2 * Copyright (c) 2017 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * ioam_cache_tunnel_select_node.c
17 * This file implements anycast server selection using ioam data
18 * attached to anycast service selection.
19 * Anycast service is reachable via multiple servers reachable
21 * Works with TCP Anycast application.
22 * Cache entry is created when TCP SYN is received for anycast destination.
23 * Response TCP SYN ACKs for anycast service is compared and selected
24 * response is forwarded.
25 * The functionality is introduced via graph nodes that are hooked into
26 * vnet graph via classifier configs like below:
28 * Enable anycast service selection:
29 * set ioam ip6 sr-tunnel-select oneway
31 * Enable following classifier on the anycast service client facing interface
32 * e.g. anycast service is db06::06 then:
33 * classify session acl-hit-next ip6-node ip6-add-syn-hop-by-hop table-index 0 match l3
34 * ip6 dst db06::06 ioam-encap anycast
36 * Enable following classifier on the interfaces facing the server of anycast service:
37 * classify session acl-hit-next ip6-node ip6-lookup table-index 0 match l3
38 * ip6 src db06::06 ioam-decap anycast
41 #include <vlib/vlib.h>
42 #include <vnet/vnet.h>
43 #include <vppinfra/error.h>
44 #include <vnet/ip/ip.h>
45 #include <vnet/srv6/sr.h>
46 #include <ioam/ip6/ioam_cache.h>
47 #include <vnet/ip/ip6_hop_by_hop.h>
48 #include <vnet/ip/ip6_hop_by_hop_packet.h>
56 /* packet trace format function */
58 format_cache_ts_trace (u8 * s, va_list * args)
60 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
61 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
62 cache_ts_trace_t *t = va_arg (*args, cache_ts_trace_t *);
64 s = format (s, "CACHE: flow_label %d, next index %d",
65 t->flow_label, t->next_index);
69 #define foreach_cache_ts_error \
70 _(RECORDED, "ip6 iOAM headers cached")
74 #define _(sym,str) CACHE_TS_ERROR_##sym,
75 foreach_cache_ts_error
80 static char *cache_ts_error_strings[] = {
81 #define _(sym,string) string,
82 foreach_cache_ts_error
88 IOAM_CACHE_TS_NEXT_POP_HBYH,
89 IOAM_CACHE_TS_ERROR_NEXT_DROP,
94 ip6_ioam_cache_ts_node_fn (vlib_main_t * vm,
95 vlib_node_runtime_t * node, vlib_frame_t * frame)
97 ioam_cache_main_t *cm = &ioam_cache_main;
98 u32 n_left_from, *from, *to_next;
99 cache_ts_next_t next_index;
102 from = vlib_frame_vector_args (frame);
103 n_left_from = frame->n_vectors;
104 next_index = node->cached_next_index;
106 while (n_left_from > 0)
110 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
112 while (n_left_from > 0 && n_left_to_next > 0)
116 u32 next0 = IOAM_CACHE_TS_NEXT_POP_HBYH;
118 ip6_hop_by_hop_header_t *hbh0, *hbh_cmp;
121 u32 cache_ts_index = 0;
122 u8 cache_thread_id = 0;
130 p0 = vlib_get_buffer (vm, bi0);
131 ip0 = vlib_buffer_get_current (p0);
132 if (IP_PROTOCOL_TCP ==
133 ip6_locate_header (p0, ip0, IP_PROTOCOL_TCP, &tcp_offset0))
135 tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0);
136 if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
137 (tcp0->flags & TCP_FLAG_ACK) == TCP_FLAG_ACK)
139 /* Look up and compare */
140 hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
142 if (0 == ioam_cache_ts_lookup (ip0,
149 (tcp0->ack_number), &hbh_cmp,
151 &cache_thread_id, 1))
157 ip6_ioam_analyse_compare_path_delay (hbh0, hbh_cmp,
158 cm->criteria_oneway);
161 /* current syn/ack is worse than the earlier: Drop */
162 next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
