[10964] | 1 | /* $Id: ipv4.cpp 98103 2023-01-17 14:15:46Z vboxsync $ */
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| 2 | /** @file
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| 3 | * IPRT - IPv4 Checksum calculation and validation.
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| 4 | */
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| 5 |
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| 6 | /*
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[98103] | 7 | * Copyright (C) 2008-2023 Oracle and/or its affiliates.
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[10964] | 8 | *
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[96407] | 9 | * This file is part of VirtualBox base platform packages, as
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| 10 | * available from https://www.virtualbox.org.
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[10964] | 11 | *
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[96407] | 12 | * This program is free software; you can redistribute it and/or
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| 13 | * modify it under the terms of the GNU General Public License
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| 14 | * as published by the Free Software Foundation, in version 3 of the
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| 15 | * License.
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| 16 | *
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| 17 | * This program is distributed in the hope that it will be useful, but
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| 18 | * WITHOUT ANY WARRANTY; without even the implied warranty of
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| 19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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| 20 | * General Public License for more details.
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| 21 | *
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| 22 | * You should have received a copy of the GNU General Public License
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| 23 | * along with this program; if not, see <https://www.gnu.org/licenses>.
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| 24 | *
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[10964] | 25 | * The contents of this file may alternatively be used under the terms
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| 26 | * of the Common Development and Distribution License Version 1.0
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[96407] | 27 | * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
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| 28 | * in the VirtualBox distribution, in which case the provisions of the
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[10964] | 29 | * CDDL are applicable instead of those of the GPL.
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| 30 | *
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| 31 | * You may elect to license modified versions of this file under the
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| 32 | * terms and conditions of either the GPL or the CDDL or both.
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[96407] | 33 | *
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| 34 | * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
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[10964] | 35 | */
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| 36 |
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[21337] | 37 |
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[57358] | 38 | /*********************************************************************************************************************************
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| 39 | * Header Files *
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| 40 | *********************************************************************************************************************************/
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[10964] | 41 | #include <iprt/net.h>
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[21337] | 42 | #include "internal/iprt.h"
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| 43 |
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[10998] | 44 | #include <iprt/asm.h>
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[10964] | 45 | #include <iprt/assert.h>
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| 46 |
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| 47 |
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| 48 | /**
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| 49 | * Calculates the checksum of the IPv4 header.
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| 50 | *
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[11038] | 51 | * @returns Checksum (network endian).
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[10966] | 52 | * @param pIpHdr Pointer to the IPv4 header to checksum, network endian (big).
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| 53 | * Assumes the caller already checked the minimum size requirement.
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[10964] | 54 | */
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[10982] | 55 | RTDECL(uint16_t) RTNetIPv4HdrChecksum(PCRTNETIPV4 pIpHdr)
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[10964] | 56 | {
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| 57 | uint16_t const *paw = (uint16_t const *)pIpHdr;
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[11013] | 58 | uint32_t u32Sum = paw[0] /* ip_hl */
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| 59 | + paw[1] /* ip_len */
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| 60 | + paw[2] /* ip_id */
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| 61 | + paw[3] /* ip_off */
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| 62 | + paw[4] /* ip_ttl */
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| 63 | /*+ paw[5] == 0 */ /* ip_sum */
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| 64 | + paw[6] /* ip_src */
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| 65 | + paw[7] /* ip_src:16 */
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| 66 | + paw[8] /* ip_dst */
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| 67 | + paw[9]; /* ip_dst:16 */
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[10964] | 68 | /* any options */
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| 69 | if (pIpHdr->ip_hl > 20 / 4)
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| 70 | {
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[10966] | 71 | /* this is a bit insane... (identical to the TCP header) */
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[10964] | 72 | switch (pIpHdr->ip_hl)
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| 73 | {
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[11013] | 74 | case 6: u32Sum += paw[10] + paw[11]; break;
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| 75 | case 7: u32Sum += paw[10] + paw[11] + paw[12] + paw[13]; break;
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| 76 | case 8: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15]; break;
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| 77 | case 9: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17]; break;
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| 78 | case 10: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19]; break;
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| 79 | case 11: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21]; break;
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| 80 | case 12: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23]; break;
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| 81 | case 13: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23] + paw[24] + paw[25]; break;
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| 82 | case 14: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23] + paw[24] + paw[25] + paw[26] + paw[27]; break;
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| 83 | case 15: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23] + paw[24] + paw[25] + paw[26] + paw[27] + paw[28] + paw[29]; break;
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[10964] | 84 | default:
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| 85 | AssertFailed();
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| 86 | }
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| 87 | }
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| 88 |
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| 89 | /* 16-bit one complement fun */
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[11013] | 90 | u32Sum = (u32Sum >> 16) + (u32Sum & 0xffff); /* hi + low words */
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| 91 | u32Sum += u32Sum >> 16; /* carry */
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| 92 | return (uint16_t)~u32Sum;
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[10964] | 93 | }
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[21337] | 94 | RT_EXPORT_SYMBOL(RTNetIPv4HdrChecksum);
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[10964] | 95 |
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| 96 |
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| 97 | /**
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| 98 | * Verifies the header version, header size, packet size, and header checksum
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| 99 | * of the specified IPv4 header.
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| 100 | *
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| 101 | * @returns true if valid, false if invalid.
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[10966] | 102 | * @param pIpHdr Pointer to the IPv4 header to validate. Network endian (big).
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[10964] | 103 | * @param cbHdrMax The max header size, or the max size of what pIpHdr points
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| 104 | * to if you like. Note that an IPv4 header can be up to 60 bytes.
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| 105 | * @param cbPktMax The max IP packet size, IP header and payload. This doesn't have
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| 106 | * to be mapped following pIpHdr.
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[28024] | 107 | * @param fChecksum Whether to validate the checksum (GSO).
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[10964] | 108 | */
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[28024] | 109 | RTDECL(bool) RTNetIPv4IsHdrValid(PCRTNETIPV4 pIpHdr, size_t cbHdrMax, size_t cbPktMax, bool fChecksum)
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[10964] | 110 | {
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[11012] | 111 | /*
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| 112 | * The header fields.
