contrib/package: add freifunk watchdog daemon

1 files changed, 347 insertions, 0 deletions

diff --git a/contrib/package/freifunk-watchdog/src/watchdog.c b/contrib/package/freifunk-watchdog/src/watchdog.c
new file mode 100644
index 000000000..aea051681
--- /dev/null
+++ b/contrib/package/freifunk-watchdog/src/watchdog.c
@@ -0,0 +1,347 @@
+/*
+ *   This program is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+ *
+ *   Copyright (C) 2009 Jo-Philipp Wich <xm@subsignal.org>
+ */
+
+#include "watchdog.h"
+
+/* Get BSSID of given interface */
+static int iw_get_bssid(int iwfd, const char *ifname, char *bssid)
+{
+	struct iwreq iwrq;
+
+	if( iw_ioctl(iwfd, ifname, SIOCGIWAP, &iwrq) >= 0 )
+	{
+		unsigned char *addr = (unsigned char *)iwrq.u.ap_addr.sa_data;
+
+		sprintf(bssid, "%02X:%02X:%02X:%02X:%02X:%02X",
+			addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
+
+		return 0;
+	}
+
+	return -1;
+}
+
+/* Get channel of given interface */
+static int iw_get_channel(int iwfd, const char *ifname, int *channel)
+{
+	int i;
+	char buffer[sizeof(struct iw_range)];
+	double cur_freq, cmp_freq;
+	struct iwreq iwrq;
+	struct iw_range *range;
+
+	memset(buffer, 0, sizeof(buffer));
+
+	iwrq.u.data.pointer = (char *)buffer;
+	iwrq.u.data.length = sizeof(buffer);
+	iwrq.u.data.flags = 0;
+
+	if( iw_ioctl(iwfd, ifname, SIOCGIWRANGE, &iwrq) < 0)
+	{
+		*channel = -1;
+		return -1;
+	}
+
+	range = (struct iw_range *)buffer;
+
+	if( iw_ioctl(iwfd, ifname, SIOCGIWFREQ, &iwrq) >= 0 )
+	{
+		cur_freq = ((double)iwrq.u.freq.m) * pow(10, iwrq.u.freq.e);
+		if( cur_freq < 1000.00 )
+		{
+			*channel = (int)cur_freq;
+			return 0;
+		}
+
+		for(i = 0; i < range->num_frequency; i++)
+	    {
+			cmp_freq = ((double)range->freq[i].m) * pow(10, range->freq[i].e);
+			if( cmp_freq == cur_freq )
+			{
+				*channel = (int)range->freq[i].i;
+				return 0;
+			}
+		}
+	}
+
+	*channel = -1;
+	return -1;
+}
+
+/* Get the (first) pid of given process name */
+static int find_process(const char *name)
+{
+	int pid = -1;
+	int file;
+	char buffer[128];
+	char cmpname[128];
+	DIR *dir;
+	struct dirent *entry;
+
+	if( (dir = opendir("/proc")) != NULL )
+	{
+		snprintf(cmpname, sizeof(cmpname), "Name:\t%s\n", name);
+
+		while( (entry = readdir(dir)) != NULL )
+		{
+			if( !strcmp(entry->d_name, "..") || !isdigit(*entry->d_name) )
+				continue;
+
+			sprintf(buffer, "/proc/%s/status", entry->d_name);
+			if( (file = open(buffer, O_RDONLY)) > -1 )
+			{
+				read(file, buffer, sizeof(buffer));
+				close(file);
+
+				if( strstr(buffer, cmpname) == buffer )
+				{
+					pid = atoi(entry->d_name);
+					break;
+				}
+			}
+		}
+
+		closedir(dir);
+		return pid;
+	}
+
+	syslog(LOG_CRIT, "Unable to open /proc: %s",
+		strerror(errno));
+
+	return -1;
+}
+
+/* Check if given uci file was updated */
+static int check_uci_update(const char *config, time_t *mtime)
+{
+	struct stat s;
+	char path[128];
+
+	snprintf(path, sizeof(path), "/etc/config/%s", config);
+	if( stat(path, &s) > -1 )
+	{
+		if( (*mtime == 0) || (s.st_mtime > *mtime) )
+		{
+			*mtime = s.st_mtime;
+			return 1;
+		}
+		else
+		{
+			snprintf(path, sizeof(path), "/var/state/%s", config);
+			if( stat(path, &s) > -1 )
+			{
+				if( (*mtime == 0) || (s.st_mtime > *mtime) )
+				{
+					*mtime = s.st_mtime;
+					return 1;
+				}
+			}
+
+			return 0;
+		}
+	}
+
+	return -1;
+}
+
+/* Add tuple */
+static void load_wifi_uci_add_iface(const char *section, struct uci_itr_ctx *itr)
+{
+	wifi_tuple_t *t;
+	const char *ucitmp;
+	int val = 0;
+
