uint_t
icmp_input (T_NET_BUF **inputp, uint_t *offp, uint_t *nextp)
{
T_NET_BUF *input = *inputp;
T_ICMP4_HDR *icmp4h;
T_IN4_ADDR addr;
uint_t len, align;
NET_COUNT_ICMP4(net_count_icmp4.in_octets,
input->len - GET_IF_IP4_HDR_SIZE(input));
NET_COUNT_ICMP4(net_count_icmp4.in_packets, 1);
/* ICMP ヘッダの長さをチェックする。*/
if (input->len < IF_IP4_ICMP4_HDR_SIZE) {
NET_COUNT_ICMP4(net_count_icmp4.in_err_packets, 1);
NET_COUNT_MIB(icmp_stats.icmpInErrors, 1);
goto buf_rel;
}
icmp4h = (T_ICMP4_HDR *)(input->buf + *offp);
/* 4 オクテット境界のデータ長 */
len = input->len - *offp;
align = (len + 3) >> 2 << 2;
/* 4 オクテット境界までパディングで埋める。*/
if (align > len)
memset((uint8_t*)input->buf + input->len, 0, (size_t)(align - len));
/* チェックサムを計算する。*/
if (in_cksum(icmp4h, align) != 0) {
NET_COUNT_ICMP4(net_count_icmp4.in_err_packets, 1);
goto buf_rel;
}
/* メッセージの型により分岐する。*/
switch (icmp4h->type) {
case ICMP4_ECHO_REQUEST:
icmp_echo(input, *offp);
return IPPROTO_DONE;
break;
case ICMP4_ECHO_REPLY:
#ifdef ICMP_CFG_CALLBACK_ECHO_REPLY
icmp_echo_reply(input, *offp);
#endif /* of #ifdef ICMP_CFG_CALLBACK_ECHO_REPLY */
break;
case ICMP4_UNREACH:
icmp_unreach(input, *offp);
break;
case ICMP4_REDIRECT:
#if NUM_REDIRECT_ROUTE_ENTRY > 0
addr = ntohl(icmp4h->data.addr);
syslog(LOG_INFO, "[ICMP] redirect, addr: %s.", ip2str(NULL, &addr));
icmp_redirect(input, *offp);
#else /* of #if NUM_REDIRECT_ROUTE_ENTRY > 0 */
addr = ntohl(icmp4h->data.addr);
syslog(LOG_INFO, "[ICMP] redirect ignored, addr: %s.", ip2str(NULL, &addr));
#endif /* of #if NUM_REDIRECT_ROUTE_ENTRY > 0 */
break;
default:
syslog(LOG_INFO, "[ICMP] unknown type: %d.", icmp4h->type);
NET_COUNT_ICMP4(net_count_icmp4.in_err_packets, 1);
break;
}
buf_rel:
syscall(rel_net_buf(input));
return IPPROTO_DONE;
}
/**
* Handler for incoming ICMP packets.
*/
void icmp_handler (const in_Header *ip, BOOL broadcast)
{
union ICMP_PKT *icmp;
const in_Header *orig_ip;
int type, code;
unsigned len;
DWORD delta_time;
BOOL for_me, i_orig; /* is it for me, did I originate it */
const char *msg;
DEBUG_RX (NULL, ip);
if (block_icmp) /* application is handling ICMP; not needed */
return;
len = in_GetHdrLen (ip);
icmp = (union ICMP_PKT*) ((BYTE*)ip + len);
len = intel16 (ip->length) - len;
for_me = _ip4_is_multihome_addr (intel(ip->destination));
if (!for_me || broadcast) /* drop broadcast pings.. */
return;
if (len < sizeof(icmp->info))
{
STAT (icmpstats.icps_tooshort++);
return;
}
if (CHECKSUM(icmp,len) != 0xFFFF)
{
STAT (icmpstats.icps_checksum++);
icmp_print (1, _LANG("bad checksum"), ip->source);
return;
}
type = icmp->unused.type;
code = icmp->unused.code;
orig_ip = &icmp->ip.ip;
i_orig = _ip4_is_local_addr (intel(orig_ip->source));
if (type == ICMP_MASKREPLY)
{
if (!_do_mask_req)
return;
i_orig = TRUE;
}
/* !! this needs work
*/
if (!i_orig &&
(type != ICMP_ECHOREPLY && type != ICMP_ECHO &&
type != ICMP_IREQREPLY && type != ICMP_TSTAMP))
{
icmp_bogus (ip, type, NULL);
return;
}
switch (type)
{
case ICMP_ECHOREPLY: /* check if we were waiting for it */
delta_time = set_timeout(0) - icmp->echo.identifier;
add_ping (intel(ip->source), delta_time, icmp->echo.index);
return;
case ICMP_UNREACH:
if (code < DIM(icmp_unreach_str))
{
UINT len_needed = 8 + in_GetHdrLen (orig_ip);
WORD next_mtu = 0;
