[deliverable/linux.git] / net / ipv6 / output_core.c

/*
 * IPv6 library code, needed by static components when full IPv6 support is
 * not configured or static.  These functions are needed by GSO/GRO implementation.
 */
#include <linux/export.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/addrconf.h>
#include <net/secure_seq.h>

/* This function exists only for tap drivers that must support broken
 * clients requesting UFO without specifying an IPv6 fragment ID.
 *
 * This is similar to ipv6_select_ident() but we use an independent hash
 * seed to limit information leakage.
 *
 * The network header must be set before calling this.
 */
void ipv6_proxy_select_ident(struct sk_buff *skb)
{
	static u32 ip6_proxy_idents_hashrnd __read_mostly;
	struct in6_addr buf[2];
	struct in6_addr *addrs;
	u32 hash, id;

	addrs = skb_header_pointer(skb,
				   skb_network_offset(skb) +
				   offsetof(struct ipv6hdr, saddr),
				   sizeof(buf), buf);
	if (!addrs)
		return;

	net_get_random_once(&ip6_proxy_idents_hashrnd,
			    sizeof(ip6_proxy_idents_hashrnd));

	hash = __ipv6_addr_jhash(&addrs[1], ip6_proxy_idents_hashrnd);
	hash = __ipv6_addr_jhash(&addrs[0], hash);

	id = ip_idents_reserve(hash, 1);
	skb_shinfo(skb)->ip6_frag_id = htonl(id);
}
EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident);

int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
{
	u16 offset = sizeof(struct ipv6hdr);
	struct ipv6_opt_hdr *exthdr =
				(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
	unsigned int packet_len = skb_tail_pointer(skb) -
		skb_network_header(skb);
	int found_rhdr = 0;
	*nexthdr = &ipv6_hdr(skb)->nexthdr;

	while (offset + 1 <= packet_len) {

		switch (**nexthdr) {

		case NEXTHDR_HOP:
			break;
		case NEXTHDR_ROUTING:
			found_rhdr = 1;
			break;
		case NEXTHDR_DEST:
#if IS_ENABLED(CONFIG_IPV6_MIP6)
			if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
				break;
#endif
			if (found_rhdr)
				return offset;
			break;
		default:
			return offset;
		}

		offset += ipv6_optlen(exthdr);
		*nexthdr = &exthdr->nexthdr;
		exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
						 offset);
	}

	return offset;
}
EXPORT_SYMBOL(ip6_find_1stfragopt);

#if IS_ENABLED(CONFIG_IPV6)
int ip6_dst_hoplimit(struct dst_entry *dst)
{
	int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
	if (hoplimit == 0) {
		struct net_device *dev = dst->dev;
		struct inet6_dev *idev;

		rcu_read_lock();
		idev = __in6_dev_get(dev);
		if (idev)
			hoplimit = idev->cnf.hop_limit;
		else
			hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
		rcu_read_unlock();
	}
	return hoplimit;
}
EXPORT_SYMBOL(ip6_dst_hoplimit);
#endif

int __ip6_local_out(struct sk_buff *skb)
{
	int len;

	len = skb->len - sizeof(struct ipv6hdr);
	if (len > IPV6_MAXPLEN)
		len = 0;
	ipv6_hdr(skb)->payload_len = htons(len);
	IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);

	return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL,
		       skb_dst(skb)->dev, dst_output);
}
EXPORT_SYMBOL_GPL(__ip6_local_out);

int ip6_local_out(struct sk_buff *skb)
{
	int err;

	err = __ip6_local_out(skb);
	if (likely(err == 1))
		err = dst_output(skb);

