freebsd-skq/sys/netinet/ip_dummynet.c
luigi 2cf7fe40e7 Kernel support for a dummynet option:
When a pipe or queue has the "noerror" attribute, do not report
drops to the caller (ip_output() and friends).
(2 lines to implement it, 2 lines to document it.)

This will let you simulate losses on the sender side as if they
happened in the middle of the network, i.e. with no explicit feedback
to the sender.

manpage and ipfw2.c changes to follow shortly, together with other
ipfw2 changes.

Requested by: silby
MFC after: 3 days
2002-08-15 16:53:43 +00:00

1972 lines
55 KiB
C

/*
* Copyright (c) 1998-2002 Luigi Rizzo, Universita` di Pisa
* Portions Copyright (c) 2000 Akamba Corp.
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#define DEB(x)
#define DDB(x) x
/*
* This module implements IP dummynet, a bandwidth limiter/delay emulator
* used in conjunction with the ipfw package.
* Description of the data structures used is in ip_dummynet.h
* Here you mainly find the following blocks of code:
* + variable declarations;
* + heap management functions;
* + scheduler and dummynet functions;
* + configuration and initialization.
*
* NOTA BENE: critical sections are protected by splimp()/splx()
* pairs. One would think that splnet() is enough as for most of
* the netinet code, but it is not so because when used with
* bridging, dummynet is invoked at splimp().
*
* Most important Changes:
*
* 011004: KLDable
* 010124: Fixed WF2Q behaviour
* 010122: Fixed spl protection.
* 000601: WF2Q support
* 000106: large rewrite, use heaps to handle very many pipes.
* 980513: initial release
*
* include files marked with XXX are probably not needed
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/proc.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/time.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_fw.h>
#include <netinet/ip_dummynet.h>
#include <netinet/ip_var.h>
#include <netinet/if_ether.h> /* for struct arpcom */
#include <net/bridge.h>
/*
* We keep a private variable for the simulation time, but we could
* probably use an existing one ("softticks" in sys/kern/kern_timer.c)
*/
static dn_key curr_time = 0 ; /* current simulation time */
static int dn_hash_size = 64 ; /* default hash size */
/* statistics on number of queue searches and search steps */
static int searches, search_steps ;
static int pipe_expire = 1 ; /* expire queue if empty */
static int dn_max_ratio = 16 ; /* max queues/buckets ratio */
static int red_lookup_depth = 256; /* RED - default lookup table depth */
static int red_avg_pkt_size = 512; /* RED - default medium packet size */
static int red_max_pkt_size = 1500; /* RED - default max packet size */
/*
* Three heaps contain queues and pipes that the scheduler handles:
*
* ready_heap contains all dn_flow_queue related to fixed-rate pipes.
*
* wfq_ready_heap contains the pipes associated with WF2Q flows
*
* extract_heap contains pipes associated with delay lines.
*
*/
MALLOC_DEFINE(M_DUMMYNET, "dummynet", "dummynet heap");
static struct dn_heap ready_heap, extract_heap, wfq_ready_heap ;
static int heap_init(struct dn_heap *h, int size) ;
static int heap_insert (struct dn_heap *h, dn_key key1, void *p);
static void heap_extract(struct dn_heap *h, void *obj);
static void transmit_event(struct dn_pipe *pipe);
static void ready_event(struct dn_flow_queue *q);
static struct dn_pipe *all_pipes = NULL ; /* list of all pipes */
static struct dn_flow_set *all_flow_sets = NULL ;/* list of all flow_sets */
static struct callout_handle dn_timeout;
#ifdef SYSCTL_NODE
SYSCTL_NODE(_net_inet_ip, OID_AUTO, dummynet,
CTLFLAG_RW, 0, "Dummynet");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, hash_size,
CTLFLAG_RW, &dn_hash_size, 0, "Default hash table size");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, curr_time,
CTLFLAG_RD, &curr_time, 0, "Current tick");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, ready_heap,
CTLFLAG_RD, &ready_heap.size, 0, "Size of ready heap");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, extract_heap,
CTLFLAG_RD, &extract_heap.size, 0, "Size of extract heap");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, searches,
CTLFLAG_RD, &searches, 0, "Number of queue searches");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, search_steps,
CTLFLAG_RD, &search_steps, 0, "Number of queue search steps");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, expire,
CTLFLAG_RW, &pipe_expire, 0, "Expire queue if empty");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, max_chain_len,
CTLFLAG_RW, &dn_max_ratio, 0,
"Max ratio between dynamic queues and buckets");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_lookup_depth,
CTLFLAG_RD, &red_lookup_depth, 0, "Depth of RED lookup table");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_avg_pkt_size,
CTLFLAG_RD, &red_avg_pkt_size, 0, "RED Medium packet size");
SYSCTL_INT(_net_inet_ip_dummynet, OID_AUTO, red_max_pkt_size,
CTLFLAG_RD, &red_max_pkt_size, 0, "RED Max packet size");
#endif
static int config_pipe(struct dn_pipe *p);
static int ip_dn_ctl(struct sockopt *sopt);
static void rt_unref(struct rtentry *);
static void dummynet(void *);
static void dummynet_flush(void);
void dummynet_drain(void);
static ip_dn_io_t dummynet_io;
static void dn_rule_delete(void *);
int if_tx_rdy(struct ifnet *ifp);
static void
rt_unref(struct rtentry *rt)
{
if (rt == NULL)
return ;
if (rt->rt_refcnt <= 0)
printf("-- warning, refcnt now %ld, decreasing\n", rt->rt_refcnt);
RTFREE(rt);
}
/*
* Heap management functions.
*
* In the heap, first node is element 0. Children of i are 2i+1 and 2i+2.
* Some macros help finding parent/children so we can optimize them.
*
* heap_init() is called to expand the heap when needed.
* Increment size in blocks of 16 entries.
* XXX failure to allocate a new element is a pretty bad failure
* as we basically stall a whole queue forever!!
* Returns 1 on error, 0 on success
*/
#define HEAP_FATHER(x) ( ( (x) - 1 ) / 2 )
#define HEAP_LEFT(x) ( 2*(x) + 1 )
#define HEAP_IS_LEFT(x) ( (x) & 1 )
#define HEAP_RIGHT(x) ( 2*(x) + 2 )
#define HEAP_SWAP(a, b, buffer) { buffer = a ; a = b ; b = buffer ; }
#define HEAP_INCREMENT 15
static int
heap_init(struct dn_heap *h, int new_size)
{
struct dn_heap_entry *p;
if (h->size >= new_size ) {
printf("heap_init, Bogus call, have %d want %d\n",
h->size, new_size);
return 0 ;
}
new_size = (new_size + HEAP_INCREMENT ) & ~HEAP_INCREMENT ;
p = malloc(new_size * sizeof(*p), M_DUMMYNET, M_DONTWAIT );
if (p == NULL) {
printf(" heap_init, resize %d failed\n", new_size );
return 1 ; /* error */
}
if (h->size > 0) {
bcopy(h->p, p, h->size * sizeof(*p) );
free(h->p, M_DUMMYNET);
}
h->p = p ;
h->size = new_size ;
return 0 ;
}
/*
* Insert element in heap. Normally, p != NULL, we insert p in
* a new position and bubble up. If p == NULL, then the element is
* already in place, and key is the position where to start the
* bubble-up.
* Returns 1 on failure (cannot allocate new heap entry)
*
* If offset > 0 the position (index, int) of the element in the heap is
* also stored in the element itself at the given offset in bytes.
*/
#define SET_OFFSET(heap, node) \
if (heap->offset > 0) \
*((int *)((char *)(heap->p[node].object) + heap->offset)) = node ;
/*
* RESET_OFFSET is used for sanity checks. It sets offset to an invalid value.
