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Diffstat (limited to 'drivers/net/sk98lin/skcsum.c')
| -rw-r--r-- | drivers/net/sk98lin/skcsum.c | 871 |
1 files changed, 871 insertions, 0 deletions
diff --git a/drivers/net/sk98lin/skcsum.c b/drivers/net/sk98lin/skcsum.c new file mode 100644 index 00000000000..38a6e7a631f --- /dev/null +++ b/drivers/net/sk98lin/skcsum.c @@ -0,0 +1,871 @@ +/****************************************************************************** + * + * Name: skcsum.c + * Project: GEnesis, PCI Gigabit Ethernet Adapter + * Version: $Revision: 1.12 $ + * Date: $Date: 2003/08/20 13:55:53 $ + * Purpose: Store/verify Internet checksum in send/receive packets. + * + ******************************************************************************/ + +/****************************************************************************** + * + * (C)Copyright 1998-2003 SysKonnect GmbH. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * The information in this file is provided "AS IS" without warranty. + * + ******************************************************************************/ + +#ifdef SK_USE_CSUM /* Check if CSUM is to be used. */ + +#ifndef lint +static const char SysKonnectFileId[] = + "@(#) $Id: skcsum.c,v 1.12 2003/08/20 13:55:53 mschmid Exp $ (C) SysKonnect."; +#endif /* !lint */ + +/****************************************************************************** + * + * Description: + * + * This is the "GEnesis" common module "CSUM". + * + * This module contains the code necessary to calculate, store, and verify the + * Internet Checksum of IP, TCP, and UDP frames. + * + * "GEnesis" is an abbreviation of "Gigabit Ethernet Network System in Silicon" + * and is the code name of this SysKonnect project. + * + * Compilation Options: + * + * SK_USE_CSUM - Define if CSUM is to be used. Otherwise, CSUM will be an + * empty module. + * + * SKCS_OVERWRITE_PROTO - Define to overwrite the default protocol id + * definitions. In this case, all SKCS_PROTO_xxx definitions must be made + * external. + * + * SKCS_OVERWRITE_STATUS - Define to overwrite the default return status + * definitions. In this case, all SKCS_STATUS_xxx definitions must be made + * external. + * + * Include File Hierarchy: + * + * "h/skdrv1st.h" + * "h/skcsum.h" + * "h/sktypes.h" + * "h/skqueue.h" + * "h/skdrv2nd.h" + * + ******************************************************************************/ + +#include "h/skdrv1st.h" +#include "h/skcsum.h" +#include "h/skdrv2nd.h" + +/* defines ********************************************************************/ + +/* The size of an Ethernet MAC header. */ +#define SKCS_ETHERNET_MAC_HEADER_SIZE (6+6+2) + +/* The size of the used topology's MAC header. */ +#define SKCS_MAC_HEADER_SIZE SKCS_ETHERNET_MAC_HEADER_SIZE + +/* The size of the IP header without any option fields. */ +#define SKCS_IP_HEADER_SIZE 20 + +/* + * Field offsets within the IP header. + */ + +/* "Internet Header Version" and "Length". */ +#define SKCS_OFS_IP_HEADER_VERSION_AND_LENGTH 0 + +/* "Total Length". */ +#define SKCS_OFS_IP_TOTAL_LENGTH 2 + +/* "Flags" "Fragment Offset". */ +#define SKCS_OFS_IP_FLAGS_AND_FRAGMENT_OFFSET 6 + +/* "Next Level Protocol" identifier. */ +#define SKCS_OFS_IP_NEXT_LEVEL_PROTOCOL 9 + +/* Source IP address. */ +#define SKCS_OFS_IP_SOURCE_ADDRESS 12 + +/* Destination IP address. */ +#define SKCS_OFS_IP_DESTINATION_ADDRESS 16 + + +/* + * Field offsets within the UDP header. + */ + +/* UDP checksum. */ +#define SKCS_OFS_UDP_CHECKSUM 