minix/servers/inet/generic/arp.c
2012-03-25 21:58:14 +02:00

1361 lines
29 KiB
C

/*
arp.c
Copyright 1995 Philip Homburg
*/
#include "inet.h"
#include "type.h"
#include "arp.h"
#include "assert.h"
#include "buf.h"
#include "clock.h"
#include "event.h"
#include "eth.h"
#include "io.h"
THIS_FILE
#define ARP_CACHE_NR 256
#define AP_REQ_NR 32
#define ARP_HASH_NR 256
#define ARP_HASH_MASK 0xff
#define ARP_HASH_WIDTH 4
#define MAX_ARP_RETRIES 5
#define ARP_TIMEOUT (HZ/2+1) /* .5 seconds */
#ifndef ARP_EXP_TIME
#define ARP_EXP_TIME (20L*60L*HZ) /* 20 minutes */
#endif
#define ARP_NOTRCH_EXP_TIME (30*HZ) /* 30 seconds */
#define ARP_INUSE_OFFSET (60*HZ) /* an entry in the cache can be deleted
if its not used for 1 minute */
typedef struct arp46
{
ether_addr_t a46_dstaddr;
ether_addr_t a46_srcaddr;
ether_type_t a46_ethtype;
union
{
struct
{
u16_t a_hdr, a_pro;
u8_t a_hln, a_pln;
u16_t a_op;
ether_addr_t a_sha;
u8_t a_spa[4];
ether_addr_t a_tha;
u8_t a_tpa[4];
} a46_data;
char a46_dummy[ETH_MIN_PACK_SIZE-ETH_HDR_SIZE];
} a46_data;
} arp46_t;
#define a46_hdr a46_data.a46_data.a_hdr
#define a46_pro a46_data.a46_data.a_pro
#define a46_hln a46_data.a46_data.a_hln
#define a46_pln a46_data.a46_data.a_pln
#define a46_op a46_data.a46_data.a_op
#define a46_sha a46_data.a46_data.a_sha
#define a46_spa a46_data.a46_data.a_spa
#define a46_tha a46_data.a46_data.a_tha
#define a46_tpa a46_data.a46_data.a_tpa
typedef struct arp_port
{
int ap_flags;
int ap_state;
int ap_eth_port;
int ap_ip_port;
int ap_eth_fd;
ether_addr_t ap_ethaddr; /* Ethernet address of this port */
ipaddr_t ap_ipaddr; /* IP address of this port */
struct arp_req
{
timer_t ar_timer;
int ar_entry;
int ar_req_count;
} ap_req[AP_REQ_NR];
arp_func_t ap_arp_func;
acc_t *ap_sendpkt;
acc_t *ap_sendlist;
acc_t *ap_reclist;
event_t ap_event;
} arp_port_t;
#define APF_EMPTY 0x00
#define APF_ARP_RD_IP 0x01
#define APF_ARP_RD_SP 0x02
#define APF_ARP_WR_IP 0x04
#define APF_ARP_WR_SP 0x08
#define APF_INADDR_SET 0x10
#define APF_SUSPEND 0x20
#define APS_INITIAL 1
#define APS_GETADDR 2
#define APS_ARPSTART 3
#define APS_ARPPROTO 4
#define APS_ARPMAIN 5
#define APS_ERROR 6
typedef struct arp_cache
{
int ac_flags;
int ac_state;
ether_addr_t ac_ethaddr;
ipaddr_t ac_ipaddr;
arp_port_t *ac_port;
time_t ac_expire;
time_t ac_lastuse;
} arp_cache_t;
#define ACF_EMPTY 0
#define ACF_PERM 1
#define ACF_PUB 2
#define ACS_UNUSED 0
#define ACS_INCOMPLETE 1
#define ACS_VALID 2
#define ACS_UNREACHABLE 3
static struct arp_hash_ent
{
arp_cache_t *ahe_row[ARP_HASH_WIDTH];
} arp_hash[ARP_HASH_NR];
static arp_port_t *arp_port_table;
static arp_cache_t *arp_cache;
static int arp_cache_nr;
static acc_t *arp_getdata ARGS(( int fd, size_t offset,
size_t count, int for_ioctl ));
static int arp_putdata ARGS(( int fd, size_t offset,
acc_t *data, int for_ioctl ));
static void arp_main ARGS(( arp_port_t *arp_port ));
static void arp_timeout ARGS(( int ref, timer_t *timer ));
static void setup_write ARGS(( arp_port_t *arp_port ));
static void setup_read ARGS(( arp_port_t *arp_port ));
static void do_reclist ARGS(( event_t *ev, ev_arg_t ev_arg ));
static void process_arp_pkt ARGS(( arp_port_t *arp_port, acc_t *data ));
static void client_reply ARGS(( arp_port_t *arp_port,
ipaddr_t ipaddr, ether_addr_t *ethaddr ));
static arp_cache_t *find_cache_ent ARGS(( arp_port_t *arp_port,
ipaddr_t ipaddr ));
static arp_cache_t *alloc_cache_ent ARGS(( int flags ));
static void arp_buffree ARGS(( int priority ));
#ifdef BUF_CONSISTENCY_CHECK
static void arp_bufcheck ARGS(( void ));
#endif
