__sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, u_int8_t protocol) { struct ipv6hdr *ip6h = ipv6_hdr(skb); __sum16 csum = 0; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) break; if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb->len - dataoff, protocol, csum_sub(skb->csum, skb_checksum(skb, 0, dataoff, 0)))) { skb->ip_summed = CHECKSUM_UNNECESSARY; break; } /* fall through */ case CHECKSUM_NONE: skb->csum = ~csum_unfold( csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb->len - dataoff, protocol, csum_sub(0, skb_checksum(skb, 0, dataoff, 0)))); csum = __skb_checksum_complete(skb); } return csum; }
/* remove VLAN header from packet and update csum accordingly. */ static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci) { struct vlan_hdr *vhdr; int err; err = make_writable(skb, VLAN_ETH_HLEN); if (unlikely(err)) return err; if (skb->ip_summed == CHECKSUM_COMPLETE) skb->csum = csum_sub(skb->csum, csum_partial(skb->data + (2 * ETH_ALEN), VLAN_HLEN, 0)); vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN); *current_tci = vhdr->h_vlan_TCI; memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN); __skb_pull(skb, VLAN_HLEN); vlan_set_encap_proto(skb, vhdr); skb->mac_header += VLAN_HLEN; /* Update mac_len for subsequent MPLS actions */ skb->mac_len -= VLAN_HLEN; return 0; }
static int pop_mpls(struct sk_buff *skb, const __be16 ethertype) { struct ethhdr *hdr; int err; err = make_writable(skb, skb->mac_len + MPLS_HLEN); if (unlikely(err)) return err; if (skb->ip_summed == CHECKSUM_COMPLETE) skb->csum = csum_sub(skb->csum, csum_partial(mac_header_end(skb), MPLS_HLEN, 0)); memmove(skb_mac_header(skb) + MPLS_HLEN, skb_mac_header(skb), skb->mac_len); __skb_pull(skb, MPLS_HLEN); skb_reset_mac_header(skb); /* mac_header_end() is used to locate the ethertype * field correctly in the presence of VLAN tags. */ hdr = (struct ethhdr *)(mac_header_end(skb) - ETH_HLEN); hdr->h_proto = ethertype; if (eth_p_mpls(skb->protocol)) skb->protocol = ethertype; return 0; }
static __wsum lro_tcp_data_csum(struct iphdr *iph, struct tcphdr *tcph, int len) { __wsum tcp_csum; __wsum tcp_hdr_csum; __wsum tcp_ps_hdr_csum; tcp_csum = ~csum_unfold(tcph->check); tcp_hdr_csum = csum_partial((u8 *)tcph, TCP_HDR_LEN(tcph), tcp_csum); tcp_ps_hdr_csum = csum_tcpudp_nofold(iph->saddr, iph->daddr, len + TCP_HDR_LEN(tcph), IPPROTO_TCP, 0); return csum_sub(csum_sub(tcp_csum, tcp_hdr_csum), tcp_ps_hdr_csum); }
static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, unsigned int len, u_int8_t protocol) { struct ipv6hdr *ip6h = ipv6_hdr(skb); __wsum hsum; __sum16 csum = 0; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: if (len == skb->len - dataoff) return nf_ip6_checksum(skb, hook, dataoff, protocol); /* fall through */ case CHECKSUM_NONE: hsum = skb_checksum(skb, 0, dataoff, 0); skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb->len - dataoff, protocol, csum_sub(0, hsum))); skb->ip_summed = CHECKSUM_NONE; return __skb_checksum_complete_head(skb, dataoff + len); } return csum; };
static int ip6t_npt_checkentry(const struct xt_tgchk_param *par) { struct ip6t_npt_tginfo *npt = par->targinfo; __wsum src_sum = 0, dst_sum = 0; struct in6_addr pfx; unsigned int i; if (npt->src_pfx_len > 64 || npt->dst_pfx_len > 64) return -EINVAL; /* Ensure that LSB of prefix is zero */ ipv6_addr_prefix(&pfx, &npt->src_pfx.in6, npt->src_pfx_len); if (!ipv6_addr_equal(&pfx, &npt->src_pfx.in6)) return -EINVAL; ipv6_addr_prefix(&pfx, &npt->dst_pfx.in6, npt->dst_pfx_len); if (!ipv6_addr_equal(&pfx, &npt->dst_pfx.in6)) return -EINVAL; for (i = 0; i < ARRAY_SIZE(npt->src_pfx.in6.s6_addr16); i++) { src_sum = csum_add(src_sum, (__force __wsum)npt->src_pfx.in6.s6_addr16[i]); dst_sum = csum_add(dst_sum, (__force __wsum)npt->dst_pfx.in6.s6_addr16[i]); } npt->adjustment = ~csum_fold(csum_sub(src_sum, dst_sum)); return 0; }
/* remove VLAN header from packet and update csum accordingly. */ static int __pop_vlan_tci(struct sk_buff *skb, __be16 *current_tci) { struct vlan_hdr *vhdr; int err; err = make_writable(skb, VLAN_ETH_HLEN); if (unlikely(err)) return err; if (get_ip_summed(skb) == OVS_CSUM_COMPLETE) skb->csum = csum_sub(skb->csum, csum_partial(skb->data + ETH_HLEN, VLAN_HLEN, 0)); vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN); *current_tci = vhdr->h_vlan_TCI; memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN); __skb_pull(skb, VLAN_HLEN); vlan_set_encap_proto(skb, vhdr); skb->mac_header += VLAN_HLEN; skb_reset_mac_len(skb); return 0; }
static void udpencap_fix4(struct sk_buff *skb, const struct xt_udpencap_tginfo *info) { struct iphdr *iph = ip_hdr(skb); bool fix_csum = (skb->ip_summed == CHECKSUM_COMPLETE && !info->encap); __be16 newlen = htons(ntohs(iph->tot_len) + (info->encap ? 1 : -1) * sizeof(struct udphdr)); if (fix_csum) { skb->csum = csum_sub(skb->csum, csum_partial(&iph->tot_len, 2, 0)); skb->csum = csum_sub(skb->csum, csum_partial(&iph->protocol, 3, 0)); } csum_replace2(&iph->check, iph->tot_len, newlen); iph->tot_len = newlen; if (iph->protocol != info->proto) { csum_replace2(&iph->check, htons(iph->protocol), htons(info->proto)); iph->protocol = info->proto; } if (fix_csum) { skb->csum = csum_add(skb->csum, csum_partial(&iph->tot_len, 2, 0)); skb->csum = csum_add(skb->csum, csum_partial(&iph->protocol, 3, 0)); } }
static void udpencap_fix6(struct sk_buff *skb, const struct xt_udpencap_tginfo *info) { struct ipv6hdr *iph = ipv6_hdr(skb); bool fix_csum = (skb->ip_summed == CHECKSUM_COMPLETE && !info->encap); if (fix_csum) skb->csum = csum_sub(skb->csum, csum_partial(&iph->payload_len, 3, 0)); iph->payload_len = htons(ntohs(iph->payload_len) + (info->encap ? 1 : -1) * sizeof(struct udphdr)); iph->nexthdr = info->proto; if (fix_csum) skb->csum = csum_add(skb->csum, csum_partial(&iph->payload_len, 3, 0)); }
static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb, int offset) { __wsum csum = skb->csum; if (skb->ip_summed != CHECKSUM_COMPLETE) return; if (offset != 0) csum = csum_sub(csum, csum_partial(skb->data, offset, 0)); put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum); }
static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb, int tlen, int offset) { __wsum csum = skb->csum; if (skb->ip_summed != CHECKSUM_COMPLETE) return; if (offset != 0) { int tend_off = skb_transport_offset(skb) + tlen; csum = csum_sub(csum, skb_checksum(skb, tend_off, offset, 0)); } put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum); }
/* Compute the whole skb csum in s/w and store it, then verify GRO csum * starting from gro_offset. */ static __sum16 gro_skb_checksum(struct sk_buff *skb) { __sum16 sum; skb->csum = skb_checksum(skb, 0, skb->len, 0); NAPI_GRO_CB(skb)->csum = csum_sub(skb->csum, csum_partial(skb->data, skb_gro_offset(skb), 0)); sum = csum_fold(NAPI_GRO_CB(skb)->csum); if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE)) { if (unlikely(!sum)) netdev_rx_csum_fault(skb->dev); } else skb->ip_summed = CHECKSUM_COMPLETE; return sum; }
static int set_eth_addr(struct sk_buff *skb, const struct ovs_key_ethernet *eth_key) { int err; err = make_writable(skb, ETH_HLEN); if (unlikely(err)) return err; if (get_ip_summed(skb) == OVS_CSUM_COMPLETE) skb->csum = csum_sub(skb->csum, csum_partial(eth_hdr(skb), ETH_ALEN * 2, 0)); memcpy(eth_hdr(skb)->h_source, eth_key->eth_src, ETH_ALEN); memcpy(eth_hdr(skb)->h_dest, eth_key->eth_dst, ETH_ALEN); if (get_ip_summed(skb) == OVS_CSUM_COMPLETE) skb->csum = csum_add(skb->csum, csum_partial(eth_hdr(skb), ETH_ALEN * 2, 0)); return 0; }
static int ip6t_npt_checkentry(const struct xt_tgchk_param *par) { struct ip6t_npt_tginfo *npt = par->targinfo; struct in6_addr pfx; __wsum src_sum, dst_sum; if (npt->src_pfx_len > 64 || npt->dst_pfx_len > 64) return -EINVAL; /* Ensure that LSB of prefix is zero */ ipv6_addr_prefix(&pfx, &npt->src_pfx.in6, npt->src_pfx_len); if (!ipv6_addr_equal(&pfx, &npt->src_pfx.in6)) return -EINVAL; ipv6_addr_prefix(&pfx, &npt->dst_pfx.in6, npt->dst_pfx_len); if (!ipv6_addr_equal(&pfx, &npt->dst_pfx.in6)) return -EINVAL; src_sum = csum_partial(&npt->src_pfx.in6, sizeof(npt->src_pfx.in6), 0); dst_sum = csum_partial(&npt->dst_pfx.in6, sizeof(npt->dst_pfx.in6), 0); npt->adjustment = ~csum_fold(csum_sub(src_sum, dst_sum)); return 0; }
void bpf_store_bits(struct bpf_context *pctx, u32 off, const void *from, u32 len) { struct bpf_dp_context *ctx = container_of(pctx, struct bpf_dp_context, context); struct sk_buff *skb = ctx->skb; if (unlikely(!skb)) return; if (!pskb_may_pull(skb, off + len)) return; if (skb->ip_summed == CHECKSUM_COMPLETE) skb->csum = csum_sub(skb->csum, csum_partial(skb->data + off, len, 0)); memcpy(skb->data + off, from, len); if (skb->ip_summed == CHECKSUM_COMPLETE) skb->csum = csum_add(skb->csum, csum_partial(skb->data + off, len, 0)); }
int ip6_route_me_harder(struct sk_buff *skb) { struct net *net = dev_net(skb_dst(skb)->dev); const struct ipv6hdr *iph = ipv6_hdr(skb); unsigned int hh_len; struct dst_entry *dst; struct flowi6 fl6 = { .flowi6_oif = skb->sk ? skb->sk->sk_bound_dev_if : 0, .flowi6_mark = skb->mark, .daddr = iph->daddr, .saddr = iph->saddr, }; int err; dst = ip6_route_output(net, skb->sk, &fl6); err = dst->error; if (err) { IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); net_dbg_ratelimited("ip6_route_me_harder: No more route\n"); dst_release(dst); return err; } /* Drop old route. */ skb_dst_drop(skb); skb_dst_set(skb, dst); #ifdef CONFIG_XFRM if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && xfrm_decode_session(skb, flowi6_to_flowi(&fl6), AF_INET6) == 0) { skb_dst_set(skb, NULL); dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0); if (IS_ERR(dst)) return PTR_ERR(dst); skb_dst_set(skb, dst); } #endif /* Change in oif may mean change in hh_len. */ hh_len = skb_dst(skb)->dev->hard_header_len; if (skb_headroom(skb) < hh_len && pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), 0, GFP_ATOMIC)) return -ENOMEM; return 0; } EXPORT_SYMBOL(ip6_route_me_harder); /* * Extra routing may needed on local out, as the QUEUE target never * returns control to the table. */ struct ip6_rt_info { struct in6_addr daddr; struct in6_addr saddr; u_int32_t mark; }; static void nf_ip6_saveroute(const struct sk_buff *skb, struct nf_queue_entry *entry) { struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); if (entry->hook == NF_INET_LOCAL_OUT) { const struct ipv6hdr *iph = ipv6_hdr(skb); rt_info->daddr = iph->daddr; rt_info->saddr = iph->saddr; rt_info->mark = skb->mark; } } static int nf_ip6_reroute(struct sk_buff *skb, const struct nf_queue_entry *entry) { struct ip6_rt_info *rt_info = nf_queue_entry_reroute(entry); if (entry->hook == NF_INET_LOCAL_OUT) { const struct ipv6hdr *iph = ipv6_hdr(skb); if (!ipv6_addr_equal(&iph->daddr, &rt_info->daddr) || !ipv6_addr_equal(&iph->saddr, &rt_info->saddr) || skb->mark != rt_info->mark) return ip6_route_me_harder(skb); } return 0; } static int nf_ip6_route(struct net *net, struct dst_entry **dst, struct flowi *fl, bool strict) { static const struct ipv6_pinfo fake_pinfo; static const struct inet_sock fake_sk = { /* makes ip6_route_output set RT6_LOOKUP_F_IFACE: */ .sk.sk_bound_dev_if = 1, .pinet6 = (struct ipv6_pinfo *) &fake_pinfo, }; const void *sk = strict ? &fake_sk : NULL; struct dst_entry *result; int err; result = ip6_route_output(net, sk, &fl->u.ip6); err = result->error; if (err) dst_release(result); else *dst = result; return err; } __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, u_int8_t protocol) { const struct ipv6hdr *ip6h = ipv6_hdr(skb); __sum16 csum = 0; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: if (hook != NF_INET_PRE_ROUTING && hook != NF_INET_LOCAL_IN) break; if (!csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb->len - dataoff, protocol, csum_sub(skb->csum, skb_checksum(skb, 0, dataoff, 0)))) { skb->ip_summed = CHECKSUM_UNNECESSARY; break; } /* fall through */ case CHECKSUM_NONE: skb->csum = ~csum_unfold( csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb->len - dataoff, protocol, csum_sub(0, skb_checksum(skb, 0, dataoff, 0)))); csum = __skb_checksum_complete(skb); } return csum; } EXPORT_SYMBOL(nf_ip6_checksum); static __sum16 nf_ip6_checksum_partial(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, unsigned int len, u_int8_t protocol) { const struct ipv6hdr *ip6h = ipv6_hdr(skb); __wsum hsum; __sum16 csum = 0; switch (skb->ip_summed) { case CHECKSUM_COMPLETE: if (len == skb->len - dataoff) return nf_ip6_checksum(skb, hook, dataoff, protocol); /* fall through */ case CHECKSUM_NONE: hsum = skb_checksum(skb, 0, dataoff, 0); skb->csum = ~csum_unfold(csum_ipv6_magic(&ip6h->saddr, &ip6h->daddr, skb->len - dataoff, protocol, csum_sub(0, hsum))); skb->ip_summed = CHECKSUM_NONE; return __skb_checksum_complete_head(skb, dataoff + len); } return csum; }; static const struct nf_ipv6_ops ipv6ops = { .chk_addr = ipv6_chk_addr, }; static const struct nf_afinfo nf_ip6_afinfo = { .family = AF_INET6, .checksum = nf_ip6_checksum, .checksum_partial = nf_ip6_checksum_partial, .route = nf_ip6_route, .saveroute = nf_ip6_saveroute, .reroute = nf_ip6_reroute, .route_key_size = sizeof(struct ip6_rt_info), }; int __init ipv6_netfilter_init(void) { RCU_INIT_POINTER(nf_ipv6_ops, &ipv6ops); return nf_register_afinfo(&nf_ip6_afinfo); } /* This can be called from inet6_init() on errors, so it cannot * be marked __exit. -DaveM */ void ipv6_netfilter_fini(void) { RCU_INIT_POINTER(nf_ipv6_ops, NULL); nf_unregister_afinfo(&nf_ip6_afinfo); }
