From 731362674580cb0c696cd1b1a03d8461a10cf90a Mon Sep 17 00:00:00 2001 From: Pravin B Shelar Date: Thu, 7 Mar 2013 13:21:51 +0000 Subject: [PATCH] tunneling: Add generic Tunnel segmentation. Adds generic tunneling offloading support for IPv4-UDP based tunnels. GSO type is added to request this offload for a skb. netdev feature NETIF_F_UDP_TUNNEL is added for hardware offloaded udp-tunnel support. Currently no device supports this feature, software offload is used. This can be used by tunneling protocols like VXLAN. CC: Jesse Gross Signed-off-by: Pravin B Shelar Acked-by: Stephen Hemminger Signed-off-by: David S. Miller --- include/linux/netdev_features.h | 7 +-- include/linux/skbuff.h | 2 + net/core/ethtool.c | 1 + net/ipv4/af_inet.c | 6 ++- net/ipv4/tcp.c | 1 + net/ipv4/udp.c | 115 +++++++++++++++++++++++++++++++--------- net/ipv6/ip6_offload.c | 1 + net/ipv6/udp_offload.c | 8 ++- 8 files changed, 111 insertions(+), 30 deletions(-) diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h index 3dd3934..f5e797c 100644 --- a/include/linux/netdev_features.h +++ b/include/linux/netdev_features.h @@ -42,9 +42,9 @@ enum { NETIF_F_TSO6_BIT, /* ... TCPv6 segmentation */ NETIF_F_FSO_BIT, /* ... FCoE segmentation */ NETIF_F_GSO_GRE_BIT, /* ... GRE with TSO */ - /**/NETIF_F_GSO_LAST, /* [can't be last bit, see GSO_MASK] */ - NETIF_F_GSO_RESERVED2 /* ... free (fill GSO_MASK to 8 bits) */ - = NETIF_F_GSO_LAST, + NETIF_F_GSO_UDP_TUNNEL_BIT, /* ... UDP TUNNEL with TSO */ + /**/NETIF_F_GSO_LAST = /* last bit, see GSO_MASK */ + NETIF_F_GSO_UDP_TUNNEL_BIT, NETIF_F_FCOE_CRC_BIT, /* FCoE CRC32 */ NETIF_F_SCTP_CSUM_BIT, /* SCTP checksum offload */ @@ -103,6 +103,7 @@ enum { #define NETIF_F_RXFCS __NETIF_F(RXFCS) #define NETIF_F_RXALL __NETIF_F(RXALL) #define NETIF_F_GRE_GSO __NETIF_F(GSO_GRE) +#define NETIF_F_UDP_TUNNEL __NETIF_F(UDP_TUNNEL) /* Features valid for ethtool to change */ /* = all defined minus driver/device-class-related */ diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index d7f96ff..eb2106f 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -316,6 +316,8 @@ enum { SKB_GSO_FCOE = 1 << 5, SKB_GSO_GRE = 1 << 6, + + SKB_GSO_UDP_TUNNEL = 1 << 7, }; #if BITS_PER_LONG > 32 diff --git a/net/core/ethtool.c b/net/core/ethtool.c index 3e9b2c3..adc1351 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -78,6 +78,7 @@ static const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] [NETIF_F_TSO6_BIT] = "tx-tcp6-segmentation", [NETIF_F_FSO_BIT] = "tx-fcoe-segmentation", [NETIF_F_GSO_GRE_BIT] = "tx-gre-segmentation", + [NETIF_F_GSO_UDP_TUNNEL_BIT] = "tx-udp_tnl-segmentation", [NETIF_F_FCOE_CRC_BIT] = "tx-checksum-fcoe-crc", [NETIF_F_SCTP_CSUM_BIT] = "tx-checksum-sctp", diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index dc3f677..9e5882c 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -1283,6 +1283,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, int ihl; int id; unsigned int offset = 0; + bool tunnel; if (unlikely(skb_shinfo(skb)->gso_type & ~(SKB_GSO_TCPV4 | @@ -1290,6 +1291,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, SKB_GSO_DODGY | SKB_GSO_TCP_ECN | SKB_GSO_GRE | + SKB_GSO_UDP_TUNNEL | 0))) goto out; @@ -1304,6 +1306,8 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, if (unlikely(!pskb_may_pull(skb, ihl))) goto out; + tunnel = !!skb->encapsulation; + __skb_pull(skb, ihl); skb_reset_transport_header(skb); iph = ip_hdr(skb); @@ -1323,7 +1327,7 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb, skb = segs; do { iph = ip_hdr(skb); - if (proto == IPPROTO_UDP) { + if (!tunnel && proto == IPPROTO_UDP) { iph->id = htons(id); iph->frag_off = htons(offset >> 3); if (skb->next != NULL) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 47e854f..8d14573 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3044,6 +3044,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, SKB_GSO_TCP_ECN | SKB_GSO_TCPV6 | SKB_GSO_GRE | + SKB_GSO_UDP_TUNNEL | 0) || !