163 /* Check if all responses are received or time has exceeded
164 send cached response if yes */
165 ioam_cache_ts_check_and_send (cache_thread_id,
170 /* Update cache with this buffer */
171 /* If successfully updated then skip sending it */
174 ioam_cache_ts_update (cache_thread_id,
181 next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
186 next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
189 else if ((tcp0->flags & TCP_FLAG_RST) == TCP_FLAG_RST)
191 /* Look up and compare */
192 hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
193 if (0 == ioam_cache_ts_lookup (ip0, hbh0->protocol, clib_net_to_host_u16 (tcp0->src_port), clib_net_to_host_u16 (tcp0->dst_port), clib_net_to_host_u32 (tcp0->ack_number), &hbh_cmp, &cache_ts_index, &cache_thread_id, 1)) //response seen
195 next0 = IOAM_CACHE_TS_ERROR_NEXT_DROP;
197 ioam_cache_ts_check_and_send (cache_thread_id,
203 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
205 if (p0->flags & VLIB_BUFFER_IS_TRACED)
207 cache_ts_trace_t *t =
208 vlib_add_trace (vm, node, p0, sizeof (*t));
211 (ip0->ip_version_traffic_class_and_flow_label);
212 t->next_index = next0;
215 /* verify speculative enqueue, maybe switch current next frame */
221 vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
222 to_next, n_left_to_next,
227 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
229 vlib_node_increment_counter (vm, ioam_cache_ts_node.index,
230 CACHE_TS_ERROR_RECORDED, recorded);
231 return frame->n_vectors;
235 * Node for IP6 iOAM header cache
238 VLIB_REGISTER_NODE (ioam_cache_ts_node) =
240 .function = ip6_ioam_cache_ts_node_fn,
241 .name = "ip6-ioam-tunnel-select",
242 .vector_size = sizeof (u32),
243 .format_trace = format_cache_ts_trace,
244 .type = VLIB_NODE_TYPE_INTERNAL,
245 .n_errors = ARRAY_LEN (cache_ts_error_strings),
246 .error_strings = cache_ts_error_strings,
247 .n_next_nodes = IOAM_CACHE_TS_N_NEXT,
248 /* edit / add dispositions here */
251 [IOAM_CACHE_TS_NEXT_POP_HBYH] = "ip6-pop-hop-by-hop",
252 [IOAM_CACHE_TS_ERROR_NEXT_DROP] = "error-drop",
260 } ip6_reset_ts_hbh_trace_t;
262 /* packet trace format function */
264 format_ip6_reset_ts_hbh_trace (u8 * s, va_list * args)
266 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
267 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
268 ip6_reset_ts_hbh_trace_t *t = va_arg (*args,
269 ip6_reset_ts_hbh_trace_t *);
272 format (s, "IP6_IOAM_RESET_TUNNEL_SELECT_HBH: next index %d",
277 #define foreach_ip6_reset_ts_hbh_error \
278 _(PROCESSED, "iOAM Syn/Ack Pkts processed") \
279 _(SAVED, "iOAM Syn Pkts state saved") \
280 _(REMOVED, "iOAM Syn/Ack Pkts state removed")
284 #define _(sym,str) IP6_RESET_TS_HBH_ERROR_##sym,
285 foreach_ip6_reset_ts_hbh_error
287 IP6_RESET_TS_HBH_N_ERROR,
288 } ip6_reset_ts_hbh_error_t;
290 static char *ip6_reset_ts_hbh_error_strings[] = {
291 #define _(sym,string) string,
292 foreach_ip6_reset_ts_hbh_error
296 #define foreach_ip6_ioam_cache_ts_input_next \
297 _(IP6_LOOKUP, "ip6-lookup") \
298 _(DROP, "error-drop")
302 #define _(s,n) IP6_IOAM_CACHE_TS_INPUT_NEXT_##s,
303 foreach_ip6_ioam_cache_ts_input_next
305 IP6_IOAM_CACHE_TS_INPUT_N_NEXT,
306 } ip6_ioam_cache_ts_input_next_t;
309 VLIB_NODE_FN (ip6_reset_ts_hbh_node) (vlib_main_t * vm,
310 vlib_node_runtime_t * node,
311 vlib_frame_t * frame)
313 ioam_cache_main_t *cm = &ioam_cache_main;
314 u32 n_left_from, *from, *to_next;
315 ip_lookup_next_t next_index;
316 u32 processed = 0, cache_ts_added = 0;
318 u8 *rewrite = cm->rewrite;