*/
#define RESET_OFFSET(heap, node) \
if (heap->offset > 0) \
*((int *)((char *)(heap->p[node].object) + heap->offset)) = -1 ;
static int
heap_insert(struct dn_heap *h, dn_key key1, void *p)
{
int son = h->elements ;
if (p == NULL) /* data already there, set starting point */
son = key1 ;
else { /* insert new element at the end, possibly resize */
son = h->elements ;
if (son == h->size) /* need resize... */
if (heap_init(h, h->elements+1) )
return 1 ; /* failure... */
h->p[son].object = p ;
h->p[son].key = key1 ;
h->elements++ ;
}
while (son > 0) { /* bubble up */
int father = HEAP_FATHER(son) ;
struct dn_heap_entry tmp ;
if (DN_KEY_LT( h->p[father].key, h->p[son].key ) )
break ; /* found right position */
/* son smaller than father, swap and repeat */
HEAP_SWAP(h->p[son], h->p[father], tmp) ;
SET_OFFSET(h, son);
son = father ;
}
SET_OFFSET(h, son);
return 0 ;
}
/*
* remove top element from heap, or obj if obj != NULL
*/
static void
heap_extract(struct dn_heap *h, void *obj)
{
int child, father, max = h->elements - 1 ;
if (max < 0) {
printf("warning, extract from empty heap 0x%p\n", h);
return ;
}
father = 0 ; /* default: move up smallest child */
if (obj != NULL) { /* extract specific element, index is at offset */
if (h->offset <= 0)
panic("*** heap_extract from middle not supported on this heap!!!\n");
father = *((int *)((char *)obj + h->offset)) ;
if (father < 0 || father >= h->elements) {
printf("dummynet: heap_extract, father %d out of bound 0..%d\n",
father, h->elements);
panic("heap_extract");
}
}
RESET_OFFSET(h, father);
child = HEAP_LEFT(father) ; /* left child */
while (child <= max) { /* valid entry */
if (child != max && DN_KEY_LT(h->p[child+1].key, h->p[child].key) )
child = child+1 ; /* take right child, otherwise left */
h->p[father] = h->p[child] ;
SET_OFFSET(h, father);
father = child ;
child = HEAP_LEFT(child) ; /* left child for next loop */
}
h->elements-- ;
if (father != max) {
/*
* Fill hole with last entry and bubble up, reusing the insert code
*/
h->p[father] = h->p[max] ;
heap_insert(h, father, NULL); /* this one cannot fail */
}
}
#if 0
/*
* change object position and update references
* XXX this one is never used!
*/
static void
heap_move(struct dn_heap *h, dn_key new_key, void *object)
{
int temp;
int i ;
int max = h->elements-1 ;
struct dn_heap_entry buf ;
if (h->offset <= 0)
panic("cannot move items on this heap");
i = *((int *)((char *)object + h->offset));
if (DN_KEY_LT(new_key, h->p[i].key) ) { /* must move up */
h->p[i].key = new_key ;
for (; i>0 && DN_KEY_LT(new_key, h->p[(temp = HEAP_FATHER(i))].key) ;
i = temp ) { /* bubble up */
HEAP_SWAP(h->p[i], h->p[temp], buf) ;
SET_OFFSET(h, i);
}
} else { /* must move down */
h->p[i].key = new_key ;
while ( (temp = HEAP_LEFT(i)) <= max ) { /* found left child */
if ((temp != max) && DN_KEY_GT(h->p[temp].key, h->p[temp+1].key))
temp++ ; /* select child with min key */
if (DN_KEY_GT(new_key, h->p[temp].key)) { /* go down */
HEAP_SWAP(h->p[i], h->p[temp], buf) ;
SET_OFFSET(h, i);
} else
break ;
i = temp ;
}
}
SET_OFFSET(h, i);
}
#endif /* heap_move, unused */
/*
* heapify() will reorganize data inside an array to maintain the
* heap property. It is needed when we delete a bunch of entries.
*/
static void
heapify(struct dn_heap *h)
{
int i ;
for (i = 0 ; i < h->elements ; i++ )
heap_insert(h, i , NULL) ;
}
/*
* cleanup the heap and free data structure
*/
static void
heap_free(struct dn_heap *h)
{
if (h->size >0 )
free(h->p, M_DUMMYNET);
bzero(h, sizeof(*h) );
}
/*
* --- end of heap management functions ---
*/
/*
* Scheduler functions:
*
* transmit_event() is called when the delay-line needs to enter
* the scheduler, either because of existing pkts getting ready,
* or new packets entering the queue. The event handled is the delivery
* time of the packet.
*
* ready_event() does something similar with fixed-rate queues, and the
* event handled is the finish time of the head pkt.
*
* wfq_ready_event() does something similar with WF2Q queues, and the
* event handled is the start time of the head pkt.
*
* In all cases, we make sure that the data structures are consistent
* before passing pkts out, because this might trigger recursive
* invocations of the procedures.
*/
static void
transmit_event(struct dn_pipe *pipe)
{
struct dn_pkt *pkt ;
while ( (pkt = pipe->head) && DN_KEY_LEQ(pkt->output_time, curr_time) ) {
/*
* first unlink, then call procedures, since ip_input() can invoke
* ip_output() and viceversa, thus causing nested calls
*/
pipe->head = DN_NEXT(pkt) ;
/*
* The actual mbuf is preceded by a struct dn_pkt, resembling an mbuf
* (NOT A REAL one, just a small block of malloc'ed memory) with
* m_type = MT_TAG, m_flags = PACKET_TAG_DUMMYNET
* dn_m (m_next) = actual mbuf to be processed by ip_input/output
* and some other fields.
* The block IS FREED HERE because it contains parameters passed
* to the called routine.
*/
switch (pkt->dn_dir) {
case DN_TO_IP_OUT:
(void)ip_output((struct mbuf *)pkt, NULL, NULL, 0, NULL);
rt_unref (pkt->ro.ro_rt) ;
break ;
case DN_TO_IP_IN :
ip_input((struct mbuf *)pkt) ;
break ;
case DN_TO_BDG_FWD :
if (!BDG_LOADED) {
/* somebody unloaded the bridge module. Drop pkt */
printf("-- dropping bridged packet trapped in pipe--\n");
m_freem(pkt->dn_m);
break;
} /* fallthrough */
case DN_TO_ETH_DEMUX:
{
struct mbuf *m = (struct mbuf *)pkt ;
struct ether_header *eh;
if (pkt->dn_m->m_len < ETHER_HDR_LEN &&
(pkt->dn_m = m_pullup(pkt->dn_m, ETHER_HDR_LEN)) == NULL) {
printf("dummynet/bridge: pullup fail, dropping pkt\n");
break;
}
/*
* same as ether_input, make eh be a pointer into the mbuf
*/
eh = mtod(pkt->dn_m, struct ether_header *);
m_adj(pkt->dn_m, ETHER_HDR_LEN);
/*
* bdg_forward() wants a pointer to the pseudo-mbuf-header, but
* on return it will supply the pointer to the actual packet
* (originally pkt->dn_m, but could be something else now) if
* it has not consumed it.
*/
if (pkt->dn_dir == DN_TO_BDG_FWD) {
m = bdg_forward_ptr(m, eh, pkt->ifp);
if (m)
m_freem(m);
} else
ether_demux(NULL, eh, m); /* which consumes the mbuf */
}
break ;
case DN_TO_ETH_OUT:
ether_output_frame(pkt->ifp, (struct mbuf *)pkt);
break;
default:
printf("dummynet: bad switch %d!\n", pkt->dn_dir);
m_freem(pkt->dn_m);
break ;
}
free(pkt, M_DUMMYNET);
}
/* if there are leftover packets, put into the heap for next event */
if ( (pkt = pipe->head) )
heap_insert(&extract_heap, pkt->output_time, pipe ) ;
/* XXX should check errors on heap_insert, by draining the
* whole pipe p and hoping in the future we are more successful
*/
}
/*
* the following macro computes how many ticks we have to wait
* before being able to transmit a packet. The credit is taken from
* either a pipe (WF2Q) or a flow_queue (per-flow queueing)
*/
#define SET_TICKS(pkt, q, p) \
(pkt->dn_m->m_pkthdr.len*8*hz - (q)->numbytes + p->bandwidth - 1 ) / \
p->bandwidth ;
/*
* extract pkt from queue, compute output time (could be now)
* and put into delay line (p_queue)
*/
static void
move_pkt(struct dn_pkt *pkt, struct dn_flow_queue *q,
struct dn_pipe *p, int len)
{
q->head = DN_NEXT(pkt) ;
q->len-- ;
q->len_bytes -= len ;
pkt->output_time = curr_time + p->delay ;
if (p->head == NULL)
p->head = pkt;
else
DN_NEXT(p->tail) = pkt;
p->tail = pkt;
DN_NEXT(p->tail) = NULL;
}
/*
* ready_event() is invoked every time the queue must enter the
* scheduler, either because the first packet arrives, or because
* a previously scheduled event fired.