int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi6 *fl6, struct rt6_info *rt, unsigned int flags, int dontfrag) { struct inet_sock *inet = inet_sk(sk); struct ipv6_pinfo *np = inet6_sk(sk); struct inet_cork *cork; struct sk_buff *skb, *skb_prev = NULL; unsigned int maxfraglen, fragheaderlen; int exthdrlen; int hh_len; int mtu; int copy; int err; int offset = 0; int csummode = CHECKSUM_NONE; __u8 tx_flags = 0; if (flags&MSG_PROBE) return 0; cork = &inet->cork.base; if (skb_queue_empty(&sk->sk_write_queue)) { /* * setup for corking */ if (opt) { if (WARN_ON(np->cork.opt)) return -EINVAL; np->cork.opt = kzalloc(opt->tot_len, sk->sk_allocation); if (unlikely(np->cork.opt == NULL)) return -ENOBUFS; np->cork.opt->tot_len = opt->tot_len; np->cork.opt->opt_flen = opt->opt_flen; np->cork.opt->opt_nflen = opt->opt_nflen; np->cork.opt->dst0opt = ip6_opt_dup(opt->dst0opt, sk->sk_allocation); if (opt->dst0opt && !np->cork.opt->dst0opt) return -ENOBUFS; np->cork.opt->dst1opt = ip6_opt_dup(opt->dst1opt, sk->sk_allocation); if (opt->dst1opt && !np->cork.opt->dst1opt) return -ENOBUFS; np->cork.opt->hopopt = ip6_opt_dup(opt->hopopt, sk->sk_allocation); if (opt->hopopt && !np->cork.opt->hopopt) return -ENOBUFS; np->cork.opt->srcrt = ip6_rthdr_dup(opt->srcrt, sk->sk_allocation); if (opt->srcrt && !np->cork.opt->srcrt) return -ENOBUFS; /* need source address above miyazawa*/ } dst_hold(&rt->dst); cork->dst = &rt->dst; inet->cork.fl.u.ip6 = *fl6; np->cork.hop_limit = hlimit; np->cork.tclass = tclass; if (rt->dst.flags & DST_XFRM_TUNNEL) mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ? rt->dst.dev->mtu : dst_mtu(&rt->dst); else mtu = np->pmtudisc == IPV6_PMTUDISC_PROBE ? rt->dst.dev->mtu : dst_mtu(rt->dst.path); if (np->frag_size < mtu) { if (np->frag_size) mtu = np->frag_size; } cork->fragsize = mtu; if (dst_allfrag(rt->dst.path)) cork->flags |= IPCORK_ALLFRAG; cork->length = 0; sk->sk_sndmsg_page = NULL; sk->sk_sndmsg_off = 0; exthdrlen = rt->dst.header_len + (opt ? opt->opt_flen : 0) - rt->rt6i_nfheader_len; length += exthdrlen; transhdrlen += exthdrlen; } else { rt = (struct rt6_info *)cork->dst; fl6 = &inet->cork.fl.u.ip6; opt = np->cork.opt; transhdrlen = 0; exthdrlen = 0; mtu = cork->fragsize; } hh_len = LL_RESERVED_SPACE(rt->dst.dev); fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len + (opt ? opt->opt_nflen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { if (cork->length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { ipv6_local_error(sk, EMSGSIZE, fl6, mtu-exthdrlen); return -EMSGSIZE; } } /* For UDP, check if TX timestamp is enabled */ if (sk->sk_type == SOCK_DGRAM) { err = sock_tx_timestamp(sk, &tx_flags); if (err) goto error; } /* * Let's try using as much space as possible. * Use MTU if total length of the message fits into the MTU. * Otherwise, we need to reserve fragment header and * fragment alignment (= 8-15 octects, in total). * * Note that we may need to "move" the data from the tail of * of the buffer to the new fragment when we split * the message. * * FIXME: It may be fragmented into multiple chunks * at once if non-fragmentable extension headers * are too large. * --yoshfuji */ cork->length += length; if (length > mtu) { int proto = sk->sk_protocol; if (dontfrag && (proto == IPPROTO_UDP || proto == IPPROTO_RAW)){ ipv6_local_rxpmtu(sk, fl6, mtu-exthdrlen); return -EMSGSIZE; } if (proto == IPPROTO_UDP && (rt->dst.dev->features & NETIF_F_UFO)) { err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len, fragheaderlen, transhdrlen, mtu, flags, rt); if (err) goto error; return 0; } } if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) goto alloc_new_skb; while (length > 0) { /* Check if the remaining data fits into current packet. */ copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; if (copy < length) copy = maxfraglen - skb->len; if (copy <= 0) { char *data; unsigned int datalen; unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; alloc_new_skb: /* There's no room in the current skb */ if (skb) fraggap = skb->len - maxfraglen; else fraggap = 0; /* update mtu and maxfraglen if necessary */ if (skb == NULL || skb_prev == NULL) ip6_append_data_mtu(&mtu, &maxfraglen, fragheaderlen, skb, rt); skb_prev = skb; /* * If remaining data exceeds the mtu, * we know we need more fragment(s). */ datalen = length + fraggap; if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len; if ((flags & MSG_MORE) && !(rt->dst.dev->features&NETIF_F_SG)) alloclen = mtu; else alloclen = datalen + fragheaderlen; if (datalen != length + fraggap) { /* * this is not the last fragment, the trailer * space is regarded as data space. */ datalen += rt->dst.trailer_len; } alloclen += rt->dst.trailer_len; fraglen = datalen + fragheaderlen; /* * We just reserve space for fragment header. * Note: this may be overallocation if the message * (without MSG_MORE) fits into the MTU. */ alloclen += sizeof(struct frag_hdr); if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len, (flags & MSG_DONTWAIT), &err); } else { skb = NULL; if (atomic_read(&sk->sk_wmem_alloc) <= 2 * sk->sk_sndbuf) skb = sock_wmalloc(sk, alloclen + hh_len, 1, sk->sk_allocation); if (unlikely(skb == NULL)) err = -ENOBUFS; else { /* Only the initial fragment * is time stamped. */ tx_flags = 0; } } if (skb == NULL) goto error; /* * Fill in the control structures */ skb->ip_summed = csummode; skb->csum = 0; /* reserve for fragmentation */ skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); if (sk->sk_type == SOCK_DGRAM) skb_shinfo(skb)->tx_flags = tx_flags; /* * Find where to start putting bytes */ data = skb_put(skb, fraglen); skb_set_network_header(skb, exthdrlen); data += fragheaderlen; skb->transport_header = (skb->network_header + fragheaderlen); if (fraggap) { skb->csum = skb_copy_and_csum_bits( skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy < 0) { err = -EINVAL; kfree_skb(skb); goto error; } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; } offset += copy; length -= datalen - fraggap; transhdrlen = 0; exthdrlen = 0; csummode = CHECKSUM_NONE; /* * Put the packet on the pending queue */ __skb_queue_tail(&sk->sk_write_queue, skb); continue; } if (copy > length) copy = length; if (!(rt->dst.dev->features&NETIF_F_SG)) { unsigned int off; off = skb->len; if (getfrag(from, skb_put(skb, copy), offset, copy, off, skb) < 0) { __skb_trim(skb, off); err = -EFAULT; goto error; } } else { int i = skb_shinfo(skb)->nr_frags; skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; struct page *page = sk->sk_sndmsg_page; int off = sk->sk_sndmsg_off; unsigned int left; if (page && (left = PAGE_SIZE - off) > 0) { if (copy >= left) copy = left; if (page != frag->page) { if (i == MAX_SKB_FRAGS) { err = -EMSGSIZE; goto error; } get_page(page); skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); frag = &skb_shinfo(skb)->frags[i]; } } else if(i < MAX_SKB_FRAGS) { if (copy > PAGE_SIZE) copy = PAGE_SIZE; page = alloc_pages(sk->sk_allocation, 0); if (page == NULL) { err = -ENOMEM; goto error; } sk->sk_sndmsg_page = page; sk->sk_sndmsg_off = 0; skb_fill_page_desc(skb, i, page, 0, 0); frag = &skb_shinfo(skb)->frags[i]; } else { err = -EMSGSIZE; goto error; } if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { err = -EFAULT; goto error; } sk->sk_sndmsg_off += copy; frag->size += copy; skb->len += copy; skb->data_len += copy; skb->truesize += copy; atomic_add(copy, &sk->sk_wmem_alloc); } offset += copy; length -= copy; } return 0; error: cork->length -= length; IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); return err; }