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| 113 | */
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[10964] | 114 | Assert(cbPktMax >= cbHdrMax);
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| 115 | if (RT_UNLIKELY(cbHdrMax < RTNETIPV4_MIN_LEN))
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| 116 | return false;
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| 117 | if (RT_UNLIKELY(pIpHdr->ip_hl * 4 < RTNETIPV4_MIN_LEN))
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| 118 | return false;
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[11313] | 119 | if (RT_UNLIKELY((size_t)pIpHdr->ip_hl * 4 > cbHdrMax))
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[10964] | 120 | {
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[12821] | 121 | Assert((size_t)pIpHdr->ip_hl * 4 > cbPktMax); /* You'll hit this if you mapped/copy too little of the header! */
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[10964] | 122 | return false;
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| 123 | }
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| 124 | if (RT_UNLIKELY(pIpHdr->ip_v != 4))
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| 125 | return false;
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| 126 | if (RT_UNLIKELY(RT_BE2H_U16(pIpHdr->ip_len) > cbPktMax))
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| 127 | return false;
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[11012] | 128 |
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| 129 | /*
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[28024] | 130 | * The header checksum if requested.
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[11012] | 131 | */
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[28024] | 132 | if (fChecksum)
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| 133 | {
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| 134 | uint16_t u16Sum = RTNetIPv4HdrChecksum(pIpHdr);
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| 135 | if (RT_UNLIKELY(pIpHdr->ip_sum != u16Sum))
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| 136 | return false;
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| 137 | }
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[10964] | 138 | return true;
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| 139 | }
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[21337] | 140 | RT_EXPORT_SYMBOL(RTNetIPv4IsHdrValid);
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[10964] | 141 |
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| 142 |
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[10966] | 143 | /**
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[10982] | 144 | * Calculates the checksum of a pseudo header given an IPv4 header [inlined].
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[10966] | 145 | *
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| 146 | * @returns 32-bit intermediary checksum value.
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| 147 | * @param pIpHdr The IP header (network endian (big)).
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| 148 | */
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[10982] | 149 | DECLINLINE(uint32_t) rtNetIPv4PseudoChecksum(PCRTNETIPV4 pIpHdr)
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[10966] | 150 | {
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| 151 | uint16_t cbPayload = RT_BE2H_U16(pIpHdr->ip_len) - pIpHdr->ip_hl * 4;
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[11013] | 152 | uint32_t u32Sum = pIpHdr->ip_src.au16[0]
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| 153 | + pIpHdr->ip_src.au16[1]
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| 154 | + pIpHdr->ip_dst.au16[0]
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| 155 | + pIpHdr->ip_dst.au16[1]
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[10966] | 156 | #ifdef RT_BIG_ENDIAN
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[11013] | 157 | + pIpHdr->ip_p
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[10966] | 158 | #else
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[11013] | 159 | + ((uint32_t)pIpHdr->ip_p << 8)
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[10966] | 160 | #endif
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[11013] | 161 | + RT_H2BE_U16(cbPayload);
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| 162 | return u32Sum;
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[10966] | 163 | }
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| 164 |
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| 165 |
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| 166 | /**
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[10982] | 167 | * Calculates the checksum of a pseudo header given an IPv4 header.
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| 168 | *
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| 169 | * @returns 32-bit intermediary checksum value.
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| 170 | * @param pIpHdr The IP header (network endian (big)).
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| 171 | */
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| 172 | RTDECL(uint32_t) RTNetIPv4PseudoChecksum(PCRTNETIPV4 pIpHdr)
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| 173 | {
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| 174 | return rtNetIPv4PseudoChecksum(pIpHdr);
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| 175 | }
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[21337] | 176 | RT_EXPORT_SYMBOL(RTNetIPv4PseudoChecksum);
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[10982] | 177 |
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| 178 |
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| 179 | /**
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[10966] | 180 | * Calculates the checksum of a pseudo header given the individual components.
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| 181 | *
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| 182 | * @returns 32-bit intermediary checksum value.
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| 183 | * @param SrcAddr The source address in host endian.
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| 184 | * @param DstAddr The destination address in host endian.
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| 185 | * @param bProtocol The protocol number.
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| 186 | * @param cbPkt The packet size (host endian of course) (no IPv4 header).
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| 187 | */
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| 188 | RTDECL(uint32_t) RTNetIPv4PseudoChecksumBits(RTNETADDRIPV4 SrcAddr, RTNETADDRIPV4 DstAddr, uint8_t bProtocol, uint16_t cbPkt)
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| 189 | {
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[11013] | 190 | uint32_t u32Sum = RT_H2BE_U16(SrcAddr.au16[0])
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| 191 | + RT_H2BE_U16(SrcAddr.au16[1])
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| 192 | + RT_H2BE_U16(DstAddr.au16[0])
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| 193 | + RT_H2BE_U16(DstAddr.au16[1])
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[10966] | 194 | #ifdef RT_BIG_ENDIAN
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[11013] | 195 | + bProtocol
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[10966] | 196 | #else
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[11013] | 197 | + ((uint32_t)bProtocol << 8)
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[10966] | 198 | #endif
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[11013] | 199 | + RT_H2BE_U16(cbPkt);
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| 200 | return u32Sum;
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[10966] | 201 | }
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[21337] | 202 | RT_EXPORT_SYMBOL(RTNetIPv4PseudoChecksumBits);
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[10966] | 203 |
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| 204 |
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| 205 | /**
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[10982] | 206 | * Adds the checksum of the UDP header to the intermediate checksum value [inlined].
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[10966] | 207 | *
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| 208 | * @returns 32-bit intermediary checksum value.
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| 209 | * @param pUdpHdr Pointer to the UDP header to checksum, network endian (big).
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[11013] | 210 | * @param u32Sum The 32-bit intermediate checksum value.
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[10966] | 211 | */
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[11013] | 212 | DECLINLINE(uint32_t) rtNetIPv4AddUDPChecksum(PCRTNETUDP pUdpHdr, uint32_t u32Sum)
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[10966] | 213 | {
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[11013] | 214 | u32Sum += pUdpHdr->uh_sport
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| 215 | + pUdpHdr->uh_dport
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| 216 | /*+ pUdpHdr->uh_sum = 0 */
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| 217 | + pUdpHdr->uh_ulen;
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| 218 | return u32Sum;
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[10966] | 219 | }
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| 220 |
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| 221 |
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| 222 | /**
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[10982] | 223 | * Adds the checksum of the UDP header to the intermediate checksum value.