6 + +/* IP "Next Level Protocol" identifiers (see RFC 790). */ +#define SKCS_PROTO_ID_TCP 6 /* Transport Control Protocol */ +#define SKCS_PROTO_ID_UDP 17 /* User Datagram Protocol */ + +/* IP "Don't Fragment" bit. */ +#define SKCS_IP_DONT_FRAGMENT SKCS_HTON16(0x4000) + +/* Add a byte offset to a pointer. */ +#define SKCS_IDX(pPtr, Ofs) ((void *) ((char *) (pPtr) + (Ofs))) + +/* + * Macros that convert host to network representation and vice versa, i.e. + * little/big endian conversion on little endian machines only. + */ +#ifdef SK_LITTLE_ENDIAN +#define SKCS_HTON16(Val16) (((unsigned) (Val16) >> 8) | (((Val16) & 0xff) << 8)) +#endif /* SK_LITTLE_ENDIAN */ +#ifdef SK_BIG_ENDIAN +#define SKCS_HTON16(Val16) (Val16) +#endif /* SK_BIG_ENDIAN */ +#define SKCS_NTOH16(Val16) SKCS_HTON16(Val16) + +/* typedefs *******************************************************************/ + +/* function prototypes ********************************************************/ + +/****************************************************************************** + * + * SkCsGetSendInfo - get checksum information for a send packet + * + * Description: + * Get all checksum information necessary to send a TCP or UDP packet. The + * function checks the IP header passed to it. If the high-level protocol + * is either TCP or UDP the pseudo header checksum is calculated and + * returned. + * + * The function returns the total length of the IP header (including any + * IP option fields), which is the same as the start offset of the IP data + * which in turn is the start offset of the TCP or UDP header. + * + * The function also returns the TCP or UDP pseudo header checksum, which + * should be used as the start value for the hardware checksum calculation. + * (Note that any actual pseudo header checksum can never calculate to + * zero.) + * + * Note: + * There is a bug in the GENESIS ASIC which may lead to wrong checksums. + * + * Arguments: + * pAc - A pointer to the adapter context struct. + * + * pIpHeader - Pointer to IP header. Must be at least the IP header *not* + * including any option fields, i.e. at least 20 bytes. + * + * Note: This pointer will be used to address 8-, 16-, and 32-bit + * variables with the respective alignment offsets relative to the pointer. + * Thus, the pointer should point to a 32-bit aligned address. If the + * target system cannot address 32-bit variables on non 32-bit aligned + * addresses, then the pointer *must* point to a 32-bit aligned address. + * + * pPacketInfo - A pointer to the packet information structure for this + * packet. Before calling this SkCsGetSendInfo(), the following field must + * be initialized: + * + * ProtocolFlags - Initialize with any combination of + * SKCS_PROTO_XXX bit flags. SkCsGetSendInfo() will only work on + * the protocols specified here. Any protocol(s) not specified + * here will be ignored. + * + * Note: Only one checksum can be calculated in hardware. Thus, if + * SKCS_PROTO_IP is specified in the 'ProtocolFlags', + * SkCsGetSendInfo() must calculate the IP header checksum in + * software. It might be a better idea to have the calling + * protocol stack calculate the IP header checksum. + * + * Returns: N/A + * On return, the following fields in 'pPacketInfo' may or may not have + * been filled with information, depending on the protocol(s) found in the + * packet: + * + * ProtocolFlags - Returns the SKCS_PROTO_XXX bit flags of the protocol(s) + * that were both requested by the caller and actually found in the