2 * net/sched/cls_rsvp.h Template file for RSVPv[46] classifiers.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
13 Comparing to general packet classification problem,
14 RSVP needs only sevaral relatively simple rules:
16 * (dst, protocol) are always specified,
17 so that we are able to hash them.
18 * src may be exact, or may be wildcard, so that
19 we can keep a hash table plus one wildcard entry.
20 * source port (or flow label) is important only if src is given.
24 We use a two level hash table: The top level is keyed by
25 destination address and protocol ID, every bucket contains a list
26 of "rsvp sessions", identified by destination address, protocol and
27 DPI(="Destination Port ID"): triple (key, mask, offset).
29 Every bucket has a smaller hash table keyed by source address
30 (cf. RSVP flowspec) and one wildcard entry for wildcard reservations.
31 Every bucket is again a list of "RSVP flows", selected by
32 source address and SPI(="Source Port ID" here rather than
33 "security parameter index"): triple (key, mask, offset).
36 NOTE 1. All the packets with IPv6 extension headers (but AH and ESP)
37 and all fragmented packets go to the best-effort traffic class.
40 NOTE 2. Two "port id"'s seems to be redundant, rfc2207 requires
41 only one "Generalized Port Identifier". So that for classic
42 ah, esp (and udp,tcp) both *pi should coincide or one of them
45 At first sight, this redundancy is just a waste of CPU
46 resources. But DPI and SPI add the possibility to assign different
47 priorities to GPIs. Look also at note 4 about tunnels below.
50 NOTE 3. One complication is the case of tunneled packets.
51 We implement it as following: if the first lookup
52 matches a special session with "tunnelhdr" value not zero,
53 flowid doesn't contain the true flow ID, but the tunnel ID (1...255).
54 In this case, we pull tunnelhdr bytes and restart lookup
55 with tunnel ID added to the list of keys. Simple and stupid 8)8)
56 It's enough for PIMREG and IPIP.
59 NOTE 4. Two GPIs make it possible to parse even GRE packets.
60 F.e. DPI can select ETH_P_IP (and necessary flags to make
61 tunnelhdr correct) in GRE protocol field and SPI matches
62 GRE key. Is it not nice? 8)8)
65 Well, as result, despite its simplicity, we get a pretty
66 powerful classification engine. */
74 struct rsvp_session *ht[256];
79 struct rsvp_session *next;
80 __be32 dst[RSVP_DST_LEN];
81 struct tc_rsvp_gpi dpi;
84 /* 16 (src,sport) hash slots, and one wildcard source slot */
85 struct rsvp_filter *ht[16+1];
91 struct rsvp_filter *next;
92 __be32 src[RSVP_DST_LEN];
93 struct tc_rsvp_gpi spi;
96 struct tcf_result res;
100 struct rsvp_session *sess;
103 static __inline__ unsigned hash_dst(__be32 *dst, u8 protocol, u8 tunnelid)
105 unsigned h = (__force __u32)dst[RSVP_DST_LEN-1];
108 return (h ^ protocol ^ tunnelid) & 0xFF;
111 static __inline__ unsigned hash_src(__be32 *src)
