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

TOMOYO Linux Cross Reference
Linux/net/hsr/hsr_forward.c

Version: ~ [ linux-5.1-rc1 ] ~ [ linux-5.0.2 ] ~ [ linux-4.20.16 ] ~ [ linux-4.19.29 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.106 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.163 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.176 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.136 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.63 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /* Copyright 2011-2014 Autronica Fire and Security AS
  2  *
  3  * This program is free software; you can redistribute it and/or modify it
  4  * under the terms of the GNU General Public License as published by the Free
  5  * Software Foundation; either version 2 of the License, or (at your option)
  6  * any later version.
  7  *
  8  * Author(s):
  9  *      2011-2014 Arvid Brodin, arvid.brodin@alten.se
 10  */
 11 
 12 #include "hsr_forward.h"
 13 #include <linux/types.h>
 14 #include <linux/skbuff.h>
 15 #include <linux/etherdevice.h>
 16 #include <linux/if_vlan.h>
 17 #include "hsr_main.h"
 18 #include "hsr_framereg.h"
 19 
 20 
 21 struct hsr_node;
 22 
 23 struct hsr_frame_info {
 24         struct sk_buff *skb_std;
 25         struct sk_buff *skb_hsr;
 26         struct hsr_port *port_rcv;
 27         struct hsr_node *node_src;
 28         u16 sequence_nr;
 29         bool is_supervision;
 30         bool is_vlan;
 31         bool is_local_dest;
 32         bool is_local_exclusive;
 33 };
 34 
 35 
 36 /* The uses I can see for these HSR supervision frames are:
 37  * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type =
 38  *    22") to reset any sequence_nr counters belonging to that node. Useful if
 39  *    the other node's counter has been reset for some reason.
 40  *    --
 41  *    Or not - resetting the counter and bridging the frame would create a
 42  *    loop, unfortunately.
 43  *
 44  * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck
 45  *    frame is received from a particular node, we know something is wrong.
 46  *    We just register these (as with normal frames) and throw them away.
 47  *
 48  * 3) Allow different MAC addresses for the two slave interfaces, using the
 49  *    MacAddressA field.
 50  */
 51 static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb)
 52 {
 53         struct ethhdr *ethHdr;
 54         struct hsr_sup_tag *hsrSupTag;
 55         struct hsrv1_ethhdr_sp *hsrV1Hdr;
 56 
 57         WARN_ON_ONCE(!skb_mac_header_was_set(skb));
 58         ethHdr = (struct ethhdr *) skb_mac_header(skb);
 59 
 60         /* Correct addr? */
 61         if (!ether_addr_equal(ethHdr->h_dest,
 62                               hsr->sup_multicast_addr))
 63                 return false;
 64 
 65         /* Correct ether type?. */
 66         if (!(ethHdr->h_proto == htons(ETH_P_PRP)
 67                         || ethHdr->h_proto == htons(ETH_P_HSR)))
 68                 return false;
 69 
 70         /* Get the supervision header from correct location. */
 71         if (ethHdr->h_proto == htons(ETH_P_HSR)) { /* Okay HSRv1. */
 72                 hsrV1Hdr = (struct hsrv1_ethhdr_sp *) skb_mac_header(skb);
 73                 if (hsrV1Hdr->hsr.encap_proto != htons(ETH_P_PRP))
 74                         return false;
 75 
 76                 hsrSupTag = &hsrV1Hdr->hsr_sup;
 77         } else {
 78                 hsrSupTag = &((struct hsrv0_ethhdr_sp *) skb_mac_header(skb))->hsr_sup;
 79         }
 80 
 81         if ((hsrSupTag->HSR_TLV_Type != HSR_TLV_ANNOUNCE) &&
 82             (hsrSupTag->HSR_TLV_Type != HSR_TLV_LIFE_CHECK))
 83                 return false;
 84         if ((hsrSupTag->HSR_TLV_Length != 12) &&
 85                         (hsrSupTag->HSR_TLV_Length !=
 86                                         sizeof(struct hsr_sup_payload)))
 87                 return false;
 88 
 89         return true;
 90 }
 91 
 92 
 93 static struct sk_buff *create_stripped_skb(struct sk_buff *skb_in,
 94                                            struct hsr_frame_info *frame)
 95 {
 96         struct sk_buff *skb;
 97         int copylen;
 98         unsigned char *dst, *src;
 99 
100         skb_pull(skb_in, HSR_HLEN);
101         skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
102         skb_push(skb_in, HSR_HLEN);
103         if (skb == NULL)
104                 return NULL;
105 
106         skb_reset_mac_header(skb);
107 
108         if (skb->ip_summed == CHECKSUM_PARTIAL)
109                 skb->csum_start -= HSR_HLEN;
110 
111         copylen = 2*ETH_ALEN;
112         if (frame->is_vlan)
113                 copylen += VLAN_HLEN;
114         src = skb_mac_header(skb_in);
115         dst = skb_mac_header(skb);
116         memcpy(dst, src, copylen);
117 
118         skb->protocol = eth_hdr(skb)->h_proto;
119         return skb;
120 }
121 
122 static struct sk_buff *frame_get_stripped_skb(struct hsr_frame_info *frame,
123                                               struct hsr_port *port)
124 {
125         if (!frame->skb_std)
126                 frame->skb_std = create_stripped_skb(frame->skb_hsr, frame);
127         return skb_clone(frame->skb_std, GFP_ATOMIC);
128 }
129 
130 
131 static void hsr_fill_tag(struct sk_buff *skb, struct hsr_frame_info *frame,
132                          struct hsr_port *port, u8 protoVersion)
133 {
134         struct hsr_ethhdr *hsr_ethhdr;
135         int lane_id;
136         int lsdu_size;
137 
138         if (port->type == HSR_PT_SLAVE_A)
139                 lane_id = 0;
140         else
141                 lane_id = 1;
142 
143         lsdu_size = skb->len - 14;
144         if (frame->is_vlan)
145                 lsdu_size -= 4;
146 
147         hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
148 
149         set_hsr_tag_path(&hsr_ethhdr->hsr_tag, lane_id);
150         set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
151         hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
152         hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
153         hsr_ethhdr->ethhdr.h_proto = htons(protoVersion ?
