[4de817d] | 1 | /* |
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| 2 | * Copyright (c) 1988, 1992, 1993 |
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| 3 | * The Regents of the University of California. All rights reserved. |
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| 4 | * |
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| 5 | * Redistribution and use in source and binary forms, with or without |
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| 6 | * modification, are permitted provided that the following conditions |
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| 7 | * are met: |
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| 8 | * 1. Redistributions of source code must retain the above copyright |
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| 9 | * notice, this list of conditions and the following disclaimer. |
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| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
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| 11 | * notice, this list of conditions and the following disclaimer in the |
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| 12 | * documentation and/or other materials provided with the distribution. |
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| 13 | * 3. All advertising materials mentioning features or use of this software |
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| 14 | * must display the following acknowledgement: |
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| 15 | * This product includes software developed by the University of |
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| 16 | * California, Berkeley and its contributors. |
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| 17 | * 4. Neither the name of the University nor the names of its contributors |
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| 18 | * may be used to endorse or promote products derived from this software |
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| 19 | * without specific prior written permission. |
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| 20 | * |
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| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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| 31 | * SUCH DAMAGE. |
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| 32 | * |
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| 33 | * @(#)in_cksum.c 8.1 (Berkeley) 6/10/93 |
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| 34 | * $Id$ |
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| 35 | */ |
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| 36 | |
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| 37 | #include <sys/param.h> |
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| 38 | #include <sys/mbuf.h> |
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| 39 | |
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[23cdd84c] | 40 | #if (defined(__GNUC__) && (defined(__mc68000__) || defined(__m68k__)) && (!__mcf5200__)) |
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[4de817d] | 41 | |
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| 42 | #define REDUCE { sum = (sum & 0xFFFF) + (sum >> 16); if (sum > 0xFFFF) sum -= 0xFFFF; } |
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| 43 | |
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| 44 | /* |
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| 45 | * Motorola 68k version of Internet Protocol Checksum routine |
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| 46 | * W. Eric Norum |
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| 47 | * Saskatchewan Accelerator Laboratory |
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| 48 | * August, 1998 |
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| 49 | */ |
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| 50 | int |
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| 51 | in_cksum(m, len) |
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| 52 | struct mbuf *m; |
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| 53 | int len; |
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| 54 | { |
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| 55 | unsigned short *w; |
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| 56 | unsigned long sum = 0; |
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| 57 | int mlen = 0; |
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| 58 | int byte_swapped = 0; |
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| 59 | union { |
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| 60 | char c[2]; |
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| 61 | u_short s; |
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| 62 | } s_util; |
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| 63 | |
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| 64 | for ( ; m && len ; m = m->m_next) { |
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| 65 | if (m->m_len == 0) |
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| 66 | continue; |
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| 67 | w = mtod(m, u_short *); |
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| 68 | if (mlen == -1) { |
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| 69 | /* |
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| 70 | * The first byte of this mbuf is the continuation |
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| 71 | * of a word spanning between this mbuf and the |
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| 72 | * last mbuf. |
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| 73 | * |
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| 74 | * s_util.c[0] is already saved when scanning previous |
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| 75 | * mbuf. |
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| 76 | */ |
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| 77 | s_util.c[1] = *(char *)w; |
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| 78 | sum += s_util.s; |
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| 79 | w = (u_short *)((char *)w + 1); |
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| 80 | mlen = m->m_len - 1; |
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| 81 | len--; |
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| 82 | } else |
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| 83 | mlen = m->m_len; |
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| 84 | if (len < mlen) |
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| 85 | mlen = len; |
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| 86 | len -= mlen; |
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| 87 | |
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| 88 | /* |
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| 89 | * Force to longword boundary. |
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| 90 | */ |
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| 91 | if (3 & (int)w) { |
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| 92 | REDUCE; |
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| 93 | if ((1 & (int) w) && (mlen > 0)) { |
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| 94 | sum <<= 8; |
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| 95 | s_util.c[0] = *(u_char *)w; |
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| 96 | w = (u_short *)((char *)w + 1); |
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| 97 | mlen--; |
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| 98 | byte_swapped = 1; |
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| 99 | } |
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| 100 | if ((2 & (int) w) && (mlen >= 2)) { |
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| 101 | sum += *w++; |
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| 102 | mlen -= 2; |
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| 103 | } |
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| 104 | } |
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| 105 | |
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| 106 | /* |
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| 107 | * Sum all the longwords in the buffer. |
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| 108 | * See RFC 1071 -- Computing the Internet Checksum. |