113 unsigned h = (__force __u32)src[RSVP_DST_LEN-1];
120 static struct tcf_ext_map rsvp_ext_map = {
121 .police = TCA_RSVP_POLICE,
122 .action = TCA_RSVP_ACT
125 #define RSVP_APPLY_RESULT() \
127 int r = tcf_exts_exec(skb, &f->exts, res); \
134 static int rsvp_classify(struct sk_buff *skb, struct tcf_proto *tp,
135 struct tcf_result *res)
137 struct rsvp_session **sht = ((struct rsvp_head*)tp->root)->ht;
138 struct rsvp_session *s;
139 struct rsvp_filter *f;
145 #if RSVP_DST_LEN == 4
146 struct ipv6hdr *nhptr = ipv6_hdr(skb);
148 struct iphdr *nhptr = ip_hdr(skb);
153 #if RSVP_DST_LEN == 4
154 src = &nhptr->saddr.s6_addr32[0];
155 dst = &nhptr->daddr.s6_addr32[0];
156 protocol = nhptr->nexthdr;
157 xprt = ((u8*)nhptr) + sizeof(struct ipv6hdr);
161 protocol = nhptr->protocol;
162 xprt = ((u8*)nhptr) + (nhptr->ihl<<2);
163 if (nhptr->frag_off & htons(IP_MF|IP_OFFSET))
167 h1 = hash_dst(dst, protocol, tunnelid);
170 for (s = sht[h1]; s; s = s->next) {
171 if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&
172 protocol == s->protocol &&
173 !(s->dpi.mask & (*(u32*)(xprt+s->dpi.offset)^s->dpi.key))
174 #if RSVP_DST_LEN == 4
175 && dst[0] == s->dst[0]
176 && dst[1] == s->dst[1]
177 && dst[2] == s->dst[2]
179 && tunnelid == s->tunnelid) {
181 for (f = s->ht[h2]; f; f = f->next) {
182 if (src[RSVP_DST_LEN-1] == f->src[RSVP_DST_LEN-1] &&
183 !(f->spi.mask & (*(u32*)(xprt+f->spi.offset)^f->spi.key))
184 #if RSVP_DST_LEN == 4
185 && src[0] == f->src[0]
186 && src[1] == f->src[1]
187 && src[2] == f->src[2]
194 if (f->tunnelhdr == 0)
197 tunnelid = f->res.classid;
198 nhptr = (void*)(xprt + f->tunnelhdr - sizeof(*nhptr));
203 /* And wildcard bucket... */
204 for (f = s->ht[16]; f; f = f->next) {
215 static unsigned long rsvp_get(struct tcf_proto *tp, u32 handle)
217 struct rsvp_session **sht = ((struct rsvp_head*)tp->root)->ht;
218 struct rsvp_session *s;
219 struct rsvp_filter *f;
220 unsigned h1 = handle&0xFF;
221 unsigned h2 = (handle>>8)&0xFF;
226 for (s = sht[h1]; s; s = s->next) {
227 for (f = s->ht[h2]; f; f = f->next) {
228 if (f->handle == handle)
229 return (unsigned long)f;
235 static void rsvp_put(struct tcf_proto *tp, unsigned long f)
239 static int rsvp_init(struct tcf_proto *tp)
241 struct rsvp_head *data;
243 data = kzalloc(sizeof(struct rsvp_head), GFP_KERNEL);
252 rsvp_delete_filter(struct tcf_proto *tp, struct rsvp_filter *f)
254 tcf_unbind_filter(tp, &f->res);
255 tcf_exts_destroy(tp, &f->exts);
259 static void rsvp_destroy(struct tcf_proto *tp)
261 struct rsvp_head *data = xchg(&tp->root, NULL);
262 struct rsvp_session **sht;
270 for (h1=0; h1<256; h1++) {
271 struct rsvp_session *s;
273 while ((s = sht[h1]) != NULL) {
276 for (h2=0; h2<=16; h2++) {
277 struct rsvp_filter *f;
279 while ((f = s->ht[h2]) != NULL) {
281 rsvp_delete_filter(tp, f);
290 static int rsvp_delete(struct tcf_proto *tp, unsigned long arg)
292 struct rsvp_filter **fp, *f = (struct rsvp_filter*)arg;
293 unsigned h = f->handle;