154                         ETH_P_HSR : ETH_P_PRP);
155 }
156 
157 static struct sk_buff *create_tagged_skb(struct sk_buff *skb_o,
158                                          struct hsr_frame_info *frame,
159                                          struct hsr_port *port)
160 {
161         int movelen;
162         unsigned char *dst, *src;
163         struct sk_buff *skb;
164 
165         /* Create the new skb with enough headroom to fit the HSR tag */
166         skb = __pskb_copy(skb_o, skb_headroom(skb_o) + HSR_HLEN, GFP_ATOMIC);
167         if (skb == NULL)
168                 return NULL;
169         skb_reset_mac_header(skb);
170 
171         if (skb->ip_summed == CHECKSUM_PARTIAL)
172                 skb->csum_start += HSR_HLEN;
173 
174         movelen = ETH_HLEN;
175         if (frame->is_vlan)
176                 movelen += VLAN_HLEN;
177 
178         src = skb_mac_header(skb);
179         dst = skb_push(skb, HSR_HLEN);
180         memmove(dst, src, movelen);
181         skb_reset_mac_header(skb);
182 
183         hsr_fill_tag(skb, frame, port, port->hsr->protVersion);
184 
185         return skb;
186 }
187 
188 /* If the original frame was an HSR tagged frame, just clone it to be sent
189  * unchanged. Otherwise, create a private frame especially tagged for 'port'.
190  */
191 static struct sk_buff *frame_get_tagged_skb(struct hsr_frame_info *frame,
192                                             struct hsr_port *port)
193 {
194         if (frame->skb_hsr)
195                 return skb_clone(frame->skb_hsr, GFP_ATOMIC);
196 
197         if ((port->type != HSR_PT_SLAVE_A) && (port->type != HSR_PT_SLAVE_B)) {
198                 WARN_ONCE(1, "HSR: Bug: trying to create a tagged frame for a non-ring port");
199                 return NULL;
200         }
201 
202         return create_tagged_skb(frame->skb_std, frame, port);
203 }
204 
205 
206 static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
207                                struct hsr_node *node_src)
208 {
209         bool was_multicast_frame;
210         int res;
211 
212         was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
213         hsr_addr_subst_source(node_src, skb);
214         skb_pull(skb, ETH_HLEN);
215         res = netif_rx(skb);
216         if (res == NET_RX_DROP) {
217                 dev->stats.rx_dropped++;
218         } else {
219                 dev->stats.rx_packets++;
220                 dev->stats.rx_bytes += skb->len;
221                 if (was_multicast_frame)
222                         dev->stats.multicast++;
223         }
224 }
225 
226 static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
227                     struct hsr_frame_info *frame)
228 {
229         if (frame->port_rcv->type == HSR_PT_MASTER) {
230                 hsr_addr_subst_dest(frame->node_src, skb, port);
231 
232                 /* Address substitution (IEC62439-3 pp 26, 50): replace mac
233                  * address of outgoing frame with that of the outgoing slave's.
234                  */
235                 ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
236         }
237         return dev_queue_xmit(skb);
238 }
239 
240 
241 /* Forward the frame through all devices except:
242  * - Back through the receiving device
243  * - If it's a HSR frame: through a device where it has passed before
244  * - To the local HSR master only if the frame is directly addressed to it, or
245  *   a non-supervision multicast or broadcast frame.
246  *
247  * HSR slave devices should insert a HSR tag into the frame, or forward the
248  * frame unchanged if it's already tagged. Interlink devices should strip HSR
249  * tags if they're of the non-HSR type (but only after duplicate discard). The
250  * master device always strips HSR tags.