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[10966] | 224 | *
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| 225 | * @returns 32-bit intermediary checksum value.
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[10982] | 226 | * @param pUdpHdr Pointer to the UDP header to checksum, network endian (big).
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[11013] | 227 | * @param u32Sum The 32-bit intermediate checksum value.
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[10982] | 228 | */
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[11013] | 229 | RTDECL(uint32_t) RTNetIPv4AddUDPChecksum(PCRTNETUDP pUdpHdr, uint32_t u32Sum)
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[10982] | 230 | {
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[11013] | 231 | return rtNetIPv4AddUDPChecksum(pUdpHdr, u32Sum);
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[10982] | 232 | }
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[21337] | 233 | RT_EXPORT_SYMBOL(RTNetIPv4AddUDPChecksum);
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[10982] | 234 |
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| 235 |
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| 236 | /**
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| 237 | * Adds the checksum of the TCP header to the intermediate checksum value [inlined].
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| 238 | *
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| 239 | * @returns 32-bit intermediary checksum value.
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[25645] | 240 | * @param pTcpHdr Pointer to the TCP header to checksum, network
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[33540] | 241 | * endian (big). Assumes the caller has already validate
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[25645] | 242 | * it and made sure the entire header is present.
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[11013] | 243 | * @param u32Sum The 32-bit intermediate checksum value.
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[10966] | 244 | */
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[11013] | 245 | DECLINLINE(uint32_t) rtNetIPv4AddTCPChecksum(PCRTNETTCP pTcpHdr, uint32_t u32Sum)
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[10966] | 246 | {
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| 247 | uint16_t const *paw = (uint16_t const *)pTcpHdr;
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[11013] | 248 | u32Sum += paw[0] /* th_sport */
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| 249 | + paw[1] /* th_dport */
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| 250 | + paw[2] /* th_seq */
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| 251 | + paw[3] /* th_seq:16 */
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| 252 | + paw[4] /* th_ack */
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| 253 | + paw[5] /* th_ack:16 */
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| 254 | + paw[6] /* th_off, th_x2, th_flags */
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| 255 | + paw[7] /* th_win */
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| 256 | /*+ paw[8] == 0 */ /* th_sum */
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| 257 | + paw[9]; /* th_urp */
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[10966] | 258 | if (pTcpHdr->th_off > RTNETTCP_MIN_LEN / 4)
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| 259 | {
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| 260 | /* this is a bit insane... (identical to the IPv4 header) */
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| 261 | switch (pTcpHdr->th_off)
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| 262 | {
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[11013] | 263 | case 6: u32Sum += paw[10] + paw[11]; break;
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| 264 | case 7: u32Sum += paw[10] + paw[11] + paw[12] + paw[13]; break;
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| 265 | case 8: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15]; break;
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| 266 | case 9: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17]; break;
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| 267 | case 10: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19]; break;
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| 268 | case 11: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21]; break;
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| 269 | case 12: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23]; break;
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| 270 | case 13: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23] + paw[24] + paw[25]; break;
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| 271 | case 14: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23] + paw[24] + paw[25] + paw[26] + paw[27]; break;
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| 272 | case 15: u32Sum += paw[10] + paw[11] + paw[12] + paw[13] + paw[14] + paw[15] + paw[16] + paw[17] + paw[18] + paw[19] + paw[20] + paw[21] + paw[22] + paw[23] + paw[24] + paw[25] + paw[26] + paw[27] + paw[28] + paw[29]; break;
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[10966] | 273 | default:
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| 274 | AssertFailed();
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| 275 | }
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| 276 | }
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| 277 |
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[11013] | 278 | return u32Sum;
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[10966] | 279 | }
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| 280 |
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| 281 |
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| 282 | /**
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[10982] | 283 | * Adds the checksum of the TCP header to the intermediate checksum value.
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[10966] | 284 | *
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| 285 | * @returns 32-bit intermediary checksum value.
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[25645] | 286 | * @param pTcpHdr Pointer to the TCP header to checksum, network
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[33540] | 287 | * endian (big). Assumes the caller has already validate
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[25645] | 288 | * it and made sure the entire header is present.
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[11013] | 289 | * @param u32Sum The 32-bit intermediate checksum value.
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[10982] | 290 | */
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[11013] | 291 | RTDECL(uint32_t) RTNetIPv4AddTCPChecksum(PCRTNETTCP pTcpHdr, uint32_t u32Sum)
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[10982] | 292 | {
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[11013] | 293 | return rtNetIPv4AddTCPChecksum(pTcpHdr, u32Sum);
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[10982] | 294 | }
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[21337] | 295 | RT_EXPORT_SYMBOL(RTNetIPv4AddTCPChecksum);
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[10982] | 296 |
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| 297 |
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| 298 | /**
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| 299 | * Adds the checksum of the specified data segment to the intermediate checksum value [inlined].
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| 300 | *
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| 301 | * @returns 32-bit intermediary checksum value.
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[25645] | 302 | * @param pvData Pointer to the data that should be checksummed.
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| 303 | * @param cbData The number of bytes to checksum.
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[11013] | 304 | * @param u32Sum The 32-bit intermediate checksum value.
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[10966] | 305 | * @param pfOdd This is used to keep track of odd bits, initialize to false
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| 306 | * when starting to checksum the data (aka text) after a TCP
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| 307 | * or UDP header (data never start at an odd offset).