* On invokation, drain as many pkts as possible (could be 0) and then
* if there are leftover packets reinsert the pkt in the scheduler.
*/
static void
ready_event(struct dn_flow_queue *q)
{
struct dn_pkt *pkt;
struct dn_pipe *p = q->fs->pipe ;
int p_was_empty ;
if (p == NULL) {
printf("ready_event- pipe is gone\n");
return ;
}
p_was_empty = (p->head == NULL) ;
/*
* schedule fixed-rate queues linked to this pipe:
* Account for the bw accumulated since last scheduling, then
* drain as many pkts as allowed by q->numbytes and move to
* the delay line (in p) computing output time.
* bandwidth==0 (no limit) means we can drain the whole queue,
* setting len_scaled = 0 does the job.
*/
q->numbytes += ( curr_time - q->sched_time ) * p->bandwidth;
while ( (pkt = q->head) != NULL ) {
int len = pkt->dn_m->m_pkthdr.len;
int len_scaled = p->bandwidth ? len*8*hz : 0 ;
if (len_scaled > q->numbytes )
break ;
q->numbytes -= len_scaled ;
move_pkt(pkt, q, p, len);
}
/*
* If we have more packets queued, schedule next ready event
* (can only occur when bandwidth != 0, otherwise we would have
* flushed the whole queue in the previous loop).
* To this purpose we record the current time and compute how many
* ticks to go for the finish time of the packet.
*/
if ( (pkt = q->head) != NULL ) { /* this implies bandwidth != 0 */
dn_key t = SET_TICKS(pkt, q, p); /* ticks i have to wait */
q->sched_time = curr_time ;
heap_insert(&ready_heap, curr_time + t, (void *)q );
/* XXX should check errors on heap_insert, and drain the whole
* queue on error hoping next time we are luckier.
*/
} else /* RED needs to know when the queue becomes empty */
q->q_time = curr_time;
/*
* If the delay line was empty call transmit_event(p) now.
* Otherwise, the scheduler will take care of it.
*/
if (p_was_empty)
transmit_event(p);
}
/*
* Called when we can transmit packets on WF2Q queues. Take pkts out of
* the queues at their start time, and enqueue into the delay line.
* Packets are drained until p->numbytes < 0. As long as
* len_scaled >= p->numbytes, the packet goes into the delay line
* with a deadline p->delay. For the last packet, if p->numbytes<0,
* there is an additional delay.
*/
static void
ready_event_wfq(struct dn_pipe *p)
{
int p_was_empty = (p->head == NULL) ;
struct dn_heap *sch = &(p->scheduler_heap);
struct dn_heap *neh = &(p->not_eligible_heap) ;
if (p->if_name[0] == 0) /* tx clock is simulated */
p->numbytes += ( curr_time - p->sched_time ) * p->bandwidth;
else { /* tx clock is for real, the ifq must be empty or this is a NOP */
if (p->ifp && p->ifp->if_snd.ifq_head != NULL)
return ;
else {
DEB(printf("pipe %d ready from %s --\n",
p->pipe_nr, p->if_name);)
}
}
/*
* While we have backlogged traffic AND credit, we need to do
* something on the queue.
*/
while ( p->numbytes >=0 && (sch->elements>0 || neh->elements >0) ) {
if (sch->elements > 0) { /* have some eligible pkts to send out */
struct dn_flow_queue *q = sch->p[0].object ;
struct dn_pkt *pkt = q->head;
struct dn_flow_set *fs = q->fs;
u_int64_t len = pkt->dn_m->m_pkthdr.len;
int len_scaled = p->bandwidth ? len*8*hz : 0 ;
heap_extract(sch, NULL); /* remove queue from heap */
p->numbytes -= len_scaled ;
move_pkt(pkt, q, p, len);
p->V += (len<<MY_M) / p->sum ; /* update V */
q->S = q->F ; /* update start time */
if (q->len == 0) { /* Flow not backlogged any more */
fs->backlogged-- ;
heap_insert(&(p->idle_heap), q->F, q);
} else { /* still backlogged */
/*
* update F and position in backlogged queue, then
* put flow in not_eligible_heap (we will fix this later).
*/
len = (q->head)->dn_m->m_pkthdr.len;
q->F += (len<<MY_M)/(u_int64_t) fs->weight ;
if (DN_KEY_LEQ(q->S, p->V))
heap_insert(neh, q->S, q);
else
heap_insert(sch, q->F, q);
}
}
/*
* now compute V = max(V, min(S_i)). Remember that all elements in sch
* have by definition S_i <= V so if sch is not empty, V is surely
* the max and we must not update it. Conversely, if sch is empty
* we only need to look at neh.
*/
if (sch->elements == 0 && neh->elements > 0)
p->V = MAX64 ( p->V, neh->p[0].key );
/* move from neh to sch any packets that have become eligible */
while (neh->elements > 0 && DN_KEY_LEQ(neh->p[0].key, p->V) ) {
struct dn_flow_queue *q = neh->p[0].object ;
heap_extract(neh, NULL);
heap_insert(sch, q->F, q);
}
if (p->if_name[0] != '\0') {/* tx clock is from a real thing */
p->numbytes = -1 ; /* mark not ready for I/O */
break ;
}
}
if (sch->elements == 0 && neh->elements == 0 && p->numbytes >= 0
&& p->idle_heap.elements > 0) {
/*
* no traffic and no events scheduled. We can get rid of idle-heap.
*/
int i ;
for (i = 0 ; i < p->idle_heap.elements ; i++) {
struct dn_flow_queue *q = p->idle_heap.p[i].object ;
q->F = 0 ;
q->S = q->F + 1 ;
}
p->sum = 0 ;
p->V = 0 ;
p->idle_heap.elements = 0 ;
}
/*
* If we are getting clocks from dummynet (not a real interface) and
* If we are under credit, schedule the next ready event.
* Also fix the delivery time of the last packet.
*/
if (p->if_name[0]==0 && p->numbytes < 0) { /* this implies bandwidth >0 */
dn_key t=0 ; /* number of ticks i have to wait */
if (p->bandwidth > 0)
t = ( p->bandwidth -1 - p->numbytes) / p->bandwidth ;
p->tail->output_time += t ;
p->sched_time = curr_time ;
heap_insert(&wfq_ready_heap, curr_time + t, (void *)p);
/* XXX should check errors on heap_insert, and drain the whole
* queue on error hoping next time we are luckier.
*/
}
/*
* If the delay line was empty call transmit_event(p) now.
* Otherwise, the scheduler will take care of it.
*/
if (p_was_empty)
transmit_event(p);
}
/*
* This is called once per tick, or HZ times per second. It is used to
* increment the current tick counter and schedule expired events.
*/
static void
dummynet(void * __unused unused)
{
void *p ; /* generic parameter to handler */
struct dn_heap *h ;
int s ;
struct dn_heap *heaps[3];
int i;
struct dn_pipe *pe ;
heaps[0] = &ready_heap ; /* fixed-rate queues */
heaps[1] = &wfq_ready_heap ; /* wfq queues */
heaps[2] = &extract_heap ; /* delay line */
s = splimp(); /* see note on top, splnet() is not enough */
curr_time++ ;
for (i=0; i < 3 ; i++) {
h = heaps[i];
while (h->elements > 0 && DN_KEY_LEQ(h->p[0].key, curr_time) ) {
DDB(if (h->p[0].key > curr_time)
printf("-- dummynet: warning, heap %d is %d ticks late\n",
i, (int)(curr_time - h->p[0].key));)
p = h->p[0].object ; /* store a copy before heap_extract */
heap_extract(h, NULL); /* need to extract before processing */
if (i == 0)
ready_event(p) ;
else if (i == 1) {
struct dn_pipe *pipe = p;
if (pipe->if_name[0] != '\0')
printf("*** bad ready_event_wfq for pipe %s\n",
pipe->if_name);
else
ready_event_wfq(p) ;
} else
transmit_event(p);
}
}
/* sweep pipes trying to expire idle flow_queues */
for (pe = all_pipes; pe ; pe = pe->next )
if (pe->idle_heap.elements > 0 &&
DN_KEY_LT(pe->idle_heap.p[0].key, pe->V) ) {
struct dn_flow_queue *q = pe->idle_heap.p[0].object ;
heap_extract(&(pe->idle_heap), NULL);
q->S = q->F + 1 ; /* mark timestamp as invalid */
pe->sum -= q->fs->weight ;
}
splx(s);
dn_timeout = timeout(dummynet, NULL, 1);
}
/*
* called by an interface when tx_rdy occurs.