251  */
252 static void hsr_forward_do(struct hsr_frame_info *frame)
253 {
254         struct hsr_port *port;
255         struct sk_buff *skb;
256 
257         hsr_for_each_port(frame->port_rcv->hsr, port) {
258                 /* Don't send frame back the way it came */
259                 if (port == frame->port_rcv)
260                         continue;
261 
262                 /* Don't deliver locally unless we should */
263                 if ((port->type == HSR_PT_MASTER) && !frame->is_local_dest)
264                         continue;
265 
266                 /* Deliver frames directly addressed to us to master only */
267                 if ((port->type != HSR_PT_MASTER) && frame->is_local_exclusive)
268                         continue;
269 
270                 /* Don't send frame over port where it has been sent before */
271                 if (hsr_register_frame_out(port, frame->node_src,
272                                            frame->sequence_nr))
273                         continue;
274 
275                 if (frame->is_supervision && (port->type == HSR_PT_MASTER)) {
276                         hsr_handle_sup_frame(frame->skb_hsr,
277                                              frame->node_src,
278                                              frame->port_rcv);
279                         continue;
280                 }
281 
282                 if (port->type != HSR_PT_MASTER)
283                         skb = frame_get_tagged_skb(frame, port);
284                 else
285                         skb = frame_get_stripped_skb(frame, port);
286                 if (skb == NULL) {
287                         /* FIXME: Record the dropped frame? */
288                         continue;
289                 }
290 
291                 skb->dev = port->dev;
292                 if (port->type == HSR_PT_MASTER)
293                         hsr_deliver_master(skb, port->dev, frame->node_src);
294                 else
295                         hsr_xmit(skb, port, frame);
296         }
297 }
298 
299 
300 static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
301                              struct hsr_frame_info *frame)
302 {
303         if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
304                 frame->is_local_exclusive = true;
305                 skb->pkt_type = PACKET_HOST;
306         } else {
307                 frame->is_local_exclusive = false;
308         }
309 
310         if ((skb->pkt_type == PACKET_HOST) ||
311             (skb->pkt_type == PACKET_MULTICAST) ||
312             (skb->pkt_type == PACKET_BROADCAST)) {
313                 frame->is_local_dest = true;
314         } else {
315                 frame->is_local_dest = false;
316         }
317 }
318 
319 
320 static int hsr_fill_frame_info(struct hsr_frame_info *frame,
321                                struct sk_buff *skb, struct hsr_port *port)
322 {
323         struct ethhdr *ethhdr;
324         unsigned long irqflags;
325 
326         frame->is_supervision = is_supervision_frame(port->hsr, skb);
327         frame->node_src = hsr_get_node(port, skb, frame->is_supervision);
328         if (frame->node_src == NULL)
329                 return -1; /* Unknown node and !is_supervision, or no mem */
330 
331         ethhdr = (struct ethhdr *) skb_mac_header(skb);
332         frame->is_vlan = false;
333         if (ethhdr->h_proto == htons(ETH_P_8021Q)) {
334                 frame->is_vlan = true;
335                 /* FIXME: */
336                 WARN_ONCE(1, "HSR: VLAN not yet supported");
337         }
338         if (ethhdr->h_proto == htons(ETH_P_PRP)
339                         || ethhdr->h_proto == htons(ETH_P_HSR)) {
340                 frame->skb_std = NULL;
341                 frame->skb_hsr = skb;
342                 frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
343         } else {
344                 frame->skb_std = skb;
345                 frame->skb_hsr = NULL;
346                 /* Sequence nr for the master node */
347                 spin_lock_irqsave(&port->hsr->seqnr_lock, irqflags);
348                 frame->sequence_nr = port->hsr->sequence_nr;
349                 port->hsr->sequence_nr++;
350                 spin_unlock_irqrestore(&port->hsr->seqnr_lock, irqflags);
351         }
352 
353         frame->port_rcv = port;
354         check_local_dest(port->hsr, skb, frame);
355 
356         return 0;
357 }
358 
359 /* Must be called holding rcu read lock (because of the port parameter) */
360 void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
361 {
362         struct hsr_frame_info frame;
363 
364         if (skb_mac_header(skb) != skb->data) {
365                 WARN_ONCE(1, "%s:%d: Malformed frame (port_src %s)\n",
366                           __FILE__, __LINE__, port->dev->name);
367                 goto out_drop;
368         }
369 
370         if (hsr_fill_frame_info(&frame, skb, port) < 0)
371                 goto out_drop;
372         hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
373         hsr_forward_do(&frame);
374 
375         if (frame.skb_hsr != NULL)
376                 kfree_skb(frame.skb_hsr);
377         if (frame.skb_std != NULL)
378                 kfree_skb(frame.skb_std);
379         return;
380 
381 out_drop:
382         port->dev->stats.tx_dropped++;
383         kfree_skb(skb);
384 }
385 

~ [ 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