void arp_prep()
{
arp_port_table= alloc(eth_conf_nr * sizeof(arp_port_table[0]));
arp_cache_nr= ARP_CACHE_NR;
if (arp_cache_nr < (eth_conf_nr+1)*AP_REQ_NR)
{
arp_cache_nr= (eth_conf_nr+1)*AP_REQ_NR;
printf("arp: using %d cache entries instead of %d\n",
arp_cache_nr, ARP_CACHE_NR);
}
arp_cache= alloc(arp_cache_nr * sizeof(arp_cache[0]));
}
void arp_init()
{
arp_port_t *arp_port;
arp_cache_t *cache;
int i;
assert (BUF_S >= sizeof(struct nwio_ethstat));
assert (BUF_S >= sizeof(struct nwio_ethopt));
assert (BUF_S >= sizeof(arp46_t));
for (i=0, arp_port= arp_port_table; i<eth_conf_nr; i++, arp_port++)
{
arp_port->ap_state= APS_ERROR; /* Mark all ports as
* unavailable */
}
cache= arp_cache;
for (i=0; i<arp_cache_nr; i++, cache++)
{
cache->ac_state= ACS_UNUSED;
cache->ac_flags= ACF_EMPTY;
cache->ac_expire= 0;
cache->ac_lastuse= 0;
}
#ifndef BUF_CONSISTENCY_CHECK
bf_logon(arp_buffree);
#else
bf_logon(arp_buffree, arp_bufcheck);
#endif
}
static void arp_main(arp_port)
arp_port_t *arp_port;
{
int result;
switch (arp_port->ap_state)
{
case APS_INITIAL:
arp_port->ap_eth_fd= eth_open(arp_port->ap_eth_port,
arp_port->ap_eth_port, arp_getdata, arp_putdata,
0 /* no put_pkt */, 0 /* no select_res */);
if (arp_port->ap_eth_fd<0)
{
DBLOCK(1, printf("arp[%d]: unable to open eth[%d]\n",
arp_port-arp_port_table,
arp_port->ap_eth_port));
return;
}
arp_port->ap_state= APS_GETADDR;
result= eth_ioctl (arp_port->ap_eth_fd, NWIOGETHSTAT);
if ( result == NW_SUSPEND)
{
arp_port->ap_flags |= APF_SUSPEND;
return;
}
assert(result == NW_OK);
/* fall through */
case APS_GETADDR:
/* Wait for IP address */
if (!(arp_port->ap_flags & APF_INADDR_SET))
return;
/* fall through */
case APS_ARPSTART:
arp_port->ap_state= APS_ARPPROTO;
result= eth_ioctl (arp_port->ap_eth_fd, NWIOSETHOPT);
if (result==NW_SUSPEND)
{
arp_port->ap_flags |= APF_SUSPEND;
return;
}
assert(result == NW_OK);
/* fall through */
case APS_ARPPROTO:
arp_port->ap_state= APS_ARPMAIN;
setup_write(arp_port);
setup_read(arp_port);
return;
default:
ip_panic((
"arp_main(&arp_port_table[%d]) called but ap_state=0x%x\n",
arp_port->ap_eth_port, arp_port->ap_state ));
}
}
static acc_t *arp_getdata (fd, offset, count, for_ioctl)
int fd;
size_t offset;
size_t count;
int for_ioctl;
{
arp_port_t *arp_port;
acc_t *data;
int result;
arp_port= &arp_port_table[fd];
switch (arp_port->ap_state)
{
case APS_ARPPROTO:
if (!count)
{
result= (int)offset;
if (result<0)
{
arp_port->ap_state= APS_ERROR;
break;
}
if (arp_port->ap_flags & APF_SUSPEND)
{
arp_port->ap_flags &= ~APF_SUSPEND;
arp_main(arp_port);
}
return NW_OK;
}
assert ((!offset) && (count == sizeof(struct nwio_ethopt)));
{
struct nwio_ethopt *ethopt;
acc_t *acc;
acc= bf_memreq(sizeof(*ethopt));
ethopt= (struct nwio_ethopt *)ptr2acc_data(acc);
ethopt->nweo_flags= NWEO_COPY|NWEO_EN_BROAD|
NWEO_TYPESPEC;
ethopt->nweo_type= HTONS(ETH_ARP_PROTO);
return acc;
}
case APS_ARPMAIN:
assert (arp_port->ap_flags & APF_ARP_WR_IP);
if (!count)
{
data= arp_port->ap_sendpkt;
arp_port->ap_sendpkt= NULL;
assert(data);
bf_afree(data); data= NULL;
result= (int)offset;
if (result<0)
{
DIFBLOCK(1, (result != NW_SUSPEND),
printf(
"arp[%d]: write error on port %d: error %d\n",
fd, arp_port->ap_eth_fd, result));
arp_port->ap_state= APS_ERROR;
break;
}
arp_port->ap_flags &= ~APF_ARP_WR_IP;
if (arp_port->ap_flags & APF_ARP_WR_SP)
setup_write(arp_port);
return NW_OK;
}
assert (offset+count <= sizeof(arp46_t));
data= arp_port->ap_sendpkt;
assert(data);
data= bf_cut(data, offset, count);
return data;
default:
printf("arp_getdata(%d, 0x%d, 0x%d) called but ap_state=0x%x\n",