*/
int
if_tx_rdy(struct ifnet *ifp)
{
struct dn_pipe *p;
for (p = all_pipes; p ; p = p->next )
if (p->ifp == ifp)
break ;
if (p == NULL) {
char buf[32];
sprintf(buf, "%s%d",ifp->if_name, ifp->if_unit);
for (p = all_pipes; p ; p = p->next )
if (!strcmp(p->if_name, buf) ) {
p->ifp = ifp ;
DEB(printf("++ tx rdy from %s (now found)\n", buf);)
break ;
}
}
if (p != NULL) {
DEB(printf("++ tx rdy from %s%d - qlen %d\n", ifp->if_name,
ifp->if_unit, ifp->if_snd.ifq_len);)
p->numbytes = 0 ; /* mark ready for I/O */
ready_event_wfq(p);
}
return 0;
}
/*
* Unconditionally expire empty queues in case of shortage.
* Returns the number of queues freed.
*/
static int
expire_queues(struct dn_flow_set *fs)
{
struct dn_flow_queue *q, *prev ;
int i, initial_elements = fs->rq_elements ;
if (fs->last_expired == time_second)
return 0 ;
fs->last_expired = time_second ;
for (i = 0 ; i <= fs->rq_size ; i++) /* last one is overflow */
for (prev=NULL, q = fs->rq[i] ; q != NULL ; )
if (q->head != NULL || q->S != q->F+1) {
prev = q ;
q = q->next ;
} else { /* entry is idle, expire it */
struct dn_flow_queue *old_q = q ;
if (prev != NULL)
prev->next = q = q->next ;
else
fs->rq[i] = q = q->next ;
fs->rq_elements-- ;
free(old_q, M_DUMMYNET);
}
return initial_elements - fs->rq_elements ;
}
/*
* If room, create a new queue and put at head of slot i;
* otherwise, create or use the default queue.
*/
static struct dn_flow_queue *
create_queue(struct dn_flow_set *fs, int i)
{
struct dn_flow_queue *q ;
if (fs->rq_elements > fs->rq_size * dn_max_ratio &&
expire_queues(fs) == 0) {
/*
* No way to get room, use or create overflow queue.
*/
i = fs->rq_size ;
if ( fs->rq[i] != NULL )
return fs->rq[i] ;
}
q = malloc(sizeof(*q), M_DUMMYNET, M_DONTWAIT | M_ZERO);
if (q == NULL) {
printf("sorry, cannot allocate queue for new flow\n");
return NULL ;
}
q->fs = fs ;
q->hash_slot = i ;
q->next = fs->rq[i] ;
q->S = q->F + 1; /* hack - mark timestamp as invalid */
fs->rq[i] = q ;
fs->rq_elements++ ;
return q ;
}
/*
* Given a flow_set and a pkt in last_pkt, find a matching queue
* after appropriate masking. The queue is moved to front
* so that further searches take less time.
*/
static struct dn_flow_queue *
find_queue(struct dn_flow_set *fs, struct ipfw_flow_id *id)
{
int i = 0 ; /* we need i and q for new allocations */
struct dn_flow_queue *q, *prev;
if ( !(fs->flags_fs & DN_HAVE_FLOW_MASK) )
q = fs->rq[0] ;
else {
/* first, do the masking */
id->dst_ip &= fs->flow_mask.dst_ip ;
id->src_ip &= fs->flow_mask.src_ip ;
id->dst_port &= fs->flow_mask.dst_port ;
id->src_port &= fs->flow_mask.src_port ;
id->proto &= fs->flow_mask.proto ;
id->flags = 0 ; /* we don't care about this one */
/* then, hash function */
i = ( (id->dst_ip) & 0xffff ) ^
( (id->dst_ip >> 15) & 0xffff ) ^
( (id->src_ip << 1) & 0xffff ) ^
( (id->src_ip >> 16 ) & 0xffff ) ^
(id->dst_port << 1) ^ (id->src_port) ^
(id->proto );
i = i % fs->rq_size ;
/* finally, scan the current list for a match */
searches++ ;
for (prev=NULL, q = fs->rq[i] ; q ; ) {
search_steps++;
if (bcmp(id, &(q->id), sizeof(q->id) ) == 0)
break ; /* found */
else if (pipe_expire && q->head == NULL && q->S == q->F+1 ) {
/* entry is idle and not in any heap, expire it */
struct dn_flow_queue *old_q = q ;
if (prev != NULL)
prev->next = q = q->next ;
else
fs->rq[i] = q = q->next ;
fs->rq_elements-- ;
free(old_q, M_DUMMYNET);
continue ;
}
prev = q ;
q = q->next ;
}
if (q && prev != NULL) { /* found and not in front */
prev->next = q->next ;
q->next = fs->rq[i] ;
fs->rq[i] = q ;
}
}
if (q == NULL) { /* no match, need to allocate a new entry */
q = create_queue(fs, i);
if (q != NULL)
q->id = *id ;
}
return q ;
}
static int
red_drops(struct dn_flow_set *fs, struct dn_flow_queue *q, int len)
{
/*
* RED algorithm
*
* RED calculates the average queue size (avg) using a low-pass filter
* with an exponential weighted (w_q) moving average:
* avg <- (1-w_q) * avg + w_q * q_size
* where q_size is the queue length (measured in bytes or * packets).
*
* If q_size == 0, we compute the idle time for the link, and set
* avg = (1 - w_q)^(idle/s)
* where s is the time needed for transmitting a medium-sized packet.
*
* Now, if avg < min_th the packet is enqueued.
* If avg > max_th the packet is dropped. Otherwise, the packet is
* dropped with probability P function of avg.
*
*/
int64_t p_b = 0;
/* queue in bytes or packets ? */
u_int q_size = (fs->flags_fs & DN_QSIZE_IS_BYTES) ? q->len_bytes : q->len;
DEB(printf("\n%d q: %2u ", (int) curr_time, q_size);)
/* average queue size estimation */
if (q_size != 0) {
/*
* queue is not empty, avg <- avg + (q_size - avg) * w_q
*/
int diff = SCALE(q_size) - q->avg;
int64_t v = SCALE_MUL((int64_t) diff, (int64_t) fs->w_q);
q->avg += (int) v;
} else {
/*
* queue is empty, find for how long the queue has been
* empty and use a lookup table for computing
* (1 - * w_q)^(idle_time/s) where s is the time to send a
* (small) packet.
* XXX check wraps...
*/
if (q->avg) {
u_int t = (curr_time - q->q_time) / fs->lookup_step;
q->avg = (t < fs->lookup_depth) ?