static int __ip6_append_data(struct sock *sk, struct flowi6 *fl6, struct sk_buff_head *queue, struct inet_cork *cork, struct inet6_cork *v6_cork, struct page_frag *pfrag, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, unsigned int flags, int dontfrag) { struct sk_buff *skb, *skb_prev = NULL; unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu; int exthdrlen = 0; int dst_exthdrlen = 0; int hh_len; int copy; int err; int offset = 0; __u8 tx_flags = 0; u32 tskey = 0; struct rt6_info *rt = (struct rt6_info *)cork->dst; struct ipv6_txoptions *opt = v6_cork->opt; int csummode = CHECKSUM_NONE; unsigned int maxnonfragsize, headersize; skb = skb_peek_tail(queue); if (!skb) { exthdrlen = opt ? opt->opt_flen : 0; dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len; } mtu = cork->fragsize; orig_mtu = mtu; hh_len = LL_RESERVED_SPACE(rt->dst.dev); fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len + (opt ? opt->opt_nflen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); headersize = sizeof(struct ipv6hdr) + (opt ? opt->opt_flen + opt->opt_nflen : 0) + (dst_allfrag(&rt->dst) ? sizeof(struct frag_hdr) : 0) + rt->rt6i_nfheader_len; if (cork->length + length > mtu - headersize && dontfrag && (sk->sk_protocol == IPPROTO_UDP || sk->sk_protocol == IPPROTO_RAW)) { ipv6_local_rxpmtu(sk, fl6, mtu - headersize + sizeof(struct ipv6hdr)); goto emsgsize; } if (ip6_sk_ignore_df(sk)) maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN; else maxnonfragsize = mtu; if (cork->length + length > maxnonfragsize - headersize) { emsgsize: ipv6_local_error(sk, EMSGSIZE, fl6, mtu - headersize + sizeof(struct ipv6hdr)); return -EMSGSIZE; } /* CHECKSUM_PARTIAL only with no extension headers and when * we are not going to fragment */ if (transhdrlen && sk->sk_protocol == IPPROTO_UDP && headersize == sizeof(struct ipv6hdr) && length < mtu - headersize && !(flags & MSG_MORE) && rt->dst.dev->features & NETIF_F_V6_CSUM) csummode = CHECKSUM_PARTIAL; if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) { sock_tx_timestamp(sk, &tx_flags); if (tx_flags & SKBTX_ANY_SW_TSTAMP && sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID) tskey = sk->sk_tskey++; } /* * Let's try using as much space as possible. * Use MTU if total length of the message fits into the MTU. * Otherwise, we need to reserve fragment header and * fragment alignment (= 8-15 octects, in total). * * Note that we may need to "move" the data from the tail of * of the buffer to the new fragment when we split * the message. * * FIXME: It may be fragmented into multiple chunks * at once if non-fragmentable extension headers * are too large. * --yoshfuji */ cork->length += length; if (((length > mtu) || (skb && skb_is_gso(skb))) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO) && (sk->sk_type == SOCK_DGRAM) && !udp_get_no_check6_tx(sk)) { err = ip6_ufo_append_data(sk, queue, getfrag, from, length, hh_len, fragheaderlen, exthdrlen, transhdrlen, mtu, flags, fl6); if (err) goto error; return 0; } if (!skb) goto alloc_new_skb; while (length > 0) { /* Check if the remaining data fits into current packet. */ copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; if (copy < length) copy = maxfraglen - skb->len; if (copy <= 0) { char *data; unsigned int datalen; unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; alloc_new_skb: /* There's no room in the current skb */ if (skb) fraggap = skb->len - maxfraglen; else fraggap = 0; /* update mtu and maxfraglen if necessary */ if (!skb || !skb_prev) ip6_append_data_mtu(&mtu, &maxfraglen, fragheaderlen, skb, rt, orig_mtu); skb_prev = skb; /* * If remaining data exceeds the mtu, * we know we need more fragment(s). */ datalen = length + fraggap; if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len; if ((flags & MSG_MORE) && !(rt->dst.dev->features&NETIF_F_SG)) alloclen = mtu; else alloclen = datalen + fragheaderlen; alloclen += dst_exthdrlen; if (datalen != length + fraggap) { /* * this is not the last fragment, the trailer * space is regarded as data space. */ datalen += rt->dst.trailer_len; } alloclen += rt->dst.trailer_len; fraglen = datalen + fragheaderlen; /* * We just reserve space for fragment header. * Note: this may be overallocation if the message * (without MSG_MORE) fits into the MTU. */ alloclen += sizeof(struct frag_hdr); if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len, (flags & MSG_DONTWAIT), &err); } else { skb = NULL; if (atomic_read(&sk->sk_wmem_alloc) <= 2 * sk->sk_sndbuf) skb = sock_wmalloc(sk, alloclen + hh_len, 1, sk->sk_allocation); if (unlikely(!skb)) err = -ENOBUFS; } if (!skb) goto error; /* * Fill in the control structures */ skb->protocol = htons(ETH_P_IPV6); skb->ip_summed = csummode; skb->csum = 0; /* reserve for fragmentation and ipsec header */ skb_reserve(skb, hh_len + sizeof(struct frag_hdr) + dst_exthdrlen); /* Only the initial fragment is time stamped */ skb_shinfo(skb)->tx_flags = tx_flags; tx_flags = 0; skb_shinfo(skb)->tskey = tskey; tskey = 0; /* * Find where to start putting bytes */ data = skb_put(skb, fraglen); skb_set_network_header(skb, exthdrlen); data += fragheaderlen; skb->transport_header = (skb->network_header + fragheaderlen); if (fraggap) { skb->csum = skb_copy_and_csum_bits( skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy < 0) { err = -EINVAL; kfree_skb(skb); goto error; } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; } offset += copy; length -= datalen - fraggap; transhdrlen = 0; exthdrlen = 0; dst_exthdrlen = 0; /* * Put the packet on the pending queue */ __skb_queue_tail(queue, skb); continue; } if (copy > length) copy = length; if (!(rt->dst.dev->features&NETIF_F_SG)) { unsigned int off; off = skb->len; if (getfrag(from, skb_put(skb, copy), offset, copy, off, skb) < 0) { __skb_trim(skb, off); err = -EFAULT; goto error; } } else { int i = skb_shinfo(skb)->nr_frags; err = -ENOMEM; if (!sk_page_frag_refill(sk, pfrag)) goto error; if (!skb_can_coalesce(skb, i, pfrag->page, pfrag->offset)) { err = -EMSGSIZE; if (i == MAX_SKB_FRAGS) goto error; __skb_fill_page_desc(skb, i, pfrag->page, pfrag->offset, 0); skb_shinfo(skb)->nr_frags = ++i; get_page(pfrag->page); } copy = min_t(int, copy, pfrag->size - pfrag->offset); if (getfrag(from, page_address(pfrag->page) + pfrag->offset, offset, copy, skb->len, skb) < 0) goto error_efault; pfrag->offset += copy; skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); skb->len += copy; skb->data_len += copy; skb->truesize += copy; atomic_add(copy, &sk->sk_wmem_alloc); } offset += copy; length -= copy; } return 0; error_efault: err = -EFAULT; error: cork->length -= length; IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS); return err; }
int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, int hlimit, struct ipv6_txoptions *opt, struct flowi *fl, struct rt6_info *rt, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); struct ipv6_pinfo *np = inet6_sk(sk); struct sk_buff *skb; unsigned int maxfraglen, fragheaderlen; int exthdrlen; int hh_len; int mtu; int copy; int err; int offset = 0; int csummode = CHECKSUM_NONE; if (flags&MSG_PROBE) return 0; if (skb_queue_empty(&sk->sk_write_queue)) { /* * setup for corking */ if (opt) { if (np->cork.opt == NULL) { np->cork.opt = kmalloc(opt->tot_len, sk->sk_allocation); if (unlikely(np->cork.opt == NULL)) return -ENOBUFS; } else if (np->cork.opt->tot_len < opt->tot_len) { printk(KERN_DEBUG "ip6_append_data: invalid option length\n"); return -EINVAL; } memcpy(np->cork.opt, opt, opt->tot_len); inet->cork.flags |= IPCORK_OPT; /* need source address above miyazawa*/ } dst_hold(&rt->u.dst); np->cork.rt = rt; inet->cork.fl = *fl; np->cork.hop_limit = hlimit; inet->cork.fragsize = mtu = dst_mtu(rt->u.dst.path); if (dst_allfrag(rt->u.dst.path)) inet->cork.flags |= IPCORK_ALLFRAG; inet->cork.length = 0; sk->sk_sndmsg_page = NULL; sk->sk_sndmsg_off = 0; exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0); length += exthdrlen; transhdrlen += exthdrlen; } else { rt = np->cork.rt; fl = &inet->cork.fl; if (inet->cork.flags & IPCORK_OPT) opt = np->cork.opt; transhdrlen = 0; exthdrlen = 0; mtu = inet->cork.fragsize; } hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); fragheaderlen = sizeof(struct ipv6hdr) + (opt ? opt->opt_nflen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); return -EMSGSIZE; } } /* * Let's try using as much space as possible. * Use MTU if total length of the message fits into the MTU. * Otherwise, we need to reserve fragment header and * fragment alignment (= 8-15 octects, in total). * * Note that we may need to "move" the data from the tail of * of the buffer to the new fragment when we split * the message. * * FIXME: It may be fragmented into multiple chunks * at once if non-fragmentable extension headers * are too large. * --yoshfuji */ inet->cork.length += length; if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) goto alloc_new_skb; while (length > 0) { /* Check if the remaining data fits into current packet. */ copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; if (copy < length) copy = maxfraglen - skb->len; if (copy <= 0) { char *data; unsigned int datalen; unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; struct sk_buff *skb_prev; alloc_new_skb: skb_prev = skb; /* There's no room in the current skb */ if (skb_prev) fraggap = skb_prev->len - maxfraglen; else fraggap = 0; /* * If remaining data exceeds the mtu, * we know we need more fragment(s). */ datalen = length + fraggap; if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) datalen = maxfraglen - fragheaderlen; fraglen = datalen + fragheaderlen; if ((flags & MSG_MORE) && !(rt->u.dst.dev->features&NETIF_F_SG)) alloclen = mtu; else alloclen = datalen + fragheaderlen; /* * The last fragment gets additional space at tail. * Note: we overallocate on fragments with MSG_MODE * because we have no idea if we're the last one. */ if (datalen == length + fraggap) alloclen += rt->u.dst.trailer_len; /* * We just reserve space for fragment header. * Note: this may be overallocation if the message * (without MSG_MORE) fits into the MTU. */ alloclen += sizeof(struct frag_hdr); if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len, (flags & MSG_DONTWAIT), &err); } else { skb = NULL; if (atomic_read(&sk->sk_wmem_alloc) <= 2 * sk->sk_sndbuf) skb = sock_wmalloc(sk, alloclen + hh_len, 1, sk->sk_allocation); if (unlikely(skb == NULL)) err = -ENOBUFS; } if (skb == NULL) goto error; /* * Fill in the control structures */ skb->ip_summed = csummode; skb->csum = 0; /* reserve for fragmentation */ skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); /* * Find where to start putting bytes */ data = skb_put(skb, fraglen); skb->nh.raw = data + exthdrlen; data += fragheaderlen; skb->h.raw = data + exthdrlen; if (fraggap) { skb->csum = skb_copy_and_csum_bits( skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; skb_trim(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy < 0) { err = -EINVAL; kfree_skb(skb); goto error; } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; } offset += copy; length -= datalen - fraggap; transhdrlen = 0; exthdrlen = 0; csummode = CHECKSUM_NONE; /* * Put the packet on the pending queue */ __skb_queue_tail(&sk->sk_write_queue, skb); continue; } if (copy > length) copy = length; if (!(rt->u.dst.dev->features&NETIF_F_SG)) { unsigned int off; off = skb->len; if (getfrag(from, skb_put(skb, copy), offset, copy, off, skb) < 0) { __skb_trim(skb, off); err = -EFAULT; goto error; } } else { int i = skb_shinfo(skb)->nr_frags; skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; struct page *page = sk->sk_sndmsg_page; int off = sk->sk_sndmsg_off; unsigned int left; if (page && (left = PAGE_SIZE - off) > 0) { if (copy >= left) copy = left; if (page != frag->page) { if (i == MAX_SKB_FRAGS) { err = -EMSGSIZE; goto error; } get_page(page); skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); frag = &skb_shinfo(skb)->frags[i]; } } else if(i < MAX_SKB_FRAGS) { if (copy > PAGE_SIZE) copy = PAGE_SIZE; page = alloc_pages(sk->sk_allocation, 0); if (page == NULL) { err = -ENOMEM; goto error; } sk->sk_sndmsg_page = page; sk->sk_sndmsg_off = 0; skb_fill_page_desc(skb, i, page, 0, 0); frag = &skb_shinfo(skb)->frags[i]; skb->truesize += PAGE_SIZE; atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc); } else { err = -EMSGSIZE; goto error; } if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { err = -EFAULT; goto error; } sk->sk_sndmsg_off += copy; frag->size += copy; skb->len += copy; skb->data_len += copy; } offset += copy; length -= copy; } return 0; error: inet->cork.length -= length; IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); return err; }
static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff) { struct sk_buff *prev, *next; int offset, end; if (fq->last_in & COMPLETE) goto err; offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(skb->nh.ipv6h->payload_len) - ((u8 *) (fhdr + 1) - (u8 *) (skb->nh.ipv6h + 1))); if ((unsigned int)end >= 65536) { icmpv6_param_prob(skb,ICMPV6_HDR_FIELD, (u8*)&fhdr->frag_off - skb->nh.raw); return; } if (skb->ip_summed == CHECKSUM_HW) skb->csum = csum_sub(skb->csum, csum_partial(skb->nh.raw, (u8*)(fhdr+1)-skb->nh.raw, 0)); /* Is this the final fragment? */ if (!(fhdr->frag_off & __constant_htons(0x0001))) { /* If we already have some bits beyond end * or have different end, the segment is corrupted. */ if (end < fq->len || ((fq->last_in & LAST_IN) && end != fq->len)) goto err; fq->last_in |= LAST_IN; fq->len = end; } else { /* Check if the fragment is rounded to 8 bytes. * Required by the RFC. */ if (end & 0x7) { /* RFC2460 says always send parameter problem in * this case. -DaveM */ icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, offsetof(struct ipv6hdr, payload_len)); return; } if (end > fq->len) { /* Some bits beyond end -> corruption. */ if (fq->last_in & LAST_IN) goto err; fq->len = end; } } if (end == offset) goto err; /* Point into the IP datagram 'data' part. */ if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) goto err; if (end-offset < skb->len) { if (pskb_trim(skb, end - offset)) goto err; if (skb->ip_summed != CHECKSUM_UNNECESSARY) skb->ip_summed = CHECKSUM_NONE; } /* Find out which fragments are in front and at the back of us * in the chain of fragments so far. We must know where to put * this fragment, right? */ prev = NULL; for(next = fq->fragments; next != NULL; next = next->next) { if (FRAG6_CB(next)->offset >= offset) break; /* bingo! */ prev = next; } /* We found where to put this one. Check for overlap with * preceding fragment, and, if needed, align things so that * any overlaps are eliminated. */ if (prev) { int i = (FRAG6_CB(prev)->offset + prev->len) - offset; if (i > 0) { offset += i; if (end <= offset) goto err; if (!pskb_pull(skb, i)) goto err; if (skb->ip_summed != CHECKSUM_UNNECESSARY) skb->ip_summed = CHECKSUM_NONE; } } /* Look for overlap with succeeding segments. * If we can merge fragments, do it. */ while (next && FRAG6_CB(next)->offset < end) { int i = end - FRAG6_CB(next)->offset; /* overlap is 'i' bytes */ if (i < next->len) { /* Eat head of the next overlapped fragment * and leave the loop. The next ones cannot overlap. */ if (!pskb_pull(next, i)) goto err; FRAG6_CB(next)->offset += i; /* next fragment */ fq->meat -= i; if (next->ip_summed != CHECKSUM_UNNECESSARY) next->ip_summed = CHECKSUM_NONE; break; } else { struct sk_buff *free_it = next; /* Old fragmnet is completely overridden with * new one drop it. */ next = next->next; if (prev) prev->next = next; else fq->fragments = next; fq->meat -= free_it->len; frag_kfree_skb(free_it); } } FRAG6_CB(skb)->offset = offset; /* Insert this fragment in the chain of fragments. */ skb->next = next; if (prev) prev->next = skb; else fq->fragments = skb; if (skb->dev) fq->iif = skb->dev->ifindex; skb->dev = NULL; fq->stamp = skb->stamp; fq->meat += skb->len; atomic_add(skb->truesize, &ip6_frag_mem); /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ if (offset == 0) { fq->nhoffset = nhoff; fq->last_in |= FIRST_IN; } return; err: kfree_skb(skb); }