fd, offset, count, arp_port->ap_state);
break;
}
return 0;
}
static int arp_putdata (fd, offset, data, for_ioctl)
int fd;
size_t offset;
acc_t *data;
int for_ioctl;
{
arp_port_t *arp_port;
int result;
struct nwio_ethstat *ethstat;
ev_arg_t ev_arg;
acc_t *tmpacc;
arp_port= &arp_port_table[fd];
if (arp_port->ap_flags & APF_ARP_RD_IP)
{
if (!data)
{
result= (int)offset;
if (result<0)
{
DIFBLOCK(1, (result != NW_SUSPEND), printf(
"arp[%d]: read error on port %d: error %d\n",
fd, arp_port->ap_eth_fd, result));
return NW_OK;
}
if (arp_port->ap_flags & APF_ARP_RD_SP)
{
arp_port->ap_flags &= ~(APF_ARP_RD_IP|
APF_ARP_RD_SP);
setup_read(arp_port);
}
else
arp_port->ap_flags &= ~(APF_ARP_RD_IP|
APF_ARP_RD_SP);
return NW_OK;
}
assert (!offset);
/* Warning: the above assertion is illegal; puts and gets of
data can be brokenup in any piece the server likes. However
we assume that the server is eth.c and it transfers only
whole packets.
*/
data= bf_packIffLess(data, sizeof(arp46_t));
if (data->acc_length >= sizeof(arp46_t))
{
if (!arp_port->ap_reclist)
{
ev_arg.ev_ptr= arp_port;
ev_enqueue(&arp_port->ap_event, do_reclist,
ev_arg);
}
if (data->acc_linkC != 1)
{
tmpacc= bf_dupacc(data);
bf_afree(data);
data= tmpacc;
tmpacc= NULL;
}
data->acc_ext_link= arp_port->ap_reclist;
arp_port->ap_reclist= data;
}
else
bf_afree(data);
return NW_OK;
}
switch (arp_port->ap_state)
{
case APS_GETADDR:
if (!data)
{
result= (int)offset;
if (result<0)
{
arp_port->ap_state= APS_ERROR;
break;
}
if (arp_port->ap_flags & APF_SUSPEND)
{
arp_port->ap_flags &= ~APF_SUSPEND;
arp_main(arp_port);
}
return NW_OK;
}
compare (bf_bufsize(data), ==, sizeof(*ethstat));
data= bf_packIffLess(data, sizeof(*ethstat));
compare (data->acc_length, ==, sizeof(*ethstat));
ethstat= (struct nwio_ethstat *)ptr2acc_data(data);
arp_port->ap_ethaddr= ethstat->nwes_addr;
bf_afree(data);
return NW_OK;
default:
printf("arp_putdata(%d, 0x%d, 0x%lx) called but ap_state=0x%x\n",
fd, offset, (unsigned long)data, arp_port->ap_state);
break;
}
return EGENERIC;
}
static void setup_read(arp_port)
arp_port_t *arp_port;
{
int result;
while (!(arp_port->ap_flags & APF_ARP_RD_IP))
{
arp_port->ap_flags |= APF_ARP_RD_IP;
result= eth_read (arp_port->ap_eth_fd, ETH_MAX_PACK_SIZE);
if (result == NW_SUSPEND)
{
arp_port->ap_flags |= APF_ARP_RD_SP;
return;
}
DIFBLOCK(1, (result != NW_OK),
printf("arp[%d]: eth_read(..,%d)=%d\n",
arp_port-arp_port_table, ETH_MAX_PACK_SIZE, result));
}
}
static void setup_write(arp_port)
arp_port_t *arp_port;
{
int result;
acc_t *data;
for(;;)
{
data= arp_port->ap_sendlist;
if (!data)
break;
arp_port->ap_sendlist= data->acc_ext_link;
if (arp_port->ap_ipaddr == HTONL(0x00000000))
{
/* Interface is down */
printf(
"arp[%d]: not sending ARP packet, interface is down\n",
arp_port-arp_port_table);
bf_afree(data); data= NULL;
continue;
}
assert(!arp_port->ap_sendpkt);
arp_port->ap_sendpkt= data; data= NULL;
arp_port->ap_flags= (arp_port->ap_flags & ~APF_ARP_WR_SP) |
APF_ARP_WR_IP;
result= eth_write(arp_port->ap_eth_fd, sizeof(arp46_t));
if (result == NW_SUSPEND)
{
arp_port->ap_flags |= APF_ARP_WR_SP;
break;
}
if (result<0)
{
DIFBLOCK(1, (result != NW_SUSPEND),
printf("arp[%d]: eth_write(..,%d)=%d\n",
arp_port-arp_port_table, sizeof(arp46_t),
result));
return;
}
}
}
static void do_reclist(ev, ev_arg)
event_t *ev;
ev_arg_t ev_arg;
{
arp_port_t *arp_port;
acc_t *data;
arp_port= ev_arg.ev_ptr;
assert(ev == &arp_port->ap_event);
while (data= arp_port->ap_reclist, data != NULL)
{
arp_port->ap_reclist= data->acc_ext_link;
