/* l2tpns plugin control */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <signal.h>
#include "l2tpns.h"
#include "control.h"
struct {
char *command;
char *usage;
int action;
} builtins[] = {
{ "load_plugin", " PLUGIN Load named plugin", NSCTL_REQ_LOAD },
{ "unload_plugin", " PLUGIN Unload named plugin", NSCTL_REQ_UNLOAD },
{ "help", " List available commands", NSCTL_REQ_HELP },
{ 0 }
};
static int debug = 0;
static int timeout = 2; // 2 seconds
static char *me;
#define USAGE() fprintf(stderr, "Usage: %s [-d] [-h HOST[:PORT]] [-t TIMEOUT] COMMAND [ARG ...]\n", me)
static struct nsctl *request(char *host, int port, int type, int argc, char *argv[]);
int main(int argc, char *argv[])
{
int req_type = 0;
char *host = 0;
int port;
int i;
char *p;
struct nsctl *res;
if ((p = strrchr((me = argv[0]), '/')))
me = p + 1;
opterr = 0;
while ((i = getopt(argc, argv, "dh:t:")) != -1)
switch (i)
{
case 'd':
debug++;
break;
case 'h':
host = optarg;
break;
case 't':
timeout = atoi(optarg);
break;
default:
USAGE();
return EXIT_FAILURE;
}
argc -= optind;
argv += optind;
if (argc < 1 || !argv[0][0])
{
USAGE();
return EXIT_FAILURE;
}
if (!host)
host = "127.0.0.1";
if ((p = strchr(host, ':')))
{
port = atoi(p + 1);
if (!port)
{
fprintf(stderr, "%s: invalid port `%s'\n", me, p + 1);
return EXIT_FAILURE;
}
*p = 0;
}
else
{
port = NSCTL_PORT;
}
for (i = 0; !req_type && builtins[i].command; i++)
if (!strcmp(argv[0], builtins[i].command))
req_type = builtins[i].action;
if (req_type == NSCTL_REQ_HELP)
{
printf("Available commands:\n");
for (i = 0; builtins[i].command; i++)
printf(" %s%s\n", builtins[i].command, builtins[i].usage);
}
if (req_type)
{
argc--;
argv++;
}
else
{
req_type = NSCTL_REQ_CONTROL;
}
if ((res = request(host, port, req_type, argc, argv)))
{
FILE *stream = stderr;
int status = EXIT_FAILURE;
if (res->type == NSCTL_RES_OK)
{
stream = stdout;
status = EXIT_SUCCESS;
}
for (i = 0; i < res->argc; i++)
fprintf(stream, "%s\n", res->argv[i]);
return status;
}
return EXIT_FAILURE;
}
static void sigalrm_handler(int sig) { }
static struct nsctl *request(char *host, int port, int type, int argc, char *argv[])
{
static struct nsctl res;
struct sockaddr_in peer;
socklen_t len = sizeof(peer);
struct hostent *h = gethostbyname(host);
int fd;
char buf[NSCTL_MAX_PKT_SZ];
int sz;
char *err;
if (!h || h->h_addrtype != AF_INET)
{
fprintf(stderr, "%s: invalid host `%s'\n", me, host);
return 0;
}
if ((fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
{
fprintf(stderr, "%s: can't create udp socket (%s)\n", me, strerror(errno));
return 0;
}
memset(&peer, 0, len);
peer.sin_family = AF_INET;
peer.sin_port = htons(port);
memcpy(&peer.sin_addr.s_addr, h->h_addr, sizeof(peer.sin_addr.s_addr));
if (connect(fd, (struct sockaddr *) &peer, sizeof(peer)) < 0)
{
fprintf(stderr, "%s: udp connect failed (%s)\n", me, strerror(errno));
return 0;
}
if ((sz = pack_control(buf, sizeof(buf), type, argc, argv)) < 0)
{
fprintf(stderr, "%s: error packing request\n", me);
return 0;
}
if (debug)
{
struct nsctl req;
if (unpack_control(&req, buf, sz) == type)
{
fprintf(stderr, "Sending ");
dump_control(&req, stderr);
}
}
if (send(fd, buf, sz, 0) < 0)
{
fprintf(stderr, "%s: error sending request (%s)\n", me, strerror(errno));
return 0;
}
/* set timer */
if (timeout)
{
struct sigaction alrm;
alrm.sa_handler = sigalrm_handler;
sigemptyset(&alrm.sa_mask);
alrm.sa_flags = 0;
sigaction(SIGALRM, &alrm, 0);
alarm(timeout);
}
sz = recv(fd, buf, sizeof(buf), 0);
alarm(0);
if (sz < 0)
{
fprintf(stderr, "%s: error receiving response (%s)\n", me,
errno == EINTR ? "timed out" : strerror(errno));
return 0;
}
if ((type = unpack_control(&res, buf, sz)) > 0 && type & NSCTL_RESPONSE)
{
if (debug)
{
fprintf(stderr, "Received ");
dump_control(&res, stderr);
}
return &res;
}
err = "unknown error";
switch (type)
{
case NSCTL_ERR_SHORT: err = "short packet"; break;
case NSCTL_ERR_LONG: err = "extra data"; break;
case NSCTL_ERR_MAGIC: err = "bad magic"; break;
case NSCTL_ERR_TYPE: err = "invalid type"; break;
}
fprintf(stderr, "%s: %s\n", me, err);
return 0;
}