diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index acefbc718abe2daf3c3a49b48d4ff13c42cfb20c..21bb830e9679b19fafb245b4a7f6a1f874811bd9 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -179,6 +179,25 @@ static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter)
return skb;
}
+struct ip6_frag_state {
+ u8 *prevhdr;
+ unsigned int hlen;
+ unsigned int mtu;
+ unsigned int left;
+ int offset;
+ int ptr;
+ int hroom;
+ int troom;
+ __be32 frag_id;
+ u8 nexthdr;
+};
+
+void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
+ unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
+ u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state);
+struct sk_buff *ip6_frag_next(struct sk_buff *skb,
+ struct ip6_frag_state *state);
+
#define IP6_REPLY_MARK(net, mark) \
((net)->ipv6.sysctl.fwmark_reflect ? (mark) : 0)
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 2567b22a888aebfc08e7db678aca53697422596e..812a98b79ec693302df8d8832f90479f88668691 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -659,6 +659,103 @@ void ip6_fraglist_prepare(struct sk_buff *skb,
}
EXPORT_SYMBOL(ip6_fraglist_prepare);
+void ip6_frag_init(struct sk_buff *skb, unsigned int hlen, unsigned int mtu,
+ unsigned short needed_tailroom, int hdr_room, u8 *prevhdr,
+ u8 nexthdr, __be32 frag_id, struct ip6_frag_state *state)
+{
+ state->prevhdr = prevhdr;
+ state->nexthdr = nexthdr;
+ state->frag_id = frag_id;
+
+ state->hlen = hlen;
+ state->mtu = mtu;
+
+ state->left = skb->len - hlen; /* Space per frame */
+ state->ptr = hlen; /* Where to start from */
+
+ state->hroom = hdr_room;
+ state->troom = needed_tailroom;
+
+ state->offset = 0;
+}
+EXPORT_SYMBOL(ip6_frag_init);
+
+struct sk_buff *ip6_frag_next(struct sk_buff *skb, struct ip6_frag_state *state)
+{
+ u8 *prevhdr = state->prevhdr, *fragnexthdr_offset;
+ struct sk_buff *frag;
+ struct frag_hdr *fh;
+ unsigned int len;
+
+ len = state->left;
+ /* IF: it doesn't fit, use 'mtu' - the data space left */
+ if (len > state->mtu)
+ len = state->mtu;
+ /* IF: we are not sending up to and including the packet end
+ then align the next start on an eight byte boundary */
+ if (len < state->left)
+ len &= ~7;
+
+ /* Allocate buffer */
+ frag = alloc_skb(len + state->hlen + sizeof(struct frag_hdr) +
+ state->hroom + state->troom, GFP_ATOMIC);
+ if (!frag)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * Set up data on packet
+ */
+
+ ip6_copy_metadata(frag, skb);
+ skb_reserve(frag, state->hroom);
+ skb_put(frag, len + state->hlen + sizeof(struct frag_hdr));
+ skb_reset_network_header(frag);
+ fh = (struct frag_hdr *)(skb_network_header(frag) + state->hlen);
+ frag->transport_header = (frag->network_header + state->hlen +
+ sizeof(struct frag_hdr));
+
+ /*
+ * Charge the memory for the fragment to any owner
+ * it might possess
+ */
+ if (skb->sk)
+ skb_set_owner_w(frag, skb->sk);
+
+ /*
+ * Copy the packet header into the new buffer.
+ */
+ skb_copy_from_linear_data(skb, skb_network_header(frag), state->hlen);
+
+ fragnexthdr_offset = skb_network_header(frag);
+ fragnexthdr_offset += prevhdr - skb_network_header(skb);
+ *fragnexthdr_offset = NEXTHDR_FRAGMENT;
+
+ /*
+ * Build fragment header.
+ */
+ fh->nexthdr = state->nexthdr;
+ fh->reserved = 0;
+ fh->identification = state->frag_id;
+
+ /*
+ * Copy a block of the IP datagram.
