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[tcpip] Add IP statistics collection as per RFC 4293 

Signed-off-by: Michael Brown <mcb30@ipxe.org>
This commit is contained in:
Michael Brown 2014-03-02 20:33:35 +00:00
parent c165e8d1fc
commit 11963c4f5f
7 changed files with 296 additions and 22 deletions
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4
src/include/ipxe/fragment.h
View File

@ -27,6 +27,8 @@ struct fragment {
size_t hdrlen;
/** Reassembly timer */
struct retry_timer timer;
/** Fragment reassembler */
struct fragment_reassembler *fragments;
};
/** A fragment reassembler */
@ -59,6 +61,8 @@ struct fragment_reassembler {
* @ret more_frags More fragments exist
*/
int ( * more_fragments ) ( struct io_buffer *iobuf, size_t hdrlen );
/** Associated IP statistics */
struct ip_statistics *stats;
};
extern struct io_buffer *

187
src/include/ipxe/ipstat.h Normal file
View File

@ -0,0 +1,187 @@
#ifndef _IPXE_IPSTATS_H
#define _IPXE_IPSTATS_H
/** @file
*
* IP statistics
*
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <ipxe/tables.h>
struct io_buffer;
/** IP system statistics
*
* Definitions are taken from the RFC4293 section 5
* "ipSystemStatsEntry" table.
*
* To minimise code size, we use "unsigned long" as the counter
* variable type regardless of whether this type is 32-bit or 64-bit.
* On a 32-bit build (e.g. the standard BIOS build), this means that
* we omit the "high capacity" 64-bit counters (prefixed with "HC").
* This reduces the code size required to maintain the counter values,
* and avoids the need to support the "%lld" format in vsprintf.c
* (which would require dragging in the 64-bit division library on a
* standard 32-bit build). Since total available memory in a 32-bit
* environment is limited to 4GB, it is unlikely that we will overflow
* even the 32-bit octet counters under normal operation.
*
* Counters relating to packet forwarding are omitted, since iPXE
* includes no functionality for acting as a router.
*
* Counters related to output fragmentation are omitted, since iPXE
* has no support for fragmenting transmitted packets.
*
* The ipSystemStatsInDiscards and ipSystemStatsOutDiscards counters
* are omitted, since they will always be zero.
*
* Separate octet counters for multicast packets are omitted to save
* code size.
*/
struct ip_statistics {
/** ipSystemStatsInReceives
*
* The total number of input IP datagrams received, including
* those received in error.
*/
unsigned long in_receives;
/** ipSystemStatsInOctets
*
* The total number of octets received in input IP datagrams,
* including those received in error. Octets from datagrams
* counted in ipSystemStatsInReceives MUST be counted here.
*/
unsigned long in_octets;
/** ipSystemStatsInHdrErrors
*
* The number of input IP datagrams discarded due to errors in
* their IP headers, including version number mismatch, other
* format errors, hop count exceeded, errors discovered in
* processing their IP options, etc.
*/
unsigned long in_hdr_errors;
/** ipSystemStatsInAddrErrors
*
* The number of input IP datagrams discarded because the IP
* address in their IP header's destination field was not a
* valid address to be received at this entity. This count
* includes invalid addresses (e.g., ::0). For entities that
* are not IP routers and therefore do not forward datagrams,
* this counter includes datagrams discarded because the
* destination address was not a local address.
*/
unsigned long in_addr_errors;
/** ipSystemStatsInUnknownProtos
*
* The number of locally-addressed IP datagrams received
* successfully but discarded because of an unknown or
* unsupported protocol.
*/
unsigned long in_unknown_protos;
/** ipSystemStatsInTruncatedPkts
*
* The number of input IP datagrams discarded because the
* datagram frame didn't carry enough data.
*/
unsigned long in_truncated_pkts;
/** ipSystemStatsReasmReqds
*
* The number of IP fragments received that needed to be
* reassembled at this interface.
*/
unsigned long reasm_reqds;
/** ipSystemStatsReasmOks
*
* The number of IP datagrams successfully reassembled.
*/
unsigned long reasm_oks;
/** ipSystemStatsReasmFails
*
* The number of failures detected by the IP re-assembly
* algorithm (for whatever reason: timed out, errors, etc.).
* Note that this is not necessarily a count of discarded IP
* fragments since some algorithms (notably the algorithm in
* RFC 815) can lose track of the number of fragments by
* combining them as they are received.
*/
unsigned long reasm_fails;
/** ipSystemStatsInDelivers
*
* The total number of datagrams successfully delivered to IP
* user-protocols (including ICMP).
*/
unsigned long in_delivers;
/** ipSystemStatsOutRequests
*
* The total number of IP datagrams that local IP user-
* protocols (including ICMP) supplied to IP in requests for
* transmission.
*/
unsigned long out_requests;
/** ipSystemStatsOutNoRoutes
*
* The number of locally generated IP datagrams discarded
* because no route could be found to transmit them to their
* destination.
*/
unsigned long out_no_routes;
/** ipSystemStatsOutTransmits
*
* The total number of IP datagrams that this entity supplied
* to the lower layers for transmission. This includes
* datagrams generated locally and those forwarded by this
* entity.
*/
unsigned long out_transmits;
/** ipSystemStatsOutOctets
*
* The total number of octets in IP datagrams delivered to the
* lower layers for transmission. Octets from datagrams
* counted in ipSystemStatsOutTransmits MUST be counted here.
*/
unsigned long out_octets;
/** ipSystemStatsInMcastPkts
*
* The number of IP multicast datagrams received.
*/
unsigned long in_mcast_pkts;
/** ipSystemStatsOutMcastPkts
*
* The number of IP multicast datagrams transmitted.
*/
unsigned long out_mcast_pkts;
/** ipSystemStatsInBcastPkts
*
* The number of IP broadcast datagrams received.
*/
unsigned long in_bcast_pkts;
/** ipSystemStatsOutBcastPkts
*
* The number of IP broadcast datagrams transmitted.
*/
unsigned long out_bcast_pkts;
};
/** An IP system statistics family */
struct ip_statistics_family {
/** IP version */
unsigned int version;
/** Statistics */
struct ip_statistics *stats;
};
/** IP system statistics family table */
#define IP_STATISTICS_FAMILIES \
__table ( struct ip_statistics_family, "ip_statistics_families" )
/** Declare an IP system statistics family */
#define __ip_statistics_family( order ) \
__table_entry ( IP_STATISTICS_FAMILIES, order )
#define IP_STATISTICS_IPV4 01
#define IP_STATISTICS_IPV6 02
#endif /* _IPXE_IPSTATS_H */

