~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/net/ipv6/ip6_offload.c

Version: ~ [ linux-5.19-rc3 ] ~ [ linux-5.18.5 ] ~ [ linux-5.17.15 ] ~ [ linux-5.16.20 ] ~ [ linux-5.15.48 ] ~ [ linux-5.14.21 ] ~ [ linux-5.13.19 ] ~ [ linux-5.12.19 ] ~ [ linux-5.11.22 ] ~ [ linux-5.10.123 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.199 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.248 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.284 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.319 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.302 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.9 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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 
 11 #include <linux/kernel.h>
 12 #include <linux/socket.h>
 13 #include <linux/netdevice.h>
 14 #include <linux/skbuff.h>
 15 #include <linux/printk.h>
 16 
 17 #include <net/protocol.h>
 18 #include <net/ipv6.h>
 19 
 20 #include "ip6_offload.h"
 21 
 22 static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
 23 {
 24         const struct net_offload *ops = NULL;
 25 
 26         for (;;) {
 27                 struct ipv6_opt_hdr *opth;
 28                 int len;
 29 
 30                 if (proto != NEXTHDR_HOP) {
 31                         ops = rcu_dereference(inet6_offloads[proto]);
 32 
 33                         if (unlikely(!ops))
 34                                 break;
 35 
 36                         if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
 37                                 break;
 38                 }
 39 
 40                 if (unlikely(!pskb_may_pull(skb, 8)))
 41                         break;
 42 
 43                 opth = (void *)skb->data;
 44                 len = ipv6_optlen(opth);
 45 
 46                 if (unlikely(!pskb_may_pull(skb, len)))
 47                         break;
 48 
 49                 opth = (void *)skb->data;
 50                 proto = opth->nexthdr;
 51                 __skb_pull(skb, len);
 52         }
 53 
 54         return proto;
 55 }
 56 
 57 static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
 58         netdev_features_t features)
 59 {
 60         struct sk_buff *segs = ERR_PTR(-EINVAL);
 61         struct ipv6hdr *ipv6h;
 62         const struct net_offload *ops;
 63         int proto;
 64         struct frag_hdr *fptr;
 65         unsigned int unfrag_ip6hlen;
 66         u8 *prevhdr;
 67         int offset = 0;
 68         bool encap, udpfrag;
 69         int nhoff;
 70 
 71         if (unlikely(skb_shinfo(skb)->gso_type &
 72                      ~(SKB_GSO_TCPV4 |
 73                        SKB_GSO_UDP |
 74                        SKB_GSO_DODGY |
 75                        SKB_GSO_TCP_ECN |
 76                        SKB_GSO_GRE |
 77                        SKB_GSO_GRE_CSUM |
 78                        SKB_GSO_IPIP |
 79                        SKB_GSO_SIT |
 80                        SKB_GSO_UDP_TUNNEL |
 81                        SKB_GSO_UDP_TUNNEL_CSUM |
 82                        SKB_GSO_TUNNEL_REMCSUM |
 83                        SKB_GSO_TCPV6 |
 84                        0)))
 85                 goto out;
 86 
 87         skb_reset_network_header(skb);
 88         nhoff = skb_network_header(skb) - skb_mac_header(skb);
 89         if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
 90                 goto out;
 91 
 92         encap = SKB_GSO_CB(skb)->encap_level > 0;
 93         if (encap)
 94                 features &= skb->dev->hw_enc_features;
 95         SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
 96 
 97         ipv6h = ipv6_hdr(skb);
 98         __skb_pull(skb, sizeof(*ipv6h));
 99         segs = ERR_PTR(-EPROTONOSUPPORT);
100 
101         proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
102 
103         if (skb->encapsulation &&
104             skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP))
105                 udpfrag = proto == IPPROTO_UDP && encap;
106         else
107                 udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;
108 
109         ops = rcu_dereference(inet6_offloads[proto]);
110         if (likely(ops && ops->callbacks.gso_segment)) {
111                 skb_reset_transport_header(skb);
112                 segs = ops->callbacks.gso_segment(skb, features);
113         }
114 
115         if (IS_ERR(segs))
116                 goto out;
117 
118         for (skb = segs; skb; skb = skb->next) {
119                 ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
120                 ipv6h->payload_len = htons(skb->len - nhoff - sizeof(*ipv6h));
121                 skb->network_header = (u8 *)ipv6h - skb->head;
122 
123                 if (udpfrag) {
124                         unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
125                         fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen);
126                         fptr->frag_off = htons(offset);
127                         if (skb->next)
128                                 fptr->frag_off |= htons(IP6_MF);
129                         offset += (ntohs(ipv6h->payload_len) -
130                                    sizeof(struct frag_hdr));
131                 }
132                 if (encap)
133                         skb_reset_inner_headers(skb);
134         }
135 
136 out:
137         return segs;
138 }
139 
140 /* Return the total length of all the extension hdrs, following the same
141  * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
142  */
143 static int ipv6_exthdrs_len(struct ipv6hdr *iph,
144                             const struct net_offload **opps)
145 {
146         struct ipv6_opt_hdr *opth = (void *)iph;
147         int len = 0, proto, optlen = sizeof(*iph);
148 
149         proto = iph->nexthdr;
150         for (;;) {
151                 if (proto != NEXTHDR_HOP) {
152                         *opps = rcu_dereference(inet6_offloads[proto]);