static int nf_ct_frag6_queue(struct nf_ct_frag6_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff) { struct sk_buff *prev, *next; int offset, end; if (fq->last_in & COMPLETE) { DEBUGP("Allready completed\n"); goto err; } offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(skb->nh.ipv6h->payload_len) - ((u8 *) (fhdr + 1) - (u8 *) (skb->nh.ipv6h + 1))); if ((unsigned int)end > IPV6_MAXPLEN) { DEBUGP("offset is too large.\n"); return -1; } if (skb->ip_summed == CHECKSUM_HW) skb->csum = csum_sub(skb->csum, csum_partial(skb->nh.raw, (u8*)(fhdr + 1) - skb->nh.raw, 0)); /* Is this the final fragment? */ if (!(fhdr->frag_off & htons(IP6_MF))) { /* If we already have some bits beyond end * or have different end, the segment is corrupted. */ if (end < fq->len || ((fq->last_in & LAST_IN) && end != fq->len)) { DEBUGP("already received last fragment\n"); goto err; } fq->last_in |= LAST_IN; fq->len = end; } else { /* Check if the fragment is rounded to 8 bytes. * Required by the RFC. */ if (end & 0x7) { /* RFC2460 says always send parameter problem in * this case. -DaveM */ DEBUGP("the end of this fragment is not rounded to 8 bytes.\n"); return -1; } if (end > fq->len) { /* Some bits beyond end -> corruption. */ if (fq->last_in & LAST_IN) { DEBUGP("last packet already reached.\n"); goto err; } fq->len = end; } } if (end == offset) goto err; /* Point into the IP datagram 'data' part. */ if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) { DEBUGP("queue: message is too short.\n"); goto err; } if (end-offset < skb->len) { if (pskb_trim(skb, end - offset)) { DEBUGP("Can't trim\n"); goto err; } if (skb->ip_summed != CHECKSUM_UNNECESSARY) skb->ip_summed = CHECKSUM_NONE; } /* Find out which fragments are in front and at the back of us * in the chain of fragments so far. We must know where to put * this fragment, right? */ prev = NULL; for (next = fq->fragments; next != NULL; next = next->next) { if (NFCT_FRAG6_CB(next)->offset >= offset) break; /* bingo! */ prev = next; } /* We found where to put this one. Check for overlap with * preceding fragment, and, if needed, align things so that * any overlaps are eliminated. */ if (prev) { int i = (NFCT_FRAG6_CB(prev)->offset + prev->len) - offset; if (i > 0) { offset += i; if (end <= offset) { DEBUGP("overlap\n"); goto err; } if (!pskb_pull(skb, i)) { DEBUGP("Can't pull\n"); goto err; } if (skb->ip_summed != CHECKSUM_UNNECESSARY) skb->ip_summed = CHECKSUM_NONE; } } /* Look for overlap with succeeding segments. * If we can merge fragments, do it. */ while (next && NFCT_FRAG6_CB(next)->offset < end) { /* overlap is 'i' bytes */ int i = end - NFCT_FRAG6_CB(next)->offset; if (i < next->len) { /* Eat head of the next overlapped fragment * and leave the loop. The next ones cannot overlap. */ DEBUGP("Eat head of the overlapped parts.: %d", i); if (!pskb_pull(next, i)) goto err; /* next fragment */ NFCT_FRAG6_CB(next)->offset += i; fq->meat -= i; if (next->ip_summed != CHECKSUM_UNNECESSARY) next->ip_summed = CHECKSUM_NONE; break; } else { struct sk_buff *free_it = next; /* Old fragmnet is completely overridden with * new one drop it. */ next = next->next; if (prev) prev->next = next; else fq->fragments = next; fq->meat -= free_it->len; frag_kfree_skb(free_it, NULL); } } NFCT_FRAG6_CB(skb)->offset = offset; /* Insert this fragment in the chain of fragments. */ skb->next = next; if (prev) prev->next = skb; else fq->fragments = skb; skb->dev = NULL; skb_get_timestamp(skb, &fq->stamp); fq->meat += skb->len; atomic_add(skb->truesize, &nf_ct_frag6_mem); /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ if (offset == 0) { fq->nhoffset = nhoff; fq->last_in |= FIRST_IN; } write_lock(&nf_ct_frag6_lock); list_move_tail(&fq->lru_list, &nf_ct_frag6_lru_list); write_unlock(&nf_ct_frag6_lock); return 0; err: return -1; }
static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff) { struct sk_buff *prev, *next; struct net_device *dev; int offset, end; struct net *net = dev_net(skb_dst(skb)->dev); if (fq->q.last_in & INET_FRAG_COMPLETE) goto err; offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); if ((unsigned int)end > IPV6_MAXPLEN) { IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, ((u8 *)&fhdr->frag_off - skb_network_header(skb))); return -1; } if (skb->ip_summed == CHECKSUM_COMPLETE) { const unsigned char *nh = skb_network_header(skb); skb->csum = csum_sub(skb->csum, csum_partial(nh, (u8 *)(fhdr + 1) - nh, 0)); } /* Is this the final fragment? */ if (!(fhdr->frag_off & htons(IP6_MF))) { /* If we already have some bits beyond end * or have different end, the segment is corrupted. */ if (end < fq->q.len || ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) goto err; fq->q.last_in |= INET_FRAG_LAST_IN; fq->q.len = end; } else { /* Check if the fragment is rounded to 8 bytes. * Required by the RFC. */ if (end & 0x7) { /* RFC2460 says always send parameter problem in * this case. -DaveM */ IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, offsetof(struct ipv6hdr, payload_len)); return -1; } if (end > fq->q.len) { /* Some bits beyond end -> corruption. */ if (fq->q.last_in & INET_FRAG_LAST_IN) goto err; fq->q.len = end; } } if (end == offset) goto err; /* Point into the IP datagram 'data' part. */ if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) goto err; if (pskb_trim_rcsum(skb, end - offset)) goto err; /* Find out which fragments are in front and at the back of us * in the chain of fragments so far. We must know where to put * this fragment, right? */ prev = fq->q.fragments_tail; if (!prev || FRAG6_CB(prev)->offset < offset) { next = NULL; goto found; } prev = NULL; for(next = fq->q.fragments; next != NULL; next = next->next) { if (FRAG6_CB(next)->offset >= offset) break; /* bingo! */ prev = next; } found: /* RFC5722, Section 4: * When reassembling an IPv6 datagram, if * one or more its constituent fragments is determined to be an * overlapping fragment, the entire datagram (and any constituent * fragments, including those not yet received) MUST be silently * discarded. */ /* Check for overlap with preceding fragment. */ if (prev && (FRAG6_CB(prev)->offset + prev->len) > offset) goto discard_fq; /* Look for overlap with succeeding segment. */ if (next && FRAG6_CB(next)->offset < end) goto discard_fq; FRAG6_CB(skb)->offset = offset; /* Insert this fragment in the chain of fragments. */ skb->next = next; if (!next) fq->q.fragments_tail = skb; if (prev) prev->next = skb; else fq->q.fragments = skb; dev = skb->dev; if (dev) { fq->iif = dev->ifindex; skb->dev = NULL; } fq->q.stamp = skb->tstamp; fq->q.meat += skb->len; atomic_add(skb->truesize, &fq->q.net->mem); /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ if (offset == 0) { fq->nhoffset = nhoff; fq->q.last_in |= INET_FRAG_FIRST_IN; } if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && fq->q.meat == fq->q.len) return ip6_frag_reasm(fq, prev, dev); write_lock(&ip6_frags.lock); list_move_tail(&fq->q.lru_list, &fq->q.net->lru_list); write_unlock(&ip6_frags.lock); return -1; discard_fq: fq_kill(fq); err: IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); kfree_skb(skb); return -1; }