(type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))) goto out; diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 265c42c..41760e0 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -2272,31 +2272,88 @@ void __init udp_init(void) int udp4_ufo_send_check(struct sk_buff *skb) { - const struct iphdr *iph; - struct udphdr *uh; - - if (!pskb_may_pull(skb, sizeof(*uh))) + if (!pskb_may_pull(skb, sizeof(struct udphdr))) return -EINVAL; - iph = ip_hdr(skb); - uh = udp_hdr(skb); + if (likely(!skb->encapsulation)) { + const struct iphdr *iph; + struct udphdr *uh; - uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len, - IPPROTO_UDP, 0); - skb->csum_start = skb_transport_header(skb) - skb->head; - skb->csum_offset = offsetof(struct udphdr, check); - skb->ip_summed = CHECKSUM_PARTIAL; + iph = ip_hdr(skb); + uh = udp_hdr(skb); + + uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, skb->len, + IPPROTO_UDP, 0); + skb->csum_start = skb_transport_header(skb) - skb->head; + skb->csum_offset = offsetof(struct udphdr, check); + skb->ip_summed = CHECKSUM_PARTIAL; + } return 0; } +static struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb, + netdev_features_t features) +{ + struct sk_buff *segs = ERR_PTR(-EINVAL); + int mac_len = skb->mac_len; + int tnl_hlen = skb_inner_mac_header(skb) - skb_transport_header(skb); + int outer_hlen; + netdev_features_t enc_features; + + if (unlikely(!pskb_may_pull(skb, tnl_hlen))) + goto out; + + skb->encapsulation = 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); + + /* segment inner packet. */ + enc_features = skb->dev->hw_enc_features & netif_skb_features(skb); + segs = skb_mac_gso_segment(skb, enc_features); + if (!segs || IS_ERR(segs)) + goto out; + + outer_hlen = skb_tnl_header_len(skb); + skb = segs; + do { + struct udphdr *uh; + int udp_offset = outer_hlen - tnl_hlen; + + skb->mac_len = mac_len; + + skb_push(skb, outer_hlen); + skb_reset_mac_header(skb); + skb_set_network_header(skb, mac_len); + skb_set_transport_header(skb, udp_offset); + uh = udp_hdr(skb); + uh->len = htons(skb->len - udp_offset); + + /* csum segment if tunnel sets skb with csum. */ + if (unlikely(uh->check)) { + struct iphdr *iph = ip_hdr(skb); + + uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, + skb->len - udp_offset, + IPPROTO_UDP, 0); + uh->check = csum_fold(skb_checksum(skb, udp_offset, + skb->len - udp_offset, 0)); + if (uh->check == 0) + uh->check = CSUM_MANGLED_0; + + } + skb->ip_summed = CHECKSUM_NONE; + } while ((skb = skb->next)); +out: + return segs; +} + struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, netdev_features_t features) { struct sk_buff *segs = ERR_PTR(-EINVAL); unsigned int mss; - int offset; - __wsum csum; - mss = skb_shinfo(skb)->gso_size; if (unlikely(skb->len <= mss)) goto out; @@ -2306,6 +2363,7 @@ struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, int type = skb_shinfo(skb)->gso_type; if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY | + SKB_GSO_UDP_TUNNEL | SKB_GSO_GRE) || !(type & (SKB_GSO_UDP)))) goto out; @@ -2316,20 +2374,27 @@ struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb, goto out; } - /* Do software UFO. Complete and fill in the UDP checksum as HW cannot - * do checksum of UDP packets sent as multiple IP fragments. - */ - offset = skb_checksum_start_offset(skb); - csum = skb_checksum(skb, offset, skb->len - offset, 0); - offset += skb->csum_offset; - *(__sum16 *)(skb->data + offset) = csum_fold(csum); - skb->ip_summed = CHECKSUM_NONE; - /* Fragment the skb. IP headers of the fragments are updated in * inet_gso_segment() */ - segs = skb_segment(skb, features); + if (skb->encapsulation && skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL) + segs = skb_udp_tunnel_segment(skb, features); + else { + int offset; + __wsum csum; + + /* Do software UFO. Complete and fill in the UDP checksum as + * HW cannot do checksum of UDP packets sent as multiple + * IP fragments. + */ + offset = skb_checksum_start_offset(skb); + csum = skb_checksum(skb, offset, skb->len - offset, 0); + offset += skb->csum_offset; + *(__sum16 *)(skb->data + offset) = csum_fold(csum); + skb->ip_summed = CHECKSUM_NONE; + + segs = skb_segment(skb, features); + } out: return segs; } - diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index 7a0d25a..71b766e 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -97,6 +97,7 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, SKB_GSO_DODGY | SKB_GSO_TCP_ECN | SKB_GSO_GRE | + SKB_GSO_UDP_TUNNEL | SKB_GSO_TCPV6 | 0))) goto out; diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index cf05cf0..3bb3a89 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -21,6 +21,10 @@ static int udp6_ufo_send_check(struct sk_buff *skb) const struct ipv6hdr *ipv6h; struct udphdr *uh; + /* UDP Tunnel offload on ipv6 is not yet supported. */ + if (skb->encapsulation) + return -EINVAL; + if (!pskb_may_pull(skb, sizeof(*uh))) return -EINVAL; @@ -56,7 +60,9 @@ static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, /* Packet is from an untrusted source, reset gso_segs. */ int type = skb_shinfo(skb)->gso_type; - if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY | + if (unlikely(type & ~(SKB_GSO_UDP | + SKB_GSO_DODGY | + SKB_GSO_UDP_TUNNEL | SKB_GSO_GRE) || !(type & (SKB_GSO_UDP)))) goto out; -- 2.7.4