SCALE_MUL(q->avg, fs->w_q_lookup[t]) : 0;
}
}
DEB(printf("avg: %u ", SCALE_VAL(q->avg));)
/* should i drop ? */
if (q->avg < fs->min_th) {
q->count = -1;
return 0; /* accept packet ; */
}
if (q->avg >= fs->max_th) { /* average queue >= max threshold */
if (fs->flags_fs & DN_IS_GENTLE_RED) {
/*
* According to Gentle-RED, if avg is greater than max_th the
* packet is dropped with a probability
* p_b = c_3 * avg - c_4
* where c_3 = (1 - max_p) / max_th, and c_4 = 1 - 2 * max_p
*/
p_b = SCALE_MUL((int64_t) fs->c_3, (int64_t) q->avg) - fs->c_4;
} else {
q->count = -1;
printf("- drop");
return 1 ;
}
} else if (q->avg > fs->min_th) {
/*
* we compute p_b using the linear dropping function p_b = c_1 *
* avg - c_2, where c_1 = max_p / (max_th - min_th), and c_2 =
* max_p * min_th / (max_th - min_th)
*/
p_b = SCALE_MUL((int64_t) fs->c_1, (int64_t) q->avg) - fs->c_2;
}
if (fs->flags_fs & DN_QSIZE_IS_BYTES)
p_b = (p_b * len) / fs->max_pkt_size;
if (++q->count == 0)
q->random = random() & 0xffff;
else {
/*
* q->count counts packets arrived since last drop, so a greater
* value of q->count means a greater packet drop probability.
*/
if (SCALE_MUL(p_b, SCALE((int64_t) q->count)) > q->random) {
q->count = 0;
DEB(printf("- red drop");)
/* after a drop we calculate a new random value */
q->random = random() & 0xffff;
return 1; /* drop */
}
}
/* end of RED algorithm */
return 0 ; /* accept */
}
static __inline
struct dn_flow_set *
locate_flowset(int pipe_nr, struct ip_fw *rule)
{
#if IPFW2
struct dn_flow_set *fs;
ipfw_insn *cmd = rule->cmd + rule->act_ofs;
if (cmd->opcode == O_LOG)
cmd += F_LEN(cmd);
fs = ((ipfw_insn_pipe *)cmd)->pipe_ptr;
if (fs != NULL)
return fs;
if (cmd->opcode == O_QUEUE)
#else /* !IPFW2 */
struct dn_flow_set *fs = NULL ;
if ( (rule->fw_flg & IP_FW_F_COMMAND) == IP_FW_F_QUEUE )
#endif /* !IPFW2 */
for (fs=all_flow_sets; fs && fs->fs_nr != pipe_nr; fs=fs->next)
;
else {
struct dn_pipe *p1;
for (p1 = all_pipes; p1 && p1->pipe_nr != pipe_nr; p1 = p1->next)
;
if (p1 != NULL)
fs = &(p1->fs) ;
}
/* record for the future */
#if IPFW2
((ipfw_insn_pipe *)cmd)->pipe_ptr = fs;
#else
if (fs != NULL)
rule->pipe_ptr = fs;
#endif
return fs ;
}
/*
* dummynet hook for packets. Below 'pipe' is a pipe or a queue
* depending on whether WF2Q or fixed bw is used.
*
* pipe_nr pipe or queue the packet is destined for.
* dir where shall we send the packet after dummynet.
* m the mbuf with the packet
* ifp the 'ifp' parameter from the caller.
* NULL in ip_input, destination interface in ip_output,
* real_dst in bdg_forward
* ro route parameter (only used in ip_output, NULL otherwise)
* dst destination address, only used by ip_output
* rule matching rule, in case of multiple passes
* flags flags from the caller, only used in ip_output
*
*/
static int
dummynet_io(struct mbuf *m, int pipe_nr, int dir, struct ip_fw_args *fwa)
{
struct dn_pkt *pkt;
struct dn_flow_set *fs;
struct dn_pipe *pipe ;
u_int64_t len = m->m_pkthdr.len ;
struct dn_flow_queue *q = NULL ;
int s = splimp();
int is_pipe;
#if IPFW2
ipfw_insn *cmd = fwa->rule->cmd + fwa->rule->act_ofs;
if (cmd->opcode == O_LOG)
cmd += F_LEN(cmd);
is_pipe = (cmd->opcode == O_PIPE);
#else
is_pipe = (fwa->rule->fw_flg & IP_FW_F_COMMAND) == IP_FW_F_PIPE;
#endif
pipe_nr &= 0xffff ;
/*
* this is a dummynet rule, so we expect a O_PIPE or O_QUEUE rule
*/
fs = locate_flowset(pipe_nr, fwa->rule);
if (fs == NULL)
goto dropit ; /* this queue/pipe does not exist! */
pipe = fs->pipe ;
if (pipe == NULL) { /* must be a queue, try find a matching pipe */
for (pipe = all_pipes; pipe && pipe->pipe_nr != fs->parent_nr;
pipe = pipe->next)
;
if (pipe != NULL)
fs->pipe = pipe ;
else {
printf("No pipe %d for queue %d, drop pkt\n",
fs->parent_nr, fs->fs_nr);
goto dropit ;
}
}
q = find_queue(fs, &(fwa->f_id));
if ( q == NULL )
goto dropit ; /* cannot allocate queue */
/*
* update statistics, then check reasons to drop pkt
*/
q->tot_bytes += len ;
q->tot_pkts++ ;
if ( fs->plr && random() < fs->plr )
goto dropit ; /* random pkt drop */
if ( fs->flags_fs & DN_QSIZE_IS_BYTES) {
if (q->len_bytes > fs->qsize)
goto dropit ; /* queue size overflow */
} else {
if (q->len >= fs->qsize)
goto dropit ; /* queue count overflow */
}
if ( fs->flags_fs & DN_IS_RED && red_drops(fs, q, len) )
goto dropit ;
/* XXX expensive to zero, see if we can remove it*/
pkt = (struct dn_pkt *)malloc(sizeof (*pkt), M_DUMMYNET, M_NOWAIT|M_ZERO);
if ( pkt == NULL )
goto dropit ; /* cannot allocate packet header */
/* ok, i can handle the pkt now... */
/* build and enqueue packet + parameters */
pkt->hdr.mh_type = MT_TAG;
pkt->hdr.mh_flags = PACKET_TAG_DUMMYNET;
pkt->rule = fwa->rule ;
DN_NEXT(pkt) = NULL;
pkt->dn_m = m;
pkt->dn_dir = dir ;
pkt->ifp = fwa->oif;
if (dir == DN_TO_IP_OUT) {
/*
* We need to copy *ro because for ICMP pkts (and maybe others)
* the caller passed a pointer into the stack; dst might also be
* a pointer into *ro so it needs to be updated.
*/
pkt->ro = *(fwa->ro);
if (fwa->ro->ro_rt)
fwa->ro->ro_rt->rt_refcnt++ ;
if (fwa->dst == (struct sockaddr_in *)&fwa->ro->ro_dst) /* dst points into ro */
fwa->dst = (struct sockaddr_in *)&(pkt->ro.ro_dst) ;
pkt->dn_dst = fwa->dst;
pkt->flags = fwa->flags;
}
if (q->head == NULL)
q->head = pkt;
else
DN_NEXT(q->tail) = pkt;
q->tail = pkt;
q->len++;
q->len_bytes += len ;
if ( q->head != pkt ) /* flow was not idle, we are done */
goto done;
/*
* If we reach this point the flow was previously idle, so we need
* to schedule it. This involves different actions for fixed-rate or
* WF2Q queues.
*/
if (is_pipe) {
/*
* Fixed-rate queue: just insert into the ready_heap.
*/
dn_key t = 0 ;
if (pipe->bandwidth)
t = SET_TICKS(pkt, q, pipe);
q->sched_time = curr_time ;
if (t == 0) /* must process it now */
ready_event( q );
else
heap_insert(&ready_heap, curr_time + t , q );
} else {
/*
* WF2Q. First, compute start time S: if the flow was idle (S=F+1)
* set S to the virtual time V for the controlling pipe, and update
* the sum of weights for the pipe; otherwise, remove flow from
* idle_heap and set S to max(F,V).
* Second, compute finish time F = S + len/weight.
* Third, if pipe was idle, update V=max(S, V).
* Fourth, count one more backlogged flow.