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| 109 | * It should work for all 68k family members. |
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| 110 | */ |
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| 111 | { |
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| 112 | unsigned long tcnt = mlen, t1; |
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| 113 | __asm__ volatile ( |
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| 114 | "movel %2,%3\n\t" |
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| 115 | "lsrl #6,%2 | count/64 = # loop traversals\n\t" |
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| 116 | "andl #0x3c,%3 | Then find fractions of a chunk\n\t" |
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| 117 | "negl %3\n\t | Each long uses 4 instruction bytes\n\t" |
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| 118 | "andi #0xf,%%cc | Clear X (extended carry flag)\n\t" |
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| 119 | "jmp %%pc@(lcsum2_lbl-.-2:b,%3) | Jump into loop\n" |
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| 120 | "lcsum1_lbl: | Begin inner loop...\n\t" |
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| 121 | "movel %1@+,%3 | 0: Fetch 32-bit word\n\t" |
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| 122 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 123 | "movel %1@+,%3 | 1: Fetch 32-bit word\n\t" |
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| 124 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 125 | "movel %1@+,%3 | 2: Fetch 32-bit word\n\t" |
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| 126 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 127 | "movel %1@+,%3 | 3: Fetch 32-bit word\n\t" |
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| 128 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 129 | "movel %1@+,%3 | 4: Fetch 32-bit word\n\t" |
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| 130 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 131 | "movel %1@+,%3 | 5: Fetch 32-bit word\n\t" |
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| 132 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 133 | "movel %1@+,%3 | 6: Fetch 32-bit word\n\t" |
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| 134 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 135 | "movel %1@+,%3 | 7: Fetch 32-bit word\n\t" |
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| 136 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 137 | "movel %1@+,%3 | 8: Fetch 32-bit word\n\t" |
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| 138 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 139 | "movel %1@+,%3 | 9: Fetch 32-bit word\n\t" |
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| 140 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 141 | "movel %1@+,%3 | A: Fetch 32-bit word\n\t" |
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| 142 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 143 | "movel %1@+,%3 | B: Fetch 32-bit word\n\t" |
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| 144 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 145 | "movel %1@+,%3 | C: Fetch 32-bit word\n\t" |
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| 146 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 147 | "movel %1@+,%3 | D: Fetch 32-bit word\n\t" |
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| 148 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 149 | "movel %1@+,%3 | E: Fetch 32-bit word\n\t" |
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| 150 | "addxl %3,%0 | Add word + previous carry\n\t" |
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| 151 | "movel %1@+,%3 | F: Fetch 32-bit word\n\t" |
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| 152 | "addxl %3,%0 | Add word + previous carry\n" |
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| 153 | "lcsum2_lbl:\n\tdbf %2,lcsum1_lbl | (NB- dbra doesn't affect X)\n\t" |
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| 154 | "movel %0,%3 | Fold 32 bit sum to 16 bits\n\t" |
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| 155 | "swap %3 | (NB- swap doesn't affect X)\n\t" |
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| 156 | "addxw %3,%0 |\n\t" |
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| 157 | "moveq #0,%3 | Add in last carry\n\t" |
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| 158 | "addxw %3,%0 |\n\t" |
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| 159 | "andl #0xffff,%0 | Mask to 16-bit sum\n" : |
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| 160 | "=d" (sum), "=a" (w), "=d" (tcnt) , "=d" (t1) : |
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| 161 | "0" (sum), "1" (w), "2" (tcnt) : |
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| 162 | "cc", "memory"); |
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| 163 | } |
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| 164 | mlen &= 3; |
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| 165 | |
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| 166 | /* |
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| 167 | * Soak up the last 1, 2 or 3 bytes |
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| 168 | */ |
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| 169 | while ((mlen -= 2) >= 0) |
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| 170 | sum += *w++; |
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| 171 | if (byte_swapped) { |
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| 172 | REDUCE; |
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| 173 | sum <<= 8; |
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| 174 | byte_swapped = 0; |
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| 175 | if (mlen == -1) { |
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| 176 | s_util.c[1] = *(char *)w; |
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| 177 | sum += s_util.s; |
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| 178 | mlen = 0; |
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| 179 | } else |
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| 180 | mlen = -1; |
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| 181 | } else if (mlen == -1) |
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| 182 | s_util.c[0] = *(char *)w; |
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| 183 | } |
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| 184 | if (len) |
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| 185 | sum = 0xDEAD; |
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| 186 | if (mlen == -1) { |
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| 187 | /* The last mbuf has odd # of bytes. Follow the |
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| 188 | standard (the odd byte may be shifted left by 8 bits |
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| 189 | or not as determined by endian-ness of the machine) */ |
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| 190 | s_util.c[1] = 0; |
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| 191 | sum += s_util.s; |
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| 192 | } |
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| 193 | REDUCE; |
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| 194 | return (~sum & 0xffff); |
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| 195 | } |
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| 196 | |
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| 197 | |
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| 198 | #else |
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| 199 | /* |
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| 200 | * Checksum routine for Internet Protocol family headers (Portable Version). |
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| 201 | * |
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| 202 | * This routine is very heavily used in the network |
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| 203 | * code and should be modified for each CPU to be as fast as possible. |
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| 204 | */ |
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| 205 | |
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| 206 | #define ADDCARRY(x) (x > 65535 ? x -= 65535 : x) |
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| 207 | #define REDUCE \ |
