From b05229f442288210f2b1f5b4b2a9d71836e90686 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Fri, 29 Apr 2016 17:12:21 -0700 Subject: [PATCH] gre6: Cleanup GREv6 transmit path, call common GRE functions Changes in GREv6 transmit path: - Call gre_checksum, remove gre6_checksum - Rename ip6gre_xmit2 to __gre6_xmit - Call gre_build_header utility function - Call ip6_tnl_xmit common function - Call ip6_tnl_change_mtu, eliminate ip6gre_tunnel_change_mtu Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- net/ipv6/ip6_gre.c | 252 +++++++++++------------------------------------------ 1 file changed, 50 insertions(+), 202 deletions(-) diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 9b33745..1012774 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -488,199 +488,40 @@ struct ipv6_tel_txoption { __u8 dst_opt[8]; }; -static void init_tel_txopt(struct ipv6_tel_txoption *opt, __u8 encap_limit) +static int gre_handle_offloads(struct sk_buff *skb, bool csum) { - memset(opt, 0, sizeof(struct ipv6_tel_txoption)); - - opt->dst_opt[2] = IPV6_TLV_TNL_ENCAP_LIMIT; - opt->dst_opt[3] = 1; - opt->dst_opt[4] = encap_limit; - opt->dst_opt[5] = IPV6_TLV_PADN; - opt->dst_opt[6] = 1; - - opt->ops.dst0opt = (struct ipv6_opt_hdr *) opt->dst_opt; - opt->ops.opt_nflen = 8; + return iptunnel_handle_offloads(skb, + csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); } -static __sum16 gre6_checksum(struct sk_buff *skb) -{ - __wsum csum; - - if (skb->ip_summed == CHECKSUM_PARTIAL) - csum = lco_csum(skb); - else - csum = skb_checksum(skb, sizeof(struct ipv6hdr), - skb->len - sizeof(struct ipv6hdr), 0); - return csum_fold(csum); -} - -static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb, - struct net_device *dev, - __u8 dsfield, - struct flowi6 *fl6, - int encap_limit, - __u32 *pmtu) +static netdev_tx_t __gre6_xmit(struct sk_buff *skb, + struct net_device *dev, __u8 dsfield, + struct flowi6 *fl6, int encap_limit, + __u32 *pmtu, __be16 proto) { struct ip6_tnl *tunnel = netdev_priv(dev); - struct net *net = tunnel->net; - struct net_device *tdev; /* Device to other host */ - struct ipv6hdr *ipv6h; /* Our new IP header */ - unsigned int min_headroom = 0; /* The extra header space needed */ - int gre_hlen; - struct ipv6_tel_txoption opt; - int mtu; - struct dst_entry *dst = NULL, *ndst = NULL; - struct net_device_stats *stats = &tunnel->dev->stats; - int err = -1; - u8 proto; - __be16 protocol; + __be16 protocol = (dev->type == ARPHRD_ETHER) ? + htons(ETH_P_TEB) : proto; if (dev->type == ARPHRD_ETHER) IPCB(skb)->flags = 0; - if (dev->header_ops && dev->type == ARPHRD_IP6GRE) { - gre_hlen = 0; - ipv6h = (struct ipv6hdr *)skb->data; - fl6->daddr = ipv6h->daddr; - } else { - gre_hlen = tunnel->hlen; + if (dev->header_ops && dev->type == ARPHRD_IP6GRE) + fl6->daddr = ((struct ipv6hdr *)skb->data)->daddr; + else fl6->daddr = tunnel->parms.raddr; - } - - if (!fl6->flowi6_mark) - dst = dst_cache_get(&tunnel->dst_cache); - - if (!dst) { - dst = ip6_route_output(net, NULL, fl6); - - if (dst->error) - goto tx_err_link_failure; - dst = xfrm_lookup(net, dst, flowi6_to_flowi(fl6), NULL, 0); - if (IS_ERR(dst)) { - err = PTR_ERR(dst); - dst = NULL; - goto tx_err_link_failure; - } - ndst = dst; - } - - tdev = dst->dev; - - if (tdev == dev) { - stats->collisions++; - net_warn_ratelimited("%s: Local routing loop detected!