4
src/include/ipxe/tcpip.h
View File

@ -17,6 +17,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
struct io_buffer;
struct net_device;
struct ip_statistics;
/** Empty checksum value
*
@ -132,7 +133,8 @@ struct tcpip_net_protocol {
extern int tcpip_rx ( struct io_buffer *iobuf, struct net_device *netdev,
uint8_t tcpip_proto, struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest, uint16_t pshdr_csum );
struct sockaddr_tcpip *st_dest, uint16_t pshdr_csum,
struct ip_statistics *stats );
extern int tcpip_tx ( struct io_buffer *iobuf, struct tcpip_protocol *tcpip,
struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest,

8
src/net/fragment.c
View File

@ -24,6 +24,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#include <string.h>
#include <ipxe/retry.h>
#include <ipxe/timer.h>
#include <ipxe/ipstat.h>
#include <ipxe/fragment.h>
/** @file
@ -45,6 +46,7 @@ static void fragment_expired ( struct retry_timer *timer, int fail __unused ) {
DBGC ( fragment, "FRAG %p expired\n", fragment );
free_iob ( fragment->iobuf );
list_del ( &fragment->list );
fragment->fragments->stats->reasm_fails++;
free ( fragment );
}
@ -89,6 +91,9 @@ struct io_buffer * fragment_reassemble ( struct fragment_reassembler *fragments,
size_t expected_offset;
int more_frags;
/* Update statistics */
fragments->stats->reasm_reqds++;
/* Find matching fragment reassembly buffer, if any */
fragment = fragment_find ( fragments, iobuf, *hdrlen );
@ -115,6 +120,7 @@ struct io_buffer * fragment_reassemble ( struct fragment_reassembler *fragments,
fragment->iobuf = iobuf;
fragment->hdrlen = *hdrlen;
timer_init ( &fragment->timer, fragment_expired, NULL );
fragment->fragments = fragments;
DBGC ( fragment, "FRAG %p [0,%zd)\n", fragment,
( iob_len ( iobuf ) - *hdrlen ) );
@ -157,6 +163,7 @@ struct io_buffer * fragment_reassemble ( struct fragment_reassembler *fragments,
*hdrlen = fragment->hdrlen;
list_del ( &fragment->list );
free ( fragment );
fragments->stats->reasm_oks++;
return iobuf;
}
}
@ -167,6 +174,7 @@ struct io_buffer * fragment_reassemble ( struct fragment_reassembler *fragments,
return NULL;
drop:
fragments->stats->reasm_fails++;
free_iob ( iobuf );
return NULL;
}