+	if( (t = (wifi_tuple_t *)malloc(sizeof(wifi_tuple_t))) != NULL )
+	{
+		ucitmp = ucix_get_option(itr->ctx, "wireless", section, "ifname");
+		if(ucitmp)
+		{
+			strncpy(t->ifname, ucitmp, sizeof(t->ifname));
+			val++;
+		}
+
+		ucitmp = ucix_get_option(itr->ctx, "wireless", section, "bssid");
+		if(ucitmp)
+		{
+			strncpy(t->bssid, ucitmp, sizeof(t->bssid));
+			val++;
+		}
+
+		ucitmp = ucix_get_option(itr->ctx, "wireless", section, "device");
+		if(ucitmp)
+		{
+			ucitmp = ucix_get_option(itr->ctx, "wireless", ucitmp, "channel");
+			if(ucitmp)
+			{
+				t->channel = atoi(ucitmp);
+				val++;
+			}
+		}
+	
+		if( val == 3 )
+		{
+			syslog(LOG_INFO, "Monitoring %s: bssid=%s channel=%d",
+				t->ifname, t->bssid, t->channel);
+
+			t->next = itr->list;
+			itr->list = t;
+		}
+		else
+		{
+			free(t);
+		}
+	}
+}
+
+/* Load config */
+static wifi_tuple_t * load_wifi_uci(wifi_tuple_t *ifs, time_t *modtime)
+{
+	struct uci_context *ctx;
+	struct uci_itr_ctx itr;
+	wifi_tuple_t *cur, *next;
+
+	if( check_uci_update("wireless", modtime) )
+	{
+		syslog(LOG_INFO, "Config changed, reloading");
+
+		if( (ctx = ucix_init("wireless")) != NULL )
+		{
+			if( ifs != NULL )
+			{
+				for(cur = ifs; cur; cur = next)
+				{
+					next = cur->next;
+					free(cur);
+				}
+			}
+
+			itr.list = NULL;
+			itr.ctx = ctx;
+
+			ucix_for_each_section_type(ctx, "wireless", "wifi-iface",
+				(void *)load_wifi_uci_add_iface, &itr);
+
+			return itr.list;
+		}
+	}
+
+	return ifs;
+}
+
+/* Daemon implementation */
+static int do_daemon(void)
+{
+	int iwfd;
+	int channel;
+	char bssid[18];
+
+	wifi_tuple_t *ifs = NULL, *curif;
+	time_t modtime = 0;
+
+	int restart_wifi = 0;
+	int restart_cron = 0;
+
+	openlog(SYSLOG_IDENT, 0, LOG_DAEMON);
+	//daemon(1, 1);
+
+	if( (iwfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1 )
+	{
+		perror("Can not open wireless control socket");
+		return 1;
+	}
+
+	while( 1 )
+	{
+		if( (ifs = load_wifi_uci(ifs, &modtime)) == NULL )
+		{
+			printf("Can not load wireless uci. File corrupt?\n");
+			return 1;
+		}
+
+		/* Check crond */
+		if( find_process("crond") < 0 )
+		{
+			syslog(LOG_WARNING, "The crond process died, restarting");
+			restart_cron++;		
+		}
+
+		/* Check wireless interfaces */
+		for( curif = ifs; curif; curif = curif->next )
+		{
+			/* Get current channel and bssid */
+			if( (iw_get_bssid(iwfd, curif->ifname, bssid) == 0) &&
+			    (iw_get_channel(iwfd, curif->ifname, &channel) == 0) )
+			{
+				/* Check BSSID */
+				if( strcasecmp(bssid, curif->bssid) != 0 )
+				{
+					syslog(LOG_WARNING, "BSSID mismatch on %s: current=%s wanted=%s",
+						curif->ifname, bssid, curif->bssid);
+
+					restart_wifi++;
+				}
+
+				/* Check channel */
+				if( channel != curif->channel )
+				{
+					syslog(LOG_WARNING, "Channel mismatch on %s: current=%d wanted=%d",
+						curif->ifname, channel, curif->channel);
+
+					restart_wifi++;
+				}
+			}
+			else
+			{
+				syslog(LOG_WARNING, "Requested interface %s not present", curif->ifname);				
+			}
+		}
+
+
+		/* Wifi restart required? */
+		if( restart_wifi > 0 )
+		{
+			restart_wifi = 0;
+			EXEC(WIFI_ACTION);
+		}
+
+		/* Cron restart required? */
+		if( restart_cron > 0 )
+		{
+			restart_cron = 0;
+			EXEC(CRON_ACTION);	
+		}
+
+		sleep(INTERVAL);
+	}
+
+	closelog();
+	return 0;
+}
+
+
+int main(int argc, char *argv[])
+{
+	/* Check if watchdog is running ... */
+	if( (argc > 1) && (strcmp(argv[1], "running") == 0) )
+	{
+		return (find_process(BINARY) >= 0);
+	}
+
+	/* Start daemon */
+	return do_daemon();
+}