319 u32 rewrite_length = vec_len (rewrite);
320 ioam_e2e_cache_option_t *e2e = 0;
321 u8 no_of_responses = cm->wait_for_responses;
323 from = vlib_frame_vector_args (frame);
324 n_left_from = frame->n_vectors;
325 next_index = node->cached_next_index;
327 while (n_left_from > 0)
331 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
333 now = vlib_time_now (vm);
334 while (n_left_from >= 4 && n_left_to_next >= 2)
337 vlib_buffer_t *b0, *b1;
339 ip6_header_t *ip0, *ip1;
340 tcp_header_t *tcp0, *tcp1;
341 u32 tcp_offset0, tcp_offset1;
342 ip6_hop_by_hop_header_t *hbh0, *hbh1;
343 u64 *copy_src0, *copy_dst0, *copy_src1, *copy_dst1;
345 u32 pool_index0 = 0, pool_index1 = 0;
347 next0 = next1 = IP6_IOAM_CACHE_TS_INPUT_NEXT_IP6_LOOKUP;
348 /* Prefetch next iteration. */
350 vlib_buffer_t *p2, *p3;
352 p2 = vlib_get_buffer (vm, from[2]);
353 p3 = vlib_get_buffer (vm, from[3]);
355 vlib_prefetch_buffer_header (p2, LOAD);
356 vlib_prefetch_buffer_header (p3, LOAD);
357 CLIB_PREFETCH (p2->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
358 CLIB_PREFETCH (p3->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
362 /* speculatively enqueue b0 to the current next frame */
363 to_next[0] = bi0 = from[0];
364 to_next[1] = bi1 = from[1];
370 b0 = vlib_get_buffer (vm, bi0);
371 b1 = vlib_get_buffer (vm, bi1);
373 ip0 = vlib_buffer_get_current (b0);
374 ip1 = vlib_buffer_get_current (b1);
376 if (IP_PROTOCOL_TCP !=
377 ip6_locate_header (b0, ip0, IP_PROTOCOL_TCP, &tcp_offset0))
381 tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0);
382 if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
383 (tcp0->flags & TCP_FLAG_ACK) == 0)
385 if (no_of_responses > 0)
387 /* Create TS select entry */
388 if (0 == ioam_cache_ts_add (ip0,
394 (tcp0->seq_number) + 1,
395 no_of_responses, now,
396 vm->thread_index, &pool_index0))
401 copy_dst0 = (u64 *) (((u8 *) ip0) - rewrite_length);
402 copy_src0 = (u64 *) ip0;
404 copy_dst0[0] = copy_src0[0];
405 copy_dst0[1] = copy_src0[1];
406 copy_dst0[2] = copy_src0[2];
407 copy_dst0[3] = copy_src0[3];
408 copy_dst0[4] = copy_src0[4];
410 vlib_buffer_advance (b0, -(word) rewrite_length);
411 ip0 = vlib_buffer_get_current (b0);
413 hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
414 /* $$$ tune, rewrite_length is a multiple of 8 */
415 clib_memcpy_fast (hbh0, rewrite, rewrite_length);
417 (ioam_e2e_cache_option_t *) ((u8 *) hbh0 +
418 cm->rewrite_pool_index_offset);
419 e2e->pool_id = (u8) vm->thread_index;
420 e2e->pool_index = pool_index0;
421 ioam_e2e_id_rewrite_handler ((ioam_e2e_id_option_t *)
423 sizeof (ioam_e2e_cache_option_t)),
424 &cm->sr_localsid_ts);
425 /* Patch the protocol chain, insert the h-b-h (type 0) header */
426 hbh0->protocol = ip0->protocol;
429 clib_net_to_host_u16 (ip0->payload_length) + rewrite_length;
430 ip0->payload_length = clib_host_to_net_u16 (new_l0);
435 if (IP_PROTOCOL_TCP !=
436 ip6_locate_header (b1, ip1, IP_PROTOCOL_TCP, &tcp_offset1))
440 tcp1 = (tcp_header_t *) ((u8 *) ip1 + tcp_offset1);
441 if ((tcp1->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
442 (tcp1->flags & TCP_FLAG_ACK) == 0)
444 if (no_of_responses > 0)
446 /* Create TS select entry */
447 if (0 == ioam_cache_ts_add (ip1,
453 (tcp1->seq_number) + 1,
454 no_of_responses, now,
455 vm->thread_index, &pool_index1))
461 copy_dst1 = (u64 *) (((u8 *) ip1) - rewrite_length);
462 copy_src1 = (u64 *) ip1;
464 copy_dst1[0] = copy_src1[0];
465 copy_dst1[1] = copy_src1[1];
466 copy_dst1[2] = copy_src1[2];