\n", - tunnel->parms.name); - goto tx_err_dst_release; - } - mtu = dst_mtu(dst) - sizeof(*ipv6h); - if (encap_limit >= 0) { - min_headroom += 8; - mtu -= 8; - } - if (mtu < IPV6_MIN_MTU) - mtu = IPV6_MIN_MTU; - if (skb_dst(skb)) - skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); - if (skb->len > mtu && !skb_is_gso(skb)) { - *pmtu = mtu; - err = -EMSGSIZE; - goto tx_err_dst_release; - } + if (tunnel->parms.o_flags & TUNNEL_SEQ) + tunnel->o_seqno++; - if (tunnel->err_count > 0) { - if (time_before(jiffies, - tunnel->err_time + IP6TUNNEL_ERR_TIMEO)) { - tunnel->err_count--; + /* Push GRE header. */ + gre_build_header(skb, tunnel->tun_hlen, tunnel->parms.o_flags, + protocol, tunnel->parms.o_key, htonl(tunnel->o_seqno)); - dst_link_failure(skb); - } else - tunnel->err_count = 0; - } + skb_set_inner_protocol(skb, proto); - skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); - - min_headroom += LL_RESERVED_SPACE(tdev) + gre_hlen + dst->header_len; - - if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) { - int head_delta = SKB_DATA_ALIGN(min_headroom - - skb_headroom(skb) + - 16); - - err = pskb_expand_head(skb, max_t(int, head_delta, 0), - 0, GFP_ATOMIC); - if (min_headroom > dev->needed_headroom) - dev->needed_headroom = min_headroom; - if (unlikely(err)) - goto tx_err_dst_release; - } - - if (!fl6->flowi6_mark && ndst) - dst_cache_set_ip6(&tunnel->dst_cache, ndst, &fl6->saddr); - skb_dst_set(skb, dst); - - proto = NEXTHDR_GRE; - if (encap_limit >= 0) { - init_tel_txopt(&opt, encap_limit); - ipv6_push_nfrag_opts(skb, &opt.ops, &proto, NULL); - } - - err = iptunnel_handle_offloads(skb, - (tunnel->parms.o_flags & GRE_CSUM) ? - SKB_GSO_GRE_CSUM : SKB_GSO_GRE); - if (err) - goto tx_err_dst_release; - - skb_push(skb, gre_hlen); - skb_reset_network_header(skb); - skb_set_transport_header(skb, sizeof(*ipv6h)); - - /* - * Push down and install the IP header. - */ - ipv6h = ipv6_hdr(skb); - ip6_flow_hdr(ipv6h, INET_ECN_encapsulate(0, dsfield), - ip6_make_flowlabel(net, skb, fl6->flowlabel, true, fl6)); - ipv6h->hop_limit = tunnel->parms.hop_limit; - ipv6h->nexthdr = proto; - ipv6h->saddr = fl6->saddr; - ipv6h->daddr = fl6->daddr; - - ((__be16 *)(ipv6h + 1))[0] = tunnel->parms.o_flags; - protocol = (dev->type == ARPHRD_ETHER) ? - htons(ETH_P_TEB) : skb->protocol; - ((__be16 *)(ipv6h + 1))[1] = protocol; - - if (tunnel->parms.o_flags&(GRE_KEY|GRE_CSUM|GRE_SEQ)) { - __be32 *ptr = (__be32 *)(((u8 *)ipv6h) + tunnel->hlen - 4); - - if (tunnel->parms.o_flags&GRE_SEQ) { - ++tunnel->o_seqno; - *ptr = htonl(tunnel->o_seqno); - ptr--; - } - if (tunnel->parms.o_flags&GRE_KEY) { - *ptr = tunnel->parms.o_key; - ptr--; - } - if ((tunnel->parms.o_flags & GRE_CSUM) && - !(skb_shinfo(skb)->gso_type & - (SKB_GSO_GRE | SKB_GSO_GRE_CSUM))) { - *ptr = 0; - *(__sum16 *)ptr = gre6_checksum(skb); - } - } - - skb_set_inner_protocol(skb, protocol); - - ip6tunnel_xmit(NULL, skb, dev); - return 0; -tx_err_link_failure: - stats->tx_carrier_errors++; - dst_link_failure(skb); -tx_err_dst_release: - dst_release(dst); - return err; + return ip6_tnl_xmit(skb, dev, dsfield, fl6, encap_limit, pmtu, + NEXTHDR_GRE); } static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) @@ -699,7 +540,6 @@ static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) encap_limit = t->parms.encap_limit; memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); - fl6.flowi6_proto = IPPROTO_GRE; dsfield = ipv4_get_dsfield(iph); @@ -709,7 +549,12 @@ static inline int ip6gre_xmit_ipv4(struct sk_buff *skb, struct net_device *dev) if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) fl6.flowi6_mark = skb->mark; - err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); + err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); + if (err) + return -1; + + err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, &mtu, + skb->protocol); if (err != 0) { /* XXX: send ICMP error even if DF is not set. */ if (err == -EMSGSIZE) @@ -749,7 +594,6 @@ static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) encap_limit = t->parms.encap_limit; memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); - fl6.flowi6_proto = IPPROTO_GRE; dsfield = ipv6_get_dsfield(ipv6h); if (t->parms.flags & IP6_TNL_F_USE_ORIG_TCLASS) @@ -759,7 +603,11 @@ static inline int ip6gre_xmit_ipv6(struct sk_buff *skb, struct net_device *dev) if (t->parms.flags & IP6_TNL_F_USE_ORIG_FWMARK) fl6.flowi6_mark = skb->mark; - err = ip6gre_xmit2(skb, dev, dsfield, &fl6, encap_limit, &mtu); + if (gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM))) + return -1; + + err = __gre6_xmit(skb, dev, dsfield, &fl6, encap_limit, + &mtu, skb->protocol); if (err != 0) { if (err == -EMSGSIZE) icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); @@ -803,7 +651,11 @@ static int ip6gre_xmit_other(struct sk_buff *skb, struct net_device *dev) memcpy(&fl6, &t->fl.u.ip6, sizeof(fl6)); fl6.flowi6_proto = skb->protocol; - err = ip6gre_xmit2(skb, dev, 0, &fl6, encap_limit, &mtu); + err = gre_handle_offloads(skb, !!(t->parms.o_flags & TUNNEL_CSUM)); + if (err) + return err; + + err = __gre6_xmit(skb, dev, 0, &fl6, encap_limit, &mtu, skb->protocol); return err; } @@ -1080,15 +932,6 @@ done: return err; } -static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu) -{ - if (new_mtu < 68 || - new_mtu > 0xFFF8 - dev->hard_header_len) - return -EINVAL; - dev->mtu = new_mtu; - return 0; -} - static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) @@ -1132,7 +975,7 @@ static const struct net_device_ops ip6gre_netdev_ops = { .ndo_uninit = ip6gre_tunnel_uninit, .ndo_start_xmit = ip6gre_tunnel_xmit, .ndo_do_ioctl = ip6gre_tunnel_ioctl, - .ndo_change_mtu = ip6gre_tunnel_change_mtu, + .ndo_change_mtu = ip6_tnl_change_mtu, .ndo_get_stats64 = ip_tunnel_get_stats64, .ndo_get_iflink = ip6_tnl_get_iflink, }; @@ -1148,17 +991,11 @@ static void ip6gre_dev_free(struct net_device *dev) static void ip6gre_tunnel_setup(struct net_device *dev) { - struct ip6_tnl *t; - dev->netdev_ops = &ip6gre_netdev_ops; dev->destructor = ip6gre_dev_free; dev->type = ARPHRD_IP6GRE; - dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr) + 4; - dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr) - 4; - t = netdev_priv(dev); - if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) - dev->mtu -= 8; + dev->flags |= IFF_NOARP; dev->addr_len = sizeof(struct in6_addr); netif_keep_dst(dev); @@ -1168,6 +1005,7 @@ static int ip6gre_tunnel_init_common(struct net_device *dev) { struct ip6_tnl *tunnel; int ret; + int t_hlen; tunnel = netdev_priv(dev); @@ -1186,6 +1024,16 @@ static int ip6gre_tunnel_init_common(struct net_device *dev) return ret; } + tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); + + t_hlen = tunnel->hlen + sizeof(struct ipv6hdr); + + dev->needed_headroom = LL_MAX_HEADER + t_hlen + 4; + dev->mtu = ETH_DATA_LEN - t_hlen - 4; + + if (!(tunnel->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) + dev->mtu -= 8; + return 0; } @@ -1420,7 +1268,7 @@ static const struct net_device_ops ip6gre_tap_netdev_ops = { .ndo_start_xmit = ip6gre_tunnel_xmit, .ndo_set_mac_address = eth_mac_addr, .ndo_validate_addr = eth_validate_addr, - .ndo_change_mtu = ip6gre_tunnel_change_mtu, + .ndo_change_mtu = ip6_tnl_change_mtu, .ndo_get_stats64 = ip_tunnel_get_stats64, .ndo_get_iflink = ip6_tnl_get_iflink, }; -- 2.7.4