294 struct rsvp_session **sp;
295 struct rsvp_session *s = f->sess;
298 for (fp = &s->ht[(h>>8)&0xFF]; *fp; fp = &(*fp)->next) {
303 rsvp_delete_filter(tp, f);
307 for (i=0; i<=16; i++)
311 /* OK, session has no flows */
312 for (sp = &((struct rsvp_head*)tp->root)->ht[h&0xFF];
313 *sp; sp = &(*sp)->next) {
330 static unsigned gen_handle(struct tcf_proto *tp, unsigned salt)
332 struct rsvp_head *data = tp->root;
337 if ((data->hgenerator += 0x10000) == 0)
338 data->hgenerator = 0x10000;
339 h = data->hgenerator|salt;
340 if (rsvp_get(tp, h) == 0)
346 static int tunnel_bts(struct rsvp_head *data)
348 int n = data->tgenerator>>5;
349 u32 b = 1<<(data->tgenerator&0x1F);
357 static void tunnel_recycle(struct rsvp_head *data)
359 struct rsvp_session **sht = data->ht;
363 memset(tmap, 0, sizeof(tmap));
365 for (h1=0; h1<256; h1++) {
366 struct rsvp_session *s;
367 for (s = sht[h1]; s; s = s->next) {
368 for (h2=0; h2<=16; h2++) {
369 struct rsvp_filter *f;
371 for (f = s->ht[h2]; f; f = f->next) {
372 if (f->tunnelhdr == 0)
374 data->tgenerator = f->res.classid;
381 memcpy(data->tmap, tmap, sizeof(tmap));
384 static u32 gen_tunnel(struct rsvp_head *data)
388 for (k=0; k<2; k++) {
389 for (i=255; i>0; i--) {
390 if (++data->tgenerator == 0)
391 data->tgenerator = 1;
392 if (tunnel_bts(data))
393 return data->tgenerator;
395 tunnel_recycle(data);
400 static int rsvp_change(struct tcf_proto *tp, unsigned long base,
405 struct rsvp_head *data = tp->root;
406 struct rsvp_filter *f, **fp;
407 struct rsvp_session *s, **sp;
408 struct tc_rsvp_pinfo *pinfo = NULL;
409 struct nlattr *opt = tca[TCA_OPTIONS-1];
410 struct nlattr *tb[TCA_RSVP_MAX + 1];
417 return handle ? -EINVAL : 0;
419 err = nla_parse_nested(tb, TCA_RSVP_MAX, opt, NULL);
423 err = tcf_exts_validate(tp, tb, tca[TCA_RATE-1], &e, &rsvp_ext_map);
427 if ((f = (struct rsvp_filter*)*arg) != NULL) {
428 /* Node exists: adjust only classid */
430 if (f->handle != handle && handle)
432 if (tb[TCA_RSVP_CLASSID-1]) {
433 f->res.classid = nla_get_u32(tb[TCA_RSVP_CLASSID-1]);
434 tcf_bind_filter(tp, &f->res, base);
437 tcf_exts_change(tp, &f->exts, &e);
441 /* Now more serious part... */
445 if (tb[TCA_RSVP_DST-1] == NULL)
449 f = kzalloc(sizeof(struct rsvp_filter), GFP_KERNEL);
454 if (tb[TCA_RSVP_SRC-1]) {
456 if (nla_len(tb[TCA_RSVP_SRC-1]) != sizeof(f->src))
458 memcpy(f->src, nla_data(tb[TCA_RSVP_SRC-1]), sizeof(f->src));
459 h2 = hash_src(f->src);
461 if (tb[TCA_RSVP_PINFO-1]) {
463 if (nla_len(tb[TCA_RSVP_PINFO-1]) < sizeof(struct tc_rsvp_pinfo))
465 pinfo = nla_data(tb[TCA_RSVP_PINFO-1]);
467 f->tunnelhdr = pinfo->tunnelhdr;
469 if (tb[TCA_RSVP_CLASSID-1]) {
471 if (nla_len(tb[TCA_RSVP_CLASSID-1]) != 4)
473 f->res.classid = nla_get_u32(tb[TCA_RSVP_CLASSID-1]);
477 if (nla_len(tb[TCA_RSVP_DST-1]) != sizeof(f->src))
479 dst = nla_data(tb[TCA_RSVP_DST-1]);
480 h1 = hash_dst(dst, pinfo ? pinfo->protocol : 0, pinfo ? pinfo->tunnelid : 0);
