URL https://opencores.org/ocsvn/or1k/or1k/trunk

Subversion Repositories or1k

[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [net/] [sched/] [cls_rsvp.h] - Blame information for rev 1774

Go to most recent revision | Details | Compare with Previous | View Log


/*
 * net/sched/cls_rsvp.h Template file for RSVPv[46] classifiers.
 *
 *              This program is free software; you can redistribute it and/or
 *              modify it under the terms of the GNU General Public License
 *              as published by the Free Software Foundation; either version
 *              2 of the License, or (at your option) any later version.
 *
 * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 */
 
/*
   Comparing to general packet classification problem,
   RSVP needs only sevaral relatively simple rules:
 
   * (dst, protocol) are always specified,
     so that we are able to hash them.
   * src may be exact, or may be wildcard, so that
     we can keep a hash table plus one wildcard entry.
   * source port (or flow label) is important only if src is given.
 
   IMPLEMENTATION.
 
   We use a two level hash table: The top level is keyed by
   destination address and protocol ID, every bucket contains a list
   of "rsvp sessions", identified by destination address, protocol and
   DPI(="Destination Port ID"): triple (key, mask, offset).
 
   Every bucket has a smaller hash table keyed by source address
   (cf. RSVP flowspec) and one wildcard entry for wildcard reservations.
   Every bucket is again a list of "RSVP flows", selected by
   source address and SPI(="Source Port ID" here rather than
   "security parameter index"): triple (key, mask, offset).
 
 
   NOTE 1. All the packets with IPv6 extension headers (but AH and ESP)
   and all fragmented packets go to the best-effort traffic class.
 
 
   NOTE 2. Two "port id"'s seems to be redundant, rfc2207 requires
   only one "Generalized Port Identifier". So that for classic
   ah, esp (and udp,tcp) both *pi should coincide or one of them
   should be wildcard.
 
   At first sight, this redundancy is just a waste of CPU
   resources. But DPI and SPI add the possibility to assign different
   priorities to GPIs. Look also at note 4 about tunnels below.
 
 
   NOTE 3. One complication is the case of tunneled packets.
   We implement it as following: if the first lookup
   matches a special session with "tunnelhdr" value not zero,
   flowid doesn't contain the true flow ID, but the tunnel ID (1...255).
   In this case, we pull tunnelhdr bytes and restart lookup
   with tunnel ID added to the list of keys. Simple and stupid 8)8)
   It's enough for PIMREG and IPIP.
 
 
   NOTE 4. Two GPIs make it possible to parse even GRE packets.
   F.e. DPI can select ETH_P_IP (and necessary flags to make
   tunnelhdr correct) in GRE protocol field and SPI matches
   GRE key. Is it not nice? 8)8)
 
 
   Well, as result, despite its simplicity, we get a pretty
   powerful classification engine.  */
 
#include <linux/config.h>
 
struct rsvp_head
{
        u32                     tmap[256/32];
        u32                     hgenerator;
        u8                      tgenerator;
        struct rsvp_session     *ht[256];
};
 
struct rsvp_session
{
        struct rsvp_session     *next;
        u32                     dst[RSVP_DST_LEN];
        struct tc_rsvp_gpi      dpi;
        u8                      protocol;
        u8                      tunnelid;
        /* 16 (src,sport) hash slots, and one wildcard source slot */
        struct rsvp_filter      *ht[16+1];
};
 
 
struct rsvp_filter
{
        struct rsvp_filter      *next;
        u32                     src[RSVP_DST_LEN];
        struct tc_rsvp_gpi      spi;
        u8                      tunnelhdr;
 
        struct tcf_result       res;
#ifdef CONFIG_NET_CLS_POLICE
        struct tcf_police       *police;
#endif
 
        u32                     handle;
        struct rsvp_session     *sess;
};
 
static __inline__ unsigned hash_dst(u32 *dst, u8 protocol, u8 tunnelid)
{
        unsigned h = dst[RSVP_DST_LEN-1];
        h ^= h>>16;
        h ^= h>>8;
        return (h ^ protocol ^ tunnelid) & 0xFF;
}
 
static __inline__ unsigned hash_src(u32 *src)
{
        unsigned h = src[RSVP_DST_LEN-1];
        h ^= h>>16;
        h ^= h>>8;
        h ^= h>>4;
        return h & 0xF;
}
 
#ifdef CONFIG_NET_CLS_POLICE
#define RSVP_POLICE() \
if (f->police) { \
        int pol_res = tcf_police(skb, f->police); \
        if (pol_res < 0) continue; \
        if (pol_res) return pol_res; \
}
#else
#define RSVP_POLICE()
#endif
 
 
static int rsvp_classify(struct sk_buff *skb, struct tcf_proto *tp,
                         struct tcf_result *res)
{
        struct rsvp_session **sht = ((struct rsvp_head*)tp->root)->ht;
        struct rsvp_session *s;
        struct rsvp_filter *f;
        unsigned h1, h2;
        u32 *dst, *src;
        u8 protocol;
        u8 tunnelid = 0;
        u8 *xprt;
#if RSVP_DST_LEN == 4
        struct ipv6hdr *nhptr = skb->nh.ipv6h;
#else
        struct iphdr *nhptr = skb->nh.iph;
#endif
 
restart:
 
#if RSVP_DST_LEN == 4
        src = &nhptr->saddr.s6_addr32[0];
        dst = &nhptr->daddr.s6_addr32[0];
        protocol = nhptr->nexthdr;
        xprt = ((u8*)nhptr) + sizeof(struct ipv6hdr);
#else
        src = &nhptr->saddr;
        dst = &nhptr->daddr;
        protocol = nhptr->protocol;
        xprt = ((u8*)nhptr) + (nhptr->ihl<<2);
        if (nhptr->frag_off&__constant_htons(IP_MF|IP_OFFSET))
                return -1;
#endif
 
        h1 = hash_dst(dst, protocol, tunnelid);
        h2 = hash_src(src);
 
        for (s = sht[h1]; s; s = s->next) {
                if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&
                    protocol == s->protocol &&
                    !(s->dpi.mask & (*(u32*)(xprt+s->dpi.offset)^s->dpi.key))
#if RSVP_DST_LEN == 4
                    && dst[0] == s->dst[0]
                    && dst[1] == s->dst[1]
                    && dst[2] == s->dst[2]
#endif
                    && tunnelid == s->tunnelid) {
 
