diff options
Diffstat (limited to 'net/ipv6/ip6_output.c')
| -rw-r--r-- | net/ipv6/ip6_output.c | 183 |
1 files changed, 107 insertions, 76 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 2567b22a888a..812a98b79ec6 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); @@ -792,91 +888,26 @@ slow_path_clean: } 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. */ err = output(net, sk, frag); |