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| 208 | {l_util.l = sum; sum = l_util.s[0] + l_util.s[1]; ADDCARRY(sum);} |
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| 209 | |
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| 210 | int |
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| 211 | in_cksum(m, len) |
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| 212 | register struct mbuf *m; |
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| 213 | register int len; |
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| 214 | { |
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| 215 | register u_short *w; |
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| 216 | register int sum = 0; |
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| 217 | register int mlen = 0; |
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| 218 | int byte_swapped = 0; |
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| 219 | |
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| 220 | union { |
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| 221 | char c[2]; |
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| 222 | u_short s; |
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| 223 | } s_util; |
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| 224 | union { |
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| 225 | u_short s[2]; |
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| 226 | long l; |
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| 227 | } l_util; |
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| 228 | |
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| 229 | for (;m && len; m = m->m_next) { |
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| 230 | if (m->m_len == 0) |
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| 231 | continue; |
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| 232 | w = mtod(m, u_short *); |
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| 233 | if (mlen == -1) { |
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| 234 | /* |
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| 235 | * The first byte of this mbuf is the continuation |
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| 236 | * of a word spanning between this mbuf and the |
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| 237 | * last mbuf. |
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| 238 | * |
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| 239 | * s_util.c[0] is already saved when scanning previous |
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| 240 | * mbuf. |
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| 241 | */ |
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| 242 | s_util.c[1] = *(char *)w; |
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| 243 | sum += s_util.s; |
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| 244 | w = (u_short *)((char *)w + 1); |
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| 245 | mlen = m->m_len - 1; |
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| 246 | len--; |
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| 247 | } else |
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| 248 | mlen = m->m_len; |
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| 249 | if (len < mlen) |
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| 250 | mlen = len; |
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| 251 | len -= mlen; |
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| 252 | /* |
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| 253 | * Force to even boundary. |
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| 254 | */ |
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| 255 | if ((1 & (int) w) && (mlen > 0)) { |
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| 256 | REDUCE; |
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| 257 | sum <<= 8; |
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| 258 | s_util.c[0] = *(u_char *)w; |
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| 259 | w = (u_short *)((char *)w + 1); |
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| 260 | mlen--; |
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| 261 | byte_swapped = 1; |
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| 262 | } |
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| 263 | /* |
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| 264 | * Unroll the loop to make overhead from |
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| 265 | * branches &c small. |
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| 266 | */ |
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| 267 | while ((mlen -= 32) >= 0) { |
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| 268 | sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3]; |
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| 269 | sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7]; |
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| 270 | sum += w[8]; sum += w[9]; sum += w[10]; sum += w[11]; |
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| 271 | sum += w[12]; sum += w[13]; sum += w[14]; sum += w[15]; |
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| 272 | w += 16; |
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| 273 | } |
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| 274 | mlen += 32; |
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| 275 | while ((mlen -= 8) >= 0) { |
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| 276 | sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3]; |
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| 277 | w += 4; |
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| 278 | } |
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| 279 | mlen += 8; |
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| 280 | if (mlen == 0 && byte_swapped == 0) |
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| 281 | continue; |
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| 282 | REDUCE; |
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| 283 | while ((mlen -= 2) >= 0) { |
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| 284 | sum += *w++; |
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| 285 | } |
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| 286 | if (byte_swapped) { |
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| 287 | REDUCE; |
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| 288 | sum <<= 8; |
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| 289 | byte_swapped = 0; |
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| 290 | if (mlen == -1) { |
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| 291 | s_util.c[1] = *(char *)w; |
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| 292 | sum += s_util.s; |
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| 293 | mlen = 0; |
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| 294 | } else |
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| 295 | mlen = -1; |
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| 296 | } else if (mlen == -1) |
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| 297 | s_util.c[0] = *(char *)w; |
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| 298 | } |
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| 299 | if (len) |
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| 300 | printf("cksum: out of data\n"); |
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| 301 | if (mlen == -1) { |
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| 302 | /* The last mbuf has odd # of bytes. Follow the |
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| 303 | standard (the odd byte may be shifted left by 8 bits |
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| 304 | or not as determined by endian-ness of the machine) */ |
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| 305 | s_util.c[1] = 0; |
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| 306 | sum += s_util.s; |
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| 307 | } |
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| 308 | REDUCE; |
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| 309 | return (~sum & 0xffff); |
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| 310 | } |
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| 311 | #endif |
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