	return err;
}
EXPORT_SYMBOL_GPL(ip6_local_out);
Commit	Line	Data
3c73a036 VY	1	/*
	2	* IPv6 library code, needed by static components when full IPv6 support is
	3	* not configured or static. These functions are needed by GSO/GRO implementation.
	4	*/
	5	#include <linux/export.h>
5188cd44	6	#include <net/ip.h>
3c73a036 VY	7	#include <net/ipv6.h>
3c73a036 VY	8	#include <net/ip6_fib.h>
3ce9b35f	9	#include <net/addrconf.h>
6dfac5c3	10	#include <net/secure_seq.h>
3c73a036	11
5188cd44 BH	12	/* This function exists only for tap drivers that must support broken
	13	* clients requesting UFO without specifying an IPv6 fragment ID.
	14	*
	15	* This is similar to ipv6_select_ident() but we use an independent hash
	16	* seed to limit information leakage.
	17	*
	18	* The network header must be set before calling this.
	19	*/
	20	void ipv6_proxy_select_ident(struct sk_buff *skb)
	21	{
	22	static u32 ip6_proxy_idents_hashrnd __read_mostly;
	23	struct in6_addr buf[2];
	24	struct in6_addr *addrs;
	25	u32 hash, id;
	26
	27	addrs = skb_header_pointer(skb,
	28	skb_network_offset(skb) +
	29	offsetof(struct ipv6hdr, saddr),
	30	sizeof(buf), buf);
	31	if (!addrs)
	32	return;
	33
	34	net_get_random_once(&ip6_proxy_idents_hashrnd,
	35	sizeof(ip6_proxy_idents_hashrnd));
	36
	37	hash = __ipv6_addr_jhash(&addrs[1], ip6_proxy_idents_hashrnd);
	38	hash = __ipv6_addr_jhash(&addrs[0], hash);
	39
	40	id = ip_idents_reserve(hash, 1);
	41	skb_shinfo(skb)->ip6_frag_id = htonl(id);
	42	}
	43	EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident);
	44
3c73a036 VY	45	int ip6_find_1stfragopt(struct sk_buff skb, u8 *nexthdr)
	46	{
	47	u16 offset = sizeof(struct ipv6hdr);
	48	struct ipv6_opt_hdr *exthdr =
	49	(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
29a3cad5 SH	50	unsigned int packet_len = skb_tail_pointer(skb) -
29a3cad5 SH	51	skb_network_header(skb);
3c73a036 VY	52	int found_rhdr = 0;
	53	*nexthdr = &ipv6_hdr(skb)->nexthdr;
	54
	55	while (offset + 1 <= packet_len) {
	56
	57	switch (**nexthdr) {
	58
	59	case NEXTHDR_HOP:
	60	break;
	61	case NEXTHDR_ROUTING:
	62	found_rhdr = 1;
	63	break;
	64	case NEXTHDR_DEST:
	65	#if IS_ENABLED(CONFIG_IPV6_MIP6)
	66	if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0)
	67	break;
	68	#endif
	69	if (found_rhdr)
	70	return offset;
	71	break;
67ba4152	72	default:
3c73a036 VY	73	return offset;
	74	}
	75
	76	offset += ipv6_optlen(exthdr);
	77	*nexthdr = &exthdr->nexthdr;
	78	exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
	79	offset);
	80	}
	81
	82	return offset;
	83	}
	84	EXPORT_SYMBOL(ip6_find_1stfragopt);
3ce9b35f CW	85
	86	#if IS_ENABLED(CONFIG_IPV6)
	87	int ip6_dst_hoplimit(struct dst_entry *dst)
	88	{
	89	int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT);
	90	if (hoplimit == 0) {
	91	struct net_device *dev = dst->dev;
	92	struct inet6_dev *idev;
	93
	94	rcu_read_lock();
	95	idev = __in6_dev_get(dev);
	96	if (idev)
	97	hoplimit = idev->cnf.hop_limit;
	98	else
	99	hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit;
	100	rcu_read_unlock();
	101	}
	102	return hoplimit;
	103	}
	104	EXPORT_SYMBOL(ip6_dst_hoplimit);
	105	#endif
788787b5 CW	106
	107	int __ip6_local_out(struct sk_buff *skb)
	108	{
	109	int len;
	110
	111	len = skb->len - sizeof(struct ipv6hdr);
	112	if (len > IPV6_MAXPLEN)
	113	len = 0;
	114	ipv6_hdr(skb)->payload_len = htons(len);
f6c20c59	115	IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
788787b5 CW	116
	117	return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL,
	118	skb_dst(skb)->dev, dst_output);
	119	}
	120	EXPORT_SYMBOL_GPL(__ip6_local_out);
	121
	122	int ip6_local_out(struct sk_buff *skb)
	123	{
	124	int err;
	125
	126	err = __ip6_local_out(skb);
	127	if (likely(err == 1))
	128	err = dst_output(skb);
	129
	130	return err;
	131	}
	132	EXPORT_SYMBOL_GPL(ip6_local_out);