                        for (f = s->ht[h2]; f; f = f->next) {
                                if (src[RSVP_DST_LEN-1] == f->src[RSVP_DST_LEN-1] &&
                                    !(f->spi.mask & (*(u32*)(xprt+f->spi.offset)^f->spi.key))
#if RSVP_DST_LEN == 4
                                    && src[0] == f->src[0]
                                    && src[1] == f->src[1]
                                    && src[2] == f->src[2]
#endif
                                    ) {
                                        *res = f->res;
 
                                        RSVP_POLICE();
 
matched:
                                        if (f->tunnelhdr == 0)
                                                return 0;
 
                                        tunnelid = f->res.classid;
                                        nhptr = (void*)(xprt + f->tunnelhdr - sizeof(*nhptr));
                                        goto restart;
                                }
                        }
 
                        /* And wildcard bucket... */
                        for (f = s->ht[16]; f; f = f->next) {
                                *res = f->res;
                                RSVP_POLICE();
                                goto matched;
                        }
                        return -1;
                }
        }
        return -1;
}
 
static unsigned long rsvp_get(struct tcf_proto *tp, u32 handle)
{
        struct rsvp_session **sht = ((struct rsvp_head*)tp->root)->ht;
        struct rsvp_session *s;
        struct rsvp_filter *f;
        unsigned h1 = handle&0xFF;
        unsigned h2 = (handle>>8)&0xFF;
 
        if (h2 > 16)
                return 0;
 
        for (s = sht[h1]; s; s = s->next) {
                for (f = s->ht[h2]; f; f = f->next) {
                        if (f->handle == handle)
                                return (unsigned long)f;
                }
        }
        return 0;
}
 
static void rsvp_put(struct tcf_proto *tp, unsigned long f)
{
}
 
static int rsvp_init(struct tcf_proto *tp)
{
        struct rsvp_head *data;
 
        MOD_INC_USE_COUNT;
        data = kmalloc(sizeof(struct rsvp_head), GFP_KERNEL);
        if (data) {
                memset(data, 0, sizeof(struct rsvp_head));
                tp->root = data;
                return 0;
        }
        MOD_DEC_USE_COUNT;
        return -ENOBUFS;
}
 
static void rsvp_destroy(struct tcf_proto *tp)
{
        struct rsvp_head *data = xchg(&tp->root, NULL);
        struct rsvp_session **sht;
        int h1, h2;
 
        if (data == NULL)
                return;
 
        sht = data->ht;
 
        for (h1=0; h1<256; h1++) {
                struct rsvp_session *s;
 
                while ((s = sht[h1]) != NULL) {
                        sht[h1] = s->next;
 
                        for (h2=0; h2<=16; h2++) {
                                struct rsvp_filter *f;
 
                                while ((f = s->ht[h2]) != NULL) {
                                        unsigned long cl;
 
                                        s->ht[h2] = f->next;
                                        if ((cl = __cls_set_class(&f->res.class, 0)) != 0)
                                                tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
#ifdef CONFIG_NET_CLS_POLICE
                                        tcf_police_release(f->police);
#endif
                                        kfree(f);
                                }
                        }
                        kfree(s);
                }
        }
        kfree(data);
        MOD_DEC_USE_COUNT;
}
 
static int rsvp_delete(struct tcf_proto *tp, unsigned long arg)
{
        struct rsvp_filter **fp, *f = (struct rsvp_filter*)arg;
        unsigned h = f->handle;
        struct rsvp_session **sp;
        struct rsvp_session *s = f->sess;
        int i;
 
        for (fp = &s->ht[(h>>8)&0xFF]; *fp; fp = &(*fp)->next) {
                if (*fp == f) {
                        unsigned long cl;
 
 
                        tcf_tree_lock(tp);
                        *fp = f->next;
                        tcf_tree_unlock(tp);
 
                        if ((cl = cls_set_class(tp, &f->res.class, 0)) != 0)
                                tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
 
#ifdef CONFIG_NET_CLS_POLICE
                        tcf_police_release(f->police);
#endif
 
                        kfree(f);
 
                        /* Strip tree */
 
                        for (i=0; i<=16; i++)
                                if (s->ht[i])
                                        return 0;
 
                        /* OK, session has no flows */
                        for (sp = &((struct rsvp_head*)tp->root)->ht[h&0xFF];
                             *sp; sp = &(*sp)->next) {
                                if (*sp == s) {
                                        tcf_tree_lock(tp);
                                        *sp = s->next;
                                        tcf_tree_unlock(tp);
 
                                        kfree(s);
                                        return 0;
                                }
                        }
 
                        return 0;
                }
        }
        return 0;
}
 
static unsigned gen_handle(struct tcf_proto *tp, unsigned salt)
{
        struct rsvp_head *data = tp->root;
        int i = 0xFFFF;
 
        while (i-- > 0) {
                u32 h;
                if ((data->hgenerator += 0x10000) == 0)
                        data->hgenerator = 0x10000;
                h = data->hgenerator|salt;
                if (rsvp_get(tp, h) == 0)
                        return h;
        }
        return 0;
}
 
static int tunnel_bts(struct rsvp_head *data)
{
        int n = data->tgenerator>>5;
        u32 b = 1<<(data->tgenerator&0x1F);
 
        if (data->tmap[n]&b)
                return 0;
        data->tmap[n] |= b;
        return 1;
}
 
static void tunnel_recycle(struct rsvp_head *data)
{
        struct rsvp_session **sht = data->ht;
        u32 tmap[256/32];
        int h1, h2;
 
        memset(tmap, 0, sizeof(tmap));
 
        for (h1=0; h1<256; h1++) {
                struct rsvp_session *s;
                for (s = sht[h1]; s; s = s->next) {
                        for (h2=0; h2<=16; h2++) {
                                struct rsvp_filter *f;
 