55
src/net/ipv4.c
View File

@ -15,6 +15,7 @@
#include <ipxe/dhcp.h>
#include <ipxe/settings.h>
#include <ipxe/fragment.h>
#include <ipxe/ipstat.h>
/** @file
*
@ -30,6 +31,16 @@ static uint8_t next_ident_high = 0;
/** List of IPv4 miniroutes */
struct list_head ipv4_miniroutes = LIST_HEAD_INIT ( ipv4_miniroutes );
/** IPv4 statistics */
static struct ip_statistics ipv4_stats;
/** IPv4 statistics family */
struct ip_statistics_family
ipv4_stats_family __ip_statistics_family ( IP_STATISTICS_IPV4 ) = {
.version = 4,
.stats = &ipv4_stats,
};
/**
* Add IPv4 minirouting table entry
*
@ -178,6 +189,7 @@ static struct fragment_reassembler ipv4_reassembler = {
.is_fragment = ipv4_is_fragment,
.fragment_offset = ipv4_fragment_offset,
.more_fragments = ipv4_more_fragments,
.stats = &ipv4_stats,
};
/**
@ -232,6 +244,9 @@ static int ipv4_tx ( struct io_buffer *iobuf,
const void *ll_dest;
int rc;
/* Update statistics */
ipv4_stats.out_requests++;
/* Fill up the IP header, except source address */
memset ( iphdr, 0, sizeof ( *iphdr ) );
iphdr->verhdrlen = ( IP_VER | ( sizeof ( *iphdr ) / 4 ) );
@ -255,6 +270,7 @@ static int ipv4_tx ( struct io_buffer *iobuf,
if ( ! netdev ) {
DBGC ( sin_dest->sin_addr, "IPv4 has no route to %s\n",
inet_ntoa ( iphdr->dest ) );
ipv4_stats.out_no_routes++;
rc = -ENETUNREACH;
goto err;
}
@ -282,9 +298,11 @@ static int ipv4_tx ( struct io_buffer *iobuf,
/* Calculate link-layer destination address, if possible */
if ( ( ( next_hop.s_addr ^ INADDR_BROADCAST ) & ~netmask.s_addr ) == 0){
/* Broadcast address */
ipv4_stats.out_bcast_pkts++;
ll_dest = netdev->ll_broadcast;
} else if ( IN_MULTICAST ( ntohl ( next_hop.s_addr ) ) ) {
/* Multicast address */
ipv4_stats.out_mcast_pkts++;
if ( ( rc = netdev->ll_protocol->mc_hash ( AF_INET, &next_hop,
ll_dest_buf ) ) !=0){
DBGC ( sin_dest->sin_addr, "IPv4 could not hash "
@ -298,6 +316,10 @@ static int ipv4_tx ( struct io_buffer *iobuf,
ll_dest = NULL;
}
/* Update statistics */
ipv4_stats.out_transmits++;
ipv4_stats.out_octets += iob_len ( iobuf );
/* Hand off to link layer (via ARP if applicable) */
if ( ll_dest ) {
if ( ( rc = net_tx ( iobuf, netdev, &ipv4_protocol, ll_dest,
@ -389,43 +411,53 @@ static int ipv4_rx ( struct io_buffer *iobuf,
uint16_t pshdr_csum;
int rc;
/* Update statistics */
ipv4_stats.in_receives++;
ipv4_stats.in_octets += iob_len ( iobuf );
if ( flags & LL_BROADCAST ) {
