diff --git a/include/net/ipv6.h b/include/net/ipv6.h index daf80863d3a5..acefbc718abe 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -154,6 +154,31 @@ struct frag_hdr { #define IP6_MF 0x0001 #define IP6_OFFSET 0xFFF8 +struct ip6_fraglist_iter { + struct ipv6hdr *tmp_hdr; + struct sk_buff *frag_list; + struct sk_buff *frag; + int offset; + unsigned int hlen; + __be32 frag_id; + u8 nexthdr; +}; + +int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr, + u8 nexthdr, __be32 frag_id, + struct ip6_fraglist_iter *iter); +void ip6_fraglist_prepare(struct sk_buff *skb, struct ip6_fraglist_iter *iter); + +static inline struct sk_buff *ip6_fraglist_next(struct ip6_fraglist_iter *iter) +{ + struct sk_buff *skb = iter->frag; + + iter->frag = skb->next; + skb_mark_not_on_list(skb); + + return skb; +} + #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 adef2236abe2..2567b22a888a 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -592,6 +592,73 @@ static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) skb_copy_secmark(to, from); } +int ip6_fraglist_init(struct sk_buff *skb, unsigned int hlen, u8 *prevhdr, + u8 nexthdr, __be32 frag_id, + struct ip6_fraglist_iter *iter) +{ + unsigned int first_len; + struct frag_hdr *fh; + + /* BUILD HEADER */ + *prevhdr = NEXTHDR_FRAGMENT; + iter->tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC); + if (!iter->tmp_hdr) + return -ENOMEM; + + iter->frag_list = skb_shinfo(skb)->frag_list; + iter->frag = iter->frag_list; + skb_frag_list_init(skb); + + iter->offset = 0; + iter->hlen = hlen; + iter->frag_id = frag_id; + iter->nexthdr = nexthdr; + + __skb_pull(skb, hlen); + fh = __skb_push(skb, sizeof(struct frag_hdr)); + __skb_push(skb, hlen); + skb_reset_network_header(skb); + memcpy(skb_network_header(skb), iter->tmp_hdr, hlen); + + fh->nexthdr = nexthdr; + fh->reserved = 0; + fh->frag_off = htons(IP6_MF); + fh->identification = frag_id; + + first_len = skb_pagelen(skb); + skb->data_len = first_len - skb_headlen(skb); + skb->len = first_len; + ipv6_hdr(skb)->payload_len = htons(first_len - sizeof(struct ipv6hdr)); + + return 0; +} +EXPORT_SYMBOL(ip6_fraglist_init); + +void ip6_fraglist_prepare(struct sk_buff *skb, + struct ip6_fraglist_iter *iter) +{ + struct sk_buff *frag = iter->frag; + unsigned int hlen = iter->hlen; + struct frag_hdr *fh; + + frag->ip_summed = CHECKSUM_NONE; + skb_reset_transport_header(frag); + fh = __skb_push(frag, sizeof(struct frag_hdr)); + __skb_push(frag, hlen); + skb_reset_network_header(frag); + memcpy(skb_network_header(frag), iter->tmp_hdr, hlen); + iter->offset += skb->len - hlen - sizeof(struct frag_hdr); + fh->nexthdr = iter->nexthdr; + fh->reserved = 0; + fh->frag_off = htons(iter->offset); + if (frag->next) + fh->frag_off |= htons(IP6_MF); + fh->identification = iter->frag_id; + ipv6_hdr(frag)->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); + ip6_copy_metadata(frag, skb); +} +EXPORT_SYMBOL(ip6_fraglist_prepare); + int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, int (*output)(struct net *, struct sock *, struct sk_buff *)) { @@ -599,7 +666,6 @@ 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 ipv6hdr *tmp_hdr; struct frag_hdr *fh; unsigned int mtu, hlen, left, len, nexthdr_offset; int hroom, troom; @@ -651,6 +717,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, hroom = LL_RESERVED_SPACE(rt->dst.dev); if (skb_has_frag_list(skb)) { unsigned int first_len = skb_pagelen(skb); + struct ip6_fraglist_iter iter; struct sk_buff *frag2; if (first_len - hlen > mtu || @@ -678,74 +745,29 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, skb->truesize -= frag->truesize; } - err = 0; - offset = 0; - /* BUILD HEADER */ - - *prevhdr = NEXTHDR_FRAGMENT; - tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC); - if (!tmp_hdr) { - err = -ENOMEM; + err = ip6_fraglist_init(skb, hlen, prevhdr, nexthdr, frag_id, + &iter); + if (err < 0) goto fail; - } - frag = skb_shinfo(skb)->frag_list; - skb_frag_list_init(skb); - - __skb_pull(skb, hlen); - fh = __skb_push(skb, sizeof(struct frag_hdr)); - __skb_push(skb, hlen); - skb_reset_network_header(skb); - memcpy(skb_network_header(skb), tmp_hdr, hlen); - - fh->nexthdr = nexthdr; - fh->reserved = 0; - fh->frag_off = htons(IP6_MF); - fh->identification = frag_id; - - first_len = skb_pagelen(skb); - skb->data_len = first_len - skb_headlen(skb); - skb->len = first_len; - ipv6_hdr(skb)->payload_len = htons(first_len - - sizeof(struct ipv6hdr)); for (;;) { /* Prepare header of the next frame, * before previous one went down. */ - if (frag) { - frag->ip_summed = CHECKSUM_NONE; - skb_reset_transport_header(frag); - fh = __skb_push(frag, sizeof(struct frag_hdr)); - __skb_push(frag, hlen); - skb_reset_network_header(frag); - memcpy(skb_network_header(frag), tmp_hdr, - hlen); - offset += skb->len - hlen - sizeof(struct frag_hdr); - fh->nexthdr = nexthdr; - fh->reserved = 0; - fh->frag_off = htons(offset); - if (frag->next) - fh->frag_off |= htons(IP6_MF); - fh->identification = frag_id; - ipv6_hdr(frag)->payload_len = - htons(frag->len - - sizeof(struct ipv6hdr)); - ip6_copy_metadata(frag, skb); - } + if (iter.frag) + ip6_fraglist_prepare(skb, &iter); err = output(net, sk, skb); if (!err) IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), IPSTATS_MIB_FRAGCREATES); - if (err || !frag) + if (err || !iter.frag) break; - skb = frag; - frag = skb->next; - skb_mark_not_on_list(skb); + skb = ip6_fraglist_next(&iter); } - kfree(tmp_hdr); + kfree(iter.tmp_hdr); if (err == 0) { IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), @@ -753,7 +775,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb, return 0; } - kfree_skb_list(frag); + kfree_skb_list(iter.frag_list); IP6_INC_STATS(net, ip6_dst_idev(&rt->dst), IPSTATS_MIB_FRAGFAILS);