missing!\n");
48		return NL_SKIP;
49	}
50	if (nla_parse_nested(bss, NL80211_BSS_MAX,
51			     tb[NL80211_ATTR_BSS],
52			     bss_policy)) {
53		fprintf(stderr, "failed to parse nested attributes!\n");
54		return NL_SKIP;
55	}
56
57	if (!bss[NL80211_BSS_BSSID])
58		return NL_SKIP;
59
60	if (!bss[NL80211_BSS_STATUS])
61		return NL_SKIP;
62
63	mac_addr_n2a(mac_addr, nla_data(bss[NL80211_BSS_BSSID]));
64	if_indextoname(nla_get_u32(tb[NL80211_ATTR_IFINDEX]), dev);
65
66	switch (nla_get_u32(bss[NL80211_BSS_STATUS])) {
67	case NL80211_BSS_STATUS_ASSOCIATED:
68		printf("Connected to %s (on %s)\n", mac_addr, dev);
69		break;
70	case NL80211_BSS_STATUS_AUTHENTICATED:
71		printf("Authenticated with %s (on %s)\n", mac_addr, dev);
72		return NL_SKIP;
73	case NL80211_BSS_STATUS_IBSS_JOINED:
74		printf("Joined IBSS %s (on %s)\n", mac_addr, dev);
75		break;
76	default:
77		return NL_SKIP;
78	}
79
80	result->anything_found = true;
81
82	if (bss[NL80211_BSS_INFORMATION_ELEMENTS])
83		print_ies(nla_data(bss[NL80211_BSS_INFORMATION_ELEMENTS]),
84			  nla_len(bss[NL80211_BSS_INFORMATION_ELEMENTS]),
85			  false, PRINT_LINK);
86
87	if (bss[NL80211_BSS_FREQUENCY])
88		printf("\tfreq: %d\n",
89			nla_get_u32(bss[NL80211_BSS_FREQUENCY]));
90
91	if (nla_get_u32(bss[NL80211_BSS_STATUS]) != NL80211_BSS_STATUS_ASSOCIATED)
92		return NL_SKIP;
93
94	/* only in the assoc case do we want more info from station get */
95	result->link_found = true;
96	memcpy(result->bssid, nla_data(bss[NL80211_BSS_BSSID]), 6);
97	return NL_SKIP;
98}
99
100static int handle_scan_for_link(struct nl80211_state *state,
101				struct nl_cb *cb,
102				struct nl_msg *msg,
103				int argc, char **argv,
104				enum id_input id)
105{
106	if (argc > 0)
107		return 1;
108
109	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, link_bss_handler, &lr);
110	return 0;
111}
112
113static int print_link_sta(struct nl_msg *msg, void *arg)
114{
115	struct nlattr *tb[NL80211_ATTR_MAX + 1];
116	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
117	struct nlattr *sinfo[NL80211_STA_INFO_MAX + 1];
118	struct nlattr *binfo[NL80211_STA_BSS_PARAM_MAX + 1];
119	static struct nla_policy stats_policy[NL80211_STA_INFO_MAX + 1] = {
120		[NL80211_STA_INFO_INACTIVE_TIME] = { .type = NLA_U32 },
121		[NL80211_STA_INFO_RX_BYTES] = { .type = NLA_U32 },
122		[NL80211_STA_INFO_TX_BYTES] = { .type = NLA_U32 },
123		[NL80211_STA_INFO_RX_PACKETS] = { .type = NLA_U32 },
124		[NL80211_STA_INFO_TX_PACKETS] = { .type = NLA_U32 },
125		[NL80211_STA_INFO_SIGNAL] = { .type = NLA_U8 },
126		[NL80211_STA_INFO_TX_BITRATE] = { .type = NLA_NESTED },
127		[NL80211_STA_INFO_LLID] = { .type = NLA_U16 },
128		[NL80211_STA_INFO_PLID] = { .type = NLA_U16 },
129		[NL80211_STA_INFO_PLINK_STATE] = { .type = NLA_U8 },
130	};
131	static struct nla_policy bss_policy[NL80211_STA_BSS_PARAM_MAX + 1] = {
132		[NL80211_STA_BSS_PARAM_CTS_PROT] = { .type = NLA_FLAG },
133		[NL80211_STA_BSS_PARAM_SHORT_PREAMBLE] = { .type = NLA_FLAG },
134		[NL80211_STA_BSS_PARAM_SHORT_SLOT_TIME] = { .type = NLA_FLAG },
135		[NL80211_STA_BSS_PARAM_DTIM_PERIOD] = { .type = NLA_U8 },
136		[NL80211_STA_BSS_PARAM_BEACON_INTERVAL] = { .type = NLA_U16 },
137	};
138
139	nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
140		  genlmsg_attrlen(gnlh, 0), NULL);
141
142	if (!tb[NL80211_ATTR_STA_INFO]) {
143		fprintf(stderr, "sta stats missing!\n");
144		return NL_SKIP;
145	}
146	if (nla_parse_nested(sinfo, NL80211_STA_INFO_MAX,
147			     tb[NL80211_ATTR_STA_INFO],
148			     stats_policy)) {
149		fprintf(stderr, "failed to parse nested attributes!\n");