                                for (f = s->ht[h2]; f; f = f->next) {
                                        if (f->tunnelhdr == 0)
                                                continue;
                                        data->tgenerator = f->res.classid;
                                        tunnel_bts(data);
                                }
                        }
                }
        }
 
        memcpy(data->tmap, tmap, sizeof(tmap));
}
 
static u32 gen_tunnel(struct rsvp_head *data)
{
        int i, k;
 
        for (k=0; k<2; k++) {
                for (i=255; i>0; i--) {
                        if (++data->tgenerator == 0)
                                data->tgenerator = 1;
                        if (tunnel_bts(data))
                                return data->tgenerator;
                }
                tunnel_recycle(data);
        }
        return 0;
}
 
static int rsvp_change(struct tcf_proto *tp, unsigned long base,
                       u32 handle,
                       struct rtattr **tca,
                       unsigned long *arg)
{
        struct rsvp_head *data = tp->root;
        struct rsvp_filter *f, **fp;
        struct rsvp_session *s, **sp;
        struct tc_rsvp_pinfo *pinfo = NULL;
        struct rtattr *opt = tca[TCA_OPTIONS-1];
        struct rtattr *tb[TCA_RSVP_MAX];
        unsigned h1, h2;
        u32 *dst;
        int err;
 
        if (opt == NULL)
                return handle ? -EINVAL : 0;
 
        if (rtattr_parse(tb, TCA_RSVP_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)
                return -EINVAL;
 
        if ((f = (struct rsvp_filter*)*arg) != NULL) {
                /* Node exists: adjust only classid */
 
                if (f->handle != handle && handle)
                        return -EINVAL;
                if (tb[TCA_RSVP_CLASSID-1]) {
                        unsigned long cl;
 
                        f->res.classid = *(u32*)RTA_DATA(tb[TCA_RSVP_CLASSID-1]);
                        cl = cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
                        if (cl)
                                tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);
                }
#ifdef CONFIG_NET_CLS_POLICE
                if (tb[TCA_RSVP_POLICE-1]) {
                        struct tcf_police *police = tcf_police_locate(tb[TCA_RSVP_POLICE-1], tca[TCA_RATE-1]);
 
                        tcf_tree_lock(tp);
                        police = xchg(&f->police, police);
                        tcf_tree_unlock(tp);
 
                        tcf_police_release(police);
                }
#endif
                return 0;
        }
 
        /* Now more serious part... */
        if (handle)
                return -EINVAL;
        if (tb[TCA_RSVP_DST-1] == NULL)
                return -EINVAL;
 
        f = kmalloc(sizeof(struct rsvp_filter), GFP_KERNEL);
        if (f == NULL)
                return -ENOBUFS;
 
        memset(f, 0, sizeof(*f));
        h2 = 16;
        if (tb[TCA_RSVP_SRC-1]) {
                err = -EINVAL;
                if (RTA_PAYLOAD(tb[TCA_RSVP_SRC-1]) != sizeof(f->src))
                        goto errout;
                memcpy(f->src, RTA_DATA(tb[TCA_RSVP_SRC-1]), sizeof(f->src));
                h2 = hash_src(f->src);
        }
        if (tb[TCA_RSVP_PINFO-1]) {
                err = -EINVAL;
                if (RTA_PAYLOAD(tb[TCA_RSVP_PINFO-1]) < sizeof(struct tc_rsvp_pinfo))
                        goto errout;
                pinfo = RTA_DATA(tb[TCA_RSVP_PINFO-1]);
                f->spi = pinfo->spi;
                f->tunnelhdr = pinfo->tunnelhdr;
        }
        if (tb[TCA_RSVP_CLASSID-1]) {
                err = -EINVAL;
                if (RTA_PAYLOAD(tb[TCA_RSVP_CLASSID-1]) != 4)
                        goto errout;
                f->res.classid = *(u32*)RTA_DATA(tb[TCA_RSVP_CLASSID-1]);
        }
 
        err = -EINVAL;
        if (RTA_PAYLOAD(tb[TCA_RSVP_DST-1]) != sizeof(f->src))
                goto errout;
        dst = RTA_DATA(tb[TCA_RSVP_DST-1]);
        h1 = hash_dst(dst, pinfo ? pinfo->protocol : 0, pinfo ? pinfo->tunnelid : 0);
 
        err = -ENOMEM;
        if ((f->handle = gen_handle(tp, h1 | (h2<<8))) == 0)
                goto errout;
 
        if (f->tunnelhdr) {
                err = -EINVAL;
                if (f->res.classid > 255)
                        goto errout;
 
                err = -ENOMEM;
                if (f->res.classid == 0 &&
                    (f->res.classid = gen_tunnel(data)) == 0)
                        goto errout;
        }
 
        for (sp = &data->ht[h1]; (s=*sp) != NULL; sp = &s->next) {
                if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&
                    pinfo && pinfo->protocol == s->protocol &&
                    memcmp(&pinfo->dpi, &s->dpi, sizeof(s->dpi)) == 0
#if RSVP_DST_LEN == 4
                    && dst[0] == s->dst[0]
                    && dst[1] == s->dst[1]
                    && dst[2] == s->dst[2]
#endif
                    && pinfo->tunnelid == s->tunnelid) {
 
insert:
                        /* OK, we found appropriate session */
 
                        fp = &s->ht[h2];
 
