igmp.c

linux 内核源代码

	struct ip_sf_socklist *psl;

	if (!MULTICAST(addr))
		return -EINVAL;

	rtnl_lock();

	imr.imr_multiaddr.s_addr = msf->imsf_multiaddr;
	imr.imr_address.s_addr = msf->imsf_interface;
	imr.imr_ifindex = 0;
	in_dev = ip_mc_find_dev(&imr);

	if (!in_dev) {
		err = -ENODEV;
		goto done;
	}
	err = -EADDRNOTAVAIL;

	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
		if (pmc->multi.imr_multiaddr.s_addr == msf->imsf_multiaddr &&
		    pmc->multi.imr_ifindex == imr.imr_ifindex)
			break;
	}
	if (!pmc)		/* must have a prior join */
		goto done;
	msf->imsf_fmode = pmc->sfmode;
	psl = pmc->sflist;
	rtnl_unlock();
	if (!psl) {
		len = 0;
		count = 0;
	} else {
		count = psl->sl_count;
	}
	copycount = count < msf->imsf_numsrc ? count : msf->imsf_numsrc;
	len = copycount * sizeof(psl->sl_addr[0]);
	msf->imsf_numsrc = count;
	if (put_user(IP_MSFILTER_SIZE(copycount), optlen) ||
	    copy_to_user(optval, msf, IP_MSFILTER_SIZE(0))) {
		return -EFAULT;
	}
	if (len &&
	    copy_to_user(&optval->imsf_slist[0], psl->sl_addr, len))
		return -EFAULT;
	return 0;
done:
	rtnl_unlock();
	return err;
}

int ip_mc_gsfget(struct sock *sk, struct group_filter *gsf,
	struct group_filter __user *optval, int __user *optlen)
{
	int err, i, count, copycount;
	struct sockaddr_in *psin;
	__be32 addr;
	struct ip_mc_socklist *pmc;
	struct inet_sock *inet = inet_sk(sk);
	struct ip_sf_socklist *psl;

	psin = (struct sockaddr_in *)&gsf->gf_group;
	if (psin->sin_family != AF_INET)
		return -EINVAL;
	addr = psin->sin_addr.s_addr;
	if (!MULTICAST(addr))
		return -EINVAL;

	rtnl_lock();

	err = -EADDRNOTAVAIL;

	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
		if (pmc->multi.imr_multiaddr.s_addr == addr &&
		    pmc->multi.imr_ifindex == gsf->gf_interface)
			break;
	}
	if (!pmc)		/* must have a prior join */
		goto done;
	gsf->gf_fmode = pmc->sfmode;
	psl = pmc->sflist;
	rtnl_unlock();
	count = psl ? psl->sl_count : 0;
	copycount = count < gsf->gf_numsrc ? count : gsf->gf_numsrc;
	gsf->gf_numsrc = count;
	if (put_user(GROUP_FILTER_SIZE(copycount), optlen) ||
	    copy_to_user(optval, gsf, GROUP_FILTER_SIZE(0))) {
		return -EFAULT;
	}
	for (i=0; i<copycount; i++) {
		struct sockaddr_storage ss;

		psin = (struct sockaddr_in *)&ss;
		memset(&ss, 0, sizeof(ss));
		psin->sin_family = AF_INET;
		psin->sin_addr.s_addr = psl->sl_addr[i];
		if (copy_to_user(&optval->gf_slist[i], &ss, sizeof(ss)))
			return -EFAULT;
	}
	return 0;
done:
	rtnl_unlock();
	return err;
}

/*
 * check if a multicast source filter allows delivery for a given <src,dst,intf>
 */
int ip_mc_sf_allow(struct sock *sk, __be32 loc_addr, __be32 rmt_addr, int dif)
{
	struct inet_sock *inet = inet_sk(sk);
	struct ip_mc_socklist *pmc;
	struct ip_sf_socklist *psl;
	int i;

	if (!MULTICAST(loc_addr))
		return 1;

	for (pmc=inet->mc_list; pmc; pmc=pmc->next) {
		if (pmc->multi.imr_multiaddr.s_addr == loc_addr &&
		    pmc->multi.imr_ifindex == dif)
			break;
	}
	if (!pmc)
		return 1;
	psl = pmc->sflist;
	if (!psl)
		return pmc->sfmode == MCAST_EXCLUDE;

	for (i=0; i<psl->sl_count; i++) {
		if (psl->sl_addr[i] == rmt_addr)
			break;
	}
	if (pmc->sfmode == MCAST_INCLUDE && i >= psl->sl_count)
		return 0;
	if (pmc->sfmode == MCAST_EXCLUDE && i < psl->sl_count)
		return 0;
	return 1;
}

