Print NL80211_BSS_LAST_SEEN_BOOTTIME and beacon tsf

Commit Message

Ningyuan Wang July 26, 2017, 12:01 a.m. UTC

This patch allows iw to print NL80211_BSS_LAST_SEEN_BOOTTIME
values on scan results.

Signed-off-by: Ningyuan Wang <[e-mail]>
---
 nl80211.h |  4 ++++
 scan.c    | 19 +++++++++++++++++++
 2 files changed, 23 insertions(+)

Comments

Johannes Berg Sept. 6, 2017, 10:36 a.m. UTC | #1

Hi,

>  nl80211.h |  4 ++++

Please don't include nl80211.h changes, I'll update that as needed.

> +	if (bss[NL80211_BSS_BEACON_TSF]) {
> +		unsigned long long tsf;
> +		tsf = (unsigned long
> long)nla_get_u64(bss[NL80211_BSS_BEACON_TSF]);
> +		printf("\tBeacon TSF: %llu usec (%llud,
> %.2lld:%.2llu:%.2llu)\n",
> +			tsf, tsf/1000/1000/60/60/24,
> (tsf/1000/1000/60/60) % 24,
> +			(tsf/1000/1000/60) % 60, (tsf/1000/1000) %
> 60);
> +	}

This seems fine, but we already print the BSS_TSF - is it really
needed? Anyway, I think it's OK, just not sure there's much point.

> +	if (bss[NL80211_BSS_LAST_SEEN_BOOTTIME]) {
> +		unsigned long long last_seen_since_boot;
> +		last_seen_since_boot =
> +			(unsigned long
> long)nla_get_u64(bss[NL80211_BSS_LAST_SEEN_BOOTTIME]);
> +		printf("\tlast seen since boot time: %llu usec
> (%llud, %.2lld:%.2llu:%.2llu)\n",
> +			last_seen_since_boot, last_seen_since_boot
> /1000/1000/1000/60/60/24,
> +			(last_seen_since_boot /1000/1000/1000/60/60)
> % 24,
> +			(last_seen_since_boot/1000/1000/1000/60) %
> 60,
> +			(last_seen_since_boot/1000/1000/1000) % 60);
> +	}

This is wrong - the value isn't "last seen since boot", it's "last seen
*at* boottime X" - but "boottime" maybe some kind of strange concept,
so I don't think printing this to a user makes a lot of sense at all?

johannes

Patch

diff --git a/nl80211.h b/nl80211.h
index 241220c..5ea103c 100644
--- a/nl80211.h
+++ b/nl80211.h
@@ -3360,6 +3360,9 @@  enum nl80211_bss_scan_width {
  *	(not present if no beacon frame has been received yet)
  * @NL80211_BSS_PRESP_DATA: the data in @NL80211_BSS_INFORMATION_ELEMENTS and
  *	@NL80211_BSS_TSF is known to be from a probe response (flag attribute)
+ * @NL80211_BSS_LAST_SEEN_BOOTTIME: CLOCK_BOOTTIME timestamp when this entry
+ *	was last updated by a received frame. The value is expected to be
+ *	accurate to about 10ms. (u64, nanoseconds)
  * @__NL80211_BSS_AFTER_LAST: internal
  * @NL80211_BSS_MAX: highest BSS attribute
  */
@@ -3379,6 +3382,7 @@  enum nl80211_bss {
 	NL80211_BSS_CHAN_WIDTH,
 	NL80211_BSS_BEACON_TSF,
 	NL80211_BSS_PRESP_DATA,
+	NL80211_BSS_LAST_SEEN_BOOTTIME,
 
 	/* keep last */
 	__NL80211_BSS_AFTER_LAST,
diff --git a/scan.c b/scan.c
index bf39f34..6646732 100644
--- a/scan.c
+++ b/scan.c
@@ -1853,6 +1853,8 @@  static int print_bss_handler(struct nl_msg *msg, void *arg)
 	char mac_addr[20], dev[20];
 	static struct nla_policy bss_policy[NL80211_BSS_MAX + 1] = {
 		[NL80211_BSS_TSF] = { .type = NLA_U64 },
+		[NL80211_BSS_BEACON_TSF] = { .type = NLA_U64 },
+		[NL80211_BSS_LAST_SEEN_BOOTTIME] = { .type = NLA_U64 },
 		[NL80211_BSS_FREQUENCY] = { .type = NLA_U32 },
 		[NL80211_BSS_BSSID] = { },
 		[NL80211_BSS_BEACON_INTERVAL] = { .type = NLA_U16 },
@@ -1918,6 +1920,23 @@  static int print_bss_handler(struct nl_msg *msg, void *arg)
 			tsf, tsf/1000/1000/60/60/24, (tsf/1000/1000/60/60) % 24,
 			(tsf/1000/1000/60) % 60, (tsf/1000/1000) % 60);
 	}
+	if (bss[NL80211_BSS_BEACON_TSF]) {
+		unsigned long long tsf;
+		tsf = (unsigned long long)nla_get_u64(bss[NL80211_BSS_BEACON_TSF]);
+		printf("\tBeacon TSF: %llu usec (%llud, %.2lld:%.2llu:%.2llu)\n",
+			tsf, tsf/1000/1000/60/60/24, (tsf/1000/1000/60/60) % 24,
+			(tsf/1000/1000/60) % 60, (tsf/1000/1000) % 60);
+	}
+	if (bss[NL80211_BSS_LAST_SEEN_BOOTTIME]) {
+		unsigned long long last_seen_since_boot;
+		last_seen_since_boot =
+			(unsigned long long)nla_get_u64(bss[NL80211_BSS_LAST_SEEN_BOOTTIME]);
+		printf("\tlast seen since boot time: %llu usec (%llud, %.2lld:%.2llu:%.2llu)\n",
+			last_seen_since_boot, last_seen_since_boot /1000/1000/1000/60/60/24,
+			(last_seen_since_boot /1000/1000/1000/60/60) % 24,
+			(last_seen_since_boot/1000/1000/1000/60) % 60,
+			(last_seen_since_boot/1000/1000/1000) % 60);
+	}
 	if (bss[NL80211_BSS_FREQUENCY]) {
 		int freq = nla_get_u32(bss[NL80211_BSS_FREQUENCY]);
 		printf("\tfreq: %d\n", freq);