/* * Copyright (c) 2000-2009 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * Copyright (c) 1988, 1992, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)in_cksum.c 8.1 (Berkeley) 6/10/93 */ #include #include #include #include #include #include #include #define DBG_FNC_IN_CKSUM NETDBG_CODE(DBG_NETIP, (3 << 8)) /* * Checksum routine for Internet Protocol family headers (Portable Version). * * This routine is very heavily used in the network * code and should be modified for each CPU to be as fast as possible. */ union s_util { char c[2]; u_short s; }; union l_util { u_int16_t s[2]; u_int32_t l; }; union q_util { u_int16_t s[4]; u_int32_t l[2]; u_int64_t q; }; #define ADDCARRY(x) do { if (x > 65535) { x -= 65535; } } while (0) #define REDUCE32 \ { \ q_util.q = sum; \ sum = q_util.s[0] + q_util.s[1] + q_util.s[2] + q_util.s[3]; \ } #define REDUCE16 \ { \ q_util.q = sum; \ l_util.l = q_util.s[0] + q_util.s[1] + q_util.s[2] + q_util.s[3]; \ sum = l_util.s[0] + l_util.s[1]; \ ADDCARRY(sum); \ } #define REDUCE {l_util.l = sum; sum = l_util.s[0] + l_util.s[1]; ADDCARRY(sum);} u_int16_t inet_cksum_simple(struct mbuf *, int); u_int16_t inet_cksum_simple(struct mbuf *m, int len) { return (inet_cksum(m, 0, 0, len)); } u_short in_addword(u_short a, u_short b) { union l_util l_util; u_int32_t sum = a + b; REDUCE; return (sum); } u_short in_pseudo(u_int a, u_int b, u_int c) { u_int64_t sum; union q_util q_util; union l_util l_util; sum = (u_int64_t) a + b + c; REDUCE16; return (sum); } #if defined(__arm__) extern int cpu_in_cksum(struct mbuf *m, int len, int off, uint32_t initial_sum); u_int16_t inet_cksum(struct mbuf *m, unsigned int nxt, unsigned int skip, unsigned int len) { u_int32_t sum = 0; /* sanity check */ if ((m->m_flags & M_PKTHDR) && m->m_pkthdr.len < skip + len) { panic("inet_cksum: mbuf len (%d) < off+len (%d+%d)\n", m->m_pkthdr.len, skip, len); } /* include pseudo header checksum? */ if (nxt != 0) { struct ip *iph; if (m->m_len < sizeof (struct ip)) panic("inet_cksum: bad mbuf chain"); iph = mtod(m, struct ip *); sum = in_pseudo(iph->ip_src.s_addr, iph->ip_dst.s_addr, htonl(len + nxt)); } return (cpu_in_cksum(m, len, skip, sum)); } #else u_int16_t inet_cksum(struct mbuf *m, unsigned int nxt, unsigned int skip, unsigned int len) { u_short *w; u_int32_t sum = 0; int mlen = 0; int byte_swapped = 0; union s_util s_util; union l_util l_util; KERNEL_DEBUG(DBG_FNC_IN_CKSUM | DBG_FUNC_START, len,0,0,0,0); /* sanity check */ if ((m->m_flags & M_PKTHDR) && m->m_pkthdr.len < skip + len) { panic("inet_cksum: mbuf len (%d) < off+len (%d+%d)\n", m->m_pkthdr.len, skip, len); } /* include pseudo header checksum? */ if (nxt != 0) { struct ip *iph; if (m->m_len < sizeof (struct ip)) panic("inet_cksum: bad mbuf chain"); iph = mtod(m, struct ip *); sum = in_pseudo(iph->ip_src.s_addr, iph->ip_dst.s_addr, htonl(len + nxt)); } if (skip != 0) { for (; skip && m; m = m->m_next) { if (m->m_len > skip) { mlen = m->m_len - skip; w = (u_short *)(void *)(m->m_data+skip); goto skip_start; } else { skip -= m->m_len; } } } for (;m && len; m = m->m_next) { if (m->m_len == 0) continue; w = mtod(m, u_short *); if (mlen == -1) { /* * The first byte of this mbuf is the continuation * of a word spanning between this mbuf and the * last mbuf. * * s_util.c[0] is already saved when scanning previous * mbuf. */ s_util.c[1] = *(char *)w; sum += s_util.s; w = (u_short *)(void *)((char *)w + 1); mlen = m->m_len - 1; len--; } else { mlen = m->m_len; } skip_start: if (len < mlen) mlen = len; len -= mlen; /* * Force to even boundary. */ if ((1 & (uintptr_t) w) && (mlen > 0)) { REDUCE; sum <<= 8; s_util.c[0] = *(u_char *)w; w = (u_short *)(void *)((char *)w + 1); mlen--; byte_swapped = 1; } /* * Unroll the loop to make overhead from * branches &c small. */ while ((mlen -= 32) >= 0) { sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3]; sum += w[4]; sum += w[5]; sum += w[6]; sum += w[7]; sum += w[8]; sum += w[9]; sum += w[10]; sum += w[11]; sum += w[12]; sum += w[13]; sum += w[14]; sum += w[15]; w += 16; } mlen += 32; while ((mlen -= 8) >= 0) { sum += w[0]; sum += w[1]; sum += w[2]; sum += w[3]; w += 4; } mlen += 8; if (mlen == 0 && byte_swapped == 0) continue; REDUCE; while ((mlen -= 2) >= 0) { sum += *w++; } if (byte_swapped) { REDUCE; sum <<= 8; byte_swapped = 0; if (mlen == -1) { s_util.c[1] = *(char *)w; sum += s_util.s; mlen = 0; } else mlen = -1; } else if (mlen == -1) s_util.c[0] = *(char *)w; } if (len) printf("cksum: out of data by %d\n", len); if (mlen == -1) { /* The last mbuf has odd # of bytes. Follow the standard (the odd byte may be shifted left by 8 bits or not as determined by endian-ness of the machine) */ s_util.c[1] = 0; sum += s_util.s; } REDUCE; KERNEL_DEBUG(DBG_FNC_IN_CKSUM | DBG_FUNC_END, 0,0,0,0,0); return (~sum & 0xffff); } #endif