Function ng_ksocket_newhook

freebsd/netgraph/ng_ksocket.c:539–599

* Give our OK for a hook to be added. The hook name is of the * form " / / " where the three components may * be decimal numbers or else aliases from the above lists. * * Connecting a hook amounts to opening the socket. Disconnecting * the hook closes the socket and destroys the node as well. */

 * the hook closes the socket and destroys the node as well.
 */
static int
ng_ksocket_newhook(node_p node, hook_p hook, const char *name0)
{
	struct thread *td = curthread;	/* XXX broken */
	const priv_p priv = NG_NODE_PRIVATE(node);
	char *s1, *s2, name[NG_HOOKSIZ];
	int family, type, protocol, error;

	/* Check if we're already connected */
	if (priv->hook != NULL)
		return (EISCONN);

	if (priv->flags & KSF_CLONED) {
		if (priv->flags & KSF_EMBRYONIC) {
			/* Remove ourselves from our parent's embryo list */
			LIST_REMOVE(priv, siblings);
			priv->flags &= ~KSF_EMBRYONIC;
		}
	} else {
		/* Extract family, type, and protocol from hook name */
		snprintf(name, sizeof(name), "%s", name0);
		s1 = name;
		if ((s2 = strchr(s1, '/')) == NULL)
			return (EINVAL);
		*s2++ = '\0';
		family = ng_ksocket_parse(ng_ksocket_families, s1, 0);
		if (family == -1)
			return (EINVAL);
		s1 = s2;
		if ((s2 = strchr(s1, '/')) == NULL)
			return (EINVAL);
		*s2++ = '\0';
		type = ng_ksocket_parse(ng_ksocket_types, s1, 0);
		if (type == -1)
			return (EINVAL);
		s1 = s2;
		protocol = ng_ksocket_parse(ng_ksocket_protos, s1, family);
		if (protocol == -1)
			return (EINVAL);

		/* Create the socket */
		error = socreate(family, &priv->so, type, protocol,
		   td->td_ucred, td);
		if (error != 0)
			return (error);

		/* XXX call soreserve() ? */
	}

	/* OK */
	priv->hook = hook;

	/*
	 * In case of misconfigured routing a packet may reenter
	 * ksocket node recursively. Decouple stack to avoid possible
	 * panics about sleeping with locks held.
	 */
	NG_HOOK_FORCE_QUEUE(hook);