Initial import

1 files changed, 175 insertions, 0 deletions

diff --git a/net/ipv6/output_core.c b/net/ipv6/output_core.c
new file mode 100644
index 000000000..85892af57
--- /dev/null
+++ b/net/ipv6/output_core.c
@@ -0,0 +1,175 @@
+/*
+ * 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>
+
+static u32 __ipv6_select_ident(struct net *net, u32 hashrnd,
+			       struct in6_addr *dst, struct in6_addr *src)
+{
+	u32 hash, id;
+
+	hash = __ipv6_addr_jhash(dst, hashrnd);
+	hash = __ipv6_addr_jhash(src, hash);
+	hash ^= net_hash_mix(net);
+
+	/* Treat id of 0 as unset and if we get 0 back from ip_idents_reserve,
+	 * set the hight order instead thus minimizing possible future
+	 * collisions.
+	 */
+	id = ip_idents_reserve(hash, 1);
+	if (unlikely(!id))
+		id = 1 << 31;
+
+	return id;
+}
+
+/* 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 net *net, struct sk_buff *skb)
+{
+	static u32 ip6_proxy_idents_hashrnd __read_mostly;
+	struct in6_addr buf[2];
+	struct in6_addr *addrs;
+	u32 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));
+
+	id = __ipv6_select_ident(net, ip6_proxy_idents_hashrnd,
+				 &addrs[1], &addrs[0]);
+	skb_shinfo(skb)->ip6_frag_id = htonl(id);
+}
+EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident);
+
+void ipv6_select_ident(struct net *net, struct frag_hdr *fhdr,
+		       struct rt6_info *rt)
+{
+	static u32 ip6_idents_hashrnd __read_mostly;
+	u32 id;
+
+	net_get_random_once(&ip6_idents_hashrnd, sizeof(ip6_idents_hashrnd));
+
+	id = __ipv6_select_ident(net, ip6_idents_hashrnd, &rt->rt6i_dst.addr,
+				 &rt->rt6i_src.addr);
+	fhdr->identification = htonl(id);
+}
+EXPORT_SYMBOL(ipv6_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
+
+static int __ip6_local_out_sk(struct sock *sk, 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, sk, skb,
+		       NULL, skb_dst(skb)->dev, dst_output_sk);
+}
+
+int __ip6_local_out(struct sk_buff *skb)
+{
+	return __ip6_local_out_sk(skb->sk, skb);
+}
+EXPORT_SYMBOL_GPL(__ip6_local_out);
+
+int ip6_local_out_sk(struct sock *sk, struct sk_buff *skb)
+{
+	int err;
+
+	err = __ip6_local_out_sk(sk, skb);
+	if (likely(err == 1))
+		err = dst_output_sk(sk, skb);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(ip6_local_out_sk);
+
+int ip6_local_out(struct sk_buff *skb)
+{
+	return ip6_local_out_sk(skb->sk, skb);
+}
+EXPORT_SYMBOL_GPL(ip6_local_out);