process_arp_pkt(arp_port, data);
bf_afree(data);
}
}
static void process_arp_pkt (arp_port, data)
arp_port_t *arp_port;
acc_t *data;
{
int i, entry, do_reply;
arp46_t *arp;
u16_t *p;
arp_cache_t *ce, *cache;
struct arp_req *reqp;
time_t curr_time;
ipaddr_t spa, tpa;
curr_time= get_time();
arp= (arp46_t *)ptr2acc_data(data);
memcpy(&spa, arp->a46_spa, sizeof(ipaddr_t));
memcpy(&tpa, arp->a46_tpa, sizeof(ipaddr_t));
if (arp->a46_hdr != HTONS(ARP_ETHERNET) ||
arp->a46_hln != 6 ||
arp->a46_pro != HTONS(ETH_IP_PROTO) ||
arp->a46_pln != 4)
return;
if (arp_port->ap_ipaddr == HTONL(0x00000000))
{
/* Interface is down */
#if DEBUG
printf("arp[%d]: dropping ARP packet, interface is down\n",
arp_port-arp_port_table);
#endif
return;
}
ce= find_cache_ent(arp_port, spa);
cache= NULL; /* lint */
do_reply= 0;
if (arp->a46_op != HTONS(ARP_REQUEST))
; /* No need to reply */
else if (tpa == arp_port->ap_ipaddr)
do_reply= 1;
else
{
/* Look for a published entry */
cache= find_cache_ent(arp_port, tpa);
if (cache)
{
if (cache->ac_flags & ACF_PUB)
{
/* Published entry */
do_reply= 1;
}
else
{
/* Nothing to do */
cache= NULL;
}
}
}
if (ce == NULL)
{
if (!do_reply)
return;
DBLOCK(0x10, printf("arp[%d]: allocating entry for ",
arp_port-arp_port_table);
writeIpAddr(spa); printf("\n"));
ce= alloc_cache_ent(ACF_EMPTY);
ce->ac_flags= ACF_EMPTY;
ce->ac_state= ACS_VALID;
ce->ac_ethaddr= arp->a46_sha;
ce->ac_ipaddr= spa;
ce->ac_port= arp_port;
ce->ac_expire= curr_time+ARP_EXP_TIME;
ce->ac_lastuse= curr_time-ARP_INUSE_OFFSET; /* never used */
}
if (ce->ac_state == ACS_INCOMPLETE || ce->ac_state == ACS_UNREACHABLE)
{
ce->ac_ethaddr= arp->a46_sha;
if (ce->ac_state == ACS_INCOMPLETE)
{
/* Find request entry */
entry= ce-arp_cache;
for (i= 0, reqp= arp_port->ap_req; i<AP_REQ_NR;
i++, reqp++)
{
if (reqp->ar_entry == entry)
break;
}
assert(i < AP_REQ_NR);
clck_untimer(&reqp->ar_timer);
reqp->ar_entry= -1;
ce->ac_state= ACS_VALID;
client_reply(arp_port, spa, &arp->a46_sha);
}
else
ce->ac_state= ACS_VALID;
}
/* Update fields in the arp cache. */
if (memcmp(&ce->ac_ethaddr, &arp->a46_sha,
sizeof(ce->ac_ethaddr)) != 0)
{
printf("arp[%d]: ethernet address for IP address ",
arp_port-arp_port_table);
writeIpAddr(spa);
printf(" changed from ");
writeEtherAddr(&ce->ac_ethaddr);
printf(" to ");
writeEtherAddr(&arp->a46_sha);
printf("\n");
ce->ac_ethaddr= arp->a46_sha;
}
ce->ac_expire= curr_time+ARP_EXP_TIME;
if (do_reply)
{
data= bf_memreq(sizeof(arp46_t));
arp= (arp46_t *)ptr2acc_data(data);
/* Clear padding */
assert(sizeof(arp->a46_data.a46_dummy) % sizeof(*p) == 0);
for (i= 0, p= (u16_t *)arp->a46_data.a46_dummy;
i < sizeof(arp->a46_data.a46_dummy)/sizeof(*p);
i++, p++)
{
*p= 0xdead;
}
arp->a46_dstaddr= ce->ac_ethaddr;
arp->a46_hdr= HTONS(ARP_ETHERNET);
arp->a46_pro= HTONS(ETH_IP_PROTO);
arp->a46_hln= 6;
arp->a46_pln= 4;
arp->a46_op= htons(ARP_REPLY);
if (tpa == arp_port->ap_ipaddr)
{
arp->a46_sha= arp_port->ap_ethaddr;
}
else
{
assert(cache);
arp->a46_sha= cache->ac_ethaddr;
}
memcpy (arp->a46_spa, &tpa, sizeof(ipaddr_t));
arp->a46_tha= ce->ac_ethaddr;
memcpy (arp->a46_tpa, &ce->ac_ipaddr, sizeof(ipaddr_t));
assert(data->acc_linkC == 1);
data->acc_ext_link= arp_port->ap_sendlist;
arp_port->ap_sendlist= data; data= NULL;
if (!(arp_port->ap_flags & APF_ARP_WR_IP))
setup_write(arp_port);
}
}
static void client_reply (arp_port, ipaddr, ethaddr)
arp_port_t *arp_port;
ipaddr_t ipaddr;
ether_addr_t *ethaddr;
{
(*arp_port->ap_arp_func)(arp_port->ap_ip_port, ipaddr, ethaddr);
}
static arp_cache_t *find_cache_ent (arp_port, ipaddr)