packet. + * Protocol(s) not specified by the caller and/or not found in the packet + * will have their respective SKCS_PROTO_XXX bit flags reset. + * + * Note: For IP fragments, TCP and UDP packet information is ignored. + * + * IpHeaderLength - The total length in bytes of the complete IP header + * including any option fields is returned here. This is the start offset + * of the IP data, i.e. the TCP or UDP header if present. + * + * IpHeaderChecksum - If IP has been specified in the 'ProtocolFlags', the + * 16-bit Internet Checksum of the IP header is returned here. This value + * is to be stored into the packet's 'IP Header Checksum' field. + * + * PseudoHeaderChecksum - If this is a TCP or UDP packet and if TCP or UDP + * has been specified in the 'ProtocolFlags', the 16-bit Internet Checksum + * of the TCP or UDP pseudo header is returned here. + */ +void SkCsGetSendInfo( +SK_AC *pAc, /* Adapter context struct. */ +void *pIpHeader, /* IP header. */ +SKCS_PACKET_INFO *pPacketInfo, /* Packet information struct. */ +int NetNumber) /* Net number */ +{ + /* Internet Header Version found in IP header. */ + unsigned InternetHeaderVersion; + + /* Length of the IP header as found in IP header. */ + unsigned IpHeaderLength; + + /* Bit field specifiying the desired/found protocols. */ + unsigned ProtocolFlags; + + /* Next level protocol identifier found in IP header. */ + unsigned NextLevelProtocol; + + /* Length of IP data portion. */ + unsigned IpDataLength; + + /* TCP/UDP pseudo header checksum. */ + unsigned long PseudoHeaderChecksum; + + /* Pointer to next level protocol statistics structure. */ + SKCS_PROTO_STATS *NextLevelProtoStats; + + /* Temporary variable. */ + unsigned Tmp; + + Tmp = *(SK_U8 *) + SKCS_IDX(pIpHeader, SKCS_OFS_IP_HEADER_VERSION_AND_LENGTH); + + /* Get the Internet Header Version (IHV). */ + /* Note: The IHV is stored in the upper four bits. */ + + InternetHeaderVersion = Tmp >> 4; + + /* Check the Internet Header Version. */ + /* Note: We currently only support IP version 4. */ + + if (InternetHeaderVersion != 4) { /* IPv4? */ + SK_DBG_MSG(pAc, SK_DBGMOD_CSUM, SK_DBGCAT_ERR | SK_DBGCAT_TX, + ("Tx: Unknown Internet Header Version %u.\n", + InternetHeaderVersion)); + pPacketInfo->ProtocolFlags = 0; + pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_IP].TxUnableCts++; + return; + } + + /* Get the IP header length (IHL). */ + /* + * Note: The IHL is stored in the lower four bits as the number of + * 4-byte words. + */ + + IpHeaderLength = (Tmp & 0xf) * 4; + pPacketInfo->IpHeaderLength = IpHeaderLength; + + /* Check the IP header length. */ + + /* 04-Aug-1998 sw - Really check the IHL? Necessary? */ + + if (IpHeaderLength < 5*4) { + SK_DBG_MSG(pAc, SK_DBGMOD_CSUM, SK_DBGCAT_ERR | SK_DBGCAT_TX, + ("Tx: Invalid IP Header Length %u.\n", IpHeaderLength)); + pPacketInfo->ProtocolFlags = 0; + pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_IP].TxUnableCts++; + return; + } + + /* This is an IPv4 frame with a header of valid length. */ + + pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_IP].TxOkCts++; + + /* Check if we should calculate the IP header checksum. */ + + ProtocolFlags = pPacketInfo->ProtocolFlags; + + if (ProtocolFlags & SKCS_PROTO_IP) { + pPacketInfo->IpHeaderChecksum = + SkCsCalculateChecksum(pIpHeader, IpHeaderLength); + } + + /* Get the next level protocol identifier. */ + + NextLevelProtocol = + *(SK_U8 *) SKCS_IDX(pIpHeader, SKCS_OFS_IP_NEXT_LEVEL_PROTOCOL); + + /* + * Check if this is a TCP or UDP frame