ipv4_stats.in_bcast_pkts++;
} else if ( flags & LL_MULTICAST ) {
ipv4_stats.in_mcast_pkts++;
}
/* Sanity check the IPv4 header */
if ( iob_len ( iobuf ) < sizeof ( *iphdr ) ) {
DBGC ( iphdr->src, "IPv4 packet too short at %zd bytes (min "
"%zd bytes)\n", iob_len ( iobuf ), sizeof ( *iphdr ) );
goto err;
goto err_header;
}
if ( ( iphdr->verhdrlen & IP_MASK_VER ) != IP_VER ) {
DBGC ( iphdr->src, "IPv4 version %#02x not supported\n",
iphdr->verhdrlen );
goto err;
goto err_header;
}
hdrlen = ( ( iphdr->verhdrlen & IP_MASK_HLEN ) * 4 );
if ( hdrlen < sizeof ( *iphdr ) ) {
DBGC ( iphdr->src, "IPv4 header too short at %zd bytes (min "
"%zd bytes)\n", hdrlen, sizeof ( *iphdr ) );
goto err;
goto err_header;
}
if ( hdrlen > iob_len ( iobuf ) ) {
DBGC ( iphdr->src, "IPv4 header too long at %zd bytes "
"(packet is %zd bytes)\n", hdrlen, iob_len ( iobuf ) );
goto err;
goto err_header;
}
if ( ( csum = tcpip_chksum ( iphdr, hdrlen ) ) != 0 ) {
DBGC ( iphdr->src, "IPv4 checksum incorrect (is %04x "
"including checksum field, should be 0000)\n", csum );
goto err;
goto err_header;
}
len = ntohs ( iphdr->len );
if ( len < hdrlen ) {
DBGC ( iphdr->src, "IPv4 length too short at %zd bytes "
"(header is %zd bytes)\n", len, hdrlen );
goto err;
goto err_header;
}
if ( len > iob_len ( iobuf ) ) {
DBGC ( iphdr->src, "IPv4 length too long at %zd bytes "
"(packet is %zd bytes)\n", len, iob_len ( iobuf ) );
goto err;
ipv4_stats.in_truncated_pkts++;
goto err_other;
}
/* Truncate packet to correct length */
@ -443,7 +475,8 @@ static int ipv4_rx ( struct io_buffer *iobuf,
( ! ipv4_has_addr ( netdev, iphdr->dest ) ) ) {
DBGC ( iphdr->src, "IPv4 discarding non-local unicast packet "
"for %s\n", inet_ntoa ( iphdr->dest ) );
goto err;
ipv4_stats.in_addr_errors++;
goto err_other;
}
/* Perform fragment reassembly if applicable */
@ -470,7 +503,7 @@ static int ipv4_rx ( struct io_buffer *iobuf,
pshdr_csum = ipv4_pshdr_chksum ( iobuf, TCPIP_EMPTY_CSUM );
iob_pull ( iobuf, hdrlen );
if ( ( rc = tcpip_rx ( iobuf, netdev, iphdr->protocol, &src.st,
&dest.st, pshdr_csum ) ) != 0 ) {
&dest.st, pshdr_csum, &ipv4_stats ) ) != 0 ) {
DBGC ( src.sin.sin_addr, "IPv4 received packet rejected by "
"stack: %s\n", strerror ( rc ) );
return rc;
@ -478,7 +511,9 @@ static int ipv4_rx ( struct io_buffer *iobuf,
return 0;
err:
err_header:
ipv4_stats.in_hdr_errors++;
err_other:
free_iob ( iobuf );
return -EINVAL;
}