arp_port_t *arp_port;
ipaddr_t ipaddr;
{
arp_cache_t *ce;
int i;
unsigned hash;
hash= (ipaddr >> 24) ^ (ipaddr >> 16) ^ (ipaddr >> 8) ^ ipaddr;
hash &= ARP_HASH_MASK;
ce= arp_hash[hash].ahe_row[0];
if (ce && ce->ac_ipaddr == ipaddr && ce->ac_port == arp_port &&
ce->ac_state != ACS_UNUSED)
{
return ce;
}
for (i= 1; i<ARP_HASH_WIDTH; i++)
{
ce= arp_hash[hash].ahe_row[i];
if (!ce || ce->ac_ipaddr != ipaddr || ce->ac_port != arp_port
|| ce->ac_state == ACS_UNUSED)
{
continue;
}
arp_hash[hash].ahe_row[i]= arp_hash[hash].ahe_row[0];
arp_hash[hash].ahe_row[0]= ce;
return ce;
}
for (i=0, ce= arp_cache; i<arp_cache_nr; i++, ce++)
{
if (ce->ac_state != ACS_UNUSED &&
ce->ac_port == arp_port &&
ce->ac_ipaddr == ipaddr)
{
for (i= ARP_HASH_WIDTH-1; i>0; i--)
{
arp_hash[hash].ahe_row[i]=
arp_hash[hash].ahe_row[i-1];
}
assert(i == 0);
arp_hash[hash].ahe_row[0]= ce;
return ce;
}
}
return NULL;
}
static arp_cache_t *alloc_cache_ent(flags)
int flags;
{
arp_cache_t *cache, *old;
int i;
old= NULL;
for (i=0, cache= arp_cache; i<arp_cache_nr; i++, cache++)
{
if (cache->ac_state == ACS_UNUSED)
{
old= cache;
break;
}
if (cache->ac_state == ACS_INCOMPLETE)
continue;
if (cache->ac_flags & ACF_PERM)
continue;
if (!old || cache->ac_lastuse < old->ac_lastuse)
old= cache;
}
assert(old);
if (!flags)
return old;
/* Get next permanent entry */
for (i=0, cache= arp_cache; i<arp_cache_nr; i++, cache++)
{
if (cache->ac_state == ACS_UNUSED)
break;
if (cache->ac_flags & ACF_PERM)
continue;
break;
}
if (i >= arp_cache_nr/2)
return NULL; /* Too many entries */
if (cache != old)
{
assert(old > cache);
*old= *cache;
old= cache;
}
if (!(flags & ACF_PUB))
return old;
/* Get first nonpublished entry */
for (i=0, cache= arp_cache; i<arp_cache_nr; i++, cache++)
{
if (cache->ac_state == ACS_UNUSED)
break;
if (cache->ac_flags & ACF_PUB)
continue;
break;
}
if (cache != old)
{
assert(old > cache);
*old= *cache;
old= cache;
}
return old;
}
void arp_set_ipaddr (eth_port, ipaddr)
int eth_port;
ipaddr_t ipaddr;
{
arp_port_t *arp_port;
if (eth_port < 0 || eth_port >= eth_conf_nr)
return;
arp_port= &arp_port_table[eth_port];
arp_port->ap_ipaddr= ipaddr;
arp_port->ap_flags |= APF_INADDR_SET;
arp_port->ap_flags &= ~APF_SUSPEND;
if (arp_port->ap_state == APS_GETADDR)
arp_main(arp_port);
}
int arp_set_cb(eth_port, ip_port, arp_func)
int eth_port;
int ip_port;
arp_func_t arp_func;
{
int i;
arp_port_t *arp_port;
assert(eth_port >= 0);
if (eth_port >= eth_conf_nr)
return ENXIO;
arp_port= &arp_port_table[eth_port];
arp_port->ap_eth_port= eth_port;
arp_port->ap_ip_port= ip_port;
arp_port->ap_state= APS_INITIAL;
arp_port->ap_flags= APF_EMPTY;
arp_port->ap_arp_func= arp_func;
arp_port->ap_sendpkt= NULL;
arp_port->ap_sendlist= NULL;
arp_port->ap_reclist= NULL;
for (i= 0; i<AP_REQ_NR; i++) {
arp_port->ap_req[i].ar_entry= -1;
arp_port->ap_req[i].ar_timer.tim_active= 0;
}
ev_init(&arp_port->ap_event);
arp_main(arp_port);
return NW_OK;
}
int arp_ip_eth (eth_port, ipaddr, ethaddr)
int eth_port;
ipaddr_t ipaddr;
ether_addr_t *ethaddr;
{
int i, ref;
arp_port_t *arp_port;
struct arp_req *reqp;
arp_cache_t *ce;
time_t curr_time;
assert(eth_port >= 0 && eth_port < eth_conf_nr);
arp_port= &arp_port_table[eth_port];
assert(arp_port->ap_state == APS_ARPMAIN ||
(printf("arp[%d]: ap_state= %d\n", arp_port-arp_port_table,
arp_port->ap_state), 0));
curr_time= get_time();
ce= find_cache_ent (arp_port, ipaddr);
if (ce && ce->ac_expire < curr_time)
{
assert(ce->ac_state != ACS_INCOMPLETE);
/* Check whether there is enough space for an ARP
* request or not.