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| 308 | */
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[11013] | 309 | DECLINLINE(uint32_t) rtNetIPv4AddDataChecksum(void const *pvData, size_t cbData, uint32_t u32Sum, bool *pfOdd)
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[10966] | 310 | {
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| 311 | if (*pfOdd)
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| 312 | {
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| 313 | #ifdef RT_BIG_ENDIAN
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| 314 | /* there was an odd byte in the previous chunk, add the lower byte. */
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[11013] | 315 | u32Sum += *(uint8_t *)pvData;
|
---|
[10966] | 316 | #else
|
---|
| 317 | /* there was an odd byte in the previous chunk, add the upper byte. */
|
---|
[11013] | 318 | u32Sum += (uint32_t)*(uint8_t *)pvData << 8;
|
---|
[10966] | 319 | #endif
|
---|
| 320 | /* skip the byte. */
|
---|
| 321 | cbData--;
|
---|
| 322 | if (!cbData)
|
---|
[11013] | 323 | return u32Sum;
|
---|
[10966] | 324 | pvData = (uint8_t const *)pvData + 1;
|
---|
| 325 | }
|
---|
| 326 |
|
---|
| 327 | /* iterate the data. */
|
---|
[93040] | 328 | uint16_t const *pw = (uint16_t const *)pvData;
|
---|
[10966] | 329 | while (cbData > 1)
|
---|
| 330 | {
|
---|
[11013] | 331 | u32Sum += *pw;
|
---|
[10982] | 332 | pw++;
|
---|
[10966] | 333 | cbData -= 2;
|
---|
| 334 | }
|
---|
| 335 |
|
---|
| 336 | /* handle odd byte. */
|
---|
| 337 | if (cbData)
|
---|
| 338 | {
|
---|
| 339 | #ifdef RT_BIG_ENDIAN
|
---|
[11013] | 340 | u32Sum += (uint32_t)*(uint8_t *)pw << 8;
|
---|
[10966] | 341 | #else
|
---|
[11013] | 342 | u32Sum += *(uint8_t *)pw;
|
---|
[10966] | 343 | #endif
|
---|
| 344 | *pfOdd = true;
|
---|
| 345 | }
|
---|
| 346 | else
|
---|
| 347 | *pfOdd = false;
|
---|
[11013] | 348 | return u32Sum;
|
---|
[10966] | 349 | }
|
---|
| 350 |
|
---|
[10982] | 351 | /**
|
---|
| 352 | * Adds the checksum of the specified data segment to the intermediate checksum value.
|
---|
| 353 | *
|
---|
| 354 | * @returns 32-bit intermediary checksum value.
|
---|
[25645] | 355 | * @param pvData The data bits to checksum.
|
---|
| 356 | * @param cbData The number of bytes to checksum.
|
---|
[11013] | 357 | * @param u32Sum The 32-bit intermediate checksum value.
|
---|
[10982] | 358 | * @param pfOdd This is used to keep track of odd bits, initialize to false
|
---|
| 359 | * when starting to checksum the data (aka text) after a TCP
|
---|
| 360 | * or UDP header (data never start at an odd offset).
|
---|
| 361 | */
|
---|
[11013] | 362 | RTDECL(uint32_t) RTNetIPv4AddDataChecksum(void const *pvData, size_t cbData, uint32_t u32Sum, bool *pfOdd)
|
---|
[10982] | 363 | {
|
---|
[11013] | 364 | return rtNetIPv4AddDataChecksum(pvData, cbData, u32Sum, pfOdd);
|
---|
[10982] | 365 | }
|
---|
[21337] | 366 | RT_EXPORT_SYMBOL(RTNetIPv4AddDataChecksum);
|
---|
[10966] | 367 |
|
---|
[10982] | 368 |
|
---|
[10966] | 369 | /**
|
---|
[10982] | 370 | * Finalizes a IPv4 checksum [inlined].
|
---|
[10966] | 371 | *
|
---|
[11038] | 372 | * @returns The checksum (network endian).
|
---|
[11013] | 373 | * @param u32Sum The 32-bit intermediate checksum value.
|
---|
[10966] | 374 | */
|
---|
[11013] | 375 | DECLINLINE(uint16_t) rtNetIPv4FinalizeChecksum(uint32_t u32Sum)
|
---|
[10966] | 376 | {
|
---|
| 377 | /* 16-bit one complement fun */
|
---|
[11013] | 378 | u32Sum = (u32Sum >> 16) + (u32Sum & 0xffff); /* hi + low words */
|
---|
| 379 | u32Sum += u32Sum >> 16; /* carry */
|
---|
| 380 | return (uint16_t)~u32Sum;
|
---|
[10966] | 381 | }
|
---|
| 382 |
|
---|
| 383 |
|
---|
[10982] | 384 | /**
|
---|
| 385 | * Finalizes a IPv4 checksum.
|
---|
| 386 | *
|
---|
[11038] | 387 | * @returns The checksum (network endian).
|
---|
[11013] | 388 | * @param u32Sum The 32-bit intermediate checksum value.
|
---|
[10982] | 389 | */
|
---|
[11013] | 390 | RTDECL(uint16_t) RTNetIPv4FinalizeChecksum(uint32_t u32Sum)
|
---|
[10982] | 391 | {
|
---|
[11013] | 392 | return rtNetIPv4FinalizeChecksum(u32Sum);
|
---|
[10982] | 393 | }
|
---|
[21337] | 394 | RT_EXPORT_SYMBOL(RTNetIPv4FinalizeChecksum);
|
---|
[10966] | 395 |
|
---|
[10982] | 396 |
|
---|
| 397 | /**
|
---|
[28024] | 398 | * Calculates the checksum for the UDP header given the UDP header w/ payload
|
---|
| 399 | * and the checksum of the pseudo header.
|
---|
| 400 | *
|
---|
| 401 | * @returns The checksum (network endian).
|
---|
| 402 | * @param u32Sum The checksum of the pseudo header. See
|
---|
| 403 | * RTNetIPv4PseudoChecksum and RTNetIPv6PseudoChecksum.
|
---|
| 404 | * @param pUdpHdr Pointer to the UDP header and the payload, in
|
---|
| 405 | * network endian (big). We use the uh_ulen field to
|
---|
| 406 | * figure out how much to checksum.
|
---|
| 407 | */
|
---|
| 408 | RTDECL(uint16_t) RTNetUDPChecksum(uint32_t u32Sum, PCRTNETUDP pUdpHdr)
|
---|
| 409 | {
|
---|
[32257] | 410 | bool fOdd;
|
---|
[28024] | 411 | u32Sum = rtNetIPv4AddUDPChecksum(pUdpHdr, u32Sum);
|
---|
[32257] | 412 | fOdd = false;
|
---|
[28024] | 413 | u32Sum = rtNetIPv4AddDataChecksum(pUdpHdr + 1, RT_BE2H_U16(pUdpHdr->uh_ulen) - sizeof(*pUdpHdr), u32Sum, &fOdd);
|
---|
| 414 | return rtNetIPv4FinalizeChecksum(u32Sum);
|
---|
| 415 | }
|
---|
| 416 | RT_EXPORT_SYMBOL(RTNetUDPChecksum);
|
---|
| 417 |
|
---|
| 418 |
|
---|
| 419 | /**
|
---|
[10982] | 420 | * Calculates the checksum for the UDP header given the IP header,
|
---|
| 421 | * UDP header and payload.
