nexmon – Rev 1
?pathlinks?
#include <net/if.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <stdbool.h>
#include <netlink/genl/genl.h>
#include <netlink/genl/family.h>
#include <netlink/genl/ctrl.h>
#include <netlink/msg.h>
#include <netlink/attr.h>
#include "nl80211.h"
#include "iw.h"
struct link_result {
uint8_t bssid[8];
bool link_found;
bool anything_found;
};
static struct link_result lr = { .link_found = false };
static int link_bss_handler(struct nl_msg *msg, void *arg)
{
struct nlattr *tb[NL80211_ATTR_MAX + 1];
struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
struct nlattr *bss[NL80211_BSS_MAX + 1];
static struct nla_policy bss_policy[NL80211_BSS_MAX + 1] = {
[NL80211_BSS_TSF] = { .type = NLA_U64 },
[NL80211_BSS_FREQUENCY] = { .type = NLA_U32 },
[NL80211_BSS_BSSID] = { },
[NL80211_BSS_BEACON_INTERVAL] = { .type = NLA_U16 },
[NL80211_BSS_CAPABILITY] = { .type = NLA_U16 },
[NL80211_BSS_INFORMATION_ELEMENTS] = { },
[NL80211_BSS_SIGNAL_MBM] = { .type = NLA_U32 },
[NL80211_BSS_SIGNAL_UNSPEC] = { .type = NLA_U8 },
[NL80211_BSS_STATUS] = { .type = NLA_U32 },
};
struct link_result *result = arg;
char mac_addr[20], dev[20];
nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
genlmsg_attrlen(gnlh, 0), NULL);
if (!tb[NL80211_ATTR_BSS]) {
fprintf(stderr, "bss info missing!\n");
return NL_SKIP;
}
if (nla_parse_nested(bss, NL80211_BSS_MAX,
tb[NL80211_ATTR_BSS],
bss_policy)) {
fprintf(stderr, "failed to parse nested attributes!\n");
return NL_SKIP;
}
if (!bss[NL80211_BSS_BSSID])
return NL_SKIP;
if (!bss[NL80211_BSS_STATUS])
return NL_SKIP;
mac_addr_n2a(mac_addr, nla_data(bss[NL80211_BSS_BSSID]));
if_indextoname(nla_get_u32(tb[NL80211_ATTR_IFINDEX]), dev);
switch (nla_get_u32(bss[NL80211_BSS_STATUS])) {
case NL80211_BSS_STATUS_ASSOCIATED:
printf("Connected to %s (on %s)\n", mac_addr, dev);
break;
case NL80211_BSS_STATUS_AUTHENTICATED:
printf("Authenticated with %s (on %s)\n", mac_addr, dev);
return NL_SKIP;
case NL80211_BSS_STATUS_IBSS_JOINED:
printf("Joined IBSS %s (on %s)\n", mac_addr, dev);
break;
default:
return NL_SKIP;
}
result->anything_found = true;
if (bss[NL80211_BSS_INFORMATION_ELEMENTS])
print_ies(nla_data(bss[NL80211_BSS_INFORMATION_ELEMENTS]),
nla_len(bss[NL80211_BSS_INFORMATION_ELEMENTS]),
false, PRINT_LINK);
if (bss[NL80211_BSS_FREQUENCY])
printf("\tfreq: %d\n",
nla_get_u32(bss[NL80211_BSS_FREQUENCY]));
if (nla_get_u32(bss[NL80211_BSS_STATUS]) != NL80211_BSS_STATUS_ASSOCIATED)
return NL_SKIP;
/* only in the assoc case do we want more info from station get */
result->link_found = true;
memcpy(result->bssid, nla_data(bss[NL80211_BSS_BSSID]), 6);
return NL_SKIP;
}
static int handle_scan_for_link(struct nl80211_state *state,
struct nl_cb *cb,
struct nl_msg *msg,
int argc, char **argv,
enum id_input id)
{
if (argc > 0)
return 1;
nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, link_bss_handler, &lr);
return 0;
}
static int print_link_sta(struct nl_msg *msg, void *arg)
{
struct nlattr *tb[NL80211_ATTR_MAX + 1];
struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
struct nlattr *sinfo[NL80211_STA_INFO_MAX + 1];
struct nlattr *binfo[NL80211_STA_BSS_PARAM_MAX + 1];
static struct nla_policy stats_policy[NL80211_STA_INFO_MAX + 1] = {
[NL80211_STA_INFO_INACTIVE_TIME] = { .type = NLA_U32 },
[NL80211_STA_INFO_RX_BYTES] = { .type = NLA_U32 },
[NL80211_STA_INFO_TX_BYTES] = { .type = NLA_U32 },
[NL80211_STA_INFO_RX_PACKETS] = { .type = NLA_U32 },
[NL80211_STA_INFO_TX_PACKETS] = { .type = NLA_U32 },
[NL80211_STA_INFO_SIGNAL] = { .type = NLA_U8 },
[NL80211_STA_INFO_TX_BITRATE] = { .type = NLA_NESTED },
[NL80211_STA_INFO_LLID] = { .type = NLA_U16 },
[NL80211_STA_INFO_PLID] = { .type = NLA_U16 },
