'\" te
.\" Copyright (C) 2008, Sun Microsystems, Inc. All Rights Reserved.
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
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.TH net_isvalidchecksum 9F "1 May 2008" "SunOS 5.11" "Kernel Functions for Drivers"
.SH NAME
net_isvalidchecksum \- verify layer 3 and layer 4  checksums
.SH SYNOPSIS
.LP
.nf
#include <sys/neti.h>

\fBint\fR \fBnet_isvalidchecksum\fR(\fBconst\fR \fBnet_data_t\fR \fInet\fR, \fBmblk_t\fR *\fImb\fR);
.fi

.SH INTERFACE LEVEL
.sp
.LP
Solaris DDI specific (Solaris DDI).
.SH PARAMETERS
.sp
.ne 2
.mk
.na
\fB\fInet\fR\fR
.ad
.RS 7n
.rt  
value returned from a successful call to \fBnet_protocol_lookup\fR(9F).
.RE

.sp
.ne 2
.mk
.na
\fB\fImb\fR\fR
.ad
.RS 6n
.rt  
the \fBmblk\fR structure holding a packet that is the subject of this query.
.RE

.SH DESCRIPTION
.sp
.LP
The \fBnet_isvalidchecksum()\fR function verifies the layer 3 checksum (and, in
some case, the layer 4 checksum) in the packet. If possible, fields that are
used by hardware checksum'ing are examined rather than  manually verifying that
the checksums are present for packets received from a network interface.
.sp
.LP
For both \fBIPv4\fR and \fBIPv6\fR, \fBTCP\fR, \fBUDP\fR and \fBICMP\fR
(including \fBICMPV6\fR for \fBIPv6\fR) layer 4 checksums are currently
validated.
.SH RETURN VALUES
.sp
.LP
The \fBnet_isvalidchecksum()\fR function returns:
.sp
.ne 2
.mk
.na
\fB-1\fR
.ad
.RS 6n
.rt  
The network protocol does not support this function.
.RE

.sp
.ne 2
.mk
.na
\fB0\fR
.ad
.RS 6n
.rt  
The packet does not contain partial checksums.
.RE

.sp
.ne 2
.mk
.na
\fB1\fR
.ad
.RS 6n
.rt  
The packet does contain partial checksums.
.RE

.SH CONTEXT
.sp
.LP
The \fBnet_isvalidchecksum()\fR function may be called from user,  kernel, or
interrupt context.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityCommitted
.TE

.SH SEE ALSO
.sp
.LP
\fBnet_ispartialchecksum\fR(9F), \fBnet_protocol_lookup\fR(9F),
\fBattributes\fR(5)