|
---|
| 422 | *
|
---|
[11038] | 423 | * @returns The checksum (network endian).
|
---|
[10982] | 424 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 425 | * @param pUdpHdr Pointer to the UDP header, in network endian (big).
|
---|
| 426 | * @param pvData Pointer to the UDP payload. The size is taken from the
|
---|
| 427 | * UDP header and the caller is supposed to have validated
|
---|
| 428 | * this before calling.
|
---|
| 429 | */
|
---|
| 430 | RTDECL(uint16_t) RTNetIPv4UDPChecksum(PCRTNETIPV4 pIpHdr, PCRTNETUDP pUdpHdr, void const *pvData)
|
---|
| 431 | {
|
---|
[32257] | 432 | bool fOdd;
|
---|
[11013] | 433 | uint32_t u32Sum = rtNetIPv4PseudoChecksum(pIpHdr);
|
---|
| 434 | u32Sum = rtNetIPv4AddUDPChecksum(pUdpHdr, u32Sum);
|
---|
[32257] | 435 | fOdd = false;
|
---|
[11013] | 436 | u32Sum = rtNetIPv4AddDataChecksum(pvData, RT_BE2H_U16(pUdpHdr->uh_ulen) - sizeof(*pUdpHdr), u32Sum, &fOdd);
|
---|
| 437 | return rtNetIPv4FinalizeChecksum(u32Sum);
|
---|
[10982] | 438 | }
|
---|
[21337] | 439 | RT_EXPORT_SYMBOL(RTNetIPv4UDPChecksum);
|
---|
[10982] | 440 |
|
---|
| 441 |
|
---|
[11012] | 442 | /**
|
---|
[33540] | 443 | * Simple verification of an UDP packet size.
|
---|
[11012] | 444 | *
|
---|
| 445 | * @returns true if valid, false if invalid.
|
---|
| 446 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 447 | * This is assumed to be valid and the minimum size being mapped.
|
---|
| 448 | * @param pUdpHdr Pointer to the UDP header, in network endian (big).
|
---|
| 449 | * @param cbPktMax The max UDP packet size, UDP header and payload (data).
|
---|
| 450 | */
|
---|
| 451 | DECLINLINE(bool) rtNetIPv4IsUDPSizeValid(PCRTNETIPV4 pIpHdr, PCRTNETUDP pUdpHdr, size_t cbPktMax)
|
---|
| 452 | {
|
---|
| 453 | /*
|
---|
| 454 | * Size validation.
|
---|
| 455 | */
|
---|
[32257] | 456 | size_t cb;
|
---|
[11012] | 457 | if (RT_UNLIKELY(cbPktMax < RTNETUDP_MIN_LEN))
|
---|
| 458 | return false;
|
---|
[32257] | 459 | cb = RT_BE2H_U16(pUdpHdr->uh_ulen);
|
---|
[11012] | 460 | if (RT_UNLIKELY(cb > cbPktMax))
|
---|
| 461 | return false;
|
---|
[11313] | 462 | if (RT_UNLIKELY(cb > (size_t)(RT_BE2H_U16(pIpHdr->ip_len) - pIpHdr->ip_hl * 4)))
|
---|
[11012] | 463 | return false;
|
---|
| 464 | return true;
|
---|
| 465 | }
|
---|
| 466 |
|
---|
| 467 |
|
---|
| 468 | /**
|
---|
[33540] | 469 | * Simple verification of an UDP packet size.
|
---|
[11012] | 470 | *
|
---|
| 471 | * @returns true if valid, false if invalid.
|
---|
| 472 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 473 | * This is assumed to be valid and the minimum size being mapped.
|
---|
| 474 | * @param pUdpHdr Pointer to the UDP header, in network endian (big).
|
---|
| 475 | * @param cbPktMax The max UDP packet size, UDP header and payload (data).
|
---|
| 476 | */
|
---|
| 477 | RTDECL(bool) RTNetIPv4IsUDPSizeValid(PCRTNETIPV4 pIpHdr, PCRTNETUDP pUdpHdr, size_t cbPktMax)
|
---|
| 478 | {
|
---|
| 479 | return rtNetIPv4IsUDPSizeValid(pIpHdr, pUdpHdr, cbPktMax);
|
---|
| 480 | }
|
---|
[21337] | 481 | RT_EXPORT_SYMBOL(RTNetIPv4IsUDPSizeValid);
|
---|
[11012] | 482 |
|
---|
| 483 |
|
---|
| 484 | /**
|
---|
[33540] | 485 | * Simple verification of an UDP packet (size + checksum).
|
---|
[11012] | 486 | *
|
---|
| 487 | * @returns true if valid, false if invalid.
|
---|
| 488 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 489 | * This is assumed to be valid and the minimum size being mapped.
|
---|
| 490 | * @param pUdpHdr Pointer to the UDP header, in network endian (big).
|
---|
| 491 | * @param pvData Pointer to the data, assuming it's one single segment
|
---|
| 492 | * and that cbPktMax - sizeof(RTNETUDP) is mapped here.
|
---|
| 493 | * @param cbPktMax The max UDP packet size, UDP header and payload (data).
|
---|
[28024] | 494 | * @param fChecksum Whether to validate the checksum (GSO).
