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/*
* (C) 2009 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* 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.
*/
#include <stdlib.h>
#include <unistd.h>
#include <net/if.h>
#include <string.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include "channel.h"
#include "network.h"
static struct channel_ops *ops[CHANNEL_MAX];
extern struct channel_ops channel_mcast;
extern struct channel_ops channel_udp;
void channel_init(void)
{
ops[CHANNEL_MCAST] = &channel_mcast;
ops[CHANNEL_UDP] = &channel_udp;
}
#define HEADERSIZ 28 /* IP header (20 bytes) + UDP header 8 (bytes) */
struct channel_buffer {
char *data;
int size;
int len;
};
static struct channel_buffer *
channel_buffer_open(int mtu)
{
struct channel_buffer *b;
b = calloc(sizeof(struct channel_buffer), 1);
if (b == NULL)
return NULL;
b->size = mtu - HEADERSIZ;
b->data = malloc(b->size);
if (b->data == NULL) {
free(b);
return NULL;
}
return b;
}
static void
channel_buffer_close(struct channel_buffer *b)
{
free(b->data);
free(b);
}
struct channel *
channel_open(struct channel_conf *conf)
{
struct channel *c;
struct ifreq ifr;
int fd;
if (conf->channel_type >= CHANNEL_MAX)
return NULL;
if (!conf->channel_ifname[0])
return NULL;
if (conf->channel_flags >= CHANNEL_F_MAX)
return NULL;
c = calloc(sizeof(struct channel), 1);
if (c == NULL)
return NULL;
c->channel_type = conf->channel_type;
fd = socket(AF_INET, SOCK_DGRAM, 0);
if (fd == -1) {
free(c);
return NULL;
}
strncpy(ifr.ifr_name, conf->channel_ifname, sizeof(ifr.ifr_name));
if (ioctl(fd, SIOCGIFMTU, &ifr) == -1) {
free(c);
return NULL;
}
close(fd);
c->channel_ifmtu = ifr.ifr_mtu;
c->channel_ifindex = if_nametoindex(conf->channel_ifname);
if (c->channel_ifindex == 0) {
free(c);
return NULL;
}
c->ops = ops[conf->channel_type];
if (conf->channel_flags & CHANNEL_F_BUFFERED) {
c->buffer = channel_buffer_open(c->channel_ifmtu);
if (c->buffer == NULL) {
free(c);
return NULL;
}
}
c->channel_flags = conf->channel_flags;
c->data = c->ops->open(&conf->u);
if (c->data == NULL) {
channel_buffer_close(c->buffer);
free(c);
return NULL;
}
return c;
}
void
channel_close(struct channel *c)
{
c->ops->close(c->data);
if (c->channel_flags & CHANNEL_F_BUFFERED)
channel_buffer_close(c->buffer);
free(c);
}
int channel_send(struct channel *c, const struct nethdr *net)
{
int ret = 0, len = ntohs(net->len);
if (!(c->channel_flags & CHANNEL_F_BUFFERED)) {
c->ops->send(c->data, net, len);
return 1;
}
retry:
if (c->buffer->len + len < c->buffer->size) {
memcpy(c->buffer->data + c->buffer->len, net, len);
c->buffer->len += len;
} else {
c->ops->send(c->data, c->buffer->data, c->buffer->len);
ret = 1;
c->buffer->len = 0;
goto retry;
}
return ret;
}
int channel_send_flush(struct channel *c)
{
if (!(c->channel_flags & CHANNEL_F_BUFFERED) || c->buffer->len == 0)
return 0;
c->ops->send(c->data, c->buffer->data, c->buffer->len);
c->buffer->len = 0;
return 1;
}
int channel_recv(struct channel *c, char *buf, int size)
{
return c->ops->recv(c->data, buf, size);
}
int channel_get_fd(struct channel *c)
{
return c->ops->get_fd(c->data);
}
void channel_stats(struct channel *c, int fd)
{
return c->ops->stats(c, fd);
}
void channel_stats_extended(struct channel *c, int active,
struct nlif_handle *h, int fd)
{
return c->ops->stats_extended(c, active, h, fd);
}
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