incubator-nuttx/net/utils/net_ipchksum.c

312 lines
9.7 KiB
C

/****************************************************************************
* net/utils/net_ipchksum.c
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <nuttx/net/netdev.h>
#include <nuttx/net/ip.h>
#include "utils/utils.h"
#ifdef CONFIG_NET
/****************************************************************************
* Public Functions
****************************************************************************/
#if !defined(CONFIG_NET_ARCH_CHKSUM) && \
defined(CONFIG_NET_IPv4) && defined(CONFIG_MM_IOB)
/****************************************************************************
* Name: ipv4_upperlayer_header_chksum
*
* Description:
* Perform the checksum calculation over the IPv4, protocol headers,
* IP source and destination addresses
*
* Input Parameters:
* dev - The network driver instance. The packet data is in the d_buf
* of the device.
* proto - The protocol being supported
*
* Returned Value:
* The calculated checksum with pseudo-header and IP source and
* destination addresses
*
****************************************************************************/
uint16_t ipv4_upperlayer_header_chksum(FAR struct net_driver_s *dev,
uint8_t proto)
{
FAR struct ipv4_hdr_s *ipv4 = IPv4BUF;
uint16_t upperlen;
uint16_t iphdrlen;
uint16_t sum;
/* Get the IP header length (accounting for possible options). */
iphdrlen = (ipv4->vhl & IPv4_HLMASK) << 2;
/* The length reported in the IPv4 header is the length of both the IPv4
* header and the payload that follows the header. We need to subtract
* the size of the IPv4 header to get the size of the payload.
*/
upperlen = (((uint16_t)(ipv4->len[0]) << 8) + ipv4->len[1]) - iphdrlen;
/* First sum pseudo-header.
*
* IP protocol and length fields. This addition cannot carry.
*/
sum = upperlen + proto;
/* Sum IP source and destination addresses. */
return chksum(sum, (FAR uint8_t *)&ipv4->srcipaddr, 2 * sizeof(in_addr_t));
}
/****************************************************************************
* Name: ipv4_upperlayer_payload_chksum
*
* Description:
* Perform the checksum calculation over the iob data payload
*
* Input Parameters:
* dev - The network driver instance. The packet data is in the d_buf
* of the device.
* sum - The default checksum
*
* Returned Value:
* The calculated checksum with iob data payload and default checksum
*
****************************************************************************/
uint16_t ipv4_upperlayer_payload_chksum(FAR struct net_driver_s *dev,
uint16_t sum)
{
FAR struct ipv4_hdr_s *ipv4 = IPv4BUF;
uint16_t iphdrlen;
/* Get the IP header length (accounting for possible options). */
iphdrlen = (ipv4->vhl & IPv4_HLMASK) << 2;
/* Sum IP payload data. */
return chksum_iob(sum, dev->d_iob, iphdrlen);
}
/****************************************************************************
* Name: ipv4_upperlayer_chksum
*
* Description:
* Perform the checksum calculation over the IPv4, protocol headers, and
* data payload as necessary.
*
* Input Parameters:
* dev - The network driver instance. The packet data is in the d_buf
* of the device.
* proto - The protocol being supported
*
* Returned Value:
* The calculated checksum
*
****************************************************************************/
uint16_t ipv4_upperlayer_chksum(FAR struct net_driver_s *dev, uint8_t proto)
{
uint16_t sum;
/* Sum pseudo-header IP source and destination addresses. */
sum = ipv4_upperlayer_header_chksum(dev, proto);
/* Sum IP payload data. */
sum = ipv4_upperlayer_payload_chksum(dev, sum);
return (sum == 0) ? 0xffff : HTONS(sum);
}
#endif /* CONFIG_NET_ARCH_CHKSUM */
#if !defined(CONFIG_NET_ARCH_CHKSUM) && \
defined(CONFIG_NET_IPv6) && defined(CONFIG_MM_IOB)
/****************************************************************************
* Name: ipv6_upperlayer_header_chksum
*
* Description:
* Perform the checksum calculation over the IPv6, protocol headers,
* IP source and destination addresses.
*
* Input Parameters:
* dev - The network driver instance. The packet data is in the d_buf
* of the device.
* proto - The protocol being supported
* iplen - The size of the IPv6 header. This may be larger than
* IPv6_HDRLEN the IPv6 header if IPv6 extension headers are
* present.