*/
if (DN_KEY_GT(q->S, q->F)) { /* means timestamps are invalid */
q->S = pipe->V ;
pipe->sum += fs->weight ; /* add weight of new queue */
} else {
heap_extract(&(pipe->idle_heap), q);
q->S = MAX64(q->F, pipe->V ) ;
}
q->F = q->S + ( len<<MY_M )/(u_int64_t) fs->weight;
if (pipe->not_eligible_heap.elements == 0 &&
pipe->scheduler_heap.elements == 0)
pipe->V = MAX64 ( q->S, pipe->V );
fs->backlogged++ ;
/*
* Look at eligibility. A flow is not eligibile if S>V (when
* this happens, it means that there is some other flow already
* scheduled for the same pipe, so the scheduler_heap cannot be
* empty). If the flow is not eligible we just store it in the
* not_eligible_heap. Otherwise, we store in the scheduler_heap
* and possibly invoke ready_event_wfq() right now if there is
* leftover credit.
* Note that for all flows in scheduler_heap (SCH), S_i <= V,
* and for all flows in not_eligible_heap (NEH), S_i > V .
* So when we need to compute max( V, min(S_i) ) forall i in SCH+NEH,
* we only need to look into NEH.
*/
if (DN_KEY_GT(q->S, pipe->V) ) { /* not eligible */
if (pipe->scheduler_heap.elements == 0)
printf("++ ouch! not eligible but empty scheduler!\n");
heap_insert(&(pipe->not_eligible_heap), q->S, q);
} else {
heap_insert(&(pipe->scheduler_heap), q->F, q);
if (pipe->numbytes >= 0) { /* pipe is idle */
if (pipe->scheduler_heap.elements != 1)
printf("*** OUCH! pipe should have been idle!\n");
DEB(printf("Waking up pipe %d at %d\n",
pipe->pipe_nr, (int)(q->F >> MY_M)); )
pipe->sched_time = curr_time ;
ready_event_wfq(pipe);
}
}
}
done:
splx(s);
return 0;
dropit:
splx(s);
if (q)
q->drops++ ;
m_freem(m);
return ( (fs && (fs->flags_fs & DN_NOERROR)) ? 0 : ENOBUFS);
}
/*
* Below, the rt_unref is only needed when (pkt->dn_dir == DN_TO_IP_OUT)
* Doing this would probably save us the initial bzero of dn_pkt
*/
#define DN_FREE_PKT(pkt) { \
struct dn_pkt *n = pkt ; \
rt_unref ( n->ro.ro_rt ) ; \
m_freem(n->dn_m); \
pkt = DN_NEXT(n) ; \
free(n, M_DUMMYNET) ; }
/*
* Dispose all packets and flow_queues on a flow_set.
* If all=1, also remove red lookup table and other storage,
* including the descriptor itself.
* For the one in dn_pipe MUST also cleanup ready_heap...
*/
static void
purge_flow_set(struct dn_flow_set *fs, int all)
{
struct dn_pkt *pkt ;
struct dn_flow_queue *q, *qn ;
int i ;
for (i = 0 ; i <= fs->rq_size ; i++ ) {
for (q = fs->rq[i] ; q ; q = qn ) {
for (pkt = q->head ; pkt ; )
DN_FREE_PKT(pkt) ;
qn = q->next ;
free(q, M_DUMMYNET);
}
fs->rq[i] = NULL ;
}
fs->rq_elements = 0 ;
if (all) {
/* RED - free lookup table */
if (fs->w_q_lookup)
free(fs->w_q_lookup, M_DUMMYNET);
if (fs->rq)
free(fs->rq, M_DUMMYNET);
/* if this fs is not part of a pipe, free it */
if (fs->pipe && fs != &(fs->pipe->fs) )
free(fs, M_DUMMYNET);
}
}
/*
* Dispose all packets queued on a pipe (not a flow_set).
* Also free all resources associated to a pipe, which is about
* to be deleted.
*/
static void
purge_pipe(struct dn_pipe *pipe)
{
struct dn_pkt *pkt ;
purge_flow_set( &(pipe->fs), 1 );
for (pkt = pipe->head ; pkt ; )
DN_FREE_PKT(pkt) ;
heap_free( &(pipe->scheduler_heap) );
heap_free( &(pipe->not_eligible_heap) );
heap_free( &(pipe->idle_heap) );
}
/*
* Delete all pipes and heaps returning memory. Must also
* remove references from all ipfw rules to all pipes.
*/
static void
dummynet_flush()
{
struct dn_pipe *curr_p, *p ;
struct dn_flow_set *fs, *curr_fs;
int s ;
s = splimp() ;
/* remove all references to pipes ...*/
flush_pipe_ptrs(NULL);
/* prevent future matches... */
p = all_pipes ;
all_pipes = NULL ;
fs = all_flow_sets ;
all_flow_sets = NULL ;
/* and free heaps so we don't have unwanted events */
heap_free(&ready_heap);
heap_free(&wfq_ready_heap);
heap_free(&extract_heap);
splx(s) ;
/*
* Now purge all queued pkts and delete all pipes
*/
/* scan and purge all flow_sets. */
for ( ; fs ; ) {
curr_fs = fs ;
fs = fs->next ;
purge_flow_set(curr_fs, 1);
}
for ( ; p ; ) {
purge_pipe(p);
curr_p = p ;
p = p->next ;
free(curr_p, M_DUMMYNET);
}
}
extern struct ip_fw *ip_fw_default_rule ;
static void
dn_rule_delete_fs(struct dn_flow_set *fs, void *r)
{
int i ;
struct dn_flow_queue *q ;
struct dn_pkt *pkt ;
for (i = 0 ; i <= fs->rq_size ; i++) /* last one is ovflow */
for (q = fs->rq[i] ; q ; q = q->next )
for (pkt = q->head ; pkt ; pkt = DN_NEXT(pkt) )
if (pkt->rule == r)
pkt->rule = ip_fw_default_rule ;
}
/*
* when a firewall rule is deleted, scan all queues and remove the flow-id
* from packets matching this rule.
*/
void
dn_rule_delete(void *r)
{
struct dn_pipe *p ;
struct dn_pkt *pkt ;
struct dn_flow_set *fs ;
/*
* If the rule references a queue (dn_flow_set), then scan
* the flow set, otherwise scan pipes. Should do either, but doing
* both does not harm.
*/
for ( fs = all_flow_sets ; fs ; fs = fs->next )
dn_rule_delete_fs(fs, r);
for ( p = all_pipes ; p ; p = p->next ) {
fs = &(p->fs) ;
dn_rule_delete_fs(fs, r);
for (pkt = p->head ; pkt ; pkt = DN_NEXT(pkt) )
if (pkt->rule == r)
pkt->rule = ip_fw_default_rule ;
}
}
/*
* setup RED parameters
*/
static int
config_red(struct dn_flow_set *p, struct dn_flow_set * x)
{
int i;
x->w_q = p->w_q;
x->min_th = SCALE(p->min_th);
x->max_th = SCALE(p->max_th);
x->max_p = p->max_p;
x->c_1 = p->max_p / (p->max_th - p->min_th);
x->c_2 = SCALE_MUL(x->c_1, SCALE(p->min_th));
if (x->flags_fs & DN_IS_GENTLE_RED) {
x->c_3 = (SCALE(1) - p->max_p) / p->max_th;
x->c_4 = (SCALE(1) - 2 * p->max_p);
}
/* if the lookup table already exist, free and create it again */
if (x->w_q_lookup) {
free(x->w_q_lookup, M_DUMMYNET);
x->w_q_lookup = NULL ;
}
if (red_lookup_depth == 0) {
printf("\nnet.inet.ip.dummynet.red_lookup_depth must be > 0");
free(x, M_DUMMYNET);
return EINVAL;
}
x->lookup_depth = red_lookup_depth;
x->w_q_lookup = (u_int *) malloc(x->lookup_depth * sizeof(int),
M_DUMMYNET, M_DONTWAIT);
if (x->w_q_lookup == NULL) {
printf("sorry, cannot allocate red lookup table\n");
free(x, M_DUMMYNET);
return ENOSPC;
}
/* fill the lookup table with (1 - w_q)^x */
x->lookup_step = p->lookup_step ;
x->lookup_weight = p->lookup_weight ;
x->w_q_lookup[0] = SCALE(1) - x->w_q;
for (i = 1; i < x->lookup_depth; i++)
x->w_q_lookup[i] = SCALE_MUL(x->w_q_lookup[i - 1], x->lookup_weight);
if (red_avg_pkt_size < 1)
red_avg_pkt_size = 512 ;
x->avg_pkt_size = red_avg_pkt_size ;
if (red_max_pkt_size < 1)
red_max_pkt_size = 1500 ;
x->max_pkt_size = red_max_pkt_size ;
return 0 ;
}
static int
alloc_hash(struct dn_flow_set *x, struct dn_flow_set *pfs)
{
if (x->flags_fs & DN_HAVE_FLOW_MASK) { /* allocate some slots */
int l = pfs->rq_size;
if (l == 0)
l = dn_hash_size;
if (l < 4)
l = 4;
else if (l > 1024)
l = 1024;
x->rq_size = l;
} else /* one is enough for null mask */
x->rq_size = 1;
x->rq = malloc((1 + x->rq_size) * sizeof(struct dn_flow_queue *),
M_DUMMYNET, M_DONTWAIT | M_ZERO);
if (x->rq == NULL) {
printf("sorry, cannot allocate queue\n");
return ENOSPC;
}
x->rq_elements = 0;
return 0 ;
}
static void
set_fs_parms(struct dn_flow_set *x, struct dn_flow_set *src)
{
x->flags_fs = src->flags_fs;
x->qsize = src->qsize;
x->plr = src->plr;
x->flow_mask = src->flow_mask;
if (x->flags_fs & DN_QSIZE_IS_BYTES) {
if (x->qsize > 1024*1024)
x->qsize = 1024*1024 ;
} else {
if (x->qsize == 0)
x->qsize = 50 ;
if (x->qsize > 100)
x->qsize = 50 ;
}
/* configuring RED */
if ( x->flags_fs & DN_IS_RED )
config_red(src, x) ; /* XXX should check errors */
}
/*
* setup pipe or queue parameters.