+ */
+ BUG_ON(skb_copy_bits(skb, state->ptr, skb_transport_header(frag),
+ len));
+ state->left -= len;
+
+ fh->frag_off = htons(state->offset);
+ if (state->left > 0)
+ fh->frag_off |= htons(IP6_MF);
+ ipv6_hdr(frag)->payload_len = htons(frag->len - sizeof(struct ipv6hdr));
+
+ state->ptr += len;
+ state->offset += len;
+
+ return frag;
+}
+EXPORT_SYMBOL(ip6_frag_next);
+
int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
int (*output)(struct net *, struct sock *, struct sk_buff *))
{
@@ -666,11 +763,10 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
inet6_sk(skb->sk) : NULL;
- struct frag_hdr *fh;
- unsigned int mtu, hlen, left, len, nexthdr_offset;
- int hroom, troom;
+ struct ip6_frag_state state;
+ unsigned int mtu, hlen, nexthdr_offset;
+ int hroom, err = 0;
__be32 frag_id;
- int ptr, offset = 0, err = 0;
u8 *prevhdr, nexthdr = 0;
err = ip6_find_1stfragopt(skb, &prevhdr);
@@ -792,90 +888,25 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
}
slow_path:
- left = skb->len - hlen; /* Space per frame */
- ptr = hlen; /* Where to start from */
-
/*
* Fragment the datagram.
*/
- troom = rt->dst.dev->needed_tailroom;
+ ip6_frag_init(skb, hlen, mtu, rt->dst.dev->needed_tailroom,
+ LL_RESERVED_SPACE(rt->dst.dev), prevhdr, nexthdr, frag_id,
+ &state);
/*
* Keep copying data until we run out.
*/
- while (left > 0) {
- u8 *fragnexthdr_offset;
-
- len = left;
- /* IF: it doesn't fit, use 'mtu' - the data space left */
- if (len > mtu)
- len = mtu;
- /* IF: we are not sending up to and including the packet end
- then align the next start on an eight byte boundary */
- if (len < left) {
- len &= ~7;
- }
- /* Allocate buffer */
- frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
- hroom + troom, GFP_ATOMIC);
- if (!frag) {
- err = -ENOMEM;
+ while (state.left > 0) {
+ frag = ip6_frag_next(skb, &state);
+ if (IS_ERR(frag)) {
+ err = PTR_ERR(frag);
goto fail;
}
- /*
- * Set up data on packet
- */
-
- ip6_copy_metadata(frag, skb);
- skb_reserve(frag, hroom);
- skb_put(frag, len + hlen + sizeof(struct frag_hdr));
- skb_reset_network_header(frag);
- fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
- frag->transport_header = (frag->network_header + hlen +
- sizeof(struct frag_hdr));
-
- /*
- * Charge the memory for the fragment to any owner
- * it might possess
- */
- if (skb->sk)
- skb_set_owner_w(frag, skb->sk);
-
- /*
- * Copy the packet header into the new buffer.
- */
- skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
-
- fragnexthdr_offset = skb_network_header(frag);
- fragnexthdr_offset += prevhdr - skb_network_header(skb);
- *fragnexthdr_offset = NEXTHDR_FRAGMENT;
-
- /*
- * Build fragment header.
- */
- fh->nexthdr = nexthdr;
- fh->reserved = 0;
- fh->identification = frag_id;
-
- /*
- * Copy a block of the IP datagram.
- */
- BUG_ON(skb_copy_bits(skb, ptr, skb_transport_header(frag),
- len));
- left -= len;
-
- fh->frag_off = htons(offset);
- if (left > 0)
- fh->frag_off |= htons(IP6_MF);
- ipv6_hdr(frag)->payload_len = htons(frag->len -
- sizeof(struct ipv6hdr));
-
- ptr += len;
- offset += len;
-
/*
* Put this fragment into the sending queue.
*/