                        f->sess = s;
                        if (f->tunnelhdr == 0)
                                cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));
#ifdef CONFIG_NET_CLS_POLICE
                        if (tb[TCA_RSVP_POLICE-1])
                                f->police = tcf_police_locate(tb[TCA_RSVP_POLICE-1], tca[TCA_RATE-1]);
#endif
 
                        for (fp = &s->ht[h2]; *fp; fp = &(*fp)->next)
                                if (((*fp)->spi.mask&f->spi.mask) != f->spi.mask)
                                        break;
                        f->next = *fp;
                        wmb();
                        *fp = f;
 
                        *arg = (unsigned long)f;
                        return 0;
                }
        }
 
        /* No session found. Create new one. */
 
        err = -ENOBUFS;
        s = kmalloc(sizeof(struct rsvp_session), GFP_KERNEL);
        if (s == NULL)
                goto errout;
        memset(s, 0, sizeof(*s));
        memcpy(s->dst, dst, sizeof(s->dst));
 
        if (pinfo) {
                s->dpi = pinfo->dpi;
                s->protocol = pinfo->protocol;
                s->tunnelid = pinfo->tunnelid;
        }
        for (sp = &data->ht[h1]; *sp; sp = &(*sp)->next) {
                if (((*sp)->dpi.mask&s->dpi.mask) != s->dpi.mask)
                        break;
        }
        s->next = *sp;
        wmb();
        *sp = s;
 
        goto insert;
 
errout:
        if (f)
                kfree(f);
        return err;
}
 
static void rsvp_walk(struct tcf_proto *tp, struct tcf_walker *arg)
{
        struct rsvp_head *head = tp->root;
        unsigned h, h1;
 
        if (arg->stop)
                return;
 
        for (h = 0; h < 256; h++) {
                struct rsvp_session *s;
 
                for (s = head->ht[h]; s; s = s->next) {
                        for (h1 = 0; h1 <= 16; h1++) {
                                struct rsvp_filter *f;
 
                                for (f = s->ht[h1]; f; f = f->next) {
                                        if (arg->count < arg->skip) {
                                                arg->count++;
                                                continue;
                                        }
                                        if (arg->fn(tp, (unsigned long)f, arg) < 0) {
                                                arg->stop = 1;
                                                break;
                                        }
                                        arg->count++;
                                }
                        }
                }
        }
}
 
static int rsvp_dump(struct tcf_proto *tp, unsigned long fh,
                     struct sk_buff *skb, struct tcmsg *t)
{
        struct rsvp_filter *f = (struct rsvp_filter*)fh;
        struct rsvp_session *s;
        unsigned char    *b = skb->tail;
        struct rtattr *rta;
        struct tc_rsvp_pinfo pinfo;
 
        if (f == NULL)
                return skb->len;
        s = f->sess;
 
        t->tcm_handle = f->handle;
 
 
        rta = (struct rtattr*)b;
        RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 
        RTA_PUT(skb, TCA_RSVP_DST, sizeof(s->dst), &s->dst);
        pinfo.dpi = s->dpi;
        pinfo.spi = f->spi;
        pinfo.protocol = s->protocol;
        pinfo.tunnelid = s->tunnelid;
        pinfo.tunnelhdr = f->tunnelhdr;
        RTA_PUT(skb, TCA_RSVP_PINFO, sizeof(pinfo), &pinfo);
        if (f->res.classid)
                RTA_PUT(skb, TCA_RSVP_CLASSID, 4, &f->res.classid);
        if (((f->handle>>8)&0xFF) != 16)
                RTA_PUT(skb, TCA_RSVP_SRC, sizeof(f->src), f->src);
#ifdef CONFIG_NET_CLS_POLICE
        if (f->police) {
                struct rtattr * p_rta = (struct rtattr*)skb->tail;
 
                RTA_PUT(skb, TCA_RSVP_POLICE, 0, NULL);
 
                if (tcf_police_dump(skb, f->police) < 0)
                        goto rtattr_failure;
 
                p_rta->rta_len = skb->tail - (u8*)p_rta;
        }
#endif
 
        rta->rta_len = skb->tail - b;
#ifdef CONFIG_NET_CLS_POLICE
        if (f->police) {
                if (qdisc_copy_stats(skb, &f->police->stats))
                        goto rtattr_failure;
        }
#endif
        return skb->len;
 
rtattr_failure:
        skb_trim(skb, b - skb->data);
        return -1;
}
 
struct tcf_proto_ops RSVP_OPS = {
        NULL,
        RSVP_ID,
        rsvp_classify,
        rsvp_init,
        rsvp_destroy,
 
        rsvp_get,
        rsvp_put,
        rsvp_change,
        rsvp_delete,
        rsvp_walk,
        rsvp_dump
};
 
#ifdef MODULE
int init_module(void)
{
        return register_tcf_proto_ops(&RSVP_OPS);
}
 
void cleanup_module(void)
{
        unregister_tcf_proto_ops(&RSVP_OPS);
}
#endif

Browse

Tools

Subversion Repositories or1k

[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [net/] [sched/] [cls_rsvp.h] - Blame information for rev 1774

