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#include <arpa/inet.h>
#include <linux/rtnetlink.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ev.h>
#include "list.h"
#include "log.h"
#include "pingu_burst.h"
#include "pingu_host.h"
#include "pingu_iface.h"
#include "pingu_ping.h"
#include "xlib.h"
static struct list_head host_list = LIST_INITIALIZER(host_list);
float default_burst_interval = 30.0;
float default_timeout = 1.0;
int default_max_retries = 5;
int default_required_replies = 2;
char *default_up_action = NULL;
char *default_down_action = NULL;
char *default_route_script = NULL;
int default_route_table = 10;
/* note: this overwrite the line buffer */
static void parse_line(char *line, char **key, char **value)
{
char *p;
/* strip comments and trailng \n */
p = strpbrk(line, "#\n");
if (p)
*p = '\0';
(*value) = NULL;
if (line[0] == '\0') {
(*key) = NULL;
return;
}
/* skip leading whitespace */
while (isspace(*p)) {
if (*p == '\0')
return;
p++;
}
(*key) = line;
/* find space between keyword and value */
p = line;
while (!isspace(*p)) {
if (*p == '\0')
return;
p++;
}
*p++ = '\0';
/* find value */
while (isspace(*p)) {
if (*p == '\0')
return;
p++;
}
(*value) = p;
}
int pingu_host_read_config(const char *file)
{
FILE *f = fopen(file, "r");
struct pingu_host *p = NULL;
int lineno = 0;
char line[256];
if (f == NULL) {
log_perror(file);
return -1;
}
while (fgets(line, sizeof(line), f)) {
char *key, *value;
lineno++;
parse_line(line, &key, &value);
if (key == NULL)
continue;
if (strcmp(key, "host") == 0) {
p = xmalloc(sizeof(struct pingu_host));
memset(p, 0, sizeof(struct pingu_host));
p->host = xstrdup(value);
p->gateway = xstrdup(value);
p->status = 1; /* online by default */
p->max_retries = default_max_retries;
p->timeout = default_timeout;
p->up_action = default_up_action;
p->down_action = default_down_action;
p->required_replies = default_required_replies;
p->burst_interval = default_burst_interval;
list_add(&p->host_list_entry, &host_list);
continue;
}
if (p == NULL) {
if (strcmp(key, "interval") == 0) {
default_burst_interval = atof(value);
} else if (strcmp(key, "retry") == 0) {
default_max_retries = atoi(value);
} else if (strcmp(key, "required") == 0) {
default_required_replies = atoi(value);
} else if (strcmp(key, "timeout") == 0) {
default_timeout = atof(value);
} else if (strcmp(key, "up-action") == 0) {
default_up_action = xstrdup(value);
} else if (strcmp(key, "down-action") == 0) {
default_down_action = xstrdup(value);
} else if (strcmp(key, "route-script") == 0) {
default_route_script = xstrdup(value);
} else if (strcmp(key, "route-table") == 0) {
default_route_table = atoi(value);
} else
log_error("host not specified");
} else if (strcmp(key, "interface") == 0) {
p->interface = xstrdup(value);
} else if (strcmp(key, "gateway") == 0) {
if (p->gateway)
free(p->gateway);
p->gateway = xstrdup(value);
} else if ((strcmp(key, "name") == 0) || (strcmp(key, "label") == 0)) {
p->label = xstrdup(value);
} else if (strcmp(key, "up-action") == 0) {
p->up_action = xstrdup(value);
} else if (strcmp(key, "down-action") == 0) {
p->down_action = xstrdup(value);
} else if (strcmp(key, "retry") == 0) {
p->max_retries = atoi(value);
} else if (strcmp(key, "required") == 0) {
p->required_replies = atoi(value);
} else if (strcmp(key, "timeout") == 0) {
p->timeout = atof(value);
} else if (strcmp(key, "source-ip") == 0) {
p->source_ip = xstrdup(value);
} else if (strcmp(key, "interval") == 0) {
p->burst_interval = atof(value);
} else if (strcmp(key, "route-table") == 0) {
p->iface_route_table = atoi(value);
} else {
log_error("Unknown keyword '%s' on line %i", key,
lineno);
}
}
return 0;
}
static char *get_provider_gateway(struct pingu_host *p)
{
if (p->gateway != NULL)
return p->gateway;
return p->host;
}
static void exec_route_change_hook(void)
{
struct pingu_host *host;
struct list_head *n;
char **args;
int i = 0;
pid_t pid;
if (default_route_script == NULL)
return;
list_for_each(n, &host_list)
i++;
args = malloc(sizeof(char *) * (i + 2));
if (args == NULL) {
log_perror("malloc");
return;
}
i = 0;
args[i++] = default_route_script;
list_for_each_entry(host, &host_list, host_list_entry) {
if (host->status)
args[i++] = get_provider_gateway(host);
}
args[i] = NULL;
pid = fork();
if (pid < 0) {
log_perror("fork");
free(args);
return;
}
if (pid == 0) {
/* the child */
execvp(default_route_script, args);
log_perror(args[0]);
exit(1);
}
/* libev reaps all children */
}
static void execute_action(const char *action)
{
pid_t pid;
const char *shell = getenv("SHELL");
if (shell == NULL)
shell = "/bin/sh";
log_debug("executing '%s'", action);
pid = fork();
if (pid < 0) {
log_perror("fork");
return;
}
if (pid == 0) {
execl(shell, shell, "-c", action, NULL);
log_perror(action);
exit(1);
}
}
int pingu_host_set_status(struct pingu_host *host, int status)
{
const char *action;
int route_action = 0;
host->burst.active = 0;
if (host->status == status) {
log_debug("%s: %s: status is still %i",
host->iface->name, host->host, status);
return status;
}
host->status = status;
log_info("%s: %s: new status: %i",
host->iface->name, host->host, status);
switch (host->status) {
case 0:
action = host->down_action;
route_action = RTM_DELROUTE;
break;
case 1:
action = host->up_action;
route_action = RTM_NEWROUTE;
break;
}
if (action != NULL)
execute_action(action);
pingu_iface_update_routes(host->iface, route_action);
exec_route_change_hook();
return status;
}
int pingu_host_verify_status(struct ev_loop *loop, struct pingu_host *host)
{
if (host->burst.pings_replied >= host->required_replies) {
pingu_host_set_status(host, 1);
} else if (host->burst.pings_sent >= host->max_retries) {
pingu_host_set_status(host, 0);
} else
pingu_ping_send(loop, host, 1);
return 0;
}
int pingu_host_init(struct ev_loop *loop, const char *config)
{
struct pingu_host *host;
if (pingu_host_read_config(config) < 0)
return -1;
if (pingu_iface_init(loop, &host_list) < 0)
return -1;
list_for_each_entry(host, &host_list, host_list_entry) {
ev_timer_init(&host->burst_timeout_watcher,
pingu_burst_timeout_cb, 0, host->burst_interval);
ev_timer_start(loop, &host->burst_timeout_watcher);
}
return 0;
}
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