|
---|
[11012] | 495 | */
|
---|
[28024] | 496 | RTDECL(bool) RTNetIPv4IsUDPValid(PCRTNETIPV4 pIpHdr, PCRTNETUDP pUdpHdr, void const *pvData, size_t cbPktMax, bool fChecksum)
|
---|
[11012] | 497 | {
|
---|
| 498 | if (RT_UNLIKELY(!rtNetIPv4IsUDPSizeValid(pIpHdr, pUdpHdr, cbPktMax)))
|
---|
| 499 | return false;
|
---|
[28024] | 500 | if (fChecksum && pUdpHdr->uh_sum)
|
---|
[11060] | 501 | {
|
---|
| 502 | uint16_t u16Sum = RTNetIPv4UDPChecksum(pIpHdr, pUdpHdr, pvData);
|
---|
| 503 | if (RT_UNLIKELY(pUdpHdr->uh_sum != u16Sum))
|
---|
| 504 | return false;
|
---|
| 505 | }
|
---|
[11012] | 506 | return true;
|
---|
| 507 | }
|
---|
[21337] | 508 | RT_EXPORT_SYMBOL(RTNetIPv4IsUDPValid);
|
---|
[11038] | 509 |
|
---|
| 510 |
|
---|
[11044] | 511 | /**
|
---|
| 512 | * Calculates the checksum for the TCP header given the IP header,
|
---|
| 513 | * TCP header and payload.
|
---|
| 514 | *
|
---|
| 515 | * @returns The checksum (network endian).
|
---|
| 516 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 517 | * @param pTcpHdr Pointer to the TCP header, in network endian (big).
|
---|
[28024] | 518 | * @param pvData Pointer to the TCP payload. The size is derived from
|
---|
| 519 | * the two headers and the caller is supposed to have
|
---|
| 520 | * validated this before calling. If NULL, we assume
|
---|
| 521 | * the data follows immediately after the TCP header.
|
---|
[11044] | 522 | */
|
---|
| 523 | RTDECL(uint16_t) RTNetIPv4TCPChecksum(PCRTNETIPV4 pIpHdr, PCRTNETTCP pTcpHdr, void const *pvData)
|
---|
| 524 | {
|
---|
[32257] | 525 | bool fOdd;
|
---|
| 526 | size_t cbData;
|
---|
[11044] | 527 | uint32_t u32Sum = rtNetIPv4PseudoChecksum(pIpHdr);
|
---|
| 528 | u32Sum = rtNetIPv4AddTCPChecksum(pTcpHdr, u32Sum);
|
---|
[32257] | 529 | fOdd = false;
|
---|
| 530 | cbData = RT_BE2H_U16(pIpHdr->ip_len) - pIpHdr->ip_hl * 4 - pTcpHdr->th_off * 4;
|
---|
[11044] | 531 | u32Sum = rtNetIPv4AddDataChecksum(pvData ? pvData : (uint8_t const *)pTcpHdr + pTcpHdr->th_off * 4,
|
---|
| 532 | cbData, u32Sum, &fOdd);
|
---|
| 533 | return rtNetIPv4FinalizeChecksum(u32Sum);
|
---|
| 534 | }
|
---|
[21337] | 535 | RT_EXPORT_SYMBOL(RTNetIPv4TCPChecksum);
|
---|
[11044] | 536 |
|
---|
| 537 |
|
---|
| 538 | /**
|
---|
[28024] | 539 | * Calculates the checksum for the TCP header given the TCP header, payload and
|
---|
| 540 | * the checksum of the pseudo header.
|
---|
| 541 | *
|
---|
| 542 | * This is not specific to IPv4.
|
---|
| 543 | *
|
---|
| 544 | * @returns The checksum (network endian).
|
---|
| 545 | * @param u32Sum The checksum of the pseudo header. See
|
---|
| 546 | * RTNetIPv4PseudoChecksum and RTNetIPv6PseudoChecksum.
|
---|
| 547 | * @param pTcpHdr Pointer to the TCP header, in network endian (big).
|
---|
| 548 | * @param pvData Pointer to the TCP payload.
|
---|
| 549 | * @param cbData The size of the TCP payload.
|
---|
| 550 | */
|
---|
| 551 | RTDECL(uint16_t) RTNetTCPChecksum(uint32_t u32Sum, PCRTNETTCP pTcpHdr, void const *pvData, size_t cbData)
|
---|
| 552 | {
|
---|
[32257] | 553 | bool fOdd;
|
---|
[28024] | 554 | u32Sum = rtNetIPv4AddTCPChecksum(pTcpHdr, u32Sum);
|
---|
[32257] | 555 | fOdd = false;
|
---|
[28024] | 556 | u32Sum = rtNetIPv4AddDataChecksum(pvData, cbData, u32Sum, &fOdd);
|
---|
| 557 | return rtNetIPv4FinalizeChecksum(u32Sum);
|
---|
| 558 | }
|
---|
| 559 | RT_EXPORT_SYMBOL(RTNetTCPChecksum);
|
---|
| 560 |
|
---|
| 561 |
|
---|
| 562 | /**
|
---|
[33540] | 563 | * Verification of a TCP header.
|
---|
[11044] | 564 | *
|
---|
| 565 | * @returns true if valid, false if invalid.
|
---|
| 566 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 567 | * This is assumed to be valid and the minimum size being mapped.
|
---|
| 568 | * @param pTcpHdr Pointer to the TCP header, in network endian (big).
|
---|
| 569 | * @param cbHdrMax The max TCP header size (what pTcpHdr points to).
|
---|
| 570 | * @param cbPktMax The max TCP packet size, TCP header and payload (data).
|
---|
| 571 | */
|
---|
| 572 | DECLINLINE(bool) rtNetIPv4IsTCPSizeValid(PCRTNETIPV4 pIpHdr, PCRTNETTCP pTcpHdr, size_t cbHdrMax, size_t cbPktMax)
|
---|
| 573 | {
|
---|
[32257] | 574 | size_t cbTcpHdr;
|
---|
| 575 | size_t cbTcp;
|
---|
| 576 |
|
---|
[11044] | 577 | Assert(cbPktMax >= cbHdrMax);
|
---|
| 578 |
|
---|
| 579 | /*
|
---|
| 580 | * Size validations.
|
---|
| 581 | */
|
---|
| 582 | if (RT_UNLIKELY(cbPktMax < RTNETTCP_MIN_LEN))
|
---|
| 583 | return false;
|
---|
[32257] | 584 | cbTcpHdr = pTcpHdr->th_off * 4;
|
---|
[11044] | 585 | if (RT_UNLIKELY(cbTcpHdr > cbHdrMax))
|
---|
| 586 | return false;
|
---|
[32257] | 587 | cbTcp = RT_BE2H_U16(pIpHdr->ip_len) - pIpHdr->ip_hl * 4;
|
---|
[11044] | 588 | if (RT_UNLIKELY(cbTcp > cbPktMax))
|
---|
| 589 | return false;
|
---|
| 590 | return true;
|
---|
| 591 | }
|
---|
| 592 |
|
---|
| 593 |
|
---|
| 594 | /**
|
---|
[33540] | 595 | * Simple verification of an TCP packet size.