150		return NL_SKIP;
151	}
152
153	if (sinfo[NL80211_STA_INFO_RX_BYTES] && sinfo[NL80211_STA_INFO_RX_PACKETS])
154		printf("\tRX: %u bytes (%u packets)\n",
155			nla_get_u32(sinfo[NL80211_STA_INFO_RX_BYTES]),
156			nla_get_u32(sinfo[NL80211_STA_INFO_RX_PACKETS]));
157	if (sinfo[NL80211_STA_INFO_TX_BYTES] && sinfo[NL80211_STA_INFO_TX_PACKETS])
158		printf("\tTX: %u bytes (%u packets)\n",
159			nla_get_u32(sinfo[NL80211_STA_INFO_TX_BYTES]),
160			nla_get_u32(sinfo[NL80211_STA_INFO_TX_PACKETS]));
161	if (sinfo[NL80211_STA_INFO_SIGNAL])
162		printf("\tsignal: %d dBm\n",
163			(int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL]));
164
165	if (sinfo[NL80211_STA_INFO_TX_BITRATE]) {
166		char buf[100];
167
168		parse_bitrate(sinfo[NL80211_STA_INFO_TX_BITRATE], buf, sizeof(buf));
169		printf("\ttx bitrate: %s\n", buf);
170	}
171
172	if (sinfo[NL80211_STA_INFO_BSS_PARAM]) {
173		if (nla_parse_nested(binfo, NL80211_STA_BSS_PARAM_MAX,
174				     sinfo[NL80211_STA_INFO_BSS_PARAM],
175				     bss_policy)) {
176			fprintf(stderr, "failed to parse nested bss parameters!\n");
177		} else {
178			char *delim = "";
179			printf("\n\tbss flags:\t");
180			if (binfo[NL80211_STA_BSS_PARAM_CTS_PROT]) {
181				printf("CTS-protection");
182				delim = " ";
183			}
184			if (binfo[NL80211_STA_BSS_PARAM_SHORT_PREAMBLE]) {
185				printf("%sshort-preamble", delim);
186				delim = " ";
187			}
188			if (binfo[NL80211_STA_BSS_PARAM_SHORT_SLOT_TIME])
189				printf("%sshort-slot-time", delim);
190			printf("\n\tdtim period:\t%d",
191			       nla_get_u8(binfo[NL80211_STA_BSS_PARAM_DTIM_PERIOD]));
192			printf("\n\tbeacon int:\t%d",
193			       nla_get_u16(binfo[NL80211_STA_BSS_PARAM_BEACON_INTERVAL]));
194			printf("\n");
195		}
196	}
197
198	return NL_SKIP;
199}
200
201static int handle_link_sta(struct nl80211_state *state,
202			   struct nl_cb *cb,
203			   struct nl_msg *msg,
204			   int argc, char **argv,
205			   enum id_input id)
206{
207	unsigned char mac_addr[ETH_ALEN];
208
209	if (argc < 1)
210		return 1;
211
212	if (mac_addr_a2n(mac_addr, argv[0])) {
213		fprintf(stderr, "invalid mac address\n");
214		return 2;
215	}
216
217	argc--;
218	argv++;
219
220	if (argc)
221		return 1;
222
223	NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr);
224
225	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, print_link_sta, NULL);
226
227	return 0;
228 nla_put_failure:
229	return -ENOBUFS;
230}
231
232static int handle_link(struct nl80211_state *state, struct nl_cb *cb,
233		       struct nl_msg *msg, int argc, char **argv,
234		       enum id_input id)
235{
236	char *link_argv[] = {
237		NULL,
238		"link",
239		"get_bss",
240		NULL,
241	};
242	char *station_argv[] = {
243		NULL,
244		"link",
245		"get_sta",
246		NULL,
247		NULL,
248	};
249	char bssid_buf[3*6];
250	int err;
251
252	link_argv[0] = argv[0];
253	err = handle_cmd(state, id, 3, link_argv);
254	if (err)
255		return err;
256
257	if (!lr.link_found) {
258		if (!lr.anything_found)
259			printf("Not connected.\n");
260		return 0;
261	}
262
263	mac_addr_n2a(bssid_buf, lr.bssid);
264	bssid_buf[17] = '\0';
265
266	station_argv[0] = argv[0];
267	station_argv[3] = bssid_buf;
268	return handle_cmd(state, id, 4, station_argv);
269}
270TOPLEVEL(link, NULL, 0, 0, CIB_NETDEV, handle_link,
271	 "Print information about the current link, if any.");
272HIDDEN(link, get_sta, "", NL80211_CMD_GET_STATION, 0,
273	CIB_NETDEV, handle_link_sta);
274HIDDEN(link, get_bss, NULL, NL80211_CMD_GET_SCAN, NLM_F_DUMP,
275	CIB_NETDEV, handle_scan_for_link);
276