and if we should calculate the + * TCP/UDP pseudo header checksum. + * + * Also clear all protocol bit flags of protocols not present in the + * frame. + */ + + if ((ProtocolFlags & SKCS_PROTO_TCP) != 0 && + NextLevelProtocol == SKCS_PROTO_ID_TCP) { + /* TCP/IP frame. */ + ProtocolFlags &= SKCS_PROTO_TCP | SKCS_PROTO_IP; + NextLevelProtoStats = + &pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_TCP]; + } + else if ((ProtocolFlags & SKCS_PROTO_UDP) != 0 && + NextLevelProtocol == SKCS_PROTO_ID_UDP) { + /* UDP/IP frame. */ + ProtocolFlags &= SKCS_PROTO_UDP | SKCS_PROTO_IP; + NextLevelProtoStats = + &pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_UDP]; + } + else { + /* + * Either not a TCP or UDP frame and/or TCP/UDP processing not + * specified. + */ + pPacketInfo->ProtocolFlags = ProtocolFlags & SKCS_PROTO_IP; + return; + } + + /* Check if this is an IP fragment. */ + + /* + * Note: An IP fragment has a non-zero "Fragment Offset" field and/or + * the "More Fragments" bit set. Thus, if both the "Fragment Offset" + * and the "More Fragments" are zero, it is *not* a fragment. We can + * easily check both at the same time since they are in the same 16-bit + * word. + */ + + if ((*(SK_U16 *) + SKCS_IDX(pIpHeader, SKCS_OFS_IP_FLAGS_AND_FRAGMENT_OFFSET) & + ~SKCS_IP_DONT_FRAGMENT) != 0) { + /* IP fragment; ignore all other protocols. */ + pPacketInfo->ProtocolFlags = ProtocolFlags & SKCS_PROTO_IP; + NextLevelProtoStats->TxUnableCts++; + return; + } + + /* + * Calculate the TCP/UDP pseudo header checksum. + */ + + /* Get total length of IP header and data. */ + + IpDataLength = + *(SK_U16 *) SKCS_IDX(pIpHeader, SKCS_OFS_IP_TOTAL_LENGTH); + + /* Get length of IP data portion. */ + + IpDataLength = SKCS_NTOH16(IpDataLength) - IpHeaderLength; + + /* Calculate the sum of all pseudo header fields (16-bit). */ + + PseudoHeaderChecksum = + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_SOURCE_ADDRESS + 0) + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_SOURCE_ADDRESS + 2) + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_DESTINATION_ADDRESS + 0) + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_DESTINATION_ADDRESS + 2) + + (unsigned long) SKCS_HTON16(NextLevelProtocol) + + (unsigned long) SKCS_HTON16(IpDataLength); + + /* Add-in any carries. */ + + SKCS_OC_ADD(PseudoHeaderChecksum, PseudoHeaderChecksum, 0); + + /* Add-in any new carry. */ + + SKCS_OC_ADD(pPacketInfo->PseudoHeaderChecksum, PseudoHeaderChecksum, 0); + + pPacketInfo->ProtocolFlags = ProtocolFlags; + NextLevelProtoStats->TxOkCts++; /* Success. */ +} /* SkCsGetSendInfo */ + + +/****************************************************************************** + * + * SkCsGetReceiveInfo - verify checksum information for a received packet + * + * Description: + * Verify a received frame's checksum. The function returns a status code + * reflecting the result of the verification. + * + * Note: + * Before calling this function you have to verify that the frame is + * not padded and Checksum1 and Checksum2 are bigger than 1. + * + * Arguments: + * pAc - Pointer to adapter context struct. + * + * pIpHeader - Pointer to IP header. Must be at least the length in bytes + * of the received IP header including any option fields. For UDP packets, + * 8 additional bytes are needed to access the UDP checksum. + * + * Note: The actual length of the IP header is stored in the lower four + * bits of the first octet of the IP header as the number of 4-byte words, + * so it must be multiplied