|
---|
[11044] | 596 | *
|
---|
| 597 | * @returns true if valid, false if invalid.
|
---|
| 598 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 599 | * This is assumed to be valid and the minimum size being mapped.
|
---|
| 600 | * @param pTcpHdr Pointer to the TCP header, in network endian (big).
|
---|
| 601 | * @param cbHdrMax The max TCP header size (what pTcpHdr points to).
|
---|
| 602 | * @param cbPktMax The max TCP packet size, TCP header and payload (data).
|
---|
| 603 | */
|
---|
| 604 | RTDECL(bool) RTNetIPv4IsTCPSizeValid(PCRTNETIPV4 pIpHdr, PCRTNETTCP pTcpHdr, size_t cbHdrMax, size_t cbPktMax)
|
---|
| 605 | {
|
---|
| 606 | return rtNetIPv4IsTCPSizeValid(pIpHdr, pTcpHdr, cbHdrMax, cbPktMax);
|
---|
| 607 | }
|
---|
[21337] | 608 | RT_EXPORT_SYMBOL(RTNetIPv4IsTCPSizeValid);
|
---|
[11044] | 609 |
|
---|
| 610 |
|
---|
| 611 | /**
|
---|
[33540] | 612 | * Simple verification of an TCP packet (size + checksum).
|
---|
[11044] | 613 | *
|
---|
| 614 | * @returns true if valid, false if invalid.
|
---|
| 615 | * @param pIpHdr Pointer to the IPv4 header, in network endian (big).
|
---|
| 616 | * This is assumed to be valid and the minimum size being mapped.
|
---|
| 617 | * @param pTcpHdr Pointer to the TCP header, in network endian (big).
|
---|
| 618 | * @param cbHdrMax The max TCP header size (what pTcpHdr points to).
|
---|
| 619 | * @param pvData Pointer to the data, assuming it's one single segment
|
---|
| 620 | * and that cbPktMax - sizeof(RTNETTCP) is mapped here.
|
---|
| 621 | * If NULL then we assume the data follows immediately after
|
---|
| 622 | * the TCP header.
|
---|
| 623 | * @param cbPktMax The max TCP packet size, TCP header and payload (data).
|
---|
[28024] | 624 | * @param fChecksum Whether to validate the checksum (GSO).
|
---|
[11044] | 625 | */
|
---|
[28024] | 626 | RTDECL(bool) RTNetIPv4IsTCPValid(PCRTNETIPV4 pIpHdr, PCRTNETTCP pTcpHdr, size_t cbHdrMax, void const *pvData, size_t cbPktMax,
|
---|
| 627 | bool fChecksum)
|
---|
[11044] | 628 | {
|
---|
| 629 | if (RT_UNLIKELY(!rtNetIPv4IsTCPSizeValid(pIpHdr, pTcpHdr, cbHdrMax, cbPktMax)))
|
---|
| 630 | return false;
|
---|
[28024] | 631 | if (fChecksum)
|
---|
| 632 | {
|
---|
| 633 | uint16_t u16Sum = RTNetIPv4TCPChecksum(pIpHdr, pTcpHdr, pvData);
|
---|
| 634 | if (RT_UNLIKELY(pTcpHdr->th_sum != u16Sum))
|
---|
| 635 | return false;
|
---|
| 636 | }
|
---|
[11044] | 637 | return true;
|
---|
| 638 | }
|
---|
[21337] | 639 | RT_EXPORT_SYMBOL(RTNetIPv4IsTCPValid);
|
---|
[11044] | 640 |
|
---|
[11049] | 641 |
|
---|
| 642 | /**
|
---|
| 643 | * Minimal validation of a DHCP packet.
|
---|
| 644 | *
|
---|
| 645 | * This will fail on BOOTP packets (if sufficient data is supplied).
|
---|
| 646 | * It will not verify the source and destination ports, that's the
|
---|
| 647 | * caller's responsibility.
|
---|
| 648 | *
|
---|
| 649 | * This function will ASSUME that the hardware type is ethernet
|
---|
| 650 | * and use that for htype/hlen validation.
|
---|
| 651 | *
|
---|
| 652 | * @returns true if valid, false if invalid.
|
---|
| 653 | * @param pUdpHdr Pointer to the UDP header, in network endian (big).
|
---|
| 654 | * This is assumed to be valid and fully mapped.
|
---|
| 655 | * @param pDhcp Pointer to the DHCP packet.
|
---|
| 656 | * This might not be the entire thing, see cbDhcp.
|
---|
| 657 | * @param cbDhcp The number of valid bytes that pDhcp points to.
|
---|
| 658 | * @param pMsgType Where to store the message type (if found).
|
---|
| 659 | * This will be set to 0 if not found and on failure.
|
---|
| 660 | */
|
---|
| 661 | RTDECL(bool) RTNetIPv4IsDHCPValid(PCRTNETUDP pUdpHdr, PCRTNETBOOTP pDhcp, size_t cbDhcp, uint8_t *pMsgType)
|
---|
| 662 | {
|
---|
[39080] | 663 | ssize_t cbLeft;
|
---|
| 664 | uint8_t MsgType;
|
---|
| 665 | PCRTNETDHCPOPT pOpt;
|
---|
| 666 | NOREF(pUdpHdr); /** @todo rainy-day: Why isn't the UDP header used? */
|
---|
[32257] | 667 |
|
---|
[11049] | 668 | AssertPtrNull(pMsgType);
|
---|
| 669 | if (pMsgType)
|
---|
| 670 | *pMsgType = 0;
|
---|
| 671 |
|
---|
| 672 | /*
|
---|
| 673 | * Validate all the header fields we're able to...