*/
for (i= 0, reqp= arp_port->ap_req; i<AP_REQ_NR; i++, reqp++)
{
if (reqp->ar_entry < 0)
break;
}
if (i < AP_REQ_NR)
{
/* Okay, expire this entry. */
ce->ac_state= ACS_UNUSED;
ce= NULL;
}
else
{
/* Continue using this entry for a while */
printf("arp[%d]: Overloaded! Keeping entry for ",
arp_port-arp_port_table);
writeIpAddr(ipaddr);
printf("\n");
ce->ac_expire= curr_time+ARP_NOTRCH_EXP_TIME;
}
}
if (ce)
{
/* Found an entry. This entry should be valid, unreachable
* or incomplete.
*/
ce->ac_lastuse= curr_time;
if (ce->ac_state == ACS_VALID)
{
*ethaddr= ce->ac_ethaddr;
return NW_OK;
}
if (ce->ac_state == ACS_UNREACHABLE)
return EHOSTUNREACH;
assert(ce->ac_state == ACS_INCOMPLETE);
return NW_SUSPEND;
}
/* Find an empty slot for an ARP request */
for (i= 0, reqp= arp_port->ap_req; i<AP_REQ_NR; i++, reqp++)
{
if (reqp->ar_entry < 0)
break;
}
if (i >= AP_REQ_NR)
{
/* We should be able to report that this ARP request
* cannot be accepted. At the moment we just return SUSPEND.
*/
return NW_SUSPEND;
}
ref= (eth_port*AP_REQ_NR + i);
ce= alloc_cache_ent(ACF_EMPTY);
ce->ac_flags= 0;
ce->ac_state= ACS_INCOMPLETE;
ce->ac_ipaddr= ipaddr;
ce->ac_port= arp_port;
ce->ac_expire= curr_time+ARP_EXP_TIME;
ce->ac_lastuse= curr_time;
reqp->ar_entry= ce-arp_cache;
reqp->ar_req_count= -1;
/* Send the first packet by expiring the timer */
clck_timer(&reqp->ar_timer, 1, arp_timeout, ref);
return NW_SUSPEND;
}
int arp_ioctl (eth_port, fd, req, get_userdata, put_userdata)
int eth_port;
int fd;
ioreq_t req;
get_userdata_t get_userdata;
put_userdata_t put_userdata;
{
arp_port_t *arp_port;
arp_cache_t *ce, *cache;
acc_t *data;
nwio_arp_t *arp_iop;
int entno, result, ac_flags;
u32_t flags;
ipaddr_t ipaddr;
time_t curr_time;
assert(eth_port >= 0 && eth_port < eth_conf_nr);
arp_port= &arp_port_table[eth_port];
assert(arp_port->ap_state == APS_ARPMAIN ||
(printf("arp[%d]: ap_state= %d\n", arp_port-arp_port_table,
arp_port->ap_state), 0));
switch(req)
{
case NWIOARPGIP:
data= (*get_userdata)(fd, 0, sizeof(*arp_iop), TRUE);
if (data == NULL)
return EFAULT;
data= bf_packIffLess(data, sizeof(*arp_iop));
arp_iop= (nwio_arp_t *)ptr2acc_data(data);
ipaddr= arp_iop->nwa_ipaddr;
ce= NULL; /* lint */
for (entno= 0; entno < arp_cache_nr; entno++)
{
ce= &arp_cache[entno];
if (ce->ac_state == ACS_UNUSED ||
ce->ac_port != arp_port)
{
continue;
}
if (ce->ac_ipaddr == ipaddr)
break;
}
if (entno == arp_cache_nr)
{
/* Also report the address of this interface */
if (ipaddr != arp_port->ap_ipaddr)
{
bf_afree(data);
return ENOENT;
}
arp_iop->nwa_entno= arp_cache_nr;
arp_iop->nwa_ipaddr= ipaddr;
arp_iop->nwa_ethaddr= arp_port->ap_ethaddr;
arp_iop->nwa_flags= NWAF_PERM | NWAF_PUB;
}
else
{
arp_iop->nwa_entno= entno+1;
arp_iop->nwa_ipaddr= ce->ac_ipaddr;
arp_iop->nwa_ethaddr= ce->ac_ethaddr;
arp_iop->nwa_flags= 0;
if (ce->ac_state == ACS_INCOMPLETE)