static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff) { struct sk_buff *prev, *next; struct net_device *dev; int offset, end; struct net *net = dev_net(skb_dst(skb)->dev); if (fq->q.last_in & INET_FRAG_COMPLETE) goto err; offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); if ((unsigned int)end > IPV6_MAXPLEN) { IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, ((u8 *)&fhdr->frag_off - skb_network_header(skb))); return -1; } if (skb->ip_summed == CHECKSUM_COMPLETE) { const unsigned char *nh = skb_network_header(skb); skb->csum = csum_sub(skb->csum, csum_partial(nh, (u8 *)(fhdr + 1) - nh, 0)); } if (!(fhdr->frag_off & htons(IP6_MF))) { if (end < fq->q.len || ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) goto err; fq->q.last_in |= INET_FRAG_LAST_IN; fq->q.len = end; } else { if (end & 0x7) { IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, offsetof(struct ipv6hdr, payload_len)); return -1; } if (end > fq->q.len) { if (fq->q.last_in & INET_FRAG_LAST_IN) goto err; fq->q.len = end; } } if (end == offset) goto err; if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) goto err; if (pskb_trim_rcsum(skb, end - offset)) goto err; prev = fq->q.fragments_tail; if (!prev || FRAG6_CB(prev)->offset < offset) { next = NULL; goto found; } prev = NULL; for(next = fq->q.fragments; next != NULL; next = next->next) { if (FRAG6_CB(next)->offset >= offset) break; prev = next; } found: if (prev && (FRAG6_CB(prev)->offset + prev->len) > offset) goto discard_fq; if (next && FRAG6_CB(next)->offset < end) goto discard_fq; FRAG6_CB(skb)->offset = offset; skb->next = next; if (!next) fq->q.fragments_tail = skb; if (prev) prev->next = skb; else fq->q.fragments = skb; dev = skb->dev; if (dev) { fq->iif = dev->ifindex; skb->dev = NULL; } fq->q.stamp = skb->tstamp; fq->q.meat += skb->len; atomic_add(skb->truesize, &fq->q.net->mem); if (offset == 0) { fq->nhoffset = nhoff; fq->q.last_in |= INET_FRAG_FIRST_IN; } if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && fq->q.meat == fq->q.len) { int res; unsigned long orefdst = skb->_skb_refdst; skb->_skb_refdst = 0UL; res = ip6_frag_reasm(fq, prev, dev); skb->_skb_refdst = orefdst; return res; } skb_dst_drop(skb); write_lock(&ip6_frags.lock); list_move_tail(&fq->q.lru_list, &fq->q.net->lru_list); write_unlock(&ip6_frags.lock); return -1; discard_fq: fq_kill(fq); err: IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); kfree_skb(skb); return -1; }
static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff) { struct sk_buff *prev, *next; struct net_device *dev; int offset, end; if (fq->q.last_in & INET_FRAG_COMPLETE) goto err; offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); if ((unsigned int)end > IPV6_MAXPLEN) { IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, ((u8 *)&fhdr->frag_off - skb_network_header(skb))); return -1; } if (skb->ip_summed == CHECKSUM_COMPLETE) { const unsigned char *nh = skb_network_header(skb); skb->csum = csum_sub(skb->csum, csum_partial(nh, (u8 *)(fhdr + 1) - nh, 0)); } /* Is this the final fragment? */ if (!(fhdr->frag_off & htons(IP6_MF))) { /* If we already have some bits beyond end * or have different end, the segment is corrupted. */ if (end < fq->q.len || ((fq->q.last_in & INET_FRAG_LAST_IN) && end != fq->q.len)) goto err; fq->q.last_in |= INET_FRAG_LAST_IN; fq->q.len = end; } else { /* Check if the fragment is rounded to 8 bytes. * Required by the RFC. */ if (end & 0x7) { /* RFC2460 says always send parameter problem in * this case. -DaveM */ IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS); icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, offsetof(struct ipv6hdr, payload_len)); return -1; } if (end > fq->q.len) { /* Some bits beyond end -> corruption. */ if (fq->q.last_in & INET_FRAG_LAST_IN) goto err; fq->q.len = end; } } if (end == offset) goto err; /* Point into the IP datagram 'data' part. */ if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) goto err; if (pskb_trim_rcsum(skb, end - offset)) goto err; /* Find out which fragments are in front and at the back of us * in the chain of fragments so far. We must know where to put * this fragment, right? */ prev = NULL; for(next = fq->q.fragments; next != NULL; next = next->next) { if (FRAG6_CB(next)->offset >= offset) break; /* bingo! */ prev = next; } /* We found where to put this one. Check for overlap with * preceding fragment, and, if needed, align things so that * any overlaps are eliminated. */ if (prev) { int i = (FRAG6_CB(prev)->offset + prev->len) - offset; if (i > 0) { offset += i; if (end <= offset) goto err; if (!pskb_pull(skb, i)) goto err; if (skb->ip_summed != CHECKSUM_UNNECESSARY) skb->ip_summed = CHECKSUM_NONE; } } /* Look for overlap with succeeding segments. * If we can merge fragments, do it. */ while (next && FRAG6_CB(next)->offset < end) { int i = end - FRAG6_CB(next)->offset; /* overlap is 'i' bytes */ if (i < next->len) { /* Eat head of the next overlapped fragment * and leave the loop. The next ones cannot overlap. */ if (!pskb_pull(next, i)) goto err; FRAG6_CB(next)->offset += i; /* next fragment */ fq->q.meat -= i; if (next->ip_summed != CHECKSUM_UNNECESSARY) next->ip_summed = CHECKSUM_NONE; break; } else { struct sk_buff *free_it = next; /* Old fragment is completely overridden with * new one drop it. */ next = next->next; if (prev) prev->next = next; else fq->q.fragments = next; fq->q.meat -= free_it->len; frag_kfree_skb(fq->q.net, free_it, NULL); } } FRAG6_CB(skb)->offset = offset; /* Insert this fragment in the chain of fragments. */ skb->next = next; if (prev) prev->next = skb; else fq->q.fragments = skb; dev = skb->dev; if (dev) { fq->iif = dev->ifindex; skb->dev = NULL; } fq->q.stamp = skb->tstamp; fq->q.meat += skb->len; atomic_add(skb->truesize, &fq->q.net->mem); /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ if (offset == 0) { fq->nhoffset = nhoff; fq->q.last_in |= INET_FRAG_FIRST_IN; } if (fq->q.last_in == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && fq->q.meat == fq->q.len) return ip6_frag_reasm(fq, prev, dev); write_lock(&ip6_frags.lock); list_move_tail(&fq->q.lru_list, &fq->q.net->lru_list); write_unlock(&ip6_frags.lock); return -1; err: IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS); kfree_skb(skb); return -1; }