by four to get the length in bytes. Thus, the + * maximum IP header length is 15 * 4 = 60 bytes. + * + * Checksum1 - The first 16-bit Internet Checksum calculated by the + * hardware starting at the offset returned by SkCsSetReceiveFlags(). + * + * Checksum2 - The second 16-bit Internet Checksum calculated by the + * hardware starting at the offset returned by SkCsSetReceiveFlags(). + * + * Returns: + * SKCS_STATUS_UNKNOWN_IP_VERSION - Not an IP v4 frame. + * SKCS_STATUS_IP_CSUM_ERROR - IP checksum error. + * SKCS_STATUS_IP_CSUM_ERROR_TCP - IP checksum error in TCP frame. + * SKCS_STATUS_IP_CSUM_ERROR_UDP - IP checksum error in UDP frame + * SKCS_STATUS_IP_FRAGMENT - IP fragment (IP checksum ok). + * SKCS_STATUS_IP_CSUM_OK - IP checksum ok (not a TCP or UDP frame). + * SKCS_STATUS_TCP_CSUM_ERROR - TCP checksum error (IP checksum ok). + * SKCS_STATUS_UDP_CSUM_ERROR - UDP checksum error (IP checksum ok). + * SKCS_STATUS_TCP_CSUM_OK - IP and TCP checksum ok. + * SKCS_STATUS_UDP_CSUM_OK - IP and UDP checksum ok. + * SKCS_STATUS_IP_CSUM_OK_NO_UDP - IP checksum OK and no UDP checksum. + * + * Note: If SKCS_OVERWRITE_STATUS is defined, the SKCS_STATUS_XXX values + * returned here can be defined in some header file by the module using CSUM. + * In this way, the calling module can assign return values for its own needs, + * e.g. by assigning bit flags to the individual protocols. + */ +SKCS_STATUS SkCsGetReceiveInfo( +SK_AC *pAc, /* Adapter context struct. */ +void *pIpHeader, /* IP header. */ +unsigned Checksum1, /* Hardware checksum 1. */ +unsigned Checksum2, /* Hardware checksum 2. */ +int NetNumber) /* Net number */ +{ + /* Internet Header Version found in IP header. */ + unsigned InternetHeaderVersion; + + /* Length of the IP header as found in IP header. */ + unsigned IpHeaderLength; + + /* Length of IP data portion. */ + unsigned IpDataLength; + + /* IP header checksum. */ + unsigned IpHeaderChecksum; + + /* IP header options checksum, if any. */ + unsigned IpOptionsChecksum; + + /* IP data checksum, i.e. TCP/UDP checksum. */ + unsigned IpDataChecksum; + + /* Next level protocol identifier found in IP header. */ + unsigned NextLevelProtocol; + + /* The checksum of the "next level protocol", i.e. TCP or UDP. */ + unsigned long NextLevelProtocolChecksum; + + /* Pointer to next level protocol statistics structure. */ + SKCS_PROTO_STATS *NextLevelProtoStats; + + /* Temporary variable. */ + unsigned Tmp; + + Tmp = *(SK_U8 *) + SKCS_IDX(pIpHeader, SKCS_OFS_IP_HEADER_VERSION_AND_LENGTH); + + /* Get the Internet Header Version (IHV). */ + /* Note: The IHV is stored in the upper four bits. */ + + InternetHeaderVersion = Tmp >> 4; + + /* Check the Internet Header Version. */ + /* Note: We currently only support IP version 4. */ + + if (InternetHeaderVersion != 4) { /* IPv4? */ + SK_DBG_MSG(pAc, SK_DBGMOD_CSUM, SK_DBGCAT_ERR | SK_DBGCAT_RX, + ("Rx: Unknown Internet Header Version %u.\n", + InternetHeaderVersion)); + pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_IP].RxUnableCts++; + return (SKCS_STATUS_UNKNOWN_IP_VERSION); + } + + /* Get the IP header length (IHL). */ + /* + * Note: The IHL is stored in the lower four bits as the number of + * 4-byte words. + */ + + IpHeaderLength = (Tmp & 0xf) * 4; + + /* Check the IP header length. */ + + /* 04-Aug-1998 sw - Really check the IHL? Necessary? */ + + if (IpHeaderLength < 5*4) { + SK_DBG_MSG(pAc, SK_DBGMOD_CSUM, SK_DBGCAT_ERR | SK_DBGCAT_RX, + ("Rx: Invalid IP Header Length %u.