483 if ((f->handle = gen_handle(tp, h1 | (h2<<8))) == 0)
488 if (f->res.classid > 255)
492 if (f->res.classid == 0 &&
493 (f->res.classid = gen_tunnel(data)) == 0)
497 for (sp = &data->ht[h1]; (s=*sp) != NULL; sp = &s->next) {
498 if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&
499 pinfo && pinfo->protocol == s->protocol &&
500 memcmp(&pinfo->dpi, &s->dpi, sizeof(s->dpi)) == 0
501 #if RSVP_DST_LEN == 4
502 && dst[0] == s->dst[0]
503 && dst[1] == s->dst[1]
504 && dst[2] == s->dst[2]
506 && pinfo->tunnelid == s->tunnelid) {
509 /* OK, we found appropriate session */
514 if (f->tunnelhdr == 0)
515 tcf_bind_filter(tp, &f->res, base);
517 tcf_exts_change(tp, &f->exts, &e);
519 for (fp = &s->ht[h2]; *fp; fp = &(*fp)->next)
520 if (((*fp)->spi.mask&f->spi.mask) != f->spi.mask)
526 *arg = (unsigned long)f;
531 /* No session found. Create new one. */
534 s = kzalloc(sizeof(struct rsvp_session), GFP_KERNEL);
537 memcpy(s->dst, dst, sizeof(s->dst));
541 s->protocol = pinfo->protocol;
542 s->tunnelid = pinfo->tunnelid;
544 for (sp = &data->ht[h1]; *sp; sp = &(*sp)->next) {
545 if (((*sp)->dpi.mask&s->dpi.mask) != s->dpi.mask)
557 tcf_exts_destroy(tp, &e);
561 static void rsvp_walk(struct tcf_proto *tp, struct tcf_walker *arg)
563 struct rsvp_head *head = tp->root;
569 for (h = 0; h < 256; h++) {
570 struct rsvp_session *s;
572 for (s = head->ht[h]; s; s = s->next) {
573 for (h1 = 0; h1 <= 16; h1++) {
574 struct rsvp_filter *f;
576 for (f = s->ht[h1]; f; f = f->next) {
577 if (arg->count < arg->skip) {
581 if (arg->fn(tp, (unsigned long)f, arg) < 0) {
592 static int rsvp_dump(struct tcf_proto *tp, unsigned long fh,
593 struct sk_buff *skb, struct tcmsg *t)
595 struct rsvp_filter *f = (struct rsvp_filter*)fh;
596 struct rsvp_session *s;
597 unsigned char *b = skb_tail_pointer(skb);
599 struct tc_rsvp_pinfo pinfo;
605 t->tcm_handle = f->handle;
607 nest = nla_nest_start(skb, TCA_OPTIONS);
609 goto nla_put_failure;
611 NLA_PUT(skb, TCA_RSVP_DST, sizeof(s->dst), &s->dst);
614 pinfo.protocol = s->protocol;
615 pinfo.tunnelid = s->tunnelid;
616 pinfo.tunnelhdr = f->tunnelhdr;
618 NLA_PUT(skb, TCA_RSVP_PINFO, sizeof(pinfo), &pinfo);
620 NLA_PUT_U32(skb, TCA_RSVP_CLASSID, f->res.classid);
621 if (((f->handle>>8)&0xFF) != 16)
622 NLA_PUT(skb, TCA_RSVP_SRC, sizeof(f->src), f->src);
624 if (tcf_exts_dump(skb, &f->exts, &rsvp_ext_map) < 0)
625 goto nla_put_failure;
627 nla_nest_end(skb, nest);
629 if (tcf_exts_dump_stats(skb, &f->exts, &rsvp_ext_map) < 0)
630 goto nla_put_failure;
638 static struct tcf_proto_ops RSVP_OPS = {
641 .classify = rsvp_classify,
643 .destroy = rsvp_destroy,
646 .change = rsvp_change,
647 .delete = rsvp_delete,
650 .owner = THIS_MODULE,
653 static int __init init_rsvp(void)
655 return register_tcf_proto_ops(&RSVP_OPS);
658 static void __exit exit_rsvp(void)
660 unregister_tcf_proto_ops(&RSVP_OPS);
663 module_init(init_rsvp)
664 module_exit(exit_rsvp)