467 copy_dst1[3] = copy_src1[3];
468 copy_dst1[4] = copy_src1[4];
470 vlib_buffer_advance (b1, -(word) rewrite_length);
471 ip1 = vlib_buffer_get_current (b1);
473 hbh1 = (ip6_hop_by_hop_header_t *) (ip1 + 1);
474 /* $$$ tune, rewrite_length is a multiple of 8 */
475 clib_memcpy_fast (hbh1, rewrite, rewrite_length);
477 (ioam_e2e_cache_option_t *) ((u8 *) hbh1 +
478 cm->rewrite_pool_index_offset);
479 e2e->pool_id = (u8) vm->thread_index;
480 e2e->pool_index = pool_index1;
481 ioam_e2e_id_rewrite_handler ((ioam_e2e_id_option_t *)
483 sizeof (ioam_e2e_cache_option_t)),
484 &cm->sr_localsid_ts);
485 /* Patch the protocol chain, insert the h-b-h (type 0) header */
486 hbh1->protocol = ip1->protocol;
489 clib_net_to_host_u16 (ip1->payload_length) + rewrite_length;
490 ip1->payload_length = clib_host_to_net_u16 (new_l1);
495 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
497 if (b0->flags & VLIB_BUFFER_IS_TRACED)
499 ip6_reset_ts_hbh_trace_t *t =
500 vlib_add_trace (vm, node, b0, sizeof (*t));
501 t->next_index = next0;
503 if (b1->flags & VLIB_BUFFER_IS_TRACED)
505 ip6_reset_ts_hbh_trace_t *t =
506 vlib_add_trace (vm, node, b1, sizeof (*t));
507 t->next_index = next1;
512 /* verify speculative enqueue, maybe switch current next frame */
513 vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
514 to_next, n_left_to_next,
515 bi0, bi1, next0, next1);
517 while (n_left_from > 0 && n_left_to_next > 0)
525 ip6_hop_by_hop_header_t *hbh0;
526 u64 *copy_src0, *copy_dst0;
530 next0 = IP6_IOAM_CACHE_TS_INPUT_NEXT_IP6_LOOKUP;
531 /* speculatively enqueue b0 to the current next frame */
539 b0 = vlib_get_buffer (vm, bi0);
541 ip0 = vlib_buffer_get_current (b0);
542 if (IP_PROTOCOL_TCP !=
543 ip6_locate_header (b0, ip0, IP_PROTOCOL_TCP, &tcp_offset0))
547 tcp0 = (tcp_header_t *) ((u8 *) ip0 + tcp_offset0);
548 if ((tcp0->flags & TCP_FLAG_SYN) == TCP_FLAG_SYN &&
549 (tcp0->flags & TCP_FLAG_ACK) == 0)
551 if (no_of_responses > 0)
553 /* Create TS select entry */
554 if (0 == ioam_cache_ts_add (ip0,
560 (tcp0->seq_number) + 1,
561 no_of_responses, now,
562 vm->thread_index, &pool_index0))
567 copy_dst0 = (u64 *) (((u8 *) ip0) - rewrite_length);
568 copy_src0 = (u64 *) ip0;
570 copy_dst0[0] = copy_src0[0];
571 copy_dst0[1] = copy_src0[1];
572 copy_dst0[2] = copy_src0[2];
573 copy_dst0[3] = copy_src0[3];
574 copy_dst0[4] = copy_src0[4];
576 vlib_buffer_advance (b0, -(word) rewrite_length);
577 ip0 = vlib_buffer_get_current (b0);
579 hbh0 = (ip6_hop_by_hop_header_t *) (ip0 + 1);
580 /* $$$ tune, rewrite_length is a multiple of 8 */
581 clib_memcpy_fast (hbh0, rewrite, rewrite_length);
583 (ioam_e2e_cache_option_t *) ((u8 *) hbh0 +
584 cm->rewrite_pool_index_offset);
585 e2e->pool_id = (u8) vm->thread_index;
586 e2e->pool_index = pool_index0;
587 ioam_e2e_id_rewrite_handler ((ioam_e2e_id_option_t *)
589 sizeof (ioam_e2e_cache_option_t)),
590 &cm->sr_localsid_ts);
591 /* Patch the protocol chain, insert the h-b-h (type 0) header */
592 hbh0->protocol = ip0->protocol;
595 clib_net_to_host_u16 (ip0->payload_length) + rewrite_length;
596 ip0->payload_length = clib_host_to_net_u16 (new_l0);
600 if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
601 && (b0->flags & VLIB_BUFFER_IS_TRACED)))
603 ip6_reset_ts_hbh_trace_t *t =
604 vlib_add_trace (vm, node, b0, sizeof (*t));
605 t->next_index = next0;
608 /* verify speculative enqueue, maybe switch current next frame */
609 vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