*
* Returned Value:
* The calculated checksum
*
****************************************************************************/
uint16_t ipv6_upperlayer_header_chksum(FAR struct net_driver_s *dev,
uint8_t proto, unsigned int iplen)
{
FAR struct ipv6_hdr_s *ipv6 = IPv6BUF;
uint16_t upperlen;
uint16_t sum;
DEBUGASSERT(dev != NULL && iplen >= IPv6_HDRLEN);
/* The length reported in the IPv6 header is the length of the payload
* that follows the header. If extension heders are present, then this
* size includes the size of the IPv6 extension headers.
*/
upperlen = ((uint16_t)ipv6->len[0] << 8) + ipv6->len[1];
/* Adjust for the presence of any extension headers */
upperlen -= (iplen - IPv6_HDRLEN);
/* The checksum is calculated starting with a pseudo-header of IPv6 header
* fields according to the IPv6 standard, which consists of the source
* and destination addresses, the packet length and the next header field.
*/
sum = upperlen + proto;
/* Sum IP source and destination addresses. */
return chksum(sum, (FAR uint8_t *)&ipv6->srcipaddr,
2 * sizeof(net_ipv6addr_t));
}
/****************************************************************************
* Name: ipv6_upperlayer_payload_chksum
*
* Description:
* Perform the checksum calculation over the IPv6, protocol headers,
* IP source and destination addresses.
*
* Input Parameters:
* dev - The network driver instance. The packet data is in the d_buf
* of the device.
* proto - The protocol being supported
* iplen - The size of the IPv6 header. This may be larger than
* IPv6_HDRLEN the IPv6 header if IPv6 extension headers are
* present.
*
* Returned Value:
* The calculated checksum
*
****************************************************************************/
uint16_t ipv6_upperlayer_payload_chksum(FAR struct net_driver_s *dev,
unsigned int iplen, uint16_t sum)
{
/* Sum IP payload data. */
return chksum_iob(sum, dev->d_iob, iplen);
}
/****************************************************************************
* Name: ipv6_upperlayer_chksum
*
* Description:
* Perform the checksum calculation over the IPv6, protocol headers, and
* data payload as necessary.
*
* Input Parameters:
* dev - The network driver instance. The packet data is in the d_buf
* of the device.
* proto - The protocol being supported
* iplen - The size of the IPv6 header. This may be larger than
* IPv6_HDRLEN the IPv6 header if IPv6 extension headers are
* present.
*
* Returned Value:
* The calculated checksum
*
****************************************************************************/
uint16_t ipv6_upperlayer_chksum(FAR struct net_driver_s *dev,
uint8_t proto, unsigned int iplen)
{
uint16_t sum;
/* Sum IP source and destination addresses. */
sum = ipv6_upperlayer_header_chksum(dev, proto, iplen);
/* Sum IP payload data. */
sum = ipv6_upperlayer_payload_chksum(dev, iplen, sum);
return (sum == 0) ? 0xffff : HTONS(sum);
}
#endif /* CONFIG_NET_ARCH_CHKSUM */
/****************************************************************************
* Name: ipv4_chksum
*
* Description:
* Calculate the IPv4 header checksum of the packet header in d_buf.
*
* The IPv4 header checksum is the Internet checksum of the 20 bytes of
* the IPv4 header.
*
* If CONFIG_NET_ARCH_CHKSUM is defined, then this function must be
* provided by architecture-specific logic.
*
* Returned Value:
* The IPv4 header checksum of the IPv4 header in the d_buf buffer.
*
****************************************************************************/
#if defined(CONFIG_NET_IPv4) && !defined(CONFIG_NET_ARCH_CHKSUM)
uint16_t ipv4_chksum(FAR struct ipv4_hdr_s *ipv4)
{
uint16_t iphdrlen;
uint16_t sum;
/* Get the IP header length (accounting for possible options). */
iphdrlen = (ipv4->vhl & IPv4_HLMASK) << 2;
sum = chksum(0, (FAR const uint8_t *)ipv4, iphdrlen);
return (sum == 0) ? 0xffff : HTONS(sum);
}
#endif /* CONFIG_NET_ARCH_CHKSUM */
#endif /* CONFIG_NET */