Line No.	Rev	Author	Line
1	1275	phoenix	`/*`
2			`* net/sched/cls_rsvp.h Template file for RSVPv[46] classifiers.`
3			`*`
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.`
8			`*`
9			`* Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>`
10			`*/`
11
12			`/*`
13			`Comparing to general packet classification problem,`
14			`RSVP needs only sevaral relatively simple rules:`
15
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.`
21
22			`IMPLEMENTATION.`
23
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).`
28
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).`
34
35
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.`
38
39
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`
43			`should be wildcard.`
44
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.`
48
49
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.`
57
58
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)`
63
64
65			`Well, as result, despite its simplicity, we get a pretty`
66			`powerful classification engine. */`
67
68			`#include <linux/config.h>`
69
70			`struct rsvp_head`
71			`{`
72			`u32 tmap[256/32];`
73			`u32 hgenerator;`
74			`u8 tgenerator;`
75			`struct rsvp_session *ht[256];`
76			`};`
77
78			`struct rsvp_session`
79			`{`
80			`struct rsvp_session *next;`
81			`u32 dst[RSVP_DST_LEN];`
82			`struct tc_rsvp_gpi dpi;`
83			`u8 protocol;`
84			`u8 tunnelid;`
85			`/* 16 (src,sport) hash slots, and one wildcard source slot */`
86			`struct rsvp_filter *ht[16+1];`
87			`};`
88
89
90			`struct rsvp_filter`
91			`{`
92			`struct rsvp_filter *next;`
93			`u32 src[RSVP_DST_LEN];`
94			`struct tc_rsvp_gpi spi;`
95			`u8 tunnelhdr;`
96
97			`struct tcf_result res;`
98			`#ifdef CONFIG_NET_CLS_POLICE`
99			`struct tcf_police *police;`
100			`#endif`
101
102			`u32 handle;`
103			`struct rsvp_session *sess;`
104			`};`
105
106			`static __inline__ unsigned hash_dst(u32 *dst, u8 protocol, u8 tunnelid)`
107			`{`
108			`unsigned h = dst[RSVP_DST_LEN-1];`
109			`h ^= h>>16;`
110			`h ^= h>>8;`
111			`return (h ^ protocol ^ tunnelid) & 0xFF;`
112			`}`
113
114			`static __inline__ unsigned hash_src(u32 *src)`
115			`{`
116			`unsigned h = src[RSVP_DST_LEN-1];`
117			`h ^= h>>16;`
118			`h ^= h>>8;`
119			`h ^= h>>4;`
120			`return h & 0xF;`
121			`}`
122
123			`#ifdef CONFIG_NET_CLS_POLICE`
124			`#define RSVP_POLICE() \`
125			`if (f->police) { \`
126			`int pol_res = tcf_police(skb, f->police); \`
127			`if (pol_res < 0) continue; \`
128			`if (pol_res) return pol_res; \`
129			`}`
130			`#else`
131			`#define RSVP_POLICE()`
132			`#endif`
133
134
135			`static int rsvp_classify(struct sk_buff skb, struct tcf_proto tp,`
136			`struct tcf_result *res)`
137			`{`
138			`struct rsvp_session *sht = ((struct rsvp_head)tp->root)->ht;`
139			`struct rsvp_session *s;`
140			`struct rsvp_filter *f;`
141			`unsigned h1, h2;`
142			`u32 dst, src;`
143			`u8 protocol;`
144			`u8 tunnelid = 0;`
145			`u8 *xprt;`
146			`#if RSVP_DST_LEN == 4`
147			`struct ipv6hdr *nhptr = skb->nh.ipv6h;`
148			`#else`
149			`struct iphdr *nhptr = skb->nh.iph;`
150			`#endif`
151
152			`restart:`
153
154			`#if RSVP_DST_LEN == 4`
155			`src = &nhptr->saddr.s6_addr32[0];`
156			`dst = &nhptr->daddr.s6_addr32[0];`
157			`protocol = nhptr->nexthdr;`
158			`xprt = ((u8*)nhptr) + sizeof(struct ipv6hdr);`
159			`#else`
160			`src = &nhptr->saddr;`
161			`dst = &nhptr->daddr;`
162			`protocol = nhptr->protocol;`
163			`xprt = ((u8*)nhptr) + (nhptr->ihl<<2);`
164			`if (nhptr->frag_off&__constant_htons(IP_MF\|IP_OFFSET))`
165			`return -1;`
166			`#endif`
167
168			`h1 = hash_dst(dst, protocol, tunnelid);`
169			`h2 = hash_src(src);`
170
171			`for (s = sht[h1]; s; s = s->next) {`
172			`if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&`
173			`protocol == s->protocol &&`
174			`!(s->dpi.mask & ((u32)(xprt+s->dpi.offset)^s->dpi.key))`
175			`#if RSVP_DST_LEN == 4`
176			`&& dst[0] == s->dst[0]`
177			`&& dst[1] == s->dst[1]`
178			`&& dst[2] == s->dst[2]`
179			`#endif`
180			`&& tunnelid == s->tunnelid) {`
181
182			`for (f = s->ht[h2]; f; f = f->next) {`
183			`if (src[RSVP_DST_LEN-1] == f->src[RSVP_DST_LEN-1] &&`
184			`!(f->spi.mask & ((u32)(xprt+f->spi.offset)^f->spi.key))`
185			`#if RSVP_DST_LEN == 4`
186			`&& src[0] == f->src[0]`
187			`&& src[1] == f->src[1]`
188			`&& src[2] == f->src[2]`
189			`#endif`
190			`) {`