arp_iop->nwa_flags |= NWAF_INCOMPLETE;
if (ce->ac_state == ACS_UNREACHABLE)
arp_iop->nwa_flags |= NWAF_DEAD;
if (ce->ac_flags & ACF_PERM)
arp_iop->nwa_flags |= NWAF_PERM;
if (ce->ac_flags & ACF_PUB)
arp_iop->nwa_flags |= NWAF_PUB;
}
result= (*put_userdata)(fd, 0, data, TRUE);
return result;
case NWIOARPGNEXT:
data= (*get_userdata)(fd, 0, sizeof(*arp_iop), TRUE);
if (data == NULL)
return EFAULT;
data= bf_packIffLess(data, sizeof(*arp_iop));
arp_iop= (nwio_arp_t *)ptr2acc_data(data);
entno= arp_iop->nwa_entno;
if (entno < 0)
entno= 0;
ce= NULL; /* lint */
for (; entno < arp_cache_nr; entno++)
{
ce= &arp_cache[entno];
if (ce->ac_state == ACS_UNUSED ||
ce->ac_port != arp_port)
{
continue;
}
break;
}
if (entno == arp_cache_nr)
{
bf_afree(data);
return ENOENT;
}
arp_iop->nwa_entno= entno+1;
arp_iop->nwa_ipaddr= ce->ac_ipaddr;
arp_iop->nwa_ethaddr= ce->ac_ethaddr;
arp_iop->nwa_flags= 0;
if (ce->ac_state == ACS_INCOMPLETE)
arp_iop->nwa_flags |= NWAF_INCOMPLETE;
if (ce->ac_state == ACS_UNREACHABLE)
arp_iop->nwa_flags |= NWAF_DEAD;
if (ce->ac_flags & ACF_PERM)
arp_iop->nwa_flags |= NWAF_PERM;
if (ce->ac_flags & ACF_PUB)
arp_iop->nwa_flags |= NWAF_PUB;
result= (*put_userdata)(fd, 0, data, TRUE);
return result;
case NWIOARPSIP:
data= (*get_userdata)(fd, 0, sizeof(*arp_iop), TRUE);
if (data == NULL)
return EFAULT;
data= bf_packIffLess(data, sizeof(*arp_iop));
arp_iop= (nwio_arp_t *)ptr2acc_data(data);
ipaddr= arp_iop->nwa_ipaddr;
if (find_cache_ent(arp_port, ipaddr))
{
bf_afree(data);
return EEXIST;
}
flags= arp_iop->nwa_flags;
ac_flags= ACF_EMPTY;
if (flags & NWAF_PERM)
ac_flags |= ACF_PERM;
if (flags & NWAF_PUB)
ac_flags |= ACF_PUB|ACF_PERM;
/* Allocate a cache entry */
ce= alloc_cache_ent(ac_flags);
if (ce == NULL)
{
bf_afree(data);
return ENOMEM;
}
ce->ac_flags= ac_flags;
ce->ac_state= ACS_VALID;
ce->ac_ethaddr= arp_iop->nwa_ethaddr;
ce->ac_ipaddr= arp_iop->nwa_ipaddr;
ce->ac_port= arp_port;
curr_time= get_time();
ce->ac_expire= curr_time+ARP_EXP_TIME;
ce->ac_lastuse= curr_time;
bf_afree(data);
return 0;
case NWIOARPDIP:
data= (*get_userdata)(fd, 0, sizeof(*arp_iop), TRUE);
if (data == NULL)
return EFAULT;
data= bf_packIffLess(data, sizeof(*arp_iop));
arp_iop= (nwio_arp_t *)ptr2acc_data(data);
ipaddr= arp_iop->nwa_ipaddr;
bf_afree(data); data= NULL;
ce= find_cache_ent(arp_port, ipaddr);
if (!ce)
return ENOENT;
if (ce->ac_state == ACS_INCOMPLETE)
return EINVAL;
ac_flags= ce->ac_flags;
if (ac_flags & ACF_PUB)
{
/* Make sure entry is at the end of published
* entries.
*/
for (entno= 0, cache= arp_cache;
entno<arp_cache_nr; entno++, cache++)
{
if (cache->ac_state == ACS_UNUSED)
break;
if (cache->ac_flags & ACF_PUB)
continue;
break;
}
assert(cache > arp_cache);
cache--;
if (cache != ce)
{
assert(cache > ce);
*ce= *cache;
ce= cache;
}
}
if (ac_flags & ACF_PERM)
{
/* Make sure entry is at the end of permanent
* entries.