610 to_next, n_left_to_next,
614 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
617 vlib_node_increment_counter (vm, cm->ip6_reset_ts_hbh_node_index,
618 IP6_RESET_TS_HBH_ERROR_PROCESSED, processed);
619 vlib_node_increment_counter (vm, cm->ip6_reset_ts_hbh_node_index,
620 IP6_RESET_TS_HBH_ERROR_SAVED, cache_ts_added);
622 return frame->n_vectors;
626 VLIB_REGISTER_NODE (ip6_reset_ts_hbh_node) =
628 .name = "ip6-add-syn-hop-by-hop",
629 .vector_size = sizeof (u32),
630 .format_trace = format_ip6_reset_ts_hbh_trace,
631 .type = VLIB_NODE_TYPE_INTERNAL,
632 .n_errors = ARRAY_LEN (ip6_reset_ts_hbh_error_strings),
633 .error_strings = ip6_reset_ts_hbh_error_strings,
634 /* See ip/lookup.h */
635 .n_next_nodes = IP6_IOAM_CACHE_TS_INPUT_N_NEXT,
638 #define _(s,n) [IP6_IOAM_CACHE_TS_INPUT_NEXT_##s] = n,
639 foreach_ip6_ioam_cache_ts_input_next
646 #ifndef CLIB_MARCH_VARIANT
647 vlib_node_registration_t ioam_cache_ts_timer_tick_node;
648 #endif /* CLIB_MARCH_VARIANT */
653 } ioam_cache_ts_timer_tick_trace_t;
655 /* packet trace format function */
657 format_ioam_cache_ts_timer_tick_trace (u8 * s, va_list * args)
659 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
660 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
661 ioam_cache_ts_timer_tick_trace_t *t =
662 va_arg (*args, ioam_cache_ts_timer_tick_trace_t *);
664 s = format (s, "IOAM_CACHE_TS_TIMER_TICK: thread index %d",
669 #define foreach_ioam_cache_ts_timer_tick_error \
670 _(TIMER, "Timer events")
674 #define _(sym,str) IOAM_CACHE_TS_TIMER_TICK_ERROR_##sym,
675 foreach_ioam_cache_ts_timer_tick_error
677 IOAM_CACHE_TS_TIMER_TICK_N_ERROR,
678 } ioam_cache_ts_timer_tick_error_t;
680 static char *ioam_cache_ts_timer_tick_error_strings[] = {
681 #define _(sym,string) string,
682 foreach_ioam_cache_ts_timer_tick_error
686 #ifndef CLIB_MARCH_VARIANT
688 ioam_cache_ts_timer_node_enable (vlib_main_t * vm, u8 enable)
690 vlib_node_set_state (vm, ioam_cache_ts_timer_tick_node.index,
692 0 ? VLIB_NODE_STATE_DISABLED :
693 VLIB_NODE_STATE_POLLING);
697 expired_cache_ts_timer_callback (u32 * expired_timers)
699 ioam_cache_main_t *cm = &ioam_cache_main;
702 u32 thread_index = vlib_get_thread_index ();
705 for (i = 0; i < vec_len (expired_timers); i++)
707 /* Get pool index and pool id */
708 pool_index = expired_timers[i] & 0x0FFFFFFF;
710 /* Handle expiration */
711 ioam_cache_ts_send (thread_index, pool_index);
714 vlib_node_increment_counter (cm->vlib_main,
715 ioam_cache_ts_timer_tick_node.index,
716 IOAM_CACHE_TS_TIMER_TICK_ERROR_TIMER, count);
718 #endif /* CLIB_MARCH_VARIANT */
721 ioam_cache_ts_timer_tick_node_fn (vlib_main_t * vm,
722 vlib_node_runtime_t * node,
725 ioam_cache_main_t *cm = &ioam_cache_main;
726 u32 my_thread_index = vlib_get_thread_index ();
727 struct timespec ts, tsrem;
729 tw_timer_expire_timers_16t_2w_512sl (&cm->timer_wheels[my_thread_index],
732 ts.tv_nsec = 1000 * 1000 * IOAM_CACHE_TS_TICK;
733 while (nanosleep (&ts, &tsrem) < 0)
741 VLIB_REGISTER_NODE (ioam_cache_ts_timer_tick_node) = {
742 .function = ioam_cache_ts_timer_tick_node_fn,
743 .name = "ioam-cache-ts-timer-tick",
744 .format_trace = format_ioam_cache_ts_timer_tick_trace,
745 .type = VLIB_NODE_TYPE_INPUT,
747 .n_errors = ARRAY_LEN(ioam_cache_ts_timer_tick_error_strings),
748 .error_strings = ioam_cache_ts_timer_tick_error_strings,
752 .state = VLIB_NODE_STATE_DISABLED,
754 /* edit / add dispositions here */
762 * fd.io coding-style-patch-verification: ON
765 * eval: (c-set-style "gnu")