/*
 *	A socket is closing.
 */

void ip_mc_drop_socket(struct sock *sk)
{
	struct inet_sock *inet = inet_sk(sk);
	struct ip_mc_socklist *iml;

	if (inet->mc_list == NULL)
		return;

	rtnl_lock();
	while ((iml = inet->mc_list) != NULL) {
		struct in_device *in_dev;
		inet->mc_list = iml->next;

		in_dev = inetdev_by_index(iml->multi.imr_ifindex);
		(void) ip_mc_leave_src(sk, iml, in_dev);
		if (in_dev != NULL) {
			ip_mc_dec_group(in_dev, iml->multi.imr_multiaddr.s_addr);
			in_dev_put(in_dev);
		}
		sock_kfree_s(sk, iml, sizeof(*iml));
	}
	rtnl_unlock();
}

int ip_check_mc(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
{
	struct ip_mc_list *im;
	struct ip_sf_list *psf;
	int rv = 0;

	read_lock(&in_dev->mc_list_lock);
	for (im=in_dev->mc_list; im; im=im->next) {
		if (im->multiaddr == mc_addr)
			break;
	}
	if (im && proto == IPPROTO_IGMP) {
		rv = 1;
	} else if (im) {
		if (src_addr) {
			for (psf=im->sources; psf; psf=psf->sf_next) {
				if (psf->sf_inaddr == src_addr)
					break;
			}
			if (psf)
				rv = psf->sf_count[MCAST_INCLUDE] ||
					psf->sf_count[MCAST_EXCLUDE] !=
					im->sfcount[MCAST_EXCLUDE];
			else
				rv = im->sfcount[MCAST_EXCLUDE] != 0;
		} else
			rv = 1; /* unspecified source; tentatively allow */
	}
	read_unlock(&in_dev->mc_list_lock);
	return rv;
}

#if defined(CONFIG_PROC_FS)
struct igmp_mc_iter_state {
	struct net_device *dev;
	struct in_device *in_dev;
};

#define	igmp_mc_seq_private(seq)	((struct igmp_mc_iter_state *)(seq)->private)

static inline struct ip_mc_list *igmp_mc_get_first(struct seq_file *seq)
{
	struct ip_mc_list *im = NULL;
	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);

	state->in_dev = NULL;
	for_each_netdev(&init_net, state->dev) {
		struct in_device *in_dev;
		in_dev = in_dev_get(state->dev);
		if (!in_dev)
			continue;
		read_lock(&in_dev->mc_list_lock);
		im = in_dev->mc_list;
		if (im) {
			state->in_dev = in_dev;
			break;
		}
		read_unlock(&in_dev->mc_list_lock);
		in_dev_put(in_dev);
	}
	return im;
}

static struct ip_mc_list *igmp_mc_get_next(struct seq_file *seq, struct ip_mc_list *im)
{
	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
	im = im->next;
	while (!im) {
		if (likely(state->in_dev != NULL)) {
			read_unlock(&state->in_dev->mc_list_lock);
			in_dev_put(state->in_dev);
		}
		state->dev = next_net_device(state->dev);
		if (!state->dev) {
			state->in_dev = NULL;
			break;
		}
		state->in_dev = in_dev_get(state->dev);
		if (!state->in_dev)
			continue;
		read_lock(&state->in_dev->mc_list_lock);
		im = state->in_dev->mc_list;
	}
	return im;
}

static struct ip_mc_list *igmp_mc_get_idx(struct seq_file *seq, loff_t pos)
{
	struct ip_mc_list *im = igmp_mc_get_first(seq);
	if (im)
		while (pos && (im = igmp_mc_get_next(seq, im)) != NULL)
			--pos;
	return pos ? NULL : im;
}

static void *igmp_mc_seq_start(struct seq_file *seq, loff_t *pos)
{
	read_lock(&dev_base_lock);
	return *pos ? igmp_mc_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
}

static void *igmp_mc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	struct ip_mc_list *im;
	if (v == SEQ_START_TOKEN)
		im = igmp_mc_get_first(seq);
	else
		im = igmp_mc_get_next(seq, v);
	++*pos;
	return im;
}

static void igmp_mc_seq_stop(struct seq_file *seq, void *v)
{
	struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
	if (likely(state->in_dev != NULL)) {
		read_unlock(&state->in_dev->mc_list_lock);
		in_dev_put(state->in_dev);
		state->in_dev = NULL;
	}
	state->dev = NULL;
	read_unlock(&dev_base_lock);
}

static int igmp_mc_seq_show(struct seq_file *seq, void *v)
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq,
			 "Idx\tDevice    : Count Querier\tGroup    Users Timer\tReporter\n");
	else {
		struct ip_mc_list *im = (struct ip_mc_list *)v;
		struct igmp_mc_iter_state *state = igmp_mc_seq_private(seq);
		char   *querier;
#ifdef CONFIG_IP_MULTICAST
		querier = IGMP_V1_SEEN(state->in_dev) ? "V1" :
			  IGMP_V2_SEEN(state->in_dev) ? "V2" :
			  "V3";
#else
		querier = "NONE";
#endif

		if (state->in_dev->mc_list == im) {
			seq_printf(seq, "%d\t%-10s: %5d %7s\n",
				   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
		}

		seq_printf(seq,
			   "\t\t\t\t%08X %5d %d:%08lX\t\t%d\n",
			   im->multiaddr, im->users,
			   im->tm_running, im->tm_running ?
			   jiffies_to_clock_t(im->timer.expires-jiffies) : 0,
			   im->reporter);
	}
	return 0;
}

static const struct seq_operations igmp_mc_seq_ops = {
	.start	=	igmp_mc_seq_start,
	.next	=	igmp_mc_seq_next,
	.stop	=	igmp_mc_seq_stop,
	.show	=	igmp_mc_seq_show,
};

static int igmp_mc_seq_open(struct inode *inode, struct file *file)
{
	return seq_open_private(file, &igmp_mc_seq_ops,
			sizeof(struct igmp_mc_iter_state));
}

static const struct file_operations igmp_mc_seq_fops = {
	.owner		=	THIS_MODULE,
	.open		=	igmp_mc_seq_open,
	.read		=	seq_read,
	.llseek		=	seq_lseek,
	.release	=	seq_release_private,
};

struct igmp_mcf_iter_state {
	struct net_device *dev;
	struct in_device *idev;
	struct ip_mc_list *im;
};

#define igmp_mcf_seq_private(seq)	((struct igmp_mcf_iter_state *)(seq)->private)

static inline struct ip_sf_list *igmp_mcf_get_first(struct seq_file *seq)
{
	struct ip_sf_list *psf = NULL;
	struct ip_mc_list *im = NULL;
	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);

	state->idev = NULL;
	state->im = NULL;
	for_each_netdev(&init_net, state->dev) {
		struct in_device *idev;
		idev = in_dev_get(state->dev);
		if (unlikely(idev == NULL))
			continue;
		read_lock(&idev->mc_list_lock);
		im = idev->mc_list;
		if (likely(im != NULL)) {
			spin_lock_bh(&im->lock);
			psf = im->sources;
			if (likely(psf != NULL)) {
				state->im = im;
				state->idev = idev;
				break;
			}
			spin_unlock_bh(&im->lock);
		}
		read_unlock(&idev->mc_list_lock);
		in_dev_put(idev);
	}
	return psf;
}

static struct ip_sf_list *igmp_mcf_get_next(struct seq_file *seq, struct ip_sf_list *psf)
{
	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);