msg = _LANG (icmp_unreach_str[code]);
icmp_print (1, msg, ip->source);
if (orig_ip->proto == TCP_PROTO ||
orig_ip->proto == UDP_PROTO)
len_needed += 4; /* Need the src/dest port numbers */
if (len >= len_needed)
{
if (code == ICMP_UNREACH_NEEDFRAG)
next_mtu = intel16 (icmp->needfrag.next_mtu);
#if !defined(USE_UDP_ONLY)
if (orig_ip->proto == TCP_PROTO)
_tcp_cancel (orig_ip, ICMP_UNREACH, code, msg, &next_mtu);
else
#endif
if (orig_ip->proto == UDP_PROTO)
_udp_cancel (orig_ip, ICMP_UNREACH, code, msg, &next_mtu);
/** \todo Handle cancelling raw sockets */
#if defined(USE_BSD_API) && 0
else
_raw_cancel (orig_ip, ICMP_UNREACH, code, msg);
#endif
}
else
STAT (icmpstats.icps_tooshort++);
}
else
STAT (icmpstats.icps_badcode++);
return;
case ICMP_SOURCEQUENCH:
#if !defined(USE_UDP_ONLY)
if (orig_ip->proto == TCP_PROTO)
{
msg = _LANG (icmp_type_str[type]);
icmp_print (1, msg, ip->source);
_tcp_cancel (orig_ip, ICMP_SOURCEQUENCH, code, msg, NULL);
}
#endif
return;
case ICMP_REDIRECT:
if (code < DIM(icmp_redirect_str))
icmp_redirect (icmp, ip, orig_ip, code);
else STAT (icmpstats.icps_badcode++);
return;
case ICMP_ECHO:
icmp_print (2, _LANG("PING requested of us"), ip->source);
icmp_echo_reply (ip, icmp, len);
return;
case ICMP_TIMXCEED:
if (code >= DIM(icmp_exceed_str))
{
STAT (icmpstats.icps_badcode++);
return;
}
if (code == 0) /* "TTL exceeded in transit" */
switch (orig_ip->proto)
{
#if !defined(USE_UDP_ONLY)
case TCP_PROTO:
msg = _LANG (icmp_exceed_str[0]);
icmp_print (1, msg, ip->source);
_tcp_cancel (orig_ip, ICMP_TIMXCEED, code, msg, NULL);
break;
#endif
case UDP_PROTO:
msg = _LANG (icmp_exceed_str[0]);
icmp_print (1, msg, ip->source);
_udp_cancel (orig_ip, ICMP_TIMXCEED, code, msg, NULL);
break;
}
return;
case ICMP_PARAMPROB:
msg = _LANG (icmp_type_str[ICMP_PARAMPROB]);
switch (orig_ip->proto)
{
#if !defined(USE_UDP_ONLY)
case TCP_PROTO:
icmp_print (0, msg, ip->source);
_tcp_cancel (orig_ip, ICMP_PARAMPROB, code, msg, NULL);
break;
#endif
case UDP_PROTO:
icmp_print (0, msg, ip->source);
_udp_cancel (orig_ip, ICMP_PARAMPROB, code, msg, NULL);
break;
}
return;
case ICMP_ROUTERADVERT: /* todo !! */
msg = _LANG (icmp_type_str[ICMP_ROUTERADVERT]);
icmp_print (1, msg, ip->source);
return;
case ICMP_ROUTERSOLICIT: /* todo !! */
msg = _LANG (icmp_type_str[ICMP_ROUTERSOLICIT]);
icmp_print (1, msg, ip->source);
return;
case ICMP_TSTAMP:
msg = _LANG (icmp_type_str[ICMP_TSTAMP]);
icmp_print (1, msg, ip->source);
/**< \todo send reply? */
return;
case ICMP_TSTAMPREPLY:
msg = _LANG (icmp_type_str[ICMP_TSTAMPREPLY]);
icmp_print (1, msg, ip->source);
/**< \todo should store */
return;
case ICMP_IREQ:
msg = _LANG (icmp_type_str[ICMP_IREQ]);
icmp_print (1, msg, ip->source);
/**< \todo send reply */
return;
case ICMP_IREQREPLY:
msg = _LANG (icmp_type_str[ICMP_IREQREPLY]);
icmp_print (1, msg, ip->source);
/**< \todo send reply upwards */
return;
case ICMP_MASKREQ:
/* might be sent by us, never answer */
break;
case ICMP_MASKREPLY:
msg = _LANG (icmp_type_str[ICMP_MASKREPLY]);
icmp_print (0, msg, ip->source);
if ((icmp->mask.identifier == addr_mask_id) &&
(icmp->mask.sequence == addr_mask_seq-1) &&
sin_mask != intel(icmp->mask.mask))
outsnl ("Conflicting net-mask from \"ICMP Addr Mask Reply\"\7");
addr_mask_id = 0;
return;
}
}