Commit | Line | Data |
---|---|---|
5edbb07d VY |
1 | /* |
2 | * IPV6 GSO/GRO offload support | |
3 | * Linux INET6 implementation | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or | |
6 | * modify it under the terms of the GNU General Public License | |
7 | * as published by the Free Software Foundation; either version | |
8 | * 2 of the License, or (at your option) any later version. | |
9 | * | |
10 | * UDPv6 GSO support | |
11 | */ | |
12 | #include <linux/skbuff.h> | |
57c67ff4 | 13 | #include <linux/netdevice.h> |
5edbb07d VY |
14 | #include <net/protocol.h> |
15 | #include <net/ipv6.h> | |
16 | #include <net/udp.h> | |
d4d0d355 | 17 | #include <net/ip6_checksum.h> |
5edbb07d VY |
18 | #include "ip6_offload.h" |
19 | ||
5edbb07d | 20 | static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, |
d949d826 | 21 | netdev_features_t features) |
5edbb07d VY |
22 | { |
23 | struct sk_buff *segs = ERR_PTR(-EINVAL); | |
24 | unsigned int mss; | |
25 | unsigned int unfrag_ip6hlen, unfrag_len; | |
26 | struct frag_hdr *fptr; | |
1e2bd517 | 27 | u8 *packet_start, *prevhdr; |
5edbb07d VY |
28 | u8 nexthdr; |
29 | u8 frag_hdr_sz = sizeof(struct frag_hdr); | |
5edbb07d | 30 | __wsum csum; |
1e2bd517 | 31 | int tnl_hlen; |
5edbb07d VY |
32 | |
33 | mss = skb_shinfo(skb)->gso_size; | |
34 | if (unlikely(skb->len <= mss)) | |
35 | goto out; | |
36 | ||
37 | if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) { | |
38 | /* Packet is from an untrusted source, reset gso_segs. */ | |
39 | int type = skb_shinfo(skb)->gso_type; | |
40 | ||
73136267 PS |
41 | if (unlikely(type & ~(SKB_GSO_UDP | |
42 | SKB_GSO_DODGY | | |
43 | SKB_GSO_UDP_TUNNEL | | |
0f4f4ffa | 44 | SKB_GSO_UDP_TUNNEL_CSUM | |
e585f236 | 45 | SKB_GSO_TUNNEL_REMCSUM | |
0d89d203 | 46 | SKB_GSO_GRE | |
4749c09c | 47 | SKB_GSO_GRE_CSUM | |
cb32f511 | 48 | SKB_GSO_IPIP | |
59b93b41 | 49 | SKB_GSO_SIT) || |
5edbb07d VY |
50 | !(type & (SKB_GSO_UDP)))) |
51 | goto out; | |
52 | ||
53 | skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss); | |
54 | ||
0508c07f VY |
55 | /* Set the IPv6 fragment id if not set yet */ |
56 | if (!skb_shinfo(skb)->ip6_frag_id) | |
5a352dd0 | 57 | ipv6_proxy_select_ident(dev_net(skb->dev), skb); |
0508c07f | 58 | |
5edbb07d VY |
59 | segs = NULL; |
60 | goto out; | |
61 | } | |
62 | ||
0f4f4ffa TH |
63 | if (skb->encapsulation && skb_shinfo(skb)->gso_type & |
64 | (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM)) | |
8bce6d7d | 65 | segs = skb_udp_tunnel_segment(skb, features, true); |
d949d826 | 66 | else { |
f71470b3 TH |
67 | const struct ipv6hdr *ipv6h; |
68 | struct udphdr *uh; | |
69 | ||
70 | if (!pskb_may_pull(skb, sizeof(struct udphdr))) | |
71 | goto out; | |
72 | ||
d949d826 CW |
73 | /* Do software UFO. Complete and fill in the UDP checksum as HW cannot |
74 | * do checksum of UDP packets sent as multiple IP fragments. | |
75 | */ | |
f71470b3 TH |
76 | |
77 | uh = udp_hdr(skb); | |
78 | ipv6h = ipv6_hdr(skb); | |
79 | ||
80 | uh->check = 0; | |
81 | csum = skb_checksum(skb, 0, skb->len, 0); | |
82 | uh->check = udp_v6_check(skb->len, &ipv6h->saddr, | |
83 | &ipv6h->daddr, csum); | |
f71470b3 TH |
84 | if (uh->check == 0) |
85 | uh->check = CSUM_MANGLED_0; | |
86 | ||
d949d826 CW |
87 | skb->ip_summed = CHECKSUM_NONE; |
88 | ||
22463876 AD |
89 | /* If there is no outer header we can fake a checksum offload |
90 | * due to the fact that we have already done the checksum in | |
91 | * software prior to segmenting the frame. | |
92 | */ | |
93 | if (!skb->encap_hdr_csum) | |
94 | features |= NETIF_F_HW_CSUM; | |
95 | ||
d949d826 CW |
96 | /* Check if there is enough headroom to insert fragment header. */ |