	psf = psf->sf_next;
	while (!psf) {
		spin_unlock_bh(&state->im->lock);
		state->im = state->im->next;
		while (!state->im) {
			if (likely(state->idev != NULL)) {
				read_unlock(&state->idev->mc_list_lock);
				in_dev_put(state->idev);
			}
			state->dev = next_net_device(state->dev);
			if (!state->dev) {
				state->idev = NULL;
				goto out;
			}
			state->idev = in_dev_get(state->dev);
			if (!state->idev)
				continue;
			read_lock(&state->idev->mc_list_lock);
			state->im = state->idev->mc_list;
		}
		if (!state->im)
			break;
		spin_lock_bh(&state->im->lock);
		psf = state->im->sources;
	}
out:
	return psf;
}

static struct ip_sf_list *igmp_mcf_get_idx(struct seq_file *seq, loff_t pos)
{
	struct ip_sf_list *psf = igmp_mcf_get_first(seq);
	if (psf)
		while (pos && (psf = igmp_mcf_get_next(seq, psf)) != NULL)
			--pos;
	return pos ? NULL : psf;
}

static void *igmp_mcf_seq_start(struct seq_file *seq, loff_t *pos)
{
	read_lock(&dev_base_lock);
	return *pos ? igmp_mcf_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
}

static void *igmp_mcf_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	struct ip_sf_list *psf;
	if (v == SEQ_START_TOKEN)
		psf = igmp_mcf_get_first(seq);
	else
		psf = igmp_mcf_get_next(seq, v);
	++*pos;
	return psf;
}

static void igmp_mcf_seq_stop(struct seq_file *seq, void *v)
{
	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);
	if (likely(state->im != NULL)) {
		spin_unlock_bh(&state->im->lock);
		state->im = NULL;
	}
	if (likely(state->idev != NULL)) {
		read_unlock(&state->idev->mc_list_lock);
		in_dev_put(state->idev);
		state->idev = NULL;
	}
	state->dev = NULL;
	read_unlock(&dev_base_lock);
}

static int igmp_mcf_seq_show(struct seq_file *seq, void *v)
{
	struct ip_sf_list *psf = (struct ip_sf_list *)v;
	struct igmp_mcf_iter_state *state = igmp_mcf_seq_private(seq);

	if (v == SEQ_START_TOKEN) {
		seq_printf(seq,
			   "%3s %6s "
			   "%10s %10s %6s %6s\n", "Idx",
			   "Device", "MCA",
			   "SRC", "INC", "EXC");
	} else {
		seq_printf(seq,
			   "%3d %6.6s 0x%08x "
			   "0x%08x %6lu %6lu\n",
			   state->dev->ifindex, state->dev->name,
			   ntohl(state->im->multiaddr),
			   ntohl(psf->sf_inaddr),
			   psf->sf_count[MCAST_INCLUDE],
			   psf->sf_count[MCAST_EXCLUDE]);
	}
	return 0;
}

static const struct seq_operations igmp_mcf_seq_ops = {
	.start	=	igmp_mcf_seq_start,
	.next	=	igmp_mcf_seq_next,
	.stop	=	igmp_mcf_seq_stop,
	.show	=	igmp_mcf_seq_show,
};

static int igmp_mcf_seq_open(struct inode *inode, struct file *file)
{
	return seq_open_private(file, &igmp_mcf_seq_ops,
			sizeof(struct igmp_mcf_iter_state));
}

static const struct file_operations igmp_mcf_seq_fops = {
	.owner		=	THIS_MODULE,
	.open		=	igmp_mcf_seq_open,
	.read		=	seq_read,
	.llseek		=	seq_lseek,
	.release	=	seq_release_private,
};

int __init igmp_mc_proc_init(void)
{
	proc_net_fops_create(&init_net, "igmp", S_IRUGO, &igmp_mc_seq_fops);
	proc_net_fops_create(&init_net, "mcfilter", S_IRUGO, &igmp_mcf_seq_fops);
	return 0;
}
#endif

EXPORT_SYMBOL(ip_mc_dec_group);
EXPORT_SYMBOL(ip_mc_inc_group);
EXPORT_SYMBOL(ip_mc_join_group);
EXPORT_SYMBOL(ip_mc_rejoin_group);