191			`*res = f->res;`
192
193			`RSVP_POLICE();`
194
195			`matched:`
196			`if (f->tunnelhdr == 0)`
197			`return 0;`
198
199			`tunnelid = f->res.classid;`
200			`nhptr = (void)(xprt + f->tunnelhdr - sizeof(nhptr));`
201			`goto restart;`
202			`}`
203			`}`
204
205			`/* And wildcard bucket... */`
206			`for (f = s->ht[16]; f; f = f->next) {`
207			`*res = f->res;`
208			`RSVP_POLICE();`
209			`goto matched;`
210			`}`
211			`return -1;`
212			`}`
213			`}`
214			`return -1;`
215			`}`
216
217			`static unsigned long rsvp_get(struct tcf_proto *tp, u32 handle)`
218			`{`
219			`struct rsvp_session *sht = ((struct rsvp_head)tp->root)->ht;`
220			`struct rsvp_session *s;`
221			`struct rsvp_filter *f;`
222			`unsigned h1 = handle&0xFF;`
223			`unsigned h2 = (handle>>8)&0xFF;`
224
225			`if (h2 > 16)`
226			`return 0;`
227
228			`for (s = sht[h1]; s; s = s->next) {`
229			`for (f = s->ht[h2]; f; f = f->next) {`
230			`if (f->handle == handle)`
231			`return (unsigned long)f;`
232			`}`
233			`}`
234			`return 0;`
235			`}`
236
237			`static void rsvp_put(struct tcf_proto *tp, unsigned long f)`
238			`{`
239			`}`
240
241			`static int rsvp_init(struct tcf_proto *tp)`
242			`{`
243			`struct rsvp_head *data;`
244
245			`MOD_INC_USE_COUNT;`
246			`data = kmalloc(sizeof(struct rsvp_head), GFP_KERNEL);`
247			`if (data) {`
248			`memset(data, 0, sizeof(struct rsvp_head));`
249			`tp->root = data;`
250			`return 0;`
251			`}`
252			`MOD_DEC_USE_COUNT;`
253			`return -ENOBUFS;`
254			`}`
255
256			`static void rsvp_destroy(struct tcf_proto *tp)`
257			`{`
258			`struct rsvp_head *data = xchg(&tp->root, NULL);`
259			`struct rsvp_session **sht;`
260			`int h1, h2;`
261
262			`if (data == NULL)`
263			`return;`
264
265			`sht = data->ht;`
266
267			`for (h1=0; h1<256; h1++) {`
268			`struct rsvp_session *s;`
269
270			`while ((s = sht[h1]) != NULL) {`
271			`sht[h1] = s->next;`
272
273			`for (h2=0; h2<=16; h2++) {`
274			`struct rsvp_filter *f;`
275
276			`while ((f = s->ht[h2]) != NULL) {`
277			`unsigned long cl;`
278
279			`s->ht[h2] = f->next;`
280			`if ((cl = __cls_set_class(&f->res.class, 0)) != 0)`
281			`tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);`
282			`#ifdef CONFIG_NET_CLS_POLICE`
283			`tcf_police_release(f->police);`
284			`#endif`
285			`kfree(f);`
286			`}`
287			`}`
288			`kfree(s);`
289			`}`
290			`}`
291			`kfree(data);`
292			`MOD_DEC_USE_COUNT;`
293			`}`
294
295			`static int rsvp_delete(struct tcf_proto *tp, unsigned long arg)`
296			`{`
297			`struct rsvp_filter *fp, f = (struct rsvp_filter*)arg;`
298			`unsigned h = f->handle;`
299			`struct rsvp_session **sp;`
300			`struct rsvp_session *s = f->sess;`
301			`int i;`
302
303			`for (fp = &s->ht[(h>>8)&0xFF]; fp; fp = &(fp)->next) {`
304			`if (*fp == f) {`
305			`unsigned long cl;`
306
307
308			`tcf_tree_lock(tp);`
309			`*fp = f->next;`
310			`tcf_tree_unlock(tp);`
311
312			`if ((cl = cls_set_class(tp, &f->res.class, 0)) != 0)`
313			`tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);`
314
315			`#ifdef CONFIG_NET_CLS_POLICE`
316			`tcf_police_release(f->police);`
317			`#endif`
318
319			`kfree(f);`
320
321			`/* Strip tree */`
322
323			`for (i=0; i<=16; i++)`
324			`if (s->ht[i])`
325			`return 0;`
326
327			`/* OK, session has no flows */`
328			`for (sp = &((struct rsvp_head*)tp->root)->ht[h&0xFF];`
329			`sp; sp = &(sp)->next) {`
330			`if (*sp == s) {`
331			`tcf_tree_lock(tp);`
332			`*sp = s->next;`
333			`tcf_tree_unlock(tp);`
334
335			`kfree(s);`
336			`return 0;`
337			`}`
338			`}`
339
340			`return 0;`
341			`}`
342			`}`
343			`return 0;`
344			`}`
345
346			`static unsigned gen_handle(struct tcf_proto *tp, unsigned salt)`
347			`{`
348			`struct rsvp_head *data = tp->root;`
349			`int i = 0xFFFF;`
350
351			`while (i-- > 0) {`
352			`u32 h;`
353			`if ((data->hgenerator += 0x10000) == 0)`
354			`data->hgenerator = 0x10000;`
355			`h = data->hgenerator\|salt;`
356			`if (rsvp_get(tp, h) == 0)`
357			`return h;`
358			`}`
359			`return 0;`
360			`}`
361
362			`static int tunnel_bts(struct rsvp_head *data)`
363			`{`
364			`int n = data->tgenerator>>5;`
365			`u32 b = 1<<(data->tgenerator&0x1F);`
366
367			`if (data->tmap[n]&b)`
368			`return 0;`
369			`data->tmap[n] \|= b;`
370			`return 1;`
371			`}`
372
373			`static void tunnel_recycle(struct rsvp_head *data)`
374			`{`
375			`struct rsvp_session **sht = data->ht;`
376			`u32 tmap[256/32];`
377			`int h1, h2;`
378
379			`memset(tmap, 0, sizeof(tmap));`
380
381			`for (h1=0; h1<256; h1++) {`
382			`struct rsvp_session *s;`
383			`for (s = sht[h1]; s; s = s->next) {`
384			`for (h2=0; h2<=16; h2++) {`
385			`struct rsvp_filter *f;`
386
387			`for (f = s->ht[h2]; f; f = f->next) {`
388			`if (f->tunnelhdr == 0)`
389			`continue;`
390			`data->tgenerator = f->res.classid;`
391			`tunnel_bts(data);`
392			`}`
393			`}`
394			`}`
395			`}`
396
397			`memcpy(data->tmap, tmap, sizeof(tmap));`
398			`}`
399
400			`static u32 gen_tunnel(struct rsvp_head *data)`
401			`{`
402			`int i, k;`
403
404			`for (k=0; k<2; k++) {`
405			`for (i=255; i>0; i--) {`
406			`if (++data->tgenerator == 0)`
407			`data->tgenerator = 1;`
408			`if (tunnel_bts(data))`
409			`return data->tgenerator;`
410			`}`
411			`tunnel_recycle(data);`
412			`}`
413			`return 0;`
414			`}`
415
416			`static int rsvp_change(struct tcf_proto *tp, unsigned long base,`
417			`u32 handle,`
418			`struct rtattr **tca,`
419			`unsigned long *arg)`
420			`{`
421			`struct rsvp_head *data = tp->root;`
422			`struct rsvp_filter f, *fp;`
423			`struct rsvp_session s, *sp;`
424			`struct tc_rsvp_pinfo *pinfo = NULL;`
425			`struct rtattr *opt = tca[TCA_OPTIONS-1];`
426			`struct rtattr *tb[TCA_RSVP_MAX];`
427			`unsigned h1, h2;`
428			`u32 *dst;`
429			`int err;`
430
431			`if (opt == NULL)`
432			`return handle ? -EINVAL : 0;`
433
434			`if (rtattr_parse(tb, TCA_RSVP_MAX, RTA_DATA(opt), RTA_PAYLOAD(opt)) < 0)`
435			`return -EINVAL;`
436
437			`if ((f = (struct rsvp_filter)arg) != NULL) {`
438			`/* Node exists: adjust only classid */`
439
440			`if (f->handle != handle && handle)`
441			`return -EINVAL;`
442			`if (tb[TCA_RSVP_CLASSID-1]) {`
443			`unsigned long cl;`
444
445			`f->res.classid = (u32)RTA_DATA(tb[TCA_RSVP_CLASSID-1]);`
446			`cl = cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));`
447			`if (cl)`
448			`tp->q->ops->cl_ops->unbind_tcf(tp->q, cl);`
449			`}`
450			`#ifdef CONFIG_NET_CLS_POLICE`
451			`if (tb[TCA_RSVP_POLICE-1]) {`
452			`struct tcf_police *police = tcf_police_locate(tb[TCA_RSVP_POLICE-1], tca[TCA_RATE-1]);`
453
454			`tcf_tree_lock(tp);`
455			`police = xchg(&f->police, police);`
456			`tcf_tree_unlock(tp);`
457
458			`tcf_police_release(police);`
459			`}`
460			`#endif`
461			`return 0;`
462			`}`
463
464			`/* Now more serious part... */`
465			`if (handle)`
466			`return -EINVAL;`
467			`if (tb[TCA_RSVP_DST-1] == NULL)`
468			`return -EINVAL;`
469
470			`f = kmalloc(sizeof(struct rsvp_filter), GFP_KERNEL);`
471			`if (f == NULL)`
472			`return -ENOBUFS;`
473
474			`memset(f, 0, sizeof(*f));`
475			`h2 = 16;`
476			`if (tb[TCA_RSVP_SRC-1]) {`
477			`err = -EINVAL;`
478			`if (RTA_PAYLOAD(tb[TCA_RSVP_SRC-1]) != sizeof(f->src))`
479			`goto errout;`
480			`memcpy(f->src, RTA_DATA(tb[TCA_RSVP_SRC-1]), sizeof(f->src));`
481			`h2 = hash_src(f->src);`
482			`}`
483			`if (tb[TCA_RSVP_PINFO-1]) {`
484			`err = -EINVAL;`
485			`if (RTA_PAYLOAD(tb[TCA_RSVP_PINFO-1]) < sizeof(struct tc_rsvp_pinfo))`
486			`goto errout;`
487			`pinfo = RTA_DATA(tb[TCA_RSVP_PINFO-1]);`
488			`f->spi = pinfo->spi;`
489			`f->tunnelhdr = pinfo->tunnelhdr;`
490			`}`
491			`if (tb[TCA_RSVP_CLASSID-1]) {`
492			`err = -EINVAL;`
493			`if (RTA_PAYLOAD(tb[TCA_RSVP_CLASSID-1]) != 4)`
494			`goto errout;`
495			`f->res.classid = (u32)RTA_DATA(tb[TCA_RSVP_CLASSID-1]);`
496			`}`
497
498			`err = -EINVAL;`
499			`if (RTA_PAYLOAD(tb[TCA_RSVP_DST-1]) != sizeof(f->src))`
500			`goto errout;`
501			`dst = RTA_DATA(tb[TCA_RSVP_DST-1]);`
502			`h1 = hash_dst(dst, pinfo ? pinfo->protocol : 0, pinfo ? pinfo->tunnelid : 0);`
503
504			`err = -ENOMEM;`
505			`if ((f->handle = gen_handle(tp, h1 \| (h2<<8))) == 0)`
506			`goto errout;`
507
508			`if (f->tunnelhdr) {`
509			`err = -EINVAL;`
510			`if (f->res.classid > 255)`
511			`goto errout;`
512
513			`err = -ENOMEM;`
514			`if (f->res.classid == 0 &&`
515			`(f->res.classid = gen_tunnel(data)) == 0)`
516			`goto errout;`
517			`}`
518
519			`for (sp = &data->ht[h1]; (s=*sp) != NULL; sp = &s->next) {`
520			`if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&`
521			`pinfo && pinfo->protocol == s->protocol &&`
522			`memcmp(&pinfo->dpi, &s->dpi, sizeof(s->dpi)) == 0`
523			`#if RSVP_DST_LEN == 4`
524			`&& dst[0] == s->dst[0]`
525			`&& dst[1] == s->dst[1]`
526			`&& dst[2] == s->dst[2]`
527			`#endif`
528			`&& pinfo->tunnelid == s->tunnelid) {`
529
530			`insert:`
531			`/* OK, we found appropriate session */`
532
533			`fp = &s->ht[h2];`
534
535			`f->sess = s;`
536			`if (f->tunnelhdr == 0)`
537			`cls_set_class(tp, &f->res.class, tp->q->ops->cl_ops->bind_tcf(tp->q, base, f->res.classid));`
538			`#ifdef CONFIG_NET_CLS_POLICE`
539			`if (tb[TCA_RSVP_POLICE-1])`
540			`f->police = tcf_police_locate(tb[TCA_RSVP_POLICE-1], tca[TCA_RATE-1]);`
541			`#endif`
542
543			`for (fp = &s->ht[h2]; fp; fp = &(fp)->next)`
544			`if (((*fp)->spi.mask&f->spi.mask) != f->spi.mask)`
545			`break;`
546			`f->next = *fp;`
547			`wmb();`
548			`*fp = f;`
549
550			`*arg = (unsigned long)f;`
551			`return 0;`
552			`}`
553			`}`
554
555			`/* No session found. Create new one. */`
556
557			`err = -ENOBUFS;`
558			`s = kmalloc(sizeof(struct rsvp_session), GFP_KERNEL);`
559			`if (s == NULL)`
560			`goto errout;`
561			`memset(s, 0, sizeof(*s));`
562			`memcpy(s->dst, dst, sizeof(s->dst));`
563
564			`if (pinfo) {`
565			`s->dpi = pinfo->dpi;`
566			`s->protocol = pinfo->protocol;`
567			`s->tunnelid = pinfo->tunnelid;`
568			`}`
569			`for (sp = &data->ht[h1]; sp; sp = &(sp)->next) {`
570			`if (((*sp)->dpi.mask&s->dpi.mask) != s->dpi.mask)`
571			`break;`
572			`}`
573			`s->next = *sp;`
574			`wmb();`
575			`*sp = s;`
576
577			`goto insert;`
578
579			`errout:`
580			`if (f)`
581			`kfree(f);`
582			`return err;`
583			`}`
584
585			`static void rsvp_walk(struct tcf_proto tp, struct tcf_walker arg)`
586			`{`
587			`struct rsvp_head *head = tp->root;`
588			`unsigned h, h1;`
589
590			`if (arg->stop)`
591			`return;`
592
593			`for (h = 0; h < 256; h++) {`
594			`struct rsvp_session *s;`
595
596			`for (s = head->ht[h]; s; s = s->next) {`
597			`for (h1 = 0; h1 <= 16; h1++) {`
598			`struct rsvp_filter *f;`
599
600			`for (f = s->ht[h1]; f; f = f->next) {`
601			`if (arg->count < arg->skip) {`
602			`arg->count++;`
603			`continue;`
604			`}`
605			`if (arg->fn(tp, (unsigned long)f, arg) < 0) {`
606			`arg->stop = 1;`
607			`break;`
608			`}`
609			`arg->count++;`
610			`}`
611			`}`
612			`}`
613			`}`
614			`}`
615
616			`static int rsvp_dump(struct tcf_proto *tp, unsigned long fh,`
617			`struct sk_buff skb, struct tcmsg t)`
618			`{`
619			`struct rsvp_filter f = (struct rsvp_filter)fh;`
620			`struct rsvp_session *s;`
621			`unsigned char *b = skb->tail;`
622			`struct rtattr *rta;`
623			`struct tc_rsvp_pinfo pinfo;`
624
625			`if (f == NULL)`
626			`return skb->len;`
627			`s = f->sess;`
628
629			`t->tcm_handle = f->handle;`
630
631
632			`rta = (struct rtattr*)b;`
633			`RTA_PUT(skb, TCA_OPTIONS, 0, NULL);`
634
635			`RTA_PUT(skb, TCA_RSVP_DST, sizeof(s->dst), &s->dst);`
636			`pinfo.dpi = s->dpi;`
637			`pinfo.spi = f->spi;`
638			`pinfo.protocol = s->protocol;`
639			`pinfo.tunnelid = s->tunnelid;`
640			`pinfo.tunnelhdr = f->tunnelhdr;`
641			`RTA_PUT(skb, TCA_RSVP_PINFO, sizeof(pinfo), &pinfo);`
642			`if (f->res.classid)`
643			`RTA_PUT(skb, TCA_RSVP_CLASSID, 4, &f->res.classid);`
644			`if (((f->handle>>8)&0xFF) != 16)`
645			`RTA_PUT(skb, TCA_RSVP_SRC, sizeof(f->src), f->src);`
646			`#ifdef CONFIG_NET_CLS_POLICE`
647			`if (f->police) {`
648			`struct rtattr * p_rta = (struct rtattr*)skb->tail;`
649
650			`RTA_PUT(skb, TCA_RSVP_POLICE, 0, NULL);`
651
652			`if (tcf_police_dump(skb, f->police) < 0)`
653			`goto rtattr_failure;`
654
655			`p_rta->rta_len = skb->tail - (u8*)p_rta;`
656			`}`
657			`#endif`
658
659			`rta->rta_len = skb->tail - b;`
660			`#ifdef CONFIG_NET_CLS_POLICE`
661			`if (f->police) {`
662			`if (qdisc_copy_stats(skb, &f->police->stats))`
663			`goto rtattr_failure;`
664			`}`
665			`#endif`
666			`return skb->len;`
667
668			`rtattr_failure:`
669			`skb_trim(skb, b - skb->data);`
670			`return -1;`
671			`}`
672
673			`struct tcf_proto_ops RSVP_OPS = {`
674			`NULL,`
675			`RSVP_ID,`
676			`rsvp_classify,`
677			`rsvp_init,`
678			`rsvp_destroy,`
679
680			`rsvp_get,`
681			`rsvp_put,`
682			`rsvp_change,`
683			`rsvp_delete,`
684			`rsvp_walk,`
685			`rsvp_dump`
686			`};`
687
688			`#ifdef MODULE`
689			`int init_module(void)`
690			`{`
691			`return register_tcf_proto_ops(&RSVP_OPS);`
692			`}`
693
694			`void cleanup_module(void)`
695			`{`
696			`unregister_tcf_proto_ops(&RSVP_OPS);`
697			`}`
698			`#endif`