97 | tnl_hlen = skb_tnl_header_len(skb); | |
0e033e04 | 98 | if (skb->mac_header < (tnl_hlen + frag_hdr_sz)) { |
d949d826 CW |
99 | if (gso_pskb_expand_head(skb, tnl_hlen + frag_hdr_sz)) |
100 | goto out; | |
101 | } | |
102 | ||
103 | /* Find the unfragmentable header and shift it left by frag_hdr_sz | |
104 | * bytes to insert fragment header. | |
105 | */ | |
106 | unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr); | |
107 | nexthdr = *prevhdr; | |
108 | *prevhdr = NEXTHDR_FRAGMENT; | |
109 | unfrag_len = (skb_network_header(skb) - skb_mac_header(skb)) + | |
110 | unfrag_ip6hlen + tnl_hlen; | |
111 | packet_start = (u8 *) skb->head + SKB_GSO_CB(skb)->mac_offset; | |
112 | memmove(packet_start-frag_hdr_sz, packet_start, unfrag_len); | |
113 | ||
114 | SKB_GSO_CB(skb)->mac_offset -= frag_hdr_sz; | |
115 | skb->mac_header -= frag_hdr_sz; | |
116 | skb->network_header -= frag_hdr_sz; | |
117 | ||
118 | fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen); | |
119 | fptr->nexthdr = nexthdr; | |
120 | fptr->reserved = 0; | |
8e199dfd | 121 | if (!skb_shinfo(skb)->ip6_frag_id) |
5a352dd0 | 122 | ipv6_proxy_select_ident(dev_net(skb->dev), skb); |
8e199dfd | 123 | fptr->identification = skb_shinfo(skb)->ip6_frag_id; |
d949d826 CW |
124 | |
125 | /* Fragment the skb. ipv6 header and the remaining fields of the | |
126 | * fragment header are updated in ipv6_gso_segment() | |
127 | */ | |
128 | segs = skb_segment(skb, features); | |
1e2bd517 | 129 | } |
5edbb07d | 130 | |
5edbb07d VY |
131 | out: |
132 | return segs; | |
133 | } | |
57c67ff4 TH |
134 | |
135 | static struct sk_buff **udp6_gro_receive(struct sk_buff **head, | |
136 | struct sk_buff *skb) | |
137 | { | |
138 | struct udphdr *uh = udp_gro_udphdr(skb); | |
139 | ||
2abb7cdc TH |
140 | if (unlikely(!uh)) |
141 | goto flush; | |
142 | ||
57c67ff4 | 143 | /* Don't bother verifying checksum if we're going to flush anyway. */ |
2d8f7e2c | 144 | if (NAPI_GRO_CB(skb)->flush) |
2abb7cdc | 145 | goto skip; |
57c67ff4 | 146 | |
2abb7cdc TH |
147 | if (skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, |
148 | ip6_gro_compute_pseudo)) | |
149 | goto flush; | |
150 | else if (uh->check) | |
151 | skb_gro_checksum_try_convert(skb, IPPROTO_UDP, uh->check, | |
152 | ip6_gro_compute_pseudo); | |
153 | ||
154 | skip: | |
efc98d08 | 155 | NAPI_GRO_CB(skb)->is_ipv6 = 1; |
57c67ff4 | 156 | return udp_gro_receive(head, skb, uh); |
2abb7cdc TH |
157 | |
158 | flush: | |
159 | NAPI_GRO_CB(skb)->flush = 1; | |
160 | return NULL; | |
57c67ff4 TH |
161 | } |
162 | ||
cc9c668a | 163 | static int udp6_gro_complete(struct sk_buff *skb, int nhoff) |
57c67ff4 TH |
164 | { |
165 | const struct ipv6hdr *ipv6h = ipv6_hdr(skb); | |
166 | struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); | |
167 | ||
6db93ea1 TH |
168 | if (uh->check) { |
169 | skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM; | |
57c67ff4 TH |
170 | uh->check = ~udp_v6_check(skb->len - nhoff, &ipv6h->saddr, |
171 | &ipv6h->daddr, 0); | |
6db93ea1 TH |
172 | } else { |
173 | skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL; | |
174 | } | |
57c67ff4 TH |
175 | |
176 | return udp_gro_complete(skb, nhoff); | |
177 | } | |
178 | ||
5edbb07d | 179 | static const struct net_offload udpv6_offload = { |
f191a1d1 | 180 | .callbacks = { |
f191a1d1 | 181 | .gso_segment = udp6_ufo_fragment, |
57c67ff4 TH |
182 | .gro_receive = udp6_gro_receive, |
183 | .gro_complete = udp6_gro_complete, | |
f191a1d1 | 184 | }, |
5edbb07d VY |
185 | }; |
186 | ||
187 | int __init udp_offload_init(void) | |
188 | { | |
189 | return inet6_add_offload(&udpv6_offload, IPPROTO_UDP); | |
190 | } |