[NL80211_STA_INFO_PLINK_STATE] = { .type = NLA_U8 },
};
static struct nla_policy bss_policy[NL80211_STA_BSS_PARAM_MAX + 1] = {
[NL80211_STA_BSS_PARAM_CTS_PROT] = { .type = NLA_FLAG },
[NL80211_STA_BSS_PARAM_SHORT_PREAMBLE] = { .type = NLA_FLAG },
[NL80211_STA_BSS_PARAM_SHORT_SLOT_TIME] = { .type = NLA_FLAG },
[NL80211_STA_BSS_PARAM_DTIM_PERIOD] = { .type = NLA_U8 },
[NL80211_STA_BSS_PARAM_BEACON_INTERVAL] = { .type = NLA_U16 },
};
nla_parse(tb, NL80211_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
genlmsg_attrlen(gnlh, 0), NULL);
if (!tb[NL80211_ATTR_STA_INFO]) {
fprintf(stderr, "sta stats missing!\n");
return NL_SKIP;
}
if (nla_parse_nested(sinfo, NL80211_STA_INFO_MAX,
tb[NL80211_ATTR_STA_INFO],
stats_policy)) {
fprintf(stderr, "failed to parse nested attributes!\n");
return NL_SKIP;
}
if (sinfo[NL80211_STA_INFO_RX_BYTES] && sinfo[NL80211_STA_INFO_RX_PACKETS])
printf("\tRX: %u bytes (%u packets)\n",
nla_get_u32(sinfo[NL80211_STA_INFO_RX_BYTES]),
nla_get_u32(sinfo[NL80211_STA_INFO_RX_PACKETS]));
if (sinfo[NL80211_STA_INFO_TX_BYTES] && sinfo[NL80211_STA_INFO_TX_PACKETS])
printf("\tTX: %u bytes (%u packets)\n",
nla_get_u32(sinfo[NL80211_STA_INFO_TX_BYTES]),
nla_get_u32(sinfo[NL80211_STA_INFO_TX_PACKETS]));
if (sinfo[NL80211_STA_INFO_SIGNAL])
printf("\tsignal: %d dBm\n",
(int8_t)nla_get_u8(sinfo[NL80211_STA_INFO_SIGNAL]));
if (sinfo[NL80211_STA_INFO_TX_BITRATE]) {
char buf[100];
parse_bitrate(sinfo[NL80211_STA_INFO_TX_BITRATE], buf, sizeof(buf));
printf("\ttx bitrate: %s\n", buf);
}
if (sinfo[NL80211_STA_INFO_BSS_PARAM]) {
if (nla_parse_nested(binfo, NL80211_STA_BSS_PARAM_MAX,
sinfo[NL80211_STA_INFO_BSS_PARAM],
bss_policy)) {
fprintf(stderr, "failed to parse nested bss parameters!\n");
} else {
char *delim = "";
printf("\n\tbss flags:\t");
if (binfo[NL80211_STA_BSS_PARAM_CTS_PROT]) {
printf("CTS-protection");
delim = " ";
}
if (binfo[NL80211_STA_BSS_PARAM_SHORT_PREAMBLE]) {
printf("%sshort-preamble", delim);
delim = " ";
}
if (binfo[NL80211_STA_BSS_PARAM_SHORT_SLOT_TIME])
printf("%sshort-slot-time", delim);
printf("\n\tdtim period:\t%d",
nla_get_u8(binfo[NL80211_STA_BSS_PARAM_DTIM_PERIOD]));
printf("\n\tbeacon int:\t%d",
nla_get_u16(binfo[NL80211_STA_BSS_PARAM_BEACON_INTERVAL]));
printf("\n");
}
}
return NL_SKIP;
}
static int handle_link_sta(struct nl80211_state *state,
struct nl_cb *cb,
struct nl_msg *msg,
int argc, char **argv,
enum id_input id)
{
unsigned char mac_addr[ETH_ALEN];
if (argc < 1)
return 1;
if (mac_addr_a2n(mac_addr, argv[0])) {
fprintf(stderr, "invalid mac address\n");
return 2;
}
argc--;
argv++;
if (argc)
return 1;
NLA_PUT(msg, NL80211_ATTR_MAC, ETH_ALEN, mac_addr);
nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, print_link_sta, NULL);
return 0;
nla_put_failure:
return -ENOBUFS;
}
static int handle_link(struct nl80211_state *state, struct nl_cb *cb,
struct nl_msg *msg, int argc, char **argv,
enum id_input id)
{
char *link_argv[] = {
NULL,
"link",
"get_bss",
NULL,
};
char *station_argv[] = {
NULL,
"link",
"get_sta",
NULL,
NULL,
};
char bssid_buf[3*6];
int err;
link_argv[0] = argv[0];
err = handle_cmd(state, id, 3, link_argv);
if (err)
return err;
if (!lr.link_found) {
if (!lr.anything_found)
printf("Not connected.\n");
return 0;
}
mac_addr_n2a(bssid_buf, lr.bssid);
bssid_buf[17] = '\0';
station_argv[0] = argv[0];
station_argv[3] = bssid_buf;
return handle_cmd(state, id, 4, station_argv);
}
TOPLEVEL(link, NULL, 0, 0, CIB_NETDEV, handle_link,
"Print information about the current link, if any.");
HIDDEN(link, get_sta, "", NL80211_CMD_GET_STATION, 0,
CIB_NETDEV, handle_link_sta);
HIDDEN(link, get_bss, NULL, NL80211_CMD_GET_SCAN, NLM_F_DUMP,
CIB_NETDEV, handle_scan_for_link);