|
---|
| 674 | */
|
---|
[73097] | 675 | if (cbDhcp < RT_UOFFSETOF(RTNETBOOTP, bp_op) + sizeof(pDhcp->bp_op))
|
---|
[11049] | 676 | return true;
|
---|
| 677 | if (RT_UNLIKELY( pDhcp->bp_op != RTNETBOOTP_OP_REQUEST
|
---|
| 678 | && pDhcp->bp_op != RTNETBOOTP_OP_REPLY))
|
---|
| 679 | return false;
|
---|
| 680 |
|
---|
[73097] | 681 | if (cbDhcp < RT_UOFFSETOF(RTNETBOOTP, bp_htype) + sizeof(pDhcp->bp_htype))
|
---|
[11049] | 682 | return true;
|
---|
| 683 | if (RT_UNLIKELY(pDhcp->bp_htype != RTNET_ARP_ETHER))
|
---|
| 684 | return false;
|
---|
| 685 |
|
---|
[73097] | 686 | if (cbDhcp < RT_UOFFSETOF(RTNETBOOTP, bp_hlen) + sizeof(pDhcp->bp_hlen))
|
---|
[11049] | 687 | return true;
|
---|
| 688 | if (RT_UNLIKELY(pDhcp->bp_hlen != sizeof(RTMAC)))
|
---|
| 689 | return false;
|
---|
| 690 |
|
---|
[73097] | 691 | if (cbDhcp < RT_UOFFSETOF(RTNETBOOTP, bp_flags) + sizeof(pDhcp->bp_flags))
|
---|
[11049] | 692 | return true;
|
---|
| 693 | if (RT_UNLIKELY(RT_BE2H_U16(pDhcp->bp_flags) & ~(RTNET_DHCP_FLAGS_NO_BROADCAST)))
|
---|
| 694 | return false;
|
---|
| 695 |
|
---|
| 696 | /*
|
---|
| 697 | * Check the DHCP cookie and make sure it isn't followed by an END option
|
---|
| 698 | * (because that seems to be indicating that it's BOOTP and not DHCP).
|
---|
| 699 | */
|
---|
[73097] | 700 | cbLeft = (ssize_t)cbDhcp - RT_UOFFSETOF(RTNETBOOTP, bp_vend.Dhcp.dhcp_cookie) + sizeof(pDhcp->bp_vend.Dhcp.dhcp_cookie);
|
---|
[11049] | 701 | if (cbLeft < 0)
|
---|
| 702 | return true;
|
---|
| 703 | if (RT_UNLIKELY(RT_BE2H_U32(pDhcp->bp_vend.Dhcp.dhcp_cookie) != RTNET_DHCP_COOKIE))
|
---|
| 704 | return false;
|
---|
| 705 | if (cbLeft < 1)
|
---|
| 706 | return true;
|
---|
[32257] | 707 | pOpt = (PCRTNETDHCPOPT)&pDhcp->bp_vend.Dhcp.dhcp_opts[0];
|
---|
[11049] | 708 | if (pOpt->dhcp_opt == RTNET_DHCP_OPT_END)
|
---|
| 709 | return false;
|
---|
| 710 |
|
---|
| 711 | /*
|
---|
| 712 | * Scan the options until we find the message type or run out of message.
|
---|
| 713 | *
|
---|
| 714 | * We're not strict about termination (END) for many reasons, however,
|
---|
| 715 | * we don't accept END without MSG_TYPE.
|
---|
| 716 | */
|
---|
[32257] | 717 | MsgType = 0;
|
---|
[11049] | 718 | while (cbLeft > 0)
|
---|
| 719 | {
|
---|
| 720 | if (pOpt->dhcp_opt == RTNET_DHCP_OPT_END)
|
---|
| 721 | {
|
---|
| 722 | /* Fail if no MSG_TYPE. */
|
---|
| 723 | if (!MsgType)
|
---|
| 724 | return false;
|
---|
| 725 | break;
|
---|
| 726 | }
|
---|
| 727 | if (pOpt->dhcp_opt == RTNET_DHCP_OPT_PAD)
|
---|
| 728 | {
|
---|
| 729 | pOpt = (PCRTNETDHCPOPT)((uint8_t const *)pOpt + 1);
|
---|
| 730 | cbLeft--;
|
---|
| 731 | }
|
---|
| 732 | else
|
---|
| 733 | {
|
---|
| 734 | switch (pOpt->dhcp_opt)
|
---|
| 735 | {
|
---|
| 736 | case RTNET_DHCP_OPT_MSG_TYPE:
|
---|
| 737 | {
|
---|
| 738 | if (cbLeft < 3)
|
---|
| 739 | return true;
|
---|
| 740 | MsgType = *(const uint8_t *)(pOpt + 1);
|
---|
| 741 | switch (MsgType)
|
---|
| 742 | {
|
---|
| 743 | case RTNET_DHCP_MT_DISCOVER:
|
---|
| 744 | case RTNET_DHCP_MT_OFFER:
|
---|
| 745 | case RTNET_DHCP_MT_REQUEST:
|
---|
| 746 | case RTNET_DHCP_MT_DECLINE:
|
---|
| 747 | case RTNET_DHCP_MT_ACK:
|
---|
| 748 | case RTNET_DHCP_MT_NAC:
|
---|
| 749 | case RTNET_DHCP_MT_RELEASE:
|
---|
| 750 | case RTNET_DHCP_MT_INFORM:
|
---|
| 751 | break;
|
---|
| 752 |
|
---|
| 753 | default:
|
---|
| 754 | /* we don't know this message type, fail. */
|
---|
| 755 | return false;
|
---|
| 756 | }
|
---|
| 757 |
|
---|
| 758 | /* Found a known message type, consider the job done. */
|
---|
| 759 | if (pMsgType)
|
---|
| 760 | *pMsgType = MsgType;
|
---|
| 761 | return true;
|
---|
| 762 | }
|
---|
| 763 | }
|
---|
| 764 |
|
---|
| 765 | /* Skip the option. */
|
---|
| 766 | cbLeft -= pOpt->dhcp_len + sizeof(*pOpt);
|
---|
| 767 | pOpt = (PCRTNETDHCPOPT)((uint8_t const *)pOpt + pOpt->dhcp_len + sizeof(*pOpt));
|
---|
| 768 | }
|
---|
| 769 | }
|
---|
| 770 |
|
---|
| 771 | return true;
|
---|
| 772 | }
|
---|
[21337] | 773 | RT_EXPORT_SYMBOL(RTNetIPv4IsDHCPValid);
|
---|
[11049] | 774 |
|
---|