52
src/net/ipv6.c
View File

@ -31,6 +31,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#include <ipxe/if_ether.h>
#include <ipxe/crc32.h>
#include <ipxe/fragment.h>
#include <ipxe/ipstat.h>
#include <ipxe/ndp.h>
#include <ipxe/ipv6.h>
@ -57,6 +58,16 @@ FILE_LICENCE ( GPL2_OR_LATER );
/** List of IPv6 miniroutes */
struct list_head ipv6_miniroutes = LIST_HEAD_INIT ( ipv6_miniroutes );
/** IPv6 statistics */
static struct ip_statistics ipv6_stats;
/** IPv6 statistics family */
struct ip_statistics_family
ipv6_statistics_family __ip_statistics_family ( IP_STATISTICS_IPV6 ) = {
.version = 6,
.stats = &ipv6_stats,
};
/**
* Determine debugging colour for IPv6 debug messages
*
@ -398,6 +409,7 @@ static struct fragment_reassembler ipv6_reassembler = {
.is_fragment = ipv6_is_fragment,
.fragment_offset = ipv6_fragment_offset,
.more_fragments = ipv6_more_fragments,
.stats = &ipv6_stats,
};
/**
@ -455,6 +467,9 @@ static int ipv6_tx ( struct io_buffer *iobuf,
size_t len;
int rc;
/* Update statistics */
ipv6_stats.out_requests++;
/* Fill up the IPv6 header, except source address */
len = iob_len ( iobuf );
iphdr = iob_push ( iobuf, sizeof ( *iphdr ) );
@ -475,6 +490,7 @@ static int ipv6_tx ( struct io_buffer *iobuf,
if ( ! netdev ) {
DBGC ( ipv6col ( &iphdr->dest ), "IPv6 has no route to %s\n",
inet6_ntoa ( &iphdr->dest ) );
ipv6_stats.out_no_routes++;
rc = -ENETUNREACH;
goto err;
}
@ -498,6 +514,7 @@ static int ipv6_tx ( struct io_buffer *iobuf,
/* Calculate link-layer destination address, if possible */
if ( IN6_IS_ADDR_MULTICAST ( next_hop ) ) {
/* Multicast address */
ipv6_stats.out_mcast_pkts++;
if ( ( rc = netdev->ll_protocol->mc_hash ( AF_INET6, next_hop,
ll_dest_buf ) ) !=0){
DBGC ( ipv6col ( &iphdr->dest ), "IPv6 could not hash "
@ -511,6 +528,10 @@ static int ipv6_tx ( struct io_buffer *iobuf,
ll_dest = NULL;
}
/* Update statistics */
ipv6_stats.out_transmits++;
ipv6_stats.out_octets += iob_len ( iobuf );
/* Hand off to link layer (via NDP if applicable) */
if ( ll_dest ) {
if ( ( rc = net_tx ( iobuf, netdev, &ipv6_protocol, ll_dest,
@ -568,20 +589,29 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
int next_header;
int rc;
/* Update statistics */
ipv6_stats.in_receives++;
ipv6_stats.in_octets += iob_len ( iobuf );
if ( flags & LL_BROADCAST ) {
ipv6_stats.in_bcast_pkts++;
} else if ( flags & LL_MULTICAST ) {
ipv6_stats.in_mcast_pkts++;
}
/* Sanity check the IPv6 header */
if ( iob_len ( iobuf ) < sizeof ( *iphdr ) ) {
DBGC ( ipv6col ( &iphdr->src ), "IPv6 packet too short at %zd "
"bytes (min %zd bytes)\n", iob_len ( iobuf ),
sizeof ( *iphdr ) );
rc = -EINVAL_LEN;
goto err;
goto err_header;
}
if ( ( iphdr->ver_tc_label & htonl ( IPV6_MASK_VER ) ) !=
htonl ( IPV6_VER ) ) {
DBGC ( ipv6col ( &iphdr->src ), "IPv6 version %#08x not "
"supported\n", ntohl ( iphdr->ver_tc_label ) );
rc = -ENOTSUP_VER;
goto err;
goto err_header;
}
/* Truncate packet to specified length */
@ -589,8 +619,9 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
if ( len > iob_len ( iobuf ) ) {
DBGC ( ipv6col ( &iphdr->src ), "IPv6 length too long at %zd "
"bytes (packet is %zd bytes)\n", len, iob_len ( iobuf ));
ipv6_stats.in_truncated_pkts++;
rc = -EINVAL_LEN;
goto err;
goto err_other;
}
iob_unput ( iobuf, ( iob_len ( iobuf ) - len - sizeof ( *iphdr ) ) );
hdrlen = sizeof ( *iphdr );
@ -606,8 +637,9 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
( ! ipv6_has_addr ( netdev, &iphdr->dest ) ) ) {
DBGC ( ipv6col ( &iphdr->src ), "IPv6 discarding non-local "
"unicast packet for %s\n", inet6_ntoa ( &iphdr->dest ) );
ipv6_stats.in_addr_errors++;
rc = -EPIPE;
goto err;
goto err_other;
}
/* Process any extension headers */
@ -624,7 +656,7 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
"%zd bytes)\n", this_header,
( iob_len ( iobuf ) - hdrlen ), extlen );
rc = -EINVAL_LEN;
goto err;
goto err_header;
}
/* Determine size of extension header (if applicable) */
@ -645,7 +677,7 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
"%zd bytes)\n", this_header,
( iob_len ( iobuf ) - hdrlen ), extlen );
rc = -EINVAL_LEN;
goto err;
goto err_header;
}
hdrlen += extlen;
next_header = ext->common.next_header;
@ -662,7 +694,7 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
/* Check that all options can be ignored */
if ( ( rc = ipv6_check_options ( iphdr, &ext->options,
extlen ) ) != 0 )
goto err;
goto err_header;
} else if ( this_header == IPV6_FRAGMENT ) {
@ -692,7 +724,7 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
pshdr_csum = ipv6_pshdr_chksum ( iphdr, iob_len ( iobuf ),
next_header, TCPIP_EMPTY_CSUM );
if ( ( rc = tcpip_rx ( iobuf, netdev, next_header, &src.st, &dest.st,
pshdr_csum ) ) != 0 ) {
pshdr_csum, &ipv6_stats ) ) != 0 ) {
DBGC ( ipv6col ( &src.sin6.sin6_addr ), "IPv6 received packet "
"rejected by stack: %s\n", strerror ( rc ) );
return rc;
@ -700,7 +732,9 @@ static int ipv6_rx ( struct io_buffer *iobuf, struct net_device *netdev,
return 0;
err:
err_header:
ipv6_stats.in_hdr_errors++;
err_other:
free_iob ( iobuf );
return rc;
}