153                         if (unlikely(!(*opps)))
154                                 break;
155                         if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
156                                 break;
157                 }
158                 opth = (void *)opth + optlen;
159                 optlen = ipv6_optlen(opth);
160                 len += optlen;
161                 proto = opth->nexthdr;
162         }
163         return len;
164 }
165 
166 static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
167                                          struct sk_buff *skb)
168 {
169         const struct net_offload *ops;
170         struct sk_buff **pp = NULL;
171         struct sk_buff *p;
172         struct ipv6hdr *iph;
173         unsigned int nlen;
174         unsigned int hlen;
175         unsigned int off;
176         u16 flush = 1;
177         int proto;
178 
179         off = skb_gro_offset(skb);
180         hlen = off + sizeof(*iph);
181         iph = skb_gro_header_fast(skb, off);
182         if (skb_gro_header_hard(skb, hlen)) {
183                 iph = skb_gro_header_slow(skb, hlen, off);
184                 if (unlikely(!iph))
185                         goto out;
186         }
187 
188         skb_set_network_header(skb, off);
189         skb_gro_pull(skb, sizeof(*iph));
190         skb_set_transport_header(skb, skb_gro_offset(skb));
191 
192         flush += ntohs(iph->payload_len) != skb_gro_len(skb);
193 
194         rcu_read_lock();
195         proto = iph->nexthdr;
196         ops = rcu_dereference(inet6_offloads[proto]);
197         if (!ops || !ops->callbacks.gro_receive) {
198                 __pskb_pull(skb, skb_gro_offset(skb));
199                 proto = ipv6_gso_pull_exthdrs(skb, proto);
200                 skb_gro_pull(skb, -skb_transport_offset(skb));
201                 skb_reset_transport_header(skb);
202                 __skb_push(skb, skb_gro_offset(skb));
203 
204                 ops = rcu_dereference(inet6_offloads[proto]);
205                 if (!ops || !ops->callbacks.gro_receive)
206                         goto out_unlock;
207 
208                 iph = ipv6_hdr(skb);
209         }
210 
211         NAPI_GRO_CB(skb)->proto = proto;
212 
213         flush--;
214         nlen = skb_network_header_len(skb);
215 
216         for (p = *head; p; p = p->next) {
217                 const struct ipv6hdr *iph2;
218                 __be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
219 
220                 if (!NAPI_GRO_CB(p)->same_flow)
221                         continue;
222 
223                 iph2 = (struct ipv6hdr *)(p->data + off);
224                 first_word = *(__be32 *)iph ^ *(__be32 *)iph2;
225 
226                 /* All fields must match except length and Traffic Class.
227                  * XXX skbs on the gro_list have all been parsed and pulled
228                  * already so we don't need to compare nlen
229                  * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
230                  * memcmp() alone below is suffcient, right?
231                  */
232                  if ((first_word & htonl(0xF00FFFFF)) ||
233                     memcmp(&iph->nexthdr, &iph2->nexthdr,
234                            nlen - offsetof(struct ipv6hdr, nexthdr))) {
235                         NAPI_GRO_CB(p)->same_flow = 0;
236                         continue;
237                 }
238                 /* flush if Traffic Class fields are different */
239                 NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000));
240                 NAPI_GRO_CB(p)->flush |= flush;
241 
242                 /* Clear flush_id, there's really no concept of ID in IPv6. */
243                 NAPI_GRO_CB(p)->flush_id = 0;
244         }
245 
246         NAPI_GRO_CB(skb)->flush |= flush;
247 
248         skb_gro_postpull_rcsum(skb, iph, nlen);
249 
250         pp = ops->callbacks.gro_receive(head, skb);
251 
252 out_unlock:
253         rcu_read_unlock();
254 
255 out:
256         NAPI_GRO_CB(skb)->flush |= flush;
257 
258         return pp;
259 }
260 
261 static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
262 {
263         const struct net_offload *ops;
264         struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff);
265         int err = -ENOSYS;
266 
267         iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));
268 
269         rcu_read_lock();
270 
271         nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
272         if (WARN_ON(!ops || !ops->callbacks.gro_complete))
273                 goto out_unlock;
274 
275         err = ops->callbacks.gro_complete(skb, nhoff);
276 
277 out_unlock:
278         rcu_read_unlock();
279 
280         return err;
281 }
282 
283 static struct packet_offload ipv6_packet_offload __read_mostly = {
284         .type = cpu_to_be16(ETH_P_IPV6),
285         .callbacks = {
286                 .gso_segment = ipv6_gso_segment,
287                 .gro_receive = ipv6_gro_receive,
288                 .gro_complete = ipv6_gro_complete,
289         },
290 };
291 
292 static const struct net_offload sit_offload = {
293         .callbacks = {
294                 .gso_segment    = ipv6_gso_segment,
295         },
296 };
297 
298 static int __init ipv6_offload_init(void)
299 {
300 
301         if (tcpv6_offload_init() < 0)
302                 pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
303         if (udp_offload_init() < 0)
304                 pr_crit("%s: Cannot add UDP protocol offload\n", __func__);
305         if (ipv6_exthdrs_offload_init() < 0)
306                 pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
307 
308         dev_add_offload(&ipv6_packet_offload);
309 
310         inet_add_offload(&sit_offload, IPPROTO_IPV6);
311 
312         return 0;
313 }
314 
315 fs_initcall(ipv6_offload_init);
316 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp