/* * net/sched/pedit.c Generic packet editor * * 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: Jamal Hadi Salim (2002-4) */ #include <asm/uaccess.h> #include <asm/system.h> #include <asm/bitops.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/netdevice.h> #include <linux/skbuff.h> #include <linux/rtnetlink.h> #include <linux/module.h> #include <linux/init.h> #include <linux/proc_fs.h> #include <net/sock.h> #include <net/pkt_sched.h> #include <linux/tc_act/tc_pedit.h> #include <net/tc_act/tc_pedit.h> #define PEDIT_DEB 1 /* use generic hash table */ #define MY_TAB_SIZE 16 #define MY_TAB_MASK 15 static u32 idx_gen; static struct tcf_pedit *tcf_pedit_ht[MY_TAB_SIZE]; static DEFINE_RWLOCK(pedit_lock); #define tcf_st tcf_pedit #define tc_st tc_pedit #define tcf_t_lock pedit_lock #define tcf_ht tcf_pedit_ht #define CONFIG_NET_ACT_INIT 1 #include <net/pkt_act.h> static int tcf_pedit_init(struct rtattr *rta, struct rtattr *est, struct tc_action *a, int ovr, int bind) { struct rtattr *tb[TCA_PEDIT_MAX]; struct tc_pedit *parm; int ret = 0; struct tcf_pedit *p; struct tc_pedit_key *keys = NULL; int ksize; if (rta == NULL || rtattr_parse_nested(tb, TCA_PEDIT_MAX, rta) < 0) return -EINVAL; if (tb[TCA_PEDIT_PARMS - 1] == NULL || RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm)) return -EINVAL; parm = RTA_DATA(tb[TCA_PEDIT_PARMS-1]); ksize = parm->nkeys * sizeof(struct tc_pedit_key); if (RTA_PAYLOAD(tb[TCA_PEDIT_PARMS-1]) < sizeof(*parm) + ksize) return -EINVAL; p = tcf_hash_check(parm->index, a, ovr, bind); if (p == NULL) { if (!parm->nkeys) return -EINVAL; p = tcf_hash_create(parm->index, est, a, sizeof(*p), ovr, bind); if (p == NULL) return -ENOMEM; keys = kmalloc(ksize, GFP_KERNEL); if (keys == NULL) { kfree(p); return -ENOMEM; } ret = ACT_P_CREATED; } else { if (!ovr) { tcf_hash_release(p, bind); return -EEXIST; } if (p->nkeys && p->nkeys != parm->nkeys) { keys = kmalloc(ksize, GFP_KERNEL); if (keys == NULL) return -ENOMEM; } } spin_lock_bh(&p->lock); p->flags = parm->flags; p->action = parm->action; if (keys) { kfree(p->keys); p->keys = keys; p->nkeys = parm->nkeys; } memcpy(p->keys, parm->keys, ksize); spin_unlock_bh(&p->lock); if (ret == ACT_P_CREATED) tcf_hash_insert(p); return ret; } static int tcf_pedit_cleanup(struct tc_action *a, int bind) { struct tcf_pedit *p = PRIV(a, pedit); if (p != NULL) { struct tc_pedit_key *keys = p->keys; if (tcf_hash_release(p, bind)) { kfree(keys); return 1; } } return 0; } static int tcf_pedit(struct sk_buff *skb, struct tc_action *a, struct tcf_result *res) { struct tcf_pedit *p = PRIV(a, pedit); int i, munged = 0; u8 *pptr; if (!(skb->tc_verd & TC_OK2MUNGE)) { /* should we set skb->cloned? */ if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) { return p->action; } } pptr = skb->nh.raw; spin_lock(&p->lock); p->tm.lastuse = jiffies; if (p->nkeys > 0) { struct tc_pedit_key *tkey = p->keys; for (i = p->nkeys; i > 0; i--, tkey++) { u32 *ptr; int offset = tkey->off; if (tkey->offmask) { if (skb->len > tkey->at) { char *j = pptr + tkey->at; offset += ((*j & tkey->offmask) >> tkey->shift); } else { goto bad; } } if (offset % 4) { printk("offset must be on 32 bit boundaries\n"); goto bad; } if (skb->len < 0 || (offset > 0 && offset > skb->len)) { printk("offset %d cant exceed pkt length %d\n", offset, skb->len); goto bad; } ptr = (u32 *)(pptr+offset); /* just do it, baby */ *ptr = ((*ptr & tkey->mask) ^ tkey->val); munged++; } if (munged) skb->tc_verd = SET_TC_MUNGED(skb->tc_verd); goto done; } else { printk("pedit BUG: index %d\n",p->index); } bad: p->qstats.overlimits++; done: p->bstats.bytes += skb->len; p->bstats.packets++; spin_unlock(&p->lock); return p->action; } static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,int bind, int ref) { unsigned char *b = skb->tail; struct tc_pedit *opt; struct tcf_pedit *p = PRIV(a, pedit); struct tcf_t t; int s; s = sizeof(*opt) + p->nkeys * sizeof(struct tc_pedit_key); /* netlink spinlocks held above us - must use ATOMIC */ opt = kmalloc(s, GFP_ATOMIC); if (opt == NULL) return -ENOBUFS; memset(opt, 0, s); memcpy(opt->keys, p->keys, p->nkeys * sizeof(struct tc_pedit_key)); opt->index = p->index; opt->nkeys = p->nkeys; opt->flags = p->flags; opt->action = p->action; opt->refcnt = p->refcnt - ref; opt->bindcnt = p->bindcnt - bind; #ifdef PEDIT_DEB { /* Debug - get rid of later */ int i; struct tc_pedit_key *key = opt->keys; for (i=0; i<opt->nkeys; i++, key++) { printk( "\n key #%d",i); printk( " at %d: val %08x mask %08x", (unsigned int)key->off, (unsigned int)key->val, (unsigned int)key->mask); } } #endif RTA_PUT(skb, TCA_PEDIT_PARMS, s, opt); t.install = jiffies_to_clock_t(jiffies - p->tm.install); t.lastuse = jiffies_to_clock_t(jiffies - p->tm.lastuse); t.expires = jiffies_to_clock_t(p->tm.expires); RTA_PUT(skb, TCA_PEDIT_TM, sizeof(t), &t); kfree(opt); return skb->len; rtattr_failure: skb_trim(skb, b - skb->data); kfree(opt); return -1; } static struct tc_action_ops act_pedit_ops = { .kind = "pedit", .type = TCA_ACT_PEDIT, .capab = TCA_CAP_NONE, .owner = THIS_MODULE, .act = tcf_pedit, .dump = tcf_pedit_dump, .cleanup = tcf_pedit_cleanup, .lookup = tcf_hash_search, .init = tcf_pedit_init, .walk = tcf_generic_walker }; MODULE_AUTHOR("Jamal Hadi Salim(2002-4)"); MODULE_DESCRIPTION("Generic Packet Editor actions"); MODULE_LICENSE("GPL"); static int __init pedit_init_module(void) { return tcf_register_action(&act_pedit_ops); } static void __exit pedit_cleanup_module(void) { tcf_unregister_action(&act_pedit_ops); } module_init(pedit_init_module); module_exit(pedit_cleanup_module);