*/
static int
config_pipe(struct dn_pipe *p)
{
int s ;
struct dn_flow_set *pfs = &(p->fs);
/*
* The config program passes parameters as follows:
* bw = bits/second (0 means no limits),
* delay = ms, must be translated into ticks.
* qsize = slots/bytes
*/
p->delay = ( p->delay * hz ) / 1000 ;
/* We need either a pipe number or a flow_set number */
if (p->pipe_nr == 0 && pfs->fs_nr == 0)
return EINVAL ;
if (p->pipe_nr != 0 && pfs->fs_nr != 0)
return EINVAL ;
if (p->pipe_nr != 0) { /* this is a pipe */
struct dn_pipe *x, *a, *b;
/* locate pipe */
for (a = NULL , b = all_pipes ; b && b->pipe_nr < p->pipe_nr ;
a = b , b = b->next) ;
if (b == NULL || b->pipe_nr != p->pipe_nr) { /* new pipe */
x = malloc(sizeof(struct dn_pipe), M_DUMMYNET, M_DONTWAIT | M_ZERO);
if (x == NULL) {
printf("ip_dummynet.c: no memory for new pipe\n");
return ENOSPC;
}
x->pipe_nr = p->pipe_nr;
x->fs.pipe = x ;
/* idle_heap is the only one from which we extract from the middle.
*/
x->idle_heap.size = x->idle_heap.elements = 0 ;
x->idle_heap.offset=OFFSET_OF(struct dn_flow_queue, heap_pos);
} else
x = b;
x->bandwidth = p->bandwidth ;
x->numbytes = 0; /* just in case... */
bcopy(p->if_name, x->if_name, sizeof(p->if_name) );
x->ifp = NULL ; /* reset interface ptr */
x->delay = p->delay ;
set_fs_parms(&(x->fs), pfs);
if ( x->fs.rq == NULL ) { /* a new pipe */
s = alloc_hash(&(x->fs), pfs) ;
if (s) {
free(x, M_DUMMYNET);
return s ;
}
s = splimp() ;
x->next = b ;
if (a == NULL)
all_pipes = x ;
else
a->next = x ;
splx(s);
}
} else { /* config queue */
struct dn_flow_set *x, *a, *b ;
/* locate flow_set */
for (a=NULL, b=all_flow_sets ; b && b->fs_nr < pfs->fs_nr ;
a = b , b = b->next) ;
if (b == NULL || b->fs_nr != pfs->fs_nr) { /* new */
if (pfs->parent_nr == 0) /* need link to a pipe */
return EINVAL ;
x = malloc(sizeof(struct dn_flow_set),M_DUMMYNET,M_DONTWAIT|M_ZERO);
if (x == NULL) {
printf("ip_dummynet.c: no memory for new flow_set\n");
return ENOSPC;
}
x->fs_nr = pfs->fs_nr;
x->parent_nr = pfs->parent_nr;
x->weight = pfs->weight ;
if (x->weight == 0)
x->weight = 1 ;
else if (x->weight > 100)
x->weight = 100 ;
} else {
/* Change parent pipe not allowed; must delete and recreate */
if (pfs->parent_nr != 0 && b->parent_nr != pfs->parent_nr)
return EINVAL ;
x = b;
}
set_fs_parms(x, pfs);
if ( x->rq == NULL ) { /* a new flow_set */
s = alloc_hash(x, pfs) ;
if (s) {
free(x, M_DUMMYNET);
return s ;
}
s = splimp() ;
x->next = b;
if (a == NULL)
all_flow_sets = x;
else
a->next = x;
splx(s);
}
}
return 0 ;
}
/*
* Helper function to remove from a heap queues which are linked to
* a flow_set about to be deleted.
*/
static void
fs_remove_from_heap(struct dn_heap *h, struct dn_flow_set *fs)
{
int i = 0, found = 0 ;
for (; i < h->elements ;)
if ( ((struct dn_flow_queue *)h->p[i].object)->fs == fs) {
h->elements-- ;
h->p[i] = h->p[h->elements] ;
found++ ;
} else
i++ ;
if (found)
heapify(h);
}
/*
* helper function to remove a pipe from a heap (can be there at most once)
*/
static void
pipe_remove_from_heap(struct dn_heap *h, struct dn_pipe *p)
{
if (h->elements > 0) {
int i = 0 ;
for (i=0; i < h->elements ; i++ ) {
if (h->p[i].object == p) { /* found it */
h->elements-- ;
h->p[i] = h->p[h->elements] ;
heapify(h);
break ;
}
}
}
}
/*
* drain all queues. Called in case of severe mbuf shortage.
*/
void
dummynet_drain()
{
struct dn_flow_set *fs;
struct dn_pipe *p;
struct dn_pkt *pkt;
heap_free(&ready_heap);
heap_free(&wfq_ready_heap);
heap_free(&extract_heap);
/* remove all references to this pipe from flow_sets */
for (fs = all_flow_sets; fs; fs= fs->next )
purge_flow_set(fs, 0);
for (p = all_pipes; p; p= p->next ) {
purge_flow_set(&(p->fs), 0);
for (pkt = p->head ; pkt ; )
DN_FREE_PKT(pkt) ;
p->head = p->tail = NULL ;
}
}
/*
* Fully delete a pipe or a queue, cleaning up associated info.