static struct frag_queue * fq_find(struct net *net, __be32 id, const struct ipv6hdr *hdr, int iif) { struct frag_v6_compare_key key = { .id = id, .saddr = hdr->saddr, .daddr = hdr->daddr, .user = IP6_DEFRAG_LOCAL_DELIVER, .iif = iif, }; struct inet_frag_queue *q; if (!(ipv6_addr_type(&hdr->daddr) & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL))) key.iif = 0; q = inet_frag_find(&net->ipv6.frags, &key); if (!q) return NULL; return container_of(q, struct frag_queue, q); } static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, struct frag_hdr *fhdr, int nhoff, u32 *prob_offset) { struct net *net = dev_net(skb_dst(skb)->dev); int offset, end, fragsize; struct sk_buff *prev_tail; struct net_device *dev; int err = -ENOENT; u8 ecn; if (fq->q.flags & INET_FRAG_COMPLETE) goto err; err = -EINVAL; offset = ntohs(fhdr->frag_off) & ~0x7; end = offset + (ntohs(ipv6_hdr(skb)->payload_len) - ((u8 *)(fhdr + 1) - (u8 *)(ipv6_hdr(skb) + 1))); if ((unsigned int)end > IPV6_MAXPLEN) { *prob_offset = (u8 *)&fhdr->frag_off - skb_network_header(skb); /* note that if prob_offset is set, the skb is freed elsewhere, * we do not free it here. */ return -1; } ecn = ip6_frag_ecn(ipv6_hdr(skb)); if (skb->ip_summed == CHECKSUM_COMPLETE) { const unsigned char *nh = skb_network_header(skb); skb->csum = csum_sub(skb->csum, csum_partial(nh, (u8 *)(fhdr + 1) - nh, 0)); } /* Is this the final fragment? */ if (!(fhdr->frag_off & htons(IP6_MF))) { /* If we already have some bits beyond end * or have different end, the segment is corrupted. */ if (end < fq->q.len || ((fq->q.flags & INET_FRAG_LAST_IN) && end != fq->q.len)) goto discard_fq; fq->q.flags |= INET_FRAG_LAST_IN; fq->q.len = end; } else { /* Check if the fragment is rounded to 8 bytes. * Required by the RFC. */ if (end & 0x7) { /* RFC2460 says always send parameter problem in * this case. -DaveM */ *prob_offset = offsetof(struct ipv6hdr, payload_len); return -1; } if (end > fq->q.len) { /* Some bits beyond end -> corruption. */ if (fq->q.flags & INET_FRAG_LAST_IN) goto discard_fq; fq->q.len = end; } } if (end == offset) goto discard_fq; err = -ENOMEM; /* Point into the IP datagram 'data' part. */ if (!pskb_pull(skb, (u8 *) (fhdr + 1) - skb->data)) goto discard_fq; err = pskb_trim_rcsum(skb, end - offset); if (err) goto discard_fq; /* Note : skb->rbnode and skb->dev share the same location. */ dev = skb->dev; /* Makes sure compiler wont do silly aliasing games */ barrier(); prev_tail = fq->q.fragments_tail; err = inet_frag_queue_insert(&fq->q, skb, offset, end); if (err) goto insert_error; if (dev) fq->iif = dev->ifindex; fq->q.stamp = skb->tstamp; fq->q.meat += skb->len; fq->ecn |= ecn; add_frag_mem_limit(fq->q.net, skb->truesize); fragsize = -skb_network_offset(skb) + skb->len; if (fragsize > fq->q.max_size) fq->q.max_size = fragsize; /* The first fragment. * nhoffset is obtained from the first fragment, of course. */ if (offset == 0) { fq->nhoffset = nhoff; fq->q.flags |= INET_FRAG_FIRST_IN; } if (fq->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) && fq->q.meat == fq->q.len) { unsigned long orefdst = skb->_skb_refdst; skb->_skb_refdst = 0UL; err = ip6_frag_reasm(fq, skb, prev_tail, dev); skb->_skb_refdst = orefdst; return err; } skb_dst_drop(skb); return -EINPROGRESS; insert_error: if (err == IPFRAG_DUP) { kfree_skb(skb); return -EINVAL; } err = -EINVAL; __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASM_OVERLAPS); discard_fq: inet_frag_kill(&fq->q); __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS); err: kfree_skb(skb); return err; }
static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, netdev_features_t features, struct sk_buff *(*gso_inner_segment)(struct sk_buff *skb, netdev_features_t features), __be16 new_protocol, bool is_ipv6) { int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb); bool remcsum, need_csum, offload_csum, gso_partial; struct sk_buff *segs = ERR_PTR(-EINVAL); struct udphdr *uh = udp_hdr(skb); u16 mac_offset = skb->mac_header; __be16 protocol = skb->protocol; u16 mac_len = skb->mac_len; int udp_offset, outer_hlen; __wsum partial; bool need_ipsec; if (unlikely(!pskb_may_pull(skb, tnl_hlen))) goto out; /* Adjust partial header checksum to negate old length. * We cannot rely on the value contained in uh->len as it is * possible that the actual value exceeds the boundaries of the * 16 bit length field due to the header being added outside of an * IP or IPv6 frame that was already limited to 64K - 1. */ if (skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) partial = (__force __wsum)uh->len; else partial = (__force __wsum)htonl(skb->len); partial = csum_sub(csum_unfold(uh->check), partial); /* setup inner skb. */ skb->encapsulation = 0; SKB_GSO_CB(skb)->encap_level = 0; __skb_pull(skb, tnl_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, skb_inner_network_offset(skb)); skb->mac_len = skb_inner_network_offset(skb); skb->protocol = new_protocol; need_csum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM); skb->encap_hdr_csum = need_csum; remcsum = !!(skb_shinfo(skb)->gso_type & SKB_GSO_TUNNEL_REMCSUM); skb->remcsum_offload = remcsum; need_ipsec = skb_dst(skb) && dst_xfrm(skb_dst(skb)); /* Try to offload checksum if possible */ offload_csum = !!(need_csum && !need_ipsec && (skb->dev->features & (is_ipv6 ? (NETIF_F_HW_CSUM | NETIF_F_IPV6_CSUM) : (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM)))); features &= skb->dev->hw_enc_features; /* The only checksum offload we care about from here on out is the * outer one so strip the existing checksum feature flags and * instead set the flag based on our outer checksum offload value. */ if (remcsum) { features &= ~NETIF_F_CSUM_MASK; if (!need_csum || offload_csum) features |= NETIF_F_HW_CSUM; } /* segment inner packet. */ segs = gso_inner_segment(skb, features); if (IS_ERR_OR_NULL(segs)) { skb_gso_error_unwind(skb, protocol, tnl_hlen, mac_offset, mac_len); goto out; } gso_partial = !!(skb_shinfo(segs)->gso_type & SKB_GSO_PARTIAL); outer_hlen = skb_tnl_header_len(skb); udp_offset = outer_hlen - tnl_hlen; skb = segs; do { unsigned int len; if (remcsum) skb->ip_summed = CHECKSUM_NONE; /* Set up inner headers if we are offloading inner checksum */ if (skb->ip_summed == CHECKSUM_PARTIAL) { skb_reset_inner_headers(skb); skb->encapsulation = 1; } skb->mac_len = mac_len; skb->protocol = protocol; __skb_push(skb, outer_hlen); skb_reset_mac_header(skb); skb_set_network_header(skb, mac_len); skb_set_transport_header(skb, udp_offset); len = skb->len - udp_offset; uh = udp_hdr(skb); /* If we are only performing partial GSO the inner header * will be using a length value equal to only one MSS sized * segment instead of the entire frame. */ if (gso_partial && skb_is_gso(skb)) { uh->len = htons(skb_shinfo(skb)->gso_size + SKB_GSO_CB(skb)->data_offset + skb->head - (unsigned char *)uh); } else { uh->len = htons(len); } if (!need_csum) continue; uh->check = ~csum_fold(csum_add(partial, (__force __wsum)htonl(len))); if (skb->encapsulation || !offload_csum) { uh->check = gso_make_checksum(skb, ~uh->check); if (uh->check == 0) uh->check = CSUM_MANGLED_0; } else { skb->ip_summed = CHECKSUM_PARTIAL; skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct udphdr, check); } } while ((skb = skb->next)); out: return segs; }