*/
for (entno= 0, cache= arp_cache;
entno<arp_cache_nr; entno++, cache++)
{
if (cache->ac_state == ACS_UNUSED)
break;
if (cache->ac_flags & ACF_PERM)
continue;
break;
}
assert(cache > arp_cache);
cache--;
if (cache != ce)
{
assert(cache > ce);
*ce= *cache;
ce= cache;
}
}
/* Clear entry */
ce->ac_state= ACS_UNUSED;
return 0;
default:
ip_panic(("arp_ioctl: unknown request 0x%lx",
(unsigned long)req));
}
return 0;
}
static void arp_timeout (ref, timer)
int ref;
timer_t *timer;
{
int i, port, reqind, acind;
arp_port_t *arp_port;
arp_cache_t *ce;
struct arp_req *reqp;
time_t curr_time;
acc_t *data;
arp46_t *arp;
u16_t *p;
port= ref / AP_REQ_NR;
reqind= ref % AP_REQ_NR;
assert(port >= 0 && port <eth_conf_nr);
arp_port= &arp_port_table[port];
reqp= &arp_port->ap_req[reqind];
assert (timer == &reqp->ar_timer);
acind= reqp->ar_entry;
assert(acind >= 0 && acind < arp_cache_nr);
ce= &arp_cache[acind];
assert(ce->ac_port == arp_port);
assert(ce->ac_state == ACS_INCOMPLETE);
if (++reqp->ar_req_count >= MAX_ARP_RETRIES)
{
curr_time= get_time();
ce->ac_state= ACS_UNREACHABLE;
ce->ac_expire= curr_time+ ARP_NOTRCH_EXP_TIME;
ce->ac_lastuse= curr_time;
clck_untimer(&reqp->ar_timer);
reqp->ar_entry= -1;
client_reply(arp_port, ce->ac_ipaddr, NULL);
return;
}
data= bf_memreq(sizeof(arp46_t));
arp= (arp46_t *)ptr2acc_data(data);
/* Clear padding */
assert(sizeof(arp->a46_data.a46_dummy) % sizeof(*p) == 0);
for (i= 0, p= (u16_t *)arp->a46_data.a46_dummy;
i < sizeof(arp->a46_data.a46_dummy)/sizeof(*p);
i++, p++)
{
*p= 0xdead;
}
arp->a46_dstaddr.ea_addr[0]= 0xff;
arp->a46_dstaddr.ea_addr[1]= 0xff;
arp->a46_dstaddr.ea_addr[2]= 0xff;
arp->a46_dstaddr.ea_addr[3]= 0xff;
arp->a46_dstaddr.ea_addr[4]= 0xff;
arp->a46_dstaddr.ea_addr[5]= 0xff;
arp->a46_hdr= HTONS(ARP_ETHERNET);
arp->a46_pro= HTONS(ETH_IP_PROTO);
arp->a46_hln= 6;
arp->a46_pln= 4;
arp->a46_op= HTONS(ARP_REQUEST);
arp->a46_sha= arp_port->ap_ethaddr;
memcpy (arp->a46_spa, &arp_port->ap_ipaddr, sizeof(ipaddr_t));
memset(&arp->a46_tha, '\0', sizeof(ether_addr_t));
memcpy (arp->a46_tpa, &ce->ac_ipaddr, sizeof(ipaddr_t));
assert(data->acc_linkC == 1);
data->acc_ext_link= arp_port->ap_sendlist;
arp_port->ap_sendlist= data; data= NULL;
if (!(arp_port->ap_flags & APF_ARP_WR_IP))
setup_write(arp_port);
clck_timer(&reqp->ar_timer, get_time() + ARP_TIMEOUT,
arp_timeout, ref);
}
static void arp_buffree(priority)
int priority;
{
int i;
acc_t *pack, *next_pack;
arp_port_t *arp_port;
for (i= 0, arp_port= arp_port_table; i<eth_conf_nr; i++, arp_port++)
{
if (priority == ARP_PRI_REC)
{
next_pack= arp_port->ap_reclist;
while(next_pack && next_pack->acc_ext_link)
{
pack= next_pack;
next_pack= pack->acc_ext_link;
bf_afree(pack);
}
if (next_pack)
{
if (ev_in_queue(&arp_port->ap_event))
{
DBLOCK(1, printf(
"not freeing ap_reclist, ap_event enqueued\n"));
}
else
{
bf_afree(next_pack);
next_pack= NULL;
}
}
arp_port->ap_reclist= next_pack;
}
if (priority == ARP_PRI_SEND)
{
next_pack= arp_port->ap_sendlist;
while(next_pack && next_pack->acc_ext_link)
{
pack= next_pack;
next_pack= pack->acc_ext_link;
bf_afree(pack);
}
if (next_pack)
{
if (ev_in_queue(&arp_port->ap_event))
{
DBLOCK(1, printf(
"not freeing ap_sendlist, ap_event enqueued\n"));
}
else
{
bf_afree(next_pack);
next_pack= NULL;
}
}
arp_port->ap_sendlist= next_pack;
}
}
}
#ifdef BUF_CONSISTENCY_CHECK
static void arp_bufcheck()
{
int i;
arp_port_t *arp_port;
acc_t *pack;
for (i= 0, arp_port= arp_port_table; i<eth_conf_nr; i++, arp_port++)
{
for (pack= arp_port->ap_reclist; pack;
pack= pack->acc_ext_link)
{
bf_check_acc(pack);
}
for (pack= arp_port->ap_sendlist; pack;
pack= pack->acc_ext_link)
{
bf_check_acc(pack);
}
}
}
#endif /* BUF_CONSISTENCY_CHECK */
/*
* $PchId: arp.c,v 1.22 2005/06/28 14:15:06 philip Exp $
*/