*/
static int
delete_pipe(struct dn_pipe *p)
{
int s ;
if (p->pipe_nr == 0 && p->fs.fs_nr == 0)
return EINVAL ;
if (p->pipe_nr != 0 && p->fs.fs_nr != 0)
return EINVAL ;
if (p->pipe_nr != 0) { /* this is an old-style pipe */
struct dn_pipe *a, *b;
struct dn_flow_set *fs;
/* locate pipe */
for (a = NULL , b = all_pipes ; b && b->pipe_nr < p->pipe_nr ;
a = b , b = b->next) ;
if (b == NULL || (b->pipe_nr != p->pipe_nr) )
return EINVAL ; /* not found */
s = splimp() ;
/* unlink from list of pipes */
if (a == NULL)
all_pipes = b->next ;
else
a->next = b->next ;
/* remove references to this pipe from the ip_fw rules. */
flush_pipe_ptrs(&(b->fs));
/* remove all references to this pipe from flow_sets */
for (fs = all_flow_sets; fs; fs= fs->next )
if (fs->pipe == b) {
printf("++ ref to pipe %d from fs %d\n",
p->pipe_nr, fs->fs_nr);
fs->pipe = NULL ;
purge_flow_set(fs, 0);
}
fs_remove_from_heap(&ready_heap, &(b->fs));
purge_pipe(b); /* remove all data associated to this pipe */
/* remove reference to here from extract_heap and wfq_ready_heap */
pipe_remove_from_heap(&extract_heap, b);
pipe_remove_from_heap(&wfq_ready_heap, b);
splx(s);
free(b, M_DUMMYNET);
} else { /* this is a WF2Q queue (dn_flow_set) */
struct dn_flow_set *a, *b;
/* locate set */
for (a = NULL, b = all_flow_sets ; b && b->fs_nr < p->fs.fs_nr ;
a = b , b = b->next) ;
if (b == NULL || (b->fs_nr != p->fs.fs_nr) )
return EINVAL ; /* not found */
s = splimp() ;
if (a == NULL)
all_flow_sets = b->next ;
else
a->next = b->next ;
/* remove references to this flow_set from the ip_fw rules. */
flush_pipe_ptrs(b);
if (b->pipe != NULL) {
/* Update total weight on parent pipe and cleanup parent heaps */
b->pipe->sum -= b->weight * b->backlogged ;
fs_remove_from_heap(&(b->pipe->not_eligible_heap), b);
fs_remove_from_heap(&(b->pipe->scheduler_heap), b);
#if 1 /* XXX should i remove from idle_heap as well ? */
fs_remove_from_heap(&(b->pipe->idle_heap), b);
#endif
}
purge_flow_set(b, 1);
splx(s);
}
return 0 ;
}
/*
* helper function used to copy data from kernel in DUMMYNET_GET
*/
static char *
dn_copy_set(struct dn_flow_set *set, char *bp)
{
int i, copied = 0 ;
struct dn_flow_queue *q, *qp = (struct dn_flow_queue *)bp;
for (i = 0 ; i <= set->rq_size ; i++)
for (q = set->rq[i] ; q ; q = q->next, qp++ ) {
if (q->hash_slot != i)
printf("++ at %d: wrong slot (have %d, "
"should be %d)\n", copied, q->hash_slot, i);
if (q->fs != set)
printf("++ at %d: wrong fs ptr (have %p, should be %p)\n",
i, q->fs, set);
copied++ ;
bcopy(q, qp, sizeof( *q ) );
/* cleanup pointers */
qp->next = NULL ;
qp->head = qp->tail = NULL ;
qp->fs = NULL ;
}
if (copied != set->rq_elements)
printf("++ wrong count, have %d should be %d\n",
copied, set->rq_elements);
return (char *)qp ;
}
static int
dummynet_get(struct sockopt *sopt)
{
char *buf, *bp ; /* bp is the "copy-pointer" */
size_t size ;
struct dn_flow_set *set ;
struct dn_pipe *p ;
int s, error=0 ;
s = splimp();
/*
* compute size of data structures: list of pipes and flow_sets.
*/
for (p = all_pipes, size = 0 ; p ; p = p->next )
size += sizeof( *p ) +
p->fs.rq_elements * sizeof(struct dn_flow_queue);
for (set = all_flow_sets ; set ; set = set->next )
size += sizeof ( *set ) +
set->rq_elements * sizeof(struct dn_flow_queue);
buf = malloc(size, M_TEMP, M_DONTWAIT);
if (buf == 0) {
splx(s);
return ENOBUFS ;
}
for (p = all_pipes, bp = buf ; p ; p = p->next ) {
struct dn_pipe *pipe_bp = (struct dn_pipe *)bp ;
/*
* copy pipe descriptor into *bp, convert delay back to ms,
* then copy the flow_set descriptor(s) one at a time.
* After each flow_set, copy the queue descriptor it owns.
*/
bcopy(p, bp, sizeof( *p ) );
pipe_bp->delay = (pipe_bp->delay * 1000) / hz ;
/*
* XXX the following is a hack based on ->next being the
* first field in dn_pipe and dn_flow_set. The correct
* solution would be to move the dn_flow_set to the beginning
* of struct dn_pipe.
*/
pipe_bp->next = (struct dn_pipe *)DN_IS_PIPE ;
/* clean pointers */
pipe_bp->head = pipe_bp->tail = NULL ;
pipe_bp->fs.next = NULL ;
pipe_bp->fs.pipe = NULL ;
pipe_bp->fs.rq = NULL ;
bp += sizeof( *p ) ;
bp = dn_copy_set( &(p->fs), bp );
}
for (set = all_flow_sets ; set ; set = set->next ) {
struct dn_flow_set *fs_bp = (struct dn_flow_set *)bp ;
bcopy(set, bp, sizeof( *set ) );
/* XXX same hack as above */
fs_bp->next = (struct dn_flow_set *)DN_IS_QUEUE ;
fs_bp->pipe = NULL ;
fs_bp->rq = NULL ;
bp += sizeof( *set ) ;
bp = dn_copy_set( set, bp );
}
splx(s);
error = sooptcopyout(sopt, buf, size);
free(buf, M_TEMP);
return error ;
}
/*
* Handler for the various dummynet socket options (get, flush, config, del)
*/
static int
ip_dn_ctl(struct sockopt *sopt)
{
int error = 0 ;
struct dn_pipe *p, tmp_pipe;
/* Disallow sets in really-really secure mode. */
if (sopt->sopt_dir == SOPT_SET) {
#if __FreeBSD_version >= 500034
error = securelevel_ge(sopt->sopt_td->td_ucred, 3);
if (error)
return (error);
#else
if (securelevel >= 3)
return (EPERM);
#endif
}
switch (sopt->sopt_name) {
default :
printf("ip_dn_ctl -- unknown option %d", sopt->sopt_name);
return EINVAL ;
case IP_DUMMYNET_GET :
error = dummynet_get(sopt);
break ;
case IP_DUMMYNET_FLUSH :
dummynet_flush() ;
break ;
case IP_DUMMYNET_CONFIGURE :
p = &tmp_pipe ;
error = sooptcopyin(sopt, p, sizeof *p, sizeof *p);
if (error)
break ;
error = config_pipe(p);
break ;
case IP_DUMMYNET_DEL : /* remove a pipe or queue */
p = &tmp_pipe ;
error = sooptcopyin(sopt, p, sizeof *p, sizeof *p);
if (error)
break ;
error = delete_pipe(p);
break ;
}
return error ;
}
static void
ip_dn_init(void)
{
printf("DUMMYNET initialized (011031)\n");
all_pipes = NULL ;
all_flow_sets = NULL ;
ready_heap.size = ready_heap.elements = 0 ;
ready_heap.offset = 0 ;
wfq_ready_heap.size = wfq_ready_heap.elements = 0 ;
wfq_ready_heap.offset = 0 ;
extract_heap.size = extract_heap.elements = 0 ;
extract_heap.offset = 0 ;
ip_dn_ctl_ptr = ip_dn_ctl;
ip_dn_io_ptr = dummynet_io;
ip_dn_ruledel_ptr = dn_rule_delete;
bzero(&dn_timeout, sizeof(struct callout_handle));
dn_timeout = timeout(dummynet, NULL, 1);
}
static int
dummynet_modevent(module_t mod, int type, void *data)
{
int s;
switch (type) {
case MOD_LOAD:
s = splimp();
if (DUMMYNET_LOADED) {
splx(s);
printf("DUMMYNET already loaded\n");
return EEXIST ;
}
ip_dn_init();
splx(s);
break;
case MOD_UNLOAD:
#if !defined(KLD_MODULE)
printf("dummynet statically compiled, cannot unload\n");
return EINVAL ;
#else
s = splimp();
untimeout(dummynet, NULL, dn_timeout);
dummynet_flush();
ip_dn_ctl_ptr = NULL;
ip_dn_io_ptr = NULL;
ip_dn_ruledel_ptr = NULL;
splx(s);
#endif
break ;
default:
break ;
}
return 0 ;
}
static moduledata_t dummynet_mod = {
"dummynet",
dummynet_modevent,
NULL
};
DECLARE_MODULE(dummynet, dummynet_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_DEPEND(dummynet, ipfw, 1, 1, 1);
MODULE_VERSION(dummynet, 1);