\n", IpHeaderLength)); + pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_IP].RxErrCts++; + return (SKCS_STATUS_IP_CSUM_ERROR); + } + + /* This is an IPv4 frame with a header of valid length. */ + + /* Get the IP header and data checksum. */ + + IpDataChecksum = Checksum2; + + /* + * The IP header checksum is calculated as follows: + * + * IpHeaderChecksum = Checksum1 - Checksum2 + */ + + SKCS_OC_SUB(IpHeaderChecksum, Checksum1, Checksum2); + + /* Check if any IP header options. */ + + if (IpHeaderLength > SKCS_IP_HEADER_SIZE) { + + /* Get the IP options checksum. */ + + IpOptionsChecksum = SkCsCalculateChecksum( + SKCS_IDX(pIpHeader, SKCS_IP_HEADER_SIZE), + IpHeaderLength - SKCS_IP_HEADER_SIZE); + + /* Adjust the IP header and IP data checksums. */ + + SKCS_OC_ADD(IpHeaderChecksum, IpHeaderChecksum, IpOptionsChecksum); + + SKCS_OC_SUB(IpDataChecksum, IpDataChecksum, IpOptionsChecksum); + } + + /* + * Check if the IP header checksum is ok. + * + * NOTE: We must check the IP header checksum even if the caller just wants + * us to check upper-layer checksums, because we cannot do any further + * processing of the packet without a valid IP checksum. + */ + + /* Get the next level protocol identifier. */ + + NextLevelProtocol = *(SK_U8 *) + SKCS_IDX(pIpHeader, SKCS_OFS_IP_NEXT_LEVEL_PROTOCOL); + + if (IpHeaderChecksum != 0xffff) { + pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_IP].RxErrCts++; + /* the NDIS tester wants to know the upper level protocol too */ + if (NextLevelProtocol == SKCS_PROTO_ID_TCP) { + return(SKCS_STATUS_IP_CSUM_ERROR_TCP); + } + else if (NextLevelProtocol == SKCS_PROTO_ID_UDP) { + return(SKCS_STATUS_IP_CSUM_ERROR_UDP); + } + return (SKCS_STATUS_IP_CSUM_ERROR); + } + + /* + * Check if this is a TCP or UDP frame and if we should calculate the + * TCP/UDP pseudo header checksum. + * + * Also clear all protocol bit flags of protocols not present in the + * frame. + */ + + if ((pAc->Csum.ReceiveFlags[NetNumber] & SKCS_PROTO_TCP) != 0 && + NextLevelProtocol == SKCS_PROTO_ID_TCP) { + /* TCP/IP frame. */ + NextLevelProtoStats = + &pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_TCP]; + } + else if ((pAc->Csum.ReceiveFlags[NetNumber] & SKCS_PROTO_UDP) != 0 && + NextLevelProtocol == SKCS_PROTO_ID_UDP) { + /* UDP/IP frame. */ + NextLevelProtoStats = + &pAc->Csum.ProtoStats[NetNumber][SKCS_PROTO_STATS_UDP]; + } + else { + /* + * Either not a TCP or UDP frame and/or TCP/UDP processing not + * specified. + */ + return (SKCS_STATUS_IP_CSUM_OK); + } + + /* Check if this is an IP fragment. */ + + /* + * Note: An IP fragment has a non-zero "Fragment Offset" field and/or + * the "More Fragments" bit set. Thus, if both the "Fragment Offset" + * and the "More Fragments" are zero, it is *not* a fragment. We can + * easily check both at the same time since they are in the same 16-bit + * word. + */ + + if ((*(SK_U16 *) + SKCS_IDX(pIpHeader, SKCS_OFS_IP_FLAGS_AND_FRAGMENT_OFFSET) & + ~SKCS_IP_DONT_FRAGMENT) != 0) { + /* IP fragment; ignore all other protocols. */ + NextLevelProtoStats->RxUnableCts++; + return (SKCS_STATUS_IP_FRAGMENT); + } + + /* + * 08-May-2000 ra + * + * From RFC 768 (UDP) + * If the computed checksum is zero, it is transmitted as all ones (the + * equivalent in one's complement arithmetic). An all zero transmitted + * checksum value means that the transmitter generated no checksum (for + * debugging or for higher level protocols that don't care). + */ + + if (NextLevelProtocol == SKCS_PROTO_ID_UDP && + *(SK_U16*)SKCS_IDX(pIpHeader, IpHeaderLength + 6) == 0x0000) { + + NextLevelProtoStats->RxOkCts++; + + return (SKCS_STATUS_IP_CSUM_OK_NO_UDP); + } + + /* + * Calculate the TCP/UDP checksum. + */ + + /* Get total length of IP header and data. */ + + IpDataLength = + *(SK_U16 *) SKCS_IDX(pIpHeader, SKCS_OFS_IP_TOTAL_LENGTH); + + /* Get length of IP data portion. */ + + IpDataLength = SKCS_NTOH16(IpDataLength) - IpHeaderLength; + + NextLevelProtocolChecksum = + + /* Calculate the pseudo header checksum. */ + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_SOURCE_ADDRESS + 0) + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_SOURCE_ADDRESS + 2) + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_DESTINATION_ADDRESS + 0) + + (unsigned long) *(SK_U16 *) SKCS_IDX(pIpHeader, + SKCS_OFS_IP_DESTINATION_ADDRESS + 2) + + (unsigned long) SKCS_HTON16(NextLevelProtocol) + + (unsigned long) SKCS_HTON16(IpDataLength) + + + /* Add the TCP/UDP header checksum. */ + + (unsigned long) IpDataChecksum; + + /* Add-in any carries. */ + + SKCS_OC_ADD(NextLevelProtocolChecksum, NextLevelProtocolChecksum, 0); + + /* Add-in any new carry. */ + + SKCS_OC_ADD(NextLevelProtocolChecksum, NextLevelProtocolChecksum, 0); + + /* Check if the TCP/UDP checksum is ok. */ + + if ((unsigned) NextLevelProtocolChecksum == 0xffff) { + + /* TCP/UDP checksum ok. */ + + NextLevelProtoStats->RxOkCts++; + + return (NextLevelProtocol == SKCS_PROTO_ID_TCP ? + SKCS_STATUS_TCP_CSUM_OK : SKCS_STATUS_UDP_CSUM_OK); + } + + /* TCP/UDP checksum error. */ + + NextLevelProtoStats->RxErrCts++; + + return (NextLevelProtocol == SKCS_PROTO_ID_TCP ? + SKCS_STATUS_TCP_CSUM_ERROR : SKCS_STATUS_UDP_CSUM_ERROR); +} /* SkCsGetReceiveInfo */ + + +/****************************************************************************** + * + * SkCsSetReceiveFlags - set checksum receive flags + * + * Description: + * Use this function to set the various receive flags. According to the + * protocol flags set by the caller, the start offsets within received + * packets of the two hardware checksums are returned. These offsets must + * be stored in all receive descriptors. + * + * Arguments: + * pAc - Pointer to adapter context struct. + * + * ReceiveFlags - Any combination of SK_PROTO_XXX flags of the protocols + * for which the caller wants checksum information on received frames. + * + * pChecksum1Offset - The start offset of the first receive descriptor + * hardware checksum to be calculated for received frames is returned + * here. + * + * pChecksum2Offset - The start offset of the second receive descriptor + * hardware checksum to be calculated for received frames is returned + * here. + * + * Returns: N/A + * Returns the two hardware checksum start offsets. + */ +void SkCsSetReceiveFlags( +SK_AC *pAc, /* Adapter context struct. */ +unsigned ReceiveFlags, /* New receive flags. */ +unsigned *pChecksum1Offset, /* Offset for hardware checksum 1. */ +unsigned *pChecksum2Offset, /* Offset for hardware checksum 2. */ +int NetNumber) +{ + /* Save the receive flags. */ + + pAc->Csum.ReceiveFlags[NetNumber] = ReceiveFlags; + + /* First checksum start offset is the IP header. */ + *pChecksum1Offset = SKCS_MAC_HEADER_SIZE; + + /* + * Second checksum start offset is the IP data. Note that this may vary + * if there are any IP header options in the actual packet. + */ + *pChecksum2Offset = SKCS_MAC_HEADER_SIZE + SKCS_IP_HEADER_SIZE; +} /* SkCsSetReceiveFlags */ + +#ifndef SK_CS_CALCULATE_CHECKSUM + +/****************************************************************************** + * + * SkCsCalculateChecksum - calculate checksum for specified data + * + * Description: + * Calculate and return the 16-bit Internet Checksum for the specified + * data. + * + * Arguments: + * pData - Pointer to data for which the checksum shall be calculated. + * Note: The pointer should be aligned on a 16-bit boundary. + * + * Length - Length in bytes of data to checksum. + * + * Returns: + * The 16-bit Internet Checksum for the specified data. + * + * Note: The checksum is calculated in the machine's natural byte order, + * i.e. little vs. big endian. Thus, the resulting checksum is different + * for the same input data on little and big endian machines. + * + * However, when written back to the network packet, the byte order is + * always in correct network order. + */ +unsigned SkCsCalculateChecksum( +void *pData, /* Data to checksum. */ +unsigned Length) /* Length of data. */ +{ + SK_U16 *pU16; /* Pointer to the data as 16-bit words. */ + unsigned long Checksum; /* Checksum; must be at least 32 bits. */ + + /* Sum up all 16-bit words. */ + + pU16 = (SK_U16 *) pData; + for (Checksum = 0; Length > 1; Length -= 2) { + Checksum += *pU16++; + } + + /* If this is an odd number of bytes, add-in the last byte. */ + + if (Length > 0) { +#ifdef SK_BIG_ENDIAN + /* Add the last byte as the high byte. */ + Checksum += ((unsigned) *(SK_U8 *) pU16) << 8; +#else /* !SK_BIG_ENDIAN */ + /* Add the last byte as the low byte. */ + Checksum += *(SK_U8 *) pU16; +#endif /* !SK_BIG_ENDIAN */ + } + + /* Add-in any carries. */ + + SKCS_OC_ADD(Checksum, Checksum, 0); + + /* Add-in any new carry. */ + + SKCS_OC_ADD(Checksum, Checksum, 0); + + /* Note: All bits beyond the 16-bit limit are now zero. */ + + return ((unsigned) Checksum); +} /* SkCsCalculateChecksum */ + +#endif /* SK_CS_CALCULATE_CHECKSUM */ + +/****************************************************************************** + * + * SkCsEvent - the CSUM event dispatcher + * + * Description: + * This is the event handler for the CSUM module. + * + * Arguments: + * pAc - Pointer to adapter context. + * + * Ioc - I/O context. + * + * Event - Event id. + * + * Param - Event dependent parameter. + * + * Returns: + * The 16-bit Internet Checksum for the specified data. + * + * Note: The checksum is calculated in the machine's natural byte order, + * i.e. little vs. big endian. Thus, the resulting checksum is different + * for the same input data on little and big endian machines. + * + * However, when written back to the network packet, the byte order is + * always in correct network order. + */ +int SkCsEvent( +SK_AC *pAc, /* Pointer to adapter context. */ +SK_IOC Ioc, /* I/O context. */ +SK_U32 Event, /* Event id. */ +SK_EVPARA Param) /* Event dependent parameter. */ +{ + int ProtoIndex; + int NetNumber; + + switch (Event) { + /* + * Clear protocol statistics. + * + * Param - Protocol index, or -1 for all protocols. + * - Net number. + */ + case SK_CSUM_EVENT_CLEAR_PROTO_STATS: + + ProtoIndex = (int)Param.Para32[1]; + NetNumber = (int)Param.Para32[0]; + if (ProtoIndex < 0) { /* Clear for all protocols. */ + if (NetNumber >= 0) { + SK_MEMSET(&pAc->Csum.ProtoStats[NetNumber][0], 0, + sizeof(pAc->Csum.ProtoStats[NetNumber])); + } + } + else { /* Clear for individual protocol. */ + SK_MEMSET(&pAc->Csum.ProtoStats[NetNumber][ProtoIndex], 0, + sizeof(pAc->Csum.ProtoStats[NetNumber][ProtoIndex])); + } + break; + default: + break; + } + return (0); /* Success. */ +} /* SkCsEvent */ + +#endif /* SK_USE_CSUM */ |