8
src/net/tcpip.c
View File

@ -5,6 +5,7 @@
#include <byteswap.h>
#include <ipxe/iobuf.h>
#include <ipxe/tables.h>
#include <ipxe/ipstat.h>
#include <ipxe/tcpip.h>
/** @file
@ -25,6 +26,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
* @v st_src Partially-filled source address
* @v st_dest Partially-filled destination address
* @v pshdr_csum Pseudo-header checksum
* @v stats IP statistics
* @ret rc Return status code
*
* This function expects a transport-layer segment from the network
@ -35,20 +37,22 @@ FILE_LICENCE ( GPL2_OR_LATER );
*/
int tcpip_rx ( struct io_buffer *iobuf, struct net_device *netdev,
uint8_t tcpip_proto, struct sockaddr_tcpip *st_src,
struct sockaddr_tcpip *st_dest,
uint16_t pshdr_csum ) {
struct sockaddr_tcpip *st_dest, uint16_t pshdr_csum,
struct ip_statistics *stats ) {
struct tcpip_protocol *tcpip;
/* Hand off packet to the appropriate transport-layer protocol */
for_each_table_entry ( tcpip, TCPIP_PROTOCOLS ) {
if ( tcpip->tcpip_proto == tcpip_proto ) {
DBG ( "TCP/IP received %s packet\n", tcpip->name );
stats->in_delivers++;
return tcpip->rx ( iobuf, netdev, st_src, st_dest,
pshdr_csum );
}
}
DBG ( "Unrecognised TCP/IP protocol %d\n", tcpip_proto );
stats->in_unknown_protos++;
free_iob ( iobuf );
return -EPROTONOSUPPORT;
}